Engineers
from Pennsylvania State University's Center for Information
and Communications Technology Research have demonstrated a
system for use in indoor local area communication networks.
Using a non-line-of-sight IR wireless broadband
transmissions system, the team claims the technology offers
low power and a reduced error rate.
The system uses a link design consisting of a multi-beam
transmitter with a narrow field of view receiver, which
filters out noise. It has a bit error rate of one error per
billion bits at bit rates up to a few hundred megabits per
second, and it operates at milliwatt transmitted power levels.
Dr Mohsen Kavehrad, professor of electrical engineering at
Penn State University, said: "This error rate is unmatched
considering the offered transmission capacity."
To form a lan for a group of machines, each machine is
equipped with a low-power IR source and a holographic beam
splitter.
A low-power beam is separated into several narrow beams,
which strike the ceiling and walls to form an invisible grid
encompassing the whole room. The beams are reflected at the
strike points so they can be used to send and receive
information.
