Timing Synchronization of ZigBee Sensor Network for Ecology Observation

Timing synchronization is essential in case where multiple sensor nodes with ultrasonic sensors are deployed on the same place. This is because the ultrasonic sensors should be powered at an appropriate timing so as to prevent ultrasonic interference. In this paper, we propose a new timing synchronization method for ZigBee sensor network for ecology observation. In this method, a sensor node has been configured as a ZigBee router in order to exchange time information among nodes in real-time. Moreover, by concentrating the processing load to the server, the amount of calculation at each node can be minimized and is unaffected by the increase in nodes. By using the proposal method, it is concluded that the time synchronization should be executed per every few minutes in order to detect moving objects by the ultrasonic sensors.