JP2007081931A - Wireless transmission apparatus and wireless reception apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless transmission apparatus capable of executing proper repetitive decoding processing by decreasing the delay time of Viterbi decoding processing. <P>SOLUTION: The wireless transmission apparatus includes a decoding completion bit addition section, which attaches a known bit sequence as decoding completion bits for decode processing to the tail end of a symbol that is an interleaving processing unit (S14, S16). Furthermore, the wireless transmission apparatus includes a convolution coding section for applying convolution coding to the symbols, having the decoding completion bits attached thereto by the decoding completion bit addition section; an interleave section for interleaving the symbols coded by the convolution coding section; and a data transmission section for transmitting data interleaved by the interleave section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wireless transmission device and a wireless reception device that perform wireless transmission of a signal using a convolutional code.

  In wireless transmission communication, various technologies are used as countermeasures against degradation of reception quality caused by transmission path fluctuations and interference of interference signals.

  For example, an error encoding / correction technique is used in which error correction encoding is performed on transmission data on the transmission side and error correction decoding is performed on the reception side. In the wireless LAN standard IEEE802.11a, a convolutional code is adopted as an error correction code, and Viterbi decoding is adopted as an error decoder.

  In addition, as a countermeasure against burst errors in which reception quality deteriorates continuously for a certain period of time, interleaving is performed by distributing the data in time by the transmission side changing the order of transmission data according to a predetermined rule, and returning the data in the original data order There is processing. The interleaving process prevents a fatal trouble that the entire data of the part is lost due to a data error caused by noise or the like that persists across blocks.

  In addition, an interference cancellation technique for removing interference signals other than the desired signal is also important. For example, in a CDMA communication system, a transmission signal replica of another user is generated using a spreading code of another user, and a process of removing the other user's signal from the received signal is performed.

  IEEE 802.11n, which is a high-speed wireless LAN standard, employs a MIMO (Multi-Input Multi-Output) transmission technology that simultaneously transmits and receives a plurality of transmission streams using a plurality of transmission and reception antennas. As one of the techniques for improving the quality, there is a background that it is possible to apply iterative decoding that repeats decoding processing of a received signal. In the iterative decoding process, the reception quality can be improved by selecting an appropriate number of iterations.

In order to sufficiently obtain the above-described interleaving effect, it is necessary to select an interleaving size that is in accordance with the propagation speed of the propagation path. However, iterative decoding processing and a large interleave size greatly affect processing delay. In interleaving and deinterleaving processing, data replacement processing cannot be performed until data for the interleaving size has been prepared. Therefore, in iterative decoding in which interleaving and deinterleaving processing are repeated a plurality of times, measures for reducing processing delay are important. For example, in Non-Patent Document 1, iterative decoding is performed by setting the interleave size to the OFDM symbol size for the purpose of reducing the processing delay.
"Characteristics of error correction coding MIMO-OFDM using parallel interference canceller", Shibahara, Nishimura, Ogane, Ogawa, IEICE RCS2004-81, IEICE

  On the receiving side, it is known that in order to obtain sufficient reception performance, it is necessary to ensure a traceback length of 5 times or more the constraint length in the Viterbi decoding process. Therefore, Viterbi decoding is completed for the first time only when the branch metric corresponding to the traceback length is input after the last branch metric is input to the Viterbi decoder. That is, after the branch metric at the end of the original transmission data is input, the branch metric based on the tail bit given on the transmission side is input, so that the Viterbi decoding process for the original transmission data can be completed.

  A radio transmission apparatus that performs convolutional coding, Viterbi decoding processing, and interleaving / deinterleaving processing must wait for the arrival of the next interleave because a branch metric is input after the end of the original transmission data. There was a problem of processing delay during decoding. In particular, a wireless transmission apparatus that performs iterative decoding processing has a problem that the number of iterative decoding is limited, and iterative decoding does not end within a prescribed time depending on the interleave size.

  In view of the above background, an object of the present invention is to provide a wireless transmission device and a wireless reception device capable of reducing the delay time of Viterbi decoding processing and performing appropriate iterative decoding processing.

  The wireless transmission device of the present invention includes a decoding completion bit adding unit that adds a known bit string as a decoding completion bit for enabling decoding processing to the end of a symbol that is an interleaving processing unit, and the decoding completion bit addition. A convolutional encoding unit that convolutionally encodes the symbol to which the decoding completion bit is added by the unit, an interleaving unit that interleaves the symbols encoded by the convolutional encoding unit, and data interleaved by the interleaving unit A data transmission unit for transmission.

