The Electromagnetic Compatibility Analysis Between FAST and the 2G-IMT System Around its RQZ

The coexistence of mobile communication and radio astronomy services in shared frequency bands significantly affects radio astronomy observation stability. To ensure an undisturbed electromagnetic environment in the five-hundred-meter aperture spherical radio telescope (FAST) radio quiet zone (RQZ), this article focuses on analyzing the electromagnetic compatibility (EMC) characteristics between FAST and second-generation international mobile telecommunications (2G-IMT) systems. Using the ITU-R P.2001 model validated by field experiments (with a root mean square error of 9.52 dB), the study examines the received power from the 2G-IMT base stations at FAST under different time probabilities, including different zenith angles, forward or back to the station antenna, and compares it with the protection threshold of FAST. Based on the results, it can be inferred that: in the study conditions, the received power of only one base station at FAST will not exceed the threshold. Thus, 99.99% of the 2G-IMT stations will generate electromagnetic interference to FAST. Furthermore, the proportion of analyzed data exceeding the FAST threshold is 65.49%. The aforementioned research results can provide a valuable reference for achieving EMC between FAST and other radio services around its RQZ. It additionally furnishes relevant analytical techniques and valuable recommendations for the assessment of electromagnetic radiation disruption in alternate radio telescope systems.