Design of Low Density Parity Check Codes for Secure and Reliable Communications

Abstract

With the symmetric cryptosystem based on error correcting codes and the concept of equivalent matrix, this paper puts forward a secure communication scheme based on linear block codes. The proposed scheme realizes the secure and reliable integrated communication by hiding and changing the coding matrix (parity check matrix or generator matrix) randomly and simultaneously without decreasing the error correction ability of linear block codes. And also, based on RDF (Random Difference Families), we propose a design method of QC-LDPC codes based on the proposed secure and reliable communication framework. The proposed QC-LDPC codes have a large number of performance equivalent parity check matrix with the same parameters. At the same time, the LDPC codes hold better reliability of transmission and flexibility of design. Finally, the security and reliability of the proposed LDPC codes are verified by analysis and simulations.