Transmit beamforming with cooperative base stations

Boon Loong Ng*, Jamie S. Evans, Stephen V. Hanly, Defne Aktas

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference proceeding contributionpeer-review

31 Citations (Scopus)


We consider a cellular network where base stations can cooperate to determine the signals to be transmitted on the downlink. In such a scenario, it would be possible to use "macroscopic" transmit beamforming to improve system performance. The downlink beamformer of interest is generalised from some transmit beamformers that have been shown to meet various optimality criteria in the literature. The particular down-link beamformer structure enables us to recast our downlink beamforming problem as a virtual LMMSE estimation problem. Based on this virtual set up, we exploit the structure of the channel and develop distributed beamforming algorithms using local message passing between neighbouring base stations. Two algorithms are outlined, both of which are based on the Kalman smoothing framework. The first algorithm is a forward-backward algorithm that produces optimal performance, but it has the disadvantage of a delay that grows linearly with array size. The second algorithm, which is a limited extent algorithm, solves the delay problem by using only local information.

Original languageEnglish
Title of host publicationProceedings of the 2005 IEEE International Symposium on Information Theory
EditorsThushara Abhayapala, Leif Hanlen
Place of PublicationPiscataway, NJ
PublisherInstitute of Electrical and Electronics Engineers (IEEE)
Number of pages5
ISBN (Print)0780391519, 9780780391512
Publication statusPublished - Sep 2005
Externally publishedYes
Event2005 IEEE International Symposium on Information Theory, ISIT 05 - Adelaide, Australia
Duration: 4 Sep 20059 Sep 2005


Other2005 IEEE International Symposium on Information Theory, ISIT 05


Dive into the research topics of 'Transmit beamforming with cooperative base stations'. Together they form a unique fingerprint.

Cite this