JP4704306B2 - Wireless communication apparatus and calibration method - Google Patents

Description

  The present invention relates to a wireless communication apparatus and a calibration method.

Conventionally, in a time division duplex (TDD) type mobile communication system, for example, Patent Literature 1 discloses a calibration technique for a wireless communication apparatus including an array antenna having a plurality of antenna elements. ing. In the prior art described in Patent Document 1, a calibration unit having a calibration-dedicated transmission / reception circuit that is not used for actual communication is provided separately from a base station transmission / reception unit having an actual communication transmission / reception circuit ( (See FIG. 3 of Patent Document 1). Then, the calibration unit is used to measure the receiving system and transmitting system of the array antenna and calculate the calibration weight.
JP 2006-19991 A

  However, in the conventional technique described in Patent Document 1 described above, since a transmission / reception circuit that is not used for actual communication is provided, there is no problem in terms of cost and miniaturization of the apparatus.

  The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide a wireless communication apparatus and a calibration method capable of sharing a transmission / reception circuit during calibration measurement and during actual communication. There is.

In order to solve the above problems, a wireless communication apparatus according to the present invention measures transmission characteristics of a transmission system and a reception system provided corresponding to each antenna element, and determines transmission characteristics of the transmission system and the reception system. In the wireless communication apparatus that corrects the difference, the first switching is performed between whether the signal of the transmission system of the first antenna element is supplied to the first antenna element or distributed to the reception systems of all the antenna elements. 1 switch means, a distribution means for distributing the signal supplied from the first switch means to the receiving systems of all the antenna elements, and a combining means for combining the signals of the transmission systems of all the antenna elements, Second switch means for switching whether to supply a reception signal of the first antenna element to the reception system of the first antenna element or to supply a signal synthesized by the synthesis means; Comprising a, in the case of the measurement of the reception system characteristic, said first switch means, a signal transmission system of the first antenna element is supplied to the distribution means, in the case of the measurement of the transmission system characteristics, The second switch means supplies the signal combined by the combining means to the reception system of the first antenna element .
According to this configuration, the transmission system and the reception system provided corresponding to the first antenna element transmit and receive signals via the first antenna element during actual communication, and at the time of calibration measurement, the reception system. It can be used as a signal path for measuring characteristics and a signal path for measuring transmission system characteristics.

In the wireless communication apparatus according to the present invention, both the first and second switch means are configured by a single 2-to-2 switch, and the 2-to-2 switch is connected to the first antenna element. An input / output terminal for outputting a signal to be input and a signal output from the first antenna element, an input terminal for inputting a transmission system signal of the first antenna element, and the first antenna element An output terminal for outputting a signal to be supplied to the receiving system, and an input / output terminal for outputting the signal input to the distributing means and for inputting the signal output from the synthesizing means, and measuring the receiving system characteristics In this case, the 2-to-2 switch supplies a signal of the transmission system of the first antenna element to the distribution means, and in the case of measurement of transmission system characteristics, the 2-to-2 switch Is added to the receiving system of the first antenna element by the combining means. Supplying the combined signals, characterized in that.

In the wireless communication apparatus according to the present invention, the first and second switch means are provided for all the antenna elements, and a transmission system for supplying a signal distributed by the distribution means, and the combining means And a third switch means for selecting a receiving system to which the signal synthesized by the above is supplied as a transmission system and a receiving system of any one of the antenna elements . 3 switch means selects a transmission system that supplies a signal distributed by the distribution means, and in the case of measurement of transmission system characteristics, the third switch means determines that the signal synthesized by the synthesis means The receiving system to be supplied is selected .
According to this configuration, the transmission system and reception system used for calibration measurement can be arbitrarily changed by switching the third switch means.

  The calibration method according to the present invention is a calibration method for measuring transmission characteristics of a transmission system and a reception system provided corresponding to each antenna element and correcting a difference in transmission characteristics between the transmission system and the reception system. In the case of measuring the reception system characteristics, the transmission system signal of the first antenna element is switched from being supplied to the first antenna element to being distributed to the reception systems of all the antenna elements. And a process of distributing a transmission system signal of the first antenna element to the reception systems of all the antenna elements, and in the case of measuring transmission system characteristics, transmission of all the antenna elements And a process of switching a signal supplied to the reception system of the first antenna element from a reception signal of the first antenna element to a signal synthesized by the synthesis means. You It is characterized in.

