Method and system for positioning mobile units based on angle measurements

Abstract

A method and system for positioning mobile units using angle measurements taken by neighboring mobile units is disclosed. A selected mobile unit and mobile units in the vicinity of the selected mobile unit are selectively instructed to measure and report information related to the position of the selected mobile unit. The reported information is used to compute a position of the selected mobile unit.

What is claimed is: 
     
         1 . A method of determining a degree of confidence in a computed position, the method comprising:
 receiving a plurality of reported angle measurements for a particular target mobile unit;   compounding the reported angle measurements;   computing a position of the particular target mobile unit; and   calculating the degree of confidence in the computed position by calculating a number of properly reported angle measurements.   
     
     
         2 . The method of  claim 1  wherein the higher the number of properly reported angle measurements, the higher the degree of confidence. 
     
     
         3 . The method of  claim 1  further comprising:
 setting a required amount of reported angle measurements. 
 
     
     
         4 . The method of  claim 3  further comprising:
 setting a required level of confidence. 
 
     
     
         5 . The method of  claim 1  further comprising:
 receiving a reported angle measurement between the particular target mobile unit and a base station. 
 
     
     
         6 . The method of  claim 1  further comprising:
 receiving a signal indicating a properly measured direction of arrival from the particular target mobile unit and a base station. 
 
     
     
         7 . The method of  claim 1  further comprising:
 receiving a signal indicating that it was not possible to properly measure one or more directions of arrival from the particular target mobile unit and a base station. 
 
     
     
         8 . A base station configured to perform the method of  claim 1 . 
     
     
         9 . A radio network controller configured to perform the method of  claim 1 . 
     
     
         10 . A radio network controller comprising:
 circuitry configured to receive a plurality of reported angle measurements for a particular target mobile unit;   circuitry configured to compound the reported angle measurements;   circuitry configured to compute a position of the particular target mobile unit; and   circuitry configured to calculate the degree of confidence in the computed position by calculating a number of properly reported angle measurements.   
     
     
         11 . The radio network controller of  claim 10  wherein the higher the number of properly reported angle measurements, the higher the degree of confidence. 
     
     
         12 . The radio network controller of  claim 10  further comprising:
 circuitry configured to set a required amount of reported angle measurements. 
 
     
     
         13 . The radio network controller of  claim 10  further comprising:
 circuitry configured to set a required level of confidence. 
 
     
     
         14 . The radio network controller of  claim 10  further comprising:
 circuitry configured to receive a reported angle measurement between the particular target mobile unit and a base station. 
 
     
     
         15 . The radio network controller of  claim 10  further comprising:
 circuitry configured to receive a signal indicating a properly measured direction of arrival from the particular target mobile unit and a base station. 
 
     
     
         16 . The radio network controller of  claim 10  further comprising:
 circuitry configured to receive a signal indicating that it was not possible to properly measure one or more directions of arrival from the particular target mobile unit and a base station. 
 
     
     
         17 . A base station comprising:
 circuitry configured to receive a plurality of reported angle measurements for a particular target mobile unit;   circuitry configured to compound the reported angle measurements;   circuitry configured to compute a position of the particular target mobile unit; and   circuitry configured to calculate the degree of confidence in the computed position by calculating a number of properly reported angle measurements.   
     
     
         18 . The base station of  claim 17  wherein the higher the number of properly reported angle measurements, the higher the degree of confidence. 
     
     
         19 . The base station of  claim 17  further comprising:
 circuitry configured to set a required amount of reported angle measurements. 
 
     
     
         20 . The base station of  claim 17  further comprising:
 circuitry configured to set a required level of confidence.