JPH09246843A - Adaptive array reception system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the adaptive array reception system to set a weight at a high speed in a direction in which the S/N is maximized by providing plural branches, a demodulation means, a synthesis processing means and a weight calculation means. SOLUTION: Demodulation means 121 -12N demodulate reception waves caught by branches 111 -11N in parallel in the order of time series, separate a field including a known symbol or transmission information in the unit of frames and obtain a vector Rkn (1<=k<=N) corresponding to a symbol included in the field in a signal space. A weight calculation means 14 obtains a difference δkn between a reference vector dn denoting a known symbol and a weighted sum ΣWkn .Rkn of vectors Rkn and then obtains weights Wk(n+1) sequentially expressed in a recurrence formula Wk(n+1) =Wkn +μR*δkn +υ(dn /NRkn -Wkn ), where R*kn is a conjugate vector of the vector Rkn and μ, ν are coefficients representing the convergence form. Then a vector sum denoting excellent transmission information or the known symbol is obtained by a synthesis processing means 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention combines received waves arriving in parallel to a plurality of antennas under weighting based on an adaptive algorithm, and dynamically sets a main lobe in the direction of arrival to perform reception processing. The present invention relates to an adaptive array reception method for performing.

[0002]

2. Description of the Related Art In a mobile station of a mobile communication system, the direction of arrival of a received wave to be received constantly fluctuates in accordance with the movement of the mobile station or the switching of a channel during a call, and it is formed with a radio base station. Along with such movement, the transmission characteristics of the wireless transmission line significantly change according to changes in topography, features, and the like. Therefore, in the current digital mobile communication system, in order to form a wireless transmission path with good transmission quality under such transmission characteristics, it is possible to reduce the wireless zone into small zones and reuse the radio frequency. In addition, mobile stations often employ antenna systems that perform antenna switching diversity on a frame-by-frame basis.

Further, in recent years, the number of subscribers has increased due to the liberalization of the market and the competition by a plurality of communication businesses, and the information amount of transmission information has also increased in accordance with the diversification of required service forms. Since the tendency is remarkable, it is a technical subject to secure good transmission quality at low cost while maximally utilizing the limited radio frequency. The adaptive array reception system is being studied for application in order to be compatible with many technologies being researched and developed under such circumstances and to have interference resistance against multipath and the like.

FIG. 6 is a diagram showing a configuration example of a conventional adaptive array reception system. In the figure, the feeding ends of the plurality of antennas 31 _{1 to} 31 _N are respectively the receiving units 32 ₁
.About.32 _N to the bus 33, which is connected to a digital signal processor ((DSP) or below, simply "D
"SP". ) 34 bus terminals are connected. Also,
The reception unit 32 ₁ includes a cascaded low noise amplifier (LNA) 35 ₁ , a mixer (MIX) 36 ₁ , an AGC amplifier (AGC) 37 ₁ , a demodulator (DET) 38 ₁ and an AD converter (A / D). ) 39 ₁ . Note that the receiving units 32 _{2 to} 32 _{N have} the same configuration as the receiving unit 32 ₁ , so that the same reference numerals with subscripts “2” to “N” are given to corresponding components below. The description is omitted here.

In the adaptive array receiving system having such a configuration, as shown in FIG. 6, the antennas 31 _{1 to} 31 _N receive waves digitally modulated in units of frames including a reference signal composed of a known bit string. Is coming. In the receiving unit 32 ₁ , the mixer 36 ₁ thus frequency-converts the received wave that arrives at the antenna 31 ₁ and is amplified by the low noise amplifier 35 ₁ to generate an intermediate frequency signal. The intermediate frequency signal is the AGC amplifier 3
7 ₁ As variation in the level is orthogonally demodulated by a demodulator 38 ₁ after it has been smoothed by, AD converter 39 ₁ of the quadrature demodulation signal obtained as a result of the quadrature demodulation A / D
A digital signal is generated by the conversion.

Since the operation of the receiving units 32 _{2 to} 32 _N is the same as the operation of the receiving unit 32 ₁ described above, the description thereof is omitted here. The digital signals individually generated by the receiving units 32 _{1 to} 32 _{N in} this manner are fetched by the DSP 34 via the bus 33 and are subjected to the processing described later, which is performed in the digital domain. Since the vector in the signal space of the quadrature demodulated signal represented by these digital signals is the operation target, in the following, for simplification, it will be described as an analog domain process that faithfully represents the physical meaning of the process target and procedure. .

