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 Technology&more

With the advances of RTK, are the days of post processing 

coming to an end? According to surveyors in the field, 

apparently not. 

W

e’ve heard the stories from the early days of 
GPS: Surveyors endured long days of fieldwork 
followed by longer nights of downloads and 

processing, only to discover the need to redo a day’s work. 
Frustrating? Very. The payoff came with massive increases 
in productivity and precision compared to the optical 
methods of the day. But in order to reap the benefits 
of GPS, data processing was a necessary—sometimes 
painful—fact of life. The industry was ripe for change, 
and surveyors eagerly embraced the arrival of real-time 
kinematic (RTK) methods, which led many to predict a 
rapid end for post processing. But in spite of widespread 
use of real-time techniques, post processing continues to 
play an important role in GNSS surveying.  

The key lies in choosing the appropriate technique, and in 
understanding how post processing contributes to pro-
ductivity in both field and office. When setting up large 
or long-term projects, it’s common to establish a refer-
ence frame for positioning. Surveyors place points where 
needed to supply control for subsequent surveying using 
both RTK and optical approaches. These local networks 
are often built using short, internal baselines combined with 
ties to more distant control points. This provides internally 
consistent control across the project. Static GNSS with 
post processing provides robust results and high con-
fidence and is the usual tool of choice for this work. 
Even in small or shorter-term projects, post processing 
delivers important benefits in precision and accurate 
georeferencing. 

Tools for the Job
With the decision to use post processing in place, sur-
veyors develop their strategy for data processing.  The 
options include processing data in-house or accessing an 
online service such as the U.S. National Geodetic Survey 
(NGS) Online Positioning User Service (OPUS) system or 
the Trimble CenterPoint™ RTX™ Post-Processing Service. 
Each option has important benefits. 

The Convenience

of Precision

technology&more

technology&more

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Utilities surveyor collects data using RTK. RTK inFill  and post processing 
provides the highest flexibility in the field.

A Trimble R7 GNSS collects static data for for post processing. The Trimble 
Zephyr™ GNSS geodetic antenna helps mitigate multipath.