  According to the present invention, the transmission / reception circuit can be shared during calibration measurement and during actual communication.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a block diagram showing a configuration of a wireless communication apparatus according to the first embodiment of the present invention. The radio communication device shown in FIG. 1 is used for a base station in a TDD mobile communication system.
In FIG. 1, the wireless communication apparatus includes a plurality of antenna elements ANT constituting an array antenna, high frequency units 10a and 10b provided corresponding to each of the antenna elements ANT, a communication baseband signal processing unit 20, and a calibration. A baseband signal processing unit 30 for the operation. The high frequency unit 10a is provided for only one antenna element ANT. For other antenna elements ANT, a high-frequency unit 10b is provided.

  The high-frequency unit 10a includes a coupler 11, a 2-to-2 switch 12a, a low noise amplifier (LNA) 13, a down converter 14, an up converter 15, a high power amplifier (HPA) 16, and an attenuator. (Attenuator: ATT) 17 and synthesizer / distributor 18. The high frequency unit 10b includes a coupler 11, a 2-to-1 switch 12b, an LNA 13, a down converter 14, an up converter 15, and an HPA 16.

  In the high frequency unit 10a, the coupler 11 electrically couples the signal line from the synthesizer / distributor 18 to the signal line connecting the 2-to-2 switch 12a and the antenna element ANT. Branch and synthesize signals with each other. As a result, the signal supplied from the 2-to-2 switch 12 a to the antenna element ANT is also supplied to the combiner / distributor 18. The signal supplied from the combiner / distributor 18 to the coupler 11 is also supplied to the 2-to-2 switch 12a.

  The 2-to-2 switch 12a has two input / output terminals, one output terminal, and one input terminal, and can switch the connection between the terminals. One input / output terminal is connected to the coupler 11, the other input / output terminal is connected to the ATT 17, one output terminal is connected to the LNA 13, and one input terminal is connected to the HPA 16. During actual communication, the 2-to-2 switch 12a outputs the input signal from the coupler 11 to the LNA 13 (reception state) at the TDD transmission / reception switching timing, or receives the input signal from the HPA 16 to the coupler 11. Switch output (transmission status). The setting of the 2-to-2 switch 12a at the time of calibration measurement will be described later.

  The LNA 13 amplifies the output signal of the 2-to-2 switch 12a. The down converter 14 converts the output signal of the LNA 13 (radio frequency band signal) into a baseband signal. The up-converter 15 converts the frequency of the baseband signal into a radio frequency band signal. The HPA 16 amplifies the output signal of the up-converter 15 and outputs it to the 2-to-2 switch 12a. The ATT 17 attenuates the level of the signal transmitted and received between the 2-to-2 switch 12a and the combiner / distributor 18. The synthesizer / distributor 18 receives the output signal of the ATT 17, distributes the input signal into a plurality of signals, and outputs them. The distribution destination is the coupler 11 in the own high frequency unit 10a and the coupler 11 in the other high frequency unit 10b. Further, the synthesizer / distributor 18 receives the output signals of the plurality of couplers 11 as distribution destinations, synthesizes the input signals, and outputs them to the ATT 17.

  On the other hand, in the high frequency unit 10b, a 2-to-1 switch 12b is provided instead of the 2-to-2 switch 12a. During actual communication, the 2-to-1 switch 12b outputs the input signal from the coupler 11 to the LNA 13 (reception state) at the TDD transmission / reception switching timing, or receives the input signal from the HPA 16 to the coupler 11. Switch output (transmission status). The setting of the 2-to-1 switch 12b during calibration measurement will be described later. The other parts 11, 13, 14, 15, 16 of the high-frequency unit 10b are the same as those of the high-frequency unit 10a, and a description thereof is omitted.

  The communication baseband signal processing unit 20 includes an AD converter (Analog-to-Digital Converter) 21, a DA converter (Digital-to-Analog Converter) 22, a reception beam forming unit 23, a reception beam control unit 24, and a transmission beam control unit. 25, a transmission beam forming unit 26, a receiving unit 27, and a transmitting unit 28.

