# On the Achievable Diversity-Multiplexing Tradeoff in MIMO Fading Channels with Imperfect CSIT - Computer Science > Information Theory

On the Achievable Diversity-Multiplexing Tradeoff in MIMO Fading Channels with Imperfect CSIT - Computer Science > Information Theory - Download this document for free, or read online. Document in PDF available to download.

Abstract: In this paper, we analyze the fundamental tradeoff of diversity andmultiplexing in multi-input multi-output MIMO channels with imperfect channelstate information at the transmitter CSIT. We show that with imperfect CSIT,a higher diversity gain as well as a more efficient diversity-multiplexingtradeoff DMT can be achieved. In the case of multi-input single-outputMISO-single-input multi-output SIMO channels with K transmit-receiveantennas, one can achieve a diversity gain of dr=K1-r+K\alpha at spatialmultiplexing gain r, where \alpha is the CSIT quality defined in this paper.For general MIMO channels with M M>1 transmit and N N>1 receive antennas,we show that depending on the value of \alpha, different DMT can be derived andthe value of \alpha has a great impact on the achievable diversity, especiallyat high multiplexing gains. Specifically, when \alpha is above a certainthreshold, one can achieve a diversity gain of dr=MN1+MN\alpha-M+N-1r;otherwise, the achievable DMT is much lower and can be described as acollection of discontinuous line segments depending on M, N, r and \alpha. Ouranalysis reveals that imperfect CSIT significantly improves the achievablediversity gain while enjoying high spatial multiplexing gains.

Author: Xiao Juan Zhang, Yi Gong

Source: https://arxiv.org/