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. 08, 1981
Filed:
Feb. 21, 1979
Applicant:
Inventor:
Baldev Krishan, San Jose, CA (US);
Assignee:
Anderson Jacobson, Inc., San Jose, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
179 / ;
Abstract
For the type of modem that transmits information by way of quadrature amplitude modulation (QAM) over a telephone line, an electronic circuit for compensating for amplitude distortion created by use of an acoustic coupler with an ordinary telephone handset. The circuit is positioned in the acoustic coupler between the modem and the coupler's microphone and receiver. This circuit compensates for amplitude distortion introduced by the acoustic coupling within the data transmission frequency bands of the modem.