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link

Add link analysis objects to transmitter

Description

example

link(asset1,asset2,...,assetN) adds Link analysis objects defined by nodes asset1, asset2, and so on.

lnk = link(___,NAME,VALUE) adds link analysis objects using additional parameters specified as name-value pairs.

lnk = link(___) adds link analysis objects and returns the vector link

Examples

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Create a satellite scenario object.

startTime = datetime(2020,11,25,0,0,0);
stopTime = startTime + days(1);
sampleTime = 60;                                     % seconds
sc = satelliteScenario(startTime,stopTime,sampleTime)
sc = 
  satelliteScenario with properties:

         StartTime: 25-Nov-2020
          StopTime: 26-Nov-2020
        SampleTime: 60
           Viewers: [0×0 matlabshared.satellitescenario.Viewer]
        Satellites: [1×0 matlabshared.satellitescenario.Satellite]
    GroundStations: [1×0 matlabshared.satellitescenario.GroundStation]
          AutoShow: 1

Add a satellite to the scenario.

semiMajorAxis = 10000000;                                                                  % meters
eccentricity = 0;
inclination = 60;                                                                          % degrees
rightAscensionOfAscendingNode = 0;                                                         % degrees
argumentOfPeriapsis = 0;                                                                   % degrees
trueAnomaly = 0;                                                                           % degrees
sat = satellite(sc,semiMajorAxis,eccentricity,inclination,rightAscensionOfAscendingNode,...
        argumentOfPeriapsis,trueAnomaly,"Name","Satellite");

Add a transmitter to the satellite.

frequency = 27e9;                                                                             % Hz
power = 20;                                                                                   % dBW
bitRate = 20;                                                                                 % Mbps
systemLoss = 3;                                                                               % dB
txSat = transmitter(sat,"Name","Satellite Transmitter","Frequency",frequency,"power",power,...
        "BitRate",bitRate,"SystemLoss",systemLoss)
txSat = 
  Transmitter with properties:

                Name:  Satellite Transmitter
                  ID:  2
    MountingLocation:  [0; 0; 0] meters
      MountingAngles:  [0; 0; 0] degrees
             Antenna:  [1x1 satcom.satellitescenario.GaussianAntenna]
          SystemLoss:  3 decibels
           Frequency:  2.7e+10 Hertz
             BitRate:  20 Mbps
               Power:  20 decibel-watts
               Links:  [1x0 satcom.satellitescenario.Link]

Add a receiver to the satellite.

gainToNoiseTemperatureRatio = 5;                                                                              % dB/K
systemLoss = 3;                                                                                               % dB
rxSat = receiver(sat,"Name","Satellite Receiver","GainToNoiseTemperatureRatio",gainToNoiseTemperatureRatio,...
        "SystemLoss",systemLoss)
rxSat = 
  Receiver with properties:

                           Name:  Satellite Receiver
                             ID:  3
               MountingLocation:  [0; 0; 0] meters
                 MountingAngles:  [0; 0; 0] degrees
                        Antenna:  [1x1 satcom.satellitescenario.GaussianAntenna]
                     SystemLoss:  3 decibels
    GainToNoiseTemperatureRatio:  5 decibels/Kelvin
                   RequiredEbNo:  10 decibels

Specify the antenna specifications of the repeater.

dishDiameter = 0.5;                                                                        % meters
apertureEfficiency = 0.5;
gaussianAntenna(txSat,"DishDiameter",dishDiameter,"ApertureEfficiency",apertureEfficiency);
gaussianAntenna(rxSat,"DishDiameter",dishDiameter,"ApertureEfficiency",apertureEfficiency);

Add two ground stations to the scenario.

gs1 = groundStation(sc,"Name","Ground Station 1");
latitude = 52.2294963;                                               % degrees
longitude = 0.1487094;                                               % degrees
gs2 = groundStation(sc,latitude,longitude,"Name","Ground Station 2");

Add gimbals to the ground stations. These gimbals enable you to steer the ground station antennas to track the satellite.

mountingLocation = [0; 0; -5];                                                              % meters
mountingAngles = [0; 180; 0];                                                               % degrees
gimbalGs1 = gimbal(gs1,"MountingLocation",mountingLocation,"MountingAngles",mountingAngles);
gimbalGs2 = gimbal(gs2,"MountingLocation",mountingLocation,"MountingAngles",mountingAngles);

Track the satellite using the gimbals.

pointAt(gimbalGs1,sat);
pointAt(gimbalGs2,sat);

Add a transmitter to gimbal gimbalGs1.

frequency = 30e9;                                                                             % Hz
power = 40;                                                                                   % dBW
bitRate = 20;                                                                                 % Mbps
txGs1 = transmitter(gimbalGs1,"Name","Ground Stationn 1 Transmitter","Frequency",frequency,...
        "Power",power,"BitRate",bitRate);

Add a receiver to gimbal gimbalGs2.

requiredEbNo = 14;                                                                          % dB
rxGs2 = receiver(gimbalGs2,"Name","Ground Station 2 Receiver","RequiredEbNo",requiredEbNo);

Define the antenna specifications of the ground stations.

dishDiameter = 5;                                   % meters
gaussianAntenna(txGs1,"DishDiameter",dishDiameter);
gaussianAntenna(rxGs2,"DishDiameter",dishDiameter);

Add link analysis to transmitter txGs1.

lnk = link(txGs1,rxSat,txSat,rxGs2)
lnk = 
  Link with properties:

    Sequence:  [8 3 2 9]
    LineWidth:  1
    LineColor:  [0 1 0]

Determine the times when ground station gs1 can send data to ground station gs2 via the satellite.

linkIntervals(lnk)
ans =

  0×8 empty table

Visualize the link using the Satellite Scenario Viewer.

play(sc);

Input Arguments

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Adds link analysis objects defined by nodes asset1, specified as a scalar or vector of transmitters, asset2, and so on, specified as a scalar or a vector of transmitters or receivers.

  • If the asset in a given node is scalar, every link analysis object uses the same asset for that node position.

  • If the asset in a given node is vector, the asset length must equal the number of link analysis objects.

Each link analysis object uses the corresponding element of the asset vector for that node location. The IDs of ASSET1, ASSET2, ASSET3, and so on, specify the Sequence of the link. These objects must belong to the same satelliteScenario object. Each link analysis object is added to the Link property of the corresponding transmitter in ASSET1.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: 'LineWidth',2.5 sets the line width of the field of view to 2.5 pixels.

Satellite scenario viewer, specified as a scalar, vector, or array of satelliteScenarioViewer objects. If the AutoSimulate property of the scenario is false, adding a satellite to the scenario disables any previously available timeline and playback widgets.

Output Arguments

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Link analysis object between input objects, returned as either a scalar or a row vector.

Note

When AutoSimulate of the satellite scenario is false, you can call link only when the SimulationStatus is NotStarted. Otherwise, you must call the restart function to erase the simulation data and reset the SimulationStatus to NotStarted.

Version History

Introduced in R2021a