Performance enhancement of multiuser MIMO wireless communication systems

Kai Kit Wong, Ross D. Murch, Khaled Ben Letaief

Research output: Contribution to journalArticle

98 Citations (Scopus)


This paper describes a new approach to the problem of enhancing the performance of a multiuser multiple-input-multiple-output (MIMO) system for communication from one base station to many mobile stations in both frequency-flat and frequency-selective fading channels. This problem arises in space-division multiplexing systems with multiple users where many independent signal streams can be transmitted in the same frequency and time slot through the exploitation of multiple antennas at both the base and mobile stations, Our new approach is based on maximizing a lower bound for the product of signal-to-interference plus noise ratio (SINR) of a multiuser MIMO system. This provides a closed-form (noniterative) solution for the antenna weights for all the users, under the constraint of fixed transmit power. Our solution is shown by simulation to have better performance than previously proposed iterative or noniterative solutions. In addition, our solution requires significantly reduced complexity over a gradient search-based method that directly optimizes the product SINgs while still maintaining similar performance. Our solution assumes channel state information is present at the base station or transmitter.

Original languageEnglish
Pages (from-to)1960-1970
Number of pages11
JournalIEEE Transactions on Communications
Issue number12
Publication statusPublished - 1 Dec 2002



  • Cochannel interference
  • Flat and frequency-selective fading channels
  • Intersymbol interference
  • Multiple-input-multiple-output (MIMO) capacity
  • Smart antennas
  • Wireless communication systems

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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