View Single Post
  #8   Report Post  
Old June 29th 09, 01:31 AM posted to sci.astro,rec.radio.amateur.space,rec.radio.amateur.antenna,sci.astro.seti,sci.physics
Robert Clark Robert Clark is offline
external usenet poster
 
First recorded activity by RadioBanter: Jun 2009
Posts: 8
Default High data rate space transmissions through visible lightcommunication.

On Jun 28, 1:41 pm, Richard Clark wrote:
On Sun, 28 Jun 2009 17:14:14 +1000, "Peter Webb"

wrote:
Furthermore, the radiation from a reflected area is isotropic - goes in all
directions - and hence very little is directed towards the earth.


Actually, it is lambertian in its distribution, and it would have a
major lobe that was directed in rather typical fashion (at the same,
but negative angle to the norm to the surface). However, as is the
intent of your response, very much less will find its way to the
intended target.

73's
Richard Clark, KB7QHC


This describes the reflection from the Iridium antennas as specular
where most of the reflected light is concentrated in a single
direction:

SeeSat-L Apr-98: Method for predicting flare.
http://satobs.org/seesat/Apr-1998/0175.html

About specular reflection:

Specular reflection.
http://en.wikipedia.org/wiki/Specular_reflection

We could get even higher concentration of the image by using
parabolic mirror reflectors.


Bob Clark