  In the communication baseband signal processing unit, the AD converter 21 converts the output signal of the down converter 14 of each of the high frequency units 10 a and 10 b into a digital signal and outputs the digital signal to the reception beam forming unit 23. The DA converter 22 converts the transmission data corresponding to each antenna element ANT input from the transmission beam forming unit 26 into an analog signal, and outputs the analog signal to the up-converters 15 of the corresponding high frequency units 10a and 10b. The reception beam forming unit 23 demodulates the baseband signals for the number of antenna elements input from the AD converter 21 and calculates a correlation value between the demodulated signals. The reception beam control unit 24 calculates the reception array weight based on the correlation value calculated by the reception beam forming unit 23. The transmission beam control unit 25 calculates the transmission array weight by multiplying the reception array weight calculated by the reception beam control unit 24 by the calibration correction coefficient. The calibration correction coefficient is calculated by the calibration baseband signal processing unit 30. The transmission beam forming unit 26 copies the transmission signal received from the transmission unit 28 by the number of antenna elements, modulates each transmission signal, multiplies each modulation signal by the transmission array weight, and outputs the result to the DA converter 22. The reception unit 27 performs reception processing for receiving a signal transmitted from a desired terminal station based on the reception beam pattern by the reception beam forming unit 23.

  The calibration baseband signal processing unit 30 includes a calibration signal generation unit 31, a transmission / reception system calibration basic correction coefficient calculation unit 32, and a calibration correction coefficient calculation unit 33.

  In the calibration baseband signal processing unit 30, the calibration signal generation unit 31 generates a calibration signal (hereinafter referred to as a Cal signal). The transmission / reception system calibration basic correction coefficient calculation unit 32 calculates a transmission / reception system calibration basic correction coefficient based on the demodulated signal demodulated with respect to the Cal signal by the reception beam forming unit 23 during calibration measurement. The calibration basic correction coefficient for the transmission system is referred to as a TxCal basic correction coefficient, and the calibration basic correction coefficient for the reception system is referred to as an RxCal basic correction coefficient. The calibration correction coefficient calculation unit 33 calculates a calibration correction coefficient (hereinafter referred to as a Cal correction coefficient) based on the RxCal basic correction coefficient and the TxCal basic correction coefficient.

  The radio communication apparatus shown in FIG. 1 performs transmission beam control with the above-described configuration. Specifically, the amplitude and phase of each transmission signal are manipulated by multiplying each transmission signal transmitted from the antenna element ANT by a transmission array weight. As a result, a high gain directivity (beam) is formed in the desired terminal station direction, and an arbitrary transmission beam pattern is formed in the undesired terminal station direction to form a null that cancels the transmission signal. can do. Similarly, a reception beam pattern can be formed by reception beam control. With the transmission beam control and the reception beam control, it is possible to realize space division multiple access (SDMA) using a space (beam pattern) independent of time and frequency in the mobile communication system. According to SDMA, it becomes possible to improve frequency utilization efficiency.

Here, in the mobile communication system of the TDD scheme, if the time slot at the time of transmission and reception can be switched at a sufficiently high speed with respect to the fluctuation speed of the transmission characteristics of the radio propagation path, it can be changed between transmission and reception. It can be regarded as the same propagation path. In this case, with the configuration of FIG. 1 described above, the reception array weight used in the reception beam control can be used as the transmission array weight. However, as shown in FIG. 1, the antenna element is common to the transmission system and the reception system, but other circuits are different between the transmission system and the reception system, so that there is a difference in transmission characteristics between the transmission system and the reception system. . For this reason, calibration for correcting the difference in the transmission characteristics is required.
Hereinafter, the calibration will be described in detail.

  In the calibration method according to the present embodiment, first, an RxCal basic correction coefficient and a TxCal basic correction coefficient are respectively calculated. Next, a Cal correction coefficient is calculated from the RxCal basic correction coefficient and the TxCal basic correction coefficient. Then, the calibration is performed by calculating the transmission array weight by multiplying the reception correction weight by the Cal correction coefficient.

First, with reference to FIG. 2, the operation at the time of calculating the RxCal basic correction coefficient according to the present embodiment will be described. FIG. 2 shows a Cal signal transmission path (thick arrow line in the figure) at the time of calibration measurement for calculating the RxCal basic correction coefficient.
At the time of the calibration measurement for calculating the RxCal basic correction coefficient, the 2-to-2 switch 12a of the high-frequency unit 10a is set to “output the input signal from the coupler 11 to the LNA 13 and output the input signal from the HPA 16 to the ATT 17. Set as follows. In addition, the 2-to-1 switch 12b of each high-frequency unit 10b is set to “output the input signal from the coupler 11 to the LNA 13”.

