start_time = time.time()
sIP = mSF.coord_satellite(rinex_nav, rinex_obs, sats_write_1)
print "Coord satellites has been computed in"
print("--- %s seconds ---" % (time.time() - start_time))
except ValueError:
print 'station ' + str(rinex_obs.nam) + ' has been skipped'
continue
################################################################################
lista_G = []
sIP_G_list = []
data_list = []
start_time = time.time()
for sa in sats_write_1:
varion = mO.obs_sat(rinex_obs.data[0], rinex_obs.data[1],
rinex_obs.data[2], rinex_obs.data[3],
rinex_obs.data[4], sa)
data_list.append(rinex_obs.data)
lista_G.append(varion)
sIP_sat = mSF.track_sat(sIP, sa, start, stop)
####
phi_ipp, lambda_ipp, h_ipp = mSF.coord_ipps(
rinex_obs.xyz[0], rinex_obs.xyz[1], rinex_obs.xyz[2],
sIP_sat[2], sIP_sat[3], sIP_sat[4], h_iono)
sIP_G_list.append((sIP_sat[0], sIP_sat[1], phi_ipp, lambda_ipp,
sIP_sat[6], sIP_sat[7]))
print "VARION algorithm has been computed and"
print "IPP location has been computed for the satellites selected in"
print("--- %s seconds ---" % (time.time() - start_time))
################################################################################
def coord_satellite(rinex_nav, rinex_obs, sats_write):
'''
inputs:
- rinex navigation file (also brdc)
- rinex obs file
outputs:
- array of the prn
- array of the sod
- array of the X of the satellites
- array of the Y of the satellites
- array of the Z of the satellites
- array of the time of Time of Ephemeris (seconds into GPS week)
'''
##### CONSTANTS
# WGS 84 value of earth's univ. grav. par.
mu = 3.986005e14
# WGS 84 value of earth's rotation rate
omegae = 7.2921151467e-5
pigreco = 3.1415926535898
speedOfLight = 299792458.0
# relativistic correction term constant (not used so far)
F = -4.442807633E-10
# WGS-84 earth rotation rate
we = 7.292115e-5
## READING THE NAVIGATION RINEX
data = RN.readRinexNav(rinex_nav)
prn = (np.asarray(data['sv'])) # PRN number
te = (np.asarray(data['TimeEph'])
) # Time of Ephemeris (seconds into GPS week)
a = (np.asarray(data['sqrtA']))**2 # Semi-major axis (meters)
mo = (np.asarray(data['M0'])) # Mean anomaly at reference time (radians)
e = (np.asarray(data['Eccentricity'])) # Eccentricity (unitless)
cuc = (
np.asarray(data['Cuc'])
) # Amplitude of the cosine harmonic correction term to the argument of latitude (radians)
cus = (
np.asarray(data['Cus'])
) # Amplitude of the sine harmonic correction term to the argument of latitude (radians)
crc = (
np.asarray(data['Crc'])
) # Amplitude of the cosine harmonic correction term to the orbit radius (meters)
crs = (
np.asarray(data['Crs'])
) # Amplitude of the sine harmonic correction term to the orbit radius (meters)
cic = (
np.asarray(data['Cic'])
) # Amplitude of the cosine harmonic correction term to the angle of inclination (radians)
cis = (
np.asarray(data['CIS'])
) # Amplitude of the sine harmonic correction term to the angle of inclination (radians)
dn = (np.asarray(data['DeltaN'])
) # Mean motion difference from computed value (radians/sec)
lo = (np.asarray(data['OMEGA'])
) # longitude of ascending node of orbit plane at weekly epoch
ome = (np.asarray(data['omega'])) # argument of perigee (radians)
ome_dot = (np.asarray(data['OMEGA DOT'])
) # Rate of right ascension (radians/sec)
i_init = (np.asarray(data['Io'])
) # Inclination angle at reference time (radians)
