JP2002185375A - Adaptive array antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly update a weight of an adaptive array antenna. SOLUTION: A first reference signal is received, and a preamble of each complex OFDM signal is received. Complex weights W1 to W4 are repeatedly updated by an RLS method based on the preamble of the each complex OFDM signal and the first reference signal (step 201), and when its updating is finished, updating final values of the weights W1 to W4 are stored in a memory 118c (step 202). Then, the updating final values of the weights W1 to W4 are called from the memory 118c, a second reference signal is received, and further a pilot symbol from a pilot extractor 118a is received. Updating of the weights W1 to W4 are started by an LMS method based on the pilot symbol and the second reference signal with the updating final values of the weights W1 to W4 of the memory 118c as initial values (step 203).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an adaptive array antenna.

[0002]

2. Description of the Related Art A schematic configuration of a conventional adaptive array antenna communication device will be described with reference to FIG. 3, the array antenna communication device includes an adaptive array antenna 10 and a demodulation processing unit 20, and the adaptive array antenna includes antenna elements 1a to 1d, quasi-synchronous detectors 2a to 2d, and multipliers 3a to 3d. , An adder (Σ) 4, a weight control unit 4, and a reference signal generator 5. First, the antenna elements 1a to 1d receive received signals, respectively, and the received signals are input to the quasi-synchronous detectors 2a to 2d, respectively. However, the received signal contains a desired known signal. The quasi-synchronous detectors 2a to 2d respectively perform quasi-synchronous detection (quadrature detection) on the input received signal.
And outputs a complex reception signal.

Next, a multiplier 3a multiplies the complex reception signal from the quasi-synchronous detector 2a by a complex weight W1 to obtain a first signal.
The multiplier 3b multiplies the complex received signal from the quasi-synchronous detector 2b by the complex weight W2 to obtain a second multiplied signal. The multiplier 3c multiplies the complex reception signal from the quasi-synchronous detector 2c by the complex weight W3 to obtain a third signal.
The multiplier 3d multiplies the complex reception signal from the quasi-synchronous detector 2d by the complex weight W4 to obtain a fourth signal.
Is obtained. The adder (Σ) 4 adds the first to fourth multiplication signals of the multipliers 3 a to 3 d to obtain an addition signal, and outputs the addition signal to the demodulation processing unit 6.

Here, the complex control signals from the quasi-synchronous detectors 2a to 2d and the reference signal (desired known signal) from the reference signal generator 6 are input to the weight control unit 5, and the weight control unit 5 Calculates the same addition signal as the addition signal of the adder 4 (hereinafter referred to as an operation addition signal) by performing arithmetic processing based on each complex reception signal of the quasi-synchronous detectors 2a to 2d. Further, the weight control unit 5 updates the complex weights W1 to W4 so that the operation addition signal approaches the reference signal (desired known signal). Thereby, the addition signal from the adder (Σ) 4 is a signal in which components other than the reference signal (desired known signal) among the complex reception signals of the quasi-synchronous detectors 2a to 2d are suppressed.

[0005]

By the way, the present inventors have proposed a communication system using an orthogonal multicarrier system.
The application of the above-described adaptive array antenna communication device was studied. As shown in FIG. 4, a preamble signal (known OFDM signal) is used prior to a data signal (data OFDM signal) as an orthogonal multicarrier signal (hereinafter, referred to as an OFDM signal). Specifically, the format of the OFDM signal is configured as shown in FIG.

In FIG. 5, the vertical direction indicates the time direction (symbol), and the horizontal direction indicates the frequency direction (carrier). The white circles in the figure are data symbols (information signals),
The black circles are pilot symbols (known signals). As can be seen from FIG. 5, the preamble signal is represented on the frequency axis by
This is a signal in which only a plurality of pilot symbols are arranged. This preamble signal is used for performing initial synchronization on the communication terminal side. Further, the data signal is composed of a plurality of data symbols and pilot symbols arranged between the plurality of data symbols.
That is, the data signal includes a plurality of data symbols arranged on the frequency axis and a pilot symbol arranged between the plurality of data symbols. This pilot symbol is used for performing channel estimation and correction on the communication terminal side.

