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:
Feb. 11, 1997
Filed:
Jun. 26, 1995
Applicant:
Inventor:
Yasuyuki Chaki, Chiba, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
359181 ; 359183 ; 375281 ; 375298 ; 375308 ; 371 30 ;
Abstract
A digital signal transmitting apparatus, a digital signal transmitting method, and a digital signal transmitter-receiver, for transmitting a digital signal within a specified frequency band by using an infrared transmission method. An infrared signal within a specified frequency band can be obtained by using a QPSK modulation circuit 13 having roll-off filters 132 and 133 and applying roll-off filtering and QPSK modulation to an inputted digital audio signal, and thereby generating a digital modulated signal S2 whose bandwidth is narrowed and driving an infrared emitter based on the modulated digital audio signal S2.