JP3096993B2 - Radio wave environment measurement device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio wave environment measuring device for measuring characteristics of a radio wave propagation path in a mobile radio system or the like. 2. Description of the Related Art In various mobile wireless systems such as a mobile phone and a mobile phone, it is necessary to grasp the propagation state of radio waves. For example, by investigating the relationship between the installation position of the wireless base station and the propagation condition of radio waves in the service area (zone), the wireless base station can be installed at the optimum position. Therefore, it is demanded that such a radio wave propagation state can be easily measured.

[0002]

2. Description of the Related Art Conventionally, in order to measure the propagation state of a radio wave, a radio wave is radiated from a fixed radio device corresponding to a radio base station via a non-directional antenna, and the radio wave is received by a mobile radio device. Thus, the distance from the fixed wireless device and the reception level are measured. In an urban area, various high-rise buildings serve as radio wave reflectors, so mobile radios can distinguish whether they have received a direct wave from a fixed radio or a reflected wave from a reflector. Is difficult and
Therefore, it is difficult to measure the distance from the fixed wireless device in the mobile wireless device.

[0003] Therefore, a fixed wireless device modulates a carrier wave using a pseudo-noise (PN) code having a large autocorrelation and transmits the modulated signal. Identify whether it is a wave or not and further set the modulation speed to
There is also proposed a configuration in which the reflection point can be resolved by increasing the frequency to about 0 MHz.

[0004]

Problems to be Solved by the Invention In the conventional example,
A mobile radio receives radio waves from a fixed radio and measures its reception level and distance. The disadvantage is that multipath interference from reflective objects makes it difficult to measure. In order to improve the distance resolution, it is necessary to shorten the range cell, which is the minimum resolution distance, which means increasing the modulation speed. The band becomes wider. Since there is a predetermined restriction on the band used for radio waves, it is not possible to adopt means for increasing the required band for radio waves.
That is, it has been difficult to improve the distance resolution.

[0005] Further, since a mobile radio usually receives radio waves from a fixed radio using an omnidirectional antenna, it is impossible to measure the direction. In addition, when azimuth measurement is performed using a directional antenna, there is a great possibility that the direction of the side lobe is mistaken for the direction of the main lobe (main beam), and therefore, azimuth measurement has been difficult. SUMMARY OF THE INVENTION It is an object of the present invention to improve distance resolution and accurately perform azimuth measurement.

[0006]

The radio wave environment measuring apparatus according to the present invention will be described with reference to FIG. 1. First and second radios 1 and 2 are provided. The first wireless device 1 has a transmitting / receiving unit 4 for transmitting / receiving a signal and a signal transmitted / received from the transmitting / receiving unit 4. Signal and the second
And a measuring unit 5 for measuring a propagation distance and a reception level of a radio wave based on the signal returned from the wireless device 2.

The transmission / reception unit 4 of the first wireless device 1 has a relay unit for receiving the signal returned by the second wireless device 2 and transmitting the signal again. A reception signal after performing transmission and reception a preset number of times,
It has means for measuring a propagation distance of a radio wave, a reception level, and the like based on a signal transmitted first.

Further, the antenna of the first wireless device 1 is constituted by an omnidirectional antenna and a directional antenna.
Has side lobe suppression means for determining a received signal by a main lobe when a reception level by a directional antenna is higher than a reception level by an omni-directional antenna.

The transmitting / receiving section 4 of the first radio 1 has means for sweeping the transmission signal frequency, and the measuring section 5
And a means for measuring a propagation distance of a radio wave, a reception level, and the like based on a change in a phase difference between a signal folded back from the wireless device 2 and a transmission signal.

The transmitting / receiving section 4 of the first radio 1 has means for transmitting a signal modulated with a code having a large autocorrelation, and the measuring section 5 converts the signal returned from the second radio 2 into a signal. It has means for measuring the propagation distance of radio waves, the reception level, and the like by performing autocorrelation processing on the code obtained by demodulation.

