JP4012520B2 - Array antenna communication apparatus and control method - Google Patents

Description

  The present invention relates to a communication apparatus that controls a transmission / reception antenna pattern using a plurality of antennas, and more particularly to an adaptive array antenna control apparatus and control method.

  Reception with a beam in the direction of arrival of the desired wave and a null in the direction of arrival of the interference wave by appropriately adding and synthesizing the signals received by a plurality of unit antennas arranged spatially separated from each other A communication apparatus having an adaptive array antenna that forms an antenna pattern and selectively receives a desired signal is known.

  FIG. 6 is a block diagram showing an overall configuration of a conventional adaptive array communication apparatus. In a conventional adaptive array antenna, in order to obtain a desired transmission / reception antenna pattern, an appropriate weighting process is applied to the amplitude and phase of the transmission / reception signal. However, in such a control, in a receiving circuit corresponding to each antenna element, a temporal variation occurs due to aging deterioration of the analog elements of the coupler, the distributor, and the amplifier.

  For this reason, a difference in phase and amplitude between the received signal (RX) and the monitor signal (monitor RX) or a delay difference occurs due to variations in phase and amplitude characteristics, and unknown amplitude fluctuations and phase rotations are added. Therefore, the directivity pattern is formed differently from what is desired. Such a characteristic difference or delay difference between the respective receiving circuits causes a decrease in reception gain, leading to deterioration in communication quality.

  Therefore, as shown in Patent Document 1, in order to detect the amplitude characteristic and delay characteristic of the wireless receiver, a signal having the same bandwidth as that of the spread signal used in actual spread spectrum communication or a signal having a band close thereto is used. An accurate amplitude characteristic and delay difference are detected by comparing the correlation output obtained by despreading the output signal from each radio reception unit with the reference identification point, as a calibration signal.

  In addition, a technique as disclosed in Patent Document 2 is disclosed, and the adaptive array antenna receiving apparatus calculates the characteristics of the phase and amplitude of each receiving circuit to obtain a calibration coefficient, and calculates the received communication signal. A characteristic difference between the receiving circuits is compensated by multiplying the phase component and amplitude component of the calculated calibration coefficient by the phase component and amplitude component, respectively.

  Furthermore, the applicant of the present application has applied for an improved array antenna communication apparatus as Japanese Patent Application No. 2003-151825. According to the prior application invention, with respect to the RF transmission system circuit and the RF reception system circuit corresponding to the four system unit antennas, the difference between the amplitude variation amounts and the difference between the phase rotation amounts when the signals pass through them are each unit. It is almost equal between the antennas, and is directly or frequency converted into a signal output from the RF receiving system circuit.

  After that, the code signals orthogonalized with each other are multiplied for each unit antenna, then multiplexed, input to the monitor receiver, and the output of the monitor receiver is multiplied again with the code signal corresponding to each unit antenna. Thus, an application is being filed in which a circuit configuration is simplified by reproducing a signal corresponding to each antenna and inputting the signal to an adaptive array control unit.

JP-A-11-46180 Japanese Patent Laid-Open No. 2002-300086 "Adaptive signal processing by array antenna", first edition, Science and Technology Publishing Co., Ltd., November 1998

  Conventionally, in order to reduce the circuit scale of the monitor receiver used in the control of the adaptive array antenna, in the conventional method, the united antenna monitor signal is multiplexed after being multiplied by the code signal orthogonalized for each unit antenna. There is a technology that can be realized by one monitor receiver by sharing a common receiver. This technique simplifies the circuit configuration and reduces the error in the delay amount between the signals.

  In order to reproduce the signal corresponding to each unit antenna again by multiplying the output of the receiver by the code corresponding to each unit antenna, the timing of the code signal to be multiplied is matched with the code signal included in the monitor reception signal. Multiplication is required, that is, synchronization with the code signal is required. Therefore, it is necessary to optimize the delay amount of the delay circuit so that the timing shift or the synchronization shift is minimized.

  However, the optimal amount of delay is determined by the electrical characteristics of the signal path that passes after the orthogonalized code is multiplied, but if the characteristics change due to temperature or aging, the delay amount set in the delay circuit If is not optimal, there is a problem that synchronization cannot be maintained and the monitor reception signal corresponding to each unit antenna cannot be reproduced.

  In addition, in a system such as a mobile base station that performs time-division communication, a reference signal is newly injected to detect synchronization points even when trying to establish synchronization using idle time when communication is not performed. Therefore, there is a problem that it is necessary to provide a means for performing such a process, which increases the manufacturing cost.

