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jtec / prx

MIT License
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Feature request: Parsing android raw measurements and navigation messages #86

Open Raviu56 opened 5 months ago

Raviu56 commented 5 months ago

I think it'd be great if prx can directly parse Android Raw measurements for pr/doppler/cp/cn0 logs, and Android navigation messages for ephemeris on supported phones. Many new mobile phones now support nav messages too, which can be logged using GnssLogger App. Parsing this data directly from GnssLogger App .txt log is important, as GnssLogger miss some info when it logs rinex obs file - for example logging only dual band on triple band phones. Also, I found no lib until now that parses android navigation message from logs.

I would be opening similar issue in https://github.com/geospace-code/georinex too, but I think it's more related to prx than georinex

jtec commented 5 months ago

@Raviu56 Thanks for your feature request! Do you know of a way to convert those .txt log to RINEX?

Raviu56 commented 5 months ago

Yes, many are there even gnsslogger from google supports rinex, but:

  1. Only observation rinex output is supported by the tool/libraries
  2. No rinex navigation processing from supporting phones
  3. The tools/libraries miss triple frequency support for Xiaomi 11 for Beidou for example ; You can follow here https://github.com/google/gps-measurement-tools/pull/47
    1. By experiment, converting to rinex causes loss of accuracy usually, the raw numbers can be more accurate. Multiplying integer nanos by speedoflight/nanosecond is more accurate than converting it to float seconds and then to psuedorange as most of the converting tools do.