#pragma once #include namespace ft8 { struct MagArray { int num_blocks; // number of total blocks (symbols) int num_bins; // number of FFT bins int time_osr; // number of time subdivisions int freq_osr; // number of frequency subdivisions uint8_t * mag; // FFT magnitudes as [blocks][time_sub][freq_sub][num_bins] }; struct Candidate { int16_t score; int16_t time_offset; int16_t freq_offset; uint8_t time_sub; uint8_t freq_sub; }; // Localize top N candidates in frequency and time according to their sync strength (looking at Costas symbols) // We treat and organize the candidate list as a min-heap (empty initially). int find_sync(const MagArray * power, const uint8_t *sync_map, int num_candidates, Candidate *heap); // Compute log likelihood log(p(1) / p(0)) of 174 message bits // for later use in soft-decision LDPC decoding void extract_likelihood(const MagArray *power, const Candidate & cand, const uint8_t *code_map, float *log174); }