  In view of the above-described conventional problems, the present invention adjusts the amount of delay in a system such as a mobile communication base station that performs time-division communication by using a free time during which communication is not performed even without a reference signal injection unit. It is another object of the present invention to provide an improved array antenna communication apparatus capable of maintaining synchronization.

  In order to solve the above problems, an array antenna communication apparatus according to the present invention includes a transmission / reception system using an adaptive array antenna including a plurality of unit antennas, and a monitor system for monitoring the directivity of each unit antenna. , And an array antenna communication apparatus.

  The transmission / reception system includes an RF transmission amplification unit provided for each unit antenna, an RF reception amplification unit provided in parallel with the RF transmission amplification unit for each unit antenna, and the RF transmission amplification unit or the RF reception amplification. A weighting unit that is connected by switching, a distribution unit that is connected to a plurality of weighting units, distributes transmission signals, and synthesizes reception signals, and a transmission unit (TX) and reception unit that are connected to the distribution combination unit (RX) and an adaptive array control unit that controls the weighting unit to cause the plurality of unit antennas to function as an adaptive array antenna.

  The monitor system includes a spread multiplexing unit that spreads and multiplexes signals for each unit antenna branched from the RF reception amplification unit, and a monitor reception unit (monitor RX) that performs frequency conversion and amplification of the spread multiplexed signals. And a despreading / separating unit that despreads and separates the signal from the monitor receiving unit with a spreading code for each unit antenna, and the timing of the spread code supplied to the spreading and multiplexing unit is corrected by the delay amount of the monitor receiving unit. A synchronization tracking unit that supplies a spreading code to the despreading separation unit.

  The synchronization tracking unit includes a spreading code output unit that outputs a spreading code, a code delay unit that delays the spreading code, a level detection unit that detects at least amplitude or power of the despreading separation unit, and a communication status And a delay control unit that acquires a detection result from the level detection unit and sets a corrected delay amount to the code delay unit, and uses the detected level as an evaluation index, and a monitor. It is characterized in that synchronization tracking is performed by obtaining and correcting a delay amount using a received signal and setting the corrected delay amount in the code delay unit.

  Further, in the array antenna communication apparatus according to the present invention, the delay control unit acquires a detection result from the empty slot information and the level detection unit, measures a delay amount, and determines the delay unit according to a sampling interval of the monitor reception signal. A delay amount variable means for varying the delay amount, a delay amount storage means for storing a delay amount by the delay amount variable means and a detection result of the level detector, and a delay amount using the detected level as an evaluation index A delay amount determining means for determining a delay amount close to a synchronization point from the delay amount, and setting the corrected delay amount in the code delay unit to establish synchronization. It is characterized by.

  Furthermore, the array antenna communication apparatus according to the present invention is characterized in that the evaluation index is the maximum or minimum of at least one of amplitude, power, and noise.

  Furthermore, in the array antenna communication apparatus according to the present invention, the spreading code output unit has storage means for storing the spreading code, is orthogonal to each other at the synchronization point, has no DC component, and is multiplied by the received signal. In this case, a code signal in which the frequency bands are equal and the synchronization point can be determined by the correlation value in the vicinity of the synchronization point is stored and output.

  Furthermore, in the array antenna communication apparatus of the present invention, the spreading code output unit further has a small number of consecutive “0” s for sequences generated by in-phase addition, and for sequences generated by in-phase addition. A code signal with a small number of 0 'is stored and output.

  Furthermore, the base station or the mobile station using the array antenna communication apparatus according to the present invention is characterized by detecting an empty slot in which communication is not performed and tracking the synchronization of the adaptive array antenna.

  An array antenna communication apparatus control method according to the present invention includes a transmission / reception process using an adaptive array antenna including a plurality of unit antennas, and a monitor process for monitoring the directivity of the unit antennas. Regarding the method.

  The transmission / reception process includes an RF transmission amplification process and an RF reception amplification process provided for each unit antenna, a weighting process for weighting the signals of the RF transmission amplification process and the RF reception amplification process, and the weighting process. A distribution and synthesis step for distributing and synthesizing the obtained signals, a transmission step (TX) for transmitting the signal of the distribution and synthesis step, a reception step (RX) for receiving the signal, and controlling the weighting step to control a plurality of unit antennas. And an adaptive array control step for functioning as an adaptive array antenna.

