JP2002246825A - Array antenna system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To arbitrarily and easily change the correction parameter of an array antenna system. SOLUTION: This array antenna system is provided with a beam forming means (BFN) 2 for distributing an input signal to at least two signals, and for applying prescribed phase shift and amplitude to the distributed signals, amplifying means 3-1 to 3-4 for amplifying the signals outputted from the BFN 2, and a plurality of antenna elements 7-1 to 7-4 for outputting the beams of the signals supplied from the amplifying means so that a synthesized beam with prescribed directivity can be formed. This array antenna device is also provided with a phase amplitude control means for extracting the signals to be supplied to the antenna elements 7-1 to 7-4 respectively by directional couplers 4-1 to 4-4, and for monitoring the phase shift value and amplitude of the signals, and for, when they exceed a preliminarily set range, controlling the BFN 2 so that the phase shift and amplitude to be applied to the distributed signals can be adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an array antenna device, and more particularly to a technique for correcting a variation in a power supply signal supplied to a plurality of antenna elements.

[0002]

2. Description of the Related Art A conventional array antenna apparatus includes a beam forming network (BFN) having a signal from a transmitter as an input signal, an amplifier for amplifying a plurality of signals output from the BFN, and a signal supplied from the amplifier. And a plurality of antenna elements that emit a beam corresponding to the above. In this array antenna device, the amplitude and phase shift amount (hereinafter referred to as the signal) of a signal fed from the BFN to each antenna element via an amplifier so that the beam radiated from each antenna element has the same phase on a plane orthogonal to the directing direction. , "Phase") to emit a combined beam having a desired directivity.

A BFN is constituted by a variable delay line, a phase shifter, and the like in which the amplitude of an output signal is determined by an attenuator and the phase of the output signal is determined by the length of a line from an input terminal to an output terminal. It had been. Further, the amplifier was constituted by a solid-state power amplifier or the like.

However, the nonlinear characteristic of the amplifier and B
Since the characteristics of elements constituting the FN and the amplifier vary, the conventional array antenna apparatus uses a correction for storing a correction parameter for setting the characteristic within a predetermined value for each device such as the BFN and the amplifier. A table is provided, and adjustments are made before the antenna operation based on the correction parameters so that the characteristics of the BFN and the amplifier fall within a predetermined range.

[0005]

SUMMARY OF THE INVENTION The present inventor has found the following problems as a result of studying the prior art. Since the element characteristics of the BFN and the amplifier included in the conventional array antenna apparatus change due to aging, temperature environment, and the like, it is necessary to change the correction values stored in the correction table as needed. Was.

However, as described above, the conventional array antenna apparatus is configured to obtain a combined beam having a desired directivity by combining beams radiated from each antenna element in space. For this, B
In order to adjust the FN and the amplifier and to grasp the state, it is necessary to measure by combining a large-scale anechoic chamber or a small-scale anechoic chamber with a near-field device. Effort and time were required.

[0007] Further, when correction is performed for each BFN, amplifier, or the like, errors in individual devices accumulate.
In the conventional array antenna device, it was necessary to provide some redundancy.

An object of the present invention is to provide a technique capable of arbitrarily and easily changing a correction parameter according to a characteristic change of a device constituting an array antenna device.

Another object of the present invention is to provide a technique capable of improving the reliability of an array antenna device. The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0010]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows. (1) beam forming means for distributing an input signal into two or more signals and giving a predetermined phase shift and amplitude to the divided signal; amplifying means for amplifying a signal output from the beam forming means; A plurality of antenna elements that output a beam of a signal fed from the amplifying unit,
In an array antenna device that forms a combined beam having directivity according to the phase shift amount and the amplitude, an extraction unit that extracts a signal supplied to the antenna element, and a phase shift amount of a signal supplied to the antenna element. A phase amplitude control means for monitoring the amplitude and controlling the beam forming means and adjusting the phase shift and amplitude applied to the input signal when the phase shift amount and the amplitude exceed a preset range.

(2) In the array antenna device described in (1) above, the beam forming means changes the amplitude of the distributed input signal according to the control output of the phase and amplitude control means. And a phase shifter that varies a phase shift amount of the distributed input signal according to a control output of the control means.

(3) In the array antenna device according to the above (1) or (2), the control means may use any one of the plurality of signals extracted by the extraction means as a reference signal, and Means for comparing the phase shift amount and the amplitude of the signal with another signal, and controlling the phase shift amount and / or the amplitude of the beam forming means based on the comparison result.

