Toward Performance Improvements of RAKE Receiver with Pilot Power Allocation and Lagrange Filtering

In this paper a novel channel estimation scheme is proposed for a RAKE receiver operating in a time varying multi-path channel. The approach is an extension of the well known linear interpolation channel estimator, which is based on interpolating the channel estimates from pilot symbol sequence. In this paper parallel pilot-symbol aided channel estimation is considered. The proposed technique manages to combine the obtained samples over one chip duration using a Lagrange interpolation filter, and thereby enhances the signal-to-noise ratio and improves the quality of channel estimates. We also investigate optimal power assignment for the pilot and data channels. Simulation results allowed us to pinpoint optimum pilot-to-data channel power ratio for the best bit error performance.