Cell tracking, cell phone GPS and mobile phone tracker software packages are gaining interest from individuals, phone companies and program programmers. The current mobile phones have GPS position functions to track smartphone location.
GPS receivers, irrespective of whether in a mobile phone, or a dedicated Portable gps tracking system, determine location by accurately timing the signals transferred by GPS satellites. This information involves the time the message was transmitted, exact orbital details (formally called the ephemeris), along with the basic system state and determined orbits of all GPS satellites (technically referred to 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 is sometimes caused when the GPS smartphone has been turned off for days or weeks, or has been transported 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 find initial position faster.
GPS Hot Start means whenever the GPS enabled smartphone remembers its last known location, the satellites that had been in view before, together with the almanac information in memory, and attempts to find 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 turned off. GPS Warm Start describes when the GPS enabled mobile phone remembers its last calculated position, and almanac used, but not which satellites were in view. It resets and makes an attempt to connect to satellite signals and calculates a whole new position. The GPS receiver narrows the choice of which satellites tolook for because it saved its last known location and the almanac data helps identify which satellites are within view. The Warm Start is going to take more time than the Hot Start but not as long as a Cold Start. With GPS Cold Start, the device deletes all the previous info
rmation, and attempts to find satellites and attain a GPS lock. This normally takes longer than other methods because there is no known reference information. The GPS enabled mobile phone receiver has to try to lock onto a satellite transmission from any available satellites.
To be able to have improved GPS lock times cellular manufacturers and wireless operators developed Assisted GPS technology. This downloads the ephemeris helping triangulate the device general position. GPS Receivers will get a quicker lock in exchange for a few kilobytes of data transmission. Assisted GPS, also known as A-GPS or AGPS, increases the performance of standard GPS in smartphones connected to the cellular network. In the United States Sprint, Nextel, Verizon Wireless, and Alltel all use AGPS. This is a means of utilizing the cellular network to accelerate finding of GPS satellites.
A-GPS improves location tracking functions of mobile phones (and also other connected devices) in a couple of ways:
One way is by assisting to secure a more rapid “time to first fix” (TTFF). AGPS acquires and archives information in relation to satellite position using the cell network so the position data does not require to be downloaded from the the satellite.
A subsequent way is by assisting position handsets when GPS signals are weak or blocked. Since GPS satellite signals may be interfered with by tall buildings, and do not go through building interiors well Assisted GPS employs distance to cellular towers to calculate position when GPS signals are not obtainable.
When satellite signals are not readily available, or precision is less important than life of the battery, using Cell-ID is a viable substitute to GPS mobile phone location. The location of the device can be estimated by the cellular network cell id, which recognizes the cell tower the mobile phone is using. By knowing the position of this tower, then you can know approximately the location where the smartphone will be. But, a tower can cover a large area, from a few hundred meters, in high populationdensity areas, to several miles in lower density regions. This is why location CellID precision is lower than GPS accuracy. Having said that location from CellID still provides a very viable alternative.
Another way of determining device position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation uses signal analysis data to calculate the time it takes signals to travel from the telephone to at least three cell towers to calculate position.
Do you really know just where your Mobile Workforce or Kids are?
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