  With this configuration, since a known bit sequence that enables decoding processing is added to the end of each symbol as a decoding completion bit, the radio reception apparatus that has received the convolutional signal decodes the symbol based on the known bit sequence. Can be done. That is, since the symbol can be decoded without waiting for the arrival of the next symbol on the receiving side, the delay of the decoding process can be reduced. The “known bit string” is a bit string known to the receiving side that performs Viterbi decoding at the time of decoding. It may be a predetermined bit string, or may be a bit string that has been decoded prior to the start of decoding of a symbol to be decoded and is known to the receiving side at the time of decoding.

  In the wireless transmission device of the present invention, the decoding completion bit adding unit may add a predetermined length bit consisting of all 0s as the decoding completion bit to the end of the symbol.

  With this configuration, Viterbi decoding can be performed using so-called tail bits.

  In the wireless transmission device of the present invention, the decoding completion bit adding unit may duplicate bit data of a predetermined length in the same symbol and add the duplicated bit data to the end of the symbol.

  With this configuration, it is possible to perform Viterbi decoding using a branch metric in the wireless reception device.

  The radio reception apparatus of the present invention receives data that is convolutionally encoded by adding a known bit string as a decoding completion bit for enabling decoding processing to the end of a symbol that is an interleaving processing unit. And a deinterleaving unit for deinterleaving the data received by the data receiving unit for each symbol, and the data deinterleaved by the deinterleaving unit based on the decoding completion bit for each symbol A Viterbi decoding unit.

  With this configuration, symbols can be decoded based on a known bit string. That is, since the symbol can be decoded without waiting for the arrival of the next symbol, the delay of the decoding process can be reduced.

  The radio reception apparatus of the present invention includes a convolutional encoding unit that performs convolutional encoding on the symbols that are Viterbi decoded by the Viterbi decoding unit, an interleaving unit that interleaves the symbols encoded by the convolutional encoding unit, A replica signal generation unit that generates a replica signal of the symbol based on a symbol interleaved by the interleaving unit, and interference of a signal received by the data reception unit by the replica signal generated by the replica signal generation unit And an interference canceling unit for canceling.

  As described above, in the configuration having the interference canceling unit, it is necessary to decode the decoded data again to generate a replica signal, so that there is a particularly large demand for promptly decoding the data. With the configuration of the present invention, Viterbi decoding can be performed promptly without waiting for the arrival of the next symbol, so that the radio reception apparatus can appropriately cancel interference.

  In the radio reception apparatus of the present invention, the data reception unit may receive convolutionally encoded data in which a predetermined length bit consisting of all 0s is added to the end of the symbol as the decoding completion bit.

  With this configuration, Viterbi decoding can be performed using so-called tail bits.

  In the radio reception apparatus of the present invention, the data reception unit replicates bit data having a predetermined length in the same symbol, and receives the convolutionally encoded data in which the duplicated bit data is added to the end of the symbol. May be.

  With this configuration, Viterbi decoding can be performed using a branch metric.

  According to the present invention, since a known bit string is added to the end of each symbol as a decoding completion bit that enables decoding processing, the radio reception device that has received the convolutional signal promptly uses the known bit string. Symbol decoding can be performed, and a delay in decoding processing can be reduced.

Hereinafter, a wireless transmission device and a wireless reception device according to an embodiment of the present invention will be described with reference to the drawings.
(First embodiment)
In this embodiment, an example in which a MIMO transmitter is used as a wireless transmission device and a MIMO receiver is used as a wireless reception device will be described. Both the MIMO transmitter and the MIMO receiver are provided with two antennas and transmit two streams between the MIMO transmitter and the MIMO receiver.

  FIG. 1 is a diagram illustrating a transmission frame generation procedure by the MIMO transmitter according to the first embodiment. The configuration of the MIMO transmitter and the MIMO receiver will be described with reference to FIG. 1 before describing the transmission frame generation procedure by the MIMO transmitter of the present embodiment.

  2 to 4 are diagrams illustrating the configuration of the MIMO transmitter 10 according to the first embodiment, and FIG. 5 is a diagram illustrating the configuration of the MIMO receiver 30.

  As shown in FIG. 2, the MIMO transmitter 10 includes a transmission frame generation unit 11, a convolutional coding unit 12, an interleaving unit 13, a mapping unit 14, an OFDM modulation unit 15, and an RF unit 16. Yes.

