Patent US5844947A successfully refreshed from Google Patents.
US5844947A
Expired / Lapsed
US
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Viterbi decoder with reduced metric computation
Assignee: Avago Technologies International Sales Pte Ltd
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Filing: 1996-12-23
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Granted: 1998-12-01
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Expires: 2016-12-23
Abstract
Abstract There is disclosed a method and apparatus for computing branch metrics that are combinations of autocorrelation and cross correlation terms are constructed by first calculating and storing components of the autocorrelation and cross correlation terms at a symbol instant. Once calculated and stored, predetermined ones of the autocorrelation components and the cross correlation components are selected. The selected autocorrelation components and cross correlation components, or their inverse as predetermined, are combined to produce a branch metric. Other predetermined combinations of the stored components of autocorrelation and cross correlation terms, or their inverse, are combined to produce other branch metrics at the same symbol instant. All branch metrics associated with the symbol instant can be calculated in this manner. The components of the autocorrelation terms and cross correlation terms associated with the next symbol instant are calculated and stored, and the process of generating the branch metrics repeated.
Inventors
- 👤 Richard Adam Cesari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:50
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/004; H04L1/0045; H04L1/0052; H04L1/0053; H03; H03M; H03M13/00; H03M13/37; H03M13/39; H03M13/3961; H03M13/41; H03M13/4107; H03M13/65; H03M13/6502; H04L1/0054
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
88 words
A method for determining a plurality of branch metrics at a symbol instant that are comprised of autocorrelation terms and cross correlation terms, including the steps of generating components of the autocorrelation terms, storing the components of the autocorrelation terms, generating components of the cross correlation terms, storing the components of the cross correlation terms, characterized by: selecting predetermined ones of the autocorrelation components and the cross correlation components, and combining the selected autocorrelation components and cross correlation components in a predetermined manner to produce a branch metric.
Claim 2
Independent Claim
88 words
A method for determining a plurality of branch metrics at a symbol instant that are comprised of autocorrelation terms and cross correlation terms, including the steps of generating components of the autocorrelation terms, storing the components of the autocorrelation terms, generating components of the cross correlation terms, storing the components of the cross correlation terms, characterized by: selecting predetermined ones of the autocorrelation components and the cross correlation components, and combining the selected autocorrelation components and cross correlation components in a predetermined manner to produce a branch metric.
Claim 3
Dependent Claim
23 words
The method as recited in claim 1, further characterized the step of: repeating the selecting and combining steps to produce another branch metric.
Claim 4
Dependent Claim
127 words
An integrated circuit including a branch metric calculation circuit, comprising: a circuit for generating components of autocorrelation terms; at least one register for receiving and storing components of the autocorrelation terms; a circuit for generating components of cross correlation terms; at least one register for receiving and storing components of the cross correlation terms; a selection circuit for selecting predetermined ones of the autocorrelation components and the cross correlation components stored in said at least one registers; a selective inverter circuit for selectively inverting predetermined ones of the selected auto correlation components and cross correlation components; and a combining circuit for receiving the selected auto correlation components and cross correlation components and for combining the selected autocorrelation components and cross correlation components to produce a branch metric.
Claim 5
Dependent Claim
127 words
An integrated circuit including a branch metric calculation circuit, comprising: a circuit for generating components of autocorrelation terms; at least one register for receiving and storing components of the autocorrelation terms; a circuit for generating components of cross correlation terms; at least one register for receiving and storing components of the cross correlation terms; a selection circuit for selecting predetermined ones of the autocorrelation components and the cross correlation components stored in said at least one registers; a selective inverter circuit for selectively inverting predetermined ones of the selected auto correlation components and cross correlation components; and a combining circuit for receiving the selected auto correlation components and cross correlation components and for combining the selected autocorrelation components and cross correlation components to produce a branch metric.
Claim 6
Dependent Claim
16 words
The integrated circuit as recited in claim 3, wherein the selection circuit includes a look-up table.
Claim 7
Dependent Claim
15 words
The integrated circuit as recited in claim 3, wherein the combining circuit is an adder.
Claim 8
Dependent Claim
32 words
The integrated circuit as recited in claim 3 wherein the selective inverter circuit provides as an output a positive or a negative version of the input depending upon a control select input.
Claim 9
Dependent Claim
25 words
The integrated circuit as recited in claim 3, wherein the selection circuit selects all of the autocorrelation components and all of the cross correlation components.
