Channel-estimate-based frequency-domain equalization (CE-FDE) for broadband single-carrier transmission
A channel-estimate-based frequency-domain equalization (CE-FDE) scheme for wireless broadband single-carrier communications over time-varying frequency-selective fading channels is proposed. Adaptive updating of the FDE coefficients are based on the timely estimate of channel impulse response (CIR) to avoid error propagation that is a major source of performance degradation in adaptive equalizers using least mean square (LMS) or recursive least square (RLS) algorithms. Various time-domain and frequency-domain techniques for initial channel estimation and adaptive updating are discussed and evaluated in terms of performance and complexity. Performance of uncoded and coded systems using the proposed CE-FDE with diversity combining in different time-varying, multi-path fading channels is evaluated. Analytical and simulation results show the good performance of the proposed scheme suitable for broadband wireless communications. For channels with high-Doppler frequency, diversity combining substantially improves the system performance. For channels with sparse multi-path propagation, a tap-selection strategy used with the CE-FDE systems can significantly reduce the complexity without sacrificing the performance. Copyright (C) 2004 John Wiley Sons, Ltd.
adaptive equalization frequency-domain equalization (fde) channel estimation (ce) time-varying fading channels ce-based fde