Signals Cont

o    Figure shows a periodic signal decomposed into two sine waves o    First sine wave (middle one) has a frequency of '6' while the second sine wave has a frequency of '0' o    Adding these two signals point by point results in the top graph o    Original signal looks like a sine wave that has its time axis shifted downward o    This shift is because of DC Component or zero frequency component in the signal o    If  you  look  at  the  signal  in  time  domain,  a  single  point  is  there  while  in  frequency domain , two component freq.'s are there Frequency Spectrum / Bandwidth o     Frequency Spectrum: of a signal is the collection of all the component frequencies it contains o    It is shown using a Frequency domain graph o    Bandwidth: of a signal is the width of the frequency spectrum o    In  other  words  ,Bandwidth  refers  to  the  range  of  the  component  frequencies  and Frequency Spectrum refers to the elements within that range How to calculate Bandwidth? o    To calculate Bandwidth, subtract the lowest frequency from the highest frequency If  a  periodic  signal  is decomposed  into  five  sine  waves  with  frequencies  100,  300,  500, 700, and 900 Hz, what is the Bandwidth? Solution B =  f h -  f l  = 900 -100 = 800Hz