eLoran as a Sovereign PNT Solution

Should National Critical Infrastructure Depend on PNT Solutions Outside National Control?

Discussions surrounding alternative, complementary, and backup Positioning, Navigation, and Timing (PNT) systems often begin with a single assumption: global coverage is the primary objective.

For critical national infrastructure, that assumption deserves reconsideration.

For energy grids, telecommunications, transportation systems, emergency services, financial networks, and defense operations, sovereign coverage may be equally — if not more — important than global reach. National resilience begins with trusted infrastructure under national control.

At the same time, interference against Global Navigation Satellite Systems (GNSS) continues to increase worldwide. Jamming, spoofing, and meaconing events are now routinely observed in contested regions and near strategic infrastructure.

Importantly, space-based alternatives are not immune to disruption. Low Earth Orbit (LEO) systems remain vulnerable to interference affecting both uplink and downlink communications. Recent disruptions to commercial satellite services in the Middle East have demonstrated the operational realities of this threat environment.

Historically, terrestrial PNT systems played a foundational role in resilient navigation and timing.

While the Transit (NAVSAT) system introduced accurate satellite-based global navigation capability, it did not initially provide continuous real-time positioning and was primarily intended for military applications. Earlier terrestrial systems such as Decca Navigator and Loran provided highly effective regional navigation services, while Omega later became the first globally available continuous terrestrial PNT system accessible to civilian users.

Notably, all major PNT architectures — including modern GNSS constellations — rely on extensive ground infrastructure and international coordination to function effectively.

This highlights several strategic realities:
• There is no “global” PNT capability without terrestrial infrastructure.
• There is no globally available service without international cooperation.
• There is no space-based PNT capability without communications dependencies.

A sovereign terrestrial PNT architecture directly addresses these dependencies.

In a sovereign eLoran deployment:
• the ground segment remains entirely within national borders,
• communications infrastructure is nationally owned and controlled,
• reliance on foreign or commercial space-based assets is minimized,
• and the system can be hardened against both physical and cyber threats.

Spectrum coordination may still require international cooperation, but operational control remains national.

Equally important, terrestrial systems avoid many of the cost, launch, sustainment, and lifecycle complexities associated with space-based architectures.

When GNSS signals are available and trustworthy, they should remain at the forefront of modern PNT solutions. However, resilience requires trusted alternatives when those signals become unavailable, degraded, or compromised.

This is where eLoran becomes strategically significant.

As part of a layered “system of systems” architecture, eLoran provides the resilient terrestrial foundation for sovereign PNT capability — supporting national resilience, infrastructure continuity, and operational assurance in contested environments.

In an era of increasing dependence on precise timing and positioning, sovereign terrestrial PNT is no longer simply a backup capability.

It is strategic infrastructure.