World Security Report2015-05-13 06:34:52

The threat from low cost commercially available GPS jammers

The threat from low cost commercially available, mostly Chinese manufacture, GPS jammers is much better understood as a result of two nationally important research projects, GAARDIAN which began in 2008 and SENTINEL in 2011.

These were led by Chronos Technology Ltd and partly funded by Innovate UK, the Innovation agency within the Department of Business, Innovation and Skills. Within these two projects, which finished in 2013, Chronos brought together a consortium of experts including the University of Bath, Imperial College, London, Ordnance Survey, General Lighthouse Authorities, BT, National Physical Laboratory, Thatcham Vehicle Security and the Transport section of the Association of Chief Police Officers.

As a result of this research, UK Government is now much better informed about the threat from GPS Jamming including its impact on serious crime and the potential vulnerability of critical infrastructure. These projects have also helped to inform US Government about the nature and extent of the problem by linking agencies within the two countries with common concerns.

GPS Jamming research as long ago as 1996 had shown through actual field trials that a 10 Watt jammer in the centre of London would deny GPS at Stansted, Gatwick and Heathrow. Luckily in those days hardly anyone outside of the military was using GPS for positioning, navigation or timing. Now the technology is ubiquitous, it's in our cars and phones, in tracking devices including children and pet tags. It has such diverse applications as providing timing for critical infrastructure and enabling train doors to open at the correct places. 10 Watts does not seem that powerful, however at ground level it is only has to compete with a signal power from a satellite approximately 12,000 miles away - equivalent to a car headlight. 10 watts basically wipes out all reception over a distance of many miles.

Consider that same experiment conducted in London today! Go on any GPS Jammer web site and you will be spoilt for choice with devices that could bring London to a halt in moments.
Within GAARDIAN, the research took a practical view of whether (in the first instance) these devices were detectable - some are quite low power and go in the cigarette lighter or your pocket. SENTINEL followed on by researching the actual geolocation of the devices.

The outcome is a GPS Jamming toolbox of techniques that can identify the direction of a modestly powerful jammer at a range of a mile down to working out in which car or pocket the jammer is hidden. The problem is not unique to the UK, agencies around the world, including law enforcement, homeland security, border control and critical infrastructure security are now using relevant parts of the jamming detection toolbox to mitigate the threat and in some cases actually apprehend and defeat serious organised crime.

Chronos presented the current state of knowledge at Counter Terror in Olympia in April 2015 through examples of first-hand practical experience and well documented instances in the public domain. These examples have all been gathered through the on-going research and productisation activity either by working closely with relevant agencies or interviewing relevant people who detected the jammers. Now Chronos classifies jammer use into six application areas.

These are:
• Personal Aggravation Disruption
• Personal Privacy
• Criminal Privacy
• Organised Crime
• Civil Disruption/Terrorism
• Nation State

Personal Aggravation Disruption
Examples include the selfish use of mobile phone signal jammers to stop phone ringing, or people talking loudly in quiet carriages on trains. One excellent example was detected in the USA using a Chronos hand-held detector where a Priest had purchased and was using a device to stop phones going off during his sermon. In these cases the jammers used were multi-band which not only jammed the mobile phone signal but also jammed the GPS signal and hence the ability to detect. It is not clear whether this will have an adverse impact on train doors which use GPS location to operate. However there are reported instances of doors not opening in some London trains resulting in 5 minute delays at the station whilst the train electronics are "re-booted" and further disruption with backed-up trains along the lines.

Personal Privacy
Personal privacy often relates to the need to evade fleet tracking or anti hi-jack geofencing systems. Jammers have been recovered from a number of commercial fleet vehicles as a result of police operations where the jammer has been detected. One rationale for use is that the time sheet does not quite match up to where the driver was at a certain time; other examples seen are that the driver wanted to be somewhere else - in one instance this was a lunchtime gym session. An example of jamming geofencing anti hi-jack technology was where a truck driver wanted to spend a night at home which was more than a mile off the highway. The fleet tracking system was geofencing to a mile from the highway on his route. He used a jammer at the truck stop then drove home, spent the night at home, drove back to the truck stop the next day and switched off the jammer, continuing on his way. The fleet tracking system thought he had been at the truck stop overnight. He was detected because the cell site owner conducted a long term monitoring test at the cell site to get to the bottom of why it failed for up to 8 hours on some nights.

Criminal Privacy
Examples of criminal privacy include defeating ankle tag technology or the concern by the criminal that he is being covertly tracked. Detection of one recent example of GPS jammer use for criminal privacy resulted in the arrest of two suspects using a cigarette lighter style jammer because they suspected they may be tracked using covert GPS based technology.

Organised Crime
Jammers are now regularly being discovered used for organised crime such as the theft of high value cars, builders' vans or plant. The criminals will assume that GPS tracking technology is being used and will use a jammer to defeat both the GPS tracker as well as its ability to send the GSM data message via the mobile data network regarding its location back to the tracking agencies operations centre. The vehicle or plant can then be taken to a "chop shop" and broken up or exported in a container sometimes with a jammer accompanying the vehicle throughout the export process. There is evidence now that more powerful battery operated jammers are being used by serious organised crime. These have a much greater range than the cigarette lighter style devices and jam the mobile phone signals as well as GPS.

Civil Disruption and Terrorism
Currently it is not clear if GPS jammers have been used in episodes of civil disruption. However, relatively high powered jammers can be bought over the internet with power capability similar to or greater than that used in the 1996 experiment. These would have the ability to disrupt GPS reception over wide areas such as over the entire City of London and could compromise (for example) the accuracy of time stamping technology used in high frequency trading applications.

Nation State
North Korea has demonstrated intentional high powered GPS jamming to disrupt major services operated by South Korea on a number of occasions over the last few years and generally over many days. The evidence is well documented by Research undertaken by Yonsei University, South Korea and has shown disruption to the mobile networks, planes and ships. The situation is so serious that South Korea has now instigated a plan to build a new network of land based Position, Navigation & Timing technology known as eLoran. This eLoran network will become operational over the next 2 years. eLoran is the only viable technology that can mitigate GNSS jamming and it is of concern that the French Government has recently decided that it will turn off its LORAN transmitters.

The SENTINEL research project is still operational and continually delivering evidence of on-going jamming at a number of locations scattered across the UK. Chronos is working with many agencies and organisations around the world to mitigate the threat and enable local assessment of vulnerability. Currently the evidence shows an increasing use of jammers and in particular, one sensor that has been deployed in central London since 2013 shows a 50% increase in jamming events in two years. The same sensor has recorded more than 150 events of greater than 60 seconds from January to April 2015.

The threat is not going away and one day there will be serous disruption to everyday activities caused by a significantly powerful GPS jamming event.

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