JP5875482B2 - Antenna characteristic measurement system using optical electric field sensor and antenna characteristic measurement method using optical electric field sensor - Google Patents

Description

  The present invention relates to a characteristic measurement system and a characteristic measurement method for measuring antenna performance.

  A parasitic optical modulator that is incorporated in a broadcasting or communication transmitting antenna and modulates laser light in response to electromagnetic waves transmitted from the transmitting antenna, and a laser beam is introduced into the parasitic optical modulator while introducing laser light. A monitoring device that receives the laser light modulated by the feed type optical modulator and monitors the radio wave transmission state of the transmitting antenna, and the monitoring device is connected to the transmitting antenna via an optical fiber. A laser light source for introducing laser light to the feed optical modulator and a light receiver for receiving the modulated laser light guided from the non-feed optical modulator via the optical fiber; An antenna monitoring system that monitors transmission of radio waves from a transmission antenna from a modulation component of received laser light is disclosed (see Patent Document 1).

  In this antenna monitoring system, a parasitic optical modulator is incorporated into a transmitting antenna (transmitting antenna unit), laser light is introduced from a monitoring device to the parasitic optical modulator via an optical fiber, and the optical fiber is connected via an optical fiber. The monitoring device receives the laser light modulated by the parasitic optical modulator, and monitors the operating state of the transmission antenna from the modulation component of the laser light received by the monitoring device. The monitoring apparatus selectively introduces laser light into each optical fiber via an optical switch, and receives return laser light from a parasitic optical modulator connected to an optical fiber. The optical switch is driven so that the optical fiber is always selected cyclically.

JP 2005-86347 A

  In the antenna monitoring system disclosed in Patent Document 1, a plurality of parasitic optical modulators are always installed in the vicinity of a transmission antenna, and the operation state of the transmission antenna is monitored using these parasitic optical modulators. Since this antenna monitoring system uses an optical switch to switch and introduce laser light into these parasitic optical modulators at predetermined time intervals, when the environment around the transmission antenna changes depending on the introduction time of the laser light, As a result, the operational state of the antenna changes and the measurement accuracy of the operational state varies, and a stable operational state cannot be measured, making it difficult to accurately determine normal or abnormal operation of the antenna. Further, this antenna monitoring system does not measure the phase of the transmitting antenna and cannot grasp the change in the phase of the antenna, and therefore cannot grasp the operation state of the antenna due to the change in the phase.

  An object of the present invention is to provide an antenna characteristic measurement system and characteristic measurement method using an optical electric field sensor that can accurately determine the performance of a plurality of existing antennas and can evaluate the performance of these antennas with high accuracy. It is to provide. Another object of the present invention is to use an optical electric field sensor capable of measuring the power levels and phase differences of a plurality of existing antennas and accurately judging the performance of the antennas based on the measured power levels and phase differences. It is an object to provide a characteristic measurement system and characteristic measurement method for an antenna.

  The first premise of the present invention for solving the above-mentioned problem is that the input light is modulated by modulating the intensity of the input light in accordance with the electric field intensity of the electromagnetic wave transmitted from the antenna to be measured. An optical electric field sensor that emits modulated light, a light source that emits input light to the optical electric field sensor, and an O / E converter that converts the modulated light emitted from the optical electric field sensor into an electric signal, and O / E conversion It is an antenna characteristic measurement system using an optical electric field sensor that measures the performance of the antenna based on the electrical signal output from the device.

The characteristic of the antenna characteristic measurement system of the present invention in the first premise is a plurality of first to n-th existing antennas in which antennas to be measured have the same power level or different power levels, the same phase or different phases, An optical electric field sensor is formed from a first optical electric field sensor and a second optical electric field sensor that are detachably installed at predetermined positions of the first to n-th existing antennas, and the characteristic measurement system includes first and second optical electric field sensors. Is installed in the first existing antenna, and the first measuring means for simultaneously measuring the power level and phase difference of the first existing antenna by the modulated light emitted from the optical electric field sensor, and the first optical electric field sensor for the first existing antenna with the state of the installation is maintained, the second optical electric field sensor removed from the first existing antenna is installed in order second to n existing antenna, Second measuring means for simultaneously measuring the power level and phase difference in the existing antennas by the modulated light emitted from these optical electric field sensors, the power level measured by the first measuring means, and the power level measured by the second measuring means Level comparison value calculation means for calculating a level comparison value from the above, phase difference comparison value calculation means for calculating a phase difference comparison value from the phase difference measured by the first measurement means and the phase difference measured by the second measurement means; It is in having.

  As an example of the antenna characteristic measurement system according to the present invention, the level calculated by the level comparison value calculation unit after the elapse of a predetermined period from when the antenna is installed is the level calculated by the level comparison value calculation unit when the antenna is installed. Level comparison means for comparing with a comparison value or a design level comparison value of the existing antennas calculated in advance before installation of the antenna is included.

  As another example of the antenna characteristic measurement system according to the present invention, the level comparison value calculated by the level comparison value calculation means uses the power level of the first existing antenna measured by the first measurement means as the denominator, A first ratio with the power level of the first existing antenna measured by the measuring means as a numerator is calculated, and the power levels of the second to nth existing antennas measured by the first measuring means are used as a denominator, and the second measuring means After calculating the second ratio using the measured power levels of the second to n-th existing antennas as the numerator, the power ratio is calculated using the first ratio as the denominator and the second ratio as the numerator.

  As another example of the antenna characteristic measurement system according to the present invention, the system calculates the phase difference comparison value calculated by the phase difference comparison value calculation means after the elapse of a predetermined period from the time of installation of the antenna. A phase difference comparison means for comparing with a phase difference comparison value calculated by the means or a design phase difference comparison value of the existing antennas calculated in advance before installation of the antenna.

  As another example of the antenna characteristic measurement system according to the present invention, the phase difference comparison value calculated by the phase difference comparison value calculation unit is calculated based on the phase of the first existing antenna measured by the first measurement unit. Calculating the first phase difference obtained by subtracting the phase of the second to n-th existing antennas measured by the second measurement means, and measuring the second to n-th times measured by the second measurement means from the phase of the first existing antenna measured by the second measurement means. This is the phase difference obtained by subtracting the first phase difference from the second phase difference after calculating the second phase difference obtained by subtracting the phase of the existing antenna.

  As another example of the antenna characteristic measurement system according to the present invention, in the system, the installation position of the first and second optical electric field sensors in the first measurement means with respect to the first existing antenna is at the physical center of the first existing antenna. They are at approximately the same distance.

  As another example of the antenna characteristic measurement system according to the present invention, in the system, the first to n-th existing antennas have substantially the same shape, and the first optical electric field sensor in the first measurement means is installed on the first existing antenna. The position and the installation position of the second optical electric field sensor with respect to the second to n-th existing antennas in the second measuring means are substantially the same.

  As another example of the antenna characteristic measurement system according to the present invention, the system emits light from the second optical electric field sensor with respect to the length (L1) of the first optical fiber that transmits the modulated light emitted from the first optical electric field sensor. The phase difference (ΔL) (L1−L2) of the length (L2) of the second optical fiber that transmits the modulated light can accurately measure the phase against the change of the temperature environment during the phase measurement. The length (L2) of the second optical fiber is adjusted with respect to the length (L1) of the first optical fiber so as to be within the appropriate range, and the path difference (ΔL) is expressed by the equation: ΔL ≦ ΔPh / ( Calculated by 0.0576 × Frq × ΔT) (ΔL = path difference [m], ΔPh = phase difference [deg], Frq = frequency of electromagnetic wave [GHz], ΔT = temperature fluctuation range during measurement [° C.], 0.0576 = Phase coefficient [deg / GHz ℃ · m]).

  The second premise of the present invention for solving the above-mentioned problem is that the input light is modulated by modulating the intensity of the input light according to the electric field intensity of the electromagnetic wave transmitted from the antenna to be measured. An optical electric field sensor that emits modulated light, a light source that emits input light to the optical electric field sensor, and an O / E converter that converts the modulated light emitted from the optical electric field sensor into an electric signal, and O / E conversion This is a method for measuring the characteristics of an antenna using an optical electric field sensor that measures the performance of the antenna based on an electrical signal output from the device.

  As a feature of the antenna characteristic measurement method of the present invention in the second premise, in the characteristic measurement method, the antenna to be measured has a plurality of first to nth elements having the same power level or different power levels, the same phase, or different phases. An existing antenna, and an optical electric field sensor is formed from a first optical electric field sensor and a second optical electric field sensor which are detachably installed at predetermined positions of the first to n-th existing antennas, and the characteristic measurement method includes: A first measuring step of installing a second optical electric field sensor on the first existing antenna and simultaneously measuring a power level and a phase difference of the first existing antenna by modulated light emitted from the optical electric field sensor; While maintaining the installation state of the first optical electric field sensor, the second optical electric field sensor removed from the first existing antenna is sequentially installed on the second to nth existing antennas. A second measurement step of simultaneously measuring the power level and the phase difference in the existing antennas by the modulated light emitted from the optical electric field sensors, the power level measured by the first measurement step, and the power level measured by the second measurement step; A level comparison value calculation step for calculating a level comparison value from the phase difference comparison value calculation step for calculating a phase difference comparison value from the phase difference measured by the first measurement step and the phase difference measured by the second measurement step. Is to have.

  As an example of the antenna characteristic measurement method according to the present invention, the characteristic measurement method calculates the level comparison value calculated by the level comparison value calculation step after a predetermined period from the installation of the antenna by the level comparison value calculation step when the antenna is installed. And a level comparison step for comparing with the calculated level comparison value or the design level comparison value calculation of those existing antennas calculated in advance before antenna installation.

  As another example of the antenna characteristic measurement method according to the present invention, the level comparison value calculated by the level comparison value calculation step uses the power level of the first existing antenna measured by the first measurement step as a denominator, While calculating the 1st ratio which makes the numerator the electric power level of the 1st existing antenna measured by the measurement process, the electric power level of the 2nd-nth existing antennas measured by the 1st measurement process is made into a denominator, and by the 2nd measurement process After calculating the second ratio using the measured power levels of the second to n-th existing antennas as the numerator, the power ratio is calculated using the first ratio as the denominator and the second ratio as the numerator.

  As another example of the antenna characteristic measurement method according to the present invention, the characteristic measurement method uses the phase difference comparison value calculated by the phase difference comparison value calculation step after the elapse of a predetermined period from the time of antenna installation as a phase difference comparison at the time of antenna installation. There is a phase difference comparison step for comparing with a phase difference comparison value calculated by the value calculation step or a design phase difference comparison value calculation of those existing antennas calculated in advance before installing the antenna.

  As another example of the antenna characteristic measurement method according to the present invention, the phase difference comparison value calculated by the phase difference comparison value calculation step is calculated from the phase of the first existing antenna measured by the first measurement step. Calculating the first phase difference obtained by subtracting the phase of the second to n-th existing antennas measured in step S2 and the second to n-th measured in the second measurement step from the phase of the first existing antenna measured in the second measurement step. This is the phase difference obtained by subtracting the first phase difference from the second phase difference after calculating the second phase difference obtained by subtracting the phase of the existing antenna.

  As another example of the antenna characteristic measurement method according to the present invention, in the characteristic measurement method, the installation positions of the first and second optical electric field sensors in the first measurement step with respect to the first existing antenna are the physical positions of the first existing antenna. The distance is approximately equal to the center.

  As another example of the antenna characteristic measurement method according to the present invention, in the characteristic measurement method, the first to n-th existing antennas have substantially the same shape, and the first existing antenna of the first optical electric field sensor in the first measurement step. The installation position with respect to the second to n-th existing antennas of the second optical electric field sensor in the second measurement step is substantially the same.

