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peterantypas / maiana

MAIANA™ is the first Open Source AIS transponder. It proudly raises an extra long middle finger to the marine electronics industry, government overregulation and everything else that gets in the way of innovation in this space.
GNU General Public License v3.0
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AIS preamble #9

Closed SamSamKhan closed 4 years ago

SamSamKhan commented 6 years ago

Dear Peter, You have set the PREAMBLE_CONFIG to 0x21 in radio_config_ph.h file which put the si446x to standard preamble mode. whereas the AIS standard requires NRZI coding which led to non standard preamble pattern. could you please explain why? thanks in advance, Saman

peterantypas commented 6 years ago

To the best of my recollection it didn't matter. The SYNC WORD is what the receiver keyed on, and that's set for the NRZI-encoded preamble: 001100110011, etc.