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Nicko
16th March 2013, 01:14 PM
http://www.rtklib.com/

Overview

RTKLIB is an open source program package for standard and precise positioning with GNSS (global navigation satellite system). RTKLIB consists of a portable program library and several APs (application programs) utilizing the library. The features of RTKLIB are:

(1) It supports standard and precise positioning algorithms with:

GPS (http://www.navcen.uscg.gov/pdf/IS-GPS-200F.pdf), GLONASS (http://facility.unavco.org/kb/getattachment.php?data=NzI3fGlrZDUxZW4ucGRm), Galileo (http://ec.europa.eu/enterprise/policies/satnav/galileo/files/galileo-os-sis-icd-issue1-revision1_en.pdf), QZSS (http://qz-vision.jaxa.jp/USE/is-qzss/DOCS/IS-QZSS_14_E.pdf), BeiDou (http://www.beidou.gov.cn/attach/2012/12/27/201212273da29c5eb8274deb8cd2b178228ba2bd.pdf) and SBAS (http://www.rtca.org/downloads/DEC%202004%20-%2005-01-06.htm#_Toc92863948)
(2) It supports various positioning modes with GNSS for both real-time and post-processing:

Single, DGPS/DGNSS, Kinematic, Static, Moving-Baseline, Fixed, PPP-Kinematic, PPP-Staticand PPP-Fixed
(3) It supports many standard formats and protocols for GNSS:

RINEX 2.10 (ftp://igscb.jpl.nasa.gov/pub/data/format/rinex210.txt), 2.11 (http://igscb.jpl.nasa.gov/igscb/data/format/rinex211.txt), 2.12 (ftp://ftp.unibe.ch/aiub/rinex/rinex212.txt) OBS/NAV/GNAV/HNAV/LNAV/QNAV, RINEX 3.00 (http://igscb.jpl.nasa.gov/igscb/data/format/rinex300.pdf), 3.01 (ftp://ftp.unibe.ch/aiub/rinex/rinex301.pdf), 3.02 OBS/NAV, RINEX 3.02 CLK (http://igscb.jpl.nasa.gov/igscb/data/format/rinex_clock302.txt), RTCM ver.2.3 (http://www.rtcm.org/), RTCM ver.3.1 (with amendment 1-5), ver.3.2 (http://www.rtcm.org/), BINEX (http://binex.unavco.org/binex.html), NTRIP 1.0 (http://www.rtcm.org/), RTCA/DO-229C (http://www.rtca.org/downloads/DEC%202004%20-%2005-01-06.htm), NMEA 0183 (http://www.nmea.org/), SP3-c (http://igscb.jpl.nasa.gov/igscb/data/format/sp3c.txt), ANTEX 1.4 (http://igscb.jpl.nasa.gov/igscb/station/general/antex14.txt), IONEX 1.0 (http://igscb.jpl.nasa.gov/igscb/data/format/ionex1.pdf), NGS PCV (http://www.ngs.noaa.gov/ANTCAL) and EMS 2.0 (http://www.egnos-pro.esa.int/ems/EMS_UID_2_0.pdf) (refer the Manual (http://www.rtklib.com/rtklib_document.htm) for details)
(4) It supports several GNSS receivers' proprietary messages:

NovAtel: OEM4/V/6, OEM3, OEMStar, Superstar II (http://www.novatel.com), Hemisphere: Eclipse, Crescent (http://www.hemispheregps.com), u-blox: LEA-4T/5T/6T (http://www.u-blox.com/), SkyTraq: S1315F (http://www.skytraq.com.tw/), JAVAD: GRIL/GREIS (http://www.javad.com/), Furuno: GW-10 II/III (http://www.furuno.com/) and NVS NV08C BINR (http://www.nvs-gnss.com/) (refer the Manual (http://www.rtklib.com/rtklib_document.htm) for details)
(6) It supports external communication via:
Serial, TCP/IP, NTRIP, local log file (record and playback) and FTP/HTTP (automatic download) (7) It provides many library functions and APIs for GNSS data processing:

