Doppler spread estimation for nonRayleigh fading channel

A method for estimating the Doppler spread in mobile orthogonal frequency division multiplexing (OFDM) systems is described. The estimation is based on phase message of time domain channel estimation over several OFDM symbols. In OFDM systems, channel estimation is popularly performed in frequency domain. Channel frequency response estimates are affected by noise and inter-carrier interference (ICI). As a result, Doppler estimation is useful to improve CIR performance. In this paper, methods of partial maximal path and path tracing have been presented. Furthermore estimation bias is analyzed and error correcting modified method is advised to reduce estimation precision. All of these measures improve the estimator and the performance can not be influenced by signal-to-noise ratio (SNR). The algorithm is verified with digital terrestrial multimedia broadcast (DTMB) platform and simulation results show good estimation performance. In addition, this estimator is of robust in a wide range of Doppler spread and SNR.