JP2006174333A - Array antenna transmitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable calibration of an array antenna transmitter provided with several antennas without increasing the circuit scale. <P>SOLUTION: The array antenna transmitter is provided with transmission wireless circuits 16 corresponding to several antennas 0, 1 and 2, a calibration signal generation circuit 23 which generates calibration signals, a calibration addition circuit 14 which adds the calibration signals to transmission signals in a different time-position, a multiplexing circuit 18 which branches a part of output signals of the transmission wireless circuits 16 and multiplexes it, a reception wireless circuit 19 which receives the multiplexed signals and demodulates them, a calibration signal extraction circuit 24 which extracts calibration signals corresponding to the antennas from the demodulated output signals, a phase error detection circuit 25 which figures out a phase rotation amount of a transmission path including the transmission wireless circuits 16 according to the extracted calibration signals and a phase compensation circuit 13 which compensates the phase by multiplying the transmission signals to be inputted to the transmission wireless circuits 16 according to the phase rotation amount. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an array antenna transmission apparatus configured with a plurality of antennas and capable of controlling transmission directivity.

  An array antenna transmission apparatus including a plurality of antennas can set transmission directivity by controlling the phase and amplitude of a transmission signal corresponding to the antenna. By setting the transmission directivity in the direction from the station to the mobile station, efficient communication is possible. Even if the phase and amplitude of the transmission signal in that case are controlled for the antenna in the baseband processing unit in the previous stage of the wireless transmission unit, the characteristics in the actual wireless transmission unit are the same for the antenna The characteristics may change due to aging.

  Therefore, array antenna calibration means for demodulating a signal input to the antenna and determining whether the signal phase and amplitude set to obtain the transmission directivity in the desired direction are set correctly has also been proposed. . The means for setting the phase and amplitude of the transmission signal will also differ according to the radio communication system such as the modulation system and the multiplexing system, but for example, it is applied to a CDMA (Code Division Multiple Access) system, In addition, an array antenna transmission apparatus to which array antenna calibration means is applied has been proposed (see, for example, Patent Document 1).

This array antenna transmission apparatus inputs a calibration signal having the same bandwidth as a spread signal used for communication to a transmission radio circuit, adds a transmission signal input from the transmission radio circuit to the antenna by an adding means, and receives radio By inputting to the circuit, separating for each transmission radio circuit and demodulating each, the phase characteristic variation of each transmission radio circuit is obtained, and the transmission signal is multiplied by the inverse characteristic value for correcting the variation, thereby transmitting radio circuit It has the structure which inputs to. Therefore, since the calibration signal is simultaneously input to the antenna-compatible transmission radio circuit, a different spread code is used for the spreading code of each calibration signal, and the antenna-compatible transmission signal is received wirelessly. Since the signal input to the circuit is demodulated simultaneously with the transmission signal corresponding to the antenna, the demodulation circuit is provided for the wireless transmission circuit.
Japanese Patent Laid-Open No. 10-336149

As described above, the array antenna transmission apparatus performs a process of correcting an error by inputting a calibration signal and obtaining an error in order to correct a variation in characteristics of circuit elements corresponding to the antenna. However, the conventional example to which the above-described CDMA system is applied has the following problems. That is,
(1). A calibration signal is generated by multiplying each transmission information symbol signal corresponding to each antenna by a different spreading code, input to the transmission radio circuit corresponding to the antenna, and the amount of phase rotation in each transmission radio circuit is obtained. Since demodulation circuits are required as many as the number of transmission radio circuits, there is a problem that the circuit scale as an array antenna transmission apparatus increases. Also, since the number of spreading codes is finite, if a large number of spreading codes are used for calibration, the number of spreading codes that can be used to spread and transmit the user's transmission signal is reduced, so that it can be accommodated in the system. There is a problem that the number of users decreases.

  (2). Since the control is not performed so that the ratio SIR (Signal to Interference Ratio) between the calibration signal level (S) and the transmission signal level (I) is constant, the transmission signal level is set to the calibration signal level. If it is large, there is a problem that the accuracy of calibration deteriorates. If the transmission signal level is smaller than the calibration signal level, the calibration signal interferes with the transmission signal, which causes a problem of deterioration in communication quality.

  The present invention solves the above-described problems of the conventional example, and an object of the present invention is to enable calibration of an array antenna without increasing the circuit scale.

  An array antenna transmission apparatus according to the present invention has a transmission radio circuit corresponding to a plurality of antennas, and a calibration signal for generating a calibration signal in the array antenna transmission apparatus capable of controlling transmission directivity by the plurality of antennas. A signal generation circuit, a calibration addition circuit that adds a calibration signal from the calibration signal generation circuit to a transmission signal input to a plurality of antenna-compatible transmission radio circuits at different time positions, and a transmission radio circuit A multiplexing circuit that divides and multiplexes the output signal, a receiving radio circuit that inputs and demodulates the signal multiplexed by the multiplexing circuit, and a calibration signal corresponding to the antenna from the demodulated output signal of the receiving radio circuit Calibration signal extraction circuit for extracting the Based on the calibration signal for the antenna extracted by the extraction circuit, the phase error detection circuit that calculates the phase rotation amount of the transmission path including the transmission radio circuit, and the phase rotation amount calculated by this phase error detection circuit A phase correction circuit that multiplies the transmission signal input to the wireless circuit to correct the phase.

  Also, a delay circuit that delays the calibration signal from the calibration signal generation circuit so as to have different delay times with respect to the transmission signal input to the antenna-compatible transmission radio circuit, and inputs the delay signal to the calibration signal addition circuit. Can be provided.

  Also, a transmission level monitoring circuit for monitoring the transmission level of the transmission signal input to the antenna-compatible transmission radio circuit, and a spreading code length corresponding to the transmission level by the transmission level monitoring circuit are obtained, and the calibration signal generation circuit is known. And a spreading length calculation circuit for controlling a spreading code for spreading and encoding the transmission information symbol.

  Also, a transmission level monitoring circuit that monitors the transmission level of the transmission signal input to the antenna-compatible transmission radio circuit, and an amplitude value calculation that controls the amplitude value of the calibration signal corresponding to the transmission level by the transmission level monitoring circuit A circuit.

  Also, the calibration error that monitors the phase error of the transmitting radio circuit corresponding to the antenna, detects that the condition for increasing the phase error has been set in advance, activates the calibration signal generation circuit, and executes the calibration process. A monitoring unit can be provided.

  By adding the calibration signal to the transmission signal input to the antenna-compatible transmission radio circuit so that the time positions are different from each other, the output signal of the transmission radio circuit is partially branched and multiplexed and input to the reception radio circuit Then, since the calibration signals corresponding to the antennas are time-multiplexed, only one calibration signal demodulation circuit is required, and there is an advantage that the cost is not increased even if the number of antennas is increased. . Further, by detecting the level of the transmission signal, the amplitude or spreading code length of the calibration signal can be controlled so that the SIR between the calibration signal and the transmission signal is constant, so that the calibration accuracy can be maintained. is there. Therefore, the problems (1) and (2) of the conventional example described above can be solved.

  The array antenna transmission apparatus according to the present invention will be described with reference to FIG. 1. The transmission antenna circuit 16 corresponds to a plurality of antennas 0, 1, 2 and controls the transmission directivity by the plurality of antennas 0, 1, 2. An array antenna transmission apparatus that enables calibration signal generation circuit 23 that generates a calibration signal, and transmits calibration signals from calibration signal generation circuit 23 corresponding to a plurality of antennas 0, 1, and 2. Calibration addition circuit 14 for adding the transmission signal input to radio circuit 16 at different time positions, multiplexing circuit 18 for branching and multiplexing the output signal of transmission radio circuit 16, and multiplexing by this multiplexing circuit 18 Receiving radio circuit 19 that receives the demodulated signal and demodulates it, and from the demodulated output signal of this receiving radio circuit 19, antennas 0, , 2, a calibration signal extraction circuit 24 for extracting calibration signals corresponding to 2, and a phase rotation amount of a transmission path including the transmission radio circuit 16 based on the calibration signal for antennas extracted by the calibration signal extraction circuit 24 And a phase correction circuit 13 that multiplies the transmission signal input to the transmission radio circuit 16 to correct the phase based on the phase rotation amount obtained by the phase error detection circuit 25. .

