关键词: 无线传感器网络, 定位, 扇区天线, 全向天线

Abstract: According to the structural characteristics of Wireless Sensor Network（WSN），a novel range-free and distributed positioning algorithm（PBSAO） is proposed based on anchor’s sectored antenna and sensor’s omnidirectional antenna.In PBSAO algorithm，the information about the different sectored communication regions of anchors is broadcasted to the neighbor sensors using the anchor’s sectored antenna and power control.Then the positions of sensors are extracted through computing the overlapping region of the information.In order to improve the coverage rate of positioning，the located sensors work as anchors and also broadcast positioning information to neighbor sensors using omnidirectional antenna.Results of simulation show that the positioning precision of LBSAO is superior to that of other typical positioning algorithm，as well as the scalability and robustness，which can meet the requirements of positioning in large-scale WSN.

Key words: Wireless Sensor Network（WSN）, positioning, sectored antenna, omnidirectional antenna