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gistfile1.c

#define TAU_CROSSOVER 0.5
#define TAU_BIAS (TAU_CROSSOVER*10)
#define A (1e-3/TAU_CROSSOVER)
#define B (1e-3/TAU_BIAS)

double dll_update = chan->dll_pgain*(chan->dll_disc-dll_disc_prev) + chan->dll_igain*chan->dll_disc;
double pll_update = (1.023e6/L1_HZ)*(chan->pll_pgain*(chan->pll_disc-pll_disc_prev) + chan->pll_igain*chan->pll_disc);

// Original:

chan->code_phase_rate += dll_update;

// Ours:

chan->code_phase_rate += pll_update + A*(dll_update - chan->code_phase_rate);

// I think it should be (maybe):

chan->code_phase_rate += pll_update + A*dll_update;