Summary: | We propose a human-area networking technology that uses the surface of the human body as a data transmission path and uses near-field coupling TRXs. This technology aims to achieve a "touch and connect" form of communication and a new concept of "touch the world" by using a quasi-electrostatic field signal that propagates along the surface of the human body. This paper explains the principles underlying near-field coupling communication. Special attention has been paid to common-mode noise since our communication system is strongly susceptible to this. We designed and made a common-mode choke coil and a transformer to act as common-mode noise filters to suppress common-mode noise. Moreover, we describe how we evaluated the quality of communication using a phantom model with the same electrical properties as the human body and present the experimental results for the packet error rate (PER) as a function of the signal to noise ratio (SNR) both with the common-mode choke coil or the transformer and without them. Finally, we found that our system achieved a PER of less than 10-2 in general office rooms using raised floors, which corresponded to the quality of communication demanded by communication services in ordinary office spaces.
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