Fast dual-mode adaptive algorithms for the equalization and timing recovery of TDMA mobile radio signals

Abstract

Adaptive algorithms with rapid convergence properties for the equalization of time division multiple access (TDMA) mobile radio signals are presented. When the symbol timing is known, these algorithms approximate maximum a posteriori (MAP) sequence estimators that generate reliable estimates of the transmitted signal. For channels with timing jitter (from random Doppler shifts), joint estimation of the channel parameters and the symbol timing using an extended Kalman filter (EKF) algorithm is proposed. Various methods to reduce the computational complexity of the MAP sequence estimator are also described.