JP2005150821A - Signal receiving method and signal receiving apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a signal receiving method or the like in wireless communication with a simple configuration wherein the effects of noise and multipath are eliminated. <P>SOLUTION: The signal receiving method for receiving a pilot signal and a data signal for measuring the multi-path characteristic via a transmission path, includes: steps S10 to S13 of estimating the multipath characteristic and noise of the transmission path from the received pilot and data signals for measuring the multipath characteristic; and steps S14 to S17 of estimating a transmitted data signal on the basis of the received data signal in which the effect of the multipath characteristic of the transmission path is excluded and the estimated noise is eliminated. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a signal receiving method and a signal receiving apparatus, and more particularly to a signal receiving method and a signal receiving apparatus in wireless communication with a simple configuration and eliminating the influence of noise and multipath.

In wireless communication, external noise, self-multipath interference, and inter-channel interference greatly affect communication quality. In particular, in mobile communication, since it moves in an urban area or the like, it is greatly affected by general external noise and self-multipath interference. In addition, with the spread of mobile communication, communication between a base station and many mobile stations shares the same band, and interference due to interchannel interference is increasing in addition to external noise and self-multipath interference.
As a conventional technique, when a spread spectrum code and various types of noise are mixed, the receiver system separates them and discriminates and detects noise frequency components, thereby improving the reception demodulation S / N ratio and improving the SS system. There is known a technique for improving the frequency band use efficiency (see Patent Document 1).
JP-A-9-116461

  However, in the invention described in Patent Document 1, there is a problem that it is necessary to identify and detect the frequency component of noise, and it cannot be applied to all wireless communication systems.

  The present invention has been made in view of the above problems, and provides a signal receiving method and a signal receiving apparatus in wireless communication that have a simple configuration and eliminate the effects of external noise, self-multipath interference, and inter-channel interference. It is the purpose.

  In order to solve the above problems, the present invention employs means for solving the problems having the following characteristics.

  According to a first aspect of the present invention, in a signal receiving method for receiving a multipath characteristic measurement pilot signal and a transmission data signal via a transmission line, the multipath characteristic measurement pilot signal is estimated based on the multipath characteristic measurement pilot signal. The multipath characteristic of the transmission path is corrected using a transmission data estimation result estimated using the estimated multipath characteristic of the transmission path.

  According to a second aspect of the present invention, there is provided a signal reception method for receiving a pilot signal for measuring a multipath characteristic and a transmission data signal via a transmission line, and the received pilot signal and transmission data for measuring the multipath characteristic. Based on the received transmission data signal from which the influence of the multipath characteristic of the transmission path is eliminated and the estimated noise is removed. The transmission data signal is estimated.

  According to a third aspect of the present invention, a multipath characteristic measurement pilot signal and a transmission data signal are received via a transmission line, and the multipath characteristic and the transmission data signal of the transmission line are estimated. Using the estimated multi-path characteristics and transmission data signal estimation step, and the estimated transmission data signal and the estimated multi-path characteristics of the transmission path, a noise-free received pilot signal and noise-free received data that are received signals without noise A first noiseless received signal estimating step for estimating a signal, and a multipath characteristic and transmission of the transmission path from the noiseless received pilot signal and the noiseless received data signal estimated by the first noiseless received signal estimating step. A second multipath characteristic for estimating a data signal and a transmission data signal estimation step, the first noiseless received signal estimation step, and 2 multipath characteristic and the transmission data signal estimation step and the N (N is a natural number of 1 or more) after repeated times, and estimates a transmission data signal from the noise-free received data signals estimated.

  According to a fourth aspect of the present invention, in the signal receiving method according to any one of the first to third aspects, the transmission data signal is a signal having an error correction bit.

  According to a fifth aspect of the present invention, in the signal receiving method according to any one of the first to fourth aspects, the multipath characteristic measurement pilot signal and the transmission data have autocorrelation in a predetermined time range. In addition, there is no cross-correlation within a predetermined time range.

  According to a sixth aspect of the present invention, in the signal receiving method according to any one of the first to fifth aspects, the multipath characteristic measurement pilot signal is transmitted in parallel with the transmission data signal. And

  According to a seventh aspect of the present invention, in a signal receiving apparatus that receives a pilot signal for measuring a multipath characteristic and a transmission data signal via a transmission line, the transmission is performed based on the pilot signal for measuring the multipath characteristic. Multipath characteristic measuring means for estimating the multipath characteristic of the road, transmission data estimating means for estimating transmission data using the multipath characteristic estimated by the multipath characteristic measuring means, and transmission data estimating means The multipath characteristic is corrected using the transmitted data.

