MP-WFRFT and constellation scrambling based physical layer security system

In this paper, a multiple parameters weighted fractional Fourier transform (MP-WFRFT) and constellation scrambling (CS) method based physical layer (PHY) security system is proposed. The proposed scheme is executed by two steps. In the first step, MP-WFRFT, implemented as the constellation beguiling (CB) method, is applied to change the signal's identity. In the second step the additional pseudo random phase information, regarded as the encryption key, is attached to the original signal to enhance the security. Typically, the pseudo random phase information can be removed effectively by the legitimate receiver. In contrast to the cryptography based encryption algorithms and the conventional PHY secrecy techniques, the main contribution of the proposed scheme is concentrated on the variation in signal's characteristics. Simulation results show that the proposed scheme can prevent the exchanging signal from eavesdroppers' classification or inception. Moreover, the proposed scheme can guarantee the BER performance at a tolerate increasing in computational complexity for the legitimate receivers.