The transmission / reception unit 3 of the second wireless device 2 has a delay circuit whose delay time of relay transmission is controlled by a command from the first wireless device 1.

The measuring section 5 of the first radio 1 calculates a phase difference between the signal folded back from the second radio 2 and a reference carrier having a phase difference of 90 degrees, and squares the phase difference output signal. It has means for synthesizing.

[0013]

The first radio 1 is set as a fixed side, the transmission / reception unit 4 of the first radio 1 transmits a signal, and the second radio 2 is moved to an arbitrary position. The transmission / reception unit 3 of the wireless device 2 receives and transmits the return signal, and this is received by the transmission / reception unit 4 of the first wireless device 1. Therefore, the measuring unit 5 measures the propagation distance of the radio wave. Therefore, a distance twice as long as the propagation distance of the radio wave between the first wireless device 1 and the second wireless device 2 is measured, so that the distance resolution can be improved. The reception level can be easily corrected because the gain of the transmission / reception unit 3 of the second wireless device 2 is known in advance.

The transmitting / receiving section 4 of the first wireless device 1 also has the second
By providing folding means similar to the transmission / reception unit 2 of the wireless device 2 and making a round trip between the first and second wireless devices 1 and 2 a plurality of times, the propagation distance of the radio wave is reduced by the first and second wireless devices. Since the distance between the two wireless devices 1 and 2 is equal to (2 × the number of times of folding), when the effect of the reflected wave is large when the actual distance between the first wireless device 1 and the second wireless device 2 is short, Also in this case, the apparent propagation distance between the direct wave and the reflected wave can be increased, so that the distance resolution can be improved.

The omnidirectional antenna of the first radio 1 has
The directional antenna has the same gain in the horizontal direction of 360 degrees, and the directional antenna has a larger gain in the direction of the main lobe (main beam) than the gain of the omni-directional antenna, and has a higher gain in the direction of the side lobe. Therefore, by comparing the reception levels of the omnidirectional antenna and the directional antenna, it is possible to perform reception by suppressing the side lobe. Main lobe (main beam)
Can be measured accurately.

The means for switching or sweeping the transmission signal frequency of the transmission / reception unit 4 of the first wireless device 1 provides the measurement unit 5
In this case, the phase difference between the transmission signal and the reception signal changes by changing the frequency, so that the propagation distance can be obtained based on the wave number ratio within the propagation distance of the radio wave.

Also, a signal modulated by a code such as an M-sequence or a Barker code having a large autocorrelation is transmitted from the transmitting / receiving section 4 of the first wireless device 1, and a signal folded back by the second wireless device 2 is received and demodulated. By autocorrelation processing of the code obtained by
Since the direct wave can be easily identified, the distance resolution can be improved.

Further, a delay circuit is provided in the transmitting / receiving section 3 of the second wireless device 2, and the delay time can be controlled to zero or an arbitrary value by decoding a command using a code from the first wireless device 1. The propagation distance of the radio wave between the first and second wireless devices 1 and 2 can be intentionally extended. Therefore, even in the case of a short distance, the propagation distance is apparently increased, so that the influence of the reflected wave that does not pass through the second wireless device 2 can be eliminated, and the distance resolution can be improved.

In the measuring section 5 of the first wireless device 1, the phase difference between the signal folded back from the second wireless device 2 and the reference carrier having a phase difference of 90 degrees is determined by a phase comparator or the like. By calculating and squaring the phase difference output signals, it is possible to avoid the problem caused by the phased blind in which the phase comparison output signal disappears.

