Page 251 - Fundamentals of Radar Signal Processing
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(i.e., sample the same range bin for each pulse). The filter output for pulse m is

               sampled at t = t  + mT, giving y (t  + mT) = s (0) again.
                                                                    p
                                 l
                                                    m
                                                       l
                     If  the  sample  taken  at  time tl after pulse transmission is associated with
               range bin l, the M samples so obtained form a discrete constant-valued sequence
               y[l, m] = sp(0), 0 ≤ m ≤ M – 1. The discrete-time causal matched filter in the
               slow-time (m) dimension for such a sequence is h[m] = αy*[M – 1 – m]; with α
               = 1/s (0), h[m] = 1 for 0 ≤ m ≤ M – 1. The output of this discrete-time matched
                     p
               filter is


















                                                                                                       (4.62)

               The peak output will occur when the two functions in the summand completely
               overlap, which requires m = M – 1; then






                                                                                                       (4.63)

               Equation (4.63) indicates that in pulse-by-pulse processing, matched filtering of
               the slow-time sequence from a given range bin reduces to coherently integrating

               the  slow-time  samples  in  each  range  bin,  and  the  resulting  peak  output  is
               identical to that obtained with a whole-waveform continuous matched filter of
               Eq.  (4.55).  Figure  4.14  illustrates  the  row  of  slow-time  samples  that  are
               integrated (after matched filtering of the single pulse in fast time) to complete
               the matched filtering process for the pulse burst. This operation is performed

               independently for each range bin.
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