Design of a Time Synchronization Mechanism Based on Doppler Effect for Underwater Wireless Sensor Networks
Wang Jian-pin · Chuangan jishu xuebao · 2014
Time synchronization is the fundamental problem of wireless sensor networks( WSN).Transmission fading of radio in underwater environment is extremely large,so it often uses ultrasound to transmit data in underwater wireless sensor networks( UWSNs).Due to the low transmission rate of ultrasound and moving of the sensor nodes in underwater environment,it will lead to serious signal transmission delay.In this paper,we design a time synchronization mechanism based on Doppler Effect for UWSNs.It can achieve time synchronization correction by detecting the received ultrasonic frequency variation. We test the performance of the synchronization mechanism by MATLAB. The experimental results show that,if the sampling time interval is shorter,the moving speed is faster and the depth of sensors in the water is smaller,the synchronicity will be higher.