[0020]

FIG. 2 is a block diagram of a transmission / reception unit of a fixed wireless device according to an embodiment of the present invention.
Is a directional antenna, 13, 14, 22, and 26 are directional couplers, 15, 28, and 35 are changeover switches, 16 is a reception wave detection circuit, 17 is a side lobe suppression processing circuit, 18 is a transmission / reception unit, and measurement described later. Control circuit for controlling the section, 19 is a circulator, 20, 29, 31, and 36 are filters,
1, 32 are amplifiers, 23 is a phase shifter, 24, 30, 38 are mixers, 25 is a variable frequency oscillator, 27 is a modulator,
Reference numeral 3 denotes a modulation control unit that controls the modulator 27 according to the CW mode, radar mode, and hopping mode; 34, a code generation unit that generates a Barker code, a PN code, and the like;
Is a terminal for receiving intensity measurement for connecting a spectrum analyzer or the like, and 40 is a measuring unit.

This embodiment shows a case where the fixed wireless device is the first wireless device 1 of FIG. 1 and the mobile wireless device is the second wireless device 2 of FIG. 1. Sometimes, it can be moved to any position simply by being fixed.
The changeover switch 15 in the transmission / reception section of the fixed wireless device,
28 and 35 are controlled by a control circuit 18, and the changeover switch 15 is connected to the circulator 19 and the directional coupler 13,
14 is connected, and it is also possible to arbitrarily select the non-directional antenna 11 and the directional antenna 12 to emit radio waves. Let its transmission frequency be f
t, and the frequency at which the mobile radio returns the transmission is fr, the switch 35 sets the frequency fr =
When measuring the signal of (ft + fi), the signal of the frequency ft from the oscillator 25 via the directional
4 and when measuring the reflected wave (frequency ft), the frequency (ft + fi) through the mixer 38 and the filter 36 is used.
₀ ) is switched to be applied to the mixer 24.
Therefore, the signal of the intermediate frequency fi or fi ₀ mixed by the mixer 24 is input to the measuring unit 40. In this case, ft = 3000 MHz, fi = 10 MHz, fi ₀
= 10 MHz. The filter 20 has a pass band of the frequency fr = ft + fi and ft, and the filters 29 and 31 have a pass band of the frequency ft. It is also possible to run an automobile equipped with a mobile radio, and it is possible to measure the radio wave propagation status together with the azimuth and distance of the mobile radio in a fixed radio.

In the fixed wireless device, a radio wave transmitted from the mobile wireless device is received by the omni-directional antenna 11 and the directional antenna 12, and the directional couplers 13 and 1 receive the radio wave.
The received signal branched by 4 is added to a detection circuit 16 to detect the received signal, and a sidelobe suppression processing circuit 17 compares the reception level of the omnidirectional antenna 11 with the reception level of the directional antenna 12. In this case, the gain of the omnidirectional antenna 11 is set to be smaller than the gain of the main lobe of the directional antenna 12 and larger than the gain of the side lobe. When the reception level is smaller than the reception level by the directional antenna 11, it is determined that the reception is performed by the side lobe, and when the reception level is higher, the reception is determined by the main lobe (main beam) of the directional antenna 12. Therefore, it is possible to accurately identify the azimuth of the mobile radio device by the main lobe, excluding the influence of the side lobe of the directional antenna 12, and
The reception level can be detected by the omnidirectional antenna.

FIG. 3 is a block diagram of a measuring section of the fixed wireless device according to the embodiment of the present invention, wherein 41 is a filter, 42 is an amplifier, 43 and 44 are phase detectors, 45 is an oscillator, and 46 is a directional coupler. , 47 are π / 2 phase shifters, 48 and 49 are squaring circuits, 50 is a register section, 51 is a correlator, 52 is a signal processing section, 53 is a display control section, 54 is a display by a CRT (cathode ray tube) or the like. Reference numeral 55 denotes a comparator, 56 denotes a register, 57 denotes a counter, and 58 denotes a distance indicator. Reference numerals 24 and 30 denote mixers of the transmission / reception section in FIG.