  According to an eighth aspect of the present invention, in a signal receiving apparatus that receives a pilot signal for measuring a multipath characteristic and a transmission data signal via a transmission line, the received pilot signal and transmission data for measuring the multipath characteristic are received. Based on the received data signal from the signal, the means for estimating the multipath characteristics and noise of the transmission path, the influence of the multipath characteristics of the transmission path is eliminated, and the estimated noise is removed, And means for estimating the transmission data signal.

  According to a ninth aspect of the present invention, a multipath characteristic measurement pilot signal and a transmission data signal are received via a transmission line, and the multipath characteristic and the transmission data signal of the transmission line are estimated. Using the estimated multipath characteristics and transmission data signal estimation means, and the estimated transmission data signal and the estimated multipath characteristics of the transmission path, a noiseless reception pilot signal and noiseless reception data that are reception signals under noise First noiseless received signal estimating means for estimating a signal, multipath characteristics and transmission of the transmission path from the noiseless received pilot signal and noiseless received data signal estimated by the first noiseless received signal estimating means Second multipath characteristics and transmission data signal estimation means for estimating a data signal, and estimated by the second multipath characteristics and transmission data signal estimation means. And estimating a transmission data signal from the noise-free received data signal.

  According to a tenth aspect of the present invention, in the signal receiving device according to the ninth aspect, the first noiseless received signal estimating means, the second multipath characteristic and the transmission data signal estimating means are configured to receive the received multipath characteristic. The measurement pilot signal and the data signal are processed a plurality of times.

  According to an eleventh aspect of the present invention, in the signal receiving device according to any one of the seventh to tenth aspects, the transmission data signal is a signal having an error correction bit.

  According to a twelfth aspect of the present invention, in the signal receiving device according to any one of the seventh to eleventh aspects, the pilot signal for measuring the multipath characteristic and the transmission data have autocorrelation in a predetermined time range. In addition, there is no cross-correlation within a predetermined time range.

  A thirteenth aspect of the present invention is the signal receiving device according to any one of the seventh to twelfth aspects, wherein the pilot signal for multipath characteristic measurement is transmitted in parallel with the transmission data signal. And

  According to the present invention, it is possible to provide a signal reception method and a signal reception apparatus in wireless communication with a simple configuration that eliminates the effects of external noise, self-multipath interference, and interchannel interference.

(Principle of the present invention)
The principle of the present invention will be described with reference to FIG. 1 illustrating the principle of the present invention.
(1) On the transmission side, a transmission signal 1 including a pilot signal for measuring a multipath characteristic and a transmission data signal is transmitted. The transmitted multipath characteristic measurement pilot signal and transmission data signal each have autocorrelation but no cross-correlation (or low cross-correlation).

  The pilot signal for multipath characteristic measurement may be transmitted before or after the transmission data signal, but transmission data estimation processing is performed by simultaneously transmitting the pilot signal for multipath characteristic measurement with the transmission data signal. Can be performed reliably and quickly.

  It should be noted that the transmitted multipath characteristic measurement pilot signal and transmission data signal may be idealized within a certain range. That is, the multipath characteristic measurement pilot signal and transmission data each have autocorrelation within a predetermined time range, and further have a cross-correlation within the predetermined time range (between the pilot signal and the transmission data signal, between the transmission data signals). Anything without) is acceptable.

Further, since the data of the transmitted pilot signal for measuring the multipath characteristic is notified to the receiving side, the receiving side treats the transmitted pilot signal for measuring the multipath characteristic as known.
(2) On the receiving side, the transmission signal 1 transmitted via the multipath transmission path 2 is received. At the same time, in addition to the transmission signal 1, external noise, self-multipath interference components, and interchannel interference components are also received. For the sake of simplicity, in this specification, external noise and interchannel interference components are collectively referred to as noise. Also, internal noise such as thermal noise is ignored.
(3) As for the received signal 3 received on the receiving side, the transmission signal 1 and noise N affected by the multipath characteristics are received by the multipath transmission path 2.

