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:
Oct. 05, 1999
Filed:
Apr. 07, 1997
Hiroshi Okawa, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A data transmission apparatus applicable to transmission of data by the use of a cable of a television camera system or the like and capable of ensuring simplified exact demodulation of data transmitted through quadrature modulation. The apparatus comprises a demodulator for outputting detection signals of the quadrature-modulated signal based on reference signals whose phases are each different by a predetermined value from an I-axis reference signal and a Q-axis reference signal in the quadrature modulation; a signal level corrector for correcting the signal levels of the detection signals; and a signal converter for converting the output signals of the signal level corrector to detection signals based on the I-axis and Q-axis reference signals. An equalizer circuit is further included in the apparatus for adaptively equalizing the output signals of the signal converter or the output signals of the signal level corrector. The quadrature-modulated signal is inputted via a coaxial cable, and the above predetermined value of the phase difference is an angle of 45 degrees.