The oscillator 45 has an ultra-stable phase frequency fi.
₀ signal and generating a via a directional coupler 46, which is added to the mixer 30, 38 and phase detector 43, and the signal of frequency fi from the mixer 24 via a filter 41 And the amplified output signal is applied to phase detectors 43 and 44. In the CW mode, the distance measured by the distance measuring means including the comparator 55, the register 56, and the counter 57 is displayed on the distance display 58. In the radar mode and the hopping mode, the squaring circuits 48 and 49, the register unit 50, and the correlator are provided. An azimuth and a distance are displayed by a signal processing unit 51, a signal processing unit 52, a display control unit 53, and a display unit 54.

FIG. 4 is a block diagram of a mobile radio device according to an embodiment of the present invention, which corresponds to the second radio device of FIG. 1, wherein 61 is an antenna, 62 is a circulator, 63 is a filter, 64
Is an amplifier, 65 is an attenuator, 66 is a delay circuit, 67 is a decoder, 68 is a changeover switch, 69 is an oscillator, 70 is a mixer, 71 is a filter, 72 is an amplifier, 73 is a filter, and amplifiers 64 and 72 are It is a linear amplifier.

A radio wave from a fixed wireless device is received by an antenna 61, and a received signal having a frequency ft (= 3000 MHz) is received from a circulator 62 by a filter 63, an amplifier 64,
The signal is added to the mixer 70 via the attenuator 65 and the changeover switch 68, mixed with the signal of the frequency fi (= 10 MHz) of the oscillator 69, and the frequency fr = ft + fi (= 3010 MHz) via the filter 71, the amplifier 72, and the filter 73. Is transmitted from the antenna 61 via the circulator 62. That is, the radio wave from the fixed wireless device is frequency-converted and transmitted back, and the propagation distance of the radio wave is measured by the measuring unit of the fixed wireless device.

The decoder 67 decodes a control code from the fixed wireless device and inserts a delay circuit 66,
By controlling the changeover switch 68, the output signal of the amplifier 64 is applied to the mixer 70 via the delay circuit 66. That is, the return time of the mobile wireless device can be lengthened, and the apparent radio wave propagation distance between the fixed wireless device and the mobile wireless device can be increased.

In the CW mode, the modulator 27 and the demodulator 2
Numeral 3 is a control for a through state, in which the output signal of the oscillator 25 is transmitted through the directional coupler 26, the modulator 27, the changeover switch 28, the filter 29, the circulator 19, the changeover switch 15 and the directional coupler 13. And transmits it from the omnidirectional antenna 11 or the directional antenna 12 as the frequency ft. The mobile radio has the frequency ft as described above.
Is converted into a frequency fr = ft + fi and transmitted by return. The fixed wireless device receives the signal through the omnidirectional antenna 11 and the directional antenna 12, and, as described above, uses the detection circuit 16 and the sidelobe suppression processing circuit 17 to compare the reception level with the omnidirectional antenna 11. The direction of the main lobe (main beam) at which the reception level of the directional antenna 12 increases can be identified as the direction of the mobile radio.

FIG. 5 is an explanatory diagram of the reception correlation output. The correlation of the reception signal with respect to the transmission signal changes according to the elapsed time (distance) from the transmission time, and the reception correlation output increases first because of the shortest propagation wave. In general, the time at that time (distance R ₀ ) is the propagation distance of the direct wave between the fixed wireless device and the mobile wireless device. The reason why the reception correlation output in the subsequent time (distance R ₁ ) increases is that
Due reflected wave 1 shows propagation distance that R ₁ is long due to the reflected wave from the propagation distance R ₀ by the direct wave. Similarly, the distance R _{2 at} which the reception correlation output increases due to another reflected wave 2 indicates the propagation distance of the reflected wave 2. Therefore, it is possible to measure not only the propagation distance of the direct wave between the fixed wireless device and the mobile wireless device but also the reflection point of the reflector such as a high-rise building. In some cases, the reflected wave 1 or 2 may be larger than the reception correlation output of the direct wave.