  FIG. 1 is an explanatory diagram of Embodiment 1 of the present invention, showing the main part of an array antenna transmission apparatus having three antennas, where 0, 1, 2 are antennas, 10 is a user signal generation unit corresponding to a user, 11 is a digital beam former (DBF), 12 is a user signal multiplexing unit corresponding to antennas 0, 1 and 2, 13 is a phase correction circuit having a complex multiplier, 14 is a calibration signal adding unit having an adder, and 15 is digital DA converter for converting a signal into an analog signal, 16 is a transmission radio circuit corresponding to antennas 0, 1 and 2, 17 is a directional coupler for branching the transmission signal, 18 is a multiplexing circuit, 19 is a reception radio circuit, and 20 is analog AD converter which converts a signal into a digital signal, 21 is a scheduler, 22 is a switching circuit (SW), 23 is a calibration signal generation circuit, 24 Calibration signal extracting circuit, 25 denotes a phase error detection circuit.

  User-compatible signals from the user signal generation unit 10 are weighted by the digital beamformer 11, and a user signal multiplexing unit 12 multiplexes a plurality of user-compatible signals for the antennas 0, 1, and 2, Input to the phase correction circuit 13. The calibration signal generation circuit 23 generates a calibration signal obtained by performing spreading processing by multiplying a known transmission information symbol by a spreading code, and adding the generated calibration signal to the calibration signal via the switching circuit 22. Input to the circuit 14. The calibration signal adding circuit 14 adds the calibration signals to the signals corresponding to the antennas 0, 1, and 2 from the phase correction circuit 13 at different time positions, and converts them into analog signals by the DA converter 15. Then, the signal is modulated into a radio frequency signal by the transmission radio circuit 16 and transmitted from the antennas 0, 1 and 2 via the directional coupler 17.

  Also, a part of the radio frequency signal output from the transmission radio circuit 16 is branched by the directional coupler 17, and the calibration signal added to the transmission signal in a time-division manner is time-multiplexed by the multiplexing circuit 18, and the reception radio circuit 19 To enter. The reception radio circuit 19 has a configuration including one demodulation circuit, and demodulates the calibration signals corresponding to the antennas 0, 1, and 2 in a time division manner and converts them into digital signals by the AD converter 20. And input to the calibration signal extraction circuit 24. Further, the scheduler 21 controls the switching circuit 22 and the phase difference detection circuit 25 according to the calibration schedule, and the calibration signal from the calibration signal generator 23 is placed at a different time position with respect to the transmission signal by the switching circuit 22. The signal is added by an adder corresponding to the antennas 0, 1 and 2 of the calibration signal adding circuit 14.

  Corresponding to the switching control of the switching circuit 22, the phase error detection circuit 25 is controlled to detect the phase error of the transmission path to which the calibration signal is added, thereby correcting the signal (complex signal) for correcting the phase error, The signal is input to the complex multiplier corresponding to the antennas 0, 1, and 2 of the phase correction circuit 13. Accordingly, processing can be performed in advance so as to cancel the phase error component of the transmission radio circuit 16 corresponding to the antennas 0, 1, and 2, so that the transmission directivity by the array antenna can be set as a desired direction. In this case, an amplitude adjustment circuit (not shown) for adjusting the amplitude of the calibration signal generated by the calibration signal generation circuit 23 is provided so that the SIR by the calibration signal and the transmission signal becomes constant. Can be controlled. Although the case of the number of antennas 3 is shown, it is possible to provide a larger number of antennas, and each part has a configuration corresponding to the number of antennas.

  With the above-described configuration, the calibration signal is input to the transmission radio circuit 16 corresponding to the antennas 0, 1, and 2 in a time division manner. Therefore, it is input in a time division manner, so that only one demodulator circuit for demodulating the calibration signal is required. Based on the demodulated output signal of the calibration signal, the amount of phase rotation in the transmission radio circuit 16 corresponding to the antennas 0, 1, and 2 can be detected.

  FIG. 2 is an explanatory diagram of the calibration process, and shows the array antenna calibration process with the configuration shown in FIG. 1. FIGS. 2A to 2D show the calibration signal generation and the transmission signal. (E) to (g) indicate calibration signal extraction processing, and (h) and (i) indicate phase detection processing. Calibration signals CalSig0, CalSig1, and CalSig2 obtained by multiplying a known transmission information symbol by a spreading code by the calibration signal generation circuit 23 and performing spread modulation are generated as shown in FIG. Are input to the calibration signal adding circuit 14 and input to the adders corresponding to the antennas 0, 1 and 2 as shown in (b), (c) and (d). In this case, the spreading codes are not different depending on the antennas 0, 1, and 2, but even if they are the same, they become calibration signals at different positions on the time axis. Correspondingly, a phase error can be detected.

