Satellite

R2026b

Satellite in satellite scenario

Description

Satellite defines a satellite in satellite scenario object.

Creation

You can create Satellite objects using the satellite function of satelliteScenario object.

Properties

Name — Satellite name

string scalar | string vector | character vector | cell array of character vectors

You can set this property only when calling the satellite function. After you call satellite function, this property is read-only.

Satellite name, specified as a name-value argument consisting of 'Name' and a string scalar, string vector, character vector or a cell array of character vectors.

• If only one satellite is added, specify Name as a string scalar or a character vector.

• If multiple satellites are added, specify Name as a string scalar, character vector, string vector or a cell array of character vectors. All satellites added as a string scalar or a character vector are assigned the same specified name. The number of elements in the string vector or cell array of character vector must equal the number of satellites being added. Each satellite is assigned the corresponding name from the vector or cell array.

The default value when satellite is added to the satellite scenario using

• Keplerian orbital elements, TLE file — "Satellite ID", where ID is assigned by the satellite scenario.

• SEM almanac file or RINEX GPS navigation data — "PRN:prnValue", where prnValue is an integer denoting the pseudorandom noise code of the satellite as specified in the SEM almanac file.

• RINEX Galileo navigation data — "GAL Sat IF: id", where "id" is the satellite ID of the Galileo satellite defined in the RINEX navigation data.

• Timetable - Variable names of the timetable object.

• Timeseries - Name of the timeseries object if populated, otherwise "Satellite ID", where ID is assigned by satellite scenario.

Data Types: string

CentralBody — Central body

"Earth" (default) | "Moon"

Since R2026b

Celestial body relative to which the Keplerian element inputs (semimajorAxis, eccentricity, inclination, RAAN, argofperiapsis, and trueanomaly) or ephemeris data inputs (timetable or timeseries) are defined, specified as "Earth" or "Moon".

You can specify "Moon" only when using Keplerian element inputs or ephemeris data inputs. When CentralBody equals "Moon", TLE, OMM, SEM almanac, and RINEX data inputs are not supported and result in an error.

Note

Modification of this property requires an Aerospace Toolbox license. The following lunar operations check out this license: specifying CentralBody="Moon" in satellite, groundStation, or platform; specifying ReferenceCelestialBody="Moon"; specifying ObstructingBodies="Moon"; setting PlanetaryEphemerisModel on a satelliteScenario; and specifying CentralBody="Moon" in centralBodyOptions.

Dependencies

• When CentralBody equals "Moon" and you explicitly specify the OrbitPropagator name-value argument, it must equal "two-body-keplerian" or "numerical". When using timetable or timeseries inputs, the propagator is set to "ephemeris" automatically.

• When CoordinateFrame equals "ecef" or "geographic", the CentralBody is assumed to be "Earth" and this input is ignored.

Data Types: string

ID — Satellite ID assigned by simulator

real positive scalar

This property is set internally by the simulator and is read-only.

Satellite ID assigned by the simulator, specified as a positive scalar.

ConicalSensors — Conical sensors

row vector of conical sensors

You can set this property only when calling the conicalSensor. After you call the conicalSensor function, this property is read-only.

Conical sensors attached to the Satellite, specified as a row vector of conical sensors.

Gimbals — Gimbals

Read-only: row vector of Gimbal objects

This property is read-only.

You can set this property only when calling gimbal. After you call gimbal, this property is read-only.

Gimbals attached to the Satellite, specified as the name-value argument consisting of 'Gimbals' and a row vector of Gimbal objects.

Transmitters — Transmitters attached to Satellite

Read-only: row vector of Transmitter objects

This property is read-only.

You can set this property only when calling transmitter function. After you call the transmitter function, this property is read-only.

Transmitters attached to the Satellite, specified as a row vector of Transmitter objects.

Receivers — Receivers attached to the satellite

Read-only: row vector of Receiver objects

This property is read-only.

You can set this property only when calling the receiver. After you call the receiver function, this property is read-only.

Receivers attached to the satellite, specified as a row vector of Receiver objects.

