Pilot-assisted adaptive interpolation channel estimation for OFDM signal reception

Accurate channel estimation is necessary for coherent detection of the orthogonal frequency division multiplexing (OFDM) signals. This paper studies pilot-assisted adaptive interpolation channel estimation for different pilot arrangements: time-multiplexed pilot, frequency-multiplexed pilot and scattered pilot. Interpolation filter tap weights are adaptively updated according to changes of the propagation channels by using the normalized least mean square (NLMS) algorithm. The average bit error rate (BER) performance in a doubly (frequency and time)-selective Rayleigh fading channel is evaluated by computer simulation. It is confirmed that the scattered pilot with two-dimensional adaptive interpolation channel estimation provides overall a good BER performance, compared to the time (or frequency)-multiplexed pilot case with one-dimensional adaptive interpolation channel estimation.