Dynamic bandwidth resource allocation for satellite downlinks

• US 9,118,455 B2
• Filed: 12/13/2013
• Issued: 08/25/2015
• Est. Priority Date: 06/16/2009
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Agarwal, Anil
• Primary Examiner(s): LOUIS, VINNCELAS
• Application Number:
  US14/106,301
• Publication Number:
  US 20140177521A1
• Time in Patent Office: 620 Days
• Field of Search: 370/316, 370/329, 370/392, 455/522, 716/106
• US Class Current: 1/1
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/18515 Transmission equipment in satellites or space-based relays
• CPC Class Codes: H04B 7/18539 Arrangements for managing radio, resources, i.e. for establishing or releasing a connection
• CPC Class Codes: H04B 7/2123 Variable assignment, e.g. demand assignment
• CPC Class Codes: H04B 7/22 Scatter propagation systems , e.g. ionospheric, tropospheric or meteor scatter
• CPC Class Codes: H04L 5/0096 Indication of changes in allocation
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

Satellite communications systems, methods, and related devices are described. In one embodiment, a satellite communications system is configured to dynamically allocate bandwidth among different downlink beams. The satellite may receive and compile traffic measurements and terminal parameters. The satellite may be configured with different downlink beam coverage areas, and may dynamically allocate downlink bandwidth and particular frequency channels to different beam coverage areas based on the measurements and parameters. The satellite may also assign frequency channels and time slots based on such measurements and parameters.

Claims

1. A method performed by a satellite resource control unit for allocating downlink resources in a multi-beam satellite communications network having a plurality of terminals in each of a plurality of beams of a multi-beam satellite, the downlink resources defined in resource units, the method comprising:

identifying, at the satellite resource control unit, an estimated downlink resource unit demand for each of the plurality of beams for a future defined time duration responsive to downlink traffic data for each of the plurality of beams monitored before the future defined time duration;

identifying an amount of allocatable resource units for the future defined time duration for the multi-beam satellite communications network;

dynamically allocating, responsive to the estimated downlink resource unit demand for each of the plurality of beams, a subset of the amount of allocatable resource units to each of the plurality of beams to generate a per-beam downlink resource unit allocation for the future defined time duration;

identifying, in each of the plurality of beams, an estimated downlink resource unit demand for each of a plurality of modulation and coding groups;

identifying, in each of the plurality of modulation and coding groups in each of the plurality of beams, an estimated downlink resource unit demand for each of a plurality of traffic classes; and

dynamically allocating, responsive to the estimated downlink resource unit demand for each of the plurality of modulation and coding groups in each respective beam, the allocated resource units for each beam among the plurality of modulation and coding groups for the future defined time duration, wherein the allocating comprises allocating the allocated resource units in each of the plurality of modulation and coding groups in each of the plurality of beams among the plurality of traffic classes.

2. The method of claim 1, wherein identifying the estimated downlink resource unit demand for each of the plurality of beams comprises:

measuring, on the multi-beam satellite, an amount of traffic directed to each beam.

3. The method of claim 1, wherein identifying the estimated downlink resource unit demand for each of the plurality of beams comprises:

receiving traffic measurements from at least a subset of the plurality of terminals in each beam.

4. The method of claim 3, wherein,

the traffic measurements are received at a ground-based network control center;

and

the dynamic allocation among the plurality of beams is performed by the ground-based network control center.

5. The method of claim 1, wherein identifying the estimated downlink resource unit demand for each of the plurality of beams comprises:

measuring queue sizes attributable to each beam.

6. The method of claim 1, wherein identifying the estimated downlink resource unit demand for each of the plurality of beams comprises:

calculating dropped packets for each beam.

7. The method of claim 1, wherein a relative allocation among the plurality of traffic classes is different in each modulation and coding group within a beam of the plurality of beams.

8. The method of claim 1, wherein identifying the estimated downlink resource unit demand for each of the plurality of modulation and coding groups in a beam of the plurality of beams comprises:

receiving link condition data from at least a subset of the plurality of terminals within the beam.

9. The method of claim 1, wherein the dynamically allocating the allocated resource units for each beam comprises:

dynamically changing the per-beam downlink resource unit allocation among beams, wherein the amount allocated for at least a subset of the plurality of beams for the future defined time duration is different from an allocated amount of requested resource units for a prior time duration for the at least the subset of the plurality of beams, the prior time duration substantially equal in length to the future defined time duration.

