UK Sentinel study reveals GPS jammer use

UK Sentinel study reveals GPS jammer use

Summary: The government-funded Sentinel project has uncovered more than a hundred incidents of GPS jammer use in the UK since January 2011

TOPICS: Security, Networking

Government-funded trials involving the police have revealed more than a hundred incidents of GPS jammer use in the UK.

The Sentinel project, which has been running since January 2011, was designed to measure GPS jamming on UK roads. The project, run by GPS-tracking company Chronos Technology, picked up the illegal jamming incidents via four GPS sensors in trials lasting from two to six months per location.

GPS jammers

The government-funded Sentinel project has uncovered more than a hundred incidents of GPS jammer use in the UK since January 2011. Image credit: Tom Espiner

"The idea behind Sentinel is to detect and locate interference," Chronos Technology's divisional manager Andy Proctor told ZDNet UK on Wednesday. "Until you physically get a jammer in your hands you can't claim 100 percent it's a jammer, because you don't know what's been causing the interference."

The Sentinel field trials of GPS jamming involved sensors in different locations. One sensor placed in a city next to some docks and a two-lane link motorway found 67 incidents of vehicles using GPS jamming over a six-month period, according to Chronos Technology's managing director Charles Curry.

"These events were real and corroborated," Curry told ZDNet UK at the GNSS Vulnerability: Present Dangers, Future Threats 2012 conference.

GPS jammers work by broadcasting a strong local signal on the same frequency as GPS, effectively drowning the weak GPS signal broadcast by satellites. People illegally jam GPS for a number of reasons, Curry told the audience at the conference at the National Physical Laboratory. These include evasion of company-vehicle or covert tracking, and stealing high-value vehicles.

In prior trials, a white van driver using GPS jamming had been apprehended by police, said Curry. The man, who was not brought to trial, was using jamming to evade company GPS tracking. ZDNet UK understands the man was apprehended as part of trials of GAARDIAN, a preceding technology to Sentinel. GAARDIAN trials ran from 2008 to 2011.

Sentinel project

Sentinel now has 20 sensors deployed in different parts of the country, Curry told the conference. The £1.5m Sentinel project is funded by the ICT Knowledge Transfer Network, and its partners include ACPO, Ordnance Survey, the National Physical Laboratory, the General Lighthouses Authority (GLA), the University of Bath, and Thatcham Security. Sensors tend to be deployed in premises owned by these organisations.

The Sentinel technology works by relaying incidents of GPS interference to a central server, Proctor told ZDNet UK. The sensor is a black box that contains a high-sensitivity GPS sensor, in some cases a rubidium atomic clock, and an embedded Linux processing unit running proprietary software using C++, PHP, and a MySQL backend database.

The eventual aim of the Sentinel project is to pinpoint GPS jamming.

GPS jamming and spoofing can have serious effects on geolocation and communications technologies that rely on GPS for positioning and timing; maritime and aircraft GPS use, and even stock market trading, can be affected by jamming, researchers said at the conference.

THV Galatea trial

In 2009, the Ministry of Defence conducted trials of GPS jamming against the THV Galatea, a buoy tender, in an area of sea near South Shields in the north of England, Professor David Last told the conference. The jamming caused the ship's systems, which were reliant on GPS, to malfunction.

Our modern society is almost completely reliant on GPS. It could be deadly.

– Todd Humphreys, University of Texas

During the trial the ship gradually lost position, and the autopilot told the ship to move off course, said Last. "Ships carry multiple [GPS] receivers embedded in multiple systems in ways people on board do not understand," Last told the conference. "When one system fails, they all fail."

This single point of failure can affect both navigational and communications instruments, Last told ZDNet UK. Instruments affected aboard the Galatea included the main electronic chart display, which was linked to the autopilot; the ship's automatic identification system; voice and data communications; and the helicopter-pad stabilisation system.

"The ship's position silently departed from the truth, and the ship's autopilot silently began to turn the vessel," said Last.

Reliance on GPS

GPS jamming and spoofing can also affect aircraft GPS and stock exchange transactions, according to University of Texas researcher Todd Humphreys, who gave a presentation at the conference.

"Our modern society is almost completely reliant on GPS," Humphreys told the conference. "It could be deadly."

Stock exchanges could be adversely affected by GPS jamming and spoofing because their datacentres rely on GPS signals to timestamp transactions, Humphries said. Any confusion caused by disruption to timestamps could cause traders to withdraw trades, he said.

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Topics: Security, Networking

Tom Espiner

About Tom Espiner

Tom is a technology reporter for He covers the security beat, writing about everything from hacking and cybercrime to threats and mitigation. He also focuses on open source and emerging technologies, all the while trying to cut through greenwash.

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  • God save GPS? Invasion of privacy more like it. True freedom is to be able opt out of being tracked and recorded.
  • How about No.

    What a load of bullshit this article is.

    People have the right to not be surveillanced if they wish so long as they aren't causing direct harm to others.

    You are clearly seem to think that all jamming should be illegal.


    Because this technology is misused incredibly frequently, it is completely legitimate to 'opt out'.
  • What a police state the UK has become. Dear God!
  • Gurpeet - GPS does not track you. Things such as your phone may use it, but all that GPS is are messages of the time it was sent.

