GPS World

Tag: GPS spoofing circles

  • New GPS ‘circle spoofing’ moves ship locations thousands of miles

    New GPS ‘circle spoofing’ moves ship locations thousands of miles

    New research by Bjorn Bergman of the environmental non-profit SkyTruth has found ships in various parts of the world reporting locations thousands of miles away and circling at precisely 20 knots.

    Bergman’s findings were first reported at the annual meeting of the Resilient Navigation and Timing Foundation on May 5.

    Bergman previously observed and reported on circling phenomena with GPS-based reporting systems from vessels and fitness trackers in China ports. It has also been observed in Tehran, Iran. In all those cases, though, it was clear that the real location was fairly nearby the false and circling locations.

    In the most recent observations, the actual locations of the ships were thousands of miles away. In most cases, literally halfway across the globe.

    Image courtesy of Skytruth and RNTF.
    Image courtesy of Skytruth and RNTF.

    Bergman said that he was able to verify the vessels’ approximate true location by examining the field of view of the satellite receiving the automatic identification system (AIS) position reports. The satellites are only able to see an area about 5,000 kilometers wide.

    A satellite that could only see the Gulf of Guinea in West Africa, for example, received GPS-based location data from a ship’s AIS that showed the vessel offshore of Point Reyes in northern California. The vessels’ true locations were also confirmed by their position reporting before and after the “displacement events.”

    Bergman was unsure if these errors are the result of the ships’ AIS systems or some fault or influence on GPS navigation receivers. It is clear that ongoing “circling” incidents in China are some form of GPS interference.

    GPS-based fitness tracker reporting was affected the same way and at the same time as those of receivers on vessels. Bergman has been able to find no similar supporting data for these long-range displacement and circling events.

    While Bergman was able to observe these events, he was at a loss to explain them. In previously observed cases it seemed clear a disruption device was nearby and affecting a large number of vessels. In these incidents, each vessel was the only one in its vicinity affected, and the vessels were separated by thousands of miles.

    Image courtesy of Skytruth and RNTF.
    Image courtesy of Skytruth and RNTF.

    Further hampering analysis, and making even speculation difficult, was the lack of commonality among the few cases observed.

    The vessels were of much different types and operations. Pilot boats, work boats, tugs, cargo and passenger vessels were all involved.

    The length of these disruptions also varied greatly. The shortest recorded was a reefer ship for less than half an hour. A crew boat was “displaced” for more than 16 days.

    While most of the vessels reported circling positions off the coast of Northern California, two were displaced to Madrid, one to the vicinity of Hong Kong, and one to the Chinese city of Shanwei. One even began reporting it was circling a location offshore of northern California, and subsequently reported circling positions that drifted east almost a thousand miles inland to Utah.

    A true mystery, the RNT Foundation is hoping to crowdsource ideas and share them with Bergman and other analysts. Anyone with insights or ideas about this mystery is encouraged to send them to [email protected].

    A video of Bjorn Bergman’s presentation at the RNT Foundation’s annual meeting is available on the foundation’s website and below. He has also posted a short paper on these events on SkyTruth’s website.

  • Chinese GPS spoofing circles could hide Iran oil shipments

    Chinese GPS spoofing circles could hide Iran oil shipments

    “GPS spoofing circles” have been discovered at 20 locations along the Chinese coast, according to the non-profit environmental group Skytruth. Of the locations observed, 16 were oil terminals; the others were corporate and government offices.

    GPS spoofing in Shanghai that resulted in reported positions from ships, fitness trackers and other GPS enabled devices forming circles some distance from the shore was first observed by the non-profit C4ADS. Subsequently, Professor Todd Humphreys briefed the phenomena at an Institute of Navigation conference in September. The MIT Technology Review published an article about it in November.

    This caught the interest of an analyst at the environmental non-profit Skytruth.

    Evaluating a larger data set of ship AIS (Automatic Identification System) data, analyst Bjorn Bergman discovered at least 20 locations near the Chinese coast where similar spoofing had taken place in the last two years.

    Sixteen of these “spoofing circle” locations were oil terminals. The most frequent occurrences by far were at the port of Dalian in northern China, close to the border with North Korea. Based upon the timing of the spoofing, imposition of sanctions on purchase of Iranian oil by the United States, and observations by others of Iranian oil being received by China, Bergman suggests that much of the spoofing is designed to help conceal these transactions.

    Of the four locations not associated with oil terminals, three were government offices and one was the headquarters of the Qingjian industrial group, a huge engineering and construction conglomerate. These infrequent and irregular events may be related to visits by important government officials. A C4ADS report earlier this year demonstrated Russia uses GPS spoofing extensively for government VIP protection.

    Bergman suggests that the actual spoofing device is located at the center of each of the rings formed by false GPS reports. He has also observed that not all AIS/GPS receivers in the impacted area are affected, the spoofing circles tend to be about 200 meters in diameter, many false vessel positions orbit the circle counterclockwise at 21 knots or 31 knots, and some receivers are spoofed to locations other than the circle.

    Mass GPS spoofing is most easily detected and analyzed in coastal areas because of the availability of large data sets from AIS transmissions. AIS is a maritime safety system that uses GPS for location and movement information. This data is broadcast to other ships and shore stations to help prevent collisions and improve traffic management.

    The U.S. Coast Guard first experimented with receiving AIS signals by satellite in 2008. Since that time, numerous governments and commercial entities have established AIS data services using both space-based and terrestrial receivers.

    It is likely that the kinds of disruptions seen in Russian and Chinese maritime regions are occurring elsewhere. The lack of easily accessible data from non-maritime areas, though, makes this more difficult to detect.

    Confounding this problem is an apparent reluctance of many users to report disruptions. The U.S. Coast Guard Navigation Center has had only one official report a GPS problem from a user in Russian waters and one from Chinese waters, for example. Yet it is clear that thousands of vessels have been impacted in ways that must have been quite evident to their captains and crews.

    Image: Skytruth
    Image: Skytruth