def model():
return pylink.DAGModel([pylink.Geometry(),
pylink.Antenna(is_rx=True),
pylink.Interconnect(is_rx=True),
pylink.Receiver(),
pylink.Transmitter(),
pylink.Interconnect(is_rx=False),
pylink.Antenna(is_rx=False),
pylink.Channel(),
pylink.Modulation(name='QPSK', perf=perf),
pylink.LinkBudget()])
is_rx=False,
tracking=False)
gs_rx_antenna = pylink.Antenna(pattern=pylink.pattern_generator(48),
rx_noise_temp_k=300,
polarization='RHCP',
is_rx=True,
tracking=True)
gs_tx_antenna = pylink.Antenna(gain=25,
polarization='RHCP',
is_rx=False,
tracking=True)
sat_receiver = pylink.Receiver(rf_chain=sat_rf_chain,
implementation_loss_db=2,
name='Satellite SBand Receiver')
gs_receiver = pylink.Receiver(rf_chain=gs_rf_chain,
name='Ground SBand Receiver')
gs_transmitter = pylink.Transmitter(tx_power_at_pa_dbw=23,
name='Ground SBand Transmitter')
sat_transmitter = pylink.Transmitter(tx_power_at_pa_dbw=1.5,
name='Satellite XBand Transmitter')
rx_interconnect = pylink.Interconnect(is_rx=True)
tx_interconnect = pylink.Interconnect(is_rx=False)
def satellite_init(self):
# build the receive RF chain
self.sat_rf_chain = [
pylink.Element(name='Cables',
gain_db=self.sampler(self.satellite_configuration,
['rx', 'cable', 'gain']),
noise_figure_db=self.sampler(
self.satellite_configuration,
['rx', 'cable', 'noise_figure'])),
pylink.Element(name='LNA',
gain_db=self.sampler(self.satellite_configuration,
['rx', 'lna', 'gain']),
noise_figure_db=self.sampler(
self.satellite_configuration,
['rx', 'lna', 'noise_figure'])),
pylink.Element(name='Filter',
gain_db=self.sampler(self.satellite_configuration,
['rx', 'filter', 'gain']),
noise_figure_db=self.sampler(
self.satellite_configuration,
['rx', 'filter', 'noise_figure'])),
pylink.Element(name='Demodulator',
gain_db=self.sampler(self.satellite_configuration,
['rx', 'demodulator', 'gain']),
noise_figure_db=self.sampler(
self.satellite_configuration,
['rx', 'demodulator', 'noise_figure'])),
]
# if no gain given, calculate from the antenna aperture
if 'gain' in self.satellite_configuration['nominal']['rx']['antenna']:
sat_rx_antenna_gain = self.sampler(self.satellite_configuration,
['rx', 'antenna', 'gain'])
if 'aperture' in self.satellite_configuration['nominal']['rx'][
'antenna'] and self.warn:
print(
"Satellite Rx Antenna: Both gain and aperature provided, will use gain"
)
else:
sat_rx_antenna_gain = 10 * np.log10(
self.sampler(self.satellite_configuration,
['rx', 'antenna', 'aperture_efficiency']) *
self.sampler(self.satellite_configuration,
['rx', 'antenna', 'aperture']) * 4 * np.pi *
(1e6 * self.sampler(self.channel_configuration,
['uplink', 'center_freq']))**2 /
scipy.constants.c**2)
# specify the receive antenna
self.sat_rx_antenna = pylink.Antenna(
gain=sat_rx_antenna_gain,
polarization=self.satellite_configuration['nominal']['rx']
['antenna']['polarization'],
pattern=self.sampler(self.satellite_configuration,
['rx', 'antenna', 'pattern']),
is_rx=True,
tracking=self.satellite_configuration['nominal']['rx']['antenna']
['tracking'],
pointing_loss_db=self.sampler(self.satellite_configuration,
['rx', 'antenna', 'pointing_loss']),
rx_noise_temp_k=self.sampler(self.satellite_configuration,
['rx', 'antenna', 'noise_temp']))
# if no gain given, calculate from the antenna aperture
if 'gain' in self.satellite_configuration['nominal']['tx']['antenna']:
sat_tx_antenna_gain = self.sampler(self.satellite_configuration,
['tx', 'antenna', 'gain'])
if 'aperture' in self.satellite_configuration['nominal']['tx'][
'antenna'] and self.warn:
print(
"Satellite Tx Antenna: Both gain and aperature provided, will use gain"
)
else:
sat_tx_antenna_gain = 10 * np.log10(
self.sampler(self.satellite_configuration,
['tx', 'antenna', 'aperture_efficiency']) *
self.sampler(self.satellite_configuration,
['tx', 'antenna', 'aperture']) * 4 * np.pi *
(1e6 * self.sampler(self.channel_configuration,
['downlink', 'center_freq']))**2 /
scipy.constants.c**2)
self.sat_tx_antenna = pylink.Antenna(
gain=sat_tx_antenna_gain,
polarization=self.satellite_configuration['nominal']['tx']
['antenna']['polarization'],
pattern=self.sampler(self.satellite_configuration,
['tx', 'antenna', 'pattern']),
is_rx=False,
tracking=self.satellite_configuration['nominal']['tx']['antenna']
['tracking'],
pointing_loss_db=self.sampler(self.satellite_configuration,
['rx', 'antenna', 'pointing_loss']))
self.sat_receiver = pylink.Receiver(
rf_chain=self.sat_rf_chain,
implementation_loss_db=self.sampler(
self.satellite_configuration,
['rx', 'receiver', 'implementation_loss']),
name='Satellite ' +
self.channel_configuration['nominal']['uplink']['name'] +
' Receiver')
self.sat_transmitter = pylink.Transmitter(
tx_power_at_pa_dbw=self.sampler(self.satellite_configuration,
['tx', 'pa', 'power']),
name='Satellite ' +
self.channel_configuration['nominal']['downlink']['name'] +
' Transmitter')
#!/usr/bin/python
import pylink
"""Illustrations of the precedence order for node definitions.
Nodes are added to the DAG in the order in which they are received.
So you can, if you wish, override a standard definition.
"""
# Vanilla link budget
m = pylink.DAGModel([
pylink.Geometry(),
pylink.Transmitter(tx_power_at_pa_dbw=2),
pylink.Interconnect(is_rx=False),
pylink.Antenna(is_rx=False),
pylink.Receiver(),
pylink.Antenna(is_rx=True),
pylink.Interconnect(is_rx=True),
pylink.Channel(),
pylink.Modulation('DVB-S2X'),
pylink.LinkBudget()
])
e = m.enum
print 'Link margin in vanilla example: %s' % m.link_margin_db
# let's override the link_margin_db node in the kwargs
def _evil_margin_db(model):
return -3.0
