New physical layer encryption algorithm based on DFT-S-OFDM system

Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing(DFT-S-OFDM) is widely applied to the next generation wireless communication, because of its good performance in band utilization, high ability to resist multipath interference, low peak to average power ratio and low emitted energy. Traditional data security methods can not effectively protect the air interface and implement complex. This paper proposed a new physical layer encryption algorithm. The algorithm utilized the initial value of chaotic sequence as seed key, under its control produced two complex diagonal key matrices, multiplied by the two matrices respectively before and after the N-point DFT transform, through this method we implement the data encryption. The algorithm is easy to implement, does not change the PAPR of original system and bit error rate of the system, can resist brute-force attack and plaintext cipher-text attack.