def test_apply_filter(dtype, benchmark):
fb = 40.e9
os = 2
fs = os * fb
N = 10**5
mu = 4e-4
theta = np.pi / 5.45
theta2 = np.pi / 4
t_pmd = 75e-12
M = 4
ntaps = 40
snr = 14
sig = signals.SignalQAMGrayCoded(M, N, fb=fb, nmodes=2, dtype=dtype)
S = sig.resample(fs, renormalise=True, beta=0.1)
S = impairments.change_snr(S, snr)
SS = impairments.apply_PMD(S, theta, t_pmd)
wxy, err = equalisation.equalise_signal(SS,
mu,
Ntaps=ntaps,
method="mcma",
adaptive_step=True)
E1 = equalisation.apply_filter(SS, wxy, method="pyx")
E2 = equalisation.apply_filter(SS, wxy, method="py")
E2 = E1.recreate_from_np_array(E2)
E1 = helpers.normalise_and_center(E1)
E2 = helpers.normalise_and_center(E2)
E1, ph = phaserec.viterbiviterbi(E1, 11)
E2, ph = phaserec.viterbiviterbi(E2, 11)
E1 = helpers.dump_edges(E1, 20)
E2 = helpers.dump_edges(E2, 20)
ser1 = E1.cal_ser().mean()
ser2 = E2.cal_ser().mean()
npt.assert_allclose(0, ser1, atol=3e-5)
npt.assert_allclose(0, ser2, atol=3e-5)
def test_normalise(nmodes):
s = signals.SignalQAMGrayCoded(64, 2**12, nmodes=nmodes)
s2 = helpers.normalise_and_center(s)
s3 = np.zeros(s.shape, dtype=s.dtype)
for i in range(nmodes):
s3[i] = helpers.normalise_and_center(s[i])
npt.assert_array_almost_equal(s2, s3)
def resample_poly(signal, fold, fnew, window=None, renormalise=False):
"""
Resamples a signal from an old frequency to a new. Preserves the whole data
but adjusts the length of the array in the process.
Parameters
----------
signal: array_like
signal to be resampled
fold : float
Sampling frequency of the signal
fnew : float
New desired sampling frequency.
window : array_like, optional
sampling windowing function
renormalise : bool, optional
whether to renormalise and recenter the signal to a power of 1.
Returns
-------
out : array_like
resampled signal of length fnew/fold*len(signal)
"""
signal = signal.flatten()
L = len(signal)
up, down = _resamplingfactors(fold, fnew)
if window is None:
sig_new = scisig.resample_poly(signal, up, down)
else:
sig_new = scisig.resample_poly(signal, up, down, window=window)
if renormalise:
p = np.mean(abs(signal)**2)
sig_new = normalise_and_center(sig_new) * np.sqrt(p)
return sig_new
def equalize_synchronize_signal(resampled_sig,
mu=None,
ntaps=None,
method=None,
adaptive_step=None,
avoid_cma_sing=None):
#Equalize and synchronize the signal and calculate the bit error rate
if mu is None:
mu = 2e-3
if ntaps is None:
ntaps = 21
if method is None:
method = "cma"
if adaptive_step is None:
adaptive_step = True
if avoid_cma_sing is None:
avoid_cma_sing = False
wxy, err = equalisation.equalise_signal(resampled_sig,
mu,
Ntaps=ntaps,
method=method,
adaptive_step=adaptive_step,
avoid_cma_sing=avoid_cma_sing)
E = equalisation.apply_filter(resampled_sig, wxy)
E = helpers.normalise_and_center(E)
ber, errs, tx_synced = E.cal_ber(
E, verbose=True
