基于多源融合的OFDM室内定位技术研究

Research on OFDM Indoor Positioning Technology Based on Multi-source Fusion

目前各种室内定位技术都有其自身的优势和局限性,单一的定位技术已经无法满足高精度的室内定位需求。针对该问题,提出了一种基于多源融合技术的室内定位方法。利用常见正交频分复用(Orthogonal Frequency Division Multiplexing, OFDM)信号的时频二维特性实现测距定位,并通过识别主径的方式来抑制多径对子载波相位的影响,同时采用行人航位推算技术得到预测的用户位置,使用粒子滤波器将OFDM定位结果和行人预测信息进行滤波融合。实验结果表明,相较于单一的定位方法,融合后的定位方法更能满足室内定位需求,其平均定位误差小于1 m的概率大于95%。

At present,all kinds of indoor positioning technology have their own advantages and limitations,a single positioning technology cannot meet the high precision indoor positioning requirements.To solve this problem,an indoor positioning method based on multi-source fusion technology is proposed.The time-frequency two-dimensional characteristics of common Orthogonal Frequency Division Multiplexing(OFDM)signals are used to achieve ranging and positioning,and the influence of multipath on the subcarrier phase is restrained by identifying the main path.At the same time,the predicted user position is obtained by using the pedestrian dead reckoning technology,and then the OFDM positioning results and pedestrian prediction information are filtered and fused by using particle filter.The experimental results show that compared with the single positioning method,the fusion positioning method can better meet the indoor positioning requirements,and the probability of its average positioning error less than 1 m is greater than 95%.