What is GPS and UTM and how do they work? K. Michalski

Introduction to GPS and UTM GPS ► a satellite-based navigation system made up of 24 satellites placed into orbit by the US Department of Defense

Introduction to GPS and UTM GPS ► Originally designed for military applications, the US government made the system available to civilians in the early 1980’s.

Introduction to GPS and UTM GPS ► GPS satellites circle the earth twice a day in a particular orbit and transmit signals to GPS receivers. ► Triangulation is used to calculate a user’s exact position.

Introduction to GPS and UTM GPS ► Using four or more satellites, the GPS receiver can determine a user’s 3D motion such as latitude, longitude, and altitude.

Introduction to GPS and UTM UTM ► UTM is a meter-based global coordinate system developed by the US in World War II. ► It works like latitude and longitude system but is easier to convert.

Introduction to GPS and UTM UTM ► The UTM system is always measured in meters. ► There are 60 UTM Zones, each covering 6 degrees longitude from east to west.

Introduction to GPS and UTM UTM ► There are 10 Zones in the Continental United States. ► Maps are on a grid system and positions are defined by the UTM Zone.

US UTM Zones

Introduction to GPS and UTM UTM ► The X-coordinate is called the Easting (in meters from western edge of zone) ► The Y-coordinate is called the Northing (in meters from the equator)

Let’s review ► Where were GPS and UTM first developed and used? ► What are some applications for GPS? ► How many satellites are needed to get a good location? ► What advantages does UTM have over latitude and longitude?

Introduction to GPS and UTM UTM ► An example of a location in Wisconsin UTM Zone 16 Easting: Northing: