Pilot Based Channel Estimation in IEEE 802 16a OFDM System

Orthogonal Frequency Division Multiplexing(OFDM) is a kind of transmission techniques with high frequency efficiency, which will be widely used in next-generation wireless communication systems. In this paper, pilot-based channel estimation for IEEE 802.16a OFDM system is studied. By comparing the performance of LS(least squares) estimator and Linear Minimum Mean-Square Error(LMMSE) estimator using Preamble 1 and Preamble 2 suggested by IEEE 802.16a standard in slow fading channel, we propose that Preamble 1 can be used in small multipath delay spread channel and Preamble 2 can be used in large multipath delay spread channel. Considering the tradeoff between performance and complexity, the LS estimator is suggested.