WO2005041443A1

WO2005041443A1 - Wireless communication apparatus

Info

Publication number: WO2005041443A1
Application number: PCT/JP2004/016073
Authority: WO
Inventors: Naoki Ohnishi; Masaki Suto
Original assignee: Hitachi Kokusai Electric Inc.
Priority date: 2003-10-27
Filing date: 2004-10-22
Publication date: 2005-05-06
Also published as: JP4384892B2; JP2005130315A

Abstract

In a wireless communication apparatus of, for example, a base station apparatus having an adaptive array antenna, a high-precision antenna calibration can be realized even when the number of the antennas constituting the array antenna is large. There are provided a plurality of calibration antennas (I1-IM) used for executing calibration processings related to the systems of antennas (A1-AN) used for wireless communication. Antenna system calibration processing executing means uses the plurality of calibration antennas (I1-IM) as the antenna array to execute the calibration processing related to the antenna systems.

Description

Wireless communication device

TECHNICAL FIELD The present invention relates to a radio communication device such as a base station device provided with an adaptive array antenna, and more particularly to a radio communication device having a large number of antennas constituting an array antenna.

Even in this case, the present invention relates to a wireless communication device that realizes highly accurate antenna calibration. book

BACKGROUND ART For example, mobile radio communication systems such as a mobile phone system and a personal handy phone system (PHS), and a base station equipped with an adaptive array antenna composed of a plurality of antennas. 2. Description of the Related Art Wireless communication with a mobile station device is performed by a device. Further, in such a base station apparatus, an error between transmission processing and reception processing for each antenna, an error between transmission processing or reception processing for a plurality of antennas, and an error between reception processing are corrected (calibrated). The antenna is calibrated (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2002-26261

'Disclosure of the Invention However, in a conventional base station apparatus equipped with an adaptive array antenna, for example, when the number of antennas constituting the array antenna is large, There was a problem that the accuracy of the vibration was insufficient. In addition, for example, there is a demand for lowering the level of a signal for performing calibration to suppress interference and a demand for allowing operation to be continued even if a failure occurs in a calibration antenna. Was.

The present invention has been made in view of such a conventional situation. For example, even when the number of antennas constituting an array antenna is large, a radio which can realize a highly accurate antenna calibration is provided. It is intended to provide a communication device.

Another object of the present invention is to provide a wireless communication device capable of suppressing interference by lowering the level of a signal for performing calibration, for example.

Another object of the present invention is to provide a wireless communication device that can continue operation even when a failure occurs in a calibration antenna, for example.

In order to achieve the above object, the wireless communication device according to the present invention performs wireless communication using an antenna as the following configuration.

That is, a plurality of calibration antennas used to execute a calibration process related to the antenna system are provided, and the antenna system calibration process execution means uses the plurality of calibration antennas as an array antenna. To perform the calibration process for the antenna system.

Therefore, a plurality of calibration antennas are used as an array antenna, and the calibration process relating to the wireless communication antenna system is not performed, so that highly accurate antenna calibration can be realized. For example, even when the number of antennas constituting an array antenna for wireless communication is large, a high-precision antenna calibration is required.

—You can achieve shilling. In addition, since a plurality of calibration antennas are used as an array antenna, the reception sensitivity is improved, so that, for example, the level of a signal for performing calibration can be lowered, and the It is possible to suppress interference.

Here, the number of antennas used for performing wireless communication is not particularly limited, and may be one, or may be two or more.

Further, the number of the plurality of antennas used for executing the calibration process for the antenna system is not particularly limited, and various numbers may be used.

The wireless communication includes, for example, wirelessly transmitting a signal to a wireless communication device as a communication partner and receiving a signal wirelessly transmitted from a wireless communication device as a communication partner. .

Various processes may be used as the calibration process for the antenna system. For example, a signal amplitude error and a signal phase error related to transmission, reception, and transmission / reception of an antenna system used for wireless communication may be used. A process for correcting is used.

Various signals may be used as the signal for performing the calibration. For example, a communication signal wirelessly transmitted from a wireless communication antenna used for wireless communication to a communication partner may be used. Alternatively, a dedicated signal for calibration may be prepared and used. The signal for performing the calibration is wirelessly transmitted from, for example, an antenna for wireless communication and received by the antenna for calibration.

