Title :
Forced sequence sequential decoding: a concatenated coding system with iterated sequential inner decoding
Author :
Jensen, Ole Riis ; Paaske, Erik
Author_Institution :
Dept. of Telecommun., Tech. Univ., Lyngby, Denmark
fDate :
10/1/1998 12:00:00 AM
Abstract :
We describe a new concatenated decoding scheme based on iterations between an inner sequentially decoded convolutional code of rate R=1/4 and memory M=23, and block interleaved outer Reed-Solomon (RS) codes with nonuniform profile. With this scheme decoding with good performance is possible as low as Eb/N0=0.6 dB, which is about 1.25 dB below the signal-to-noise ratio (SNR) that marks the cutoff rate for the full system. Accounting for about 0.45 dB due to the outer codes, sequential decoding takes place at about 1.7 dB below the SNR cutoff rate for the convolutional code. This is possible since the iteration process provides the sequential decoders with side information that allows a smaller average load and minimizes the probability of computational overflow. Analytical results for the probability that the first RS word is decoded after C computations are presented. These results are supported by simulation results that are also extended to other parameters
Keywords :
Reed-Solomon codes; concatenated codes; convolutional codes; interleaved codes; iterative methods; probability; sequential decoding; SNR; block interleaved outer Reed-Solomon codes; code rate; computational overflow probability; concatenated coding system; convolutional code; cutoff rate; forced sequence sequential decoding; iterated sequential inner decoding; memory; nonuniform profile; outer codes; performance; sequential decoders; side information; signal-to-noise ratio; simulation results; AWGN; Additive white noise; Communications Society; Computational modeling; Concatenated codes; Convolutional codes; Error correction; Helium; Iterative decoding; Signal to noise ratio;
Journal_Title :
Communications, IEEE Transactions on