Category:GNSS-Denied Navigation

GNSS (Navstar GPS (USA), GLONASS (RU), Beidou (CN), Galileo (EU)) might encounter jamming or spoofing. See https://gpsjam.org/ for daily maps of interference.
This page lists some alternative (marine) navigation strategies:

cross bearings

• https://de.wikipedia.org/wiki/Kreuzpeilung

dead reckoning

• https://en.wikipedia.org/wiki/Dead_reckoning

celestial navigation

• https://en.wikipedia.org/wiki/Celestial_navigation

radio direction finding

• https://en.wikipedia.org/wiki/Direction_finding

R(anging)-Mode

• https://en.wikipedia.org/wiki/Trilateration

Like GNSS, land based r-mode calculates distance by TDoA (Time Difference of Arrival)

MF (medium frequency)

VHF (very high frequency)