The calibration signal from the calibration signal generation circuit 23 is the calibration signal CalSig0 shown in (e) after the loop delay of the feedback loop including the transmission radio circuit 16 and the reception radio circuit 19 corresponding to the antennas 0, 1, and 2. , CalSig1, CalSig2 are input to the calibration signal extraction circuit 24, and are subjected to despreading processing using the calibration signal extraction spreading code shown in (f), and the transmission symbols Symbol0, Symbol1, As shown in (h), the phase error detection circuit 25 performs phase error detection using the transmission symbols Symbol 0 and Symbol 1 and phase error detection using the transmission symbols Symbol 0 and Symbol 2. If based on integration, obtain the calibration weights W _10, W ₂₀ which corresponds to the phase error of the system of antennas 1 and 2. (I) shows the calibration wait timing of the phase detection process.

  The phase error detection signal detected by the above-described phase error detection circuit 25 is input to the phase correction circuit 13 to correct the phase of the transmission signal corresponding to the antennas 0, 1, and 2, so that the transmission radio circuit 16 and so on. Thus, the desired transmission directivity by the array antenna using a plurality of antennas 0, 1, and 2 can be obtained. Further, since the calibration signal is added to the transmission signal in a time division manner to obtain a correction value, as described above, the configuration for demodulating the calibration signal is sufficient even when the number of antennas is increased. This is an economical structure. In addition, the spreading code when applied to the W-CDMA system can be of a single type or several types regardless of the number of antennas, and there is an advantage that the assignment of spreading codes corresponding to users is not affected.

  FIG. 3 is an explanatory diagram of a second embodiment of the present invention. The same reference numerals as those in FIG. 1 denote the same names, 26 denotes a memory, and 27 denotes a delay circuit. The delay circuit 27 includes a case in which delay units D0, D1, and D2 that delay the calibration signal from the calibration signal generation circuit 23 with different delay times are provided for the antennas 0, 1, and 2, respectively. The calibration signal generated by the calibration signal generation circuit 23 is given different delays corresponding to the antennas 0, 1, 2 by the delay circuit 27, and each of the antennas 0, 1, 1 is received by the calibration signal addition circuit 14. 2 is added to the transmission signal transmitted from 2. At this time, the delay difference corresponding to the antennas 0, 1, and 2 needs to be 1 chip (diffusion) or more.

  This makes it possible to identify the signals for the antennas 0, 1, 2 when despreading. The transmission signal including the calibration signal input to the reception radio circuit 19 is stored in the memory 26 for a certain time. The calibration signal extraction circuit 24 extracts a transmission symbol from the transmission signal including the calibration signal in a time division manner. Then, the phase error detection circuit 25 calculates the phase rotation amount in the transmission radio circuit 16 corresponding to the antennas 0, 1 and 2, and the phase correction circuit 13 corrects it. It is also possible to provide an amplitude adjustment circuit (not shown) that adjusts the amplitude of the calibration signal from the calibration signal generation circuit 23.

  The second embodiment also has the same effect as the first embodiment and adds a calibration signal to a transmission signal corresponding to an antenna so that it can be identified by a delay time. As compared with the case of adding to, the phase correction cycle can be shortened because of continuous addition. This is advantageous when the phase variation of the transmitting radio circuit is early.

  FIG. 4 is an explanatory diagram of a third embodiment of the present invention. The same reference numerals as those in FIGS. 1 and 3 indicate the same name, 30 indicates a transmission level monitoring circuit, and 31 indicates a spread length calculation circuit. The transmission level monitoring circuit 30 detects the level of the transmission signal corresponding to the antennas 0, 1 and 2 from the user signal multiplexing unit 12 and inputs it to the diffusion length calculation circuit 31. If the amplitude value of the calibration signal from the calibration signal generation circuit 23 is a fixed value, the level of the calibration signal becomes inappropriate when the level of the transmission signal varies. Therefore, the diffusion length calculation circuit 31 calculates the diffusion length based on the transmission signal level calculated by the transmission level monitoring circuit 30. The calculation of the diffusion length is performed so that the SIR based on the calibration signal level (S) and the transmission signal level (I) after the back calculation by the calibration signal extraction circuit 24 becomes a value satisfying the calibration accuracy.

