JP2001223624A - Radio receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio receiver that can satisfactorily receive a broadband multi-carrier signal by using an adaptive array antenna. SOLUTION: A transmitter side transmits a multi-carrier signal to each carrier of which a known signal is set. Antennas 1 of the receiver receive the multi-carrier signal, and an analog/digital converter 2 applies analog/digital conversion to the multi-carrier signal and a weight multiplier 3 multiplies weight with the analog/digital converted multi-carrier signal. An adder 4 sums outputs of the weight multipliers 3 and a weight control section 5, which is compatible with the multi-carrier signal uses the composite signal and a replica of the known signal in the multi-carrier signal to update the weight, so as to apply beam control to the adaptive array antenna. Thus, the receiver separates/ composites the arrival paths.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiving apparatus for receiving a multi-carrier signal for performing signal transmission using a plurality of carriers, and more particularly, to a radio receiving apparatus for receiving and combining signals using a plurality of antennas. It concerns the device.

[0002]

2. Description of the Related Art Conventionally, in wireless communication, a single carrier transmission system for transmitting a signal using a single frequency has been often used. Further, in order to receive a signal with good quality in a receiver, a signal receiving method of receiving and combining signals using a plurality of antennas has been often used. Among them, an adaptive array using a directional beam is known as a method capable of obtaining a desired desired signal receiving characteristic by directing a beam to a desired signal and suppressing a beam in an interference signal direction.

FIG. 15 is a diagram showing a configuration of a conventional adaptive array for receiving a single carrier signal. In the figure, 1 is an antenna, 2 is an A / D converter, 3 is a weight multiplier, 4
Denotes an adder, 70 denotes a weight control unit, and 71 denotes a signal demodulation unit. As shown in this figure, a plurality of antennas 1 constituting an array antenna are provided, and for each antenna 1, an A / D converter 2 for converting the output to a digital signal and the A / D conversion output Is provided with a weight multiplier 3 for multiplying each by a weight (weight). The outputs of the weight multipliers 3 are combined by the adder 4 and input to the weight control unit 70. The weight control unit 70 determines the weight by which each of the weight multipliers 3 multiplies the received signal so that the beam pattern of the array by the plurality of antennas 1 becomes an optimal beam pattern.

FIG. 16 shows a transmission signal format. In the figure, reference numeral 72 denotes a frame, 73 denotes a known signal, and 74 denotes an information signal. FIG. 17 is a flowchart showing a procedure of weight control in the adaptive array. FIG.
Represents a beam pattern when an adaptive array is used, 75 to 77 represent multipath signals, and 78 represents a beam pattern.

Hereinafter, a conventional adaptive array will be described with reference to FIGS. First, as shown in the format of FIG. 16, the signal is transmitted as a known signal 73 and an information signal 74 separately in time. After setting the initial weight (step S301 in FIG. 17), the receiver receives these signals using the plurality of antennas 1 shown in FIG. 15 (S302). Next, after the A / D converter 2 A / D converts the received signal of each antenna 1, the weight multiplier 3 performs weight multiplication on the received signal from each antenna (S303). The received signals from the antennas 1 multiplied by the weights are added and combined in the adder 4 (S304). The synthesized signal is input to the weight control unit 70, and calculation is performed according to a predetermined algorithm (S305). After the calculation, the weight control unit 70 outputs an update weight, and the weight multiplier 3 updates the weight multiplied by the received signal (S307). After the weight update is performed,
A series of processes from step S303 is performed again.

Generally, the weight control unit 70 measures an error between a known signal in a combined signal and a known signal replica of a receiving station, and generally determines a weight so as to reduce the error by a weight determination algorithm. Used. In particular, as an algorithm for minimizing the square error between a received known signal and a known signal replica, LMS (LeastMea
n Square) method, RLS (Recursive Least Squares)
The SMI (Sample Matrix Inverse) method and the like are known. For example, in the case of the LMS method, the weight is updated according to the following equation. Δw = k · E [X · ε] where w is a weight vector representing the weight of each antenna in a vector format, Δw is the weight update width of each antenna, k is a constant, and X is the signal strength of each antenna. A signal vector expressed in the form, ε represents an error between the synthesized signal and the known signal replica, and E [•] represents a time average. When the error ε between the combined signal and the reference signal (known signal replica) becomes equal to or less than a predetermined level, the weight control unit 70 determines that the weight has sufficiently converged, and ends the weight update processing (S206). Then, a signal demodulation unit 71 demodulates the signal of the output of the adaptive array.