  The calibration signal generator 31 generates and outputs a Cal signal. The transmission beam forming unit 26 weights the Cal signal by “a transmission array weight in which an element corresponding to the high frequency unit 10a is 1 and an element corresponding to the other high frequency unit 10b is 0”, and the port is directed to the high frequency unit 10a. Only to the DA converter 22. The Cal signal is output from the DA converter 22 to the high frequency unit 10a, and then input to the synthesizer / distributor 18 via the up converter 15, the HPA 16, the 2-to-2 switch 12a, and the ATT 17 in the high frequency unit 10a. The The Cal signals distributed and output from the synthesizer / distributor 18 are input to the couplers 11 of the high frequency units 10a and 10b, and the switches 11a and 12b, the LNA 13 and the down converter 14 from the coupler 11 in the high frequency units 10a and 10b. The signal is input to the AD converter 21 via, converted into a digital signal and input to the reception beam forming unit 23. Since the signal level is amplified in two stages by the HPA 16 of the high frequency unit 10a and the LNA 13 of each high frequency unit 10b, the amount is attenuated by the ATT 17 and the signal level is adjusted.

Here, the following description will be made using variables of complex signal notation.
Let the Cal signal generated by the calibration signal generator 31 be c _Rx (t). Regarding the high-frequency units 10a and 10b corresponding to the k-th antenna element, the transmission characteristics of the transmission system (from the output of the DA converter 22 to the up converter 15 and the HPA 16 and then the switches 12a and 12b) are expressed as h _Tx ^(k) (t) The transmission characteristic of the system (from the switches 12a and 12b to the input of the LNA 13, the down converter 14 and then the AD converter 21) is h _Rx ^(k) (t). Via ATT17 from 2-to-2 switches 12a to the transmission characteristics to the synthetic-distributor 18 and a _Rx in the high frequency portion 10a. The transmission characteristic from the output of the combiner / distributor 18 to the switches 12a and 12b via the coupler 11 is ^defined as d _Rx ^(k) .

Then, the Cal signal y _Rx ^(k) (t) input from the high-frequency units 10a and 10b corresponding to the k-th antenna element to the reception beam forming unit 23 is expressed by Expression (1).
y _Rx ^(k) (t) = c _Rx (t) • h _Tx ^(l) (t) • a _Rx • d _Rx ^(k) • h _Rx ^(k) (t) (1)
However, the antenna element corresponding to the high-frequency unit 10a is the l-th antenna element (k = l).

The reception beam forming unit 23 demodulates each Cal signal y _Rx ^(k) (t) using the Cal signal c _Rx (t) as a reference signal. The transmission / reception system calibration basic correction coefficient calculation unit 32 calculates a correlation value CR _Rx ^(k) using the Cal signal c _Rx (t) as a reference signal from each demodulated signal, using Equation (2).
CR _Rx ^(k) (t) = E [y _Rx ^(k) (t) ・ c _Rx (t) ^* ]
= h _Tx ^(l) (t) ・ a _Rx・ d _Rx ^(k)・ h _Rx ^(k) (t) (2)
However, E [] represents a time average. ^* Represents a complex conjugate.

The calibration correction coefficient calculation unit 33 holds the correlation value CR _Rx ^(k) for each antenna element as the RxCal basic correction coefficient.

Next, with reference to FIG. 3, the operation at the time of calculating the TxCal basic correction coefficient according to the present embodiment will be described. FIG. 3 shows a Cal signal transmission path (thick arrow line in the figure) at the time of calibration measurement for calculating the TxCal basic correction coefficient.
At the time of calibration measurement for calculating the TxCal basic correction coefficient, the 2-to-2 switch 12a of the high-frequency unit 10a outputs “the input signal from the HPA 16 to the coupler 11 and the input signal from the ATT 17 to the LNA 13. Set as follows. In addition, the 2-to-1 switch 12b of each high-frequency unit 10b is set to “output the input signal from the HPA 16 to the coupler 11”.

