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RE: Future ECHO User Status burst?

Hi All,

A further variation:

When the voice uplink receiver ceases decoding valid CTCSS, a 9600bps packet
is transmitted on the voice downlink, that provides information on the
received uplink signal characteristics, as per approx 500ms ago.

Minimal received signal information would simply be the instantaneous RSSI
(in dBm) as at 500ms ago.

Ideally, an extended report could be issued, such as:

   dur min/avg/max/var = 4.5s -122/-106/-97/12

(The above report showing that valid CTCSS was detected for 4.5 seconds,
during which the minimum RSSI was -122dBm (ie fade to no signal), average
RSSI during the 4.5 seconds was -106dBm, and maximum RSSI was -97dBm.
During this time, the statistical variance was 12.4 (or this could be send
as the standard deviation, if square root is trivial on the IHU).

This would make ECHO an incredible flying test platform;  amateurs could,
for arguably the first time, directly quantify improvements to their
transmitting setup;  the transmission of statistical variance measured
throughout a transmission provides insights to the duration and depth of
fades related to polarisation mismatch (whether geometrical or Faraday
rotation induced) and nulls in antenna pattern.

Free text could be appended to the RSSI status data (as per Bob's initial


73 Chris vk6kch

p.s  The 500ms is to allow for the decay time of the CTCSS decoder;  make
sure we're giving information about the actual uplink transmission, and not
ambient noise after the RF has dropped, but CTCSS decode is still decaying.
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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