gps
Introduction to GPS
The Global Positioning System (GPS) is a network of 24 Navstar satellites orbiting Earth at 11,000 miles. Originally established by the U.S. Department of Defence (DOD) at a cost of about US$13 billion, access to GPS is free to all users, including those in other countries. The system’s positioning and timing data are used for a variety of applications, including air, land and sea navigation, vehicle and vessel tracking, surveying and mapping, and asset and natural resource management. With military accuracy restrictions partially lifted in March 1996 and fully lifted in May 2000, GPS can now pinpoint the location of objects as small as a penny anywhere on the earth’s surface.The first GPS satellite was launched in 1978. The first 10 satellites were development satellites, called Block I. From 1989 to 1993, 23 production satellites, called Block II were launched. The launch of the 24th satellite in 1994 completed the system. The DOD keeps 4 satellites in reserve to replace any destroyed or defective satellites. The satellites are positioned so that signals from six of them can be received nearly 100 percent of the time at any point on earth.GPS provides specially coded satellite signals that can be processed in a GPS receiver, enabling the receiver to compute position, velocity and time. Basically GPS works by using four GPS satellite signals to compute positions in three dimensions (and the time offset) in the receiver clock. So by very accurately measuring our distance from these satellites a user can triangulate their position anywhere on earth.GPS receivers have been miniaturised to just a few integrated circuits and so are becoming very economical. And that makes the technology accessible to virtually everyone. These days GPS is finding its way into cars, boats, planes, construction equipment, movie making gear, farm machinery, even laptop computers. This report shows the various features of GPS and the reasons why it may soon become almost as basic as the telephone.
Tutorials and Technical Information
| Aerospace Corporation | GlobalPositioning System Primer Welcome to the Global Positioning System(GPS), What is GPS?, What is Navigation?, GPS Elements, Satellites inSpace, Ground Control Stations and Receivers, How GPS Works – An AmazingSystem, Military Uses for GPS, GPS Uses in Everyday Life, GPS RelatedLinks… |
| Joe Mehaffey and Jack Yeazel’s GPSInformation | GPS information, software, hardware, reviews and more. |
| CSD | GPS Antenna PlacementAnalysis for Receivers |
| Garmin | What is GPS? |
| GPS-Wireless Newsletter | Market Analysis for the Mobile Information Professional. |
| GPS World Online | GPS News, Articles and Resources |
| Canadian Space Geodesy Forum and the University of New Brunswick | GPS ManufacturersExtensive list of GPS Receiver Manufacturers, System Integrators,Equipment Suppliers, and Service Providers |
| GPSy | GPS Resource Library Global Positioning Systems FAQs, Tutorials and Overviews, General GPSinformation |
| maps-gps-info.com | GPS – (Almost)Everything You Wanted to Know A Brief History of GPS. In the 1970s theU. S. Department of Defense (DoD) conceived the idea of GPS out of a needto accurately determine the position of ballistic missile submarines priorto launching missiles. All the old methods of determining position hadtheir flaws. Those methods were affected by atmospheric conditions,limited in range, subject to enemy jamming, or degraded by interference… |
| Northstream | Location Based Services:Considerations and Challenges (PDF) Location Based Services arealready being launched. The trend is driven by both regulation andcompetition. · Operators are currently key, but require cooperation withother players in order to be able to offer attractive LBS. · In order toremain competitive and leverage their huge investments mobile operatorsshould consider various aspects when offering LBS, including, networktechnology evolution, regulation, standardization, user acceptance, andthe availability of attractive services. · This white paper discussescurrent trends and lists the major areas for consideration to mobileoperators, when launching Location Based Services. |
| Sam Wormley’s GPSResources at ISU | GPS Resourcesextensive list of web resources. |
| Trimble Navigation | Tutorial – All About GPS This tutorial discusses how GPS works, defines differential GPS, anddescribes putting GPS to work. A good starting point for engineerslearning GPS. |
