With
the improvements in semiconductors optical free space communication has become
n attractive alternative to existing signal conducts as fibre or wireless (RF).
It offers high data rates and is much less expensive than underground fibre. But
there are a few restrictions, which may mean it remains an alternative. Many engineers
are familiar with one of two successful existing technologies for data communication:
(1) Guided wave (e.g. fibre optics) and (2) wireless free space communication
(e.g. RF). Fibre optics offers extremely high bandwidths for high data rate, while
RF communications offers the advantage of wireless connectivity and the ability
to broadcast over a wide area. Optical free space communication fits into the
2nd group, but has some properties of the 1st. Many aspects are related to fibre
optics with the difference, that the media is air and not fibers. Therefore are
the required devices similar to those used with fibers.
The
advantages of such a system are the following:
_ No need for digging up the
roads
_ No radio frequency licenses are required
_ Bandwidth is equal or
superior to fibre systems and much better than RF
_ Doesn't cause interference
with existing electromagnetic equipment because interference on narrow band point-to-point
connections is rather unlikely.
