Calculating the location of a mobile device from signals sent by the device to base stations

personal area network (pan)
terminal-based positioning
pervasive computing
network-based positioning

The correct answer is: network-based positioning.

Network-based positioning is a method of determining the location of a mobile device by using signals sent by the device to base stations. The signals are received by the base stations and then processed by a central location system to determine the device’s location.

Personal area network (PAN) is a network of devices that are located close to each other, such as computers, phones, and printers. PANs are typically used to share data and resources between devices.

Terminal-based positioning is a method of determining the location of a mobile device by using sensors on the device. The sensors can be used to determine the device’s location based on its position relative to other objects, such as walls or landmarks.

Pervasive computing is a term used to describe the use of computers in everyday life. Pervasive computing devices are typically small and portable, and they are often used to connect to the internet or to other devices.

Network-based positioning is the most accurate method of determining the location of a mobile device. It is also the most widely used method. PANs, terminal-based positioning, and pervasive computing are all less accurate methods of determining the location of a mobile device.