Optimum Demodulation in Pulse Communication Systems Employing Secondary Frequency Modulation

In this paper we examine the problem of optimum demodulation of a class of pulse modulation schemes that employ Secondary frequency modulation-frequently used in satellite data transmission and remote control systems. We develop approximate zero-lag and finite-lag receivers using approximate nonlinear filtering and smoothing techniques and study their steady-state behavior for various pulse modulation schemes. Comparisons of performance are also presented, between the zero-lag and finite-lag receivers on the one hand and between various primary modulation schemes on the other.