Page 436 - Fundamentals of Radar Signal Processing
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percentage by which the total range-velocity coverage, defined as the

                     product of the unambiguous range and first blind Doppler, increased in the
                     staggered case as compared to the unstaggered case? In other words,
                     compute R F /R F . Show that the numerical results agree with the result
                                          ua b
                                 uas
                                      bs
                     predicted by Eq. (5.46).
               14.  Assume a set of integer staggers {k } is mutually prime. Show that
                                                              p
                     lcm{1/k } = 1. Hint #1: For any set of numbers β, α ·lcm(β , …, β } =
                               p
                                                                                                   p
                                                                                           1
                     lcm(αβ , …, αβ }. Hint #2: Use hint #1 with a = β  · β  · … · β  and the
                                                                                      2
                              1
                                        p
                                                                                 1
                                                                                                p
                     prime factorization method for finding the least common multiple.
               15.  Consider a three-pulse canceller; thus the filter coefficients are h[m] = {1,
                     –2, 1}. Suppose the clutter c[m] at the canceller input has an
                     autocorrelation function given by




                        a.   Find the clutter power spectrum on a normalized radian frequency
                           scale, S (ω).
                                    c
                        b.   The improvement factor I was expressed as the product of “gain” and
                           “clutter attenuation,” I = G·CA, in Eq. (5.48). Find the gain G for the
                           three-pulse canceller using Eq. (5.49).

                        c.   Use the autocorrelation method to find the improvement factor I for the
                           three-pulse canceller with this clutter process.

               16.  Repeat Prob. 15(c) using the frequency domain approach. The value of G
                     from Prob. 15(b) can be reused.

               17.  Repeat Prob. 15(c) using the vector matched filter approach. Recompute
                     both G and CA using the vector method.

               18.  Compute the clutter attenuation CA when using a two-pulse canceller,
                     assuming the clutter Doppler power spectrum is of the form










                       Assume F  ≤ PRF/2 and express the answer in terms of F .
                                 co
                                                                                          co
               19.  Consider an M = 32 pulse sequence of slow-time data collected with PRF

                     = 10 kHz. A radix 2 FFT algorithm is used to compute the Doppler
                     spectrum of the data. If the Doppler frequency samples are to have a
                     spacing of 100 Hz or less, what is the minimum FFT size K that should be
                     used? What is the resulting spacing of the Doppler frequency samples in
                     hertz?
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