# Effective Mid-Range Wireless Power Transfer with Compensated Radiation Loss

**Authors:** N. Ha-Van, C. R. Simovski, F. S. Cuesta, P. Jayathurathnage, S. A. Tretyakov  
**arXiv:** [2302.02627](https://arxiv.org/abs/2302.02627)  
**Date:** 2023-02-06  
**Summary page:** https://www.summarizepaper.com/en/paper/2302.02627v1/

## Key points

- Conventional inductive wireless power devices transfer energy through reactive near fields
- Radiation from transmitting and receiving coils is often considered a parasitic effect that reduces power transfer efficiency
- Efficiency drops dramatically for larger distances, making conventional devices impractical
- This paper presents a dynamic theory of wireless power transfer between two small loop antennas
- The study aims to optimize mutual dynamic interactions between antennas to achieve efficient power transfer at large distances
- Analytical results have been validated through simulations and measurements
- The research offers a potential solution to greatly expand the range of distances for compact wireless power transfer devices
- Efficient power transfer can be achieved even at larger distances by leveraging radiation suppression due to optimized antenna interactions
- Implications include charging mobile telecommunication devices, electric vehicles, implantable medical devices, robots, wearable electronics, and energy harvesting systems
- The developed theory can be applied not only to different types of antennas but also to energy transfer between nano-objects
- This study contributes to advancing WPT technologies and opens up new possibilities for mid-range wireless power transfer with compensated radiation loss.

## Summary

In conventional inductive wireless power devices, energy is transferred through reactive near fields, similar to non-radiative F\"orster energy transfer in optics. However, the radiation from transmitting and receiving coils is often considered a parasitic effect that reduces power transfer efficiency. While conventional WPT devices can achieve high efficiency (around 80-90%) when the distance between antennas is small compared to their size, the efficiency dramatically drops for larger distances, rendering such devices impractical. To address this limitation, this paper presents a dynamic theory of wireless power transfer between two small loop antennas. The study aims to clarify the role of far-field radiation and explore the possibility of achieving efficient wireless power transfer at large distances by optimizing mutual dynamic interactions between transmitting and receiving antennas. The analytical results have been validated through simulations and measurements. The findings of this research offer a potential solution to greatly expand the range of distances for compact wireless power transfer devices. By leveraging the regime of radiation suppression due to optimized antenna interactions, it becomes possible to achieve efficient power transfer even at larger distances. This development has significant implications for various applications such as charging mobile telecommunication devices, electric vehicles, implantable medical devices, robots, wearable electronics and energy harvesting systems. Furthermore, the developed theory can be applied not only to coupling between antennas of different types but also to energy transfer between nano-objects. Overall, this study contributes to advancing WPT technologies and opens up new possibilities for effective mid-range wireless power transfer with compensated radiation loss.