As described above, when the determined weight is used, the beam pattern formed by the plurality of antennas 1 becomes, for example, a pattern shown by 78 in FIG. In this figure, the arrival paths 75 and 76 are when the delay time is within the symbol time T of the known signal, and in this case, the paths are combined in phase. In addition, it is assumed that the delay time of the arrival path 77 is longer than the symbol time T of the known signal with respect to the arrival path 75. in this case,
The reception level of the arrival path 77 is suppressed. As described above, by combining the multipaths using the adaptive array antenna, it is possible to secure good reception signal characteristics.

[0008]

Recently, in wireless communication,
There is an increasing demand for a system capable of higher-speed transmission and higher-speed movement, and it is necessary to transmit a wide-band signal in a radio frequency band. Regarding the transmission of wideband signals, a multi-carrier transmission scheme for performing parallel transmission of signals using a plurality of carriers simultaneously has attracted particular attention recently. In the multi-carrier transmission method, low-speed data is arranged in parallel on a frequency and transmitted simultaneously using different carriers.
The transmission speed is improved by performing signal parallel transmission.

This multi-carrier transmission system has a feature that it is resistant to transmission delay of an incoming path and can perform good transmission even in a frequency selective fading environment where the fluctuation characteristics of a received signal vary with frequency. On the other hand, since the frequency band of each carrier transmitted in parallel is small, when the Doppler frequency of the incoming path is large, it also has the disadvantage of adversely affecting other adjacent transmission carriers. Therefore, an adaptive array technique for extracting and combining incoming paths having a predetermined transmission delay and a predetermined Doppler frequency from the incoming paths has been a problem. However, at present, no technique has been proposed for applying an adaptive array antenna to such a wideband multicarrier signal. The conventional adaptive array basically targets a single carrier signal using a single frequency, and does not assume a configuration of an adaptive array antenna for a multicarrier signal. As described above, it is required to clearly show a configuration of an adaptive array that enables separation / combination of incoming paths for a wideband multicarrier signal. Also,
In order to suppress the ill effect of an incoming path having a large Doppler frequency on a received signal, an adaptive array technique for suppressing an incoming path having a large Doppler frequency has been a challenge.

[0010] Therefore, an object of the present invention is to provide a signal receiving apparatus using an adaptive array antenna in a wideband multicarrier transmission system. Also,
It is an object of the present invention to provide a signal receiving device capable of separating and combining incoming paths when receiving a wideband multicarrier signal. It is another object of the present invention to provide a signal receiving apparatus using an adaptive array antenna that can suppress an incoming path having a large Doppler frequency.

[0011]

To achieve the above object, a radio receiving apparatus according to the present invention comprises a plurality of antennas and a plurality of weight multipliers for multiplying a reception signal from each corresponding antenna by a predetermined weight. And a combining unit that combines the outputs of the weight multipliers, and a weight control that determines the weight using a received signal corresponding to a known signal transmitted from a plurality of carriers output from the combining unit and transmitted. And a part. Further, the known signal has the same frequency band as the information signal. Further, the weight control unit is configured to minimize a square error between a received signal corresponding to the known signal arranged and transmitted on the plurality of carriers and a replica of the known signal arranged on the plurality of carriers. It uses a decision algorithm.

Further, another radio receiving apparatus of the present invention comprises a plurality of antennas, a plurality of weight multipliers for multiplying a reception signal from each corresponding antenna by a predetermined weight, and an output of each weight multiplier. A synthesis unit that synthesizes
A multi-carrier demodulation unit that performs multi-carrier demodulation on the combined signal from the combining unit; and a weight control unit that determines the weight using the demodulated signal from the multi-carrier demodulation unit. Still further, the weight control unit determines the weight using a demodulated signal corresponding to a known signal transmitted by being allocated to a plurality of carriers. Furthermore, the known signal is arranged on a carrier having a predetermined frequency interval, or is always arranged on a specific carrier.

