PROPAGATION PATH OF LOW-FREQUENCY SKY-WAVE SIGNALS

Abstract

The propagation path of the sky-wave signals are studied in detail and some problems and errors occurring in the relevant work in the past are analysed. In the consideration of the refraction effect of the atmosphere, the radio apparent range, the length of the propagation path of the low-frequency sky-wave, the launching angle and the incidence angle with their influence on the time delay and the field strength of the LF sky-wave signals are deduced and calculated. The predictions on the D-layer of ionosphere and the time delay and field strength of the LF sky-wave signals are studied and the results show that the difference between the predicted values and the measured values are within ±1.5μs and ±2.5 dB for the time delay and the field strength respectively and that the accuracy of the timing via LF sky-wave can be raised to ±1.2μs and ±2.8 μs st daytime and at night respectively.