GPS转发欺骗式干扰时延分析

在GPS转发欺骗式干扰中,转发时延是一项关键技术,当转发时延不合理时,会使接收机钟差改变,容易被识别,降低欺骗干扰的成功率。利用GPS伪距定位原理,推导了转发时延的算法,并针对不同的计算结果分析其对接收机钟差的影响。得出的结论为:当被转发卫星到转发器的距离与转发器到真实点距离之和不大于被转发卫星到虚拟点的距离时,干扰不会对接收机钟差产生影响，否则会影响接收机的钟差。从这个角度出发,对GPS转发欺骗式干扰源的部署位置做了分析，当转发器位于被转发卫星和真实点的连线上,可以使不对接收机钟差产生影响的虚拟点的选择范围最大。

Analysis of Time-delay in GPS Repeater Deception Jamming

In GPS repeater deception jamming, time-delay is a key technique, when time-delay is illogical, receiver''s clock off-sets will be changed, deception jamming can be identified easily and the success rate of the deception jamming will be reduced. The theory of GPS Pseudo-range is used in this paper to derive the time-delay algorithm and analyze the effect of different calculation results on receiver''s clock off-sets. The conclusion is obtained as that when the distance between transmitted satellite and jammer plus the distance between jammer and the real locus is no more than the distance between transmitted satellite and fictitious locus, jamming has no effect on receiver''s clock off-sets, otherwise it has an effect on receiver''s clock off-sets. From this point of view, the deployment location of jammer is analyzed: while the jammer is situated on the line formed by satellite and real locus, the selection scope of fictitious locus with no effect on receiver''s clock off-sets is the largest.