JP2004088767A - Transmitter and receiver using space-time transmission diversity multi-carrier CDMA system, and wireless communication system including transmitter and receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the hardware scale of STTD even when the number of subcarriers of MC-CDMA increases, and to realize a transmission device and a reception device of the MC-CDMA system which can be realized with a small hardware scale, and transmission thereof. Provided is a wireless communication system including a device and a receiving device.
A receiving apparatus includes a plurality of receiving antennas, and a plurality of MCs for performing serial / parallel conversion, fast Fourier transform, despreading, equalization, and combining for respective reception signals of the plurality of reception antennas. A CDMA receiving means, a spatio-temporal decoding means for decoding the output signals of the plurality of MC-CDMA receiving means in the time direction and the spatial direction, and a parallel / serial conversion means for converting the output signal of the spatio-temporal decoding means into a serial signal. A serial conversion means, a demapping means for demodulating an output signal of the parallel / serial conversion means, and a decoding / deinterleaving means for deinterleaving the output signal of the demapping means and performing error correction decoding; Restore the transmitted data.
[Selection diagram] Fig. 4

Description

<< The present invention relates to a transmitting apparatus and a receiving apparatus based on MC-CDMA (Multicarrier-Division \ Multiple \ Access) method, and a wireless communication system including these transmitting apparatus and receiving apparatus.

無線 A wireless communication system that performs high-speed transmission is easily affected by multipath fading, and the quality of a wireless link is likely to deteriorate. For this reason, it has been proposed to use an MC-CDMA scheme having resistance to multipath interference (MPI: Multi Path Interference) caused by multipath in such a wireless transmission system (for example, Non-Patent Document 1). . This MC-CDMA system is effective for realizing broadband wireless transmission.

FIGS. 1 and 2 are block diagrams schematically illustrating a functional configuration of a conventional MC-CDMA transmitting apparatus and receiving apparatus.

As shown in FIG. 1, transmitting apparatus 1 includes encoding / interleaving section 11 for performing error correction coding on a transmission data sequence and further performing interleaving, mapping section 12, MC-CDMA transmitting section 13, and transmitting antenna 14. are doing.

In the MC-CDMA transmission unit 13, the data series input from the mapping unit 12 is subjected to serial / parallel conversion by a serial / parallel (S / P) conversion unit 131. As a result, consecutive Nc / SF symbols are converted into a parallel data sequence. Here, the integer Nc represents the number of points of FFT / IFFT, and the integer SF is a divisor of Nc.

Next, the copy unit 132 performs SF copies for each symbol.

Next, spreading section 133 _performs multiplication of spreading sequences C _i1 , C _i2 ,..., C _iSF (C _ij {−1, 1}) for each of the SF copied symbols. Here, i is a user number.

Next, a total of Nc symbols multiplied by the inverse fast Fourier transform (IFFT) unit 134 are converted into time-axis data.

Next, parallel / serial conversion is performed by the parallel / serial (P / S) conversion unit 135, and a guard interval is added by the guard interval (GI) addition unit 136. The guard interval is used to avoid inter-symbol interference due to a delayed wave.

受 信 As shown in FIG. 2, receiving apparatus 2 includes receiving antenna 21, MC-CDMA receiving section 22, demapping section 23, and decoding / deinterleaving section 24.

In the MC-CDMA receiver 22, first, a guard interval is removed from the received signal by a guard interval remover 221.

Next, the serial signal is converted into parallel by the serial / parallel converter 222.

Next, the data on the time axis is converted into the data on the frequency axis by the fast Fourier transform (FFT) unit 223.

Next, despreading section 224 multiplies despreading sequences C _i1 , C _i2 ,..., C _iSF (C _ij {−1, 1}) having the same pattern as the spreading sequence used in the transmission section.

Next, the channel estimation unit 227 outputs a channel estimation value for each subcarrier obtained from a known signal such as a preamble signal or a pilot subcarrier.

Next, the channel distortion of each subcarrier is compensated and combined by the equalizer / combiner 225 using the channel estimation value from the channel estimator 227. Then, the combined symbol is subjected to parallel / serial conversion by the parallel / serial conversion unit 226.

