A Comparative Study of Two Ada.ptive Equalizers for Mobile Radio

This paper presents a. study of adaptive equalization techniques designed to improve bit error rates (BER) degraded by multipath propagation in · mobile communication systems. Two kinds of equalizers are used in simulation: adaptive lattice decision feedback equalizer (L-DFE) and maximum likelihood sequence estimation (MLSE). RLS algorithms are used to update the equalizers. The choices are based on the fact that a DFE has little noise enhancement and a RLS algorithm converges fast and has good tracking capability. The sensitivities of these equalizers to receiver-velocity and ·.signal-to-noise (SNR) are tested for a two ray multipath channel, where the ratio of powers of the rays can vary. Results. show that these two kinds of eq'!lalizers have similar performance.