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Optimal operating frequency in wireless power transmission for implantable devices
Ada S Y Poon1, Stephen O'Driscoll, Teresa H Meng
1Department of Electrical and Computer Engineering, University of Illinois, Urbana-Champaign, IL 61801 USA. poon@uiuc.edu
Summary
This study reveals optimal wireless power transfer for implantable devices is in the GHz range, not MHz. This allows for significantly smaller receive coils, enabling fully integrated devices.
Area of Science:
- Biomedical Engineering
- Electrical Engineering
- Wireless Power Transfer
Background:
- Existing wireless powering for implantable devices relies on MHz-range frequencies.
- Current analysis techniques are insufficient for characterizing power transfer efficiency across wide frequency bands.
Purpose of the Study:
- To investigate short-range wireless powering for implantable devices.
- To determine the optimal frequency range for efficient power transmission in biological media.
Main Methods:
- Theoretical analysis of power transfer efficiency.
- Experimental validation of frequency-dependent power transmission.
Main Results:
- Optimal power transmission in biological media occurs in the GHz range.
- Existing solutions focusing on MHz range are suboptimal.
- A 10^4 reduction in receive coil size is achievable at optimal frequencies.
Conclusions:
- GHz-range frequencies are superior for wireless power transfer to implants.
- Reduced coil size facilitates fully integrated implantable device designs.
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