(4) Finally, all symbols are demodulated in the demapping unit 23, the decoding / deinterleaving unit 24 decodes the error correction code, and the received data sequence is extracted.

S. Hara, R .; Prasad, "Overview of Multicarrier CDMA", IEEE Commun. {Mag. , {Pp. 126-144, {Dec. 1997

However, in the MC-CDMA system, multi-path separation by a rake receiver, which is an advantage of a spread spectrum system such as DS-CDMA (Direct @ Sequence @ CDMA), cannot be performed. Therefore, path diversity that can be obtained in the DS-CDMA system is not possible. There was a problem that the effect was not obtained and the characteristics were deteriorated. Further, in the MC-CDMA system, the same symbol is copied to a plurality of subcarriers and transmitted, so that a frequency diversity effect can be expected. However, if the correlation between the subcarriers is large, the frequency diversity effect is deteriorated. was there.

Therefore, an object of the present invention is to provide a transmission apparatus and a reception apparatus of the MC-CDMA system, which can improve characteristics by applying space-time transmission diversity (STTD: Space \ Transmit \ Diversity), and a transmission apparatus and a reception apparatus thereof. The present invention provides a wireless communication system including:

Another object of the present invention is to provide a transmission apparatus of the MC-CDMA system that can be realized with a small hardware scale without increasing the hardware scale of the STTD even when the number of MC-CDMA subcarriers increases. An object of the present invention is to provide a receiving device and a wireless communication system including the transmitting device and the receiving device.

According to the present invention, encoding and interleaving means for performing error correction coding and interleaving of transmission data, mapping means for arranging an output signal of the encoding and interleaving means at a signal point on a complex plane, and outputting an output signal of the mapping means at Nc / Serial / parallel conversion means for converting to SF parallel signals (where Nc is an integer representing the number of points of inverse fast Fourier transform, SF is an integer which is a divisor of Nc), and output from the serial / parallel conversion means Nc / SF space-time coding means for performing coding in the time direction and space direction on the parallel signal, and a plurality of signals output from the Nc / SF space-time coding means, respectively, in parallel. SF copies, spreads, performs Nc point inverse fast Fourier transform, then parallel / serial A transmission apparatus using a space-time transmission diversity MC-CDMA system including a plurality of MC-CDMA transmission units configured to perform conversion and a plurality of transmission antennas for transmitting output signals of the plurality of MC-CDMA transmission units, respectively. Provided.

According to the present invention, further, a plurality of receiving antennas and a plurality of MCs for performing serial / parallel conversion, fast Fourier transform, despreading, equalization and synthesis for received signals of the plurality of receiving antennas, respectively. A CDMA receiving means, a spatio-temporal decoding means for decoding the output signals of the plurality of MC-CDMA receiving means in the time direction and the spatial direction, and a parallel / serial conversion means for converting the output signal of the spatio-temporal decoding means into a serial signal. A serial conversion means, a demapping means for demodulating an output signal of the parallel / serial conversion means, and a decoding / deinterleaving means for deinterleaving the output signal of the demapping means and performing error correction decoding; Provided by a space-time transmission diversity MC-CDMA scheme for restoring transmitted data That.

According to the present invention, there is further provided a wireless communication system including the transmitting device and the receiving device.

It is preferable that the plurality of MC-CDMA transmission units are configured to add a guard interval to each of the parallel / serial converted signals.

Each of the plurality of MC-CDMA transmitting units includes Nc / SF copying units for copying SFc signals in parallel with Nc / SF space-time coding units, and Nc / SF copying units. Spreading means for multiplying the output by a spreading code to spread the output; Nc-point inverse fast Fourier transform means for performing an inverse fast Fourier transform on the output of the spreading means; and parallel / serial for parallel / serial conversion of the output of the inverse fast Fourier transform means. It is preferable that the apparatus further comprises a conversion means and a guard interval means for adding a guard interval to the output of the parallel / serial conversion means.

It is also preferable that the plurality of MC-CDMA receiving units are configured to remove guard intervals from received signals.

