Visualize Multiplatform Scenario

This example shows how to create and display a multiplatform scenario containing a ground-based stationary radar, a turning airplane, a constant-velocity airplane, and a moving ground vehicle. The turning airplane follows a parabolic flight path while descending at a rate of 20 m/s.

Specify the scenario refresh rate at 0.5 Hz. For 150 steps, the time duration of the scenario is 300 s.

updateRate = 0.5;
N = 150;

Set up the turning airplane using the Acceleration model of the phased.Platform System object?. Specify the initial position of the airplane by range and azimuth from the ground-based radar and its elevation. The airplane is 10 km from the radar at 60? azimuth and has an altitude of 6 km. The airplane is accelerating at 10 in the negative x-direction.

airplane1range = 10.0e3;
airplane1Azimuth = 60.0;
airplane1alt = 6.0e3;
airplane1Pos0 = [cosd(airplane1Azimuth)*airplane1range;...
    sind(airplane1Azimuth)*airplane1range;airplane1alt];
airplane1Vel0 = [400.0;-100.0;-20];
airplane1Accel = [-10.0;0.0;0.0];
airplane1platform = phased.Platform('MotionModel','Acceleration',...
    'AccelerationSource','Input port','InitialPosition',airplane1Pos0,...
    'InitialVelocity',airplane1Vel0,'OrientationAxesOutputPort',true,...
    'InitialOrientationAxes',eye(3));

Set up the stationary ground radar at the origin of the global coordinate system. To simulate a rotating radar, change the ground radar beam steering angle in the processing loop.

groundRadarPos = [0,0,0]';
groundRadarVel = [0,0,0]';
groundradarplatform = phased.Platform('MotionModel','Velocity',...
    'InitialPosition',groundRadarPos,'Velocity',groundRadarVel,...
    'InitialOrientationAxes',eye(3));

Set up the ground vehicle to move at a constant velocity.

groundVehiclePos = [5e3,2e3,0]';
groundVehicleVel = [50,50,0]';
groundvehicleplatform = phased.Platform('MotionModel','Velocity',...
    'InitialPosition',groundVehiclePos,'Velocity',groundVehicleVel,...
    'InitialOrientationAxes',eye(3));

Set up the second airplane to also move at constant velocity.

airplane2Pos = [8.5e3,1e3,6000]';
airplane2Vel = [-300,100,20]';
airplane2platform = phased.Platform('MotionModel','Velocity',...
    'InitialPosition',airplane2Pos,'Velocity',airplane2Vel,...
    'InitialOrientationAxes',eye(3));

Set up the scenario viewer. Specify the radar as having a beam range of 8 km, a vertical beam width of 30?, and a horizontal beam width of 2?. Annotate the tracks with position, speed, altitude, and range.

BeamSteering = [0;50];
viewer = phased.ScenarioViewer('BeamRange',8.0e3,'BeamWidth',[2;30],'UpdateRate',updateRate,...
    'PlatformNames',{'Ground Radar','Turning Airplane','Vehicle','Airplane 2'},'ShowPosition',true,...
    'ShowSpeed',true,'ShowAltitude',true,'ShowLegend',true,'ShowRange',true,...
    'Title','Multiplatform Scenario','BeamSteering',BeamSteering);

Step through the display processing loop, updating radar and target positions. Rotate the ground-based radar steering angle by four degrees at each step.

for n = 1:N
    [groundRadarPos,groundRadarVel] = groundradarplatform(updateRate);
    [airplane1Pos,airplane1Vel,airplane1Axes] = airplane1platform(updateRate,airplane1Accel);
    [vehiclePos,vehicleVel] = groundvehicleplatform(updateRate);
    [airplane2Pos,airplane2Vel] = airplane2platform(updateRate);
    viewer(groundRadarPos,groundRadarVel,[airplane1Pos,vehiclePos,airplane2Pos],...
        [airplane1Vel,vehicleVel,airplane2Vel]);
    BeamSteering = viewer.BeamSteering(1);
    BeamSteering = mod(BeamSteering + 4,360.0);
    if BeamSteering > 180.0
        BeamSteering = BeamSteering - 360.0;
    end
    viewer.BeamSteering(1) = BeamSteering;
    pause(0.2);
end