According to the above-mentioned means, the phase and amplitude control means monitors the amount of phase shift and the amplitude of the signal supplied to the antenna element extracted by the extraction means. At this time, when the phase shift amount and the amplitude exceed a preset range, the phase and amplitude control means controls the beam forming means to adjust the phase shift amount and the amplitude given to each of the distributed signals. Even when the characteristics (phase-amplitude non-linear characteristics and element characteristics) of the amplifying means and beam forming means constituting the array antenna apparatus fluctuate due to aging and environmental changes, correction according to the characteristic fluctuations is easily performed. be able to. At this time, the phase amplitude control means constantly monitors the phase shift amount and amplitude of the signal supplied to the antenna element extracted by the extraction means,
Correction according to the characteristic fluctuation can be performed in real time.

Further, by performing the correction only when the CW signal is input as the input signal, the correction according to the characteristic fluctuation can be arbitrarily controlled. As a result, the reliability of the array antenna device can be improved.

Further, an amplitude control means for varying the amplitude of the divided input signal according to a control output of the phase and amplitude control means, and a phase shift of the divided input signal according to a control output of the phase and amplitude control means. By providing the beam forming means with a phase shifter for varying the amount, in addition to the original function of the beam forming means, the beam forming means and the amplifier function as a compensator for the phase-amplitude non-linear characteristics and the element characteristics. It can be added to the forming means.

Further, the phase and amplitude control means uses any one of the power supply signals extracted by the extraction means as a reference signal and compares the phase shift amount and the amplitude between the reference power supply signal and another power supply signal. With this configuration, an effect that the device configuration can be simplified can be obtained.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings together with embodiments (examples) of the present invention. In all the drawings for describing the embodiments of the present invention, components having the same functions are denoted by the same reference numerals, and their repeated description will be omitted.

(First Embodiment) FIG. 1 is a diagram for explaining a schematic configuration of an array antenna device according to a first embodiment of the present invention. However, in the following description, a case where there are four antenna elements will be described for the sake of simplicity.
Needless to say, the number of antenna elements only needs to be two or more, and the number of BFNs, the number of amplifiers, and the like also increase or decrease according to the number of antenna elements.

In FIG. 1, a BFN (beam forming network, beam forming means) 2 includes an input port 9.
Is a device for distributing an input signal input from the CDMA into four signals having different phases and amplitudes and outputting the signals to four output ports 10-1 to 10-4. For example, a known IQ vector modulator, amplitude controller, and distributor Consists of BFN2
Is configured to correct the phase and amplitude of the four signals distributed according to the control signal from the interface 8. The detailed configuration of the BFN 2 will be described later. The input signal input from the input port 9 is supplied from, for example, a transmitter (not shown).

The amplifiers 3-1 to 3-4 are well-known amplifiers for respectively amplifying four signals output from the BFN2, and include, for example, a well-known solid-state power amplifier or the like.

The phase / amplitude detecting unit 5 is configured to output each of the amplifiers 3 extracted from the directional couplers (extraction means) 4-1 to 4-4.
-1 to 3-4 to corresponding antenna elements 7-1 to 7-4
Out of the signals supplied to the first and second signals, and compares the phase and amplitude of one signal set in advance with the other signals, and outputs the comparison data to the beam control computer 6 at the subsequent stage. The detailed configuration of the phase and amplitude detector 5 will be described later.

The beam control computer 6 has a terminal 16
Based on the comparison data input from the phase / amplitude detecting unit 5 via the interface, it is determined whether the phase and the amplitude are within a preset range (within an error range). Means for controlling the phase and amplitude of the BFN 2 by, for example, a known information processing apparatus, and a determination program and a control program that operate on the information processing apparatus. The beam control computer 6
Is configured to control the phase and amplitude given to the input signal by the BFN 2 via the interface 8 to control the radiation direction, directional characteristics, and the like of the combined beam. Further, the beam controlling computer 6 controls the control table data describing the phase and amplitude given to the input signal by the BFN 2 according to the radiation direction and the directional characteristics of the combined beam, and the error range of the phase difference and the amplitude difference. It has table data for comparison described above, and table data for correction (correction parameters) describing the amount of phase and the amount of amplitude for correcting the table data for control, and is described in each table data. The configuration is such that the phase and amplitude of BFN2 are determined based on the phase and amplitude. However, in the first embodiment, the input signal input from terminal 1 is CW
In the case of a (Continuous Wave) signal, the phase and amplitude are determined and corrected, and in the case of a modulated signal, the beam control is also corrected.

