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arXiv · 1405.7720

Full-Duplex Systems Using Multi-Reconfigurable Antennas

Elsayed Ahmed·Ahmed M. Eltawil·Zhouyuan Li·Bedri A. Cetiner
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Abstract

Full-duplex systems are expected to achieve 100% rate improvement over half-duplex systems if the self-interference signal can be significantly mitigated. In this paper, we propose the first full-duplex system utilizing Multi-Reconfigurable Antenna (MRA) with ?90% rate improvement compared to half-duplex systems. MRA is a dynamically reconfigurable antenna structure, that is capable of changing its properties according to certain input configurations. A comprehensive experimental analysis is conducted to characterize the system performance in typical indoor environments. The experiments are performed using a fabricated MRA that has 4096 configurable radiation patterns. The achieved MRA-based passive self-interference suppression is investigated, with detailed analysis for the MRA training overhead. In addition, a heuristic-based approach is proposed to reduce the MRA training overhead. The results show that at 1% training overhead, a total of 95dB self-interference cancellation is achieved in typical indoor environments. The 95dB self-interference cancellation is experimentally shown to be sufficient for 90% full-duplex rate improvement compared to half-duplex systems.

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Elsayed Ahmed, Ahmed M. Eltawil, Zhouyuan Li, Bedri A. Cetiner. 2014-05-29. Full-Duplex Systems Using Multi-Reconfigurable Antennas. https://arxiv.org/abs/1405.7720

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