Low-Latency Channel Estimation for OFDM System in Fast-Fading Multipath Environments

Although suffering from inter-carrier interference (ICI), the proposed method can accomplish the channel estimation for the orthogonal frequency division multiplexing (OFDM) systems in high-mobility wireless communication environments using the conventional equally-separated stand-alone pilot arrangements. Initially, rough channel estimation based on the pilots is used for decoding the multiple low-density parity-check (LDPC) codes in each OFDM symbol in the first iteration. Correct decoding results provide reliable decision feedback, and can be used to form pseudo pilots and be combined with the original pilots to enhance the channel estimation in the following iterations. Simulation results confirm that the proposed method can extend the applicability of the OFDM systems equipped with the conventional pilot arrangement in fast-fading channels.