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:
Apr. 20, 2010
Filed:
Jan. 11, 2007
Masashi Kisaka, Kanagawa, JP;
Masashi Kisaka, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
An infinite impulse response (IIR) filter circuit in accordance with an embodiment of the invention has transfer function coefficients that are adaptively changed. Using a Nth-order polynomial A(z) and a polynomial B(z) whose order is not higher than N, the transfer function is defined by is also defined. The polynomial A(z) is transformed to make the term of the Nth power of z equal to 1. If the order of the polynomial A(z) is even, the polynomial A(z) is determined to satisfy the condition: If the order N is odd, the polynomial A(z) is determined to satisfy the condition: where l and k(i=0, 1, 2,,,) are real numbers.