Structure and performance analysis of an SS-based digital modulation system

In this study, the parameter of a symmetric -stable (SS) noise sequence is modulated by the binary message sequence to achieve a secure communication system. The characteristic exponent ' of an SS noise sequence carries the binary information. In order to recover the binary message sequence at the receiver, the authors propose a logarithmic moments estimator to estimate the characteristic exponent ' of the transmitted noise sequence. The optimal decision threshold and the minimum theoretical bit error ratio are derived. It is shown that the simulation results of the presented logarithmic moments estimator are consistent with the analytical results. Moreover, this estimator shows better performance and lower computational complexity than the conventional SINC estimator based on the fractional low-order moment method.