Title :
Generalized product accumulate codes: analysis and performance
Author :
Li, Jing ; Narayanan, Krishna R. ; Georghiades, Costas N.
Author_Institution :
Dept. of Electr. Eng., Texas A&M Univ., College Station, TX, USA
Abstract :
Product accumulate (PA) codes were proposed and shown by Li, Narayanan and Georghiades (see Proc. Intl.. Symp. Inform. Theory, Washington DC, p.122-22, June 2001, and IEEE Tran. Info. Theory) to be a class of simple and provably good codes for rate R⩾1/2. This work investigates the generalized product accumulate (GPA) codes which have rates over the entire range and which are also "good" both in the maximum likelihood (ML) sense and under the iterative approach. Analysis concentrates on the weight distribution over the code ensemble, the ML bounds, and the existence and computation of threshold phenomenon in the iterative decoding. A tight upper bound due to Divsalar (see Proc. 1998 Allerton Conf. Commun. and Control, Sept. 1998, p.201-10) and the thresholds computed using density evolution are examined. Simulations are presented and evaluated, especially for rate R⩽1/2
Keywords :
concatenated codes; convolutional codes; interleaved codes; iterative decoding; maximum likelihood decoding; ML bounds; ML decoding based bounds; code rate; density evolution; generalized product accumulate codes; iterative decoding; maximum likelihood bounds; simulations; threshold phenomenon; thresholds; upper bound; weight distribution; Computational modeling; Concatenated codes; Convolutional codes; Distributed computing; Interleaved codes; Iterative decoding; Iterative methods; Maximum likelihood decoding; Performance analysis; Upper bound;
Conference_Titel :
Global Telecommunications Conference, 2001. GLOBECOM '01. IEEE
Conference_Location :
San Antonio, TX
Print_ISBN :
0-7803-7206-9
DOI :
10.1109/GLOCOM.2001.965563
