Low complexity channel estimation scheme for OFDM systems with the aid of dynamic pilots

This paper presents a low complexity channel estimation scheme for OFDM systems in multipath fading channels. The proposed scheme is designed based on the pilots, which are arranged at different locations for different OFDM symbols. In slow and moderate time-varying fading channels, the channel frequency response could be estimated accurately with simple linear interpolation. On the other hand, the number of embedded pilots is reduced using the proposed scheme. Ultimately, the channel frequency response of the current OFDM symbol is estimated from the current and neighboring pilots and no further calculation is required. The effects of the Doppler frequency on the proposed scheme are also considered in this paper. Computer simulations are conducted to evaluate the performance of the proposed scheme. It is shown that the performance of the proposed scheme is close to maximum likelihood (ML) algorithm in the time-varying fading channels