Quasi-Cyclic LDPC Codes Design Based on an Improved Finite Field Method

This paper proposed a novel QC-LDPC code construction method which combined the finite field method and Tam structure with simple recursive encoding structure.We first construct a parity check matrix by the finite field method,and obtain its corresponding exponent matrix.Then,we use the binary base matrix with the Tam structure to mask with the above exponent matrix.Consequently,a new exponent matrix can be constructed.Finally,a H matrix can be constructed,which is with both the good performance by the finite field method and the simple recursive structure.Simulation results show that the BER of proposed QC-LDPC code is better than the Tam code and 802.16e code.