JP6872073B2 - Wireless communication method and wireless communication system - Google Patents

Description

Capture by reference

This application claims the priority of Japanese Patent Application No. 2018-27242, which is a Japanese application filed on February 19, 2018, and incorporates it into this application by referring to its contents.

The present invention relates to a wireless communication method for transmitting and receiving data via a wireless propagation path.

As a background technique in this technical field, a technique called BICM-ID (Bit Interleaved Coded Modulation with Iterative decoding) has been proposed. For example, as described in Patent Document 1 and Non-Patent Document 2, in BICM-ID, excellent characteristics can be obtained by repeating a demodulation process for modulation and a decoding process for coding. The characteristics of BICM-ID are determined not by the characteristics of the demodulator and the decoder, but by their matching. Therefore, it is possible to analyze the convergence characteristics by using EXIT (Extrinsic Information Transfer) analysis and design a demodulator and a decoder that realize excellent characteristics (see, for example, Non-Patent Document 3).

Further, in a receiving device of a method using a combination of orthogonal frequency division multiplexing (OFDM) and differential phase shift keying (DPSK) modulation, the soft determination result of the most likely series estimation (MLSE) of the DPSK modulated signal and the decoder are used. A method has been proposed in which the characteristics are improved by performing BICM-ID as compared with the normal delayed detection that does not use BICM-ID.

Japanese Unexamined Patent Publication No. 2010-124367

D. Garg, F. Adachi, "Rate Compatible Punctured Turbo-Coded Hybrid ARQ for OFDM in a Frequency Selective Fading Channel", IEEE VTC 2003 Spring, pp. 2725-2729, April 2003. X. Li and J. A. Ritcey, "Bit-Interleaved Coded Modulation with Iterative Decoding," IEEE Communications Letters, vol. 1, pp. 169171, 1997. S. ten Brink, "Convergence Behavior of Iteratively Decoded Parallel Concatenated Codes," IEEE Transactions on Communications, vol. 49, No. 10, pp. 1727-1737, October 2001.

In a conventional system that transmits DPSK signals in parallel by OFDM, a method that realizes good characteristics by applying a iterative decoding process that uses the MLSE and BICM-ID methods for demodulation processing has been proposed. However, in the iterative decoding method using MLSE and BICM-ID, the symbol length of the DPSK signal for achieving good convergence characteristics in BICM-ID becomes large, so that the symbol length in which good characteristics can be obtained is repeated. Increasing the circuit scale of the decoding processing unit becomes an issue. In particular, the circuit scales of interleavers and deinterleavers that randomly change the order of signals are determined by the size of the data to be processed, which can be a bottleneck for reducing the circuit scale.

A typical example of the invention disclosed in the present application is as follows. That is, it is a wireless communication method for transmitting data from a transmitting device to a receiving device, wherein the transmitting device has a modulator that outputs a DPSK signal in parallel using OFDM, and the receiving device demodulates the wireless signal. An MLSE demodulator that outputs bit information, a decoder that decodes the bit information, an interleave processing unit that changes the bit order of the bit information, a deinterleaver for differential phase shift, and the differential phase bias. It is composed of a demodulator for repetitive decoding whose block length is smaller than that of the transfer demodulator, and has a deinterleave processing unit for exchanging the bit order of the bit information. The differential phase shift demodulator transmits in parallel. It has a function of performing deinterleave processing by exchanging the time order of the DPSK signals, and in the method, the first deinterleaver for differential phase shift and the MLSE demodulator are output from the OFDM demodulator. Deinterleave processing and demodulation processing are performed on the radio signal of the above, the first bit information is output, and the deinterleaver for repeated decoding is based on the order of the bits replaced by the interleaving processing with respect to the first bit information. The demodulation process is performed, the second bit information is output, the decoder decodes the second bit information, the third bit information is output, and the interleave processing unit outputs the third bit information. The third bit information is repeatedly subjected to interleaving processing, which is the reverse of the deinterleaving process, to generate fourth bit information, and the fourth bit information is input to the MLSE demodulator as prior information. Perform decryption processing.

