JP7329564B2 - Measurement system and measurement method for antenna directivity characteristics of wireless terminal - Google Patents

Description

The present invention relates to a technology for measuring directivity characteristics of antennas of wireless terminals such as mobile phones, smart phones, tablets, and wireless routers.

When a wireless terminal such as a mobile phone or a data communication terminal is developed, it is necessary to test whether or not the developed wireless terminal can perform communication normally. For this reason, a test in which a wireless terminal under test is connected to a test device that operates as a pseudo base station that simulates the functions of an actual base station, communication is performed between the test device and the wireless terminal, and the contents of communication are confirmed. are doing

As such a test, there is a conformance test for checking whether a wireless terminal compatible with 5G NR (New Radio) conforms to the 3GPP (3rd Generation Partnership Project) standard. The conformance test method is also specified in detail by 3GPP, and it is necessary to perform measurements that meet the specified requirements.

For example, in a conformance test for FR2 (Frequency Range 2), in an OTA (Over The Air) test environment, a wireless terminal to be tested is installed in a positioner capable of controlling its attitude, and transmission and reception of the wireless terminal are performed while changing the attitude of the wireless terminal. Characteristics are measured (see, for example, Patent Document 1). A directional antenna, such as an array antenna, is used as the terminal antenna provided in the wireless terminal under test, and the measured transmission/reception characteristics depend on the attitude (orientation or direction). Therefore, the conditions for the directivity of the terminal antenna are also specified in the conformance test.

Specifically, in a conformance test according to the technical specifications of 3GPP, it is necessary to find a placement direction of a wireless terminal or a terminal antenna that satisfies the conditions described in the technical specifications (for example, see Non-Patent Document 1). For example, there must be at least 12 dB isolation for each of the two TE polarization branches, and the rank reported by the wireless terminal must be equal to or greater than the predetermined rank specified in the test. is required. In this conformance test, after arranging the terminal antenna directly facing the measurement antenna so as to satisfy these specified conditions, specific test contents are carried out.

Japanese Patent Application Laid-Open No. 2018-189601

3GPP TS 38.521-4 "Procedure for finding UE direction" in annex H.0 and H.1

As described above, the antenna setup for conformance tests specified by 3GPP requires that the measurement antenna and the terminal antenna face each other, and that the isolation between the horizontal and vertical polarized waves of the terminal antenna is sufficiently ensured. there is In practice, the terminal antennas arranged in the positioner may have a vertically polarized antenna pointing in a first direction different from the vertical direction, and a horizontally polarized antenna pointing in a second direction different from the horizontal direction. . For this reason, the isolation between the horizontal and vertical polarizations of the terminal antenna is referred to as orthogonal polarization isolation (or interpolar isolation).

However, in a conventional measurement system such as that described in Patent Document 1, in order to confirm that the isolation between orthogonal polarizations is equal to or greater than a desired value, the terminal antenna of the wireless terminal must be positioned within a plane perpendicular to the direction of radio wave propagation. It is necessary to mechanically rotate 90° and confirm that the received power is minimized (difference in received power is 12 dB or more).

Mechanically rotating the wireless terminal to measure the orthogonal polarization isolation of the terminal antenna takes time, which increases the time required to set up the test.

SUMMARY OF THE INVENTION The present invention has been made to solve such conventional problems, and provides an antenna directivity device capable of quickly measuring the directivity characteristics of an antenna of a wireless terminal capable of ensuring the required isolation between orthogonal polarized waves. An object of the present invention is to provide a characteristic measurement system and a measurement method.

An antenna directivity measurement system of the present invention is an antenna directivity measurement system (1) for measuring the directivity of a terminal antenna provided in a wireless terminal, the measurement antenna transmitting and receiving radio waves with the terminal antenna. (20) transmitting a polarized wave signal including a vertically polarized wave signal and a horizontally polarized wave signal to the wireless terminal as a test signal via the measurement antenna, and measuring the test signal received by the wireless terminal at the terminal antenna; a transmitter/receiver (40) for receiving a response signal including power value information from the terminal antenna via the measurement antenna; and a detector for detecting the power value of the test signal from the response signal received by the transmitter/receiver. a section (31) changing the amplitude ratio and the phase difference between the vertical polarization signal and the horizontal polarization signal to shift the plane of polarization of the test signal to 90° around the axis (Z), which is the traveling direction of radio waves; An electrical phase rotation control unit (333) that causes the transmitting/receiving unit to generate a linearly polarized signal obtained by rotation, and transmits the generated linearly polarized signal as a test signal from the measurement antenna and detects it by the detection unit. whether the difference between the power value of the linearly polarized wave signal received by the terminal antenna and the power value detected when using the original test signal before rotating the plane of polarization by 90° is greater than or equal to a predetermined threshold a terminal rotation mechanism (10) that holds and rotates the wireless terminal to change the position of the wireless terminal; and associates the detected power value with the position of the wireless terminal. and a maximum determination unit (332) that determines whether or not there is a maximum power value at any position of the wireless terminal stored in the storage unit, In the isolation determination section, if there is a maximum power value, the electrical phase rotation control section changes the amplitude ratio and phase difference between the vertical polarization signal and the horizontal polarization signal to determine the maximum power value. causing the transmitting/receiving unit to generate a linearly polarized wave signal obtained by rotating the plane of polarization of the test signal used when obtaining the maximum power value at 90° about the direction of radio wave propagation, The generated linearly polarized signal is transmitted as a test signal from the measurement antenna, and the difference between the power value of the linearly polarized signal received by the terminal antenna detected by the detection unit and the maximum power value is the It is determined whether or not it is equal to or greater than a predetermined threshold , and the transmission/reception unit includes a first phase shifter (41) that phase-shifts the vertical polarization and a second phase shifter (42) that phase-shifts the horizontal polarization. ), and the electrical phase rotation control section, when it is determined by the maximum determination section that there is no maximum power value, changes the vertical polarization signal and the horizontal polarization signal constituting the test signal to be transmitted. It is characterized by changing at least one of the respective amplitudes (AV, AH) and phase difference (δ) .

As described above, in the antenna directivity measurement system of the present invention, the isolation judging unit tests a linearly polarized wave signal obtained by rotating the plane of polarization of the test signal by 90° about the direction of radio wave propagation. When using the power value of the linearly polarized signal received by the terminal antenna, which is generated as a signal, transmitted from the measurement antenna, and detected by the detection unit, and the original test signal before the plane of polarization is rotated by 90°, the detection unit determines whether or not the difference from the detected power value is equal to or greater than a predetermined threshold value. With this configuration, the plane of polarization of the test signal to be transmitted is rotated by 90° without actually mechanically rotating the wireless terminal by 90°, and the difference in the power value of the test signal received by the terminal antenna before and after rotation is used. can confirm the isolation between orthogonal polarizations at the terminal antenna. As a result, it is not necessary to actually rotate the wireless terminal to check the isolation, so the time required to measure the directivity characteristics of the wireless terminal can be greatly reduced.

