A low complexity space-time equalizer based on tap-mobile for the diversity system

A novel space-time tap-mobile equalizer is proposed as a low complexity solution for diversity receiver operating in wireless frequency selective channels with sparse power profiles. Generally the conventional equalizer requires a large number of filter taps to overcome long delay profiles of the channel multi-paths. However, with the efficient algorithm of channel estimation, time delay and amplitude of all the multi-paths have been known so that the new equalizer just only maintains a small subset of nonzero working taps. As a result, it not only eliminates the noise accumulation effects of the idle taps but also reduces hardware implementation complexity effectively. Moreover this paperpsilas method provides the real-time tracing of variable nonzero tapspsila position fast and flexibly. Simulation results show that this tap-mobile DFE exhibits considerable computational savings and more stable performance than the conventional ones. It is quite fit for applications in high-speed systems, such as high definition television (HDTV) and broadband mobile communication.