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US5745502A Expired / Lapsed US ⏱️ 0.0 years remaining

Error detection scheme for ARQ systems

Assignee: Ericsson Inc
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Filing: 1996-09-27
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Granted: 1998-04-28
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Expires: 2016-09-27
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Abstract

Abstract A method of error correction for an ARQ system allows decoding when an even number of flawed packets are received. Multiple flawed replications of a transmitted bit sequence are compared bit-by-bit. A set of composite packets is formed containing all possible combinations of values at the disputed bit positions. A validity check is performed on each of the composite packets. If only a single composite packet passes the validity check, an acknowledgment signal is sent.

Inventors

  • 👤 Ali S. Khayrallah
  • 👤 David R. Irvin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 17:58
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/08; G06F11/10; H; H03; H03M; H03M13/00; H03M13/03; H03M13/05; H03M13/09; H03M13/093; G11; G11B; G11B20/00; G11B20/10; G11B20/18; G11B20/1803; H04; H04L; H04L1/00; H04L1/12; H04L1/16; H04L1/1607; H04L1/1628; H04L1/18; H04L1/1812; H04L1/1829; H04L1/1835; H04L1/1838; H04L1/1845; H04L1/1867; H04L1/188; H04L1/0001; H04L1/1806; H04L1/1809; H04L1/1874; H04L1/1877; H04L2001/0092; H04L2001/0093

