Abstract

Paper
A Field Guide for Real Time GNSS Positioning
Track: Technology
Authors: William Henning

Geospatial professionals use Real Time GNSS (RT) technology because it's a fast, efficient (labor saving) positioning tool that can yield precise and accurate coordinates when the correct methods and knowledge are applied in the field. Besides the traditional users of highest accuracy data, such as Surveyors, engineers, geodesists and other scientists, a plethora of other areas are coming on line with the need for high accuracy real time data. These include precision agriculture, machine guidance, navigation, deformation modeling, geophysical monitoring, weather service atmospheric conditions, and of course many GIS coverages.
But, how good do you feel about the data you are collecting with your real time gear? It is all "black box" technology after all. Are the data collector position quality values displaying precision or are they displaying accuracy and at what confidence level? What position deltas would you expect if you get another shot at a different time or with different weather? What are the factors that might be affecting your data, anyway? Would it be better to use your own base station or one of the real time networks (RTN) sweeping the country to get your data? Is there any way to have real confidence with a RT established position? As we can see, there are a lot of questions with this technology and the answer to all of them is: "It depends". That's why NOAA's National Geodetic Survey (NGS) has released a set of single base RT user guidelines and is working through draft RTN guidelines for administrators and users alike. This workshop will discuss how you can have real confidence with real time work and go over the important criteria for the surveyor to achieve successful field campaigns based on the guidelines. Topics of discussion for best methods for the field include: constraining local monumentation, dilution of precision values (DOP), weather conditions, data collection parameters, multipath, how RT works, how RT doesn't work, and many others emphasizing the attendees' area of interest.