Re: $GPGGA / increased number of satellites

[Hans Mayer]

On 05.05.24 21:15, Gary E. Miller wrote:

Yo Gary,

> Please post full captures.
>

What do you mean with full log ? I am running

gpspipe --nmea -u | grep --line-buffered GPGGA >> /var/log/gpsd/nmea.log &

Do you want to have the log of May 4th ?

Now I realized that the logs before the upgrade had 86400 lines +/- 1. This is one line per second. Now the files have about 10800 lines. Each night I do a logrotate.

> But, beleive the the new gpsd got smarte at decoding the data that
> you always had.
>

I am quite sure that gpsd is smart, no discussion.

> What you did not notice is that the number of satellites did not
> increase, but the number of satellite/signal pairs increased because
> u-blox had failed to document that until recently.
>     
    I didn't update ZED-F9P 


> By signal, I mean: L1, L2, L5, B2, etc.
>
> You can see this using cgps, or xgps.
>
>

Hmm ? Not sure what you mean. When I start xgps I don't see the bands.

What I see is a flickering screen which changes about twice per second.

On the bottom right corner in one screen there is sat seen: 50 and used 31, the other one say seen: 78 and used 71

But generell I see a mismatch. 

When I run gpspipe ( as described above ) I get currently about 70 satellites in the GPGGA record.

But when I use gpscsv to filter out the unique satellites I get about 49 ( in the moment )

This is the way I have done it:

mayer# gpscsv -n 10 -c SAT --header 0 | awk -F, '
BEGIN {
  GNSSID=99999 ;
  SVID=99999 ;
  PRN=99999 ;
}
{
  if ( ! ( ( $2 == GNSSID ) && ( $3 == SVID ) && ( $4 == PRN ) ) ) { print ( $2 , $3 , $4 ) }  ;
  GNSSID = $2 ;
  SVID = $3 ;
  PRN = $4 ;
}' | sort -u | wc -l
     49   

But in the past ( the time before the upgrade ) the number of both methods did match.

Kind regards

Hans

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