Different GPS start techniques influence how much time is normally needed to deliver location.
GPS Hot Start refers to when the GPS enabled device keeps its last identified position, the satellites that were in view at the time, as well as the almanac information in memory, and tries to find the same satellites and determine a fresh position based upon the previous data. This is almost always the quickest GPS lock but Hot Start only works if the phone is in the same general area as when the GPS was last switched off.
GPS Warm Start refers to when the GPS enabled cell phone remembers its last calculated position, and almanac used, but not which satellites were in view. It resets and tries to obtain satellite signals and computes a new position. The GPS receiver narrows the choice of which satellites toseek because it stored its last known position and the almanac data helps identify which satellites are in range. The Warm Start is going to take longer compared to Hot Start but not as much as a Cold Start.
With GPS Cold Start, the device dumps all the previous data, and tries to locate satellites and achieve a GPS lock. This takes more time because there is no known reference information. The GPS enabled handset receiver has to attempt to lock onto a satellite transmission from any available satellites.
In order to have better GPS lock times (the timeframe it needs in order to lock onto an orbiting GPS Satellite signal) cellular phone manufacturers and network operators designed Assisted GPS technology. This downloads the ephemeris helping triangulate the device general location. GPS Receivers can get a faster lock at the expense of a few kilobytes of data transmission.
Assisted GPS, generally known as A-GPS or AGPS, boosts the performance of normal GPS in devices connected to the cell network. In America Sprint, Nextel, Verizon Wireless, and Alltel all use AGPS. Which is a means of using the cellular network to speed up finding of GPS satellites. A-GPS improves location tracking performance of smartphones (and also other connected devices) in a couple of ways:
The first way will be helping to obtain a faster “time to first fix” (TTFF). A-GPS receives and archives data about the location of satellites via the cell network and so the coordinates details does not need to be downloaded from the the satellite.
The second process is by assisting position smartphones when GPS signals are weak or not available. Since GPS satellite signals may be impeded by tall structures, and do not pass through building interiors well Assisted GPS makes use of proximity to cellular towers to estimate location when GPS signals are not accessible.
To be able to track a cellular consists of a number of principal ways of establishing cell phone location. GPS (Global Positioning System/Satellites), Triangulation, and CellID. These technologies transform cell phones into mobile tracking systems. These systems can be thought of as Network Based, Handset Based or a Hybrid technique. GPS position is Handset based mainly because it involves programs placed on the mobile phone combined with GPS hardware. Triangulation and CellID are Network Based simply because they make use of the equipment and information from the wireless provider. Hybrid systems bring together techniques to produce best use of available data and to help make perform faster.