Further, with respect to the antenna for calibration and the antenna for wireless communication, various antennas may be used as the respective antennas. Also, various antenna arrangements may be used.

In the wireless communication apparatus according to the present invention, as one configuration example, the antenna-based calibration processing execution means may include any one of the obstacles related to one of the calibration antennas. If an error occurs, the calibration process for the antenna system is executed using the calibration antenna excluding the calibration antenna in which the failure occurred.

Therefore, for example, even when a failure occurs with respect to some of the calibration antennas, the calibration process can be performed. The operation of wireless communication using the communication antenna can be continued.

Here, as a case where a failure related to the calibration antenna occurs, a case where a failure related to an arbitrary number of calibration antennas may be used, for example, one calibration antenna may be used. In the case where a failure has occurred with respect to, or in the case where a failure has occurred with two or more calibration antennas in addition to the above case, it can be used.

In addition, various methods may be used as a method of grasping that a failure related to the calibration antenna has occurred. For example, a method for detecting the occurrence of a failure related to the calibration antenna may be used. A configuration including antenna failure detection means may be used, or a configuration in which a failure related to a specific calibration antenna is input from an external device user or the like may be used. You may be.

Further, various types of faults related to the calibration antenna may be used. For example, a fault in the calibration antenna system is used. Specifically, a fault in the calibration antenna or a fault in the calibration antenna is used. Failures such as receiving circuits other than the antenna for calibration are used.

—As an example of configuration, if a failure occurs in any of the antennas, notify the management to that effect.

The wireless communication device according to the present invention has the following configuration as one configuration example. That is, a plurality of antennas for wireless communication used for performing wireless communication are provided, and the wireless communication means performs wireless communication using the plurality of antennas for wireless communication as an array antenna.

Further, the plurality of antennas for wireless communication are divided into two or more groups. Then, the antenna system calibration processing means executes a calibration process regarding the antenna system for each group for the antenna for wireless communication.

Therefore, the multiple antennas for wireless communication are divided into two or more groups, and the calibration process for the antenna system is executed for each group, thereby improving the efficiency of the calibration for the antenna system as a whole. Can be done.

As an example, by performing a common calibration process for all the wireless communication antennas included in each group, the number of calibration processes for the antenna system can be reduced as a whole It is.

As another example, it is also possible to use a mode in which the calibration process for the antenna system is executed in order for each of the antennas for wireless communication included in the group for each group.

Here, various numbers may be used as the number of two or more groups related to the antenna for wireless communication.

Further, the number of wireless communication antennas included in each group is not particularly limited. For example, two or more wireless communication antennas may be included in all groups, or one wireless communication antenna may be included. An embodiment may be used in which there is one or more groups including only communication antennas.

Hereinafter, a configuration example according to the present invention will be further described.

As one configuration example, a signal (for example, a communication signal or a signal for calibration) wirelessly transmitted from a wireless communication antenna used for wireless communication is used to execute a calibration process for an antenna system. Carriers used The signal is received by the shaking antenna, and the calibration process for the antenna system is executed based on the receiving result.

As an example of the configuration, the calibration processing is sequentially performed on a plurality of antenna systems used for wireless communication one by one.

As a configuration example, a plurality of calibration antennas are used as an adaptive array antenna.

As one configuration example, the plurality of antennas for wireless communication are:

Used as na.

As one configuration example, the frequency (first frequency) of the communication signal wirelessly received from the communication partner by the wireless communication means, the frequency (second frequency) of the communication signal wirelessly transmitted to the communication partner by the wireless communication means, and the like. Are different.

Here, various communication partners may be used. As an example, when the wireless communication device according to the present invention is applied to a base station device of a mobile wireless communication system, a mobile station device or the like can be used as a communication partner.

Various signals may be used as a communication signal wirelessly received from a communication partner and a communication signal wirelessly transmitted to the communication partner.

Further, various frequencies may be used as the first frequency and the second frequency, respectively.