    Matthew - GPS is incredibly important to navigation, not just for cars, but planes and boats. It's a system that is relied on heavily. If you're using a jamming device near a port, the consequences could be catastrophic.
    The technology may be misused, but it'll only ever be used by 3rd-party devices. Your phone, for example. Turn it off on that, don't try to jam the signal.
  • I have no idea if GPS jamming in the US is a crime or not, it should be. There has been a lot of discourse civil and otherwise concerning jamming for cell sites being used by police in certain situations, BART in SF being the prime example. The two types of jamming though have totally different affects on commerce and people's lives.

    Jamming GPS can cause deaths. Jamming a cell tower just infringes the 1st Amendment rights or inconveniences the phone user.

    I'm especially concerned with jamming as it relates to air travel since most of the major carriers are converting to GPS routing for aircraft. The idea is to wring out a little more profit out of a flight by using less fuel to get from one airport to another airport.
  • lol, before it was illegal for prisoners to remove their tags, and slaves to remove theirs or to burn their branding before that, now guess who the slaves on the prisonplanet are?
  • Wow. People from Facebook are either trolls or plain stupid.

    Why it is so hard to understand how GPS works? Is the difference between the transmitter and receiver so complex to understand?

    Especially for Matthew Shea: GPS does not and technically can not track you. Why? Because you are not sending any signals to GPS satellites. Why? Because your GPS device is a receiver, not transmitter.

    So nobody is tracking you, mainly because nobody needs to track you, sit down and relax.

    The only way to be tracked by using GPS-related equipment, is to use the GPS jammer. Because, in fact, the GPS jammer is a transmitter.
  • My satnav always stops working through the channel tunnelwhen I exit UK end.It will not restart until 24hrs later.OK going from UK to france no prob.Had it checked over @Honda nothing wrong with equip,this seems to be an explanation.
  • @DmitryKirsanov

    There are companies who fit GPS trackers onto their vehicles. They are basically a GPS receiver and GSM (phone) transmitter. At set intervals the phone transmits the co-ordinates "back to base" and so the HQ can "see" where all their vehicles are.

    I can download an app onto my HTC Android phone to go this too. But the wife might find out when I'm "working late" in the pub :(

    This is what people are worried about. And the naughty people in this world who might attempt to get high value vehicles or bullion vans and want to change their reported position.
  • @Keith Jamieson
    You turn off GPS on your device. You don't block GPS in the surrounding area!

    If you are required by your company to be tracked by GPS then that is between you and your employer. For example, tampering with a tachograph is illegal. Messing with GPS is potentially worse!
  • @1000099915

    I totally agree with you. I was just letting DmitryKirsanov know that there is more than "just" a receiver at work here.

    I dont own, or feel the need to own, a GPS jammer. As you say whether its illegal or not, it can be plain dangerous.
  • "God save GPS? Invasion of privacy more like it. True freedom is to be able opt out of being tracked and recorded."

    Absolutely agree with those sentences. If people are trying to protect their privacy, they have full right to do that. By the way, GPS jammers for cars at the picture above, those two small ones, have the jamming radius of 5 meters. All technical characteristics of this device you can find at Jammer Store Company's website.
  • This dependency on the Global Positioning System (GPS) is a weak link and the security accross the World is weaker than this known weak link. All failure to admit this fact of weakness will generate terrible consequences then some bureaucrat will actively amplify the harm. One reason for the bureaucrat acting in an intentionally destructive way is for promotion and other rewards.
  • @DmitryKirsanov

    Two things: That is not my photo, and this is not my facebook a/c, it's a spam a/c.

    I know very well how GPS works thank-you very much.

    You are missing the point entirely on several accounts. Like Keith Jamieson says, it's a combination of technology used, not just G.P.S.

    At the end of the day, G.P.S is being misused by all kinds of people, ranging from police to nosy civilians. It seems reasonable to me to use a jammer so long as it doesn't interfere with anybody else's setup. The range of these G.P.S jammers is very small, which is why this entire article is such a bunch of bullshit.

    You'd think from the article that GPS jammers were some kind of giant jamming field, but nothing could be further from the truth.

    It is OTT to say GPS jammers will have any influence on stock exchanges, ports etc. The examples given are very 'far out' indeed and the author should be picked up on that.

    In any case all those high profile pieces of software use validation and verification, they don't depend on the information coming in to be 100% accurate. They parse any input data to find erroneous data. It would be a stupid mistake for an engineer to make of the first order if they did not.

    Scare mongering tactics aside, I do not accept it's legitimate to passively track my whereabouts. I never consented to such a thing after all.

    You do realise that it's not simply a case of taking the battery out of your mobile phone? There is G.P.S/GSM tech in many things today that tracks your whereabouts, and hardly any of it is known to the general public although it's not exactly a secret. A small example would be that most people are unaware that taking photos with their smartphone also attaches the GPS coordinates of the place the photo was taken onto the phone.

    Who the hell signed up for that? Hardly anybody, but it's the default setting.

    tldr; **** you Mark Zuckerberg and the horse he rode in on.
  • Another example of potential GPS jamming/spoofing is the event where the Iranian military evidently spoofed/jammed GPS and caused an US UAV to land or crash in Iran. If that's actually true then it seems at the least GPS is not a secure system. Also since the frequencies in use for GPS are in the GHz range (line of sight) and I'll assume the antennas used for the GPS receivers on the UAV were on the top of the UAV. That would indicate that high power spoofing/jamming is possible. If the Iranians can do so can any other enterprise criminal, military or not.

    Take those low power jammers and stick an amplifier on them and increase the "dead-zone" radius by the square root of the output power of the amplifier.
  • high power signal jammer

    there are more and more high power signal jammer was ordered from China online store for the price are not expensive