Threshold Controlled Iterative Channel Estimation for Coded OFDM

In this paper iterative channel estimation (ICE) for coded OFDM systems over dispersive channels is addressed. ICE utilizes data symbol estimates fed back from the channel decoder to refine initial channel estimates obtained by pilot symbols. In the presence of decision feedback errors, the performance of ICE may degrade severely. The proposed threshold controlled ICE avoids decision feedback effects by choosing between iterative and non-iterative channel estimates. The threshold is conditioned on the statistical information of the decoded data at the decoder output, as well as the filter coefficients and the channel statistics.