As described above, in the first embodiment, the phase / amplitude control means is formed by the phase / amplitude detection unit 5, the beam control computer 6, and the interface 8.

Next, a phase and amplitude correction operation in the array antenna device of the first embodiment when a CW signal is input will be described with reference to FIG.

When a CW signal is input from a terminal 1 as an input signal, the BFN 2 distributes the CW signal into four signals corresponding to the four antenna elements 7-1 to 7-4. After the phase and amplitude set at the time of input of the CW signal are given by BFN2 to each of the four divided signals, each signal is output to output ports 10-1 to 10-1.
-4 is output. However, the phase and amplitude at this time are based on correction table data before the CW signal is input.

The signals output from the output ports 10-1 to 10-4 are amplified by the corresponding amplifiers 3-1 to 3-4, and then supplied to the antenna elements 7-1 to 7-4. At this time, a part of the signal fed to the antenna elements 7-1 to 7-4 is extracted by the directional couplers 4-1 to 4-4, and the phase and the amplitude are outputted through the terminals 13-1 to 13-4. It is input to the detection unit 5.

The phase and amplitude of the power supply signal input to the phase and amplitude detector 5 are compared by the phase and amplitude detector 5, and the resulting phase and amplitude comparison data is
It is input to the beam control computer 6.

The beam control computer 6 first calculates the phase and amplitude of each feed signal input to the antenna elements 7-1 to 7-4 from the comparison data. Next, the beam control computer 6 compares the phase and amplitude of the obtained power supply signal with the value of the table data for error. here,
If the error is smaller than the error range in the error table data, the following comparison is performed. On the other hand, if the error is larger than the error range in the error table data, the beam control computer 6 performs the following comparison after correcting the correction table data.

When the correction table data is corrected, the beam control computer 6 firstly corrects the corrected phase or amplitude based on the corrected correction table data and the control table data. Calculate. Next, the beam control computer 6 calculates a corrected control value necessary to realize the corrected phase and amplitude, and controls the BFN 2 based on the corrected control value via the interface 8. Do.

Therefore, the corrected phase and amplitude are applied to the input signal input after this correction. That is, the BFN2, the amplifiers 3-1 to 3-4, the amplifiers 3-1 to 3-4, and the antenna elements 7-1 to 4-1.
The phase and amplitude fluctuations caused by the characteristic fluctuations occurring in any of the transmission paths connecting the antenna 7-4 to the antenna element 7-4 are corrected, and the corrected power supply signals are supplied to the antenna elements 7-1 to 7-4. Therefore, the directivity of the combined beam can be corrected with high accuracy. However, depending on the mounting position of the directional couplers 4-1 to 4-4, a power supply signal is transmitted through a transmission path connecting each of the amplifiers 3-1 to 3-4 and each of the antenna elements 7-1 to 7-4. Needless to say, the correction can be made in consideration of the influence. Further, by disposing the mounting positions of the directional couplers 4-1 to 4-4 in the vicinity of the antenna elements 7-1 to 7-4, it is possible to easily find a failure or the like occurring in the transmission path. The effect is obtained.

In particular, in the first embodiment, while the CW signal is being input, monitoring and correction of the power supply signal, that is, correction of the correction table data by the beam control computer 6 is continued. Therefore, during the period when the CW signal is being input, if the corrected power supply signal again has a phase and amplitude exceeding the error range, the correction is immediately performed by the above-described procedure.

As described above, in the first embodiment, the phase / amplitude detecting section 5 and the phase / amplitude detecting section 5 are controlled so that the phase and amplitude of the power supply signal supplied to the antenna elements 7-1 to 7-4 fall within a preset error range. An error detected by the beam control computer 6 is fed back to the BFN 2 and corrected.

Therefore, the BFN2 and the amplifiers 3-1 to 3-
4 can quickly compensate for the non-linear characteristics and device characteristics. That is, it is possible to arbitrarily and easily change the correction parameter according to the characteristic fluctuation of the equipment constituting the array antenna device. As a result, the reliability of the array antenna device can be improved.

FIG. 2 is a diagram for explaining a schematic configuration of the BFN according to the first embodiment. However, the amplitude controller and IQ
The number of vector modulators is appropriately changed according to the number of antenna elements, that is, the number of input signals to be distributed.