  The MIMO transmitter 10 convolutionally encodes the transmission frame generated by the transmission frame generation unit 11 by the convolutional encoding unit 12 and interleaves the encoded transmission frame by the interleaving unit 13. The MIMO transmitter 10 maps the interleaved data according to the modulation scheme applied by the mapping unit 14 and performs OFDM modulation by the OFDM modulation unit 15 to generate an OFDM symbol. The MIMO transmitter 10 up-converts the generated OFDM symbol by the RF unit 16 and transmits it from the transmission antenna.

  The transmission frame generation unit 11 has a function of generating a transmission frame. FIG. 3 is a diagram illustrating a configuration of the transmission frame generation unit 11. The transmission frame generation unit 11 includes a transmission bit generation unit 21, a tail bit / padding bit insertion control unit 22, and a FIFO unit 23. The transmission bit generation unit 21 generates transmission bits based on the information of the transmission frame, and stores the generated transmission bits in the FIFO unit 23. The tail bit / padding bit insertion control unit 22 controls the insertion of tail bits and padding bits into transmission bits. The tail bit insertion control by the tail bit and padding bit insertion control unit 22 of the present embodiment will be described in detail later with reference to FIG.

  Returning to FIG. 2, the convolutional encoding unit 12 has a function of performing convolutional encoding on the transmission frame generated by the transmission frame generating unit 11. FIG. 3 is a diagram illustrating a configuration of the convolutional encoding unit 12. The convolutional encoding unit 12 holds the input data in a (restraint length-1) stage shift register, and obtains certain data input to the convolutional encoding unit 12 using the values of the past six data. 2 bits are output as the result of convolutional encoding of data. After the final data of the frame is input to the convolutional code unit 12, the Tail bit (6 bits, all zeros) is input, and the values of all the shift registers of the convolutional code unit 12 are set to zero, thereby performing the convolutional encoding process. Terminate. As the convolutional encoding unit 12, a convolutional encoder conforming to the IEEE 802.11a wireless LAN standard can be used.

  Next, the MIMO receiver 30 will be described with reference to FIG. The MIMO receiver 30 includes an RF unit 31, an OFDM demodulation unit 32, a channel estimation / separation unit 33, a branch metric calculation unit 34, a deinterleaving unit 35, a Viterbi decoding unit 36, and an iterative decoding unit 40. . The iterative decoding unit 40 includes a replica generation unit 41, an interference cancellation unit 42, a branch metric calculation unit 43, a deinterleaving unit 44, a Viterbi decoding unit 45, a convolutional encoding unit 46, an interleaving unit 47, a mapping Part 48.

  The MIMO receiver 30 down-converts the reception signal received by the reception antenna by the RF unit 31 and then performs OFDM demodulation by the OFDM demodulation unit 32. The channel estimation / separation unit 33 of the MIMO receiver 30 estimates channel characteristics between the transmission and reception antennas using a known signal transmitted from the transmission side. Further, the channel estimation / separation unit 33 separates the data of each stream from the OFDM demodulated symbol data received by interfering with the data of two streams by channel separation processing such as ZF (Zero Forcing), for example. The branch metric calculation unit 34 obtains a branch metric using the data after channel separation, deinterleaves it with the deinterleaving unit 35, and then decodes the deinterleaved data with the Viterbi decoding unit 36.

  The iterative decoding unit 40 performs convolutional coding, interleaving, and mapping similar to those on the transmission side on the Viterbi decoding result, and the replica generation unit 41 multiplies the channel estimation result, thereby receiving signals between the transmitting and receiving antennas. The replica signal is generated. The interference cancellation unit 42 subtracts the replica signal generated by the replica generation unit 41 from the OFDM demodulated signal, thereby obtaining a signal of each stream. For each of the stream signals, branch metric calculation, deinterleaving, and Viterbi decoding are performed as in the first stage processing of the receiver. After repeating this iterative decoding process, received data is obtained.

  Next, a transmission frame generation procedure by the MIMO transmitter 10 of the first embodiment will be described with reference to FIG. The transmission frame generation unit 11 generates transmission bits by the transmission bit generation unit 21 (S10), and accumulates the generated transmission bits in the FIFO unit 23 (S12). Next, the transmission frame generation unit 11 determines whether or not the number of bits accumulated in the FIFO unit 23 since the previous insertion of the Tail bit has reached (interleave size−Tail bit number) (S14). If it is determined that the number of accumulated bits has reached (interleave size-number of tail bits) (YES in S14), tail bits and padding bit insertion control unit 22 inserts tail bits (S16). If the number of accumulated bits has not reached (interleave size-number of tail bits) (NO in S14), the process proceeds to the next step without inserting tail bits.