  The monitoring step includes a diffusion multiplexing step for spreading and multiplexing the signal for each unit antenna branched from the RF reception amplification step, and a monitor reception step (monitor RX) for frequency-converting and amplifying the spread multiplexed signal. And despreading and despreading the signal from the monitor receiving step with a spreading code for each unit antenna, and correcting the timing of the spread code supplied to the spreading and multiplexing step with the delay amount of the monitor receiving step. A synchronization tracking step of supplying a spreading code to the despreading separation step.

  The synchronization tracking step includes a spreading code output step for outputting a spreading code, a code delay step for delaying the spreading code, a level detection step for detecting at least amplitude or power of the despreading separation step, and a communication status A delay control step for obtaining a detection result from the empty slot information indicating the level and a level detection step and setting a corrected delay amount to the code delay step, and using the magnitude of the detected level as an evaluation index, and a monitor The received signal is used to determine and correct the delay amount, and based on the corrected delay amount, the corresponding spreading code is monitored in order to correctly separate the desired signal from the signal spread and multiplexed by the spreading code. It is characterized in that it is output in synchronization with the signal of the spread code included in the received signal.

  In the present invention, the spread code synchronization is traced by using the other station signal input from the antenna in the idle time when the own station does not communicate. The received signal used to perform synchronization tracking does not necessarily have to be for the local station, but signals for other stations do not always exist. When a signal having a quality sufficient to secure the signal is received, synchronization is tracked using the received signal.

  To determine the synchronization point, the spreading code is used as it is, and the setting of the delay amount is changed based on the amplitude level (correlation value) of the integrator output for the current delay amount and the delay amount before and after that. Move closer to the amount of delay.

  By performing these operations repeatedly using the idle time of the communication before the delay amount greatly changes due to the change in the electrical characteristics of the monitor reception signal path, the reference circuit injection means can be used without the reference signal injection means. An optimum delay amount can be maintained.

  The array antenna communication apparatus using the present invention uses the signal of the other station in the idle time when the local station does not communicate in the time division communication system, so that the optimum delay circuit can be used without the reference signal injection means for the correlation value. This makes it possible to maintain a large amount of delay.

1 Device Configuration FIG. 1 is a block diagram showing a main part of an array antenna communication device according to the present embodiment. A description will be given based on the drawings showing an example of four antennas.

  The adaptive array antenna includes four unit antennas 1, and a signal input to each antenna 1 passes through a low noise amplifier 3 (LNA) with a transmission / reception switch connected to the reception side, Input to the weighting circuit 5. Here, between the transmission / reception switch 4, the transmission system and the reception system have separate and independent circuits (that is, the RF transmission system circuit and the RF reception system circuit), and the RF transmission system circuit includes transmission power. An amplifier 2 (PA) is provided in parallel.

  The received signals are weighted with respect to the amplitude and phase in the weighting circuit 5, and the signals of the unit antennas 1 are combined in the distribution / combination unit and supplied to the baseband processing unit 9 through the receiver 8.

  On the other hand, the transmission signal is sent from the baseband processing unit 9 to the distribution / combination unit 6 from the transmission / reception switch 4 via the transmitter 7. In order to control the weighting by the weighting circuit 5 to an optimum value, an adaptive array control unit 10 is provided. The adaptive array control unit 10 includes a reception signal from the receiver 8 described above and a monitor receiver 14 described later. Is supplied to a weighting circuit for each unit antenna 1, and a desired weighting value obtained thereby is supplied to the weighting circuit for each unit antenna 1.

  About the RF transmission system circuit and the RF reception system circuit corresponding to each unit antenna 1, the difference in amplitude change amount and the difference in phase rotation amount when signals pass through them are substantially equal between the unit antennas 1, Directly or frequency-converted into a signal output from the RF receiving system circuit.

  Thereafter, the code signals (orthogonal codes) orthogonalized to each unit antenna 1 are multiplied and spread-multiplexed and input to the monitor receiver 14, and the output of the monitor receiver 14 corresponds to each unit antenna 1. The resultant code signals are multiplied again and integrated to perform despreading separation, and a signal corresponding to each unit antenna 1 is regenerated and input to the adaptive array control unit 10.

  The delay control device 22 obtains a signal indicating whether the current communication is an empty slot from a higher-level communication control device. The delay circuit 17 changes the delay amount according to the control signal from the delay control device 22.

