Contested-EM & Assured PNT

NATO DIANA · Contested EM Environments — EW spectrum awareness, jamming detection & GNSS-denied navigation.

Spectrum · 0–2000 MHz

VHF tactical (SINCGARS) UHF SATCOM GPS L2 GPS L1 / Galileo E1 Cellular (LTE/5G)

Assured PNT · PACE chain

Primary

GNSS

● ACTIVE

Alternate

Vision/Map

Contingency

eLORAN

Emergency

INS DR

Position uncertainty (CEP)3 m

Threat emitter

Centre freq1575 MHz

Bandwidth (spot↔barrage)10 MHz

Power-70 dBm

PNT resilience

INS grade

VPS / map-matching aideLORAN aid

The combined spectrum sums friendly emitters, ambient signals and the threat in the linear power domain over a 0–2000 MHz grid; detected interference is classified spot (narrow) vs barrage (wide) with a jammer-to-signal (J/S) ratio against the strongest overlapped victim. Jammer energy landing in the protected GNSS band degrades L1 C/N0; below the tracking threshold the receiver loses lock and navigation falls through the PACE chain (GNSS → VPS → eLORAN → INS). Under INS-only dead-reckoning, position uncertainty (CEP) grows at the inertial grade's drift rate until an aiding source bounds it. Defensive EW situational awareness only — no transmission is performed.