Patent ID: 6122512
Filing Date: 2000-09-19
Classification: G01S,H04W

Abstract:
A method of determining the position of a mobile station in a TDMA-type mobile radio system, which includes at least one base station controller with associated radio base transceiver stations and at least one mobile radio switching center, wherein while connected to a given first base station the mobile station continuously evaluates the radio connections from a first plurality of base stations, and wherein said first plurality of base stations are placed in ranking order and inserted in a ranking list, the method comprising the steps of:a) designating a second plurality of base stations from said first plurality of base stations from said list;b) ordering the mobile station to handover to a designated second base station among said second plurality of base stations;c) initiating a handover from the mobile station to said designated second base station by sending an access signal to said designated second base station;d) in the same way as with handover, at said designated second base station,measuring and recording a first time delay upon the arrival of the access signal relative to the arrival time expected at said designated second base station if the mobile station were located in the same place as said designated second base station;e) inhibiting confirmation of the access signal received from the mobile station by said designated second base station;f) evaluating the recorded first time delay; andg) repeating the commands and measuring procedures according to steps b)-f) in at least one additional base station selected from said second plurality of base stations; andwherein after there is obtained at least one additional time delay, the recorded first time delay along with the at least one additional time delay can be used to calculate the position of the mobile station.