Method of and apparatus for performing line characterization in a subscriber ...

(54) METHOD OF AND APPARATUS FOR

PERFORMING LINE CHARACTERIZATION
IN A SUBSCRIBER LINE COMMUNICATION
SYSTEM

(75) Inventors: Edward S. Zuranski, Largo; Kenneth
D. Ko, Clearwater; Jamal Haque,
Tampa; Shrenik P. Patravali; Manuel
I. Rodriguez, both ol St. Petersburg;
Keith A. Souders, Tampa; Anthony A.
Tzouris, Clearwater, all of FL (US)

(73) Assignee: Conexant Systems, Inc., Newport Beach, CA (US)

( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 19 days.

(21) Appl. No.: 09/028,023

(22) Filed: Feb. 23, 1998

Related U.S. Application Data

(63) Continuation-in-part of application No. 08/943,484, filed on Oct. 3, 1997, now Pat. No. 6,101,216.

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OTHER PUBLICATIONS

Patent application for "Digital Subscriber Line Modem Utilizing Echo Cancellation to Reduce Near-End Cross-Talk Noise", filed Feb. 23,1998, inventors: Zuranski, et al., Serial No. not yet assigned.

(List continued on next page.)

Primary Examiner—Tesealdet Bocure

(74) Attorney, Agent, or Firm—Foley & Lardner

(57) ABSTRACT

A digital subscriber line communication system does not require the use of a plain old telephone service (POTS) splitter in the resident's home. Digital signal processing techniques are utilized to adapt to varying subscriber line conditions due to POTS telephone equipment. The digital signal processing techniques eliminate the need for a splitter by reducing susceptibility to distortion due to varying subscriber line characteristics. The digital subscriber line modem characterizes the subscriber line under a variety of conditions. The digital subscriber line modem includes a control circuit which performs rapid retrain operation utilizing line characterization information.

19 Claims, 7 Drawing Sheets

U.S. PATENT DOCUMENTS

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OTHER PUBLICATIONS

Patent application for "Method of and Apparatus for Performing Line Characterization in a Non-Idle Mode in a Subscriber Line Communication System", filed Feb. 23, 1998, inventors: Souders, et al., Serial No. not yet assigned. Patent application for "Communication System Utilizing Reed-Solomon Code to Achieve Auto Frame Synchronization Acquisition", filed Feb. 23, 1998, inventors: Zuranski, et al., Serial No. not yet assigned.

* cited by examiner