Kalman Filtering based Adaptive Frequency Domain Channel Estimation with Low Pilot Overhead for OFDM Systems

In this paper, we propose an adaptive frequency domain channel estimation method based on a modified Kalman filtering, which requires low pilot overhead, for estimating and tracking time-varying channel in orthogonal frequency division multiplexing (OFDM) systems. The proposed frequency domain Kalman filtering channel estimation achieves the minimum pilot overhead by exploiting periodically inserted pilot symbols and decision directed symbols between them. The pilot overhead efficiency and tracking performance of the proposed method is studied through simulation. Simulation results show that the proposed method has adequate tracking performance with a pilot overhead of below 5%.