RFI Detection and Identification at OVRO Using Pseudonymetry

Protecting radio astronomy observatories from unintended interference is critical as wireless transmissions increases near protected bands. While database-driven coordination frameworks and radio quiet zones exist, they cannot rapidly identify or suppress specific interfering transmitters, especially at low signal-to-noise ratio (SNR) levels. This paper presents the first over-the-air field demonstration of Pseudonymetry at the Owens Valley Radio Observatory (OVRO), illustrating cooperative spectrum sharing between heterogeneous wireless systems. In our experiment, a narrow-band secondary transmitter embeds a pseudonym watermark into its signal, while the wide-band radio telescope passively extracts the watermark from spectrogram data. Results show that interference can be reliably detected and the interfering device uniquely identified even at low SNR where conventional demodulation is infeasible. These findings validate that passive scientific receivers can participate in a lightweight feedback loop to trigger shutdown of harmful transmissions, demonstrating the potential of Pseudonymetry as a complementary enforcement tool for protecting radio astronomy environments.