基于空间变异理论的电子地图构建方法

为提高位置指纹法在离线采样阶段建立电子地图(radio-map)的工作效率,提出了一种基于空间变异理论的radio-map构建的方法.将信号强度采样分解为趋势项和随机项描述其空间连续性和变异性.通过信号传播衰减模型建立趋势项和收发距离间的函数关系,利用普通克里金算法对非采样位置信号强度随机项进行最优线性无偏估计.最终实现根据少量采样计算定位区域任意位置信号强度的点估计.实验结果表明,该方法对信号强度的估计精度好于距离反比加权算法,在降低构建radio-map工作量的同时保证了定位精度.

A method for radio-map construction based on the spatial variability theory

In order to improve the working efficiency of radio-map construction of the location fingerprint method in the offline sampling stage,a method for constructing the radio-map was proposed based on the spatial variability theory.The signal strength sample was decomposed into trend and stochastic components to reflect its continuity and variability in the space.After obtaining the trend component,the relationship between the trend component and the distance of transceivers was built by a signal propagation attenuation model.The signal strength of any un-sampled place in the positioning area was estimated by employing the ordinary kriging method to calculate the linear unbiased estimator of the stochastic component.Experimental results show that the proposed method produces better estimation accuracy of the signal strength than WDI.It can decrease the workload of radio-map construction and ensure the positioning precision at the same time.