  As another example of the antenna characteristic measurement method according to the present invention, in the characteristic measurement method, the second optical electric field sensor with respect to the length (L1) of the first optical fiber that transmits the modulated light emitted from the first optical electric field sensor. The phase difference (ΔL) (L1−L2) of the length (L2) of the second optical fiber that transmits the modulated light emitted from the phase accurately measures the phase against the change of the temperature environment at the time of phase measurement. Is adjusted within the appropriate range, the length (L2) of the second optical fiber is adjusted with respect to the length (L1) of the first optical fiber, and the path difference (ΔL) is expressed by the equation: ΔL ≦ ΔPh /(0.0576×Frq×ΔT) (ΔL = path difference [m], ΔPh = phase difference [deg], Frq = frequency of electromagnetic wave [GHz], ΔT = temperature fluctuation range during measurement [° C. ], 0.0576 = Phase coefficient [deg / GHz ℃ · m]).

  According to the antenna characteristic measurement system and characteristic measurement method of the present invention, the power level and phase difference of the first existing antenna are simultaneously measured by the modulated light emitted from the first and second optical electric field sensors, and the first existing antenna is measured. The second optical electric field sensor removed from the first existing antenna is sequentially installed on the second to nth existing antennas while maintaining the installation state of the first optical electric field sensor with respect to the antenna, and then the modulation emitted from the optical electric field sensors While simultaneously measuring the power level and phase difference in these existing antennas with light, the power level and phase difference measured by the first measuring means (first measuring step) and the power measured by the second measuring means (second measuring step) Since the level comparison value and phase difference comparison value are calculated from the level and phase difference, the power level of these existing antennas By measuring the phase difference at the same time, it is possible to prevent variations in level and phase difference caused by measuring the power level and phase difference after the environment changes around the antenna at different times. An accurate phase difference comparison value can be calculated. Since the antenna characteristic measurement system and characteristic measurement method can calculate accurate level comparison values and phase difference comparison values of the existing antennas, it is possible to accurately grasp the performance of the existing antennas. Performance can be evaluated with high accuracy. Since the antenna characteristic measurement system and characteristic measurement method can accurately evaluate the performance of the antenna based on the level comparison value and phase difference comparison value of the existing antennas, any abnormality or failure of any of the existing antennas is detected. Can be detected quickly, and by repairing and replacing the existing antenna in which such abnormality has occurred, the influence on other normal existing antennas can be minimized.

  The level comparison value calculated by the level comparison value calculation means (level comparison value calculation step) after the elapse of a predetermined period from the time of antenna installation, or the level comparison value calculated by the level comparison value calculation means (level comparison value calculation step) at the time of antenna installation or The antenna characteristic measurement system and characteristic measurement method to be compared with the design level comparison values of the existing antennas calculated in advance before installing the antennas are to obtain the level comparison values of the existing antennas during or before the antenna installation. In addition, by comparing the level comparison value calculated after a predetermined period from the time of antenna installation with the level comparison value obtained at the time of antenna installation or before antenna installation, If the level comparison value calculated after a certain period of time has elapsed since installation, Na abnormality such as a failure or defect in their existing antenna after a predetermined period of time it can be determined to be caused from the time of installation, these existing antennas abnormality can be accurately grasped. The antenna characteristic measurement system and characteristic measurement method compares the level comparison value obtained at the time of antenna installation or before installation with the level comparison value calculated after the lapse of a predetermined period from the time of installation. Abnormalities such as defects can be judged, so that any failure or malfunction of any of these existing antennas can be quickly discovered, and the existing antenna in which such an abnormality has occurred can be repaired or replaced promptly. And the influence on other normal existing antennas can be minimized.

  The first ratio calculated from the power level of the first existing antenna measured by the first measurement means (first measurement step) and the power level of the first existing antenna measured by the second measurement means (second measurement step) is a denominator. And the power level of the second to n-th existing antennas measured by the first measurement means (first measurement step) and the power level of the second to n-th existing antennas measured by the second measurement means (second measurement step) In the antenna characteristic measurement system and characteristic measurement method for calculating the power ratio using the second ratio calculated from the numerator as the numerator, the power level is corrected by calculating the first ratio, whereby the accurate power of the existing antennas is corrected. Since the ratio (level comparison value) can be calculated, the performance of the existing antennas can be judged accurately, and the performance of these existing antennas can be evaluated with high accuracy. Can. The antenna characteristic measurement system and characteristic measurement method can accurately evaluate the performance of the antenna using the calculated power ratio, so that any failure or malfunction of the existing antenna can be quickly discovered. Thus, the existing antenna in which such an abnormality has occurred can be repaired and replaced quickly, and the influence on other normal existing antennas can be minimized.

  The phase difference comparison value calculated by the phase difference comparison value calculation means (phase difference comparison value calculation process) after the elapse of a predetermined period from the time of installation of the antenna is calculated by the phase difference comparison value calculation means (phase difference comparison value calculation process) when the antenna is installed. The antenna characteristic measurement system and characteristic measurement method to be compared with the measured phase difference comparison value or the phase difference comparison value in the design of the existing antenna calculated in advance before the antenna installation are The phase difference comparison value is calculated and the phase difference comparison value calculated after a predetermined period from the time of antenna installation is compared with the phase difference comparison value calculated at the time of antenna installation or before antenna installation. If the phase difference comparison value calculated after the specified period has deviated from the phase difference comparison value obtained before installation or Tena abnormality such as a failure or defect in their existing antenna after a predetermined period of time it can be determined to be caused from the time of installation, these existing antennas abnormality can be accurately grasped. The antenna characteristic measurement system and characteristic measurement method compares the phase difference comparison value obtained at the time of installation or before installation of the antenna with the phase difference comparison value calculated after a predetermined period from the time of installation. Abnormalities such as malfunctions and malfunctions can be grasped, so any malfunctions or malfunctions of any of these existing antennas can be quickly discovered, and existing antennas with such malfunctions can be quickly repaired or replaced. And the influence on other normal existing antennas can be minimized.

  A first phase difference obtained by subtracting the phases of the second to n-th existing antennas measured by the first measurement unit (first measurement step) from the phase of the first existing antenna measured by the first measurement unit (first measurement step). And calculating and subtracting the phases of the second to n-th existing antennas measured by the second measurement means (second measurement step) from the phases of the first existing antenna measured by the second measurement means (second measurement step). The antenna characteristic measurement system and characteristic measurement method for calculating the phase difference by subtracting the first phase difference from the second phase difference after calculating the two phase differences are obtained by subtracting the first phase difference from the second phase difference. Since the phase difference (phase difference comparison value) is calculated and the occurrence of an abnormality such as a failure or malfunction in the existing antenna can be determined using the phase difference, the performance of the antenna can be accurately evaluated. The antenna characteristic measurement system and characteristic measurement method can quickly find any failure or malfunction of the existing antenna using the phase difference obtained by subtracting the first phase difference from the second phase difference. Thus, the existing antenna in which such an abnormality has occurred can be repaired and replaced promptly, and the influence on other normal existing antennas can be minimized.

  Antenna characteristic measurement system in which the installation positions of the first and second optical electric field sensors in the first measurement means (first measurement step) with respect to the first existing antenna are substantially equal to the physical center of the first existing antenna. The characteristic measurement method is to measure the power level and phase difference in the optical electric field sensors by setting the installation positions of the first and second optical electric field sensors to be substantially equal distances from the physical center of the first existing antenna. The conditions are the same, and the power level and the phase difference measured using the modulated light emitted from the optical electric field sensors do not vary due to the difference in the measurement conditions. The accurate power level and accurate phase difference of the antenna can be measured.

  The shapes of the first to n-th existing antennas are substantially the same, and the installation position of the first optical electric field sensor with respect to the first existing antenna and the second measurement means (second measurement step) in the first measurement means (first measurement step). The antenna characteristic measurement system and characteristic measurement method in which the installation positions of the second optical electric field sensor with respect to the second to n-th existing antennas are substantially the same, the installation position of the first optical electric field sensor with respect to the first existing antenna and the second By making the installation positions of the optical electric field sensors with respect to the second to n-th existing antennas substantially the same, the measurement conditions of the power level and phase difference in the optical electric field sensors become the same, and the modulated light emitted from these optical electric field sensors The power level and phase difference measured by using the optical field sensor will not vary due to the difference in measurement conditions. It can be measured, such power levels and accurate phase. Since the antenna characteristic measurement system and characteristic measurement method can measure the accurate power level and phase difference of the existing antennas, the performance of the existing antennas can be accurately grasped, and the performance of the existing antennas is high. Can be evaluated with accuracy.

  The path difference of the length of the second optical fiber transmitting the modulated light emitted from the second optical electric field sensor with respect to the length of the first optical fiber transmitting the modulated light emitted from the first optical electric field sensor is a phase measurement. Of an antenna in which the length of the second optical fiber is adjusted with respect to the length of the first optical fiber so that the phase can be accurately measured with respect to changes in the temperature environment over time. In the characteristic measurement system and the characteristic measurement method, the length of the optical fiber extending from the first and second optical electric field sensors and transmitting the phase data varies depending on the temperature environment at the time of measurement, thereby using the optical electric field sensors. Even if fluctuation (deviation) occurs in the measured phase, the phase deviation measured using the second optical electric field sensor approximates the phase deviation measured using the first optical electric field sensor. doing Preparative can be easily demonstrated, by using these optical electric field sensor can measure their existing antenna phase with high reliability. In the antenna characteristic measurement system and characteristic measurement method, the phase of the existing antenna is obtained from the second optical electric field sensor with respect to the length of the first optical fiber that transmits the modulated light emitted from the first optical electric field sensor. The length of the second optical fiber is adjusted with respect to the length of the first optical fiber so that the path difference in the length of the second optical fiber that transmits the modulated light is within an appropriate range. The phase measured using the first and second optical electric field sensors does not greatly deviate, and the substantially accurate phase is measured by these optical electric field sensors, and the measurement accuracy of the phase difference with respect to these existing antennas can be improved. it can. In the antenna characteristic measurement system and characteristic measurement method, the path difference (ΔL) is calculated by the equation: ΔL ≦ ΔPh / (0.0576 × Frq × ΔT), and the first and second photoelectric elements are used by using the equation. When the phase shift amount (ΔPh) measured using the field sensor is set to an allowable range, and the length of each optical fiber can be obtained based on the allowable range, the phase of these existing antennas is obtained. The length of each optical fiber can be adjusted so that the path difference of each optical fiber is within an appropriate range.

The block diagram of the characteristic measurement system shown as an example. The block diagram of the measuring device shown as an example. The block diagram which shows an example of the optical electric field sensor used for a characteristic measurement system. The block diagram of the optical modulator of the optical electric field sensor of FIG. FIG. 5 is an end view taken along line 5-5 of FIG. The figure which shows the path | route difference of the optical fiber in a characteristic measurement system. FIG. 5 is a diagram illustrating an example of calculating a phase shift amount and a phase difference and an example of a phase shift amount and a phase difference calculated by the formula. The figure which shows an example which calculates the length and path | route difference of an optical fiber, and the length and path | route difference of an optical fiber calculated by the formula. The perspective view of the antenna shown in the state which installed the 1st and 2nd optical electric field sensor in the 1st existing antenna. The figure which shows the installation position of the 1st and 2nd optical electric field sensor with respect to a 1st existing antenna. Explanatory drawing in the case of measuring a power level and a phase difference with a 1st measurement means. The perspective view of the antenna shown in the state which installed the 1st and 2nd optical electric field sensor in the 1st and 2nd existing antenna. The figure which shows the installation position of the 1st and 2nd optical electric field sensor with respect to a 1st and 2nd existing antenna. Explanatory drawing in the case of measuring a power level and a phase difference by a 2nd measurement means. The figure which shows an example of the calculated electric power ratio ((DELTA) P). The figure which shows an example of the calculated phase difference comparison value ((DELTA) Ph).

