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Patent US5434884A successfully refreshed from Google Patents.
US5434884A
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Apparatus and method for equalizing for amplitude jitter
Assignee: Motorola Solutions Inc
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Filing: 1994-10-04
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Granted: 1995-07-18
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Expires: 2014-10-04
Abstract
Abstract A modem (100) includes an equalizer for equalizing a received signal (10) for amplitude jitter distortion. The received signal includes modulated symbols based on a predetermined constellation of points, each point representing a symbol. The modem first extracts a modulated symbol to provide an extracted symbol, R(k), which includes amplitude jitter distortion. The modem then identifies a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol. Further, the modem determines an error signal (76) based on the amplitude jitter distortion, and then uses the error signal to compensate subsequent extracted symbols for the amplitude jitter distortion.
Inventors
- 👤 Mickey C. Rushing
- 👤 Steven R. Blackwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:39
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/32; H04L27/34; H04L27/38; H04L27/3845; H04L27/3854; H04L27/3872
Claims Analysis
Total Claims: 71
Claim 1
Independent Claim
139 words
A modem for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modulated symbols including amplitude jitter distortion, the modem comprising: means for extracting modulated symbols to provide an extracted symbol, R(k); identifying means for identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criterion; determining means for determining a normalized error signal, E n (k), the normalized error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and compensating means responsive to the normalized error signal, the compensating means generating a compensating signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto.
Claim 2
Dependent Claim
139 words
A modem for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modulated symbols including amplitude jitter distortion, the modem comprising: means for extracting modulated symbols to provide an extracted symbol, R(k); identifying means for identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criterion; determining means for determining a normalized error signal, E n (k), the normalized error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and compensating means responsive to the normalized error signal, the compensating means generating a compensating signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto.
Claim 3
Dependent Claim
77 words
The modem of claim 1 wherein R(k) and P n (k) are complex signals including inphase and quadrature components, wherein the normalized error signal, E n (k), is derived from an error signal, E(k), the error signal E(k) being based on the difference between R(k) and P n (k), and wherein the determining means further comprises projecting means for projecting the error signal E(k) onto P n (k) to derive an unnormalized error signal, E a (k).
Claim 4
Dependent Claim
41 words
The modem of claim 2 wherein the determining means further comprises means for normalizing the unnormalized error signal to the absolute value of P n (k) to form the normalized error signal E n (k) for use by the compensating means.
Claim 5
Dependent Claim
60 words
The modem of claim 2 wherein the determining means further comprises means for deriving the unnormalized error signal, E a (k), based on the following equation: ##EQU5## where: E x =the inphase component of E(k); E y =the quadrature component of E(k); P x =the inphase component of P n (k); P y =the quadrature component of P n (k).
Claim 6
Dependent Claim
27 words
The modem of claim 2 wherein the determining means further comprises means for deriving the normalized error signal, E n (k), based on the following equation: ##EQU6##
Claim 7
Dependent Claim
41 words
The modem of claim 1 wherein the compensating means further comprises an amplitude jitter tracker responsive to the normalized error signal, the amplitude jitter tracker including means to provide a compensating signal for compensating the at least one subsequent extracted symbol.
Claim 8
Dependent Claim
42 words
The modem of claim 6 wherein the amplitude jitter tracker further comprises means, for matching the compensating signal to the amplitude jitter distortion of the extracted symbols such that compensation thereof converges the corresponding normalized error signals to a steady state value.
Claim 9
Dependent Claim
13 words
The modem of claim 7 wherein the steady state value is substantially zero.
Claim 10
Dependent Claim
76 words
The modern of claim 6 wherein the amplitude jitter distortion includes at least one sinusoidal component having a sinusoidal component amplitude and a sinusoidal component frequency, and wherein the amplitude jitter tracker further comprises: providing means responsive to the error signal for providing a compensating signal frequency value and a compensating signal amplitude value; and combining means for combining the compensating signal frequency value and the compensating signal amplitude value to form a composite compensating signal.
