Abstract
In this thesis, we developed a method for obtaining near-optimal sequence estimates in the presence of interference for direct sequence spread spectrum communication using the Expectation-Maximization (EM) algorithm. We assume binary phase shift keying (BPSK) signaling in the presence of additive white Gaussian noise (AWGN) and single tone interference. The algorithm developed here is shown to have a complexity that grows linearly as a function of sequence length. We investigate the system performance in terms of bit error rate (BER) for single tone interference with both random phase and amplitude. We compare the algorithm with the suboptimal approach of using a digital transversal filter as a notch filter. Finally we present simulation results and draw conclusions.
Zhang, Quan G (1996). Sequence estimation in the presence of interference via the expectation-maximization algorithm. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1996 -THESIS -Z416.