Mobile Tracking Principals

Tuesday , 31, December 2013 Leave a comment

Systems Developed for Emergency Response Are Available for Tracking Smartphones. GPS tracking, cell phone GPS and mobile phone GPS track applications are unquestionably drawing focus from consumers, mobile phone companies and software makers. The current smartphones include GPS location attributes to track cellphone location.
 Phone Tracker
GPS receivers, no matter whether in a cell phone, or simply a specific Portable gps tracking system, determine specific location by accurately timing the signals passed on by GPS satellites. This information contains the time the message was sent, exact orbital details (technically referred to as the ephemeris), plus the basic system state and calculated orbits of all GPS satellites (technically 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 finding GPS satellite signals. This delay can be caused when the GPS smartphone has been unused for days or weeks, or has been moved a significant distance while turned off 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 acquire signals and calculate initial location faster.
GPS Hot Start means whenever the GPS enabled cell phone retains its last identified position, the satellites that had been in range before, and also the almanac data in memory, and makes an attempt to obtain the same satellites and determine a fresh location based upon the previous data. This is generally 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 is when the GPS enabled cell phone remembers its last calculated location, and almanac used, but not which satellites were in view. It resets and attempts to obtain satellite signals and calculates a brand new position. The GPS receiver narrows the choice of which satellites tolook for because it stored its last known location and also the almanac data helps determine which satellites are visible in the sky. The Warm Start will need longer than the Hot Start but not as long as a Cold Start. With GPS Cold Start, the device deletes all the previous information, and attempts to locate satellites and accomplish a GPS lock. This normally takes the longest since there is no known reference data. The GPS enabled cell phone receiver must try to lock onto a satellite transmission from any available satellites.
So as to have better GPS lock times cellphone manufacturers and telco operators designed Assisted GPS technology. It downloads the ephemeris helping triangulate the mobile phone basic location. GPS Receivers can get a faster lock in exchange for a few kilobytes of data transmission. Assisted GPS, also referred to as A-GPS or AGPS, improves the performance of normal GPS in smartphones connected to the cell network. In the United States Sprint, Nextel, Verizon Wireless, and Alltel all use AGPS. Which is a means of using the cellular network to speed up finding of GPS satellites.
A-GPS assists location tracking functions of mobile phones (and other connected devices) in a couple of ways:
One way is by helping to obtain a more rapid “time to first fix” (TTFF). Assisted GPS receives and archives data in relation to the location of satellites using the cell network and so the position data does not need to be downloaded from the the satellite.
The second approach is by helping position handsets when GPS signals are weak or not available. Because GPS satellite signals may be interfered with by tall structures, and do not pass through building interiors well Assisted GPS employs distance to cellular towers to approximate location when GPS signals are not obtainable.
In the event that satellite signals are not readily available, or accuracy is less important than battery life, employing Cell-ID is a useful alternative to GPS cell phone tracking. The position of the handset may be computed by the cellular network cell id, which pinpoints the cell tower the phone is connected to. By knowing the position of this tower, you’ll be able to know approximately the location where the device might be. But, a tower can cover a huge area, from a few hundred meters, in higher populationdensity regions, to a few miles in lower density regions. This is the reason location CellID accuracy is less than than GPS accuracy. Nonetheless location from CellID still supplies a really 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 determine the time it takes signals traveling from the phone to no less than three cell towers to calculate location.