Claim 11
Dependent Claim
46 words
The modern of claim 9 wherein the providing means further comprises means for matching the compensating signal frequency value to the sinusoidal component frequency such that compensation of subsequent extracted symbols with the compensating signal frequency value converges the corresponding normalized error signals to substantially zero.
Claim 12
Dependent Claim
15 words
The modem of claim 10 wherein the providing means further comprises a phase locked loop.
Claim 13
Dependent Claim
46 words
The modem of claim 9 wherein the providing means further comprises means for matching the compensating signal amplitude value to the sinusoidal component amplitude such that compensation of subsequent extracted symbols with the compensating signal amplitude value converges the corresponding normalized error signals to substantially zero.
Claim 14
Dependent Claim
15 words
The modem of claim 12 wherein the providing means further comprises an adaptive update filter.
Claim 15
Dependent Claim
36 words
The modem of claim 12 wherein the providing means further comprises means for correlating the normalized error signal with the compensating signal frequency value to substantially remove any sinusoidal variations from the compensating signal amplitude value.
Claim 16
Dependent Claim
30 words
The modem of claim 9 wherein the combining means further comprises means for multiplying the compensating signal frequency value by the compensating signal amplitude value to provide the compensating signal.
Claim 17
Dependent Claim
44 words
The modem of claim 6 wherein the compensating means further comprises means for multiplying the extracted symbol with a signal based on the compensating signal to provide a compensated extracted symbol for use by the identifying means to identify the signal point corresponding thereto.
Claim 18
Dependent Claim
34 words
The modem of claim 1 wherein the compensating means further comprises linear predictor means responsive to the normalized error signal for providing the compensating signal for compensating the at least one subsequent extracted symbol.
Claim 19
Dependent Claim
139 words
The modern of claim 17 wherein the linear predictor means further comprises: means for compensating the normalized error signal with a signal based on the compensating signal to provide a first intermediate error signal, E A (k); means for combining the first intermediate error signal with a delayed compensating signal to provide a second intermediate error signal; delay line means having a plurality of tapped delay stages, the delay line means arranged to conduct the second intermediate error signal through the plurality of tapped delay stages thereof, the contents of each stage being operated on by a corresponding stage gain to provide a corresponding plurality of tapped output signals; means for updating the plurality of stage gains based on the first intermediate error signal; and means for combining the plurality of tapped output signals to provide the compensating signal.
Claim 20
Dependent Claim
58 words
The modem of claim 17 further comprising equalizing means for equalizing the extracted symbols to provide equalized extracted symbols for use by the identifying means, error signal compensating means for compensating the normalized error signal with the compensating signal to provide a compensated error signal, and means for adjusting the equalizing means based on the compensated error signal.
Claim 21
Dependent Claim
34 words
The modem of claim 19 wherein the error signal compensating means further comprises means for multiplying the normalized error signal with a signal based on the compensating signal to provide a compensated error signal.
Claim 22
Dependent Claim
153 words
An equalizer arranged for use with a modem, the modem arranged for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modulated symbols including amplitude jitter distortion, the modem having means for extracting modulated symbols to provide an extracted symbol, R(k), and having identifying means for identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criterion, the equalizer comprising: determining means for determining a normalized error signal, E n (k), the normalized error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and compensating means responsive to the normalized error signal, the compensating means generating a compensating signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto.
Claim 23
Dependent Claim
153 words
An equalizer arranged for use with a modem, the modem arranged for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modulated symbols including amplitude jitter distortion, the modem having means for extracting modulated symbols to provide an extracted symbol, R(k), and having identifying means for identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criterion, the equalizer comprising: determining means for determining a normalized error signal, E n (k), the normalized error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and compensating means responsive to the normalized error signal, the compensating means generating a compensating signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto.
