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Confusion over AO-40 and 2.4 GHz devices



Hello all,
	
	I'm confused as to the status of AO-40 and the 2.4 GHz devices
that are commonly available in consumer electronics.  I understand that
the design of much of the satellite was done quite awhile ago, but by
the time it was launched, it should have been obvious that there was
going to be a great deal of noise on the 2.4 GHz band due to ISM
devices.  Obviously a downlink in the middle of this band was going to
suffer consequences due to co-channel interference.
	With this in mind, I thought that DSP boards onboard AO-40 are
supposed to allow downlink modes with custom modems, so something like a
relatively wideband signal with lots of FEC could allow you generate
enough process gain to punch through the noise generated by spread
spectrum ISM devices.  These sorts of techniques have been used in HF
for quite awhile now.  I haven't run the numbers for the average
interference scenario, but it seems that using an antenna with high
directivity one should be able to avoid most of the local noise.  
	What is the status of using the digital modes on AO-40?
According to the AMSAT-DL webpage, it looks like the RUDAK units are
still undergoing commissioning.  I understand that the unknown event
that occurred after launch has put the craft in an uncertain situation,
but it seems to me with the various reports of interference from 2.4 GHz
devices and the radars that are coming up and down on the U an L band
uplinks, I would assume a very high priority would be to put together
method of communicating via some sort of data mode.  Is such a mode even
possible on AO-40?  I'm thinking along the lines of the article proposed
by Phil Karn on his website http://people.qualcomm.com/karn/jjsat/ for
Amsat's next satellite.  Could a partial implementation of his ideas be
accomplished on AO-40, assuming RUDAK-1 and 2 come up okay?

73's
Dave,

W9OFA

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