Still another radio receiving apparatus of the present invention comprises a plurality of antennas, a plurality of weight multipliers for multiplying a received signal from each corresponding antenna by a predetermined weight, and a plurality of weight multipliers. A radio receiving apparatus comprising: a combining unit that combines outputs of the weighting unit; a multicarrier demodulation unit that performs multicarrier demodulation on a combined signal from the combining unit; and a weight control unit that determines the weight. The controller, in an initial stage of the communication, determines the weight using a received signal corresponding to a known signal transmitted by being arranged on a first predetermined number of carriers output from the combining unit, and thereafter, In the communication step, a demodulated signal of the multicarrier demodulation unit corresponding to a known signal arranged on a second predetermined number of carriers smaller than the first predetermined number Are those configured to determine the weights used.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a basic configuration of a first embodiment of the signal receiving apparatus of the present invention. In the figure, 1 is an antenna, 2 is an A / D converter, 3 is a weight multiplier, 4 is an adder, 5 is a weight control unit corresponding to a multicarrier signal, and 6 is a multicarrier signal demodulation unit. FIG. 2 is a diagram showing a transmission signal format, in which 7 to 9 are multicarrier signals,
10 is a frame, 11 is a known multicarrier signal, 12
Represents a multicarrier information signal. FIG. 3 is a diagram illustrating a transmission waveform of a multicarrier known signal, and FIG. 4 is a flowchart illustrating a weight control procedure of an adaptive array. FIG. 5 illustrates an example of a beam pattern when the adaptive array according to the present embodiment is used.
8 to 20 indicate multipath signals, and 21 indicates a beam pattern.

First, the format of a multicarrier signal transmitted using FIG. 2 will be described. In the figure, the vertical direction indicates the frequency, and the horizontal direction indicates the time axis. As shown in the figure, in the multicarrier signal, a plurality of carriers 7 to 9 including a first carrier 7 (frequency # 1), a second carrier 8 (frequency # 2), a third carrier 9 (frequency # 3). The signal is transmitted using. In each of the carriers 7 to 9, data is temporally arranged, and the data in each of the carriers 7 to 9 is temporally synchronized. In the present invention, each frame 10 of the transmission data is divided into a known signal 11 and an information signal 12, and the known signal 11 is used for adaptive array beam control. This known signal 11 is inserted at the same time in each carrier. FIG. 3 is a diagram showing a time waveform of a multicarrier known signal at the time of multicarrier transmission, and a transmission waveform 17 is given by the sum of known signals 13 to 16 on each carrier of frequencies # 1 to # 4.
As shown in this figure, unlike the known signal in the conventional method, the transmission waveform 17 has different power in time in multicarrier transmission.

The adaptive array according to the present embodiment will be described below with reference to FIGS. First, in the signal receiving device, after setting an initial weight in the weight multiplier 3 (S101 in FIG. 4), a multicarrier signal is received using the plurality of antennas 1 shown in FIG. 1 (S102). . Next, the A / D converter 2 converts the A / D of each signal.
After the D conversion, each weight multiplier 3 performs weight multiplication on the input signal from each antenna 1 using the set initial weight (S103). Next, the received signals of each antenna multiplied by the weight are added and combined in the adder 4 (S104). The combined signal is input to the multi-carrier weight controller 5, and a calculation is performed to obtain an optimal weight according to a predetermined algorithm using a known signal replica (S105).
After the calculation is performed, the multi-carrier weight controller 5 outputs the corresponding update weight to each of the weight multipliers 3 and updates the weight (S10).
7). After the weight is updated, step S10 is performed again.
3 are repeated until the error between the synthesized signal and the known signal replica becomes equal to or less than a predetermined level.

The weight control unit 5 corresponding to the multi-carrier.
In this method, the square error between the received known signal and the known signal replica is measured, and the weight is determined so as to reduce the square error. This method includes the LMS method and the R
An LS method, an SMI method, or the like can be used. For example,
When the LMS method is used, the weight is updated according to the following equation. Δw = k · E [X · ε] where w is a weight vector representing the weight of each antenna for the received signal in vector format, Δw is the weight update amount for the received signal of each antenna, k is a constant,
X is a signal vector representing the signal strength of the multicarrier known signal in each antenna in a vector format, ε is the error between the composite signal of the multicarrier known signal and the multicarrier known signal replica, and E [•] is the time average. In addition,
The signal strength of the multicarrier known signal can be obtained by taking the correlation between the received signal at each antenna and the known signal waveform.

Regarding the weight update, when the error between the combined signal and the reference signal (multicarrier known signal replica) becomes equal to or less than a predetermined level, it is assumed that the weight has sufficiently converged and the weight update processing is terminated ( S10
8). The multi-carrier signal demodulator 6 demodulates the output of the adaptive array.

