Computer Science – Information Theory
Scientific paper
2011-09-29
Computer Science
Information Theory
Scientific paper
Conventional MU-MIMO techniques, e.g. Linear Zero-Forced Beamforming (LZFB), require sufficiently accurate channel state information at the transmitter (CSIT) in order to realize spectral efficient transmission (degree of freedom gains). In practical settings, however, CSIT accuracy can be limited by a number of issues including CSI estimation, CSI feedback delay between user terminals to base stations, and the time/frequency coherence of the channel. The latter aspects of CSIT-feedback delay and channel-dynamics can lead to significant challenges in the deployment of efficient MU-MIMO systems. Recently it has been shown by Maddah-Ali and Tse (MAT) that degree of freedom gains can be realized by MU-MIMO even when the knowledge of CSIT is completely outdated. Specifically, outdated CSIT, albeit perfect CSIT, is known for transmissions only after they have taken place. This aspect of insensitivity to CSIT-feedback delay is of particular interest since it allows one to reconsider MU-MIMO design in dynamic channel conditions. Indeed, as we show, with appropriate scheduling, and even in the context of CSI estimation and feedback errors, the proposed MAT scheme can have performance advantages over conventional MU-MIMO in such scenarios.
Adhikary Ansuman
Caire Giuseppe
Papadopoulos Haralabos C.
Ramprashad Sean A.
No associations
LandOfFree
Multi-User MIMO with outdated CSI: Training, Feedback and Scheduling does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Multi-User MIMO with outdated CSI: Training, Feedback and Scheduling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-User MIMO with outdated CSI: Training, Feedback and Scheduling will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-150958