  The calibration signal generator 31 generates and outputs a Cal signal. The transmission beam forming unit 26 weights the Cal signal with “transmission array weight = Cal correction coefficient”, and outputs it to the DA converter 22 from the ports for all the high frequency units 10a and 10b. At this time, if the Cal correction coefficient has not been calculated yet, the initial value “1” of the Cal correction coefficient is used as the transmission array weight element corresponding to all the high frequency units 10a and 10b. Further, the transmission beam forming unit 26 is configured to be able to identify which high-frequency unit 10a, 10b the Cal signal is output to. For example, by using time division multiplexing or code division multiplexing, the Cal signals output to the high frequency units 10a and 10b can be distinguished from each other.

  The Cal signal output from the transmission beam forming unit 26 is output from the DA converter 22 to each of the high frequency units 10a and 10b. Thereafter, in each of the high frequency units 10a and 10b, the up converter 15, the HPA 16, the switches 12a and 12b, the coupler 11 are output. To the synthesizer / distributor 18. The synthesizer / distributor 18 synthesizes these input signals and outputs them to the ATT 17 of the high frequency unit 10a. The signal output from the ATT 17 is input to the AD converter 21 via the 2-to-2 switch 12a, the LNA 13 and the down converter 14 of the high frequency unit 10a, converted into a digital signal, and input to the reception beam forming unit 23. The Since the signal level is amplified in two stages by the HPA 16 of each high frequency unit 10b and the LNA 13 of the high frequency unit 10a, the signal level is attenuated by the ATT 17 and the signal level is adjusted.

Here, the following description will be made using variables of complex signal notation.
The Cal signal output from the transmission beam forming unit 26 for the high frequency units 10a and 10b corresponding to the k-th antenna element is defined as c _Tx ^(k) (t). Let the Cal correction coefficient corresponding to the k-th antenna element be α ^(k) (t). Let d _Tx ^(k) be the transmission characteristic of the transmission characteristic from the output of the 2-to-1 switch 12b to the combiner / distributor 18 via the coupler 11. A transmission line characteristic from the combiner / distributor 18 to the 2-to-2 switch 12a via the ATT 17 is defined as a _Tx . Regarding the transmission characteristics of the transmission system of the high-frequency units 10a and 10b corresponding to the k-th antenna element as h _Tx ^(k) (t) and the transmission characteristics of the reception system as h _Rx ^(k) (t), the above-mentioned RxCal This is the same as when calculating the basic correction coefficient.

Then, the Cal signal y _Tx ^(k) (t) input from the high-frequency units 10a and 10b corresponding to the k-th antenna element to the reception beam forming unit 23 is expressed by Expression (3).
y _Tx ^(k) (t) = c _Tx ^(k) (t) ・ α ^(k) (t) ・ h _Tx ^(k) (t) ・ d _Tx ^(k)・ a _Tx・ h _Rx ^(l) ( t) (3)
However, the antenna element corresponding to the high-frequency unit 10a is the l-th antenna element (k = l).

The reception beam forming unit 23 demodulates each Cal signal y _Tx ^(k) (t) using the Cal signal c _Tx ^(k) (t) as a reference signal. The transmission / reception system calibration basic correction coefficient calculation unit 32 calculates a correlation value CR _Tx ^(k) using the Cal signal c _Tx ^(k) (t) as a reference signal from each demodulated signal according to the equation (4).
CR _Tx ^(k) (t) = E [y _Tx ^(k) (t) ・ c _Tx ^(k) (t) ^* ]
= α ^(k) (t) ・ h _Tx ^(k) (t) ・ d _Tx ^(k)・ a _Tx・ h _Rx ^(l) (t) (4)

The calibration correction coefficient calculation unit 33 holds the correlation value CR _Tx ^(k) for each antenna element as a TxCal basic correction coefficient.

Next, a method for calculating the Cal correction coefficient from the RxCal basic correction coefficient and the TxCal basic correction coefficient will be described.
Using RxCal basic correction coefficient CR _Rx ^(k) and TxCal basic correction coefficient CR _Tx ^(k) , the transmission characteristic h _Rx ^(k) (t) of the receiving system and the transmission characteristic h _Tx ^(k) (t) of the transmitting system The ratio “h _Rx ^(k) (t) / h _Tx ^(k) (t)” is expressed by equation (5).
h _Rx ^(k) (t) / h _Tx ^(k) (t) = {CR _Rx ^(k) (t) / (h _Tx ^(l) (t) · a _Rx · d _Rx ^(k) )} / { CR _Tx ^(k) (t) / (α ^(k) (t) • d _Tx ^(k) • a _Tx • h _Rx ^(l) (t))} (5)

