| 摘要 |
FIELD: radio engineering, communication.SUBSTANCE: chirp radio signals are used to determine the mode structure of an ionospheric SW channel and fix the time scale of spaced apart points based on accurate time signals with accuracy of up to few milliseconds, and the ionosphere is probed in the entire linear frequency modulation range of the radio system (3-30 MHz). A coordinated program is used to switch to a radiation/reception mode at a sliding frequency at a rate of 100 kHz/s in a narrower frequency interval, i.e. a "sawtooth" mode with repetition period ?T=1 s, which can be called a synchronisation mode. Frequency flies in the transmission frequency interval and can vary on the coordinated program during measurement. At time tthe transmitter starts, the receiver at the other end of the radio link starts after the mismatch time of time scales of said transmitter and receiver. The mismatch time is corrected during multiple radiation cycles, during which the difference frequency is measured and correction is performed.EFFECT: enabling measurement of propagation time of SW radio signals.2 dwg |
