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Workspace Method sensor_responseAntenna


Includes response of the antenna.

The function returns the sensor response matrix after the antenna
characteristics have been included.

The function handles "multi-beam" cases where the polarisation
coordinate system is the same for all beams.

See antenna_dim, antenna_dlos and antenna_response for
details on how to specify the antenna response.

The text below refers to mblock_dlos despite it is not an input
to the method. The method instead uses sensor_response_dlos_grid
but the values in this WSV are likely coming from mblock_dlos.

One dimensional antenna patterns are handled as other response
functions. That is, both antenna response and radiances are treated
as piece-wise linear functions, and the pencil beam calculations
must cover the full sensor response (i.e. mblock_dlos shall be
sufficiently broad).

There exist different options for two dimensional antenna patterns.
(If 2D, the GIN *option_2d* must be set, the default setting results
in an error). A normalisation is always applied for 2D antennas.

Both radiances and the antenna pattern are treated as step-wise
constant functions. The antenna pattern is interpolated to the
mblock_dlos directions. At extrapolation, the antenna response
is set to zero. This option considers GIN *solid_angles*, that
shall be a vector with length matching the rows of mblock_dlos.
The values going into sensor_response are the interpolated antenna
values times the corresponding solid angle.

This option is more similar to the 1D case. The radiances are treated
as a bi-linear function, but the antenna response is treated as step-
wise constant function (in contrast to 1D). For this option
mblock_dlos must match a combination of zenith and azimuth
grids, and this for a particular order. If the zenith and azimuth
grids have 3 and 2 values, respectively, the order shall be:
  [(za1,aa1); (za2,aa1); (za3,aa1); (za1,aa2); (za2,aa2); (za3,aa2)]
Both these grids must be strictly increasing and as for 1D must cover
the antenna response completely.

Authors: Patrick Eriksson, Mattias Ekstrom


sensor_responseAntenna( sensor_response, sensor_response_f, sensor_response_pol, sensor_response_dlos, sensor_response_dlos_grid, sensor_response_f_grid, sensor_response_pol_grid, atmosphere_dim, antenna_dim, antenna_dlos, antenna_response, sensor_norm, option_2d, solid_angles )


OUT+INsensor_response(Sparse)The matrix modelling the total sensor response.
OUT+INsensor_response_f(Vector)The frequencies associated with the output of sensor_response.
OUT+INsensor_response_pol(ArrayOfIndex)The polarisation states associated with the output of sensor_response.
OUT+INsensor_response_dlos(Matrix)The relative zenith and azimuth angles associated with the output of sensor_response.
OUT+INsensor_response_dlos_grid(Matrix)The zenith and azimuth angles associated with sensor_response.
INsensor_response_f_grid(Vector)The frequency grid associated with sensor_response.
INsensor_response_pol_grid(ArrayOfIndex)The "polarisation grid" associated with sensor_response.
INatmosphere_dim(Index)The atmospheric dimensionality (1-3).
INantenna_dim(Index)The dimensionality of the antenna pattern (1-2).
INantenna_dlos(Matrix)The relative line-of-sight of each antenna pattern.
INantenna_response(GriddedField4)The antenna pattern/response.
INsensor_norm(Index)Flag if sensor response should be normalised or not (0 or 1).
GINoption_2d(String, Default: "-")Calculation option for 2D antenna cases. See above for details.
GINsolid_angles(Vector, Default: [])The solid angle of each mblock_dlos direction. Only considered for 2D with "interp_response".