CL_gm_stationPointing

Description

• Computes the spherical coordinates (elevation, West azimuth, distance) of any object as seen from one or several locations (stations). The locations are defined by their elliptical ("geodetic") coordinates.

  The positions (pos) are given in cartesian coordinates in the same frame as stations.

  The outputs can be described by the res argument:

  - "azim" : azimuth (positive towards West)

  - "elev" : elevation

  - "dist" : distance

  - "s" : structure containing the fields "azim", "elev", "dist"

  - "l" : list of spherical coordinates for each station

• See Local frames for more details on the definition of local frames.

Parameters

stations:

Stations positions in elliptical (geodetic) coordinates [long,lat,alt] [rad,m] (3xP)

pos:

Positions of object in the same frame as "stations", in cartesian coordinates [m] (3xN)

res:

(string) vector of names: "azim", "elev", "dist", "s" or "l". Default is ["azim", "elev", "dist"] (1xQ)

er :

(optional) Planet's equatorial radius. Default is %CL_eqRad [m] (1x1)

obla :

(optional) Planet's oblateness. Default is %CL_obla (1x1)

res1, res2...:

results: Elevation [rad] (PxN), azimuth [rad] (PxN), distance [m] (PxN), structure (PxN fields) or list

Authors

• CNES - DCT/SB

See also

• CL_gm_stationVisiLocus

Examples

// satellite positions pos = [[7.e6; 0; 0], [7.e6; 1.e3; 0], [7.e6; 2.e3; 0]]; // ground stations (geodetic coordinates) stations = [[0;0;0], [0.1; 0.2; 0]] // Coordinates in topocentric North frame (size of results: 2x3) [azim,elev,dist] = CL_gm_stationPointing(stations, pos); // List of 3x1 coordinates l = CL_gm_stationPointing(stations, pos, res="l");