GS_Ariel.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Wed Apr 10 16:42:50 2019

@author: Sébastien Durand
"""

from astropy import units as u
from astropy.coordinates import GCRS, CartesianRepresentation, EarthLocation, AltAz
from astropy.time import Time
from tqdm import tqdm
import numpy as np

import time_function as tt
import ccsds as cc

#_________________________________START Fonction____________________________

def ground_station_intervisibility(time_vector,sat_gcrs, ground_station):
    
    for gs in range(len(ground_station)):

        sat_altaz = sat_gcrs[0].transform_to(AltAz(obstime=time_vector[0],location=ground_station[gs][1]))
        sat_altaz_GS = [[sat_altaz.az.value],[sat_altaz.alt.value]]
        
        for i in tqdm(range(1,len(time_vector)), ascii=True, desc="Convert frame to ALT_AZ frame :"):
            sat_altaz = sat_gcrs[i].transform_to(AltAz(obstime=time_vector[i],location=ground_station[gs][1]))
            sat_altaz_GS[0].append(sat_altaz.az.value)
            sat_altaz_GS[1].append(sat_altaz.alt.value)
                  
    return sat_altaz_GS


#_________________________________END Fonction____________________________


#_________________________START Personal specification_______________________

t_start = Time(60096, format='mjd')
t_end = Time(60316, format='mjd')
time_interval = 60*u.s
orbit_sat_file='TRAJ_0012.txt'

ground_station = [["French Guiana",EarthLocation(lat=5.251*u.deg, lon=-52.804*u.deg, height=15*u.m),0,'00001']]


#_________________________END Personal specification_______________________

# create time_vector
time_vector = tt.time_step_gen(time_interval.to('s').value, 
                               t_start, t_end, 
                               input_type="astropy", output_type="astropy")
time_vector = Time(time_vector,format='mjd', scale='utc')

# read sat orbit
cic, origin, comment, header, data_time, data_science = cc.read_ccsds(orbit_sat_file)

# convert sat orbit in astropy position
sat_gcrs= GCRS(obstime=time_vector, x=data_science.T[0]*u.km, y=data_science.T[1]*u.km, z=data_science.T[2]*u.km, representation_type=CartesianRepresentation)

#reduce sat data
sat_gcrs=sat_gcrs[:10000]
time_vector=time_vector[:10000]

#_________________________________START SCRIPT____________________________

# produce Ground station intervisibility
time_event, event_type, visibility_GS, sat_altaz_GS = ground_station_intervisibility(time_vector,sat_gcrs, ground_station)