A simple, intuitive expression for the BER of a jointly optimal single cochannel interferer BPSK receiver

A simple and intuitive new expression for the bit error rate (BER) performance of a synchronous jointly optimum receiver is derived. The receiver is used to detect a binary phase-shift keying (BPSK) signal in the presence of an identical cochannel interferer and additive white Gaussian noise (AWGN). The new expression separates into the BER of BPSK in AWGN plus a term due to the interference. The term due to interference approaches zero when the interference power or its correlation with the desired signal tends to zero, as expected.