) #Synchronize the signal with the data and calculates the bit error rate
return E, ber, errs, tx_synced
def test_coarse_freq_offset(self, fo, mode_offset):
snr = 37
ntaps = 19
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(sig2,
snr,
freq_off=fo,
modal_delay=[0, mode_offset])
sig4 = helpers.normalise_and_center(sig3)
sig4 = sig4[:, 2000:]
sig4.sync2frame(corr_coarse_foe=True)
s1, s2 = equalisation.pilot_equaliser(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_apply_filter_benchmark(dtype, method, benchmark):
benchmark.group = "apply filter " + str(dtype)
fb = 40.e9
os = 2
fs = os * fb
N = 2**17
mu = 4e-4
theta = np.pi / 5.45
theta2 = np.pi / 4
t_pmd = 75e-12
M = 4
ntaps = 40
snr = 14
sig = signals.SignalQAMGrayCoded(M, N, fb=fb, nmodes=2, dtype=dtype)
S = sig.resample(fs, renormalise=True, beta=0.1)
SS = impairments.change_snr(S, snr)
#SS = impairments.apply_PMD(S, theta, t_pmd)
wxy, err = equalisation.equalise_signal(SS,
mu,
Ntaps=ntaps,
method="mcma",
adaptive_step=True)
E1 = benchmark(equalisation.apply_filter, SS, wxy, method)
E1 = helpers.normalise_and_center(E1)
ser = E1.cal_ser()
npt.assert_allclose(0, ser, atol=3e-5)
def test_pol_rot(self, method1, method2, phi):
phi = np.pi / phi
fb = 40.e9
os = 2
fs = os * fb
N = 2**16
beta = 0.9
mu1 = 0.1e-2
mu2 = 0.1e-2
M = 32
s = signals.SignalQAMGrayCoded(M, N, nmodes=2, fb=fb)
s = s.resample(fs, beta=beta, renormalise=True)
s = impairments.rotate_field(s, phi)
sout, wxy, err = equalisation.dual_mode_equalisation(
s, (mu1, mu2),
Ntaps=5,
Niter=(3, 3),
methods=(method1, method2),
adaptive_stepsize=(True, True))
sout = helpers.normalise_and_center(sout)
ser = sout.cal_ser()
#plt.plot(sout[0].real, sout[0].imag, 'r.')
#plt.plot(sout[1].real, sout[1].imag, 'b.')
#plt.show()
if ser.mean() > 0.5:
ser = sout[::-1].cal_ser()
npt.assert_allclose(ser, 0)
def test_pmd(self, method1, method2):
theta = np.pi / 5
dgd = 120e-12
fb = 40.e9
os = 2
fs = os * fb
N = 2**16
snr = 15
beta = 0.9
mu1 = 4e-4
mu2 = 4e-4
M = 32
ntaps = 21
s = signals.SignalQAMGrayCoded(M, N, nmodes=2, fb=fb)
s = s.resample(fs, beta=beta, renormalise=True)
s = impairments.apply_PMD(s, theta, dgd)
sout, wxy, err = equalisation.dual_mode_equalisation(
s, (mu1, mu2),
Ntaps=ntaps,
methods=(method1, method2),
adaptive_stepsize=(True, True))
sout = helpers.normalise_and_center(sout)
ser = sout.cal_ser()
if ser.mean() > 0.4:
ser = sout[::-1].cal_ser()
npt.assert_allclose(ser, 0,
atol=1.01 * 2 / N) # can tolerate 1-2 errors
def test_pmd_phase_fails(self, method, phi, dgd, lw):
theta = np.pi / phi
fb = 40.e9
os = 2
fs = os * fb
N = 2**16
snr = 15
beta = 0.3
mu = 2e-4
M = 4
ntaps = 15
s = signals.SignalQAMGrayCoded(M, N, nmodes=2, fb=fb)
s = s.resample(fs, beta=beta, renormalise=True)
s = impairments.apply_phase_noise(s, lw)
s = impairments.apply_PMD(s, theta, dgd)
