Multi-User Diversity vs. Accurate Channel State Information in MIMO Downlink Channels
Abstract
In a multiple transmit antenna, single antenna per receiver downlink channel with limited channel state feedback, we consider the following question: given a constraint on the total system-wide feedback load, is it preferable to get low-rate/coarse channel feedback from a large number of receivers or high-rate/high-quality feedback from a smaller number of receivers? Acquiring feedback from many receivers allows multi-user diversity to be exploited, while high-rate feedback allows for very precise selection of beamforming directions. We show that there is a strong preference for obtaining high-quality feedback, and that obtaining near-perfect channel information from as many receivers as possible provides a significantly larger sum rate than collecting a few feedback bits from a large number of users.
Cite
@article{arxiv.0907.1099,
title = {Multi-User Diversity vs. Accurate Channel State Information in MIMO Downlink Channels},
author = {Niranjay Ravindran and Nihar Jindal},
journal= {arXiv preprint arXiv:0907.1099},
year = {2016}
}
Comments
Submitted to IEEE Transactions on Communications, July 2009