Abstract: A method to decrease power consumption of a plurality of end devices in a wireless network system divides a round period into at least a first period and a second period, each of the periods having multiple time slots. The wireless network system is formed by an access point, a plurality of routers and a plurality of end devices, forming a two-layer tree network topology. The method comprises: a) wirelessly broadcasting one router beacon in each of the time slots of the first period from one of the routers to the router's end devices; b) determining if any end device fails to receive any router beacon transmitted from its parent node in the first period; and c) configuring the end device to sleep during the second period if it fails to receive any router beacon transmitted from its parent node in the first period.

Abstract: A wireless network system utilizing dual frequencies comprises an access point having a first communication module, wherein the first communication module transmits downlink data and receives uplink data wirelessly in a first frequency; a plurality of routers, each having a second communication module, wherein the second communication module receives the downlink data from the access point and transmits the uplink data to the access point wirelessly in the first frequency and transmits the downlink data and receives the uplink data wirelessly in a second frequency; and a plurality of end devices, each having a third communication module, wherein the third communication module receives the downlink data from one of the plurality of routers and transmits the uplink data to the same one of the plurality of routers wirelessly in the second frequency.