Results 141 to 150 of about 5,452 (173)

Windowing for multicarrier CDMA systems

IEEE Transactions on Communications, 2009
The windows for achieving good multiple-access performance of multicarrier code-division multiple-access (MCCDMA) systems employing minimum mean-squared error receivers are studied. The mean-squared error (MSE) is used as the performance metric for the optimization.
null Shun-Te Tseng, J.S. Lehnert
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Multicarrier FH codes for multicarrier FH-CDMA wireless systems

IEEE Transactions on Communications, 2000
A multicarrier (multihopping) scheme for multilevel frequency-shift keying/frequency-hopping code-division multiple access (MFSK/FH-CDMA) systems is proposed. In order to improve the frequency diversity capability for the proposed multicarrier MFSK/FH-CDMA system, several hopping frequencies per time slot are employed and transmitted in parallel.
null Chi-Fu Hong, null Guu-Chang Yang
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MUI-free multicarrier CDMA

Proceedings of the 2008 International Conference on Advanced Infocomm Technology - ICAIT '08, 2008
A new multicarrier CDMA system is proposed and its complete immunity to multiuser interference in the presence of unknown multipath fading channel is shown analytically.
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Orthogonal Multicarrier LAS-CDMA System

2007 International Conference on Wireless Communications, Networking and Mobile Computing, 2007
Multicarrier technology can be integrated into LAS-CDMA system. Based on the non-orthogonal multicarrier LAS-CDMA system, the orthogonal LAS-CDMA system is introduced in this paper. As different subcarriers get the diversity gain but not the multiplexing gain, the performance is good enough for high bit rate transmission.
Qingrong Zhang, Hancheng Liao
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Multicarrier techniques for wideband CDMA

ISCE '97. Proceedings of 1997 IEEE International Symposium on Consumer Electronics (Cat. No.97TH8348), 2002
This paper examines the performance of the multicarrier technique employed in a W-CDMA system in a frequency selective Rayleigh fading channel without a RAKE receiver. It is found that the multicarrier technique is simpler than the technique used in the single carrier RAKE receiver while producing a comparable performance to that of the RAKE receiver.
null Jiang Yue, M.A. Do
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Rotated spreading sequences for broadband multicarrier-CDMA

2003 IEEE 58th Vehicular Technology Conference. VTC 2003-Fall (IEEE Cat. No.03CH37484), 2003
We present an extension of the pure Walsh-Hadamard spreading sequences for MC-CDMA. By rotating the phase of the modulated signal before spreading, the signal space is exploited more efficiently. After spreading, the Euclidean distance of each superposed constellation is distributed more favorably in the signal space than without rotating.
Raulefs, R., Dammann, A., Kaiser, St., Auer, G.   +3 more
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Group-orthogonal multi-carrier CDMA

MILCOM 2002. Proceedings, 2003
Code division multiple access (CDMA) over frequency-selective fading channels faces challenges in suppressing multiuser interference (MUI), but can also benefit from the channel-induced multipath diversity. On the other hand, uncoded orthogonal frequency division multiple access (OFDMA) is MUI-free by design, but faces challenges arising from the ...
X. Cai, S. Zhou, G.B. Giannakis
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Interleaving scheme for multicarrier CDMA system

Journal of Electronics (China), 2004
In MultiCarrier Code-Division Multiple-Access (MC-CDMA) system, the received signals scattered in the frequency domain are combined to get frequency diversity gain. However, the frequency diversity gain is limited because of correlation between subcarriers. A novel interleaving scheme for MC-CDMA system is proposed in this paper.
Feng Shi, Shixin Cheng
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Performance of multicarrier DS CDMA systems

IEEE Transactions on Communications, 1996
In this paper, we apply a multicarrier signaling technique to a direct-sequence CDMA system, where a data sequence multiplied by a spreading sequence modulates multiple carriers, rather than a single carrier. The receiver provides a correlator for each carrier, and the outputs of the correlators are combined with a maximal-ratio combiner.
S. Kondo, B. Milstein
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Multicarrier CDMA systems with transmit diversity

Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152), 2002
Transmit diversity was previously proposed to reduce the detrimental effects in fading channels. In this paper we apply the space-time block codes to multicarrier CDMA systems. Our emphasis is on designing receivers that can decode the space-time codes and suppress the multiple access interference.
null Xiaodong Cai, A.N. Akansu
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