TY - GEN
T1 - Pseudo-codeword landscape
AU - Chertkov, Michael
AU - Siepanov, Mikhail
PY - 2007
Y1 - 2007
N2 - We discuss The performance of Low-Density-Parity-Check (LDPC) codes decoded by means of Linear Programming (LP) at moderate and large Signal-to-Noise- Ratios (SNR). Utilizing a combination of the previously introduced pseudocode word-search method and a new "dendro" trick, which allows us to reduce the complexity of the LP decoding, we analyze the dependence of the Frame-Error-Rate (FER) on the SNR. Under Maximum-A-Posteriori (MAP) decoding the dendro-code, having only checks with connectivity degree three, performs identically to its original code with high-connectivity checks. For a number of popular LDPC codes performing over the Additive-White-Gaussian-Noise (AWGN) channel we found that either an error-floor sets at a relatively low SNR, or otherwise a transient asymptote, characterized by a faster decay of FER with the SNR increase, precedes the error-floor asymptote. We explain these regimes in terms of the pseudo-codeword spectra of the codes.
AB - We discuss The performance of Low-Density-Parity-Check (LDPC) codes decoded by means of Linear Programming (LP) at moderate and large Signal-to-Noise- Ratios (SNR). Utilizing a combination of the previously introduced pseudocode word-search method and a new "dendro" trick, which allows us to reduce the complexity of the LP decoding, we analyze the dependence of the Frame-Error-Rate (FER) on the SNR. Under Maximum-A-Posteriori (MAP) decoding the dendro-code, having only checks with connectivity degree three, performs identically to its original code with high-connectivity checks. For a number of popular LDPC codes performing over the Additive-White-Gaussian-Noise (AWGN) channel we found that either an error-floor sets at a relatively low SNR, or otherwise a transient asymptote, characterized by a faster decay of FER with the SNR increase, precedes the error-floor asymptote. We explain these regimes in terms of the pseudo-codeword spectra of the codes.
UR - https://www.scopus.com/pages/publications/51649124277
UR - https://www.scopus.com/pages/publications/51649124277#tab=citedBy
U2 - 10.1109/ISIT.2007.4557442
DO - 10.1109/ISIT.2007.4557442
M3 - Conference contribution
AN - SCOPUS:51649124277
SN - 1424414296
SN - 9781424414291
T3 - IEEE International Symposium on Information Theory - Proceedings
SP - 1546
EP - 1550
BT - Proceedings - 2007 IEEE International Symposium on Information Theory, ISIT 2007
T2 - 2007 IEEE International Symposium on Information Theory, ISIT 2007
Y2 - 24 June 2007 through 29 June 2007
ER -