Automatic vehicle location in cellular communications systems

The paper presents a method of automatic vehicle location (AVL). Signals are transmitted from base stations in a cellular communications system. A device is embedded into a cellular phone installed in a vehicle. When this vehicle is traveling through a cellular territory, the device receives those signals and calculates the attenuation of those signals to locate the current vehicle position. A preliminary study by using computer simulation shows that the error between the exact position and the estimated position is in the range from 0 to 575 m. This result is based on the assumptions that the base stations are separated from each other by 5 km and the point-to-area terrain configuration has a 3 dB standard deviation of a normal signal strength distribution. A further modification by employing fuzzy logic is under development. The goal is to keep the location accuracy within 200 m