The antenna directivity measurement system of the present invention includes a terminal rotation mechanism (10) that holds and rotates the wireless terminal and changes the position of the wireless terminal, and stores the detected power value in association with the position of the wireless terminal. a storage unit (32); and a maximum determination unit (332) for determining whether or not there is a maximum power value at any position of the wireless terminal stored in the storage unit. If there is a maximum power value, the electrical phase rotation control unit changes the amplitude ratio between the vertical polarization signal and the horizontal polarization signal to determine the maximum power value at the maximum. The transmitting/receiving unit is caused to generate a linearly polarized wave signal obtained by rotating the plane of polarization of the test signal used when acquiring the radio wave traveling direction by 90° around the axis, and the generated linearly polarized wave A signal is transmitted from the measurement antenna as a test signal, and the difference between the power value of the linearly polarized signal received by the terminal antenna detected by the detection unit and the maximum power value is the predetermined threshold. The configuration may be such that it is determined whether or not there is more than the above.

With this configuration, the antenna directivity measurement system of the present invention can identify the position (θ, φ) of the wireless terminal at which the required orthogonal polarization isolation can be secured in the terminal antenna. That is, it is possible to obtain accurate information on the position of the wireless terminal in which the measurement antenna and the terminal antenna face each other.

In the antenna directivity measurement system of the present invention, the response signal is the power value of the polarization component in the first direction of the test signal received by the terminal antenna of the wireless terminal and the power value of the polarization component in the second direction orthogonal to the first direction. the detection unit detects the power values of the polarization components in the first direction and the second direction from the response signal received by the transmission/reception unit, and the isolation The determination unit may determine whether or not the detected difference in power values in the first direction and the detected difference in power values in the second direction are equal to or greater than the predetermined threshold.

With this configuration, in the antenna directivity measurement system of the present invention, the isolation determination unit performs determination for each of the first direction and the second direction, so that the isolation between orthogonal polarized waves of the terminal antenna can be determined more accurately. can.

In the antenna directivity measurement system of the present invention, the transmission/reception unit includes a first phase shifter (41) for phase-shifting the vertical polarization and a second phase shifter (42) for phase-shifting the horizontal polarization. and the electrical phase rotation control unit, when the maximum determination unit determines that there is no maximum power value, each of the vertically polarized wave signal and the horizontally polarized wave signal constituting the test signal to be transmitted At least one of the amplitudes (AV, AH) and the phase difference (δ) may be changed .

With this configuration, the antenna directivity measurement system of the present invention can be used not only when the terminal antenna rotates around the direction of propagation of radio waves (Z-axis), but also when the terminal antenna rotates around the axis (for example, the Y-axis). ) even if the terminal antenna is rotating around, it is possible to accurately determine the presence of a maximum received power value at the terminal antenna, thereby more accurately identifying the direction of the terminal antenna. can.

In the antenna directivity measurement system of the present invention, the electrical phase rotation control unit configures a test signal to be transmitted when the isolation determination unit determines that the difference in power values is smaller than the predetermined threshold. At least one of the amplitude (AV, AH) and the phase difference (δ) of each of the vertical polarization signal and the horizontal polarization signal may be further changed.

With this configuration, the antenna directivity measurement system of the present invention can be used not only when the terminal antenna rotates around the direction of propagation of radio waves (Z-axis), but also when the terminal antenna rotates around the axis (for example, the Y-axis). ), the orthogonal cross-polarization isolation of the terminal antenna can be accurately determined even when the terminal antenna is rotated around, thereby more accurately determining the orientation of the terminal antenna.

The antenna directivity measurement system of the present invention includes a mechanical rotation control unit (334) that changes the position of the wireless terminal by the terminal rotation mechanism when the maximum determination unit determines that there is no maximum power value. It may be a configuration further comprising.

With this configuration, the antenna directivity measurement system of the present invention can accurately determine the presence of a maximum received power value at the terminal antenna, thereby allowing the antenna to be measured and It is possible to search for a candidate position where the terminal antenna faces directly.

In the antenna directivity measurement system of the present invention, the mechanical rotation control unit causes the terminal rotation mechanism to rotate the wireless terminal when the isolation determination unit determines that the difference in power values is smaller than the predetermined threshold. may be configured to further change the position of .

With this configuration, the antenna directivity measurement system of the present invention can accurately determine the isolation between orthogonal polarizations of the terminal antenna, thereby allowing the antenna to be measured and the terminal antenna to move beyond the electrically rotatable range. Candidate positions facing each other can be found.

In the antenna directivity measurement system of the present invention, the maximum determination unit determines that there is a maximum value of the power of the test signal received by the terminal antenna, and the isolation determination unit rotates the polarization plane by 90°. The configuration may further include a display unit (36) that displays the position of the wireless terminal as a candidate position for the test when it is determined that the difference between the power values of the detected test signals is greater than or equal to the predetermined threshold. good.

With this configuration, the antenna directivity measurement system of the present invention allows the user to confirm test candidate positions.

An antenna directivity measuring method according to the present invention is a method for measuring directivity of a terminal antenna provided in a wireless terminal, comprising a terminal rotating step of holding and rotating the wireless terminal and changing the position of the wireless terminal. a transmission step of transmitting a polarized signal including a vertically polarized signal and a horizontally polarized signal as a test signal from a measurement antenna to the wireless terminal; and a first direction of the test signal received by the wireless terminal at the terminal antenna. a receiving step of receiving, from the terminal antenna via the measurement antenna, a response signal containing information on the power value of the polarization component of and the power value of the polarization component in the second direction orthogonal to the first direction; a detecting step of detecting power values of the polarization components in the first direction and the second direction from the received response signal; and a storing step of storing the detected power values in association with the position of the wireless terminal. and a maximum determination step of determining whether or not the maximum power value exists at any position of the stored wireless terminal; and if the maximum power value exists, the vertically polarized signal and the By changing the amplitude ratio of the horizontally polarized signal, the plane of polarization of the test signal used when obtaining the maximum power value at the maximum was obtained by rotating the plane of polarization of the test signal by 90° around the axis of the direction of radio wave propagation. and transmits the generated linearly polarized signal as a test signal from the measurement antenna, and detects the linearly polarized signal received by the terminal antenna in the detecting step. The difference between the power value in one direction and the maximum power value in the first direction, the power value in the second direction of the linearly polarized signal received by the terminal antenna, and the maximum power value in the second direction and an isolation judgment step of judging whether or not the difference between .

As described above, in the method for measuring antenna directivity characteristics of the present invention, in the isolation determination step, a linearly polarized wave signal obtained by rotating the plane of polarization of a test signal by 90° about the direction of propagation of radio waves is tested. When using the power value of the linearly polarized signal received by the terminal antenna, which is generated as a signal and transmitted from the measurement antenna and detected in the detection step, and the original test signal before the plane of polarization is rotated by 90° in the detection step It is determined whether or not the difference from the detected power value is equal to or greater than a predetermined threshold. With this configuration, the plane of polarization of the test signal to be transmitted is rotated by 90° without actually mechanically rotating the wireless terminal by 90°, and the difference in the power value of the test signal received by the terminal antenna before and after rotation is used. can confirm the isolation between orthogonal polarizations at the terminal antenna. As a result, it is not necessary to actually rotate the wireless terminal to check the isolation, so the time required to measure the directivity characteristics of the wireless terminal can be greatly reduced.

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to provide an antenna directivity measuring system and a measuring method capable of rapidly measuring the directivity of an antenna of a wireless terminal capable of ensuring the required orthogonal inter-polarization isolation.

