摘要
研究电子货架标签(ESL)的定位优化问题,为明确显示高温信息,可采用无线传感网络(WSN)的节点定位方法。因为室内环境中信号传播模型的遮蔽因子为一随机变量,在传统的WSN定位算法中,计算时通常略去上述因子,求出的估算距离与实际距离存在偏差,使得定位精度下降。针对上述问题提出改进方法。改进定位方法为一种循环执行的程序,每一次循环都会先进行粗定位,之后通过公式对遮蔽因子进行调整,最后在循环结束之后再进行一次精定位。仿真结果表明,在使用了提出的改进方法后,估计出了路径上的遮蔽因子,平均定位误差和累计误差概率都得到明显改善,可见,改进方法对提高定位精度有一定的作用。
In order to reduce the influence of continuous shadowing effect on positioning accuracy, a improved method based on the traditional method of existing was proposed for WSN node localization problem in indoor environ- ment which has many complex objects. Firstly, we mapped the filtered RSSI to distance by propagation model, then used maximum likelihood method to estimate the coordinates. Finally, we used the improved method to estimate shadowing factor so that to improve the accuracy of the final positioning. The simulation results show that the shado- wing factor in each path has been estimated by using the improved method based on maximum likelihood method pro- posed in this paper. The positioning accuracy is significantly improved.
出处
《计算机仿真》
CSCD
北大核心
2015年第8期311-314,共4页
Computer Simulation