Received signal 3 = transmitted signal 1 affected by multipath characteristics + noise N (1)
Further, since the transmission signal 1 is composed of a pilot signal and a transmission data signal, the reception signal 3 = a pilot signal affected by the multipath characteristic + a transmission data signal affected by the multipath characteristic + noise N. (2)
It becomes.
(4) The receiver 4 estimates the multipath characteristic and transmission data signal of the transmission path from the received pilot signal for measuring the multipath characteristic in the received signal 3 and the data signal.

  The multipath characteristic of the transmission path is measured based on the autocorrelation result of the pilot signal for measuring the multipath characteristic and the transmission data related to the known pilot signal.

Regarding the received “transmission data signal”, first, based on the estimated multipath characteristic of the transmission path, the influence of the multipath characteristic is removed from the received “transmission data signal” in the reception signal 3, and then The received “transmission data signal” from which the influence of the path characteristic has been removed is subjected to autocorrelation processing to estimate the “transmission data signal”.
(5) The transmission signal 5 estimated from the estimated transmission data signal and the known pilot signal can be obtained.

Estimated transmission signal 5 = estimated transmission data signal + known pilot signal (3)
By the way, from the estimated transmission data signal (a (t): A (ω)) and the estimated multipath characteristic (b (t): B (ω)), the estimated transmission under noiseless reception is received. A data signal (c (t): C (ω)) is obtained by calculation.

That means
c (t) = ∫a (t) b (t−τ) δτ (4)
However, the integration range is −∽ ≦ τ ≦ ∽.
Further, C (ω) = A (ω) × B (ω) (5)
It can also be expressed.

  Similarly, with respect to the pilot signal, the received estimated pilot signal (e (t): E (ω)) without noise is obtained by calculation.

  The no-noise estimated received signal 7 in FIG. 1 is the sum of the received no-noise estimated transmission data signal and the received no-noise estimated pilot signal, and is expressed as follows.

Estimated received signal 7 = c (t) + e (t) (6)
(6) When the noise-free estimated received signal 7 is obtained, the estimated noise N ′ is estimated by the following equation.

Noise N ′ = received signal 3−estimated received signal 7 (7)
Therefore,
Estimated received signal 7 = received signal 3−noise N ′ (8)
As a result, the received signal 7 is a signal obtained by removing the estimated noise N ′ from the received signal 3, and the received signal 7 is a signal having a higher SN ratio than the received signal 3.

  Therefore, if the transmission data is estimated based on the reception signal 7, the transmission data can be estimated more reliably than the transmission data is estimated based on the reception signal 3.

  In this reception method, a multipath characteristic of the transmission path estimated based on a pilot signal for measuring a multipath characteristic is used as an estimation result of transmission data estimated using the estimated multipath characteristic of the transmission path. It can be said that it is corrected by using.

Also, this reception method estimates the multipath characteristics and noise of the transmission path from the received pilot signal for measuring the multipath characteristics and the transmission data signal, and then eliminates the influence of the multipath characteristics of the transmission path. It can also be said that the transmission data signal is estimated based on the received transmission data signal from which the estimated noise is removed.
(7) The receiver 8 estimates the multipath characteristics and estimates the transmission data based on the received signal 7, thereby ensuring more reliable estimation of the multipath characteristics and transmission data than the processing in the receiver 4. Can be estimated.
(8) By repeating the signal processing of FIG. 1B, it is possible to estimate multipath characteristics and transmission data with higher accuracy.

  Note that the signal processing in FIG. 1B ends when the estimated transmission data is converged.

In FIG. 1, the transmission / reception of the signal (A) and the signal processing (B) are performed at substantially the same time. Accordingly, the signal-processed voice or the like of (B) is output almost in real time.
(9) The reason why the estimation of multipath characteristics and the estimation of transmission data are improved by the signal processing of FIG. 1B is that noise is reduced by autocorrelation processing and data determination processing in the receiver 4 and the receiver 8. This is because transmission data is estimated based on the estimated received signal.

If a signal with error correction bits added is used as transmission data, the transmission data can be estimated with higher accuracy.
(Example)
Next, embodiments of the present invention will be described with reference to the drawings. First, a radio communication system in which the present invention is used will be described using the system of FIG.

  2 includes a pilot signal generation unit 9, a transmission data signal generation unit 10, an encoder 11, M-sequence generation units 12 and 13, multipliers 14 to 17, oscillators 18 and 19, an adder 20, and antennas 21 and 31. 32, a pilot signal receiving unit 33, a data signal receiving unit 34, a multipath characteristic measuring unit 35, a multipath removing unit 36, and a data decoding unit 37.

