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GPS denial is no longer a theoretical future threat. It is the environment in which modern forces increasingly operate.
China has invested heavily in space and counterspace capabilities designed to degrade U.S. positioning, navigation, and timing. Other state and non-state actors are following close behind. Cheap jammers, spoofers, and electronic warfare tools now allow adversaries to disrupt GPS and radio frequency navigation with minimal funding or expertise. The result is a battlespace where signals cannot be assumed.
From space-based mapping of interference to fiber-optic drones appearing on today’s front lines, the evidence is clear: the electromagnetic spectrum is contested, fragile, and increasingly hostile. What is new is not the existence of GPS interference, but its persistence, scale, and observability across domains. In this new theater, an emerging truth is glaringly obvious: forces that continue to depend on GPS alone will find themselves fighting blind and without access to critical systems.
I am not a neutral party: I started a company that works to equip U.S. warfighters with contested autonomy at scale from orbit to seabed. That interest is informed by experience and dedication. I am a retired U.S. Air Force officer, where I served as an AC-130 aviator, weapons systems officer, and U.S. special operations drone squadron commander.
Why GPS Disruption is No Longer a Niche Problem
Unclassified assessments from the intelligence community and senior U.S. officials have consistently warned that GPS jamming and spoofing are not isolated incidents and instead are persistent features of modern conflict.
Space-based radio frequency analytics now routinely detect and geolocate global navigation satellite system interference from low Earth orbit. Commercial providers publish interference snapshots across regions ranging from eastern Europe to approaches in South America, with direct relevance to U.S. combatant commands.
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.
GPS Denial is a Cyber-Physical Security Problem
U.S. policy explicitly frames position, navigation, and timing risk as a cybersecurity problem for critical infrastructure and defense users. In 2024, Ukraine publicly targeted a Black Sea offshore platform it said Russia used for global positioning system spoofing, citing the hazard to civilian navigation. Civil aviation advisories and workgroup reports reflect the scale and persistence of interference and spoofing across the Baltic Sea, Black Sea, and Eastern Mediterranean.
These threats are no longer confined to conflict zones. Organized crime groups have employed GPS jammers inside the United States to disrupt the trucking industry. Taken together, these incidents make clear that GPS interference is not only a signal anomaly, but also a cyber-physical attack delivered through the antenna and receiver chain. This threat is one that acquisition programs should treat as part of the attack surface rather than a situational anomaly.
A Warning from the Frontlines: Fiber-Optic Drones
One of the clearest indicators of how hostile the radio and signal environment has become is the rise of fiber-optic-controlled drone use in Ukraine.
Fiber-optic drones work because they cannot be easily jammed; a jammer cannot interfere with a physical cable attached to a human-controlled station. Their limitations, however, are severe. The spooled fiber restricts range, adds weight, snags easily, and can be disabled with a single cut, while also revealing the warfighter controlling the system. These platforms are not elegant solutions. They are field-expedient workarounds adopted because radio-frequency control and GPS have become unreliable.
This does not mean that radio-frequency navigation has failed universally. Where interference density remains low or spectrum control is localized, radio-frequency control can still be effective. It does not, however, scale reliably under saturation. What has changed though, is that contesting and disrupting radio-frequency navigation is a proven and effective tactic for neutralizing the United States and Allies’ asymmetric advantage in precision warfare.
This shift should concern the U.S. military. It demonstrates that when the spectrum collapses, even technologically advanced forces revert to brittle stopgaps unless alternatives are available. Recent U.S. Navy electromagnetic warfare exercises incorporating fiber-optic drones acknowledge this reality, but broader doctrinal and acquisition changes are still required.
What the Joint Force Needs
The modern joint force should be capable of deploying and sustaining hundreds of thousands of autonomous systems across space, air, surface, littoral, and deep-ocean domains. These systems should operate in controlled swarms and waves, be attritable by design, and remain effective despite cheap jammers and theater-scale signal interference.
Autonomy can no longer assume constant communications. Navigation systems must continue functioning even when GPS is degraded or denied. Design choices should favor commodity sensors and intelligent software over exotic, fragile hardware that cannot scale or survive in contested environments. These challenges extend beyond military platforms: global navigation satellite system interference increasingly affects civilian aviation, maritime navigation, and critical infrastructure operating in the same environments.
