WO2003024043A1 - Procede et systeme de decodage de canal base sur la combinaison d'un code de convolution discontinu et d'une modulation d'amplitude en quadrature - Google Patents

Procede et systeme de decodage de canal base sur la combinaison d'un code de convolution discontinu et d'une modulation d'amplitude en quadrature Download PDF

Info

Publication number
WO2003024043A1
WO2003024043A1 PCT/CN2001/001269 CN0101269W WO03024043A1 WO 2003024043 A1 WO2003024043 A1 WO 2003024043A1 CN 0101269 W CN0101269 W CN 0101269W WO 03024043 A1 WO03024043 A1 WO 03024043A1
Authority
WO
WIPO (PCT)
Prior art keywords
branch metric
value
corpse
bits
modulation
Prior art date
Application number
PCT/CN2001/001269
Other languages
English (en)
Chinese (zh)
Inventor
Huixia He
Yongsheng Zhang
Original Assignee
Linkair Communications, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Linkair Communications, Inc. filed Critical Linkair Communications, Inc.
Priority to PCT/CN2001/001269 priority Critical patent/WO2003024043A1/fr
Priority to CN01817822.7A priority patent/CN1211986C/zh
Publication of WO2003024043A1 publication Critical patent/WO2003024043A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
    • H04L1/0056—Systems characterized by the type of code used
    • H04L1/0059—Convolutional codes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
    • H04L1/0045—Arrangements at the receiver end
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
    • H04L1/0056—Systems characterized by the type of code used
    • H04L1/0067—Rate matching
    • H04L1/0068—Rate matching by puncturing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
    • H04L1/0056—Systems characterized by the type of code used
    • H04L1/0071—Use of interleaving

