[1] Wang Fang, Cheng Shixin, Chen Ming, Wang Haifeng, et al. Design and performance analysisof adaptive ordered LDPC coded OFDM system [J]. Journal of Southeast University (English Edition), 2007, 23 (1): 1-6. [doi:10.3969/j.issn.1003-7985.2007.01.001]

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Design and performance analysisof adaptive ordered LDPC coded OFDM system()

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

Volumn:

23

Issue:

2007 1

Page:

1-6

Research Field:

Information and Communication Engineering

Publishing date:

2007-03-30

Info

Title:

Design and performance analysisof adaptive ordered LDPC coded OFDM system

Author(s):

Wang Fang¹;  Cheng Shixin¹;  Chen Ming¹;  Wang Haifeng²

¹ National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China
²Nokia Technology Platform, Oulu 90570, Finland

Keywords:

low-density parity-check codes;  orthogonal frequency-division multiplexing;  ordering;  adaptive;  density evolution

PACS:

TN929.533

DOI:

10.3969/j.issn.1003-7985.2007.01.001

Abstract:

A novel adaptive ordered LDPC(low-density parity-check)coded OFDM(orthogonal frequency-division multiplexing)transmission technique is proposed to exploit different error probabilities of irregular LDPC coded bits in OFDM systems.Assuming that the CSI(channel state information)is known at the transmitter, the irregular LDPC coded bits are ordered according to their degrees and then allocated into subcarriers adaptively.Bits with higher degrees are allocated into less attenuated subcarriers and bits with lower degrees are allocated into deep attenuated subcarriers.Quantization on CSI feedback can be applied to minimize the signaling overhead.Performance of this strategy is analyzed by density evolution and numerical simulation.Simulation results show that about a 1 to 1.5 dB gain in terms of SNR(signal to noise ratio)can be achieved over frequency-selective fading channels compared to conventional LDPC coded OFDM systems without ordering, and the proposed scheme is robust to CSI quantization.

References:

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[11] Hu X Y, Eleftheriou E, Arnold D M.Regular and irregular progressive edge-growth Tanner graphs [J].IEEE Transactions on Information Theroy, 2005, 51(1):376-398.

Memo

Memo:

Biographies: Wang Fang(1978—), female, graduate, wangfangg@seu.edu.cn;Cheng Shixin(corresponding author), male, professor, sxcheng@seu.edu.cn.

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