Interplolation-based Maximum Likelihood Channel Estimation Using OFDM Pilot Symbols

Haiyun Tang, Kam Y. Lau, and Robert W. Brodersen
 GLOBECOM 02

An interpolation-based maximum likelihood channel estimation scheme using OFDM pilot symbols is proposed. Instead of direction estimation of the frequency response on each subchannel, an interpolation .lter is used on the pilot symbols to estimate a smaller set of coef.cients that are suf.cient to characterize the multipath channel. The actual frequency responses on the subchannels are then computed through inverse .ltering of these coef.cients. Because the same amount signal energy is used to estimated a reduced set of unknowns, the estimation accuracy is improved. The scheme is well suited for packet-based communication systems where pilot symbols instead of pilot tones are usually used at the beginning of packet for fast synchronization and channel estimation.