A full-duplex system allows communication in both directions, and unlike
half-duplex, allows this to happen simultaneously. Land-line telephone networks
are full-duplex since they allow both callers to speak and be heard at the same
time. A good analogy for a full-duplex system would be a two lane road with one
lane for each direction. Examples: Telephone, Mobile Phone, etc.
Two way
radios can be, for instance, designed as full-duplex systems, which transmit on
one frequency and receive on a different frequency. This is also called
frequency-division duplex. Frequency-division-duplex systems can be extended to
farther distances using pairs of simple repeater stations, owing to the fact the
communications transmitted on any one frequency always travels in the same
direction.
Citation:
Duplex (telecommunications). (2006, November 3). In Wikipedia, The Free
Encyclopedia. Retrieved 07:45, November 12, 2006, from http://en.wikipedia.org/w/index.php?title=Duplex_%28telecommunications%29&oldid=85399120