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:
Jun. 08, 2004
Filed:
Feb. 26, 2001
Takayuki Miyakawa, Kamifukuoka, JP;
Masatoshi Suzuki, Kamifukuoka, JP;
Noboru Edagawa, Kamifukuoka, JP;
Other;
Abstract
An optical fiber ( ) with a large effective core area and a large chromatic dispersion value is disposed on an input side of signal light, and an optical fiber ( ) with a small effective core area and a small chromatic dispersion value or a chromatic dispersion value of negative polarity is disposed on an output side of the signal light. A pumping light source ( ) generates pumping light of 1450 nm to cause Raman amplification of 1550 nm in the optical fiber ( ). The output light from the pumping light source ( ) enters the optical fiber ( ) from the back through a WDM optical coupler ( ). Provided that y=(Pin−&agr;)/(Pp·10 Log L) where input power of the optical fiber ( ) (i.e. output power of an optical transmitter ( )) is Pin, a total loss of the optical fibers ( and ) is &agr;, pumping power for Raman amplification is Pp, and a total length of the optical fibers ( and ) is L, the relation between ratio x (0≦x≦1) of the optical fiber ( ) and y is expressed as y=6.63×10 x−0.077. Here, the satisfactory x value is in a range from +0.2 to −0.2 of the y value.