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:
Nov. 22, 1983
Filed:
Mar. 17, 1981
Kiyoyuki Sugihara, Tokorozawa, JP;
Shibasoku Company Limited, Tokyo, JP;
Abstract
An apparatus for measuring a distortion factor of an analog input signal comprises a frequency multiplier for producing a sampling signal having a frequency of the input signal multiplied by N, an analog to digital converter for successively converting instantaneous values of the input signal into digital values, a memory circuit for storing the converted digital values at given address positions in the memory circuit, a digital to analog converter for reading out the digital values stored in the memory circuit in a correct phase sequence at a given reading-out frequency and converting read-out digital values into analog values, a filter tuned to a frequency equal to the reading-out frequency divided by N and filtering out a fundamental component of the input signal, and a level meter for measuring a level of an output signal supplied from the filter. The distortion factor is calculated from a measured level of the output signal from the filter and a level of the fundamental component.