Energy Transfer Using Gradient Index Metamaterial

Boopalan Ganapathy,Subramaniam Chittur Krishnaswamy

doi:10.1155/2018/7946168

Abstract

The gradient refractive index structure in this paper is used to increase the quantum of energy transfer. This is done by improving the directive gain of the pyramidal horn antenna at a frequency of 10 GHz. A three-dimensional array of closed square rings is placed in front of the horn antenna aperture to form a gradient refractive index structure. This structure increases the directive gain by 1.6 dB as compared to that of the conventional horn antenna. The structure nearly doubles the wireless power transfer quantum between the transmitter and the receiver when placed at both ends. The increase in the directivity is achieved by converting the spherical wave emanating from the horn to a plane wave once it passes through the structure. This transformation is realized by the gradient refractive index structure being placed perpendicular to the direction of propagation. The gradient refractive index is constructed by changing the dimensions of a closed square ring placed in the unit cell of the array. The change in the refractive index gives rise to an improvement of the half power beam width and side lobe level compared to that of the normal horn. The design and simulation were done using CST Studio software.

Highlights

Wireless power transfer (WPT) efficiency depends on the distance between the source and the receiver
We have demonstrated a method to improve the directivity and other antenna parameters like the beam width and side lobe level by employing an engineered metamaterial structure whose unit cell is a closed square ring (CSR)
The gradient refractive index is achieved by changing the dimensions of the CSR

Summary

Introduction

Wireless power transfer (WPT) efficiency depends on the distance between the source and the receiver. In the far-field region, the range of WPT depends on one or more of the following parameters, namely, transmitter power, directive gain of the transmitting and receiving antennas, and receiver sensitivity. The array is brought close to the source and the receiver so that the space between them is clear This can be achieved by the introduction of an array of metamaterial with gradient refractive index at the aperture or inside the conventional horn [11, 12]. We propose a method to enhance the energy transfer by introducing a flat structure near the aperture of the pyramidal horn antenna at 10 GHz. As we know, the conventional horn is used in applications such as point-to-point communication where high directivity becomes an essential requirement.

Methods

Results

Conclusion