Ultra Low Power Electronics for Autonomous Micro-Sensor Applications

Micro-sensors are remote detection system composed of one or more sensors, a data converter, a micro-controller equipped with memory, a transceiver for two way wireless communication, and a power source such as a battery. These small self contained micro-sensor systems can be used in a variety of applications. They can measure an environmental metric and report it to a base station. They can also communicate with each other. This could be useful in forming a wireless network in which information is communicated over a long distance by a relay of micro-sensors. If micro-sensors can be designed to consume significantly less power the variety of practical applications increases. They can be placed in more remote locations and require less frequent servicing for battery replacement. This proposal deals with significantly reducing the power consumption of the RF transceiver without compromising performance. The modeling of transistors in sub-threshold will be studied to correct model deficiencies and remove risk from RF sub-threshold design. A variety of new circuit topologies are introduced which are better suited for sub-threshold operation. Also, circuit topologies are introduced that save significant power through merging functions in a single transistor. The total of all the power saving innovations should lead to a significant power savings in the overall transceiver. BENEFIT: Next generation micro-sensor systems can, in part, be enabled by an ultra low power system, which would extend the usable life of a node. It would also enable the placement of nodes in a greater variety of locations since most of the size and weight of the electronics can be due to the battery. By employing ultra low power micro-sensors, the overall system will be substantially lower in cost, simpler to maintain, and more rugged (if using node redundancy) than present day sensor systems. In response to this challenge, Nu-Trek is proposing to substantially reduce the power dissipation of micro-sensor RF transceiver circuitry. Solving this problem is critical to the eventual goal of reducing the overall micro-sensor power by a factor of 10 since the transceiver circuitry is the most sensitive and power intensive circuitry in the micro-sensor system.