i_rate = (np.asarray(data['IDOT'])
) # Rate of inclination angle (radians/sec)
gps_week_sat = np.asarray(data['GPSWeek'])
no = (mu / (a**3))**0.5
n = no + dn
## READING THE OBSERVATION RINEX -- > in order to compute the Xs,Ys,Zs at the epochs we want
data_obs = rinex_obs.data
prn_sat_list = []
Xk_list = []
Yk_list = []
Zk_list = []
Az_list = []
El_list = []
sod_list = []
toe_list = []
for s in sats_write:
prn_sat = int(s[1:3])
varion, ora, sod = mO.obs_sat(data_obs[0], data_obs[1], data_obs[2],
data_obs[3], data_obs[4], s)
for i in xrange(len(sod)):
# Time of flight
tof = data_obs[-1][1:][i] / speedOfLight
### correction due to the earth rotation
# alpha = tof * we
trasmitTime = (sod[i] + rinex_obs.gps_sow_ref) - tof
tk_arr = (trasmitTime - te[prn == prn_sat]) # tk = t - te
val, idx = min(
(val, idx)
for (idx,
val) in enumerate(np.abs(tk_arr))) # vedo quale tk è min
tk = tk_arr[idx] + (rinex_obs.gps_week_ref -
gps_week_sat[prn == prn_sat][idx]) * 604800
## TEST
if tk > 302400:
tk = tk - 604800
if tk < -302400:
tk = tk + 604800
mk = mo[prn == prn_sat][idx] + n[prn == prn_sat][idx] * tk
## iterazioni per calcolare Ek
eko = mk
for j in xrange(50):
ek = mk + e[prn == prn_sat][idx] * np.sin(eko)
if abs(ek - eko) <= 10e-10: break
else:
eko = ek
if j == 49:
print "WARNING: Kepler Eqn didn't converge for sat " + str(
s)
break
##
vk = np.arctan2(
(((1 - (e[prn == prn_sat][idx])**2)**0.5) * np.sin(ek)),
(np.cos(ek) - e[prn == prn_sat][idx]))
uk = ome[prn == prn_sat][idx] + vk
duk = (cuc[prn == prn_sat][idx] * np.cos(2 * uk) +
(cus[prn == prn_sat][idx] * np.sin(2 * uk)))
drk = (crc[prn == prn_sat][idx] * np.cos(2 * uk) +
(crs[prn == prn_sat][idx] * np.sin(2 * uk)))
dik = (cic[prn == prn_sat][idx] * np.cos(2 * uk) +
(cis[prn == prn_sat][idx] * np.sin(2 * uk)))
omek = ome[prn == prn_sat][idx] + duk
rk = a[prn == prn_sat][idx] * (
1 - e[prn == prn_sat][idx] * np.cos(ek)) + drk
ik = i_init[prn ==
prn_sat][idx] + i_rate[prn == prn_sat][idx] * tk + dik
xk = rk * np.cos(omek + vk)
yk = rk * np.sin(omek + vk)
lk = lo[prn == prn_sat][idx] + ome_dot[prn == prn_sat][
idx] * tk - omegae * (sod[i] + rinex_obs.gps_sow_ref)
Xk = xk * np.cos(lk) - yk * np.sin(lk) * np.cos(ik)
Yk = xk * np.sin(lk) + yk * np.cos(lk) * np.cos(ik)
Zk = yk * np.sin(ik)
# Correction the satellite position for the time it took the message to get to the reciver
#Xk = Xk * np.cos(alpha) + Yk * np.sin(alpha)
#Yk = -Xk * np.sin(alpha) + Yk * np.cos(alpha)
Az, El = calculateAzimuthElevation(Xk, Yk, Zk, rinex_obs)
Xk_list.append(Xk)
Yk_list.append(Yk)
Zk_list.append(Zk)
Az_list.append(Az)
El_list.append(El)
prn_sat_list.append(s)
sod_list.append(sod[i])
toe_list.append(te[prn == prn_sat][idx])
prn_sat_arr = np.asarray(prn_sat_list)
sod_arr = np.asarray(sod_list)
toe_arr = np.asarray(toe_list)
Xk_arr = np.asarray(Xk_list)
Yk_arr = np.asarray(Yk_list)
Zk_arr = np.asarray(Zk_list)
Az_arr = np.asarray(Az_list)
El_arr = np.asarray(El_list)
return prn_sat_arr, sod_arr, Xk_arr, Yk_arr, Zk_arr, toe_arr, Az_arr, El_arr
def coord_satellite(rinex_nav, rinex_obs, sats_write):
'''
inputs:
- rinex navigation file (also brdc)
- rinex obs file
outputs:
- array of the prn
- array of the sod
- array of the X of the satellites
- array of the Y of the satellites
- array of the Z of the satellites
- array of the time of Time of Ephemeris (seconds into GPS week)
'''