  Therefore, the same effects as those of the first and second embodiments can be obtained, and the calibration accuracy can be maintained even if the level of the transmission signal varies. This is because the diffusion length is set so that the SIR is constant. For example, if the calibration accuracy (phase error) is σ = 0.5652 deg, and the transmission level is increased by 10 dB, the calibration error σ = 5.652 deg and the phase error is deteriorated by one digit. Thus, the SIR can be maintained substantially constant by controlling the diffusion length of the calibration signal in accordance with the transmission level.

  FIG. 5 is an explanatory diagram of Embodiment 4 of the present invention. The same reference numerals as those in the above-described respective drawings indicate the same names, 32 indicates an amplitude value calculation circuit, and 33 indicates a multiplier. In the fourth embodiment, the transmission signal level corresponding to the antennas 0, 1, and 2 from the user signal multiplexing unit 12 is calculated by the transmission level monitoring circuit 30, and the transmission signal level of the transmission signal is calculated by the amplitude value calculation circuit 32 based on the calculation result. The amplitude value is calculated, and the multiplier 33 controls the amplitude value of the calibration signal from the calibration signal extraction circuit 24. For example, if the amplitude value of the calibration signal from the calibration signal generation circuit 23 is a fixed value, the level of the calibration signal becomes inappropriate when the level of the transmission signal varies. Therefore, the amplitude value calculation circuit 32 calculates the amplitude value based on the level of the transmission signal calculated by the transmission level monitoring circuit 30. The calculation of the amplitude value is performed so that the SIR based on the calibration signal level (S) and the transmission signal level (I) after the back calculation by the calibration signal extraction circuit 24 becomes a value satisfying the calibration accuracy. It is.

  Therefore, the same effects as those of the first to third embodiments can be obtained, and the calibration accuracy can be maintained even if the transmission signal level fluctuates. This is because the amplitude value is set so that the SIR becomes constant. For example, if the calibration accuracy (phase error) is σ = 0.5652 deg, and the transmission level is increased by 10 dB, the calibration error σ = 5.652 deg and the phase error is deteriorated by one digit. As described above, the SIR can be maintained substantially constant by controlling the amplitude value of the calibration signal in accordance with the transmission level.

  FIG. 6 is an explanatory diagram of the fifth embodiment of the present invention. The same reference numerals as those in the above-described drawings indicate the same names, and 34 indicates a calibration error monitoring unit. The fifth embodiment shows a case corresponding to the configuration in which the calibration error monitoring unit 34 is added to the fourth embodiment shown in FIG. 5, and the calibration error monitoring unit 34 also corresponds to the other embodiments described above. It is possible to provide it. The calibration error monitoring unit 34 detects, for example, a phase variation in the transmission radio circuit 16 through a signal path (not shown), and if the error becomes larger than the specification of the array antenna transmission device, the calibration signal The generation circuit 26 can be activated to calibrate the array antenna. Alternatively, by processing the uplink TPC bits for each adaptive array target user, it is determined that the transmission directivity is no longer the desired direction when it is detected that it is necessary to control in the direction of increasing the downlink transmission power, and calibration is performed. It is also possible to adopt a configuration that controls to start the operation.

  FIG. 7 is an explanatory diagram of calibration processing in the configuration shown in FIG. 6, (a) is a calibration start signal, (b) to (e) are calibration signal generation and addition processing to a transmission signal, (F) to (h) indicate calibration detection processing, and (i) and (j) indicate phase detection processing. Calibration is started at the timing shown in (a) by the calibration error monitoring unit 34 described above. In this case, the calibration signal generation circuit 26 generates and outputs a calibration signal CalSig obtained by multiplying a known transmission information symbol by a spreading code, as shown in FIG. The delay signals D0, D1, and D2 of the delay signal including zero delay cause the calibration signals CalSig0, AlSig1, as CalSig2, and input to the antenna 0,1,2 corresponding adder of the calibration signal adding circuit 14 adds to the transmission signal. In this case, the delay time difference between the delay units D0, D1, and D2 of the delay circuit 27 is set to be one chip or more corresponding to the antennas 0, 1, and 2, as described above.

