Range extension of inductive coupling communication using multi-stage resonance

In this paper, multi-stage resonance is used to extend communication range of inductive coupling. Multi-stage resonance system is first analyzed theoretically, and then experimentally measured to evaluate the effectiveness of range extension by inserting two additional resonance coils in between the original transmitter and receiver coils to form a multi-stage resonance. From measurement, when using coils with diameters 20 mm, 60 mm, 60 mm and 20 mm in series from transmitter to receiver, total communication distance could be extended up to 100 mm, which is 42% increase compared to communication distance achieved when using single-resonance setup. Comparing with the state-of-the-art inductive coupling communication systems, our results show 10 times higher (range/diameter) ratio.