Mobile phone GPS is what consumers generally think about whenever checking out tracking smartphones. GPS (Global Positioning System) using satellites is the most well-known and more precise technology of tracking. Yet, GPS demands satellites to be in direct line of site from the handset. It doesn’t work really well indoors or in dense cities. If the handset is in a building, for example your school, mall, or often sitting in an automobile the signals might not get to the smartphone. Occasionally heavy cloud cover and dense foliage impedes with reception. Some mobile phones can hold on to the last identified GPS position, others may not.
Much of the discussion surrounding cell tracking, mobile GPS and cell phone tracking software could be helped by a GPS Satellite primer.
GPS satellites broadcast signals from space that GPS receivers use to determine 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 made up 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 make an orbit twice a day. They are not geostationary, they travel at over 7,000 mph. GPS satellites are solar powered but have battery reserve 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 last about ten years until all their fuel is exhausted.
GPS Satellites are not communications satellites. Geostationary or communications satellites are at a much higher orbit of about 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 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 maintain position. This is just about 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 is comprised of 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 functioning to specification and the data they send to earth is accurate.
The GPS User Segment consists 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 sometimes take longer to become ready to use after being turned on because it must acquire some basic information in addition to finding GPS satellite signals. This slow start can be caused when the GPS mobile phone has been unused for days or weeks, or has been moved a far 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 signals and determine initial location faster.
If satellite signals are not accessible, or accuracy and precision is less important than life of the battery, employing Cell-ID is a viable alternative 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 cell phone is using. By understanding the position of the tower, you’ll be able to know approximately the location where the device is. However, a tower can cover a massive area, from a couple of hundred meters, in higher populationdensity locations, to a few kilometers in lower density areas. For this reason location CellID accuracy is less than than GPS accuracy. Nonetheless monitoring from CellID still can provide a very helpful alternative.
A Quick Introduction To Smartphone GPS Tracking
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