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1 definition found
 for Manchester encoding
From The Free On-line Dictionary of Computing (18 March 2015) :

  Manchester encoding
  
      A method of transmitting bits which
     enables the receiver to easily synchronise with the sender.
  
     A simple way of signalling bits might be to transmit a high
     voltage for some period for a 1-bit and a low voltage for a 0
     bit:
  
      Bits Sent:             1     1     0     0
  
      Signal:      High    ___________
     	      Low                |___________
  
      Time: ->            .     .     .     .     .
  
     However, when several identical bits are sent in succession,
     this provides no information to the receiver about when each
     bit starts and stops.
  
     Manchester encoding splits each bit period into two, and
     ensures that there is always a transition between the signal
     levels in the middle of each bit.  This allows the receiver to
     synchronise with the sender.
  
     In normal Manchester encoding, a 1-bit is transmitted with a
     high voltage in the first period, and a low voltage in the
     second, and vice verse for the 0 bit:
  
      Bits Sent:             1     1     0     0
  
      Signal:      High    __    __       __    __
     	      Low       |__|  |_____|  |__|
  
      Time: ->            .  '  .  '  .  '  .  '  .
  
     In Differential Manchester encoding, a 1-bit is indicated by
     making the first half of the signal equal to the last half of
     the previous bit's signal and a 0-bit is indicated by making
     the first half of the signal opposite to the last half of the
     previous bit's signal.  That is, a zero bit is indicated by a
     transition at the beginning of the bit.
  
     Like normal Manchester encoding, there is always a transition
     in the middle of the transmission of the bit.
  
            Differential Manchester Encoding
  
      Bits Sent:            1     1    0     0
  
      Signal:      High  ____       __    __    __
     	      Low       |_____|  |__|  |__|
  
      Time: ->            .  '  .  '  .  '  .  '  .
  
     With each bit period half as long, twice as much bandwidth
     is required when using either of the Manchester encoding
     schemes.
  
     (1995-11-23)
  

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