gpsd-dev
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: gpsprof: higher resolution


From: John Ackermann N8UR
Subject: Re: gpsprof: higher resolution
Date: Sun, 16 Aug 2020 16:56:17 -0400
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0

On 8/16/20 4:41 PM, Gary E. Miller wrote:

For the u-blox F9P: RELPOSNED is 1mm precision, and HPPOSLLH is 9
decimal degrees of precision.

For other 9-series POSLLH is 7 decimal digits of fractional degrees.

For the 9-series xxRMC is ddmm.mmmmm, which is about 6 decimal digit or
precision.

To get the most from the F9P requires binary messages, not NMEA, and
fiddling with the sentence mix.

What I'm seeing in the GGA sentence from any of the receivers that have the NMEA HIPREC config option is seven decimal places following the minute:

$GNGGA,134648.00,3943.7111969,N,08410.6922079,W,4,12,0.74,280.601,M,-33.483,M,1.0,0073*5C

which ought to translate to about 9 digits of precision. So pretty similar to the 1mm of the binary. (And it also give three decimal places or 1 mm for altitude.)

BTW, I discovered that while the only 8-series receiver to support NMEA HI PREC is the M8P, all three units of the 9 series that I've tested (M9N, M9P, and M9T) support it.

John




reply via email to

[Prev in Thread] Current Thread [Next in Thread]