An investigation into the practicability of using an electromagnetic-acoustic probe to detect air turbulence

This paper describes some theoretical and experimental investigations into the possible use of the reflexion of electromagnetic waves by an acoustic shock wave. Satisfactory detection of reflected microwave signals has been achieved in a number of experiments and the Doppler frequency shift of the signals has been shown to give a satisfactory indication of the wind velocity along the line of sight of the EMAC (ElectroMagnetic-ACoustic) probe arrangement. Remote indication of radial wind velocity has been achieved at ranges in excess of 450 m (1500 ft) and greater ranges should be obtained with improved experimental equipment.