南京导航集体失灵，原因公布：本次干扰精准针对北斗、GPS民用频段

Core Viewpoint - The article discusses the navigation signal anomalies that occurred in Nanjing on December 17, 2025, emphasizing the technical reasons behind the issue and the strategic significance of the BeiDou and GPS systems' compatibility. Group 1: Navigation Signal Anomaly - The navigation failure was primarily due to temporary interference suppressing GNSS satellite signals (including BeiDou and GPS), rather than a network signal interruption, making offline maps ineffective [3][4]. - Offline maps only store geographic data and cannot replace the positioning signal source, as mobile navigation relies on GNSS signals from at least four satellites to calculate location coordinates [4]. Group 2: Strategic Significance of BeiDou and GPS Compatibility - The simultaneous impact on both BeiDou and GPS signals during the anomaly validates the strategic foresight of China's BeiDou system's civilian frequency planning [5][6]. - The compatibility of BeiDou's civilian signal (B1C frequency) with GPS's civilian signal (L1C frequency) allows for interoperability, creating a strategic balance where interference with BeiDou also affects GPS, thus deterring malicious disruptions [6]. Group 3: Military Frequency Resilience - The signal anomaly only affected civilian GNSS frequencies, while BeiDou's military frequency remained unaffected due to its separation from civilian frequencies [7]. - BeiDou's military system employs advanced anti-jamming technologies, ensuring robust resistance to interference and maintaining reliable time-space services for national defense and emergency support [7].