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. 08, 2008
Filed:
Jan. 19, 2007
Naotake Kitahira, Osaka, JP;
Naotake Kitahira, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The present invention is an multi stage noise shaping quantizer which includes: a first noise shaping quantizer that includes a first local quantizer which quantizes an input signal and a limiter which limits an output range of the first local quantizer, the first noise shaping quantizer performs noise shaping operation to the input signal; a second noise shaping quantizer that can input a first quantization error which occurs due to quantization operation at the first local quantizer and a limit error which occurs due to a limitation operation to the output range at the limiter as an input and performs noise shaping operation to the input; a differentiator that differentiates an output of the second noise shaping quantizer corresponding to a noise shaping order of the first noise shaping quantizer; an adder that adds an output of the differentiator to an output of the first noise shaping quantizer and output the resultant of the addition; and an amplitude controller that limits an amplitude of the limit error which occurs due to an operation of the limiter according to an output of the first local quantizer and an feedback output of the second noise shaping quantizer.