Trade-off between feedback load for the channel state information and system performance in MIMO communications

Abstract

The performance of multiple-input multiple-output (MIMO) communication systems is greatly increased by having channel state information (CSI) at the transmitter. In systems with no channel reciprocity, a limited feedback link is used to send the CSI from the receiver to the transmitter. However, the resources for the feedback link come at the expense of resources from the communications link. This paper studies the trade-off between accurate feedback and system performance for systems using different feedback techniques. The optimum feedback load is computed for different transmission schemes including time-division duplex (TDD) and frequency-division duplexing (FDD). © 2010 Institute for Computer Sciences, Social Informatics and Telecommunications Engineering.