Cell tracking, cell phone GPS and cell phone tracker tools are unquestionably attracting focus from potential customers, cell phone companies and software developers. The most recent smartphones have GPS location attributes to track cell phone location.
GPS receivers, whether inside a cell phone, or simply a dedicated Portable gps tracking device, compute location by precisely timing the signals transmitted by GPS satellites. This data provides the time the message was sent, accurate orbital data (technically called the ephemeris), along with the general system condition and calculated orbits of all GPS satellites (formally called the almanac). GPS receivers sometimes take a long time to become ready to use after it’s turned on because it must acquire some basic information in addition to finding GPS satellite signals. This slow start is sometimes caused if the GPS device has been turned off for days or weeks, or has been transported 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 acquire satellite signals and find initial location faster.
GPS Hot Start means whenever the GPS enabled device remembers its last identified location, the satellites which were in view at the time, together with the almanac information in memory, and tries to connect to the same satellites and determine a fresh position based upon the previous information. This is generally 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 is the term for when the GPS enabled device remembers its last known location, and almanac used, but not which satellites were in range. It resets and makes an attempt to connect to satellite signals and calculates a new location. The GPS receiver narrows the choice of which satellites toseek because it kept its last known location and also the almanac data helps identify which satellites are within view. The Warm Start will need more time than the Hot Start but not as long as a Cold Start. With GPS Cold Start, the device deletes all the previous data, and tries to locate satellites and achieve a GPS lock. This usually takes more time because there is no known reference information. The GPS enabled cell phone receiver must attempt to lock onto a satellite transmission from any accessible satellites.
In order to get improved GPS lock times cellular phone manufacturers and network operators introduced Assisted GPS technology. It downloads the ephemeris helping triangulate the handset general location. GPS Receivers can get a faster lock in exchange for a few kilobytes of data transmission. Assisted GPS, often known as A-GPS or AGPS, helps the performance of normal GPS in cell phones connected to the cell network. In the United States Sprint, Nextel, Verizon Wireless, and Alltel all use AGPS. This is a method of using the cell network to speed up finding of GPS satellites.
A-GPS assists location tracking functions of cell phones (and other connected devices) in a couple of ways:
The first method is by assisting to obtain a more rapid “time to first fix” (TTFF). A-GPS gets and archives data regarding the location of satellites using the cell network and so the position details does not need to be downloaded via the satellite.
A subsequent method is by helping position cell phones when GPS signals are weak or impeded. Because GPS satellite signals may be interfered with by tall structures, and do not pass through building interiors well AGPS uses distance to cellular towers to approximate location when GPS signals are not obtainable.
When satellite signals are not obtainable, or accuracy is less important than life of the battery, applying Cell-ID is a useful substitute to GPS cell phone location. The location of the handset might be determined by the cellular network cell id, which identifies the cell tower the cell phone is connected to. By understanding the position of this tower, then you can know roughly the location where the handset will be. Still, a tower can cover a huge area, from a few hundred meters, in higher populationdensity areas, to several kilometers in lower density regions. For this reason location CellID precision is less than than GPS accuracy. Having said that location from CellID still provides a really handy alternative.
Another method of calculating mobile phone location is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation utilizes signal analysis data to calculate the time it takes signals traveling from your smartphone to at least 3 cell towers to calculate location.
Details about Cell Phone Apps for GPS Monitoring
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