Pulse or digital communications – Equalizers – Automatic
Reexamination Certificate
2007-02-13
2007-02-13
Bocure, Tesfaldet (Department: 2611)
Pulse or digital communications
Equalizers
Automatic
Reexamination Certificate
active
11146375
ABSTRACT:
Methods and apparatus for canceling pre-cursor inter-symbol interference (ISI) are disclosed. In a digital communication system, a significant amount of noise can be attributed to the pre-cursor portion of the ISI. In a receiver, it can be relatively difficult to compensate for pre-cursor ISI in part because pre-cursor ISI is a result of one or more symbols that have yet to arrive at the receiver. One embodiment removes a portion of this ISI by using multiple detection thresholds in parallel. For example, data slicing (generation of a hard decision) can include three thresholds. These thresholds for slicing include a positive offset, a negative offset and no offset. The positive and negative offsets can correspond to the expected pre-cursor component of the data channel for which the data is transmitted or to a fraction thereof. The path with the correctly-compensated ISI is selected later.
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Hissen Jurgen
Katic Ognjen
McAdam Mathew
Plasterer John
Zortea Anthony Eugene
Bocure Tesfaldet
Knobbe Martens Olson & Bear LLP
PMC-Sierra Inc.
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