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:
Jan. 18, 1977
Filed:
Jan. 22, 1976
Kotaro Kato, Tokyo, JA;
Haruki Takai, Tokyo, JA;
Nippon Electric Company, Ltd., Tokyo, JA;
Abstract
A clock signal reproducing network for PCM signal reception is capable of reproducing a clock signal even if the clock component is absent in the input digital signal for a prolonged period of time. The network includes a clock signal component extracting circuit and a bandpass filter for extracting and band-limiting the clock signal component in a received digital signal. An envelope detection circuit and a level decision circuit are connected to receive the output of the bandpass filter to provide a control signal to an output switching circuit. When the amplitude of the envelope of the filter output is high, the output of the bandpass filter is used directly as a reproduced clock signal. When the amplitude of the envelope is low, the clock signal obtained immediately before the filter amplitude becomes small is derived repeatedly from a delay circuit as a substituted clock signal.