CAREER: Internet Connectivity for the Next Billion Devices

人们对物联网的兴趣越来越大--在物联网中，小型计算设备嵌入到日常物品和环境中。一个关键问题是，当这些设备变得更小、更多时，如何为它们供电；电池增加了体积、成本，并且需要充电，这在大规模情况下是困难的。这个项目建议设计一种无电池的设备，可以使用我们周围的WiFi网络连接到互联网。这项拟议中的研究预计将在WiFi行业创造一个务实的转变，在这个行业中，路由器除了提供到Wi-Fi设备的连接外，现在还可以利用射频供电的设备生态系统。传统的低功率Wi-Fi收发器需要比无线信号提供的更多电力，这使得射频供电的设备不可能真正使用WiFi协议。这项拟议的研究将产生算法、设计、电路和系统实现，使射频供电的设备和现成的Wi-Fi设备之间能够建立第一条通信链路，而不需要使用Wi-Fi。该项目将开发一系列技术，从新的低功耗模拟代码到Wi-Fi速率适配算法，以推动我们的通信范围和速率的限制。该项目还将设计一个完整的网络堆栈，使多个此类设备能够共存，并在这些无电池设备上开发全双工功能，以显著提高由此产生的链路层和网络层协议的功率效率。如果成功，该项目将创造射频供电的物联网愿景中的关键组件：将数十亿射频供电的设备连接到现有互联网基础设施的能力。

There is increasing interest in the Internet-­of­ Things where small computing devices are embedded in everyday objects and environments. A key issue is how to power these devices as they become smaller and numerous; batteries add bulk, cost, and require recharging that is difficult at large scale. This project proposes to design battery-free devices that can connect to the Internet using the WiFi networks around us. This proposed research is expected to create a pragmatic shift in the WiFi industry where in addition to providing connectivity to Wi­Fi device, routers can now tap into the RF­ powered device ecosystem.Conventional low-­power Wi­Fi transceivers require much more power than is available from wireless signals, making it infeasible for RF-­powered devices to literally speak the WiFi protocol. The proposed research will produce algorithms, designs, circuits, and system implementations that will enable the first communication link between RF-powered devices and off the-shelf Wi­Fi devices, without the need to speak Wi­Fi. This project will develop a range of techniques from new low-­power analog codes to Wi­Fi rate adaptation algorithms to push the limits on our communication range and rate. The project will also design a complete network stack that enables multiple such devices to co-­exist and develop full-duplex capabilities on these battery-­free devices to significantly improve the power efficiencies of the resulting link-­ and network-­layer protocols. If successful, this project would create the critical component in the vision of RF-­powered Internet of things: an ability to connect billions of RF-­powered devices to existing Internet infrastructure.