Paul C Schurr, 489019 County Lane 22, Sugar City, CO 81076

6021158, Feb 1, 2000

Oct 31, 1996

8/741777

Paul E. Schurr - Plano TX
Walter Y. Chen - Plano TX
Douglas B. Weiner - The Colony TX

Texas Instruments Incorporated - Dallas TX

H04B 336
H04L 2520

375211

A modem that operates selectively in the voice-band frequency band and at higher frequency bands is provided. This modem supports multiple line codes, like DMT and CAP. The modem uses a Digital Signal Processor (DSP), so that different existing ADSL line codes, such as Discrete MultiTone (DMT) and Carrierless AM/PM (CAP), can be implemented on the same hardware platform. The modem negotiates in real-time, for a desired line transmission rate to accommodate line condition and service-cost requirement. The line code and rate negotiation process may be implemented at the beginning of each communication session through the exchange of tones between the modems. A four-step MDSL modem initialization process is provided for line code and rate compatibility.

6055268, Apr 25, 2000

Jun 20, 1996

8/667267

William C. Timm - McKinney TX
Walter Y. Chen - Plano TX
Gene A. Frantz - Missouri City TX
Domingo G. Garcia - Plano TX
Xiaolin Lu - Dallas TX
Dennis G. Mannering - Garland TX
Michael O. Polley - Garland TX
Terence J. Riley - Rockwall TX
Donald P. Shaver - Dallas TX
Song Wu - Dallas TX
Alan Gatherer - Richardson TX
Paul E. Schurr - Plano TX
Douglas B. Weiner - The Colony TX

Texas Instruments Incorporated - Dallas TX

H03H 730
H03H 740
H03K 5159

375229

A modem communication system with receiving and transmission paths includes a direct equalizer system having an adaptive filter (1532) in the transmission path to compensate for frequency distortion of the communication channel. The transmitter filter coefficients are adapted by a filter coefficient calculator (1528), under control of a data detector (1526) which detects incoming data in the receiving path. A switch (1534) is controlled by status of a transmit output data buffer to multiplex either the training sequence or output data into the transmission path. When the buffer is idle, the training sequence generator (1540) is linked to a digital-to-analog (D/A) converter (1536) and line driver (1538). The receiving path includes an isolation switch (1520), a receiver amplifier (1522) and a slicer (1524). The receiver correlates the received training sequence with a known training sequence and updates the equalizer filter coefficients using an adaptation algorithm, such as a least mean squared algorithm.