Types of Communication Systems:

i)   Simplex (SX) Communication System:

        The communication system that is capable of one way transmission is called simplex transmission system.  In simplex type you have one unit equipped with one transmitter and on the other side equipped with one receiver but communication is done only one way by transmitter.

Simplex Communication System

For example, television broadcast system in which there is one transmitter and more than one receivers that only receives information sent by transmitter.

ii) Half-Duplex (HDX) Communication System :

      The communication system in which information flows in both directions but the flow is only one way at a given time is known as half-duplex (HDX).

      In this type, you have one unit equipped with transmitter as well receiver at one end and a transmitter-receiver at the other end but information can't flow simultaneously in both directions.

Half-Duplex Communication System

    An example of half-duplex system is two parties "walkie-talkie"  where both parties can transmit and receive but only one can transmit at a time.

iii) Full-Duplex (FDX) Communication System :

In full-duplex communication simultaneous communication is accomplished in both directions.

Full-Duplex

  
Full-duplex Ethernet connections work on the principles of full-duplex where data packets are received and sent simultaneously at a given time.

                                                         

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