As is apparent from FIG. 2, the BFN 2 of the first embodiment converts the input signal input from the input port 9 into four.
A well-known distributing means (not shown) for distributing the signal to the system, and four amplitude controllers (amplitude controlling means) 12-1 to 12- for controlling the input signal after distribution, that is, the distribution signal amplitude in accordance with a control signal from the interface 8; And four IQ vector modulators 11-1 to 11- as phase shifters for controlling the phase between distribution signals by giving a time delay according to the control signal from the interface 8 to the signal whose amplitude has been adjusted. And 4.

Each of the amplitude controllers 12-1 to 12-4 is, for example, a known amplifier whose amplification factor can be controlled by an external control input or a known attenuator whose attenuation factor can be controlled by an external control input. In the first embodiment, the amplifiers 3-1 to 3-1
The beam control computer 6 is controlled so that the amplitude of each power supply signal output from 3-4 falls within a preset error range.
Is configured to control the amplitude or attenuation of the amplitude controllers 12-1 to 12-4 to control the amplitude of the input signal. That is, in the first embodiment, a change in the amplification factor caused by a change in element characteristics between the BFN 2 and the amplifiers 3-1 to 3-4 due to a change over time or a change in the temperature environment, etc. The configuration is such that the correction is made by the change in the amplitude of 12-4. However, in the first embodiment, when the phase is controlled by the IQ vector modulators 11-1 to 11-4, the amplitude changes together with the phase. Controller 12
This is performed in -1 to 12-4.

The IQ vector modulators 11-1 to 11-11
-4 are amplitude controllers 12-1 to 12-1 according to the values of the in-phase control input I and the quadrature-phase control input Q input from outside.
This is a known modulator that changes the phase of a signal input from 2-4. In the first embodiment, the amplitude controller 12-
Similarly to 1 to 12-4, the IQ vector modulators 11-1 to 11-4 operate so that the phases of the power supply signals output from the amplifiers 3-1 to 3-4 are within a predetermined error range. The configuration is such that the phase deformation is controlled. That is, in the first embodiment, a change in phase caused by a change in element characteristics between the BFN 2 and the amplifiers 3-1 to 3-4 due to aging, a change in temperature environment, and the like is determined by the IQ vector modulator 11-.
The configuration is such that the correction is made by the phase deformation by 1 to 11-4.

In the BFN 2 of the first embodiment, the phase control and the amplitude control are performed by the IQ vector modulator 11-
1 to 11-4 and the amplitude controllers 12-1 to 12-4 are performed in a distributed manner. However, the present invention is not limited to this. For example, an IQ vector modulator capable of amplitude control is used. BFN2 amplitude controllers 12-1 to 12-12
Needless to say, a configuration not using -4 may be used.

In particular, by using an IQ vector modulator, which is an infinite phase shifter capable of independently and continuously changing the amplitude and phase of the modulated signal, the amount of phase shift, ie, phase And the amplitude can be changed continuously with high precision.

As a result, the correction of the array antenna device can be performed with higher precision and continuously, so that the directivity of the combined beam can be corrected with higher precision.

FIG. 3 is a diagram for explaining a schematic configuration of the phase and amplitude detector 5 according to the first embodiment. However, the number of inputs of the switch is appropriately changed according to the number of antenna elements, that is, the number of feed signals.

In FIG. 3, the switch 14 is connected to each terminal 1
4-input 1 for selecting one of the four power supply signals input through 3-1 to 13-4 and outputting the selected power supply signal to the network analyzer 15 as a test signal
It is a well-known switch for output. The switch 14 is 4
It has a selection input (not shown) for switching which of the inputs is output. In particular, in the first embodiment,
This selection input is connected to an output port (not shown) of the beam control computer 6, and is configured to switch which of the four inputs is output according to a selection instruction from the beam control computer 6.

The network analyzer 15 uses a power supply signal input via a preset terminal 13-1 among the four input terminals as a reference signal, and outputs a signal between the reference signal and the test signal from the switch 14. Is a well-known network analyzer that compares the phase and the amplitude with each other and outputs the obtained data (s parameter).

In the first embodiment, the power supply signal input from the terminal 13-1 is branched into two, one of the power supply signals is input to the switch 14, and the other is used as a reference signal. Is bypassed and input directly to the network analyzer 15. Therefore, the beam control computer 6 is connected to the terminal 13
By selecting −1, the power supply signal bypassing the switch 14 as a reference signal and the power supply signal via the switch 14 as a test signal are input to the network analyzer 15.