  Details of an antenna characteristic measurement system and characteristic measurement method using an optical electric field sensor according to the present invention will be described with reference to the accompanying drawings such as FIG. 1 which is a configuration diagram of an antenna characteristic measurement system 10 shown as an example. It is as follows. 2 is a configuration diagram of the measurement device 13 shown as an example, and FIG. 3 is a configuration diagram showing an example of the optical electric field sensors 12A and 12B used in the antenna characteristic measurement system 10. 4 is a configuration diagram of the optical modulator 31 of the optical electric field sensors 12A and 12B of FIG. 3, and FIG. 5 is an end view taken along line 5-5 of FIG. 4 and 5, the stretching direction (the propagation direction of light (laser light)) is indicated by an arrow A (only in FIG. 4), the width direction is indicated by an arrow B, and the thickness direction is indicated by an arrow C (only in FIG. 5).

  The characteristic measurement system 10 (characteristic measurement method) includes a plurality of first to sixteenth existing antennas (first to nth existing antennas) having the same power level or different power levels, the same phase, or different phases (see FIGS. 9 and 12). ) Are measured, and the performance of the existing antennas is measured from the measured power level (power ratio) and phase difference. The characteristic measurement system 10 is composed of a transmission / reception device 11, a first optical electric field sensor 12A, a second optical electric field sensor 12B, and a measurement device 13.

  As shown in FIG. 1, the transmission / reception device 11 is formed of an optical transmission unit 14, an optical reception unit 15, and optical circulators 16A and 16B. The optical transmitter 14 includes an optical modulator light source 17 (light source), a polarization beam combiner 18 and an optical coupler 19 (optical distributor). In the optical transmitter 14, the light source 17 for the optical modulator and the polarization combiner 18 are connected via the polarization maintaining optical fiber 20, and the polarization combiner 18 and the optical coupler 19 are connected via the single mode optical fiber 21. It is connected.

  The light source for optical modulator 17 has a first light source for light modulator 22A that emits a first laser beam (first input light) having a predetermined polarization plane, and a polarization plane that is 90 ° different from that of the first laser beam. The second light source 22B for the optical modulator that emits the second laser light (second input light) is formed. The polarization beam combiner 18 combines the laser beams emitted (supplied) from the first light source 22A for the light modulator and the second light source 22B for the light modulator into a combined laser beam whose polarization planes are orthogonal to each other.

  The optical coupler 19 is connected to the optical circulators 16A and 16B via the single mode optical fiber 21. The optical coupler 19 distributes the combined laser light combined by the polarization beam combiner 18 into two, emits one combined laser light to the optical circulator 16A (first optical electric field sensor 12A), and the other combined laser. Light is emitted to the optical circulator 16B (second optical electric field sensor 12B).

  The first light source for optical modulator 22A is a laser light source that emits (supplies) semiconductor laser light to the polarization beam combiner 18 (first and second optical electric field sensors 12A and 12B). The second light source for optical modulator 22B The laser light source emits (supplies) semiconductor laser light to the polarization beam combiner 18 (first and second optical electric field sensors 12A and 12B). The semiconductor laser beams emitted from the light sources 22A and 22B have a wavelength of 1.55 μm and an electric energy of 50 mW.

  The laser light emitted from the light sources 22A and 22B may have a wavelength in the range of 1.26 to 1.68 μm, and the amount of power in the range of 1 to 100 mW. When the wavelength of the laser light exceeds 1.68 μm, unnecessary noise is generated in the optical fibers 20 and 21, and loss occurs in the laser light emitted from the light sources 22A and 22B. When the power amount of the laser light exceeds 100 mW, the laser light having an unnecessary power amount is supplied to the first and second optical electric field sensors 12A and 12B. As a result, the power consumption of the characteristic measurement system 10 is reduced. It cannot be reduced.

  The optical circulators 16A and 16B emit the combined laser beam only in one direction. The optical circulator 16 </ b> A is connected to the first optical electric field sensor 12 </ b> A (the input / output optical waveguide 33 a of the optical modulator 31) via the single mode optical fiber 21. The optical circulator 16B is connected to the second optical electric field sensor 12B (input / output optical waveguide 33a of the optical modulator 31) via the single mode optical fiber 21.

  The optical receiver 15 includes a first O / E converter 23A, a second O / E converter 23B, a first amplifier 24A, and a second amplifier 24B. The first O / E converter 23A is connected to the optical circulator 16A (the input / output optical waveguide 33a of the optical modulator 31 of the first optical electric field sensor 12A) via the single mode optical fiber 21. The second O / E converter 23B is connected to the optical circulator 16B (the input / output optical waveguide 33a of the optical modulator 31 of the second optical electric field sensor 12B) via the single mode optical fiber 21.

  The first O / E converter 23A and the amplifier 24A are electrically connected via a feeder line 25 (coaxial cable). The second O / E converter 23B and the amplifier 24B are electrically connected via a feeder line 25 (coaxial cable). The first and second O / E converters 23A and 23B receive the modulated light from the first and second optical electric field sensors 12A and 12B (optical modulators) via the optical circulators 16A and 16B, and the modulated light is electrically After conversion to a signal, the electrical signal is output to the amplifiers 24A and 24B. The amplifiers 24A and 24B are electrically connected to the measuring device 13 via a feeder line 25 (coaxial cable).

  The measuring device 13 measures the power level of the electromagnetic wave transmitted from each existing antenna based on the electrical signal output from the first and second O / E converters 23A and 23B and amplified through the amplifiers 24A and 24B. Then, the power ratio of the power level in each existing antenna is calculated. The measuring device 13 measures the phase of the electromagnetic wave transmitted from each existing antenna based on the electric signal output from the first and second O / E converters 23A and 23B and amplified through the amplifiers 24A and 24B. The phase difference in each existing antenna is calculated.

  As shown in FIG. 2, the measuring device 13 includes first and second distributors 26A and 26B, first and second power detectors 27A and 27B, first and second phase detectors 28A and 28B, and a computer 29. Formed from. The first distributor 26A is electrically connected to the first amplifier 24A via a feeder line 25 (coaxial cable). The second distributor 26B is electrically connected to the second amplifier 24B via the feeder line 25 (coaxial cable). The first power detector 27A and the first phase detector 28A are electrically connected to the first distributor 26A via the feeder line 25 (coaxial cable). The second power detector 27B and the second phase detector 28B are electrically connected to the second distributor 26B via the feeder line 25 (coaxial cable). The first and second power detectors 27A and 27B and the first and second phase detectors 28A and 28B are electrically connected to the computer 29 via a feeder line 25 (coaxial cable).

  The first distributor 26A distributes the electrical signal output from the first amplifier 24A to the first power detector 27A and the first phase detector 28A. The second distributor 26B distributes the electrical signal output from the second amplifier 24B to the second power detector 27B and the second phase detector 28B. The first power detector 27A measures the power level from the electrical signal (modulated light emitted from the first optical electric field sensor 12A), and transfers the measured power level to the computer 29. The second power detector 27 </ b> B measures the power level from the electrical signal (the modulated light emitted from the second optical electric field sensor 12 </ b> B), and transfers the measured power level to the computer 29. The first phase detector 28A measures the phase from the electrical signal (the modulated light emitted from the first optical electric field sensor 12A) and transfers the measured phase to the computer 29. The second phase detector 28B measures the phase from the electrical signal (modulated light emitted from the second optical electric field sensor 12B) and transfers the measured phase to the computer 29.

  The computer 29 includes a central processing unit and a memory, and incorporates a large-capacity hard disk. An input device (not shown) such as a keyboard and a mouse is connected to the computer 29 via an interface, and an output device (not shown) such as a display and a printer is connected via the interface. The computer 29 activates an application stored in the memory based on control by the operating system, and executes various commands according to the activated application.

  As shown in FIG. 3, each of the first and second optical electric field sensors 12A and 12B is made up of a housing 30 and a reflective light modulator 31 installed inside the housing 30 via a predetermined fixing means. It has been. The reflection type optical modulator 31 receives the electromagnetic wave transmitted from each of the existing antennas by the antenna 35 described later, and the intensity of the laser light (input light) incident from the optical circulators 16A and 16B is determined based on the electromagnetic wave received by the antenna 35. The modulated light, which is modulated in accordance with the electric field intensity and modulates the laser light, is emitted to the optical circulators 16A and 16B (first and second O / E converters 23A and 23B). The light modulator 31 may be a transmissive type in addition to the reflective type.

The reflective optical modulator 31 of the first and second optical electric field sensors 12A and 12B is a single crystal substrate made of an X-cut lithium niobate (LiNbO ₃ ) crystal (material), which is a crystal substrate having an electrooptic effect. 32, a Mach-Zehnder optical waveguide 33 formed by Ti diffusion on the upper surface side of the substrate 32, a buffer layer 34 formed on the upper surface side of the substrate 32, and an antenna 35 formed on the buffer layer 34. And a light reflecting portion 37 installed at one end portion 36 of the substrate 32.

  The Mach-Zehnder type optical waveguide 33 extends to the other end of the substrate 32, and includes one input / output optical waveguide 33a on which laser light (input light and modulated light) is incident or emitted, and the input / output optical waveguide 33a. And two phase shift waveguides 33b and 33c extending in a bifurcated manner. The input / output optical waveguide 33a is connected to the optical circulators 16A and 16B via the single mode optical fiber 21. The phase shift optical waveguides 33b and 33c are spaced apart by a predetermined dimension in the width direction and extend in parallel to each other. The separation dimension of the phase shift optical waveguides 33b and 33c is in the range of 20 to 50 μm.

  The input / output optical waveguide 33a and the phase shift optical waveguides 33b and 33c have the same width dimension W in the direction intersecting the extending direction. The phase shift optical waveguides 33b and 33c have the same length in the extending direction. The width dimension W of these optical waveguides 33a to 33c is in the range of 5 to 10 μm. The length dimension in the extending direction of each of the phase shift optical waveguides 33b and 33c is in the range of 10 to 30 mm. The width dimension W of the optical waveguides 33a to 33c, the length dimension of the phase shift optical waveguides 33b and 33c, and the separation dimension of the phase shift optical waveguides 33b and 33c are not particularly limited, and these dimensions are arbitrarily set. Can do.

The buffer layer 34 is provided for the purpose of preventing part of the laser light propagating through the optical waveguide 33 from being absorbed by the antenna 35. The buffer layer 34 is made of SiO ₂ and has a thickness dimension of about 200 nm. The antenna 35 is stretched so that one of them is located on the input / output optical waveguide 33a side (end portion 38 side) and the other is located on the light reflecting portion 37 side (end portion 36 side). Lined up in the direction. The antennas 35 are Cr and Au films formed by sputtering or the like. The antennas 35 receive the electromagnetic waves transmitted from the existing antennas and induce an electric signal proportional to the electric field strength of the received electromagnetic waves. The frequency band of electromagnetic waves that can be received by the antenna 35 is not particularly limited.

