> From: Mik O Kim <Mik.O.Kim@NPBSMTP1.NB.ROCKWELL.COM>
>
> Ack!!! CDMA!
>
> How did you manage to keep other transmitters from emitting too strongly? I
> suspect that strong emissions could overwelm the reception.
>
> > I have actually used something similar to your suggestion, but in the
> > field of IR communication.  In this case the transmitter sent out a
> > 32-bit pattern (4 of the bits being '1', the rest zero) repetitively.
> > The receiver could tune into the pattern being transmitted, even if other
> > transmitters were in the vicinity (so long as the other transmitters
> > used a different 32-bit code).
>

All transmitters work at the same output level, with unique codes.  The
receiver unit is rather directional, so it locks on to the transmitter
towards which it points (which will be received with the greatest signal
strength).  The received signal from the IR detector is digitised to
a 0-255 level, not a threshold detector or comparator.  It can thus
pick out the strongest signal with a bit of help from a correlation
algorithm.

The only purpose of this system is that the receiver knows which
transmitter it is physically pointing at.  There is no other data
transfer from Tx to Rx.

Regards,
SJH
Canberra, Australia