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:
Jun. 23, 1992
Filed:
Mar. 28, 1989
Masafumi Shimotashiro, Osaka, JP;
Toyohiko Matsuta, Osaka, JP;
Masaaki Kobayashi, Kawanishi, JP;
Etsuto Nakatsu, Osaka, JP;
Hiroaki Shimazaki, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A digital signal magnetic recording and playback apparatus which is applicable to digital video signals, utilizes quadrature amplitude modulation to produce a recording signal from a digital input signal with a carrier frequency being employed which is less than or equal to than the frequency of a recording system clock signal that is synchronized with the successive data values of the digital input signal. Carrier bursts are periodically inserted into the recording signal with a fixed period, through data inserted by a burst data insertion circuit and the carrier and clock signal are arranged to periodically coincide in phase, with the aforementioned period. The carrier frequency is made equal to the clock frequency multiplied by a factor (n/m), where n and m are integers and n<m. During playback, time information obtained from the bursts is used to mutually phase-relate recovered clock and carrier signals.