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Positioning Application: Is it possible to log code or carrier phase data?

Environment/Versions
  • PosApp (SimGEN / SimREPLAYplus / SimREPLAY)
Answer
  • No - Code and Carrier Phase data cannot be logged directly with any of the data output features available in PosApp.
     
  • However you can derive the phase from
    • "Pseudorange" (PR) data for Code Phase; which is available from bulk logging, quick-look data and datastreaming
    • "Pseudorange Carrier" (PRC) data; which is available in quick-look data only

For Code Phase

  1. Work out the length of a code chip
        - e.g. GPS L1 C/A code rate = 1.023Mcps => (speed of light / code rate) = 299792458 / 1023000 = 293m
  2. Use PosApp to log the PR data
        - SimGEN users have access to all three methods
        - SimREPLAYplus and SimREPLAY users only have access to bulk log data
  3. Divide the PR data by the code chip length, e.g. 25519845 / 293 = 87098.4471
  4. The code phase is the fractional remainder, i.e. in this example, 0.4471 of a code chip
        - Convert this to degrees (*360) or radians (*2pi) as preferred
     

For Carrier Phase

  1. Work out the carrier wavelength
        - e.g. GPS L1 freq. = 1575.42MHz  => (speed of light / carrier freq) = 299792458 / 1575420000 = 0.19m
  2. Use PosApp to provide the PRC data
        - Only SimGEN users have access to quick-look data
  3. Divide the PRC data by the wavelength, e.g. 25519845 / 0.19 = 134314973.6842
  4. The carrier phase is the fractional remainder, i.e. in this example, 0.6842 of a carrier cycle
        - Convert this to degrees (*360) or radians (*2pi) as preferred

Product : SimREPLAYplus,SimREPLAY,SimGEN,PosApp