A joint algorithm of iterative equalization and iterative channel estimation in SC-FDE system

Abstract

The channel estimation accuracy has great impact on the bit error ratio performance of the single-carrier broadband wireless communication system. In order to enhance the channel estimation accuracy when the length of pilot is limited, a joint algorithm of iterative equalization and iterative channel estimation is proposed. This algorithm makes use of the iterative block feedback equalization (IB-DFE) to combat the serious effect of the channel's deep frequency-selective fading for the single-carrier frequency domain equalization. And the soft-modulated signal feeding back from the channel decoder will be used to obtain more accurate channel estimation. Then these estimated values will be available in the next iteration of equalization to achieve better equalization performance. So the equalizer and the channel estimator will build good relationship of improving performance between each other. The simulation results show that the joint algorithm exhibits superior performance in conditions of different channel in contrast to the iterative equalization algorithm only obtaining channel estimation from pilot sequence.