ARTS built-in documentation server

Workspace Method ppathFromRtePos2


Determines the propagation path from rte_pos2 to rte_pos.

The propagation path linking rte_pos and rte_pos2 is calculated
and returned. The method determines the path in a pure numerical
manner, where a simple algorithm is applied. The task is to find
the value of rte_los (at rte_pos) linking the two positions.

See the user guide for a description of the search algorithm,
including a more detailed definition of *za_accuracy*, 
*pplrt_factor* and *pplrt_lowest*.

The standard application of this method should be to radio link
calculations, where rte_pos2 corresponds to a transmitter, and
rte_pos to the receiver/sensor.

The details of the ray tracing is controlled by ppath_step_agenda
as usual.

Authors: Patrick Eriksson


ppathFromRtePos2( ppath, rte_los, ppath_lraytrace, ppath_step_agenda, atmosphere_dim, p_grid, lat_grid, lon_grid, z_field, f_grid, refellipsoid, z_surface, rte_pos, rte_pos2, ppath_lmax, za_accuracy, pplrt_factor, pplrt_lowest )


OUTppath(Ppath)The propagation path for one line-of-sight.
OUT+INrte_los(Vector)A line-of-sight for (complete) radiative transfer calculations.
OUT+INppath_lraytrace(Numeric)Maximum length of ray tracing steps when determining propagation paths.
INppath_step_agenda(Agenda)Agenda calculating a propagation path step.
INatmosphere_dim(Index)The atmospheric dimensionality (1-3).
INp_grid(Vector)The pressure grid.
INlat_grid(Vector)The latitude grid.
INlon_grid(Vector)The longitude grid.
INz_field(Tensor3)The field of geometrical altitudes.
INf_grid(Vector)The frequency grid for monochromatic pencil beam calculations.
INrefellipsoid(Vector)Reference ellipsoid.
INz_surface(Matrix)The surface altitude.
INrte_pos(Vector)A geographical position for starting radiative transfer calculations.
INrte_pos2(Vector)A second geographical position to define the geometry for radiative transfer calculations.
INppath_lmax(Numeric)Maximum length between points describing propagation paths.
GINza_accuracy(Numeric, Default: 2e-5)Required accuracy, in form of the maximum allowed angular off-set [deg].
GINpplrt_factor(Numeric, Default: 5)The factor with which ppath_lraytrace is decreased if no solution is found.
GINpplrt_lowest(Numeric, Default: 0.5)Lowest value ppath_lraytrace to consider. The calculations are halted if this length is passed.