Hybrid DS/SFH spread-spectrum multiple-access communications over nonselective fading channels

The performance of asynchronous hybrid direct-sequence/slow-frequency-hopped spread-spectrum multiple-access systems over nonselective Rayleigh fading channels is analyzed. We consider binary phase shift keying modulation with coherent demodulation, random spreading code sequences and hopping patterns. As a receiver model, both hard limiting correlation receiver and linear correlation receiver are considered. Bit error probabilities of the systems with/without near-far effect are obtained using a Gaussian interference approximation. The results show that hard limiting receivers are superior to linear correlation receivers over nonselective Rayleigh fading channel