Methods for Phone GPS Tracking and Cell Phone Location raise the question: Do you really know where they are?
Different Approaches to Being a Mobile Phone GPS Tracker Raise the Question: Do you really know where they are?
Mobile communications means more than just making a phone call while on the move. The latest mobiles have GPS locator functionality to track phone location. These features, and others such as text messaging, internet access and the capability to utilize other applications make cell phones great gadgets. But GPS satellites aren’t always available, such as when the handset is in a building such as an school, mall, or even in an automobile. That doesn’t mean smartphone tracking isn’t available, but it does mean there are other methods of being a tracker.
To track a mobile phone involves several primary methods of determining smartphone position. GPS Global Positioning System-Satellites, Triangulation, and CellID. All these technologies convert mobile phones into mobile tracking devices. These systems can be viewed as Network Based, Handset Based or a Hybrid approach. GPS location is Handset based as it requires software programs installed on the cell phone along with GPS hardware. Triangulation and CellID are Network Based as they use the equipment and information from the cellular provider. Hybrid systems combine techniques to make best use of available information and to make location phone tracking faster.
GPS on cell phones is what people commonly think of when looking at tracking mobile phones. GPS (Global Positioning System) using satellites is the most popular and more accurate technology of tracking. But GPS requires satellites to be in direct line of site of the handset.
It doesn't work particularly well indoors or in crowded cities.
If the handset is in a building, for example your school, shopping center. Some mobile phones will retain the last known GPS location, others might not.
Another issue with handset GPS location is the potential of wasting the battery. It is important to be able to remotely adjust the frequency of taking GPS position. Choosing real-time or periodic sampling affects both the accuracy of determining position as well as battery life.
GPS receivers, whether in a mobile phone, or a dedicated GPS tracking device, calculate position by precisely timing the signals transmitted by GPS satellites. This data includes the time the message was transmitted, precise orbital information (the ephemeris), and the general system condition and estimated orbits of all GPS satellites (the almanac). GPS receivers sometimes take longer 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 delay is sometimes caused if the GPS device has been unused for days or weeks, or has been moved a significant 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 capture satellite signals and determine initial location more quickly.
GPS Hot Start is when the GPS enabled handset remembers its last calculated position, the satellites that were in range at the time, the almanac data in memory, and tries to lock onto the same satellites and compute 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 is when the GPS enabled handset remembers its last known position, and almanac used, but not which satellites were in range. It resets and tries to connect to satellite signals and computes a new position.
The GPS receiver has a general idea of which satellites tolook for because it kept its last known position and the almanac data helps identify which satellites are in range. The Warm Start will take longer than the Hot Start but not as long as a Cold Start.
With GPS Cold Start, the device dumps all the previous data, and attempts to locate satellites and accomplish a GPS lock. This takes the longest because there is no known reference information. The GPS enabled smartphone receiver has to attempt to lock onto a satellite signal from any available satellites.
Assisted GPS, also known as A-GPS or AGPS, enhances the performance of standard GPS in mobile phones connected to the cellular network. It downloads the ephemeris and helps triangulate the mobile phone general position. GPS Receivers can get a faster lock at the expense of a few kilobytes of data transmission.
A-GPS improves location tracking functions of mobile phones (and other connected devices) in a couple of ways:
One method is by assisting to obtain a faster "time to first fix" (TTFF). AGPS acquires and storesdata about satellite positionvia the cellular network so the position information does require to be downloaded from the the satellite.
The second way is by assisting position devices when GPS signals are weak or blocked. As mentioned before GPS satellite signals may be impeded by tall buildings, and do not penetrate building interiors well. A-GPS utilizes proximity to cellular towers to estimate location when GPS signals are not available.
If satellite signals are not available, or accuracy is less important than battery life, using Cell-ID is a viable substitute to GPS smartphone location. The location of the handset can be estimated by the cell network cell id, that identifies the cell tower the phone is connected to. By knowing the position of this tower, then you can know approximately where the handset is. But, a tower can cover a huge area, from a few hundred meters, in high density areas, to several kilometers in lower density areas. This is why location CellID precision is lower than GPS accuracy. Nonetheless location using CellID still provides a very good substitute.
Another way of calculating 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 your phone to at least three cell towers to determine location.
To comply with Federal Communications Commission guidelines, cell phone companies must be able to provide authorities with smartphone latitude and longitude to an accuracy of 50 to 300 meters. Cell Tower Triangulation doesn’t always meet this requirement. For comparison commercially available GPS modules are able to achieve accuracy down to 3-10m. This depends upon many factors, as GPS signals are often very weak and are affected by many variables. With Mobile Location Services (MLS), the GSM cell network provider utilizes triangulation techniques to determine the position of the mobile phone, its accuracy is proven to be much worse than that of GPS. MLS is also affected by factors similar to GPS in the sense of the barriers affecting signal quality and the density of GSM towers to help in the triangulation calculation. In remote areas position accuracy may be off as much as a mile.
It may be critical to consider how GPS location software applications handle the data and controls mobile phone settings. Having real time tracking on demand, or preferring to minimize battery use and data transmission should be a minimum requirement. Typically the application determines the location with a GPS receiver and transmits the tracking data to a server through a data connection. The data connection to the server is usually made using the Internet. How often GPS samples are taken and how often and by what method the data is sent to the server impact effectiveness and costs.
Keep in mind that there is a fundamental difference between cell phone GPS Tracking and Navigation. GPS cell phone tracking is usually related to someone keeping records of either real-time or historical mobile phone location, while Navigation deals with the handset user determining how to get from point A to point B.
A really great software package that includes remote control of handset settings, and combines Cell Phone Tracking with SMS text message, Call Log, MMS multi-media message monitoring, and a web account for storage and review is PhoneBeagle.
Follow this link if you are interested in Mobile Monitoring Software compatible with BlackBerry and Android Smartphones, used or Parental Monitoring and Small Business Employee Monitoring .
Visit this link for more information regarding the latest software for
Mobile GPS .
