Performance of a coded hybrid spread spectrum communication system in the presence of partial band noise and multiple access interference

The authors evaluate the performance of a hybrid direct-sequence/frequency-hopped spread-spectrum communication system in the presence of partial band interference, multiple-access interference and additive white Gaussian noise. The system uses an MFSK modulator ( M⩾2) and a noncoherent demodulator with forward error correction. Several forward-error-control coding schemes have been considered to improve the performance of the system. These schemes either reduce the signal-to-noise ratio required to achieve a desirable bit error rate with fixed number of users, frequency slots, and code rate, or they increase the number of users of the network with the rest of the system parameters fixed. It was also shown that partial band interference substantially degrades the performance of the hybrid multiple-access system