14 CLASSIFICATION OF NOISE , EFFECTS OF NOISE IN COMMUNICATION SYSTEM

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 CLASSIFICATION OF NOISE :

NOISE : It is an unwanted energy signal ,which added at channel

noise can be divided in to two types (a)  External noise  (b) Internal noise


(a) External noise :  i) atmospheric noise ii) extra terrestrial noise iii) man made noise

(b) Internal noise  :  i) thermal noise ii) shot noise iii) transit time iv) miscellaneous noise 


EFFECTS OF NOISE IN COMMUNICATION SYSTEM :

  • noise will degrade the system performance .
  • the receiver can not understand original message signal .
  • reduce the efficiency of communication system


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