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. 08, 2000
Filed:
Feb. 22, 1996
Toshihiko Fukuoka, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
There is provided an EFM encoder comprising a DSV calculator which is smaller in circuit scale than a conventional DSV calculator. The above DSV calculator has a merging-bit DSV calculator, a frame-signal DSV/polarity evaluator, adding means, and an overflow/underflow processor. The merging-bit DSV calculator calculates merging-bit DSV data based on merging bits and on a cumulative polarity signal. The frame-signal DSV/polarity evaluator outputs frame-signal DSV data in consideration of the polarity in the final bit of the merging bits. The adding means adds up the cumulative DSV data, the merging-bit DSV data, and the frame-signal DSV data so as to calculate DSV. The overflow/underflow processor performs, when overflow or underflow has occurred in the result of calculation from the adding means, exception handling with respect to the calculation result and outputs the calculation result that has undergone the exception handling as new cumulative DSV data. Even when overflow or underflow has occurred in the obtained cumulative DSV data, the accuracy of DSV calculation performed by the DSV calculator is not reduced.