Method and apparatus for geo-locating mobile station

A method for estimating a geographic location of a mobile station within a coverage area of a wireless network, comprising:

• calculating a radial distance of an individual mobile station from a first base station serving the individual mobile station, the first base station including multiple sector antennas, the radial distance based at least in part on a round trip measurement associated with elapsed time between sending an outgoing signal from the first base station to the individual mobile station and receiving a corresponding acknowledgement signal from the individual mobile station at the first base station;
• determining a signal strength report from the individual mobile station provided to the first base station related in calendar time to the round trip measurement includes a first signal strength measurement representative of a power characteristic of a first radio frequency (RF) signal received by the individual mobile station from a first sector antenna of the first base station, the signal strength report not including other signal strength measurements for other sector antennas of the first base station;
• and
• identifying an instant geographic location of the individual mobile station in a coverage area of a wireless network formed by at least the first base station, the instant geographic location based at least in part on an intersection of a circle having a center defined by the first base station and a radius defined by the radial distance with a first sub-sector geographic area in a first RF coverage map for the first sector antenna, the first RF coverage map including a first reference location for the first base station to facilitate correlation of the circle to the first RF coverage map, the first RF coverage map formed by a plurality of sub-sector geographic areas, the first RF coverage map populated with representative RF coverage levels associated with previous signal strength measurements for the first sector antenna from one or more mobile stations in previous signal strength reports comprising the corresponding previous signal strength measurement and at least one signal strength measurement from another sector antenna of the first base station, wherein the first sub-sector geographic area in the first RF coverage map is populated with a first RF coverage level representative of lacking previous signal strength measurements.

A method for estimating a geographic location of a mobile station within a coverage area of a wireless network, comprising:

• calculating an instant angular position of an individual mobile station in relation to a first base station, the first base station including multiple sector antennas, the instant angular position based at least in part on a first signal strength measurement, a second signal strength measurement, and an angular position reference that extends outward from the first base station, the first and second signal strength measurements related in calendar time and representative of power characteristics of respective radio frequency (RF) signals received by the individual mobile station from corresponding first and second sector antennas of the first base station;
• determining a radial distance of the individual mobile station from a second base station serving the individual mobile station, the second base station including multiple sector antennas, the radial distance based at least in part on a round trip measurement associated with elapsed time between sending an outgoing signal from the second base station to the individual mobile station and receiving a corresponding acknowledgement signal from the individual mobile station at the second base station, the round trip measurement related in calendar time to the first and second signal strength measurements;
• and
• identifying an instant geographic location of the individual mobile station in a coverage area of a wireless network formed by at least the first and second base stations, the instant geographic location based at least in part on an intersection of a line extending outward from the first base station at the instant angular position with a circle having a center defined by the second base station and a radius defined by the radial distance.