Patent ID: 6785536
Filing Date: 2004-08-31
Classification: H04M,H04W

Abstract:
A method for determining whether the subscriber of a mobile phone is located within a home zone service to qualify for a different charging rate, comprising the steps of:(a) measuring a round trip delay (RTD) from a plurality of testing locations within a sector of a cell site in relation to a plurality of neighboring base stations to determine a plurality of reduced charging areas with a mobile phone subscription, wherein the boundary of the reduced charging areas are defined by a first mean RTD value and a second mean RTD value; (b) preparing a predetermined home zone database by associating the plurality of the reduced charging areas with the mobile phone subscription using the first value and the second value; (c) calculating a round trip delay (RTD) if the mobile phone generates a request signal to establish a call connection; and, (d) determining whether the measured RTD falls within a range between the first value and the second value associated with the mobile phone in the home zone database to determine whether the mobile phone is located within the home zone service.