Title:
DIGITAL FILTER
Document Type and Number:
Japanese Patent JPH01144716
Kind Code:
A
Abstract:
PURPOSE:To extract a specified frequency signal by gating an input signal with a gate circuit based on the output of an operating circuit because this arithmetic circuit, which operates the phase change of the input signal in a sampling cycle, outputs information concerning the frequency of the input signal. CONSTITUTION:The arithmetic circuit 7 to operate the phase change of the input signal in the sampling cycle, a comparator 8, which compares the output of the operating circuit 7 and a reference value, and a gate circuit 10 to be controlled by the output of the comparator 8 and to gate the input signal are provided. Namely, since the operator 7, which operates the phase change of the input signal in the sampling cycle, outputs the information concerning the frequency of the input signal, the input signal is gated by the gate circuit 10 based on the output of this operating circuit 7. Thus, without generating an unnecessary signal and generating an error due to operation, the specified frequency signal can be extracted.
Inventors:
ISHIZAKA KUNIMASA
Application Number:
JP30286387A
Publication Date:
June 07, 1989
Filing Date:
November 30, 1987
Export Citation:
Assignee:
NIPPON DENKI HOME ELECTRONICS
International Classes:
H03H17/08; (IPC1-7): H03H17/08
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