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, 1995
Filed:
Aug. 19, 1993
Fujitsu Limited, Kawasaki, JP;
Abstract
An automatic gain control circuit which is provided in a demodulation section of a modem to adjust the loop gain so that the level of a band-limited receive signal may have a predetermined reference value and to output the receive signal to an automatic equalization section of the modem. The automatic gain control circuit is improved in that, even when a disturbance of the circuit such as a gain hit or a drop-out occurs, regular communication can be continued without requiring a data mode leading-in operation. The automatic gain control circuit includes a reference value setting unit for generating a reference value, an error calculation unit for determining an error signal between the receive signal and the reference value, a receive level variation correcting controlling force setting unit for setting a receive level variation correcting controlling force to be added to the error signal, an error signal correction unit for correcting the error signal, an error signal averaging unit for averaging the corrected error signal and a feedback unit for feeding back, as the receive signal, the averaged corrected error signal. The receive level variation correcting controlling force to be set by the receive level variation correcting controlling force setting unit is varied in response to the error signal.