南京导航集体失灵，原因公布：GNSS卫星信号受到临时干扰压制，精准针对北斗、GPS民用频段，北斗军用频率不受影响

Core Viewpoint - The navigation signal anomaly in Nanjing on December 17, 2025, was caused by temporary interference affecting GNSS satellite signals, not by a network signal interruption [1][2]. Technical Analysis - Offline maps cannot resolve the navigation anomaly as they only store geographic data and do not replace the need for positioning signals [2][3] - Mobile navigation relies on GNSS satellite signals (at least 4 satellites) to calculate position coordinates, making positioning signals and map data independent systems [3] - The interference specifically targeted the civilian frequency bands of Beidou and GPS, leading to unrecognized positioning signals, resulting in navigation failures even with offline maps [3] Strategic Significance - The simultaneous impact on Beidou and GPS signals during the anomaly validates the strategic foresight of China's Beidou system in planning civilian frequency bands [4] - The international satellite navigation spectrum follows a "first come, first served" rule, with GPS having occupied core L-band resources early on, leaving limited quality spectrum for Beidou [4] - The compatibility of Beidou's civilian signal (B1C band) with GPS's civilian signal (L1C band) breaks the spectrum resource blockade and creates a strategic balance, where interference with Beidou also affects GPS applications [4] Military Frequency Resilience - The signal anomaly only affected civilian GNSS frequency bands, while Beidou's military frequencies remained unaffected [5] - Beidou employs a military-civilian frequency separation design, with military frequencies being exclusive and physically isolated from civilian bands [5] - The military system incorporates advanced anti-jamming technologies, ensuring robust resistance to interference and deception, thus maintaining reliable time-space services for national defense and emergency support [5] Context of the Anomaly - If the navigation anomaly was a result of temporary signal control measures for major event security, it falls within standard safety protocols, with signals gradually returning to normal post-event [6] - Reports indicated that multiple navigation software systems experienced failures, leading to delivery delays and operational issues for services like food delivery and bike-sharing [9][17]