wxy, err = equalisation.equalise_signal(s,
mu,
Ntaps=ntaps,
method=method,
adaptive_stepsize=False)
sout = equalisation.apply_filter(s, wxy)
sout, ph = phaserec.viterbiviterbi(sout, 11)
sout = helpers.normalise_and_center(sout)
sout = helpers.dump_edges(sout, 20)
ser = sout.cal_ser()
npt.assert_allclose(ser, 0)
def test_pmd_2(self, method, dgd):
phi = 6.5
theta = np.pi / phi
fb = 40.e9
os = 2
fs = os * fb
N = 2**16
snr = 15
beta = 0.1
mu = 0.9e-3
M = 4
ntaps = 7
s = signals.SignalQAMGrayCoded(M, N, nmodes=2, fb=fb)
s = s.resample(fs, beta=beta, renormalise=True)
s = impairments.apply_PMD(s, theta, dgd)
wxy, err = equalisation.equalise_signal(s,
mu,
Ntaps=ntaps,
method=method,
adaptive_stepsize=True,
avoid_cma_sing=True)
sout = equalisation.apply_filter(s, wxy)
sout = helpers.normalise_and_center(sout)
ser = sout.cal_ser()
npt.assert_allclose(ser, 0)
def test_pmd_phase(self, method1, method2, lw):
theta = np.pi / 4.5
dgd = 100e-12
fb = 40.e9
os = 2
fs = os * fb
N = 2**16
snr = 15
beta = 0.9
mu1 = 2e-3
if method2 == "mddma":
mu2 = 1.0e-3
else:
mu2 = 2e-3
M = 32
ntaps = 21
s = signals.SignalQAMGrayCoded(M, N, nmodes=2, fb=fb)
s = s.resample(fs, beta=beta, renormalise=True)
s = impairments.apply_phase_noise(s, lw)
s = impairments.apply_PMD(s, theta, dgd)
sout, wxy, err = equalisation.dual_mode_equalisation(
s, (mu1, mu2),
Ntaps=ntaps,
methods=(method1, method2),
adaptive_stepsize=(True, True))
sout, ph = phaserec.bps(sout, M, 21)
sout = helpers.normalise_and_center(sout)
sout = helpers.dump_edges(sout, 50)
ser = sout.cal_ser()
if ser.mean() > 0.4:
ser = sout[::-1].cal_ser()
npt.assert_allclose(ser, 0,
atol=1.01 * 3 / N) # Three wrong symbols is ok
def test_equalisation_prec(dtype, benchmark):
fb = 40.e9
os = 2
fs = os * fb
N = 10**5
#mu = np.float32(4e-4)
mu = 4e-4
theta = np.pi / 5.45
theta2 = np.pi / 4
t_pmd = 75e-12
M = 4
ntaps = 40
snr = 14
sig = signals.SignalQAMGrayCoded(M, N, fb=fb, nmodes=2, dtype=dtype)
S = sig.resample(fs, renormalise=True, beta=0.1)
S = impairments.apply_phase_noise(S, 100e3)
S = impairments.change_snr(S, snr)
SS = impairments.apply_PMD(S, theta, t_pmd)
wxy, err = benchmark(equalisation.equalise_signal,
SS,
mu,
Ntaps=ntaps,
method="mcma",
adaptive_stepsize=True)
E = equalisation.apply_filter(SS, wxy)
E = helpers.normalise_and_center(E)
E, ph = phaserec.viterbiviterbi(E, 11)
E = helpers.dump_edges(E, 20)
ser = E.cal_ser().mean()
npt.assert_allclose(0, ser, atol=3e-5)
def test_real_valued_single_mode(self, method):
s = signals.SignalQAMGrayCoded(4, 10**5, nmodes=1, fb=25e9)
s2 = s.resample(s.fb*2, beta=0.1)
s2 = impairments.sim_mod_response(s*0.2, dcbias=1.1)
s3 = helpers.normalise_and_center(s2)
s4 = impairments.change_snr(s3, 15)
s5, wx, err = equalisation.equalise_signal(s4, 1e-3, Ntaps=17, method=method, adaptive_stepsize=True, apply=True)
assert s5.cal_ser() < 1e5
