Page 480 - Fundamentals of Radar Signal Processing
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FIGURE 6.11   Effect of noncoherent integration on detection performance for a
               nonfluctuating target in complex Gaussian noise as a function of single-sample
               SNR.



               6.3.3   Albersheim’s Equation
               The  performance  results  for  the  case  of  a  nonfluctuating  target  in  complex

               Gaussian  noise  are  given  by Eqs. (6.79)  and (6.86). While relatively easy to
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               implement  in  a  modern  software  analysis  system  such  as  MATLAB ,  these
               equations do not lend themselves to manual calculation. Fortunately, there does
               exist a simple closed-form expression relating P , P , and SNR c that can be
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               computed  with  simple  scientific  calculators.  This  expression  is  known  as
               Albersheim’s equation (Albersheim, 1981; Tufts and Cann, 1983).
                     Albersheim’s  equation  is  an  empirical  approximation  to  the  results  in
               (Robertson, 1967) for computing the single-sample SNR χ  required to achieve
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               a given P  and P . It applies under the following conditions:
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                       •  Nonfluctuating target in Gaussian (i.i.d. in I and Q) noise
                       •  Linear (not square-law) detector
                       •  Noncoherent integration of N samples


                     The estimate is given by the series of calculations
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