distance-measuring equipment[′dis·təns ‚mezh·ər·iŋ i′kwip·mənt]
A radio aid to navigation that provides distance information by measuring total round-trip time of transmission from an airborne interrogator to a ground-based transponder and return. Abbreviated DME.
distance-measuring equipment (DME)
the distance from the ground station. Operating on the line-of-sight principle, DME furnishes distance information with a very high degree of accuracy. Reliable signals may be received at distances up to 199 NM (nautical miles) at the line-of-sight altitude with an accuracy of better than ¼ mile or 3% of the distance, whichever is greater. See also line-of-sight reception.