基于射频指纹的室内定位算法有很多,现提出基于射频指纹的应用在煤矿巷道这种特有的环境特征的一种新的定位算法.根据无线信号的衰减特性,将距离接入点3m处的接收信号强度值设为阈值,若设备接收的信号强度值大于阈值则直接定位到此接入点处.若信号强度低于阈值,则根据射频指纹数据库数据得到估计位置.在煤矿中移动目标的速度一般小于10m/s,根据这一特征,算法中设定前后两次的定位位置不能超过10m;若超过10m,则取前一秒的定位位置与该秒采用数据库匹配得出的位置的中点.将这些特征应用到射频指纹定位算法中可以非常有效的减少环境对信号强度的影响.通过实验表明,该定位算法具有较高的定位精度.%There are many indoor location algorithms based on the fingerprinting. A new localization algorithm is proposed based on fingerprint application in coal mine roadway which has special environment characteristics. According to the characteristics of the wireless signal attenuation, we take the received signal strength 3 m far away from the access point as a threshold. If the received signal strength value of the equipment is more than threshold, the target is directly located at the access point. If RSS is less than the threshold, the estimated location is got from RSS database. In the coal mine, the speed of moving target is generally less than 10 m/s, and according to this characteristic, we set the distance less than 10 m between the first location and the second location. If the distance is more than 10 m,the second location is set to the middle point of two points. The two characteristics is applied to the Fingerprinting Algorithm and it can reduce the influence of environment to the signal strength effectively. Through the experiments, it shows that the location algorithm has higher precision.
展开▼
