[1] Du Zhengfeng, Chen Jie, Pan Wen, Gao Xiqi, et al. EM-based detection schemefor differential unitary space-time modulation [J]. Journal of Southeast University (English Edition), 2007, 23 (4): 484-488. [doi:10.3969/j.issn.1003-7985.2007.04.002]

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EM-based detection schemefor differential unitary space-time modulation()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

23

Issue:

2007 4

Page:

484-488

Research Field:

Information and Communication Engineering

Publishing date:

2007-12-30

Info

Title:

EM-based detection schemefor differential unitary space-time modulation

Author(s):

Du Zhengfeng;  Chen Jie;  Pan Wen;  Gao Xiqi

National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China

Keywords:

unitary space-time modulation;  differential detection;  expectation maximization(EM)algorithm

PACS:

TN911.23

DOI:

10.3969/j.issn.1003-7985.2007.04.002

Abstract:

The performance loss of an approximately 3 dB signal-to-noise ratio is always paid with conventional differential detection compared to the related coherent detection.A new detection scheme consisting of two steps is proposed for the differential unitary space-time modulation(DUSTM)system.In the first step, the data sequence is estimated by conventional unitary space-time demodulation(DUSTD)and differentially encoded again to produce an initial estimate of the transmitted symbol stream.In the second step, the initial estimate of the symbol stream is utilized to initialize an expectation maximization(EM)-based iterative detector.In each iteration, the most recent detected symbol stream is employed to estimate the channel, which is then used to implement coherent sequence detection to refine the symbol stream.Simulation results show that the proposed detection scheme performs much better than the conventional DUSTD after several iterations.

References:

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Memo

Memo:

Biographies: Du Zhengfeng(1976—), male, graduate;Gao Xiqi(corresponding author), male, doctor, professor, xqgao@seu.edu.cn.

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