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:
Nov. 02, 2004
Filed:
Apr. 29, 2002
David L. Herrick, Mont Vernon, NH (US);
Bae Systems Information and Electronic Systems Integration Inc., Nashua, NH (US);
Abstract
A method and apparatus for minimizing multipath interference for commercial FM signals which use SCA secondary signals in QAM format that includes tracking the time series of phase measurements of a received stereo pilot signal for determining the proper phase reference for demodulation of QAM signals at the center of the time series. Phase measurements of the pilot signal are tracked over a predetermined tracking period. The phase measurement is used to support demodulation of the QAM signal. The SCA secondary signals in QAM format transmitted on commercial FM have minimal multipath interference and Doppler interference by movement of transmitter and receiver (vehicular).