Closed-loop quasi-orthogonal STBCs and their performance in multipath fading environments and when combined with turbo codes


Toker C., LAMBOTHARAN S., CHAMBERS J.

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, vol.3, no.6, pp.1890-1896, 2004 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 3 Issue: 6
  • Publication Date: 2004
  • Doi Number: 10.1109/twc.2004.827401
  • Journal Name: IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.1890-1896

Abstract

Quasi-orthogonal space-time block codes (QO-STBCs) achieve full code rate at the expense of loss in diversity gain. In this paper, we propose two feedback methods for QO-STBCs to achieve full diversity and full code rate. In the first method, signals radiated from various antennas are rotated by phasors according to feedback from the receiver, whereas the second method is based upon antenna weighting/selection. For high to moderate feedback error rates, it is demonstrated that the proposed methods outperform the quantized transmit beamformer. The performance improvement is also investigated for these closed-loop methods when the transmitted signal is error control coded.