Claim 10
Dependent Claim
15 words
The integrated circuit as recited in claim 3 further comprising at least one rotate circuit.
Claim 11
Dependent Claim
130 words
An integrated circuit comprising: a circuit for generating components of autocorrelation terms; a circuit for generating components of cross correlation terms; a circuit for combining autocorrelation components and cross correlation components; at least two registers for receiving and storing components of the autocorrelation terms; at least two registers for receiving and storing components of the cross correlation terms; a selection circuit for selecting predetermined ones of the autocorrelation components and the cross correlation components stored in said at least two registers; a selective circuit for selectively inverting predetermined ones of the selected auto correlation components and cross correlation components; and a combining circuit for receiving the selected auto correlation components and cross correlation components and for combining the selected autocorrelation components and cross correlation components to produce a branch metric.
Claim 12
Dependent Claim
130 words
An integrated circuit comprising: a circuit for generating components of autocorrelation terms; a circuit for generating components of cross correlation terms; a circuit for combining autocorrelation components and cross correlation components; at least two registers for receiving and storing components of the autocorrelation terms; at least two registers for receiving and storing components of the cross correlation terms; a selection circuit for selecting predetermined ones of the autocorrelation components and the cross correlation components stored in said at least two registers; a selective circuit for selectively inverting predetermined ones of the selected auto correlation components and cross correlation components; and a combining circuit for receiving the selected auto correlation components and cross correlation components and for combining the selected autocorrelation components and cross correlation components to produce a branch metric.
Claim 13
Dependent Claim
16 words
The integrated circuit as recited in claim 9, wherein the selection circuit includes a look-up table.
Claim 14
Dependent Claim
15 words
The integrated circuit as recited in claim 9, wherein the combining circuit is an adder.
Claim 15
Dependent Claim
31 words
The integrated circuit as recited in claim 9, wherein the selective inverter circuit provides as an output positive or a negative version of the input depending upon a control select input.
Claim 16
Dependent Claim
25 words
The integrated circuit as recited in claim 9, wherein the selection circuit selects all of the autocorrelation components and all of the cross correlation components.
Claim 17
Dependent Claim
15 words
The integrated circuit as recited in claim 9, further comprising at least one rotate circuit.
Claim 18
Dependent Claim
120 words
A receiver, comprising: a circuit for generating components of autocorrelation terms; at least one register for receiving and storing components of the autocorrelation terms; a circuit for generating components of cross correlation terms; at least one register for receiving and storing components of the cross correlation terms; a selection circuit for selecting predetermined ones of the autocorrelation components and the cross correlation components stored in said at least one registers, a selective inverter circuit for selectively inverting predetermined ones of the selected auto correlation components and cross correlation components; and a combining circuit for receiving the selected auto correlation components and cross correlation components and for combining the selected autocorrelation components and cross correlation components to produce a branch metric.
Claim 19
Dependent Claim
120 words
A receiver, comprising: a circuit for generating components of autocorrelation terms; at least one register for receiving and storing components of the autocorrelation terms; a circuit for generating components of cross correlation terms; at least one register for receiving and storing components of the cross correlation terms; a selection circuit for selecting predetermined ones of the autocorrelation components and the cross correlation components stored in said at least one registers, a selective inverter circuit for selectively inverting predetermined ones of the selected auto correlation components and cross correlation components; and a combining circuit for receiving the selected auto correlation components and cross correlation components and for combining the selected autocorrelation components and cross correlation components to produce a branch metric.
Claim 20
Dependent Claim
15 words
A receiver as recited in claim 15, wherein the selection circuit includes a look-up table.
Claim 21
Dependent Claim
14 words
A receiver as recited in claim 15, wherein the combining circuit is an adder.
Claim 22
Dependent Claim
31 words
A receiver as recited in claim 15 wherein the selective inverter circuit provides as an output a positive or a negative version of the input depending upon a control select input.
Claim 23
Dependent Claim
24 words
A receiver as recited in claim 15, wherein the selection circuit selects all of the autocorrelation components and all of the cross correlation components.
Claim 24
Dependent Claim
16 words
A receiver as recited in any of claim 15, further comprising at least one rotate circuit.
Claim 25
Dependent Claim
11 words
A receiver as recited in claim 15, further comprising a transmitter.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-11-30 | 2002-06-01 | 2002-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-30 | 2006-06-01 | 2006-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-30 | 2010-06-01 | 2010-12-01 | $7700.00 | Window Closed / Lapsed |