Optical turbulence model for radiosonde data

Abstract

The structure constant, C n 2 , for optical index of refraction fluctuations is the key to the design of adaptive optical systems that minimize the effects of turbulence on laser beam propagation. This invention uses our model, which converts standard radiosonde data into C n 2 profiles. The results are compared to directly measured in situ values of C n 2 obtained by means of balloon borne thermosondes.

What is claimed is:  
     
       1. An electronic decision aid process to position an electromagnetic emission device in a location which will have a minimum of optical turbulence between it an a target, the process comprising the steps of: 
       predicting levels of optical turbulence between the target and each location in a set of potential emission locations from which the electromagnetic emission device will project an emission towards the target; and  
       selecting an optimum emission location which has a lowest level of optical turbulence discovered in the predicting step.  
     
     
       2. An electronic decision and process as defined in  claim 1 , wherein the electromagnetic emission device is an airborne laser. 
     
     
       3. An electronic decision aid device, as defined in  claim 2 , wherein said predicting and selecting steps are performed by a computer where the predicting step is performed by 
       
         
             C   n   2 =2.8 M   2 L 4/3    
         
       
       where:          M   2     =       [       (       79   ×     10     -   6          P       T   2       )          (            T          z       +   γ     )       ]     2                     
       and where T is absolute atmospheric temperature in °K, P is pressure in mb, γ is the dry adiabatic lapse rate of 9.8×10 −3  °K/m, and z is the height above ground. 
     
     
       4. A process, as defined in  claim 3 , wherein the largest scale of inertial range turbulence L is estimated by 0.1 times a thickness of a turbulent layer measured by a radiosonde.