def test_data_aided(self, modes, method, ps_sym):
from qampy import helpers
ntaps = 21
sig = signals.SignalQAMGrayCoded(64, 10**5, nmodes=2, fb=25e9)
sig2 = sig.resample(2*sig.fb, beta=0.02)
sig2 = helpers.normalise_and_center(sig2)
sig2 = np.roll(sig2, ntaps//2)
sig3 = impairments.simulate_transmission(sig2, dgd=150e-12, theta=np.pi/3., snr=35)
sig3 = helpers.normalise_and_center(sig3)
if ps_sym:
symbs = sig3.symbols
else:
symbs = None
sigout, wxy, err = equalisation.equalise_signal(sig3, 1e-3, Ntaps=ntaps, adaptive_stepsize=True,
symbols=symbs, apply=True, method=method, TrSyms=20000, modes=modes)
sigout = helpers.normalise_and_center(sigout)
gmi = np.mean(sigout.cal_gmi(llr_minmax=True)[0])
assert gmi > 5.9
def rrcos_resample(signal, fold, fnew, Ts=None, beta=None, taps=4001, renormalise=False, fftconv=True):
"""
Resample a signal using a root raised cosine filter. This performs pulse shaping and resampling a the same time.
The resampling is done by scipy.signal.resample_poly. This function can be quite slow.
Parameters
----------
signal : array_like
input time domain signal
fold : float
sampling frequency of the input signal
fnew : float
desired sampling frequency
Ts : float, optional
time width of the RRCOS filter (default:None makes this 1/fold)
beta : float, optional
filter roll off factor between (0,1] (default:None will use the default filter in poly_resample)
taps : int, optional
taps of the interpolation filter if taps is None we filter by zeroinsertion upsampling and multipling
with the full length rrcos frequency response in the spectral domain
fftconv : bool, optional
filter using zero insertion upsampling/decimation and filtering using fftconvolve. I often faster for
long filters and power of two signal lengths.
Returns
-------
sig_out : array_like
resampled output signal
"""
if beta is None:
return resample_poly(signal, fold, fnew)
assert 0 < beta <= 1, "beta needs to be in interval (0,1]"
if Ts is None:
Ts = 1/fold
up, down = _resamplingfactors(fold, fnew)
fup = up*fold
# for very large tap lengths it is better to filter with fftconvolve
# it could be better to use default values here, but this seems to depend on pc
if fftconv or taps is None:
sig_new = np.zeros((up*signal.size,), dtype=signal.dtype)
sig_new[::up] = signal
sig_new = rrcos_pulseshaping(sig_new, fup, Ts, beta, taps)
sig_new = sig_new[::down]
else:
t = np.linspace(0, taps, taps, endpoint=False)
t -= t[(t.size-1)//2]
t /= fup
nqf = rrcos_time(t, beta, Ts)
nqf /= nqf.max()
sig_new = scisig.resample_poly(signal, up, down, window=nqf)
if renormalise:
p = np.mean(abs(signal)**2)
sig_new = normalise_and_center(sig_new)*np.sqrt(p)
return sig_new
def load_symbols_from_matlab_file(fn,
M,
keys,
fb=10e9,
fake_polmux=False,
fake_pm_delay=0,
normalise=True,
**kwargs):
"""
Create a signal object from matlab file.
