Patent ID: 7013150

Claim:
A positioning system having: a positioning server for estimating a location of a mobile terminal in a service area comprised of a plurality of preset areas; and a plurality of base stations connectable to said terminal via radio links and connected to said positioning server via a network, wherein: each of said base stations has receiving means for receiving a signal transmitted from said terminal, measuring means for measuring a radio wave propagation environment between said terminal and the base station from the signal received by said receiving means, and means for sending the measurement result of said measuring means to said positioning server; said positioning server has storing means for storing a estimation result of the radio wave propagation environment between each of said preset areas and each of said base stations, and estimating means for estimating the location of said terminal by checking said estimation results stored in said storing means against said measurement results from said base stations; and said positioning server further has estimating means for estimating the radio wave propagation environment between each of said preset areas and each of said base stations based on at least the location of each of said base stations and placement of structures in said service area.