LocataNet Achieves Autonomous GPS-Denied Positioning Breakthrough for the USAF

In December 2012, Locata Corporation announced confirmation of a landmark milestone: its terrestrial LocataNet™ positioning network demonstrated full operational independence from satellite-based GPS while delivering equivalent—or superior—positioning, navigation, and timing (PNT) performance to U.S. Air Force aircraft. The validation followed rigorous, independent USAF testing conducted at the White Sands Missile Range.

The results were decisive. A LocataNet deployed across the range functioned entirely without GPS signals and still matched the accuracy derived from the full GPS satellite constellation. This unprecedented outcome led directly to a sole-source contract award for Locata to implement a permanent network spanning more than 2,500 square miles of the New Mexico test environment.

Independent Validation Through Critical Design Review

Before flight trials commenced, the system underwent a stringent USAF-directed Critical Design Review. Only after passing that evaluation was a temporary LocataNet installed across approximately 1,350 square miles (3,500 square kilometers) of the range for live aircraft testing.

The Air Force conducted side-by-side comparisons between Locata’s compact 5-by-5-inch airborne receiver and the military’s established “Truth Reference System”—a substantially larger rack-mounted configuration described by the USAF as one of the most precise reference solutions available for both ground and flight testing. Performance metrics gathered during the campaign demonstrated that Locata not only satisfied contractual tracking and positioning requirements but surpassed them in multiple areas.

Autonomous Centimeter-Level Accuracy Without GPS

Among the most significant achievements documented in the USAF report was centimeter-scale positioning delivered in a fully GPS-denied environment. Aircraft flying up to 30 miles (50 km) from the network, at speeds reaching 350 mph (550 km/h) and altitudes of 25,000 feet, maintained horizontal accuracy of approximately 2.5 inches (6 cm) and vertical accuracy near 6 inches (15 cm). Such performance without reliance on satellite signals represented a global first in positioning technology.

Network-Wide Nanosecond Time Synchronization

Equally notable was the system’s time distribution capability. Within minutes of activation, the entire White Sands Locata network synchronized to nanosecond-level precision. That synchronization persisted throughout testing—even under severe weather conditions—until deactivation. Because precise timing is foundational to any GPS-style positioning architecture, demonstrating nanosecond synchronization without satellite input conclusively proved the robustness of Locata’s terrestrial design.

Extended Range Through Signal Amplification

USAF evaluations further established that commercial-grade Locata transmitters—identical to those used in industries such as mining—could be adapted for extended operational reach. By attaching a standard 10-watt amplifier, engineers enabled aircraft signal acquisition and tracking at distances approaching 60 miles (100 km). Greater coverage could be achieved through higher-power amplification, indicating scalable range without redesigning core infrastructure.

Reliable Tracking Under Demanding Flight Dynamics

Prior to these trials, Locata deployments had primarily supported ground vehicles operating in localized environments. At White Sands, however, the system was required to maintain performance during complex aircraft maneuvers. Test profiles included banking turns, angular and linear accelerations, airspeeds up to 300 knots (560 km/h), and altitudes reaching 30,000 feet above sea level. Real-world testing verified that the receiver maintained stable tracking and accuracy under these dynamic aviation conditions.

Aircraft-Certified Antenna Development

To meet USAF specifications, Locata collaborated with Cooper Antennas Ltd. to design and manufacture aircraft-certified quadrifilar helix antennas. These units were deployed both on ground transmitters and onboard test aircraft. Performance throughout the evaluation period confirmed the effectiveness of the new antenna architecture and validated Locata’s engineering research.

Operational Integration at White Sands

Following the successful trials, the USAF moved to integrate Locata signals as a complementary solution capable of “filling in” when GPS transmissions are degraded or intentionally jammed. Unlike satellite-dependent systems, Locata transmitters can remain permanently installed across the range or repositioned as mission requirements evolve. The result is an always-available, high-accuracy PNT infrastructure independent of satellite availability.

Enabling Next-Generation Ultra High Accuracy Reference Systems

The Air Force report identified Locata as a critical enabler for achieving performance objectives within the USAF’s developing Ultra High Accuracy Reference System (UHARS). The UHARS initiative is being advanced by the 746th Test Squadron, a unit operating under the U.S. Department of Defense’s Central Inertial and GPS Test Facility at Holloman Air Force Base.

UHARS is intended to establish the next-generation “truth” benchmark for testing advanced navigation and navigation warfare systems in contested or GPS-denied environments. Incorporating Locata technology ensures that centimeter-level accuracy remains attainable even when satellite signals are disrupted.

The Role of the 746th Test Squadron

With more than five decades of expertise, the 746th Test Squadron serves as the Department of Defense’s primary facility for evaluating GPS user equipment, inertial navigation systems (INS), and integrated GPS/INS guidance solutions. The squadron leads the tri-service GPS Test Center of Expertise, coordinating Army, Navy, and Air Force evaluation initiatives.

Its capabilities span receiver compatibility testing prior to satellite launch, on-orbit signal assessment, performance analysis in global airspace, electronic combat evaluation, and GPS space and control segment monitoring. The White Sands validation of Locata therefore carries substantial technical weight within the defense navigation community.

Transforming the Positioning Technology Landscape

Commercially, Locata collaborates with major industry partners—including Leica Geosystems and Hexagon—to deliver centimeter-accurate positioning solutions for industrial, government, and enterprise applications. Yet demonstrating wide-area, military-grade performance without GPS across a massive operational test range elevates the technology into an entirely new category.

By replicating the functional architecture of satellite positioning networks through terrestrial infrastructure, LocataNet expands reliability and coverage in environments where GPS is unreliable, obstructed, or deliberately jammed. The White Sands deployment marks a pivotal shift in how high-accuracy positioning can be delivered—establishing a resilient, ground-based alternative that operates independently of space-based systems.

As validated by the USAF, autonomous terrestrial positioning networks capable of centimeter precision and nanosecond synchronization are no longer theoretical concepts. They are operational realities reshaping the future of positioning, navigation, and timing technology.