Definitions

  • the present invention relates to the field of communication technology, and in particular, to a channel decoding method and system based on a combination of Punctured Convolution Code and QAM modulation in a communication system.
  • Digital communication systems are concerned with how to increase the throughput of transmitted data at a given signal-to-noise ratio (SNR).
  • Error correction codes are an important means to improve the reliability of information transmitted in communication systems.
  • the use of error correction codes (such as convolutional codes) enables the system to achieve the same error code with a lower signal-to-noise ratio (SNR) or a higher data rate. Rate (BER).
  • SNR signal-to-noise ratio
  • BER Rate
  • the reduction in the signal-to-noise ratio is often referred to as the coding gain.
  • the coding gain can be determined by the bit error rate performance curve.
  • the performance curves for non-coding and various coding rates are based on Eb / NO, where Eb is the power of the bit, and NO is the unilateral power spectral density of white Gaussian noise.
  • the coding gain is the difference between the abscissa Eb / NG values corresponding to the coding and non-coding curves for a given BER.
  • the convolutional encoder and Viterbi decoder are defined by the coding rate and the degree of constraint.
  • the coding rate (m / n) represents n codewords corresponding to the output produced by the encoder, and m bits are input at the input end.
  • the constraint degree K is the number of registers of the convolutional encoder plus one.
  • the basic idea of the Viterbi (VB) decoding algorithm is to receive a coded codeword information stream with noise, and use the state transition lattice of the convolutional code to efficiently calculate and update the conditional probability of two states to search for one.
  • Maximum Likelihood Path where k is the constraint degree.
  • the conditional probability of each set of input bits ⁇ -1 state needs to be calculated.
  • the decision value calculated each time is stored in the path memory in one bit.
  • the storage depth of the path memory should be large enough so that the probability of selecting the path approaches 1.
  • the selectable path length is about 5K.
  • the preferred path length for a CRC with a code rate of 2/3 should be increased accordingly.
  • QAM Quadrature Amplitude Modulation
  • QAM Quadrature Amplitude Modulation
  • the received metric signal information is used to first calculate the branch metric value of the input bit at each moment according to the known encoding method and truncation matrix. , And then input to the decoder to search for a maximum likelihood path, which is the estimated value of the transmitting bit sequence.
  • a maximum likelihood path which is the estimated value of the transmitting bit sequence.
  • the object of the present invention is to provide a new channel decoding method and system based on the combination of signal-added punctured convolutional codes and QAM modulation.
  • a channel decoding method based on a combination of a supplemental punctured convolutional code and QAM modulation including:
  • the input information bits are sent by the sender; the input bits are coded by convolutional code with enhanced puncturing; the coded bits are converted into symbols; the symbols are interleaved; the signals are modulated by QAM modulation and sent;
  • the received modulation signal is deinterleaved in a manner corresponding to the interleaving manner at the transmitting end; the branch metric value required for decoding is determined; and the deinterleaved Decode the modulated signal; output the estimated value of the input bits at the transmitting end;
  • a signal transmission and reception system for implementing the above channel decoding method, which includes a signal transmission device and a reception device, wherein the transmission device includes a signal input device, and a letter-added punctured convolutional code.
  • the information bits of the transmitting device are increasing Encoded in a punctured convolutional code encoder and converted to a symbol in a symbol converter; interleaves the symbol in an interleaver, modulates it in a QAM modulator, and sends it; the receiving device divides the received modulated signal in The interleaver corresponding to the interleaver at the transmitting end is deinterleaved.
  • the deinterleaved data is used to calculate the branch metric value in the branch metric calculator, and the output result is used for decoding at the VB soft decision decoder to search the transmitting end Encode the maximum likelihood path of the bit sequence and output the estimated value of the input bit at the transmitting end,
  • the branch metric value required for decoding is determined in the branch metric calculator, the predicted intercept matrix and the spatial coordinate information of the modulation signal are used, and when calculating the branch metric value at the intercept, the real part, the imaginary part, Departments are calculated separately.
  • the channel decoding method and system of the present invention under the same conditions (the same low-rate encoder, the same coding rate, the same truncation matrix, and the same modulation method), it can be compared with other methods (common methods described above) and systems Bring more coding gain, meanwhile, the calculation complexity is reduced, and the design complexity of related equipment is simplified, and the efficiency of the communication system is improved.
  • BRIEF DESCRIPTION OF THE DRAWINGS The specific embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
  • FIG. 1 Structure of a preferred embodiment transmitter
  • FIG. 2 Structure of a preferred embodiment receiver
  • FIG. 3 R-16QAM modulation constellation diagram used in the preferred embodiment of the present invention.
  • FIG. 5 R-64QAM modulation constellation diagram used in the preferred embodiment of the present invention. detailed description
  • the channel decoding method based on the combination of the supplemental punctured convolutional code and QAM modulation of the present invention determines the branch metric value required in the decoding process by making full use of the information provided by the coding and modulation modes.
  • branch metric values the real and imaginary parts of the signal information are processed separately, reducing unnecessary calculations, simplifying the design complexity of the corresponding equipment, and improving the transmission efficiency of the communication system.
  • a bit stream is input to the augmented punctured convolutional encoder, the bit synthesized symbols are encoded, and symbol interleaving is performed. , And then enter the QAM modulator to perform modulation in a specific way.
  • the receiving end deinterleaves the received signal real and imaginary values and inputs them to the branch metric calculator.
  • the VB soft decision decoder uses the branch metric to calculate the output metric value step by step. Decode and output the estimated value of the originating bit.
  • FIG. 1 illustrates a transmitter structure according to a preferred embodiment of the present invention.
  • an input bit stream ⁇ 2 ... from a signal input device (not shown) is encoded by the encoder 1.
  • the rate of the letter-added punctured convolutional coding is 2/3.
  • the output coded bits are combined into one symbol every S bits.
  • the R-16QAM modulation mode corresponding to this embodiment 4.
  • interleaving The role of interleaving is to improve the adjacent spacing between related signals that are transmitted. When a burst of errors occurs, interleaving can spread these burst errors to irrelevant symbols, thereby improving the error correction capability of the Viterbi decoder.
  • a set of symbols via the interleaver 4 is sent to the R-16QAM modulator 5 to generate a modulated signal.
  • the constellation diagram used in the preferred embodiment is shown in FIG. There is a certain mapping relationship between the horizontal and vertical coordinate values of the modulated signal and the coded bits. This relationship is determined by the augmented signal pruning matrix P and the modulation method. It is specifically used and reflected in the following decoding process.
  • FIG. 2 shows a structure of a receiver according to a preferred embodiment of the present invention.
  • the receiver deinterleaves the real and imaginary values of the received noisy signal and inputs it directly into the branch metric calculator.
  • the VA decoder (according to the pre-known truncation method) processes the metric value output from the branch metric calculation, decodes it step by step, and outputs the estimated value of the originating bit.
  • the receiver inputs the received noisy signals into the deinterleavers 7 and 8 respectively.
  • the truncation matrix PM (the period is P) is expressed as: (p u , pMp 2 consultp 22 ) ... (p Pi , P P 2) Two columns with only one 0 in one column are adjacent.
  • the truncation matrix is (1011, 1101), which corresponds to the truncation method of the two output ports of the 1/2 rate convolutional coding. Where 0 means delete and 1 means keep.
  • the deinterleaved received signal ⁇ ) is sent to the branch metric calculator 9, and the calculated branch metric value is input to the VB soft decision decoder 10.
  • the branch metric used by the decoder is based on the following considerations.
  • the coordinates of 16QAM modulated signal vector endpoints in the signal space are determined by the input information data.
  • the real and imaginary parts of the modulation constellation are independent of each other.
  • the correspondence between the two coded bits generated by the encoder and the real or imaginary part of the constellation is shown in Table 1 below:
  • the symbol value of the coordinate value corresponding to the first codeword in the two codewords (0 corresponds to positive, 1 corresponds to negative); the absolute value of the coordinate value corresponding to the second codeword (0 corresponds to 3.0 a, 1 corresponds to 1.0a).
  • the parameter a is determined by the average power of the signal.
  • the calculation method of the branch metric value is described in detail.
  • the processing period of the preferred embodiment of the present invention is 3.
  • the branch metric values on the state transition diagram corresponding to the input three bits are:
  • ⁇ 1 (1) ⁇ ⁇ ( ⁇ + 3.0 ⁇ ) 2 , ( ⁇ + 1.0 ⁇ ) 2 ⁇
  • the branch metric values on the state transition diagram corresponding to the input three bits are:
  • the advantages of the present invention are: (1) The number of branch metrics calculated in advance is the same as the existing decoding method, but the calculation of each branch metric is greatly reduced in the number of comparison distances, which is only 1/4 of the original. This is because in the calculation of the branch metric value, the information of the modulation method and the truncation matrix is fully utilized, so that the calculation is relatively simple and effective compared to the commonly used decoding method, and the number of comparisons required is also reduced, increasing The calculation speed is calculated.
  • the processing in the VB soft-decision decoder 10 is also quite simple. It only needs to know the two coded bits after inputting 0 or 1 in various states, which is the same as the hard-decision memory requirements. At each decoding moment, corresponding to each current state and input bit, combined with the truncation rule, the required branch metric value is read out from the branch metric value memory, an optimal path is searched out, and an estimation of the encoding bit at the sending end is given. value.
  • the specific way to read data is shown in the above method.
  • the modulation constellation diagram of the R-6 4 QAM shown in FIG. 5, and the branch metric used by the decoder is based on the following considerations.
  • the coordinates of the endpoints of the 64QAM modulated signal vector in the signal space are determined by the input information data.
  • the real and imaginary parts of the modulation constellation are independent of each other.
  • the correspondence between the three coded bits generated by the encoder and the real or imaginary part of the constellation is shown in Table 2 below: 000 7.
  • Table 2 As can be seen from Table 2, the first codeword of the three codewords corresponds to the symbol value of the coordinate value, (G corresponds to positive, 1 corresponds to negative); the last two codewords correspond to The absolute value of the coordinate value (00 corresponds to 7.0a, 01 corresponds to 5.0a, 11 corresponds to 3.0a, and 10 corresponds to 1.0a). The parameter a is determined by the average power of the signal. In the same way as above, the required branch metric value can also be simply calculated.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Error Detection And Correction (AREA)

