GPS tracking, cell phone GPS and cell phone GPS track applications are really securing curiosity from individuals, phone companies and application designers. The hottest mobiles have GPS location functionality to track telephone position.
To help conform to Federal Communications Commission rules, cell phone companies have to be able to give authorities with smartphone latitude and longitude to an precision of 50 to 300 meters. Cell Tower Triangulation will not always satisfy this requirement. By way of comparison, commercially available GPS modules are able to acquire accuracy down to 3-10m. This is dependent on numerous factors, as GPS signals are often rather weak and are influenced by many variables. With Mobile Location Services (MLS), the GSM cellular network provider uses triangulation algorithms to try to pinpoint the position of the smartphone, its accuracy is proven to be much worse than that of GPS. MLS is also impacted by factors similar to GPS in the sense of the interference affecting signal quality and the density of GSM towers to help in the triangulation effort. In remote areas position accuracy may be off as much as a mile.
GPS Hot Start describes whenever the GPS enabled mobile phone remembers its last identified location, the satellites that had been in range at the time, as well as the almanac information in memory, and makes an attempt to lock onto the same satellites and calculate a fresh location based upon the previous data. This is usually 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 means when the GPS enabled smartphone keeps its last known location, and almanac used, but not which satellites were in range. It performs a reset and attempts to connect to satellite signals and computes a new position. The GPS receiver has a general idea of which satellites tolook for since it saved its last known position and the almanac data helps identify which satellites are within view. The Warm Start will take longer than the Hot Start although not as much as a Cold Start. With GPS Cold Start, the device dumps all the previous data, and tries to locate satellites and attain a GPS lock. This takes longer than other methods since there is no known reference information. The GPS enabled handset receiver has to attempt to lock onto a satellite transmission from any accessible satellites.
So that you can have better GPS lock times cell phone manufacturers and network operators introduced Assisted GPS technology. This downloads the ephemeris helping triangulate the smartphone general location. GPS Receivers can get a quicker lock in return for a few kilobytes of data transmission. Assisted GPS, also referred to as A-GPS or AGPS, boosts the performance of normal GPS in mobile phones connected to the cellular network. In the United States Sprint, Nextel, Verizon Wireless, and Alltel all use Assisted GPS. This is a means of using the cell network to speed up finding of GPS satellites.
A-GPS assists location tracking performance of mobile phones (and also other related devices) in two ways:
The first way will be helping to get a more rapid “time to first fix” (TTFF). Assisted GPS acquires and stores data about the location of satellites using the cellular network and so the coordinates information does not need to be downloaded from the the satellite.
The second approach is by assisting locate smartphones when GPS signals are weak or blocked. Since GPS satellite signals may be interfered with by tall buildings, and do not penetrate building interiors well AGPS utilizes proximity to cellular towers to approximate position when GPS signals are not readily available.
When satellite signals are not readily available, or accuracy and precision is less important than battery life, using Cell-ID is a useful substitute to GPS cell phone location. The position of the device may be calculated by the cellular network cell id, which identifies the cell tower the phone is connected to. By having the position of the tower, you may know approximately the spot where the cell phone is. Nonetheless, a tower can cover an enormous area, from a couple of hundred meters, in higher populationdensity regions, to several kilometers in lower density areas. For this reason location CellID precision is lower than GPS accuracy. Nevertheless monitoring via CellID still gives you a very viable alternative.
Another way of determining cell phone 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 your cellphone to at least three cell towers to determine location.