Mobile phone can be tracked after the closure of the GPS?
Similarly, if the phone opens the Wi-Fi Internet access, and the location of the latitude and longitude of Wi-Fi hotspots known, you can also calculate the location of the phone. When we turn off the GPS, or in the room (GPS does not work) can still use some mobile phone map software positioning, is the principle. However, due to technical differences, the accuracy of the positioning of the base station and Wi-Fi are worse than GPS.To achieve the tracking of the phone, you must have a mobile phone with. In other words, the mobile phone to the positioning of latitude and longitude information transmitted through the wireless network to the tracker. As long as the phone is not connected to the network (base station or Wi-Fi), even if the open GPS can not be traced. On the other hand, if the phone is only closed GPS services, and continue to communicate with the network (base station or Wi-Fi) to maintain the connection state, can still be traced to.
General principle: mobile phone base station positioning is switched on when the mobile phone search different communication base station signal near the location, to get different mobile phone communication base station TOA (Time of Arrival, at the time) or TDOA (Time Difference of Arrivalm, the time difference of arrival), according to the measurement results and combined with the base of latitude and longitude coordinates generally use the triangle algorithm, we can calculate the location of mobile phone. The actual location estimation algorithm needs to consider the multi base station (3 or more than 3) positioning, so the algorithm is much more complicated. In general, the number of mobile phone search to the base station, the higher the measurement accuracy, the higher the positioning performance.
When you open the phone GPS service, and through the wireless network to locate the GPS positioning information, the phone can be traced. If the phone closes the GPS service, can it be traced? The answer is yes, but some conditions are needed.GPS mobile phone is only one of the positioning function of the technology, but also through the communication base station, Wi-Fi hotspots and other mobile positioning. At present, the positioning technology used in all kinds of mobile phone positioning software is GPS positioning technology and base station positioning.
Can. Jia trillion mobile phone signal monitoring technology can detect.GPS is the English Global System (Global Positioning System), referred to as Positioning, is currently the most widely used positioning, navigation systems. GPS started in 1958, a project of the U.S. military, put into use in 1964, by the year, the global coverage of up to 98% of the 24 GPS satellite constellation has been completed. Now almost all of the intelligent mobile phone equipped with a GPS service, as long as the open GPS, we can use mobile phone navigation, shooting photos with location information, you can also use some cool and we are related to the position of mobile phone application. In addition, GPS can also help monitor the operation of the vehicle route, the location of the field staff, etc..
