Title :
Concatenated LDPC-TCM coding for reliable storage in multi-level flash memories
Author :
Quan Xu ; Pu Gong ; Chen, Thomas
Author_Institution :
Sch. of Eng. & Math. Sci., City Univ. London, London, UK
Abstract :
In this paper, we present an efficient fault tolerant solution for multi-level per cell (MLC) flash memory that concatenates trellis coded modulation (TCM) with an outer low-density parity-check (LDPC) code. Traditional flash coding systems employ simple hard-decisions based codes, such as Bose-Chaudhuri-Hocquenghem (BCH) codes, that can correct a fixed, specified number of errors. Thanks to the Bahl, Cocke, Jelinek, and Raviv (BCJR) algorithm, the TCM decoder within the proposed design can provide soft decisions which make it possible to use the more powerful LDPC codes. Moreover, the error-correction performance is further improved since TCM can decrease the raw error rate of MLC and hence relieve the burden of outer LDPC code. The effectiveness of concatenated LDPC-TCM systems has been successfully demonstrated through computer simulations.
Keywords :
concatenated codes; error correction codes; fault tolerance; flash memories; multivalued logic circuits; parity check codes; trellis coded modulation; Bose-Chaudhuri-Hocquenghem codes; computer simulations; concatenated LDPC-TCM systems; error-correction performance; fault tolerant solution; low-density parity-check code; multilevel per cell flash memory; trellis coded modulation; Communication systems; Convolutional codes; Decision support systems; Decoding; Flash memories; Modulation; Parity check codes; LDPC codes; error correction; flash memory; soft decisions; trellis coded modulation;
Conference_Titel :
Communication Systems, Networks & Digital Signal Processing (CSNDSP), 2014 9th International Symposium on
Conference_Location :
Manchester
DOI :
10.1109/CSNDSP.2014.6923818
