射电天文研究组知识库

VHF (Very High Frequency) band antennaarray will receive analog signal from universe for storage after digital samplingand adding time scale, and then do the interference analysis of differentsub-station digital signal. It requires the time-frequency system with highprecision and low drifting. This paper explains a time-frequency system of VHFband antenna, which can produce standard 10 MHz signal and clock signal neededby sampler, to ensure that two computers which sampling data has the samesystem time and the storage data has the accurate time scale, the system includestime comparison programme based on the GPS network timing two different samplingcontrol computers. Timing strategy uses a time comparison software which basedon the Labview graphical programming platform. This software captures thesystem time of two computers to analyze and determine the time deviation whenthe two computers occurs time offset, and then grant the GPS time of NTP serverto the two computers through local area network in this time deviation. Finalresults show that this method can automatically calibrate the system time ofthe computers in the LAN, Precision Can Reach 0.1 s Orless.