According to the study of the present inventors, when an OFDM signal is received by an adaptive array antenna, a pilot symbol is extracted from the data signal when the OFDM signal data signal is received. We thought that we needed to update the complex weights based on the pilot symbols. On the other hand, when a preamble signal of an OFDM signal is received, the preamble signal is composed of only a plurality of pilot symbols, and therefore, without extracting pilot symbols from the preamble signal,
It is conceivable to adopt this preamble signal as a signal on the time axis to update the complex weight. For this reason,
In updating the complex weight, different reference signals are required when receiving the data signal of the OFDM signal and when receiving the preamble signal of the OFDM signal. As described above, when only one reference signal is used, O
There is a problem that it becomes difficult to update the complex weight in receiving the FDM signal.

In view of the above, it is an object of the present invention to provide an adaptive array antenna capable of favorably updating weights even when two different signals are received at different times.

[0009]

According to the present invention, in order to achieve the above object, according to the first aspect of the present invention, a first reception signal is received and a second reception signal is received after the reception. A plurality of antenna elements (101-104)
Each first received signal received by the plurality of antenna elements is multiplied by a first weight, and each first received signal multiplied by the first weight is added to form a first added signal. And the first addition signal and the first
A first updating means (201) for updating the first weight according to the reference signal, and a second weight multiplied by each second received signal received by the plurality of antenna elements. Each second multiplied by a second weight
A second updating means (203) for obtaining a second added signal by adding the received signals and updating the second weight according to the second added signal and the second reference signal.
And characterized in that:

As described above, by using the first and second reference signals, the first updating means updates the first weight according to the first addition signal and the first reference signal. , Second
Updating means updates the second weight according to the second addition signal and the second reference signal. Therefore, the first and second
The weight can be satisfactorily updated even when two different signals, such as the received signal of FIG.

Further, according to the present invention, a known OFDM signal in which only known signals are arranged on the frequency axis is received, and after this reception, the known signal and the information signal are arranged on the frequency axis. And a plurality of antenna elements (101 to 104) for receiving the received data OFDM signals, and multiplying each known OFDM signal received by the plurality of antenna elements by a first weight, and multiplying the first weight by the first weight. A first updating means (202) for adding a known OFDM signal to obtain a first added signal, and updating a first weight according to the first added signal and the first reference signal; Extracting means (118a) for extracting a known signal from each of the data OFDM signals received by the plurality of antenna elements; The second known signal multiplied by the second weight is added to obtain a second addition signal, and a second addition signal is obtained according to the second addition signal and the second desired known signal. And a second updating unit (203) for updating the weight.

As described above, by employing the first and second reference signals, the first updating means updates the first weight according to the first addition signal and the first reference signal. , Second
Updating means updates the second weight according to the second addition signal and the second reference signal. Therefore, the known OFDM
Even when two different signals such as a signal and a data OFDM signal are received at different times, the weight can be updated favorably as in the first aspect of the present invention.

The first updating means obtains a first addition signal by using a known OFDM signal on a time axis without using a known signal of the known OFDM signals.
The first weight is updated by using the addition signal of (1). Therefore, according to the second aspect of the present invention, a known signal is extracted from the known OFDM signal, and the first signal is extracted using the known signal.
The update of the first weight can be speeded up as compared with the case where the weight is updated.

According to the third aspect of the present invention, when the updating of the first weight by the first updating means is completed, the first weight has holding means (202, 118c) for holding the first weight, and the second weight has the second weight. Updating means sets the held first weight as an initial value of the second weight. Thereby, the second updating unit updates the held first weight with
Since the initial value of the second weight is set, the convergence speed of the update of the second weight can be improved as compared with the case where a random value is adopted as the initial value of the second weight.
Here, as in the invention according to claim 4, the updating method for updating the first weight by the first updating means includes an updating method for updating the second weight by the second updating means. You may make it different.

