Cell Phone Tracker Principals

GPS tracking, cell phone GPS and mobile phone track tools are really gaining notice from potential buyers, phone companies and software creators. The up-to-date mobiles include GPS position features to track cellphone position.

GPS receivers, irrespective of whether inside a mobile phone, or a specific Portable gps tracking system, calculate specific location through accurately timing the signals transferred by GPS satellites. This critical information comes with the moment the message was transmitted, highly accurate orbital details (formally referenced as the ephemeris), plus the general system state and approximated orbits of all GPS satellites (technically referred to as the almanac). GPS receivers sometimes take a long time to become ready to navigate 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 mobile phone has been turned off for days or weeks, or has been moved a far 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 determine initial position faster.

GPS Hot Start describes when the GPS enabled handset keeps its last identified position, the satellites that had been in range at the time, as well as the almanac data in memory, and tries to lock onto 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 switched off. GPS Warm Start describes 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 tries to connect to satellite signals and computes a brand new location. The GPS receiver narrows the choice of which satellites tolook for because it kept its last known location and also the almanac data helps determine which satellites are visible in the sky. The Warm Start will need longer compared to Hot Start but not as much as a Cold Start. With GPS Cold Start, the device deletes all the previous information, and tries to locate satellites and obtain a GPS lock. This takes more time since there is no known reference information. The GPS enabled handset receiver has to try to lock onto a satellite signal from any accessible satellites.

As a way to get better GPS lock times cellular manufacturers and system operators developed Assisted GPS technology. This downloads the ephemeris and helps triangulate the smartphone basic location. 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, enhances the performance of standard GPS in handsets connected to the cell network. In the United States Sprint, Nextel, Verizon Wireless, and Alltel all use A-GPS. This is a method of utilizing the cellular network to accelerate acquisition of GPS satellites.

A-GPS improves location tracking performance of cell phones (and also other connected devices) in two ways:

The first method is by assisting to get a more rapid “time to first fix” (TTFF). AGPS acquires and stores information in relation to the location of satellites using the cellular network and so the location data does not need to be downloaded from the the satellite.

Another way is by helping position handsets when GPS signals are weak or impeded. Because GPS satellite signals may be impeded by tall buildings, and do not go through building interiors well Assisted GPS makes use of distance to cellular towers to estimate position when GPS signals are not accessible.

When satellite signals are not obtainable, or accuracy and precision is less important than battery life, applying Cell-ID is a viable substitute to GPS cell phone tracking. The location of the cell phone might be determined by the cell network cell id, that pinpoints the cell tower the cellphone is connected to. By understanding the position of this tower, you may know approximately where the mobile phone will be. But, a tower can cover a large area, from a couple of hundred meters, in higher populationdensity zones, to a few miles in lower density regions. This is why location CellID precision is less than than GPS accuracy. Nonetheless tracking from CellID still supplies a really helpful alternative.

Another way of determining handset location is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation uses signal analysis data to determine the time it takes signals traveling from the phone to at least 3 cell towers to judge position.

Cell Phone Tracker Principals