The Institute of Applied Astronomy of the Russian Academy of Sciences and the Goldstone Deep Space Communications Complex regularly conduct intercontinental radar observations of near-Earth objects...

The new 13-meters radio telescope recently built at Svetloe observatory (Russia) required a backend device that could digitize wideband signals from the receiving system, process the signal appropriately, prepare and transmit the resulting signal to the recorder. The previously existing backends, also used at other radio telescopes of Quasar VLBI network, could not provide compatibility with VGOS (VLBI Global Observing System) requirements. We developed Multifunctional Digital Backend (MDBE) with superior performance, flexibility and functions to equip the new antenna and other radio telescopes of the network with the same backend compatible with both domestic and international systems. The MDBE contains up to 12 input channels with 2 GHz bandwidth, powerful and remotely configurable Field programmable gate arrays (FPGA) for digital signal processing, and optical transceivers with total throughput of 50 Gbps per channel. The digital downconverters implemented in FPGA can form sub channels with 0.5, 2, 4, 8, 16, and 32 MHz bandwidth freely tuned with 10 kHz step. In wideband mode a single channel with 512, 1024 or full 2048 MHz bandwidth can be recorded. The MDBE also supports single-dish applications, such as radiometric and spectrometric observations. The paper presents the results of hardware and firmware development of the system, and the experimental results received with the MDBE in Svetloe observatory.

Results of radar and photometric observations of the asteroid 2017 VR12 are presented. The observations were carried out during the asteroid’s close approach to the Earth in 2018 on March 5 with 32-m...

Since 2017, the Institute of Applied Astronomy of the Russian Academy of Sciences in cooperation with the National Astronomical Observatories of the Chinese Academy of Sciences has been conducting observations of the Chang’E-3 lander carrier wave signal. The paper presents the features of observation scheduling and results of data processing. High-precision phase radar measurements have been obtained with an instrumental error of 1–2 mm. The deviation of residuals in model calculations does not exceed ± 1 cm. The estimates of CE-3 lander position have been obtained with an accuracy of 0.5’’, 7.4 m and 3.2 m in celenocentric cylindrical longitude, Px and Py coordinates, respectively.