Remote detection of small vibrations of objects across the atmosphere with the aid of a CO2 laser heterodyne system

A CO₂ laser heterodyne transceiver was used in an experimental investigation of remote detection, across the real atmosphere, of small lf vibrations of the surface of an object located at a distance of 1.85 km. Estimates were obtained of the corresponding capabilities of a coherent laser system at distances up to 10 km and for different reflection characteristics of the objects. The results indicated that it should be possible to detect vibrations with amplitudes of the order of several nanometers at distances up to 2 km.