Tag Archives: PPP
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GNSS: Triple-frequency Constellations
Triple-frequency observations for high-accuracy positioning has been studied for years. It’s proven to greatly improve RTK performance (fix rate, reliability, and precision) in challenging scenarios for dual-frequency RTK, for example with a very a long base line, very active ionospheric motion, and a severe multi-path environment. Triple-frequency observations also help shorten PPP convergency time significantly....
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Inexpensive Does Not Mean Cheap
A revolution is happening in affordable surveying and geospatial instruments and solutions: high-precision positioning has become much more accessible and affordable for existing and emerging end-user constituencies. Many folks may have found high-precision prohibitively expensive in the past or were resigned to low-precision choices, but now there are a lot more solution developers, manufacturers, and...
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GPS Week Rollover – Don’t Panic (Update 3/28/19)
Updated March 28th, 2019: Unavco, the science cooperative that supports such projects as the Earthscope PBO GNSS and geophysical senor arrays, has launched a comprehensive WNRO page that addresses many of the receiver types they have deployed and includes some of their own tests. Updated March 26th, 2019: Trimble and Topcon have added updates to...
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Fire, Ice, and Latitude in Ecuador
A team of U.S. surveyors visited Ecuador to use real-time PPP to pay homage to the 18th-century “Geodesic Mission to the Equator,” one of the most difficult and significant missions in the history of surveying and geodesy. Pictured above: The team of U.S. surveyors on the 2017 Ecuador visit (from back to front): Rich Leu, John...