Abstract

La présente invention concerne un procédé et un dispositif de décodage de canal. Dans l'émetteur, des bits d'entrée sont codés sur la base d'un code de convolution discontinu, les symboles synthétisés avec les bits codés sont entrelacés, puis fournis à un modulateur de modulation d'amplitude en quadrature. Dans le récepteur, le signal reçu est désentrelacé et les données désentrelacées sont décodées afin de produire les valeurs évaluées des bits codés, les valeurs de mesure de branchement sont obtenues par traitement de la partie réelle et de la partie imaginaire du signal reçu utilisant respectivement les informations et le mode de modulation et des matrices à bits tronqués. Par rapport aux autres procédés de décodage, le calcul selon la présente invention est simple et améliore l'efficacité du système de communication.
PCT/CN2001/001269 2001-08-24 2001-08-24 Procede et systeme de decodage de canal base sur la combinaison d'un code de convolution discontinu et d'une modulation d'amplitude en quadrature WO2003024043A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/CN2001/001269 WO2003024043A1 (fr) 2001-08-24 2001-08-24 Procede et systeme de decodage de canal base sur la combinaison d'un code de convolution discontinu et d'une modulation d'amplitude en quadrature
CN01817822.7A CN1211986C (zh) 2001-08-24 2001-08-24 基于增信删余卷积码与qam调制相结合的信道译码方法和系统

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2001/001269 WO2003024043A1 (fr) 2001-08-24 2001-08-24 Procede et systeme de decodage de canal base sur la combinaison d'un code de convolution discontinu et d'une modulation d'amplitude en quadrature

Publications (1)

Publication Number Publication Date
WO2003024043A1 true WO2003024043A1 (fr) 2003-03-20

Family

ID=4574848

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2001/001269 WO2003024043A1 (fr) 2001-08-24 2001-08-24 Procede et systeme de decodage de canal base sur la combinaison d'un code de convolution discontinu et d'une modulation d'amplitude en quadrature

Country Status (2)

