Title: Low-Overhead Cooperative Beamforming Under Imperfect Quantized SNR of Source-to-Relay Links
Authors: Wu, Jwo-Yuh
Hu, Chung-Hsuan
Wang, Tsang-Yi
電機工程學系
Department of Electrical and Computer Engineering
Keywords: Cooperative communications;amplify and forward;relay;beamforming;overhead reduction;quantization
Issue Date: 2012
Abstract: We consider a cooperative beamforming system with the amplify-and-forward protocol. To reduce the signaling overhead, each relay quantizes the SNR of the source-to-relay (S-R) link into one bit, which is then transmitted through a binary symmetric channel (BSC) with a known crossover probability to the destination. Given the set of the error-corrupted one-bit messages received at the destination, the beamforming design criterion is the maximization of the expected receive SNR, averaged over the conditional bit-flipping distributions of BSCs. We derive an analytic expression for the considered SNR metric, which is a complicated function of the beamforming weights. To facilitate analysis, we further derive a tractable lower bound for the conditional average SNR. By conducting maximization with respect to this lower bound, a closed-form sub-optimal beamformer can be obtained as a solution to a generalized eigenvalue problem. Computer simulations are used to illustrate the performance of the proposed scheme.
URI: http://hdl.handle.net/11536/17021
ISBN: 978-1-4673-1071-0
ISSN: 1551-2282
Journal: 2012 IEEE 7TH SENSOR ARRAY AND MULTICHANNEL SIGNAL PROCESSING WORKSHOP (SAM)
Begin Page: 425
End Page: 428
Appears in Collections:Conferences Paper