Low-Power RF Integrated Circuits for Wireless Sensors Network Synchronization and Communicaation

Society has been witness to an on-going computing revolution as new classes of computing technology have displaced older technologies"”from mainframes decades ago to smartphones today. The rise of each new class of computing technology has brought about even smaller and more ubiquitous systems. As this trend continues, wireless sensor networks (WSNs) are widely perceived as the new frontier for a variety of applications, including infrastructure and health monitoring. Many applications, however, require sensor nodes with both long lifetimes and small volumes, resulting in highly energy-constrained systems. Of the tasks for a wireless sensor node, wireless synchronization and communication remain the highest energy.
This talk presents three RF integrated circuits designed to address these challenges. Two of the designs employ a new type of receiver called a clock-harvesting receiver. They each harvest a digital clock from an existing wireless standard, one from GSM and the other from CDMA, and can be duty-cycled to further conserve synchronization energy. Several other wireless standards also are investigated. The third design presented is a 10GHz UWB receiver for an energy-constrained cubic-mm node. The talk also will discuss system-level challenges such as battery limitations and clock accuracy that led to specific circuit design decisions.