Ergodic and Outage Performance of Fading Broadcast Channels with 1-Bit Feedback

In this paper, the ergodic sum-rate and outage probability of a downlink single-antenna channel with K users are analyzed in the presence of Rayleigh flat fading, where limited channel state information (CSI) feedback is assumed. Specifically, only 1-bit feedback per fading block per user is available at the base station. We first study the ergodic sumrate of the 1-bit feedback scheme, and consider the impact of feedback delay on the system. A closed-form expression for the achievable ergodic sum-rate is presented as a function of the fading temporal correlation coefficient. It is proved that the sumrate scales as log log K, which is the same scaling law achieved by the optimal non-delayed full CSI feedback scheme. The sumrate degradation due to outdated CSI is also evaluated in the asymptotic regimes of either large K or low SNR. The outage performance of the 1-bit feedback scheme for both instantaneous and outdated feedback is then investigated. Expressions for the outage probabiliti...

• Type: Journal
• Year: 2010
• Where: CORR
• Authors: Bo Niu, Osvaldo Simeone, Oren Somekh, Alexander M. Haimovich
• Keywords: 1-bit Feedback, CORR 2010, Education, Feedback, Feedback Scheme