Closed-loop transmit diversity for FDD WCDMA systems

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

Abstract

Transmit diversity techniques provide attractive solutions for increasing downlink capacity in 3G systems within low-mobility environments. Open-loop and closed-loop transmit diversity modes with two transmit antennas have already been included into 3GPP WCDMA Release 4, and at the moment schemes exploiting a larger number of transmit antennas are being developed.

System capacity can be increased from that of open-loop modes if the transmitter is equipped with additional side information of the downlink channel. In an FDD system this means that the receiver has to provide the information through some feedback mechanism.

In this paper we give a general algorithm by which it is possible to design a large variety of different closed-loop schemes depending on the feedback capacity of the system. The quantization of the transmit weights can be reduced to an eigenvalue problem by using linear functions of order statistics of the underlying probability distribution. This provides a simple analytical tool for the design of feedback algorithms. Furthermore, we provide analytical results for the transmit weights in the case of single-path Rayleigh fading channels.

Original languageEnglish
Title of host publicationCONFERENCE RECORD OF THE THIRTY-FOURTH ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS & COMPUTERS
EditorsMB Matthews
PublisherIEEE
Pages111-115
Number of pages3
ISBN (Print)0-7803-6514-3
DOIs
Publication statusPublished - 2000
MoE publication typeA4 Article in a conference publication
EventAsilomar Conference on Signals, Systems & Computers - Pacific Grove, United States
Duration: 29 Oct 20001 Nov 2000
Conference number: 34

Publication series

NameCONFERENCE RECORD OF THE ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS AND COMPUTERS
PublisherIEEE
ISSN (Print)1058-6393

Conference

ConferenceAsilomar Conference on Signals, Systems & Computers
Abbreviated titleASILOMAR
CountryUnited States
CityPacific Grove
Period29/10/200001/11/2000

Keywords

  • PERFORMANCE

Cite this

Hämäläinen, J., & Wichman, R. (2000). Closed-loop transmit diversity for FDD WCDMA systems. In MB. Matthews (Ed.), CONFERENCE RECORD OF THE THIRTY-FOURTH ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS & COMPUTERS (pp. 111-115). (CONFERENCE RECORD OF THE ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS AND COMPUTERS). IEEE. https://doi.org/10.1109/ACSSC.2000.910927