Low-cost RTK

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Overview

This page is an attempt at pulling together the bits and pieces necessary to actually implement an RTK-GPS receiver based on RTKLIB and the Takasu/Yasuda paper.

RTKLIB

RTKLIB: An Open Source Program Package for RTK-GPS http://gpspp.sakura.ne.jp/rtklib/rtklib.htm

Development of the low-cost RTK-GPS receiver...

Tomoji Takasu and Akio Yasuda [Project site] [Paper] [Make blog entry]

Rover

  • CPU: A couple compact options are the BeagleBoard or PandaBoard or a light weight alternative: Gumstix "Overo Earth")
  • GPS: Ublox Antares 4 either LEA-4T module or AEK-4T kit
  • Antenna NovAtel GPS-702-GG
  • Data stream: WiFi or GPRS are used in the paper, I think I will use 2m or MURS radios.

There is now a 5-series Ublox receiver that outputs raw mode, the LEA-5T. I happen to have an AEK-4T in my collection already so I will start there. I also think starting with a laptop is an easier approach than starting with a BeagleBoard.

I also have some Pacific Crest blue brick radio modems, will probably start there for the DGPS stream.

Other options for the DGPS stream would include

  1. http://www.lemosint.com/ radio vendor
  2. http://radiometrix.com/ MURS radio manufacturer

Base station

CORS data is provided via NTrip. Basically the serial data stream from a GPS Reference Station is passed over an Internet link.

They mention Network RTK, don't know what that is yet.

NTrip site
NTrip Solutions Commercial support for NTrip

External references

Paper on NTrip at Trimble site: http://trl.trimble.com/docushare/dsweb/Get/Document-171209/NTRIPabimss%20%282%29.pdf