[0015]

FIG. 1 shows an embodiment of an adaptive array antenna receiving apparatus according to the present invention. In the present embodiment, an example is shown in which the adaptive array antenna receiver is applied to a communication system using the OFDM signal format shown in FIGS. FIG. 1 is a block diagram showing an electrical configuration of the adaptive array antenna receiving device. In addition, the adaptive array antenna receiving apparatus is applied to a base station of an OFDM communication system.

As shown in FIG. 1, the array antenna receiving apparatus is composed of an adaptive array antenna 100 and a demodulation processing unit 120.
0 is the antenna elements 101 to 104, the quasi-synchronous detector 10
5 to 108, multipliers 109 to 112, adder (Σ) 11
3. System control unit 114, changeover switch 115, generator 1
16, 117, weight control section 118, FFT circuit 130-
133 and a timing detector 134. The antenna elements 101 to 104 respectively receive the OFDM signal, and the received OFDM signals are input to the quasi-synchronous detectors 105 to 108, respectively.
Numerals 05 to 108 output a complex OFDM signal by performing quasi-synchronous detection (orthogonal detection) on the input OFDM signal.

The FFT circuit 130 includes a quasi-synchronous detector 105
A pilot symbol (known signal) and a data symbol (information signal) are extracted from the data signal by performing FFT processing based on the complex OFDM signal data signal (see FIG. 4). However, the FFT circuit 130 is prohibited from performing the FFT processing on the preamble signal of the complex OFDM signal by a command from the method control unit 114.
When a preamble signal of a complex OFDM signal is input, the FFT circuit 130 outputs a preamble signal of the complex OFDM signal.

The FFT circuit 131 is connected to the quasi-synchronous detector 106
FFT based on the data signal of the complex OFDM signal from
By processing, pilot symbols and data symbols are extracted from the data signal. However, FFT
The circuit 131 receives a command from the system control unit 114,
Since the FFT processing of the preamble signal is prohibited,
When a preamble signal is input, the FFT circuit 131 outputs a preamble signal of the complex OFDM signal.

The FFT circuit 132 has a complex OFD signal from the quasi-synchronous detector 107 substantially similar to the FFT circuit 130.
FFT processing is performed based on the data signal of the M signal to extract pilot symbols and data symbols from the data signal. However, the FFT circuit 132, when substantially the same as the FFT circuit 130, receives a complex OF signal when a preamble signal is input by a command from the system control unit 114.
The preamble signal of the DM signal is output.

The FFT circuit 133 has a complex OFD signal from the quasi-synchronous detector 108 substantially similar to the FFT circuit 130.
FFT processing is performed based on the data signal of the M signal to extract pilot symbols and data symbols from the data signal. However, substantially similar to the FFT circuit 130, when a preamble signal is input by a command from the system control unit 114, the FFT circuit 133
The preamble signal of the DM signal is output.

Multiplier 109 multiplies the output signal of FFT circuit 130 by complex weight W1 to output a first multiplied signal. Specifically, the multiplier 109 includes the FFT circuit 1
30. The preamble signal from 30 is multiplied by the complex weight W1, and the multiplication result is output as a first multiplication signal. Multiplier 109 multiplies the pilot symbol of FFT circuit 130 by complex weight W1 and outputs the multiplication result as a first multiplication signal.
Is multiplied by the complex weight W1 and the result of the multiplication is output as a first multiplication signal.

Multiplier 110 multiplies the output signal of FFT circuit 131 by complex weight W2 to output a second multiplied signal. Specifically, the multiplier 110 includes the FFT circuit 1
The preamble signal from P.31 is multiplied by the complex weight W2, and the multiplication result is output as a second multiplication signal. Multiplier 110 multiplies the pilot symbol of FFT circuit 131 by complex weight W2 and outputs the result of the multiplication as a second multiplied signal.
Is multiplied by the complex weight W2, and the result of the multiplication is output as a second multiplication signal.

