Geoscience 444

Practical Aspects of GPS Surveying

Photo of a geodetic benchmark in Honduras by Neal Lord

Kurt Feigl
Associate Professor
Department of Geoscience

Description of Course

Capsule statement of course

Global Positioning System surveying for field applications: Signals. Coordinate systems. Datums. Cartographic projections. Satellite orbits. Choosing hardware. Strategies for data collection and analysis. Assessing uncertainty. Geocoding satellite images. Integrating data with Geographic Information Systems. Emerging technologies.  





Number:  two (2)
7-week modular class beginning week 10.
(2.5 hours of lecture per week) x (7 weeks) + 2 x (4-hour field exercises) = 25.5 hours of instruction


GEOSCI       444-001 LEC (55572)     Pract Appl of GPS Surveying

G L E   444-001 LEC (45403)     Pract Appl of GPS Surveying     
ENVIR ST     444-001 LEC (46124)     Pract Appl of GPS Surveying     
GEOLOGY      444-001 LEC (55572)     Pract Appl of GPS Surveying     
CIV ENGR     444-001 LEC (63268)     Pract Appl of GPS Surveying    



Many disciplines studying the Earth, its environment and anthropogenic impact on them involve mapping or sampling object in the field. The Global Positioning System allows anyone equipped with a receiver (costing as little as $100) to estimate their position coordinates (latitude, longitude and elevation) to within 10 meters easily. With a more sophisticated instruments and techniques, accuracies of better than 1 cm are possible. Applications range from scientific (e.g., measuring tectonic plates as they move) to the practical (“how do I get back to where I parked my car). If students are to apply these techniques (or supervise others to do so) in tomorrow’s world, they should understand the basic technical underpinnings of GPS.


The proposed new course is complementary to, but distinct from, the following other courses, as described in the supplementary material: Geography 370, Geography 377 (Introduction to Geographic Information Systems), Geological Engineering 302 (Introduction to Electro-Optical and Microwave Remote Sensing Systems), Geological Engineering 303 (Introduction to Remote Sensing Digital Processing), Geological Engineering 304 (Remote Sensing Visual Image Interpretation). On the other hand, I could not identify any significant overlap with any courses in the undergraduate catalog for 2005-2007. In assessing overlap, it is important to distinguish between the two similar acronyms, GPS and GIS. The former stands for Global Positioning System and is the topic of the proposed course. The latter stands for Geographic Information System and is “downstream” in the flow of information.


YES, The course 444 does count towards the 34 credits of course work in Geology and Geophysics required for the major. It also counts toward the requirement of 12-15 credits of upper-level course work.


Learning Objectives

How will students be evaluated?


List of Lecture Topics click here to download PDF file with reading assignments and schedule

First Class; positioning
How does GPS work? How well does it work?
Geometry of the Ellipsoid; Geodetic Reference System; Geoid, Ellipsoid and Datum; World Geodetic System 1984; Changing Datum
Preparing for a field survey
Field Exercise 1: Point Positioning with a single receiver
Introduction to Matlab: functions, scripts, plots, etc.
Review of Linear Algebra I: Vectors; Lengths and Dot Products; Planes
Review of Linear Algebra II: Matrices and Linear Equations; Heights by least squares; weighted least squares
Choosing a surveying strategy: the tradeoff between cost and accuracy. Expectations for student projects.
Receiver position from Code Observations
Precise point positioning for stationary receiver.
Field Exercise 2: Relative Positioning with three receivers
Precise point positioning for moving receiver
Relative positioning from phase observations for stationary receiver.
Rapid Static Positioning
Review Q  & A.
Student presentations of surveying project

Description of Project

Working in teams of two, the students will use GPS receivers to perform a survey of interest to them. They will then present the results of the survey to the class in a short, 15-minute oral presentation, as a team of two. Examples of projects might include:



Strang, G., and K. Borre (1997), Linear algebra, geodesy, and GPS, xvi, 624 p. pp., Wellesley-Cambridge Press, Wellesley, MA. [$65.00]

Warning: ordering this book through the usual channels may be slow. Please allow enough time for delivery. If you are interested in taking this course, please order the book in January! You can order it directly from the publisher if you pay by check, but not credit card.


Leick, A. (2004). GPS satellite surveying. Hoboken, NJ, John Wiley.


Online Resources


Computer Aided Engineering Center

Learn about this great resource, read the policy governing its use, and activate your account

Room 1249 in Engineering Hall




Student Version

Mathworks MATLAB 7 Student Version R14 with Service Pack 3 (Student Sales Only) for Mac/Linux/Win CD. License Valid as long as the Student is a registered Student in a Degree-Granting Institution.


Google Earth Plus

Intended for personal use, Google Earth Plus is an optional, upgraded version of Google Earth available for $20. Why buy it? In addition to the basic features, Google Earth Plus includes:
To purchase Google Earth Plus, download Google Earth at . Then run Google Earth and select "upgrade" from the "help" menu.

Excel or equivalent

For manipulating data tables in Comma-Separated Values (CSV) format.

ARC GIS (optional)

Student license $100

Earth Bridge

It's a freeware (or donationware) program that listens to NMEA GPS data stream on a serial port and sends the data to a google earth .kml file along with a .net service which lets google earth know when the file is automatically updated.
Neal has tried it with the Garmin Etrex and another GPS receiver and it seems to work well with the free version of google earth.  The earth bridge software can be found at


For tagging digital photos with GPS coordinates. No need for tricky connections between the receiver and the camera. Clever!


For translating data from one format to another....

Automatic Point Positioning Service (APPS)

Estimate position for a single GPS station with sub-meter precision from a RINEX file containing (preferably dual-frequency) phase data from a geodetic - grade GPS receiver. The receiver may be moving.

Online  Positioning  User  Service (OPUS) - Static

Estimate relative position for a fixed station with with respect to several stations of the CORS network in the US. Requires a RINEX file containing dual-frequency phase data from a geodetic - grade GPS receiver. Two different solutions are offered: Static (OPUS-S) and Rapid Static (OPUS-RS).



If you own a laptop, please bring it to class on the meeting after the field mapping exercise.


If you own a digital camera with a USB cable, please bring it to class for the field mapping exercise.

GPS receivers

To be provided by the department of Geology and Geophysics in cooperation with Geological Engineering program. Click here for more information about the GPS facility.

Data Sets

UW - Madison Campus

KMZ file for Google Earth

Data files from Camp Randall for Problem Set 1

ALL data files from Camp Randall in compressed tar format 

Driving from Berekeley campus to the SFO airport

KML file for Google Earth

Trimble 4600 LS

Neal was able to automate the Trimble nav file to RINEX obs and nav files.  The converted 4600LS files are in a file called

We haven't looked to see if any of the data from the three receivers overlap.

Class Project: Presentations from Previous Years' Students


Power Point Files

Golf Distances
Bus Stops
Lake Shore Preserve
Bike Racks
Patio Bars
Steam Tunnels

KML and KMZ Files for Google Earth

Bus Stops
Bike Racks