Efficient error correction scheme for data transmission in a wireless in-band signaling system

• US 8,418,039 B2
• Filed: 07/13/2010
• Issued: 04/09/2013
• 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.
• Primary Examiner(s): Merant, Guerrier
• Application Number:
  US12/835,519
• Publication Number:
  US 20110029832A1
• Time in Patent Office: 1,001 Days
• Field of Search: None
• US Class Current: 714/776
• 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 memory device having instructions stored thereon that, in response to execution by a processing device, cause the processing device to perform operations comprising:

recovering digital data from a voice band of a wireless telecommunications network, said recovering including demodulating audio tones from the voice band using an in-band signaling modem, wherein the digital data comprises a packet having a header and a payload, wherein the payload includes a plurality of segments each having redundant data corresponding thereto;

examining the segments using their corresponding redundant data and identifying one(s) of the segments that are associated with error(s);

transmitting a signal responsive to identifying the one(s) of the segments that are associated with the error(s);

responsive to the transmitting the signal identifying the one(s) of the segments that are associated with the error(s), subsequently recovering additional digital data from the voice band of the wireless telecommunications network, said subsequent recovering including demodulating additional audio tones from the voice band using the in-band signaling modem, wherein the additional digital data comprises error correction bits;

correcting the payload of the packet using the error correction bits;

receiving via the voice band of the wireless telecommunications network a plurality of identifiers, each identifier corresponding to a different one of the segments of the plurality of segments;

inserting into the signal only those identifiers of the recovered plurality of identifiers that correspond to the identified one(s) of the segments; and

subsequently recovering the additional digital data from the voice band of the wireless telecommunications network responsive to transmitting the signal containing only those identifiers of the recovered plurality of identifiers that correspond to the identified one(s) of the segments.

2. The memory device of claim 1, wherein the operations further comprise:

performing bit correction on the identified one(s) of the segments using respective ones of the error correction bits to identify any such segments that correspond with an increase in associated error(s); and

generating and sending a request for additional error correction bits for the identified one(s) of the segments having the increase in the associated error(s).

3. The memory device of claim 2, wherein the operations further comprise:

repeating bit 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 error(s) 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 error(s) remaining.

4. The memory device of claim 1, wherein the operations further comprise:

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

5. The memory device of claim 4, wherein the series of responses provide gradually increasing amounts of error correction information for a particular one of the segments.

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

7. The memory device of claim 6, wherein the operations further comprise:

examining the corrected payload using error detection bits included with the packet to determine whether there are uncorrected error(s) remaining; and

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

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

9. The memory device of claim 1, wherein said redundant data comprises at least one of error detection bits and error correction bits.

10. A memory device having instructions stored thereon that, in response to execution by a processing device, cause the processing device to perform operations comprising:

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

modulating the segmented packet payload 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;

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;

transmitting via the voice band of the wireless telecommunications network a plurality of identifiers, each identifier corresponding to a different one of the segments of the segmented packet payload;

examining the received response to ascertain which one(s) of the plurality of identifiers is included therein; and

modulating the error correction bits for the segment identified in the request responsive to ascertaining which one(s) of the plurality of identifiers is included in the received response.

11. The memory device of claim 10, wherein the operations further comprise:

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.

12. The memory device of claim 11, wherein the additional error correction bits corresponding to the segment comprise more information than the error correction bits corresponding to the segment.

13. The memory device of claim 11, wherein the operations further comprise:

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

14. The memory device of claim 13, wherein the request identifies the portion of the segments using the reference identifiers.

15. A method, comprising:

recovering digital data from a voice channel of a wireless telecommunications network, said recovering including demodulating audio tones from the voice band using an in-band signaling modem, wherein the digital data comprises a packet having a header and a payload, wherein the payload includes data and redundant data corresponding thereto;

examining the payload using the corresponding redundant data to identify a portion of the payload as being associated with error(s);

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

responsive to sending the request for the error correction bits for the identified portion, subsequently recovering additional digital data from the voice band of the wireless telecommunications network, said subsequent recovering including demodulating additional audio tones from the voice channel using the in-band signaling modem, wherein the additional digital data comprises error correction bits;

correcting the payload using the error correction bits;

receiving via the voice channel of the wireless telecommunications network a plurality of identifiers, each identifier corresponding to a different segment of the packet;

inserting into the request only those identifiers of the recovered plurality of identifiers that correspond to segment(s) of the identified portion; and

subsequently recovering the additional digital data from the voice channel of the wireless telecommunications network responsive to sending the request containing only those identifiers of the recovered plurality of identifiers that correspond to the segment(s) of the identified portion.

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

17. The method of claim 15, further comprising:

detecting error(s) in the corrected payload using error detection bits included in the packet; and

if error(s) are detected, requesting re-transmission of the packet.

18. The method of claim 15, wherein the redundant data comprises Forward Error Correction (FEC) information or Cyclic Redundancy Check (CRC) information.

19. 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 initial signals resulting therefrom over a voice channel of a wireless telecommunications network;

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

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

transmitting via the voice channel of the wireless telecommunications network a plurality of identifiers, each identifier corresponding to a different segment of the packet payload;

examining the received response to ascertain which one(s) of the plurality of identifiers is included therein; and

modulating the error correction bits for the identified portion responsive to ascertaining which one(s) of the plurality of identifiers is included in the received response.

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

21. The method of claim 19, 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.

22. The method of claim 19, 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.