def gpsTime2y_doy_hms(week, gpsTime):
""" Function to convert GPS time to year, doy and hour minutes seconds
"""
iepy = 1980
iepd = 6
# Hour of the day
ss = math.fmod(gpsTime, rtcm_ssr2osr.Constants().day_seconds)
hh = np.floor(ss / 3600)
# Conversion to time of year
# Number of days since iepy
ndy = week * 7 + np.floor(
(gpsTime - ss) / rtcm_ssr2osr.Constants().day_seconds + 0.5) + iepd - 1
# Number of years since iepy
ny = np.floor(ndy / 365.25)
# Current year
iy = np.floor(iepy + ny)
# Day of the year
DOY = np.floor(ndy - ny * 365.25 + 1)
# Minutes
ss = math.fmod(ss, 3600)
mm = np.floor(ss / 60)
# Seconds
ss = math.fmod(ss, 60)
return iy, DOY, hh, mm, ss
def ell2cart(lat, long, height):
""" Coordinates transformation using WGS84 ellipsoid definition
Input:
- lat : ellipsoidal latitude
- lon : ellipsoidal longitude
- height: ellipsoidal height
Output:
- [x,y,z] vector of geocentric-cartesian coordinates
Reference:
- "Satellite Geodesy", Seeber
"""
h = height
lat = np.radians(lat)
long = np.radians(long)
a = rtcm_ssr2osr.Constants().WGS84_a
f = rtcm_ssr2osr.Constants().WGS84_f
N_bar = a / np.sqrt(1 - f * (2 - f) * (np.sin(lat))**2)
# Cartesian coordinates:
x = (N_bar + h) * np.cos(lat) * np.cos(long)
y = (N_bar + h) * np.cos(lat) * np.sin(long)
z = (((1 - f)**2) * N_bar + h) * np.sin(lat)
cart = np.array([x, y, z])
return cart
def glo_time2gps_time(glo_day, glo_time, glo_year, ls):
# Moscow day -> UTC day
if glo_time >= 10800.0:
utc_time = glo_time - 10800.0
else:
utc_time = glo_time - 10800.0 + rtcm_ssr2osr.Constants().day_seconds
# compute gregorian date
[day, mon, year] = glo_time2greg_day(glo_day, glo_year)
# compute day of the year
doy = date_to_doy(year, mon, day)
# get gps week and time
[gps_week, gps_time] = gps_time_from_y_doy_hms(year, doy, 0, 0,
utc_time + ls)
return gps_week, gps_time
def gps_time_from_y_doy_hms(year, doy, hh, mm, sec):
"""
Compute gps time from date as year, doy, hours, minutes, seconds
"""
iepy = 1980
iepd = 6
if year < 100:
if year > 80:
year += 1900
else:
year += 2000
ndy = ((year - iepy) * 365 + doy - iepd + ((year - 1901) / 4) -
((iepy - 1901) / 4))
week = (ndy / 7)
time = (round(
(week - int(week)) * 7) * rtcm_ssr2osr.Constants().day_seconds +
hh * 3600.0e0 + mm * 60.0e0 + sec)
return int(week), time
def __init__(self, epoch, state, rec, system, ID, f1, iono):
self.epoch = epoch
self.sat = state[0:3]
self.rec = rec
self.re = rtcm_ssr2osr.Constants().re
self.omega_e = rtcm_ssr2osr.Constants().omega_e # [rad/s]
self.system = system
self.layers = iono.n_layers
for l in range(self.layers):
self.height = iono.height[l]
self.sh_deg = iono.degree[l]
self.sh_ord = iono.order[l]
self.c = iono.c[l][:]
self.s = iono.s[l][:]
[lat_sph, lon_sph, height_sph,
el, az, psi_pp,
lambda_pp, phi_pp,
sf, sun_shift, lon_s,
p_nm, p_cos, p_sin, m, n,
vtec] = IonoComputation.compute_global_iono(self)
stec = vtec * sf
self.stec_corr_f1 = 40.3 * 1e16 / (f1 * f1) * stec
strg = ('### SV pos/vel for SV ' + ID + ' at ' + f'{epoch}' +
': ' + '{:16.4f}'.format(state[0]) + ' ' +
'{:16.4f}'.format(state[1]) + ' ' +
'{:16.4f}'.format(state[2]) + ' [m]' + ' ' +
'{:9.4f}'.format(state[3]) + ' ' +
'{:9.4f}'.format(state[4]) + ' ' +
'{:9.4f}'.format(state[5]) + ' [m/s]' + '\n' +
'PPt at t=' +
f'{epoch}' + '(sun shift= ' +
'{:11.8f}'.format(sun_shift * 180 / np.pi) +
' deg)' + ' \n' +
'PPt from Ref phi_R= ' +
'{:11.8f}'.format(lat_sph * 180 / np.pi) + ' lam_R=' +
'{:11.8f}'.format(lon_sph * 180 / np.pi) +
' rE+hR= ' + '{:10.3f}'.format(height_sph + 6370000) +
'(spherical!)' + '\n' +
'PPt from Ref to SV at elev= ' +
'{:11.8f}'.format(el * 180 / np.pi) + ' azim ' +
'{:11.8f}'.format(az * 180 / np.pi) +
'(spherical!)' + '\n' +
'PPt psi_pp= ' +
'{:11.8f}'.format(psi_pp * 180 / np.pi) +
' phi_pp ' +
'{:11.8f}'.format(phi_pp * 180 / np.pi) +
' lam_pp ' +
'{:11.8f}'.format(lambda_pp * 180 / np.pi) +
' lon_S ' +
'{:11.8f}'.format(lon_s * 180 / np.pi) +
' rE+hI: ' +
'{:10.3f}'.format(self.height * 1000 + 6370000) + '\n'
'Pnm : ')
# Lagrange Polynomials
for o in range(len(p_nm)):
m_ind = int(m[o])
n_ind = int(n[o])
strg = (strg + 'P(' + f'{n_ind}' + ',' +
f'{m_ind}' + ')=' +
'{:7.4f}'.format(p_nm[o]) + '; ')
# Cosines
strg = strg + '\n' + 'Pcos: '
for o in range(len(p_cos)):
m_ind = int(m[o])
n_ind = int(n[o])
strg = (strg + 'P(' + f'{n_ind}' + ',' +
f'{m_ind}' + ')=' +
'{:7.4f}'.format(p_cos[o]) + '; ')
# Sines
strg = strg + '\n' + 'Psin: '
for o in range(len(p_sin)):
m_ind = int(m[o])
n_ind = int(n[o])
strg = (strg + 'P(' + f'{n_ind}' + ',' +
f'{m_ind}' + ')=' +
'{:7.4f}'.format(p_sin[o]) + '; ')
# Ionosphere
self.strg = (strg + '\n'+
'Sum VTEC=' +
'{:6.3f}'.format(vtec) +
'[TECU]' + ',' + ' sf=' +
'{:6.3f}'.format(sf) +
',' + 'STEC=' +
'{:6.3f}'.format(stec) +
'[TECU]' + '\n' +
'SSR_VTEC: SV' + ID +
' Have SSR VTEC Iono slant influence: ' +
'{:6.3f}'.format(stec) + '[TECU]' +
'{:6.3f}'.format(self.stec_corr_f1) +
'[m-L1]')