Applying small adjustments to time (+0.05 s) and frequency (-100 uHz) was
able to achieve much better decode of the same transmission. A lot of
trial and error!
Hello
Rob,
My congrats to your first EbNaut decode! And even quite a distance:
http://k7fry.com/grid/?qth=FM18QI&from=jn49ik00It
is interesting that you captured such an early transmission.
As mentioned,
it is worth to play with small time offsets of +- 5%, 10%, 15% of a symbol
length to see what the maximum SNR will be. Even applying a small frequency
offset can help. My Tx frequency is accurate but as you see, your phase pattern
is turning by -60 deg (180,150,150,120) during the transmission time. So this is
-1/6 cycle in 1536 seconds, or -109 uHz. EbNaut can compensate up to 90 deg
phase drift i think. So, if there is no decode or just rubbish, it can help to
apply a small frequency offset and try again...
73, Stefan