Parameters
----------
fn : basestring
Matlab filename
M : int
QAM order
keys: list
Nested list of keys (array names) in the matlab file. Depending on how the data is structured the keys can be in
one of the following formats:
If the symbols are given as a multi-dimensional array of complex numbers:
[[ keyname ]]
If the symbols are given as multi-dimensional real arrays pairs for real and imaginary part:
[[ key_real, key_imag ]]
If the different symbols of modes are saved in different complex arrays:
[[key_mode1], ..., [key_modeN]]
If the symbols are given as pairs of real arrays for each mode:
[[key_mode1_real, key_mode1_imag], ... [key_modeN_real, key_modeN_imag]]
fb: float, optional
Symbol rate
fake_polmux: boolean, optional
Whether the signal uses fake polmux, thus the single dimension matlab symbol array should be duplicated
fake_pm_delay: int, optional
Number of symbols to delay the second dimension in the fake pol-mux
normalise : boolean, optional
Normalise the symbols to an average power of 1 or not. Note that if you do not normalise you need to be very
careful with your signal metrics
kwargs: dict
Keyword arguments to pass to core.io.ndarray_from_matlab (see documentation for details)
Returns
-------
sig : signal_object
Signal generated from the loaded symbols
"""
symbs = ndarray_from_matlab(fn, keys, **kwargs)
if fake_polmux:
symbs = np.vstack([np.roll(symbs, fake_pm_delay), symbs])
if normalise:
symbs = helpers.normalise_and_center(symbs)
return signals.SignalQAMGrayCoded.from_symbol_array(symbs, M, fb)
def quantize_signal(sig, nbits=6, rescale=True, re_normalize=True):
"""
Function so simulate limited resultion using DACs and ADCs
Parameters:
sig: Input signal, numpy array
nbits: Quantization resultion
rescale: Rescale to range p/m 1, default True
re_normalize: Renormalize signal after quantization
Returns:
sig_out: Output quantized waveform
"""
# Create a 2D signal
sig = np.atleast_2d(sig)
npols = sig.shape[0]
# Rescale to
if rescale:
for pol in range(npols):
sig[pol] /= np.abs(sig[pol]).max()
levels = np.linspace(-1, 1, 2**(nbits))
sig_out = np.zeros(sig.shape, dtype=sig.dtype)
for pol in range(npols):
sig_quant_re = levels[np.digitize(sig[pol].real,
levels[:-1],
right=False)]
sig_quant_im = levels[np.digitize(sig[pol].imag,
levels[:-1],
right=False)]
sig_out[pol] = sig_quant_re + 1j * sig_quant_im
if not np.iscomplexobj(sig):
sig_out = sig_out.real
if re_normalize:
sig_out = normalise_and_center(sig_out)
return sig_out
Ncma = 10000
Nrde = N // 2 // os - int(1.5 * ntaps)
#S, symbols, bits = QAM.generate_signal(N, snr, baudrate=fb, samplingrate=fs, PRBSorder=(15,23))
sig = signals.SignalQAMGrayCoded(M, N, fb=fb, nmodes=2)
S = sig.resample(fs, beta=0.1, renormalise=True)
S = impairments.change_snr(S, snr)
SS = impairments.apply_PMD(S, theta, t_pmd)
E, wx, (err,
err_rde) = equalisation.dual_mode_equalisation(SS, (muCMA, muRDE),
ntaps,
methods=("mcma", "sbd"),
adaptive=(True, True))
E = helpers.normalise_and_center(E)
evm = E.cal_evm()
