Results 151 to 160 of about 4,823 (179)

Receiver design in multicarrier DS CDMA communications

1999 IEEE International Conference on Communications (Cat. No. 99CH36311), 2003
We consider the design of multiuser receivers for improving the performance of MC DS CDMA communications over fading channels. We present a class of spreading codes that reduces the dimension of MMSE receiver and ML receiver without any performance loss.
Hujun Yin, Hui Liu 0011
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Multicarrier CDMA with cross-system interference cancellation

2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733), 2004
In this paper, the performance of a MC-CDMA system with cross-system interference cancellation is evaluated in an overloaded environment. Simulation results predict that a MC-CDMA receiver with cross-system interference cancellation is able to detect and demodulate signals in a Rayleigh fading environment with a loading of two, where a conventional MC ...
Kari Karwedsky, Diane Mills, Michael Kotrlik, Jay Weitzen   +3 more
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A Review of Multicarrier CDMA

2002
Multicarrier code-division multiple access (MC-CDMA) first appeared in the literature in 1993. It combines conventional code-division multiple access (CDMA) and orthogonal frequency-division multiplexing (OFDM), and has several variants that depend on how this combination is done. Although there have been a significant number of publications on MC-CDMA
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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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Multicarrier CDMA system with cochannel interference cancellation

Proceedings of IEEE Vehicular Technology Conference (VTC), 2002
In a conventional quasi-synchronous system, synchronized users, so-called in-sync users, experience less interference than do out of sync users. The authors propose a new technique to cancel the cochannel interference for an out-of-sync user in the forward link of a cellular CDMA system.
Shiro Kondo, Laurence B. Milstein
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Performance of downlink multicarrier CDMA with space diversity

Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137), 2002
We apply a simple transmit diversity technique to downlink multicarrier CDMA (MC-CDMA) systems. The resulting diversity on each subcarrier improves orthogonality among users which is distorted by the subcarriers' multipath fading. Accordingly, the diversity suppresses multiuser interference.
Yingxue Li, Costas N. Georghiades, Garng M. Huang   +2 more
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Transmitter and receiver optimization in multicarrier CDMA systems

IEEE Transactions on Communications, 2000
We consider transmitter and receiver optimization in multicarrier code-division multiple-access (MC-CDMA) systems under Rayleigh fading channels. Receiver optimization is performed in a decentralized manner, while transmitter optimization can be performed through either centralized or decentralized control of the powers of different carriers.
Tat M. Lok, Tan F. Wong
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A repetitively coded multicarrier CDMA (RCMC-CDMA) transceiver for multiuser communications

2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733), 2004
This work proposes an approximately MAI-free OFDM transceiver, called the repetitively coded multicarrier CDMA (RCMC-CDMA), which uses the CDMA technique to separate different users so that every user can utilize the whole bandwidth and time slot simultaneously.
Shang-Ho Tsai, Yuan-Pei Lin, C.-C. Jay Kuo   +2 more
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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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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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