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  • Research Article
  • Open Access

A Simple Differential Modulation Scheme for Quasi-Orthogonal Space-Time Block Codes with Partial Transmit Diversity

EURASIP Journal on Wireless Communications and Networking20072007:097475

  • Received: 21 August 2006
  • Accepted: 12 February 2007
  • Published:


We report a simple differential modulation scheme for quasi-orthogonal space-time block codes. A new class of quasi-orthogonal coding structures that can provide partial transmit diversity is presented for various numbers of transmit antennas. Differential encoding and decoding can be simplified for differential Alamouti-like codes by grouping the signals in the transmitted matrix and decoupling the detection of data symbols, respectively. The new scheme can achieve constant amplitude of transmitted signals, and avoid signal constellation expansion; in addition it has a linear signal detector with very low complexity. Simulation results show that these partial-diversity codes can provide very useful results at low SNR for current communication systems. Extension to more than four transmit antennas is also considered.


  • Information System
  • Communication System
  • System Application
  • Transmitted Signal
  • Signal Detector


Authors’ Affiliations

UniK, University of Oslo, P.O. Box 70, Kjeller, 2007, Norway
Department of Electronics, University of York, Heslington, York, YO10 5DD, UK


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© L. Song and A. G. Burr. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.