Bruce, Nicholas2026-07-072026-07-072026https://hdl.handle.net/1828/24054This dissertation presents the design, implementation, and philosophy of an end-to-end radio frequency interference monitoring system designed primarily for radio astronomy observatories. Motivated by the growing density of anthropogenic emitters and the corresponding threat to ground-based radio astronomy, the work describes a modular monitoring pipeline that includes hardware, signal processing, and machine learning. This work introduces several novelties: a gain-stable wideband receiver providing calibrated long-term radio frequency environment comparisons, a direction-of-arrival estimation method allowing use of arbitrarily arranged antennas, a digital down-converter architecture enabling insight into individual signal detections, and an unsupervised learning framework to perform modulation recognition and novelty detection. The dissertation also emphasizes the importance of modular, software-defined architectures and outlines future work towards real-time algorithms for next-generation interference management.enAvailable to the World Wide Webradio frequency interferenceradio receiversoftware defined radiodigital signal processingmachine learningdirection-of-arrival estimationradio environmentradio astronomyAn end-to-end radio interference monitoring systemThesisN. Bruce, C. Baard, S. Harrison, M. Islam, A. J. Otto, D. Lagoy, R. Messing, B. Robert, T. Robishaw, and P. F. Driessen, “Wideband RFI monitor requirements, design, and commissioning at DRAO,” Publications of the Astronomical Society of the Pacific, vol. 138, p. 065005, June 2026.N. Bruce, J. Stacey, and P. F. Driessen, “Visibility domain direction-of-arrival optimization for arbitrary 2-D arrays,” IEEE Access, pp. 1–1, 2022N. Bruce, S. Harrison, and P. Driessen, “DDC Pool: Efficient down-conversion of signals for RFI monitoring,” in Proceedings for RFI 2022, 2022.N. Bruce, B. Moa, S. Harrison, and P. F. Driessen, “SigCLR: A contrastive learning approach to unsupervised modulation recognition and novelty detection,” in Proceedings of Radio Frequency Interference Conference — PoS(RFI2024), vol. 471, p. 025, 2025.