As a result, the network analyzer 15 can calibrate the reference signal system and the test signal system. That is, for example, even when an amplifier for amplifying an input signal is provided at the reference signal input and the test signal input of the network analyzer 15, the network analyzer 15 can perform accurate phase and amplitude comparison.

Therefore, in order to reduce the impedance mismatch to the amplifiers 3-1 to 3-4, etc., the directional coupler 4
Even when the coupling degree of -1 to 4-4 is reduced, an amplifier for amplifying an input signal can be provided at the reference signal input and the test signal input of the network analyzer 15, so that a difference between the reference signal and the test signal can be obtained. Can compare the phase and the amplitude with sufficient accuracy.

As described above, in the array antenna apparatus according to the first embodiment, when a CW signal is input from terminal 1, first, phase and amplitude detector 5 causes directional couplers 4-1 to 4-1 to -4 to -4.
-4, outputs comparison data of the phase and the amplitude of the power supply signal supplied to each of the antenna elements 7-1 to 7-4 to the beam control computer 6 based on the power supply signal extracted.

Next, the beam control computer 6 calculates the phase and amplitude of each power supply signal. Next, the beam control computer 6 compares the obtained phase and amplitude of the power supply signal with the value of the error table data, and when this error is larger than the error range in the error table data, Correct the correction table data. When the correction table data is corrected, the beam control computer 6 calculates the corrected phase or amplitude based on the corrected correction table data and the control table data, and calculates the corrected phase or amplitude. The modified control value required to realize the phase and amplitude is calculated, and the BF based on the modified control value via the interface 8 is calculated.
Control of N2 is performed.

By this control, the BFN 2 adjusts the phase and amplitude given to each of the divided signals.
Even when the characteristics (phase-amplitude non-linear characteristics and element characteristics) of the amplifiers 3-1 to 3-4 and BFN2 constituting the array antenna device change with aging and environmental changes,
Correction according to the characteristic fluctuation can be easily performed. As a result, the reliability of the array antenna device can be improved.

As described above, the array antenna device of the first embodiment is based on the feedback from the respective feed signals output from the four amplifiers 3-1 to 3-4.
The BFN 2 and the amplifiers 3-1 to 3-4 are configured to adjust a change over time in element characteristics and a change due to a temperature environment or the like by the phase and amplitude of the BFN 2.

In the first embodiment, the control table data for controlling the BFN 2 and the BFN 2 and the amplifiers 3-1 to 3-
4, the data is managed separately from the correction table data for compensating for the non-linear characteristics and element characteristics generated in the device 4. However, the present invention is not limited to this configuration. It goes without saying that the data for compensating the non-linear characteristic and the element characteristic may be added to the BFN2 control table data.

(Embodiment 2) FIG. 4 is a diagram for explaining a schematic configuration of an array antenna apparatus according to Embodiment 2 of the present invention. However, the array antenna apparatus according to the second embodiment detects a CW signal frequency-multiplexed with a modulation signal,
The operation other than performing the correction according to the fluctuation caused in the characteristics of the amplifiers 3-1 to 3-4 and BFN2 constituting the array antenna device is the same as that of the array antenna device of the first embodiment. Therefore, in the following description, only the configuration and operation of the band-pass filter (BPF) for detecting the CW signal frequency-multiplexed with the modulation signal will be described in detail.

In FIG. 4, a band-pass filter (hereinafter, referred to as a band-pass filter)
18-1 to 18-4 are well-known band-pass filters that pass signals in a preset frequency range. In the second embodiment, CW signals frequency-multiplexed with a power supply signal are described. The passband is set to the frequency of.

As is apparent from FIG. 4, in the array antenna apparatus according to the second embodiment, the respective outputs from directional couplers 4-1 to 4-4 are the inputs to BPFs 18-1 to 18-4. Connected to terminals 17-1 to 17-4. This B
Outputs of the PFs 18-1 to 18-4 are connected to terminals 13-1 to 13-4 connected to inputs of the phase and amplitude detector 5. Other configurations are the same as those of the first embodiment.

The array antenna device according to the second embodiment has a C
A modulated signal obtained by frequency-multiplexing the W signal is used as an input signal. The input signal input from the input port 9 is divided by the BFN2 into four signals having different phases and amplitudes, and the four output ports 10-1 to 10-4 are provided. Is output to However, the phase and amplitude at this time are based on the correction table data before the modulation signal obtained by frequency-multiplexing the CW signal is input.

