A communication device is disclosed which is comprised of: a transmitter
for transmitting an ultra wide band wireless wave pulse; multiple
receivers which are disposed equidistant from the transmitter and receive
the ultra wide band wireless wave pulse; and distance-measuring equipment
which detects a distance or a direction to an object by measuring time
intervals between the first reception times when receivers receive the
ultra wide band wireless wave pulse directly from the transmitter and the
second reception times when the receivers receive a object-reflected wave
of the ultra wide band wireless wave pulse.