Method for determining position by obtaining directional information from spatial division multiple access (SDMA)-equipped and non-SDMA-equipped base stations

For use in a wireless communication system including a plurality of Spatial Division Multiple Access (SDMA)-equipped base stations each having a smart antenna with a predetermined number of floating lobes, each of the lobes operative to track and communicate with a mobile unit on a corresponding communication channel by changing its orientation within a predetermined direction range, a method for determining the position of a mobile unit, comprising:

• for each of the base stations, determining in cooperation with a receiver, a plurality of RF measurements for the base station, for a predetermined plurality of distances and directions;
• for each of the base stations, modeling its determined RF measurements as a scaled contour shape having minimum and maximum boundaries;
• determining where the contour shapes of the neighboring base stations intersect so as to define a first bounding polygon area that describes the relative position of the mobile unit;
• determining which lobes of the neighboring base stations are in communication with the mobile unit;
• determining the orientation ranges of the communicating lobes of the neighboring base stations in terms of azimuth angles so as to define a second bounding polygon area that describes the relative position of the mobile unit;
• and
• determining where the first and second bounding polygon areas intersect so as to define a location polygon that describes the position of the mobile unit in terms of minimum and maximum error estimate.

For use in a wireless communication system including a plurality of Spatial Division Multiple Access (SDMA)-equipped and non-SDMA-equipped base stations each having an antenna with a corresponding coverage area, a method for determining the position of a mobile unit, comprising:

• for each of the non-SDMA-equipped base stations, providing a plurality of bandpass filters in electrical communication with the corresponding antenna, each of the band-pass filters having a corresponding waveguide and operative to receive mobile unit signals from predetermined directions in predetermined frequency slots;
• for each of the base stations, determining in cooperation with a receiver, a plurality of RF measurements for the base station, for a predetermined plurality of distances and directions;
• for each of the base stations, modeling its determined RF measurements as a scaled contour shape having minimum and maximum boundaries;
• determining where the contour shapes of the neighboring base stations intersect so as to define a first bounding polygon area that describes the relative position of the mobile unit;
• determining the communication frequencies of the neighboring base stations and the corresponding directions of their received mobile unit signals so as to define a second bounding polygon area that describes the relative position of the mobile unit;
• and
• determining where the first and second bounding polygon areas intersect so as to define a location polygon that describes the position of the mobile unit in terms of minimum and maximum error estimate.