摘要
由于GNSS系统的脆弱性,Loran-C/BPL系统作为GNSS系统的备份研究,受到国内外的重视,但如何获取高精度的传播时延一直是制约长波系统实现高精度授时的瓶颈。本文从测量角度出发分析路径时延的空间变化和时间变化,着重利用实际测量数据分析路径时延的时间变化规律。结果表明信号传播路径相似、且传播路径上天气变化相似的条件下相距100km内的用户其接收信号的传播时延时间变化规律基本相同,这为长波差分授时奠定基础。
Because of the fragility of the GNSS system,The Loran-C/BPL system has been paid more and more attention at home and abroad,as the backup of the GNSS system. How to get the precise propagation delay is always the bottleneck restricting the realization of high precision timing service in the long wave system. In this paper,the temporal variations and spatial variations of propagation delay are analyzed and the temporal variation is analyzed in detail with the actual measurement data. The result show that the received signal propagation delay temporal variations is basically the same,under the condition that the signal propagation path is similar and the weather condition in the transmission path is similar,hundreds of kilometers away from the users,which provides evidence for the BPL long wave differential timing.
引文
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