Demodulation of cochannel FSK signals using joint maximum likelihood sequence estimation

This paper describes a technique for demodulating cochannel Manchester-encoded, frequency-shift-keyed (MEFSK) signals even when the two signals have equal power. Both data sequences are recovered. The technique is based on joint maximum likelihood sequence estimation (JMLSE). The Viterbi algorithm is used to minimize the computational requirements. Adaptive loops track the transmitter carrier and filtering characteristics. The demodulator performance is evaluated as a function of baudrate offset, carrier power separation and additive noise