Space-time equalizer for advanced 3GPP WCDMA mobile terminal: experimental results

The conventional RAKE receiver employed in CDMA systems cannot satisfy the desired demand when the propagation channel possesses a considerable number of paths and in the presence of serious inter-user and inter-symbol interferences. Adaptive equalizer structures with fast convergence properties have been considered in such a context. This paper discusses the details of the hardware implementation of a novel adaptive equalizer based on the QRD-RLS algorithm and compares its performance with a conventional RAKE receiver. In order to reduce the computational complexity, the CORDIC algorithm has been exploited and implemented using a FPGA. The experimental results of the laboratory testbed under different channel conditions are discussed in the paper.