Throughout this discussion keep in mind that there is a fundamental difference between smartphone GPS Tracking and Navigation. GPS mobile phone tracking is normally related to a third-party keeping records of either real-time or historical mobile phone location, while Navigation deals with the cell phone user figuring out how to get from point A to point B. Just because a smartphone has GPS doesn?t mean that it can easily be used as a navigation device. Just like phone tracking, navigation requires third-party software.
Much of the discussion dealing with GPS tracking, mobile GPS and cell phone track software could be helped by a GPS Satellite primer.
GPS satellites broadcast signals from space that GPS receivers use to provide three-dimensional location (latitude, longitude, and altitude) plus precise time. GPS stands for Global Positioning System and is a system that is made up of 3 main segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment is comprised of twenty-four to thirty-two satellites that orbit the earth in medium earth orbit MEO. These satellites are also known as as the GPS Constellation, and they are orbiting twice a day. They are not geosynchronous, they travel at over 7,000 mph. GPS satellites are solar powered but have battery backup for when they are on the dark side of the earth. They are positioned so that at any given time there are at least 4 satellites ?visible? from any point on earth. Small rocket boosters on each satellite keep them properly positioned. The satellites have a lifetime of about 10 years until all their fuel runs out.
GPS Satellites are not communications satellites. Geostationary or communications satellites use a higher altitude 22,300 miles above the equator. These satellites are used for weather forecasting, satellite TV, satellite radio and most other types of global communications. At exactly 22,000 miles above the equator, the earth’s force of gravity and centrifugal forces are canceled and are in balance. This is the best location to position a communications satellite. The earth rotates at about 1,000 miles an hour, and because of their high earth orbit the geostationary satellites need to move at about 7,000 mph to sustain position. This is just about the same speed as GPS satellites, but since geo-synchronous satellites are 10,000 miles further away they don?t move relative to the earth.
The GPS Control Segment is composed of Master Control Station, an Alternate Master Control Station, and numerous dedicated and shared Ground Antennas and Monitor Stations that work together to make sure the satellites are working to specification and the information they beam down to earth is accurate.
The GPS User Segment includes of GPS receivers taking the shape of cell phones and , laptops, in-car navigation devices and hand-held tracking units along with the people that use them, and the software programs that make them work.
GPS receivers, no matter if inside of a smartphone, or a spucific Portable gps tracking system, calculate specific location through process of precisely timing the signals passed on by GPS satellites. This data consists of the moment the message was sent, accurate orbital information (formally called the ephemeris), and the overall system status and estimated orbits of all GPS satellites (formally referenced as the almanac).
Another method of determining cell phone location is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation makes use of signal analysis data to compute the time it takes signals to travel from the mobile phone to no less than three cell towers to estimate position.
With Mobile Location Services (MLS), the GSM cell network provider utilizes triangulation techniques to compute the location of the device, its accuracy is proven to be less than than that of GPS. MLS is further affected by the same issues as GPS in the sense of the interference impeding signal quality and the density of GSM towers to help in the triangulation calculation. In remote areas position accuracy may be off as much as a mile.
Smartphone GPS Tracking Guide
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