1 is a diagram showing an overall schematic configuration of an antenna directivity measurement system according to an embodiment of the present invention; FIG. It is a figure for demonstrating a coordinate system. FIG. 4 is a diagram showing a state in which a terminal antenna faces a measurement antenna; FIG. 4 is a diagram for explaining angular deviation of a terminal antenna; FIG. 10 is a diagram showing a coupling example on an Rx projection plane equivalent to Tx circular polarization; FIG. 4 is a diagram for explaining the relationship between the phase difference between vertically polarized waves and horizontally polarized waves and the angular deviation of terminal antennas; It is a figure for demonstrating the characteristic of this invention. 1 is a diagram showing an overall schematic configuration of an antenna directivity measuring apparatus according to an embodiment of the present invention; FIG. 3 is a block diagram showing an outline of functions of a control unit; FIG. 4 is a flowchart for explaining the purpose of the antenna directivity measurement method according to the present embodiment; 4 is a flowchart showing an outline of an antenna directivity measurement method according to the present embodiment; 4 is a flowchart showing an outline of power measurement processing; It is a flowchart which shows the outline of a result display process.

An antenna directivity measurement system and measurement method according to embodiments of the present invention will be described below with reference to the drawings.

(Antenna directivity measurement system)
FIG. 1 is a diagram showing an overall schematic configuration of an antenna directivity measurement system 1 according to an embodiment of the present invention. As shown in FIG. 1, an antenna directivity measurement system 1 is a system for measuring the directivity of a terminal antenna 3 provided in a wireless terminal 2. A positioner 10 as a terminal rotation mechanism, a measurement antenna 20, and an antenna directivity measurement system are provided. 30.

The measurement antenna 20 transmits and receives radio waves to and from the terminal antenna 3 . Specifically, the measurement antenna 20 transmits a test signal including a vertically polarized signal and a horizontally polarized signal to the terminal antenna 3, and receives a response signal, which is a polarized signal, from the terminal antenna 3. there is The measurement antenna 20 is an antenna with a known directional characteristic that is fixed at a predetermined position in a measurement space, for example, inside an anechoic box (not shown) in which incoming radio waves from the outside and reflection of radio waves inside are suppressed. Antenna 3 is an antenna with unknown directional characteristics that is similarly held by a positioner 10 in the measurement space. In the millimeter wave band test, various types of antennas such as a horn antenna as shown in FIG. can be done.

Examples of measurement targets include wireless terminals such as mobile phones, smartphones, tablets, wireless routers, etc., each of which has an orthogonal dual-polarization antenna having two orthogonal antenna elements. In the present embodiment, as an example, a mobile terminal conforming to 5G NR is assumed to be the radio terminal 2 to be measured, and a case where the radio terminal 2 is subjected to the FR2 conformance test specified by 3GPP will be described as an example.

The positioner 10 holds the wireless terminal 2 to be measured near the reference point O in the measurement space, rotates the held wireless terminal 2 about the reference point O, and determines the position of the wireless terminal 2 (θ, φ ) (also referred to as rotational position (θ, φ)). The reference point O is located at a predetermined distance R from the phase center Q of the measurement antenna 20 in the reference direction of its directivity (usually the maximum gain direction orthogonal to the aperture). A distance R between the measurement antenna 20 and the wireless terminal 2 is set so as to satisfy a known distance condition for far-field measurement. Note that the phase center Q of the antenna is a point that can be virtually regarded as a concentration point of radio waves in the emission and incidence of radio waves.

In this embodiment, as shown in FIG. 1, an XYZ orthogonal coordinate system having a reference point O as an origin is assumed. The phase center Q of the measurement antenna 20 is located on the Z-axis, the Y-axis is vertical, and the X-axis is perpendicular to the Y- and Z-axes. The positioner 10 rotates the held wireless terminal 2 around the reference point O as the mechanical rotation center, for example, around at least the Y axis (θ direction) and around the Z axis (φ direction) of the three orthogonal axes XYZ. structure. When the wireless terminal 2 is rotated by the positioner 10 by a rotation angle θ around the Y axis and a rotation angle φ around the Z axis, the (rotational) position indicating the posture or arrangement of the wireless terminal 2 is represented by a pair of (θ, φ). represent. The positioner 10 can also be a positioner with a three-axis rotation structure including rotation around the X-axis.

Although the specific structure of the positioner 10 will not be described in detail, for example, as shown in FIG. , 13 can be used as long as it rotates around the Y-axis and around the Z-axis at predetermined angular steps. These rotation angles θ and φ are controlled by the positioner control section 34 under the control of the control section 33, for example. The material and shape of the holding table 11, including its holding mechanism, are those that do not easily affect the radiation characteristics of the terminal antenna 3 of the wireless terminal 2. FIG.

FIG. 2 is a diagram showing the arrangement of the measurement antenna 20 and the terminal antenna 3 in the FR2 conformance test specified by 3GPP in the coordinate system of FIG. As shown in FIG. 2, a terminal antenna 3 indicated as "Tx" is arranged at a position P at a distance r from the reference point O on the Z axis, and "Rx" at a position at a distance R from the reference point O on the Z axis. ” is positioned. The reference point O is the mechanical center of rotation and the position P of the terminal antenna 3 is the working electrical center of rotation. The measurement antenna 20 has a vertically polarized wave antenna 20V and a horizontally polarized wave antenna 20H (see FIG. 8). It is the polarization direction V. The measurement antenna 20 is set so that the main lobe is directed along the Z-axis.

As shown in FIGS. 1 and 2, when the wireless terminal 2 held on the holding base 11 is rotated around the Y axis by a rotation angle θ and around the Z axis by a rotation angle φ, the terminal antenna 3 is The position r(θ, φ) is expressed by the following equation, where (x, y, z) is the position of the terminal antenna 3 in the orthogonal coordinate system XYZ.

FIG. 3 is a diagram showing a state in which the terminal antenna 3 indicated as Tx faces the measurement antenna 20 indicated as Rx with a deviation of the rotation angle φ′. In the case of the IFF (Indirect Far Field) system using an offset parabolic reflector, the directivity of the terminal antenna 3 such as a patch antenna array arranged at the Tx point in the quiet zone can be easily and directly observed. On the other hand, since the directivity at the Rx point for TE waves in two directions assumed from the terminal antenna 3 such as a patch antenna array does not change with the rotation of the wireless terminal 2 around the Z axis, Although compatibility is required, 3GPP technical specifications (TS 38.521-4 annex H) consider that there is a point where the beam peak direction can be aligned, and if the isolation between orthogonal polarized waves (between poles) is 12 dB or more It is decided to admit that they are facing each other.

FIG. 4 is a diagram for explaining angular deviation of the terminal antenna 3. FIG. In the present embodiment, the sensitivity to the TE wave of the specific mode and the distribution as energy are taken into consideration together from the viewpoint of the two directions of the vertical polarization direction V and the horizontal polarization direction H which are orthogonal to each other. In FIG. 4, LRx represents the combined lobe of the vertically polarized wave and the vertically polarized wave on the Rx (measurement antenna 20) side, and LTx represents the combined lobe on the paired Tx (terminal antenna 3) side. In power measurement using SS-RSRPB (SS-Reference Signal Received Power per Branch), the Rx end is used as the transmitting side. When the terminal antenna 3 is at an arbitrary Tx placement position (θ', φ') that is nearly directly opposite, and there is an angular deviation φ" from the Rx placement as shown in FIG. 4(a), the signal on the Tx side The relationship between the intensity or power values TxH, TxV and the signal intensity or power values RxH, RxV on the Rx side is expressed by the following equations.

