Miniaturized 3-D Cross-Type Receiver for Wirelessly Powered Capsule Endoscopy
- 31 January 2019
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Microwave Theory and Techniques
- Vol. 67 (5) , 1985-1993
Abstract
This paper presents the modeling, implementation, and testing of a cross-type receiver (RX) used for wireless power transfer (WPT) into an endoscopic capsule. A 3-D configuration for the receiver is proposed to increase the wireless link power transfer efficiency (WL-PTE) and enhance its robustness to angular variations of the capsule. The diameter and thickness of the flexible transmitter coils are 200 mm and 185 μm, respectively. The diameter of the miniaturized RX is 8 mm, which is appropriate for integration within current commercially available capsules. Experimental results demonstrate a WL-PTE of 1.3% and complete system efficiency of 0.9% inside a suitable tissue phantom of the relative permittivity of 300 at 5 MHz. A maximum variation of only 8.4% of the WL-PTE across 90° orientation of the RX was also measured. The minimum WL-PTE of 1% is the recorder for 7-cm translational displacement inside the phantom. A simulated specific absorption rate of 0.86 W/Kg was calculated, which is well below the limit allowed for medical applications. A maximum temperature variation of 2.2 °C was also measured for an operating duration of 10 h, which is typical of a capsule journey inside the gastrointestinal tract. The proposed system represents a viable proposition for WPT in capsule endoscopy.Keywords
Funding Information
- Engineering and Physical Sciences Research Council (Programme Grant entitled Sonopill (EP/K034537/2))
- Heriot-Watt University through the Doctoral Training Programme for International Students
This publication has 44 references indexed in Scilit:
- New Analytical Model for the Characterisation of Printed Spiral Coils for Wireless Power Transfer2018
- High-efficiency CMOS rectifier with minimized leakage and threshold cancellation features for low power bio-implantsMicroelectronics Journal, 2017
- Optimization of planar strongly coupled wireless power transfer system for biomedical applicationsMicrowave and Optical Technology Letters, 2016
- A multi-coil inductive powering system for an endoscopic capsule with vibratory actuationSensors and Actuators A: Physical, 2011
- Efficiency optimization of wireless power transmission systems for active capsule endoscopesPhysiological Measurement, 2011
- A wireless power supply system for robotic capsular endoscopesSensors and Actuators A: Physical, 2010
- Study of a wireless power transmission system for an active capsule endoscopeThe International Journal of Medical Robotics and Computer Assisted Surgery, 2010
- The Future Is Wireless: Advances in Wireless Diagnostic and Therapeutic Technologies in GastroenterologyGastroenterology, 2009
- Efficient wireless non-radiative mid-range energy transferAnnals of Physics, 2008
- An inductive power link for a wireless endoscopeBiosensors and Bioelectronics, 2007