Radio frequency interference mitigation at the Westerbork Synthesis Radio Telescope: Algorithms, test observations, and system implementation

The sensitivity of radio astronomical stations is often limited by man-made radio frequency interference (RFI) due to a variety of terrestrial activities. An RFI mitigation subsystem (RFIMS) based on real-time digital signal-processing is proposed here for the Westerbork Synthesis Radio Telescope based on a powerful field programmable gate array processor. In this system the radio astronomy signals polluted by RFI are "cleaned'' with the RFIMS before routine back-end correlation processing takes place. The high temporal and frequency resolution of RFIMS allows the detection and excision of RFI better than do standard radio telescope back-end configurations.