How Cell Phone Tracking Works

GPS (Global Positioning System) is the U.S. 24 satellites to provide 3-D locating data to GPS receivers on Earth. The satellites are maintained by the United States Department of Defense (DoD) and were originally deployed for military applications only. In the 1980s, the U.S. Government made the decision to allow the system to be used by civilians, and has since lifted restrictions previously placed on civilian GPS accuracy.

Today, GPS is available for anyone to use and works in all weather conditions, 24 hours a day. More importantly, there are no setup charges or subscription fees required to use GPS. How Does GPS Work, All 24 GPS satellites circle the planet twice a day in a very specific orbit.

During their travels, the satellite sends signal information to Earth. A GPS receiver receives the information from all available satellites and calculates the GPS receiver’s exact location by comparing the time that a signal was transmitted by the satellite to the time the receiver receives the signal. This provides the distance that the satellite is from the receiver.

By using this difference from several satellites, the GPS receiver is able to determine the receiver’s position with a high degree of accuracy and display on a map or chart. In order to provide an accurate 2D position consisting of latitude and longitude (and to track movement), GPS receivers require at least three GPS satellites signals to be received.

If there are four or more satellites in view, then the 3D position of the GPS receiving unit (latitude, longitude, and altitude) can be determined. How Accurate is GPS, Due to the multi-channel design of today’s GPS receivers, the majority of models are very accurate (most to within 15 meters or better of accuracy).

Although better locating data is available with DGPS (Differential GPS) (accuracy to within three to five meters), this capability has not been incorporated into the majority of cell phones at the time of this writing. How Does the GPS Satellite System Work, The 24 GPS satellites orbit the Earth at a distance of approximately 12,000 miles above the planet’s surface.

They travel at speeds of approximately 7,000 miles per hour and are powered by solar energy. Each satellite has a battery backup onboard to guard against solar eclipses, and there are also small rocket boosters onboard to help correct the orbital path when required. How Does the GPS Signal Work,

There are two low power radio signals transmitted by GPS satellites that are designated L1 and L2. The L1 signal is transmitted at 1575.42 MHz (UHF) and is designed for civilian use. Since the signal travels via line of sight, it will penetrate glass, clouds, and plastic, but will be stopped by most solid objects.

The three pieces of information contained within the signal include almanac data, ephemeris information, and a pseudorandom code. The code contains an ID for the satellite transmitting the information. The ephemeris information includes the current date and time, whether or not the satellite is operating properly, and most importantly is the portion of the GPS signal used to ascertain a position. The almanac data portion of the signal informs the receiver as to the expected location of the satellite throughout the day.



Every GPS satellite sends almanac data that indicates the orbital information for both that satellite as well as the others in the constellation. What Factors Degrade the GPS Accuracy of Cell Phones, Before getting into detail on the various GPS tracking applications for cell phones, it’s first worth reviewing some of the factors that can degrade the signal accuracy throwing off the location of the phone.