GPS on cell phones is what people typically think about any time checking out locating smartphones. GPS (Global Positioning System) using satellites is the most well-known and more accurate way of tracking. However, GPS requires satellites to be in direct line of site of the handset. It doesn’t work as well indoors or in dense cities. In the event that the cellular phone is in a building, for instance your school, shopping center, or often sitting in an automobile the signals may not reach the cell phone. Often heavy cloud cover and dense trees interferes with reception. Some mobile phones can hold on to the last known GPS position, others might not.
A lot of the discussion surrounding GPS tracking, cell phone 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 provide 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 made up 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 once every 12 hours. They are not geostationary, but rather move 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 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 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 gravitational force and centrifugal forces are offset and are in equilibrium. This is the best location to park a stationary satellite. The earth rotates at about 1,000 miles an hour, and because of their high earth orbit the earth-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 they 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 working correctly and the information they send to earth is accurate.
The GPS User Segment is composed of of GPS receivers taking the shape of mobiles 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 capturing GPS satellite signals. This slow start is sometimes caused if the GPS device 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 determine initial position faster.
In the event that satellite signals are not readily available, or accuracy and precision is less important than battery life, employing Cell-ID is a viable alternative to GPS cell phone tracking. The location of the device might be computed by the cellular network cell id, that determines the cell tower the phone is using. By understanding the location of this tower, you may know roughly the location where the smartphone might be. Still, a tower can cover a huge area, from a few hundred meters, in high populationdensity regions, to several miles in lower density regions. This is why location CellID precision is lower than GPS accuracy. Nonetheless location via CellID still supplies a very useful substitute.
Smartphone GPS Tracking Basics
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