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:
Feb. 21, 2006
Filed:
Aug. 06, 2003
Youssef Abdelilah, Holly Springs, NC (US);
Gordon Taylor Davis, Chapel Hill, NC (US);
Jeffrey Haskell Derby, Chapel Hill, NC (US);
Ajay Dholakia, Gattikon, CH;
Evangelos Stavros Eleftheriou, Zurich, CH;
Robert F. H. Fischer, Erlangen, DE;
Dongming Hwang, Cary, NC (US);
Fredy D. Neeser, Langnau, CH;
Malcolm Scott Ware, Raleigh, NC (US);
Hua YE, Durham, NC (US);
Youssef Abdelilah, Holly Springs, NC (US);
Gordon Taylor Davis, Chapel Hill, NC (US);
Jeffrey Haskell Derby, Chapel Hill, NC (US);
Ajay Dholakia, Gattikon, CH;
Evangelos Stavros Eleftheriou, Zurich, CH;
Robert F. H. Fischer, Erlangen, DE;
Dongming Hwang, Cary, NC (US);
Fredy D. Neeser, Langnau, CH;
Malcolm Scott Ware, Raleigh, NC (US);
Hua Ye, Durham, NC (US);
Lenovo (Singapore) Pte. Ltd., , SG;
Abstract
Receivers, methods, and computer program products can be used to demodulate a data signal transmitted from a digital source, which has a network sampling rate that is synchronized with a network clock. In an illustrative embodiment, a receiver includes a two-stage interpolator that receives digital samples of the data signal as an input and produces an interpolated digital sample stream to be filtered by an adaptive fractionally spaced decision feedback equalizer. The digital samples received in the interpolator are synchronized with a local clock; however, the interpolated sample stream is synchronized with the network clock. A slicer generates symbols for the samples output from the decision feedback equalizer by comparing the samples with a reference signaling alphabet. The receiver can be used in a V.90 client modem to demodulate pulse code modulated (PCM) data transmitted as pulse amplitude modulated (PAM) signals from a digital network. In addition, the receiver is compatible with legacy analog modem front ends and transmitters. The two-stage interpolator allows the timing synchronization to be performed with extremely fine granularity, which can be useful in PCM modems that typically require relatively high signal to noise ratios.