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:
Jul. 24, 2007
Filed:
Aug. 22, 2005
Alexander E. Smith, McLean, VA (US);
Bennett Cohen, Alexandria, VA (US);
Alexander E. Smith, McLean, VA (US);
Bennett Cohen, Alexandria, VA (US);
ERA Systems Corporation, Alexandria, VA (US);
Abstract
A method of triangulating aircraft transponder signals using a number of receivers connected to a central station over communication links includes applying at least one logic rule at each receiver to incoming transponder signals to filter redundant transponder signals, time-stamping filtered transponder signals, and transmitting time-stamped transponder signals to the central station. Logic rules include at least one of altitude filtering, Mode S, Mode A/C code filtering, and change filtering. Replies are accepted when a change in state is indicated, such that the only those replies indicating a change in state are time-stamped and sent to the central server.