MCRadar

A radar 3D foward Monte Carlo radiative algorithm, that allows for 2D antenna patterns and arbitrary sensor positions. Surface reflections are currently ignored.

The main output variable y and mc_error represent the radar reflectivity integrated over the antenna function, and the estimated error in this vector, respectively.

Unlike with yRadar, the range bins gives the boundaries of the range bins as either round-trip time or distance from radar.

The WSV mc_y_tx gives the polarization state of the transmitter.

The WSV mc_max_scatorder prescribes the maximum scattering order to consider, after which ‘photon’-tracing will be terminated. A value of one calculates only single scattering.

The WSV mc_max_iter describes the maximum number of ‘photons’ used in the simulation (more photons means smaller mc_error ). The method will terminate once the max_iter criterium is met. If negative values are given for these parameters then it is ignored.

Here “1” and “Ze” are the allowed options for iy_unit_radar. The value of mc_error follows the selection for iy_unit_radar (both for in- and output. See yRadar() for details of the units.

Author(s): Ian S. Adams

Parameters:

y (Vector, optional) – The measurement vector. See y, defaults to self.y [OUT]
mc_error (Vector, optional) – Error in simulated y when using a Monte Carlo approach. See mc_error, defaults to self.mc_error [OUT]
mc_antenna (MCAntenna, optional) – Antenna pattern description for dedicated MC calculaions. See mc_antenna, defaults to self.mc_antenna [IN]
f_grid (Vector, optional) – The frequency grid for monochromatic pencil beam calculations. See f_grid, defaults to self.f_grid [IN]
f_index (Index, optional) – Frequency index. See f_index, defaults to self.f_index [IN]
sensor_pos (Matrix, optional) – The sensor position for each measurement block. See sensor_pos, defaults to self.sensor_pos [IN]
sensor_los (Matrix, optional) – The sensor line-of-sight (LOS) for each measurement block. See sensor_los, defaults to self.sensor_los [IN]
stokes_dim (Index, optional) – The dimensionality of the Stokes vector (1-4). See stokes_dim, defaults to self.stokes_dim [IN]
atmosphere_dim (Index, optional) – The atmospheric dimensionality (1-3). See atmosphere_dim, defaults to self.atmosphere_dim [IN]
ppath_lmax (Numeric, optional) – Maximum length between points describing propagation paths. See ppath_lmax, defaults to self.ppath_lmax [IN]
ppath_step_agenda (Agenda, optional) – Calculation of a propagation path step. See ppath_step_agenda, defaults to self.ppath_step_agenda [IN]
ppath_lraytrace (Numeric, optional) – Maximum length of ray tracing steps when determining propagation. See ppath_lraytrace, defaults to self.ppath_lraytrace [IN]
propmat_clearsky_agenda (Agenda, optional) – Calculate the absorption coefficient matrix. See propmat_clearsky_agenda, defaults to self.propmat_clearsky_agenda [IN]
p_grid (Vector, optional) – The pressure grid. See p_grid, defaults to self.p_grid [IN]
lat_grid (Vector, optional) – The latitude grid. See lat_grid, defaults to self.lat_grid [IN]
lon_grid (Vector, optional) – The longitude grid. See lon_grid, defaults to self.lon_grid [IN]
z_field (Tensor3, optional) – The field of geometrical altitudes. See z_field, defaults to self.z_field [IN]
refellipsoid (Vector, optional) – Reference ellipsoid. See refellipsoid, defaults to self.refellipsoid [IN]
z_surface (Matrix, optional) – The surface altitude. See z_surface, defaults to self.z_surface [IN]
t_field (Tensor3, optional) – The field of atmospheric temperatures. See t_field, defaults to self.t_field [IN]
vmr_field (Tensor4, optional) – VMR field. See vmr_field, defaults to self.vmr_field [IN]
cloudbox_on (Index, optional) – Flag to activate the cloud box. See cloudbox_on, defaults to self.cloudbox_on [IN]
cloudbox_limits (ArrayOfIndex, optional) – The limits of the cloud box. See cloudbox_limits, defaults to self.cloudbox_limits [IN]
pnd_field (Tensor4, optional) – Particle number density field. See pnd_field, defaults to self.pnd_field [IN]
scat_data (ArrayOfArrayOfSingleScatteringData, optional) – Array of single scattering data. See scat_data, defaults to self.scat_data [IN]
mc_y_tx (Vector, optional) – Normalized Stokes vector for transmittance (e.g., radar). See mc_y_tx, defaults to self.mc_y_tx [IN]
range_bins (Vector, optional) – The range bins of an active instrument. See range_bins, defaults to self.range_bins [IN]
atmfields_checked (Index, optional) – OK-flag for atmospheric grids and (physical) fields. See atmfields_checked, defaults to self.atmfields_checked [IN]
atmgeom_checked (Index, optional) – OK-flag for the geometry of the model atmosphere. See atmgeom_checked, defaults to self.atmgeom_checked [IN]
scat_data_checked (Index, optional) – OK-flag for scat_data. See scat_data_checked, defaults to self.scat_data_checked [IN]
cloudbox_checked (Index, optional) – OK-flag for variables associated with the cloudbox. See cloudbox_checked, defaults to self.cloudbox_checked [IN]
iy_unit_radar (String, optional) – Unit for radar simulations. See iy_unit_radar, defaults to self.iy_unit_radar [IN]
mc_max_scatorder (Index, optional) – The maximum scattering order allowed for Monte Carlo. See mc_max_scatorder, defaults to self.mc_max_scatorder [IN]
mc_seed (Index, optional) – The integer seed for the random number generator used by. See mc_seed, defaults to self.mc_seed [IN]
mc_max_iter (Index, optional) – The maximum number of iterations allowed for Monte Carlo. See mc_max_iter, defaults to self.mc_max_iter [IN]
ze_tref (Numeric, optional) – Reference temperature for conversion to Ze. Defaults to 273.15 [IN]
k2 (Numeric, optional) – Reference dielectric factor. Defaults to -1 [IN]
t_interp_order (Index, optional) – Interpolation order of temperature for scattering data (so far only applied in phase matrix, not in extinction and absorption. Defaults to 1 [IN]
verbosity (Verbosity) – ARTS verbosity. See verbosity, defaults to self.verbosity [IN]