Based on the above formula, the angular deviation φ″ from the Rx arrangement is individually calculated in the vertical polarization direction V and the horizontal polarization direction H as shown in FIGS. For example, the angle deviation φ" estimated using MMSE (Minimum Mean Square Error) or the like is detected by the signal strength or power value of both vertical and horizontal polarizations. may

FIG. 5 is a diagram showing a coupling example on the Rx projection plane equivalent to the Tx circular polarization. Regarding the physical angular deviation θ″, φ″ with respect to the Rx arrangement, if the angular deviation is only φ″ (θ″=0°), there should be no phase difference between the vertical and horizontal polarizations (δ=0°). , the intensity difference or power difference between the vertical and horizontal polarizations gives a linearly polarized wave for each angle φ direction, and can perform an equivalent φ rotation that can be coupled with a unidirectionally polarized wave of any Tx arrangement.

If θ″ ≠ 0° with an angular deviation in the z-axis direction, by coupling with the circularly polarized wave of the Tx arrangement, it becomes equivalent to an elliptically polarized wave with a phase difference between the vertical and horizontal polarizations (δ ≠ 0°). Especially for circularly polarized waves (δ = 90°), at the equivalent θ rotation position, the signal strengths produced by vertical and horizontal polarizations can be equivalent for any angle φ. By controlling δ and measuring the increase/decrease in the signal strength or power value from these two viewpoints, the facing physical angle and the isolation between poles can be estimated.

FIG. 6 is a diagram for explaining the relationship between the phase difference δ between the vertically polarized wave and the horizontally polarized wave and the angle shift φ″. The composite wave to be generated (composite TE in the figure) is variable by controlling the phase or the phase difference δ of each of the vertical polarization excitation RF section 43 and the horizontal polarization excitation RF section 44. The tilt angle of the composite TE is corresponds to the angular deviation φ″. By synthesizing TE waves in two directions with arbitrary amplitudes and angles, rotation that takes several seconds with mechanical rotation can be electrically achieved in milliseconds or less.

FIG. 7 is a diagram for explaining the measurement method of this embodiment. First, the radio terminal 2 to be measured is mechanically rotated around the Z axis and around the Y axis, and the position where the received power value of the terminal antenna 3 measured by the antenna directivity measuring device 30 is maximized is found. Next, conventionally, as shown in the upper diagram of FIG. was the minimum (the power difference was 12 dB or more).

In the present embodiment, it takes time to mechanically rotate the wireless terminal 2 by 90 degrees. Therefore, the measurement antenna 20 of the antenna directivity measurement system 1 is rotated by 90 degrees by electrical phase rotation, thereby shortening the time. can do. In the electrical phase rotation, not only rotation in the XY plane, but also rotation in the Z-axis direction can be applied, which enables fine adjustment of the positional relationship between the wireless terminal 2 and the measurement antenna 20. FIG.

(Antenna directivity measuring device)
FIG. 8 is a diagram showing a schematic configuration of the entire antenna directivity measuring apparatus 30 according to this embodiment. As shown in FIG. 8, the antenna directivity measurement apparatus 30 includes a detection unit 31, a storage unit 32, a control unit 33, a positioner control unit 34, an operation unit 35, a display unit 36, an RF transmission/reception unit 40, a baseband (BB) It comprises a receiver 50 , a baseband (BB) transmitter 60 and an oscillator 70 . Each component will be described below.

The RF transmitting/receiving section 40 generates a polarized wave signal including vertically polarized waves and horizontally polarized waves as a test signal, and transmits the test signal to the wireless terminal 2 via the measurement antenna 20 . Also, the RF transmitting/receiving section 40 receives from the terminal antenna 3 via the measurement antenna 20 a response signal containing information on the power value of the test signal received by the terminal antenna 3 of the wireless terminal 2 . Note that the RF transmitter/receiver 40 of this embodiment corresponds to the transmitter/receiver of the present invention.

The detection section 31 detects the power value of the test signal from the response signal received by the RF transmission/reception section 40 . Specifically, the detection unit 31 detects the power value (also referred to as the RSRPB value or RSRPB report value) indicated by the SS-RSRPB included in the response signal from the wireless terminal 2 for each branch (first direction and second direction). get.

The control unit 33 performs overall control of the entire antenna directivity measurement system 1, and sets test signal parameters based on information on the power value of the test signal received by the terminal antenna 3. (test signal parameter setting unit 331). The test signal parameters include the amplitude A _V of the vertical polarization signal transmitted from the measurement antenna 20, the amplitude A _H of the horizontal polarization signal, the delay phase δ _V of the vertical polarization signal, and the delay phase δ _H of the horizontal polarization signal. mentioned. The phase difference δ between the vertically polarized signal and the horizontally polarized signal is represented by the delay phase difference δ _V −δ _H.

The positioner control unit 34 controls the driving of the rotating devices 12 and 13 of the positioner 10 under the control of the control unit 33 to rotate the wireless terminal 2 around two axes, thereby changing the rotational position (θ, φ) of the wireless terminal 2 to It can be changed. The rotational position (θ, φ) of the wireless terminal 2 indicates the position, attitude, arrangement direction, direction, or orientation of the wireless terminal 2 .

The operation unit 35 is for receiving an operation input by the user, and may be configured by a touch panel provided on the surface of the display screen of the display unit 36, for example. Alternatively, the operation unit 35 may be configured including an input device such as a keyboard or mouse. Further, the operation unit 35 may be configured by an external control device that performs remote control using a remote command or the like. An operation input to the operation unit 35 is detected by the control unit 33 . For example, the user may arbitrarily specify the communication method, test type, various threshold values, initial values of test signal parameters, and the like using the operation unit 35 .

The display unit 36 displays various information input screens, measurement results, etc. For example, report information (power values, (rank) and test candidate positions where isolation equal to or higher than a predetermined threshold is obtained are displayed.

The storage unit 32 associates the power values of the polarization components of branch 1 (first direction) and branch 2 (second direction) of the test signal received by the terminal antenna 3 with the rotational position (θ, φ) of the wireless terminal 2. is memorized. In addition, the storage unit 32 stores information on the isolation between orthogonal polarizations, information on the amplitudes and phase differences of the vertical and horizontal polarization signals transmitted from the measurement antenna 20, rank information reported from the terminal antenna 3, and the like. is stored in association with the rotational position (θ, φ) of the wireless terminal 2 .

The oscillation section 70 includes a reference signal generation section 71 that generates a common reference signal for synchronizing the vertically polarized wave signal and the horizontally polarized wave signal that constitute the test signal.

The baseband (BB) receiver 50 refers to the reference signal generated by the reference signal generator 71, demodulates the uplink (UL) signal received by the RF transmitter/receiver 40 via the measurement antenna 20, and demodulates the baseband signal. It has an uplink (UL) demodulator 51 for acquiring the signal.

The baseband (BB) transmission unit 60 refers to the reference signal generated by the reference signal generation unit 71, and causes the RF transmission/reception unit 40 to generate a downlink (DL) signal to be transmitted via the measurement antenna 20. , includes a downlink (DL) modulation unit 61 that generates a baseband modulated signal.