The DSP 34 includes a receiving unit 32.₁~ 32_N
From the quadrature demodulated signal obtained by
Common frame (received in the order of time series n
Individual reference signal component (hereinafter,
It is called a "received reference signal". ) R _1n~ R_NnTo extract (Figure
7 (1)). Further, the DSP 34 has the antenna 31.₁~ 31_N
Identification number i, which corresponds to
The initial value is set according to the algorithm described later.
Weight W updated in the order of time series n_inAgainst

[Equation 1] The received signal x _n corresponding to the vector sum of the components of the received reference signal in the received waves arriving at each antenna is calculated by performing the arithmetic operation represented by the formula (2) in FIG.

Further, the DSP 34 calculates an error amount δ _n of the received signal by calculating the distance in the signal space between the received signal x _n thus calculated and the known transmission reference signal S _n (see FIG. 7 (3)), and the identification number k individually corresponding to the antennas 31 _{1 to} 31 _N , like the identification number i,
A conjugate complex number r ^* _kn of a complex number indicating the received reference signal _rkn corresponding to the identification number, and a coefficient μ (<
2 / λ _max ) and by applying the LMS (Least Mean Square Error) method represented by the formula of W _{k (n + 1)} = W _kn + μr ^* _kn δ _n (2), The weight W _{k (n + 1)} is sequentially obtained (FIG. 7 ₎ .
(Four)). Note that λ _max is the correlation sequence E of the received reference signal.
It is the maximum value of the eigenvalues of [(r _k1 , ..., R _kN ) ^H (r _k1 , ..., R _kN )].

By the way, regarding the received reference signal r _in ,
When the propagation losses of the wireless transmission lines individually formed between the antennas 31 _{1 to} 31 _N and the transmission end (not shown) are the same, the known transmission reference signal S _n and the respective antennas arrive individually. It is expressed by the equation of r _in = S _n e ^j θ ⁿ with respect to the phase θ _in of the received wave. When the LMS method converges, the received signal x _n becomes equal to the transmitted reference signal S _n , and the equation of x _n / S _n = ΣW _in · e ^j θ ⁿ = (1 + 0 · j) holds and the received wave arrives. The main lobe is formed in the direction of

Therefore, in a mobile station of a mobile communication system to which such an adaptive array reception system is applied, a radio transmission path is constantly formed between an opposing radio base station and an antenna system having a high gain, and Unnecessary received waves arriving due to multipath and the like are efficiently suppressed. Note that as a document describing such a conventional adaptive array reception system, for example, Hayki
n, "Adaptive Filter Theory" Prentice-Hall.

[0011]

By the way, in such a conventional example, for the sake of simplicity, for example, the antennas 31 _{1 to} 3 are used.
1 when the number N of the _N is ^{_{"2", W 1n · e + j θ}} 1n + W 2n · e + j θ 2n = 1 + 0 · j ··· (3) the weight W _1n the expression is satisfied, the As shown in FIG. 8 (a), W _2n is located on the straight line represented by the formula of W _1n + W _2n = 1 in three orthogonal coordinate systems that individually show these weights and errors δ _n. . In addition, in FIG.
For simplicity, W _1n and W _2n , which are originally complex numbers, are illustrated as real numbers when the respective equations of e ^j θ ¹ⁿ = 1 e ^j θ ²ⁿ = 1 are satisfied.

However, the combination of the weights W _1n and W _2n given by such a straight line is not specified under the above-mentioned LMS method, and these weights have a high distance at a high speed with respect to the origin of the Cartesian coordinate system. Since it does not converge to the shortest value, there is a high possibility that a noise component proportional to Σ | W _in | ² will be superimposed, as shown in FIG. 8 (b). That is, in the conventional example, even if a tentative convergence condition is satisfied under adaptive control of weights, the SN ratio does not necessarily become the maximum, and the direction of the main lobe is accurately oriented toward the opposite radio station. Didn't.

Further, in the conventional example, adaptive control for updating the weight W _in is performed _{in a} direction in which the above-mentioned noise component becomes smaller on average, but since the direction of the adaptive control is not fixed, it is practically used. No high responsiveness was obtained. When the direction in which the received wave arrives is known, the DCMP adaptive array method (the Institute of Electronics, Information and Communication Engineers, B- II, (1992-11) "Progress of adaptive antenna theory and future prospects", Yasutaka Ogawa,
Nobuyoshi Kikuma p.721) is applicable.

