NAVICALMANAC
Decoded NavIC Almanac
|
Platform: |
OEM719, OEM729, OEM7500, OEM7600, OEM7700, OEM7720, PwrPak7, CPT7, CPT7700, SMART7 |
This log contains the decoded NavIC almanac parameters from NavIC navigation messages. Multiple messages are transmitted, one for each satellite ID with data.
The OEM7 family of receivers automatically save almanacs in their Non-Volatile Memory (NVM), so creating an almanac boot file is not necessary.
Message ID: 2122
Log Type: Asynch
Recommended Input:
log navicalmanaca onchanged
ASCII Example:
#NAVICALMANACA,COM1,4,69.5,SATTIME,1943,158160.000,02000020,fb6e,32768;919,0.001982212,86400,0.075264303,8.457495146e‑10,6493.383789062,1.327344662,2.996060720,2.542881375,-0.000580788,7.275957614e‑12,6,0,0,5*05cfbc62
#NAVICALMANACA,COM1,3,69.5,SATTIME,1943,156276.000,02000020,fb6e,32768;919,0.001962662,0,0.509411950,2.742971399e‑10,6493.538574219,1.844826864,3.107479183,-3.001633760,‑0.000161171,-5.093170330e‑11,4,0,0,7*8fbd9e3a
#NAVICALMANACA,COM1,2,69.5,SATTIME,1943,158148.000,02000020,fb6e,32768;919,0.001979351,86400,0.499982612,2.400099974e‑10,6493.359375000,-1.300198895,‑3.061969089,0.047002130,0.000025749,-3.637978807e‑12,5,0,0,5*be12ffa2
#NAVICALMANACA,COM1,1,69.5,SATTIME,1943,157620.000,02000020,fb6e,32768;919,0.001854897,86400,0.509561753,1.371485699e‑10,6493.388671875,1.842267109,3.032190537,2.385950946,0.000114441,-5.456968211e‑11,2,0,0,5*b64cf69c
#NAVICALMANACA,COM1,0,69.5,SATTIME,1943,156804.000,02000020,fb6e,32768;919,0.000161171,86400,0.076541746,1.142904749e‑09,6493.613281250,1.349937548,0.783248119,0.142653098,0.000204086,-8.003553376e‑11,7,0,0,7*495808b9
The speed at which the receiver locates and locks onto new satellites is improved if the receiver has approximate time and position (SETAPPROXTIME and SETAPPROXPOS), as well as an almanac. This allows the receiver to compute the elevation of each satellite so it can tell which satellites are visible and their Doppler offsets, improving Time to First Fix (TTFF).
|
Field |
Field Type |
Description |
Format |
Binary Bytes |
Binary Offset |
|---|---|---|---|---|---|
|
1 |
Log header |
NAVICALMANAC header For information about log headers, see ASCII, Abbreviated ASCII or Binary. |
- |
H |
0 |
|
2 |
WNa |
Week number for the almanac since the NavIC system time start epoch (August 22nd 1999) |
Ulong |
4 |
H |
|
3 |
Ecc |
Eccentricity (dimensionless) |
Double |
8 |
H+4 |
|
4 |
Toa |
Time of Almanac (s) |
Ulong |
4 |
H+12 |
|
5 |
I0 |
Inclination angle (radians) |
Double |
8 |
H+16 |
|
6 |
OmegaDot |
Rate of RAAN (radians/s) |
Double |
8 |
H+24 |
|
7 |
RootA |
Square root of semi-major axis (sqrt(m)) |
Double |
8 |
H+32 |
|
8 |
Omega0 |
Longitude of ascending node (radians) |
Double |
8 |
H+40 |
|
9 |
Omega |
Argument of perigee (radians) |
Double |
8 |
H+48 |
|
10 |
M0 |
Mean Anomaly (radians) |
Double |
8 |
H+56 |
|
11 |
Af0 |
Clock bias A0 (s) |
Double |
8 |
H+64 |
|
12 |
Af1 |
Clock Drift A1 (s/s) |
Double |
8 |
H+72 |
|
13 |
AlmSVID |
PRN ID for Almanac |
Ulong |
4 |
H+80 |
|
14 |
InterSigCorr |
Inter Signal Correction (s) |
Ulong |
4 |
H+84 |
|
15 |
Spare |
Ulong |
4 |
H+88 |
|
|
16 |
PRN |
Transmitting Satellite Identifier |
Ulong |
4 |
H+92 |
|
17 |
xxxx |
32-bit CRC (ASCII and Binary only) |
Hex |
4 |
H+96 |
|
18 |
[CR][LF] |
Sentence terminator (ASCII only) |
- |
- |
- |