Channel Coding Using LFSR Based Symmetric Cryptography

Advances in communication technology have seen strong interest in digital data transmission. However, illegal data access has become more easy and prevalent in wireless and general communication networks. In order to protect the valuable data from illegal access, different kinds of cryptographic systems have been proposed. In this paper, a new integrating channel coding and cryptography design communication systems is proposed. In order to preserve the advantages of encryption, improve its disadvantages, and combine the channel coding and cryptography, we place the encryptor before the hamming encoder to select the generator matrix to be used for block code to form the new system. The analysis indicates the proposed design possesses the following feature. Its security is higher than the conventional one with the channel encoder only. Privacy is more due to unknown random codes. As the applied codes are unknown to a hostile user, this means that it is hardly possible to detect the message of another user. Anti-jam performance is good. It overcomes the disadvantage of Chaos based cryptography system as input data is not extended and hence bandwidth is not wasted. Moreover, the computer simulation shows that the proposed system has a good ability in error detection especially when the SNR per bit is moderate high, and the detection ability is enhanced when the increased length of Hamming code is employed