As one configuration example, in each of the calibration antenna systems, a predetermined frequency component extraction unit extracts a component of a predetermined frequency from a signal wirelessly received by the calibration antenna. Further, the antenna system calibration processing execution means weights and combines the extraction results of the plurality of antenna systems for calibration by the predetermined frequency component extraction means, and performs the calibration processing on the antenna system based on the weighted synthesis results. Execute.

As one configuration example, the transmission system and the reception A common antenna is shared with the system. As another configuration example, separate antennas are used for the transmission system and the reception system for each wireless communication antenna. Brief Description of Drawings

FIG. 1 is a diagram showing a configuration example of a portion related to an adaptive array antenna of a base station apparatus according to one embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration example of a base station device and the like.

FIG. 3 is a diagram showing an example of an antenna pattern of an adaptive array antenna.

FIG. 4 is a diagram showing a configuration example of an adaptive array antenna device in an FDD system.

FIG. 5 is a diagram showing an example of a reception pattern and a transmission pattern having a deviation in the adaptive array antenna. BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment according to the present invention will be described with reference to the drawings.

In the present embodiment, a moving object including an adaptive array antenna composed of a plurality of N systems and a calibration adaptive array antenna composed of a plurality of M systems is provided. The case where the present invention is applied to a base station apparatus for wireless communication is shown. In the present embodiment, a case is shown in which a calibration process such as an antenna transmission / reception calibration is performed.

FIG. 1 shows a configuration example of a portion related to an adaptive array antenna of a base station apparatus according to one embodiment of the present invention.

In the base station apparatus of this example, as processing units for performing wireless communication with a mobile station apparatus or the like as a communication partner, antennas A1 to AN and transmission / reception switching switches are provided for each of N systems. Switches (SW) B1 to BN, receiving circuits (Rx) C1 to CN, AZD (Analog to Digital) converters (ADC) D1 to DN, and antennas A1 to AN A1 to EN for multiplying the reception weights of A1 to AN, and multipliers F1 to FN for multiplying the transmission signal by the transmission weight of each antenna A1 to AN, and D / A ( Digital to Analog) converters (DACs) G1 to GN and transmission circuits (Tx) Η1 to ΗΝ are provided.

In addition, the base station apparatus of this example has a processing unit for performing wireless communication with a mobile station apparatus or the like as a communication partner. An adder 1 for summing the signals to obtain a received signal as an entire adaptive array antenna, and receiving antennas for each of the antennas A 1 to AN based on the received signal, and transmitting for each of the antennas A 1 to AN A weight calculation / calibration circuit 2 for calculating weights and performing calibration processing is provided.

Further, in the base station apparatus of this example, as a processing unit for performing calibration of the antenna system, the antennas I1 to IM, the receiving circuits (Rx) J1 to JM, AZD (Analog to Digital) converters (ADCs) K1 to KM and multipliers L1 to LM for multiplying the reception signals of each antenna I1 to IM by the reception weight of each antenna I1 to IM Has been.

In the base station apparatus of this example, as a processing unit for calibrating the antenna system, the signals received by each of the antennas I 1 to IN after receiving weight multiplication are summed in common to the M systems. Calibration

An adder 11 for obtaining a received signal (calibration received signal) as a whole, and a weight calculation / phase setting circuit 12 for calculating the reception weight of each of the antennas I 1 to IN based on the received signal are provided. I have.

An example of an operation performed by the base station device of the present example will be described.

In addition, N keys, which are processing units that perform wireless communication with a mobile station device or the like that is a communication partner. As the operation of the antennas A1 to AN, for example, a general operation can be used, and therefore, in this example, the M antennas I which are the processing units for performing the calibration of the antenna system are used. 1 to IM operations will be described in detail.

In the base station apparatus of the present example, a plurality of calibration antennas (calibration antennas) I1 to IM constitute an array antenna, and there are M calibration antennas (# C1 to #CM).

In this example, the calibration antennas I1 to IM are reception-only array antennas.

In this example, the signals transmitted wirelessly from the array antennas A1 to AN for wireless communication are received and processed by the system of array antennas I1 to IM for calibration, so that the array antenna A1 for wireless communication is received. Execute the calibration process for the ~ AN system.