In the measuring section 40 of the fixed radio, the mixed output signal of the mixer 24 is applied to the phase detectors 43 and 44 via the filter 41 and the amplifier 42, and the .pi. / 2 Is detected by a signal having a phase difference of
In the case where only one of the phase detectors 43 and 44 is used, a phase blind in which the phase detection output is lost occurs. A means for performing distance measurement using the phase blind and a distance in which the phase blind is eliminated are used. There is a means to make measurements.

The means for measuring the distance without the phase blind includes two phase detectors 43 and 44, squaring circuits 48 and 49, a register unit 50, and a signal processing unit 52. At 43 and 44, phase detection is performed by carrier waves having a phase difference of π / 2, respectively, so that one is an output of Asin θ and the other is an output of Acos θ, which is converted into digital signals by squaring circuits 48 and 49. Squared and synthesized in the register unit 50, (A
sinθ) ² + (Acosθ) from a ² = A, no signals A related to the phase θ is obtained.

The signal A is subjected to signal processing on the frequency axis by a fast Fourier transform or the like in a signal processing section 52 to obtain a distance. For example, as shown in FIG. 5, looking at the correlation between the transmission signal and the reception signal based on the transmission time, the reception correlation output changes depending on the distance (time from the transmission timing), and the reception correlation output by the direct wave is changed. The maximum point can be defined as the propagation distance R _{0 of the} radio wave. The propagation distance R ₀ of the radio wave in this case indicates the distance reciprocated between the fixed wireless device and the mobile wireless device. Therefore, the actual distance between the fixed wireless device and the mobile wireless device is R _0/2 . , The distance resolution can be improved. When the mobile radio is moving, the output signal has the beat of the Doppler frequency component, and can be efficiently separated by a filter bank or the like in the signal processing unit 52.

[0033] The means for performing distance measurement by utilizing the phase blinds, a comparator 55, a register 56, consists of a counter 57, f the transmission frequency, for example, from f ₁
By changing to ₂ and observing the phase change, it counts how many times the phase blind has occurred,
As the transmission frequency, for example, the oscillation frequency of the oscillator 25 can be swept or switched by a control signal from the control circuit 18. (A) the frequency f ₁ of the signal waveform of Matazu 6, the (b) and the signal waveform of the frequency f _2, the speed of light c, ₁ wavelength lambda, when a _{λ 2, f 1 = c /} λ 1, f ₂ = c /
λ ₂ and λ ₂ = λ ₁ + Δλ _D. Wave number difference N
Is N = (R / λ ₁ ) −, where R is the propagation distance of the radio wave.
(R / λ ₂ ) = (R / λ ₁ ) − (R / λ ₁ + Δλ _D ). That is, when the frequency is changed from the frequency f ₁ by the counter 57 and the zero cross point reaching the frequency f ₂ is counted and the wave number difference N is obtained, the wavelengths λ ₁ and λ ₂ are known, so that the propagation distance R Can be derived. In this case as well, the propagation distance of the radio wave that travels back and forth between the fixed wireless device and the mobile wireless device is measured, so that the distance resolution can be improved. Further, the distance display 58 displays the propagation distance based on the average value obtained by repeating this measurement a predetermined number of times. In addition, the propagation distance information is added to the display control unit 53, and the display control unit 53 can display the azimuth and the distance on the display unit 54.

Also, the number of reciprocations of radio waves between the fixed radio and the mobile radio can be increased. In this case, after the output signal of the oscillator 25 is transmitted as a pulse, the changeover switch 28 is set to the amplifier. Switch to the 32 side. One branched from the directional coupler 22 is applied to the terminal 37 for measurement of a reception level, for example, to a spectrum analyzer, and the other is added to the mixer 30 as a reception signal. The signal is mixed with a signal branched from the signal by a directional coupler 46 and converted into a signal having a frequency ft.
9, circulator 19, changeover switch 15, omnidirectional antenna 11 via directional coupler 13 or directional antenna 12 via changeover switch 15, directional coupler 14
Send from.