  In order to correctly separate the signal for each unit antenna 1 from the signal spread and multiplexed by the orthogonal code, the timing of the code signal to be multiplied for despreading separation is matched with the code signal included in the monitor reception signal. Need to multiply. Therefore, the delay control device 22 optimizes the delay amount so that the timing deviation is minimized.

  The amplitude detector 23 detects the magnitude of the amplitude of the received signal, which is the output of the integrator, and transmits it to the delay control device 22. The delay control device 22 controls the set value switching, determines the presence / absence of a received signal that can be used for measurement by using the amplitude level output from the amplitude detector 23 as an evaluation value, obtains an optimum delay amount, The delay amount setting value of the circuit 17 is updated.

2. Correlation characteristics of orthogonal code Some conditions required for the optimal orthogonal code when selecting an orthogonal code are shown below.
(1) orthogonal to each other at the synchronization point (2) no DC component (3) frequency bandwidth when multiplied by the received signal is as equal as possible (4) correlation value (including cross-correlation) around the synchronization point The synchronization point can be determined. (5) The number of consecutive 0s is small for a sequence generated by in-phase addition of four codes. (6) The number of zeros is small for a sequence generated by in-phase addition of four codes.

図２は、本発明の実施形態に係る直交用符号の相関特性を示す特性図である。この図は、表１の候補リストの組み合わせで得られる相関特性の理論値である。これらの符号を用いると同期点で自己相関が最大となり、同期点からのズレが１／２チップ以内である場合は、相互相関の絶対値和より自己相関の絶対値和の方が高いが、その領域を超えると、自己相関よりも相互相関の絶対値和の方が大きくなるので相関値に基づいて遅延量を制御することが出来なくなる。 When the code length is n according to system requirements, there are 2n candidates that can be codes, and a code that satisfies the above conditions 1 to 6 is obtained using a computer. Table 1 shows candidates obtained by selecting an optimal spreading code when n = 8. (Table 1) is a candidate list of orthogonal codes, and patterns “0” and “1” are selected in the table. However, when actually performing the correlation calculation, it goes without saying that “0” is replaced with “−1” and multiplication is performed.

FIG. 2 is a characteristic diagram showing the correlation characteristics of the orthogonal code according to the embodiment of the present invention. This figure is a theoretical value of correlation characteristics obtained by the combination of candidate lists in Table 1. When these codes are used, the autocorrelation is maximized at the synchronization point, and when the deviation from the synchronization point is within 1/2 chip, the absolute value sum of the autocorrelation is higher than the absolute value sum of the cross correlations. Beyond that region, the sum of absolute values of the cross-correlation becomes larger than the autocorrelation, so that the delay amount cannot be controlled based on the correlation value.

  FIG. 3 shows experimental results obtained by actually performing measurement using the adaptive array communication apparatus according to the embodiment of the present invention. This figure shows the correlation characteristics obtained by experimenting with the prototype device.

  From the result shown in FIG. 3, since the cross-correlation is close to “0” near the synchronization point, it is possible to determine the synchronization point based on the magnitude of the correlation characteristic (output level of the amplitude detector). If the deviation from the point exceeds 1/2, the magnitude of the cross-correlation is the same as or greater than the magnitude of the autocorrelation, so that the synchronization point discrimination success based on the magnitude of the correlation characteristic cannot be guaranteed.

  Further, when the deviation increases to the place where the cross-correlation peak appears, the correlation value peak becomes the same level as the peak at the synchronization point, and the synchronization point cannot be determined by the correlation characteristics.

  Therefore, in order to correct the delay amount and maintain the synchronization, it is necessary to repeatedly correct the delay amount before the deviation from the synchronization point becomes 1/2 chip or more.

3 Specific Method of Synchronization Tracking FIG. 4 is a flowchart showing the flow of the synchronization tracking processing according to the embodiment of the present invention. A procedure for performing synchronization tracking will be described with reference to a flowchart.

  First, code synchronization is established by some method, and then the characteristics of the monitor receiver change and the optimum value of the delay amount changes.At present, the delay amount is out of the synchronization point, but cannot be pulled in. Assume that it is not so different. Further, it is assumed that synchronization tracking is repeated at such a frequency that the assumption holds.

  When code synchronization tracking is started from step S11, the communication state is confirmed, and the amplitude level is monitored by the amplitude detector 23.