FIG. 2A shows a transmission side device, and FIG. 2B shows a reception side device. In FIG. 2A on the transmission side, the pilot signal (p (t)) generated by the pilot signal generation unit 9 is converted into the M sequence (m ₁ (t ₁ ) generated by the M sequence generation unit 12 by the multiplier 14. )), And then the pilot signal multiplied by the M sequence is further multiplied by the output (f ₁ (t)) of the oscillator 18 by the multiplier 16 and output through the adder 20 and the antenna 21. .

Similarly, an error correction bit is added to the transmission data signal (d (t)) generated by the transmission data signal generation unit 10 by the encoder 11 (d (t) ′), and the M sequence 13 ( m ₂ (t)), and the transmission data signal multiplied by the M sequence generated by the M sequence generation unit 13 is further multiplied by an output (f ₂ (t)) of the oscillator 19 by a multiplier 17. Multiplication is performed and output via the adder 20 and the antenna 21.

Therefore, the signal represented by the following equation is radiated from the antenna 21 as the output of the pilot signal (po (t)) and the output of the transmission data signal (do (t)).
po (t) = p (t) × m ₁ (t) × f ₁ (t) (9)
do (t) = d (t) × m ₂ (t) × f ₂ (t) (10)
m ₁ (t) and m ₂ (t) are signals having autocorrelation and no cross-correlation (or low cross-correlation). F ₁ (t) and f ₂ (t) are carrier frequencies.
In FIG. 2B on the receiving side, the output (po (t)) of the pilot signal radiated from the antenna 21 is received by the antenna 31. A signal received by the antenna 31 is first demodulated by being multiplied by the frequency (f ₁ (t)) in the pilot signal receiving unit 32, and then the M sequence (m ₁ (t)) is output from the demodulated output. And a pilot signal (p (t) ′) affected by noise and multipath is obtained.
From this pilot signal p (t) ′, the multipath characteristic measurement unit 35 estimates the multipath characteristic of the transmission path. Mp (t) represents the multipath characteristic of the transmission path estimated by the multipath characteristic measuring unit 35 on the time axis.
The output (do (t)) of the transmission data signal radiated from the antenna 21 is received by the antenna 32. In the data signal receiving unit 34, first, the frequency (f ₂ (t)) is multiplied and demodulated, and then the demodulated output is subjected to correlation detection with the M sequence (m ₂ (t)) to obtain noise. And a data signal (d (t) ″) affected by the multipath.

  The multipath removal unit 36 applies the data signal d (t) ′ to the data signal d (t) ″ based on the multipath characteristic (mp (t)) estimated by the multipath characteristic measurement unit 35. By removing the influence of the multipath characteristic of the transmission line on “, the data signal d (t) ′ ″ from which the influence of the multipath characteristic is removed is obtained.

  The data decoding unit 37 performs data decoding on the data signal d (t) "" from which the influence of the multipath characteristic has been removed to obtain a data signal d (t) "". With the error correction bit added to the transmission data signal, the error is corrected within the range of the correction capability of the data signal d (t) "" from which the influence of the multipath characteristic has been removed. This data signal d (t) "" "becomes an estimated value of transmission data.

The estimated value d (t) '''' of the transmission data is affected by noise and is not perfect.
(1) Since an error correction code is used, the influence of noise is reduced by error correction.

  (2) Since a signal having autocorrelation is used as transmission data, the influence of noise is reduced in the process of obtaining autocorrelation on the receiving side.

  For this reason, the influence of noise in the reception signal at the antenna (the reception signal in the data signal receiving unit 34) is reduced in the estimated value d (t) "" of the transmission data.

  Similarly, the multipath characteristic (mp (t)) estimated by the multipath characteristic measurement unit 35 is affected by noise and is not perfect, but a signal having autocorrelation is used as a pilot signal. The influence of noise is reduced in the process of taking autocorrelation on the receiving side. Therefore, the influence of noise in the received signal at the antenna (the pilot received signal in the pilot signal receiving unit 33) is reduced in mp (t) that is the output of the multipath characteristic measuring unit 35.

  The embodiment of the present invention will be described with reference to FIG. FIG. 3A schematically shows FIGS. 2A and 2B.

