|
|
 |
|
Optical Wireless
Technology
Characteristics
- Traditional
physics divides electromagnetic waves in three or four different categories - starting
with audio at very low end of the frequency range (kilohertz), then radio
waves (from MHz to GHz), then visible light and finally infrared. Radio waves
extend up to 100 GHz range. After that, you get into visible light and then
infrared. As the frquency increases, the width of the wave decreases.
- Optical
wireless is where traditional radio waves end and visible light starts.
- This
is generally
in 100 GHz in frequency range or in millimeter
wave length
- Optical
wireless is in the spectrum range where radio waves end and enter into
visible light band
- Some
vendors are starting
in the 60 GHz (www.hxi.com) frequency range; other vendors (www.endwave.com) are
experimenting in 94
GHz, 140 GHz and 220 GHz.
- Could
reach theoretical speeds of 100 Gbit/sec in future - practical limit in 2001
was 622 Mbps as quoted by Endwave.
- Currently,
this spectrum band is not licensed - FCC and other regulatory agencies are
not sure how to deal with it. In some cases, military might be using
it.
- Vendors in this space - Harmonix (www.hxi.com), Endwave (www.endwave.com)
and www.Optel-communication.com
(of Germany)l
-
|
|
