On the Performance of Single-Channel Source Separation of Two Co-Frequency PSK Signals with Carrier Frequency Offsets

Single-channel blind source separation (SCBSS) of uncoordinated, non-spread, co-frequency interfering signals with non-zero carrier frequency offset (CFO) and timing offset, and without training sequence for channel estimation, is a challenging task. To measure the impact of different parameters on the performance of the separated signal, most of the previous works rely on numerical evaluations. In this paper, the union bounds of the symbol error rates (SERs) of the separated symbols from the mixture of two PSK signals of different powers and initial phases, with and without carrier frequency offsets (CFOs), are derived. Simulation results show that the SER bounds are tight in high SNR region. Based on the SER bounds, the effects of power, phase and CFO on the SER of the stronger and weaker signals are discussed.