According to a typical embodiment of the present invention, it is possible to suppress an increase in the circuit scale of the iterative decoding process while improving the characteristics of the iterative decoding process. Issues, configurations and effects other than those mentioned above will be clarified by the description of the following examples.

It is a figure which shows the structure of the wireless communication system of the Example of this invention. It is a figure which shows the iterative decoding processing in the retransmission method of the Example of this invention, FIG. 2A is a figure which shows the iterative decoding processing part of the receiving side in this Example, and FIG. 2B is an EXIT analysis result. It is a figure which shows. It is a figure which shows the iterative decoding process of the Example of this invention, and FIG. 3 (A) is a figure which shows the structure which divided the interleaver and deinterliar for the differential phase shift and the iterative decoding process, and is FIG. B) is a diagram showing a configuration in which a deinterleaver for differential phase shift keying is repeatedly provided outside the decoding processing unit. It is a figure which shows the iterative decoding process using OFDM and DPSK of the Example of this invention. It is a figure which shows the iterative decoding process using OFDM and DPSK of the Example of this invention. It is a figure which shows an example of the deinterleave processing for DPSK. It is a figure which shows an example of the deinterleave processing for DPSK of the Example of this invention. It is a figure which shows an example of the deinterleaved processing for repetitive decoding processing. It is a figure which shows an example of the deinterleaved processing for the iterative decoding process of the Example of this invention. It is a figure which shows the structure of the deinterer for repeated decoding of the Example of this invention. It is a figure which shows an example of the deinterleaved processing for the iterative decoding process of the Example of this invention. It is a figure which shows the error rate characteristic in the wireless communication system of the Example of this invention.

<Example 1>
Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a wireless communication system according to an embodiment of the present invention.

The wireless communication system of this embodiment includes a encoder 10, an interleaver 11, a DPSK (differential phase shift) modulator 12, a transmitter having an OFDM (Orthogonal Frequency Division Multiplexing) modulator 13 and an antenna 14, and an OFDM demodulator. 17. It is composed of a receiver having a repetitive decoding processing unit 21 and an antenna 16. The transmitter and the receiver are connected via a radio propagation path 15.

In the transmitter, the encoder 10 encodes the information bits, the interleaver 11 replaces the bit order in the code words output from the encoder 10, the DPSK modulator 12 performs differential shift modulation, and the OFDM modulator 13 Puts a plurality of DPSK signals on the subcarrier and outputs them from the antenna 14.

The repetitive decoding processing unit 21 of the receiver includes a DPSK demodulator 18, a deinterleaver 19, a decoder 20, and an interleaver 24. In the receiver, a signal is received via the radio propagation path 15, the OFDM demodulator 17 demodulates the received signal, the DPSK demodulator 18 demodulates the demodulated result, and the deinterleaver 19 performs reverse processing of the interleaver 11. The bit order is restored and the decoder 20 decodes. The decoding result is input to the DPSK demodulator 18 via the interleaver 24, and the DPSK demodulator 18 refers to the decoding result of the decoder 20 and outputs a more accurate demodulation result (BICM-ID processing).

FIG. 2A is a diagram showing the repeat decoding processing unit 21 of the receiver in this embodiment, and FIG. 2B is a diagram showing the EXIT analysis result of the iterative decoding processing. Blind (no channel information) demodulation using maximum likelihood sequence estimation (MLSE) is used for the soft determination decoding process of DPSK.

As the likelihood information exchanged between the demodulator and the decoder by BICM-ID, a bitwise log-likelihood ratio (LLR) is generally used. LLR is a logarithmic expression of the ratio of the probability that the bit b is 0 to the probability that the bit b is 1, and is represented by the mathematical formula (1).

In formula (1), P (b = 0) indicates the probability that b is 0, and P (b = 1) indicates the probability that b is 1.

The convergence characteristics of the repeated decoding process of BICM-ID can be analyzed by the EXIT (Extrinsic Information Transfer) analysis described in Non-Patent Document 3. In the EXIT analysis, the input / output characteristics of the decoder and demodulator are displayed in the form of the mutual information amount Im of the bits represented by the mathematical formula (2), and the characteristics of both are superimposed and plotted on one chart for repeated decoding. The amount of information obtained by processing can be analyzed.