Procedure 1 Monitor received signal amplitude value After the communication of the local station is interrupted and the operation of the adaptive array antenna is suspended, the amplitude detector determines whether there is another station signal that can be used for synchronous tracking measurement. Monitor with reference to 23 outputs. (Step S12)

Procedure 2 Controlling the Delay Amount of the Delay Circuit In this embodiment, the delay circuit 17 is composed of a digital circuit, so that the delay amount can be controlled with the resolution of the sample interval of the received signal. The delay amount of the delay circuit 17 is changed within the range of the current delay amount setting value and the delay amount setting value of ± 1 sample before and after that. In preparation for the case where the reception state during measurement is bad and the measurement result becomes invalid, the measurement with the current delay amount is performed last. After the measurement, the delay amount setting value becomes the same value as before the measurement. (Step S13) The reason why the variable range of the delay setting amount is set to ± 1 is the result of placing importance on the certainty of the synchronization point determination rather than the speed of the tracking speed. The range may be expanded to ± 1 or more.

Procedure 3 Recording the magnitude of the correlation value The amplitude detector 23 measures the magnitude of the amplitude level of the received signal. Similar to the correlation characteristics shown in FIG. 2, the place with the highest correlation value is the synchronization point. The received signal amplitude value (correlation value) is recorded as a pair with the delay amount setting value in order to compare the magnitudes after all measurements are completed. (Step S14)

  Steps 2 and 3 are repeated until the measurement for all the set values is completed. (Step S15)

Procedure 4 Determination of whether or not to adopt the measurement result Next, if the received signal amplitude value that has been monitored during measurement exceeds the threshold value, the delay amount that maximizes the amplitude value is selected. The value of the delay amount setting value is updated (step S17).

  If the received signal amplitude value is less than or equal to the threshold value, it is determined that the reliability of the measurement result is low and invalid (step S18).

  By repeating the above operation, the delay amount is corrected so as to approach the synchronization point even if the operation is out of the synchronization point, and eventually stabilizes at the synchronization point.

  Even if there is no reference signal injection means, the delay circuit is executed by repeatedly executing such processing before the delay amount largely changes due to the change in the electrical characteristics of the monitor reception signal path by utilizing the communication idle time. It is possible to maintain the optimum delay amount.

  In the present embodiment, the amplitude value from the amplitude detector 23 is used. However, the amplitude detector 23 may be a power detector, and noise detecting means for detecting noise inside the integrator 11 is used. For example, an impulsive noise may be detected, or the communication quality may be measured preferably by detecting an error rate or the like.

  In this embodiment, an orthogonal code having the property that four codes are orthogonal to each other is used as a code signal (spreading code) for performing spreading multiplexing and despreading separation. A combination of code signals that are sufficiently small so as not to occur (for example, a pseudo-noise code such as an M-sequence) may be used.

It is a block diagram which shows the structure of the array antenna communication apparatus which concerns on 1st Embodiment. It is a characteristic view which shows the correlation characteristic of the code for orthogonality which concerns on embodiment of this invention. It is the experimental result obtained by actually measuring using the adaptive array communication apparatus which concerns on embodiment of this invention. It is a flowchart which shows the flow of a process of the synchronous tracking which concerns on embodiment of this invention. It is a block diagram which shows the structure of the conventional adaptive array communication apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Antenna, 2 Transmission power amplifier, 3 Low noise amplifier, 4 Transmission / reception switch, 5 Weighting circuit, 6 Distribution combining part, 7 Transmitter, 8 Receiver, 9 Baseband processing part, 10 Adaptive array control part, 11 Integrator 12, 16 multipliers, 14 monitor receivers, 17 delay circuits, 22 delay control devices, 23 amplitude detectors.

Claims (7)

