Electromagnetic radiation from human activities, known as man-made Radio Frequency Interference (RFI), adversely affects radio astronomy observations. In the vicinity of the Upgraded Giant Metrewave Radio Telescope (uGMRT) array, the sparking on power lines is the major cause of interference at observing frequencies less than 800 MHz. A real-time broadband RFI detection and filtering system is implemented as part of the uGMRT wideband signal processing backend to mitigate the effect of broadband RFI. Performance analysis techniques used for testing and commissioning the system for observations in the beamformer and correlator modes of the uGMRT are presented. The concept and implementation of recording simultaneous unfiltered and filtered data along with data analysis and interpretation is illustrated using an example. For the beamformer mode, spectrogram, single spectral channel, and its Fourier transform is used for performance analysis whereas, in the correlator mode, the cross-correlation function, closure phase, and visibilities from the simultaneously recorded unfiltered and filtered is carried out. These techniques are used for testing the performance of the broadband RFI filter and releasing it for uGMRT users.
Real-Time RFI Mitigation in SPOTLIGHT: A Two-Stage Approach for Transient Searches
National Centre for Radio Astrophysics (NCRA)（国家射电天文中心）；Indian Institute of Science Education and Research (IISER)（印度科学教育与研究学院）；Silesian University in Opava（奥帕瓦西里西亚大学）；Oxford e-Research Centre (OeRC), University of Oxford（牛津大学牛津电子研究中心）
An Attempt to Search for Unintended Electromagnetic Radiation from Starlink Satellites with the 21 Centimeter Array: Methodology and RFI Characterization
Guizhou Normal University（贵州师范大学）；Guizhou University（贵州大学）；Shanghai Astronomical Observatory, Chinese Academy of Sciences（中国科学院上海天文台）；University of Chinese Academy of Sciences（中国科学院大学）；ShanghaiTech University（上海科技大学）；National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）
