mardi 7 janvier 2014

Decoded ephemeris data for Galileo PRN12, 19 and 20

Here are the decoded ephemeris data that were available the 22/12/2013 inside the Galileo I/NAV message

PRN 12 :

Word Type 1: Ephemeris (1/4)
IODnav : 63
toe : 37800
M0 : -2.368438e+000
e : 1.685068e-004
SQRT_A : 5.440594e+003

Word Type 2: Ephemeris (2/4)
IODnav : 64
Omega0 : 2.944734e-001
i0 : 9.600628e-001
omega : -1.991145e+000
i_dot : 0

Word Type 3: Ephemeris (3/4) and SISA
IODnav : 63
Omega_dot : -5.541302e-009
delta_n : 3.182633e-009
C_UC : -5.485490e-006
C_US : 9.587035e-006
C_RC : 1.343438e+002
C_RS : -1.200000e+002
SISA : 0

Word Type 4: SVID, Ephemeris (4/4), and Clock correction parameters
IODnav : 64
SV_ID : 12
C_IC : -2.235174e-008
C_IS : 6.519258e-008
t0c : 3.840000e+004
af0 : 8.443353e-005
af1 : 1.091394e-011
af2 : 0.000000e+000

PRN19 :

Word Type 1: Ephemeris (1/4)
IODnav : 174
toe : 39000
M0 : -1.075246e+000
e : 1.793728e-004
SQRT_A : 5.440594e+003

Word Type 2: Ephemeris (2/4)
IODnav : 174
Omega0 : 2.387163e+000
i0 : 9.623545e-001
omega : 1.958601e+000
i_dot : 0

Word Type 3: Ephemeris (3/4) and SISA
IODnav : 174
Omega_dot : -5.737739e-009
delta_n : 3.410856e-009
C_UC : 9.089708e-007
C_US : 4.669651e-006
C_RC : 2.407188e+002
C_RS : 1.600000e+001
SISA : 0

Word Type 4: SVID, Ephemeris (4/4), and Clock correction parameters
IODnav : 174
SV_ID : 19
C_IC : -1.862645e-009
C_IS : 3.166497e-008
t0c : 3.900000e+004
af0 : -1.240475e-005
af1 : -3.637979e-012
af2 : 0.000000e+000

PRN20 :

Word Type 1: Ephemeris (1/4)
IODnav : 392
toe : 39000
M0 : -1.070787e-002
e : 2.367625e-004
SQRT_A : 5.440594e+003

Word Type 2: Ephemeris (2/4)
IODnav : 392
Omega0 : 2.387133e+000
i0 : 9.623660e-001
omega : 1.592330e+000
i_dot : 0

Word Type 3: Ephemeris (3/4) and SISA
IODnav : 392
Omega_dot : -5.704880e-009
delta_n : 3.353711e-009
C_UC : 8.475035e-007
C_US : 5.064532e-006
C_RC : 2.343750e+002
C_RS : 1.600000e+001
SISA : 0

Word Type 4: SVID, Ephemeris (4/4), and Clock correction parameters
IODnav : 392
SV_ID : 20
C_IC : -2.607703e-008
C_IS : -1.676381e-008
t0c : 3.900000e+004
af0 : 6.250702e-003
af1 : 9.458745e-010
af2 : 0.000000e+000

dimanche 5 janvier 2014

Galileo I/NAV navigation message decoded

The SDR has been updated with deinterleaving and viterbi decoding, and the Galileo I/NAV has been successfully decoded for the PRN12 the 22/12/2013 at around 11h48.

