Page 268 - Fundamentals of Radar Signal Processing
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FIGURE 4.25   Output of matched filter for an LFM waveform: (a) βτ = 10, (b)

               βτ = 100. The dotted line is the output of a matched filter for a simple pulse of
               the same duration.



                     Simple and LFM pulses of the same amplitude and duration will have the
               same peak power at the matched filter output and achieve the same output SNR
               in accordance with Eq. (4.13). However, for an LFM pulse and a simple pulse
               of  the  same  amplitude  to  have  the  same  fast-time  Rayleigh  resolution  at  the
               output of their matched filters, the simple pulse must be shorter than the LFM
               pulse by the factor βτ. The energy in the simple pulse and the SNR achieved are
               then  also  less  by  the  factor  of βτ.  In  other  words,  the  LFM  waveform  with
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