It is preferable that each of the plurality of MC-CDMA receiving units is configured to estimate a propagation path for each subcarrier, and perform equalization and combining from the estimated propagation path.

A plurality of MC-CDMA receiving units each for removing a guard interval from a received signal, a serial / parallel converting unit for serial / parallel converting an output of the guard interval removing unit, and a serial / parallel converting unit Fast Fourier transform means for performing fast Fourier transform on the output of, despreading means for multiplying the output of the fast Fourier transform means by the same spreading code as on the transmitting side and despreading, and channel estimation for estimating the channel for each subcarrier It is also preferable that the apparatus further comprises an equalizing / combining means for performing equalization and combining of the output of the despreading means from the estimated propagation path.

Each of the plurality of MC-CDMA receiving units further includes an estimated value combining unit that combines the channel estimation values estimated by the channel estimating unit, and the spatio-temporal decoding unit uses the combined channel estimation values. It is also preferable that the decoding device is configured to perform the decoding.

It is also preferred that the spreading code is a Walsh Hadamard code.

According to the transmitting apparatus and receiving apparatus of the MC-CDMA system to which the space-time transmission diversity system in the present invention is applied, under a multipath fading environment, the frequency diversity effect of MC-CDMA and the antenna diversity effect from STTD are simultaneously performed. With this, the line quality and transmission characteristics of the wireless link are improved, and higher speed and higher quality broadband wireless access transmission can be realized.

That is, in the present invention, transmission data encoded in a time direction and a space direction are transmitted from a plurality of transmission antennas, and the codes are decoded on the reception side, so that signals between the antennas can be separated, and antenna diversity can be achieved. The effect is obtained. Further, since a frequency diversity effect, which is a feature of MC-CDMA, can be obtained, transmission characteristics can be improved even in a severe fading environment.

The present invention is also effective for an increase in the hardware scale of space-time transmission diversity, which occurs when the number of MC-CDMA subcarriers increases. In general, space-time decoding uses a channel estimation value, so it is necessary to perform space-time decoding for each estimated propagation characteristic, and therefore basically needs to perform it for each subcarrier. However, according to the present invention, after equalization and combination, spatio-temporal decoding is performed using the channel estimation value combined by the same method as the combining method, so that the hardware scale related to space-time decoding Can always be realized by 1 / SF. This effect is particularly effective when the number of subcarriers is large.

FIGS. 3 and 4 are block diagrams schematically illustrating the functional configuration of the transmission device and the reception device of the MC-CDMA system according to the preferred embodiment of the present invention.

In the present invention, a space-time transmission diversity (STTD) technology is applied to the MC-CDMA system. STTD is an anti-fading countermeasure technique, in which the transmitting side transmits space-time coded signals from a plurality of antennas, and the receiving side obtains diversity by separating and combining signals transmitted from each antenna. In the STTD system itself, in an environment where the fading correlation between the antennas is high, the BER characteristic is degraded due to the weak effect of the antenna diversity.

As shown in FIG. 3, transmitting apparatus 3 includes an encoding / interleaving section 31 that performs error correction coding on a transmission data sequence and further performs interleaving, a mapping section 32, a serial / parallel (S / P) conversion section 33, an Nc / SF (where Nc is an integer representing the number of IFFT points, SF is an integer which is a divisor of Nc) space-time coding (STTD encoder) unit 34 and M (where M is an integer of 2 or more) MC-CDMA transmitting units 35-1 to 35-M and M transmitting antennas 36-1 to 36-M.

Each of MC-CDMA transmitting sections 35-1 to 35-M includes Nc / SF copy sections 352, spreading section 353, inverse fast Fourier transform (IFFT) section 354, and parallel / serial (P / S). It has a conversion unit 355 and a guard interval (GI) unit 356.

The transmission data sequence input to the transmission device 3 is error-correction-coded in the encoding interleave unit 31 and further interleaved, input to the mapping unit 32, and mapped to signal points on a complex plane.

Next, the serial / parallel conversion unit 33 converts the symbol sequence into Nc / SF parallel symbol sequences.

