PairingWindow

The pairing interval, the phase drift it must survive, and the trade between

5/5 passed in 1ms

Test	What it does	Result
test_drift_endpoints	A still reference returns the optical misalignment itself, a perfect interferometer the drift alone, and the two add. Neither paper prints the composition; both endpoints are theirs.	✅ pass
test_drift_wraps	Past pi the error rate saturates at a half while the raw phase keeps rising past 1000 rad.	✅ pass
test_fibre_drift	Xie's phase-tracking-free case, 8 rad/ms at 402 km over 50 us on a 1 GHz system: 0.2 rad of excursion and 0.0099667 of error, against his about 1%.	✅ pass
test_interval_costs	The interference error is 0.0002467, 0.0244717 and 0.2061074 over 1, 10 and 30 us on a 4 GHz system at 10 kHz.	✅ pass
test_laser_drift	Xie's case with neither tracking nor locking, 100 kHz over 1 us on a 10 GHz system: pi/10 and 2.447% of error, against the 2.4% he prints.	✅ pass