GPS tracking, mobile GPS and cell phone tracker applications are really drawing attention from consumers, cell phone companies and program designers. The hottest mobiles contain GPS position capabilities to track phone location.
To conform to Federal Communications Commission rules, cellular phone companies are required to be in a position to provide authorities with handset latitude and longitude to an precision of 50 to 300 meters. Cell Tower Triangulation isn’t going to always satisfy this condition. By way of comparison, commercially accessible GPS systems will be able to realize precision right down to 3-10m. This is determined by many factors, as GPS signals tend to be quite weak and are impacted by numerous variables. With Mobile Location Services (MLS), the GSM cellular network provider uses triangulation algorithms to determine the position of the handset, its accuracy is proven to be much worse than that of GPS. MLS is also affected by the same issues as GPS in the sense of the interference affecting signal strength and the density of GSM towers to assist in the triangulation calculation. In remote areas position accuracy may be off as much as a mile.
GPS Hot Start is when the GPS enabled device remembers its last calculated location, the satellites that were in range before, and also the almanac data in memory, and attempts to obtain the same satellites and determine a fresh location based upon the previous information. This is usually the quickest GPS lock but Hot Start only works if the phone is generally in the same location as when the GPS was last turned off. GPS Warm Start means whenever the GPS enabled smartphone recalls its last calculated position, and almanac used, but not which satellites were in view. It resets and makes an attempt to lock onto satellite signals and calculates the latest position. The GPS receiver narrows the choice of which satellites tolook for because it saved its last known position and the almanac data helps identify which satellites are within view. The Warm Start will need longer compared to Hot Start but not as long as a Cold Start. With GPS Cold Start, the device deletes all the previous information, and attempts to find satellites and achieve a GPS lock. This normally takes longer than other methods because there is no known reference information. The GPS enabled device receiver has to try to lock onto a satellite transmission from any accessible satellites.
As a way to get better GPS lock times cellular phone manufacturers and wireless operators introduced Assisted GPS technology. This downloads the ephemeris and helps triangulate the device general position. GPS Receivers can get a quicker lock in exchange for a few kilobytes of data transmission. Assisted GPS, also referred to as A-GPS or AGPS, boosts the performance of standard GPS in devices connected to the cell network. In the United States Sprint, Nextel, Verizon Wireless, and Alltel all use Assisted GPS. This is a method of utilizing the cell network to accelerate acquisition of GPS satellites.
A-GPS assists location tracking functions of smartphones (as well as other related devices) in a couple of ways:
One way is by helping to get a faster “time to first fix” (TTFF). AGPS receives and archives data concerning satellite position using the cell network so the position details does not require to be downloaded from the the satellite.
Another approach is by assisting position smartphones when GPS signals are weak or impeded. Due to the fact GPS satellite signals may be interfered with by tall structures, and do not pass through building interiors well AGPS makes use of proximity to cellular towers to compute position when GPS signals are not available.
When satellite signals are not accessible, or precision is less important than battery life, applying Cell-ID is a good alternative to GPS cell phone location. The location of the cell phone can be computed by the cellular network cell id, that determines the cell tower the cell phone is connected to. By having the position of this tower, then you can know roughly where the device will be. But, a tower can cover an enormous area, from a couple of hundred meters, in high populationdensity areas, to several miles in lower density regions. This is the reason location CellID precision is lower than GPS accuracy. Nevertheless location via CellID still can provide a truly good alternative.
Another way of calculating device position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation makes use of signal analysis data to calculate the time it takes signals to travel from the phone to at least 3 cell towers to judge position.
Solutions for Cellular Telephone Tracking
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