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Azimuth (Σ A ) is the angle in the satellite local horizontal plane between the projection of the velocity
vector onto this plane and the local north direction measured as positive in the clockwise direction. The
local horizontal defined in the BODY FIXED (rotating) coordinate system. Ranges from 0 to 360 degrees.
Velocity (V A ) is the magnitude of the BODY FIXED (rotating) velocity vector. This takes into account
rotation of the earth relative to the satellite.
4.1.6 Coordinate Frame Transformations
Orbital Elements EME2000
The perifocal r and v vectors are calculated from the orbital elements as follows. This transformation is
covered in detail in Reference12.
⃗⃗⃗⃗⃗
( )
[( ) ̂ ( ) ̂] (1)
⃗⃗⃗⃗ √ ( )
[( ) ̂ ( ) ̂] (2)
These vectors are transformed to a inertial (EME2000) coordinate system via the following 3-1-3
rotation. This transformation is covered in detail in Reference 12.
Where
⃗ [ ( ) ( ) ( )] ⃗⃗⃗⃗⃗ (3)
⃗ [ ( ) ( ) ( )] ⃗⃗⃗⃗ (4)
( ) [ ] (5)
( ) [ ] (6)
Inertial (EME2000) Orbital Elements
Use the following relationships to transfer an inertial (EME2000) r and v vector into orbital elements.
This transformation is covered in detail in Reference 12.
⃗ ⃗ (7)
̂ ⃗ (8)
‖ [( ) ⃗ ( ⃗ ⃗ ) ⃗ ]‖ (9)
( ) (10)
( ) (11)