RFI mitigation techniques in radio astronomy

Radio Frequency Interference (RFI) is a growing concern for the highly sensitive radio receivers of ground based radio telescopes. RFI reduces the sensitivity of a radio telescope and produces artifacts in the observed data. Over the years, several techniques have been proposed and implemented for mitigating RFI, either by controlling and eliminating sources of RFI around the radio telescope or its removal at different locations in the receiver chain. This paper examines regulatory and management efforts as well as technological approaches employed in mitigating radio frequency interference in radio astronomy observations. Also, the techniques currently under development and those proposed for the upcoming wide bandwidth and highly sensitive radio telescopes are described.