Research and realization of satellite radio frequency interference monitoring technology for FAST

Signals from artificial satellites are one of the main radio frequency interferences (RFI) in radio astronomical observations, which can bury astronomical signals and cause problems in searching and analyzing the signals. In order to mitigate the impact of satellites on astronomical observations, we have developed a satellite electromagnetic interference monitoring software for the Five-hundred-meter Aperture Spherical radio Telescope (FAST), which includes a satellite database, an observation module, and a monitoring module. In recent years, with the planning and launching of several giant satellite constellations and the increase in the number of telescope observation modes, the impact of satellites on radio astronomy observation has become more complicated, and the existing software can no longer meet the actual needs. Therefore, we have conducted research on key techniques in the monitoring of interference from individual satellites and constellations, and developed corresponding monitoring and analysis methods. Also, we have upgraded the existing software in many aspects, and the upgraded satellite database covers more in-orbit satellites and large constellations, and the observation module is able to support satellite transit prediction and interference estimation under more observation modes. In the actual observation, the calculation results of the software were verified by the spectrometer connected to the FAST receiver, which proved that the upgraded software can accurately predict the possible threatening satellites and the corresponding transit time in multiple observation modes, providing important support for the adjustment of the telescope observation planning, the avoidance of satellite interference, and the protection of the receiving system.