(RF transceiver)
The RF transmitter/receiver 40 includes a first phase shifter 41 , a second phase shifter 42 , a vertical polarization excitation RF section 43 , a horizontal polarization excitation RF section 44 and an anchor excitation RF section 45 .

The first phase shifter 41 phase-shifts the vertical polarization signal based on the phase shift amount _δV given by the test signal parameter setting section 331 of the control section 33, and the second phase shifter 42 shifts the phase of the test signal Based on the phase shift amount _δH given by the parameter setting section 331, the horizontal polarization signal is phase-shifted. The vertically polarized wave signal and the horizontally polarized wave signal subjected to phase shift operation by the first and second phase shifters 41 and 42 have a phase difference δ (=δ _V −δ _H ).

The vertical polarization excitation RF unit 43 up-converts the baseband DL modulated signal generated by the DL modulation unit 61 based on information on the amplitude _Av given from the test signal parameter setting unit 331 of the control unit 33. At the same time, the phase is controlled by the first phase shifter 41 to generate a vertically polarized wave signal to excite the vertically polarized wave antenna 20V.

The horizontal polarization excitation RF unit 44 up-converts the baseband DL modulated signal generated by the DL modulation unit 61 based on the amplitude _AH information provided from the test signal parameter setting unit 331 of the control unit 33. At the same time, the phase is controlled by the second phase shifter 42 to generate a horizontally polarized wave signal to excite the horizontally polarized wave antenna 20H.

The anchor excitation RF section 45 is adapted to excite the link antenna 80 . The link antenna 80 is an antenna for establishing or maintaining a link (call) with the wireless terminal 2. For example, a link antenna for LTE used in non-standalone mode, It is a link antenna for 5G used in standalone mode.

(control part)
FIG. 9 is a block diagram showing an outline of the functions of the control section 33. As shown in FIG. As shown in FIG. 9, the control unit 33 includes a test signal parameter setting unit 331, a local maximum determination unit 332, an electrical phase rotation control unit 333, a mechanical rotation control unit 334, an isolation determination unit 335, and a directivity determination unit. 336 is provided.

The test signal parameter setting unit 331 sets parameters (test signal parameters) that define the test signal. Amplitudes A _V , A _H , respective phase shifts δ _V , δ _H , and phase difference δ.

The maximum determination unit 332 determines whether or not there is a maximum power value at any position of the wireless terminal 2 stored in the storage unit 32 . If there is a maximum, information on the amplitudes A _V and A _H of the test signal transmitted at that time, information on the phase difference δ, information on the position (θ, φ) of the wireless terminal 2, and the power value received by the terminal antenna 3 Get information about

The electrical phase rotation control section 333 controls the amplitudes A _V , _AH and the phase difference .delta. In addition, when the isolation determination unit 335 determines that the difference in power value is smaller than the predetermined threshold, the electrical phase rotation control unit 333 controls the vertical polarization signal and the horizontal polarization signal constituting the test signal to be transmitted. at least one of the respective amplitudes A _V , A _H and the phase difference δ of are further varied.

Specifically, the electrical phase rotation control section 333 controls the amplitudes A _V and A _H of the vertically polarized wave signal and the horizontally polarized wave signal that constitute the test signal, and the phase difference δ. is performed. For example, when the phase difference .delta. By measuring the difference in the power value of the test signal before and after rotating by 90°, the isolation between orthogonal polarizations can be confirmed. Further, for example, when the phase difference δ is not 0, the test signal is elliptically polarized, and when the phase difference δ is 90°, the test signal is circularly polarized. For example, by changing the phase difference δ in the vicinity of 90° and performing electrical phase rotation, it is possible to obtain information about the rotation (inclination) of the terminal antenna 3 in the direction of propagation of radio waves (Z-axis direction). Therefore, when the maximum determination unit 332 determines that there is no maximum in the power value, the electrical phase rotation control unit 333 adjusts the vertical polarization signal and the horizontal polarization signal so that the possibility of the existence of the maximum becomes high. , each amplitude A _V , A _H and the phase difference δ are changed.

The mechanical rotation control unit 334 controls the positioner control unit 34 so as to change the rotational position (orientation) of the wireless terminal 2. For example, the maximum power value determination unit 332 determines that there is no maximum power value. In such a case, the positioner 10 changes the rotational position (θ, φ) of the wireless terminal 2 so that the possibility of the existence of the local maximum increases. Further, when the isolation determination unit 335 determines that the difference in power value is smaller than 12 dB, the mechanical rotation control unit 334 causes the positioner 10 to rotate the wireless terminal 2 so that the difference in power value increases. (θ, φ) are further changed.

The rotation operation of the wireless terminal 2 by the mechanical rotation control unit 334 and the electrical phase rotation operation by the electrical phase rotation control unit 333 may be used together, or either one may be performed independently.

The isolation judging section 335 generates a linearly polarized wave signal obtained by rotating the plane of polarization of the test signal by 90° around the Z-axis, which is the traveling direction of radio waves, as the test signal and transmits it from the measurement antenna 20. Whether the difference between the power value of the linearly polarized wave signal received by the terminal antenna 3 and the power value detected when using the original test signal before rotating the plane of polarization by 90° is 12 dB or more. is determined. For example, when there is a maximum power value, the isolation determination unit 335 sets the plane of polarization of the test signal used when obtaining the maximum power value at the maximum to 90° around the Z-axis, which is the radio wave traveling direction. A linearly polarized wave signal obtained by rotation is generated as a test signal and transmitted from the measurement antenna, and the power value and the maximum power value of the linearly polarized wave signal received by the terminal antenna 3 detected by the detection unit 31. is 12 dB or more.

The directivity determination unit 336 determines that there is a maximum value of the power of the test signal received by the terminal antenna 3 by the maximum determination unit 332, and the measurement is performed by the isolation determination unit 335 around 90° rotation of the plane of polarization. When it is determined that the difference in the power value of the test signal is greater than a predetermined threshold value, for example, 12 dB, it is determined that the measurement antenna 20 and the terminal antenna 3 face each other including the matching of the plane of polarization, and The position (θ, φ) of the wireless terminal 2 at that time is stored in the storage unit 32 and displayed on the display unit 36 as a conformance test candidate position.

A part or all of the antenna directivity measurement device 30 is configured by, for example, a computer device. This computer device includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an external interface (I/F) section, an SSD (Solid State Drive) and a hard disk device. and various input/output ports.

The CPU performs overall control of the antenna directivity measurement system 1 as a target. The ROM stores an OS (Operating System) for booting up the CPU, other programs, parameters for control, and the like. The RAM stores the OS and application execution codes and data used by the CPU for operation. The external interface (I/F) section has an input interface function for inputting a predetermined signal and an output interface function for outputting a predetermined signal.

The external I/F section is connected to the positioner 10 via a network. An operation unit 35 and a display unit 36 are connected to the input/output port. The operation unit 35 is a functional unit for inputting various information such as commands, and the display unit 36 is a functional unit for displaying various information such as an input screen for the various information and measurement results.