##### CONSTANTS
# WGS 84 value of earth's univ. grav. par.
mu = 3.986005e14
# WGS 84 value of earth's rotation rate
omegae = 7.2921151467e-5
pigreco = 3.1415926535898
speedOfLight = 299792458.0
# relativistic correction term constant (not used so far)
F = -4.442807633E-10
# WGS-84 earth rotation rate
we = 7.292115e-5
## READING THE NAVIGATION RINEX
epoch, sow, prn, te, a, mo, e, cuc, cus, crc, crs, cic, cis, dn, lo, ome, ome_dot, i_init, i_rate, gps_week_sat = RN.nav_gps_v2_new(
rinex_nav)
no = (mu / (a**3))**0.5
n = no + dn
## READING THE OBSERVATION RINEX -- > in order to compute the Xs,Ys,Zs at the epochs we want
rinex_obs.data = skip_nan(rinex_obs, rinex_obs.data[5])
data_obs = rinex_obs.data
sat_gps = rinex_obs.data[0]
ora_gps = rinex_obs.data[1]
sod_gps = rinex_obs.data[2]
c1c_gps = rinex_obs.data[5]
l1c_gps = rinex_obs.data[3]
c2w_gps = rinex_obs.data[6]
l2w_gps = rinex_obs.data[4]
c5_gps = rinex_obs.data[9]
l5_gps = rinex_obs.data[10]
prn_sat_list = []
Xk_list = []
Yk_list = []
Zk_list = []
Az_list = []
El_list = []
sod_list = []
toe_list = []
for s in sats_write:
prn_sat = int(s[1:3])
print s
varion, ora, sod = mO.obs_sat(sat_gps, ora_gps, sod_gps, l1c_gps,
l2w_gps, s)
for i in xrange(len(sod)):
# Time of flight
tof = c1c_gps[1:][i] / speedOfLight
### correction due to the earth rotation
# alpha = tof * we
trasmitTime = (sod[i] + rinex_obs.gps_sow_ref) - tof
tk_arr = (trasmitTime - te[prn == prn_sat]) # tk = t - te
val, idx = min(
(val, idx)
for (idx,
val) in enumerate(np.abs(tk_arr))) # vedo quale tk è min
tk = tk_arr[idx] + (rinex_obs.gps_week_ref -
gps_week_sat[prn == prn_sat][idx]) * 604800
## TEST
if tk > 302400:
tk = tk - 604800
if tk < -302400:
tk = tk + 604800
mk = mo[prn == prn_sat][idx] + n[prn == prn_sat][idx] * tk
## iterazioni per calcolare Ek
eko = mk
for j in xrange(50):
ek = mk + e[prn == prn_sat][idx] * np.sin(eko)
if np.isnan(abs(ek - eko)) == True:
pdb.set_trace()
if abs(ek - eko) <= 10e-10: break
else:
eko = ek
if j == 49:
print "WARNING: Kepler Eqn didn't converge for sat " + str(
s)
break
##
vk = np.arctan2(
(((1 - (e[prn == prn_sat][idx])**2)**0.5) * np.sin(ek)),
(np.cos(ek) - e[prn == prn_sat][idx]))
uk = ome[prn == prn_sat][idx] + vk
duk = (cuc[prn == prn_sat][idx] * np.cos(2 * uk) +
(cus[prn == prn_sat][idx] * np.sin(2 * uk)))
drk = (crc[prn == prn_sat][idx] * np.cos(2 * uk) +
(crs[prn == prn_sat][idx] * np.sin(2 * uk)))
dik = (cic[prn == prn_sat][idx] * np.cos(2 * uk) +
(cis[prn == prn_sat][idx] * np.sin(2 * uk)))
omek = ome[prn == prn_sat][idx] + duk
rk = a[prn == prn_sat][idx] * (
1 - e[prn == prn_sat][idx] * np.cos(ek)) + drk
ik = i_init[prn ==
prn_sat][idx] + i_rate[prn == prn_sat][idx] * tk + dik
xk = rk * np.cos(omek + vk)
yk = rk * np.sin(omek + vk)
lk = lo[prn == prn_sat][idx] + ome_dot[prn == prn_sat][
idx] * tk - omegae * (sod[i] + rinex_obs.gps_sow_ref)
Xk = xk * np.cos(lk) - yk * np.sin(lk) * np.cos(ik)
Yk = xk * np.sin(lk) + yk * np.cos(lk) * np.cos(ik)
Zk = yk * np.sin(ik)
# Correction the satellite position for the time it took the message to get to the reciver
#Xk = Xk * np.cos(alpha) + Yk * np.sin(alpha)
#Yk = -Xk * np.sin(alpha) + Yk * np.cos(alpha)
Az, El = calculateAzimuthElevation(Xk, Yk, Zk, rinex_obs)
Xk_list.append(Xk)
Yk_list.append(Yk)
Zk_list.append(Zk)
Az_list.append(Az)
El_list.append(El)
prn_sat_list.append(s)
sod_list.append(sod[i])
toe_list.append(te[prn == prn_sat][idx])
prn_sat_arr = np.asarray(prn_sat_list)
sod_arr = np.asarray(sod_list)
toe_arr = np.asarray(toe_list)
Xk_arr = np.asarray(Xk_list)
Yk_arr = np.asarray(Yk_list)
Zk_arr = np.asarray(Zk_list)
Az_arr = np.asarray(Az_list)
El_arr = np.asarray(El_list)
return prn_sat_arr, sod_arr, Xk_arr, Yk_arr, Zk_arr, toe_arr, Az_arr, El_arr