Optimal selection of pilot positions for frequency domain pilot multiplexing channel estimation in SC-FDE systems

In this paper, we investigate the pilot position selection (PPS) problem in the frequency domain pilot multiplexing technique (FDPMT) for channel estimation of single-carrier block transmission with frequency domain equalization (SC-FDE). Unlike the widely accepted point of view that the conventional PPS technique is the optimal one, this paper for the first time questions this viewpoint and demonstrates the suboptimal property of the conventional PPS technique. To further improve the performance of the FDPMT, an optimal PPS technique is proposed based on the minimization of the average bit error rate (BER). Compared with the conventioanl PPS technique, the proposed PPS technique exhibits better performance with similar complexity.