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:
Jun. 29, 2004
Filed:
Nov. 24, 1998
Matthew Harper, Arlington Heights, IL (US);
Richard J. Dynarski, Glen Ellyn, IL (US);
Timothy G. Mortsolf, Lisle, IL (US);
Kenneth L. Peirce, Jr., Barrington, IL (US);
3Com Corporation, Santa Clara, CA (US);
Abstract
Tones that are generated by a telephone or PC (such as DTMF tones) and subject to loss or noise during generation or during transmission along a medium are detected and replaced with substantially noise-free and distortionless digital signals. In one embodiment, the replacement of the tones is done in a modem embodied in an Internet telephony Gateway/Terminal, such as in a network access server coupling a time division multiplexed telephone line to a packet-switched network. The replacement of the tones may also be performed in any suitable device that provides an interface between a time division multiplexed transmission medium and a packet switched data network, such as in the modems of a cellular telephone network to Internet network access server.