this procedure initializes the sgp4 propagator. all the initialization is
consolidated here instead of having multiple loops inside other routines.
author : david vallado 719-573-2600 28 jun 2005
inputs :
ecco - eccentricity 0.0 - 1.0
epoch - epoch time in days from jan 0, 1950. 0 hr
inclo - inclination of satellite
no - mean motion of satellite
satn - satellite number
outputs :
ainv - 1.0 / a
ao - semi major axis
con41 -
con42 - 1.0 - 5.0 cos(i)
cosio - cosine of inclination
cosio2 - cosio squared
eccsq - eccentricity squared
method - flag for deep space 'd', 'n'
omeosq - 1.0 - ecco * ecco
posq - semi-parameter squared
rp - radius of perigee
rteosq - square root of (1.0 - ecco*ecco)
sinio - sine of inclination
gsto - gst at time of observation rad
no - mean motion of satellite
locals :
ak -
d1 -
del -
adel -
po -
coupling :
getgravconst
gstime - find greenwich sidereal time from the julian date
procedure initl
this procedure initializes the sgp4 propagator. all the initialization is consolidated here instead of having multiple loops inside other routines.
author : david vallado 719-573-2600 28 jun 2005
inputs : ecco - eccentricity 0.0 - 1.0 epoch - epoch time in days from jan 0, 1950. 0 hr inclo - inclination of satellite no - mean motion of satellite satn - satellite number
outputs : ainv - 1.0 / a ao - semi major axis con41 - con42 - 1.0 - 5.0 cos(i) cosio - cosine of inclination cosio2 - cosio squared eccsq - eccentricity squared method - flag for deep space 'd', 'n' omeosq - 1.0 - ecco * ecco posq - semi-parameter squared rp - radius of perigee rteosq - square root of (1.0 - ecco*ecco) sinio - sine of inclination gsto - gst at time of observation rad no - mean motion of satellite
locals : ak - d1 - del - adel - po -
coupling : getgravconst gstime - find greenwich sidereal time from the julian date
references : hoots, roehrich, norad spacetrack report #3 1980 hoots, norad spacetrack report #6 1986 hoots, schumacher and glover 2004 vallado, crawford, hujsak, kelso 2006