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<DIV><FONT face=Arial size=2>MIMO and FSO? ehm...
noooo.</FONT></DIV>
<DIV><FONT face=Arial size=2>This is only for RF with COFDM and guard interval
pilots.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Martin</FONT></DIV>
<DIV> </DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=pkyaduvanshi@gmail.com href="mailto:pkyaduvanshi@gmail.com">PRAMOD
YADUVANSHI</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=ronja@lists.pointless.net
href="mailto:ronja@lists.pointless.net">Twibright Ronja</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, September 20, 2008 8:25
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [Ronja] Multiple receivers
and transmitters</DIV>
<DIV><BR></DIV>
<DIV dir=ltr>I feel for a laser based link MIMO will be a better option to
improve SNR but for LED based Tx/Rx scintillation effects will be almost
negligible and MIMO will hardly help. <BR><BR>
<DIV class=gmail_quote>2008/9/20 Gregory Maxwell <SPAN dir=ltr><<A
href="mailto:gmaxwell@gmail.com">gmaxwell@gmail.com</A>></SPAN><BR>
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<DIV class=Ih2E3d>On Sat, Sep 20, 2008 at 1:09 PM, J.D. Bakker <<A
href="mailto:jdb@lartmaker.nl">jdb@lartmaker.nl</A>> wrote:<BR>>>I
have been thinking how to divide multiple heads between
receivers<BR>>>and transmitters optimally, i. e. if we want to build N
heads, how<BR>>>to get the maximum range.<BR>><BR>> Given N
transmitters and M receivers, it might be better (but more<BR>>
complicated) to apply MIMO techniques.<BR><BR><BR></DIV>In radio the problem
that MMIO solves is multipath: Between your TX<BR>and RX there are
obstructions which alter the signal, they shift<BR>phase in a frequency
dependent manner, and creates nulls and peaks.<BR>MMIO uses spatially
separated antenna which get different views of the<BR>multi-path
environment. You can then define a collection of filters<BR>which take
advantage of the multipath to form separate channels and<BR>gain
capacity.<BR><BR>For a fairly slowly amplitude modulated optical path like
RONJA I<BR>would not expect there to be significant multipath. I do not
believe<BR>MMIO would help. But MMIO systems typically use efficient
modulation<BR>systems which would probably help ronja very much, but
supporting<BR>them would be very costly.<BR><BR>Karel where does the noise
come from in the receive head are we<BR>talking about optical background
noise which would increase with<BR>increased collection area or is it
primarily noise from the<BR>photodetector and amplifier? If it is
primary electronic noise,<BR>creating a larger passive collector may allow
you to increase receiver<BR>area without seeing much of a nosie
increase.<BR><BR>So long as your transmitter area is strictly smaller than
the<BR>reciever's field of view, however, you would always be as well
or<BR>better off to increase the transmitter area. though perhaps you
may<BR>wish to make the receiver more selective (for example, by placing
it<BR>at the back of a long black tube).<BR>
<DIV>
<DIV></DIV>
<DIV class=Wj3C7c><BR>--<BR>Twibright Ronja mailing list <A
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target=_blank>http://pointless.net/mailman/listinfo/ronja</A><BR></DIV></DIV></BLOCKQUOTE></DIV><BR></DIV>
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<P></P>-- <BR>Twibright Ronja mailing list
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