evm_s = S[:, ::2].cal_evm()
#sys.exit()
plt.figure()
plt.subplot(121)
plt.title('Recovered MCMA/MDDMA')
plt.plot(E[0].real, E[0].imag, 'r.', label=r"$EVM_x=%.1f\%%$" % (evm[0] * 100))
plt.plot(E[1].real, E[1].imag, 'g.', label=r"$EVM_y=%.1f\%%$" % (100 * evm[1]))
plt.legend()
plt.subplot(122)
plt.title('Original')
plt.plot(S[0, ::2].real,
S[0, ::2].imag,
'r.',
def test_normalise_and_center(self, nmodes):
s = signals.SignalQAMGrayCoded(64, 2**12, nmodes=nmodes)
s2 = helpers.normalise_and_center(s)
assert s.shape == s2.shape
def test_normalise_and_center(self):
s = signals.SignalQAMGrayCoded(64, 2**12)
s2 = helpers.normalise_and_center(s)
assert type(s) is type(s2)
evm1 = np.zeros(snr.shape)
evm_known = np.zeros(snr.shape)
i = 0
for sr in snr:
print("SNR = %2f.0 dB" % sr)
signal = signals.SignalQAMGrayCoded(M, N, nmodes=1, fb=fb)
signal = signal.resample(fnew=fs, beta=beta, renormalise=True)
signal_s = impairments.change_snr(signal, sr)
#signalx = np.atleast_2d(filtering.rrcos_pulseshaping(signal_s, beta))
wx, er = equalisation.equalise_signal(signal_s,
3e-4,
Ntaps=ntaps,
method="mcma",
adaptive_step=True)
signalafter = equalisation.apply_filter(signal_s, wx)
signalafter = helpers.normalise_and_center(signalafter)
evm1[i] = signal.cal_evm()[0]
evm_known[i] = signalafter.cal_evm()
# check to see that we can recovery timing delay
#signalafter = np.roll(signalafter * 1.j**np.random.randint(0,4), np.random.randint(4, 3000))
ser[i] = signalafter.cal_ser()
ber[i] = signalafter.cal_ber()
i += 1
ax1.plot(snrf,
theory.ber_vs_es_over_n0_qam(10**(snrf / 10), M),
color=c[j],
label="%d-QAM theory" % M)
ax1.plot(snr, ber, color=c[j], marker=s[j], lw=0, label="%d-QAM" % M)
ax2.plot(snrf,
theory.ser_vs_es_over_n0_qam(10**(snrf / 10), M),
color=c[j],
methods=("mcma", "sbd"),
adaptive_stepsize=(True, True))
E_s, wxy_s, (err_s, err_rde_s) = equalisation.dual_mode_equalisation(
SS, (muCMA, muRDE),
ntaps,
TrSyms=(Ncma, Nrde),
methods=("mcma", "sbd"),
adaptive_stepsize=(True, True))
E, wxy, (err, err_rde) = equalisation.dual_mode_equalisation(
SS, (muCMA, muRDE),
ntaps,
TrSyms=(Ncma, Nrde),
methods=("mcma", "mddma"),
adaptive_stepsize=(True, True))
E = helpers.normalise_and_center(E)
E_s = helpers.normalise_and_center(E_s)
E_m = helpers.normalise_and_center(E_m)
evm = sig[:, ::2].cal_evm()
evmE = E.cal_evm()
evmE_m = E_m.cal_evm()
evmE_s = E_s.cal_evm()
gmiE = E.cal_gmi()
print(gmiE)
plt.figure()
plt.subplot(241)
plt.title('Recovered MCMA/MDDMA')
plt.hexbin(E[0].real, E[0].imag, label=r"$EVM_x=%.1f\%%$" % (evmE[0] * 100))
plt.legend()
plt.subplot(242)
pilot_ins_ratio=sig_tx._pilot_ins_rat,
mu=(1e-3, 1e-3),
cpe_average=cpe_avg,
foe_comp=True)
# Calculate GMI and BER
#ber_res = np.zeros(npols)
#sout = signal.recreate_from_np_array(np.array(dsp_out[1]))
#for l in range(npols):
#gmi_res[l] = signal.cal_gmi(dsp_out[1][:])[0][0]
#ber_res[l] = signal.cal_ber(np.vstackdsp_out[1][l])
#gmi_res = sout.cal_gmi()[0]
#ber_res = sout.cal_ber()
#dsp_out0 = dsp_out