計 A total of Nc / SF parallel symbol sequences output from the serial / parallel conversion unit 33 are input to the STTD encoder unit 34 in units of consecutive N symbols (where N is an integer of 2 or more).

Each of the STTD encoder units 34 performs STTD encoding on an input signal of N consecutive symbols, and outputs a signal of N symbols in the time direction and M symbols in the spatial direction.

Next, the M symbols in the spatial direction, which are the outputs of the STTD encoder units 34, are input to the M MC-CDMA transmission units 35-1 to 35-M.

Next, in each of the MC-CDMA transmitting sections 35-1 to 35-M, the input parallel data sequence is copied by the copying section 352 into SF parallel signals.

Next, the spreading section 353 multiplies the spreading codes C _i1 , C _i2 ,..., C _iSF (C _ij {−1, 1}). As a spreading code, a Walsh Hadamard code or the like can be used.

The signal multiplied by the spread code is converted into the value of each sample point in the time domain by the inverse fast Fourier transform unit 354 of Nc points.

Next, after parallel / serial conversion is performed by the parallel / serial conversion unit 355, and a guard interval is added by the GI unit 356, the signals are simultaneously transmitted by different antennas 36-1 to 36-M. The guard interval is used to avoid intersymbol interference due to a delayed wave.

As shown in FIG. 4, receiving apparatus 4 includes L (L is an integer equal to or greater than 2) receiving antennas 41-1 to 41-L and L MC-CDMA receiving units 42-1 to 42-L. L, Nc / SF (where Nc is an integer representing the number of FFT points, SF is an integer which is a divisor of Nc) space-time decoding (STTD decoder) section 43, and parallel / serial conversion section 44 , A demapping unit 45, and a decoding / deinterleaving unit 46.

Each of MC-CDMA receiving sections 42-1 to 42-L includes a guard interval removing section (-GI) 421, a serial / parallel converting section 422, a fast Fourier transform (FFT) section 423, and a despreading section 424. , Nc / SF equalizers / combiners 425, propagation path estimators 427, and estimated value combiners 428.

In the receiving device 4, signals received by the plurality of receiving antennas 41-1 to 41-L are processed by different MC-CDMA receiving units 42-1 to 42-L, respectively.

In each of the MC-CDMA receiving units 42-1 to 42-L, the received signal is first applied to the guard interval removing unit 421 to remove the guard interval, and the serial / parallel converting unit 422 outputs Nc parallel signals. Converted to a signal.

Next, these parallel signals are converted into signals of each subcarrier in the frequency domain by the fast Fourier transform unit 423 of Nc points.

Next, the converted signal is multiplied by a spreading code for each SF subcarriers in despreading section 424. Here, as the code to be multiplied, the same C _i1 , C _i2 ,..., C _iSF (C _ij {-1, 1}) as the spreading code used in the transmission device 3 is used.

Next, in the equalizer / combiner 425, the signal for each subcarrier is equalized using the channel estimation value for each subcarrier, and SF signals after equalization are combined. Here, as the combining method, any method such as equal gain combining or MMSEC (Minimum Mean Square Error Combining) can be used.

伝 搬 The propagation path estimation value for each subcarrier is estimated by the propagation path estimator 427 using a known signal such as a preamble signal added to the head of a transmission frame or a pilot subcarrier inserted between data subcarriers. The estimated value combiner 428 combines the propagation path estimation value for each subcarrier estimated by the propagation path estimator 427 in the same unit (SF number) as the equalizer / combiner 425 using the same combining method. Then, the data is output to the STTD decoder 43.

The parallel signal output from the equalizer / combiner 425 of the L MC-CDMA receivers 42-1 to 42-L is input to the STTD decoder 43. The STTD decoder unit 43 performs STTD decoding on the signal of L symbols in the spatial direction and N symbols in the time direction using the propagation path estimation value from the estimation value combiner 428, and outputs serial data of N symbols in the time direction. Is output.

