def build_network(network, equipment, pref_ch_db, pref_total_db):
default_span_data = equipment['Span']['default']
max_length = int(convert_length(default_span_data.max_length, default_span_data.length_units))
min_length = max(int(default_span_data.padding / 0.2 * 1e3), 50_000)
bounds = range(min_length, max_length)
target_length = max(min_length, 90_000)
# set roadm loss for gain_mode before to build network
fibers = [f for f in network.nodes() if isinstance(f, elements.Fiber)]
add_connector_loss(network, fibers, default_span_data.con_in, default_span_data.con_out, default_span_data.EOL)
add_fiber_padding(network, fibers, default_span_data.padding)
# don't group split fiber and add amp in the same loop
# =>for code clarity (at the expense of speed):
for fiber in fibers:
split_fiber(network, fiber, bounds, target_length, equipment)
amplified_nodes = [n for n in network.nodes() if isinstance(n, elements.Fiber) or isinstance(n, elements.Roadm)]
for node in amplified_nodes:
add_egress_amplifier(network, node)
roadms = [r for r in amplified_nodes if isinstance(r, elements.Roadm)]
for roadm in roadms:
set_egress_amplifier(network, roadm, equipment, pref_ch_db, pref_total_db)
trx = [t for t in network.nodes() if isinstance(t, elements.Transceiver)]
for t in trx:
next_node = next(network.successors(t), None)
if next_node and not isinstance(next_node, elements.Roadm):
set_egress_amplifier(network, t, equipment, 0, pref_total_db)
def __init__(self, **kwargs):
try:
self._length = convert_length(kwargs['length'],
kwargs['length_units'])
# fixed attenuator for padding
self._att_in = kwargs['att_in'] if 'att_in' in kwargs else 0
# if not defined in the network json connector loss in/out
# the None value will be updated in network.py[build_network]
# with default values from eqpt_config.json[Spans]
self._con_in = kwargs['con_in'] if 'con_in' in kwargs else None
self._con_out = kwargs['con_out'] if 'con_out' in kwargs else None
if 'ref_wavelength' in kwargs:
self._ref_wavelength = kwargs['ref_wavelength']
self._ref_frequency = c / self.ref_wavelength
elif 'ref_frequency' in kwargs:
self._ref_frequency = kwargs['ref_frequency']
self._ref_wavelength = c / self.ref_frequency
else:
self._ref_wavelength = 1550e-9
self._ref_frequency = c / self.ref_wavelength
self._dispersion = kwargs['dispersion'] # s/m/m
self._dispersion_slope = kwargs['dispersion_slope'] if 'dispersion_slope' in kwargs else \
-2 * self._dispersion/self.ref_wavelength # s/m/m/m
self._beta2 = -(self.ref_wavelength**2) * self.dispersion / (
2 * pi * c) # 1/(m * Hz^2)
# Eq. (3.23) in Abramczyk, Halina. "Dispersion phenomena in optical fibers." Virtual European University
# on Lasers. Available online: http://mitr.p.lodz.pl/evu/lectures/Abramczyk3.pdf
# (accessed on 25 March 2018) (2005).
self._beta3 = (
(self.dispersion_slope -
(4 * pi * c / self.ref_wavelength**3) * self.beta2) /
(2 * pi * c / self.ref_wavelength**2)**2)
self._gamma = kwargs['gamma'] # 1/W/m
self._pmd_coef = kwargs['pmd_coef'] # s/sqrt(m)
if type(kwargs['loss_coef']) == dict:
self._loss_coef = squeeze(
kwargs['loss_coef']
['loss_coef_power']) * 1e-3 # lineic loss dB/m
self._f_loss_ref = squeeze(
kwargs['loss_coef']['frequency']) # Hz
else:
self._loss_coef = kwargs['loss_coef'] * 1e-3 # lineic loss dB/m
self._f_loss_ref = 193.5e12 # Hz
self._lin_attenuation = db2lin(self.length * self.loss_coef)
self._lin_loss_exp = self.loss_coef / (
10 * log10(exp(1))) # linear power exponent loss Neper/m
self._effective_length = (
1 - exp(-self.lin_loss_exp * self.length)) / self.lin_loss_exp
self._asymptotic_length = 1 / self.lin_loss_exp
# raman parameters (not compulsory)
self._raman_efficiency = kwargs[
'raman_efficiency'] if 'raman_efficiency' in kwargs else None
self._pumps_loss_coef = kwargs[
'pumps_loss_coef'] if 'pumps_loss_coef' in kwargs else None
except KeyError as e:
raise ParametersError(
f'Fiber configurations json must include {e}. Configuration: {kwargs}'
)