SER Computation of MPSK in the Presence of I/Q Mnisatch

The quadrature component unbalance which is generated by a non-ideal component is an inevitable physical phenomenon and leads to performance degradation when we implement a practical coherent M-ary phase shift keying (MPSK) demodulator. In this paper, we derive a general expression involving a two-dimensional joint Gaussian Q-function for the symbol error rate (SER) of an MPSK signal with the quadrature component unbalance over additive white Gaussian noise (AWGN) channel.