Technology Started for Emergency Response May Be Used for Tracking Mobiles. GPS tracking, cell phone GPS and cell phone track programs are really attracting curiosity from potential customers, phone companies and program developers. The latest cell phones integrate GPS locator features to track cell phone position.
GPS receivers, whether or not inside of a handset, or perhaps a dedicated Portable gps tracking device, compute position by precisely timing the signals sent by GPS satellites. This data contains the moment the message was transmitted, exact orbital data (formally called the ephemeris), and the basic system status and rough orbits of all GPS satellites (formally referenced as the almanac). GPS receivers sometimes take a long time to become ready to use after being turned on because it must acquire some basic information in addition to finding GPS satellite signals. This slow start can be caused when the GPS smartphone 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 acquire signals and find initial location faster.
GPS Hot Start describes when the GPS enabled cell phone retains its last calculated location, the satellites that were in range at the time, together with the almanac data in memory, and attempts to connect to the same satellites and determine a new position based upon the previous information. This is generally the quickest GPS lock but Hot Start only works if the phone is in the same general area as when the GPS was last switched off. GPS Warm Start describes whenever the GPS enabled handset recalls its last known location, and almanac used, but not which satellites were in range. It resets and makes an attempt to obtain satellite signals and computes a whole new position. The GPS receiver narrows the choice of which satellites tolook for since it stored its last known position and also the almanac data helps determine which satellites are in range. The Warm Start will need more time than the Hot Start although not as much as a Cold Start. With GPS Cold Start, the device deletes all the previous data, and attempts to locate satellites and achieve a GPS lock. This will take more time because there is no known reference data. The GPS enabled smartphone receiver must attempt to lock onto a satellite signal from any available satellites.
As a way to have better GPS lock times cellular manufacturers and network operators designed Assisted GPS technology. This downloads the ephemeris helping triangulate the device general location. GPS Receivers can get a quicker lock in return for a few kilobytes of data transmission. Assisted GPS, generally known as A-GPS or AGPS, helps the performance of normal GPS in mobile phones connected to the cell network. In America Sprint, Nextel, Verizon Wireless, and Alltel all use Assisted GPS. This is a means of utilizing the cell network to accelerate finding of GPS satellites.
A-GPS improves location tracking performance of cell phones (and also other connected devices) in two ways:
The first way will be assisting to acquire a faster “time to first fix” (TTFF). AGPS acquires and archives data in relation to satellite position utilizing the cell network and so the coordinates information does not need to be downloaded via the satellite.
The next technique is by assisting locate devices when GPS signals are weak or impeded. Because GPS satellite signals may be interfered with by tall buildings, and do not go through building interiors well A-GPS uses distance to cellular towers to estimate position when GPS signals are not accessible.
In the event that satellite signals are not readily available, or accuracy is less important than battery life, employing Cell-ID is a good alternative to GPS cell phone location. The position of the smartphone might be estimated by the cellular network cell id, which recognizes the cell tower the phone is using. By understanding the position of this tower, then you can know roughly the location where the device will be. But, a tower can cover an enormous area, from a couple of hundred meters, in high populationdensity locations, to several kilometers in lower density regions. For this reason location CellID accuracy is less than than GPS accuracy. Even so monitoring using CellID still can provide a truly useful substitute.
Another method of formulating cell phone position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation utilizes signal analysis data to determine the time it takes signals traveling from your phone to no less than three cell towers to estimate position.
Options for Cellular Telephone Phone GPS Tracking
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