Time synchronization method for wireless sensor networks

The invention provides a wireless sensor network time synchronization method which comprises the following steps that (1) after a central node is initialized, standard source second pulse time information received from standard source equipment is broadcast to terminal nodes in the whole network; after the terminal nodes are initialized, the standard source second pulse time information is received; then steps (2) and (3) are respectively executed to the central node and the terminal nodes; (2) the standard source second pulse of the central node predicts and self-calibrates so as to update the standard source pulse time, responds to the requests of the terminal nodes and broadcasts the updated standard source pulse time to the terminal nodes of the whole network; and (3) the terminal nodes self-wake up, predict and calibrate synchronously. According to the wireless sensor network time synchronization method, the vacant detection energy consumption of the terminal nodes can be effectively reduced, the time synchronization execution frequency of the terminal nodes is reduced, the sleeping time of the terminal nodes is increased, so that the synchronization precision is high, the interference of a user is not needed, good synchronization precision and energy-saving effect are realized, and the time synchronization requirements of the low power consumption and high precision of the wireless sensor network can be well met.