  FIG. 3A shows transmission and reception of a pilot signal and a transmission data signal using an actual communication device, and FIG. 3B is based on the communication result of FIG. Signal processing. Further, the receiver 54 in FIG. 3B performs a process equivalent to that of the receiver 44 in FIG. 3A by simulation.

  A transmission signal 41 in FIG. 3A indicates a pilot signal (po (t)) and a transmission data signal (do (t)) radiated from the antenna 21 in FIG. 3A includes the pilot signal receiving unit 32, the multipath characteristic measuring unit 35, the data signal receiving unit 34, the multipath removing unit 36, and the data decoding unit 37 shown in FIG. Receiver.

  The transmission signal 41 (do (t), po (t)) is received by the antenna on the receiving side under the influence of the multipath transmission line 42 and noise. From the received signal 43 at the antenna, the receiver 44 obtains an estimated value (d (t) '' '') of transmission data and an estimated value (mp (t)) of multipath characteristics.

  FIG. 3B shows signal processing after the transmission / reception processing of the pilot signal and the data signal is performed according to FIG. As the estimated value 51 of the transmission signal in FIG. 3B, the estimated value (d (t) ″ ″) of the transmission data in FIG. 3A is used, and the multipath transmission path in FIG. The estimated value (mp (t)) of the multipath characteristic shown in FIG.

  That is, based on the estimated value (d (t) ″ ″) of the transmission data obtained from FIG. 2 and the estimated value (mp (t)) of the multipath characteristic, the received signal ( RP (t) ′, RD (t) ′) is estimated.

  Since the received signal at this antenna is estimated based on the estimated value (d (t) ″ ″) of the transmission data and the estimated value (mp (t)) of the multipath characteristic, it is estimated without noise. Received signal 53.

  Simulation processing is performed on the estimated received signal without noise. The contents of the simulation process will be described below.

  The estimated noise-free received signals (RP (t) ′, RD (t) ′) are supplied to the receiver 54 having the same function as the receiver 44 in FIG. An estimated value of data (d (t) ′ ″ ″) and an estimated value of multipath characteristics (mp (t) ′) are obtained.

  As a result, it is possible to obtain from the receiver 54 an estimated value of transmission data with reduced multipath and noise effects and an estimated value of multipath characteristics.

  Here, the estimated value (d (t) ″ ″) of the transmission data and the estimated value (mp (t) ′) of the multipath characteristic are the estimated value (d (t) ″ ″) of the transmission data. ) And the estimated value (mp (t)) of the multipath characteristic, it will be explained that the influence of noise is reduced.

The received signal RP (t) of the pilot signal at the antenna in FIG. 3A is expressed by the following equation (9), where MP (t) is the multipath characteristic and N (t) is the noise. t) = ∫do (t) · MP (t−τ) δτ + N (t) (11)
However, the integration range is −∽ ≦ τ ≦ ∽.
Similarly, the received signal RD (t) of the data signal at the receiving antenna in FIG. 3A is expressed by the following equation (10): RD (t) = ∫ro (t) · MP (t−τ) δτ + N (t) (12)
However, the integration range is −∽ ≦ τ ≦ ∽.
Further, the estimated received signals (RP (t) ′, RD (t) ′) of the pilot signal and the data signal at the receiving antenna in FIG. 3B are estimated values (d (t) ″ ″) of the transmission data. ) And the estimated value (mp (t)) of the multipath characteristic.

That is, the estimated received signal (RP (t) ′) at the antenna of the pilot signal receiver is assumed to be known on the receiving side if the transmitted pilot signal 9 is known.
RP (t) ′ = ∫p (t) · mp (t−τ) δτ (13)
Although mp (t) itself is partially affected by noise, Equation (12) itself is a received signal without noise because there is no noise term. Therefore, RP (t) ′ has a reduced influence of noise compared to RP (t).

  Next, from this pilot signal RP (t) ', the multipath characteristic measurement unit 35 estimates the multipath characteristic of the transmission path. The multipath characteristic of the transmission path estimated by the multipath characteristic measurement unit 35 is expressed on the time axis as mp (t) ′.

  Since a signal having autocorrelation is used as a pilot signal, the influence of noise is reduced in the process of taking the autocorrelation on the receiving side, and as a result, mp (t) ′ is there.

