Todd Humphreys, an associate professor of aerospace engineering at the University of Texas at Austin, told Scientific American that the National Advisory Committee on Space Positioning, Navigation, and Timing (PNT) is concerned that "alien adversaries or terrorist groups could coordinate multiple jamming and spoofing attacks on GPS receivers, Severely degrade the functioning of power grids, mobile phone networks, stock markets, hospitals, airports, etc.
The Defense Department is concerned about foreign threats to U.S. GPS
The Defense Department is also concerned - and has been for years - about the proliferation and increasing capabilities of jamming systems, primarily from China and Russia.
Russia has demonstrated its ability to disrupt Global Navigation satellite Systems (GNSS) flying over its territory. It is also suspected of interfering with neighbouring countries. GNSS is a general term for a variety of satellites that transmit positioning and timing data. Our GPS is just one of many satellites that can provide this data.
As early as 2016, when the United States carried out reconnaissance missions in the Nansha Islands in the South China Sea, China seemed to show a willingness to interfere with our military drones.
Experts also believe that Iran and North Korea may have the ability to jam GPS signals.
And a home GPS signal jammers threat. Although the Federal Communications Commission (FCC) has ruled that GPS jammers are illegal in the United States, they still exist.
In 2015, pilots flying to Northeast Philadelphia Airport reported losing GPS navigation signals as they approached the runway. The culprit was a truck driver parked in a nearby parking lot who disabled the tracking device in his vehicle using a GPS jammers he had purchased.
In 2018, Congress passed the National Timing Resiliency and Security Act (NTRSA) to create a backup system for our GPS by the end of 2020. President Trump signed the bill into law in December, just months before Diana Furchtgott-Roth took office. Deputy Assistant Secretary for Research and Technology (OST-R), Department of Transportation (DOT).
Since Furchtgott-Roth joined DOT in February 2019, she has worked to meet the requirements of the NTRSA. This includes the need to set up a supplemental and backup system that users can access when GPS is not available or when a strengthened signal is needed. The need for such measures has been a requirement of DOT presidential policy since President George W. Bush signed a presidential directive on U.S. space positioning, navigation, and timing in 2004.
That same month, Trump issued an executive order calling for building national resilience through the responsible use of location, navigation, and timing services.
Furchtgott-Roth told GPS World, "We cannot allow GPS signals to become a single point of failure for transportation and other critical infrastructure sectors."
His first hurdle was that while transportation was the lead agency, congressional funding to set up a backup GPS system went to the Defense Department. This pushes the positioning, navigation, and Timing (PNT) demonstration back to March 2020.