Design of a long range wireless 3-axis accelerometer module for environmental monitoring

3-axis accelerometer is a widely adopted device for applications such as fall detection of the elders, kinematic analysis, building/bridge/landslide monitoring, and so on. To retrieve the sensing data in real time, one may use a wireless module to forward those data to a gateway or server. For outdoor applications, Zigbee/IEEE 802.15.4 technology is often the candidate because it is cost effective and easy to be purchased in the market. However, transmission range, energy consumption and network capacity are key factors in designing an outdoor system. This paper presents the design of a long range wireless 3-axis accelerometer module which consists of a 14-bit 3-axis accelerometer, IEEE 802.15.4 SOC transceiver, high power RF front end, and switching regulator. Practical considerations are addressed in this paper.