High-precision measurement of satellite velocity using the EISCAT radar
- 1Department of Physics, University of Oulu, P.O. Box 3000, 90014, Finland
- 2EISCAT Scientific Association, Tähteläntie 54 B, 99600 Sodankylä, Finland
- 3Department of Physics, Faculty of Sciences, University "Dunărea de Jos" Galaţi, St. Domnească, No. 47, 800008 Galaţi, Romania
Abstract. This paper presents a method of measuring the velocity of a hard target using radar pulses reflected from the target flying through the radar beam. The method has two stages. First, the Doppler shifts of the echo pulses are calculated at a high accuracy with an algorithm which largely improves the accuracy given by the Fourier transform. The algorithm also calculates the standard deviations of the Doppler frequencies with Monte Carlo simulation. The second step is to fit the results from a sequence of radar pulses to a velocity model allowing linear variation of the second time derivative of target range. The achieved accuracies are demonstrated using radio pulses reflected by a satellite passing through the beam of the EISCAT UHF radar working at 930-MHz frequency. At high SNR levels, the standard deviations of the frequency from a single pulse reach typically down to 0.2 Hz. The best standard deviations of velocity fit are below 5 mm s−1 while those of the second time derivative of range are below 1 cm s−2.