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tomojitakasu / RTKLIB

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Ublox SNR values in 2nd decimal places #253

Open dgsahan opened 7 years ago

dgsahan commented 7 years ago

Hello there,

I am using Ublox M8p receiver and once I converted ubx data to Rinex using RTKCONV, It provides SNR to nearest integer. I need SNR values at least 2nd decimal place (For GNSS reflectometry)

  1. Can I change it from source code ? or
  2. Is it the value comes from Ublox receiver?

Thank you. Sahan.

cturvey commented 7 years ago

The UBX-RXM-RAW(X) packets are defined to return integers for CNO

https://www.u-blox.com/sites/default/files/products/documents/u-blox8-M8_ReceiverDescrProtSpec_%28UBX-13003221%29_Public.pdf?utm_source=en/images/downloads/Product_Docs/u-bloxM8_ReceiverDescriptionProtocolSpec_%28UBX-13003221%29_Public.pdf

https://www.u-blox.com/sites/default/files/products/documents/u-blox6_ReceiverDescrProtSpec_%28GPS.G6-SW-10018%29_Public.pdf?utm_source=en%2Fimages%2Fdownloads%2FProduct_Docs%2Fu-blox6_ReceiverDescriptionProtocolSpec_%28GPS.G6-SW-10018%29.pdf

UBX-TRK-MEAS returns fractional data for CNO, a fixed point 8.8 format as I recall, but you probably aren't going to be able to decode that message from a NEO-M8P 3.01 part.

Have you looked at what the RTCM3 MSM 1077 message reports?