US Patent 7636341 Beacon scheduling method in wireless sensor network system

A beacon scheduling method is provided which can efficiently avoid beacon collisions and prevent power consumption of the router due to the unnecessary beacon transmissions. The beacon scheduling method of a router in a network system including at least one coordinator which sends beacons in a cycle and at least one router, includes sending a message to the router; receiving a reply message from the router; and determining a beacon transmission time of the router to an inactive period when the inactive period is secured in a beacon cycle of the coordinator.