The mutual information amount of the formula (2) is the average of all the codewords of the mutual information amount of bits, and is represented by a value of 0 to 1, and the closer it is to 1, the larger the bit likelihood of the entire codeword.

If the demodulator's prior information IA _{, DEM} and the decoder's external information _{IE, DEC} are on the horizontal axis, and the demodulator's external information IA _{, DEM} , the decoder's prior information _{IE, DEC} are on the vertical axis, The amount of mutual information increases according to each characteristic by the iterative decoding process. When both characteristics intersect, the increase in mutual information stops at the intersection, and an error remains in the decoding result. In FIG. 2B, since the convergence characteristics of the demodulator and the decoder do not intersect in the analysis result 23, it is possible to obtain an error-free result. However, since the convergence characteristic is determined by the average of all the codewords, a codeword that is sufficiently asymptotic to the average value is required. In DPSK modulation using OFDM, DPSK modulation is used in the time direction to follow the time fluctuation of the channel. In this case, the DPSK modulation data of each subcarrier is one per OFDM symbol, which is a good convergence. In general, 1000 OFDM symbols or more are required to obtain DPSK-modulated data for obtaining characteristics. In this case, the scale of data processed by the iterative decoding processing unit becomes large, and in particular, the scale of interleavers and deinterleavers can become a bottleneck in reducing the circuit scale.

In the present invention, in order to solve the problem of circuit scale, DPSK signals of a small number of OFDM symbols are bundled in the subcarrier direction by associating the DPSK signals transmitted in parallel via the interleaver 24, the decoder 20, and the deinterleaver 19. Provided is a signal processing method for constructing a code word capable of obtaining good convergence characteristics, and a method for dividing the interleaver 24 and the deinterleaver 19 into a plurality of parts and reducing the interleaver 24 and the deinterleaver 19 included in the repeat decoding unit.

FIG. 3 is a diagram showing the iterative decoding processing unit 21 of the embodiment of the present invention, and FIG. 3 (A) divides the deinterleaver into a differential phase shift deinterleaver 31 and a deinterleaver 32 for repetitive decoding. The figure shows a configuration in which the interleaver is divided into a differential phase shift 33 and a repetitive decoding process 32. FIG. 3 (B) shows a differential phase shift deinterleaver 31 with a repetitive decoding processing unit 21. It is a figure which shows the structure provided outside of.

In the embodiment of the present invention, since the DPSK signals of a plurality of subcarriers are bundled and treated as one code word, the minimum OFDM symbol length required to obtain good characteristics in BICM-ID can be shortened. However, since the original size of the interleaver is selected so as to be large enough to obtain diversity for channel fluctuations, it is not determined only by the codeword size required for the convergence characteristics of BICM-ID. Therefore, it is divided into a differential phase shift deinterleaver 31 whose magnitude is selected with respect to the channel variation and a deinterleaver 32 required by the iterative decoding processing unit 21, and the differential phase shift deinterleave processing is repeatedly decoded. The configuration is to be performed before. In FIG. 3A, the differential phase shift deinterleaver 31 has a block size larger than that of the deinterleaver 32 for repetitive decoding, and is designed so that sufficient diversity can be obtained with respect to channel fluctuations.

Here, the MLSE demodulator 22 executes a process of estimating the transmission bit from the phase difference of the adjacent signals, and if the front-back relationship of the DPSK signal is maintained in the differential phase shift deinterleaver 31, the MLSE and the MLSE demodulator 22 The order of is changed, and it can be repeatedly taken out of the decoding processing unit 21. That is, as shown in FIG. 3B, the differential phase shift deinterleaver 31 is provided in front of the MLSE demodulator 22 and executes processing outside the iterative decoding processing unit 21, so that it is differential. Deinterleaved processing for phase shift is not required. With such a configuration, the circuit scale of the repetitive decoding processing unit 21 can be reduced. The deinterleaved process is a reverse process of the interleaved process, and the interleaved process and the deinterleaved process of the embodiment of the present invention will be described below mainly using the deinterleaved process on the receiving side.