Multiplier 111 adds complex weight W to the output signal of FFT circuit 132 in substantially the same manner as multiplier 109.
3 to output a third multiplied signal.
Is substantially similar to the multiplier 109,
Is multiplied by the complex weight W4 to output a fourth multiplied signal. Further, the adder 113 adds the first to fourth multiplication signals of the multipliers 109 to 112 and outputs an addition signal to the demodulation processing unit 120. The demodulation processing unit 120 converts the addition signal into To perform demodulation processing.

Receiving the signal indicating the end of reception of the preamble signal by timing detector 134, system control section 114 receives FFT circuits 130 to 133 and weight control section 11
8 and a command to the changeover switch 115. The changeover switch 115 receives a command from the method control unit 114 and switches and connects one of the reference signal generators 116 and 117 to the weight control unit 118. Specifically, the changeover switch 115 connects between the reference signal generator 116 and the weight control unit 118 when receiving the preamble signal, while the changeover switch 115 operates when receiving the data signal.
The reference signal generator 117 and the weight control unit 118 are connected.

The generator 116 pre-stores a preamble signal on the time axis as a first reference signal, and the generator 116 outputs the first reference signal to the weight controller 118 through the changeover switch 115. On the other hand, the generator 117
Stores the pilot symbol of the data signal in advance as a second reference signal, and the generator 117
Of the weight control unit 1 through the switch 115
18 is output. Further, based on the complex OFDM signals from the quasi-synchronous detectors 105 to 108, the timing detector 134 detects a start timing at the start of receiving a data signal among the complex OFDM signals.

It should be noted that the timing detector 134
The complex preamble signal on the time axis is stored in advance,
The stored complex preamble signal and the quasi-synchronous detector 1
By performing correlation detection with the complex OFDM signals from 05 to 108, the end of the reception of the preamble signal of the complex OFDM signal and the start of the reception of the data signal of the complex OFDM signal are detected.

The weight control unit 118 includes the quasi-synchronous detector 10
Each of the complex OFDM signals 5 to 108 and the system control unit 114
And the first and second reference signals of the generators 116 and 117. The weight control unit 118 controls each complex OFDM
The complex weights W1 to W4 are updated and output to the multipliers 109 to 112 according to the signal, the instruction from the scheme control unit 114, and the first and second reference signals. Specifically, the weight control unit 118 includes a pilot extraction unit 118a together with the calculation unit 118b. The pilot extraction unit 118a receives a data signal of each complex OFDM signal according to a command from the system control unit 114. FFT processing is performed on the data of each complex OFDM signal.

Specifically, the pilot extracting section 118a
Extracts a pilot symbol from the data signal of the complex OFDM signal from the quasi-synchronous detector 105 and outputs the extracted pilot symbol as a first pilot symbol.
The pilot symbol is extracted from the data signal of the complex OFDM signal from No. 6 and output as the second pilot symbol. Further, pilot extracting section 118a extracts a pilot symbol from the data signal of the complex OFDM signal from quasi-synchronous detector 107 and outputs the extracted pilot symbol as a third pilot symbol, while outputting the complex OFDM signal from quasi-synchronous detector 108. A pilot symbol is extracted from the data signal and output as a fourth pilot symbol.

The operation unit 118b is provided for the pilot extraction unit 11
8a, the first to fourth pilot symbols from each complex O
The complex weights W1 to W4 are updated according to the preamble signal of the FDM signal and the first and second reference signals.
Here, prior to the description of the operation of the arithmetic unit 118b, an updating method for updating the complex weight (weight) will be described. In the present embodiment, in order to obtain a complex weight, M
LMS (Lea) of the MSE (Minimum Mean Square Error) method
st Mean Square algorithm), RLS (Recursive Leas)
t Squares algorithm).

