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:
Feb. 12, 1991
Filed:
Sep. 29, 1989
Shigeo Shinada, Yokohama, JP;
Hiroyuki Fujita, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A monitor system for a multiplex equipment, comprising a multiplexing unit for multiplexing low speed group input signals of plural channels into a high speed group output signal and a demultiplexing unit for demultiplexing a high speed group input signal into low speed group output signals of plural channels, wherein the high speed group output signal and the low speed group input signals on one hand and the high speed group input signal and the low speed group output signals on the other hand are monitored through comparison on the basis of the low speed group signal. When discrepancy is detected in the comparison between the high speed group output signal and the low speed group input signal in a certain channel of the low speed group signal in the course of monitoring the multiplex unit, the comparison between the high speed input signal and the low speed output signal is performed in a different channel of the low speed group signal for monitoring the demultiplex unit. The time taken for making decision of the presence of fault from the detection of discrepancy in the comparison can be reduced, whereby exchange of the equipment suffering from the fault can be accomplished rapidly in response to the fault information, decreasing the shutdown duration involved in restoration.