Abstract: Localization is very important for the application of Wireless Sensor Network（WSN），but now the accuracy and stability of localization is not good enough.Received Signal Strength Indicator（RSSI） can be used to measure the distance between nodes in WSN.In this paper，core is introduced into WSN，a core is a body with three sensor nodes or more who have the fixed location relationship with each other.Core can localize other core or single sensor node，and also can be localized by WSN.Through simulation，it is found using core can improve accuracy of localization effectively.

Key words: localization, Wireless Sensor Network（WSN）, core, Received Signal Strength Indicator（RSSI）

摘要： 定位在无线传感网络的应用中有非常重要的作用，但是目前定位技术的准确度不够理想，RSSI是一种能实际使用确定传感网络中节点间距离的技术。在无线传感网络中引进了核，核是一个拥有三个或更多有着固定位置关系传感节点的物体。核能定位其他核或节点，同时核也能被传感网络定位。通过模拟发现使用核能有效提高定位的准确度。

关键词: 定位, 无线传感网络, 核, 接受信号强度指示