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:
Apr. 14, 1981
Filed:
Jan. 08, 1979
Applicant:
Inventors:
Alan A Schneider, Reisterstown, MD (US);
Govind R Gadwal, Reisterstown, MD (US);
Assignee:
Catalyst Research Corporation, Baltimore, MD (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04J / ; H04M / ;
U.S. Cl.
CPC ...
179 / ; 370 30 ; 370 69 ;
Abstract
A telephone system is provided which requires no central office. All the stations on the system are interconnected by a single line or cable and each station includes a computer which carries out the necessary switching. Each station is then able to call any other station, or to respond to a call, without requiring any central office. Frequency division multiplexing is used to permit a number of conversations to be carried on simultaneously and two frequencies are assigned to each conversation to permit duplex operation. A page capability is also provided.