Cooperative Subspace Demultiplexing in Content Delivery Networks

• US 20140146924A1
• Filed: 01/30/2014
• Published: 05/29/2014
• Est. Priority Date: 05/14/2002
• Status: Active Grant

• Current Assignee: Genghiscomm Holdings, LLC
• Original Assignee: Genghiscomm Holdings, LLC
• Inventors: Shattil, Steve J.
• Granted Patent: US 9,819,449 B2
• Time in Patent Office: Days
• US Class Current: 375/340
• CPC Class Codes: H04B 7/026 Co-operative diversity, e.g. using fixed or mobile stations as relays
• CPC Class Codes: H04J 13/0003 Code application, i.e. aspects relating to how codes are applied to form multiplexed channels
• CPC Class Codes: H04J 13/004 Orthogonal
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0077 Cooperative coding
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 1/0681 adapting space time parameters, i.e. modifying the space time matrix
• CPC Class Codes: H04L 2001/0097 Relays
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/2614 Peak power aspects
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 5/0021 in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams

Abstract

A source node selects a plurality of original data components to transfer to at least one destination node. A plurality of transmitting nodes cooperatively encodes the original data components to generate a plurality of subspace coded components and a corresponding code matrix. Each of the transmitting nodes transmits a subset of the plurality of subspace coded components and corresponding code matrix, wherein at least one of the transmitting nodes has a rank that is insufficient for decoding the plurality of subspace coded components. A destination node may employ a plurality of receiving nodes to cooperatively receive a plurality of subspace coded components and their corresponding code vectors, wherein the rank of at least one of the receiving nodes is insufficient for decoding the subspace coded components. The destination node builds up the dimension of the subspace spanned by code vectors it collects from the receiving nodes and then decodes the subspace coded components.

Claims

1. A processing method for retrieving data in a content delivery network, comprising:

selecting a plurality of receiving nodes to cooperatively receive a plurality of linearly independent coded components and a plurality of corresponding code vectors, wherein a rank of at least one of the receiving nodes is insufficient for decoding the coded components;

building up a dimension of a subspace spanned by collected code vectors by collecting the coded components and the corresponding code vectors from the plurality of receiving nodes; and

decoding the coded components.

2. The processing method recited in claim 1, wherein building up comprises, in response to a user input, selecting a destination node from a plurality of user-selectable client devices, and combining the coded components and the corresponding code vectors at the destination node.

3. The processing method recited in claim 1, wherein at least one of selecting and building comprises at least one of ensuring that a code matrix generated from the corresponding code vectors has sufficient rank to enable decoding, and ensuring the code matrix is sufficiently well-conditioned to permit decoding.

4. The processing method recited in claim 1, further comprising transmitting at least one acknowledgement to at least one source node upon at least one of receiving a coded component and decoding the coded components.

5. The processing method recited in claim 1, wherein decoding is configured for decoding at least one of a set of coded components, the set comprising block coded components and sliding window coded components.

6. A non-transitory computer-readable medium storing a computer program configured for implementing the method of claim 1.

7. A method for processing data in a content delivery network, comprising:

determining a required number of degrees of freedom for decoding a set of linearly coded packets;

based on the required number of degrees of freedom, selecting at least one additional receiving node for cooperatively receiving at least one coded packet and associated code vector;

collecting a plurality of coded packets and associated code vectors from a plurality of cooperating receiving nodes, including the at least one additional receiving node, to provide the required number of degrees of freedom; and

decoding the plurality of coded packets.

8. The processing method recited in claim 7, wherein the plurality of receiving nodes comprises the destination node and at least one user-selectable client device, and wherein collecting comprises, in response to a user input, selecting one of the at least one user-selectable client device as a new destination node and combining the plurality of coded packets and associated code vectors at the new destination node to enable the new destination node to decode the plurality of coded packets.

9. The method recited in claim 7, wherein at least one of selecting and collecting comprises ensuring that a code matrix produced from the associated code vectors is sufficiently well-conditioned to permit decoding.

10. The method recited in claim 7, further comprising transmitting at least one acknowledgement to at least one source node upon at least one of collecting a coded packet and decoding the coded packets.

11. The method recited in claim 7, wherein decoding is configured to employ at least one of block codes and sliding window codes.

12. A non-transitory computer-readable medium storing a computer program configured for implementing the method of claim 7.

13. A method for receiving data in a content delivery network, comprising:

connecting to a first network channel and at least a second network channel to simultaneously receive a plurality of linearly coded packets and corresponding code vectors transmitted from a source node;

receiving a first subset of the plurality of linearly coded packets and corresponding code vectors on the first network channel and receiving a second subset of the plurality of linearly coded packets and corresponding code vectors on the at least second network channel, wherein at least one of the first subset and the second subset has a rank that is insufficient for decoding the plurality of linearly coded packets, and wherein a sum of ranks of the first subset and the second subset is sufficient for decoding the plurality of linearly coded packets;

combining the first subset with the second subset; and

decoding the plurality of linearly coded packets.

14. The processing method recited in claim 13, wherein receiving comprises, in response to a user input, selecting a destination node from a plurality of user-selectable client devices, and wherein combining comprises combining the first subset and the second subset at the destination node.

15. The method recited in claim 13, wherein the first network channel resides on a first network and the at least second network channel resides on a second network, the second network different than the first network.

16. The method recited in claim 13, further comprising monitoring at least one real-time property of the first network channel and the at least second network channel;

and instructing the source to adjust at least one of coding and transmitting the plurality of linearly coded packets and corresponding code vectors.

17. The method recited in claim 13, wherein receiving the first subset and receiving the second subset comprises ensuring that a code matrix produced from the corresponding code vectors is sufficiently well-conditioned to permit decoding.

18. The method recited in claim 13, further comprising transmitting at least one acknowledgement to the source node upon at least one of collecting a linearly coded packet and decoding the plurality of linearly coded packets.

19. The method recited in claim 13, wherein decoding comprises decoding at least one of a set of coded packets, the set comprising block coded packets and sliding window coded packets.

20. A non-transitory computer-readable medium storing a computer program implementing the method of claim 13.