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:
Oct. 18, 2011
Filed:
Dec. 31, 2007
Pervez M. Aziz, Dallas, TX (US);
Adam B. Healey, Newburyport, MA (US);
Mohammad S. Mobin, Orefield, PA (US);
Gary E. Schiessler, Allentown, PA (US);
Gregory W. Sheets, Breinigsville, PA (US);
Lane A. Smith, Easton, PA (US);
Paul H. Tracy, Lehigh, PA (US);
Geoffrey Zhang, Allentown, PA (US);
Pervez M. Aziz, Dallas, TX (US);
Adam B. Healey, Newburyport, MA (US);
Mohammad S. Mobin, Orefield, PA (US);
Gary E. Schiessler, Allentown, PA (US);
Gregory W. Sheets, Breinigsville, PA (US);
Lane A. Smith, Easton, PA (US);
Paul H. Tracy, Lehigh, PA (US);
Geoffrey Zhang, Allentown, PA (US);
Agere System Inc., Allentown, PA (US);
Abstract
Methods and apparatus are provided for improving the jitter tolerance in an SFP limit amplified signal. Jitter tolerance is improved in a communications receiver by applying a received signal to an SFP limiting amplifier; and applying an output of the SFP limiting amplifier to a low pass filter to improve the jitter tolerance. The low pass filter optionally applies a programmable amount of attenuation to high frequency components of the output. The low pass filter slew rate controls (i.e., rotates) a data eye representation of the received signal to increase the data eye representation along a time axis. The noise margin of the received signal can optionally be improved by applying an output of the low pass filter to an all pass filter. A slew rate controller can evaluate the data eye statistics to determine a setting for the low pass filter.