Solutions Created for Emergency Response Can Be Utilized for Keeping Track of Your Kids. Cell tracking, cell phone GPS and mobile phone tracker programs are unquestionably drawing focus from consumers, cellphone companies and program designers. The most current mobile phones feature GPS location features to track cellphone position.
To help adhere to Federal Communications Commission guidelines, cell phone companies must be in a position to provide authorities with handset latitude and longitude to an accuracy of 50 to 300 meters. Cell Tower Triangulation will not always satisfy this condition. For evaluation, commercially accessible GPS modules can certainly achieve accuracy right down to 3-10m. This depends upon several factors, as GPS signals tend to be quite weak and are impacted by many variables. With Mobile Location Services (MLS), the GSM cell network provider utilizes triangulation algorithms to determine the location of the device, its accuracy is proven to be less than than that of GPS. MLS is further affected by factors similar to GPS in the sense of the interference impeding signal strength and the density of GSM towers to help in the triangulation calculation. In remote areas location accuracy may be off as much as a mile.
GPS Hot Start is the term for whenever the GPS enabled cell phone recalls its last known location, the satellites that had been in range before, together with the almanac information in memory, and tries to lock onto the same satellites and calculate a fresh location based upon the previous information. 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 refers to whenever the GPS enabled smartphone remembers its last calculated position, and almanac used, but not which satellites were in range. It resets and makes an attempt to lock onto satellite signals and calculates the latest location. The GPS receiver has a general idea of which satellites toseek since it stored its last known position and also the almanac data helps identify which satellites are within view. The Warm Start is going to take longer than the Hot Start but not as much as a Cold Start. With GPS Cold Start, the device deletes all the previous data, and tries to find satellites and accomplish a GPS lock. This usually takes more time because there is no known reference data. The GPS enabled handset receiver must attempt to lock onto a satellite signal from any available satellites.
In order to have better GPS lock times cell phone manufacturers and network operators designed Assisted GPS technology. It downloads the ephemeris helping triangulate the cell phone basic location. GPS Receivers will get a faster lock at the expense of a few kilobytes of data transmission. Assisted GPS, also called A-GPS or AGPS, increases the performance of standard GPS in cell phones connected to the cell network. In America Sprint, Nextel, Verizon Wireless, and Alltel all use Assisted GPS. Which is a means of using the cellular network to accelerate finding of GPS satellites.
A-GPS assists location tracking functions of cell phones (as well as other related devices) in two ways:
The first method is by helping to get a more rapid “time to first fix” (TTFF). Assisted GPS gets and archives information concerning satellite location via the cellular network so the location data does not need to be downloaded from the the satellite.
The other method is by assisting position handsets when GPS signals are weak or blocked. Because GPS satellite signals may be interfered with by tall structures, and do not pass through building interiors well A-GPS makes use of proximity to cellular towers to approximate location when GPS signals are not readily available.
In the event that satellite signals are not obtainable, or accuracy and precision is less important than battery life, making use of Cell-ID is a viable substitute to GPS smartphone location. The location of the cell phone can be approximated by the cell network cell id, that recognizes the cell tower the cellphone is using. By understanding the position of the tower, you’ll be able to know roughly the place that the cell phone will be. However, a tower can cover a large area, from a couple of hundred meters, in high populationdensity areas, to a few miles in lower density regions. This is why location CellID precision is lower than GPS accuracy. Nevertheless tracking from CellID still supplies a really helpful substitute.
Another way of calculating handset position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation employs signal analysis data to calculate the time it takes signals to travel from the mobile phone to at least 3 cell towers to determine location.
Smartphone GPS Fundamentals
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