First, the addition signal (complex output signal of the array element) of the adder 113 at time t is defined as y (t), and x
n (t) and wn (t) are the n-th (in this embodiment, 1 ≦
n ≦ 4) represents a complex input signal and a complex weight in an antenna element. However, when the data signal of each complex OFDM signal is received, the complex input signal
A pilot symbol of the data signal of the FDM signal is employed. On the other hand, when the preamble of each complex OFDM signal is received, each complex OFD signal is
A preamble signal of M signal is employed.

Here, xn (t), wn
(T) (n = 1, 2,... 4) are input vector X
(T) and expressed as Equations 1 and 2 in the form of a weight vector W (t).

[0032]

X (t) = [x1 (t), x2 (t),... X4
(T)]

[0033]

W (t) = [y1 (t), y2 (t),... Y4
(T)] The addition signal y (t) is obtained by using Expressions 1 and 2 and Expression 3
Can be expressed as Here, H represents the complex transposition.

[0034]

Y (t) = X (t) ^H · W (t) = X (t) ·
W (t) ^H and the error signal e (t) are a reference signal (first and second reference signals) d (t), which is a desired array response, and a sum signal (actual array output) of the adder 113. Signal) y (t)
And given by Equation 4.

[0035]

## EQU4 ## e (t) = d (t) -y (t) = d (t) -W
(T) ^H・ X (t) The purpose of the MMSE method is to minimize the expected value of the square of the error signal e (t) (mean square error), E {| e (t) | ² }. . (LMS method) An optimal algorithm based on the LMS method is represented by Expression 5.

[0036]

(Equation 5)

Here, m responds to a sampling time represented by t = mT (T is a sampling interval), and μ is a step size. By rearranging Equation 5 except for the unsampled time averaging operation, Equation 6 is obtained. In the LMS method, the complex weight is updated based on Equation 6.

[0038]

(Equation 6)

(RLS Method) In the RLS method, the square of the exponential weighted error as shown in Expression 7 is directly minimized using all input samples up to the present time.

[0040]

(Equation 7)

Here, α is a weighting constant of 0 <α <1. A least-squares solution can be obtained by setting the gradient vector for W in Equation 6 to zero, but here, first, an input correlation matrix is estimated and a complex weight is obtained by the sequential method as follows.

[0042]

(Equation 8)

[0043]

(Equation 9)

Here, δ is a constant integer. At this time, the update equation of the complex weight is expressed as in Expression 10.

[0045]

(Equation 10)

Here, γ is given by Expression 11.

[0047]

[Equation 11]

Hereinafter, the operation unit 118b of the weight control unit 118
Will be described with reference to FIG. First, the operation unit 1
The memory 118c of the memory 18b is initialized (step 20).
0), when it is determined that the antenna elements 101 to 104 have received the preamble signal of the OFDM signal by a command from the method control unit 114, the process proceeds to step 201.
The complex weights W1 to W4 at the time of receiving the preamble signal of the OFDM signal are updated based on the RLS method described above, and the complex weights W1 to W4 are multiplied by the multiplier 1
Output to 09-112.

More specifically, the first reference signal is received from the generator 116 through the changeover switch 115, and the complex OFDM signals from the quasi-synchronous detectors 105 to 108 are received.
Receive the preamble signal of the signal. Quasi-synchronous detector 105
Is multiplied by a complex weight W1 to obtain a first multiplied signal. Ask for.
The preamble signal of the complex OFDM signal from the quasi-synchronous detector 107 is multiplied by the complex weight W3 to obtain a third multiplied signal, and the preamble signal of the complex OFDM signal from the quasi-synchronous detector 108 is multiplied by the complex weight W4. A fourth multiplied signal is obtained.

Further, a first addition signal is obtained by adding the first to fourth multiplication signals, and a complex weight is set so that the first addition signal approaches a first reference signal (a preamble signal on a time axis). Update W1 to W4. At the same time, the complex weight W1 is output to the multiplier 109, and the complex weight W is output.
2 is output to the multiplier 110, the complex weight W3 is output to the multiplier 111, and the complex weight W4 is output to the multiplier 112. Next, according to a command from the system control unit 114,
If it is determined that the reception of the preamble signal of the OFDM signal by the antenna elements 101 to 104 is completed, the process proceeds to step 202, and the updated final values of the complex weights W1 to W4 by the preamble signal are stored in the memory 118c.

