Doppler Effect

Doppler Effect is a story-related gameplay trophy and achievement in Call of Duty: From the Cold. It is unlocked after completing the level Under the Radar on any difficulty.



Trivia
The Doppler Effect is associated with the change of wavelength of, among many things, Radar. Ironically Doppler Radar has the ability to detect enemy aircraft flying under the range covered by conventional Radar thus making Flying Under the Radar virtually impossible.