Patent ID: 8594698
Filing Date: 2013-11-26
Classification: G01S,H04W

Abstract:
1. A location-determining method, operable by a first portable RF communications device, the method comprising: (a) the first portable RF communications device monitoring its location by (i) receiving communications signals from a first plurality of fixed-location service-area antenna stations capable of RF communication with the first portable RF communications device wherein the antenna stations are substantially continuously operating, (ii) identifying at least one ID within at least one of the received communications signals, and (iii) measuring a varying signal characteristic other than ID, which signal characteristic is associated with a received communications signal from each of the first plurality of antenna stations; and (b) the first portable RF communications device determining if a first monitored location, monitored in accordance with part (a), is within proximity of a location chosen by a user of the first portable RF communications device, as a result of electronically comparing (i) the at least one ID at the first monitored location with at least one ID at the location chosen by the user and (ii) at least one number based on the varying signal characteristic of the communications signals from each of the first plurality of antenna stations at the first monitored location with at least one number based on corresponding varying signal characteristics of the communications signals from each of the first plurality of antenna stations at the location chosen by the user.