After the loop delay of the feedback loop including the transmission radio circuit 15, the multiplexing circuit 16, the reception radio circuit 19 and the like corresponding to the antennas 0, 1 and 2, calibration signals CalSig0 and CalSig1 corresponding to the antennas 0, 1 and 2 shown in FIG. , CalSig2 are input to the calibration signal extraction circuit 24 in a time multiplexed state, and are subjected to despreading processing using the calibration signal extraction spreading code shown in (g), as shown in (h). Can be separated as time-multiplexed transmission symbols Symbol 0, Symbol 1, Symbol 2, and as shown in (i), the phase error detection circuit 25 performs phase error detection based on the transmission symbols Symbol 0, Symbol 1, calibration weight _W 10 corresponding to the error, _{W 2} The seek. (J) shows the calibration wait timing of the phase detection process.

  Therefore, by generating a calibration signal and calibrating the array antenna only when the state in which the transmission directivity is deviated from the desired direction is determined, for example, by detecting the TPC bit described above, An error in transmission directivity can be corrected.

It is explanatory drawing of Example 1 of this invention. It is explanatory drawing of a calibration process. It is explanatory drawing of Example 2 of this invention. It is explanatory drawing of Example 3 of this invention. It is explanatory drawing of Example 4 of this invention. It is explanatory drawing of Example 5 of this invention. It is explanatory drawing of a calibration process.

Explanation of symbols

0, 1, 2 Antenna 10 User signal generator 11 Digital beamformer (DBF)
DESCRIPTION OF SYMBOLS 12 User signal multiplexing part 13 Phase correction circuit 14 Calibration signal addition part 15 DA converter 16 Transmission radio | wireless circuit 17 Directional coupler 18 Multiplex circuit 19 Reception radio | wireless circuit 20 AD converter 21 Scheduler 22 Switching circuit (SW)
23 Calibration signal generation circuit 24 Calibration signal extraction circuit 25 Phase error detection circuit

Claims (5)

In an array antenna transmission apparatus having a transmission radio circuit corresponding to a plurality of antennas and capable of controlling transmission directivity by the plurality of antennas,
A calibration signal generation circuit for generating a calibration signal;
A calibration addition circuit for adding a calibration signal from the calibration signal generation circuit to a different time position with respect to a transmission signal input to the transmission radio circuit corresponding to the antenna;
A multiplexing circuit for partially branching and multiplexing the output signal of the transmission radio circuit;
A receiving radio circuit for receiving and demodulating a signal multiplexed by the multiplexing circuit;
A calibration signal extraction circuit for extracting a calibration signal corresponding to the antenna from a demodulated output signal of the reception radio circuit;
A phase error detection circuit for obtaining a phase rotation amount of a transmission path including the transmission radio circuit based on the calibration signal corresponding to the antenna extracted by the calibration signal extraction circuit;
An array antenna transmission apparatus comprising: a phase correction circuit that performs phase correction by multiplying a transmission signal input to the transmission radio circuit based on the phase rotation amount obtained by the phase error detection circuit.   Delay that the calibration signal from the calibration signal generation circuit is delayed so as to have a different delay time with respect to the transmission signal that is input to the transmission radio circuit corresponding to the antenna, and that is input to the calibration signal addition circuit 2. The array antenna transmission apparatus according to claim 1, further comprising a circuit.   A transmission level monitoring circuit for monitoring the transmission level of a transmission signal input to the antenna-compatible transmission radio circuit, and a known spread code length corresponding to the transmission level by the transmission level monitoring circuit to determine the known calibration signal generation circuit 3. An array antenna transmission apparatus according to claim 1, further comprising: a spreading length calculation circuit that controls a spreading code for spreading and coding transmission information symbols.   A transmission level monitoring circuit for monitoring the transmission level of the transmission signal input to the antenna-compatible transmission radio circuit, and an amplitude value calculation for controlling the amplitude value of the calibration signal corresponding to the transmission level by the transmission level monitoring circuit 3. The array antenna transmission apparatus according to claim 1, further comprising a circuit.   Calibration that monitors the phase error of the transmitting radio circuit corresponding to the antenna, detects that a preset phase error increase condition has been met, activates the calibration signal generation circuit, and executes a calibration process The array antenna transmission apparatus according to claim 1, further comprising an error monitoring unit.

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