FIG. 4 is a diagram showing repeated decoding processing using OFDM and DPSK. The DPSK signal 41 is arranged in the OFDM time direction, and the DSPK signals in the frequency direction are independent of each other. In MLSE, adjacent DPSK signals are required for processing the DPSK symbol 42. Therefore, when the order of the DPSK signals in the time direction is changed by interleaving, interleaving and deinterleaving are performed between the MLSE 22 and the decoder 20. Is required. The iterative decoding processing unit 21 repeatedly decodes the DPSK signal having a sufficient length and the decoding result of the decoder 20 for each subcarrier.

FIG. 5 is a diagram showing a repeated decoding process using OFDM and DPSK according to an embodiment of the present invention. The DPSK signal is shorter than the symbol length of the differential phase shift deinterleaver 31, and the DPSK signals of a plurality of subcarriers are processed as one MLSE group. As for the decoding result, the one that is summarized in the time and subcarrier directions is used as one code word, and the decoding is repeated.

Next, the differential phase shift interleaving process and the deinterleaving process according to the embodiment of the present invention will be described with reference to FIGS. 6 and 7.

FIG. 6 is a diagram showing an example of the conventional deinterleave processing for differential phase shift, and shows the time of the DPSK symbol 42 in the DPSK signal 41 of the subcarrier before and after the deinterleave processing in which the time order of the 100 OFDM symbols is randomly changed. Shows the order. In FIG. 6, in the deinterleave result 61, since the time order of the DPSK symbol 42 is changed in the subcarrier before the deinterleave, it is necessary to restore the order changed before the MLSE, and the deinterleaver for differential phase shift is used. It becomes difficult to repeatedly put 31 out of decoding.

FIG. 7 is a diagram showing an example of a deinterleaved process for differential phase shift according to an embodiment of the present invention. In FIG. 7, the deinterleave result 71 realizes the deinterleave function by changing the time order between the subcarriers while maintaining the time order of the DPSK symbols 42 in the DPSK signal 41 of the subcarriers. A delay of 1 to 100 symbols is randomly inserted into the DPSK symbol 42 after deinterleaving for each subcarrier, and if the number of subcarriers is sufficiently large, a diversity effect for 100 symbols can be expected. In this case, in the DPSK signal 41, the time order of the DPSK symbols 42 is maintained before and after the deinterleave, and the relationship between the adjacent DPSK symbols 42 required by the MLSE is maintained. It can be easily replaced.

Next, the iterative decoding interleaving and deinterleaving processing of the embodiment of the present invention will be described with reference to FIGS. 8 to 11.

FIG. 8 is a diagram showing an example of deinterleave processing using a conventional interleaver as a deinterleaver for repetitive decoding processing. In the deinterleave for iterative processing, the signal deinterleaved in the time direction in the deinterleave for differential phase shift is deinterleaved. It is desirable that the deinterleave processing of the iterative decoding unit be as small as possible, but when the deinterleave processing in the frequency direction of the OFDM symbol unit is simply combined, the likelihood of the DPSK signal 41 of each subcarrier in the iterative decoding processing is Information is not exchanged and good convergence characteristics cannot be achieved. Whether or not the DPSK signal 41 is associated in the iterative decoding process can be confirmed by the index in the subcarrier direction of 81 after deinterleaving. In the deinterleaved result 81 shown in FIG. 8, the index in the subcarrier direction of the DPSK signal 41 only includes f75, and the association between the DPSK signals 41 is limited.

FIG. 9 is a diagram showing an example of a deinterleaved process for repeated decoding processing according to an embodiment of the present invention. The deinterleaver shown in FIG. 9 randomly swaps both the time and frequency directions within the MLSE group of the demodulator. In the DPSK signal 41 of the deinterleave result 91 shown in FIG. 9, the index in the frequency direction includes f75, f99, f72, and f42, and the likelihood information is exchanged between the DPSK signals of these subcarriers. In this case, interleaving processing and deinterleaving processing are required before and after MLSE, but since the symbol length is shorter than that of the deinterleaver for differential phase shift, the circuit scale can be reduced.

