Title :
A modified MMSE-SD soft detector for coded MIMO-OFDM systems
Author :
Dai, Yongmei ; Yan, Zhiyuan
Author_Institution :
Dept. of Electr. & Comput. Eng., Lehigh Univ., Lehigh, PA
Abstract :
We propose a low-complexity soft detector for coded MIMO systems, which generates soft information by combining the hard-decision maximum likelihood (ML) estimate with the soft information generated by the minimum mean square error (MMSE) detector. The hard-decision ML estimate is produced by a modified MMSE based sphere decoder (MMSE-SD). The MMSE-SD is desired since it has lower average and worst-case computational complexity than the zero-forcing (ZF) based SD (ZF-SD) and can be used for arbitrary MIMO configurations. The proposed modification simplifies the implementation of the MMSE-SD, and it can be efficiently implemented by previously proposed complex ZF-SD architecture with minor modification. Our soft detector offers a low-complexity alternative when list based soft detectors are not affordable.
Keywords :
MIMO communication; OFDM modulation; computational complexity; error detection; least mean squares methods; maximum likelihood estimation; coded MIMO-OFDM systems; computational complexity; hard-decision maximum likelihood estimation; low-complexity soft detector; minimum mean square error detector; modified MMSE-SD soft detector; soft information; sphere decoder; Computational complexity; Computer architecture; Detectors; MIMO; Maximum likelihood decoding; Maximum likelihood detection; Maximum likelihood estimation; Mean square error methods; OFDM; Receiving antennas; MIMO; MMSE; OFDM; Sphere Decoder; ZF;
Conference_Titel :
Circuits and Systems, 2008. ISCAS 2008. IEEE International Symposium on
Conference_Location :
Seattle, WA
Print_ISBN :
978-1-4244-1683-7
Electronic_ISBN :
978-1-4244-1684-4
DOI :
10.1109/ISCAS.2008.4541417