Each of the calibration receiver circuits J1 to JM transmits radio waves with a known amplitude and phase in order from N antennas A1 to AN, which contribute to the antenna pattern of wireless communication. The reception processing is performed by each of the antennas I1 to IM. Each of the receiving circuit units J1 to JM performs, for example, a band limitation by a filter or the like and a designated phase control on the received signal.

The received signal of each calibration antenna system is converted from an analog signal to a digital signal (digital value) by the AZD converters Kl to KM.

Weight calculation ・ Phase setting circuit 12 performs appropriate weight calculation based on the calibration reception signal, and supplies the reception weight of each calibration antenna system reflecting the result to each of multipliers L1 to LM I do. Weight calculation: The phase setting circuit 12 performs appropriate phase setting, for example, corresponding to each calibration antenna system circuit, and outputs phase control information to each of the receiving circuits J1 to JM. I do.

AZD converter K1 ~ KM of each calibration antenna system The received signal converted to the digital value is weighted with a complex amplitude by complex multiplication of each receiving weight in each of the multipliers L1 to LM, and is controlled to be converted to an appropriate level.

Thereafter, the received signals after receiving weight multiplication output from the multipliers L1 to LM are added (synthesized) by the adder (synthesizer) 11 for all the calibration antenna systems, and the addition result is obtained. Output as a calibration reception signal.

In this example, the circuit units of these calibration antenna systems operate as so-called phased array circuits.

Weight calculation 'Phase setting circuit 12' may be composed of various types, for example, DSP (Digital Signal Processor) or FPGA (Field Programmable Gate Array), etc., easily realize digital signal processing It is preferable to use a structure that can be used.

As described above, the weight calculation and phase setting circuit 12 calculates the antenna pattern of the calibration antenna, the calculation of the amplitude weight or the calculation of the phase weight, and the array sequence for calibration (antenna I 1 to IM). Calculate the phase settings up to. In this example, the configuration is such that the phase of the analog reception signal is controlled in each of the receiving circuits J1 to JM. However, as another configuration example, the configuration may be such that phase control is performed by digital signal processing. is there.

As described above, the base station apparatus of this example has the same array system (# C1 to # CM) in which the number of array elements that do not contribute to the antenna pattern of wireless communication is M (M is a natural number of 2 or more). These array systems function as array antennas for performing calibration. '

Here, in the base station device of this example, N (N is a natural number of 2 or more) N that contributes to the radio communication radiation is considered in consideration of the antenna pattern in all phases and amplitudes in the number M of array elements. Preliminary information on the absolute amount of phase and amplitude of radio waves received from array elements The weight calculation and the phase setting circuit 12 are operated based on such a table of information.

In the case of a base station apparatus in which a communication array antenna is composed of N antennas A1 to AN as in this example, the calibration timing is, for example, from the first antenna A1. Calibration is performed in order up to the Nth antenna AN, and calibration is performed sequentially for each antenna A1 to AN in a frame in which calibration is permitted.

Specifically, in one calibration, one of the antennas A1 to AN that contributes to the radiation of wireless communication wirelessly transmits a signal with a weak amplitude at a known amplitude and a known phase from one of the antennas A1 to AN. Then, the signal is received by a calibration array antenna composed of M antennas I1 to IM. After the calibration of all array systems # 1 to #N is completed, for example, a mode in which calibration is continuously performed may be used, or the calibration may be periodically performed at an arbitrary time interval. A mode in which the solution is performed may be used.

Also, in the base station apparatus system of the present example, for example, when a failure occurs in one or more antennas or a plurality of antennas of the calibration array systems # C1 to #CM, This is determined, for example, from the calibration reception signal. Then, when such a failure occurs, it is possible to continue the operation by forming an antenna beam in each of the array systems except for the array system in which the failure has occurred in the carrier precision system. Further, when such a failure occurs, it is also possible to adopt a configuration in which information about the failure is notified to a management center or the like. '

Here, when a failure occurs in one or more antennas constituting the array antenna and the total number of antennas constituting the array antenna changes, it is usually necessary to change the control method. For this reason, for example, an array antenna is configured in advance. Prepare an algorithm when a part of the antenna is missing.

