Abstract: A novel modulation and demodulation structure based on binary differential stochastic process shift keying (BDSPSK) is proposed. The theoretical bit error rates (BER) under the Gaussian and quasi-static Rayleigh fading channels are derived, respectively. To verify its performances and security, lots of simulations are done by using MATLAB. The simulations’ results show that the BER of the proposed BDSPSK can reach 10?4 when signal to noise ratio (SNR) is about ?2 dB in the Gaussian channel or 25 dB in the Rayleigh fading channel. Meanwhile, the proposed method has a good concealment due to its undetectable property by the generalized second order cyclostationary spectrum, which makes it suit for secure communi-cations in the physical layer.