US4715037A
Expired / Lapsed
US
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Viterbi decoder comprising a majority circuit in producing a decoded signal
Assignee: NEC Corp
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Filing: 1985-02-25
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Granted: 1987-12-22
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Expires: 2005-02-25
Abstract
Abstract In a Viterbi decoder for use in producing a decoded signal by correcting and decoding convolutional codes, a majority circuit (46) is connected to a path memory (45). At each of the time slots used for the respective convolutional codes, the majority circuit makes a decision and selects a decoded datum of the decoded signal in response to a majority of information bits which are memorized in the path memory. The Viterbi decoder consists of a read-only memory, which simplifies the circuit, reduces the required number of circuit elements, and makes a lower cost circuit.
Inventors
- 👤 Toshiharu Yagi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:34
CPC Classifications
H; H03; H03M; H03M13/00; H03M13/37; H03M13/39; H03M13/41
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
139 words
A Viterbi decoder for use in producing a decoded signal by correcting and decoding convolutional codes in synchronism with a succession of time slots, said Viterbi decoder including a path memory for memorizing, at each of said time slots, survivor paths in terms of information bits associated with the respective survivor paths of a predetermined number of time slots, and a majority circuit consisting of a read-only memory for deciding a decoded datum of said decoded signal for each of the time slots to provide a predetermined one of said information bits 0 and 1 in response to a majority of said information bits and to provide a predetermined one of said information bits 0 and 1 in response to a tie situation where the number of said information bits 0 equals the number of said information bits "1".
Claim 2
Dependent Claim
139 words
A Viterbi decoder for use in producing a decoded signal by correcting and decoding convolutional codes in synchronism with a succession of time slots, said Viterbi decoder including a path memory for memorizing, at each of said time slots, survivor paths in terms of information bits associated with the respective survivor paths of a predetermined number of time slots, and a majority circuit consisting of a read-only memory for deciding a decoded datum of said decoded signal for each of the time slots to provide a predetermined one of said information bits 0 and 1 in response to a majority of said information bits and to provide a predetermined one of said information bits 0 and 1 in response to a tie situation where the number of said information bits 0 equals the number of said information bits "1".
Claim 3
Dependent Claim
31 words
A Viterbi decoder as claimed in claim 1, wherein said predetermined number of the time slots is equal to at least six times a predetermined code length of said convolutional codes.
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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) | 1990-12-21 | 1991-06-22 | 1991-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-21 | 1995-06-22 | 1995-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-21 | 1999-06-22 | 1999-12-22 | $7700.00 | Window Closed / Lapsed |