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Doc ID: FAQ10365
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Positioning Application: What is the format of the Galileo nav data binary symbols dump files?
PosApp (SimGEN / SimREPLAYplus / SimREPLAY)
Galileo navigation data
Go to menu [Options-->General Options]
Enable "Dump navigation data"
Run the scenario (normal speed or turbo speed)
There are two open service binary symbols files produced by PosApp:-
A decoder utility is not provided with PosApp since the data is equivalent to the 'standard' Galileo nav data binary dump files, for which a nav data decoder utility is provided.
Any suitable binary file editor will enable you to view the content of the symbols files.
However, to decode the content of these binary symbols files the following information is of benefit:
The data is in hex characters which are written as pairs, e.g. the 6 characters = FFB52C would appear as 3 character pairs = FF B5 2C.
Each hex character is of course equivalent to 4 symbols, e.g. 580C = 0101 1000 0000 1100.
The format =>
- Time into run (4 bytes)
- Satellite ID (1 byte)
- Nav symbols for a full page of data (i.e. Odd + Even page types), 500 symbols in 63 bytes (last four bits are unused).
The symbols are in broadcast sequence such that the MSB in the first symbol data byte is the first to be transmitted and the LSB is the 8th symbol to be transmitted and so on.
The first byte in a page will always be 58 (hex) as it contains the first 8 symbols of the I/NAV sync field (0101100000)
The time stamp is a four byte field which is little endian, i.e. the LSB comes first, so “01 00 00 00” equates to 1s into the run. This parameter is two’s complement but will only be negative for E1B right at the start of the run.
Note that the start of the file will contain several consecutive pages of data for each satellite, but then changes to a sequence with one full page (odd+even) per satellite.
Product : Nav Data Decoder,SimREPLAYplus,SimREPLAY,SimGEN,PosApp,Navigation Data,Galileo