News

What is a GPS Jamming Device? Find out how Geotab detects and eliminates threats from GPS jammers. Find out what GPS jammer look like in MyGeotab.

GPS tracking technologies are on the increase as new innovations continue to be developed. With the prevalence of smartphones and IoT devices, every location, online search, website visited, and purchase made is tracked. While many people are willing to share their location for good purposes, there is another set of people who want to hide their location.

What is a GPS Jammer?
A GPS jammer is a device used to hide where one is by sending out radio signals with the same frequency as the GPS device. Once this happens, the GPS device is unable to determine its location due to interference.

The GPS jamming unit itself is usually a small, self-contained transmitter that generates a 1575.42 MHz interference signal over a 5-10 meter radius.

Typically, the user plugs the jammer into a cigarette lighter and places the device close enough to a GPS tracker to disrupt the GPS satellite signal. Once powered up, they become fully operational in less than 20 seconds. The relatively low power and fast start-up time allow jammers to be used only when needed. Criminals will turn them off as soon as possible to avoid detection. These jammers can be purchased cheaply on the internet for less than $100.

Although the purchase of GPS jammers is strongly discouraged, various types of jammers are available for purchase online, such as physical shields, Wi-Fi / Bluetooth jammers, remote control jammers, spy camera jammers and drone jammers, to name a few.

For law enforcement and the transportation industry, GPS jammers are both a nuisance and a cause for concern. The jamming interferes with GPS vehicle tracking, also known as fleet tracking or telematics, which is a critical source of business data for many companies.

Open-platform telematics is more than just vehicle tracking - it's the collection of data on fuel consumption, idling, driving behavior, engine health and other aspects of the vehicle and operations. This vehicle data is essential to help companies manage a fleet of vehicles and achieve goals such as improving driver safety, productivity, efficiency or compliance.

Who Uses GPS Jammers?
Originally created by the government, GPS jammers were designed for military activities in which concealing the location of vehicles was crucial to the success of a mission. Jammers act as a "cloak" giving military privacy, increased security, and an overall advantage in high-risk situations.

The reasons for jamming are varied. Some speeders may use jamming to prevent detection by police and avoid fines. Criminals use GPS jammers as cover for vehicle theft or illegal activity. In the fleet world, GPS jamming could be used by a driver to prevent the employer from knowing where he is going with the company vehicle.

Where am I in the world? How a GPS System Works
To understand how a jammer works, we must first understand how the Global Positioning System (GPS) works. A GPS tracker receives microwave signals from a network of satellite transmitters orbiting the Earth at an altitude of approximately 20,200 km. Once the tracker receives signals from four or more satellites, it determines its position through a series of time and trilateration calculations.

The receiver relies on these precise and specific satellite signals to determine where it is in the world. The GPS tracking device then transmits this position and speed information to a monitoring location. Usually, this data is communicated over the cellular network.

In some cases, satellite malfunction or solar flares can temporarily disrupt the transmission of GPS signals. A GPS jammer sends out a radio signal or signal noise with the same frequency as the GPS device, to replace or distort GPS satellite signals. The GPS can then no longer calculate its position because the satellite signal is masked by interference.

How Geotab detects and eliminates GPS jamming threats
There will always be a segment of the population that wants to “fly under the radar” and attempt to defeat GPS tracking devices with GPS jammers. Fortunately, the negative effects and usefulness of jammers are minimized with Geotab devices.

Geotab's GO device tracks vehicle location, among other important data related to the vehicle in question. Data collected through the GO device is displayed in the MyGeotab software and this is where users can see if the GPS signal is disturbed.

When a GPS signal is not received, the trip history map will display a missing or interrupted trip - clearly drawing attention to a problem.

If the GPS jamming occurs in the middle of the trip, a straight line is displayed from the time the jamming begins to the point where the jamming device is turned off. Anyone monitoring the vehicle will quickly see it and can investigate the cause of the missing trip information.

More immediate jammer detection is also available. The GPS module in later Geotab GO units has a jamming detection feature that will trigger our device to report a debug log. This can be found in MyGeotab's log details, appearing as: GpsJammingDetected.

For simplified monitoring of GPS-related issues, an exception rule can be created in MyGeotab. For example, you can add a new rule that checks for these two faults:

Telematics device fault: Poor GPS quality (poor device installation or vehicle coverage) Telematics device failure: Remove device and report to dealer - GPS module not responding. This rule can be configured to trigger an alert or email for the event and be included in a scheduled report showing these faults and exceptions.
It is important to note that a GPS jammer disrupts the functionality of the GPS receiver but all other functions are unaffected. Despite loss of GPS connection, the Geotab GO device will continue to collect and send critical vehicle data such as engine data, fault codes and auxiliaries etc.