Patent Number: 6,480,533

Title: Method and apparatus for receiving control signals in a data communication system having a fully digital communication channel

Abstract: A modem system having two modem devices digitally connected to a digital telephone network includes an inband control signal channel. The inband control signal channel is formed by using the most significant bit position of every sixth transmitted codeword for the transmission of control data. The control signal includes a predetermined header section that is monitored by the receiving modem to maintain frame synchronization and to correct for digital frame slippage. The control signal also includes a number of control data packets that contain information related to the initiation of control procedures such as rate renegotiations and retraining requests. The disclosed inband transmission techniques may additionally (or alternatively) be utilized to define a secondary data channel.

Inventors: Chu; Keith (Laguan Niguel, CA), Olafsson; Sverrir (Reykjavik, IS)

Assignee: Conexant Systems, Inc.

International Classification: H04M 11/06 (20060101); H04L 25/49 (20060101); H04J 3/12 (20060101); H04B 001/38 (); H04L 005/16 ()

Expiration Date: 11/12/2019