Status of link closure between first and last node
Obtain Closed Downlink Status History
Create a satellite scenario object.
startTime = datetime(2020,10,13,5,30,0); stopTime = datetime(2020,10,13,5,45,0); sampleTime = 60; % seconds sc = satelliteScenario(startTime,stopTime,sampleTime);
Add a satellite to the scenario.
semiMajorAxis = 10000000; % meters eccentricity = 0; inclination = 0; % degrees rightAscensionOfAscendingNode = 0; % degrees argumentOfPeriapsis = 0; % degrees trueAnomaly = 210; % degrees sat = satellite(sc,semiMajorAxis,eccentricity, ... inclination,rightAscensionOfAscendingNode, ... argumentOfPeriapsis,trueAnomaly);
Add a transmitter to the satellite.
tx = transmitter(sat);
Add a ground station to the scenario.
latitude = 0; % degrees longitude = 30; % degrees gs = groundStation(sc,latitude,longitude);
Add a receiver to the ground station.
rx = receiver(gs,"MountingAngles",[0; 180; 0]);
Create a downlink.
lnk = link(tx,rx);
Obtain the link status history of the closed downlink.
s = linkStatus(lnk)
s = 1x16 logical array 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
lnk — Link analysis
Link object vector |
Link object scalar
Link analysis object, specified as a
vector or scalar.
timeIn — Time at which output is calculated
Time at which the output is calculated, specified as a
datetime scalar. If
no time zone is specified in
timeIn, the time zone is assumed to be
Universal Time Coordinated (UTC).
s — Link closure status
matrix of logical values
Link closure status, returned as a matrix of logical values representing the link
closure status history
s of each link in the vector
link. The rows of the matrix correspond to the link objects in
link and the columns correspond to the time sample. The status at
a given instant is
true) if the link between
first and last node is closed. The link between the first and last node is closed when
the link between each individual pair of intermediate adjacent nodes in the Sequence
property of the link is closed.
For a given pair, the link is considered to be closed when both nodes belong to the same satellite or ground station.
Otherwise, the link between the pair is closed if the directionality is from a transmitter to a receiver and the energy per bit to noise power spectral density ratio (Eb/No) at the receiver is greater than its
Additionally, if a given node is attached to a ground station directly or via a gimbal, the elevation angle of the adjacent node with respect to the ground station must be greater than or equal to its MinElevationAngle.
timeOut — Time samples of output link status
scalar | vector
Time samples of output link status, returned as a scalar or a vector. If time
history of link status is returned,
timeOut is a row vector.