Precoding for MIMO Systems in Line-Of-Sight (LOS) Environment
- 1 November 2007
- conference paper
- conference paper
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference
- p. 4370-4374
- https://doi.org/10.1109/glocom.2007.831
Abstract
In line-of-sight (LOS) environments, the signal detection of multiple-input multiple-output (MIMO) systems becomes difficult because the correlation among channels becomes higher when the phase differences of direct paths are close to each other. In this paper, we propose a MIMO system with precoding to maximize the minimum distance (denoted hereafter as Max-dmin precoding) to improve the performance of MIMO systems in LOS environments. Max-dmin precoding can improve the detection performance of maximum likelihood detection (MLD) by maximizing the minimum Euclidean distance between symbol points at the receiver side, but the design becomes complicated as the number of substreams increases. The design of our proposed Max-dmin precoding is easy by using the property that the first eigenvalue of channel matrix becomes dominant in LOS environments even when the number of substreams is large. We use long-term average channel state information (CSI) instead of instantaneous CSI for precoding. Moreover, we propose a reduced-complexity MLD that uses the ordered reliability of symbols that results from Max-dmin precoding. From the results of computer simulation, we show that our proposed scheme with reduced-complexity MLD can achieve low complexity and good bit error rate (BER) performance in LOS environments with Rician factor K = 5 dB.Keywords
This publication has 6 references indexed in Scilit:
- Design of Transmission Technique Utilizing Linear Combination Diversity in Consideration of LOS Environments in MIMO SystemsIEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, 2005
- Performance Analysis Based on Channel Matrix Eigenvalue for MIMO Systems in LOS EnvironmentsIEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, 2005
- Analysis of BER performances using channel matrix eigenvalue in MIMO systems under Rayleigh and Rician fading channelsPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2005
- Optimal Minimum Distance-Based Precoder for MIMO Spatial Multiplexing SystemsIEEE Transactions on Signal Processing, 2004
- Optimal designs for space-time linear precoders and decodersIEEE Transactions on Signal Processing, 2002
- Generalized linear precoder and decoder design for MIMO channels using the weighted MMSE criterionIEEE Transactions on Communications, 2001