Computer Science – Information Theory
Scientific paper
2010-12-18
IEEE Trans. on Signal Proc., vol. 59, no. 12, pp. 6112 - 6126, Dec. 2011
Computer Science
Information Theory
Scientific paper
Spatial interference avoidance is a simple and effective way of mitigating interference in multi-antenna wireless networks. The deployment of this technique requires channel-state information (CSI) feedback from each receiver to all interferers, resulting in substantial network overhead. To address this issue, this paper proposes the method of distributive control that intelligently allocates CSI bits over multiple feedback links and adapts feedback to channel dynamics. For symmetric channel distributions, it is optimal for each receiver to equally allocate the average sum-feedback rate for different feedback links, thereby decoupling their control. Using the criterion of minimum sum-interference power, the optimal feedback-control policy is shown using stochastic-optimization theory to exhibit opportunism. Specifically, a specific feedback link is turned on only when the corresponding transmit-CSI error is significant or interference-channel gain large, and the optimal number of feedback bits increases with this gain. For high mobility and considering the sphere-cap-quantized-CSI model, the optimal feedback-control policy is shown to perform water-filling in time, where the number of feedback bits increases logarithmically with the corresponding interference-channel gain. Furthermore, we consider asymmetric channel distributions with heterogeneous path losses and high mobility, and prove the existence of a unique optimal policy for jointly controlling multiple feedback links. Given the sphere-cap-quantized-CSI model, this policy is shown to perform water-filling over feedback links. Finally, simulation demonstrates that feedback-control yields significant throughput gains compared with the conventional differential-feedback method.
Huang Kaibin
Kim Dongku
Lau Vincent K. N.
No associations
LandOfFree
Stochastic Control of Event-Driven Feedback in Multi-Antenna Interference Channels 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 Stochastic Control of Event-Driven Feedback in Multi-Antenna Interference Channels, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stochastic Control of Event-Driven Feedback in Multi-Antenna Interference Channels will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-157003