DocumentCode :
2655740
Title :
Iterative Biased MMSE Detections for DSTTD-OFDM Systems over Time-Varying Multipath Channels
Author :
Shin, Wooram ; Lee, Hoojin ; Seo, Changwoo ; Kang, Joonhyuk
Author_Institution :
Sch. of Eng., Inf. & Commun. Univ.
fYear :
2007
fDate :
22-25 April 2007
Firstpage :
1976
Lastpage :
1980
Abstract :
In this paper, we propose iterative biased minimum-mean-squared-error (BMMSE) detection schemes for double space-time transmit diversity (DSTTD)-orthogonal frequency division multiplexing (OFDM) systems over time-varying multipath channels. The time-varying effects cause intercarrier interference (ICI) and destroy the orthogonality of each STTD unit, considerably degrading system performance. To mitigate these impairments, we first estimate all transmitted symbols temporarily using sorted-QR-decomposition (SQRD)-based decision-feedback detection (DFD) considering the partial ICIs. Next, the significantly dominant ICI terms are eliminated with the help of the estimated symbols in the previous step. Finally, the SQRD-based DFD with the only desired subcarriers is performed. In each detection steps, we employ a biased MMSE criterion, which considers ICIs as well as noise. Numerical results demonstrate that the system performance of the proposed algorithms is greatly enhanced in comparison to the conventional schemes.
Keywords :
OFDM modulation; diversity reception; intercarrier interference; iterative methods; least mean squares methods; multipath channels; signal detection; space-time codes; time-varying channels; DSTTD-OFDM systems; decision-feedback detection; double space-time transmit diversity; intercarrier interference; iterative biased MMSE detections; iterative biased minimum-mean-squared-error detection schemes; orthogonal frequency division multiplexing; sorted-QR-decomposition; time-varying multipath channels; Design for disassembly; Fading; Interference; MIMO; Multipath channels; OFDM; Signal to noise ratio; System performance; Time varying systems; Wireless communication;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Vehicular Technology Conference, 2007. VTC2007-Spring. IEEE 65th
Conference_Location :
Dublin
ISSN :
1550-2252
Print_ISBN :
1-4244-0266-2
Type :
conf
DOI :
10.1109/VETECS.2007.409
Filename :
4212837
Link To Document :
بازگشت