Position measurement using Bluetooth

A Bluetooth wireless indoor position-measurement system is described. Normal Bluetooth operation uses receiver signal strength indicator (RSSI) for automatic transmitter power control to ensure satisfactory received signal-to-noise ratio. This feedback system was disabled and a novel use of RSSI allowed a series of measurements to be made. The distance was estimated between a reference transmitter and a mobile receiver, using a line-of-sight radio propagation model within a single cell. The design, implementation and evaluation of the system demonstrated that a mean absolute range error of 1.2 m was feasible in the presence of multipath fading.