Outer coding framework

• US 8,732,542 B2
• Filed: 07/09/2013
• Issued: 05/20/2014
• Est. Priority Date: 12/11/2007
• Status: Expired due to Fees

• Current Assignee: Monument Bank of Intellectual Property, LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: Quarterhill Inc. (f/k/a Wi-LAN Inc.)
• Inventors: Nebat, Yoav, Zahedi, Sina
• Primary Examiner(s): Iqbal, Nadeem
• Application Number:
  US13/938,033
• Publication Number:
  US 20140019832A1
• Time in Patent Office: 315 Days
• Field of Search: 714745-753, 714758-762, 714/765, 714/774, 714784-790
• US Class Current: 714/748
• CPC Class Codes: H03M 13/09 Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit
• CPC Class Codes: H04L 1/0084 Formats for payload data
• CPC Class Codes: H04W 72/30 Resource management for broadcast services

Abstract

The subject matter disclosed herein provides an outer coding framework for minimizing the error rate of packets. In one aspect, the method may include determining, based on a cyclic redundancy check, a first erasure table including zero or more erasures; determining a second erasure table; using the first erasure table to locate errors in a frame of packets, when the zero or more erasures of the first erasure table do not exceed a threshold of erasures; and using the second erasure table to locate errors in the frame of packets, when the one or more erasures of the first erasure table do exceed the threshold of erasures. The frame may include the one or more rows encoded using the outer code. The block that is read may be provided to enable an inner code to encode the block before transmission. Related systems, apparatus, methods, and/or articles are also described.

Claims

1. A subscriber station comprising:

a memory storage; and

a processor configured to execute instructions stored in the memory storage for performing the steps of;

determining, based on a cyclic redundancy check, a first erasure table including zero or more erasures;

determining a second erasure table, wherein the first and second erasure tables are associated with the same data;

using the first erasure table to locate errors in a frame of packets, when the zero or more erasures of the first erasure table do not exceed a threshold of erasures; and

using the second erasure table to locate errors in the frame of packets, when the zero or more erasures of the first erasure table do exceed the threshold of erasures.

2. The subscriber station of claim 1, wherein the step of determining the second erasure table uses at least one of a receive failure and a signal-to-noise ratio, wherein the frame comprises a Reed-Solomon table.

3. The subscriber station of claim 1, wherein the processor is further configured to execute instructions stored in the memory storage for performing the steps of:

counting erasures in at least one codeword in at least one of the first erasure table and the second erasure table; and

decoding the frame of packets, when additional information is included in at least one of the first erasure table and the second erasure table.

4. The subscriber station of claim 1, wherein the processor is further configured to execute instructions stored in the memory storage for performing the steps of:

not using the second erasure table to locate errors in a codeword in the frame of packets when the second erasure table comprises a plurality of erasures in the codeword exceeding a second threshold; and

decoding the codeword in the frame of packets without using erasure information when the threshold and the second threshold are exceeded.

5. The subscriber station of claim 1, wherein the processor is further configured to execute instructions stored in the memory storage for performing the steps of:

decoding at least one codeword in the frame of packets using the second erasure table to provide a decoded codeword;

determining whether the decoded codeword is in error; and

decoding the codeword in the frame of packets without using erasure information based on the deframer determining whether the decoded codeword is in error.

6. The subscriber station of claim 1, wherein the processor is further configured to execute instructions stored in the memory storage for performing the steps of:

receiving packets appended with a cyclic redundancy check, wherein the cyclic redundancy check is used to determine erasures for the first erasure table;

inserting the received packets into one or more columns of the frame;

decoding, using an outer code, one or more rows of the frame; and

reading a portion of the frame, when the one or more rows are decoded using the outer code, wherein the portion is inserted into an application data table.