Here are the decoded data (in the format I used, based on the ICD, some error might exist in it since I didn't completely validate the function !) :

IODa : [0 0 0 0]
alm data :
         WNa = 0
         toa = 38400
         SV_ID1 data :
                                 SV_ID1 = 0
                                 SQRT_delta_a = 5.332
                                 e = 0.020828
                                 omega = 2.0944
                                 delta_i = 0.13077
                                 Omega0 = -2.0945
                                 Omega_dot = -2.4979e-7
                                 M0 = 2.0617
                                 af0 = 0.041666
                                 af1 = 9.9317e-9
                                 E5b_HS = 3 --> indicates that signal is currently under test
                                 E1B_HS = 3 --> indicates that signal is currently under test
         SV_ID2 data :
                                 SV_ID2 = 0
                                 SQRT_delta_a = 5.332
                                 e = 0.020828
                                 omega = 0.66666
                                 delta_i = 0.13077
                                 Omega0 = -2.0945
                                 Omega_dot = 0
                                 M0 = 2.0944
                                 af0 = 0.041666
                                 af1 = 9.9317e-9
                                 E5b_HS = 3 --> indicates that signal is currently under test
                                 E1B_HS = 3 --> indicates that signal is currently under test
         SV_ID3 data :
                                 SV_ID3 = 0
                                 SQRT_delta_a = 5.332
                                 e = 0.020828
                                 omega = 2.0923
                                 delta_i = 0
                                 Omega0 = -2.0945
                                 Omega_dot = -2.4979e-7
                                 M0 = 2.0944
                                 af0 = 0.041666
                                 af1 = 9.9317e-9
                                 E5b_HS = 3 --> indicates that signal is currently under test
                                 E1B_HS = 3 --> indicates that signal is currently under test
GST-GPS :
          A0G : -2.9104e-11
          A1G : -1.7764e-15
          t0G : 0
          WN_0G : 0
IODnav = [64 64 64 64]
eph data :
          toe = 38400
          M0 = -2.2954
          e = 0.0001686
          SQRT(A) = 5440.6
          Omega_dot = -5.5349e-9
          delta_n = 3.1876e-9
          C_UC = -5.411e-6
          C_US = 9.5852e-6
          C_RC = 134.41
          C_RS = -120
          Omega0 = 0.29447
          i0 = 0.96006
          omega = -1.9911
          i_dot = 0
          SV_ID = 12
          C_IC = -2.2352e-8
          C_IS = 6.5193e-8
SISA = 0 (currently definition not available in the ICD)
iono correction :
          ai0 = 131.25
          ai1 = -1.0352
          ai2 = 0.0072937
          Region 1 = 0
          Region 2 = 0
          Region 3 = 0
          Region 4 = 0
          Region 5 = 1
BGD_E1_E5a = -1.8626e-9
BGD_E1_E5b = -1.8626e-9
E5b_HS = 0
E1B_HS = 0
E5b_DVS = 0
E1B_DVS = 0
GST :
          WN : 748
          TOW : 39115
Clock correction :
          t0c : 38400
          af0 : 8.4434e-5
          af1 : 1.0914e-11
          af2 : 0
GST_UTC :
          A0 : -2.794e-9
          A1 : 8.8818e-16
          delta_t_LS = 16
          t0t = 5.184e5
          WN_ot = 235
          WN_LSF = 158
          DN = 7
          delta_t_LSF = 16

samedi 7 septembre 2013

Preamble search results

Preamble search has been implemented and shows good results on data channel (1s interval detected between most of the peaks on 1ms and 4ms correlation results).

Secondary code search has also been tested on the pilot channel for verification.


Tracking of pilot channel (with Bump-Jump algorithme) is used to initiate the tacking on the data channel.

samedi 24 août 2013

Galileo tracking the 20/08/2013

Galileo tracking achieved the 20/08/2013 for PRN11, PRN19 and PRN20 and shows good results of the SDR as well as the shape of the Galileo message transmitted by the satellites :




Further update of the SDR will consist into de-interleaving and viterbi decoding of the bits, then decoding of the message will allow to get the navigation data.

dimanche 18 août 2013

Galileo PVT planned

Major milestones have been successfully passed on the development of the SDR allowing tracking of all Galileo satellites (some pictures will come soon).

Further development will allow to perform a PVT with the 4 current Galileo satellites before the end of this year !

mercredi 20 février 2013