This data is subjected to parallel / serial conversion in a parallel / serial conversion unit 44, and thereafter, all symbols are demodulated in a demapping unit 45, deinterleaved in a decoding / deinterleave unit 46, and then subjected to error correction codes. Decoding processing is performed, and a received data sequence is extracted.

FIG. 5 is a diagram illustrating the principle of STTD when N = 2, M = 2, and L = 1. For the sake of simplicity, the principle of STTD will be described taking this condition as an example. Here, * represents a complex conjugate.

Transmit diversity is a Closed Loop type that generally performs antenna selection and phase control based on feedback information. However, in the present invention, an Open @ Loop type that does not use feedback information is applied, and a transmission diversity system is used in which a transmitting device transmits with a plurality of antennas and a receiving device separates and combines received signals.

According to FIG. 5, the data input to the STTD encoder unit is processed in units of two symbols. In the first time symbol, S ₀ is transmitted from transmission antenna # 1 and −S ₁ ^* is transmitted from transmission antenna # 2. In the next time symbols, S ₁ is transmitted from the transmission antenna # 1, S ₀ ^* is transmitted from the transmission antenna # 2. Then, it is spread on the frequency axis for each subcarrier and transmitted.

Table 1 shows transmission symbol patterns when two transmission antennas are used. Here, C _{i, j} represents a spreading code whose chip length is SF for all i.

FIG. 6 is a block diagram schematically illustrating the principle configuration of the STTD receiver according to the present invention.

On the receiving side of STTD, assuming that the fluctuation of the propagation path characteristics is moderate (that is, the propagation path does not fluctuate in two consecutive time slots), the propagation path and transmission of the signal arriving from transmitting antenna # 1 are assumed. The propagation path of the signal arriving from antenna # 2 can be represented by the following equations (1) and (2), respectively. Here, j = 1, 2,..., N.

The received signal is represented by the following equations (3) and (4). Here, i = 1, 2,..., Nc / SF, n ₀ and n ₁ are complex random variables including noise and interference components, and r ₀ and r ₁ are received signals in time slots t and t + T. .

At this time, the two time slot signals received by the receiving antenna are given by the following equation after all the subcarrier signals are despread.

信号 The combined signal can be expressed by the following equations (9) and (10), respectively.

Each STTD decoder unit 43 includes a received data combiner 431 and a maximum likelihood estimator (MLD) 432. The output signals S ₀ ′ and S ₁ ′ from the received data combiner 431 are represented by the following equations (11) and (12).

Maximum likelihood estimator 432 uses output signals S ₀ ′ and S ₁ ′ from received data combiner 431 and output signals h ₀ and h ₁ of estimated value combiner 428 according to the present invention to transmit data S _0. and to restore the _{S 1.}

Note that, in this principle configuration, a configuration having two transmitting antennas and one receiving antenna has been described. However, it is easy to extend the configuration to M transmitting antennas and L receiving antennas as shown in FIGS. It is feasible.

The embodiments described above are merely examples of the present invention, and do not limit the present invention. The present invention can be embodied in various other modified forms and modified forms. Therefore, the scope of the present invention is defined only by the appended claims and their equivalents.

FIG. 9 is a block diagram schematically illustrating a functional configuration of a conventional MC-CDMA transmission device. FIG. 10 is a block diagram schematically illustrating a functional configuration of a conventional MC-CDMA receiving device. FIG. 2 is a block diagram schematically illustrating a functional configuration of an MC-CDMA transmission device of the present invention. FIG. 2 is a block diagram schematically illustrating a functional configuration of an MC-CDMA receiving apparatus of the present invention. FIG. 3 is a diagram illustrating the principle of the STTD method. FIG. 2 is a block diagram schematically illustrating a principle configuration of an STTD receiving apparatus according to the present invention.