However, it has not been practically applicable to a radio transmission system such as a mobile communication system in which such directions are not constant and remarkable multipath occurs. It is an object of the present invention to provide an adaptive array receiving system that sets weights at high speed in the direction of maximum SN ratio.

[0015]

FIG. 1 is a block diagram showing the principle of the first and second aspects of the present invention.

The invention according to claim 1 is phase-modulated or amplitude-phase-modulated by a frame including a field in which known symbols or transmission information are arranged, and a plurality of N received waves which catch in parallel are received. Branch 11 ₁
~ 11 _N and the received waves captured by the plurality of branches 11 _{1 to} 11 _N are demodulated in parallel in the order of time series n, and the fields are separated into frame units and included in the fields on the signal space. N demodulating means 12 ₁ for obtaining a vector R _kn (1 ≦ k ≦ N) corresponding to the symbol
˜12 _N and weights W given as initial values or obtained in advance for all values of k (1 ≦ k ≦ N)
_kn and a combination processing means 13 for obtaining a weighted sum by taking the sum of the products of the vectors R _kn obtained by the plurality of demodulation means 12 _{1 to} 12 _N , and a reference vector indicating transmission information or a known symbol in the signal space. calculates a difference [delta] _n of the weighted sum obtained by d _n and synthesis processing unit 13, the difference,
Coefficient indicating the conjugate vector R ^* _kn and converging in the form of a vector R _kn mu, with respect to _{ν, W k (n + 1} ) = W kn + μR * kn δ n
+ [Nu weights W _k represented by recurrence formula _{(d n / NR kn -W kn} ) (n
₊₁₎ to obtain the weight W _kn and update the weight W _kn ;
It is characterized by having.

According to the invention described in claim 2, in the adaptive array receiving system according to claim 1, known symbols and transmission information are arranged in different fields, and a plurality of demodulating means 12 _{1 to} 12 _N are A field in which known symbols and transmission information are arranged is separated, and a vector R _kn corresponding to symbols individually included in these fields,
A means for obtaining R _kn ′ (1 ≦ k ≦ N) is included, and the weight calculation means 14 corresponds to a field in which a known symbol is arranged among the fields separated by the plurality of demodulation means 12 _{1 to} 12 _N. By applying the coefficients μ, ν and the coefficients μ ′ (<μ), ν ′ (<ν) corresponding to the fields in which the transmission information is arranged to the recurrence equation individually, The synthesis processing means 13 includes means for obtaining corresponding weights W _{k (n + 1)} and W _{k (n + 1)} ′, and the synthesis processing means 13 has weights W _{k (n + 1)} and W _{k (n + 1)} .
It is characterized by including means for obtaining a weighted sum individually corresponding to _{k (n + 1)} '.

In the adaptive array receiving system according to the invention described in claim 1, the demodulating means 12 _{1 to} 12 _N demodulate the received waves captured by the branches 11 _{1 to} 11 _N in parallel in the order of time series n. , And a field containing a known symbol or transmission information is separated for each frame unit, and a vector R _kn (1 ≦ k ≦ N) corresponding to the symbol included in the field is obtained on the signal space. The weight calculating means 14 obtains a difference δ _n between the weighted sum ΣW _kn · R _kn of the reference vector d _n and the vector R _kn indicating the transmission information or the known symbol described above in the signal space, and together with the difference, coefficient indicating the conjugate vector R ^* _kn and converging in the form of a vector R _kn mu, with respect to _{ν, W k (n + 1} ) =
^{_{W kn + μR * kn δ n}} + ν sequentially obtains the weight W _k represented by recurrence formula _{(d n / NR kn -W kn} ) (n + 1).

In such recurrence formula, the term (d _n / NR
_kn ) is a small value obtained by dividing the above-mentioned reference vector d _n into N equal parts when all of the integers i (1 ≦ i ≦ N) in the time series n are considered to have the same vector R _in. It shows the ratio of the vector (= d _n / N) and the vector R _kn, and generally corresponds to the optimum weight that minimizes the value of Σ | W _in | ² .

