def test_freq_offset(self, fo):
snr = 37
ntaps = 17
sig = signals.SignalWithPilots(64, 2**16, 1024, 32, nframes=3, nmodes=2, fb=24e9)
sig2 = sig.resample(2*sig.fb, beta=0.01, renormalise=True)
sig3 = impairments.simulate_transmission(sig, snr, freq_off=fo)
sig4 = helpers.normalise_and_center(sig3)
sig4.sync2frame(corr_coarse_foe=False)
s1, s2 = equalisation.pilot_equalizer(sig4, [1e-3, 1e-3], ntaps, True, adaptive_stepsize=True, foe_comp=True)
d, ph = phaserec.pilot_cpe(s2, nframes=1)
assert np.mean(d.cal_ber()) < 1e-5
def test_cpe(self,lw):
snr = 37
ntaps = 17
sig = signals.SignalWithPilots(64, 2**16, 1024, 32, nframes=3, nmodes=2, fb=24e9)
sig2 = sig.resample(2*sig.fb, beta=0.01, renormalise=True)
sig2 = impairments.apply_phase_noise(sig2, 100e3)
sig3 = impairments.change_snr(sig2, snr)
sig4 = sig3[:, 20000:]
sig4.sync2frame(corr_coarse_foe=False)
s1, s2 = equalisation.pilot_equalizer(sig4, [1e-3, 1e-3], ntaps, True, adaptive_stepsize=True, foe_comp=False)
d, ph = phaserec.pilot_cpe(s2, nframes=1)
assert np.mean(d.cal_ber()) < 1e-5
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
def test_recovery_with_rotation(self, theta):
snr = 30.
ntaps = 17
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 = core.impairments.rotate_field(sig3, np.pi*theta)
sig4 = sig3[:, 20000:]
sig4.sync2frame(corr_coarse_foe=False)
s1, s2 = equalisation.pilot_equalizer(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()
assert np.mean(ser) < 1e-4
def run_pilot_receiver2(rec_signal,
process_frame_id=0,
foe_comp=True,
os=2,
M=128,
Numtaps=(17, 45),
frame_length=2**16,
method=('cma', 'cma'),
pilot_seq_len=512,
pilot_ins_ratio=32,
Niter=(10, 30),
mu=(1e-3, 1e-3),
adap_step=(True, True),
cpe_average=5,
use_cpe_pilot_ratio=1,
remove_inital_cpe_output=True,
remove_phase_pilots=True,
nframes=1):
rec_signal.sync2frame(Ntaps=Numtaps[0],
mu=mu[0],
method=method[0],
adaptive_stepsize=adap_step[0])
#shift_factor = pilotbased_receiver.correct_shifts(rec_signal.shiftfctrs, Numtaps, rec_signal.os)
#signal = np.roll(signal, -shift_factor[shift_factor>=0].min(), axis=-1)
#shift_factors -= shift_factors[shift_factors>=0].min()
#signal.shiftfctrs = shift_factors
taps_all, eq_mode_sig = pilot_equalizer(rec_signal,
mu,
Numtaps[1],
apply=True,
foe_comp=foe_comp,
adaptive_stepsize=adap_step[1],
Niter=Niter[1],
methods=method)
#symbs, trace = pilotbased_receiver.pilot_based_cpe(eq_mode_sig[:, eq_mode_sig._pilot_seq_len:eq_mode_sig.frame_len],
#eq_mode_sig.ph_pilots, eq_mode_sig._pilot_ins_rat,
#use_pilot_ratio=use_cpe_pilot_ratio, num_average=cpe_average,
#remove_phase_pilots=True)
symbs, trace = phaserec.pilot_cpe(eq_mode_sig,
N=cpe_average,
pilot_rat=use_cpe_pilot_ratio,
nframes=1,
use_seq=True)
#symbs = eq_mode_sig
return symbs, trace, eq_mode_sig, taps_all
sig2 = sig.resample(2 * sig.fb, beta=0.01, renormalise=True)
sig2 = impairments.apply_phase_noise(sig2, 100e3)
sig3 = impairments.change_snr(sig2, snr)
sig3 = core.impairments.rotate_field(sig3, np.pi / 0.1)
#sig4 = sig3[::-1, 20000:]
#sig4[0,:] = sig3[1,20000:]
#sig4[1,:] = sig3[0,20000:]
sig4 = sig3[:, 20000:]
#sig4 = impairments.apply_PMD(sig4, theta, dgd)
#sig4 = impairments.apply_PMD(sig4, theta, dgd)
#sig4[0,:] = sig3[1, 20000:]
#sig4[1,:] = sig3[0, 20000:]
sig4.sync2frame(Ntaps=ntaps)
wx, s1 = equalisation.pilot_equalizer(sig4, [1e-3, 1e-3],
ntaps,
True,
adaptive_stepsize=True)
s2, ph = phaserec.pilot_cpe(s1, nframes=1)
gmi = s2.cal_gmi()
evm = s2.cal_evm()
ber = s2.cal_ber()
ser = s2.cal_ser()
ksnr = s2.est_snr()
print("gmi {}".format(gmi))
print("ber {}".format(ber))
print("evm {}".format(evm))
print("snr {}".format(snr))
print("ser {}".format(ser))
plt.figure()
plt.subplot(121)
plt.title("Without CPE")