accessStatus

Status of access between first and last node defining access analysis

Since R2021a

Syntax

s = accessStatus(ac)

s = accessStatus(ac,timeIn)

[s,timeOut] = accessStatus(___)

Description

s = accessStatus(ac) returns a matrix s of the access status history between the first and last node corresponding to each access object in the input vector ac.

s = accessStatus(ac,timeIn) returns the status of each access analysis object at the specified datetime in timeIn. Each element of s corresponds to an access object in ac.

[s,timeOut] = accessStatus(___) returns the status of each access analysis object and the corresponding datetime in Coordinated Universal Time (UTC).

Examples

Obtain Access Status Between Satellite and Ground Station

Create a satellite scenario object.

startTime = datetime(2021,4,30);                      % 30 April 2021, 12:00 AM UTC
stopTime = datetime(2021,5,1);                        % 1 May 2021, 12:00 AM UTC
sampleTime = 60;                                      % seconds
sc = satelliteScenario(startTime,stopTime,sampleTime);

Add a satellite to the scenario.

semiMajorAxis = 10000000;                             % meters
eccentricity = 0;
inclination = 10;                                     % degrees
rightAscensionOfAscendingNode = 0;                    % degrees
argumentOfPeriapsis = 0;                              % degrees
trueAnomaly = 0;                                      % degrees
sat = satellite(sc,semiMajorAxis,eccentricity, ...
    inclination,rightAscensionOfAscendingNode, ...
    argumentOfPeriapsis,trueAnomaly);

Add a ground station to the scenario.

gs = groundStation(sc);

Add access analysis between the satellite and the ground station.

ac = access(sat,gs);

Obtain the access status at 30 April 2021, 5:34 PM UTC.

time = datetime(2021,4,30,17,34,0);
s = accessStatus(ac,time)

s = logical
   0

Input Arguments

ac — Access analysis

row vector of Access objects

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

timeIn — Time at which output is calculated

datetime scalar

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 UTC.

Outputs Arguments

s — Access analysis status

column vector | matrix

Access analysis status, returned as a column vector or a matrix. If timeIn is specified, s is a column vector. Otherwise, the output is a matrix. The rows of the matrix correspond to the access object in ac, and the columns correspond to the time sample. The status at a given instant is 1 (true) if access exists between each pair of adjacent nodes defined by Sequence. For example, in a given pair, defined by node 1 and node 2, node 1 has access to node 2 and node 2 has access to node 1:

• If a node is a satellite, then the satellite has access to the adjacent node when both nodes are in line of sight of each other.

• If a node is a ground station, then the ground station has access to the adjacent node when the elevation angle of the node with respect to the ground station is greater than or equal to the MinElevationAngle property of GroundStation.

• If a node is a conical sensor, then the conical sensor has access to the adjacent node when the latter is in the field of view of the former. If the conical sensor is attached to a ground station directly or via a gimbal, then the elevation angle of the adjacent node with respect to the ground station must be greater than or equal to the MinElevationAngle property of GroundStation.

timeOut — Time samples of output access status

scalar | vector

Time samples of the output access status, returned as a scalar or vector. If the time history of the access status is returned, timeOut is a row vector.

Note

When the AutoSimulate property of the satellite scenario is true, the access status history from StartTime to StopTime is returned. When the property is false, the access status history from StartTime to SimulationTime is returned.

Version History

Introduced in R2021a