Here, in the case of the TDD system, since it can be considered that “a _Rx = a _Tx ” and “d _Rx ^(k) = d _Tx ^(k) ” are satisfied, the equation (5) can be transformed into the equation (6). it can.
h _Rx ^(k) (t) / h _Tx ^(k) (t) = (CR _Rx ^(k) (t) / CR _Tx ^(k) (t)) ・ (h _Rx ^(l) (t) / h _Tx ^(l) (t)) ・ α ^(k) (t) (6)

Further, since “h _Rx ^(l) (t) / h _Tx ^(l) (t)” is a coefficient common to all antenna elements, it does not affect transmission beam control. As a result, the influence of “h _Rx ^(l) (t) / h _Tx ^(l) (t)” is ignored, and “h _Rx ^(k) (t) / h _Tx ^(k) (t)” is 1. The Cal correction coefficient α ^(k) (t) for correction to be Therefore, the calibration correction coefficient calculation unit 33 calculates the Cal correction coefficient α ^(k) (t) so that Expression (7) is satisfied.
α ^(k) (t) = 1 / (CR _Rx ^(k) (t) / CR _Tx ^(k) (t))
= CR _Tx ^(k) (t)) / CR _Rx ^(k) (t) (7)

As a method for calculating the Cal correction coefficient α ^(k) (t), an optimization control technique based on the least square error method can be used. Specifically, the ratio “CR _Tx ^(k) (t) / CR _Rx ^(k) (t)” between the TxCal basic correction coefficient CR _Tx ^(k) and the RxCal basic correction coefficient CR _Rx ^(k) and the Cal correction coefficient α ^(k) The difference between (t) is defined as an error function e (t). Then, control is performed so as to minimize the square of the expected value by the equation (8).
E [| e (t) | ² ] = E [| (CR _Tx ^(k) (t) / CR _Rx ^(k) (t)) − α ^(k) (t) | ² ] (8)

According to the first embodiment described above, the transmission / reception circuit in the high frequency unit 10a can be shared during calibration measurement and during actual communication. This
It becomes possible to contribute to the apparatus cost and size reduction of the base station of a mobile communication system.

[Second Embodiment]
FIG. 4 is a block diagram showing a configuration of a wireless communication apparatus according to the second embodiment of the present invention. In FIG. 2, the same reference numerals are given to the portions corresponding to the respective portions in FIG.
In the second embodiment, as shown in FIG. 4, a high-frequency unit 10c having a 2-to-2 switch 12a is provided for all antenna elements ANT. The high frequency unit 10c is the same as the high frequency unit 10b shown in FIG. 1 except that a 2-to-2 switch 12a is provided instead of the 2-to-1 switch 12b. Further, the ATT 17 and the combiner / distributor 18 provided in the high frequency unit 10a shown in FIG. 1 are provided outside the high frequency unit 10c. Further, an n-to-1 switch 41 (n is the number of high-frequency units 10c) is provided.

  Each input / output terminal on the multi-terminal side of the n-to-1 switch 41 is one input / output terminal of the 2-to-2 switch 12a of each high-frequency unit 10c (the input / output terminal connected to the ATT 17 in FIG. 1). Equivalent). An input / output terminal on one terminal side of the n-to-1 switch 41 is connected to the ATT 17.

  The n-to-1 switch 41 is used to select the high-frequency unit 10c shared during calibration measurement and actual communication. That is, the high frequency unit 10c connected to the ATT 17 by the n-to-1 switch 41 corresponds to the high frequency unit 10a shown in FIG. 1 and is shared during calibration measurement and actual communication. The actual calibration measurement operation is the same as that of the first embodiment shown in FIG. Further, since the n-to-1 switch 41 is on a common signal path for all the high-frequency units 10c, it does not affect the calculation of the Cal correction coefficient.

  According to the second embodiment described above, all the high-frequency units 10c can support calibration measurement. Therefore, the high-frequency unit 10 c that can handle calibration measurement is not fixed, and the high-frequency unit 10 c used for calibration measurement can be arbitrarily changed by switching the n-to-1 switch 41. As a result, even if the high frequency unit 10c used for calibration measurement breaks down, it can be changed to another high frequency unit 10c simply by switching the n-to-1 switch 41. Similarly, calibration measurement can be performed. For this reason, the operation of the transmission beam control function can be ensured, and the labor required for apparatus maintenance can be reduced.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design changes and the like within a scope not departing from the gist of the present invention.