The signals output from the output ports 10-1 to 10-4 are amplified by the corresponding amplifiers 3-1 to 3-4 as in the first embodiment, and then amplified by the antenna elements 7-1 to 4-1. Power is supplied to 7-4. At this time, a part of the signal fed to the antenna elements 7-1 to 7-4 is extracted by the directional couplers 4-1 to 4-4, and the terminals 17-1 to 17-1 are output.
The data is input to the corresponding BPFs 18-1 to 18-4 via 7-4.

From the power supply signals input to the BPFs 18-1 to 18-4, only the CW signals are extracted by the BPFs 18-1 to 18-4.
The signals are input to the phase / amplitude detection unit 5 via 3-1 to 13-4.

The phase and amplitude of the CW signal input to the phase and amplitude detector 5 are compared by the phase and amplitude detector 5 as in the first embodiment, and the resulting phase and amplitude comparison data is obtained. Is input to the beam control computer 6.

The beam control computer 6 first calculates the phase and amplitude of the CW signal extracted from each feed signal input to the antenna elements 7-1 to 7-4 from the comparison data, and then calculates The phase and amplitude of the obtained CW signal are compared with the values of the error table data. Here, when the error is smaller than the error range in the error table data, the following comparison is performed. On the other hand, if the error is larger than the error range in the error table data, the beam control computer 6 performs the following comparison after correcting the correction table data.

When the correction table data is corrected, the beam control computer 6 first calculates the corrected phase or amplitude based on the corrected correction table data and the control table data. Then, a modified control value required to realize the modified phase and amplitude is calculated, and the BFN 2 is controlled via the interface 8 based on the modified control value.

Therefore, the corrected phase and amplitude are applied to the input signal input after this correction. That is, similarly to the first embodiment, the BFN 2, the amplifiers 3-1 to 3-4, and the transmission path and the like connecting the amplifiers 3-1 to 3-4 with the antenna elements 7-1 to 7-4. The phase and amplitude fluctuations caused by the characteristic fluctuations occurring in any one of them are corrected, and the corrected feed signal is fed to each of the antenna elements 7-1 to 7-4. Can be corrected. Also, the directional couplers 4-1 to 4-1
Each of the amplifiers 3-1 to 3-
It goes without saying that correction can be made in consideration of the influence of the power supply signal on the transmission line connecting the antenna element 4 and each of the antenna elements 7-1 to 7-4. Further, by disposing the mounting positions of the directional couplers 4-1 to 4-4 in the vicinity of the antenna elements 7-1 to 7-4, it is possible to easily find a failure or the like occurring in the transmission path. The effect is obtained.

Furthermore, in the array antenna apparatus according to the second embodiment, since the correction operation for BFN2 can be performed during the period when the CW signal is multiplexed on the modulation signal, the CW signal is always multiplexed on the modulation signal. The beam control computer 6 constantly changes the phase and amplitude of the CW signal extracted from the feed signal fed to the antenna elements 7-1 to 7-4 extracted by the directional couplers 4-1 to 4-4. Since the monitoring can be performed, the correction according to the characteristic fluctuation can be performed in real time. However, the frequency and level of the CW signal multiplexed on the modulation signal are values that do not affect the modulation signal.

Since the correction operation for the BFN 2 is performed based on the phase and amplitude error data of the CW signal frequency-multiplexed with the modulation signal, the CW signal of the multiplex signal input from the terminal 1 and the modulation signal By setting the carrier frequency to a value as close as possible, the BFN 2 and the amplifiers 3-1 to 3-3 at the time of transmitting a desired modulated signal are transmitted.
For example, it is possible to minimize the correction error due to the frequency characteristic caused by -4 or the like.

(Embodiment 3) FIG. 5 is a view for explaining a schematic configuration of an array antenna apparatus according to Embodiment 3 of the present invention. However, the array antenna device according to the third embodiment is a receiving array antenna device, and an incoming signal in the following description is a signal in which a modulated signal is frequency-multiplexed with a CW signal.

As shown in FIG. 5, the array antenna apparatus according to the third embodiment has a low noise amplifier (hereinafter, referred to as "LNA") for amplifying incoming signals received by antenna elements 7-1 to 7-4, respectively. ) 19-1 to 19-4, and local oscillators (hereinafter, referred to as “LO”) of each system 2
0-1 to 20-4, multipliers 21-1 to 21-4, and four input signals input from input ports 22-1 to 22-4 are corrected in phase and amplitude, and then combined to form one signal. The other configuration except for the BFN 23 for obtaining an output is the same as that of the second embodiment. However, the BFN 23 in the third embodiment
Is, for example, four amplitude controls for controlling input signals after distribution in accordance with a control signal from the interface 8, that is, distribution signal amplitudes for input signals input from four input ports 22-1 to 22-4. And four IQ vector modulators as phase shifters for giving a time delay according to the control signal from the interface 8 to the signal whose amplitude has been adjusted and controlling the phase between the distribution signals. And well-known combining means for combining signals output from the four IQ vector modulators.

