Starting from the recorded WAV file in I/Q mode, all processing (symbol synchronization, doppler correction, symbol analysis, plotting) was done manually in GNU Octave using signal-analysis for LFSR-detection.
The bursts consist of a BPSK-modulated preamble which is a subsequence of a length-14 LFSR with period 214-1, i.e., a maximal length LFSR. The preamble is followed by 6 720-symbol-long frames, where each frame starts with 72 known 8PSK-modulated symbols, followed by 72 BPSK-modulated unknown symbols and 576 8PSK unknown symbols.
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| Preamble and frame structure |
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| 720 symbol frames |
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