Learning with GPSPresenter- Dan Careydcarey90@gmail.com

https://careywiki.wikispaces.com/August 11 and 12, 2009

Today’s GoalsLearn what is GPSHow to work with a GPS unitInitialize it, collect data, enter data, clear

data How it is used in the real world Why it is important in educationHands on practice

History of GPSGlobal

Positioning

System

Began in the 1970’s for military purposesFully operational April 1995.

How a GPS worksThree components to Global Positioning

SystemsSpace segmentUser segment – you holding the GPS unitControl segment

Space SegmentConsists of 24 to 32 satellites that orbit

earth that are sending precise radio signals to the GPS receiver

Artist Interpretation of GPS satellite, image courtesy of NASASource: http://www.navcen.uscg.gov/ftp/gps/ggeninfo/gps-iif.tif

User SegmentConsists of a GPS receiver

Can be a handheld unitIn your automobileFarm equipmentCell phone

A GPS receiver calculates its position by precisely timing the signals sent by the GPS satellites high above the Earth

Control SegmentThe flight paths of the satellites are tracked

by US Air Force monitoring stations The tracking information is sent to the Air

Force Space Command's master control station in Colorado Springs. Then contacts each GPS satellite regularly with a navigational update.

Control Segment

Space Segment

User Segment

Putting it all togetherPutting it all together

Monitor Stations

GroundAntennas

Master Station

How a GPS can be used Military. Search and rescue. Disaster relief. Surveying. Marine, aeronautical and terrestrial navigation. Remote controlled vehicle and robot guidance. Satellite positioning and tracking. Shipping. Geographic Information Systems (GIS). Recreation.

Sources of Signal InterferenceSources of Signal Interference

Earth’s Atmosphere

Solid Structures

Metal

Electro-magnetic Fields

Waypoint A waypoint is based on coordinates entered

into a GPS receiver’s memory. It can be either a saved position fix, or user

entered coordinates. It can be created for any remote point on

earth. It must have a receiver designated code or

number, or a user supplied name. Once entered and saved, a waypoint remains

unchanged in the receiver’s memory until edited or deleted.

Planning a Navigation RoutePlanning a Navigation Route

Start

= Waypoint

How A Receiver Sees Your RouteHow A Receiver Sees Your Route