Similarly, the estimated received signal (RD (t) ′) at the antenna of the receiver of the data signal is
RD (t) ′ = ∫d (t) ″ ″ · mp (t−τ) δτ (14)
Although d (t) ″ ″ and mp (t) themselves are partially affected by noise, it can be said that there is no noise term and the received signal is noiseless. Therefore, RD (t) ′ has a reduced influence of noise compared to RD (t).

  Next, the multipath removal unit 36 performs the data signal RD (t) on the data signal RD (t) ′ based on the multipath characteristic (mp (t) ′) estimated by the multipath characteristic measurement unit 35. ) ′ To remove the influence of the multipath characteristic of the transmission path and obtain a data signal from which the influence of the multipath characteristic is removed. Further, the data decoding unit 37 performs data decoding on the data signal from which the influence of the multipath characteristic is removed, and obtains a data signal d (t) "" "".

  As described above, the influence of noise on the data signal d (t) "" "" is reduced with respect to the data signal RD (t) '.

  Further, by repeating the process of FIG. 3B, it is possible to obtain from the receiver 54 an estimated value of transmission data and an estimated value of multipath characteristics in which the influence of multipath and noise is further reduced. .

  A method for reducing the influence of noise in wireless communication will be described with reference to FIG.

  Step S10: A pilot signal having autocorrelation for measuring multipath characteristics and a data signal having autocorrelation and having error correction bits are transmitted.

  Step S11: The pilot signal and data signal transmitted in step S10 are received via the transmission path.

  Step S12: The multipath characteristic of the transmission path is estimated from the pilot signal received in step S11.

  Step S13: A transmission data signal is estimated from the data signal received in step S11 using the estimated multipath characteristic of the transmission path estimated in step S12.

  Step S14: The data signal received in the reception step is estimated using the estimated transmission data signal estimated in Step S13 and the estimated multipath characteristic of the transmission path estimated in Step S12.

  Step S15: The pilot signal received in step S11 is estimated using the pilot signal transmitted in step S10 and the estimated multipath characteristic of the transmission path estimated in step S12.

  Step S16: Multipath characteristics of the transmission path are estimated from the pilot signal estimated in step S15.

  Step S17: A transmission data signal is estimated from the data signal estimated at step S14 using the estimated multipath characteristic of the transmission path estimated at the previous step S16.

  A signal without error correction bits may be used.

  Thereby, the influence of the noise in radio | wireless communication can be reduced.

  Further, following FIG. 4, as shown in FIG. 5, the process of FIG. 3B may be repeated.

  Step S20: The reception data signal received in step S11 is estimated using the estimated transmission data signal estimated in step S17 and the estimated multipath characteristic of the transmission path estimated in step S16.

  Step S21: The pilot signal received in step S11 is estimated using the pilot signal transmitted in step S10 and the estimated multipath characteristic of the transmission path estimated in step S16.

  Step S22: Multipath characteristics of the transmission path are estimated from the pilot signal estimated in step S21.

  Step S23: A transmission data signal is estimated from the data signal estimated at step S20 using the estimated multipath characteristic of the transmission path estimated at step S22.

  Thereby, the influence of noise in wireless communication can be further reduced.

  In the above description, the M sequence is used. However, a signal other than the M sequence may be used as long as the signal has autocorrelation and can be cross-correlated with other signals within a predetermined range. Good.

  In the above description, one series of signals has been described as the data signal. However, a plurality of series may be used as long as the signals have autocorrelation and the cross-correlation with other signals can be ignored within a predetermined range. The signal may also be

It is a principle explanatory view of the present invention. It is a figure for demonstrating the transmission side apparatus of this invention. It is a figure for demonstrating embodiment of this invention. It is FIG. (1) for demonstrating the flow of a process of the noise reduction method in radio | wireless communication. It is FIG. (2) for demonstrating the flow of a process of the noise reduction method in radio | wireless communication.