Since the mobile radio device converts the received signal of the frequency ft to the frequency fr and transmits the signal back, the mobile radio device and the fixed radio device are switched until the switch 28 of the fixed radio device is switched to the modulator 27 side. Transmission and reception are repeatedly performed with the wireless device. That is, it can be measured after a propagation time that is a multiple of the reciprocating propagation distance of the radio wave between the fixed wireless device and the mobile wireless device. Further, since the delay time of the delay circuit 66 of the mobile wireless device is set in advance, the control code is modulated by the modulator 27 by the modulation control unit 33 or the like of the fixed wireless device and transmitted. The control code is identified by decoding by the decoder 65, the switching of the changeover switch 68 is controlled, and the reception signal is transmitted back through the delay circuit 66, so that the propagation time of the radio wave can be apparently lengthened. That is, it is not easy to separate and measure a short-range reflected wave, but by making the propagation time seemingly longer, it becomes similar to a long-range reflected wave, so that the propagation distance difference with the direct wave is increased. be able to. In the case of repeated transmission and reception multiple times, the propagation time is similarly extended,
The effect of the short-range reflected wave can be easily identified.

In the case of the radar mode, the code generator 3
4 generates a pseudo-noise (PN) code having a large autocorrelation, and controls the modulator 27 from the modulation control unit 33.
The output signal of the oscillator 25 is phase-modulated and transmitted from the omnidirectional antenna 11 as in the case of the CW mode. The mobile radio transmits and returns the received signal irrespective of the mode, and the fixed radio receives the non-directional antenna 11 and the directional antenna 12 and performs main lobe (main beam) by side lobe suppression processing. ) By controlling the directional antenna 12 to receive the signal
The orientation of the mobile radio can be identified. Then, the received signal is phase-shifted by the phase shifter 23 and added to the measuring section 40 via the mixer 24.

In the measuring section 40, the squaring circuits 48, 4
9 converts the phase detection output signal into a digital signal, squares it, synthesizes it by the register unit 50 to obtain a received signal irrespective of the phase θ, and the correlator 51 determines the propagation distance of the radio wave by the time when the autocorrelation is maximized. Can be requested. FIG. 7 is a main block diagram of a signal extracting circuit for extracting a received signal having a large autocorrelation. As a pseudo noise generator 80, a 5-bit shift register 81 and an exclusive OR circuit 82 are provided. An example is shown in which the intermediate stage and the output stage are connected to an exclusive OR circuit 82 and the output signal of the exclusive OR circuit 82 is input to the shift register 81. When each stage is set to "1" at the time of activation, A pseudo noise (PN) code having a period of 31 bits can be obtained. This code is called the M-sequence code because it is the longest code as compared with the case where feedback is made from another stage.
The carrier from 5 is modulated in modulator 27.

Since the reception code is set in the register unit 50, the pseudo noise generator 80 is started at the transmission timing, and the reception code set in the register unit 50 and the pseudo noise generator are set. The output code 80 is correlated with the exclusive OR circuit 83, and the time at which the maximum correlation is obtained is obtained by switching the shift stage of the shift register constituting the register unit 50 or the number of shift clocks. , That is, the propagation distance is obtained.
Therefore, the configuration of the signal extraction circuit shown in FIG. 7 is used as the correlator 51 of the measurement unit 40, and the pseudo noise generator 80 is used as the code generation unit 3.
4 can be set. Note that a code having a larger number of bits can of course be used as the pseudo noise code.

As a code, a Barker code known as a pulse compression radar can be used.
FIG. 8 is an explanatory diagram of a signal extraction circuit when a 5-bit Barker code is used. The 5-bit Barker code set in the register unit 50 is input to the shift register 85. The output of each stage of the shift register 85 is input to an adder (Σ) 87 and added. In that case, an inverter 86 is connected between the shift register 85 and the adder 87 corresponding to the Barker code.

