A Mobile Client Platform for Sensor Networks

Presented is the design, hardware implementation and evaluation of a mobile computing platform that is well suited for use as an interface to wireless sensor networks. The device incorporates an 802.15.4 radio interface common in contemporary sensor network platforms, a color 320×240 pixel low-power organic LED (OLED) graphical display, an input device, and computation resources. The system includes several sensors relevant to a mobile device in a sensor network — a digital compass, multiple temperature sensors, a humidity sensor, and a pressure sensor for altimeter or barometer applications. The system incorporates these facilities, along with a rechargeable 2000mAh lithium-polymer battery, all within a form-factor of 2.1"×4"×0.5". The platform contains many hardware facilities to support current and future research directions in wireless sensor networks and their interactions with mobile computing systems, including a low-power signal strength monitoring circuit independent of the system’s main radio, support for dynamic operating voltage setting, power gating of peripherals, and built-in power monitoring circuits for power consumption introspection.