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:
Mar. 30, 2004
Filed:
Apr. 02, 2001
Yuji Yamamoto, Saitama, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
An FM stereo signal demodulating apparatus includes a bandpass filter for extracting a 19 Hz signal from an FM detected signal; a first phase shifter for phase-shifting the 19 Hz signal by 90 degree; a first XOR for taking an exclusive OR between an output from the first phase-shifter and the 19 KHz signal; a second phase shifter for phase-shifting an output signal from said XOR ; a second XOR for taking an exclusive OR between an output from the first XOR and an output from the second phase shifter; an inverter for inverting an output from said XOR ; a third phase-shifter for phase-shifting an output signal from said inverter ; a third XOR for taking an exclusive OR between an output from said third phase-shifter and an output from said first XOR ; a first multiplier for multiplying an output from said first XOR and said FM detected signal; a second multiplier for multiplying an output from said third XOR and said FM detected signal; a third multiplier for multiplying an output from said second multiplier by {square root over (2)}−1; a first adder for adding an output from said first multiplier and an output from said third multiplier ; a second adder for adding said FM detected signal and an output from said first adder ; and a subtracter for subtracting an output from said first adder from said FM detected signal. In this configuration, the FM stereo demodulating apparatus can operate as a low speed.