A PASSIVE OPTICAL SCINTILLOMETER USING A NATURALLY ILLUMINATED SCENE

ATMOSPHERIC TURBULENCE MEASUREMENT IS IMPORTANT TO ARMY ARTILLERY, AVIATION OPERATIONS AND PREDICTION OF LASER AND CHEMICAL WEAPONS EFFECTS. ATMOSPHERIC TURBULENCE-INDUCED OPTICAL SCINTILLATIONS HAVE LONG BEEN REALIZED THAT OBSERVATIONS OF THE TWINKLING OF STARS AND THE MOTION OF STELLITE IMAGES YIELD INFORMATION ABOUT THE TURBULENCE AND THE WIND SPEED IN THE UPPER ATMOSPHERE. THIS PROPOSAL ADDRESSES A DIAGNOSTIC TECHNIQUE WHICH WILL MEASURE ATMOSPHERIC TURBULENCE INTENSITY USING A NATURALLY ILLUMINATED SCENE SUCH AS A SUNLIT HILLSIDE, A FOREST OR BUILDINGS. THE PROPOSED TECHNIQUE IS BASED ON A MODIFICATION OF THE EXISTING OPTICAL SCINTILLOMETER FOR WIND MEASUREMENT DEVELOPMENT BY WAVE PROPAGATION LABORATORY OF NOAA. THE OLD SCINTILLOMETER WAS DESIGNED TO MEASURE THE CROSSWIND ONLY. HOWEVER, WITH THE HELP OF MORE SOPHISTICATED ALGORITHM, A SECOND GENERATION OPTICAL SCINTILLOMETER IS ABLE TO MEASURE BOTH ATMOSPHERIC TURBULENCE INTENSITY AND WIND USING A NATURALLY ILLUMINATED SCENE. THE INSTRUMENT WILL PROVIDE REAL-TIME CONTINUOUS MEASUREMENTS OF TURBULENCE INTENSITY IN THE FIELD OPERATION; ALTHOUGH FOGS AND SMOKES MAY OCCASIONALLY INTERRUPT THE MEASUREMENTS, THE INSTRUMENT IS INSENSITIVE TO ENVIRONMENTAL ACOUSTIC AND ELECTROMAGNETIC NOISES. IT IS COMPACT FOR EASY TRANSPORTING AND OPERATIONS.