Next, when it is determined that the reception of the data signal of the OFDM signal by the antenna elements 101 to 104 is started by a command from the system control unit 114, the process proceeds to step 203, where the data signal of the OFDM signal is The update processing of the complex weights W1 to W4 according to is started. First, the updated final values of the complex weights W1 to W4 are called from the memory 118c, and the updated final values of the complex weights W1 to W4 are called multipliers 109 to 11, respectively.
Output to 2.

Here, the change-over switch 1
15 to receive the first to fourth pilot symbols from the pilot extractor 118a. Further, the first pilot symbol is multiplied by the updated final value of the complex weight W1 to obtain a first pilot multiplied signal, and the complex weight W2 is added to the second pilot symbol.
To obtain a second pilot multiplied signal. The third pilot symbol is multiplied by the updated final value of the complex weight W3 to obtain a third pilot multiplied signal, and the fourth pilot symbol is multiplied by the updated final value of the complex weight W4 to obtain a fourth pilot multiplied signal. Ask. Here, the first to fourth fourth pilot multiplied signals are added to obtain a second added signal.

Then, the complex weights W1 to W4 are updated so that the second addition signal approaches the second reference signal, and output to the multipliers 109 to 112. As described above, the updated final values of the complex weights W1 to W4 are used as the initial values for updating the complex weights W1 to W4 in the data signal of the OFDM signal. Thereafter, the updated complex weights W1 to W4 (hereinafter, updated complex weights W1 to W4)
4), a second reference signal from generator 117,
The complex weights W1 to W4 are sequentially updated with the first to fourth pilot symbols from the pilot extractor 118a and output to the multipliers 109 to 112.

More specifically, the first pilot symbol is multiplied by an updated complex weight W1 to obtain a first pilot multiplied signal, and the second pilot symbol is multiplied by an updated complex weight W2 to obtain a second pilot multiplied signal. Find the signal. The updated complex weight W3 is added to the third pilot symbol.
To obtain a third pilot multiplied signal, and multiply the fourth pilot symbol by the updated complex weight W4 to obtain a fourth pilot multiplied signal. Here, first to fourth
To obtain a second addition signal. Furthermore, the complex weights W1 to W4 are updated so that the second addition signal approaches the second reference signal, and output to the multipliers 109 to 112. Thereafter, when the reception of the data signal of the OFDM signal ends, the updated complex weights W1 to W1 are output.
The updating of W4 is stopped (step 204).

Hereinafter, features of the present embodiment will be described. First,
When the first reference signal is prepared in advance and the preamble signal of the OFDM signal is being received, the complex weights W1 to W1 are set so that the first addition signal approaches the first reference signal.
Update W4. Further, when the second reference signal is prepared in advance and the data signal of the OFDM signal is received, the complex weights W1 to W4 are updated so that the second addition signal approaches the first reference signal. As described above, since the complex weights W1 to W4 are updated, even if the preamble signal and the data signal of the OFDM signal are received before and after the time, the complex weights W1 to W4 can be updated favorably.

When the reception of the data signal of the OFDM signal is started, the updated final values of the complex weights W1 to W4 in the preamble signal are called from the memory 118c, and the updated final values of the called complex weights W1 to W4 are read. Since the updating of the complex weights W1 to W4 is started as the initial value, the convergence of the updating of the complex weights W1 to W4 is faster than in the case of using a random value as the initial value.
Stability is obtained.

Further, when the preamble signal of the OFDM signal is being received, the complex weights W1 to W based on the preamble signal have not been subjected to the FFT processing.
4 can be updated faster. That is, a longer update processing time is required when a data signal is being received than when a preamble signal is being received.