It is a block diagram which shows the structure of the radio | wireless communication apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the transmission path | route of the signal for demonstrating the operation | movement at the time of the calibration measurement concerning the embodiment. It is a figure which shows the transmission path | route of the signal for demonstrating the operation | movement at the time of the calibration measurement concerning the embodiment. It is a block diagram which shows the structure of the radio | wireless communication apparatus which concerns on 2nd Embodiment of this invention.

Explanation of symbols

10a, 10b, 10c ... high frequency section, 11 ... coupler, 12a ... 2-to-2 switch, 12b ... 2-to-1 switch, 13 ... low noise amplifier (LNA), 14 ... down converter, 15 ... up converter, DESCRIPTION OF SYMBOLS 16 ... High power amplifier (HPA), 17 ... Attenuator (ATT), 18 ... Synthesizer / distributor, 20 ... Communication baseband signal processing part, 21 ... AD converter, 22 ... DA converter, 23 ... Receive beam forming part , 24 ... reception beam control unit, 25 ... transmission beam control unit, 26 ... transmission beam forming unit, 27 ... reception unit, 28 ... transmission unit, 30 ... calibration baseband signal processing unit, 31 ... calibration signal generation 32: Transmission / reception system calibration basic correction coefficient calculation section 33: Calibration correction coefficient calculation section 41: n-to-1 switch ANT: Antenna element

Claims (4)

In a wireless communication apparatus that measures transmission characteristics of a transmission system and a reception system provided corresponding to each antenna element and corrects a difference in transmission characteristics of the transmission system and the reception system,
First switch means for switching whether a signal of the transmission system of the first antenna element is supplied to the first antenna element or distributed to the reception system of all the antenna elements;
Distributing means for distributing the signal supplied from the first switch means to the receiving systems of all the antenna elements;
Combining means for combining signals of transmission systems of all the antenna elements;
Second switch means for switching whether to supply a reception signal of the first antenna element or a signal synthesized by the synthesis means to the reception system of the first antenna element; ,
In the case of measurement of reception system characteristics, the first switch means supplies the signal of the transmission system of the first antenna element to the distribution means,
In the case of measuring transmission system characteristics, the second switch means supplies the signal synthesized by the synthesis means to the reception system of the first antenna element.
A wireless communication apparatus. Both the first and second switch means comprise a single 2-to-2 switch ;
The 2-to-2 switch outputs an input signal to the first antenna element and inputs and outputs a signal output from the first antenna element; and transmission of the first antenna element An input terminal for inputting a system signal, an output terminal for outputting a signal to be supplied to the receiving system of the first antenna element, a signal to be input to the distributing means, and a signal output from the combining means. An input / output terminal for input,
In the case of measurement of reception system characteristics, the 2-to-2 switch supplies a signal of the transmission system of the first antenna element to the distribution unit,
In the case of measurement of transmission system characteristics, the 2-to-2 switch supplies the signal synthesized by the synthesis means to the reception system of the first antenna element.
The wireless communication apparatus according to claim 1. Providing the first and second switch means for all the antenna elements;
A transmission system for supplying a signal distributed by the distribution means and a reception system for supplying a signal combined by the combining means are selected as a transmission system and a reception system for any one of the antenna elements . The switch means is further provided ,
In the case of measurement of reception system characteristics, the third switch means selects a transmission system that supplies a signal distributed by the distribution means,
In the case of measuring transmission system characteristics, the third switch means selects a reception system to which the signal synthesized by the synthesis means is supplied.
The wireless communication apparatus according to claim 1, wherein the wireless communication apparatus is a wireless communication apparatus. A calibration method for measuring transmission characteristics of a transmission system and a reception system provided corresponding to each antenna element and correcting a difference in transmission characteristics of the transmission system and the reception system,
In the case of measurement of reception system characteristics,
Switching the first antenna element transmission system signal from being supplied to the first antenna element to being distributed to all the antenna element reception systems;
Distributing the signal of the transmission system of the first antenna element to the reception system of all the antenna elements,
When measuring transmission system characteristics,
Synthesizing transmission signals of all the antenna elements;
Switching the signal supplied to the reception system of the first antenna element from the reception signal of the first antenna element to the signal synthesized by the synthesis means,
A calibration method characterized by that.

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