Position determination systems and methods utilizing error of multiple candidate positions

Abstract

Examples of systems and methods described herein may be used to track a tagged object through a scene. Techniques are described herein to calculate a position of the tag using wireless communication with multiple anchor devices. In some examples, the anchor devices may be self-localizing, e.g., they may dynamically determine their position and relationship to one another. In some examples, position of a tag may be calculated by calculating multiple candidate positions using different localization techniques—such as geometric localization techniques and/or optimization-based techniques. An error may also be identified associated with each candidate position. A final position may be determined for the tag based on the errors associated with the candidate positions (e.g., the candidate position with the smallest error may be utilized as the position, e.g., the determined position, of the tag).

What is claimed is: 
     
         1 . A system comprising:
 a plurality of anchor devices, each comprising:
 a transceiver; 
 an inertial measurement unit configured to monitor movement of the anchor device; 
 a processor coupled to the transceiver and configured to self-localize a respective anchor device to determine a position of the respective anchor devices, the processor further coupled to the inertial measurement unit and configured to determine a position of the anchor device when it is stationary; and 
   a tag comprising:
 a tag transceiver configured to communicate with the plurality of anchor devices; and 
 a tag processor coupled to the tag transceiver and configured to determine a position of the tag using the respective positions of the plurality of anchor devices, the tag processor configured to calculate multiple candidate positions using geometric localization techniques, optimization techniques, smoothing techniques, or combinations thereof and errors associated with each of the multiple candidate positions; the tag processor further configured to select the position of the tag based on the errors associated with each of the multiple candidate positions, 
   
     
     
         2 . The system of  claim 1 , further comprising:
 a display device in communication with the tag and configured to display an indication of the tag in accordance with the position.   
     
     
         3 . The system of  claim 2 , wherein the display device is configured to display the position of the tag together with a floorplan of a building in which the tag is deployed. 
     
     
         4 . The system of  claim 1 , wherein the plurality of anchor devices are each configured to self-localize responsive to a determination that a respective anchor device is stationary. 
     
     
         5 . The system of  claim 1 , wherein the tag processor is configured to determine a first candidate position of the tag using a geometric localization technique and a second candidate position of the tag using an optimization technique.