In this embodiment, as shown in FIG. 2, the transmission band of the multicarrier known signal is Bm, and the transmission time of the multicarrier known signal is Tm. At this time, the arrival path delay time resolution of the adaptive array is 1
/ Bm [s], and the Doppler frequency resolution is given by 1 / Tm [Hz]. FIG. 5 is a diagram illustrating an example of the beam pattern 21 formed using the adaptive array according to the present embodiment. In the figure, the arrival path 19 is an arrival path having a delay time of 1 / Bm or more with respect to the arrival path 18, and the arrival path 19 is suppressed by the adaptive array. The arrival path 20 is a path having a Doppler frequency difference of 1 / Tm or more with respect to the arrival path 18, and also in this case, the signal is suppressed by the adaptive array.

As described above, according to the adaptive array antenna of the present embodiment, it is possible to combine and separate incoming paths using a known multicarrier signal. Delay time is 1
/ Bm [s] and paths whose Doppler frequency is within 1 / Tm [Hz] are combined, and the other paths are suppressed. Therefore,
It is possible to prevent the characteristics of the received signal from deteriorating due to the influence of the Doppler frequency of the multicarrier signal that varies depending on the path. Further, by setting the transmission bandwidth Bm of the multicarrier known signal, it is possible to set the delay time of the incoming path to be separated, and by setting the transfer time Tm of the multicarrier known signal,
The Doppler frequency difference of the incoming path to be separated can be set. In the above description, the known signal is inserted into all the carriers of the multi-carrier signal and transmitted. However, the present invention is not limited to this, and the known signal is inserted into any of a plurality of carriers. Is also good.

Second Embodiment Next, a second embodiment of the present invention will be described.
The embodiment will be described with reference to FIGS. FIG. 6 is a diagram illustrating a basic configuration of a second embodiment of the signal receiving apparatus of the present invention. In the figure, 1 is an antenna, 2 is A /
D converter, 3 a weight multiplier, 4 an adder, 30 a weight control unit, 31 a multi-carrier signal demodulation unit, 32
35 represent a demodulated signal. FIG. 7 is a diagram illustrating a transmission signal format used in the present embodiment.
42 to 42 are multicarrier signals, 43 is a known signal insertion unit in a frame, and 44 is an information signal insertion unit. FIG. 8 is a flowchart illustrating a procedure of weight control in the adaptive array according to the present embodiment. FIG. 9 is a diagram illustrating an example of a frequency spectrum according to the present embodiment, and 45 indicates a state of fading fluctuation at each frequency.

First, the format of a multicarrier signal transmitted using FIG. 7 will be described. In this embodiment, a known signal is inserted into some carriers instead of inserting a known signal into all carriers as in the first embodiment described above. In FIG. 7, the carrier 36,
Reference numerals 39 and 42 denote carriers into which known signals are inserted.
7, 38, 40 and 41 are carriers into which no known signal is inserted. Here, the known signal is inserted every K carriers, that is, at equal intervals. However, this is not always necessary, and the carrier into which the known signal is inserted can be arbitrarily selected. Note that the known signal is inserted into a plurality of carriers selected in the same time zone.

Hereinafter, the adaptive array according to the present embodiment will be described with reference to FIGS. First, in the signal receiving device, after setting the initial weight in each weight multiplier 3 (S201), the multi-carrier signal is received using the plurality of antennas 1 shown in FIG. 6 (S202).
Next, after each A / D converter 2 converts the received signal from the corresponding antenna 1 into a digital signal, the corresponding weight multiplier 3 uses the previously set initial weight to convert the received signal from each antenna. Are multiplied by weights, and the adder 4 performs signal addition (S203). The added signal (combined signal) is input to the multi-carrier signal demodulation unit 31, and a signal corresponding to each carrier is output (S204).

Next, carrier data for which a known signal is inserted is extracted from the signal of each carrier output from the multicarrier signal demodulation unit 31 (S205), and a multicarrier signal is created again (S206). That is, as shown in FIG. 6, for signals corresponding to carriers (frequency # 1, # K + 1,..., # NK + 1) into which known signals are inserted, carrier waves (f
, F1 + KΔf,..., F1 + NKΔf), and the signals 32, 3
3, 34... 35 are generated and added by an adder to create a multicarrier signal. Here, the created multicarrier signal can be regarded as a multicarrier signal (hereinafter, referred to as a multicarrier known signal) obtained by extracting only the carrier in which the known signal is inserted.

