ML-Performance of Low-Density Parity-Check Codes
نویسندگان
چکیده
In this paper, we derive the maximum likelihood (ML) performance for low-density parity check (LDPC) codes, considering BPSK and QPSK transmission over a Gaussian channel. We compare the theoretical ML performance with the performance of the iterative decoding algorithm. It turns out that the performance of the iterative decoding algorithm is close to the ML performance when the girth of the code is sufficiently high. When the girth of the code is equal to or smaller than 6, the decoding algorithm performs sub-optimal: the bit error rate (BER) obtained with the iterative decoding algorithm is much higher than the optimal BER that can be obtained when using ML decoding.
منابع مشابه
Achieving a near-optimum erasure correction performance with low-complexity LDPC codes
SUMMARY Low-density parity-check (LDPC) codes are shown to tightly approach the performance of idealized maximum distance separable (MDS) codes over memoryless erasure channels, under maximum likelihood (ML) decoding. This is possible down to low error rates and even for small and moderate block sizes. The decoding complexity of ML decoding is kept low thanks to a class of decoding algorithms, ...
متن کاملImproving the Rao-Nam secret key cryptosystem using regular EDF-QC-LDPC codes
This paper proposes an efficient joint secret key encryption-channel coding cryptosystem, based on regular Extended Difference Family Quasi-Cyclic Low-Density Parity-Check codes. The key length of the proposed cryptosystem decreases up to 85 percent using a new efficient compression algorithm. Cryptanalytic methods show that the improved cryptosystem has a significant security advantage over Ra...
متن کاملML and Near-ML Decoding of LDPC Codes Over the BEC: Bounds and Decoding Algorithms
The performance of maximum-likelihood (ML) decoding on the binary erasure channel for finite-length low-density paritycheck (LDPC) codes from two random ensembles is studied. The theoretical average spectrum of the Gallager ensemble is computed by using a recurrent procedure and compared to the empirically found average spectrum for the same ensemble as well as to the empirical average spectrum...
متن کاملA Construction for Low Density Parity Check Convolutional Codes Based on Quasi-Cyclic Block Codes
A set of convolutional codes with low density parity check matrices is derived from a class of quasi-cyclic low density parity check block codes. Their performance when decoded using the belief propagation algorithm is investigated.
متن کاملSearch Based Weighted Multi-Bit Flipping Algorithm for High-Performance Low-Complexity Decoding of LDPC Codes
In this paper, two new hybrid algorithms are proposed for decoding Low Density Parity Check (LDPC) codes. Original version of the proposed algorithms named Search Based Weighted Multi Bit Flipping (SWMBF). The main idea of these algorithms is flipping variable multi bits in each iteration, change in which leads to the syndrome vector with least hamming weight. To achieve this, the proposed algo...
متن کامل