短波信道频率相对时延的实测分析

Measurements and analysis of Frequency Relative Time Delay(FRTD) on HF Channel

利用电离层斜向探测系统分别对三条短波路径进行了时延测试,在单模传播数据曲线拟合的基础上,计算了短波信道频率相对时延值,重点分析了电离层单模传播情况下频率相对时延与频率间隔、传播路径及工作频率的变化特征。分析表明短波跳频系统在单模工作时,中午时段的频率相对时延最大,跳频频点间隔越小、路径越大频率相对时延的影响越小。

This paper presents the results of HF channel time delay measurements on 580 km, 940 km and 1 380 km paths using oblique ionospheric sounder equipment, and gives a curve fitting data processing methods to deal with measurements data of single mode. The variety characteristics of single mode FRTD is discussed on the basis of analysis of calculating results, it indicates that the FRTD values decrease with frequency interval getting small and paths distance increasing, the maximum FRTD value in a day appears at noon.