  The antenna 35 located on the light reflecting portion 37 side has an extending portion 35a disposed between the phase shift optical waveguides 33b and 33c. The extending portion 35a extends in the extending direction in parallel with the optical waveguides 33b and 33c. The length dimension of the extending portion 35a of the antenna 35 in the extending direction is 5 mm. The antenna 35 positioned on the input / output optical waveguide 33a side has extending portions 35b and 35c arranged on both sides of the extending portion 35a of the antenna 35 with the phase shift optical waveguides 33b and 33c interposed therebetween. The extending portions 35b and 35c extend in the extending direction in parallel with the phase shift optical waveguides 33b and 33c. The length dimension of the extending portions 35b and 35c of the antenna 35 in the extending direction is 5 mm.

  In addition, there is no limitation in particular in the length dimension of the extending direction of the extending | stretching site | parts 35a-35c of the antenna 35, The length can be arbitrarily set according to the electric power level of the electromagnetic waves to sense. For example, when the length of the extending portions 35a to 35c when the power level of the electromagnetic wave to be sensed is set to a predetermined value is the reference length, the extending portion is increased as the power level of the electromagnetic wave to be sensed increases from the predetermined value. The length dimension of 35a-35c is made shorter than the reference length.

  6 is a diagram showing the path difference ΔL of the optical fiber 21 (L1, L2) in the characteristic measurement system 10, and FIG. 7 is an equation for calculating the phase shift amount (Ph) and the phase difference (ΔPh) and It is a figure which shows an example of the amount of phase shift (Ph) and phase difference ((DELTA) Ph) calculated by the type | formula. FIG. 8 is a diagram showing an example of calculating the length (L) and path difference (ΔL) of the optical fiber 21 and an example of the length (L) and path difference (ΔL) of the optical fiber 21 calculated by the expression. It is.

  In this characteristic measurement system 10 (characteristic measurement method), as shown in FIG. 6, the sensors 12A and 12B in the existing antennas of the electromagnetic waves transmitted from the existing antennas using the first and second optical electric field sensors 12A and 12B. When the phase difference between the respective installation positions is obtained while measuring the phase at the installation positions of the first optical electric field sensor 12A, the second photoelectric sensor with respect to the length L1 of the first optical fiber 21A that transmits the modulated light. The phase difference (ΔL) (L1−L2) of the length L2 of the second optical fiber 21B that transmits the modulated light emitted from the field sensor 12B accurately measures the phase with respect to changes in the temperature environment at the time of phase measurement. Within the proper range (the path difference (ΔL) of the length (L2) of the second optical fiber 21B to the length (L1) of the first optical fiber 21A is positive and minor. The length (L2) of the second optical fiber 21B is adjusted with respect to the length (L1) of the first optical fiber 21A.

  Specifically, the path difference (ΔL) (L1−L2) is calculated by the formula: ΔL ≦ ΔPh / (0.0576 × Frq × ΔT), and the path difference (ΔL) calculated by the formula is used. The length (L1) of the first optical fiber 21A and the length (L2) of the second optical fiber 21B are required.

  In the above equation, ΔL is the path difference [m], and ΔPh is the phase difference [deg]. Frq is the frequency [GHz] of the electromagnetic wave, ΔT is the temperature fluctuation range [° C.] at the time of phase measurement, and 0.0576 is the phase coefficient [deg / GHz · ° C. · m]. The length of the first optical fiber 21A is the length of the optical fiber 21 that connects the output side of the first optical electric field sensor 12A and the input side of the first O / E converter 23A, and the second optical fiber 21B. Is the length of the optical fiber 21 connecting the output side of the second optical electric field sensor 12B and the input side of the second O / E converter 23B.

  As shown in FIG. 7, the phase shift amount (Ph) can be calculated by Expression (1): and the phase difference (ΔPh) can be calculated by Expression (2): Further, the length (L) of the optical fiber with respect to the phase shift amount (Ph) can be calculated by the equation (3): as shown in FIG. 8, and the path difference (ΔL) with respect to the phase difference (ΔPh). Can be calculated by Equation (4):

  For example, in FIG. 7, the frequency (Frq) is 0.531 [GHz], the temperature fluctuation width (ΔT) is 60 [° C.], the length (L) of the optical fiber is 200 [m], and the phase coefficient is 0.0576. In this case, the phase shift amount (Ph) = 367.0 (°) is calculated by the equation (1), the frequency (Frq) is 0.531 [GHz], and the temperature fluctuation range (ΔT) is 60 [° C.]. When the optical fiber length (L) is 201 [m] and the phase coefficient is 0.0576, the phase shift amount (Ph) = 368.0 [°] is calculated. Further, the phase difference (ΔPh) = approximately ± 1.9 [°] is calculated by the equation (2).

  Further, when the frequency (Frq) is 0.531 [GHz], the temperature fluctuation range (ΔT) is 50 [° C.], the length (L) of the optical fiber is 150 [m], and the phase coefficient is 0.0576, The phase shift amount (Ph) = 229.4 (°) is calculated by the equation (1), the frequency (Frq) is 0.531 [GHz], the temperature fluctuation range (ΔT) is 50 [° C.], and the optical fiber When the length (L) is 152 [m] and the phase coefficient is 0.0576, the phase shift amount (Ph) = 232.5 [°] is calculated. Further, the phase difference (ΔPh) = approximately ± 3.1 [°] is calculated by the equation (2).

  In FIG. 8, the phase shift amount (Ph) is 367.0 (°), the frequency (Frq) is 0.531 [GHz], the temperature fluctuation range (ΔT) is 60 [° C.], and the phase coefficient is 0.0576. In some cases, the length (L) of the optical fiber is calculated by Equation (3) = 200 [m], the phase shift amount (Ph) is 368.9 (°), and the frequency (Frq) is 0.531 [GHz]. When the temperature fluctuation range (ΔT) is 60 [° C.] and the phase coefficient is 0.0576, the length (L) of the optical fiber = 201 [m] is calculated. Furthermore, the path difference (ΔL) = about ± 1 [m] is calculated by the equation (4).

  When the phase shift amount (Ph) is 229.4 (°), the frequency (Frq) is 0.531 [GHz], the temperature fluctuation range (ΔT) is 50 [° C.], and the phase coefficient is 0.0576. , The length (L) of the optical fiber is calculated by Equation (3) = 150 [m], the phase shift amount (Ph) is 232.5 (°), the frequency (Frq) is 0.531 [GHz], When the temperature fluctuation range (ΔT) is 50 [° C.] and the phase coefficient is 0.0576, the length (L) of the optical fiber = 152 [m] is calculated. Further, the path difference (ΔL) = about ± 2 [m] is calculated by the equation (4).

  By using these formulas (1) to (4), the length (L1) of the first optical fiber 21A and the second optical fiber 21B are adjusted so that the phase shift amount (Ph) is within an appropriate range. The length (L2) and the second length (L1) of the first optical fiber 21A and the second length can be determined so that the path difference (ΔL) is within an appropriate range of at least one of plus and minus. The length (L2) of the optical fiber 21B can be obtained.

  FIG. 9 is a perspective view of the antenna 39 shown in a state where the first and second optical electric field sensors 12A and 12B are installed on the first existing antenna 39a, and FIG. 10 shows the first and second antennas for the first existing antenna 39a. It is a figure which shows the installation position of optical electric field sensor 12A, 12B. FIG. 11 is an explanatory diagram when the power level and the phase difference are measured by the first measuring means.

  The antenna 39 (broadcasting antenna or transmitting antenna) in FIG. 9 is that of four faces and four stages having the first to sixteenth existing antennas, but only the first two lower stages of the first to eighth existing antennas 39a to 39h are illustrated. The illustration of the 9th to 16th existing antennas in the upper two stages is omitted. The first to sixteenth existing antennas have substantially the same shape, and have the same power level or different power levels, the same phase, or different phases.

  The hard disk of the computer 29 forming the measuring device 13 stores antenna identifiers for identifying the first existing antenna to the sixteenth existing antenna, and sensor identifiers for identifying the first and second optical electric field sensors 12A and 12B. ing. Further, the hard disk of the computer 29 stores the design (theoretical) power ratio (ΔP) (level comparison value) of the existing antennas calculated in advance before the antenna is installed, and is calculated in advance before the antenna is installed. The design (theoretical) phase difference (ΔPh) (phase difference comparison value) of these existing antennas is stored.

  The hard disk of the computer 29 stores an allowable range (± α [%]) of the power ratio (ΔP) and an allowable range (± β [deg]) of the comparative phase difference (ΔPh). The allowable range (± α [%]) and the allowable range (± β [deg]) can be freely changed by the input device. It is assumed that the allowable range (± α [%]) is set to ± 5 [%] and the allowable range (± β [deg]) is set to ± 10 [deg].

An example of a procedure for measuring the power level, phase, and phase difference of an existing antenna in the characteristic measurement system 10 (characteristic measurement method) will be described as follows. The measurement of the power level and the measurement of the phase difference will be described using only the first and second existing antennas 39a and 39b as an example. First, when the antenna 39 is installed, as shown in FIG. 9, the first and second optical electric field sensors 12A and 12B are installed at predetermined positions of the first existing antenna 39a.

When the first and second optical electric field sensors 12A and 12B are installed in the first existing antenna 39a, the installation positions of the first and second optical electric field sensors 12A and 12B with respect to the first existing antenna 39a are as shown in FIG. The optical electric field sensors 12A and 12B are installed on the antenna 39a so as to have a substantially equal distance from the physical center 40 of the first existing antenna 39a. Therefore, when the first and second optical electric field sensors 12A and 12B are installed on the first existing antenna 39a, the separation distance of the first optical electric field sensor 12A from the physical center 40 of the antenna 39a and the second optical electric field sensor. The separation distance of 12B is substantially equal.

After the first and second optical electric field sensors 12A and 12B are installed on the first existing antenna 39a, the characteristic measurement system 10 is activated. When measuring the power level, phase, and phase difference in the characteristic measurement system 10, the temperature fluctuation width (ΔT) in the first optical fiber 21A and the second optical fiber 21B is the same, and in these optical electric field sensors 12A and 12B, The frequency (Frq) of the electromagnetic wave to be measured is the same. When electromagnetic waves are transmitted from the first existing antenna 39a, the electromagnetic waves are received by the characteristic measurement system 10 (the antennas 35 of the first and second optical electric field sensors 12A and 12B).

  The optical modulator first and second light sources 22A and 22B emit laser light having a wavelength of 1.55 μm and an electric energy of 50 mW. The laser light enters the polarization beam combiner 18 from the light sources 22A and 22B through the optical fiber 20, and is combined by the polarization beam combiner 18 into a combined laser beam whose polarization planes are orthogonal to each other. The combined laser light enters the optical coupler 19 through the optical fiber 21, is divided into two by the optical coupler 19, and then enters the optical circulators 16 </ b> A and 16 </ b> B. The optical circulators 16A and 16B cause the combined laser light to enter the optical modulators 31 of the first and second optical electric field sensors 12A and 12B.

  In the reflection type optical modulator 31, as indicated by an arrow X1 in FIG. 4, the combined laser light emitted from the optical circulators 16A and 16B (polarization synthesizer 18) is a waveguide from the input / output port of the input / output optical waveguide 33a. 33a enters the waveguides 33b and 33c after being divided into two (demultiplexed) by the phase shift waveguides 33b and 33c. Thereafter, the modulated light modulated from the combined laser light is reflected by the light reflecting portion 37, and, as indicated by the arrow X2, from the input / output port of the input / output optical waveguide 33a to the optical fibers 21A and 21B (optical circulators 16A and 16B). Emitted.

  In the optical modulator 31, when a voltage is applied to the antenna 35 (between the extended portion 35a of the antenna 35 and the extended portions 35b and 35c) by the electric field strength (high frequency signal) of the electromagnetic wave received by the antenna 35, FIG. Electric fields opposite to each other in the Z-axis direction indicated by an arrow Z are applied to the phase shift optical waveguides 33b and 33c (see FIG. 5).

