Results 1 to 3 of 3

Thread: Integrating multiple NMEA streams to one COM port

  1. #1
    Variable Bitrate
    Join Date
    Jun 2005
    Location
    Michigan
    Posts
    311

    Integrating multiple NMEA streams to one COM port

    We have COM splitters for sending data from one GPS to multiple programs. What about the opposite? Two GPS units, located in different parts of the car, with a driver to sends their data to one port. Some decision making would have to be made as to which has the better data, but it doesnt seem like it would be bad at all. Any interest?
    MII-12000 / Ampie / Lilliput 7" / BU-355 / PicoPSU / uSDC
    Currently: Enjoying the setup, but always contemplating my next move...

  2. #2
    Maximum Bitrate DeltaFX's Avatar
    Join Date
    Sep 2004
    Location
    France
    Posts
    499
    If you use high precision gps, there is no need for more than one.

    with low precision gps, theorically you could compute an average position, but they update their position when they want (you may have to wait .5 sec between gps A and gps B)... So you'll need to decode lat,lon,speed,heading, and more important, timestamp from each gps, add some serious maths, then recode output into a NMEA format......

    If you're about to devellop a logic board to mix 2 lowcost gps units then you'd better have a look on "asynchronous / switched kalman filters" and build a high precision DR-proof board that would read your gps, a 2D accelerometer /gyrocompas and the speed signal from your car to output a highly reliable NMEA sentence.

    Just my 0.02€
    Now Galileo is real. Muhahahahaha :p

  3. #3
    Variable Bitrate nkotch's Avatar
    Join Date
    Dec 2005
    Location
    FL
    Posts
    412
    Really no need for it so don't waste your time on it. There was a similar thread about using multiple antennas with a GPS unit so you could do a search for that and read some of the comments. For in car use spending the time and effort to build some sort of custome hardware/software to do that won't get you much (in my opinion) and it's possible it may not even work the way you're thinking it would.
    Nick
    '99 Ford Escort ZX2 CarPC <-- RIP Feb '07

    2006 Chevy Equinox LS (Current Project)

    **VIA EPIA PD 1ghz Mobo, OPUS 150, 7" LinITX LCD touchscreen, 512 Ram, 60Gig HD, DLink Bluetooth, Belkin 802.11g wireless,

Similar Threads

  1. USB port power dies?!
    By pixelflash in forum General Hardware Discussion
    Replies: 1
    Last Post: 10-22-2007, 09:26 AM
  2. SDK commands over the serial port ????
    By tolisn in forum Road Runner
    Replies: 4
    Last Post: 12-14-2005, 12:03 PM
  3. Replies: 4
    Last Post: 07-04-2005, 04:38 AM
  4. USB Serial Port Adapter Troubles
    By bLindmOnkey in forum General MP3Car Discussion
    Replies: 0
    Last Post: 10-13-2004, 11:29 PM
  5. Via Mini-ITX Epia 5000 serial port not working
    By vash in forum General Hardware Discussion
    Replies: 2
    Last Post: 08-13-2002, 08:48 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •