EFFICIENT ERROR CORRECTION SCHEME FOR DATA TRANSMISSION IN A WIRELESS IN-BAND SIGNALING SYSTEM

• US 20110029832A1
• Filed: 07/13/2010
• Published: 02/03/2011
• Est. Priority Date: 08/03/2009
• Status: Active Grant

• Current Assignee: Karma Automotive LLC (Wanxiang Group Corporation)
• Original Assignee: Airbiquity Incorporated
• Inventors: Birmingham, Kiley, Hong, Leon L.
• Granted Patent: US 8,418,039 B2
• Time in Patent Office: Days
• US Class Current: 714/748
• CPC Class Codes: H04L 1/0084 Formats for payload data
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 1/20 using signal quality detector

Abstract

In one example, a mobile device segments a payload for transmission to a remote server and provides redundant data for each payload segment. The remote server examines the received payload on a per segment basis using the redundant data to identify segments associated with errors. The server then requests error correction bits for the identified segments using one or more exchanges with the mobile device. Thereafter, the server can perform error correction using the received error correction bits and then request re-transmission of the payload, if needed.

Claims

1. A processor readable medium encoded with instructions that, if executed, result in:

receiving and demodulating audio tones into a packet having a header and a payload, wherein the payload includes a plurality of segments each having error correction bits corresponding thereto;

performing bit correction on the segments using their corresponding error correction bits and identifying ones of the segments that are associated with errors according to the bit correction;

generating and sending a request for additional error correction bits for the identified ones of the segments;

receiving and demodulating subsequently received audio tones into the requested additional error correction bits; and

correcting the payload of the packet using the subsequently received error correction bits.

2. The processor readable medium of claim 1, wherein the instructions, if executed, result in:

performing bit correction on the identified ones of the segments using their corresponding additional error correction bits to identify any such segments that correspond with an increase in associated errors; and

generating and sending a request for yet further error correction bits for the identified segments having the increase in associated errors.

3. The processor readable medium of claim 2, wherein the instructions, if executed, result

repeating segment correction using the most recently received error correction bits as well as the generating and sending in response thereto until a current correction indicates no new errors with respect to a previous correction;

and

examining a result of the repetition using error detection bits received with the packet to determine whether there are uncorrected errors remaining.

4. The processor readable medium of claim 1, wherein the instructions, if executed, result in:

when errors are discovered, deferring any requests for re-transmission of the content to which the error correction bits correspond until receiving responses to a series of requests for additional error correction bits.

5. The processor readable medium of claim 4, wherein the series of received responses provide gradually increasing amounts of error correction information for a particular one of the segments.

6. The processor readable medium of claim 1, wherein the error correction bits comprise Forward Error Correction (FEC) information.

7. The processor readable medium of claim 6, wherein the instructions, if executed, result in:

examining the corrected payload using error detection bits included with the received and demodulated packet to determine whether there are uncorrected errors remaining; and

requesting re-transmission of the payload if the examination using the error detection bits indicates uncorrected errors remaining.

8. The processor readable medium of claim 7, wherein the error detection bits comprise Cyclic Redundancy Check (CRC) information.

9. A processor readable medium encoded with instructions that, if executed, result in:

generating redundant data corresponding to each segment of a segmented packet payload;

modulating a packet containing the segment data and the generated redundant data using an In-Band Signaling (IBS) modem and transmitting signals resulting therefrom over a voice band of a wireless telecommunications network;

receiving back a response requesting error correction bits for an identified segment; and

modulating the error correction bits for the segment identified in the request and transmitting signals resulting therefrom over the voice band of the wireless telecommunications network.

10. The processor readable medium of claim 9 encoded with instructions that, if executed, result in:

after transmitting the signals resulting from the modulation of the error correction bits, receiving back another response requesting additional error correction bits for a subsequently identified segment; and

modulating the additional error correction bits for the subsequently identified segment and transmitting signals resulting therefrom over the voice band of the wireless telecommunications network.

11. The processor readable medium of claim 10, wherein the additional error correction bits corresponding to the segment comprise more information than the error correction bits corresponding to the segment.

12. The processor readable medium of claim 10 encoded with instructions that, if executed, result in:

generating reference identifiers for all segments of the packet and transmitting information mapping the generated reference identifiers with their associated segments along with the packet.

13. The processor readable medium of claim 12, wherein the request identifies the portion of the segments using the reference identifiers.

14. A method, comprising:

receiving and demodulating audio tones into a packet having a header and a payload, wherein the payload includes data and redundant data corresponding thereto;

examining the payload data using the corresponding redundant data to identify a portion of the payload data as being associated with errors;

generating and sending a request for error correction bits for the identified portion;

receiving and demodulating subsequently received audio tones into the requested error correction bits; and

correcting the payload data using the received error correction bits.

15. The method of claim 14, further comprising generating and sending the request for the error correction bits for only a subset of the payload data.

16. The method of claim 14, further comprising:

detecting errors in the corrected payload using error detection bits included in the packet; and

if errors are detected, requesting re-transmission of the packet.

17. The method of claim 14, wherein the redundant data comprises Forward Error Correction (FEC) information or Cyclic Redundancy Check (CRC) information.

18. A method, comprising:

generating redundant data corresponding to a packet payload;

modulating a packet containing the payload data and the redundant data using an In-Band Signaling (IBS) modem and transmitting signals resulting therefrom over a voice band of a wireless telecommunications network;

receiving back a response requesting error correction bits for an identified portion of the payload data; and

modulating the error correction bits for the identified portion of the payload data and transmitting signals resulting therefrom over the voice band of the wireless telecommunications network.

19. The method of claim 18, wherein the redundant data comprises error correction information or error detection information.

20. The method of claim 18, further comprising:

performing a series of transmissions providing Forward Error Correction (FEC) bits for a particular portion of the payload data, wherein each transmission increments the number of FEC bits included therein for the particular payload data.

21. The method of claim 18, wherein the initially transmitted signals represent both payload data and the redundant data, and wherein the subsequently transmitted signals represent only redundant data, and the method further comprises:

transmitting signals representing the payload data after providing the error correction bits.