Explanation of reference numerals

3 Transmitting Device 4 Receiving Device 31 Encoding / Interleaving Unit 32 Mapping Unit 33 Serial / Parallel (S / P) Conversion Unit 34 Space-Time Coding (STTD Encoder) Units 35-1 to 35-M MC-CDMA Transmitting Unit 36-1 36-M transmitting antennas 41-1 to 41-L receiving antennas 42-1 to 42-L MC-CDMA receiving unit 43 space-time decoding (STTD decoder) unit 44 parallel / serial (P / S) converting unit 45 demapping Section 46 decoding / deinterleaving section 352 copying section 353 spreading section 354 inverse fast Fourier transform (IFFT) section 355 parallel / serial (P / S) converting section 356 guard interval (GI) section 421 guard interval removing (GI) section 422 Serial / parallel (S / P) converter 4 3 Fast Fourier transform (FFT) unit 424 inverse spreading part 425 equalizer, synthesizer 427 channel estimator 428 estimates the synthesizer 431 receives data synthesizer 432 maximum likelihood estimator (MLD)

Claims (18)

Encoding / interleaving means for performing error correction coding and interleaving of transmission data; mapping means for arranging output signals of the encoding / interleaving means at signal points on a complex plane; and Nc / SF output signals of the mapping means (where , Nc is an integer representing the number of points of the inverse fast Fourier transform, SF is an integer which is a divisor of Nc), and a serial / parallel conversion means for converting the signal into a parallel signal, and a parallel signal output from the serial / parallel conversion means. On the other hand, Nc / SF number of space-time coding means for performing coding in the time direction and space direction and a plurality of signals output from the Nc / SF number of space-time coding means, Copy, spread, perform Nc point inverse fast Fourier transform, then parallel / serial convert Space-time transmission diversity multi-carrier CDMA system, comprising: a plurality of multi-carrier CDMA transmission means configured as described above; and a plurality of transmission antennas for respectively transmitting output signals of the plurality of multi-carrier CDMA transmission means. By transmitting device. The transmission apparatus according to claim 1, wherein the plurality of multicarrier CDMA transmission units are configured to add a guard interval to each of the parallel / serial converted signals. Each of the plurality of multi-carrier CDMA transmitting units is configured to copy Nc / SF signals in parallel with the Nc / SF space-time coding units, and to copy the Nc / SF signals. Spreading means for multiplying the output of the copying means by a spreading code for spreading; an inverse fast Fourier transform means of Nc points for performing an inverse fast Fourier transform of the output of the spreading means; and a parallel / serial output of the inverse fast Fourier transform means. 3. The transmitting apparatus according to claim 1, further comprising: a parallel / serial conversion unit for performing conversion; and a guard interval unit for adding a guard interval to an output of the parallel / serial conversion unit. 4. The transmitting apparatus according to claim 3, wherein the spreading code is a Walsh Hadamard code. A plurality of receiving antennas; a plurality of multi-carrier CDMA receiving means for performing serial / parallel conversion, fast Fourier transform, despreading, equalization, and combining for each of the reception signals of the plurality of reception antennas; Space-time decoding means for decoding the output signals of the plurality of multi-carrier CDMA reception means in the time direction and the space direction, parallel / serial conversion means for converting the output signals of the space-time decoding means into serial signals, A demapping means for demodulating an output signal of the parallel / serial conversion means; and a decoding / deinterleaving means for deinterleaving and error correcting and decoding the output signal of the demapping means. -Time transmission diversity multi-carrier CDMA characterized by recovering Reception by the formula apparatus. The receiving apparatus according to claim 5, wherein the plurality of multi-carrier CDMA receiving units are configured to remove guard intervals from received signals. 7. The method according to claim 5, wherein each of the plurality of multi-carrier CDMA receiving units estimates a propagation path for each subcarrier, and performs equalization and combining from the estimated propagation path. The receiving device according to the above. Each of the plurality of multi-carrier CDMA receiving means for removing a guard interval from a received signal; a serial / parallel converting means for serial / parallel converting an output of the guard interval removing means; Fast Fourier transform means for fast Fourier transforming the output of the parallel transform means, despreading means for multiplying the output of the fast Fourier transform means by the same spreading code as on the transmitting side to despread, and estimating the propagation path for each subcarrier 8. An apparatus according to claim 5, further comprising an equalizing / combining means for equalizing and synthesizing an output of said despreading means from said estimated propagation path. The receiving device according to the paragraph. Each of the plurality of multi-carrier CDMA receiving units