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arXiv · 0705.0428

An OFDM-CDMA scheme for high data rate UWB applications

Emeric Guéguen·Matthieu Crussière·Jean-François Hélard
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Abstract

In this paper, we investigate a new waveform for UWB systems obtained by the combination of Orthogonal Frequency Division Multiplex (OFDM) and Code Division Multiple Access (CDMA). The proposed system, called Spread Spectrum - Multi-Carrier - Multiple Access (SS-MC-MA) turns out to be a judicious solution to combat frequency selectivity and narrowband interferers, and to manage the coexistence of several users and piconets. It is shown that the addition of a degree of freedom brought by the spreading component of SS-MC-MA allows to optimize jointly the assignment of the number of used codes and coding rates in order to make the system more robust. Through simulations, it is demonstrated that the new system can outperform Multi-Band OFDM Alliance (MBOA) for low data rates and is able to provide wider range of rates.

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Emeric Guéguen, Matthieu Crussière, Jean-François Hélard. 2007-05-03. An OFDM-CDMA scheme for high data rate UWB applications. https://arxiv.org/abs/0705.0428

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