Partial packet recovery in wireless networks

Patent metadata

Field	Value
Publication number	US-9203441-B2
Application number	US-201213483659-A
Country	US
Kind code	B2
Filing date	May 30, 2012
Priority date	May 30, 2012
Publication date	Dec 1, 2015
Grant date	Dec 1, 2015

Abstract

Systems and methods for improved packet throughput using partial packets are provided in which data recovery of partial packets of a plurality of received coded packets is performed across the plurality of received coded packets. The plurality of received coded packets, including the received partial packets, can be buffered in a memory and used in recovering the data for the partial packets. As soon as the total number of received packets (including valid and partial) becomes greater than the generation size, a decoding process can be attempted utilizing the partial packets as part of the redundancy used for data recovery. During the decoding process, the received packets are evaluated across packets instead of on a per-packet basis.

First claim

We claim:

1. A method for data recovery in a wireless network, the method comprising:
receiving a plurality of coded packets; and
performing data recovery of partial packets of the plurality of coded packets across the plurality of coded packets, the partial packets of the plurality of coded packets each containing at least one erroneous bit, the plurality of coded packets including the partial packets being buffered in a memory and at least one of the partial packets of the plurality of coded packets being used in performing the data recovery.

2. The method of claim 1 , wherein performing the data recovery comprises:
detecting corrupted information in the partial packets by performing a consistency check for validity of symbols across the plurality of coded packets.

3. The method according to claim 2 , wherein performing the consistency check comprises:
decoding any set of symbols, the set of symbols containing symbols from at least two coded packets of the plurality of coded packets and a total number of symbols of the set of symbols being at least a generation size;
using coefficients associated with a remaining coded packet or packets not having a symbol contained in the decoded set of symbols to obtain a regenerated coded symbol of the remaining coded packet or packets; and
comparing the regenerated coded symbol with a coded symbol of the remaining coded packet or packets to obtain a consistency check result.

4. A wireless network node comprising:
an antenna;
a processor;
a memory; and
a data recovery module having instructions that when executed by the processor cause the wireless network node to perform data recovery of partial packets of a plurality of coded packets, the partial packets of the plurality of coded packets each containing at least one erroneous bit, the plurality of coded packets being received via the antenna and buffered in the memory for performing the data recovery across the plurality of coded packets, at least one of the partial packets of the plurality of coded packets being used in performing the data recovery.

5. The wireless network node of claim 4 , wherein the data recovery module is executed at a data link layer of the wireless network node.

6. The wireless network node of claim 4 , wherein the data recovery module has instructions, that when executed by the processor, cause the wireless network node to:
perform an error detection check of each coded packet of the plurality of coded packets received via the antenna to determine an error check result, the error check result indicating a valid packet or a partial packet; and store the coded packet and the error check result in the memory; and
perform the data recovery when the number of coded packets received and stored in memory is greater than a generation size (g), the data recovery comprising:
performing a consistency check for a symbol-column of the coded packets stored in the memory, a symbol-column being a same position portion of each of the coded packets; and
decoding the symbol-column of the coded packets after obtaining a success from performing the consistency check.

7. The wireless network node of claim 6 , wherein the consistency check is performed column-by-column, the column-by-column check progressing in a direction from a first position portion to an end position portion.

8. The wireless network node of claim 6 , performing the consistency check for the column comprises:
obtaining a decoded portion for each of the generation size g number of the coded packets stored in the memory by performing:

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where i n indicates a particular coded packet of the coded packets for n=1 to a total of g packets of the coded packets, j is the position of the portion, D is the decoded portion, C is the coefficients of the coded packet, and P is the portion of the coded packet;
obtaining a regenerated coded portion for each remaining coded packet of the coded packets stored in the memory by performing:

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Assignees

• Angelopoulos Georgios
• Medard Muriel
• Chandrakasan Anantha P
• Massachusetts Inst Technology

Inventors

• Angelopoulos Georgios
• Medard Muriel
• Chandrakasan Anantha P

Classifications

• H03M13/6306

  Error control coding in combination with Automatic Repeat reQuest [ARQ] and diversity transmission, e.g. coding schemes for the multiple transmission of the same information or the transmission of incremental redundancy (H03M13/3761, H03M13/3769 and H03M13/635 take precedence) · CPC title

• H03M13/3761

  using code combining, i.e. using combining of codeword portions which may have been transmitted separately, e.g. Digital Fountain codes, Raptor codes or Luby Transform [LT] codes · CPC title

• H03M13/09

  Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit · CPC title

• H03M13/373 Primary

  with erasure correction and erasure determination, e.g. for packet loss recovery or setting of erasures for the decoding of Reed-Solomon codes · CPC title

• H03M13/3746

  with iterative decoding · CPC title