Geometrically-structured maximum-girth LDPC block and convolutional codes
IEEE Journal on Selected Areas in Communications - Special issue on capaciyy approaching codes
An efficient on-the-fly encoding algorithm for binary and finite field LDPC codes
IEEE Communications Letters
A lattice-based systematic recursive construction of quasi-cyclic LDPC codes
IEEE Transactions on Communications
A parallel layered decoding algorithm for LDPC codes in WiMax system
WiCOM'09 Proceedings of the 5th International Conference on Wireless communications, networking and mobile computing
A class of QC-LDPC codes with low encoding complexity and good error performance
IEEE Communications Letters
Construction of nonbinary quasi-cyclic LDPC cycle codes based on singer perfect difference set
IEEE Communications Letters
A low-complexity rate-compatible LDPC decoder
Asilomar'09 Proceedings of the 43rd Asilomar conference on Signals, systems and computers
Scheduling for an adaptive number of iterations in turbo equalizers combined with LDPC decoders
IEEE Transactions on Communications
Large-girth nonbinary QC-LDPC codes of various lengths
IEEE Transactions on Communications
| Hi-index | 754.84 |
In this correspondence we present a special class of quasi-cyclic low-density parity-check (QC-LDPC) codes, called block-type LDPC (B-LDPC) codes, which have an efficient encoding algorithm due to the simple structure of their parity-check matrices. Since the parity-check matrix of a QC-LDPC code consists of circulant permutation matrices or the zero matrix, the required memory for storing it can be significantly reduced, as compared with randomly constructed LDPC codes. We show that the girth of a QC-LDPC code is upper-bounded by a certain number which is determined by the positions of circulant permutation matrices. The B-LDPC codes are constructed as irregular QC-LDPC codes with parity-check matrices of an almost lower triangular form so that they have an efficient encoding algorithm, good noise threshold, and low error floor. Their encoding complexity is linearly scaled regardless of the size of circulant permutation matrices.