Generally, the algorithm of the LMS method is RL
Compared with the S method algorithm, the signal processing amount is small and the processing time is short. Therefore, in the present embodiment, as described above,
When a preamble signal is being received, complex weights W1 to W4 are calculated using an algorithm based on the RLS method.
While the data signal is being received, the complex weights W1 to W4 are updated using an algorithm based on the LMS method. As a result, the processing time can be balanced between the reception of the preamble signal and the reception of the data signal.

In implementing the present invention, any adaptive array antenna communication apparatus that receives two different signals before and after may be applied to various signals other than the OFDM signal.

Further, in the above embodiment, when updating the complex weights W1 to W4, an algorithm based on the RLS method is used when a preamble signal is received, while an LMS method is used when a data signal is received. Although the example using the algorithm based on was explained,
However, the present invention is not limited to this, and the same algorithm may be adopted when a preamble signal is received and when a data signal is received, or an algorithm other than the LMS method and the RLS method may be adopted. Good.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an adaptive array antenna communication device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the embodiment.

FIG. 3 is a block diagram illustrating a configuration of a conventional adaptive array antenna communication device.

FIG. 4 is a diagram showing an OFDM signal.

FIG. 5 is a diagram showing a format of an OFDM signal.

[Explanation of symbols]

100: adaptive array antenna, 118: weight control unit, 118b: arithmetic unit, 118c: memory, W1 to W4
... complex weight.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takenori Matsue 14 Iwatani, Shimowasumi-cho, Nishio-shi, Aichi Prefecture Inside Japan Automotive Parts Research Institute (72) Inventor Akira Inoue 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Shares In Company Denso (72) Inventor Shigeru Kadota 1-1-1 Showa-cho, Kariya-shi, Aichi F-term in Denso Corporation (Reference) 5J021 AA05 AA06 CA06 DB02 DB03 DB04 EA04 FA14 FA15 FA16 FA17 FA20 FA29 FA30 FA31 FA32 5K059 CC09 DD31 EE02 5K067 AA14 CC24 KK03

Claims (4)

[Claims] 1. A plurality of antenna elements (101-104) for receiving a first received signal and receiving a second received signal after the first received signal, and each of the first antenna elements received by the plurality of antenna elements. Is multiplied by a first weight, and the respective first received signals multiplied by the first weight are added to obtain a first added signal, and the first added signal and the first added signal are obtained. First updating means (201) for updating the first weight in accordance with the reference signal of (c), and multiplying each of the second received signals received by the plurality of antenna elements by a second weight; The respective second received signals multiplied by the second weight are added to obtain a second added signal, and the second weight is calculated according to the second added signal and the second reference signal. Second update to update Adaptive array antenna characterized in that it comprises a stage (203), the. 2. Receiving a known OFDM signal in which only known signals are arranged on a frequency axis, and after this reception,
A plurality of antenna elements (101 to 101) for receiving a data OFDM signal in which a known signal and an information signal are arranged on a frequency axis.
104); and the respective known Os received by the plurality of antenna elements.
The FDM signal is multiplied by a first weight, the respective known OFDM signals multiplied by the first weight are added to obtain a first addition signal, and the first addition signal and the first reference signal are obtained. First updating means (202) for updating the first weight in accordance with the above, and extracting means (11) for extracting a known signal from the respective data OFDM signals received by the plurality of antenna elements.
8a), multiplying each of the extracted known signals by a second weight, and adding each of the known signals multiplied by the second weight to obtain a second addition signal; And a second updating unit (203) for updating the second weight according to the addition signal and the second desired known signal. 3. When the updating of the first weight by the first updating unit is completed, the first updating unit includes a holding unit (202, 118c) for holding the first weight, and the second updating unit. 3. The adaptive array antenna according to claim 1, wherein the first weight is set as an initial value of the second weight. 4. An updating method for updating said first weight by said first updating means is different from an updating method for updating said second weight by said second updating means. The adaptive array antenna according to any one of claims 1 to 3.