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:
Jul. 01, 1997
Filed:
Nov. 14, 1995
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A signal for which the amplitude of envelope becomes substantially 0 only for a certain period of time within the time of a period T, and a measured signal having a certain amplitude are synthesized, and the synthesized signal is optically transmitted. When a plurality of reflection points are present on a light transmission line, there is an increase in harmonic distortion or intermodulation distortion as well as in cross modulation distortion after receiving. This increase in cross modulation distortion causes an increase in variation of amplitude of the measured signal. In such a case, it is possible to calculate the distance between, and/or reflectance of, reflection points present on end faces of optical elements and/or connecting points of optical fibers on the light transmission line by investigating first periodical characteristics of variation of the transmitted measured signal during transmission relative to the change in central light frequency of the signal light, or investigating second periodical characteristics of variation of the transmitted measured signal during transmission corresponding to the change in the frequency of the measured signal.