In an array antenna communication apparatus having a transmission / reception system using an adaptive array antenna including a plurality of unit antennas, and a monitor system for monitoring the directivity of each unit antenna,
The transmission / reception system is:
An RF transmission amplification unit provided for each unit antenna;
An RF reception amplification unit provided in parallel with the RF transmission amplification unit for each unit antenna;
A weighting unit that is switched and connected to the RF transmission amplification unit or the RF reception amplification unit;
A distribution combining unit that is connected to a plurality of weighting units, distributes transmission signals, and combines reception signals;
A transmission unit (TX) and a reception unit (RX) connected to the distribution and synthesis unit;
An adaptive array control unit that controls the weighting unit to cause a plurality of unit antennas to function as an adaptive array antenna;
With
The monitor system is
A spreading multiplex unit for spreading and multiplexing signals per unit antenna branched from the RF reception amplification unit;
A monitor receiver (monitor RX) for frequency-converting and amplifying the spread-multiplexed signal;
A despreading and separating unit for despreading and separating the signal from the monitor receiving unit with a spreading code for each unit antenna;
A synchronization tracking unit that corrects the timing of the spread code supplied to the spread multiplexing unit with the delay amount of the monitor receiving unit and supplies the spread code to the despreading separation unit;
With
The synchronous tracking unit
A spreading code output unit for outputting a spreading code;
A code delay unit that delays the spreading code;
A level detection unit for detecting at least amplitude or power of the despreading separation unit;
A delay control unit that obtains a detection result from empty slot information indicating a communication status and a level detection unit, and sets a corrected delay amount in the code delay unit;
With
An array characterized in that the magnitude of the detected level is used as an evaluation index, a delay amount is obtained and corrected using a monitor reception signal, and synchronization tracking is performed by setting the corrected delay amount in the code delay unit. Antenna communication device. The array antenna communication apparatus according to claim 1,
The delay control unit
A delay amount varying means for obtaining a detection result from the empty slot information and the level detection unit, measuring a delay amount, and varying the delay amount of the delay unit in units of sample intervals of the monitor reception signal;
Delay amount storage means for storing the delay amount by the delay amount variable means and the detection result of the level detector;
Using the magnitude of the detected level as an evaluation index, a delay amount is searched from the delay amount storage unit, and a delay amount determination unit that determines a delay amount close to the synchronization point from the delay amount;
With
An array antenna communication apparatus, wherein synchronization is established by setting a corrected delay amount in the code delay unit. The array antenna communication apparatus according to claim 1 or 2,
The array antenna communication apparatus, wherein the evaluation index is a maximum or minimum of at least one of amplitude, power, and noise. The array antenna communication apparatus according to any one of claims 1 to 3,
The spreading code output unit includes:
Having storage means for storing the spreading code;
Store and output a code signal that is orthogonal to each other at the synchronization point, has no DC component, has the same frequency band when multiplied by the received signal, and can identify the synchronization point by the correlation value near the synchronization point An array antenna communication device. The array antenna communication apparatus according to claim 4, wherein
The spreading code output unit further includes:
An array antenna characterized by storing and outputting a code signal having a small number of consecutive “0” s for a sequence generated by in-phase addition and a small number of “0” s for a sequence generated by in-phase addition. Communication device. In a base station or mobile station using the array antenna communication apparatus according to any one of claims 1 to 5,
A base station or mobile station using an array antenna communication apparatus, wherein an idle slot in which communication is not performed is detected and synchronization of an adaptive array antenna is tracked. In a method for controlling an array antenna communication apparatus, comprising: a transmission / reception process using an adaptive array antenna including a plurality of unit antennas; and a monitoring process for monitoring the directivity of the unit antennas.
The transmitting / receiving step includes
RF transmission amplification step and RF reception amplification step provided for each unit antenna;
A weighting step for weighting signals of the RF transmission amplification step and the RF reception amplification step;
A distribution and synthesis step for distributing and synthesizing the signals obtained in the weighting step;
A transmission step (TX) for transmitting a signal of the distribution and synthesis step, and a reception step (RX) for receiving the signal;
An adaptive array control step of controlling the weighting step so that a plurality of unit antennas function as an adaptive array antenna;
With
The monitoring step includes
A spreading and multiplexing step for spreading and multiplexing signals per unit antenna branched from the RF reception and amplification step;
A monitor reception step (monitor RX) for frequency-converting and amplifying the spread multiplexed signal;
A despreading separation step of despreading the signal from the monitor reception step with a spreading code for each unit antenna;
A synchronization tracking step of correcting the timing of the spread code supplied to the spread multiplex step with the delay amount of the monitor reception step and supplying the spread code to the despread separation step;
With
The synchronous tracking process includes
A spreading code output step for outputting a spreading code;
A code delaying step for delaying the spreading code;
A level detection step of detecting at least amplitude or power of the despreading separation step;
A delay control step of acquiring a detection result from empty slot information indicating a communication status and a level detection step, and setting a corrected delay amount to the code delay step;
With
Using the magnitude of the detected level as an evaluation index, the monitor reception signal is used to determine and correct the delay amount. Based on the corrected delay amount, the desired signal is correctly obtained from the signal spread and multiplexed by the spreading code. A method of controlling an array antenna communication apparatus, wherein a corresponding spreading code is output in synchronization with a spreading code signal included in a monitor reception signal.

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