Using side information to improved channel estimation for channels with fractionally-spaced medium rays

We present a technique to incorporate the knowledge of the transmit filter and the receive filter into the channel estimation process, when the spacing between the medium rays is shorter than the symbol duration. We use the EDGE (Enhanced Data rates for Global Evolution) air interface to evaluate the impact of this new channel estimation technique. For the EDGE air interface, we derive analytical expressions showing that the error in estimating the channel coefficients is reduced by incorporating side information in the estimation operation. Simulation results with the EDGE air interface (8PSK modulation) are presented, and these simulations show a 1 dB reduction in E_b/N₀ required to achieve 1% block error rate at coding rate of 0.76 (i.e. MCS-7 mode of EDGE)