The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 11, 2000
Filed:
Apr. 17, 1998
James Edward Mitzlaff, Arlington Heights, IL (US);
John Duncan Toone, Cary, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
Error vectors are added to any position estimate determined by Location finding equipment (LFE) in order to give a corrected position estimate. Error vectors are determined utilizing calibration terminals (114), which are roaming vehicles that move throughout the communication system's (100) coverage area. Each calibration terminal (114) comprises a remote unit (113) coupled with an independent position determining system (167) such as a Global Positioning System (GPS) receiver. Error vectors are determined by periodically polling calibration terminals (114). In response, each terminal (114) sends back a reply message containing their actual, independently determined location, along with periodically broadcasting a known sequence at increased power utilized by the LFE in determining a position estimate of the calibration terminal (114). The difference between the actual, and LFE determined position estimates are utilized in calculation of error vectors.