  By applying an electric field in the opposite direction to the phase shift optical waveguides 33b and 33c, the directions of refractive index change due to the electro-optic effect in the optical waveguides 33b and 33c are opposite to each other and propagate through the phase shift waveguides 33b and 33c. A phase shift in the opposite direction occurs in the laser beam (one of the combined laser beams). As a result, the laser beams reflected by the reflector 37 interfere with each other when coupled in the input / output optical waveguide 33d, and the intensity of the laser beams is modulated to become modulated light.

  The modulated light modulated by the optical modulator 31 is emitted from the input / output optical waveguide 33a, enters the first O / E converter 23A from the optical circulator 16A through the optical fiber 21A, and passes through the optical fiber 21B. The light enters the second O / E converter 23B from the circulator 16B. These O / E converters 23A and 23B generate electric signals obtained by converting the modulated light, and output the electric signals to the amplifiers 24A and 24B. The amplifiers 24A and 24B amplify the electrical signals output from the O / E converters 23A and 23B, and output the amplified electrical signals to the measuring device 13.

  In the measuring device 13, the electrical signal output from the amplifier 21A (O / E converter 20A) is input to the distributor 26A, and the electrical signal output from the amplifier 21B (O / E converter 20B) is distributed. 26B. The distributor 26A distributes the electrical signal, and outputs the distributed electrical signal to the power detection unit 27A and the phase detection unit 28A. The distributor 26B distributes the electrical signal and outputs the distributed electrical signal to the power detection unit 27B and the phase detection unit 28B.

  The power detection unit 27A converts the electrical signal output from the distributor 26A into the power level of the first existing antenna 39a, and outputs the converted power level to the computer 29. The power detection unit 27B converts the electrical signal output from the distributor 26B into the power level of the first existing antenna 39a, and outputs the converted power level to the computer 29. The central processing unit of the computer 29 stores the power level of the first existing antenna 39a output from the power detection units 27A and 27B in the hard disk (first measurement means, first measurement step).

  The power level (a1-1) of the first existing antenna 39a at the time of installation of the antenna 39 output from the power detection unit 27A is the antenna identifier of the first existing antenna 39a, the sensor identifier of the first optical electric field sensor 12A, and the level identifier. And stored in the hard disk in a state associated with the measurement date and time (year / month / day / minute) (first measurement means, first measurement step). The power level (a1-2) of the first existing antenna 39a at the time of installation of the antenna 39 output from the power detection unit 27B is the antenna identifier of the first existing antenna 39a, the sensor identifier of the second optical electric field sensor 12B, and the level identifier. , And stored in the hard disk in a state associated with the measurement date (year / month / day / minute).

  The phase detector 28A converts the electrical signal output from the distributor 26A into the phase of the first existing antenna 39a, and outputs the converted phase to the computer 29. The phase detector 28B converts the electrical signal output from the distributor 26B into the phase of the first existing antenna 39a, and outputs the converted phase to the computer 29. The central processing unit of the computer 29 stores the phase of the first existing antenna 39a output from the phase detection units 28A and 28B in the hard disk (first measurement means, first measurement step).

  The phase (b1-1) of the first existing antenna 39a at the time of installation of the antenna 39 output from the phase detector 28A is the antenna identifier of the first existing antenna 39a, the sensor identifier of the first optical electric field sensor 12A, the phase identifier, It is stored in the hard disk in a state associated with the measurement date (year / month / day / minute). The phase (b1-2) of the first existing antenna 39a at the time of installation of the antenna 39 output from the phase detector 28B is the antenna identifier of the first existing antenna 39a, the sensor identifier of the second optical electric field sensor 12B, the phase identifier, It is stored in the hard disk in a state associated with the measurement date (year / month / day / minute).

  The central processing unit of the computer 29 calculates the first phase difference (ph1) = (b1-1) − (b1-2) between the phase (b1-1) and the phase (b1-2), and the phase difference ( ph1) is stored on the hard disk. The first phase difference (ph1) is stored in the hard disk in a state associated with the antenna identifier, the phase identifier, and the measurement date (year / month / day / hour).

  12 is a perspective view of the antenna 39 shown in a state where the first and second optical electric field sensors 12A and 12B are installed on the first and second existing antennas 39a and 39b, and FIG. 13 shows the first and second existing antennas 39a and 39b. It is a figure which shows the installation position of 1st and 2nd optical electric field sensor 12A, 12B with respect to antenna 39a, 39b. FIG. 14 is an explanatory diagram when the power level and the phase difference are measured by the second measuring means.

The first and second optical electric field sensors 12A and 12B are used to measure the power level and phase of the first existing antenna 39a, and the power levels (a1-1), (a1-2) and phase (b1-1), (B1-2) After storing the phase difference (ph1) in the hard disk, the second optical electric field sensor 12B is connected to the first existing antenna 39a in a state where the first optical electric field sensor 12A is installed on the first existing antenna 39a. The optical electric field sensor 12B is installed at a predetermined position of the second existing antenna 39b.

When the second optical electric field sensor 12B removed from the first existing antenna 39a is installed in the second existing antenna 39b, the installation position of the first optical electric field sensor 12A with respect to the first existing antenna 39a and the as the installation position becomes substantially equal to the second existing antenna 39b of the two light field sensor 12B, the optical electric field sensor 12B is installed in the antenna 39b. Therefore, when the first optical electric field sensor 12A is installed on the first existing antenna 39a and the second optical electric field sensor 12B is installed on the second existing antenna 39b, the first relative to the physical center 40 of the antennas 39a and 39b is obtained. The separation distance of the optical electric field sensor 12A is substantially equal to the separation distance of the second optical electric field sensor 12B.

After the second optical electric field sensor 12B is installed on the second existing antenna 39b in a state where the first optical electric field sensor 12A is installed on the first existing antenna 39a, the characteristic measurement system 10 is started again. When electromagnetic waves are transmitted from the first and second existing antennas 39a and 39b, the electromagnetic waves are received by the characteristic measurement system 10 (the antennas 35 of the first and second optical electric field sensors 12A and 12B).

As in the case where the first and second optical electric field sensors 12A and 12B are installed in the first existing antenna 39a and the power level and phase of the antenna 39a are measured using the optical electric field sensors 12A and 12B, the reflection type light modulation is performed. The modulated light modulated by the device 31 is emitted from the input / output optical waveguide 33a, enters the first O / E converter 23A from the optical circulator 16A through the optical fiber 21A, and from the optical circulator 16B through the optical fiber 21B. The light enters the second O / E converter 23B. These O / E converters 23A and 23B generate electric signals obtained by converting the modulated light, and output the electric signals to the amplifiers 24A and 24B. The amplifiers 24A and 24B amplify the electrical signals output from the O / E converters 23A and 23B, and output the amplified electrical signals to the measuring device 13.

  The power detector 27A of the measuring device 13 converts the electrical signal output from the distributor 26A into the power level of the first existing antenna 39a, and outputs the converted power level to the computer 29. The power detection unit 27B converts the electrical signal output from the distributor 26B into the power level of the second existing antenna 39b, and outputs the converted power level to the computer 29. The central processing unit of the computer 29 stores the power levels of the first and second existing antennas 39a and 39b output from the power detection units 27A and 27B in the hard disk (second measurement means, second measurement step).

  After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the power level (a2-1) of the first existing antenna 39a output from the power detection unit 27A when the antenna 39 is installed is the first 1 is stored in the hard disk in a state associated with the antenna identifier of the existing antenna 39a, the sensor identifier of the first optical electric field sensor 12A, the level identifier, and the measurement date and time (year / month / day / hour). After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the power level (a2-2) of the second existing antenna 39b output from the power detection unit 27B when the antenna 39 is installed is 2 Stored in the hard disk in a state associated with the antenna identifier of the existing antenna 39b, the sensor identifier of the second optical electric field sensor 12B, the level identifier, and the measurement date / time (year / month / day / hour).

  The phase detector 28A of the measuring device 13 converts the electrical signal output from the distributor 26A into the phase of the first existing antenna 39a, and outputs the converted phase to the computer 29. The phase detection unit 28B converts the electrical signal output from the distributor 26B into the phase of the second existing antenna 39b, and outputs the converted phase to the computer 29. The computer 29 stores the phases of the first and second existing antennas 39a and 39b output from the phase detectors 28A and 28B in the hard disk (second measuring means, second measuring step).

  After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the phase (b2-1) of the first existing antenna 39a output from the phase detector 28A when the antenna 39 is installed is the first The information is stored in the hard disk in a state associated with the antenna identifier of the existing antenna 39a, the sensor identifier of the first optical electric field sensor 12A, the phase identifier, and the measurement date (year / month / day / hour). After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the phase (b2-2) of the second existing antenna 39b output from the phase detector 28B when the antenna 39 is installed is the second The information is stored in the hard disk in a state associated with the antenna identifier of the existing antenna 39b, the sensor identifier of the second optical electric field sensor 12B, the phase identifier, and the measurement date (year / month / day / hour).

  The central processing unit of the computer 29 calculates the second phase difference (ph2) = (b2-1) − (b2-2) between the phase (b2-1) and the phase (b2-2), and the phase difference ( ph2) is stored on the hard disk. The second phase difference (ph2) is stored in the hard disk in a state associated with the antenna identifier, the phase identifier, and the measurement date / time (year / month / day / minute).

  The central processing unit of the computer 29 has the power level (a1-1) of the first existing antenna 39a measured by the first measuring means (first measuring process), and the second measured by the first measuring means (first measuring process). The power level (a1-2) of the existing antenna 39b, the power level (a2-1) of the first existing antenna 39a measured by the second measurement means (second measurement step), and the second measurement means (second measurement step). Using the measured power level (a2-2) of the second existing antenna 39b, a first power ratio (level comparison value) when the antenna 39 is installed is calculated (level comparison value calculation means, level comparison value calculation step).

  Specifically, a first ratio having the power level (a1-1) as a denominator and the power level (a2-1) as a numerator is calculated, and the power level (a1-2) is set as a denominator. The second ratio with 2) as a numerator is calculated, and the first ratio {(a2-1) / (a1-1)} is used as the denominator, and the second ratio {(a2-2) / (a1-2) } As a numerator, the first power ratio (ΔP1) [%] = {(a2-2) / (a1-2)} / {(a2-1) / (a1-1)} is calculated. The central processing unit of the computer 29 stores the calculated power ratio (ΔP2) in the hard disk. The first power ratio (ΔP1) is stored in the hard disk in a state associated with the antenna identifier, the level identifier, and the measurement date / time (year / month / day / hour).

  The central processing unit of the computer 29 uses the first phase difference (ph1) and the second phase difference (ph2) to calculate the first comparison phase difference (ΔPh1) (phase difference comparison value) when the antenna 39 is installed ( (Phase difference comparison value calculation means, phase difference comparison value calculation step). Specifically, the phase difference (ph1) is subtracted from the phase difference (ph2), and the first phase difference comparison value (ΔPh1) [deg] = (ph2) − (ph1) is calculated. The central processing unit of the computer 29 stores the calculated phase difference comparison value (ΔPh1) in the hard disk. The first phase difference comparison value (ΔPh1) is stored in the hard disk in a state associated with the antenna identifier, the phase identifier, and the measurement date (year / month / day / hour).

Although not described, the second optical electric field sensor 12B is installed in order from the third existing antenna 39c to the 16th existing antenna in a state where the first optical electric field sensor 12A is installed on the first existing antenna 39a. The power level and phase of these existing antennas at the time of installing 39 are measured, and the power ratio (ΔP) and phase difference comparison value (ΔPh) at the time of installing antenna 39 are calculated, and the calculated power ratio (ΔP) and phase difference comparison are calculated. The value (ΔPh) is stored in the hard disk of the computer 29.

