Performance of space-division multiple-access system using preprocessing based on feedback of vector-quantized channel spatial information

摘要

In this paper, we report the performance of multi-user transmitter preprocessing assisted multiple-input multiple-output downlink (DL) communication, when the channel impulse responses (CIRs) required to formulate the preprocessing matrix are fed back to the base station (BS) via feedback channels that endure noise and fading. Specifically, in our work the CIRs are estimated at the mobile stations (MSs) and are then decomposed by singular value decomposition. The magnitudes and phases associated with the right-hand side unitary matrix of each of the MSs are then vector-quantized (VQ) and conveyed to the BS as channel spatial information. This spatial information is then used to conceive the preprocessing matrix. Our study shows that the symbol-error-rate and capacity achieved with the ideal feedback scenario is close to that attained with perfect spatial information assumption. Hence, we advocate that VQ-spatial information based preprocessing comprises an efficient technique to deal with the DL multi-user interference.