Explanation of symbols

1, 41 Transmission signal 2, 42 Multipath transmission path 3 Reception signal 4, 8, 44, 54 Receiver 5 Estimated transmission signal 6, 52 Estimated multipath transmission path 7, 53 Noise-free estimation reception signal 9 Pilot signal generator 10 Transmission data signal generator 11 Encoder 12, 13 M sequence generator 14-17 Multiplier 18, 19 Oscillator 20 Adder 21, 31, 32 Antenna 33 Pilot signal receiver 34 Data signal receiver 35 Multi Path characteristic measurement unit 36 Multipath removal unit 37 Data decoding unit 43 Received signal at antenna 51 Estimated value of transmission signal

Claims (13)

In a signal reception method for receiving a pilot signal and a transmission data signal for measuring a multipath characteristic via a transmission path,
The multipath characteristic of the transmission path estimated based on the pilot signal for multipath characteristic measurement is
A signal receiving method, wherein correction is performed using an estimation result of transmission data estimated using the estimated multipath characteristic of the transmission path. In a signal reception method for receiving a pilot signal and a transmission data signal for measuring a multipath characteristic via a transmission path,
From the received multipath characteristic measurement pilot signal and transmission data signal, estimate the multipath characteristic and noise of the transmission path,
Then, the transmission data signal is estimated based on the received transmission data signal from which the influence of the multipath characteristic of the transmission path is eliminated and the estimated noise is removed. A first multipath characteristic and transmission data signal estimation step of receiving a pilot signal and a transmission data signal for multipath characteristic measurement via a transmission line and estimating the multipath characteristic and transmission data signal of the transmission line When,
A first noiseless received signal estimation for estimating a noiseless received pilot signal and a noiseless received data signal, which are received signals without noise, using the estimated transmission data signal and the estimated multipath characteristic of the transmission path. Steps,
Second multipath characteristic and transmission data signal for estimating the multipath characteristic and transmission data signal of the transmission path from the noiseless reception pilot signal and noiseless reception data signal estimated by the first noiseless reception signal estimation step An estimation step,
After repeating the first noiseless received signal estimation step and the second multipath characteristic and transmission data signal estimation step N (N is a natural number of 1 or more) times,
A signal receiving method, wherein a transmission data signal is estimated from an estimated no-noise reception data signal.   4. The signal receiving method according to claim 1, wherein the transmission data signal is a signal having error correction bits.   5. The multipath characteristic measurement pilot signal and the transmission data have autocorrelation in a predetermined time range and further have no cross-correlation in a predetermined time range. A signal receiving method according to claim 1.   6. The signal reception method according to claim 1, wherein the pilot signal for measuring the multipath characteristic is transmitted in parallel with the transmission data signal. In a signal receiving apparatus that receives a pilot signal for transmission of multipath characteristics and a transmission data signal via a transmission line,
Multipath characteristic measuring means for estimating the multipath characteristic of the transmission path based on a pilot signal for multipath characteristic measurement;
Transmission data estimation means for estimating transmission data using the multipath characteristics estimated by the multipath characteristic measurement means;
A signal receiving apparatus, wherein multipath characteristics are corrected using transmission data estimated by the transmission data estimation means. In a signal receiving apparatus that receives a pilot signal for transmission of multipath characteristics and a transmission data signal via a transmission line,
Means for estimating the multipath characteristics and noise of the transmission path from the received pilot signal for measuring the multipath characteristics and the transmission data signal;
Means for estimating the transmission data signal based on the received data signal from which the influence of the multipath characteristic of the transmission path is eliminated and the estimated noise is removed. apparatus. First multipath characteristic and transmission data signal estimation means for receiving a pilot signal and a transmission data signal for multipath characteristic measurement via a transmission line and estimating the multipath characteristic and transmission data signal of the transmission line When,
A first noiseless received signal estimation for estimating a noiseless received pilot signal and a noiseless received data signal, which are received signals without noise, using the estimated transmission data signal and the estimated multipath characteristic of the transmission path. Means,
Second multipath characteristic and transmission data signal for estimating the multipath characteristic and transmission data signal of the transmission path from the noiseless reception pilot signal and noiseless reception data signal estimated by the first noiseless reception signal estimation means An estimation means,
A signal receiving apparatus for estimating a transmission data signal from a second multipath characteristic and a noiseless reception data signal estimated by a transmission data signal estimation means.   The first noiseless reception signal estimation means and the second multipath characteristic / transmission data signal estimation means process the received multipath characteristic measurement pilot signal and data signal a plurality of times. The signal receiving apparatus according to claim 9.   The signal receiving apparatus according to claim 7, wherein the transmission data signal is a signal having an error correction bit.   12. The multipath characteristic measurement pilot signal and the transmission data have autocorrelation in a predetermined time range and further have no cross-correlation in a predetermined time range. The signal receiving device according to claim 1. 13. The signal receiving apparatus according to claim 7, wherein the multipath characteristic measurement pilot signal is transmitted in parallel with the transmission data signal.

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