The incoming signals received by antenna elements 7-1 to 7-4 are first amplified by LNAs 19-1 to 19-4. Next, the amplified incoming signal is multiplied by a multiplier 2
According to 1-1 to 21-4, LO20-1 of each system is used.
20-4 to be converted into an intermediate frequency signal (hereinafter, referred to as an “IF signal”).
The data is output to the BFN 23 through -1 to 22-4.

Each IF signal input through the input ports 22-1 to 22-4 is converted by the BFN 23 into four I
The phase and amplitude of the F signal are corrected and then combined to form one signal, which is output to the output port 24 of the BFN 23 and output to the terminal 1 as a signal output. However, the phase and amplitude at this time are based on the correction table data before the input of the IF signal obtained by frequency-multiplexing the CW signal.

On the other hand, in the array antenna apparatus according to the third embodiment, directional couplers 4-1 to 4-4 are arranged in front of input ports 22-1 to 22-4. Therefore, a part of the IF signal output from the multipliers 21-1 to 21-4 is taken out by the directional couplers 4-1 to 4-4, and the band is passed through the terminals 17-1 to 17-4. The signals are input to pass filters (BPF) 18-1 to 18-4.

The I input to the BPFs 18-1 to 18-4
As for the F signal, only the CW signal is extracted by the BPFs 18-1 to 18-4.
The signals are input to the phase / amplitude detection unit 5 via 3-1 to 13-4.

The phase and amplitude of the CW signal input to the phase and amplitude detector 5 are compared by the phase and amplitude detector 5 as in the first embodiment, and the phase and amplitude comparison data obtained as a result is obtained. Is input to the beam control computer 6.

The beam controlling computer 6 first calculates the phase and amplitude of the CW signal extracted from each IF signal output from the multipliers 21-1 to 2104 from the comparison data, and then calculates the obtained CW signal. The phase and amplitude of the signal are compared with the values of the error table data. Here, when the error is smaller than the error range in the error table data, the following comparison is performed. On the other hand, if the error is larger than the error range in the error table data, the beam control computer 6 performs the following comparison after correcting the correction table data.

When the correction table data is corrected, the beam control computer 6 first calculates a corrected phase or amplitude based on the corrected correction table data and the control table data. Then, a corrected control value required to realize the corrected phase and amplitude is calculated, and the BFN 23 is controlled via the interface 8 based on the corrected control value.

Therefore, the corrected phase and amplitude are applied to the incoming signal input after this correction. That is, the relative positional relationship between the antenna elements 7-1 to 7-4, the antenna elements 7-1 to 7-4 and the LNA 1
Transmission lines connecting 9-1 to 19-4, each LNA 19-1 to
19-4 and a change in phase and amplitude caused by a characteristic change occurring in any one of the multipliers 21-1 to 21-4, etc., is corrected to obtain one output signal. Performance can be corrected with high accuracy.

Further, in the array antenna apparatus according to the third embodiment, the BFN
23, the CW is always added to the incoming signal.
By multiplexing the signals, monitoring can be performed at all times, and correction according to characteristic fluctuation can be performed in real time.

Further, a high frequency (RF) reception signal which is a signal arriving at each of the antenna elements 7-1 to 7-4 of the array antenna apparatus is down-converted into an IF signal (hereinafter referred to as "D /
C)), the LO used in D / C
20-1 to 20-4 are common, and the respective multipliers 21
For example, distribution of IF signals due to individual differences between the LOs 20-1 to 20-4 is suppressed by distributing the signals to -1 to 21-4 using an equal-length cable. For this reason, the conventional array antenna device not only has a complicated system configuration, but also has a large manufacturing cost.

