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arXiv · 1907.11654

PhyCode: A Practical Wireless Communication System Exploiting Superimposed Signals

Wen Cui·Chen Liu·Lin Cai·Jianping Pan
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Abstract

Superimposed signals are anticipated to improve wireless spectrum efficiency to support the ever-growing IoT applications. Implementing the superimposed signal demands on ideally aligned signals in both the time and frequency domains. Prior work applied an average carrier-frequency offset compensation to the superimposed signal under the assumptions of homogeneous devices and static environments. However, this will cause a significant signal distortion in practice when heterogeneous IoT devices are involved in a dynamic environment. This paper presents PhyCode, which exploits the nature of varying offsets across devices, and designs a dynamic decoding scheme which can react to the exact offsets from different signal sources simultaneously. We implement PhyCode via a software-defined radio platform and demonstrate that PhyCode achieves a lower raw BER compared with the existing state-of-the-art method.

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Wen Cui, Chen Liu, Lin Cai, Jianping Pan. 2019-06-27. PhyCode: A Practical Wireless Communication System Exploiting Superimposed Signals. https://arxiv.org/abs/1907.11654

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