The multicarrier known signal created in this way is input to the weight control unit 30 (S207), and weight calculation is performed according to a predetermined algorithm similar to that described above. After the calculation is performed, the weight control unit 3
At 0, the update weight is output to each weight multiplier 3, and
Weight update is performed (S209). The weight control unit 30 has a signal replica corresponding to the multicarrier known signal in advance, and determines the weight in a direction that minimizes the square error between the multicarrier known signal and the signal replica. Then, the processing of steps S203 to S209 is repeated until the error between the multicarrier known signal and the signal replica becomes equal to or smaller than a predetermined value.

As described above, in the present embodiment, the weight of the adaptive array is determined by using the known signal inserted into some of the multicarrier signals. Whereas in the first embodiment described above, known signals are simultaneously inserted into all carriers, the main reason for inserting known signals into partial carriers in the present embodiment is that In fading in a propagation environment. That is, in a wireless propagation environment, adjacent carriers often follow the same fading fluctuation.
Also, as the carrier spacing widens, it follows different fading variations. Therefore, even if the number of known signals of adjacent carriers having high correlation with fading fluctuation is reduced, the same propagation characteristics are expressed by other carriers, and the influence on weight determination of the adaptive array is small.
Therefore, it is efficient if the known signal is inserted at a frequency interval equal to the fading correlation bandwidth B as shown in FIG. In this case, the fading fluctuation characteristic at each frequency can be efficiently represented using a small number of known signals. As described above, according to the present embodiment, the first
The transmission efficiency of the information signal can be improved as compared with the embodiment.

(Third Embodiment) This embodiment is basically constructed by efficiently combining the first and second embodiments described above. FIG. 10 is a diagram illustrating a basic configuration of the signal receiving device of the present embodiment. In the figure, 1 is an antenna, 2 is an A / D converter, 3 is a weight multiplier, 4 is an adder, 30 is a weight control unit, 31 is a multicarrier signal demodulation unit, and 50 is a known signal multicarrier conversion unit. Note that the known signal multi-carrier unit 50 has the same configuration as the portion surrounded by the broken line in FIG. 6 described above. FIG. 11 is a diagram showing a format of a transmission signal in the present embodiment.
Reference numeral 6 denotes an all carrier known signal insertion unit, and reference numerals 47 to 49 denote partial carrier known signal insertion units. FIG. 12 is a flowchart showing a control procedure according to the present embodiment.

First, the format of a multicarrier signal transmitted in this embodiment will be described with reference to FIG. As shown in the figure, in this embodiment, all known carrier signals and known partial carrier signals are temporally used together. That is, the known signal insertion section 46 inserts a known signal into all carriers, for example, inserts a known signal into all carriers every predetermined number of frames. On the other hand, in other frames,
As shown by the partial carrier known signal insertion units 47 to 49,
A known signal is inserted in some carriers.

Hereinafter, the contents of processing in the signal receiving apparatus of the present embodiment will be described with reference to FIGS. First, the receiving station sets an initial weight in each weight multiplier 3 (S301). When the multicarrier signal is received, first, the above-described all-carrier known signal insertion unit 46 is detected, and the weight control unit 30 uses the synthesized signal output from the adder 4 and the all-carrier known signal replica to perform adaptive processing. The weight of the array is determined (S302). This specific weight determination method follows the method of the above-described first embodiment (FIG. 4). When the weight of the adaptive array antenna is determined in this way, the receiving station can receive a signal using the adaptive array (S303). Then, demodulation of the multicarrier signal is also possible. When the demodulation of the multicarrier signal becomes possible, the weight control unit 30 performs the partial carrier known signals 47 to 49 and the partial carrier known signals from the known signal multicarrier conversion unit 50 in the same manner as in the second embodiment. Weight update processing is performed using the replica (S304). Further, if the next frame has a partial carrier known signal, the process returns to step S
The process is repeated from step 303. If the next frame has all carrier known signals, step S30
The process is repeated from step 2.

As described above, in this embodiment, in the initial acquisition stage, the weight is determined by the known signals of all carriers, and the initial acquisition and multicarrier signal demodulation are established. In the initial acquisition stage, it is necessary to establish symbol timing synchronization and carrier frequency synchronization. Thus, weight determination is performed using known signals of all carriers, and symbol timing synchronization and frequency A method of establishing synchronization is effective. Also,
At the stage where symbol timing synchronization and frequency synchronization become possible and demodulation of a multi-carrier signal becomes possible, weight can be updated using a known partial carrier signal while performing communication. Therefore, by using the partial carrier known signal as in the present embodiment, the insertion area of the known signal can be reduced, and the transmission efficiency can be improved.

In the above description, a known signal is inserted into all carriers by the all-carrier known-signal insertion unit, and a known signal is inserted into some carriers by the partial-carrier known-signal insertion unit. Without inserting a known signal into a first predetermined number of carriers every predetermined frame,
In other frames, the known signal may be inserted into a second predetermined number of carriers smaller than the first predetermined number. Further, in the above, the all-carrier known signal insertion unit is arranged for each predetermined frame, but the frame position where the known signal is arranged on all carriers or the first predetermined number of carriers does not need to have a fixed period. , Can be set at any timing.

(Fourth Embodiment) In the present embodiment, a signal transmission format different from that of the third embodiment is used. FIG. 13 is a diagram showing a transmission signal format according to the present embodiment.
Represents an all-carrier known signal insertion unit, and 47 to 49 represent partial carrier known signal insertion units.

The format of a multicarrier signal transmitted in the present embodiment will be described with reference to FIG. In the present embodiment, as in the third embodiment, the known two-carrier signal and the known partial carrier signal are temporally used together. That is, the known signal insertion section 46 inserts a known signal into all carriers. On the other hand, the partial carrier known signal insertion units 47 to
In 49, a known signal is inserted into some carriers. At this time, the partial carrier known signal insertion section changes the carrier into which the known signal is inserted every time. By changing the carrier into which the known signal is inserted, the known signal can be arranged uniformly in the time-frequency domain. In the present embodiment, processing can be performed according to the configuration shown in FIG. 10, and the known signal multicarrier generation section 50 extracts only the known signal section and converts it to multicarrier. The processing procedure in the present embodiment is the same as the procedure in the third embodiment shown in FIG.

(Fifth Embodiment) This embodiment is configured using a signal transmission format different from those of the third and fourth embodiments. However, the basic configuration of this embodiment is the same as that of the fourth embodiment, as shown in FIG.
It is represented by 0. FIG. 14 is a diagram illustrating a transmission signal format according to the present embodiment. In the present embodiment, known signals are always inserted into specific carriers 51, 54, and 57 at timings other than the all-carrier known signal insertion unit. Like that. The processing procedure of this embodiment is the same as that of the third embodiment shown in FIG. 12, but in this embodiment, the known signal always inserted into specific carriers 51, 54, 57 , The weight control process is performed with temporal continuity. According to this embodiment, since the known signal is data for a long time, the resolution with respect to the Doppler frequency can be improved.

[0035]

As described above, according to the radio receiving apparatus of the present invention, a wideband multicarrier signal can be used.
The adaptive array technology can be applied.
In particular, it becomes possible to separate an incoming path for each Doppler frequency with respect to a wideband multicarrier signal having a weak point that the reception characteristic is greatly deteriorated with respect to the Doppler frequency, and it is possible to greatly improve the reception characteristic. Further, the present invention can be applied to a multicarrier signal having an arbitrary transmission bandwidth. Further, the Doppler frequency required for receiving the information signal,
It is possible to select and receive a condition of a reception arriving path concerning a delay time or the like using a known signal and receive the signal. Furthermore, it is possible to suppress the component of the interference signal in the combined signal, and it is possible to receive a high-quality signal.

Further, according to the present invention, in which the known signal is arranged on a carrier having a predetermined frequency interval, the transmission efficiency can be improved. Further, according to the present invention in which the known signal is always arranged on a specific carrier, it is possible to improve the transmission efficiency and further improve the resolution with respect to the Doppler frequency. Furthermore, according to the present invention, in the initial stage of communication, weight control is performed using the output from the combining unit, and in the subsequent stage, weight control is performed using the demodulated signal from the multicarrier demodulation unit. For example, in the initial acquisition stage, various synchronizations can be established under better reception characteristics, and after the acquisition is completed, the insertion area of the known signal can be reduced, thereby improving the transmission efficiency. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a most basic configuration of a first embodiment of a wireless reception device according to the present invention.

FIG. 2 is a diagram showing a signal transmission format used in the first embodiment according to the present invention.

