http://www.paper.edu.cn E-mailxiefei_307@163.com TN 1. LDPCLow Density Parity Check Gallager LDPC LDPC DVB-S2 LDPC Turbo LDPC LDPC LDPC 1 2 DTTB[1] 1

http://www.paper.edu.cn 2. nu mnu mnv [2] u n log( 1 P n 1 P n 2 y n ) 2 u mn log( R R 1 mn 1 mn ) tanh( u mn 2 ) ( nmNk \) tanh( v mk 2 ) v mn log( Q Q 1 mn 1 mn ) u n u \)( mnMl ln v n log( Q 1 n 1 Q n ) u n x n sign ( n v ) u )( nMm mn log-BP u mn sign u k N m n ( )\ ( ) min ( k N m n )\ ( mn abs u ( ) ) mn BP 0.3-0.4 dB 2

http://www.paper.edu.cn 3. FPGA DTTB 0.4 30487493 AWGN BPSK matlab C 0.8 100 30 8128868 bit ram bit 3

http://www.paper.edu.cn 8bit 12bit 8bit 8bit 10 -6 10 -3 6bit 8bit 0.2dB 88 2.5dB 812 2.6dB 2.7dB 68 2.7dB 0 1 88 68 4

http://www.paper.edu.cn 4. LDPC LDPC S 20068 [2] LDPCA The Research of LDPC Quantification in DTTB system Multimedia Communication Lab, Beijing University of Posts and Telecommunication Beijing, Xie Fei PRC(100876) Abstract The LDPC(Low-Destiny Parity-Check) code is an important code in the field of the Channel Coding. Because it’s performance in theory nearer to Shannon Limit, more and more people pay attention to this code. A lot of paper analysis the qualification method using log-BP arithmetic. This paper mainly talks about the qualification method using min-sum arithmetic in DTTB system, simulation the performance in AWGN channel, BPSK modulation. Because the min-sum arithmetic is much easier than the log-BP arithmetic in the hardware implementation, reasonable and easy qualification method can provide theory assurement. Key words: LDPC min-sum DTTB Quantification 1983 LDPC 5