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Content Provider | IEEE Xplore Digital Library |
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Author | Tadjpour, L. Shang-Ho Tsai Kuo, C.-C.J. |
Copyright Year | 1991 |
Abstract | A new multiuser orthogonal frequency division multiplexing (OFDM) transceiver with preceding, called the precoded multiuser OFDM (PMU-OFDM) system, was recently introduced by Tsai et al. (2005). The PMU-OFDM system can reduce multiaccess interference (MAI) due to the carrier frequency offset (CFO) to a negligible amount by preceding the data of each user with a codeword selected from either even or odd Hadamard-Walsh codes. The performance of the PMU-OFDM system in a mobile environment, where the channel response varies within one OFDM symbol due to the Doppler effect, is evaluated in this paper. It is shown by analysis and simulation that the use of even or odd Hadamard-Walsh codewords can greatly reduce the MAI effect due to the Doppler effect as well. Generally, all Hadamard-Walsh codewords except for the all-one codeword result in considerable suppression of intercarrier interference (ICI) induced by the Doppler effect. Furthermore, we discuss codeword priority schemes to minimize ICI as much as possible. Finally, simulations results are given to demonstrate the advantage of PMU-OFDM over OFDMA with a codeword priority scheme in the Doppler environment. We show that the PMU-OFDM system with odd Hadamard-Walsh codewords outperforms a half-loaded OFDMA system in a mobile environment. |
Sponsorship | IEEE Signal Processing Society |
Starting Page | 3787 |
Ending Page | 3799 |
Page Count | 13 |
File Size | 1385394 |
File Format | |
ISSN | 1053587X |
Volume Number | 55 |
Issue Number | 7 |
Language | English |
Publisher | Institute of Electrical and Electronics Engineers, Inc. (IEEE) |
Publisher Date | 2007-07-01 |
Publisher Place | U.S.A. |
Access Restriction | One Nation One Subscription (ONOS) |
Rights Holder | Institute of Electrical and Electronics Engineers, Inc. (IEEE) |
Subject Keyword | OFDM Time-varying channels Error correction Error correction codes Doppler effect Multiple access interference Transceivers Frequency division multiaccess Analytical models Interference suppression time varying Carrier frequency offset (CFO) fast fading multiaccess interference (MAI) multiuser orthogonal frequency division multiplexing (OFDM) precoding precoded multiuser OFDM (PMU-OFDM) |
Content Type | Text |
Resource Type | Article |
Subject | Signal Processing Electrical and Electronic Engineering |
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