Vol. 10, no.2, 2018


Alexander I. Zakharov, Lyudmila N. Zakharova, Alexander S. Nabatov, Viktor P. Sinilo, Mark V. Sorochinskii
Kotelnikov Institute of Radioengineering and Electronics of RAS, Fryazino Branch, http://fire.relarn.ru
Fryazino 141190, Moscow Region, Russian Federation
aizakhar@ire.rssi.ru, zakharova@ire.rssi.ru, nabatov@ire.rssi.ru, sinilo@ire.rssi.ru, sorochinskii@ire.rssi.ru

Received 10.09.2018
Abstract. In 2012, after a 20-year break, radar observations of the planets in Evpatoria were resumed with a use of upgraded planetary radar with RT-70 antenna. One of the features of radar operations in 2012 was a new scheme of correction the Doppler distortion of sounding signal. The correction was implemented in digital form after wide band registration of the echo signal. This correction was performed in a form of monotonous adjustment of signal sampling frequency in accordance with nonlinear law of two-way delay variations estimated from the model of the planet motion with respect to radar. The sequence of further signal processing stages included chirp heterodyning, filtering into a narrow frequency band with reduction of the signal sampling frequency, calculation and incoherent accumulation of power spectra. The technique of the spectra analysis in the range measurements procedure utilized precalculated reference radiophysical spectra of the signal scattered by the planet. Measurements of the distance to Venus near the interior conjunction were made, and 3.8 km discrepancy with a forecast was found. Because of too large distance to Mars (more than 180 million km), signal scattered by this planet was discovered only in one session with carrier signal. The results of radar observations confirm the operability of the RT-70 radar instrument in Evpatoria and ground-based signal processing software.

Keywords: radar astronomy, chirp signal, signal spectrum, planet orbit

UDC 621.396.967; 621.396.962

RENSIT, 2018, 10(2):167-174 DOI: 10.17725/rensit.2018.10.167

Full-text electronic version of this article - web site http://en.rensit.ru/vypuski/article/259/10(2)167-174e.pdf