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:
Mar. 15, 2005
Filed:
Jun. 07, 2000
Shigefumi Masuda, Kawasaki, JP;
Hiroo Tamura, Kawasaki, JP;
Minoru Ishida, Kawasaki, JP;
Kazunari Inoue, Kamakura, JP;
Takayuki Tyou, Kamakura, JP;
Shigefumi Masuda, Kawasaki, JP;
Hiroo Tamura, Kawasaki, JP;
Minoru Ishida, Kawasaki, JP;
Kazunari Inoue, Kamakura, JP;
Takayuki Tyou, Kamakura, JP;
Fujitsu Limited, Kawasaki, JP;
Miharu Communications Co., Ltd., Kamakura, JP;
Abstract
The present invention concerns an ingress noise control system and an ingress noise blocking device which are used in a cable system to suppress ingress noise. In the cable system providing two-way communication using different frequency bands for transmission of upstream and downstream signals, the ingress noise control system includes, within a distribution unit, a two-way amplification unit, etc. provided in an upstream signal transmission path, a synchronous detection controllerfor synchronously detecting the upstream signal transmitted from terminal equipment and separated by a low-pass filterin a second separation filter, a gate switch circuitwhich is turned on by the synchronous detection controllerto pass the upstream signal only when the upstream signal is synchronously detected, and an indicatorfor indicating the on/off state of the gate switch circuit