Back to my blog, I have been away working on things!
I have been reading
"Turbo Coding, Turbo Equalisation and Space-Time
Coding." ISBN 0-470-84726-3
I managed to generate a C++ class for the RSC Turbo
code they analyse in the book and pretty impressive
it is too. I am thinking of using it in a future Hybrid
ARQ mode for HF.
In the mean time I have written a simple keyboard
to keyboard FEC mode. It uses 8 FSK, BCH(15,7,5)
FEC (with soft decision decoding) and 128 ms symbol
periods. The occupied bandwidth is about 75 Hz.
So far I have tested it with Gaussian noise but
I am hoping to try it out on HF in the next few days
when I have selected someone to try it with.
I have downloaded the forms to re-apply for a 5 MHz NoV.
I know the 5 MHz allocation will not last much longer but
it is a useful band to have for inter G testing. I used it for
digital voice testing a few years ago with Andy G4JNT.
I will post again when I have some results to share about the
new mode (that has no name yet).