A++ Random Access for Two-way Relaying in Wireless Networks

Wenguang Mao; Xudong Wang

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arXiv · 1207.6174

A++ Random Access for Two-way Relaying in Wireless Networks

Wenguang Mao·Xudong Wang

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Abstract

Two-way relaying can significantly improve performance of next generation wireless networks. However, due to its dependence on multi-node cooperation and transmission coordination, applying this technique to a wireless network in an effective and scalable manner poses a challenging problem. To tackle this problem without relying on complicated scheduling or network optimization algorithms, we propose a scalable random access scheme that takes measures in both the physical layer and the medium access control layer. Specifically, we propose a two-way relaying technique that supports fully asynchronous transmission and is modulation-independent. It also assumes no priori knowledge of channel conditions. On the top of this new physical layer technique, a random access MAC protocol is designed to dynamically form two-way relaying cooperation in a wireless network. To evaluate the scalable random access scheme, both theoretical analysis and simulations are carried out. Performance results illustrate that our scheme has achieved the goal of scalable two-way relaying in a wireless network and significantly outperforms CSMA/CA protocol.

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Wenguang Mao, Xudong Wang. 2012-07-26. A++ Random Access for Two-way Relaying in Wireless Networks. https://arxiv.org/abs/1207.6174

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