CAREER: Bio-Adaptive Wireless Power Transfer and Signal Acquisition for Implantable Medical Devices

植入式医疗设备（IMDs）可以极大地帮助管理健康和预防疾病。解剖学上的限制限制了imd的尺寸，而且由于需要大量电池或感应供电天线，许多应用都是不可行的。提出的工作旨在提高无线功率传输效率，降低imd的功耗，从而增加可实现的植入深度和减小器件尺寸。两项主要创新将提高电力传输效率：(1)电磁IMD位置估计和(2)定向电力传输。IMD的位置将通过从外部天线阵列的后向散射信号的变化中提取空间信息来估计。提出了利用放大器单侧性和差分天线恢复后向散射信号的方法；调查需要多少天线来估计IMD的位置；并设计出有效的算法来进行位置估计。本文提出了将功率引导到中间场的IMD的电路和算法，该电路和算法最近被证明是为广泛类别的IMD供电的最佳场制度。在IMD应用中，功耗通常由信号采集主导。两个信号采集电路将实现更低的IMD功耗：(1)生物信号自适应放大器和(2)模拟数字转换器（ADC）架构，在中等分辨率下降低功耗。到目前为止，信息无损功率自适应仅在运动神经元传感应用的adc中得到证明。提出了将该方法推广到放大器和更广泛应用类别的电路和算法。连续近似ADC中的电容失配将通过可重构电容阵列减少，从而导致ADC面积和功率的大幅降低。此外，提出了一种基于时延二叉搜索的低功耗ADC架构。更广泛的影响该项目的主要影响将是在更大的植入深度上实现更小的imd，从而实现更广泛的新型imd，如亚毫米植入药物输送装置和分布式神经传感器，这将对医疗保健产生非常积极的影响。IMD的位置和方向估计可以更好地解释感测数据。所提出的ADC架构将在许多电子产品中非常有用，无论何时需要中等分辨率低功耗ADC。研究结果将发表在主要期刊上。该建议的一个主要部分是STEM外展计划，以扩大O？德里斯科尔?这是加州以前的K-12推广活动，获得了加州立法机构的书面表彰。

Intellectual Merit Implantable medical devices (IMDs) can greatly assist in managing health and preventing disease. Anatomical constraints limit the size of IMDs and many applications are infeasible due to the large required batteries or inductive powering antennas. The proposed work seeks to improve wireless power transfer efficiency and reduce power consumption in IMDs thereby increasing achievable implant depth and decreasing device size. Two major innovations will allow improved power transfer efficiency: (1) Electromagnetic IMD Location Estimation and (2) Directed Power Transmission. The location of the IMD will be estimated by extracting spatial information from variations in the backscattered signal across an external antenna array. It is proposed to: recover that backscattered signal by exploiting amplifier unilateralism and differential antennas; investigate how many antennas are required to estimate the location of the IMD; and to devise efficient algorithms to perform that location estimation. Circuits and algorithms to direct power to an IMD in the intermediate field which has been shown recently to be the optimum field regime for powering a broad class of IMDs are proposed. Power consumption in IMD applications is often dominated by signal acquisition. Two signal acquisition circuit thrusts will enable lower IMD power consumption: (1) Bio Signal Adaptive Amplifier and (2) Analog to Digital Converter (ADC) Architectures for lower power at moderate resolutions. Thus far information lossless power adaptation has been demonstrated only for ADCs in motor neuron sensing applications. Circuits and algorithms to generalize the method to amplifiers and to broader classes of applications are proposed. Capacitor mismatch in a successive approximation ADC will be reduced through a reconfigurable capacitor array leading to a substantial decrease in ADC area and power. Additionally, a low power ADC architecture based on binary search of time delays is proposed.Broader Impacts The primary broader impact of this program will be to enable smaller IMDs at greater implant depths thus enabling a broad class of new IMDs such as sub-mm implanted drug delivery devices and distributed neurosensors which should have very positive impacts in health care. The IMD location and orientation estimate will allow better interpretation of sensed data. The proposed ADC architectures will be useful in much of electronics, whenever moderate resolution low power ADCs are required. The findings will be published in leading journals. A major part of this proposal is the STEM outreach plan to expand Prof O?Driscoll?s previous K-12 outreach, which has received written commendation from the California State Legislature.