Claim 24
Dependent Claim
76 words
The equalizer of claim 21 wherein R(k) and P n (k) are complex signals, including inphase and quadrature components, wherein the normalized error signal, E n (k), is derived from an error signal, E(k), the error signal E(k) being based on the difference between R(k) and P n (k), and wherein the determining means further comprises projecting means for projecting the error signal E(k)onto P n (k) to derive an unnormalized error signal, E a (k).
Claim 25
Dependent Claim
41 words
The equalizer of claim 22 wherein the determining means further comprises means for normalizing the unnormalized error signal to the absolute value of P n (k) to form the normalized error signal E n (k) for use by the compensating means.
Claim 26
Dependent Claim
60 words
The equalizer of claim 22 wherein the determining means further comprises means for deriving the unnormalized error signal, E a (k), based on the following equation: ##EQU7## where: E x =the inphase component of E(k); E y =the quadrature component of E(k); P x =the inphase component of P n (k); P y =the quadrature component of P n (k).
Claim 27
Dependent Claim
27 words
The equalizer of claim 24 wherein the determining means further comprises means for deriving the normalized error signal, E n (k), based on the following equation: ##EQU8##
Claim 28
Dependent Claim
40 words
The equalizer of claim 21 wherein the compensating means comprises an amplitude jitter tracker responsive to the normalized error signal, the amplitude jitter tracker including means to provide a compensating signal for compensating the at least one subsequent extracted symbol.
Claim 29
Dependent Claim
42 words
The equalizer of claim 26 wherein the amplitude jitter tracker further comprises means for matching the compensating signal to the amplitude jitter distortion of the extracted symbols such that compensation thereof converges the corresponding normalized error signals to a steady state value.
Claim 30
Dependent Claim
13 words
The equalizer of claim 27 wherein the steady state value is substantially zero.
Claim 31
Dependent Claim
76 words
The equalizer of claim 26 wherein the amplitude jitter distortion includes at least one sinusoidal component having a sinusoidal component amplitude and a sinusoidal component frequency, and wherein the amplitude jitter tracker further comprises: providing means responsive to the error signal for providing a compensating signal frequency value and a compensating signal amplitude value; and combining means for combining the compensating signal frequency value and the compensating signal amplitude value to form a composite compensating signal.
Claim 32
Dependent Claim
46 words
The equalizer of claim 29 wherein the providing means further comprises means for matching the compensating signal frequency value to the sinusoidal component frequency such that compensation of subsequent extracted symbols with the compensating signal frequency value converges the corresponding normalized error signals to substantially zero.
Claim 33
Dependent Claim
14 words
The equalizer of claim 30 wherein the providing means comprises a phase locked loop.
Claim 34
Dependent Claim
46 words
The equalizer of claim 29 wherein the providing means further comprises means for matching the compensating signal amplitude value to the sinusoidal component amplitude such that compensation of subsequent extracted symbols with the compensating signal amplitude value converges the corresponding normalized error signals to substantially zero.
Claim 35
Dependent Claim
14 words
The equalizer of claim 32 wherein the providing means comprises an adaptive update filter.
Claim 36
Dependent Claim
36 words
The equalizer of claim 32 wherein the providing means further comprises means for correlating the normalized error signal with the compensating signal frequency value to substantially remove any sinusoidal variations from the compensating signal amplitude value.
Claim 37
Dependent Claim
30 words
The equalizer of claim 29 wherein the combining means further comprises means for multiplying the compensating signal frequency value by the compensating signal amplitude value to provide the compensating signal.
Claim 38
Dependent Claim
44 words
The equalizer of claim 29 wherein the compensating means further comprises means for multiplying the extracted symbol with a signal based on the compensating signal to provide a compensated extracted symbol for use by the identifying means to identify the signal point corresponding thereto.
Claim 39
Dependent Claim
34 words
The equalizer of claim 21 wherein the compensating means further comprises linear predictor means responsive to the normalized error signal for providing the compensating signal for compensating the at least one subsequent extracted symbol.
