OPTIMIZED GAUSS AND CHOLESKY ALGORITHMS FOR USING THE LMMSE DECODER IN MIMO/BLAST SYSTEMS WITH FREQUENCY-SELECTIVE CHANNELS - Reduced-complexity Equalization

João Carlos Silva, Nuno Souto, Francisco Cercas, António Rodrigues, Rui Dinis, Sérgio Jesus

Abstract

The LMMSE (Linear Minimum Mean Square Error) algorithm is one of the best linear receivers for DS-CDMA (Direct Sequence-Code Division Multiple Access). However, for the case of MIMO/BLAST (Multiple Input, Multiple Output / Bell Laboratories Layered Space Time), the perceived complexity of the LMMSE receiver is taken as too big, and thus other types of receivers are employed, yielding worse results. In this paper, we investigate the complexity of the solution to the LMMSE and the Zero-Forcing (LMMSE without noise estimation) receiver’s equations. It will be shown that the equation can be solved with optimized Gauss or Cholesky algorithms. Some of those solutions are very computationally efficient and thus, allow for the usage of the LMMSE in fully-loaded MIMO systems.

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Paper Citation


in Harvard Style

Carlos Silva J., Souto N., Cercas F., Rodrigues A., Dinis R. and Jesus S. (2006). OPTIMIZED GAUSS AND CHOLESKY ALGORITHMS FOR USING THE LMMSE DECODER IN MIMO/BLAST SYSTEMS WITH FREQUENCY-SELECTIVE CHANNELS - Reduced-complexity Equalization . In Proceedings of the International Conference on Wireless Information Networks and Systems - Volume 1: WINSYS, (ICETE 2006) ISBN 978-972-8865-65-8, pages 200-208. DOI: 10.5220/0002087102000208


in Bibtex Style

@conference{winsys06,
author={João Carlos Silva and Nuno Souto and Francisco Cercas and António Rodrigues and Rui Dinis and Sérgio Jesus},
title={OPTIMIZED GAUSS AND CHOLESKY ALGORITHMS FOR USING THE LMMSE DECODER IN MIMO/BLAST SYSTEMS WITH FREQUENCY-SELECTIVE CHANNELS - Reduced-complexity Equalization},
booktitle={Proceedings of the International Conference on Wireless Information Networks and Systems - Volume 1: WINSYS, (ICETE 2006)},
year={2006},
pages={200-208},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0002087102000208},
isbn={978-972-8865-65-8},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Wireless Information Networks and Systems - Volume 1: WINSYS, (ICETE 2006)
TI - OPTIMIZED GAUSS AND CHOLESKY ALGORITHMS FOR USING THE LMMSE DECODER IN MIMO/BLAST SYSTEMS WITH FREQUENCY-SELECTIVE CHANNELS - Reduced-complexity Equalization
SN - 978-972-8865-65-8
AU - Carlos Silva J.
AU - Souto N.
AU - Cercas F.
AU - Rodrigues A.
AU - Dinis R.
AU - Jesus S.
PY - 2006
SP - 200
EP - 208
DO - 10.5220/0002087102000208