def test_add_modal_delay(self, dtype):
s = signals.SignalQAMGrayCoded(16,
2**16,
fb=10e9,
nmodes=2,
dtype=dtype)
s2 = cimpairments.add_modal_delay(s, [0, 1000])
assert s.dtype == s2.dtype
def simulate_transmission(sig,
snr=None,
freq_off=None,
lwdth=None,
dgd=None,
theta=np.pi / 3.731,
modal_delay=None,
dispersion=None,
roll_frame_sync=False):
"""
Convenience function to simulate impairments on signal at once
Parameters
----------
sig : array_like
input signal
snr : flaat, optional
desired signal-to-noise ratio of the signal. (default: None, don't change SNR)
freq_off : float, optional
apply a carrier offset to signal (default: None, don't apply offset)
lwdth : float
linewidth of the transmitter and LO lasers (default: None, infinite linewidth)
dgd : float
first-order PMD (differential group delay) (default: None, do not apply PMD)
theta : float
rotation angle to principle states of polarization
modal_delay : array_like, optional
add a delay given in N samples to the signal (default: None, do not add delay)
dispersion: float, optional
dispersion in s/m
Returns
-------
signal : array_like
signal with transmission impairments applied
"""
if roll_frame_sync:
if not (sig.nframes > 1):
warnings.warn(
"Only single frame present, discontinuity introduced")
sig = np.roll(sig, sig.pilots.shape[1], axis=-1)
if lwdth is not None:
sig = apply_phase_noise(sig, lwdth)
if freq_off is not None:
sig = add_carrier_offset(sig, freq_off)
if snr is not None:
sig = change_snr(sig, snr)
if modal_delay is not None:
sig = add_modal_delay(sig, modal_delay)
if dispersion is not None:
sig = add_dispersion(sig, D, 1)
if dgd is not None:
sig = apply_PMD(sig, theta, dgd)
return sig
def simulate_transmission(sig, snr=None, freq_off=None, lwdth=None, dgd=None, theta=np.pi/3.731, modal_delay=None):
"""
Convenience function to simulate impairments on signal at once
Parameters
----------
sig : array_like
input signal
snr : flaat, optional
desired signal-to-noise ratio of the signal. (default: None, don't change SNR)
freq_off : float, optional
apply a carrier offset to signal (default: None, don't apply offset)
lwdth : float
linewidth of the transmitter and LO lasers (default: None, infinite linewidth)
dgd : float
first-order PMD (differential group delay) (default: None, do not apply PMD)
theta : float
rotation angle to principle states of polarization
modal_delay : array_like, optional
add a delay given in N samples to the signal (default: None, do not add delay)
Returns
-------
signal : array_like
signal with transmission impairments applied
"""
if lwdth is not None:
sig = apply_phase_noise(sig, lwdth)
if freq_off is not None:
sig = add_carrier_offset(sig, freq_off)
if snr is not None:
sig = change_snr(sig, snr)
if modal_delay is not None:
sig = add_modal_delay(sig, modal_delay)
if dgd is not None:
sig = apply_PMD(sig, theta, dgd)
return sig