Claim 40
Dependent Claim
138 words
The equalizer of claim 37 wherein the linear predictor means comprises: means for compensating the normalized error signal with a signal based on the compensating signal to provide a first intermediate error signal, E A (k); means for combining the first intermediate error signal with a delayed compensating signal to provide a second intermediate error signal; delay line means having a plurality of tapped delay stages, the delay line means arranged to conduct the second intermediate error signal through the plurality of tapped delay stages thereof, the contents of each stage being operated on by a corresponding stage gain to provide a corresponding plurality of tapped output signals; means for updating the plurality of stage gains based on the first intermediate error signal; and means for combining the plurality of tapped output signals to provide the compensating signal.
Claim 41
Dependent Claim
58 words
The equalizer of claim 37 further comprising equalizing means for equalizing the extracted symbols to provide equalized extracted symbols for use by the identifying means, error signal compensating means for compensating the normalized error signal with the compensating signal to provide a compensated error signal, and means for adjusting the equalizing means based on the compensated error signal.
Claim 42
Dependent Claim
34 words
The equalizer of claim 39 wherein the error signal compensating means further comprises means for multiplying the normalized error signal with a signal based on the compensating signal to provide a compensated error signal.
Claim 43
Independent Claim
152 words
A method of equalizing for amplitude jitter distortion in a data communication device arranged for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modulated symbols including the amplitude jitter distortion, the method of equalizing for the amplitude jitter comprising: (a) extracting modulated symbols to provide an extracted symbol, R(k); (b) identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criterion; (c) determining a normalized error signal, E n (k), the normalized error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and (d) compensating for the amplitude jitter by generating a compensating signal, responsive to the normalized error signal, for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to identifying the signal point corresponding thereto.
Claim 44
Independent Claim
152 words
A method of equalizing for amplitude jitter distortion in a data communication device arranged for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modulated symbols including the amplitude jitter distortion, the method of equalizing for the amplitude jitter comprising: (a) extracting modulated symbols to provide an extracted symbol, R(k); (b) identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criterion; (c) determining a normalized error signal, E n (k), the normalized error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and (d) compensating for the amplitude jitter by generating a compensating signal, responsive to the normalized error signal, for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to identifying the signal point corresponding thereto.
Claim 45
Dependent Claim
74 words
The method of claim 41 wherein R(k) and P n (k) are complex signals including inphase and quadrature components, and wherein the determining step (c) further comprises deriving the normalized error signal, E n (k), from an error signal, E(k), the error signal E(k) being based on the difference between R(k) and P n (k), and projecting the error signal E(k) onto P n (k) to device an unnormalized error signal, E a (k).
Claim 46
Dependent Claim
41 words
The method of claim 42 wherein the determining step (c) further comprises normalizing the unnormalized error signal to the absolute value of P n (k) to form the normalized error signal E n (k) for use in the compensating step (d).
Claim 47
Dependent Claim
59 words
The method of claim 42 wherein the determining step (c) further comprises deriving the unnormalized error signal, E a (k), based on the following equation: ##EQU9## where: E x =the inphase component of E(k); E y =the quadrature component of E(k); P x =the inphase component of P n (k); P y =the quadrature component of P n (k).
Claim 48
Dependent Claim
26 words
The method of claim 42 wherein the determining step (c) further comprises deriving the normalized error signal, E n (k), based on the following equation: ##EQU10##
Claim 49
Dependent Claim
41 words
The method of claim 41 wherein the compensating step (d) further comprises: (d1) tracking the amplitude jitter, responsively to the normalized error signal, the amplitude jitter tracking including providing a compensating signal for compensating the at least one subsequent extracted symbol.
Claim 50
Dependent Claim
40 words
The method of claim 46 wherein the amplitude jitter tracking further comprises; matching the compensating signal to the amplitude jitter distortion of the extracted symbols such that compensation thereof converges the corresponding normalized error signals to a steady state value.
