Targeted jamming incident blinds GPS and BeiDou in east China’s Nanjing

Powerful, targeted jamming caused a temporary blackout of satellite navigation systems, including GPS and BeiDou, in a major Chinese city on Wednesday, an industry association said on Friday.\nThe disruption affected users in Nanjing, a city of nearly 10 million people and capital of the eastern province of Jiangsu, between 4pm and 10pm on Wednesday. Car navigation, food delivery, ride-hailing, and drone control apps relying on satellite positioning experienced a “systemic anomaly” during the period.\nUsers reported severe position drifting and total loss of road data, affecting daily life and the economy. The disruption paralysed location-dependent services, causing ride-hailing orders to plummet by 60 per cent and delivery efficiency to drop by 40 per cent, while bike-sharing systems reported location errors of up to 57km (35 miles), according to local media.\nThe incident was caused by “temporary interference and suppression” of global navigation satellite system (GNSS) signals, rather than mobile network failures, according to a technical analysis by the Nanjing Satellite Application Industry Association.\n“The interference specifically targeted the civilian frequency bands of both BeiDou and GPS, preventing receivers from correctly identifying positioning signals,” the association said on social media.\n“Consequently, effective navigation was impossible. Even devices equipped with offline maps suffered from location drift and a complete lack of data feedback due to the absence of a valid positioning source.”\n\n\nThe association did not mention who might have carried out the jamming, or for what purpose.\n“If this navigation disruption was caused by temporary signal control measures implemented for security during a major event, such actions are considered standard industry safety protocols,” it said, hinting at the possibility of a high-security event having taken place.\n“Relevant signals have already gradually returned to normal after the event concluded.”\nIt added that the signal anomaly had affected only civilian GNSS frequency bands and the BeiDou military frequencies had remained “completely unaffected” by the interference.\nBeiDou’s military and civilian frequencies are separated physically, and the military bands employ dedicated encryption and anti-jamming technologies to ensure reliable service for national defence and security, according to the association.\nIn contrast, the military and civilian signals of GPS share the same carrier frequencies, though they are functionally separated through distinct encryption and spectral modulation techniques.\nThe association said the fact that civilian BeiDou and GPS signals had been simultaneously disrupted in the incident was a “confirmation of farsighted strategic planning”.\nIt explained that in the event of a conflict between China and Nato – which relies on GPS operated by the US military – an attempt to jam BeiDou would also jam GPS, creating a strategic check and balance.\nIt noted that the decision to make BeiDou’s civilian frequency band compatible with GPS created a significant strategic deterrent: “Any deliberate interference targeting BeiDou’s civilian signals would simultaneously disrupt GPS-dependent applications, thereby fundamentally deterring malicious jamming and building a robust security barrier for China’s civilian navigation services.”\nSatellite jamming has been used in military conflicts, such as the Ukraine war, to sever communications and undermine precision. Iran has reportedly considered shifting to the BeiDou navigation system after experiencing GPS signal disruptions during its 12-day war with Israel and the US in June, which resulted in major losses at military and nuclear facilities.\n