Specifically, for the calibration system, in addition to the algorithm when M antennas operate as array antennas, any one of them is missing and the remaining (M-1) antennas operate as array antennas. For example, in the case where two antennas are missing and the other (M-2) antennas operate as an array antenna, each antenna pattern with some missing antennas is used. Prepare a suitable algorithm and switch to use it.

Similarly, with respect to the N antennas A1 to AN that perform wireless communication, algorithms corresponding to various patterns can be prepared and used when a failure occurs.

If the total number of calibration-based array systems decreases by 1 or more due to such a failure, the antenna beam gain changes and the gain decreases compared to normal operation. It is considered that the performance is deteriorated compared to the normal operation. For this reason, it is possible to continue the operation, but it is desirable to carry out maintenance immediately.

Further, in the base station device of the present example, for example, elements having the number N of array elements that contribute to the antenna pattern of wireless communication can be grouped.

As an example, N antennas A 1 to A 1 to antennas I 1 to IM are grouped so that antennas with little difference in the level and phase of signals (transmitted signals) received by IM are grouped into the same group. Divide AN into multiple d groups.

When calibration is performed for each group of d groups, the number of times of performing calibration is d times compared to, for example, the case where calibration is performed for N antennas A1 to AN one by one. It is possible to reduce the number of times to (dZN) times. Also, for example, assuming that the number of antennas included in each group is the same (NZ d), for each of the d groups, If the antennas included in these groups are calibrated one by one, the number of calibrations performed in each group can be (NZ d).

As described above, in the base station apparatus of this example, the number of array elements contributing to the antenna pattern for wireless communication or calibration is (N + M), and a plurality of N antennas are used for wireless communication. M antennas are used as array antenna elements for calibration.

With the M calibration antennas, for example, the calibration time can be reduced by simultaneously performing the calibration. Also, when the number of array antenna elements is large, the mutual coupling between the antennas is very small in some cases.Therefore, preparing a plurality of calibration antennas and grouping the antenna groups for calibration Is also possible.

Further, in such a configuration, when a failure occurs in one or more of the antennas constituting the array antenna, for example, an antenna beam is formed in an array system excluding the number of the failed antenna elements, and M antenna beams are formed. It is also possible to use this antenna as an antenna for calibration.

Next, the embodiment described above will be further described.

FIG. 2 (a) shows an example of the overall configuration of the base station apparatus.

The base station device shown in FIG. 2A includes, for example, an adaptive array antenna unit (AAA unit) 21 including an antenna, a transmission / reception unit, and a weight calculation unit, and modulation and demodulation of a communication signal. Modem section (modem section) 22 that performs, baseband section (BB section) 23 that performs baseband (BB) processing, and control section 24 that controls these processing sections 21 to 23 , And a base station controller 25.

Here, in the base station apparatus shown in FIG. 2 (a), for example, as a configuration of the AAA unit 21, a configuration relating to an adaptive array antenna as shown in FIG. The formation is used. . As shown in FIG. 11 of the above description, the received and received signal number "" is slightly different from the received and received signal number "". Is input to and output from the modem section 22 22, and the transmission / reception signal '''' is input from the mode modem section 22 22. .

In addition, the overall configuration of the base station equipment and the configuration related to Aadaptive Bua Alley Leia Antentenana. However, the present invention is not necessarily limited to what is shown in the embodiment of the present embodiment, but various types of configuration may be used. 55 can be used. .

FIG. 22 ((bb)) shows the data communication ((TT xx or RR xx)) in the TT DD DD system. One example of a gadget frame in the garbage collection system, and a garbage collection system for data communication in the FF DD DD system ((chome and)) One example of the Dodoff frame is shown. .

In the base station apparatus according to the embodiment of the present embodiment, for example, for example, during the period of the gagardoff frame, such as In some cases, such as when the data is in an area that is not in communication, the calibration is performed. This allows for more efficient processing of the calibration process. This is where you can go to your destination. .

As described above, in the base station apparatus according to the embodiment of the present invention, the wireless communication The number of elementary elements that contribute to the elementary elementary element element of NN, and, for example, in the vicinity of 1155 Relay element number The device has an elementary element element for a MM-capacity re-bracketing operation. . Then, each of the NN books that contributes to the wireless communication communication of Aantante Tenana Papata Turn is 11 from AA11 to AANN In order, the radio wave is transmitted and transmitted in a known amplitude width and a known phase phase, and the radio wave is transmitted to the carrier. Aeontetenana II 11 ~~ II MM to receive and receive. .

