Patent US5604769A successfully refreshed from Google Patents.
US5604769A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hybrid equalizer arrangement for use in data communications equipment
Assignee: Avago Technologies International Sales Pte Ltd
•
Filing: 1994-10-13
•
Granted: 1997-02-18
•
Expires: 2014-10-13
Abstract
Abstract A hybrid type of decision feedback equalizer (DFE) structure that approaches optimal DFE performance is described. The hybrid DFE includes both an intersymbol interference DFE (ISI-DFE) and a noise predictive DFE (NP-DFE). In particular, an adaptive feedforward filter section is followed by both an intersymbol interference (ISI) predictive filter and a noise predictive (NP) filter. The corresponding transmitter uses a precoder that utilizes optimal coefficient values, denoted as C(z), of the hybrid DFE structure. In particular, C(z) is equal to (1+I(z)) (1+N(z))-1, where, the notation I(z) and N(z), as known in the art, represent the resulting coefficient values after adaptation of the ISI-DFE and the NP-DFE, respectively.
Inventors
- 👤 Jin-Der Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:56
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/03; H04L25/03006; H04L25/03178; H04L25/03248; H04L25/03254; H04L25/03267; H04L25/38; H04L25/40; H04L25/49; H04L25/497; H04L25/4975; H04L25/03012; H04L25/03019; H04L25/03057; H04L25/03343; H04L2025/03433; H04L2025/03439; H04L2025/03445; H04L2025/03471; H04L2025/03484; H04L2025/03503; H04L2025/03777; H04L2025/03802; H04L2025/03808
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
107 words
Apparatus for use in data communications equipment, the apparatus comprising: precoding means responsive to a data signal for providing a sequence of precoded data symbols; and means for transmitting the sequence of precoded data symbols to a receiver; wherein the means for precoding further includes a feedback filter means for filtering the sequence of precoded data symbols, where the response function of the feedback filter means is equal to (1+I(z)) (1+N(z))-1, where I(z) is equal to a set of intersymbol interference decision feedback equalizer coefficients transmitted from the receiver and N(z) is equal to a set of noise predictive decision feedback equalizer coefficients transmitted from the receiver.
Claim 2
Dependent Claim
107 words
Apparatus for use in data communications equipment, the apparatus comprising: precoding means responsive to a data signal for providing a sequence of precoded data symbols; and means for transmitting the sequence of precoded data symbols to a receiver; wherein the means for precoding further includes a feedback filter means for filtering the sequence of precoded data symbols, where the response function of the feedback filter means is equal to (1+I(z)) (1+N(z))-1, where I(z) is equal to a set of intersymbol interference decision feedback equalizer coefficients transmitted from the receiver and N(z) is equal to a set of noise predictive decision feedback equalizer coefficients transmitted from the receiver.
Claim 3
Dependent Claim
106 words
Apparatus for use in data communications equipment, the apparatus comprising: a filter means responsive to a sequence of precoded data symbols for providing a feedback signal; and a mapper responsive to a signal representative of a difference between a data signal and the feedback signal for providing the sequence of precoded data symbols for transmission to a receiver; wherein the filter means has a response function equal to (1+I(z)) (1+N(z))-1, where I(z) is equal to a set of intersymbol interference decision feedback equalizer coefficients transmitted from the receiver and N(z) is equal to a set of noise predictive decision feedback equalizer coefficients transmitted from the receiver.
Claim 4
Dependent Claim
106 words
Apparatus for use in data communications equipment, the apparatus comprising: a filter means responsive to a sequence of precoded data symbols for providing a feedback signal; and a mapper responsive to a signal representative of a difference between a data signal and the feedback signal for providing the sequence of precoded data symbols for transmission to a receiver; wherein the filter means has a response function equal to (1+I(z)) (1+N(z))-1, where I(z) is equal to a set of intersymbol interference decision feedback equalizer coefficients transmitted from the receiver and N(z) is equal to a set of noise predictive decision feedback equalizer coefficients transmitted from the receiver.
Claim 5
Independent Claim
99 words
A method for use in data communications equipment, the method comprising the steps of: precoding a data signal to provide a sequence of precoded data symbols; and transmitting the sequence of precoded data symbols to a receiver; wherein the precoding further includes a step of filtering the sequence of precoded data symbols in accordance with a filter response function equal to (1+I(z)) (1+N(z))-1, where I(z) is equal to a set of intersymbol interference decision feedback equalizer coefficients transmitted from the receiver and N(z) is equal to a set of noise predictive decision feedback equalizer coefficients transmitted from the receiver.
Claim 6
Independent Claim
99 words
A method for use in data communications equipment, the method comprising the steps of: precoding a data signal to provide a sequence of precoded data symbols; and transmitting the sequence of precoded data symbols to a receiver; wherein the precoding further includes a step of filtering the sequence of precoded data symbols in accordance with a filter response function equal to (1+I(z)) (1+N(z))-1, where I(z) is equal to a set of intersymbol interference decision feedback equalizer coefficients transmitted from the receiver and N(z) is equal to a set of noise predictive decision feedback equalizer coefficients transmitted from the receiver.
Claim 7
Independent Claim
69 words
A method for use in data communications equipment, the method comprising the steps of: receiving a set of intersymbol interference decision feedback equalizer coefficients, I(z), from a receiver; receiving a set of noise predictive decision feedback equalizer coefficients, N(z), transmitted from the receiver; precoding a data signal to provide a precoded data signal for transmission to the receiver, where the precoded data signal is a function of (1+I(z)) (1+N(z))-1.
Claim 8
Independent Claim
69 words
A method for use in data communications equipment, the method comprising the steps of: receiving a set of intersymbol interference decision feedback equalizer coefficients, I(z), from a receiver; receiving a set of noise predictive decision feedback equalizer coefficients, N(z), transmitted from the receiver; precoding a data signal to provide a precoded data signal for transmission to the receiver, where the precoded data signal is a function of (1+I(z)) (1+N(z))-1.
Claim 9
Independent Claim
112 words
A method for use in data communications equipment, the method comprising the steps of: receiving a set of intersymbol interference decision feedback equalizer coefficients, I(z), from a receiver; receiving a set of noise predictive decision feedback equalizer coefficients, N(z), transmitted from the receiver; filtering a sequence of precoded data symbols to provide a feedback signal; and mapping a signal representative of a difference between a data signal and the feedback signal to provide the sequence of precoded data symbols; and transmitting the sequence of precoded data symbols to the receiver; wherein the filtering step filters the sequence of precoded data symbols in accordance with a filter response function equal to (1+I(z)) (1+N(z))-1.
Claim 10
Independent Claim
112 words
A method for use in data communications equipment, the method comprising the steps of: receiving a set of intersymbol interference decision feedback equalizer coefficients, I(z), from a receiver; receiving a set of noise predictive decision feedback equalizer coefficients, N(z), transmitted from the receiver; filtering a sequence of precoded data symbols to provide a feedback signal; and mapping a signal representative of a difference between a data signal and the feedback signal to provide the sequence of precoded data symbols; and transmitting the sequence of precoded data symbols to the receiver; wherein the filtering step filters the sequence of precoded data symbols in accordance with a filter response function equal to (1+I(z)) (1+N(z))-1.
References Cited (Backward Citations)
US5249200A
Cited
US5455839A
Cited
US5388124A
Cited
US5488633A
Cited
US5446758A
Cited
US5414733A
Cited
US5513216A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-02-18 | 2000-08-19 | 2001-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-02-18 | 2004-08-19 | 2005-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-02-18 | 2008-08-19 | 2009-02-18 | $7700.00 | Window Closed / Lapsed |