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:
Nov. 09, 1982
Filed:
Dec. 12, 1980
Giancarlo Pirani, Turin, IT;
Abstract
An analog signal sent from one telephone subscriber to another is differentiated at a transmitting terminal and the resulting derivative is distorted by mixing with a random or pseudorandom sequence of bipolar binary pulses before being conveyed, e.g. by frequency modulation, to a receiving terminal where it is mixed with a like pulse sequence to re-establish the undistorted derivative signal with substantial suppression of interferences from other users of the same signal link. The re-established signal is integrated over intervals equal to a basic pulse period of the binary sequence and each signal sample thus obtained is additively combined with the sample from the immediately preceding period to restore the original analog signal. The signal link utilized may be an emergency channel made available, e.g. for communication with a mobile station, when regular channels are busy.