The computer device described above functions as the detection unit 31 and the control unit 33 by the CPU executing a program stored in the ROM using the RAM as a work area. A test signal parameter setting unit 331, a maximum determination unit 332, an electrical phase rotation control unit 333, a mechanical rotation control unit 334, an isolation determination unit 335, and a directivity determination unit 336 included in the control unit 33 are also implemented by the CPU of the RAM. It is realized by executing a predetermined program stored in the ROM in the work area.

(Antenna directivity measurement method)
Next, a method for measuring the directional characteristics of the terminal antenna 3 provided in the radio terminal 2 will be described.

10 to 13 are flow charts showing an outline of the antenna directivity measurement method according to this embodiment. In the following, the case where the FR2 conformance test (see TS 38.521-4, TR 38.810) defined by 3GPP is performed will be described as an example, but the terminal antenna 3 provided in the wireless terminal 2 is not limited to this. can be used as a method to quickly measure the accurate directional characteristics of , based on the information of the orthogonal interpolarization isolation.

First, as shown in FIGS. 1 and 10, the wireless terminal 2 is installed on the positioner 10 rotatable about two axes (step S1). The positioner 10 can arbitrarily change the position or rotational position (θ, φ) of the wireless terminal 2 .

Then, according to the 3GPP technical specification (TS 38.521-4 annex H.1, "Procedure for finding UE direction"), the position (θ, φ) of the wireless terminal 2 that satisfies the conditions described in the technical use (the same annex H.0). (step S2).

In step S2, step S2-1 using Rx beam direction search described in 3GPP technical specifications (TS 38.521-4 annex H.1.1) or RSRPB based described in 3GPP technical specifications (TS 38.521-4 annex H.1.2) Either step S2-2 using scan or step S2-3 using the processing method according to the present embodiment can be adopted. A case of using the processing method (step S2-3) according to the present embodiment will be described below.

As shown in FIG. 11, in step S2-3, first, a call connection is made with the terminal antenna 3 using the link antenna 80, and the antenna directivity measuring device 30 receives the reported values such as RSRPB from the wireless terminal 2. It is made possible to continue to obtain (step S11).

Next, the antenna directivity measurement device 30 uses a test signal with an angle near the phase difference of 90° centering on the elliptical polarization (phase difference δ≈90°) formed by the vertical and horizontal polarizations of the test signal. to acquire the reported value from the wireless terminal 2 (step S12).

Specifically, the antenna directivity measuring apparatus 30 transmits the vertically polarized wave signal and the horizontally polarized wave signal that constitute the test signal from the vertically polarized wave antenna 20V and the horizontally polarized wave antenna 20H of the measurement antenna 20, respectively, and the detection unit 31, a reported value of the reception state at the terminal antenna 3 is acquired (power measurement processing) (step S13). The reported values include the power value (P1) of the polarization component in the first direction of the test signal received by the terminal antenna 3, the power value (P2) of the polarization component in the second direction orthogonal to the first direction, and rank information. etc. The reported values detected by the detection unit 31 are stored in the storage unit 32 in association with the position (θ, φ) of the wireless terminal 2 and the parameters (A _V , A _H , δ _V , δ _H ) of the vertical and horizontal polarization signals. Keep The power measurement process will be explained later.

Based on the information of the reported value stored in the storage unit 32, the local maximum determination unit 332 of the control unit 33 receives the terminal antenna 3 in the range of the position (θ, φ) scanned by mechanical rotation and electrical phase rotation. It is determined whether or not there is a sufficient maximum in the power value of the test signal obtained (step S14). When the local maximum determination unit 332 of the control unit 33 determines that there are sufficient local maxima, the position (θ, φ) at the local maximum point, the parameters of the vertical and horizontal polarization signals (A _V , _AH , δ _V , δ _H ) and the power values (received power values P1, P2) of the test signal received by the terminal antenna 3 are acquired, and the process proceeds to step S15.

When the mechanical rotation control unit 334 of the control unit 33 determines that the power value of the test signal received by the terminal antenna 3 does not have a sufficient maximum (No in step S14), scanning can be performed by electrical phase rotation. The rotational position (θ, φ) is moved and scanned so that the facing surface of the terminal antenna 3 of the wireless terminal 2 becomes a different surface by mechanical rotation so as to ensure a margin of the received power value of about 100 (step S20). Specifically, the mechanical rotation control unit 334 of the control unit 33 controls the positioner control unit 34 to rotate the wireless terminal 2 held on the holding table 11 of the positioner 10 so as to define the rotational position (θ, φ). One or both of the angles θ and φ are changed sequentially. The method of changing the rotation angles θ and φ is, for example, based on already obtained data so that the existence of the maximum can be confirmed earlier, or the possibility of the existence of the maximum can be increased. After changing the set values of the rotation angles θ and φ in step S20, the process returns to step S12.

In step S20, the electrical phase rotation control unit 333 controls to change the parameters (amplitudes A _V , A _H , phase difference δ) of the vertical and horizontal polarization signals constituting the test signal together with the mechanical rotation or independently. However, electrical phase rotation may be performed.

On the other hand, in step S15, the control unit 33 determines whether Rank 2 has been acquired based on the reported value from the wireless terminal 2 (step S15). Here, “Rank2” indicates that the rank of the electromagnetic tensor is two. This means that when the wireless terminal 2 receives signals of the same frequency through a plurality of antennas, they can be separated into two unique waves. The rank information can be obtained by reporting the value of RI (Rank Indicator) from the wireless terminal 2 separately from the RSRPB report.

If it is determined in step S15 that Rank 2 has not been obtained (NO in step S15), the direction of the rotational scanning plane (plane perpendicular to the Z-axis) is approximately determined, and the Rank 2 state is secured by RSRPB. Electrical phase rotation is performed within the margin of the received power value, and the rotational position (.theta., .phi.) is moved and scanned (step S21). After changing the set values of the rotation angles θ and φ in step S21, the process returns to step S12.

If it is determined in step S15 that Rank 2 has been acquired (yes in step S15), the isolation determination unit 335 of the control unit 33 selects the same phase (phase difference δ=0°) vertical Rotate the plane of polarization by 90° in the direction of rotation φ by changing the amplitude difference between the polarized wave and the horizontal polarized wave, obtain the received power value from RSRPB, and obtain the received power of the linearly polarized signal before and after rotating the plane of polarization by 90°. is calculated as an index of the orthogonal polarization isolation of the terminal antenna 3 (step S16). Specifically, the isolation determination unit 335 of the control unit 33 determines the linearly polarized signal based on the rotational position (θ, φ) corresponding to the maximum point and the parameters (A _V , _AH ) of the vertical and horizontal polarization signals. Determine the amplitudes (A _V , A _H ) of the vertically and horizontally polarized signals when the plane of polarization of the wave is rotated 90° in the direction of rotation φ, generate the vertically and horizontally polarized signals by the RF transmitter/receiver 40, and measure Antenna 20 is excited to transmit vertically and horizontally polarized signals (linear polarization) as test signals. Then, the detection unit 31 acquires the received power value indicated by the RSRPB from the terminal antenna 3 (also referred to as the RSRPB value or the RSRPB report value), calculates the received power difference, and stores it in the storage unit 32 (power measurement process) ( step S17)

Next, based on the RSRPB value information stored in the storage unit 32, the directivity determination unit 336 of the control unit 33 determines the RSRPB value acquired corresponding to the maximum point and the electrical phase rotation to 90 degrees in the φ direction. It is determined whether or not the difference from the RSRPB value when rotated by degrees is 12 dB or more (step S18). If it is determined that the RSRPB value is 12 dB or more, the result display process of step S19 is performed and the process is terminated.