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 125 words
A method for correcting errors in a plurality of flawed replications of a transmitted packet which includes a variable information field and a fixed information field said method comprising: a) changing the variable information field in at least one of said flawed replications to make the variable information fields in all replications equal; b) recalculating the redundancy fields in the altered replications to subtract the redundancy vectors attributable to the changes in the variable information field; c) comparing said altered replications to determine the disputed bit positions; d) generating at least one composite packet based on a comparison of the multiple iterations of the flawed replication, wherein said multiple iterations include at least one altered replication; and e) determining the validity of said composite packet(s).
Claim 2
Independent Claim 125 words
A method for correcting errors in a plurality of flawed replications of a transmitted packet which includes a variable information field and a fixed information field said method comprising: a) changing the variable information field in at least one of said flawed replications to make the variable information fields in all replications equal; b) recalculating the redundancy fields in the altered replications to subtract the redundancy vectors attributable to the changes in the variable information field; c) comparing said altered replications to determine the disputed bit positions; d) generating at least one composite packet based on a comparison of the multiple iterations of the flawed replication, wherein said multiple iterations include at least one altered replication; and e) determining the validity of said composite packet(s).
Claim 3
Dependent Claim 20 words
The method according to claim 1 wherein the composite packet is generated by majority-logic vote at the disputed bit position.
Claim 4
Dependent Claim 44 words
The method according to claim 1 wherein the composite packet is generated by a substitution technique in which a plurality of composite packets are generated by substituting all possible combinations of values at the disputed bit positions into a string contained the undisputed bits.
Claim 5
Independent Claim 106 words
A method for correcting errors in a plurality of flawed replications of a transmitted packet which includes a variable information field and a fixed information field said method comprising: a) selecting one replication as a reference; b) changing the variable information field in the remaining replications to make the variable information fields in all replications equal; c) recalculating the redundancy fields in the altered replications to subtract the redundancy vector attributable to the changes in the variable information field; d) comparing said replications to determine the disputed bit positions; e) determining the validity of said composite packet(s); and f) determining the validity of said composite packets.
Claim 6
Independent Claim 106 words
A method for correcting errors in a plurality of flawed replications of a transmitted packet which includes a variable information field and a fixed information field said method comprising: a) selecting one replication as a reference; b) changing the variable information field in the remaining replications to make the variable information fields in all replications equal; c) recalculating the redundancy fields in the altered replications to subtract the redundancy vector attributable to the changes in the variable information field; d) comparing said replications to determine the disputed bit positions; e) determining the validity of said composite packet(s); and f) determining the validity of said composite packets.
Claim 7
Dependent Claim 20 words
The method according to claim 4 wherein the composite packet is generated by majority-logic vote at the disputed bit position.
Claim 8
Dependent Claim 44 words
The method according to claim 4 wherein the composite packet is generated by a substitution technique in which a plurality of composite packets are generated by substituting all possible combinations of values at the disputed bit positions into a string contained the undisputed bits.
Claim 9
Independent Claim 113 words
A method for correcting errors in a plurality of flawed replications of a transmitted packet which includes a variable information field and a fixed information field said method comprising: a) changing the variable information field in each replication to a predetermined value; b) recalculating the redundancy fields in each replication to subtract the redundancy vector attributable to the changes in the variable information field; c) comparing said altered replications to determine the disputed bit positions; d) generating at least one composite packet based on a comparison of the multiple iterations of the flawed replication, wherein said multiple iterations include at least one altered replication; and e) determining the validity of said composite packet(s).
Claim 10
Independent Claim 113 words
A method for correcting errors in a plurality of flawed replications of a transmitted packet which includes a variable information field and a fixed information field said method comprising: a) changing the variable information field in each replication to a predetermined value; b) recalculating the redundancy fields in each replication to subtract the redundancy vector attributable to the changes in the variable information field; c) comparing said altered replications to determine the disputed bit positions; d) generating at least one composite packet based on a comparison of the multiple iterations of the flawed replication, wherein said multiple iterations include at least one altered replication; and e) determining the validity of said composite packet(s).
Claim 11
Dependent Claim 20 words
The method according to claim 7 wherein the composite packet is generated by majority-logic vote at the disputed bit position.
Claim 12
Dependent Claim 44 words
The method according to claim 7 wherein the composite packet is generated by a substitution technique in which a plurality of composite packets are generated by substituting all possible combinations of values at the disputed bit positions into a string contained the undisputed bits.
Claim 13
Independent Claim 68 words
A method for altering a received codeword having a variable information field, a fixed information field, and a redundancy field to allow comparison with another received codeword having the same fixed information field comprising: a) changing the variable information field in the received codeword; and b) recalculating the redundancy field in the received codeword to eliminate the redundancy vector attributable to the changes in the variable information field.
Claim 14
Independent Claim 68 words
A method for altering a received codeword having a variable information field, a fixed information field, and a redundancy field to allow comparison with another received codeword having the same fixed information field comprising: a) changing the variable information field in the received codeword; and b) recalculating the redundancy field in the received codeword to eliminate the redundancy vector attributable to the changes in the variable information field.
Claim 15
Dependent Claim 27 words
The method according to claim 10 wherein the variable information field is altered to make it equal to the variable information field in the other received codeword.
Claim 16
Dependent Claim 21 words
The method according to claim 10 wherein the variable information field is altered to make it equal to a predetermined value.
Claim 17
Dependent Claim 94 words
An error correcting method for correcting errors in a diversity receiver where multiple copies of the transmitted data packet are received, said error correcting method comprising the steps of: a) comparing the multiple copies of said received data packet to determine the disputed bit positions; b) creating a set of composite packets by substituting all possible combinations of values at the disputed bit positions into a string containing the undisputed bit positions; c) determining the validity of each composite packet; and d) if only one composite packet is valid, outputting the valid composite packet.
Claim 18
Dependent Claim 94 words
An error correcting method for correcting errors in a diversity receiver where multiple copies of the transmitted data packet are received, said error correcting method comprising the steps of: a) comparing the multiple copies of said received data packet to determine the disputed bit positions; b) creating a set of composite packets by substituting all possible combinations of values at the disputed bit positions into a string containing the undisputed bit positions; c) determining the validity of each composite packet; and d) if only one composite packet is valid, outputting the valid composite packet.
Claim 19
Dependent Claim 28 words
The error correcting method of claim 13 further including the step of comparing the number of disputed bit positions with a predetermined threshold before creating the composite packets.
Claim 20
Dependent Claim 27 words
The error correcting method of claim 14 wherein the composite packets are created only when the number of disputed bit positions is less than said predetermined threshold.
Claim 21
Dependent Claim 18 words
The error correcting method according to claim 14 wherein said predetermined threshold is a function of battery capacity.
Claim 22
Dependent Claim 20 words
The error correcting method according to claim 14 wherein said predetermined threshold is a function of available processor instruction cycles.

References Cited (Backward Citations)

US5241548A Cited
US5497382A Cited
US5577053A Cited
US5687188A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-04-27 2001-10-27 2002-04-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-04-27 2005-10-27 2006-04-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-04-27 2009-10-27 2010-04-28 $7700.00 Window Closed / Lapsed

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