Accesses — Access analysis objects

row vector of Access objects

You can set this property only when calling access. After you call access, this property is read-only.

Access analysis objects, specified as a row vector of Access objects.

GroundTrack — Ground track of the Satellite

row vector of GroundTrack objects

You can set this property only when calling groundTrack. After you call groundTrack, this property is read-only.

Ground track of the Satellite, specified as a row vector of GroundTrack objects.

CoordinateAxes — Coordinate axes triad graphic object

CoordinateAxes object (default)

You can set this property only when calling coordinateAxes. After you call coordinateAxes, this property is read-only.

Coordinate axes triad graphic object, specified as CoordinateAxes object.

Orbit — Orbit visualization

Orbit object

You can set this property only when calling orbit. After you call orbit, this property is read-only.

Orbit visualization parameters for a satellite, specified as an Orbit object.

Data Types: char | string

OrbitPropagator — Name of orbit propagator

"sgp4" | "sdp4" | "two-body-keplerian" | "ephemeris" | "gps" | "galileo" | "numerical"

You can set this property when you create a satellite object, and then this property becomes read-only.

Name of the orbit propagator used for propagating the satellite position and velocity, specified as one of these values:

• If you specify the satellite using timetable, table, timeseries, or tscollection, the OrbitPropagator value is "ephemeris".

• If you specify the satellite using a SEM almanac file or RINEX data containing a GPS navigation message, the OrbitPropagator value can be one of these values:

  • "gps" (default)

  • "sgp4"

  • "sdp4"

  • "two-body-keplerian"

  • "numerical"

• If you specify the satellite using the RINEX data containing a Galileo navigation message, the OrbitPropagator value can be one of these values:

  • "galileo" (default)

  • "sgp4"

  • "sdp4"

  • "two-body-keplerian"

  • "numerical"

• If you specify the satellite using Keplerian elements, OrbitPropagator value can be one of these values:

  • "two-body-keplerian"

  • "sgp4"

  • "sdp4"

  • "numerical"

  Additionally, if semimajor axis is negative, OrbitPropagator value can only be "numerical". If semimajor axis is positive, default value is "sgp4" for periods less than 225 min and "sdp4" for periods greater than or equal to 225 minutes.

• If you specify the satellite using a TLE or OMM file, the OrbitPropagator value can be one of these values:

  • "two-body-keplerian"

  • "sgp4"

  • "sdp4"

  • "numerical"

  If the orbital period is less than 225 minutes, the default OrbitPropagator value is "sgp4". Otherwise, the default OrbitPropagator value is "sdp4".

• If you specify the satellite using Keplerian elements, the OrbitPropagator value can be one of these values:

  • "two-body-keplerian"

  • "sgp4"

  • "sdp4"

If the RINEX data contains both valid GPS and Galileo navigation messages, you cannot specify OrbitPropagator as "gps" or "galileo" using a name-value argument. However, you can still specify it as "two-body-keplerian", "sgp4", "sdp4", or "numerical".

Dependencies

When CentralBody equals "Moon" and you explicitly specify the OrbitPropagator name-value argument, only "two-body-keplerian" and "numerical" are valid. Setting OrbitPropagator to "sgp4", "sdp4", "gps", or "galileo" when CentralBody equals "Moon" returns an error. When using timetable or timeseries inputs, the propagator is set to "ephemeris" automatically.

MarkerColor — Color of marker

[1 0.4118 0.1608] (default) | RGB triplet | string scalar of color name | character vector of color name

Color of the marker, specified as either an RGB triplet or a string or character vector of a color name.

For a custom color, specify an RGB triplet or a hexadecimal color code.

• An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1], for example, [0.4 0.6 0.7].

