Real-time station monitor and stationtest pipelines for LOFAR 2.0

Abstract: LOFAR is a low-frequency array distributed across several European countries. Each LOFAR station contains thousands of antennas and associated electronics, making monitoring and thorough testing of those components essential to ensuring station reliability. This paper discusses various anomalies that may arise in LOFAR antennas, tile elements, modems, and summators. We also introduce two diagnostic pipelines designed to detect these anomalies: a real-time station monitoring system and an offline stationtest system. These pipelines provide valuable insights into the operational status of each antenna, issuing alerts to minimize observational disruptions while maximizing station uptime, reliability, and sensitivity. By enhancing the efficiency and stability of LOFAR stations, they also serve as a foundation for future large-scale arrays like SKA-Low. The experience gained from their development and deployment will contribute to the construction and maintenance of SKA-Low, improving monitoring and diagnostic capabilities for large-scale antenna networks. Ultimately, these systems play a crucial role in ensuring continuous observations and maintaining data integrity.