Why Existing Alternatives Fall Short
There is no shortage of proposed alternatives to GPS, but each has limitations that prevent it from serving as a universal solution on its own. Quantum sensors offer long-term promise but remain difficult to ruggedize and are constrained by size, weight, power, and sensitivity to vibration and electromagnetic interference. Magnetic navigation can be effective in well-mapped regions, but it is vulnerable to platform-generated noise and urban ferrous clutter and is not well-mapped or reliable in most overwater areas. Gravity-based navigation relies on dense gravity models and highly stable platforms that are difficult to achieve operationally. Vision-only navigation degrades rapidly in clouds, haze, glare, low-texture environments, and, importantly, over water.
Each of these approaches addresses a specific failure mode, and none of them offer a scalable backbone for sustained, cross-domain operations under active denial.
What Works Today: Software-First Resilience
Some of the most promising solutions already exist, and they do not rely on overpowering adversaries or deploying exotic hardware.
Localized, onboard software can detect GPS spoofing and jamming by identifying inconsistencies at the measurement level and cross-checking them against independent cues, including inertial measurement units, vehicle dynamics, timing behavior, horizon geometry, and kinematic constraints. When anomalies are detected, systems can degrade gracefully to signal-free navigation rather than failing outright.
This approach treats navigation interference as a cyber-physical attack delivered through the antenna and receiver chain. It is fundamentally a software and estimation problem, not a hardware arms race. Because it scales across multiple platforms and domains, it is suitable for both high-end aircraft and attritable systems.
Making Contested Autonomy the Baseline
The clearest way forward is to make contested autonomy the default rather than the exception.
This approach recognizes that navigation systems must continue to function when GPS, communications, and vision are intermittent or unavailable. Instead of relying on any single sensor or fragile signal, systems maintain state by fusing multiple imperfect cues which combine inertial measurements, vehicle dynamics, and opportunistic environmental information through software-driven estimation. The emphasis shifts away from brittle dependencies and toward contested autonomy that can operate within the size, weight, and power constraints of both manned and unmanned platforms.
This reflects operational reality. Global navigation satellite system interference is now observable from space, and fiber-optic drones are proliferating in a toxic radio and signals environment. Navigation systems should be designed for the environment that exists today, not the one assumed in legacy requirements.
Actions Leaders Can Take Now
Adapting to GPS denial and contested environments does not require entirely new programs; it requires changes to requirements, testing, and evaluation.
Today’s requirements’ processes still assume GPS availability as a default condition rather than a contested variable, allowing programs to meet paper thresholds while failing under real-world denial. Operational testing frequently treats extended GPS and communications denial as an edge case, relying on scripted vignettes instead of prolonged exposure. Acquisition incentives continue to reward hardware milestones and certification over software iteration, making fielding exquisite platforms easier than adaptable autonomy.
Contested autonomy should be elevated to a core performance requirement, with systems routinely evaluated against explicit navigation accuracy, drift, and mission-completion thresholds under GPS-out, communications-out, and low-visibility conditions. Performance under these conditions should directly inform milestone decisions, production scaling, and platform selection.
Investments should favor approaches that can be updated, reconfigured, and redeployed through software changes rather than requiring hardware redesigns or lengthy recertification cycles. Space-based interference intelligence should inform real-time autonomous mode switching. Training and exercises should measure navigation performance during under sustained denial — particularly over vast maritime environments — with results captured and fed back into system requirements and design.
Conclusion
Global positioning system denial is the current and future operating environment. From space-based interference mapping to fiber-optic drones on the front lines, the picture is clear: the spectrum is contested, cheap jammers scale quickly, and traditional navigation assumptions no longer hold.
The joint force cannot depend on fragile links or exotic hardware. It needs autonomy and navigation systems that continue working when the global navigation satellite system, communications, and vision are unavailable. Contested autonomy that is software-driven, platform- and hardware-agnostic, and suitable for attritable platforms offers an affordable, practical, and scalable path forward.
Forces that adopt this model now will maintain the mission when signals fail. Those who wait will fight blind.
Jesse Hamel is a retired Air Force officer who served as an AC-130 aviator and U.S. Air Force weapons officer. He also served as an Air Force Special Operations Command drone squadron commander. After retirement, Hamel attended the Massachusetts Institute of Technology, where he studied advanced machine learning techniques that do not require perfect signals. He founded VICTUS to operationalize that approach.
Jesse Hamel is a retired Air Force officer who served as an AC-130 aviator and U.S. Air Force weapons officer. He also served as an Air Force Special Operations Command drone squadron commander. After retirement, Hamel attended the Massachusetts Institute of Technology, where he studied advanced machine learning techniques that do not require perfect signals. He founded VICTUS to operationalize that approach.
Image: Senior Master Sgt. Joshua Allmaras via DVIDS.
