Programmable Wireless Sensor Node Featuring Low-power FPGA and Microcontroller

A sensor node often uses a low-performance microcontroller unit (MCU) to reduce its power consumption. However, it is difficult to handle heavy tasks with the MCU. To solve this problem, we developed a new sensor node that uses an ultra-low power field-programmable gate array (FPGA) in addition to an MCU. By assigning heavy tasks, such as sensor and data processing, to the FPGA, we can avoid overloading the MCU. Both the configuration data for the FPGA and the programs running on the MCU can be injected from outside the sensor node using wireless communication. Thus, the functionality of the sensor node can be easily changed depending on the situation and/or the applications. In this paper, we describe the sensor node architecture and its prototype, and then we show the experimental results.