MSK and offset QPSK signal transmissions through nonlinear satellite channels in the presence of intersymbol interference

An expression is derived for the bit error probability of minimum shift keying (MSK) and offset quaternary phase shift keying (OQPSK) signals which have been transmitted through nonlinear satellite channels after bandlimiting. The transponder nonlinearity considered in the paper is of the bandpass type, which exhibits AM/AM and AM/PM conversion effects. The effects of up-link and down-link thermal noise are also taken into consideration in the analysis. The resulting expression for the bit error probability is an infinite series containing double integrals. In order to illustrate the usefulness of the method, the error rates of MSK and OQPSK signals are computed for a Butterworth bandlimiting filter hard limiting transponder channel model. The error rates of MSK and OQPSK signals are compared with the error rate of binary PSK signals for this communication system model.