Multiuser Detection Using Blind Robust Beamforming in Multipath Environment for LTE System
Hassan M. A. Elkamchouchi, Darwish A. E. Mohamed, Osama G. Mohamed, Wael A. E. Ali · International Journal on Communications Antenna and Propagation (IRECAP) · 2016
This paper presents a new, efficient data detection for coherent signals in the uplink direction of Long Term Evolution (LTE) system for multiuser in multipath environment through adaptive processing of antenna arrays at the base station. The proposed algorithm at the receiver depends on a robust beamforming based Direction of Arrival (DOA) estimation to extract each path of coherent signals for each user separately, after that combining those estimated signals coherently for maximizing the received power and output signal to noise ratio. The proposed approach depends first on implementation of Re-iterative Superresolution (RISR) DOA algorithm. The RISR is applied here at the receiver for each sub-channel separately after the process of subcarrier demapping, that a signal is processed at each element of antenna array at the receiver. By applying this process the elements of antenna array are required to be only more than the number of received signals for each user (sub-channel), not more than the total signals. Multiple constrained minimum variance (MCMV) beamforming is then applied for purpose of paths extraction of each user exploiting the estimated signal's DOA, the extracted signals are combined coherently after time delay estimation and alignment of signals, finally the data is detected. The simulation results demonstrate the effectiveness of the proposed algorithm in multiuser multipath mobile environment with different modulation schemes.