Throughout this discussion consider that there is a basic difference between handset GPS Tracking and Navigation. GPS 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 mobile phone user figuring out how to get from point A to point B. Just because a cell phone has GPS doesn?t mean that it can easily be used as a navigation device. Just like cell tracking , navigation requires third-party software.
Much of the discussion surrounding cell tracking, mobile GPS and cell phone tracker 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 is an acronym for Global Positioning System and is a network that is made up 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 also known as as the GPS Constellation, and they are orbiting once every 12 hours. They are not geostationary, but rather move 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 placed 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 last about ten years until all their fuel is exhausted.
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 force of gravity and centrifugal forces are offset and are in equilibrium. This is the best location to position a stationary satellite. The earth rotates at about 1,000 miles an hour, and because of their high earth orbit the geo-synchronous satellites need to move at about 7,000 mph to maintain position. This is approximately 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 incorporates Master Control Station, an Alternate Master Control Station, and a host of dedicated and shared Ground Antennas and Monitor Stations that work together to ensure the satellites are working correctly and the information they beam down to earth is accurate.
The GPS User Segment is composed of of GPS receivers taking the shape of handsets and , laptops, in-car navigation devices and hand-held tracking units along with the people that use them, and the software applications that make them function.
GPS receivers often 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 when the GPS cell phone has been unused for days or weeks, or has been transported a significant distance while unused 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 find initial position more quickly.
In the event that satellite signals are not readily available, or accuracy and precision is less important than battery life, making use of Cell-ID is a useful alternative to GPS smartphone tracking. The position of the device can be calculated by the cellular network cell id, that determines the cell tower the mobile phone is connected to. By having the position of the tower, you’ll be able to know approximately the location where the cell phone will be. But, a tower can cover a huge area, from a few hundred meters, in high populationdensity locations, to several kilometers in lower density areas. For this reason location CellID precision is less than than GPS accuracy. Even so location from CellID still delivers quite a useful substitute.
A Quick Guide To Cell Phone GPS Tracking
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