Curious GPS Interference- Possible causes

Discussion in 'General Announcements' started by KB0MNM, Jun 14, 2020.

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  1. KB0MNM

    KB0MNM Ham Member QRZ Page

    Here is a link: which was called to my attention because of the connection to AIS ( a system that ships use to keep track of positions ) and the changes recently made to allocations in frequency for 5G ( or 4G, LTE? ) communication by the F.C.C.
    Now there are a few different theories:
    1. Someone having fun sending silly info to the AIS database server ( this sounds pretty far-fetched, because it would require a lot of work to build 'circular tracks' of dis-information ).
    2. Intentional 'spoofing', because at least three of the ships were sailing in waters where the Ukraine government may have had cause to believe that other parties had motive and equipment. Typical equipment might include "GPS Constellation Factory Testers" which can record and/or play back signals used to test new GPS equipment for the ability to reject false signals. Older GPS systems did not include the newer constellations.
    3. Non-intentional 'spoofing' involving harmonics or fundamental overload of GPS receivers by 5G/ 4G LTE base stations, whether or not in 'set-up' ( initial installation ) status.
    4. Poor integration of various systems which contribute to AIS, eg. Satellite and LTE systems.
    5. Other theories ( post 'em here... ) ???
    Yes, this is not amateur radio per se. Yet since many enjoy APRS, it should be of interest to those who follow developments in electronic navigation. One example is DGPS ( Differential GPS ), where reference stations on earth are used for corrections to satellite-based signals.
  2. KB0MNM

    KB0MNM Ham Member QRZ Page

    The data-blog link might need to be accessed manually now, starting at the dot org level, then blog. Here is just the start of the article, since a few seem interested:
    By Bjorn Bergman| May 26th, 2020|Data and technology, Data blog
    Analysis from SkyTruth and Global Fishing Watch shows ship tracks jumping thousands of miles from their true locations.

    Bjorn Bergman works with SkyTruth and with the Global Fishing Watch research team to track vessels broadcasting false automatic identification system (AIS) locations and to investigate new sources of satellite data for vessel tracking and for detecting dark targets at sea. In this blog post, Bjorn spots an unusual pattern of false AIS broadcasts concentrated at one location, Point Reyes, northwest of San Francisco on the California coast. Why would vessels thousands of miles away be suddenly popping up in circles over Point Reyes? Could this reflect an intentional disruption of the underlying global positioning system (GPS) that AIS relies on, or is there some other explanation for this pattern?

    In December 2019, SkyTruth reported on a number of locations on the Chinese coast (mostly oil terminals) where ship tracking positions from the automatic identification system (AIS) became scrambled as soon as ships approached within a few miles of a point on shore. Importantly, we knew that this was actual disruption of the underlying GPS system (or more broadly the Global Navigation Satellite System) and not just a shipboard AIS malfunction. We determined this because another source of GPS data, Strava’s heat map of fitness trackers, showed the same ring pattern. A quick recent check of the data showed that this GPS manipulation is ongoing at oil terminals in four of the cities (Shanghai, Dalian, Fuzhou, and Quanzhou) where we had detected it last year. We still don’t know if this manipulation is specifically intended to mask ship traffic or if there is some other reason for disrupting GPS.
  3. KA9JLM

    KA9JLM Ham Member QRZ Page

    I never did trust GPS, There are to many ways to disrupt it.

    Then we are in a world of hurt. :eek:

    Most anything can be jammed if the signal is strong enough.
    K3RW likes this.
  4. KA0HCP

    KA0HCP XML Subscriber QRZ Page

    The Chinese incidents clearly show a predictable pattern, and IMO is probably deliberate to obscure ship location and movements.

    Gut feel on the Point Reyes incidents is that of probably firmware/software bugs triggered by some less common input or hardware glitch. I can't find anything at your links, so just basing on your description.

    Glad somebody is watching this stuff!!! Wish I could go back to the Navy for a second career as a Cryptologic officer.
  5. KB0MNM

    KB0MNM Ham Member QRZ Page

    Some of those links involve access through LinkedIn or Facebook. That is why I copied a bit of the full article. Hindsight is 20/20. In May, the FCC unanimously approved the new authorizations- there are other factors at play here. For one, more sophisticated GPS receivers also include GLONASS constellations- thus reliance on just our (U.S.) system is not always needed- that can be a money issue. As to wishing, be careful what you wish for... I also served to 1985/1987. Thanks for your service. Thanks also to Mr. Steven Bonnell, who posted the info about the F.C.C. ( which seemed to match the AIS query elsewhere ).
    KA0HCP likes this.
  6. KA0HCP

    KA0HCP XML Subscriber QRZ Page

    -More specific reply: No reason to assume GPS is the culprit or victim. Again, the problem could be with the AIS units on the ships or perhaps with the AIS report handling system on the internet.

    -The Ukrainian and Chinese port incidents do not seem to be related.

    -Not knowing the true positions of the Ukrainian ships limits ability to analyse. However, taking the Lat/Long of Point Reyes, the antipodal Longitude is roughly 058 East, which at the same Latitude would be in Turkistan, East of the Caspian Sea, which is land locked. Closer to the Black Sea and Mediterranean, where I imagine the Ukraine ships probably are operating.

    -Drawing circles with ship locations is a bit too 'cutesy" for hackers with malignant intentions, requires extra work and is a bit obvious. Attracting attention is not good operations technique.
  7. KB0MNM

    KB0MNM Ham Member QRZ Page

    The rest of the article has a table, yet you do not have an e-mail address posted. I have other responsibilities today. Someone posted on the LinkedIn or Facebook website that the courses might be 'faked' at the AIS communications level. This would be VHF, according to that report. Yet Satellite communications and LTE may be involved- because AIS is a system. The problem is that anyone with enough money might be able to defeat one navigation system. Thankfully, not every ship relies on GPS alone. Yet there is a concern for the safety of many ships for economic reasons.
  8. KL7KN

    KL7KN Ham Member QRZ Page

  9. KB0MNM

    KB0MNM Ham Member QRZ Page

    When you say Oz, are you referring to "The land down under?" Thanks for the links.
  10. K6CLS

    K6CLS Ham Member QRZ Page


    No doubt yhe Chinese are interfering with GPR signals. First noticed a couple years ago by ships at the dock in Shanghai.

    No doubt the Russians were messing with GPS in the North Sea and Black Sea. They won't admit it but US Navy has pretty hard evidence.

    No doubt the US Navy has GPS spoofers. A couple years ago they issued a NOTAM for air users in vicinity of Fallon NV. We detected it all weekend at Black Rock. Spoofing position, but not altitude, from what I could see.

    ... No doubt the some 5G allocations will interfere with all constellations on L band.

    Unless we continue to right it.

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