The 5-bit Barker code is (+1,-
1, +1, +1, +1), and the signals input to the adder 87 from each stage of the shift register 85 are represented by A to E. The following table shows changes in A to E with the passage of time. .
Then, the output signal of the adder 87 is indicated by Σ.
That is, since A = + 1 and B to E = 0 at first, the added output signal Σ becomes +1. Next, A = -1, B = + 1,
Since C to E = 0, the addition output signal Σ becomes 0. Similarly, when A to E = + 1 (D becomes +1 by inverting −1), the addition output signal な る becomes +5. At this time, the autocorrelation becomes maximum, so that a 5-bit Barker code can be extracted. By measuring the time until the Barker code is extracted using a shift clock or the like, the propagation time of the radio wave, that is, the propagation distance can be obtained. Such a signal extraction circuit is used as the correlator 51 of the measurement unit 40, and the code generation unit 34 generates a 5-bit Barker code. Of course, it is also possible to use a Barker code of another number of bits.

Using a plurality of types of pseudo-noise (PN) codes or Barker codes, a code having a predetermined cycle is transmitted, and then another code is transmitted in a predetermined cycle, which is sequentially repeated. Change and send,
The propagation distance of the radio wave can be measured by distinguishing the reflected wave and the direct wave.

In the case of the hopping mode, the oscillator 25
Is controlled by the control circuit 18 to perform frequency hopping. In this case, by configuring the oscillator 25 with, for example, a frequency synthesizer, highly stable frequency hopping can be performed. This hopping mode allows randomization of bit errors and the like in selective fading. Therefore, by averaging signal detection errors when a code with a large autocorrelation is used, the reliability of propagation distance measurement can be improved. Performance can be improved. It is also possible to combine different types of codes with frequency hopping.

The phase shifter 23 of the fixed radio sets the phase modulation opposite to the transmission modulation (demodulation) or adjusts the initial phase of the measurement to an appropriate state depending on the position of the mobile radio to be measured. When necessary (initial phase adjustment), modulation (or demodulation) is performed, and a desired intermediate frequency signal is input to the measurement unit 40.

[0044]

As described above, according to the present invention, the first wireless device 1 is a fixed wireless device, and the signal transmitted from the first wireless device 1 is transmitted to the second wireless device as a mobile wireless device. 2 for linear amplification, frequency conversion, and return transmission (repeater). The return transmission signal is received by the first wireless device 1, and the direction of the second wireless device 2, the propagation distance of the radio wave, the reception The level and the like are measured by the measuring unit 5, and the radio wave propagation path is enhanced by repeater transmission, and the actual distance between the first wireless device 1 and the second wireless device 2 is doubled or Since the signal passes through the propagation distance of a radio wave that is a multiple of 2, the advantage is that the ability to resolve the distance can be improved on the time axis, and the second wireless device 2 has the advantage of requiring a simple configuration. is there. Also, as the number of times of return transmission / reception between the first and second wireless devices 1 and 2 is increased, the apparent radio wave propagation distance can be increased and the distance resolution can be further improved.

Only when the reception level of the directional antenna is higher than the reception level of the omnidirectional antenna of the fixed first radio 1, it is determined that the reception signal is the reception signal of the main lobe of the directional antenna. The lobe can be suppressed, and the azimuth of the second wireless device on the moving side can be accurately measured.

Since the wave number ratio within the propagation distance can be obtained by sweeping or switching the transmission frequency, the propagation distance of the radio wave can be easily measured. When a code having a large autocorrelation is used, the propagation time of a radio wave can be easily and accurately measured based on the time at which the correlation between the transmission signal and the reception signal is obtained, so that the distance resolution can be improved. There are advantages. Therefore, there is an advantage that the radio wave environment measurement for installing a base station in a system such as a mobile phone can be performed accurately and easily.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a block diagram of a transmission / reception unit of the fixed wireless device according to the embodiment of the present invention.

