时间反演联合TOA测距的室内指纹定位技术

在室内指纹定位中,室内环境会影响以接收信号强度指标(Received Signal Strength Indicator, RSSI)或信道状态信息(Channel State Information, CSI)的指纹数据,使得采集指纹数据构建的数据库具有不稳定性和不可靠性的特点,从而影响定位准确率和精度。基于此,本文提出了时间反演(Time Reversal, TR)联合到达时间(Time Of Arrival, TOA)测距的指纹定位技术。首先在定位区域建立坐标系,离线阶段采集两个已知参考点至网格点的距离作为指纹构建数据库,以坐标距离作为指纹可以忽略环境对指纹数据的影响,进而提高定位准确率;其次,在线阶段通过TR技术的空时聚焦性联合TOA,测出距离作为新指纹,与距离指纹进行对比匹配,根据相似度得出目标点的位置坐标。最后通过仿真结果得出:本方案实现了6 m的室内定位,并且定位误差在0.44 m以内,对比传统指纹定位,减小了指纹数据复杂度,提高了系统的鲁棒性和定位精度。 

Indoor fingerprint positioning technology based on time reversal and TOA ranging

In indoor fingerprint positioning, RSSI or CSI as fingerprint data would be affected by the environment, which results the database constructed by fingerprint data is unstable and unreliability, thus affecting the positioning accuracy. This paper proposes a fingerprint positioning technology based on TR and TOA ranging. First, a coordinate system is established in the positioning area, and the distance from two known reference points to the grid point is collected in the offline phase as a fingerprint to build a database, using coordinate distance as fingerprint can ignore the influence of environmental fingerprint data and improve the accuracy of location; Second, the TR technology is used in the online phase, combined with TOA to estimate the distance from the reference point to the target point, then matching the fingerprints in database to get the location of the target point. Finally, the simulation results show that this scheme achieved a accuracy below 0.44 m within a 6m. Compared with traditional fingerprint positioning, the complexity is reduced and the positioning accuracy is improved.