椭圆定位的测距算法

针对无线传感器网络定位中传统的三边测距算法，为了降低算法中每个已知节点均具有发射和接收信号能力而造成的高额成本，提出了已知节点单发射多接收的定位模型，并基于该模型提出了椭圆定位算法.该算法通过刻画未知节点距已知节点可能的椭圆运动轨迹，进而运用牛顿迭代法求解所构造的二次轨迹方程组，实现对未知节点的定位.同时，对定位可能出现的错误进行了概率分析，得出错误概率与锚点个数之间的函数关系.实验定位与传统算法相比降低了实验成本，证明了锚点的线性增加会使错误概率指数趋势减少的特征，最后针对该定位错误问题提出了合理的解决方案.

Ranging Algorithm Based on Ellipse Localization

The high cost of wireless sensor network localization in the traditional triangular locating algorithm is due to the fact that each known nodes have the ability to transmit and receive signals. To address the issue, a location model is proposed to treat the known nodes as single-emitter and multi-receiver. Based on the model an ellipse localization algorithm is formulated. Localization of unknown nodes is achieved by characterization of the possible elliptical trajectory of unknown nodes from known nodes. Probabilistic analysis is also performed on positioning error. A proof is presented to show that linear increase in the number of anchors corresponds to exponential decrease of the error probability. Finally, a reasonable solution is provided to solve the positioning error issue.