Serial MSK-type detection of partial response continuous phase modulation

Two minimum shift key (MSK) type receivers, one serial and one parallel, for continuous phase modulation (CPM) are studied. Both receivers are useful for binary modulation schemes with modulation index 1/2. The modulation scheme for the serial receiver is first presented and its performance measurements when no phase or timing errors are present are given. Comparisons with the parallel receiver are made, and the sensitivity of both types to phase errors is derived. It is shown that, assuming perfect phase and time synchronization, both receivers have equal performances. The advantages of the serial receiver over the parallel receiver are the same for partial response CPM as for classical MSK, i.e., both in implementation aspects and in the reduced sensitivity to phase errors.