End-to-End Design of Efficient Ultrasonic Power Links for Scaling Towards Submillimeter Implantable Receivers.
End-to-End Design of Efficient Ultrasonic Power Links for Scaling Towards Submillimeter Implantable Receivers.
复制标题
端到端设计的高效超声电源链路，用于扩展到亚毫米植入式接收器。
DOI：
10.1109/tbcas.2018.2871470
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发表时间：
2018-10
影响因子：
5.1
通讯作者：
Arbabian A
中科院分区：
文献类型：
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作者：
Chang TC;Weber MJ;Charthad J;Baltsavias S;Arbabian A
我们提出了一个分析框架，用于优化超声无线功率链路的效率，用于缩小到亚毫米尺寸的植入式设备。考虑了各种参数的关键设计见解和权衡，包括工作频率、传输深度、发射器的尺寸、小型化接收器的阻抗和孔径效率以及接收器与植入物上的功率恢复链之间的接口。分析了球形聚焦换能器作为超声波发射器的性能，研究了其局限性和权衡。提出了两种优化方法：“焦点峰值”法将换能器的焦点设置在目标深度，“全局最大值”法在离焦操作的情况下使效率全局最大化。的结果也进行了比较，相控阵列的实现。为了研究植入物的效率，使用由单晶压电材料PMN-PT制成的小型化接收器，因为它们在导出的最佳载波频率范围（~ 1 -2 MHz）内具有谐振。然后使用光遗传学刺激器作为示例平台提供实现与功率电子器件的有效接口的方法。通过仿真和测量验证了分析结果。最后，演示了使用半径为2 cm的球形发射器的示例超声波链接;在6-10 cm深度处使用亚毫米接收器获得1.93-0.23%的链接效率，用于光遗传学应用。
We present an analytical framework for optimizing the efficiency of ultrasonic wireless power links for implantable devices scaled down to sub-mm dimensions. Key design insights and tradeoffs are considered for various parameters including the operating frequency, the transmission depth, the size of the transmitter, the impedance and the aperture efficiency of the miniaturized receiver, and the interface between the receiver and the power recovery chain on the implant. The performance of spherically focused transducers as ultrasonic transmitters is analyzed to study the limits and the tradeoffs. Two optimization methods are presented: “Focal Peak” sets the focus of transducers at target depths, and “Global Maximum” maximizes the efficiency globally with off-focus operation. The results are also compared to phased array implementations. To investigate the efficiency of implants, miniaturized receivers made from single crystalline piezoelectric material, PMN-PT, are used as they have resonances in the derived optimal carrier frequency range (~ l-2 MHz). A methodology to achieve an efficient interface to the power electronics is then provided using an optogenetic stimulator as an example platform. The analytical results are verified through both simulations and measurements. Finally, an example ultrasonic link using a spherical transmitter with a radius of 2 cm is demonstrated; link efficiencies of 1.93–0.23% are obtained at 6–10 cm depths with sub-mm receivers for the optogenetic application.