On the other hand, if it is determined that the RSRPB value is less than 12 dB (No in step S18), the facing surface of the terminal antenna 3 of the wireless terminal 2 is mechanically rotated to ensure isolation ready for the 3GPP test. are moved and scanned by the rotation angles .theta. and .phi. After changing the set values of the rotation angles θ and φ in step S20, the process returns to step S12.

As described above, in the loop of steps S12→S13→S14→S15→S21→S12 in FIG. 11, in steps S12→S13→S14→S15, the phase difference δ is swung around 90° to determine whether the maximum RSRPB value and Rank 2 have been acquired from the wireless terminal 2 .

In the case of rotational scanning in the θ direction by electrical phase rotation, the phase difference δ is used to switch between circularly polarized waves, elliptical polarized waves, and linearly polarized waves (similar to how the cut edge of a chipped apple changes depending on the viewing direction), In the case of rotational scanning in the φ direction (because if θ does not match, the rotation in the φ direction contributes obliquely with a covariant component and the RSRPB reported value is displaced in the minimum direction), while the phase difference δ is fixed, The angle is changed by changing the combined amplitude _AV and amplitude _AH . In step S12, the phase difference δ is set in step S13 in order to perform RSPRB measurement in response to the specification of the rotation range for the alignment of the two axes (θ, φ) in step S21. A polarized wave is generated and transmitted, and a report value is obtained from the wireless terminal 2 .

(power measurement processing)
Here, the power measurement process will be described with reference to FIG. 12 .

A test signal parameter setting unit 331 of the control unit 33 sets parameters (A _V , A _H , δ _V , δ _H ) of the vertical and horizontal polarization signals based on the RSRPB report values detected by the detection unit 31. . Based on the parameters set by the test signal parameter setting unit 331 of the control unit 33, the RF transmission/reception unit 40 performs vertical polarization excitation with the phase shift amount _δV and the phase shift amount _δH that provide the designated phase difference δ. The RF section 43 generates a vertically polarized wave signal, and the horizontally polarized excitation RF section 44 generates a horizontally polarized wave signal (step S31).

Next, a vertically polarized wave signal is output from the vertically polarized wave antenna 20V, and a horizontally polarized wave signal is output from the horizontally polarized wave antenna 20H (step S32).

The wireless terminal 2 calculates the power value of the polarization component in the first direction (RSRPB1 component) and the power value of the polarization component in the second direction (RSRPB2 component) of the test signal composed of the vertically and horizontally polarized signals received by the terminal antenna 3. A value is acquired (step S33).

The wireless terminal 2 transmits a response signal including the power value of the polarization component in the first direction (RSRPB1 report value) and the power value of the polarization component in the second direction (RSRPB2 report value) (step S34).

Next, the RF transmitter/receiver 40 of the antenna directivity measurement device 30 receives the response signal via the measurement antenna 20 (step S35). The received response signal is down-converted and sent to the uplink demodulator 51 for demodulation. During EN-DC (E-UTRA-NR Dual Connectivity) connection, a response signal is received via the link antenna 80 .

The detection unit 31 detects the RSRPB1 and RSRPB2 report values around the rotation direction (φ direction) around the Z-axis at the rotational position (θ, φ) determined by mechanical rotation and electrical phase rotation, and the RSRPB for maximum discrimination. The differences are individually acquired, stored in the storage unit 32, and data is passed from the storage unit 32 to the control unit 33 (step S36).

(Result display processing)
FIG. 13 shows the result display process. As shown in FIG. 13 , in the result display process, a list of RSRPB information corresponding to rotational positions (θ, φ) as position information stored in the storage unit 32 and 3GPP test candidate positions that provide an isolation of 12 dB or more are displayed. is displayed on the display unit 36 (step S40).

(action/effect)
As described above, in the antenna directivity measurement system 1 according to the present embodiment, the isolation judging section 335 rotates the plane of polarization of the test signal by 90° around the Z-axis, which is the traveling direction of radio waves. A signal is generated as a test signal and transmitted from the measurement antenna 20, and the power value of the linearly polarized wave signal received by the terminal antenna 3, which is detected by the detection unit 31, and the original test signal before the plane of polarization is rotated by 90° is used, it is determined whether or not the difference from the power value detected by the detection unit 31 is equal to or greater than a predetermined threshold. With this configuration, the plane of polarization of the test signal to be transmitted is rotated by 90° without actually mechanically rotating the wireless terminal 2 by 90°, and the difference between the power values before and after the rotation of the test signal received by the terminal antenna 3 is calculated. It is possible to confirm the isolation between orthogonal polarizations at the terminal antenna 3 based on . As a result, it is not necessary to actually rotate the wireless terminal 2 to check the isolation, so the time required to measure the directivity characteristics of the wireless terminal 2 can be greatly reduced.

Further, in the antenna directivity measurement system 1 according to the present embodiment, the control unit 33 determines whether or not there is a maximum power value at any position of the wireless terminal 2 stored in the storage unit 32. The determination unit 332 is further provided, and the isolation determination unit 335, when there is a maximum power value, converts the plane of polarization of the test signal used when obtaining the maximum power value at the maximum value to Z, which is the radio wave traveling direction. A linearly polarized wave signal obtained by rotating 90° around the axis is generated as a test signal and transmitted from the measurement antenna 20, and the power value of the linearly polarized wave signal received by the terminal antenna 3 detected by the detection unit 31 and , the difference from the maximum power value is 12 dB or more. With this configuration, it is possible to specify the position (θ, φ) of the wireless terminal 2 at which the required isolation between orthogonal polarizations can be secured in the terminal antenna 3 . That is, it is possible to obtain accurate information on the position of the wireless terminal 2 in which the measurement antenna 20 and the terminal antenna 3 face each other.

In addition, in the antenna directivity measurement system 1 according to the present embodiment, the control unit 33 is controlled when the local maximum determination unit 332 determines that there is no maximum power value, or when the isolation determination unit determines that the power value difference is a predetermined value. at least one of the amplitude (A _V , A _H ) and the phase difference (δ) of each of the vertically polarized wave signal and the horizontally polarized wave signal that constitute the test signal to be transmitted when it is determined to be smaller than the threshold value of An electrical phase rotation controller 333 is provided to change the phase. For this purpose, the RF transmitter/receiver 40 includes a first phase shifter 41 that shifts the phase of the vertically polarized signal based on the phase difference δ, and a second phase shifter 42 that shifts the phase of the horizontally polarized signal. there is With this configuration, not only when the terminal antenna 3 rotates around the Z-axis, which is the radio wave propagation direction, but also when the terminal antenna 3 rotates around, for example, the Y-axis orthogonal to the Z-axis, The existence of power maxima can be accurately determined, or the orthogonal cross-polarization isolation of the terminal antennas can be accurately determined, thereby allowing the orientation of the terminal antennas 3 to be determined more accurately. .

