On the performance of the decorrelating and the conventional discrete time rake receivers with improved channel estimation

The paper investigates the performance of different implementations of the discrete time rake receiver (DTRR). The conventional DTRR (CDTRR) is a matched filter to a discrete time equivalent model of the global channel resulting from the convolution of the impulse responses of the shaping filter and the multipath channel. Since the CDTRR performance degrades because of channel estimation noise, we apply some methods to improve channel estimation quality. We also develop the optimal version of the DTRR called decorrelating discrete time rake receiver (DDTRR) by means of the Karhunen-Loeve (KL) orthogonal expansion. Simulation results of both the CDTRR and DDTRR are then compared in different contexts.