Good characteristics can be obtained by using the block interleaver of FIG. 9, but the function required as the iterative decoding interleaver of the embodiment of the present invention is that the interleaving process is different from one OFDM symbol unit. That is, as shown in FIG. 8, if the unit of interleaving processing is equal to one OFDM symbol unit, interleaving processing is performed in units of OFDM symbols, but as shown in FIG. 9, the unit of interleaving processing is one OFDM symbol. If it is different from the unit, the deviation width changes for each interleaving process, and the OFDM symbol unit and the interleaving process deviate from each other. That is, after the interleaving processing and the deinterleaving processing of all the DPSK signals in the MLSE group are completed, the DPSK signal 41 of one subcarrier contains the likelihood information of a plurality of subcarriers. Therefore, better characteristics can be realized. The unit of interleaving processing is preferably larger than one OFDM symbol unit, but may be smaller.

Further, even if the interleaving process is the same as one OFDM symbol unit, good characteristics can be realized by combining a convolution bit interleaving or a plurality of interleaving.

FIG. 10 shows the configuration of the deinterleaver 32 for repetitive decoding when the interleaving process is the same as one OFDM and is combined with the convolution bit interleaver. The block deinterleaver 102 is, for example, a deinterleaver in which the positions of subcarriers in one OFDM symbol are randomly exchanged by interleaving (bits on the subcarriers in subcarrier units) and returned to the original order. The output of the deinterleaver is delayed by the bitwise convolution deinterleaver 101, and the delay added by the interleaver is returned to the original order. In this case, although the deinterleave processing by the block deinterleaver 102 is closed in one OFDM symbol, some bits in one OFDM symbol are mixed with bits in another OFDM symbol in the subsequent convolution deinterleaver. , Good characteristics can be realized by the iterative decoding of the present invention.

In the iterative decoding deinterleaver 32 shown in FIG. 10, the bit order can be exchanged with different exchange patterns when viewed in bit units. That is, the interleaving pattern can be switched for each OFDM symbol, the likelihood information is exchanged between the DPSK signals of the subcarriers, and good characteristics can be realized.

FIG. 11 is a diagram showing an example in which a plurality of OFDM symbol unit deinterleavers are combined. In FIG. 11, the deinterleaver randomly replaces the subcarriers in one OFDM symbol. However, a different interleaving pattern is used for each OFDM symbol, and the DPSK signal 41 of the deinterleaving result 111 includes frequency indexes f75, f99, f72, and f42, and the likelihood information between the DPSK signals of these subcarriers. Is exchanged. In the example shown in FIG. 11, good characteristics can be realized without combining with the convolution deinterleaver 101 as shown in FIG.

FIG. 12 is a diagram showing an error rate characteristic in the wireless communication system according to the embodiment of the present invention. The characteristic of delayed detection when BICM-ID is not used is represented by □, the characteristic when BICM-ID is used is represented by ◯, and the characteristic using the iterative decoding unit of the embodiment of the present invention is represented by ×. From FIG. 12, by using the method of the present invention, it is possible to improve the SNR from BICM-ID while reducing the circuit scale.

As described above, according to the embodiment of the present invention, in the wireless communication system for transmitting data from the transmitting device to the receiving device, the differential phase shift deinteraver 31 and the MLSE demodulator 22 cooperate with each other. Then, the first radio signal output from the OFDM demodulator 17 is deinterleaved and demodulated, the first bit information is output, and the deinterleaver 32 for repetitive decoding receives the first bit information. The deinterleave processing that restores the order of the bits replaced by the interleave processing is performed, the second bit information is output, and the decoder 20 decodes the second bit information and outputs the third bit information. Then, the interleaving processing unit 34 performs interleaving processing, which is the reverse of the deinterleaving processing, on the third bit information to generate the fourth bit information, and sends the second bit information to the MLSE demodulator as prior information. Since the iterative decoding process is performed by inputting the data, it is possible to suppress an increase in the circuit scale of the iterative decoding process while improving the characteristics of the iterative decoding process (reducing the required SNR in the error rate characteristic).