Claim 51
Dependent Claim
13 words
The method of claim 47 wherein the steady state value is substantially zero.
Claim 52
Dependent Claim
74 words
The method of claim 46 wherein the amplitude jitter distortion includes at least one sinusoidal component having a sinusoidal component amplitude and a sinusoidal component frequency, and wherein the amplitude jitter tracking step (d1) further comprises: (d2) providing a compensating signal frequency value and a compensating signal amplitude value, responsive to the error signal; and (d3) combining the compensating signal frequency value and the compensating signal amplitude value to form a composite compensating signal.
Claim 53
Dependent Claim
45 words
The method of claim 49 wherein the providing step (d2) further comprises matching the compensating signal frequency value to the sinusoidal component frequency such that compensation of subsequent extracted symbols with the compensating signal frequency value converges the corresponding normalized error signals to substantially zero.
Claim 54
Dependent Claim
30 words
The method of claim 50 further comprising correlating the normalized error signal with the compensating signal frequency value to substantially remove any sinusoidal variations from the compensating signal amplitude value.
Claim 55
Dependent Claim
45 words
The method of claim 49 wherein the providing step (d2) further comprises matching the compensating signal amplitude value to the sinusoidal component amplitude such that compensation of subsequent extracted symbols with the compensating signal amplitude value converges the corresponding normalized error signals to substantially zero.
Claim 56
Dependent Claim
29 words
The method of claim 49 wherein the combining step (d3) further comprises multiplying the compensating signal frequency value by the compensating signal amplitude value to provide the compensating signal.
Claim 57
Dependent Claim
43 words
The method of claim 46 wherein the compensating step (d) further comprises multiplying the extracted symbol with a signal based on the compensating signal to provide a compensated extracted symbol for use in identifying step (b) to identify the signal point corresponding thereto.
Claim 58
Dependent Claim
34 words
The method of claim 41 wherein the compensating step (d) further comprises linear prediction, responsive to the normalized error signal, for providing the compensating signal for compensating the at least one subsequent extracted symbol.
Claim 59
Dependent Claim
114 words
The method of claim 55 wherein the linear prediction step further comprises: compensating the normalized error signal with a signal based on the compensating signal to provide a first intermediate error signal, E A (k); combining the first intermediate error signal with a delayed compensating signal to provide a second intermediate error signal; conducting the second intermediate error signal through a plurality of tapped delay stages, the contents of each stage being operated on by a corresponding stage gain to provide a corresponding plurality of tapped output signals; updating the plurality of stage gains based on the first intermediate error signal; and combining the plurality of tapped output signals to provide the compensating signal.
Claim 60
Dependent Claim
47 words
The method of claim 55 further comprising equalizing the extracted symbols to provide equalized extracted symbols in the identifying step (b), compensating the normalized error signal with the compensating signal to provide a compensated error signal, and adjusting the equalizing means based on the compensated error signal.
Claim 61
Dependent Claim
31 words
The method of claim 57 wherein the error signal compensation further comprises; multiplying the normalized error signal with a signal based on the compensating signal to provide a compensated error signal.
Claim 62
Dependent Claim
153 words
A modem for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modem including: means for extracting modulated symbols to provide an extracted symbol, R(k), the; extracted symbol including amplitude jitter distortion, identifying means for identifying a signal point P n (k) of the predetermined constellation of points corresponding to the extracted symbol, based on a predetermined criteria; determining means for determining an error signal, said error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; compensating means responsive to the error signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto; and the compensating means includes linear predictor means responsive to the error signal for providing a compensating signal for compensating at least one subsequent extracted symbol.
Claim 63
Dependent Claim
153 words
A modem for receiving a signal, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modem including: means for extracting modulated symbols to provide an extracted symbol, R(k), the; extracted symbol including amplitude jitter distortion, identifying means for identifying a signal point P n (k) of the predetermined constellation of points corresponding to the extracted symbol, based on a predetermined criteria; determining means for determining an error signal, said error signal being representative of the amplitude jitter distortion based on the extracted symbol and the signal point; compensating means responsive to the error signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto; and the compensating means includes linear predictor means responsive to the error signal for providing a compensating signal for compensating at least one subsequent extracted symbol.
