Atmospheric studies and applications with infrared heterodyne detection techniques

With the advent of stable, cw infrared lasers with moderate output power capabilities in the mid 1960's came the idea of using heterodyne detection, a mature radio frequency technique, in the infrared. This technique was first applied in radar and communications applications; however, it became apparent that infrared lasers and heterodyne detection techniques would be useful in a number of atmospheric measurement applications. The level to which these techniques are being put to use in field measurements is shown using two developed flight instruments as examples.