Encrypting LDPC-Codec

The presented LDPC-codec has no encrypting function since its rediscovering, and the presented encrypting for signal transmission needs additional algorithm and program, which leads the great time delay for the signal receiving. This paper reveals that LDPC-codec itself can have the desired encrypting faction if adopting our processing approach for the generator matrices of transmitters and parity matrices of receivers, without additional and special encrypting program. Because the proposed encrypting is at the level of channel coding, it is difficult for illegal users to filch the transmitted data in wireless channel. The encrypting scheme lets encrypted parity-check matrix of LDPC codec and encrypted outer interleavers as secret keys for legal users. Since it based LDPC, the system has the performance of anti-jamming, and the presented encrypting schemes have no such function. The simulation verified the effect of encryption and the validity of the presented approach of the paper