  The transmission frame generation unit 11 determines whether or not to end the bit generation (S18). If it is determined not to end the bit generation (NO in S18), the transmission bits are stored again in the FIFO unit 23 (S12). The above-described processing is repeated until it is determined that the bit generation is finished.

  In the determination of whether or not to end the bit generation (S18), when it is determined that the bit generation is to be ended (YES in S18), the transmission frame generation unit 11 determines the number of FIFO stored bits including the accumulated tail bits. Is (multiple of interleave size-number of tail bits) or not (S20). As a result of this determination, if it is determined that the accumulated bit number is (multiple of interleave size−Tail bit number) (YES in S20), the Tail bit / padding bit insertion control unit 22 inserts the Tail bit ( S24). As a result of this determination, if it is determined that the accumulated bit number is not (multiple of the interleave size−Tail bit number) (NO in S20), the Tail bit / padding bit insertion control unit 22 is accumulated in the FIFO unit. Padding bits are inserted so that the number of bits becomes (multiple of interleave size-number of tail bits) (S22), and then tail bits are inserted (S24).

  The effects of the MIMO transmitter 10 and the MIMO receiver 30 of the present embodiment configured as described above will be described.

  The MIMO transmitter 10 of the present embodiment inserts a Tail bit at the end of each symbol, that is, at the end of each symbol, as shown in the transmission frame generation procedure of FIG. Thereby, the processing delay of Viterbi decoding can be reduced. This point will be described with reference to FIGS. FIG. 6 is a diagram illustrating an example of conventional convolutional coding and Viterbi decoding, and FIG. 7 is a diagram illustrating convolutional coding and Viterbi decoding according to the present embodiment. 6 and 7 are conceptual diagrams for explaining the state of data at each stage from transmission frame encoding and transmission to decoding. In both figures, only the part necessary for explaining the processing time is shown.

In order to help understand the effects of the present embodiment, first, conventional convolutional coding and Viterbi decoding will be described with reference to FIG.
On the transmission side, after the tail bit TB is added to the end of the transmission frame composed of a plurality of symbols SB1, SB2,... SBn, the transmission frame is convolutionally encoded. The convolutionally encoded transmission frame is interleaved in units of interleave size.

  On the receiving side, the branch metric obtained from the branch metric calculation unit 34 is input to the deinterleaving unit 35, deinterleaved by the deinterleaving unit 35, and output. In FIG. 6, the deinterleave output processing time is shorter than the deinterleave input because all the data for the interleave size is available at the start of the deinterleave process, so the deinterleave result can be output at high speed. This is because it can.

  The deinterleaved output is input to the Viterbi decoding unit 36 and the Viterbi decoding result is output. However, in order to obtain sufficient reception performance, it is necessary to secure a traceback length that is five times or more the constraint length in the Viterbi decoding process. For some reason, Viterbi decoding cannot be performed without the deinterleave output for the next interleave processing unit. For example, in order to perform Viterbi decoding of the symbol SB1, if the branch metric of the symbol SB2 is not input, the Viterbi decoding result at the end of the data in the interleave processing unit is not output. Since the next symbol SB2 is obtained only after the next interleave data is received and rearranged in the original order, it is necessary to wait until all the next interleave data is received. Accordingly, a waiting time for Viterbi decoding output shown in FIG. 6 occurs, and as a result, the start of interleaving of the iterative decoding unit is delayed. In an apparatus that performs iterative decoding processing, since deinterleaving is performed again after interleaving, the processing delay becomes very large. In IEEE802.11a, the time from when data is received to when the ACK is returned is defined (for example, SIFS: Short Interframe Space), and the iterative decoding process is completed within that time and ACK is transmitted. Although it is necessary, it becomes difficult to return an ACK within a specified time.

  On the other hand, as shown in FIG. 7, MIMO transmitter 10 of the present embodiment generates a transmission frame in which Tail bit TB is inserted at the end of each symbol SB1, SB2,. Interleave in units.

  The MIMO receiver 30 deinterleaves the data transmitted from the MIMO transmitter 10 by the deinterleave unit 35 and outputs the result. In FIG. 7, the deinterleave output processing time is shortened for the same reason as described above. Since all the data for the interleave size is prepared at the start of the deinterleave process, the deinterleave result can be output at high speed. This is because it can.

