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. 03, 1995
Filed:
Mar. 03, 1994
Yasunori Kawakami, Osaka, JP;
Akira Iketani, Higashiosaka, JP;
Kei Ichikawa, Osaka, JP;
Makoto Goto, Nishinomiya, JP;
Haruo Isaka, Yawata, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A pilot signal is superposed and recorded on data at the beginning of each track. The beginning portion of the track is constituted only of codewords having a disparity of each 10 bits which is +2, 0 or -2. Also, the cumulative value of the disparities of every 10 bits may fluctuate in a period coinciding with the period of the pilot signal to be superposed. Therefore, the frequency spectrum in the beginning part of the track has a peak at the frequency of pilot signal, and using this peak as the pilot signal, tracking is controlled during reproduction.