Global Navigation Satellite System: Global Positioning Under Attack from Jamming and Spoofing

GPS (Global Positioning Service) is the major system used in the US for navigation and geographic positioning. GPS is one of the five available Global Navigation Satellite Systems (GNSS). The other systems include QZSS (Japan), BEIDOU (China), GALILEO (EU) and GLONASS (Russia).

GPS is the oldest of these systems and started in 1978. It was originally used by the US military and then made available for global use in 1994. Of these systems, GPS still remains the most accurate, but lately has been criticized for susceptibility to jamming and spoofing.

GNSS can be jammed easily with an RF signal that is broadcast strong enough in the same frequency band. A jammed signal can cause havoc for GPS users, like air traffic control and mobile phone users.

GNSS can also be spoofed when transmission signals are sent in the same frequency band but with incorrect positioning. This can cause the user to incorrectly interpret their current position.

Jan van Hees, business development director at Septentrio, said that “jamming involves making so much noise that the [satellite signal] disappears. Spoofing is like a phishing attack on the signal.”

Jim Platt, chief of strategic defense initiatives at the Cybersecurity and Information Security Agency’s National Risk Management Center, said that “since GPS signals can be jammed or spoofed, critical infrastructure systems should not be designed with the assumption that GPS data will always be available or will always be accurate.”

Dana Goward, president of Resilient Navigation & Timing Foundation, said that “GPS is so important in our everyday lives. If it were to go away for a significant amount of time, I am sure lives would be lost. If GPS were to fail, it’s impossible to predict the exact sequence of events. Transportation and first responders will suffer immediately. There could be more accidents. Cellphones and internet will begin to degrade, but it’s hard to say how much and how quickly.”

The US military realizes that there are problems with the current system and has asked for assistance. “Adversaries have long recognized our dependence on GPS and have proliferated technologies to degrade, deny and spoof GPS signals for civil and military users. We are pursuing modernization efforts across the entire GPS architecture to include upgrades in space, ground and user segments.”

A report by the Government Accountability Office (GAO) said that the US military should “consider selecting the most resilient technologies as the cornerstone of the PNT (position, navigation, and timing) suite for military missions, rather than defaulting to GPS.”