[0020] That is, since the term _{(d n / NR kn -W kn} ) is the weight W _kn obtained prior corresponds to the error with respect to its optimal weight, corresponding to this and the weight W _kn The error that the vector represented by the product of the received vector R _kn has with respect to the small vector is surely compressed, and the main lobe is dynamically and efficiently set in the direction in which the received wave arrives, and the SN ratio is increased. Maintained high.

Therefore, as long as it is considered that the transmission characteristics of the wireless transmission path are the same during the period in which the reference field and the information field included in the received wave are transmitted, the synthesizing means 13 has k (1≤ The weight W _{k (n + 1)} thus obtained for all values of k ≦ N ₎
By obtaining the sum of the products of the following vector R _{k (n + 1)} obtained by the demodulation means 12 _{1 to} 12 _N , the vector sum indicating the transmission information or the known symbol can be obtained with good transmission quality. You can

In the adaptive array receiving system according to the second aspect, in the adaptive array receiving system according to the first aspect, the known symbols and the transmission information are arranged in different fields, and the demodulating means 12 _{1 to} 12 _N are The fields in which the known symbols and the transmission information are arranged are separated, and the vectors R _kn and R _kn ′ (1 ≦ k ≦ N) corresponding to the symbols individually included in these fields are obtained. The weight calculating means 14 has coefficients μ and ν corresponding to fields in which known symbols are arranged among the fields separated in this way, and coefficients μ ′ and ν ′ corresponding to fields in which transmission information is arranged. By individually applying and to the recurrence formula, the weights W _{k (n + 1)} and W _{k (n + 1)} ′ corresponding to the individual fields are _obtained . Further, the synthesis processing means 13 obtains the weighted sum individually corresponding to these weights _{Wk (n + 1)} and _{Wk (n + 1)} '.

That is, the direction of the main lobe is updated even during the reception of the field in which the transmission information is arranged along with the known symbol, but the direction is regressed as described above. The coefficient applied to the equation is μ ′
Since the inequalities of <μ and ν ′ <ν are set to the values that hold, even if prediction or predictive decoding can be performed at the receiving end,
Since the accuracy of the result is low in accordance with the superposition of noise on the transmission path, the possibility of abrupt update in an abnormal direction can be suppressed.

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 2 is a diagram showing an embodiment corresponding to the invention described in claims 1 and 2. In the drawing, components having the same functions and configurations as those shown in FIG. 6 are denoted by the same reference numerals, and description thereof is omitted here.

The difference between the present embodiment and the conventional example shown in FIG. 6 is that a digital signal processor (DSP (hereinafter simply referred to as "DSP")) 21 is used instead of the DSP 34.
Is provided. As to the correspondence relationship between the block diagram shown in this embodiment and FIG. 1, the antenna 31 ₁ -
31 _N corresponds to the branches 11 _{1 to} 11 _N , the receiving units 32 _{1 to} 32 _N correspond to the demodulation means 12 _{1 to} 12 _N , and the DSP
Reference numeral 21 corresponds to the weight calculation means 13 and the combination processing means 14.

FIG. 3 is a diagram for explaining the operation of this embodiment corresponding to the invention described in claim 1. Hereinafter, the operation of the present embodiment will be described with reference to FIGS. In addition,
In this embodiment, the operation of each unit of the receiving units 32 _{1 to} 32 _N is the same as that of the conventional example, and therefore the description thereof is omitted here.

In the conventional example, Σ | W_in|^Two The value of
It did not converge to the minimum value, but that value was
Is the minimum weight (hereinafter referred to as the "optimal weight").
U. ) W _inIs generally a reference signal known in the signal space.
Vector d indicating signal point_n In contrast, as shown in Fig. 3 (a)
A small vector obtained by dividing the vector into N equal parts
Le (= d_n/ N) and the antenna 31₁~ 31_NAs one end
In parallel, a wireless transmission line formed separately between the transmitter and
Received reference signal obtained under the same propagation loss
r_inRatio with (= d_n/ Nr_in).

On the other hand, the DSP 21 has the above-mentioned vector d.
coefficient determining the _n, the speed of convergence ν (<1) is given to the _{W k (n + 1) =} W kn + μr * kn δ n + ν (d n / Nr kn -W kn) ·· The weight W _{k (n + 1)} is _obtained by applying the equation (4) instead of the equation (2) to perform adaptive control.

