A War on the Rocks article titled “When GPS Goes Dark: Building a Force That Navigates from Orbit to Seabed” by Jesse Hamel argues that GPS denial is no longer a hypothetical threat but a routine condition in modern warfare. Cheap jammers, spoofing systems, and electronic warfare tools increasingly disrupt navigation and communications, meaning militaries can no longer rely on GPS alone.
Future forces must operate through contested electromagnetic environments by using resilient, software-driven navigation that fuses multiple sensors and autonomous systems across domains. Hamel writes:
At the tactical level, the barrier to entry is dangerously low. Backpack– or vehicle-mounted jammers built from cheap software-defined radios are now routine in Ukraine and visible across multiple theaters. These tools require little training, scale rapidly, and create unpredictable navigation outages far beyond major-power conflict scenarios. Any force operating today should assume GPS degradation as a baseline condition.
Real-world examples underscore this vulnerability. A Ukrainian assessment reported by The Washington Post finds that U.S.-supplied HIMARS and Excalibur GPS-guided artillery have been heavily disrupted by Russian electronic warfare. Persistent jamming has caused targeting errors—sometimes exceeding 50 feet—forcing Ukraine to scale back use and highlighting weaknesses even in advanced U.S. precision weapons.
Russia’s jamming of the guidance systems of modern Western weapons, including Excalibur GPS-guided artillery shells and the High Mobility Artillery Rocket System, or HIMARS, which can fire some U.S.-made rockets with a range of up to 50 miles, has eroded Ukraine’s ability to defend its territory
Technologies that protect GNSS are increasingly vital. Hexagon’s GAJT-AE3 is an advanced anti-jamming system providing multi-constellation, multi-frequency PNT protection, withstanding jamming from seven directions and delivering 65 dB interference suppression. Its compact design for UAVs, missiles, and aircraft also offers real-time jammer detection and situational awareness for reliable navigation in contested environments. Hexagon writes:
Welcome to the anti-jam revolution. For the first time, the GAJT-AE3 provides multi-constellation, multi-frequency (MCMF) GNSS jamming protection. Keep your positioning, navigation, and timing (PNT) operations on track with protection from jamming in seven simultaneous directions per band. The GAJT-AE3 also protects and supports L-Band corrections, Iridium PNT, as well as M-Code on GPS L1 and L2 for military applications.
The GAJT-AE3 provides multi-jammer direction finding for best-in-class protection and situational awareness. With a federated architecture and compact size, the GAJT-AE3 integrates seamlessly into UAVs, missiles, and military aircraft. Already using the GAJT-AE2? Easily upgrade to the GAJT-AE3 with the same form factor.
Read more here.