Further, the differential phase shift deinterleaver 31 is arranged in front of the MLSE demodulator 22, and the differential phase shift deinterleaver 31 is a second radio in which the first radio signal is deinterleaved. The signal is output, the MLSE demodulator 22 demodulates the second radio signal using the prior information, and outputs the first bit information. Therefore, the differential phase shift deinterleaver 31 is repeatedly decoded by the decoding processing unit 21. It can be arranged outside the above, eliminating the need for deinterleaved processing for differential phase shift keying, and reducing the circuit scale of the iterative decoding processing unit 21.

Further, the deinteraver 32 for repetitive decoding has a function of exchanging the bit order across at least two or more OFDM signals, and the MLSE demodulator 22 has a DPSK whose block size is smaller than that of the deinterleaver 31 for differential phase shift. Since the demodulated signal is demodulated and the demodulated result of the DPSK signal whose bit order is exchanged by the deinterleaver 32 for repeated decoding is repeatedly decoded between the decoders 20, the OFDM symbol unit and the interleave processing are deviated from each other. The likelihood information is exchanged between the carrier's DPSK signals, and better characteristics can be realized.

Further, since the repeatedly decoding deinterleaver 32 has a function of exchanging the bit order across at least two or more OFDM signals, the size of the bit information to be exchanged is different from that of one OFDM symbol, so that the deinterleaver 32 is interleaved with the OFDM symbol unit. Therefore, the likelihood information is exchanged between the DPSK signals of the subcarriers, and better characteristics can be realized.

Further, since the repeatedly decoding deinterleaver 32 has the same size of the bit information to be exchanged as one OFDM symbol and has a function of exchanging the bit order with different exchange patterns across at least two or more OFDM signals, it is possible to perform an OFDM. Since the symbol unit and the interleaving process deviate from each other, the likelihood information is exchanged between the DPSK signals of the subcarriers, and better characteristics can be realized.

Further, since the deinterleaver 32 for repetitive decoding is composed of a deinterleaver having the same magnitude of bit information to be exchanged as one OFDM symbol and an interleaver having a different delay time within one OFDM symbol, each OFDM symbol is configured. The interleaving pattern can be switched, the likelihood information is exchanged between the DPSK signals of the subcarriers, and good characteristics can be realized.

The present invention is not limited to the above-described embodiment, and includes various modifications and equivalent configurations within the scope of the attached claims. For example, the above-described examples have been described in detail in order to explain the present invention in an easy-to-understand manner, and the present invention is not necessarily limited to those having all the described configurations. Further, a part of the configuration of one embodiment may be replaced with the configuration of another embodiment. Further, the configuration of another embodiment may be added to the configuration of one embodiment. In addition, other configurations may be added / deleted / replaced with respect to a part of the configurations of each embodiment.

Further, each of the above-described configurations, functions, processing units, processing means, etc. may be realized by hardware by designing a part or all of them by, for example, an integrated circuit, and the processor realizes each function. It may be realized by software by interpreting and executing the program to be executed.

Information such as programs, tables, and files that realize each function can be stored in a memory, a hard disk, a storage device such as an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.

In addition, the control lines and information lines indicate those that are considered necessary for explanation, and do not necessarily indicate all the control lines and information lines necessary for implementation. In practice, it can be considered that almost all configurations are interconnected.

Claims (12)