Satellite and navigation system functions, matrix and vector functions, time and string functions, coordinates transformation, input and output functions, debug trace functions, platform dependent functions, positioning models, atmosphere models, antenna models, earth tides models, geoid models, datum transformation, RINEX functions, ephemeris and clock functions, precise ephemeris and clock functions, receiver raw data functions, RTCM functions, solution functions, Google Earth KML converter, SBAS functions, options functions, stream data input and output functions, integer ambiguity resolution, standard positioning, precise positioning, post-processing positioning, stream server functions, RTK server functions, downloader functions
(8) It includes the following GUI and CUI APs:


Function
GUI AP
CUI AP
Notes


(a)
AP Launcher
RTKLAUNCH
-



(b)
Real-Time Positioning
RTKNAVI
RTKRCV



(c)
Communication Server
STRSVR
STR2STR



(d)
Post-Processing ****ysis
RTKPOST
RNX2RTKP



(e)
RINEX Converter
RTKCONV
CONVBIN



(f)
Plot Solutions and Observation Data
RTKPLOT
-



(g)
Downloader of GNSS Data
RTKGET
-



(h)
NTRIP Browser
SRCTBLBROWS
-




(9) All of the executable binary APs for Windows are included in the package as well as whole source programs of the library and the APs.

Michael
16th March 2013, 05:09 PM
Well, I tried to read the above post several times, & I still do not have a clue what it does.

Nicko
16th March 2013, 08:16 PM
Click on the link ;)

I don't either but it was mentioned in one of Wahroonga's threads

IainS
26th March 2013, 10:29 AM
Hmmm,

firstly it allows more precise positioning using better algorithms and using different types of GPS Satellites, secondly it seems to allow post-processing of data (this provides greater accuracy by adjusting for various errors in satellite positions) and the rest is technical stuff. Whether any of this is useful for your typical Garmin owner is hard to tell from the page which I have to say is in typical geek speak and format with a large learning curve (so typical of free software). Looking at the screens I'd say it is not for the faint hearted and if you are happy with the standard GPS error of 5m then you might want to consider other things to do with your life.

Cheers Iain

Nicko
26th March 2013, 12:42 PM
Hmmm,

firstly it allows more precise positioning using better algorithms and using different types of GPS Satellites, secondly it seems to allow post-processing of data (this provides greater accuracy by adjusting for various errors in satellite positions) and the rest is technical stuff. Whether any of this is useful for your typical Garmin owner is hard to tell from the page which I have to say is in typical geek speak and format with a large learning curve (so typical of free software). Looking at the screens I'd say it is not for the faint hearted and if you are happy with the standard GPS error of 5m then you might want to consider other things to do with your life.

Cheers Iain

The standard Garmin/tomTom/Navman street navigators cannot utilise this, however, in theory handhelds can as long as they accept corrections, such as NMEA. This program accepts inputs from various GPS constellations and GPS protocols and formats which may include dual frequency data, the same data RTK 1 cm systems use. It will then correct raw position data using algrithyms to adjust for errors to provide higher accuracy positioning.

It will then output the corrected data to a device that accepts the different protocols listed.

Raw data in > processed by an algorithym> corrected position out.

An example of the hardware would be a Dual frequency antenna and dual frequency GPS engine (receiver) (black box) that outputs the raw data it receives to a connected Laptop which the programs sits in and then output to a a transmitter that transmits either via wire or wireless (UHF, GSM network HF, WiFi etc) to a GPS device that can read said corrected data. Assuming the end GPS device can accept and display corrections own to 1cm. All handhelds (except some older ones) tend to only display accuracy to single metre digit and not sub metre. Thus, possibly you may utilise said program in the laptop as the display for correctied data as it has a GUI with various information displayed.

Typical usage:

A Base station would consist of an antenna, GPS receiver, computer, 3G modem (with GSM simcard). If you have "rovers" (mobile device) that needs better accuracy than 5 metres for, say asset collection or centering of a road via tracklogging feature.

Who would use it:

Councils, asset data collectors, water metre reading contractors, exploration companies, environmental agencies, etc etc

Costs:

Dependant upon the antenna and GPS receiving the raw data but can be anywher between say $5,000 to $20K. I know of cheap RTK antennas and boards for around $5K and give 1CM accuracy, so it's possible say a few 10s of thousands of dollars.