Effects of Coaxial-Lateral and Coaxial-Angular Displacements on Link Efficiency of a Wirelessly Powered Optogenetic Implant: Design, Modeling, and Experimental Validation
Effects of Coaxial-Lateral and Coaxial-Angular Displacements on Link Efficiency of a Wirelessly Powered Optogenetic Implant: Design, Modeling, and Experimental Validation
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同轴横向和同轴角位移对无线供电光遗传学植入物链路效率的影响：设计、建模和实验验证
DOI：
10.1109/jerm.2019.2909391
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发表时间：
2019
影响因子：
--
通讯作者：
I. Mahbub
中科院分区：
文献类型：
--
作者：
D. Biswas;N. Tasneem;I. Mahbub
近年来，无线功率传输（WPT）系统作为向小型化植入式传感器输送功率的手段已经取得了巨大的发展。由于各种位移（同轴、横向和角度），发射器和接收器线圈之间的耦合较松，因此向植入物有效输送功率是一项挑战。耦合系数由于位移而显著恶化，从而降低了系统的总体功率传输效率。在本文中，我们提出了一个分析和建模的各种位移的效率和整体性能的小型化WPT系统设计的光遗传植入的影响。为了模拟人体头部内的组织介质，使用介电特性对皮肤、颅骨和灰质层进行理论建模，并使用Ansys高频结构模拟器（HFSS）软件开发模拟模型。传播损耗和链路效率被建模和仿真为各种位移组合的函数。为了验证理论和仿真模型，WPT系统的特点是在各种位移条件下使用鸡胸肉作为组织介质。测量结果也显示出良好的协议与仿真结果，从而提供估计的失调公差范围为给定的规格。所提出的WPT系统在各种最坏情况下的效率性能分析也为将来设计闭环无线功率输送调节方案提供了初步模型。
In recent years, the wireless power transfer (WPT) system has evolved tremendously as a means to deliver power to miniaturized implantable sensors. Efficiently delivering power to implants is a challenge due to the loose coupling between the transmitter and receiver coils because of the various displacements (coaxial, lateral, and angular). The coupling coefficient deteriorates significantly due to the displacements, thus decreasing the overall power transfer efficiency of the system. In this paper, we present an analysis and modeling of the effects of various displacements on the efficiency and the overall performance of a miniaturized WPT system designed for an optogenetic implant. To emulate the tissue media inside a human head, skin, skull, and gray matter layers are theoretically modeled using dielectric properties, and simulation models are developed using Ansys high-frequency structure simulator (HFSS) software. The propagation loss and the link efficiency are modeled and simulated as a function of various displacement combinations. To validate the theoretical and simulation models, the WPT system is characterized in various displacement conditions using chicken breast as the tissue media. The measurement results also show a good agreement with the simulation results, thus providing estimation for the misalignment tolerance range for given specifications. The efficiency performance analysis of the proposed WPT system for various worst-case scenarios also provides a preliminary model for designing a closed-loop wireless power delivery regulation scheme in the future.