Patent US5581581A successfully refreshed from Google Patents.
US5581581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Viterbi equalizer
Assignee: Sony Corp
•
Filing: 1995-12-01
•
Granted: 1996-12-03
•
Expires: 2015-12-01
Abstract
Abstract A Viterbi equalizer can provide an accurate equalizing characteristic. This Viterbi equalizer comprises a synchronizing signal data detecting circuit for detecting a synchronizing signal data portion from a reception signal data series, a transmission line characteristic estimating circuit for modelling an impulse response between a transmitter and a receiver by comparing a synchronizing signal data detected by the synchronizing signal data detecting circuit with a reference signal, and a decoding circuit for decoding a transmission data series by using a Viterbi algorithm on the basis of a transmission model obtained from the transmission line characteristic estimating circuit.
Inventors
- 👤 Teruo Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:50
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/0202; H04L25/024; H04L25/0242; H04L25/0246; H04L25/0212
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
120 words
A Viterbi equalizer, comprising: (a) synchronizing signal data detecting means for detecting only a synchronizing signal data portion from a reception signal data series; (b) transmission line characteristic estimating means for modeling an impulse response between a transmitter and a receiver by comparing only the synchronizing signal data portion detected by said synchronizing signal data detecting means with a reference signal; (c) decoding means for decoding the reception signal data series by using a Viterbi algorithm on the basis of the modeled impulse response obtained from said transmission line characteristic estimating means; and (d) a normalization circuit means for avoiding an overflow which takes place when a path metric is calculated in an error correction process utilizing the Viterbi algorithm.
Claim 2
Dependent Claim
120 words
A Viterbi equalizer, comprising: (a) synchronizing signal data detecting means for detecting only a synchronizing signal data portion from a reception signal data series; (b) transmission line characteristic estimating means for modeling an impulse response between a transmitter and a receiver by comparing only the synchronizing signal data portion detected by said synchronizing signal data detecting means with a reference signal; (c) decoding means for decoding the reception signal data series by using a Viterbi algorithm on the basis of the modeled impulse response obtained from said transmission line characteristic estimating means; and (d) a normalization circuit means for avoiding an overflow which takes place when a path metric is calculated in an error correction process utilizing the Viterbi algorithm.
Claim 3
Dependent Claim
44 words
The Viterbi equalizer according to claim 1 wherein said transmission line characteristic estimating means employs a method of least squares when the modelled impulse response between the transmitter and the receiver is obtained by comparing said synchronizing signal data portions with said reference signal.
Claim 4
Dependent Claim
37 words
The Viterbi equalizer according to claim 1 wherein said transmission line characteristic estimating means estimates a transmission line characteristic by correlating a synchronizing signal actually received with a known synchronizing signal pattern within a receiver in advance.
Claim 5
Dependent Claim
35 words
The Viterbi equalizer according to claim 1 wherein said decoding means calculates a branch metric of said Viterbi algorithm on the basis of said modelled impulse response obtained from said transmission line characteristic estimating means.
Claim 6
Dependent Claim
49 words
The Viterbi equalizer according to claim 1 wherein said decoding means calculates a branch metric of said Viterbi algorithm on the basis of said modelled impulse response obtained from said transmission line characteristic estimating means, and said decoding means calculating a path metric by using said calculated branch metric.
References Cited (Backward Citations)
US5091918A
Cited
US5204878A
Cited
US5349607A
Cited
EP0496152A2
Cited
EP0529585A2
Cited
US5285480A
Cited
EP0551803A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-12-03 | 2000-06-03 | 2000-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-03 | 2004-06-03 | 2004-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-03 | 2008-06-03 | 2008-12-03 | $7700.00 | Window Closed / Lapsed |