FIG. 3 is a block diagram of a measuring unit of the fixed wireless device according to the embodiment of the present invention.

FIG. 4 is a block diagram of a mobile wireless device according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of a reception correlation output.

FIG. 6 is a diagram illustrating the relationship between wavelength and frequency.

FIG. 7 is a main block diagram of a signal extraction circuit.

FIG. 8 is an explanatory diagram of a signal extraction circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first wireless device 2 second wireless device 3 transmitting / receiving unit 4 transmitting / receiving unit 5 measuring unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04B 17/00 G01R 29/08

Claims (4)

(57) [Claims] [Claim 1, further comprising a first, second radio, the second radio comprises a transceiver unit having a relay means for transmitting the received folded signals of the first radio or al the first radio, a transceiver for transmitting and receiving signals, based on a more folded signal to said transmission reception unit or we transmitted signal and the second radio, radio wave propagation distance and the reception level and a measuring unit for measuring the like, the transmission and reception unit of the first radio, the second radio
A relay that receives a more folded signal and sends it again.
Means, and the measuring unit is set in advance by the transmitting / receiving unit.
The received signal after the specified number of transmission / reception
Based on the transmitted signal, radio wave propagation distance, reception level, etc.
A radio wave environment measuring device, comprising: means for measuring an electric wave. 2. The apparatus according to claim 1 , further comprising first and second radios , wherein said second radio receives a signal from said first radio.
A transmission / reception unit having relay means for transmitting
And, wherein the first radio comprises a transceiver for transmitting and receiving signals, said
Fold by the signal transmitted from the transmitting / receiving unit and the second radio
Based on the returned signal, radio wave propagation distance, reception level, etc.
And a measurement unit for measuring the distance between the first wireless device and the non-directional antenna.
And a directional antenna.
The receiving unit is configured so that the reception level of the directional antenna is
When the reception level is larger than the omnidirectional antenna,
Side lobe suppression for determining received signal by inlobe
Means for receiving a signal folded back by said second radio
And a relay means for transmitting the data again
Transmits and receives a preset number of times by the transmitting and receiving unit.
Based on the received signal after performing and the signal transmitted first,
A radio wave environment measuring device having means for measuring a propagation distance of a radio wave, a reception level, and the like . 3. The apparatus according to claim 1 , further comprising first and second radios , wherein said second radio receives a signal from said first radio.
A transmission / reception unit having relay means for transmitting
And, wherein the first radio comprises a transceiver for transmitting and receiving signals, said
Fold by the signal transmitted from the transmitting / receiving unit and the second radio
Based on the returned signal, radio wave propagation distance, reception level, etc.
And a measuring unit for measuring the first wireless device, wherein the transmitting and receiving unit of the first wireless device is connected to the second wireless device
A relay that receives a more folded signal and sends it again.
Means and means for switching or sweeping the transmission signal frequency
And the measuring unit is turned back from the second wireless device.
Based on the change in the phase difference between the transmitted signal and the transmission signal.
A radio wave environment measuring device having means for measuring a wave propagation distance, a reception level, and the like . 4. A wireless communication system comprising first and second wireless devices , wherein the second wireless device receives a signal from the first wireless device.
A transmission / reception unit having relay means for transmitting
And, wherein the first radio comprises a transceiver for transmitting and receiving signals, said
Fold by the signal transmitted from the transmitting / receiving unit and the second radio
Based on the returned signal, radio wave propagation distance, reception level, etc.
And a measuring unit for measuring the first wireless device, wherein the transmitting and receiving unit of the first wireless device is connected to the second wireless device
A relay that receives a more folded signal and sends it again.
Means, and the measuring unit is set in advance by the transmitting / receiving unit.
The received signal after the specified number of transmission / reception
Based on the transmitted signal, radio wave propagation distance, reception level, etc.
And the transmission / reception unit of the second wireless device performs the return transmission.
A radio wave environment measuring device having a delay circuit for controlling a repeat transmission time .