A wireless energy link for endoscopy with end-fire helix emitter and Load-Adaptive power converter

This paper proposes a new Wireless-Powered Micro-Ball Endoscopy system, in which wireless power is emitted from an emitter array embedded in a floor and resonantly relayed by a passive wireless power jacket on patients. Comparing to other wireless powering endoscopy systems, both the patients' freedom of movement and the power efficiency are improved. To enhance the power efficiency, an End-Fire Helix Emitter is proposed, which is a fundamentally novel structure used for generating near field alternative magnetic field with high efficiency. This paper also proposes a Load-Adaptive power converter circuit to keep optimal power efficiency by matching the varied load impedance. A prototyping design is fabricated. At the frequency of 24.05MHz, the power efficiency of transmission from floor to wireless jacket is 44.6%, and the overall energy efficiency from floor to Endoscopic Micro-Ball is 2.5% at best.