SimpleGeom

MATLAB

G = SimpleGeom(hp,ht,rd,[vp],[vt],...
         [PlatformHeading],[TargetHeading],[EarthRadius])

Description

Returns geometry structure with platform and target position, velocity in ECF coordinates given a simplified list of input geometry specifications. Target will be placed at Lat = 0, Long = 0 at specified altitude, and platform will be located on the prime meridian (Long = 0) in the southern hemisphere at a latitude consistent with the input platform-to-target ground range, rd. Assumes level flight of platform and target at (optional) specified headings. If speed of platform or target not specified, vp, vt default to zero. If heading is not specified for platform, target, or wind, heading = 90 degrees (due east) is default.

Parameters

Parameters	Description
hp [scalar]	Altitude of platform above curved earth surface (m)
ht [scalar]	Altitude of target above curved earth surface (m)
rd [scalar]	Ground range of target from platform along earth surface (m)
vp [scalar]	(Optional) Speed of platform (default is zero) (m/s)
vt [scalar]	(Optional) Speed of target (default is zero) (m/s)
PlatformHeading [scalar]	(Optional) Heading clockwise from due north (default is 90) (deg).
TargetHeading [scalar]	(Optional) Heading clockwise from due north (default is 90 unless vt is 0, then the default is PlatformHeading) (deg)
EarthRadius [scalar]	(Optional) Spherical Earth Radius (defaults to value from PhysicalConst) (m)

Return Values

Return Values	Description
G [struct]	Geometry structure to be input to EngagementStruct or to update engagement case definition.
G.Coordinates [string]	Coordinate frame for geometry specification 'ECF'
G.RP [vector]	Platform position vector in ECF Coords (m)
G.VP [vector]	Platform velocity vector in ECF Coords (m/s)
G.RT [vector]	Target position vector in ECF Coords (m)
G.VT [vector]	Target velocity vector in ECF Coords (m/s)
G.TALO [empty]	Placeholder for target Time-After-Lift-Off
G.EarthRadius [scalar]	Earth radius used (m).