def test_recovery_with_pmd(self, theta, dgd):
snr = 30.
ntaps = 41
sig = signals.SignalWithPilots(64,
2**16,
1024,
32,
nframes=3,
nmodes=2,
fb=24e9)
sig2 = sig.resample(2 * sig.fb, beta=0.1, renormalise=True)
sig3 = impairments.change_snr(sig2, snr)
sig3 = impairments.apply_PMD(sig3, theta * np.pi, dgd)
sig4 = sig3[:, 20000:]
sig4.sync2frame(corr_coarse_foe=False)
s1, s2 = equalisation.pilot_equaliser(sig4, [5e-3, 5e-3],
ntaps,
True,
adaptive_stepsize=True,
foe_comp=False)
ph = phaserec.find_pilot_const_phase(
s2.extract_pilots()[:, :s2._pilot_seq_len], s2.pilot_seq)
s2 = phaserec.correct_pilot_const_phase(s2, ph)
ser = s2.cal_ser(synced=False)
snr_m = s2.est_snr(synced=False)
snr_db = 10 * np.log10(np.mean(snr_m))
assert np.mean(ser) < 1e-4
def test_swap_pols(self):
snr = 30.
sig = signals.SignalWithPilots(64, 2**16, 1024, 32, nframes=3, nmodes=2, fb=24e9)
sig2 = sig.resample(2*sig.fb, beta=0.1, renormalise=True)
sig2 = impairments.change_snr(sig2, snr)
sig3 = sig2[::-1]
sig4 = sig3[:, 20000:]
sig4.sync2frame(corr_coarse_foe=False)
s1, s2 = equalisation.pilot_equalizer(sig4, [1e-3, 1e-3], 17, True, adaptive_stepsize=True, foe_comp=False)
ph = phaserec.find_pilot_const_phase(s2.extract_pilots()[:,:s2._pilot_seq_len], s2.pilot_seq)
s2 = phaserec.correct_pilot_const_phase(s2, ph)
ser = s2.cal_ser(synced=True)
assert np.mean(ser) < 1e-4