• A hexadecimal color code is a string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, the color codes "#FF8800", "#ff8800", "#F80", and "#f80" are equivalent.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

Color Name	Short Name	RGB Triplet	Hexadecimal Color Code	Appearance
"red"	"r"	[1 0 0]	"#FF0000"
"green"	"g"	[0 1 0]	"#00FF00"
"blue"	"b"	[0 0 1]	"#0000FF"
"cyan"	"c"	[0 1 1]	"#00FFFF"
"magenta"	"m"	[1 0 1]	"#FF00FF"
"yellow"	"y"	[1 1 0]	"#FFFF00"
"black"	"k"	[0 0 0]	"#000000"
"white"	"w"	[1 1 1]	"#FFFFFF"

Here are the RGB triplets and hexadecimal color codes for the default colors MATLAB^® uses in many types of plots.

RGB Triplet	Hexadecimal Color Code	Appearance
[0 0.4470 0.7410]	"#0072BD"
[0.8500 0.3250 0.0980]	"#D95319"
[0.9290 0.6940 0.1250]	"#EDB120"
[0.4940 0.1840 0.5560]	"#7E2F8E"
[0.4660 0.6740 0.1880]	"#77AC30"
[0.3010 0.7450 0.9330]	"#4DBEEE"
[0.6350 0.0780 0.1840]	"#A2142F"

Dependencies

On Aero.satellitescenario.CentralBodyOptions (Aerospace Toolbox) objects, this property is applicable only when the CentralBody property equals "Moon". Otherwise, this property is hidden and ignored.

MarkerSize — Size of marker

6 (default) | positive scalar less than 30

Size of the marker, specified as a real positive scalar less than 30. The unit is in pixels.

Dependencies

On Aero.satellitescenario.CentralBodyOptions (Aerospace Toolbox) objects, this property is applicable only when the CentralBody property equals "Moon". Otherwise, this property is hidden and ignored.

ShowLabel — State of Satellite label visibility

true or 1 (default) | false or 0

State of Satellite label visibility, specified as a name-value argument consisting of 'ShowLabel' and numerical or logical value of 1 (true) or 0 (false).

Dependencies

On Aero.satellitescenario.CentralBodyOptions (Aerospace Toolbox) objects, this property is applicable only when the CentralBody property equals "Moon". Otherwise, this property is hidden and ignored.

Data Types: logical

LabelFontColor — Font color of Satellite label

[1 0.4118 0.1608] (default) | RGB triplet | string scalar of color name | character vector of color name

Font color of the Satellite label, specified as a name-value argument consisting of 'LabelFontColor' and either an RGB triplet or a string or character vector of a color name.

For a custom color, specify an RGB triplet or a hexadecimal color code.

• An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1], for example, [0.4 0.6 0.7].

• A hexadecimal color code is a string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, the color codes "#FF8800", "#ff8800", "#F80", and "#f80" are equivalent.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

Color Name	Short Name	RGB Triplet	Hexadecimal Color Code	Appearance
"red"	"r"	[1 0 0]	"#FF0000"
"green"	"g"	[0 1 0]	"#00FF00"
"blue"	"b"	[0 0 1]	"#0000FF"
"cyan"	"c"	[0 1 1]	"#00FFFF"
"magenta"	"m"	[1 0 1]	"#FF00FF"
"yellow"	"y"	[1 1 0]	"#FFFF00"
"black"	"k"	[0 0 0]	"#000000"
"white"	"w"	[1 1 1]	"#FFFFFF"

Here are the RGB triplets and hexadecimal color codes for the default colors MATLAB uses in many types of plots.

RGB Triplet	Hexadecimal Color Code	Appearance
[0 0.4470 0.7410]	"#0072BD"
[0.8500 0.3250 0.0980]	"#D95319"
[0.9290 0.6940 0.1250]	"#EDB120"
[0.4940 0.1840 0.5560]	"#7E2F8E"
[0.4660 0.6740 0.1880]	"#77AC30"
[0.3010 0.7450 0.9330]	"#4DBEEE"
[0.6350 0.0780 0.1840]	"#A2142F"

Dependencies

On Aero.satellitescenario.CentralBodyOptions (Aerospace Toolbox) objects, this property is applicable only when the CentralBody property equals "Moon". Otherwise, this property is hidden and ignored.