In the process of such adaptive control, the above equation (4)
The term (d _n / Nr _kn ) included in the above corresponds to the optimum weight described above, and the term (d _n / Nr _kn −W _kn ) has the weight W _kn obtained in advance with respect to the optimum weight. Since it indicates an error, for example, when the vector represented by the product of the weight W _kn and the reception reference signal r _kn received corresponding thereto is not equal to the small vector described above, FIG. The error indicated by the dotted line in Fig. 6 is reliably and promptly compressed as shown by the dotted line in Fig. 6 (c).

That is, according to this embodiment, Σ | W _in |
^{Since the} condition that the value of ² is the minimum (the weights W _in are all equal _in size for each time series n) is surely set as the convergence condition of the adaptive control, the SN is faster than the conventional example. The ratio is maximized, and the main lobe is accurately formed in the direction in which the received wave arrives. Therefore, in the wireless station to which the present invention is applied, the transmission quality is improved as compared with the conventional example, and interference such as multipath is efficiently suppressed, as compared with FIGS. 4 (a) and 4 (b). To be done. In addition, the transmission wave is efficiently radiated toward the opposite radio station via the radio transmission path to save power consumption and the interference of the transmission wave radiated from the own station on other stations is suppressed. In addition, a wireless transmission path with stable transmission quality is formed while dynamically following changes in the relative directions of opposing wireless stations.

Although the number of symbols included in the reference signal is not shown in the above embodiment, the present invention
The number of symbols may be either singular or plural as long as the weight is surely updated at a speed that can follow the fluctuation of the transmission characteristic of the wireless transmission path and the change of the direction in which the received wave arrives. Further, when the number of such symbols is plural, as long as the weight is surely updated with desired accuracy and speed,
The update may be based on some of these symbols.

Further, although the length of the information frame is not shown at all in the above-mentioned embodiment, the transmission characteristic of the wireless transmission line and the received wave are so large that the weight obtained based on the above-mentioned algorithm is regarded as effective. The length can be any value as long as the change in the direction of arrival is small.
Hereinafter, the operation of this embodiment corresponding to the invention described in claim 2 will be described with reference to FIGS. 2 and 3. The feature of the present embodiment lies in the calculation performed by the DSP 21, and the operation of each of the other parts is the same as that of the embodiment corresponding to the invention described in claim 1, and therefore the description thereof is omitted here.

In addition to the above-described vector d _n , the DSP 21 sequentially determines the result as a vector d _n ′ by performing signal determination for the frame in which the transmission information is arranged under the applied frame structure. Also, DS
P21 is the same as in the embodiment corresponding to the invention according to claim 1 during the period when the reference signal is received.
The weight W _{k (n + 1)} is _obtained by performing the adaptive control based on (4).

Further, the DSP 21 makes the coefficients μ ′ and ν ′ that satisfy the inequality of the above vector d _n ′ and μ ′ <μ ν ′ <ν while the above-mentioned field of the transmission information is being received. Weights _{Wk (n + 1)} 'are obtained by applying a recurrence formula obtained by applying the above formula (4) in place of μ and ν to perform adaptive control.

That is, the fact that the accuracy of the vector d _n ′ may be reduced due to noise or the like superimposed on the transmission line is compensated by setting the coefficients μ ′ and ν ′ under the condition that the above inequality holds. In addition, the direction of the main lobe is updated even while the field in which the transmission information is arranged is being received. Therefore, the possibility that the main lobe is rapidly updated in an abnormal direction in response to such noise and the like is suppressed to a low level, and the time rate of the period during which adaptive control is performed is increased. The stability of the adaptive control and the responsiveness to the change in the relative direction with the opposing wireless station are improved as compared with the embodiment corresponding to the invention.

In this embodiment, the adaptive control is performed during the period when the reference signal is received, but the present invention is not limited to such a configuration, and the field in which the transmission information is arranged is received. If sufficient accuracy and responsiveness are ensured under adaptive control only during the period, adaptive control during the period during which the reference signal is received is omitted, or a frame structure that does not include such a reference signal is applied. May be done.

Further, in the present embodiment, the description of the specific calculation and processing for obtaining the vector d _n ′ is omitted, but such calculation and processing are performed by, for example, decision feedback and maximum likelihood sequence estimation. Or when the transmission information is coded under the channel coding method, the predictive coding process may be performed based on the bit (symbol) sequence obtained as a code sequence. Many known techniques are applicable.