  In the characteristic measurement system 10 (characteristic measurement method), after a predetermined period has elapsed since the installation of the antenna 39, the power levels and phases of the existing antennas are measured again using the first and second optical electric field sensors 12A and 12B. The power ratio (ΔP) and the phase difference comparison value (ΔPh) are calculated. An example of the procedure for measuring the power level, phase, and phase difference after the elapse of a predetermined period from when the antenna 39 is installed is as follows.

After a predetermined period has elapsed since the installation of the antenna 39, the first and second optical electric field sensors 12A and 12B are installed at predetermined positions of the first existing antenna 39a (incorporated in FIGS. 9 and 11). When the first and second optical electric field sensors 12A and 12B are installed in the first existing antenna 39a, the installation positions of the first and second optical electric field sensors 12A and 12B with respect to the first existing antenna 39a are as shown in FIG. The optical electric field sensors 12A and 12B are installed on the antenna 39a so as to be substantially the same distance from the physical center 40 of the first existing antenna 39a (in FIG. 10).

After the first and second optical electric field sensors 12A and 12B are installed on the first existing antenna 39a, the characteristic measurement system 10 is activated. When measuring the power level, phase, and phase difference in the characteristic measurement system 10, the temperature fluctuation width (ΔT) in the first optical fiber 21A and the second optical fiber 21B is the same, and in these optical electric field sensors 12A and 12B, The frequency (Frq) of the electromagnetic wave to be measured is the same.

  When electromagnetic waves are transmitted from the first existing antenna 39a, the electromagnetic waves are received by the characteristic measurement system 10 (the antennas 35 of the first and second optical electric field sensors 12A and 12B). Similar to the case of measuring the power level and phase when the antenna 39 is installed, the modulated light modulated by the reflection type optical modulator 31 is emitted from the input / output optical waveguide 33a, passes through the optical fiber 21A, and is output from the optical circulator 16A. The light enters the 1O / E converter 23A and enters the second O / E converter 23B from the optical circulator 16B through the optical fiber 21B. These O / E converters 23A and 23B generate electric signals obtained by converting the modulated light, and output the electric signals to the amplifiers 24A and 24B. The amplifiers 24A and 24B amplify the electrical signals output from the O / E converters 23A and 23B, and output the amplified electrical signals to the measuring device 13.

  The power detector 27A of the measuring device 13 converts the electrical signal output from the distributor 26A into the power level of the first existing antenna 39a, and outputs the converted power level to the computer 29. The power detection unit 27B converts the electrical signal output from the distributor 26B into the power level of the first existing antenna 39a, and outputs the converted power level to the computer 29. The central processing unit of the computer 29 stores the power level of the first existing antenna 39a output from the power detection units 27A and 27B in the hard disk (first measurement means, first measurement step).

  The power level (c1-1) of the first existing antenna 39a output from the power detection unit 27A after a predetermined period from the installation of the antenna 39 is the antenna identifier of the first existing antenna 39a, the sensor of the first optical electric field sensor 12A. It is stored in the hard disk in a state associated with the identifier, the level identifier, and the measurement date (year / month / day / hour) (first measurement means, first measurement step). The power level (c1-2) of the first existing antenna 39a output from the power detection unit 27B after the elapse of a predetermined period from the installation time of the antenna 39 is the antenna identifier of the first existing antenna 39a, the sensor of the second optical electric field sensor 12B. It is stored in the hard disk in a state associated with the identifier, the level identifier, and the measurement date (year / month / day / hour).

  The phase detector 28A of the measuring device 13 converts the electrical signal output from the distributor 26A into the phase of the first existing antenna 39a, and outputs the converted phase to the computer 29. The phase detector 28B converts the electrical signal output from the distributor 26B into the phase of the first existing antenna 39a, and outputs the converted phase to the computer 29. The central processing unit of the computer 29 stores the phase of the first existing antenna 39a output from the phase detection units 28A and 28B in the hard disk (first measurement means, first measurement step).

  The phase (d1-1) of the first existing antenna 39a output from the phase detection unit 28A after a predetermined period from the installation of the antenna 39 is the antenna identifier of the first existing antenna 39a and the sensor identifier of the first optical electric field sensor 12A. , The phase identifier, and the measurement date (year / month / day / minute) in a state associated with the hard disk. The phase (d1-2) of the first existing antenna 39a after a predetermined period has elapsed since the installation of the antenna 39 output from the phase detector 28B is the antenna identifier of the first existing antenna 39a and the sensor identifier of the second optical electric field sensor 12B. , The phase identifier, and the measurement date (year / month / day / minute) in a state associated with the hard disk.

  The central processing unit of the computer 29 calculates the third phase difference (ph3) = (d1-1) − (d1-2) between the phase (d1-1) and the phase (d1-2), and the phase difference ( ph3) is stored on the hard disk. The third phase difference (ph3) is stored in the hard disk in a state associated with the antenna identifier, the phase identifier, and the measurement date (year / month / day / hour).

The first and second optical electric field sensors 12A and 12B are used to measure the power level and phase of the first existing antenna 39a after a predetermined period has elapsed since the installation of the antenna 39, and the power levels (c1-1), (c1- 2), the phases (d1-1), (d1-2), and the third phase difference (ph3) are stored in the hard disk, and then the first optical electric field sensor 12A is installed in the first existing antenna 39a. The two-optical electric field sensor 12B is removed from the first existing antenna 39a, and the optical electric field sensor 12B is installed at a predetermined position of the second existing antenna 39b (refer to FIGS. 12 and 14).

When the second optical electric field sensor 12B removed from the first existing antenna 39a is installed in the second existing antenna 39b, the installation position of the first optical electric field sensor 12A with respect to the first existing antenna 39a and the second optical electric field sensor 12B 2 The optical electric field sensor 12B is installed on the antenna 39b so that the installation position with respect to the existing antenna 39b is substantially the same ( refer to FIG. 13) .

After the second optical electric field sensor 12B is installed on the second existing antenna 39b while the first optical electric field sensor 12A is installed on the first existing antenna 39a, the characteristic measurement system 10 is started again. When electromagnetic waves are transmitted from the first and second existing antennas 39a and 39b, the electromagnetic waves are received by the characteristic measurement system 10 (the antennas 35 of the first and second optical electric field sensors 12A and 12B).

After the elapse of a predetermined period from when the antenna 39 is installed, the first and second optical electric field sensors 12A and 12B are installed in the first existing antenna 39a, and the power level and phase of the antenna 39a are adjusted using the optical electric field sensors 12A and 12B. Similarly to the case of measurement, the modulated light modulated by the reflective optical modulator 31 is emitted from the input / output optical waveguide 33a, passes through the optical fiber 21A, and enters the first O / E converter 23A from the optical circulator 16A. Then, the light enters the second O / E converter 23B from the optical circulator 16B through the optical fiber 21B. These O / E converters 23A and 23B generate electric signals obtained by converting the modulated light, and output the electric signals to the amplifiers 24A and 24B. The amplifiers 24A and 24B amplify the electrical signals output from the O / E converters 23A and 23B, and output the amplified electrical signals to the measuring device 13.

  The power detector 27A of the measuring device 13 converts the electrical signal output from the distributor 26A into the power level of the first existing antenna 39a, and outputs the converted power level to the computer 29. The power detection unit 27B converts the electrical signal output from the distributor 26B into the power level of the second existing antenna 39b, and outputs the converted power level to the computer 29. The central processing unit of the computer 29 stores the power levels of the first and second existing antennas 39a and 39b output from the power detection units 27A and 27B in the hard disk (second measurement means, second measurement step).

  After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the power level (c2−2) of the first existing antenna 39a after a predetermined period has elapsed since the installation of the antenna 39 output from the power detector 27A. 1) is stored in the hard disk in a state associated with the antenna identifier of the first existing antenna 39a, the sensor identifier of the first optical electric field sensor 12A, the level identifier, and the measurement date / time (year / month / day / hour). After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the power level (c2−2) of the second existing antenna 39b after a predetermined period has elapsed since the installation of the antenna 39 output from the power detector 27B. 2) is stored in the hard disk in a state associated with the antenna identifier of the second existing antenna 39b, the sensor identifier of the second optical electric field sensor 12B, the level identifier, and the measurement date / time (year / month / day / minute).

  The phase detector 28A of the measuring device 13 converts the electrical signal output from the distributor 26A into the phase of the first existing antenna 39a, and outputs the converted phase to the computer 29. The phase detection unit 28B converts the electrical signal output from the distributor 26B into the phase of the second existing antenna 39b, and outputs the converted phase to the computer 29. The computer 29 stores the phases of the first and second existing antennas 39a and 39b output from the phase detectors 28A and 28B in the hard disk (second measuring means, second measuring step).

  After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the phase (d2-1) of the first existing antenna 39a after a predetermined period has elapsed since the installation of the antenna 39 output from the phase detector 28A. ) Is stored in the hard disk in a state associated with the antenna identifier of the first existing antenna 39a, the sensor identifier of the first optical electric field sensor 12A, the phase identifier, and the measurement date (year / month / day / hour). After the second optical electric field sensor 12B is moved to the second existing antenna 39b, the phase (d2-2) of the second existing antenna 39b after the elapse of a predetermined period from the time of installation of the antenna 39 output from the phase detector 28B. ) Is stored in the hard disk in a state associated with the antenna identifier of the second existing antenna 39b, the sensor identifier of the second optical electric field sensor 12B, the phase identifier, and the measurement date (year / month / day / hour).

  The central processing unit of the computer 29 calculates the fourth phase difference (ph4) = (d2-1) − (d2-2) between the phase (d2-1) and the phase (d2-2), and the phase difference ( ph4) is stored in the hard disk. The fourth phase difference (ph4) is stored in the hard disk in a state associated with the antenna identifier, the phase identifier, and the measurement date (year / month / day / hour).

  The central processing unit of the computer 29 measures the power level (c1-1) of the first existing antenna 39a measured by the first measuring means (first measuring process), and the second measured by the first measuring means (first measuring process). By the power level (c1-2) of the existing antenna 39b, the power level (c2-1) of the first existing antenna 39a measured by the second measuring means (second measuring step), and by the second measuring means (second measuring step). Using the measured power level (c2-2) of the second existing antenna 39b, a second power ratio (ΔP2) (level comparison value) after a predetermined period has elapsed since the installation of the antenna 39 (level comparison value calculation means) , Level comparison value calculation step).

  Specifically, a first ratio having the power level (c1-1) as the denominator and the power level (c2-1) as the numerator is calculated, and the power level (c1-2) is set as the denominator. The second ratio with 2) as the numerator is calculated, and the first ratio {(c2-1) / (c1-1)} is used as the denominator, and the second ratio {(c2-2) / (c1-2) } As a numerator, the second power ratio (ΔP2) [%] = {(c2-2) / (c1-2)} / {(c2-1) / (c1-1)} is calculated. The central processing unit of the computer 29 stores the calculated power ratio (ΔP2) in the hard disk. The second power ratio (ΔP2) is stored in the hard disk in a state associated with the antenna identifier, the level identifier, and the measurement date / time (year / month / day / minute).