LabelFontSize — Font size of Satellite label

15 (default) | positive scalar in the range [6 30]

Font size of the Satellite label, specified as a name-value argument consisting of 'LabelFontSize' and a positive scalar in the range [6 30].

Dependencies

On Aero.satellitescenario.CentralBodyOptions (Aerospace Toolbox) objects, this property is applicable only when the CentralBody property equals "Moon". Otherwise, this property is hidden and ignored.

Visual3DModel — Name of 3-D model file

zero-length string (default)

Name of the visual 3-D model file that you want to render in the viewer, specified as a string with .GLTF, .GLB, or .STL extension. For GLB and GLTF models, gITF uses a right-hand coordinate system. gITF defines +Y as up, and +Z as forward, and -X as right. A gITF asset faces +Z. For more information, see https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#coordinate-system-and-units. The mesh of the GLB is in meters.

Data Types: string

Visual3DModelScale — Linear scaling of 3-D model

1 (default) | nonnegative integer

Linear scaling of the visual 3-D model rendered in the viewer, specified as a nonnegative integer. The scaling assumes that the GLB model is in meters.

Data Types: double

Object Functions

access	Add access analysis objects to satellite scenario
aer	Calculate azimuth angle, elevation angle, and range of one asset with respect to another
dopplershift	Determine Doppler shift at target asset in satellite scenario
latency	Determine propagation delay from one asset to another asset
conicalSensor	Add conical sensor to satellite scenario
gimbal	Add gimbal to satellite, platform, or ground station
groundTrack	Add ground track object to satellite, platform or Moon in scenario
orbitalElements	Orbital elements of satellites in scenario
coordinateAxes	Visualize coordinate axes triad of satellite scenario assets
pointAt	Point satellite or gimbal at target
receiver	Add receiver to satellite scenario
transmitter	Add transmitter to satellite scenario
states	Obtain position and velocity of satellite or platform
show	Show object in satellite scenario viewer
hide	Hide satellite scenario entity from viewer
orbit	Visualize orbit in satellite scenario

Examples

Visualize Line of Sight Between Two Satellites

Create a satellite scenario object.

startTime = datetime(2020,5,5,0,0,0);
stopTime = startTime + days(1);
sampleTime = 60;                                      %seconds
sc = satelliteScenario(startTime,stopTime,sampleTime);

Add a satellite from a TLE file to the scenario.

tleFile = "eccentricOrbitSatellite.tle";
sat1 = satellite(sc,tleFile,"Name","Sat1")

sat1 = 
  Satellite with properties:

               Name:  Sat1
                 ID:  1
     ConicalSensors:  [1x0 matlabshared.satellitescenario.ConicalSensor]
            Gimbals:  [1x0 matlabshared.satellitescenario.Gimbal]
       Transmitters:  [1x0 satcom.satellitescenario.Transmitter]
          Receivers:  [1x0 satcom.satellitescenario.Receiver]
           Accesses:  [1x0 matlabshared.satellitescenario.Access]
        GroundTrack:  [1x1 matlabshared.satellitescenario.GroundTrack]
              Orbit:  [1x1 matlabshared.satellitescenario.Orbit]
    OrbitPropagator:  sdp4
        MarkerColor:  [0.059 1 1]
         MarkerSize:  6
          ShowLabel:  true
     LabelFontColor:  [1 1 1]
      LabelFontSize:  15

Add a satellite from Keplerian elements to the scenario and specify its orbit propagator to be "two-body-keplerian".

semiMajorAxis = 6878137;                                                                    %m
eccentricity = 0;
inclination = 20;                                                                           %degrees
rightAscensionOfAscendingNode = 0;                                                          %degrees
argumentOfPeriapsis = 0;                                                                    %degrees
trueAnomaly = 0;                                                                            %degrees
sat2 = satellite(sc,semiMajorAxis,eccentricity,inclination,rightAscensionOfAscendingNode,...
    argumentOfPeriapsis,trueAnomaly,"OrbitPropagator","two-body-keplerian","Name","Sat2")

sat2 = 
  Satellite with properties:

