Auto tracking?
The issue of maintaining accurate targeting of a Free-space Optics beam is something a lot of people have trouble with. But, think of it this way: you're standing outside in the dark with a laser pointer trying to hold it steady on a white building a block away. You "think" you're doing OK, but your helper next to the building says, "Hold it still, it's jumping all over the place."
The problem of coarse is that when you "wiggle" the pointer by a mere tenth of a degree (very little, approximately 2 mrad...mrad is the measure most commonly used to specify FSO beam divergence rates) you have exceeded the wiggle tolerance of 3/4ths of all non-active aligned FSO links.
"Well, just bolt the transceiver down tight, you say."
OK. But what if the building moves either through sway or more commonly as a result of thermal dimensional distortions that are solar diurnal events.
Now we're not saying it is impossible to keep the beam on target. In fact, we have experience with it...about a hundred or so static first generation design links deployed so far. But it is a critical issue that MUST be very carefully dealt with when deploying non-active aligned links, and one that goes largely away with active aligned links.
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What's HOT, what's not...
Auto tracking? >>
Single vs. multiple beams? >>
Hybrid FSO + RF? >>
850nm vs. 1550nm? >>
Passive vs. Active? >>
Wikipedia on FSO >>
FSO vs. RF? >>
Security? >>
Eye Safety >>
Tell me more!
>>
Where does Free-space Optics fit best? >>
Where does Free-space Optics not fit? >>
Competitive comparison of the major Free-Space Optics solutions. >>
Free-Space Optics White Papers. >>
Who are we, and what’s our motivation for supporting this web site? >>
And last but not least…here’s our Free-Space Optics commercial website for specific product and/or service inquiries. >>
...and our refurbished FSO equipment site. >>