Enhancing capacity of a direct communication link
View Patent ↗Capacity enhancement of a direct communication link using a variable redundancy delivery network. An estimated information rate between a source node and a terminal node may be partitioned into a first information rate provided via the direct communication link and a second information rate to be provided via the variable redundancy delivery network. One or more parameters of the variable redundancy delivery network may be calculated to provide the second information rate based on a non-uniform probability density of messages requested by the terminal node. Capacity and reliability of storage media devices in the variable redundancy delivery network may be traded off to provide the second information rate. The variable redundancy delivery network may implement various coding schemes and per-message coding rates that may be determined based on the non-uniform probability distribution of the source message library.
1. A communication system comprising:
a network gateway device on a mobile platform coupled with a plurality of user communication devices on the mobile platform via respective local communication links;
a ground station coupled with a network, the network comprising at least one source node for a message library;
a direct communication link coupling the ground station to the network gateway device, the direct communication link to deliver messages of the message library to the network gateway device from the ground station in response to requests by the plurality of user communication devices; and
a variable redundancy delivery network on the mobile platform and coupled with the network gateway device, the variable redundancy delivery network comprising one or more intermediate storage nodes storing the messages with variable redundancy for delivery to the plurality of user communication devices in response to subsequent ones of the requests for the messages based on a non-uniform probability density of the requests for the messages, wherein at least one parameter of the variable redundancy delivery network is selected based at least in part on a desired information rate to be provided by the variable redundancy delivery network, and wherein the non-uniform probability density of the messages is determined based on a number of the requests for the messages in a rolling time period.
2. The communication system of claim 1 , wherein the variable redundancy for the storing of the messages comprises a storage policy for increasing redundancy based on a number of times the messages have been delivered to the plurality of user communication devices.
3. The communication system of claim 2 , wherein the storage policy is determined based at least in part on a storage size of the one or more intermediate storage nodes or a number of the one or more intermediate storage nodes.
4. The communication system of claim 2 , wherein the storage policy is determined based at least in part on a message retrieval reliability associated with the stored messages.
5. The communication system of claim 2 , wherein the storage policy is determined based on an optimization process applied to a function of a probability of message availability.
6. The communication system of claim 2 , wherein the storage policy is adapted based at least in part on an identified failure of a storage node of the variable redundancy delivery network.
7. The communication system of claim 2 , wherein the storage policy is adapted based at least in part on an identified change of the non-uniform probability density of the messages.
8. The communication system of claim 2 , wherein the storage policy comprises message replication, parity coding, Reed-Solomon coding, or a combination thereof.
9. The communication system of claim 1 , wherein the one or more intermediate storage nodes of the variable redundancy delivery network are configured in a non-redundant disk array configuration.
10. The communication system of claim 1 , wherein the direct communication link comprises a satellite communication link between the ground station and the network gateway device.
11. A method for capacity enhancement of a communications system, the method comprising:
coupling a network gateway device on a mobile platform with a plurality of user communication devices on the mobile platform via respective local communication links;
coupling the network gateway device with a ground station via a direct communication link, the ground station coupled with a network, the network comprising at least one source node for a message library;
coupling the network gateway device with a variable redundancy delivery network on the mobile platform, the variable redundancy delivery network comprising one or more intermediate storage nodes, wherein at least one parameter of the variable redundancy delivery network is selected based at least in part on a desired information rate to be provided by the variable redundancy delivery network;
delivering messages of the message library to the network gateway device from the ground station in response to requests by the plurality of user communication devices;
determining a non-uniform probability density of the messages based on a number of the requests for the messages in a rolling time period;
storing the messages for delivery from the variable redundancy delivery network to the plurality of user communication devices with variable redundancy based on the non-uniform probability density of the requests for the messages; and
delivering the messages to the plurality of user communication devices from the variable redundancy delivery network in response to subsequent ones of the requests for the messages.
12. The method of claim 11 , wherein the variable redundancy for the storing of the messages comprises a storage policy for increasing redundancy based on a number of times the messages have been delivered to the plurality of user communication devices.
13. The method of claim 12 , wherein the storage policy is determined based at least in part on a storage size of the one or more intermediate storage nodes or a number of the one or more intermediate storage nodes.
14. The method of claim 12 , wherein the storage policy is determined based at least in part on a message retrieval reliability associated with the stored messages.
15. The method of claim 12 , wherein the storage policy is determined based on an optimization process applied to a function of a probability of message availability.
16. The method of claim 12 , further comprising:
identifying a failure of a storage node of the variable redundancy delivery network; and adapting the storage policy based at least in part on the identified failure of the storage node.
17. The method of claim 12 , further comprising:
identifying a change in the non-uniform probability density of the messages; and
adapting the storage policy based at least in part on the identified change in the non-uniform probability density of the messages.
18. The method of claim 12 , wherein the storage policy comprises message replication, parity coding, Reed-Solomon coding, or a combination thereof.
19. The method of claim 11 , wherein the one or more intermediate storage nodes of the variable redundancy delivery network are configured in a non-redundant disk array configuration.
20. The method of claim 11 , wherein the direct communication link comprises a satellite communication link between the ground station and the network gateway device.
21. A non-transitory computer readable medium storing code for capacity enhancement of a communications system comprising a network gateway device on a mobile platform coupled with a ground station via a direct communication link and a variable redundancy delivery network on the mobile platform, the variable redundancy delivery network comprising one or more intermediate storage nodes, wherein at least one parameter of the variable redundancy delivery network is selected based at least in part on a desired information rate to be provided by the variable redundancy delivery network, the ground station coupled with a network that comprises at least one source node for a message library, the code comprising instructions executable by a processor for:
coupling the network gateway device with a plurality of user communication devices on the mobile platform via respective local communication links;
delivering messages of the message library to the network gateway device from the ground station in response to requests by the plurality of user communication devices;
determining a non-uniform probability density of the messages based on a number of the requests for the messages in a rolling time period;
storing the messages for delivery from the variable redundancy delivery network to the plurality of user communication devices with variable redundancy based on the non-uniform probability density of the requests for the messages; and
delivering the messages to the plurality of user communication devices from the variable redundancy delivery network in response to subsequent ones of the requests for the messages.