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:
Nov. 09, 2000
David G. Worthy, Gilbert, AZ (US);
Other;
Abstract
An interference attenuating remote audience survey system ( ) is configured to identify radio stations ( ) to which tuners ( ) are tuned, the tuners ( ) having local oscillator (LO) signals ( ) emitted therefrom. The system ( ) includes a first antenna ( ) for sensing a first signal ( ) at a selected LO frequency ( ), the first signal ( ) including one of the LO signals ( ) and an interference signal ( ). A second antenna ( ) receives a second signal ( ) at the selected LO frequency ( ), the second signal ( ) including an interference signal ( ). A shield element ( ) shields the second antenna ( ) from receiving the one of the LO signals ( ). The first and second signals ( ) are subtractively combined to produce a third signal ( ), the interference signal ( ) being attenuated from the third signal ( ). A receiver ( ) is configured to detect the one of the LO signals ( ) within the third signal ( ) to determine that one of the tuners ( ) is tuned to the one of the radio stations ( ) associated with the detected LO signal ( ).