Method And System For Slicing A Communication Signal

• US 20100027709A1
• Filed: 10/14/2009
• Published: 02/04/2010
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: Intersil Americas LLC (Renesas Electronics Corporation)
• Original Assignee: Quellan, Inc. (Renesas Electronics Corporation)
• Inventors: Pelard, Cattalen, Kim, Andrew Joo, Gebara, Edward
• Granted Patent: US 8,576,939 B2
• Time in Patent Office: Days
• US Class Current: 375/287
• CPC Class Codes: H04L 25/03057 with a recursive structure H04L25/03031 takes precedence
• CPC Class Codes: H04L 25/03312 Arrangements specific to the provision of output signals

Abstract

A slicer can receive a communication signal having a level or amplitude that is between two discrete levels of a multilevel digital communication scheme. The slicer can compare the communication signal to a plurality of references such that multiple comparisons proceed essentially in parallel. A summation node can add the results of the comparisons to provide an output signal set to one of the discrete levels. The slicer can process the communication signal and provide the output signal on a symbol-by-symbol basis. A decision feedback equalizer (“DFE”) can comprise the slicer. A feedback circuit of the DFE can delay and scale the output signal and apply the delayed and scaled signal to the communication signal to reduce intersymbol interference (“ISI”).

Claims

1-20. -20. (canceled)

21. A method for processing a communication signal that comprises a first signal segment representing a first discrete unit of information and adjoining a second signal segment representing a second discrete unit of information, the method comprising the steps of:

providing a first signal in response to a first comparator comparing the first signal segment to a first threshold;

providing a second signal in response to a second comparator comparing the first signal segment to a second threshold;

providing a third signal in response to applying selected levels of delay and gain to a summation of the first signal and the second signal; and

applying the third signal to the second signal segment to compensate for interference on the second signal segment that is due to transfer of energy from the first signal segment to the second signal segment.

22. The method of claim 21, wherein the first discrete unit of information is a first symbol and the second discrete unit of information is a second symbol immediately following the first symbol.

23. The method of claim 21, wherein each of the first signal segment and the second signal segment deviates substantially from every level of a multilevel communication scheme that uniformly applies to the first signal segment and the second signal segment.

24. A method for processing a communication signal with a signal processing circuit, wherein the communication signal conveys information using a multilevel communication scheme, the method comprising the steps of:

generating a plurality of comparison signals based on comparing an amplitude of the communication signal to a plurality of references, the amplitude between two adjacent levels of the multilevel communication scheme and substantially deviating from each of the two adjacent levels; and

setting an output signal to one of the two adjacent levels in response to adding the plurality of comparison signals to one another.

25. The method of claim 24, wherein the communication signal comprises a series of symbols, and wherein the method further comprises performing the generating step and the setting step for each symbol in the series.

26. The method of claim 24, wherein the multilevel communication scheme comprises the two adjacent levels and at least one additional level.

27. The method of claim 24, wherein setting the output signal to one of the two adjacent levels comprises correcting for intersymbol interference.

28. The method of claim 24, wherein a first symbol of the communication signal comprises the amplitude, and wherein the setting step comprises compensating for interference on the first symbol caused by a second symbol that is temporally adjacent the first symbol.

29. The method of claim 24, wherein a symbol of the communication signal comprises the amplitude, and wherein setting the output signal to one of the adjacent levels comprises correcting interference on the symbol due to another symbol that is next to the symbol in time.

30. The method of claim 24, wherein the communication signal comprises a series of signal segments, each signal segment conveying information and imposing interference on an adjacent signal segment, and

wherein the setting step comprises correcting the interference.

31. The method of claim 24, wherein the amplitude deviates from the two adjacent levels due to interference and is between the two adjacent levels due to interference.

32. The method of claim 24, further comprising the step of scaling each of the plurality of comparison signals, wherein adding the plurality of comparison signals to one another comprises adding the scaled comparison signals to one another.

33. A method for processing a communication signal comprising a first signal segment that represents a first symbol and that immediately precedes a second signal segment representing a second symbol, the method comprising:

processing the first signal segment with a plurality of comparators connected to a corresponding plurality of references, each comparator producing a respective output;

setting a signal to a discrete intensity in response to summing the respective outputs;

delaying and scaling the signal; and

applying the delayed and scaled signal to the second signal segment to correct interference on the second signal segment.

34. The method of claim 33, wherein correcting interference on the second signal segment comprises correcting intersymbol interference.

35. The method of claim 33, wherein correcting interference on the second signal segment comprises correcting interference that the first signal segment has imposed on the second signal segment.

36. The method of claim 33, wherein the communication signal further comprises a third signal segment that follows the second signal segment, and

wherein the method further comprises the steps of:

processing the second signal segment with the plurality of comparators, each comparator producing a respective second output;

generating a second signal in response to summing the respective second outputs;

delaying and scaling the second signal; and

applying the delayed and scaled second signal to the third signal segment to correct interference on the third signal segment.

37. The method of claim 33, wherein a multilevel communication scheme applies consistently to the first signal segment and the second signal segment.

38. The method of claim 33, wherein the plurality of comparators comprises three comparators.

39. The method of claim 33, wherein the first signal segment occupies a first symbol period, and wherein the second signal segment occupies a second symbol period.

40. The method of claim 33, wherein the first signal segment comprises an amplitude that deviates substantially from every level of a multilevel communication scheme that applies to the first signal segment and that applies to the second signal segment.