In view of the problems of many anchor nodes are needed

low positioning precision and high positioning cost of the weighted centroid localization（ WSL） algorithm

a WCL algorithm needs more anchor nodes.An improved WCL algorithm

WCL triangle received signal strength indication（ RSSI） hop（ WCL-TRH） based on single mobile anchor node aided is proposed. A mobile anchor node moves along the fixed route in monitor area

and broadcasts data packet in specified position; according RSSI ratios received by unknown node and minimum hops

weights are determined

the coordinate position of an unknown node is estimated. The simulation results show that the improved algorithm effectively improves the precision of positioning and stability

at the same time

reduce the costs of positioning.