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:
Dec. 11, 2001
Filed:
Aug. 06, 1998
Cell-Loc Inc., Calgary, CA;
Abstract
The intention of the invention is to produce a network-based Wireless Location System (WLS) whereby existing Advanced Mobile Phone System (AMPS) Frequency Division Multiple Access (FDMA) Cellular Telephones (CTs) can be located passively without modification to the CTs or to the cellular antenna infrastructure. More specifically, the invention consists of methods and apparatus to estimate the position and velocity of a Cellular Telephone (CT) using either the Time Of Arrival (TOA) of a signal transmitted by the CT, its Phase Of Arrival (POA), its Frequency Of Arrival (FOA), or a combination thereof, at several antennas at a number of Monitoring Sites (MSs). In order to solve for the coordinates of the CT, the patent uses either hyperbolic multilateration based on Time Difference Of Arrival (TDOA), or linear multiangulation based on Phase Difference Of Arrival (PDOA), or both. In order to solve for the velocity of the CT, the patent uses FOA based on Frequency Difference Of Arrival (FDOA). An important contribution of this invention is the way the CT is forced to transmit radio signals for location purposes. Another important contribution is the application of Super-Resolution (SR) techniques to increase the resolution of the estimated TOAs, POAs or FOAs.