Paolo Bruschi

Design Issues for Low Power Integrated Thermal Flow Sensors with Ultra-Wide Dynamic Range and Low Insertion Loss

Flow sensors are the key elements in most systems for monitoring and controlling fluid flows. With the introduction of MEMS thermal flow sensors, unprecedented performances, such as ultra wide measurement ranges, low power consumptions and extreme miniaturization, have been achieved, although several critical issues have still to be solved. In this work, a systematic approach to the design of integrated thermal flow sensors, with specification of resolution, dynamic range, power consumption and pressure insertion loss is proposed. All the critical components of the sensors, namely thermal microstructure, package and read-out interface are examined, showing their impact on the sensor performance and indicating effective optimization strategies. The proposed design procedures are supported by experiments performed using a recently developed test chip,including several different sensing structures and a flexible electronic interface.

Design of a wireless sensor network for urban pollution monitoring

Monitoring of air pollution is an essential clement for the management of urban areas, and today it is mostly implemented using fixed stations. In this work, we examine the design of an air pollution monitoring solution based on a wireless sensor network, and present some of the issues that must be confronted by the designer. The presented implementation is based on off-the-shelf networking hardware and custom developed sensors. The final system will include a porous silicon based NO2 sensor, a solid-state, low power anemometer, and temperature sensors. Specific attention is devoted, as is essential in a wireless sensor network, to power consumption issues. It will be shown the power requirements of the sensors often dwarf those of the network connectivity, so that smart sensor sampling strategies arc as important as communication strategies for proper power management.