further includes an estimated value combining unit that combines the channel estimation values estimated by the channel estimating unit, and the spatio-temporal decoding unit includes: 9. The receiving apparatus according to claim 8, wherein the decoding is performed using an estimated value. The receiving apparatus according to claim 8 or 9, wherein the spread code is a Walsh Hadamard code. Encoding and interleaving means for error-correcting and encoding one transmission data and interleaving; mapping means for arranging output signals of the encoding and interleaving means at signal points on a complex plane; (Where Nc is an integer representing the number of points of the inverse fast Fourier transform, SF is an integer that is a divisor of Nc) and a parallel / parallel conversion means for converting the signal into a parallel signal, and a parallel signal output from the serial / parallel conversion means. Nc / SF number of space-time coding means for coding the signal in the time direction and space direction, and a plurality of signals output from the Nc / SF number of space-time coding means, respectively. SF copies, spreads, performs Nc point inverse fast Fourier transform, then parallel / serial conversion A multi-carrier CDMA transmission means comprising: a plurality of multi-carrier CDMA transmission means configured to perform transmission and a plurality of transmission antennas respectively transmitting output signals of the plurality of multi-carrier CDMA transmission means; ,
A plurality of receiving antennas; a plurality of multi-carrier CDMA receiving means for performing serial / parallel conversion, fast Fourier transform, despreading, equalization, and combining for each of the reception signals of the plurality of reception antennas; Space-time decoding means for decoding the output signals of the plurality of multi-carrier CDMA reception means in the time direction and the space direction, parallel / serial conversion means for converting the output signals of the space-time decoding means into serial signals, A demapping means for demodulating an output signal of the parallel / serial conversion means, and a decoding / deinterleaving means for deinterleaving and error correction decoding of the output signal of the demapping means. Space-time transmission diversity for restoring transmission data Wireless communication system characterized by comprising a device. The wireless communication system according to claim 11, wherein the plurality of multi-carrier CDMA transmission means in the transmission device are configured to add a guard interval to each of the parallel / serial converted signals. Each of the plurality of multi-carrier CDMA transmitting units in the transmitting apparatus is configured to copy Nc / SF signals in parallel with Nc / SF number of signals input from the Nc / SF space-time coding units; Spreading means for multiplying the output of the / SF copying means by a spreading code, spreading the output of the spreading means by inverse fast Fourier transform at Nc points, and the output of the inverse fast Fourier transform means 13. The wireless communication according to claim 11, further comprising: a parallel / serial conversion unit for performing parallel / serial conversion of the data; and a guard interval unit for adding a guard interval to an output of the parallel / serial conversion unit. system. The wireless communication according to any one of claims 11 to 13, wherein the plurality of multi-carrier CDMA receiving units in the receiving device are configured to remove guard intervals from received signals, respectively. system. The multi-carrier CDMA receiving unit in the receiving device is configured to estimate a propagation path for each subcarrier and perform equalization and combining from the estimated propagation path. 15. The wireless communication system according to any one of 11 to 14. Each of the plurality of multi-carrier CDMA receiving means in the receiving device, a guard interval removing means for removing a guard interval from a received signal, and a serial / parallel converting means for serial / parallel converting an output of the guard interval removing means. A fast Fourier transforming means for fast Fourier transforming the output of the serial / parallel transforming means, a despreading means for multiplying the output of the fast Fourier transforming means by the same spreading code as on the transmitting side to despread, 16. The apparatus according to claim 11, further comprising: a propagation path estimating means for estimating a propagation path; and an equalizing / combining means for equalizing and combining an output of the despreading means from the estimated propagation path. The wireless communication system according to claim 1. Each of the plurality of multi-carrier CDMA receiving units in the receiving device further includes an estimated value combining unit that combines the channel estimation values estimated by the channel estimating unit, and the space-time decoding in the receiving device 17. The wireless communication system according to claim 16, wherein the means is configured to perform the decoding using the combined propagation path estimation value. 18. The wireless communication system according to claim 13, wherein the spread code is a Walsh Hadamard code.

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