edges.analysis.loss

Functions defining expected losses from the instruments.

edges.analysis.loss.antenna_loss(freq: ndarray, filename: str | Path, instrument: str | None = None, configuration: str = '')[source]

Calculate antenna loss of a particular antenna at given frequencies.

Parameters:

  • filename (path) – File in which value of the antenna loss for this instrument are tabulated.

  • freq (array-like) – Frequency in MHz. For mid-band (low-band), between 50 and 150 (120) MHz.

  • instrument – The instrument to find the antenna loss for. Only required if filename starts with the magic ‘:’ (in which case the standard directory structure will be searched using band).

  • configuration (str, optional) – The configuration of the instrument. A string, such as “45deg”, which defines the orientation or other configuration parameters of the instrument, which may affect the antenna loss.

edges.analysis.loss.ground_loss(freq: ndarray, filename: str | Path, instrument: str | None = None, configuration: str = '') → ndarray[source]

Calculate ground loss of a particular antenna at given frequencies.

Parameters:

  • filename (path) – File in which value of the ground loss for this instrument are tabulated.

  • freq (array-like) – Frequency in MHz. For mid-band (low-band), between 50 and 150 (120) MHz.

  • instrument (str, optional) – The instrument to find the ground loss for. Only required if filename doesn’t exist and isn’t an absolute path (in which case the standard directory structure will be searched using band).

  • configuration (str, optional) – The configuration of the instrument. A string, such as “45deg”, which defines the orientation or other configuration parameters of the instrument, which may affect the ground loss.

edges.analysis.loss.low2_balun_connector_loss(ants11: ~edges.cal.sparams.core.datatypes.ReflectionCoefficient | str | ~pathlib.Path, use_approx_eps0: bool = True, connector: ~edges.cal.sparams.core.network_component_models.CoaxialCable = CoaxialCable(conductivities={'copper': <Quantity 59600000. S / m>, 'brass': <Quantity 17284000. S / m>, 'stainless steel': <Quantity 1430400. S / m>, 'tinned copper': <Quantity 47680000. S / m>, 'silver plated copper': <Quantity 59600000. S / m>}, outer_radius=<Quantity 0.0805 inch>, inner_radius=<Quantity 0.025 inch>, outer_material='stainless steel', inner_material='copper', relative_dielectric=2.05, outer_conductivity=<Quantity 1430400. S / m>, inner_conductivity=<Quantity 14304000. S / m>, relative_conductance_interior=0.0002, length=<Quantity 0.03 m>, _eps0=<<class 'astropy.constants.codata2018.EMCODATA2018'> name='Vacuum electric permittivity' value=8.8541878128e-12 uncertainty=1.3e-21 unit='F / m' reference='CODATA 2018'>), balun: ~edges.cal.sparams.core.network_component_models.CoaxialCable = CoaxialCable(conductivities={'copper': <Quantity 59600000. S / m>, 'brass': <Quantity 17284000. S / m>, 'stainless steel': <Quantity 1430400. S / m>, 'tinned copper': <Quantity 47680000. S / m>, 'silver plated copper': <Quantity 59600000. S / m>}, outer_radius=<Quantity 0.375 inch>, inner_radius=<Quantity 0.15625 inch>, outer_material='brass', inner_material='copper', relative_dielectric=1.07, outer_conductivity=<Quantity 17284000. S / m>, inner_conductivity=<Quantity 59600000. S / m>, relative_conductance_interior=0.0, length=<Quantity 43.6 inch>, _eps0=<<class 'astropy.constants.codata2018.EMCODATA2018'> name='Vacuum electric permittivity' value=8.8541878128e-12 uncertainty=1.3e-21 unit='F / m' reference='CODATA 2018'>)) → ndarray[tuple[Any, ...], dtype[_ScalarT]][source]

Obtain the balun and connector loss for the low-2 instrument on-site at MRO.

Parameters:

  • freq – An array of frequencies at which to calculate the balun+connector loss.

  • ants11 – The antenna S11, either as a numpy array, a path to a file containing the S11, or a S11Model instance.

  • use_approx_eps0 (bool, optional) – Whether to approximate the vacuum electric permittivity as 8.854e-12 F/m instead of the ~10-digit accuracy it has from astropy. This is mainly for backward compatibility with previous results. Default is True.

  • connector – The connector to use. Default is the SC3792 connector.

  • balun – The balun to use. Default is the lowband-balun-tube.

Returns:

loss (np.ndarray) – The balun+connector loss as a function of frequency (same length as freq).