As in this example, in the present embodiment, the key is

The antenna pattern, which is composed of 0 groups, and is formed by the calibration array antenna, sequentially receives the calibration data from the wireless communication array antenna and performs the calibration process. Execute

In this embodiment, since the calibration antennas I1 to IM are also array antennas, the signal level for transmitting and receiving signals between antennas may be very low.5 For example, four elements of the calibration antenna To transmit from each antenna to space Power may be as low as 6 dB (25%). This is equivalent to doubling the distance between the antennas for the wireless communication array antennas A1 to AN and the calibration antennas I1 to IM. The mutual coupling with the array antennas A1 to AN for wireless communication is remarkably reduced, and approaches the characteristics of the antenna patterns of the array antennas Al to AN for wireless communication individually.

Further, in the base station apparatus according to the present embodiment, for example, when a failure occurs in one or more of the calibration array elements I1 to IM, the operation of the failed antenna is performed without stopping the operation. Calibration can be performed with each calibration antenna element except for.

Further, in the base station apparatus of the present example, for example, the number of elements of the array element N contributing to the antenna pattern of the wireless communication is divided into a plurality of d groups to reduce the number of times of carrying out the calibration. Can be.

Therefore, in the base station apparatus according to the present embodiment, by providing a plurality of array antenna elements I1 to IM completely independent of the plurality of array antenna elements A1 to AN performing wireless communication, for example, It is possible to dynamically calibrate each array antenna series for wireless communication during operation, and it is possible to perform such calibration using, for example, weak radio waves. Accuracy can be increased. That is, by performing calibration using an array antenna composed of a plurality of antennas I1 to IM, the receiving sensitivity is improved by forming using the calibration antenna.

Further, in the base station apparatus according to the present embodiment, it is possible to suppress the suspension of the system operation due to the failure of one antenna (in this embodiment, the calibration antenna) which is a weak point of the array system. Become.

As an example, in a radio base station apparatus of a mobile communication terminal, antenna calibration can be performed automatically and with high accuracy during operation. Here, in the conventional calibration, it is assumed that the calibration antenna does not affect the array antenna, but in the present embodiment, the calibration antenna does not affect the array antenna. Is assumed.

Also, various positions may be used as the positions of the arrangements of the antennas provided in the base station apparatus according to the present embodiment. For the installation positions of the plurality of antennas and forming by the antennas, for example, an algorithm is prepared corresponding to the pattern of each arrangement.

In this embodiment, a case has been described in which the wireless communication apparatus according to the present invention is applied to a base station apparatus.

Further, in the base station apparatus according to the present embodiment, a plurality of antennas for wireless communication are configured by a plurality of N antennas A1 to AN used for performing wireless communication with a communication partner. The function of performing wireless communication using the antennas A1 to AN constitutes wireless communication means.

Further, in the base station apparatus according to the present embodiment, N antennas A 1 to

A plurality of calibration antennas are configured by a plurality of M antennas I1 to IM used for executing a calibration process for the AN system, and the M antennas I1 to I1 to IM are used. The function of executing the calibration processing for the antenna system by the IM constitutes the antenna system calibration processing execution means.

Further, in this embodiment, the configuration in which the antenna for wireless communication and the antenna for calibration are provided as separate antennas has been described. However, as another configuration example, the antenna for wireless communication and the antenna for calibration are provided. It is also possible to use a configuration in which some or all of the antennas are shared.

The background of the technology relating to the present invention will be described below. The items described here are: Not all are necessarily limited to conventional techniques.

For example, in mobile radio communication, it is very effective to use an adaptive array antenna system to realize high-speed communication. The adaptive array antenna system can direct the peak of the antenna pattern in the direction in which the desired user exists by changing the phase and amplitude of each array sequence. This is adaptive beamforming. In a 7-adaptive array antenna system, for example, in the case of a plurality of N-element antennas, there are N series from # 1 to #N.

