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Workspace Method sensor_responseMetMM

Description

Sensor setup for meteorological millimeter instruments.

This method is handy if you are simulating a passband-type instrument,
consisting of a few discrete channels.

For flexibility, the Met-MM system is seperated in two calculation
steps. To fully use the system, create f_grid (and some associated
variables) by f_gridMetMM before calling this method. However, it is
possible to use this method with any f_grid, as long as matching
f_backend, channel2fgrid_indexes and channel2fgrid_weights
are provided.

Each scan sequence is treated as a measurement block. sensor_pos is
set in the standard way. The number of rows in sensor_pos determines the
number of scan sequences that will be simulated. On the other hand,
sensor_los is handled in a special way. All zenith angles must be set
to 180 deg. For 3D, the given azimuth angles are taken as the direction
of scanning, where the azimuth angle is defined with respect to North
in standard manner. For example, if the scanning happens to move from
SW to NE, the azimuth angle should be set to 45 deg. The angles of the
scanning sequence are taken from antenna_dlos. This WSV is here only
allowed to have a single column, holding relative zenith angles. For
3D, the azimuth angles in antenna_dlos are hard-coded to zero. As
zenith angles in sensor_los are locked to 180 deg, antenna_dlos
effectively holds the nadir angles. These angles can be both positive or
negative, where the recommended choice is to operate with negative
to end up with final zenith angles between 0 and 180 deg.

The method does not support 2D atmospheres (across-track scanning is
inconsistent with 2D). For simpler switching between 1D and 3D,
the argument *mirror_dza* is at hand. It can only be used for 3D.
If set to true, the zenith angles in antenna_dlos are mapped
to also cover the other side of the swath and the simulations will
cover both sides of the swath.

Authors: Oliver Lemke, Patrick Eriksson

Synopsis

sensor_responseMetMM( antenna_dim, mblock_dlos_grid, sensor_response, sensor_response_f, sensor_response_pol, sensor_response_dlos, sensor_response_f_grid, sensor_response_pol_grid, sensor_response_dlos_grid, sensor_norm, atmosphere_dim, stokes_dim, f_grid, f_backend, channel2fgrid_indexes, channel2fgrid_weights, iy_unit, antenna_dlos, met_mm_polarisation, met_mm_antenna, use_antenna, mirror_dza )

Variables

OUTantenna_dim(Index)The dimensionality of the antenna pattern (1-2).
OUTmblock_dlos_grid(Matrix)The set of angular pencil beam directions for each measurement block.
OUTsensor_response(Sparse)The matrix modelling the total sensor response.
OUTsensor_response_f(Vector)The frequencies associated with the output of sensor_response.
OUTsensor_response_pol(ArrayOfIndex)The polarisation states associated with the output of sensor_response.
OUTsensor_response_dlos(Matrix)The relative zenith and azimuth angles associated with the output of sensor_response.
OUTsensor_response_f_grid(Vector)The frequency grid associated with sensor_response.
OUTsensor_response_pol_grid(ArrayOfIndex)The "polarisation grid" associated with sensor_response.
OUTsensor_response_dlos_grid(Matrix)The zenith and azimuth angles associated with sensor_response.
OUTsensor_norm(Index)Flag if sensor response should be normalised or not (0 or 1).
INatmosphere_dim(Index)The atmospheric dimensionality (1-3).
INstokes_dim(Index)The dimensionality of the Stokes vector (1-4).
INf_grid(Vector)The frequency grid for monochromatic pencil beam calculations.
INf_backend(Vector)The frequency position of each backend (spectrometer) channel.
INchannel2fgrid_indexes(ArrayOfArrayOfIndex)Definition of backend frequency response, link to f_grid.
INchannel2fgrid_weights(ArrayOfVector)Definition of backend frequency response, weighting of f_grid.
INiy_unit(String)Selection of output unit for radiative transfer methods.
INantenna_dlos(Matrix)The relative line-of-sight of each antenna pattern.
INmet_mm_polarisation(ArrayOfString)The polarisation for meteorological millimeter instruments.
INmet_mm_antenna(Vector)The antenna beam width for meteorological millimeter instruments.
GINuse_antenna(Index, Default: 0)Flag to enable (1) or disable (0) antenna.
GINmirror_dza(Index, Default: 0)Flag to include second part of swath (only 3D, see above).