A speed estimation based two-stage symbol aided channel estimator for frequency nonselective variant fading channel

In this paper, we propose an algorithm for tracking the phase and amplitude of frequency nonselective fading channels. In contrast to conventional channel estimation techniques, which do not take enough advantage of the statistical characteristics of the received radio signal, this algorithm combines a conventional channel estimator with a speed estimator which can adaptively control the mode of the interpolation technique, the bandwidth of the smoothing filter or the step length of the adaptive filter (e.g. the LMS algorithm) in order to track the variant fading channel. Simulation results demonstrate the improved performance of this algorithm compared with the conventional channel estimator under the variant fading channel