  In this embodiment, as a result of the deinterleave output, branch metrics obtained from data including the Tail bit TB are arranged in each interleave processing unit. Therefore, the Viterbi decoding unit 36 can complete the Viterbi decoding process in units of interleave processing. As a result, it is possible to quickly start convolutional coding and interleaving for iterative decoding, and to reduce processing delay for iterative decoding.

  By reducing the above iterative decoding processing delay, it is possible to increase the number of times of iterative decoding or increase the time limit for receiving an ACK after receiving data without greatly degrading the transmission efficiency. Furthermore, iterative decoding can be applied in a system where iterative decoding is impossible due to processing delay.

  In the present embodiment, the transmission efficiency that deteriorates due to the insertion of the Tail bit is about 0.3% when assuming transmission in the case of IEEE802.11a with a modulation scheme of 64QAM and a coding rate of 3/4. It is.

(Second Embodiment)
Next, the MIMO transmitter 10 and the MIMO receiver 30 according to the second embodiment of the present invention will be described. The basic configuration of the MIMO transmitter 10 of the second embodiment is the same as that of the MIMO transmitter 10 of the first embodiment, but the transmission frame generation procedure is different. In the second embodiment, instead of adding tail bits to the end of each interleave, bit data of a predetermined length is copied and added from the beginning of the same symbol. The first bit data of the same symbol is known to the receiving apparatus at the time of decoding. In the following description, bit data to be inserted into the interleave is referred to as a known bit.

  FIG. 8 is a flowchart illustrating a transmission frame generation procedure of the MIMO transmitter 10 according to the second embodiment. The basic operation of the MIMO transmitter 10 of the second embodiment is the same as the operation of the MIMO transmitter 10 of the first embodiment. However, in the MIMO transmitter 10 of the second embodiment, After the transmission bits are stored in the FIFO unit 23 (S32), it is different in that it is determined whether or not the number of stored bits in the FIFO unit 23 is (interleave size−number of known bits) (S34). As a result of this determination, if it is determined that the number of accumulated bits is (interleave size−number of known bits) (YES in S34), the known bits are inserted into the FIFO unit 23 (S36).

  FIG. 9 is a diagram illustrating a configuration of the MIMO receiver 30. The MIMO receiver 30 according to the second embodiment includes branch metric insertion units 37 and 49 in addition to the configuration of the MIMO receiver 30 according to the first embodiment. The branch metric insertion unit 37 has a function of inserting a part of the branch metric output from the branch metric calculation unit 34 into the branch metric output from the deinterleaving unit 35.

  FIG. 10 is a diagram illustrating processing of the MIMO transmitter 10 and the MIMO receiver 30 according to the second embodiment. The MIMO transmitter 10 generates a transmission frame according to the flow shown in FIG. In the transmission frame shown in FIG. 10, known bits CB1, CB2,... Are inserted at the end of each symbol SB1, SB2,. This transmission frame is subjected to convolutional coding in interleave units and output in an interleaved manner.

  The branch metric insertion unit 37 of the MIMO receiver 30 divides the branch metric output from the deinterleave unit 35 for each deinterleave processing unit (for example, symbol SB1). The branch metric insertion unit 37 cuts out a predetermined number of branch metrics from the head of the deinterleave processing unit divided and inserts it at the end of the deinterleave processing unit 401. The length of the branch metric cut out here is a length corresponding to a known bit inserted by the MIMO transmitter 30, and has a length corresponding to at least the traceback length. The branch metric insertion unit 37 passes the data into which the branch metric is inserted to the Viterbi decoding unit 36.

  By inserting a branch metric as described above, the inserted branch metric is continuously input to the original Viterbi decoding target data, so that the original Viterbi decoding target data is waited for decoding as in the conventional method. It can be completed without occurring. As a result, iterative decoding interleaving can be started immediately, and iterative decoding processing delay can be reduced.

  In the second embodiment, since no tail bit is inserted, the above processing delay can be reduced while maintaining transmission efficiency.

  In the second embodiment, instead of inserting a Tail bit as in the first embodiment, a past branch metric is input, so Viterbi decoding processing for the inserted branch metric has already been performed. The decoding result of the past branch metric can be used, but the accuracy of decoding depends on the decoding result of the past branch metric.

  The reduction of the above iterative decoding processing delay increases the number of iterative decoding without degrading the transmission efficiency, increases the time limit for receiving data and returning the ACK, and further increases the processing It is possible to make it possible to apply iterative decoding in a system in which iterative decoding is impossible due to delay.

