Navigational Disruption in Nanjing: Understanding the Incident
Summary:
- On December 17, 2025, a widespread navigational failure occurred in Nanjing affecting over one million users.
- Researchers determined the incident involved sophisticated jamming technology and was executed in two distinct phases.
- Future advancements aim to enhance real-time monitoring and protect against such disruptions.
On the evening of December 17, 2025, a significant navigational incident shook Nanjing, Jiangsu, as a large-scale disruption rendered mobile phone positioning systems ineffective. This event resulted in errant signal readings directing users towards Xuanwu Lake, unusual locking behaviors in shared bicycles, and illogical detours in online ride-hailing services.
Following the occurrence, the China Satellite Navigation and Positioning Association initiated a comprehensive analysis led by Academician Shi Chuang from Beihang University. The team leveraged the Beidou Navigation Public Service Platform, utilizing big data analytics to diagnose the nature and extent of the interference impacting navigational systems.
Jamming Technology: A Deceptive Attack
The first revelation in understanding this navigational failure lies in the type of interference employed: a sophisticated jamming technology that generates false signals closely mirroring the authentic signals of Global Navigation Satellite Systems (GNSS), including Beidou and GPS. This advanced manipulation tricks user terminals into interpreting these false signals as real, subsequently resulting in inaccurate positioning data.
Interference Process: Two Stages of Deception
The analysis outlined a structured interference process that unfolded in two distinct phases:
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Short-term Test Phase (15:11 – 15:15): Lasting just four minutes, the jamming originated in Jianye District and gradually expanded to surrounding areas such as Gulou and Xuanwu, affecting an estimated 50,000 users within a 120-square-kilometer radius. During this phase, the false positioning signals were low-speed, indicating an initial testing of interference effects.
- Long-term Disruption Phase (16:12 – 20:00): Coinciding with the evening peak travel hours, this phase lasted approximately 3 hours and 48 minutes. As interference signal power intensified, its reach broadened to encompass a staggering 750 square kilometers, affecting over one million users across Nanjing and its suburban locales. The complexity of the deception escalated, inducing positioning errors that misled mobile carriers into believing they were moving northeast.
Investigating the Source: Crucial Clues
Through diligent data analysis, several key clues emerged regarding the interference source:
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Origin and Trajectory: The analysis revealed that four distinct interference signal routes originated from Jianye District, propagating northeast. This method aimed to simulate drone flight patterns, thereby cloaking the deception’s origin and heightening the credibility of the jamming signals.
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Fixed Source of Interference: Despite the signals traveling a distance of ten kilometers, the area of affected users showed minimal displacement. This indicated that the actual source of the interference remained consistently hidden throughout the incident.
- Elevation Discrepancies: Intriguingly, the induced false locations typically presented an elevation of approximately 150 meters, while Jianye District’s average elevation is only between 4 to 10 meters. This stark contrast suggests that the interference source might be localized within a high-rise building, providing a potential lead for further investigations.
In response to this incident, future plans are being laid out to integrate 5G infrastructure with the Beidou Navigation Public Service Platform, coupled with advancements in big data and artificial intelligence. This confluence of technologies aims to bolster real-time monitoring capabilities for Beidou interference and establish precision in identifying the sources of such disruptions, fortifying national space-time information security against future threats.
The Nanjing navigational incident serves as a stark reminder of the vulnerabilities within our navigation systems and emphasizes the urgent need for enhanced monitoring and protection measures. As technology continues to evolve, proactive strategies must be prioritized to safeguard against increasingly sophisticated interference attempts, ensuring the reliability of navigation services for millions.