7. A subscriber station comprising:

a memory storage; and

a processor configured to execute instructions stored in the memory storage for performing the steps of;

receiving application data packets, wherein each of the application data packets is appended with a cyclic redundancy check and wherein the application data packets are included in a frame and decoded using an outer code;

reading, from the frame, at least one application data packet; and

discarding at least one of the read application data packets, when the cyclic redundancy check appended to the at least one read application data packet indicates an error.

8. The subscriber station of claim 7, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of inserting link-layer packets into the frame, the frame configured as a Reed-Solomon table, wherein the link-layer packets are received without an appended cyclic redundancy check (CRC).

9. The subscriber station of claim 7, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of discarding the at least one of the read application data packets by not providing the application data packet in error to another component of the subscriber station.

10. The subscriber station of claim 7, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of discarding the at least one of the read application data packets by using at least one of the read application data packets, when the cyclic redundancy check appended to the at least one read application data packet indicates that the at least one read application data packet is not in error.

11. A subscriber station comprising:

a memory storage; and

a processor configured to execute instructions stored in the memory storage for performing the steps of;

inserting link-layer packets into a frame, the frame configured to include a data portion and a parity portion, wherein the parity portion is configured to substantially maintain a quantity of frame errors;

decoding, using an outer code, the frame, when one or more columns of the frame have been filled; and

reading, from the frame, a plurality of application data packets.

12. The subscriber station of claim 11, wherein the frame error is an error in a codeword of the frame, and wherein the frame is configured to have a fixed quantity of columns.

13. The subscriber station of claim 11, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of maintaining the quantity of frame errors by varying, in another frame, a fraction of columns of the corresponding parity portion.

14. The subscriber station of claim 11, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of maintaining the quantity of frame errors by increasing, in another frame, a fraction of columns of the corresponding parity portion.

15. The subscriber station of claim 11, wherein the frame is in a first time interval and the other frame is in a second time interval.

16. A subscriber station comprising:

a memory storage; and

a processor configured to execute instructions stored in the memory storage for performing the steps of;

receiving link-layer packets, wherein a first portion of the received link-layer packets is appended with a cyclic redundancy check and a second portion of the received link-layer packets is not appended with a cyclic redundancy check;

inserting the received link-layer packets into one or more columns of one or more frames, the first portion of the received link-layer packets having the appended cyclic redundancy check removed before insertion into the frame;

decoding, using an outer code, one or more rows of the one or more frames; and

reading the one or more rows of the frame, when the one or more rows are decoded using the outer code, wherein the one or more rows of the one or more frames forms an application data packet.

17. The subscriber station of claim 16, wherein the processor is further configured to execute instructions stored in the memory storage for performing the steps of:

receiving the first portion of packets as a first substream of packets; and

receiving the second portion of packets as a second substream of packets, the first substream of packets having a higher priority than the second substream of packets.

18. The subscriber station of claim 16, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of inserting the received link-layer packets into the one or more frames each configured as a Reed-Solomon table.

19. The subscriber station of claim 16, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of decoding the received link-layer packets using an inner code.

20. The subscriber station of claim 16, wherein the processor is further configured to execute instructions stored in the memory storage for performing the step of receiving, as the first portion of the received link-layer packets appended with the cyclic redundancy check, hybrid automatic retransmission request (HARQ) protocol data units.

21. A subscriber station comprising:

a memory storage; and

a processor configured to execute instructions stored in the memory storage for performing the steps of;

determining, based on a cyclic redundancy check, a first erasure table including zero or more erasures;

determining a second erasure table;

using the first erasure table to locate errors in a frame of packets, when the zero or more erasures of the first erasure table do not exceed a threshold of erasures;

using the second erasure table to locate errors in the frame of packets, when the zero or more erasures of the first erasure table do exceed the threshold of erasures, wherein the second erasure table is not used to locate errors in a codeword in the frame of packets when the second erasure table comprises a plurality of erasures in the codeword exceeding a second threshold; and

decoding the codeword in the frame of packets without using erasure information when the threshold and the second threshold are exceeded.