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:
Jan. 16, 2007
Filed:
Jan. 22, 2003
Fuji Yang, Monmouth, NJ (US);
Fadi Saibi, Red Bank, NJ (US);
Chunbing Guo, Eatontown, NJ (US);
Kameran Azadet, Morganville, NJ (US);
Fuji Yang, Monmouth, NJ (US);
Fadi Saibi, Red Bank, NJ (US);
Chunbing Guo, Eatontown, NJ (US);
Kameran Azadet, Morganville, NJ (US);
Agere Systems Inc., Allentown, PA (US);
Abstract
A digitally programmable analog receive-side channel equalizer includes N identical zero-positioning (ZP) circuit pairs in a cascade, where the transfer function of one ZP circuit of each pair exhibits a positive zero and the transfer function of the other ZP circuit exhibits a negative zero. By digitally controlling tunable capacitors within the pairs, the equalizer's frequency response and gain can be adjusted, while a controllable (e.g., constant) group delay is maintained. The number of blocks in the cascade can be selected, and each block independently configured, to optimally compensate for high-frequency losses in a wide range of transmission environments. One implementation involves a T-block cascade with output taps that feed a T:1 output selector such that the output of the overall equalizer can be selected to be any one of these taps corresponding to a programmable equalizer of effective length N where N≦T.