Claim 64
Dependent Claim
131 words
The modern of claim 59 wherein the linear predictor means includes: means for compensating the error signal with a signal based on the compensating signal to provide an intermediate error signal; means for combining the intermediate error signal with a delayed compensating signal to provide a second intermediate error signal; delay line means having a plurality of tapped delay stages, the delay line means arranged to conduct the second intermediate error signal through the plurality of tapped delay stages thereof, the contents of each stage being operated on by a corresponding stage gain to provide a corresponding plurality of tapped output signals; means for updating the plurality of stage gains based on the intermediate error signal; and means for combining the plurality of tapped output signals to provide the compensating signal.
Claim 65
Dependent Claim
56 words
The modem of claim 59 including equalizing means for equalizing the extracted symbols to provide equalized extracted symbols for use by the identifying means, error signal compensating means for compensating the error signal with the compensating signal to provide a compensated error signal, and means for adjusting the equalizing means based on the compensated error signal.
Claim 66
Dependent Claim
32 words
The modem of claim 59 wherein the error signal compensating means includes means for multiplying the error signal with a signal based on the compensating signal to provide a compensated error signal.
Claim 67
Dependent Claim
164 words
An equalizer arranged for use with a modem, the modem arranged for receiving a signal transported by a channel, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modem including: means for extracting modulated symbols to provide an extracted symbol, R(k), the extracted symbol including amplitude jitter distortion, identifying means for identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criteria; the equalizer including: determining means for determining an error signal representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and compensating means responsive to the error signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto; and the compensating means including linear predictive means responsive to the error signal for providing a compensating signal for compensating at least one subsequent extracted symbol.
Claim 68
Dependent Claim
164 words
An equalizer arranged for use with a modem, the modem arranged for receiving a signal transported by a channel, the signal including modulated symbols based on a predetermined constellation of points, each point representing a symbol, the modem including: means for extracting modulated symbols to provide an extracted symbol, R(k), the extracted symbol including amplitude jitter distortion, identifying means for identifying a signal point P n (k) of the predetermined constellation corresponding to the extracted symbol, based on a predetermined criteria; the equalizer including: determining means for determining an error signal representative of the amplitude jitter distortion based on the extracted symbol and the signal point; and compensating means responsive to the error signal for compensating at least one subsequent extracted symbol for the amplitude jitter distortion prior to the identifying means identifying the signal point corresponding thereto; and the compensating means including linear predictive means responsive to the error signal for providing a compensating signal for compensating at least one subsequent extracted symbol.
Claim 69
Dependent Claim
131 words
The equalizer of claim 63 wherein the linear predictor means includes: means for compensating the error signal with a signal based on the compensating signal to provide an intermediate error signal; means for combining the intermediate error signal with a delayed compensating signal to provide a second intermediate error signal; delay line means having a plurality of tapped delay stages, the delay line means arranged to conduct the second intermediate error signal through the plurality of tapped delay stages thereof, the contents of each stage being operated on by a corresponding stage gain to provide a corresponding plurality of tapped output signals; means for updating the plurality of stage gains based on the intermediate error signal; and means for combining the plurality of tapped output signals to provide the compensating signal.
Claim 70
Dependent Claim
56 words
The equalizer of claim 63 including equalizing means for equalizing the extracted symbols to provide equalized extracted symbols for use by the identifying means, error signal compensating means for compensating the error signal with the compensating signal to provide a compensated error signal, and means for adjusting the equalizing means based on the compensated error signal.
Claim 71
Dependent Claim
32 words
The equalizer of claim 63 wherein the error signal compensating means includes means for multiplying the error signal with a signal based on the compensating signal to provide a compensated error signal.
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