On the other hand, the array antenna device according to the third embodiment has separate LOs 20-1 to 20-1 for each D / C.
Even when 20-4 is used, LO 20-1 to 20
-4, multipliers 21-1 to 21-4, and LNA 19-1
Since it is possible to acquire overall correction data including individual differences such as −４19-4, element characteristics, and characteristic fluctuations due to environmental changes such as temperature, etc., it is possible to simplify the system configuration and reduce the manufacturing cost. It is a thing. Further, since the number of components used can be reduced by facilitating the system configuration, the failure rate can be reduced, and the reliability of the system can be improved. Further, as described above, since the correction can be performed in real time, the reliability of the system can be further improved.

In the array antenna apparatus according to the third embodiment, a case has been described where the incoming signal is a signal obtained by frequency-multiplexing a CW signal on a modulated signal. However, the present invention is not limited to this. Needless to say, only the CW signal may be received, and the following modulation signal may be corrected based on the correction data in the reception period of the CW signal.

As described above, the invention made by the present inventor is:
Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the embodiments of the present invention, and it is needless to say that various modifications can be made without departing from the scope of the invention. .

[0079]

The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) Since a change in characteristics due to aging can be corrected, it is possible to prevent a decrease in the accuracy of the directivity of the combined beam over a long period of time. (2) Since characteristic changes due to environmental temperature and the like can be corrected,
The directional characteristics of the combined beam can be stabilized.

(3) Since the directional characteristics of the combined beam can be stabilized, the reliability of the array antenna device can be improved. (4) Since it is not necessary to perform measurement using the radio wave anechoic chamber for adjusting the BFN and the amplifier, the labor and time involved in changing the correction value can be reduced. That is, the maintainability of the array antenna device can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a schematic configuration of an array antenna device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a schematic configuration of a BFN according to the first embodiment.

FIG. 3 is a diagram for explaining a schematic configuration of a phase and amplitude detector according to the first embodiment;

FIG. 4 is a diagram for explaining a schematic configuration of an array antenna device according to a second embodiment of the present invention.

FIG. 5 is a diagram for explaining a schematic configuration of an array antenna device according to a third embodiment of the present invention.

[Explanation of symbols]

1, 16 terminal 2 beamforming network 3-1 to 3-4 amplifier 4-1 to 4-4
Directional coupler 5 ... Phase and amplitude detector 6 ... Computer for beam control 7-1 to 7-4 ... Antenna element 8 ... Interface 9 ... Input port 10-1 to 10-
4 Output port 11-1 to 11-4 IQ vector modulator 12-1 to 12-4 Amplitude controller 13-1 to 13-
4 Terminal 14 Switch 15 Network analyzer 17-1 to 17-4 Terminal 18-1 to 18-4 Bandpass filter 19-1 to 19-4 Low noise amplifier 20-1 to 20-4 Local oscillator 21-1 to 21-4 Multipliers 22-1 to 22-4 ... Input Ports 23 ... Beamforming Network 24 ... Output Ports

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hitoshi Nakagawa 1-10-11 Kinuta, Setagaya-ku, Tokyo Inside Japan Broadcasting Corporation Broadcasting Research Institute (72) Inventor Takao Murata 1-10-11 Kinuta, Setagaya-ku, Tokyo No. Japan Broadcasting Corporation Broadcasting Research Institute F term (reference) 5J021 AA04 AA06 CA06 DB02 DB03 EA04 FA14 FA15 FA16 FA17 FA20 FA26 FA29 FA30 FA32 GA02 HA05 HA10

Claims (3)

[Claims] 1. A beam forming means for dividing an input signal into two or more signals and giving a predetermined phase shift and amplitude to the divided signal, and an amplifying means for amplifying a signal output from the beam forming means. And a plurality of antenna elements that output a beam of a signal fed from the amplifying means, and an array antenna apparatus that forms a combined beam having directivity according to the phase shift amount and the amplitude. Extraction means for respectively extracting a signal to be fed, and monitoring a phase shift amount and an amplitude of the signal fed to the antenna element, and when the phase shift amount and the amplitude exceed a preset range, the beam Phase-amplitude control means for controlling the shaping means and adjusting the phase shift and amplitude applied to the distributed signal. Tena device. 2. The array antenna device according to claim 1, wherein said beam forming means changes an amplitude of said distributed input signal according to a control output of said control means, and said control means. And a phase shifter that varies a phase shift amount of the divided input signal in accordance with the control output of the array antenna. 3. The array antenna device according to claim 1, wherein the control unit sets any one of the plurality of signals extracted by the extraction unit as a reference signal and the reference signal and another signal. And means for comparing the phase shift amount and the amplitude of the beam forming means with each other, and controlling the phase shift amount and / or the amplitude of the beam forming means based on the comparison result.