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:
Sep. 05, 1978
Filed:
Feb. 01, 1977
Takashi Kurokawa, Kodaira, JP;
Michio Fujiwara, Kodaira, JP;
Yoshio Akutsu, Koganei, JP;
Akoi Otani, Owariasahi, JP;
Harumi Nagasawa, Hadano, JP;
Masujiro Matsuo, Yokohama, JP;
Yasuo Ishii, Tokyo, JP;
Sigeru Ogawa, Musahino, JP;
Schun'ichi Itoh, Musashino, JP;
Daisuke Takei, Musashino, JP;
Hitachi Denshi Kabushiki Kaisha, ALL OF, JP;
Japanese National Railways, ALL OF, JP;
Hitachi, Ltd., ALL OF, JP;
Abstract
An ac type line concentrator for use in a data communication system, comprising a crosspoint switch circuit. The crosspoint switch circuit is constituted by a plurality of crosspoint switches capable of switching an analog signal (hereinafter referred to as an analog switch), so that a carrier signal modulated by a data signal may be transferred from one of m incoming lines connected with m terminal units to a selected one of n(n<m) outgoing lines connected with a central unit through the ac type line concentrator without being demodulated.