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arXiv · 2408.15485

Software-defined Programmable Metamaterial Lens System for Dynamic Wireless Power Transfer Applications

Eistiak Ahamed·Rasool Keshavarz·Daniel Franklin·Negin Shariati
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Abstract

A software-defined 2-bit Programmable Transmit Metamaterial (PTM) array surface with beam steering capabilities is proposed for indoor dynamic Wireless Power Transfer (DWPT) applications. The novel metamaterial unit cell structure is designed based on transmission phase, amplitude, and electric field response to model DWPT using PTM. Theoretical analysis of the electric field (e-field), coupling effect, and current distribution at the metamaterial interface enhances the intelligence and reconfigurability of the PTM lens. The modeled 2-bit 6x6 array PTM is designed to operate at a frequency of 4 GHz. The reconfigurable architecture comprises a fixed system with a single-layer PTM lens capable of 60{\deg} beam scanning. The PTM lens, along with a distribution board, is fabricated and experimentally tested. The results between simulation and measurements are in good agreement. The system enables dynamic optimisation of the beam pattern to track the positions of mobile users with minimal software-hardware complexity. This novel work presents a low-cost experiment achieving an average 90.7% beamforming accuracy throughout the analytical and measurement processes of DWPT for movable users, utilizing a programmable transmit metamaterial array.

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Eistiak Ahamed, Rasool Keshavarz, Daniel Franklin, Negin Shariati. 2024-08-28. Software-defined Programmable Metamaterial Lens System for Dynamic Wireless Power Transfer Applications. https://arxiv.org/abs/2408.15485

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