Anantha Chandrakasan

Learn More
Wireless distributed microsensor systems will enable the reliable monitoring of a variety of environments for both civil and military applications. In this paper, we look at communication protocols, which can have significant impact on the overall energy dissipation of these networks. Based on our findings that the conventional protocols of direct(More)
Networking together hundreds or thousands of cheap microsensor nodes allows users to accurately monitor a remote environment by intelligently combining the data from the individual nodes. These networks require robust wireless communication protocols that are energy efficient and provide low latency. In this paper, we develop and analyze low-energy adaptive(More)
Bidirectional adaptive body bias (ABB) is used to compensate for die-to-die parameter variations by applying an optimum pMOS and nMOS body bias voltage to each die which maximizes the die frequency subject to a power constraint. Measurements on a 150-nm CMOS testchip which incorporates on-chip ABB, show that ABB reduces variation in die frequency by a(More)
The potential for collaborative, robust networks of microsensors has attracted a great deal of research attention. For the most part, this is due to the compelling applications that will be enabled once wireless microsensor networks are in place; location-sensing, environmental sensing, medical monitoring and similar applications are all gaining interest.(More)
In this paper, we ask a fundamental question concerning the limits of energy efficiency of sensor networks What is the upper bound on the lifetime of a sensor network that collects data from a specified region using a certain number of energy-constrained nodes? The answer to this question is valuable for two main reasons. First, it allows calibration of(More)
A key challenge in ad-hoc, data-gathering wireless sensor networks is achieving a lifetime of several years using nodes that carry merely hundreds of joules of stored energy. In this paper, we explore the fundamental limits of energy-efficient collaborative data-gathering by deriving upper bounds on the lifetime of increasingly sophisticated sensor networks.
A software energy estimation methodology is presented that avoids explicit characterization of instruction energy consumption and pre-dicts energy consumption to within 3% accuracy for a set of bench-mark programs evaluated on the StrongARM SA-1100 and Hitachi SH-4 microprocessors. The tool, JouleTrack, is available as an online resource and has various(More)
This paper examines energy minimization for circuits operating in the subthreshold region. Subthreshold operation is emerging as an energy-saving approach to many energy-constrained applications where processor speed is less important. In this paper, we solve equations for total energy to provide an analytical solution for the optimum DD and T to minimize(More)