Page 258 - Fundamentals of Radar Signal Processing
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(4.71)

               Substitute s′ = s – mT







                                                                                                       (4.72)

               If the complex ambiguity function of the single simple pulse x (t) is denoted as
                                                                                         p
                (t, F ), the integral in Eq. (4.72) is  (t + (n – m)T, F ). Thus
                                                                                 D
                       D
                 p
                                                             p


                                                                                                       (4.73)

                     The  double  sum  in Eq.  (4.73)  is  somewhat  difficult  to  deal  with.
               Obviously, all combinations of m and n having the same difference m – n result
               in the same summand in the second sum, but the dependence of the exponential

               term on m only prevents straightforward combining of all such terms. Defining
               n′ = m – n, it can be shown by simply enumerating all of the combinations that
               the double summation of some function f [m, n] can be written (Rihaczek, 1996)







                                                                                                       (4.74)

               Applying the decomposition of Eq. (4.74) to Eq. (4.73) gives













                                                                                                       (4.75)

               The geometric series that appears in both halves of the right-hand side of this
               equation sums to
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