  The wireless transmission device and the wireless reception device of the present invention have been described in detail with reference to the embodiments. However, the present invention is not limited to the above-described embodiments.

  In the above-described embodiment, the MIMO transmitter 10 and the MIMO receiver 30 have been described as examples. However, the present invention can also be applied to other systems that perform convolutional coding, Viterbi decoding, and iterative decoding.

  In the above embodiment, the system using Viterbi decoding has been described. However, the transmission frame generation procedure of the present invention can also be applied to the case of using other error correction codes capable of decoding convolutionally encoded data including Tail bits. is there.

  In the second embodiment described above, the example in which the Tail bit is inserted at the end of the transmission frame has been described, but a known bit may be inserted in the same manner as other symbols.

  According to the present invention, it has an excellent effect of being able to reduce the delay of decoding processing, and is useful as a wireless transmission device including an interference canceller with severe processing delay restrictions.

The figure which shows the transmission frame production | generation procedure of 1st Embodiment The figure which shows the structure of the MIMO transmitter of 1st Embodiment. The figure which shows the structure of the transmission frame production | generation part contained in the MIMO transmitter of 1st Embodiment. The figure which shows the structure of the convolution encoding part contained in the MIMO receiver of 1st Embodiment. The figure which shows the structure of the MIMO receiver of 2nd Embodiment. The figure explaining the problem of the conventional encoding process and decoding process The figure explaining the effect of a 1st embodiment The figure which shows the transmission frame production | generation procedure of 2nd Embodiment The figure which shows the structure of the MIMO receiver of 2nd Embodiment. The figure explaining the effect of 2nd Embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 MIMO transmitter 11 Transmission frame generation part 12 Convolution coding part 13 Interleaving part 14 Mapping part 15 ODFM modulation part 16 RF part 21 Transmission bit generation part 22 Tail bit padding bit insertion control part 23 FIFO part 30 MIMO reception part 31 RF Unit 32 OFDM demodulation unit 33 channel estimation / separation unit 34 branch metric calculation unit 35 deinterleaving unit 36 Viterbi decoding unit 37 branch metric insertion unit 40 iterative decoding unit 41 replica generation unit 42 interference cancellation unit 43 branch metric calculation unit 44 deinterleaving unit 45 Viterbi decoding unit 46 Convolutional encoding unit 47 Interleaving unit 48 Mapping unit 49 Branch metric insertion unit

Claims (7)

A decoding completion bit adding unit for adding a known bit string as a decoding completion bit for enabling decoding processing to the end of a symbol that is an interleaving processing unit;
A convolutional encoding unit for convolutionally encoding the symbol to which the decoding completion bit is added by the decoding completion bit adding unit;
An interleaving unit for interleaving the symbols encoded by the convolutional encoding unit;
A data transmission unit for transmitting data interleaved by the interleaving unit;
A wireless transmission device comprising:   The radio transmission apparatus according to claim 1, wherein the decoding completion bit adding unit adds a predetermined length bit consisting of all 0s as the decoding completion bit to the end of the symbol.   The radio transmission apparatus according to claim 1, wherein the decoding completion bit adding unit duplicates bit data having a predetermined length in the same symbol and adds the duplicated bit data to the end of the symbol. A data receiving unit that receives convolutionally encoded data by adding a known bit sequence as a decoding completion bit for enabling decoding processing to the end of a symbol that is an interleaving processing unit;
A deinterleaving unit that deinterleaves the data received by the data receiving unit for each symbol;
A Viterbi decoding unit for Viterbi decoding the data deinterleaved by the deinterleaving unit for each symbol based on the decoding completion bit;
A wireless receiver comprising: A convolutional encoding unit that performs convolutional encoding of the Viterbi-decoded symbols in the Viterbi decoding unit;
An interleaving unit for interleaving the symbols encoded by the convolutional encoding unit;
A replica signal generation unit that generates a replica signal of the symbol based on the symbols interleaved by the interleaving unit;
An interference cancellation unit that cancels interference of a signal received by the data reception unit by the replica signal generated by the replica signal generation unit;
The wireless receiver according to claim 4, comprising:   The radio reception apparatus according to claim 4, wherein the data reception unit receives convolutionally encoded data in which a predetermined length bit consisting of all 0s is added to the end of the symbol as the decoding completion bit. 5. The radio reception according to claim 4, wherein the data receiving unit replicates bit data having a predetermined length in the same symbol, and receives convolutionally encoded data with the duplicated bit data added to the end of the symbol. apparatus.

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