DocumentCode :
1099182
Title :
Space-Frequency Precoding with Space-Tap Correlation Information at the Transmitter
Author :
Yoon, Eunchul ; Hansen, Jonas ; Paulraj, Arogyaswami
Volume :
55
Issue :
8
fYear :
2007
Firstpage :
1645
Lastpage :
1645
Abstract :
In closed loop methods for obtaining exact channel state information at the transmitter (CSI-Tx), the overhead associated with the feedback can be excessive for fast mobiles. Channel-statistics-based CSI-Tx requires a much smaller overhead, and is, therefore, attractive for use with fast mobiles. We study ways to exploit correlation-based CSI-Tx in a multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system. We focus on a channel environment in which spatial and tap correlation are present. We propose a channel model for the case such that spatial and tap correlation can be separated, and show that this case channel correlation decreases the ergodic capacity of a MIMO-OFDM system when no CSI-Tx is available. However, this decrease can be mitigated when correlation based CSI-Tx is exploited. We introduce an optimal precoding approach to maximize capacity with spatial- and tap-correlation-based CSI-Tx. We also propose a statistical waterfilling scheme, which leads to almost optimal capacity performance without requiring computationally intensive numerical optimization. Based on these approaches, the impact of spatial and tap correlation is investigated.
Keywords :
Channel state information; Diversity reception; Fading; Feedback loop; Information systems; Laboratories; MIMO; OFDM; State feedback; Transmitters;
fLanguage :
English
Journal_Title :
Communications, IEEE Transactions on
Publisher :
ieee
ISSN :
0090-6778
Type :
jour
DOI :
10.1109/TCOMM.2007.902514
Filename :
4291813
Link To Document :
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