return dsp_out, dsp_out0, sig_tx, phase, phase0, signal, dsp_out2, dsp_out20, tall1, tall2
#return dsp_out, signal
if __name__ == "__main__":
#gmi, ber = sim_pilo print(methods)t_txrx(20)
dsp, dsp1, sig, ph, ph2, sign, sig2, sig3, t1, t2 = sim_pilot_txrx(
30, laser_lw=100e3, freq_off=50e6)
sigo = dsp
#sigo = sign.symbols.recreate_from_np_array(dsp)
sigo1 = sign.recreate_from_np_array(dsp1)
sigo = helpers.normalise_and_center(sigo)
sigo1 = helpers.normalise_and_center(sigo1)
print(sigo.cal_gmi())
print(sigo1.cal_gmi(signal_rx=sigo1))
def sim_tx(frame,
os,
num_frames=5,
modal_delay=None,
beta=0.1,
snr=None,
symb_rate=24e9,
freqoff=None,
linewidth=None,
rot_angle=None,
resBits_tx=None,
resBits_rx=None):
"""
Function to simulate transmission distortions to pilot frame
"""
npols = frame.shape[0]
#sig = np.zeros([npols, int(num_frames*(frame[0, :]).shape[0] * os)], dtype=complex)
sig = frame
for l in range(npols):
#curr_frame = np.tile(frame[l, :],num_frames)
# Add modal delays, this can be used to emulate things like fake-pol. mux. when the frames are not aligned.
if modal_delay is not None:
if np.array(modal_delay).shape[0] != npols:
raise ValueError(
"Number of rolls has to match number of modes!")
sig = np.roll(sig, modal_delay[l])
# Upsample and pulse shaping
#if os > 1:
# sig[l, :] = resample.rrcos_resample(curr_frame, 1, os, beta=beta, renormalise=True)
# DAC
if resBits_tx is not None:
sig[l, :] = impairments.quantize_signal(sig[l, :],
nbits=resBits_tx)
# Add AWGN
if snr is not None:
sig[l, :] = impairments.add_awgn(sig[l, :],
10**(-snr / 20) * np.sqrt(os))
# Add FOE
if freqoff is not None:
sig[l, :] *= np.exp(2.j * np.pi * np.arange(len(sig[l, :])) *
freqoff / (symb_rate * os))
# Add Phase Noise
if linewidth is not None:
sig[l, :] = impairments.apply_phase_noise(sig[l, :], linewidth,
symb_rate * os)
# Verfy normalization
sig = helpers.normalise_and_center(sig)
# Currently only implemented for DP signals.
if (npols == 2) and (rot_angle is not None):
sig = utils.rotate_field(sig, rot_angle)
if resBits_rx is not None:
for l in range(npols):
sig[l, :] = impairments.quantize_signal(sig[l, :],
nbits=resBits_rx)
return sig
muRDE = 6e-4
Ncma = 100000
Nrde = 300000
ntaps = 51
niter = 1
symbs = io.load_symbols_from_matlab_file(
"data/20GBaud_SRRC0P05_64QAM_PRBS15.mat",
64, (("X_Symbs", ), ),
fb=20e9,
normalise=True,
fake_polmux=True)
sig = io.create_signal_from_matlab(
symbs, "data/OSNRLoading_IdealRxLaser_1544p91_Att_1_OSNR_38_1.mat", 50e9,
(("CH1", "CH2"), ("CH3", "CH4")))
sig = sig[:, :10**6]
sig = helpers.normalise_and_center(sig)
sig = sig.resample(2 * symbs.fb, beta=0.05, renormalise=True)
#sig = analog_frontend.comp_IQ_inbalance(sig)
E, wxy, err_both = equalisation.dual_mode_equalisation(
sig, (muCMA, muRDE),
ntaps,
Niter=(niter, niter),
methods=("mcma", "sbd"),
adaptive_stepsize=(True, True))
#E, wxy, err = equalisation.equalise_signal(sig, muCMA, Ntaps=33, apply=True)
E = helpers.normalise_and_center(E)
gmi = E.cal_gmi()
print(gmi)
#sys.exit()