In addition, the adaptive array antenna system can direct a null (NULL) of a transmission antenna pattern so as to suppress reception of an interference wave from an undesired user and reduce interference in an undesired user direction. This is adaptive null steering.

In the adaptive array antenna system, adaptive beamforming for communicating with the maximum transmission power is performed for the mobile communication terminal that performs communication with another interfering mobile communication terminal that is not performing communication. Adaptive null steering can be performed so as not to affect them.

FIG. 3 shows an example of adaptive beamforming and adaptive null steering.

Specifically, an antenna 31 of a base station device equipped with an adaptive array antenna and its antenna pattern (directivity pattern) and a plurality of mobile communication terminal devices 41 to 43 are shown.

The beam is directed in the direction of the mobile terminal device 42 corresponding to the desired wave, and the null is directed in the direction of the mobile terminal devices 41 and 43 corresponding to the interference wave.

By the way, in mobile communication, there are TDMA (Time Division Multiple Access) and FDD (Freauency Division Duplex) systems. In a DMA / TDD (Time Division Duplex) communication system, the transmission and reception frequencies are exactly the same. The radio wave propagation environment from the base station device to the user terminal is equal to the radio wave propagation environment from the user terminal side to the base station device, and reversibility of the radio wave propagation environment is established between the base station device and the user terminal.

That is, it is possible to make the reception and transmission antenna patterns of the base station apparatus the same, and it is possible to realize a very simple configuration. These are currently used in PHS (Personal Handy phone System) base station equipment that is partially provided.

On the other hand, in FDD systems such as the PDC (Personal Digital Cellular) system and the CDMA (Code Division Multiple Access) system, since the uplink and downlink frequencies are different, it is necessary to make the reception and transmission antenna patterns exactly the same. Can not.

FIG. 4 shows a configuration example of an adaptive array antenna device in an FDD system.

Specifically, antennas 01 to 〇N, transmission and reception switching switches (SW) P1 to PN, reception circuits (Rx) Q1 to QN, and A / D ( Analog to Digital) Converters (ADC) R1 to RN, multipliers S1 to SN for multiplying the reception signal of each antenna by the reception weight of each antenna, and transmission of each antenna for the transmission signal Multipliers T1 to TN for multiplying weights, DZA (Digital to Analog) converters (DACs) U1 to UN, and transmission circuits (Tx) V1 to VN are provided.

In addition, for each of the N systems, the sum of each antenna reception signal after reception weight multiplication is calculated.

An adder 51 that acquires a received signal as a signal, and a weight calculation circuit 52 that calculates the reception weight of each antenna divided by the transmission weight of each antenna based on the received signal are provided.

FDD system like ί; Based on the received signals for the individual antenna elements (# 1 to #N) 0 1 to ON, the weights of the complex amplitudes corresponding to the individual antenna elements O 1 to {} are determined by the weight calculation circuit 52. Is given to the received signal corresponding to each antenna element 0 1 to ON. At the same time, an expected antenna pattern is formed by adding a correction value (frequency calibration) including the frequency difference component to the weight to the transmission signal from the transmission data. Thereby, the same pattern can be formed in transmission and reception.

However, it is practically difficult to form the same pattern for reception and transmission.

For example, when there is a deviation (variation) in the transmission amplitude and transmission phase characteristics of the transmission analog part and reception analog part of each array series, when a correction weight that includes a frequency difference component for the same weight is used for reception and transmission. In this case, a desired antenna pattern may not be generated because the reception pattern and the transmission pattern are different, and the gain in a desired direction is reduced or the gain for a hired user is increased.

Fig. 5 shows the reception pattern Z by such an adaptive array antenna.

1 and an example of the transmission pattern Z2 are shown, and the reception pattern Z1 and the transmission pattern Z2 are shifted due to a deviation.

Then, as shown in the figure, at the null (NULL) angle estimated from the reception pattern Z1, the side lobe peak of the transmission pattern may be directed, and the desired transmission pattern may not be obtained.

In general, individual hardware calibration is performed as a method of removing such a variation of each array series. More specifically, the deviation between all the reception analog sections and the transmission analog section is measured, the correction amount is calculated in advance, and the weight set for each element in consideration of the correction amount during actual operation. Is calculated.

