Dissertation > Excellent graduate degree dissertation topics show

LDPC codes in DVB-S2 system

Author: ChenHeXiang
Tutor: ChenWuFan
School: University of Electronic Science and Technology
Course: Pattern Recognition and Intelligent Systems
Keywords: Low-density Parity-check code Digital Video Broadcast-Satellite2 Encoder Low-complexity Belief propagation
CLC: TN938
Type: Master's thesis
Year: 2008
Downloads: 145
Quote: 2
Read: Download Dissertation

Abstract


DVB-S2 (Digital Video Broadcast-Satellite2) is the new generation digital satellite broadcast standard. Compared with DVB-S,It provids many new technical characteristics such as the multi-transmission class input, the adaptive coding modulation (ACM) and the general interface pattern,and also can have better performance and greater flexibility in the condition of effective isotropic radiated power of transmitter. The most noticeable innovation of DVB-S2 lies in the way of channel coding——low-density parity-check code(LDPC).Low-density parity-check code is a type of error correcting block code with sparse check matrix. As LDPC code has better ability of error correcting and closing to the Shannon limit, it is not only accepted by DVB-S2 standarded but also has good prospect of application in some fields, such as high speed wireless network、high speed mobile communication and digital satellite broadcast. However, the existing methods of encoding and decoding of LDPC code have great complexity, it is difficult to achieve in the project. How to reduce the complexity of the LDPC codes becomes hot research in the area of channel coding in recent years. In allusion to problems of LDPC code in DVB-S2 standarded, this paper makes some exploratory reseach in encoding and decoding of LDPC code. The main contents of this paper are as follows:1. As the complexity of LDPC code universal encoding algorithm is in direct proportion to the square of code length, this paper designs one kind of encoder which meets standard request according to the LDPC encoding principle in the DVB-S2 standard. This encoder uses control signal to control generating checking address module and generating checking node module for finishing information collateral process. Then the generating checking bits transmit to repeating module. The codes output through control signal.The encoder uses the special encoding method, therefore it does not need to save the generated matrix, thus reduces the complexity of encoding and can easily realize in the hardware.2. Design a kind of low complexity decoding algorithm. Firstly, Updating checking nodes and information node. In each iteration, all checking nodes receive information from the adjacent information nodes,and then process,transsimit back to adjacent information nodes. Secondly, all information nodes pass the same iterative process. In the iterative decoding process, A simple piecewise linear function substitute for the complex function of containing exponent function and logarithm function.Thirdly, information nodes collect all information and make judgments.Finally, the algorithm was verified in the complexity and the performance.3. This paper designs a module of encoding and decoding LDPC code, which follows the DVB-S2 standard. This process includes: Data source module randomly generate data whose lenth is code length multiplies code ratio; Establishes the BPSK modulation module; Designing the encoding and decoding module. The decoding module uses the low complexity decoding algorithm to complete the corresponding decoding; Using additive white gaussian noise (AWGN) channel. Finally this module is tested to check the performance whether can achieve the DVB-S2 standard the request or not.

Related Dissertations

  1. Research on Techniques of Information Acquisition and Location in Pavement Roughness Inspection,U416.2
  2. The Realization and Study of a Scalable Data Encoder Based on SPIHT,TN762
  3. DM6467 DSP processor- based multi-channel H.264 video encoding software design,TN919.81
  4. Multi- dimensional image based aviation city buildings Recognition Technology,TP391.41
  5. Image restoration of key technologies,TP391.41
  6. Ary LDPC Decoding Algorithm,TN911.2
  7. Research on Repeat Accumulate Decoding Algorithms,TN911.22
  8. LDPC decoder, the realization of research,TN911.22
  9. The Design of the Monitoring System for Urban Public Order Dynamic Video,TP277
  10. The Development Platform Design of Audio Encoder Based on PADK,TN762
  11. Research on CNC of Electromagnetic Pulse Incremental Forming,TP273
  12. VLSI Design and Implementation for Low-complexity LDPC Decoder,TN764
  13. Study on the Mechanism of Busbar Bending and Development of Control System of Busbar Bending Machine,TG305
  14. Compressed video image interpolation based technology research,TP391.41
  15. Study on Low-Complexity Decoding Algorithms for Nonbinary Low-Density Parity-Check Coded-Modulation Systems,TN911.22
  16. The Study of the LDPC Code in DVB-S.2 Standard,TN911.22
  17. The Research on Application and Implementation of CCSDS Image Compression Algorithm,TP391.41
  18. Study of Reduction PAPR of OFDM System,TN919.3
  19. H.264 hardware encoder key technology and DSP codecs to achieve,TN919.81
  20. Design and Implement of Pivotal Technology of IPQAM Physical Layer in FPGA,TN949.2
  21. Target detection based on local features,TP751

CLC: > Industrial Technology > Radio electronics, telecommunications technology > Broadcasting > Satellite broadcasting
© 2012 www.DissertationTopic.Net  Mobile