[0038]

As described above, according to the first aspect of the invention, it is considered that the transmission characteristics of the wireless transmission line are the same during the period in which the reference field and the information field included in the received wave for each frame are transmitted. As long as the main lobe is dynamically and efficiently formed in the direction in which the received wave arrives while ensuring a high SN ratio, interference such as multipath is significantly and surely suppressed and the transmission quality is improved. In addition, it becomes possible to set the power of the transmission wave to be transmitted to the opposing wireless station via the wireless transmission path to the minimum required value.

Further, in the invention described in claim 2, the direction of the main lobe is updated even during the reception of the field in which the transmission information is arranged, and such a direction is used as the transmission path in the transmission information. It is possible to suppress the possibility of abrupt updating in an abnormal direction due to noise or the like that is superposed on. Therefore, in the wireless transmission system to which the present invention is applied, a good wireless transmission path can be stably secured while flexibly following the changes in the relative directions of the opposing wireless stations, and the running cost can be reduced and efficient wireless transmission can be achieved. The frequency can be used.

[Brief description of drawings]

FIG. 1 is a block diagram showing the principle of the present invention.

FIG. 2 is a diagram showing an embodiment corresponding to the first and second aspects of the present invention.

FIG. 3 is a diagram for explaining the operation of this embodiment.

FIG. 4 is a diagram showing an example of an improvement effect obtained by the present embodiment.

FIG. 5 is a diagram showing a change in bit error rate with respect to a coefficient μ.

FIG. 6 is a diagram showing a configuration example of a conventional adaptive array reception system.

FIG. 7 is an operation flowchart of a conventional example.

FIG. 8 is a diagram illustrating a problem of a conventional example.

[Explanation of symbols]

 11 branches 12 demodulation means 13 synthesis processing means 14 weight calculation means 21, 34 digital signal processor (DSP) 31 antenna 32 receiving unit 33 bus 35 low noise amplifier (LNA) 36 mixer (MIX) 37 AGC amplifier (AGC) 38 demodulator (DET) 39 A / D converter (A / D)

Claims (2)

[Claims] 1. A plurality of N branches 11 _{1 to} 11 _N , which are phase-modulated or amplitude-phase-modulated in a frame including a field in which known symbols or transmission information are arranged, and which receive incoming waves which arrive in parallel. , The received waves captured by the plurality of branches 11 _{1 to} 11 _N are demodulated in parallel in the order of time series n to separate the field into units of the frame and are included in the field on the signal space. A plurality of N demodulating means 12 ₁ for obtaining a vector R _kn (1 ≦ k ≦ N) corresponding to a symbol
˜12 _N, and for all values of k (1 ≦ k ≦ N), weights W _kn given as an initial value or obtained in advance and obtained by the plurality of demodulation means 12 _{1 to} 12 _N Vector R
Synthesis processing means 1 for obtaining the weighted sum by taking the sum of products with _kn
3 and the difference δ _n between the reference vector d _n indicating the transmission information or the known symbol in the signal space and the weighted sum obtained by the combining processing means 13, and the difference, the conjugate vector of the vector R _kn For R ^* _kn and the coefficients μ and ν indicating the form of convergence, W _{k (n + 1)} = W _kn + μR ^*
_kn δ _n + ν (d _n / NR _kn −W _kn ) and a weight calculating means 14 for calculating the weight W _{k (n + 1) represented} by the recurrence formula and updating the weight W _kn. Adaptive array reception method. 2. The adaptive array receiver according to claim 1.
In the communication system, known symbols and transmission information are placed in different fields
A plurality of demodulation means 12₁~ 12_NIs a file in which the known symbol and the transmission information are arranged.
Separate fields and are included individually in these fields
Vector R corresponding to the symbol_kn, R_kn′ (1 ≦ k ≦
N), and the weight calculation means 14 includes the plurality of demodulation means 12₁~ 12_NIsolated by
The field in which the known symbol is placed
The coefficients μ and ν corresponding to the
The coefficients μ ′ (<μ) and ν ′ (<ν) corresponding to the
By applying each to the recurrence equation separately.
Weight W corresponding to each individual_{k (n + 1)}, W _{k (n + 1)}′
The weighting W is included in the combining processing unit 13._{k (n + 1)}, W_{k (n + 1)}Weighting corresponding to each '
Adaptive store characterized by including means for obtaining
Ray reception system.