Files
ewsdr/fectest.lpr
T
ew8bakandClaude Opus 4.8 afc8775ddb feat: QO-100 beacon AO-40 FEC decode end-to-end (Milestone 2)
Full chain now decodes the QO-100 central beacon to 256-byte AO-40 frames
on-air (frames>0, RS errors=0). Builds on M1 (stable BPSK demod).

FEC backend (BeaconFEC.pas, TBeaconFEC):
- AO-40 FEC: distributed sync (65 bit, step 80) -> 80x65 deinterleave ->
  Viterbi r=1/2 k=7 -> CCSDS descramble -> 2x RS(160,128). Links system
  libfec (Karn) load-time (libfec.so/.dll/.dylib). Viterbi AO-40 [0x4F,-0x6D]
  remapped to libfec [0x6D,0x4F]. Validated against gr-satellites reference
  vectors (fectest2: exact 256-byte frame, 0 mismatches).

DBPSK Manchester frontend (BeaconDecoder.pas):
- Chip-rate (800) processing: RRC matched filter -> ML signal-times-slope
  timing recovery -> Costas -> Manchester combine (block phase select) ->
  differential decode -> soft symbols to FEC.
- Carrier acquisition: squaring-FFT estimates the residual (carrier at +-pi/chip
  defeats decision-directed Costas), one-shot pulls it to DC via residual NCO.
- Costas frequency offload into pre-RRC NCO (with deadband) tracks LNB drift
  without hitting the +-pi Costas clamp.
- ML TED replaces Gardner, which degenerates on the Manchester chip stream.

Temporary on-air diagnostics retained (IQ dump + STATE log) pending wider
signal validation; to be removed before final cleanup.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-22 10:21:33 +03:00

19 lines
335 B
ObjectPascal

program fectest;
{$MODE Delphi}
uses SysUtils, BeaconFEC;
var
fec: TBeaconFEC;
msg: string;
ok: Boolean;
begin
fec := TBeaconFEC.Create;
try
ok := fec.SelfTest(msg);
WriteLn('SelfTest: ', msg);
if ok then WriteLn('==> PASS') else WriteLn('==> FAIL');
finally
fec.Free;
end;
if not ok then Halt(1);
end.