Calculating Position from Raw GPS Data (2017)
1–10 of 21 posts
Re: Calculating Position from Raw GPS Data (2017)
#2Tangentially related, here is the opensource gps software used by a lot of phones:
https://gpsd.gitlab.io/gpsd/index.html
Development primarily lead by Eric Raymond:
Re: Calculating Position from Raw GPS Data (2017)
#3A good compliment is this interactive walk-through:
Re: Calculating Position from Raw GPS Data (2017)
#4If you're interested in running some code, there's [1] which is fairly active, but as I recall is Linux only. There is also [2] which is a Matlab (or Octave) GNSS receiver implementation; quite well documented and informative. It's meant to be a companion to the author's book [3], which itself I found quite concise and approachable.
[1] https://github.com/gnss-sdr/gnss-sdr [2] https://github.com/perrysou/GNSS_SDR [3] http://gfix.dk/matlab-gnss-sdr-book/
Re: Calculating Position from Raw GPS Data (2017)
#5Also related (and fascinating) -- a homemade GPS receiver:
Re: Calculating Position from Raw GPS Data (2017)
#6If you're interested in running some code, there's [1] which is fairly active, but as I recall is Linux only. There is also [2] which is a Matlab (or Octave) GNSS receiver implementation; quite well documented and informative. It's meant to be a companion to the author's book [3], which itself I found quite concise and approachable. [1] https://github.com/gnss-sdr/gnss-sdr [2] https://github.com/perrysou/GNSS_SDR [3]…
GNSS-SDR is a decently usable software. We use it regularly in our lab with low-cost and medium cost SDRs like Pluto, USRP B series boards (modded with .5 ppm TCXOs). Configuring it for a 15 channel GPS + Galieo L1-band receiver, the CPU usage remains at 120% or so.
Re: Calculating Position from Raw GPS Data (2017)
#7Also related (and fascinating) -- a homemade GPS receiver: http://www.aholme.co.uk/GPS/Main.htm
Re: Calculating Position from Raw GPS Data (2017)
#8Triangulation -> trilateration
Re: Calculating Position from Raw GPS Data (2017)
#9Tangentially related, here is the opensource gps software used by a lot of phones: https://gpsd.gitlab.io/gpsd/index.html Development primarily lead by Eric Raymond: https://gpsd.gitlab.io/gpsd/gps-hacking.html http://www.catb.org/~esr/
gpsd is a service daemon that monitors one or more GPSes or AIS receivers attached to a host computer through serial or USB ports, making all data on the location/course/velocity of the sensors available to be queried on TCP port 2947 of the host computer.
It doesn't do much beyond multiplexing/marshalling. The actual calculations are done in the receiver.
Re: Calculating Position from Raw GPS Data (2017)
#10Also related (and fascinating) -- a homemade GPS receiver: http://www.aholme.co.uk/GPS/Main.htm
See also http://lea.hamradio.si/~s53mv/navsats/theory.html
It has to be mentioned here, this was developed in 1991-92, before everything was available online, so yeah... the guy is a genius.