GPS on cell phones is what consumers commonly consider any time taking a look at locating cell phones. GPS (Global Positioning System) utilizing satellites is the most well-known and more precise means of tracking. Still, GPS must have satellites to be in direct line of site from the smartphone. It doesn’t work as well indoors or in dense urban centers. If the smartphone is in a building, for example your school, shopping center, or often sitting in an automobile the signals may well not get to the smart phone. From time to time heavy cloud cover and heavy foliage interferes with signals. Some cell phones will retain the last identified GPS location, others might not.
Much of the discussion dealing with cell tracking, mobile GPS and mobile phone track 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 system that is composed of 3 main segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment is composed of twenty-four to thirty-two satellites that orbit the earth in medium earth orbit MEO. 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. They are solar powered but have battery backup for when they are in the earth?s shadow. They are placed so that 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 gravitational force and centrifugal forces are canceled and are in balance. This is the ideal location to place 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 travel at about 7,000 mph to maintain position. This is just about the same speed as GPS satellites, but since communications satellites are 10,000 miles further away they don?t move relative to the earth.
The GPS Control Segment is comprised 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 functioning to specification and the information they beam down to earth is accurate.
The GPS User Segment is comprised of of GPS receivers taking the shape of devices 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 function.
GPS receivers sometimes take a long time to become ready to use after it’s turned on because it must acquire some basic information in addition to finding GPS satellite signals. This delay can be caused if the GPS cell phone has been turned off for days or weeks, or has been transported 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 capture satellite signals and find initial location faster.
When satellite signals are not obtainable, or accuracy is less important than life of the battery, applying Cell-ID is a viable alternative to GPS cell phone tracking. The location of the mobile phone can be estimated by the cellular network cell id, that pinpoints the cell tower the cell phone is connected to. By knowing the location of the tower, then you can know roughly the spot where the smartphone might be. Nonetheless, a tower can cover a massive area, from a few hundred meters, in high populationdensity locations, to a few miles in lower density zones. For this reason location CellID accuracy is lower than GPS accuracy. Nonetheless monitoring using CellID still supplies a really useful alternative.
A Look At Mobile Phone GPS Tracking
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