[Laser] 5 mw laser transceiver kit

[Chuck Hast]

On Mon, Sep 20, 2010 at 22:19, Chris L <vocalion1928 at hotmail.com> wrote:
>
> I have just one question.
>
> When atmospheric physics dictates that spatial coherence (ie laser light) is a hindrance to scintillation-free communications; when the reliability, ruggedness, safety, cheapness, and measurements taken on the validity of LED-Fresnel combination are proven by a series of world DX records in Australia and America; when ARRL rules have been changed changed to suit those measured results; while lasers are costly devices demanding even more costly collimating optics, and when many governments are imposing bans on the outdoor usage of laser pointer devices...
>
> ...why do people persist with lasers for atmospheric optical communication?
Probably for the same reason they climb mountains, toss rocks at
hornet nest, drive way over
the speed limit even on roads that are definitely not for it.

I think that the laser gives it a gee whiz bang view, you can blow
smoke at the beam
and it looks very impressive, usually the LED beam is broad and harder
to show, but
that is where it's value is. There are those who are actually doing
interesting work with
atmospheric FSO links, but it is I guess complicated.

Here are some interesting documents done by the US Navy at the NRL This one
describes the facility:
www.nrl.navy.mil/fpco/pubs/05-1226-2651.pdf

This one deals with: (hey it is the Navy!)
Packet testing in free-space optical communication links over water
www.nrl.navy.mil/fpco/pubs/06-1226-1306.pdf

And this one goes into the issue of
Large Diameter, High Speed InGaAs Receivers for Free-Space Lasercom
www.nrl.navy.mil/fpco/pubs/07-1226-0924.pdf