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. 23, 1999
Filed:
Jan. 15, 1998
Noboru Nakagawa, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A headphone apparatus includes a plurality of antennas for receiving an FM signal produced by FM-modulating a carrier signal with an audio signal, a plurality of tuning circuits for receiving reception signals of the plurality of antennas, a mixer circuit for causing tuning coils of the tuning circuits to be transformer-coupled to each other and for frequency-converting an output signal of one tuning circuit into an intermediate frequency signal, an FM demodulating circuit for FM-demodulating the intermediate frequency signal to produce the audio signal, and an acoustic unit for converting this audio signal into a sound. The directivity axes of the antennas are arranged perpendicularly thereby improving the reception of this headphone apparatus.