Polyimide-Based Flexible Coupled-Coils Design and Load-Shift Keying Analysis

TL;DR

This paper presents a novel design of flexible polyimide-based coils for efficient wireless power transfer and data communication in implantable devices, analyzing the effects of coil mismatch and proposing solutions for robust data transmission.

Contribution

The paper introduces a flexible coil design on polyimide substrates and analyzes load shift keying for data transfer, addressing coil mismatch issues for implantable devices.

Findings

High power transfer efficiency achieved with the new coil design

Mismatched LC tanks reduce communication range and accuracy

Proposed solution improves robustness of data transmission

Abstract

Wireless power transfer using inductive coupling is commonly used for medical implantable devices. The design of the secondary coil on the implantable device is important as it will affect the power transfer efficiency, the size of the implant, and also the data transmission between the implant and the in-vitro controller. In this paper, we present a design of the secondary coil on a polyimide-based flexible substrate to achieve high power transfer efficiency. Load shift keying modulation is used for the data communication between the primary and secondary coils. A thorough analysis is done for the ideal and practical scenario and it shows that a mismatched secondary LC tank will affect the communication range and communication correctness. A solution to achieve robust data transmission is proposed and then verified by SPICE simulations.