In June 2017, a French oil tanker, the Atria, lost its GPS signal as it approached the Russian city of Novorossiysk.
When the signal returned the captain noticed the position it gave was forty kilometres inland.
Nearby vessels reported similar malfunctions in their navigation systems with a total of 20 other ships impossibly located at the Gelendzhik inland airport.
Simultaneously, Uber customers in Moscow taking short trips across the city were charged for thousand-mile journeys to distant airports.
There was speculation that the security team for Vladimir Putin might be using a portable device to disrupt GPS signals to mask the Russian President’s whereabouts and protect him from possible drone attacks.
But this wasn’t an isolated incident. Researchers used data from ships’ continuous broadcasts and realised the problem was larger than anyone could have guessed.
According to a report released in March 2019 looking at GPS spoofing in Russia and Syria, there were ten thousand spoofing incidents at sea between February 2016 and November 2018, with 1,300 vessels affected. (See https://www.c4reports.org/aboveusonlystars).
It is more accurate to use the term GNSS spoofing, since “GPS” is the name of the US satellite positioning system, and GNSS, Global Navigational Satellite System, is a ‘family’ name for all systems, also including Europe’s Galileo system, Russia’s Glonass and China’s BeiDou.
GNSS spoofing involves the broadcasting of fake GNSS data to make a device think it is in different location. It can target any location-aware IoT system.
Spoofing in shipping, confusing connected devices, puts lives at risk.
Another threat is from getting incorrect timecodes. The GNSS system is built on satellites broadcasting accurate timecodes, and often used to provide an accurate clock in the correct time zone. The clock on your mobile phone usually automatically updates with data from GNSS signals.
The determination of true time underpins a vast array of services in our connected world - from ATMs to cell phone towers, stock exchanges and electrical grids.
Deceiving a device as to what the true time is by broadcasting fake signals can cause potentially catastrophic problems.
GNSS technology
The core GNSS technology hasn’t changed much since the first GPS satellite was launched in 1977.
Today there are a number of different systems - from Europe’s Galileo, Russia’s Glonass and China’s Beidou - each relying on satellites orbiting at 20,000 kilometres, which emit a radio signal that contains a timecode and a description of the satellite’s exact position.
By measuring the transmission time of the signal, GNSS receivers can determine their distance from the satellite. If the receiver can access signals of at least four satellites in its line of sight, it can determine its position in three dimensions.
How to spoof
GNSS chipsets can be easily deceived and misdirected simply by broadcasting fake satellite signals at them.
Malicious individuals, who can purchase cheap equipment online and download free code, can broadcast spoof signals, disrupting radio mast signals and interfering with emergency services.
The cost and complexity of spoofing is coming down rapidly. Pocket-sized GPS jammers are proliferating.
A few years ago, so many truck drivers on the New Jersey Turnpike were using jammers to obstruct their employers’ tracking systems that spill over interference disrupted the GPS landing system at Newark Liberty International Airport.
Our method
Shipping companies usually detect GNSS spoofing by having two GNSS receivers at either end of the vessel and comparing signals to highlight any discrepancy.
But too many companies find the investment in additional technology off putting and don’t take the spoofing threat seriously.
FocalPoint, a UK business set up by Dr Ramsey Faragher, part of the original design team for the ExoMars Martian Rover's "Seeker" visual navigation system, has been working on another solution.
Their “Supercorrelation” technology is a software upgrade to the GNSS chip which enables it to recognise and reject fake signals based on determining the angle of arrival of the signal.
When installed on a GPS receiver it can precisely determine where satellite signals are coming from.
This, in turn, enables the chip to ignore reflected and non-line-of-sight signals from positioning, both protecting the device from spoofing and enabling 10x improvements in the accuracy and integrity of GPS.
This patented innovation works at a chipset level, using sensor fusion, machine learning and signal processing.
Supercorrelation enables chips to determine spoofer signals from true signals - discarding the signal, and thus securing the device against malicious interference.
These capabilities are currently only available in military grade technology costing tens of thousands of dollars, while FocalPoint’s technology is designed to be installed at the chipset level on the GPS receiver - making it available to consumers and industry.
The Royal Institute of Navigation and the US-based Institute of Navigation recently awarded prizes to Supercorrelation in recognition of its potential.
FocalPoint is working with leading chipset companies to bring it to market.