In addition, in the antenna directivity measurement system 1 according to the present embodiment, the control unit 33 controls the control unit 33 when the maximum power value determination unit 332 determines that there is no maximum power value, or when the isolation determination unit 335 determines that there is no power value difference. It further includes a mechanical rotation control unit 334 that changes the position (θ, φ) of the wireless terminal 2 by the positioner 10 when it is determined that the position is smaller than a predetermined threshold. With this configuration, it is possible to accurately determine the existence of a local maximum in the received power value of the terminal antenna 3, and to accurately determine the isolation between orthogonal polarizations of the terminal antenna 3. It is possible to search for conformance test candidate positions in which the measurement antenna 20 and the terminal antenna 3 face each other beyond the possible range.

INDUSTRIAL APPLICABILITY As described above, the present invention has the effect of being able to quickly measure the directivity characteristics of an antenna of a wireless terminal capable of ensuring the required orthogonal polarization isolation. and useful throughout the measurement method.

1 antenna directivity measurement system 2 wireless terminal 3 terminal antenna 10 positioner (terminal rotation mechanism)
REFERENCE SIGNS LIST 11 pedestal 12, 13 rotating device 20 measurement antenna 20H horizontal polarization antenna 20V vertical polarization antenna 30 antenna directivity measurement device 31 detection unit 32 storage unit 33 control unit 34 positioner control unit 35 operation unit 36 display unit 40 RF transmission/reception unit 41 first phase shifter 42 second phase shifter 43 vertical polarization excitation RF unit (V polarization excitation RF unit)
44 horizontal polarization excitation RF unit (H polarization excitation RF unit)
45 anchor excitation RF unit 50 baseband reception unit (BB reception unit)
51 Uplink demodulator (UL demodulator)
60 baseband transmitter (BB transmitter)
61 downlink modulation unit (DL modulation unit)
70 oscillation unit 71 reference signal generator 80 link antenna 331 test signal parameter setting unit 332 maximum determination unit 333 electrical phase rotation control unit 334 mechanical rotation control unit 335 isolation determination unit 336 directivity determination unit

Claims (3)

An antenna directivity measurement system (1) for measuring the directivity of a terminal antenna provided in a wireless terminal,
a measurement antenna (20) for transmitting and receiving radio waves to and from the terminal antenna;
A polarized wave signal including a vertically polarized wave signal and a horizontally polarized wave signal is transmitted to the wireless terminal as a test signal via the measurement antenna, and the wireless terminal receives information on the power value of the test signal received by the terminal antenna. a transmitting/receiving unit (40) for receiving the response signal including the terminal antenna via the measurement antenna;
a detection unit (31) for detecting the power value of the test signal from the response signal received by the transmission/reception unit;
A straight line obtained by changing the amplitude ratio and phase difference between the vertical polarization signal and the horizontal polarization signal and rotating the plane of polarization of the test signal by 90° around the axis (Z), which is the direction of radio wave propagation. an electrical phase rotation control unit (333) that causes the transmitting/receiving unit to generate a polarized wave signal;
The generated linearly polarized signal is transmitted from the measurement antenna as a test signal, and the power value of the linearly polarized signal received by the terminal antenna detected by the detection unit and the power value before rotating the plane of polarization by 90° an isolation determination unit (335) that determines whether or not the difference from the power value detected when using the original test signal is equal to or greater than a predetermined threshold;
a terminal rotation mechanism (10) that holds and rotates the wireless terminal and changes the position of the wireless terminal;
a storage unit (32) that stores the detected power value in association with the position of the wireless terminal;
a maximum determination unit (332) that determines whether or not there is a maximum power value at any position of the wireless terminal stored in the storage unit;
In the isolation determination section, if there is a maximum power value, the electrical phase rotation control section changes the amplitude ratio and phase difference between the vertical polarization signal and the horizontal polarization signal to determine the maximum power value. causing the transmitting/receiving unit to generate a linearly polarized wave signal obtained by rotating the plane of polarization of the test signal used when obtaining the maximum power value at 90° about the direction of radio wave propagation, The generated linearly polarized signal is transmitted as a test signal from the measurement antenna, and the difference between the power value of the linearly polarized signal received by the terminal antenna detected by the detection unit and the maximum power value is the Determine whether or not there is a predetermined threshold or more ,
The transmission/reception unit includes a first phase shifter (41) for phase-shifting the vertical polarization and a second phase shifter (42) for phase-shifting the horizontal polarization, and the electrical phase rotation control unit is the amplitude (AV, AH) and the phase difference ( An antenna directivity measurement system, wherein at least one of δ) is varied. When the isolation determination unit determines that the difference in power value is smaller than the predetermined threshold, the electrical phase rotation control unit controls the vertical polarization signal and the horizontal polarization signal constituting the test signal to be transmitted. 2. Antenna directivity measurement system according to claim 1 , wherein at least one of each amplitude (AV, AH) and phase difference ([delta]) is further varied. An antenna directivity measurement system (1) for measuring the directivity of a terminal antenna provided in a wireless terminal,
a measurement antenna (20) for transmitting and receiving radio waves to and from the terminal antenna;
A polarized wave signal including a vertically polarized wave signal and a horizontally polarized wave signal is transmitted to the wireless terminal as a test signal via the measurement antenna, and the wireless terminal receives information on the power value of the test signal received by the terminal antenna. a transmitting/receiving unit (40) that receives the response signal including the terminal antenna via the measurement antenna;
a detection unit (31) for detecting the power value of the test signal from the response signal received by the transmission/reception unit;
A straight line obtained by changing the amplitude ratio and phase difference between the vertical polarization signal and the horizontal polarization signal and rotating the plane of polarization of the test signal by 90° around the axis (Z), which is the direction of radio wave propagation. an electrical phase rotation control unit (333) that causes the transmitting/receiving unit to generate a polarized wave signal;
The generated linearly polarized signal is transmitted from the measurement antenna as a test signal, and the power value of the linearly polarized signal received by the terminal antenna detected by the detection unit and the power value before rotating the plane of polarization by 90° an isolation determination unit (335) that determines whether or not the difference from the power value detected when using the original test signal is equal to or greater than a predetermined threshold;
a terminal rotation mechanism (10) that holds and rotates the wireless terminal and changes the position of the wireless terminal;
a storage unit (32) that stores the detected power value in association with the location of the wireless terminal;
a maximum determination unit (332) that determines whether or not there is a maximum power value at any position of the wireless terminal stored in the storage unit;
In the isolation determination section, if there is a maximum power value, the electrical phase rotation control section changes the amplitude ratio and the phase difference between the vertical polarization signal and the horizontal polarization signal to determine the maximum power value. causing the transmitting/receiving unit to generate a linearly polarized wave signal obtained by rotating the plane of polarization of the test signal used when obtaining the maximum power value at 90° about the direction of radio wave propagation, The generated linearly polarized signal is transmitted as a test signal from the measurement antenna, and the difference between the power value of the linearly polarized signal received by the terminal antenna detected by the detection unit and the maximum power value is the Determine whether or not there is a predetermined threshold or more,
It is determined by the maximum determination unit that there is a maximum value of the power of the test signal received by the terminal antenna, and the difference in the power values of the test signal detected before and after the 90° rotation of the plane of polarization by the isolation determination unit. is greater than or equal to the predetermined threshold, the antenna directivity measuring system further comprising a display unit (36) for displaying the location of the wireless terminal as a candidate location for testing.

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