FIG. 3 is a diagram illustrating an example of a signal waveform of a known signal used in the first embodiment according to the present invention.

FIG. 4 is a flowchart illustrating a control procedure according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of a beam pattern of an adaptive array according to the first embodiment of the present invention.

FIG. 6 is a diagram illustrating a most basic configuration of a second embodiment of the wireless reception device according to the present invention.

FIG. 7 is a diagram illustrating a signal transmission format used in a second embodiment according to the present invention.

FIG. 8 is a flowchart illustrating a control procedure according to a second embodiment of the present invention.

FIG. 9 is a spectrum diagram illustrating a channel environment according to a second embodiment of the present invention.

FIG. 10 is a diagram illustrating a most basic configuration of a third embodiment of the wireless reception device according to the present invention.

FIG. 11 is a diagram illustrating a signal transmission format used in a third embodiment according to the present invention.

FIG. 12 is a flowchart illustrating a control procedure according to a third embodiment of the present invention.

FIG. 13 is a diagram illustrating a signal transmission format used in a fourth embodiment of the wireless reception device according to the present invention.

FIG. 14 is a diagram illustrating a signal transmission format used in a fifth embodiment of the wireless reception device according to the present invention.

FIG. 15 is a diagram illustrating a basic configuration of a conventional wireless receiving apparatus.

FIG. 16 is a diagram illustrating a signal transmission format used in a conventional wireless receiving device.

FIG. 17 is a flowchart illustrating a control procedure in a conventional wireless receiving device.

FIG. 18 is a diagram illustrating an example of an adaptive array beam pattern in a conventional wireless receiving device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Antenna 2 A / D converter 3 Weight multiplier 4 Adder 5, 30 Weight control part corresponding to multicarrier signal 6, 31 Multicarrier signal demodulation part 7-9 Multicarrier signal 11 Known signal 12 Information signal 46 All carrier known signal 47-49 Partial carrier known signal 50 Known signal multi-carrier unit

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Akinori Taira 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation F-term (reference) 5J021 AA05 AA06 CA06 DB03 EA04 FA14 FA20 FA26 FA29 FA32 GA02 HA05 HA10 JA02 5K059 CC03 CC04 DD33 DD37 EE02

Claims (8)

[Claims] A plurality of antennas; a plurality of weight multipliers for multiplying a reception signal from each corresponding antenna by a predetermined weight; a combining unit for combining outputs of the weight multipliers; A weight control unit that determines the weight by using a reception signal corresponding to a known signal transmitted to a plurality of output carriers. 2. The radio receiving apparatus according to claim 1, wherein the known signal has the same frequency band as an information signal. 3. The weight control unit minimizes a square error between a received signal corresponding to a known signal arranged and transmitted on the plurality of carriers and a replica of the known signal arranged on the plurality of carriers. 2. The radio receiving apparatus according to claim 1, wherein a weight determining algorithm is used. 4. A plurality of antennas, a plurality of weight multipliers for multiplying a reception signal from each corresponding antenna by a predetermined weight, a combining unit for combining outputs of the weight multipliers, 1. A radio receiving apparatus comprising: a multicarrier demodulation unit that performs multicarrier demodulation on a combined signal of the above; and a weight control unit that determines the weight using a demodulated signal from the multicarrier demodulation unit. 5. The wireless reception according to claim 4, wherein the weight control unit determines the weight using a demodulated signal corresponding to a known signal transmitted by being allocated to a plurality of carriers. apparatus. 6. The radio receiving apparatus according to claim 5, wherein the known signal is arranged on a carrier having a predetermined frequency interval. 7. The radio receiving apparatus according to claim 5, wherein the known signal is always arranged on a specific carrier. 8. A plurality of antennas, a plurality of weight multipliers for multiplying a received signal from each of the corresponding antennas by a predetermined weight, a combining unit for combining outputs from the respective weight multipliers, and the combining unit A multi-carrier demodulation unit that performs multi-carrier demodulation on a combined signal from the, and a wireless receiving device having a weight control unit that determines the weight, wherein the weight control unit, in the initial stage of communication, The weight is determined using a received signal corresponding to a known signal transmitted by being arranged on a first predetermined number of carriers output from the combining unit, and in a subsequent communication step,
The weight is determined by using a demodulated signal of the multi-carrier demodulation unit corresponding to a known signal arranged on a second predetermined number of carriers smaller than the first predetermined number. Wireless receiver.