An adaptive hidden Markov model/Kalman filter algorithm for narrowband interference suppression with applications in multiple access communications

This paper presents a novel nonlinear filter for narrowband interference suppression in multiple access communication systems; in particular code division multiple access spread spectrum. The proposed algorithm combines a recursive hidden Markov model estimator, Kalman filter and the recursive expectation maximization algorithm. It is shown that the proposed algorithm outperforms current linear and nonlinear filtering techniques, presented by Rusch and Poor (see IEEE Transactions on Communications, vol.42, no.2/3/4, p.1969-79, 1994)