  The central processing unit of the computer 29 uses the third phase difference (ph3) and the fourth phase difference (ph4), and the second phase difference comparison value (ΔPh2) (phase difference comparison) after a predetermined period has elapsed since the installation of the antenna 39. Value) (phase difference comparison value calculation means, phase difference comparison value calculation step). Specifically, the phase difference (ph3) is subtracted from the phase difference (ph4) to calculate the second comparison phase difference (ΔPh2) [deg] = (ph4) − (ph3). The central processing unit of the computer 29 stores the calculated phase difference comparison value (ΔPh2) in the hard disk. The second phase difference comparison value (ΔPh2) is stored in the hard disk in a state associated with the antenna identifier, the phase identifier, and the measurement date (year / month / day / hour).

Although not described, the second optical electric field sensor 12B is installed in order from the third existing antenna 39c to the 16th existing antenna in a state where the first optical electric field sensor 12A is installed on the first existing antenna 39a. Measure the power level and phase of these existing antennas after a predetermined period from the installation of 39, calculate the power ratio (ΔP) and phase difference comparison value (ΔPh) after the predetermined period from the installation of the antenna 39, and calculate The power ratio (ΔP) and the phase difference comparison value (ΔPh) are stored in the hard disk of the computer 29.

  FIG. 15 is a diagram illustrating an example of the calculated power ratio (ΔP), and FIG. 16 is a diagram illustrating an example of the calculated phase difference comparison value (ΔPh). In FIG. 15, the power level (a1-1) before the movement of the sensor 12B when the antenna 39 is installed and the sensors 12A and 12B are installed on the antenna 39a is 100, and the sensor 12A and 12B is installed on the antenna 39a when the antenna 39 is installed. The power level (a1-2) before moving the sensor 12B installed at 100 is 100 and the antenna 39 is installed, and the power level (a2-1) after moving the sensor 12B to the antenna 39b is 101 and when the antenna 39 is installed. The power level (a2-2) after moving the sensor 12B to the antenna 39b is 51, and the first power ratio (ΔP1) [%] = {(a2-2) / (a1-2)} / { (A2-1) / (a1-1)} × 100 = {51/100} / {101/100} × 100 = 50.5 [%].

  The power level (c1-1) before the movement of the sensor 12B when the sensors 12A and 12B are installed on the antenna 39a is 100 after the predetermined time has elapsed since the installation of the antenna 39, and after the predetermined time has elapsed since the installation of the antenna 39. The power level (c1-2) before moving the sensor 12B with the sensors 12A and 12B installed on the antenna 39a is 100, and the power level after moving the sensor 12B to the antenna 39b after a predetermined time has elapsed since the installation of the antenna 39. (C2-1) is 101, the power level (c2-2) after moving a sensor 12B to the antenna 39b after a predetermined time has elapsed from the time of installation of the antenna 39 is 49, and the second power ratio (ΔP2) [ %] = {(C2-2) / (c1-2)} / {(c2-1) / (c1-1)} × 100 = {49/100} / {101/100} × 00 = is 48.5.

  The central processing unit of the computer 29 compares the first power ratio (ΔP1) [%] with the second power ratio (ΔP2) [%], and the difference between these power ratios is within an allowable range (± α [%]) = It is determined whether it is within ± 5 [%] (level comparison means, level comparison step). Since the difference between the first power ratio (ΔP1) [%] and the second power ratio (ΔP2) [%] is +2 [%] and the difference in power ratio is within the allowable range, the central processing unit of the computer 29 Determines that there is no abnormality in the first and second existing antennas 39a and 39b, and displays an antenna normality message on the display. Conversely, if the difference in power ratio is outside the allowable range, the central processing unit of the computer 29 determines that the first and second existing antennas 39a and 39b are abnormal and displays an antenna abnormality message on the display. .

In FIG. 16, the first phase difference (ph1) before the movement of the sensor 12B when the antenna 39 is installed and the sensors 12A and 12B are installed on the antenna 39a is 0, and the sensor 12B is installed on the antenna 39b when the antenna 39 is installed. the installed second phase difference after the sensor 12B move (ph2) is 60, the first phase difference comparison value (ΔPh1) [deg] = ( ph2) - a (ph1) = 60 [deg] .

The third phase difference (ph3) before the movement of the sensor 12B in which the sensors 12A and 12B are installed on the antenna 39a is 0 after the predetermined time has elapsed since the installation of the antenna 39, and after the predetermined time has elapsed since the installation of the antenna 39. a fourth phase difference after sensor 12B movement sensor 12B is installed in the antenna 39b by (ph4) is 58, the second phase difference comparison value (ΔPh2) [deg] = ( ph4) - (ph3) = 58 [deg ].

  The central processing unit of the computer 29 compares the first phase difference comparison value (ΔPh1) [deg] with the second phase difference comparison value (ΔPh2) [deg], and the difference between the phase difference comparison values is within an allowable range (± It is determined whether β [deg]) = ± 10 [deg] (phase difference comparison means, phase difference comparison step). The difference between the first phase difference comparison value (ΔPh1) [deg] and the second phase difference comparison value (ΔPh2) [deg] is +2 [deg], and the difference between these phase difference comparison values is within the allowable range. The central processing unit of the computer 29 determines that there is no abnormality in the first and second existing antennas 39a and 39b, and displays an antenna normality message on the display. On the contrary, when the difference of the phase difference comparison value is out of the allowable range, the central processing unit of the computer 29 determines that the first and second existing antennas 39a and 39b are abnormal, and displays an antenna abnormality message on the display. indicate.

  Although not described, the power ratio (ΔP) illustrated in FIG. 15 and the phase difference comparison value (ΔPh) illustrated in FIG. 16 are calculated for the third existing antenna 39c to the sixteenth existing antenna, and the power It is judged whether the difference in the ratio is within an allowable range (± α [%]) (level comparison means, level comparison process), and whether the difference in the phase difference comparison value is within the allowable range (± β [%]) Judgment is made (phase difference comparison means, phase difference comparison step), and an antenna normal message and an antenna abnormality message of the third existing antenna 39c to the sixteenth existing antenna are displayed on the display.

  The characteristic measurement system 10 (characteristic measurement method) simultaneously measures the power level and phase difference of the first existing antenna 39a using the modulated light emitted from the first and second optical electric field sensors 12a and 12b, and the first existing antenna 39a. The second optical electric field sensor 12B removed from the first existing antenna 30a is sequentially installed on the second to sixteen existing antennas while maintaining the installation state of the first optical electric field sensor 12A with respect to the optical field sensors 12A, 12B. The power level and phase difference in the existing antennas are simultaneously measured by the modulated light emitted from the power source, and the power level and phase difference measured by the first measuring means (first measuring step) and the second measuring means (second measuring step) ) To calculate the power ratio (level comparison value) and phase difference comparison value from the power level and phase difference measured by Therefore, it is possible to prevent variations in level and phase difference due to measurement of the power level and phase difference after the environmental change around the antenna at different times, and the accurate power ratio (ΔP) of these existing antennas (level comparison value) And an accurate phase difference comparison value can be calculated.

  The characteristic measurement system 10 (characteristic measurement method) obtains the power ratio (ΔP) (level comparison value) of these existing antennas when the antenna 39 is installed or before the antenna 39 is installed, and is calculated after a predetermined period from the installation of the antenna 39. The power ratio (ΔP) (level comparison value) obtained is compared with the power ratio (ΔP) obtained when the antenna 39 is installed or before the antenna 39 is installed, and the power ratio (ΔP) (level is obtained when the antenna 39 is installed or before the antenna 39 is installed. If the difference in power ratio (ΔP) (level comparison value) calculated after the lapse of a predetermined period from the time of installation with respect to the comparison value) is out of the allowable range, failure or malfunction of the existing antennas after the lapse of the predetermined period from the installation of the antenna It can be determined that an abnormality such as the above has occurred, and the abnormality of the existing antenna can be accurately grasped.

  The characteristic measurement system 10 (characteristic measurement method) includes a power ratio (ΔP) (level comparison value) obtained when the antenna 39 is installed or before installation, and a power ratio (ΔP) (level comparison value) calculated after a predetermined period from the installation. ), It is possible to determine abnormalities such as failures and malfunctions of those existing antennas, so it is possible to quickly find any malfunctions or malfunctions of those existing antennas, An existing antenna in which an abnormality has occurred can be repaired and replaced quickly, and the influence on other normal existing antennas can be minimized.

  The characteristic measurement system 10 (characteristic measurement method) obtains the phase difference comparison value (ΔPh) of the existing antennas when the antenna 39 is installed or before the antenna 39 is installed, and the phase difference calculated after a predetermined period has elapsed since the antenna 39 was installed. The comparison value (ΔPh) is compared with the phase difference comparison value calculation (ΔPh) obtained when the antenna 39 is installed or before the antenna 39 is installed, and the phase difference comparison value (ΔPh) obtained when the antenna 39 is installed or before the installation is installed. If the difference of the phase difference comparison value (ΔPh) calculated after the elapse of a predetermined period of time is out of the allowable range, it is determined that an abnormality such as a failure or a malfunction has occurred in the existing antennas after the elapse of the predetermined period from the time of antenna installation. Therefore, it is possible to accurately grasp the abnormality of the existing antennas.

  The characteristic measurement system 10 (characteristic measurement method) compares the phase difference comparison value (ΔPh) obtained when the antenna 39 is installed or before installation with the phase difference comparison value (ΔPh) calculated after a predetermined period from the installation. Therefore, it is possible to grasp abnormalities such as failures and malfunctions of these existing antennas, so it is possible to quickly find any malfunctions or malfunctions of those existing antennas, and the existing antenna where those abnormalities have occurred Can be promptly repaired and replaced, and the influence on other normal existing antennas can be minimized.

  In the characteristic measurement system 10 (characteristic measurement method), the installation positions of the first and second optical electric field sensors 12A and 12B with respect to the physical center 40 of the first existing antenna 39a are at substantially equal distances. , 12B have the same measurement conditions for the power level and the phase difference, and the power level and the phase difference measured using the modulated light emitted from the optical electric field sensors 12A, 12B may vary due to the difference in the measurement conditions. The accurate electric power level and the accurate phase difference of the first existing antenna 39a can be measured using the optical electric field sensors 12A and 12B.

  In the characteristic measurement system 10 (characteristic measurement method), the installation position of the first optical electric field sensor 12A with respect to the first existing antenna 39a and the installation position of the second optical electric field sensor 12B with respect to the second existing antenna 39b are substantially the same. The measurement conditions of the power level and the phase difference in the optical electric field sensors 12A and 12B are the same, and the power level and the phase difference measured using the modulated light emitted from the optical electric field sensors 12A and 12B depend on the difference in the measurement conditions. There is no variation, and it is possible to measure the accurate power level and the accurate phase of the existing antennas 39a and 39b using the optical electric field sensors 12A and 12B.

  The characteristic measurement system 10 (characteristic measurement method) transmits the modulated light emitted from the second optical electric field sensor 12B with respect to the length of the first optical fiber 21A that transmits the modulated light emitted from the first optical electric field sensor 12A. The length of the first optical fiber 21A is such that the path difference in the length of the second optical fiber 21B is within an appropriate range in which the phase can be accurately measured with respect to changes in the temperature environment at the time of phase measurement. In contrast, since the length of the second optical fiber 21B is adjusted, the lengths of the optical fibers 21A and 21B extending from the first and second optical electric field sensors 12A and 12B and transmitting phase data are measured. Even if the phase measured by using the optical electric field sensors 12A and 12B changes due to the temperature environment, the measurement is performed by using the first optical electric field sensor 12A. It can be easily proved that the phase deviation measured using the second optical electric field sensor 12B approximates the phase deviation, and the optical electric field sensors 12A and 12B are used. The phase of these existing antennas can be measured with high reliability.