| Peter H. Dana | GPSOverview one of the best introductions to GPS on the net. |
| 1st-at-gps-tracking | GPS information, articles and resources including GPStracking, GPS,GPS mapsand trackingdevices. |
| Locationbox | Free newsletter on location based services, links to LBScompanies, … |
| GPSy | GPS Resource Library Global Positioning Systems FAQs, Tutorials and Overviews,General GPS information |
| Pickatrail | GPSWaypoints Arizona, California, Florida, New Mexico, Texas,France, … Index of Placenames Around the World, GPSFAQ. |
| RW Christie & Associates | Dedicated to Location-Enabling Businesses. We develop wireless application concepts, sourcing the best application technology to ensure rapid and profitable deployment of LEB strategies for commercial clients. We also assist technology/application providers to source strategic funding partners and to create and manage new distribution channels, focusing on Asia. |
| SamWormley’s GPS Resources at ISU | GPSResources extensive list of web resources. |
| WirelessDevNet | LBS Channel LBS News and other resources. |
GPS antenna
The global positioning system (GPS) has enjoyed increased attention being utilized in a variety of different applications requiring precise measurement of location on the surface of the earth. Signals sent from GPS satellites may be used by location measuring applications to determine latitude and longitude of a receiving device. GPS receivers are used to determine the geographic location of the receiver by receiving microwave radio signals from a group of earth-orbiting GPS satellites. The geographic location of the GPS receiver may be computed by calculating its distance from each satellite as the result of determining how long the signals take to travel from the satellite to the receiver. GPS systems need a GPS antenna for receiving radio waves from satellites in the constellation of GPS satellites. Typically, antennas used for receiving GPS satellite signals use either a microstrip antenna, patch antenna, or quadrifilar antenna element for receiving the signal that contains the GPS location determination information. Generally, a flat GPS antenna element is utilized by GPS receivers to receive the signals transmitted. In order for the GPS receiver to compute its geographic location, the antenna element of the receiver must be oriented to receive an acceptable level of the signals.
Introduction to GPS
The Global Positioning System (GPS) is a network of 24 Navstar satellites orbiting Earth at 11,000 miles. Originally established by the U.S. Department of Defence (DOD) at a cost of about US$13 billion, access to GPS is free to all users, including those in other countries. The system’s positioning and timing data are used for a variety of applications, including air, land and sea navigation, vehicle and vessel tracking, surveying and mapping, and asset and natural resource management. With military accuracy restrictions partially lifted in March 1996 and fully lifted in May 2000, GPS can now pinpoint the location of objects as small as a penny anywhere on the earth’s surface.
The first GPS satellite was launched in 1978. The first 10 satellites were development satellites, called Block I. From 1989 to 1993, 23 production satellites, called Block II were launched. The launch of the 24th satellite in 1994 completed the system. The DOD keeps 4 satellites in reserve to replace any destroyed or defective satellites. The satellites are positioned so that signals from six of them can be received nearly 100 percent of the time at any point on earth.
GPS provides specially coded satellite signals that can be processed in a GPS receiver, enabling the receiver to compute position, velocity and time. Basically GPS works by using four GPS satellite signals to compute positions in three dimensions (and the time offset) in the receiver clock. So by very accurately measuring our distance from these satellites a user can triangulate their position anywhere on earth.
GPS receivers have been miniaturised to just a few integrated circuits and so are becoming very economical. And that makes the technology accessible to virtually everyone. These days GPS is finding its way into cars, boats, planes, construction equipment, movie making gear, farm machinery, even laptop computers. This report shows the various features of GPS and the reasons why it may soon become almost as basic as the telephone.
