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:
Oct. 08, 1985
Filed:
Jan. 27, 1983
Ronald H Tegethoff, Tinton Falls, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
An echo suppressor (21, 22) monitors signal levels associated with the working environment of an echo canceler (16, 17) to prevent spurious transient responses from the canceler. These spurious responses typically occur before the echo canceler has had sufficient time to appropriately adapt which is also the time when a call is first established. At such times, signaling and maintenance testing are performed in a telecommunications network and the echo canceler tends to produce an output when there is no actual transmit input signal. The echo suppressor includes a comparator (26, 27) which detects the presence of this output and the absence of an actual transmit input signal and operates a switch. The switch prevents the transient echo from propagating on the transmit path.