  In the characteristic measurement system 10 (characteristic measurement method), the path difference (ΔL) is calculated by the equation: ΔL ≦ ΔPh / (0.0576 × Frq × ΔT), and the first and second photoelectric elements are used by using the equation. Since the phase shift amount (ΔPh) measured using the field sensors 12A and 12B is set in an allowable range, the length of each of the optical fibers 21A and 21B can be obtained based on the allowable range. When determining the phase of the optical fibers 21A and 21B, the lengths of the optical fibers 21A and 21B can be adjusted so that the path difference between the optical fibers 21A and 21B is within an appropriate range.

DESCRIPTION OF SYMBOLS 10 Characteristic measurement system 11 Transmission / reception apparatus 12A 1st optical electric field sensor 12B 2nd optical electric field sensor 13 Measuring apparatus 14 Optical transmission part 15 Optical reception part 16A Optical circulator 16B Optical circulator 17 Light source for optical modulator 18 Polarization synthesizer 19 Optical coupler 20 Polarization-maintaining optical fiber 21 Single mode optical fiber 22A First light source for optical modulator 22B Second light source for optical modulator 23A First O / E converter 23B Second O / E converter 24A First amplifier 24B Second amplifier 26A Divider 26B Distributor 27A Power detector 27B Power detector 28A Phase detector 28B Phase detector 29 Computer 30 Housing 31 Optical modulator 32 Single crystal substrate (substrate)
33 Mach-Zehnder type optical waveguide (optical waveguide)
33a Input / output optical waveguide 33b Phase shift optical waveguide 33c Phase shift optical waveguide 34 Buffer layer 35 Antenna 35a Extension part 35b Extension part 35c Extension part 37 Light reflection part 39 Antenna 40 Center

Claims (16)

An optical electric field sensor that is installed in an antenna to be measured and modulates the intensity of input light in accordance with the electric field intensity of an electromagnetic wave transmitted from the antenna, and emits modulated light obtained by modulating the input light; and the optical electric field sensor A light source that emits the input light; and an O / E converter that converts the modulated light emitted from the optical electric field sensor into an electrical signal, based on the electrical signal output from the O / E converter. In an antenna characteristic measurement system using an optical electric field sensor for measuring antenna performance, the antenna to be measured is a plurality of first to n-th existing antennas having the same power level or different power levels, the same phase or different phases. And the optical electric field sensor is formed of a first optical electric field sensor and a second optical electric field sensor which are detachably installed at predetermined positions of the first to n-th existing antennas. And
The system, first the first and second optical electric field sensor is installed in the first existing antenna, simultaneously measures the power level and the phase difference of the first existing antenna by modulating light emitted from these light field sensor 1 and measuring means, said with installation state is maintained of the first optical electric field sensor with respect to the first existing antenna, the first and the second optical electric field sensor which has been removed from the existing antenna the second to n existing antenna to be installed in order, and a second measuring means for simultaneously measuring the power level and the phase difference in their existing antennas by modulating light emitted from these light field sensor, the second measurement was the power level measured by said first measuring means Level comparison value calculation means for calculating a level comparison value from the power level measured by the means, and the first measurement means. And a phase difference comparison value calculating means for calculating a phase difference comparison value from the phase difference measured by the second measuring means and the phase difference measured by the second measuring means. .   The system compares the level comparison value calculated by the level comparison value calculation means after the elapse of a predetermined period from the time of antenna installation or the level comparison value calculated by the level comparison value calculation means at the time of antenna installation or before the antenna installation. 2. The antenna characteristic measurement system using an optical electric field sensor according to claim 1, further comprising level comparison means for comparing the level comparison values in the design of these existing antennas.   The level comparison value calculated by the level comparison value calculation means uses the power level of the first existing antenna measured by the first measurement means as a denominator, and the power of the first existing antenna measured by the second measurement means. While calculating the 1st ratio which makes a level a numerator, the power level of the said 2nd-nth existing antenna measured by the said 1st measurement means is made into a denominator, and the said 2nd-nth measured by the said 2nd measurement means 3. The photoelectric device according to claim 1, wherein the second power ratio is a power ratio calculated using the first ratio as a denominator and the second ratio as a numerator after calculating a second ratio using a power level of an existing antenna as a numerator. Antenna characteristic measurement system using a field sensor.   The system compares the phase difference comparison value calculated by the phase difference comparison value calculation means after the elapse of a predetermined period from the time of antenna installation, before the phase difference comparison value calculated by the phase difference comparison value calculation means at the time of antenna installation or before the antenna installation. 4. The antenna characteristic measurement system using the optical electric field sensor according to claim 1, further comprising phase difference comparison means for comparing with a phase difference comparison value in the design of the existing antennas calculated in advance.   The phase difference comparison value calculated by the phase difference comparison value calculation means is the value of the second to nth existing antennas measured by the first measurement means from the phase of the first existing antenna measured by the first measurement means. The first phase difference obtained by subtracting the phase is calculated, and the phases of the second to n-th existing antennas measured by the second measuring unit are subtracted from the phases of the first existing antennas measured by the second measuring unit. 5. The antenna characteristic measurement system using an optical electric field sensor according to claim 1, wherein the phase difference is obtained by subtracting the first phase difference from the second phase difference after calculating the second phase difference. .   2. The system according to claim 1, wherein an installation position of the first and second optical electric field sensors with respect to the first existing antenna in the first measurement unit is substantially equal to a physical center of the first existing antenna. An antenna characteristic measurement system using the optical electric field sensor according to claim 5.   In the system, the first to n-th existing antennas have substantially the same shape, the installation position of the first optical electric field sensor with respect to the first existing antenna in the first measurement means, and the second measurement means in the second measurement means. The antenna characteristic measurement system using the optical electric field sensor according to any one of claims 1 to 6, wherein an installation position of the optical electric field sensor with respect to the second to n-th existing antennas is substantially the same.   In the system, the second optical fiber transmitting the modulated light emitted from the second optical electric field sensor with respect to the length (L1) of the first optical fiber transmitting the modulated light emitted from the first optical electric field sensor. The path difference (ΔL) (L1−L2) of the length (L2) is within an appropriate range in which the phase can be accurately measured with respect to a change in temperature environment at the time of the phase measurement. The length (L2) of the second optical fiber is adjusted with respect to the length (L1) of the first optical fiber, and the path difference (ΔL) is expressed by the equation: ΔL ≦ ΔPh / (0.0576 × Frq × ΔT (ΔL = path difference [m], ΔPh = phase difference [deg], Frq = frequency of electromagnetic waves [GHz], ΔT = temperature fluctuation range during measurement [° C.], 0.0576 = phase coefficient [ deg / GHz · ° C · m]) claims 1 to Antenna characteristic measurement system using an optical electric field sensor according to claim 7 or. An optical electric field sensor that is installed in an antenna to be measured and modulates the intensity of input light in accordance with the electric field intensity of an electromagnetic wave transmitted from the antenna, and emits modulated light obtained by modulating the input light; and the optical electric field sensor A light source that emits the input light; and an O / E converter that converts the modulated light emitted from the optical electric field sensor into an electrical signal, based on the electrical signal output from the O / E converter. In the antenna characteristic measurement method using the optical electric field sensor for measuring the performance of the antenna,
In the method, the antenna to be measured is a plurality of first to n-th existing antennas having the same power level or different power levels, the same phase or different phases, and the optical electric field sensor is the first to n-th existing antennas. Formed from a first optical electric field sensor and a second optical electric field sensor which are detachably installed at a predetermined position of
In the method, the first and second optical electric field sensors are installed on the first existing antenna, and the power level and the phase difference of the first existing antenna are simultaneously measured by the modulated light emitted from the optical electric field sensors. One measurement step and the second optical field sensor removed from the first existing antenna in order to the second to nth existing antennas while maintaining the installation state of the first optical field sensor with respect to the first existing antenna. And a second measurement step of simultaneously measuring the power level and the phase difference in the existing antennas by the modulated light emitted from the optical electric field sensors, the power level measured by the first measurement step, and the second measurement step. A level comparison value calculation step for calculating a level comparison value from the measured power level, and a phase difference measured by the first measurement step Characteristic measuring method of the antenna using the optical electric field sensor characterized by having a phase difference comparison value calculation step for calculating a phase difference comparison value from the phase difference measured by the second measuring step.   In the method, the level comparison value calculated by the level comparison value calculation step after the elapse of a predetermined period from the time of installation of the antenna is calculated in advance before the level comparison value calculated by the level comparison value calculation step at the time of antenna installation or before the antenna installation. The method for measuring antenna characteristics using an optical electric field sensor according to claim 9, further comprising a level comparison step for comparing with a design level comparison value calculation of the existing antennas.   The level comparison value calculated in the level comparison value calculation step uses the power level of the first existing antenna measured in the first measurement step as a denominator, and the power of the first existing antenna measured in the second measurement step. While calculating the 1st ratio which makes a level a numerator, the electric power level of the said 2nd-nth existing antenna measured by the said 1st measurement process is made into a denominator, and the said 2nd-nth measured by the said 2nd measurement process. 11. The photoelectric ratio according to claim 9, wherein the second power ratio is a power ratio calculated using the first ratio as a denominator and the second ratio as a numerator after calculating a second ratio using a power level of an existing antenna as a numerator. Antenna characteristic measurement method using field sensor.   In the method, the phase difference comparison value calculated by the phase difference comparison value calculation step after the elapse of a predetermined period from the time of antenna installation is compared with the phase difference comparison value calculated by the phase difference comparison value calculation step at the time of antenna installation or before the antenna installation. 12. A method for measuring antenna characteristics using an optical electric field sensor according to claim 9, further comprising a phase difference comparison step for comparing with a previously calculated phase difference comparison value calculation for existing antennas.   The phase difference comparison value calculated in the phase difference comparison value calculation step is determined based on the second to n-th existing antennas measured in the first measurement step from the phase of the first existing antenna measured in the first measurement step. The first phase difference obtained by subtracting the phase is calculated, and the phases of the second to n-th existing antennas measured by the second measurement step are subtracted from the phases of the first existing antennas measured by the second measurement step. 13. The method for measuring antenna characteristics using an optical electric field sensor according to claim 9, wherein the phase difference is obtained by subtracting the first phase difference from the second phase difference after calculating the second phase difference. .   In the method, the installation positions of the first and second optical electric field sensors with respect to the first existing antenna in the first measurement step are substantially equal to the physical center of the first existing antenna. An antenna characteristic measurement method using the optical electric field sensor according to claim 13.   In the method, the shapes of the first to n-th existing antennas are substantially the same, the installation position of the first optical electric field sensor in the first measurement step with respect to the first existing antenna and the second in the second measurement step. The method for measuring antenna characteristics using an optical electric field sensor according to any one of claims 9 to 14, wherein an installation position of the optical electric field sensor with respect to the second to n-th existing antennas is substantially the same.   In the method, the length of the second optical fiber that transmits the modulated light emitted from the second optical electric field sensor with respect to the length (L1) of the first optical fiber that transmits the modulated light emitted from the first optical electric field sensor. The path difference (ΔL) (L1−L2) of the length (L2) is within an appropriate range in which the phase can be accurately measured with respect to a change in temperature environment during the phase measurement. The length (L2) of the second optical fiber is adjusted with respect to the length (L1) of one optical fiber, and the path difference (ΔL) is expressed by the equation: ΔL ≦ ΔPh / (0.0576 × Frq × ΔT) (ΔL = path difference [m], ΔPh = phase difference [deg], Frq = frequency of electromagnetic wave [GHz], ΔT = temperature fluctuation range during measurement [° C.], 0.0576 = phase coefficient [deg / GHz · ° C. · m])) Characteristic measuring method of the antenna using the optical electric field sensor according to any misalignment.

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