Page 276 - Schaum's Outline of Theory and Problems of Signals and Systems
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CHAP. 51         FOURIER ANALYSIS OF TIME SIGNALS AND SYSTEMS




                  Thus, by  Eq. (5.74) we  obtain









                  Let




                  The harmonic form of  y(r) is given by  [Eq. (5.15)]





                  where Dk is the amplitude of  the kth harmonic component of  y(t ). By Eqs. (5.11) and (5.16),
                  D, and  d, are related by


                  Thus, from Eq. (5.167), with  m = 0, we obtain
                                            D, = 21d,I = 2 1   10

                                                                    I=1.71
                                                         ja(2 + ja)
                  With  m = 1, we obtain







            5.47.  The most widely used graphical representation of the frequency response  H(w) is the
                  Bode plot  in which the quantities 2010glo~H(w)l and  8,(0)  are plotted versus  w, with
                  w  plotted  on  a  logarithmic  scale.  The quantity  2010glolH(o)l is  referred  to  as the
                  magnitude expressed  in  decibel! (dB), denoted by  (H(o)l,,.  Sketch the Bode plots for
                  the following frequency responses:







                                   104(1  + jo)
                  (c)  H(w) =
                               (10 + jw)(lOO + jw)





                       For o <<  10,
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