Country Link
CN (1) CN1211986C (fr)
WO (1) WO2003024043A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110958025A (zh) * 2019-12-17 2020-04-03 中山大学 一种基于叠加的短帧长编码及译码方法
CN114553244A (zh) * 2022-01-19 2022-05-27 北京理工大学 低码率Turbo码译码方法和装置

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102055557B (zh) * 2010-12-29 2013-03-06 北京星河亮点技术股份有限公司 适用于qam调制的4×4sast编码的译码方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5848102A (en) * 1993-06-04 1998-12-08 Qualcomm Incorporated Method and apparatus for encoding/decoding QAM trellis coded data
EP0930738A2 (fr) * 1998-01-13 1999-07-21 Lucent Technologies Inc. Codes complémentaires de convolution optimales et a perforation pour l'utilisation dans la radiodiffusion numérique et d'autres applications
EP1014590A2 (fr) * 1998-12-21 2000-06-28 Lucent Technologies Inc. Codes complémentaires de convolution optimales

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5848102A (en) * 1993-06-04 1998-12-08 Qualcomm Incorporated Method and apparatus for encoding/decoding QAM trellis coded data
EP0930738A2 (fr) * 1998-01-13 1999-07-21 Lucent Technologies Inc. Codes complémentaires de convolution optimales et a perforation pour l'utilisation dans la radiodiffusion numérique et d'autres applications
EP1014590A2 (fr) * 1998-12-21 2000-06-28 Lucent Technologies Inc. Codes complémentaires de convolution optimales

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110958025A (zh) * 2019-12-17 2020-04-03 中山大学 一种基于叠加的短帧长编码及译码方法
CN110958025B (zh) * 2019-12-17 2023-03-31 中山大学 一种基于叠加的短帧长编码及译码方法
CN114553244A (zh) * 2022-01-19 2022-05-27 北京理工大学 低码率Turbo码译码方法和装置
CN114553244B (zh) * 2022-01-19 2024-06-04 北京理工大学 低码率Turbo码译码方法和装置

Also Published As

Publication number Publication date
CN1471780A (zh) 2004-01-28
CN1211986C (zh) 2005-07-20

Similar Documents

Publication Publication Date Title
Li et al. Trellis-coded modulation with bit interleaving and iterative decoding
Li et al. Bit-interleaved coded modulation with iterative decoding and 8 PSK signaling
Liew et al. Space-time codes and concatenated channel codes for wireless communications
Woodard et al. Comparative study of turbo decoding techniques: An overview
US7568147B2 (en) Iterative decoder employing multiple external code error checks to lower the error floor
US7992073B2 (en) Decoding device, decoding method, and receiving apparatus
US7627803B2 (en) System and method for variable forward error correction (FEC) protection
Hyun et al. Bit metric generation for Gray coded QAM signals
US8358713B2 (en) High throughput and low latency map decoder
Abdelaziz et al. Ternary convolutional codes for ternary phase shift keying
Fowdur et al. Performance of LTE turbo codes with joint source channel decoding, adaptive scaling and prioritised QAM constellation mapping
WO2003024043A1 (fr) Procede et systeme de decodage de canal base sur la combinaison d'un code de convolution discontinu et d'une modulation d'amplitude en quadrature
WO2017214860A1 (fr) Procédé et dispositif de démodulation et de décodage
Fowdur et al. Performance of Turbo coded 64-QAM with joint source channel decoding, adaptive scaling and prioritised constellation mapping
Wahlen et al. Turbo coding applied to pragmatic trellis-coded modulation
Sayhood et al. Performance analysis of punctured convolutional codes and turbo-codes
KR20090014905A (ko) 네트워크 부호화 장치 및 방법
Lamy et al. Low complexity iterative decoding of variable-length codes
EP0949779A2 (fr) Méthode et dispositif de codage
Chen et al. Constrained decoding for turbo-CRC code with high spectral efficient modulation
Yuan et al. Turbo-coded M-QAM for fading channels
Ng et al. A turbo-detection aided serially concatenated MPEG-4/TCM videophone transceiver
KR100586836B1 (ko) 비터비 디코더
Muduli et al. Performance of Turbo codec OFDM in Rayleigh Fading Channel for wireless communication
Park et al. Performance of turbo coded modulation schemes in frequency selective Rayleigh fading channels

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BY BZ CA CH CN CO CR CU CZ DE DM DZ EC EE ES FI GB GD GE GH HR HU ID IL IN IS JP KE KG KP KR LC LK LR LS LT LU LV MA MD MG MN MW MX MZ NO NZ PH PL PT RO SD SE SG SI SK SL TJ TM TR TT TZ UG US UZ VN YU ZA

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ UG ZW AM AZ BY KG KZ MD TJ TM AT BE CH CY DE DK ES FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW MR NE SN TD TG

WWE Wipo information: entry into national phase

Ref document number: 018178227

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP