System and method for reliably communicating the content of a live data stream

• US 20030226089A1
• Filed: 02/14/2003
• Published: 12/04/2003
• Est. Priority Date: 02/15/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Digital Fountain Incorporated (Qualcomm, Inc.)
• Inventors: Lassen, Soren, Luby, Michael, Horn, Gavin, Goyal, Vivek, Rasmussen, Jens, Shokrollahi, Amin, Dobyns, Barry
• Granted Patent: US 7,249,291 B2
• Time in Patent Office: Days
• US Class Current: 714/758
• CPC Class Codes: H04L 1/004 by using forward error control H04L1/0618 takes precedence; coding, decoding or code conversion, for error detection or correction H03M13/00
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint
• CPC Class Codes: H04L 2001/0096 Channel splitting in point-to-point links
• CPC Class Codes: H04N 21/234327 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/2383 Channel coding or modulation of digital bit-stream, e.g. QPSK modulation arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/2385 Channel allocation H04N21/266 takes precedence; Bandwidth allocation H04N21/24 takes precedence ; allocation of channels according to the instantaneous demands of the users in time-division multiplex systems H04J3/1682; admission control, resource allocation in open networks H04L12/5692; arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896; negotiating bandwidth in wireless networks H04W28/16
• CPC Class Codes: H04N 21/2389 Multiplex stream processing, e.g. multiplex stream encrypting
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/4382 Demodulation or channel decoding, e.g. QPSK demodulation analog front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/4385 Multiplex stream processing, e.g. multiplex stream decrypting
• CPC Class Codes: H04N 21/631 Multimode Transmission, e.g. transmitting basic layers and enhancement layers of the content over different transmission paths or transmitting with different error corrections, different keys or with different transmission protocols
• CPC Class Codes: H04N 21/64792 Controlling the complexity of the content stream, e.g. by dropping packets intermediate media network packet handling H04L65/765; proxy provisioning conversion or adaptation for reducing the amount or size of exchanged application data H04L67/5651; negotiation of resources in wireless networks H04W28/16
• CPC Class Codes: H04N 21/8456 by decomposing the content in the time domain, e.g. in time segments

Abstract

A method for communicating the content of a live data stream to a receiver using a plurality of channels comprising two encoder channels used to encode the live data content prior to transmission. Initially a plurality of segments of a live data stream are received, wherein each segment contains segment data. A forward error correction algorithm is applied to each segment'"'"'s data, thereby producing FEC-encoded segment data. The FEC-encoded segment data is contained within an FEC-encoded block, resulting in a corresponding plurality of FEC-encoded blocks being generated. Each FEC-encoded block is copied to a sub-channel on both a first encoder channel and a second encoder channel, resulting in a plurality of FEC-encoder blocks residing on the first and second encoder channels. The first and second encoder channels differ in the number of sub-channels they contain (interleaving depth), and accordingly the arrangement of the FEC-encoded blocks in the first and second encoder channels are different. A first cross-section of the FEC-encoded segment data contained within the FEC-encoded blocks resident in the first encoder channel is added to a first transmit block T₀. Similarly, A first cross-section of the FEC-encoded segment data contained within the FEC-encoded blocks resident in the second encoder channel is added to a second transmit block T₁. The first and second transmit blocks are then communicated to the receiver.

Claims

1. A method for communicating the content of a live data stream to a receiver using a plurality of channels comprising one or more main channels and one or more booster channels, each of the main and booster channels having at least two sub-channels, the method comprising:

receiving a first segment of a live data stream, the first segment S₀ containing first segment data;

applying a forward error correction algorithm the first segment data to produce a corresponding transmit block T₀;

dividing the T₀ block into two or more T₀ sub-blocks, wherein each of the two or more T₀ sub-blocks comprise substantially distinct FEC-encoded first segment data;

transmitting a first of the two or more T₀ sub-blocks to a receiver on a first main sub-channel;

receiving a second segment of the live data stream, the second segment S₁ containing second segment data;

applying a forward error correction algorithm to the second segment data to produce a transmit block T₁;

dividing the T₁ block into two or more T₁ blocks, wherein each of the two or more T₁ blocks comprise substantially distinct FEC-encoded second segment data;

transmitting substantially concurrently, the second of the two or more T₀ sub-blocks on the first main sub-channel and a first of the two or more T₁ sub-blocks on a second main sub-channel; and

transmitting substantially concurrently, the first T₀ sub-block on a first booster sub-channel, and the first T₁ sub-block on a second booster sub-channel,

wherein the second T₀ sub-block, the first T₁ sub-block, the first T₀ sub-block, and the first T₁ sub-block are all transmitted substantially-concurrently.

2. The method recited in claim 1, wherein the T₀ and T₁ blocks are divided into three of more T₀ sub-blocks and three or more T₁ sub-blocks, respectively, and wherein each of the three or more T₀ and T₁ sub-blocks comprise substantially distinct data;

the method further comprising;

receiving a third segment of the live data stream, the third segment S₂ containing third segment data;

applying a forward error correction algorithm to the third segment data to produce a transmit block T₂;

dividing the T₂ block into three or more T₂ sub-blocks, wherein each of the three or more T₂ sub-blocks comprises substantially distinct third segment data;

transmitting the third of the three or more T₀sub-blocks on the first main sub-channel after the second T₀ sub-block;

transmitting a second of the three or more T₁ sub-blocks on the second main sub-channel after the first T₁ sub-block; and

transmitting a first of the three or more T₂ sub-blocks to the receiver on a third main sub-channel,

wherein the third T₀ sub-block, the second T₁ sub-block, and the first T₂ sub-block are all transmitted substantially concurrently.

3. The method recited in claim 2, further comprising:

transmitting on the first booster sub-channel, the first of the three of more T₂ sub-blocks after the first T₁ block;

transmitting on the second booster sub-channel, the first T₁ sub-block after the first T₀ sub-block; and

transmitting of the third booster sub-channel, the second T₁ sub-block after the second T₀ sub-block.

4. The method recited in claim 1, wherein applying a forward error correction algorithm to two or more subsets of the first and second segment data comprises applying a Luby Transform to the first and second segment data.

5. The method recited in claim 1, wherein applying a forward error correction algorithm to two or more subsets of the first and second segment data comprises applying a Reed-Solomon transform to the first and second segment data.

6. The method recited in claim 1, further comprising:

receiving the first T₀ sub-block via the first main sub-channel; and

receiving the second T₀ sub-block via the first channel and the first T₁ sub-block via the second channel substantially concurrently.

7. The method recited in claim 1, wherein the receiver has insufficient bandwidth to receive the transmitted blocks on the main and booster channels simultaneously, the method further comprising:

receiving a least one of the two or more T₀ sub-blocks via the booster channel;

recovering the first segment data from the at least one received T₀ sub-blocks;

thereafter, switching receiver reception to the main channel;

receiving at least one of the two or more T₁ sub-blocks via the second main sub-channel; and

recovering the second segment data from the at least one received T₁ sub-blocks.

8. The method recited in claim 2, wherein the receiver has insufficient bandwidth to receive the transmitted blocks on the main and booster channels simultaneously, the method further comprising:

receiving a least one of the two or more T₀ sub-blocks via the booster channel;

recovering the first segment data from the at least one received T₀ sub-blocks;

thereafter, switching receiver reception to the main channel;

receiving at least one of the three or more T₁ sub-blocks via the second main sub-channel;

recovering the second segment data from the at least one received T₁ sub-blocks;

receiving at least one of the three or more T₂ sub-blocks via the third main sub-channel; and

recovering the third segment data from the at least one received T₂ sub-blocks.

9. A system operable to communicate the content of a live data stream to a receiver via a plurality of channels, the system comprising:

a receiver operable to receive first and second segments of a live data stream, the first and second segments containing first and second segment data, respectively;

an encoder operable to apply a forward error correction algorithm to the first segment data and to the second segment data to produce a corresponding first transmit block T₀ and a second transmit block T₁;

a block partitioner operable to divide each of the first and second transmit blocks T0 and T1 into a plurality of sub-blocks; and

a transmitter operable to transmit the T₀ sub-blocks on a first channel and the plurality of T₁ sub-blocks on a second channel.

10. The system recited in claim 9, wherein the encoder means comprises an information additive code generator.

11. The system recited in claim 9, further comprising a dual channel receiver operable to receive the one or more T₀ data blocks on a first channel and the one or more T₁ data blocks on a second channel

12. The system recited in claim 9, further comprising a switchable, single-channel receiver configured to switch reception between the first channel to receive the one or more T₀, and the second channel to receive the one or more T₁ data blocks.

13. The system recited in claim 12, further comprising a decoder operable to recover the first segment data from the received one or more T₀ data blocks and the second segment.

14. The system recited in claim 13, wherein the decoder comprises an information additive code decoder.

15. A method for communicating the content of a live data stream to a receiver on a plurality of channels, the plurality of channels comprising at least two alternately-switched main channels, the method comprising:

receiving a first segment of a live data stream, the first segment S₀ containing first segment data;

applying a forward error correction algorithm to the first segment data to produce a corresponding transmit block T₀;

dividing the T₀ block into two or more T₀ sub-blocks, wherein each of the two or more T₀ sub-blocks comprises substantially distinct first segment data;

transmitting a first of the two or more T₀ sub-blocks in a first packet on a first alternately-switched main channel;

receiving a second segment of a live data stream, the second segment S₁ containing second segment data;

applying a forward error correction algorithm to the second segment data to produce a corresponding transmit block T₁;

dividing the T₁ block into two or more T₁ sub-blocks, wherein each of the two or more T₁ sub-blocks comprises substantially distinct second segment data;

transmitting in a second packet and on a second alternately-switched main channel, a second of the two or more T₀ sub-blocks and a first of the two or more T₁ sub-blocks; and

transmitting in a third packet and on the first alternately-switched main channel, a second of the two or more T₁ sub-blocks.

16. The method recited in claim 15, wherein the second packet is transmitted on the second main channel after the first packet on the first main channel, and the third-packet is transmitted on the first alternately-switched main channel after the second packet is transmitted on the second main channel.

17. The method recited in claim 16, wherein no packet is transmitted on the second channel during transmission of the first packet on the first channel, and no packet is transmitted on the first channel when the second packet is transmitted on the second channel.

18. The method recited in claim 15, wherein the T₀ and T₁ blocks are divided into three of more T₀ sub-blocks and three or more T₁ sub-blocks, respectively, and wherein each of the three or more T₀ and T₁ sub-blocks comprise substantially distinct data;

the method further comprising;

receiving a third segment of the live data stream, the third segment S₂ containing third segment data;

applying a forward error correction algorithm to the third segment data to produce a corresponding transmit block T₂; and

dividing the T₂ block into three or more T₂ sub-blocks, wherein each of the three or more T₂ sub-blocks comprises substantially distinct third segment data;

wherein transmitting a third packet on the first channel comprises transmitting in the third packet, a third of the three or more T₀ sub-blocks, the second T₁ sub-block, and a first of the three or more T₂ sub-blocks.

19. The method recited in claim 18, further comprising:

transmitting a fourth packet on a first booster channel substantially concurrently with the second packet, the fourth packet comprising the first T₀ sub-block;

transmitting a fifth packet on a second booster channel substantially concurrently with the third packet, the fifth packet comprising the first T₁ sub-block; and

transmitting a sixth packet on the first booster channel substantially concurrently with the third packet, the sixth packet comprising the first T₂ sub-block.

20. The method recited in claim 15, further comprising:

switching receiver reception between the first and second channels to receive at least one of the first, second, or third packets; and

recovering the first segment data from the at least one received data packets.

21. The method recited in claim 15, wherein the receiver has insufficient bandwidth to receive the transmitted blocks on the main and booster channels simultaneously, the method further comprising:

receiving at least one of the two or more T₀ sub-blocks via the booster channel;

recovering the first segment data from the at least one received T₀ sub-blocks;

thereafter, switching receiver reception to the main channel;

receiving at least one of the two or more T₁ sub-blocks via the first or the second main channels; and

recovering the second segment data from the at least one received T₁ sub-blocks.

22. A method for communicating the content of a live data stream to a receiver via a plurality of channels, the plurality of channels comprising at least one main channel, at least one long protection channel, and at least one hopper channel, the method comprising:

receiving a first segment of a live data stream, the first segment S₁ containing first segment data;

applying a forward error correction algorithm to the first segment data to produce a transmit block T₁;

dividing the T₁ block into two or more T₁ sub-blocks, wherein each of the two or more T₁ sub-blocks comprises substantially distinct first segment data;

transmitting on a first main channel, at least one fewer T₁ sub-blocks than the total two or more T₁ sub-blocks;

receiving a second segment of the live data stream, the second segment S₂ containing second segment data;

applying a forward error correction algorithm to the second segment data to produce a transmit block T₂;

dividing the T₂ block into two or more T₂ sub-blocks, wherein each of the two or more T₂ sub-blocks comprises substantially distinct second segment data;

transmitting on a second main channel, at least one fewer T₂ sub-blocks than the total two or more T₂ sub-blocks;

combining the transmitted T₁ and T₂ sub-blocks to produce a T₁₊₂ block; and

transmitting the T₁₊₂ block on a first long protection channel.

23. The method recited in claim 22 further comprising transmitting on a hopper channel, one of the at least one T₁ sub-blocks not transmitted on the first main channel.

24. The method recited in claim 23, further comprising thereafter, transmitting on the hopper channel one of the at least one T₂ sub-blocks not transmitted on the second main channel.

25. The method recited in claim 22, wherein applying a forward error correction algorithm to the first and second segment data comprises applying a Luby transform to the first and second segment data.

26. The method recited in claim 22, wherein applying a forward error correction algorithm to the first and second segment data comprises applying a Reed-Solomon transform to the first and second segment data.

27. A method for communicating the content of a live data stream to a receiver via a plurality of channels, the method comprising:

receiving a plurality of segments of a live data stream, each segment comprising segment data;

for each of the plurality of segments, applying a forward error correction algorithm to the segment data to produce FEC-encoded segment data, whereby a respective plurality of FEC-encoded blocks containing the FEC-encoded segment data are created;

assigning each of the plurality of FEC-encoded blocks to a sub-channel with a first encoder channel, and to a sub-channel within a second encoder channel, wherein the first encoder channel and the second encoder channel each have a different number of sub-channels;

adding into a first transmit block T₀, a first cross-section of the FEC-encoded segment data contained within the FEC-encoded blocks resident on the sub-channels in the first encoder channel; and

adding into a second transmit block T₁, a first cross-section of the FEC-encoded segment data contained within the FEC-encoded blocks resident on the sub-channels in the second encoder channel.

28. The method recited in claim 27, further comprising:

transmitting the first transmit block T₀ on a first transmit channel; and

transmitting the second transmit block T₁ on a second transmit channel.

29. The method recited in claim 27, further comprising:

adding into a third transmit block T₂, a second cross-section of the FEC-encoded segment data contained within the FEC-encoded blocks resident on the sub-channels in the first encoder channel; and

adding into a fourth transmit block T₃, a section cross-section of the FEC-encoded segment data contained within the FEC-encoded blocks resident on the sub-channels in the second encoder channel.

30. The method recited in claim 29, further comprising:

transmitting the third transmit block T₂ on the first transmit channel after transmission of the first transmit block T₀; and

transmitting the fourth transmit block T₃ on the second transmit channel after transmission of the second transmit block T₁.

31. The method recited in claim 27, wherein applying a forward error correction algorithm to each of the three or more segments comprises applying a Luby Transform to each of the plurality of segments.

32. The method recited in claim 27, wherein applying a forward error correction algorithm to each of the three or more segments comprises applying a Reed-Solomon algorithm to each of the plurality of segments.

33. A system operable to communicate the content of a live data stream to a receiver via a plurality of channels, the plurality of channels comprising encoder channels, the system comprising:

a receiver operable to receive a plurality of segments of a live data stream, wherein each segment S_i comprise segment data;

an encoder operable to apply a forward error correction algorithm to the segment data with each segment Si'"'"'s data to produce a corresponding plurality of FEC-encoded blocks E_i comprising corresponding FEC-encoded segment data;

means for assigning each FEC-encoded block E_i to to at least two encoder channels, wherein the assignment results in at least one encoder channel having a different interleaving depth than the second of the at least two encoder channels;

a transmitter configured to transmit a;

first cross-sectional portion of the FEC-encoded data contained within the first encoder channel in a first transmit block T₀, and a first cross-sectional portion of the FEC-encoded data contained within the second encoder channel in a second transmit block T₁.

34. The system recited in claim 33, wherein the transmitter comprises a multiple channel receiver configured to transmit the first transmit block T₀ on a first transmitter channel and the second transmit block T₁ on a second transmitter channel.

35. The system recited in claim 34, further comprising a switchable, single-channel receiver configured to switch reception between the first channel to receive the first transmit block T₀, and the second channel to receive the second transmit block T₁.

36. The system recited in claim 35, further comprising a decoder operable to recover the first segment data from the received T₀ data block and the second segment data from the received T₁ transmit block.

37. The system recited in claim 35, wherein the encoder comprises an information additive code encoder and the decoder comprises an information additive code decoder.