Cell tracking, cell phone GPS and mobile phone GPS track programs are undoubtedly getting a lot of curiosity from consumers, cellphone companies and application coders. The current cell phones include GPS locator features to track cellphone location.
GPS receivers, whether or not inside a mobile phone, or simply a specific Portable gps tracking system, calculate location by way of accurately timing the signals sent by GPS satellites. This information consists of the moment the message was transmitted, exact orbital data (formally referenced as the ephemeris), and also the basic system state and estimated orbits of all GPS satellites (formally referred to as the almanac). 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 capturing GPS satellite signals. This slow start is sometimes caused when the GPS device has been unused 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 signals and determine initial location faster.
GPS Hot Start means when the GPS enabled smartphone keeps its last known location, the satellites that were in range at the time, and also the almanac data in memory, and makes an attempt to find the same satellites and calculate a brand new location based upon the previous data. This is almost always the quickest GPS lock but Hot Start only works if the phone is in the same general area as when the GPS was last turned off. GPS Warm Start describes whenever the GPS enabled smartphone remembers its last calculated position, and almanac used, but not which satellites were in range. It performs a reset and tries to connect to satellite signals and calculates a brand new location. The GPS receiver has a general idea of which satellites toseek because it stored its last known position and also the almanac data helps identify which satellites are in range. The Warm Start is going to take longer than the Hot Start but not as much as a Cold Start. With GPS Cold Start, the device dumps all the previous data, and tries to locate satellites and achieve a GPS lock. This normally takes the longest because there is no known reference data. The GPS enabled smartphone receiver must attempt to lock onto a satellite transmission from any available satellites.
To be able to get improved GPS lock times cellular phone manufacturers and system providers introduced Assisted GPS technology. It downloads the ephemeris helping triangulate the handset basic position. GPS Receivers will get a quicker lock at the expense of a few kilobytes of data transmission. Assisted GPS, also called A-GPS or AGPS, increases the performance of normal GPS in cell phones connected to the cellular network. In the US Sprint, Nextel, Verizon Wireless, and Alltel all use Assisted GPS. Which is a method of using the cell network to accelerate acquisition of GPS satellites.
A-GPS improves location tracking performance of cell phones (and also other connected devices) in a couple of ways:
The first way is by assisting to get a more rapid “time to first fix” (TTFF). AGPS receives and stores data in relation to satellite position utilizing the cellular network so the position details does not need to be downloaded from the the satellite.
The second process is by assisting locate cell phones when GPS signals are weak or blocked. Since GPS satellite signals may be impeded by tall structures, and do not penetrate building interiors well Assisted GPS employs proximity to cellular towers to calculate location when GPS signals are not available.
If satellite signals are not available, or accuracy and precision is less important than battery life, applying Cell-ID is a good alternative to GPS mobile phone location. The position of the smartphone may be approximated by the cellular network cell id, which pinpoints the cell tower the smartphone is connected to. By having the location of this tower, you may know roughly the spot where the smartphone is. Nonetheless, a tower can cover a huge area, from a few hundred meters, in high populationdensity regions, to a few miles in lower density regions. This is why location CellID precision is lower than GPS accuracy. Even so location using CellID still provides quite a useful substitute.
Another way of calculating handset location is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation makes use of signal analysis data to determine the time it takes signals traveling from the cell phone to at least 3 cell towers to estimate location.
Principals about GPS Tracker Solutions
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