               Name:  Sat2
                 ID:  2
     ConicalSensors:  [1x0 matlabshared.satellitescenario.ConicalSensor]
            Gimbals:  [1x0 matlabshared.satellitescenario.Gimbal]
       Transmitters:  [1x0 satcom.satellitescenario.Transmitter]
          Receivers:  [1x0 satcom.satellitescenario.Receiver]
           Accesses:  [1x0 matlabshared.satellitescenario.Access]
        GroundTrack:  [1x1 matlabshared.satellitescenario.GroundTrack]
              Orbit:  [1x1 matlabshared.satellitescenario.Orbit]
    OrbitPropagator:  two-body-keplerian
        MarkerColor:  [0.059 1 1]
         MarkerSize:  6
          ShowLabel:  true
     LabelFontColor:  [1 1 1]
      LabelFontSize:  15

Add access analysis between the two satellites.

ac = access(sat1,sat2);

Determine the times when there is line of sight between the two satellites.

accessIntervals(ac)

ans = 15×8 table
    "Sat1"    "Sat2"    1    05-May-2020 00:09:00    05-May-2020 01:08:00    3540    1    1
    "Sat1"    "Sat2"    2    05-May-2020 01:50:00    05-May-2020 02:47:00    3420    1    1
    "Sat1"    "Sat2"    3    05-May-2020 03:45:00    05-May-2020 04:05:00    1200    1    1
    "Sat1"    "Sat2"    4    05-May-2020 04:32:00    05-May-2020 05:26:00    3240    1    1
    "Sat1"    "Sat2"    5    05-May-2020 06:13:00    05-May-2020 07:10:00    3420    1    1
    "Sat1"    "Sat2"    6    05-May-2020 07:52:00    05-May-2020 08:50:00    3480    1    1
    "Sat1"    "Sat2"    7    05-May-2020 09:30:00    05-May-2020 10:29:00    3540    1    1
    "Sat1"    "Sat2"    8    05-May-2020 11:09:00    05-May-2020 12:07:00    3480    1    2
    "Sat1"    "Sat2"    9    05-May-2020 12:48:00    05-May-2020 13:46:00    3480    2    2
    "Sat1"    "Sat2"    10    05-May-2020 14:31:00    05-May-2020 15:27:00    3360    2    2
    "Sat1"    "Sat2"    11    05-May-2020 17:12:00    05-May-2020 18:08:00    3360    2    2
    "Sat1"    "Sat2"    12    05-May-2020 18:52:00    05-May-2020 19:49:00    3420    2    2
    "Sat1"    "Sat2"    13    05-May-2020 20:30:00    05-May-2020 21:29:00    3540    2    2
    "Sat1"    "Sat2"    14    05-May-2020 22:08:00    05-May-2020 23:07:00    3540    2    2

Visualize the line of sight between the satellites.

play(sc);

Visualize GPS Constellation

Set up the satellite scenario.

startTime = datetime(2021,8,5);
stopTime = startTime + days(1);
sampleTime = 60;                                      % seconds
sc = satelliteScenario(startTime,stopTime,sampleTime);

Add satellites to the scenario from a SEM almanac file.

sat = satellite(sc,"gpsAlmanac.txt","OrbitPropagator","gps");

Visualize the GPS constellation.

v = satelliteScenarioViewer(sc);

References

[1] Hoots, Felix R., and Ronald L. Roehrich. Models for propagation of NORAD element sets. Aerospace Defense Command Peterson AFB CO Office of Astrodynamics, 1980.

[2] Vallado, David, et al. “Revisiting Spacetrack Report #3.” AIAA/AAS Astrodynamics Specialist Conference and Exhibit, American Institute of Aeronautics and Astronautics, 2006, https://doi.org/10.2514/6.2006-6753

Version History

Introduced in R2021a

R2024a: Satellite Scenario Unreal Assets

Starting R2024a, use the Visual3DModel (Aerospace Toolbox) property of Satellite to display a small satellite in satelliteScenarioViewer (Aerospace Toolbox) using the new SmallSat.glb model.

SmallSat

SmallSat.glb