Performance evaluation of a direct-sequence spread-spectrum multiple-access system with microscopic and macroscopic diversity in mobile radio environment

Bit error rates of a direct-sequence spread-spectrum multiple-access (DS/SSMA) system employing microscopic and macroscopic diversity in conjunction with forward error correction (FEC) channel coding are evaluated. The radio link is modeled as an additive white Gaussian noise channel with Rayleigh fading and log-normal shadowing. The performance of the maximal ratio combining (MRC) with coherent binary phase shift keying (BPSK) demodulation is compared with that of the postdetection combining with noncoherent differential phase shift keying (DPSK) demodulation, in which these two types of microscopic diversities are combined with macroscopic selection diversity.