Throughout this discussion keep in mind that there is a fundamental difference between cell phone GPS Tracking and Navigation. GPS cell tracking is usually related to a third-party keeping records of either real-time or historical mobile phone location, while Navigation deals with the cell phone user determining how to get from point A to point B. Just because a mobile phone has GPS doesn?t mean that it can easily be used as a navigation device. Just like phone tracking, navigation requires third-party software.
A lot of the discussion surrounding cell tracking, mobile GPS and mobile phone tracking software could be helped by a GPS Satellite primer.
GPS satellites broadcast signals from space that GPS receivers utilize to determine three-dimensional location (latitude, longitude, and altitude) plus precise time. GPS stands for Global Positioning System and is a system that is composed of 3 primary segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment consists of twenty-four to thirty-two satellites that orbit the earth at a height of about 12,000 miles. These satellites are referred to as the GPS Constellation, and they are orbiting twice a day. They are not geostationary, they travel at over 7,000 mph. GPS satellites are solar powered but have battery backup for when they are in the earth?s shadow. 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 flying in the correct path. 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 are parked in space 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 gravitational force and centrifugal forces are offset and are in equilibrium. This is the ideal 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 travel at about 7,000 mph to sustain position. This is approximately the same speed as GPS satellites, but since geo-synchronous satellites are 10,000 miles further away they stay in place relative to the earth.
The GPS Control Segment includes Master Control Station, an Alternate Master Control Station, and numerous dedicated and shared Ground Antennas and Monitor Stations that work together to ensure the satellites are functioning to specification and the data they beam down to earth is accurate.
The GPS User Segment is comprised of of GPS receivers taking the shape of mobile 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 sometimes take longer to become ready to navigate after being turned on because it must acquire some basic information in addition to finding GPS satellite signals. This delay can be caused if the GPS smartphone has been unused for days or weeks, or has been transported a far distance while turned off for. The GPS must update its almanac and ephemeris data and store it in memory. The GPS almanac is a set of data that every GPS satellite transmits. When a GPS receiver has current almanac data in memory, it can acquire satellite signals and determine initial location faster.
In the event that satellite signals are not accessible, or accuracy and precision is less important than battery life, applying Cell-ID is a useful substitute to GPS cell phone tracking. The location of the handset may be determined by the cell network cell id, which pinpoints the cell tower the smartphone is connected to. By having the position of this tower, you’ll be able to know roughly where the mobile phone is. But, a tower can cover a massive area, from a few hundred meters, in higher populationdensity regions, to a few kilometers in lower density zones. For this reason location CellID precision is less than than GPS accuracy. Nonetheless tracking via CellID still can provide a really viable alternative.
An Introduction To Smartphone GPS Tracking
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