History

The Global Positioning System (GPS) is a constellation of 24 active satellites and 3 additional backup satellites. The GPS system was developed and implemented by the United States Air Force (USAF) for operational reasons, and has since become extensively adopted for individuals in the pursuit of outdoor recreation, personal vehicle navigation, and a vast array of commercial tracking, mapping, and reporting applications.

Principles

GPS works on the basic principle of triangulation (determining position by calculating the angles from which multiple signals have arrived). The GPS satellites constantly send signals down to the earth, which are received and processed by the GPS receiver, extracting latitude, longitude, altitude, direction of travel, instantaneous speed, time of day, and a list of the satellite signals received. In order to acquire location accurately, it is necessary to “see” signals from at least four satellites, although it is highly beneficial to see more than the minimum. A properly mounted GPS receiver with an unencumbered view of the horizon in all directions may see up to 12 different signals, although on normal terrain it is more common to receive signals from 6-8 satellites.

Limitations

To derive the maximum benefit from GPS tracking data, it is important to note the shortcomings of the technology. First of all, GPS signals can not penetrate dense solids such as metal and wood, so indoor use is not practical. Furthermore, due to the very low signal levels received on earth, GPS receiver units are often unable to acquire a good reading when shielded by dense foliage. For this reason, it is important to mount the GPS receiver in a location where it has the best visibility of the sky, normally on the roof of the vehicle to be tracked.

Applications

The adoption of GPS tracking solutions has become widespread in recent times, as fuel prices and other operating costs have soared. Using iTRAK, fleet managers can dispatch mobile workers more efficiently, ensure drivers adhere to authorized routes, and closely monitor the use of company assets. Some fleet managers have reported fuel savings of 40% or more by using Mobile Resource Management (MRM) technologies such as GPS.

Read more on the Benefits of GPS Vehicle Tracking.