Optimum and Suboptimum Synchronizer for Binary FSK Communication Systems

This paper considers a binary frequency-shift-keying (FSK) communication system with an adaptive receiver. Partially coherent detection is accomplished exploiting phase and bit synchronization directly extracted from the information-bearing waveform. The optimum (maximum a posteriori probability criterion) estimators of the relevant channel parameters are found along with some suboptimum realizations. It turns out that these schemes are decision-directed tracking systems that may be implemented using standard circuitry.