US5838697A
Expired / Lapsed
US
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Bit error counting method and counting technical field
Assignee: Canon Inc
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Filing: 1997-04-29
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Granted: 1998-11-17
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Expires: 2017-04-29
Abstract
Abstract An error detecting device and method for use when applying the Viterbi decoding to an inputted signal, when it is necessary to derive the number of errors included in a decoded signal. A value of a path metric derived upon the Viterbi decoding is read out and outputted as the number of errors. Two kinds of decoding devices, each reading out a value of a path metric and outputting this value as the number of errors, are provided for a sound signal and an FACCH signal. A signal is inputted to both devices for decoding, respectively. The numbers of errors derived from both devices are compared, and it is judged based on a result of the comparison, whether the inputted signal is the sound signal or the FACCH signal.
Inventors
- 👤 Masami Abe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:12
CPC Classifications
H; H03; H03M; H03M13/00; H03M13/65; H03M13/6502; H03M13/37; H03M13/39; H03M13/41; H03M13/4107
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
198 words
A signal identification device for identifying a received signal, the device comprising: a first decoding circuit for Viterbi decoding a signal of a first type, the first decoding circuit having a first calculation circuit for repeatedly calculating branch metrics of the received signal based on a first generator polynomial, and a first ACS circuit for selecting a first survivor path of first maximum-likelihood survivor path metrics which reflect the branch metrics calculated by the first calculation circuit; a second decoding circuit for Viterbi decoding a signal of a second type, the second decoding circuit having a second calculation circuit for repeatedly calculating branch metrics of the received signal based on a second generator polynomial, and a second ACS circuit for selecting a second survivor path of second maximum-likelihood survivor path metrics which reflect the branch metrics calculated by the second calculation circuit; and a signal-identifying circuit for identifying the received signal as a signal of the first type or a signal of the second type, based on the selected first survivor path of the last of the first maximum-likelihood survivor path metrics and the selected second survivor path of the last of the second maximum-likelihood survivor path metrics.
Claim 2
Dependent Claim
198 words
A signal identification device for identifying a received signal, the device comprising: a first decoding circuit for Viterbi decoding a signal of a first type, the first decoding circuit having a first calculation circuit for repeatedly calculating branch metrics of the received signal based on a first generator polynomial, and a first ACS circuit for selecting a first survivor path of first maximum-likelihood survivor path metrics which reflect the branch metrics calculated by the first calculation circuit; a second decoding circuit for Viterbi decoding a signal of a second type, the second decoding circuit having a second calculation circuit for repeatedly calculating branch metrics of the received signal based on a second generator polynomial, and a second ACS circuit for selecting a second survivor path of second maximum-likelihood survivor path metrics which reflect the branch metrics calculated by the second calculation circuit; and a signal-identifying circuit for identifying the received signal as a signal of the first type or a signal of the second type, based on the selected first survivor path of the last of the first maximum-likelihood survivor path metrics and the selected second survivor path of the last of the second maximum-likelihood survivor path metrics.
Claim 3
Dependent Claim
18 words
A device according to claim 1, wherein the first and second generator polynomials are different from each other.
Claim 4
Dependent Claim
170 words
A device according to claim 1, wherein the signal-identifying circuit compares a first survivor path of the last of the first maximum-likelihood survivor path metrics selected by the first ACS circuit, to a first preset value, and if the first survivor path of the last of the first maximum-likelihood survivor path metrics selected by the first ACS circuit is smaller than the first preset value, the signal-identifying circuit identifies the received signal as being of the first type, and wherein, if the last of the first maximum-likelihood survivor path metrics selected is not smaller than the first preset value, then the signal identifying circuit compares a second survivor path of the second maximum-likelihood survivor path metrics selected by the second ACS circuit, to a second preset value, and if the second survivor path of the last of the second maximum-likelihood survivor path metrics selected by the second ACS circuit is smaller than the second preset value, the signal identifying circuit identifies the received signal as being of the second type.
Claim 5
Dependent Claim
18 words
A device according to claim 3, wherein the first and second generator polynomials are different from each other.
Claim 6
Independent Claim
161 words
A method of identifying a received signal, comprising: repeatedly calculating first branch metrics of the received signal based on a first generator polynomial; determining first maximum-likelihood survivor path metrics which reflect the calculated first branch metrics; selecting a first survivor path of the determined first maximum-likelihood survivor path metrics; setting the first survivor path of a last one of the determined first maximum-likelihood survivor path metrics as a first error number; repeatedly calculating second branch metrics of the received signal based on a second generator polynomial; determining second maximum-likelihood survivor path metrics which reflect the calculated second branch metrics; selecting a second survivor path of the determined second maximum-likelihood survivor path metrics; setting the second survivor path of a last one of the determined second maximum-likelihood survivor path metrics as a second error number; and identifying the received signal as a signal of a first type or a signal of a second type, based on the first and second error numbers.
Claim 7
Independent Claim
161 words
A method of identifying a received signal, comprising: repeatedly calculating first branch metrics of the received signal based on a first generator polynomial; determining first maximum-likelihood survivor path metrics which reflect the calculated first branch metrics; selecting a first survivor path of the determined first maximum-likelihood survivor path metrics; setting the first survivor path of a last one of the determined first maximum-likelihood survivor path metrics as a first error number; repeatedly calculating second branch metrics of the received signal based on a second generator polynomial; determining second maximum-likelihood survivor path metrics which reflect the calculated second branch metrics; selecting a second survivor path of the determined second maximum-likelihood survivor path metrics; setting the second survivor path of a last one of the determined second maximum-likelihood survivor path metrics as a second error number; and identifying the received signal as a signal of a first type or a signal of a second type, based on the first and second error numbers.
Claim 8
Dependent Claim
18 words
A method according to claim 5, wherein the first and second generator polynomials are different from each other.