However, there are cases where the initially obtained correction amount changes during operation. is there. The cause of this is, for example, a change in the characteristics of an analog active component (for example, an amplifier, a mixer, a synthesizer, etc.) due to a difference in outside air temperature between day and night. In addition, other passive components (eg, fillers, power brass, etc.) have some characteristic changes.

The cause may be slight phase fluctuation due to expansion and contraction of the length of the connection cable used inside the device. Alternatively, if the cable connecting the antenna and the amplifier is exposed outdoors, phase fluctuations due to external vibrations such as wind, rain, snow, and the like may be considered.

When such a change occurs, the performance of the adaptive array antenna device is greatly deteriorated. For example, similarly to the antenna pattern shown in FIG. 5, a desired wave and an interference wave (including a noise component) are generated. Degradation of SINR (Signal to Interference plus Noise Rat io), which is the ratio of As a result, interference suppression cannot be performed and communication quality deteriorates. For this reason, calibration is not sufficient at one time, and it is necessary to perform calibration in real time during operation.

In addition, when the number of antenna elements of the adaptive array antenna base station apparatus is large, there is a distance between antennas due to the large number of antenna elements, so that the accuracy of the calibration is not high. For this reason, it is necessary to increase the reference signal level at the time of calibration, but this is not desirable because it causes interference with nearby base station apparatuses. In addition, when the signal level is reduced, the accuracy of the calibration is required, and the specifications required for the calibration antenna are strict. In addition, in the case of a failure of the calibration antenna in an adaptive array system, the base station equipment is immediately stopped by itself, so that both characteristics and reliability are important.

On the other hand, according to the present invention, as described above, such a conventional problem can be solved and an effective effect can be realized. Here, the configurations of the wireless communication device, the communication device, the base station device, and the like according to the present invention are not necessarily limited to those described above, and various configurations may be used. Further, the present invention can be provided, for example, as a method or a method for executing the processing according to the present invention, a program for realizing such a method or method, a recording medium for recording the program, and the like. Yes, and can also be provided as various devices and systems.

Further, the application field of the present invention is not necessarily limited to the above-described fields, and the present invention can be applied to various fields.

Further, as various processes performed in the wireless communication device, the communication device, the base station device, and the like according to the present invention, for example, in a hardware resource including a processor, a memory, and the like, a processor is a ROM (Read Only Memory). A configuration controlled by executing a control program stored in the CPU may be used. For example, each functional unit for executing the processing may be configured as an independent hardware circuit.

In addition, the present invention can be understood as a computer-readable recording medium such as a floppy (registered trademark) disk (CD) or a ROM storing the above-mentioned control program, or the program (itself). The processing according to the present invention can be performed by inputting the control program from the recording medium to a computer and causing the processor to execute the control program.

Industrial applicability

As described above, according to the wireless communication apparatus according to the present invention, the calibration processing for the wireless communication antenna system is performed by using a plurality of calibration antennas as an array antenna. Antenna calibration can be realized. For example, even when the number of antennas constituting an array antenna for wireless communication is large, high-precision antenna calibration is possible. —You can achieve shilling. Further, according to the present invention, for example, it is possible to suppress interference by lowering the level of a signal for performing the calibration, May be able to continue operation.

Claims

The scope of the claims

1. In a wireless communication device that performs wireless communication using an antenna,

A plurality of calibration antennas used to perform a calibration process on the antenna system;

An antenna-based calibration processing executing means for executing a calibration processing related to an antenna system using a plurality of calibration antennas as an array antenna;

A wireless communication device comprising:

2. In the wireless communication device according to claim 1,

The antenna-based calibration processing execution means uses a calibration antenna that excludes the failed calibration antenna when a failure occurs in any of the calibration antennas. To execute the calibration process for the antenna system

A wireless communication device characterized by the above-mentioned.

3. The wireless communication device according to claim 1 or claim 2, wherein a plurality of wireless communication antennas used for performing wireless communication;

Wireless communication means for performing wireless communication using a plurality of wireless communication antennas as an array antenna;

Multiple wireless communication antennas are divided into two or more groups,

The antenna system calibration processing means executes a calibration process for the antenna system for each group with respect to the antenna for wireless communication,

A wireless communication device to be characterized. '