||Only work in
local area. Subject to movement or destruction by environmental factors.
Accuracy depends on measurement tools which are usually relatively crude. Errors
works at night in good weather. Limited precision.
relatively few radio direction beacons. Accuracy limited and subject to radio
(mostly coastal). Accuracy variable, affected by geographic situation. Easy to jam or
low-frequency doppler measurements so it's sensitive to small movements at receiver. Few
satellites so updates are infrequent.