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. 25, 2003
Filed:
Oct. 31, 2000
Takafumi Terahara, Kawasaki, JP;
Takeshi Sakamoto, Kawasaki, JP;
Hiroaki Tomofuji, Kawasaki, JP;
Motoyoshi Sekiya, Kawasaki, JP;
Makoto Murakami, Sapporo, JP;
Kazuo Yamane, Kawasaki, JP;
Hiroshi Onaka, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
In a method of measuring an optical signal-to-noise ratio according to the present invention, a partial optical signal-to-noise ratio is defined, the partial optical signal-to-noise ratio is calculated from a predetermined physical quantity, the sum of inverse numbers of the partial optical signal-to-noise ratios is calculated, and further an inverse number of the sum is calculated to acquire an optical signal-to-noise ratio. The present invention makes it possible to measure optical SNR without directly measuring ASE in the optical signal. The present invention provides a measuring apparatus, a measuring circuit, a pre-emphasis method, an optical communication system, and a controlling apparatus each utilizing this method.