Design Techniques for Remote Calibration of Passive Wireless Microsystems

无源无线微系统(PWMS)从射频电波中获取能量。没有笨重的电池使这些微系统的物理尺寸和成本降至最低，并消除了维护的需要。因此，PWMS可以植入产品或永久植入活体。由于体积小、无线接入、可编程、低成本和免维护操作，PWMS已经发现了广泛的新兴应用，包括植入式生物MEMS压力传感器、视网膜假体设备、眼压监测、胶囊内窥镜、用于无线动脉血流表征的压力传感器、用于人体和环境监测的温度传感器、pH传感器、物流自动化中的识别标签和产品认证等等。由于PWM受到工艺扩散、电源电压波动和温度变化(PVT)的影响，因此必须在预期运行之前对其进行校准。这些微系统的物理不可访问性要求它们的校准必须从基站无线进行，以下称为远程校准。该研究项目的长期目标是开发PWMS，用于医疗保健、产品认证和假冒、物体跟踪、评估管理、安全等领域的新兴应用，并将研究成果转化为加拿大工业的技术转移。该项目的短期目标是开发新的设计技术、电路拓扑和硅片实现，用于PWMS的远程校准，以确保它们的正常运行和与基站的可靠通信。该研究项目的目标是校准PWMS的以下关键模块：功率采集、系统时钟、模数转换器、电压和电流基准以及电压调节器。与电压模式或电流模式方法相比，时间模式方法具有很好的可伸缩性，并提供许多固有的优势，将在这些模块的设计和校准中得到充分探索和利用。这一研究项目针对的是对在新兴应用中部署PWMS至关重要的问题，特别是那些在物理上无法接触到PWMS的应用。由于将要开发的技术适用于一般的PWMS，因此这些发现将对科学界和工业界具有重要意义和兴趣。该项目还将为学生提供一个丰富的学习环境，让他们参与开发和设计具有大胆重点的应用程序的PWMS。

Passive wireless microsystems (PWMs) harvest their power from RF waves. The absence of bulky batteries minimizes the physical dimension and cost of these microsystems, and removes the need for maintenance. As a result, PWMs can be embedded in products or implanted in living bodies permanently. Attributive to small size, wireless accessibility, programmability, low cost, and maintenance-free operation, PWMs have found a broad range of emerging applications including implantable bio-MEMS pressure sensors, retinal prosthetic devices, intraocular pressure monitoring, capsule endoscopy, pressure sensors for wireless arterial flow characterization, temperature sensors for human body and environmental monitoring, pH sensors, identification tags in logistics automation, and product authentication, to name a few. Because PWMs are subject to the effect of process spread, supply voltage fluctuation, and temperature variation (PVT), they must be calibrated prior to their intended operation. The physical inaccessibility of these microsystems mandates that their calibration be conducted wirelessly from the base station hereafter referred to as remote calibration. The long-term objective of this research project is to develop PWMs for emerging applications in healthcare, product authentication and counterfeiting, object tracking, assess management, security, etc. and capitalizing research findings as technology transfer to Canadian industry. The short-term objective of this prject is to develop new design techniques, circuit topology, and silicon realization for the remote calibration of PWMs so as to ensure their proper operation and reliable communications with the base station. The research project targets the calibration of the following key blocks of PWMs: power harvest, system clocks, analog-to-digital converters, voltage and current references, and voltage regulators. Time-mode approaches that scale well with technology and offer many intrinsic advantages as compared with voltage-mode or current-mode approaches will be fully explored and utilized in both the design and calibration of these blocks. This research project targets issues that are critical to the deployment of PWMs in emerging applications especially those where PWMs are physically inaccessible. As the techniques to be developed are applicable to general PWMs, the findings will be of a great importance and interest to the scientific community and industries. The project will also provide a rich learning environment for students by engaging them in the development and design of PWMs with boldly focused applications.