A wireless communication method for transmitting data from a transmitting device to a receiving device.
The transmitter has a modulator that outputs DPSK signals in parallel using OFDM.
The receiving device is
An MLSE demodulator that demodulates wireless signals and outputs bit information,
A decoder that decodes the bit information and
An interleave processing unit that performs interleaving processing that replaces the bit order of the bit information,
A deinterleaved process that is composed of a deinterleaver for differential phase shift keying and a deinterleaver for repetitive decoding whose block length is smaller than that of the deinterleaver for differential phase shift keying, and performs deinterleaved processing for exchanging the bit order of the bit information. Has a part and
The method is
The differential phase shift deinterleaver and the MLSE demodulator perform deinterleave processing and demodulation processing on the first radio signal output from the OFDM demodulator, and output the first bit information.
The iterative decoding deinterleaver performs deinterleave processing on the first bit information to restore the order of the bits replaced in the interleave process, and outputs the second bit information.
The decoder decodes the second bit information and outputs the third bit information.
The interleaving processing unit performs interleaving processing on the third bit information, which is the reverse of the deinterleaving processing, to generate fourth bit information, and the MLSE demodulation using the fourth bit information as prior information. Input to the vessel,
A wireless communication method characterized by repeatedly performing decoding processing by the above processing. The wireless communication method according to claim 1.
The differential phase shift deinterleaver is arranged in front of the MLSE demodulator.
The method is
The differential phase shift deinterleaver outputs a second radio signal obtained by deinterleaving the first radio signal.
A wireless communication method, wherein the MLSE demodulator demodulates a second radio signal using the prior information and outputs first bit information. The wireless communication method according to claim 1.
The repetitive decoding deinterleaver is a wireless communication method characterized in that the bit order is exchanged across at least two or more OFDM signals. The wireless communication method according to claim 1.
The repetitive decoding deinterleaver is a wireless communication method characterized in that the size of the bit information to be exchanged is different from that of one OFDM symbol, and the bit order is exchanged across at least two or more OFDM signals. The wireless communication method according to claim 1.
The repetitive decoding deinterleaver is a wireless communication method characterized in that the size of the bit information to be exchanged is the same as that of one OFDM symbol, and the bit order is exchanged in different exchange patterns across at least two or more OFDM signals. .. The wireless communication method according to claim 5.
The repetitive decoding deinterleaver is a wireless communication method comprising a deinterleaver having the same magnitude of bit information to be exchanged as one OFDM symbol and an interleaver having different delay times within one OFDM symbol. .. A wireless communication system that transmits data from a transmitting device to a receiving device.
The transmitter has a modulator that outputs DPSK signals in parallel using OFDM.
The receiving device is
An MLSE demodulator that demodulates wireless signals and outputs bit information,
A decoder that decodes the bit information and
An interleave processing unit that performs interleaving processing that replaces the bit order of the bit information,
A deinterleaved process that is composed of a deinterleaver for differential phase shift keying and a deinterleaver for repetitive decoding whose block length is smaller than that of the deinterleaver for differential phase shift keying, and performs deinterleaved processing for exchanging the bit order of the bit information. Has a part and
The differential phase shift deinterleaver and the MLSE demodulator perform deinterleave processing and demodulation processing on the first radio signal output from the OFDM demodulator, output the first bit information, and output the first bit information.
The iterative decoding deinterleaver performs deinterleave processing on the first bit information to restore the order of the bits replaced in the interleave process, and outputs the second bit information.
The decoder decodes the second bit information and outputs the third bit information.
The interleaving processing unit performs interleaving processing, which is the reverse of the deinterleaving processing, on the third bit information to generate fourth bit information, and the MLSE demodulation using the fourth bit information as prior information. Input to the vessel,
A wireless communication system characterized by repeatedly performing decoding processing by the above processing. The wireless communication system according to claim 7.
The differential phase shift deinterleaver is arranged in front of the MLSE demodulator.
The differential phase shift deinterleaver outputs a second radio signal obtained by deinterleaving the first radio signal.
The MLSE demodulator is a wireless communication system characterized in that the second radio signal is demodulated using the prior information and the first bit information is output. The wireless communication system according to claim 7.
The repetitive decoding deinterleaver is a wireless communication system having a function of exchanging bit orders across at least two or more OFDM signals. The wireless communication system according to claim 7.
The iterative decoding deinterleaver is a wireless communication system having a function of exchanging bit orders across at least two or more OFDM signals, in which the size of the bit information to be exchanged is different from that of one OFDM symbol. The wireless communication system according to claim 7.
The iterative decoding deinterleaver is characterized in that the size of the bit information to be exchanged is the same as that of one OFDM symbol, and the bit order is exchanged in different exchange patterns across at least two or more OFDM signals. Wireless communication system. The wireless communication system according to claim 11.
The repetitive decoding deinterleaver is a wireless communication system characterized in that the deinterleaver having the same magnitude of bit information to be exchanged is composed of a deinterleaver having the same magnitude as one OFDM symbol and an interleaver having different delay times within one OFDM symbol. ..

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