Adaptive Subchannel Allocation for MC-CDMA System

Multicarrier code-division multiple-access is one of the effective techniques to gain its multiple access capability, robustness against fading, and to mitigate the ISI. In this paper, we propose an improved mulcarrier CDMA system with adaptive subchannel allocation. We analyzed the performance of our proposed system in frequency selective fading environment with narrowband interference existing and compared it with that of parallel transmission over many subchannels (namely, conventional MC-CDMA scheme) and DS-CDMA system. Simulation results show that adaptive subchannel allocation scheme, when used in conventional multicarrier CDMA system, the performance will be greatly improved.

Authors:

• Cuiran Li
• Jianli Xie
• Chengshu Li

Keywords:

• MC-CDMA
• Rayleigh fading
• Narrowbandinterference
• Channel estimation.

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