Title
Receiver-coordinated distributed transmit nullforming with channel state uncertainty
Abstract
A distributed coherent transmission scheme in which two or more transmit nodes form a beam toward an intended receiver while directing nulls at a number of other “protected” receivers is considered. Unlike pure distributed beamforming, where the ith transmit coefficient depends only on the ith transmit node's channel to the intended receiver, the transmit coefficients of a distributed nullformer each depend on the channel responses from all of the transmit nodes to all of the protected nodes. The requirement for each transmit node to know all of the channels in the system makes distributed transmit nullforming challenging to implement in the presence of channel time variations. This paper describes a receiver-coordinated distributed transmission protocol, in the context of a state-space dynamic channel model, in which the receive nodes feed back periodic channel measurements to the transmit cluster. The transmit nodes use this feedback to generate optimal channel predictions and then calculate a time-varying transmit vector that minimizes the average total power at the protected receivers while satisfying an average power constraint at the intended receiver during distributed transmission. We demonstrate via analysis and numerical simulation the efficacy of the technique even with low channel measurement overhead, infrequent update intervals, and significant feedback latency.
Year
DOI
Venue
2012
10.1109/CISS.2012.6310822
Information Sciences and Systems
Keywords
Field
DocType
array signal processing,feedback,numerical analysis,protocols,radio receivers,radiotelemetry,time-varying channels,vectors,wireless channels,average total power minimization,channel response,channel state uncertainty,channel time variation,cluster transmission,distributed beamforming,distributed coherent transmission scheme,node channel transmission,nodes feed back periodic channel measurement,numerical simulation,optimal channel prediction,receiver-coordinated distributed transmission nullforming,receiver-coordinated distributed transmission protocol,state-space dynamic channel model,time-varying transmit vector
Beamforming,Channel models,Computer simulation,Computer science,Latency (engineering),Computer network,Communication channel,Transmission protocol,Periodic graph (geometry),Precoding
Conference
ISBN
Citations 
PageRank 
978-1-4673-3138-8
16
0.87
References 
Authors
8
4
Name
Order
Citations
PageRank
Donald Richard Brown1160.87
Upamanyu Madhow2504.27
Patrick Bidigare3160.87
Soura Dasgupta467996.96