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Guidelines for Real-Time Kinematic (RTK) Surveying

Over the past decade Real Time Kinematic, RTK surveying  with Global Navigation Satellite Systems (GNSS) has become common practice in geomatics.RTK Surveying with Global Navigation Satellite Systems (GNSS)

RTK surveying is a relative positioning technique which measures positions using two GNSS antennas in real time. One is setup on a static point with fixed coordinates and is known as the base station. It uses a high frequency radio to transmit its raw observations to the second unit (known as the rover) and then the rover uses both observations to compute a position relative to the base location in real-time. RTK surveying requires reliable communication between base and rover units and works best with short baselines as the precision of RTK measurements decreases as the baseline length increases.

Guidelines for Real-Time Kinematic – RTK Surveying

Real Time Networks have been developed as a method of extending range limitations between base-to-rover. RTNs make use of a several base stations together to collect GNSS observations that can be used with a rover to compute a position relative to the network solution in real-time. During the last few years more public and private RTNs have been rapidly increasing, providing larger coverage zones (mostly in higher populated regions). However due to the size of Canada and the availability and extent of RTN zones, RTK surveying remains to be the viable option in GPS surveying.RTK Surveying in Canada

Both RTK & RTN GNSS surveying can allow people to achieve relative positioning with centimetre (cm) precision, however there are several important factors that need to be considered and thus a need for a good guide of best practices (equipment calibration, errors, multipath, geometry, etc.). Therefore Natural Resources Canada (NRCan) put together a group of exports from various departments that came together to publish a new set of guidelines for RTK / RTN GNSS surveying in Canada in order to better assist the surveying community and the growing geomatics industry in Canada. Their goal was to provide the industry with a set of concise and easy to follow best practice guidelines that when followed can help users achieve centimetre level RTK/RTN survey accuracy.

You can download the 29 page PDF document with this link

http://www.nrcan.gc.ca/sites/www.nrcan.gc.ca/files/earthsciences/pdf/Canada-RTK-UserGuide-v1_1-EN.pdf

Public Real Time Networks in Canada for RTK Surveying

[Article original published: Aug. 2013]



Post Update:
Since publishing this info last year, I have come across some other similar documents about RTK GNSS surveying from various other sources and have included the links to them below.


Trimble GPS Planning Software

GPS Planning Software allows you to optimize your Survey

After working on many different projects with various companies and partners, it still amazes me how many people do not consult with the latest GPS Almanacs and GPS Planning Software for planning GPS Missions prior to heading out to survey or collect GPS data. Especially for more precise GPS work and we all know how projects these days continue to demand better accuracy as technology evolves.

GPS planning softwareThere is a handy little FREE GPS Planning Software package for planning of GPS Missions provided by Trimble that we use, and is available to download free from their website. This powerful little GPS uttility can run from your laptop or PC allowing you to analyis GPS coverage for any given day helping you to determine visibility for GPS, GLONASS, IGSO and geostationary satellites. When you know what times of day have the best optimal GPS coverage then you can better plan the rest of your survey work.

The GPS Planning Software allows you to optimize your base destination region with multiple station locations allowing you to determine where it would be best to record observations, determine elevation masks, generate graphs showing satellite coverage, DOP coverage, and create sky plots of GPS satellites.

When you use the planning software you have to remmber to download the latest GPS almanac because unlike your GPS equipment, your PC will not automatically update itself with the latest Ephemeris Data. Trimble also helps out by providing this information for you on their website, but it is also provided on various other GPS related websites as well.

http://www.trimble.com/gnssplanningonline/#/Settings

 

[Update – Trimble now offers an online version]

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