Local positioning system

A local positioning system implemented on a computer for determining the position of a mobile station, comprising:

• means for receiving pilot channel signal information indicating arrival times of pilot channel signals at the mobile station;
• means for estimating a distance from the mobile station to one of a plurality of base stations by minimizing a set of distance error cost functions including angles formed by the base stations and the mobile station;
• and
• means for estimating the location of the mobile station by minimizing a set of position error cost functions based on the pilot channel signal information and on base station information indicating the location of the plurality of base stations to which the arrival time information is associated.

An executable program embodied on a computer-readable medium for determining the position of a mobile station comprising:

• a receiving source code segment for receiving pilot channel signal information indicating arrival times of pilot channel signals at the mobile station;
• a computing source code segment for estimating a distance from the mobile station to one of a plurality of base stations by minimizing a set of distance error cost functions including angles formed by the base stations and the mobile station;
• and
• an estimating source code segment for estimating the location of the mobile station by minimizing a set of position error cost functions based on the pilot channel signal information and on base station information indicating the location of a the plurality of base stations to which the arrival time information is associated.

A computer data signal comprising:

• a receiving signal segment for receiving pilot channel signal information indicating arrival times of pilot channel signals at the mobile station;
• a computing signal segment for estimating a distance from the mobile station to one of a plurality of base stations by minimizing a set of distance error cost functions including angles formed by the base stations and the mobile station;
• and
• an estimating signal segment for estimating the location of the mobile station by minimizing a set of position error cost functions based on the pilot channel signal information and on base station information indicating the location of the plurality of base stations to which the arrival time information is associated.