Alternative PNT network node with passive RF collection array in urban canyon environment, display showing fix holding without GPS
Positioning, Navigation, Timing

Starzl PNT

Listens to ambient RF for a position fix. It doesn't transmit and it doesn't use GPS. The same observations map nearby emitters.

The Problem

GPS is easy to lose

If the satellites are jammed or spoofed, most navigation stacks stop. Units still need a fix.

You also can't assume you'll have a network to pull a position from someone else.

The same listen-only feed that estimates your position also shows what's transmitting nearby.

The System

Listen-only

Operator with handheld PNT device in wooded environment with dappled light, passive RF collection array visible

Starzl PNT never transmits.

The same listen-only feed does two things. It figures out where you are without GPS, and it maps nearby transmitters — what they are, where they are, and how they move.

Those same observations also catch spoofing and man-in-the-middle attacks at the physical layer in under a second. The fix is computed on the device, so navigation keeps working when the network is down.

Capabilities

Specs

CapabilityMetric
Geolocation AccuracyCEP50 < 10 m (outdoors, wooded environment)
Spoof detection< 1 second
GPS Dependence0 satellites in the loop
Emission SignatureZero — listen-only, no demodulation
ArchitectureOne process for position, emitter location, and spoof detection
Where the fix is computedOn the device

One passive feed for navigation, emitter mapping, and spoof detection.

How it works

Typical path

Gray morning on weather deck with mast and antenna against flat horizon, steel and salt environment

Collect passively, detect emitters, localize, check for spoofing, and keep the fix.

01 Listen

Listens to whatever RF is already there. Nothing is transmitted.

02 Detect

Picks up what's already on the air — drone control, radar, radios — and builds a live map of who is transmitting and where.

03 Localize

Those transmitters produce your position. CEP50 < 10 m outdoors in woods. Each one is plotted on a map overlay.

04 Verify

Spoof and man-in-the-middle detection at the physical layer in < 1 second. Every fix is computed on the device.

05 Keep the fix

The position estimate stays usable when the link is degraded or gone. No GPS satellites in the loop.

Other products

Related work

RF processing, adversarial AI, and operator training.

Starzl EW

Compresses IQ, classifies emitters, and sends the result over a constrained link.

Starzl EW →
Starzl Adversarial AI

Red-team tools for models and networks. The same stack is used on infrastructure defense.

Starzl Adversarial AI →
Starzl Operator Training

Multi-day courses on AI, cyber, and OSINT. The skills stay useful when the software changes.

Starzl Operator Training →
Contact

If you want to talk through a use case

Formerly fielded as GC3Sentry.