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.

Date of Patent:
Apr. 23, 2002

Filed:

Jul. 17, 1998
Applicant:
Inventors:

Toshio Kawazawa, Tokyo, JP;

Koji Goto, Tokyo, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04J 1/402 ; H04J 1/400 ; H04J 1/408 ; H04B 1/016 ;
U.S. Cl.
CPC ...
H04J 1/402 ; H04J 1/400 ; H04J 1/408 ; H04B 1/016 ;
Abstract

In an optical transmission, system, a trunk cable having two pairs of optical fibers is provided between first and second trunk stations to use one of the two pairs of the optical fibers for communication between the first and second trunk stations and the other for communication with first and second branch stations. Two branching units of first and second, and third and forth, are respectively provided for the first and second branch stations, and connected to each of the associated first and second branch stations, by first and second or third and forth branching cables. The first branch station connects to the first branching unit via the first branching cable having two pairs of optical fibers, and connects to the second branching unit via the second branching cable having two pairs of optical fibers. One of the two pairs of the optical fibers of the first branching cable and one of the two pairs of the optical fibers of the second branching cable are normally used, and the others are reserved as spare fibers. Alternatively, the first branching cable is normally used, and the second branching cable is reserved as a spare cable.


Find Patent Forward Citations

Loading…