Claim 9
Dependent Claim
97 words
A method according to claim 5, wherein said identifying the received signal includes comparing the first error number to a first preset value, and if the first error number is smaller than the first preset value, then identifying the received signal as being of the first type, and wherein, if the first error number is not smaller than the first preset value, then comparing the second error number to a second preset value, and if the second error number is smaller than the second preset value, then identifying the received signal as being of the second type.
Claim 10
Dependent Claim
18 words
A method according to claim 7, wherein the first and second generator polynomials are different from each other.
Claim 11
Independent Claim
223 words
A method of identifying a received signal, comprising: performing a first Viterbi decoding process, including performing a first calculation process, including calculating first branch metrics of the received signal, based on a first generator polynomial corresponding to a first type of signal, and performing a first metrics selection process, including successively selecting a first survivor path of first maximum-likelihood survivor path metrics which reflect the calculated first branch metrics; performing a second Viterbi decoding process, including performing a second calculation process, including calculating second branch metrics of the received signal, based on a second generator polynomial corresponding to a second type of signal, and performing a second metrics selection process, including successively selecting a second survivor path of second maximum-likelihood survivor path metrics which reflect the calculated second branch metrics; comparing the first survivor path selected during intermediate portions of the first metrics selection processes, to a first preset value; comparing the second survivor path selected during intermediate portions of the second metrics selection process to a second preset value; terminating the first decoding process and identifying the received signal as being of the second type, if the second survivor path exceeds the second preset value; and terminating the second decoding process and identifying the received signal as being of the first type, if the first survivor path exceeds the first preset value.
Claim 12
Independent Claim
223 words
A method of identifying a received signal, comprising: performing a first Viterbi decoding process, including performing a first calculation process, including calculating first branch metrics of the received signal, based on a first generator polynomial corresponding to a first type of signal, and performing a first metrics selection process, including successively selecting a first survivor path of first maximum-likelihood survivor path metrics which reflect the calculated first branch metrics; performing a second Viterbi decoding process, including performing a second calculation process, including calculating second branch metrics of the received signal, based on a second generator polynomial corresponding to a second type of signal, and performing a second metrics selection process, including successively selecting a second survivor path of second maximum-likelihood survivor path metrics which reflect the calculated second branch metrics; comparing the first survivor path selected during intermediate portions of the first metrics selection processes, to a first preset value; comparing the second survivor path selected during intermediate portions of the second metrics selection process to a second preset value; terminating the first decoding process and identifying the received signal as being of the second type, if the second survivor path exceeds the second preset value; and terminating the second decoding process and identifying the received signal as being of the first type, if the first survivor path exceeds the first preset value.
Claim 13
Dependent Claim
18 words
A method according to claim 9, wherein the first and second generator polynomials are different from each other.
Claim 14
Dependent Claim
242 words
A signal identification device for identifying a received signal, the device comprising: a first decoding circuit for Viterbi decoding a signal of a first type, the first decoding circuit having a first calculation circuit for repeatedly calculating branch metrics of the received signal based on a first generator polynomial, and a first ACS circuit for selecting a first survivor path of first maximum-likelihood path metrics which reflect the branch metrics calculated by the first calculation circuit; a second decoding circuit for Viterbi decoding a signal of a second type, the second decoding circuit having a second calculation circuit for repeatedly calculating branch metrics of the received signal based on a second generator polynomial, and a second ACS circuit for selecting a second survivor path of second maximum-likelihood survivor path metrics which reflect the branch metrics calculated by the second calculation circuit; and a signal-identifying circuit for identifying the received signal as a signal of the first type or a signal of the second type, and if during an intermediate portion of the decoding by the first decoding circuit the first survivor path exceeds a first preset value, then the signal-identifying circuit identifies the received signal as being the signal of the second type, and if during the intermediate portion of the decoding by the second decoding circuit the second survivor path exceeds a second preset value, then the signal-identifying circuit identifies the received signal as being the signal of the first type.
Claim 15
Dependent Claim
242 words
A signal identification device for identifying a received signal, the device comprising: a first decoding circuit for Viterbi decoding a signal of a first type, the first decoding circuit having a first calculation circuit for repeatedly calculating branch metrics of the received signal based on a first generator polynomial, and a first ACS circuit for selecting a first survivor path of first maximum-likelihood path metrics which reflect the branch metrics calculated by the first calculation circuit; a second decoding circuit for Viterbi decoding a signal of a second type, the second decoding circuit having a second calculation circuit for repeatedly calculating branch metrics of the received signal based on a second generator polynomial, and a second ACS circuit for selecting a second survivor path of second maximum-likelihood survivor path metrics which reflect the branch metrics calculated by the second calculation circuit; and a signal-identifying circuit for identifying the received signal as a signal of the first type or a signal of the second type, and if during an intermediate portion of the decoding by the first decoding circuit the first survivor path exceeds a first preset value, then the signal-identifying circuit identifies the received signal as being the signal of the second type, and if during the intermediate portion of the decoding by the second decoding circuit the second survivor path exceeds a second preset value, then the signal-identifying circuit identifies the received signal as being the signal of the first type.
Claim 16
Dependent Claim
32 words
A signal identification device according to claim 11, wherein the signal-identifying circuit terminates decoding the received signal in the first decoding circuit if the first survivor path exceeds the first preset value.
Claim 17
Dependent Claim
32 words
A signal identification device according to claim 11, wherein the signal-identifying circuit terminates decoding the received signal in the second decoding circuit if the second survivor path exceeds the second preset value.
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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) | 2001-11-16 | 2002-05-18 | 2002-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-16 | 2006-05-18 | 2006-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-16 | 2010-05-18 | 2010-11-17 | $7700.00 | Window Closed / Lapsed |