Tutorials and Technical Information
| Aerospace Corporation | Global Positioning System Primer Welcome to the Global Positioning System (GPS), What is GPS?, What is Navigation?, GPS Elements, Satellites in Space, Ground Control Stations and Receivers, How GPS Works – An Amazing System, Military Uses for GPS, GPS Uses in Everyday Life, GPS Related Links… |
| Joe Mehaffey and Jack Yeazel’s GPS Information |
GPS information, software, hardware, reviews and more. |
| CSD | GPS Antenna Placement Analysis for Receivers |
| Garmin | What is GPS? |
| GPS-Wireless Newsletter | Market Analysis for the Mobile Information Professional. |
| GPS World Online | GPS News, Articles and Resources |
| Canadian Space Geodesy Forum and the University of New Brunswick | GPS Manufacturers Extensive list of GPS Receiver Manufacturers, System Integrators, Equipment Suppliers, and Service Providers |
| GPSy | GPS Resource Library Global Positioning Systems FAQs, Tutorials and Overviews, General GPS information |
| maps-gps-info.com | GPS – (Almost) Everything You Wanted to Know A Brief History of GPS. In the 1970s the U. S. Department of Defense (DoD) conceived the idea of GPS out of a need to accurately determine the position of ballistic missile submarines prior to launching missiles. All the old methods of determining position had their flaws. Those methods were affected by atmospheric conditions, limited in range, subject to enemy jamming, or degraded by interference… |
| Northstream | Location Based Services: Considerations and Challenges (PDF) Location Based Services are already being launched. The trend is driven by both regulation and competition. · Operators are currently key, but require cooperation with other players in order to be able to offer attractive LBS. · In order to remain competitive and leverage their huge investments mobile operators should consider various aspects when offering LBS, including, network technology evolution, regulation, standardization, user acceptance, and the availability of attractive services. · This white paper discusses current trends and lists the major areas for consideration to mobile operators, when launching Location Based Services. |
| Sam Wormley’s GPS Resources at ISU |
GPS Resources extensive list of web resources. |
| Trimble Navigation | Tutorial – All About GPS This tutorial discusses how GPS works, defines differential GPS, and describes putting GPS to work. A good starting point for engineers learning GPS. |
| Peter H. Dana | GPS Overview one of the best introductions to GPS on the net. |
| 1st-at-gps-tracking | GPS information, articles and resources including GPS tracking, GPS, GPS maps and tracking devices. |
| Locationbox | Free newsletter on location based services, links to LBS companies, … |
| GPSy | GPS Resource Library Global Positioning Systems FAQs, Tutorials and Overviews, General GPS information |
| Pickatrail | GPS Waypoints Arizona, California, Florida, New Mexico, Texas, France, … Index of Placenames Around the World, GPS FAQ. |
| RW Christie & Associates | Dedicated to Location-Enabling Businesses. We develop wireless application concepts, sourcing the best application technology to ensure rapid and profitable deployment of LEB strategies for commercial clients. We also assist technology/application providers to source strategic funding partners and to create and manage new distribution channels, focusing on Asia. |
| Sam Wormley’s GPS Resources at ISU |
GPS Resources extensive list of web resources. |
| WirelessDevNet | LBS Channel LBS News and other resources. |
GPS antenna
The global positioning system (GPS) has enjoyed increased attention being utilized in a variety of different applications requiring precise measurement of location on the surface of the earth. Signals sent from GPS satellites may be used by location measuring applications to determine latitude and longitude of a receiving device. GPS receivers are used to determine the geographic location of the receiver by receiving microwave radio signals from a group of earth-orbiting GPS satellites. The geographic location of the GPS receiver may be computed by calculating its distance from each satellite as the result of determining how long the signals take to travel from the satellite to the receiver. GPS systems need a GPS antenna for receiving radio waves from satellites in the constellation of GPS satellites. Typically, antennas used for receiving GPS satellite signals use either a microstrip antenna, patch antenna, or quadrifilar antenna element for receiving the signal that contains the GPS location determination information. Generally, a flat GPS antenna element is utilized by GPS receivers to receive the signals transmitted. In order for the GPS receiver to compute its geographic location, the antenna element of the receiver must be oriented to receive an acceptable level of the signals.