10. A system for allocating downlink resources in a multi-beam satellite communications network having a plurality of terminals in each of a plurality of beams of a multi-beam satellite, the downlink resources defined in resource units, the system comprising:

a beam estimation module configured to identify an estimated downlink resource unit demand for each of the plurality of beams for a future defined time duration responsive to downlink traffic data for each of the plurality of beams monitored before the future defined time duration;

a modulation and coding group estimation module, in communication with the beam estimation module, and configured to identify an estimated downlink resource unit demand for each of a plurality of modulation and coding groups; and

a resource allocation module, in communication with the beam estimation module and the modulation and coding group estimation module, and configured to;

identify an amount of allocatable resource units for the future defined time duration for the multi-beam satellite communications network;

dynamically allocate, responsive to the estimated downlink resource unit demand for each of the plurality of beams, a subset of the amount of allocatable resource units to each of the plurality of beams to generate a changed per-beam downlink resource unit allocation for the future defined time duration; and

dynamically allocate, responsive to the estimated downlink resource unit demand for each of the plurality of modulation and coding groups in each respective beam, the allocated resource units for each beam among the plurality of modulation and coding groups for the future defined time duration; and

a traffic class estimation module, in communication with the resource allocation module, and configured to identify, within each of the plurality of beams, an estimated downlink resource unit demand for each of a plurality of traffic classes,

wherein the resource allocation module is further configured to allocate the allocated resource units in each of the plurality of modulation and coding groups in each of the plurality of beams among the plurality of traffic classes responsive to the estimated downlink resource unit demand for each of the plurality of traffic classes.

11. The system of claim 10, wherein the beam estimation module is configured to identify the estimated downlink resource unit demand for each of the plurality of beams by receiving a measurement taken on the multi-beam satellite identifying an amount or other rate of traffic directed to each beam.

12. The system of claim 10, wherein the beam estimation module is configured to identify the estimated downlink resource unit demand for each of the plurality of beams by

receiving traffic measurements made by at least a subset of the plurality of terminals in each beam measuring amount of traffic received from the multi-beam satellite.

13. The system of claim 10, wherein at least a portion of the system comprises a ground-based network control center.

14. The system of claim 10, wherein the beam estimation module is configured to identify the estimated downlink resource unit demand for each of the plurality of beams by measuring average queue sizes at the multi-beam satellite attributable to each beam.

15. The system of claim 10, wherein the beam estimation module is further configured to identify the estimated downlink resource unit demand for each of the plurality of beams by calculating a number of dropped packets destined for each downlink beam, the dropped packets occurring at the multi-beam satellite or at a gateway transmitting to the multi-beam satellite.

16. The system of claim 10, wherein a relative allocation among the plurality of traffic classes is different in each beam of the plurality of beams.

17. The system of claim 10, wherein the modulation and coding group estimation module is configured to identify the estimated downlink resource unit demand for each of the plurality of modulation and coding groups in a beam of the plurality of beams by receiving a requested modulation and coding group identification from at least a subset of the plurality of terminals within the beam.

18. A device for allocating downlink resources in a multi-beam satellite communications network having a plurality of terminals in each of a plurality of beams of a multi-beam satellite, the downlink resources defined in resource units, the device comprising:

means for identifying an estimated downlink resource unit demand for each of the plurality of beams for a future defined time duration responsive to downlink traffic data for each of the plurality of beams monitored before the future defined time duration;

means for identifying an amount of allocatable resource units for the future defined time duration for the multi-beam satellite communications network;

means for identifying, in each of the plurality of beams, an estimated downlink resource unit demand for each of a plurality of modulation and coding groups;

means for identifying, in each of the plurality of modulation and coding groups in each of the plurality of beams, an estimated downlink resource unit demand for each of a plurality of traffic classes; and

means for allocating, responsive to the estimated downlink resource unit demand for each of the plurality of beams and the estimated downlink resource unit demand for each of the plurality of modulation and coding groups in each respective beam, a subset of the amount of allocatable resource units to each of the plurality of beams to generate a per-beam downlink resource unit allocation for the future defined time duration and the allocated resource units for each beam among the plurality of modulation and coding groups for the future defined time duration, wherein the allocating comprises allocating the allocated resource units in each of the plurality of modulation and coding groups in each of the plurality of beams among the plurality of traffic classes.

19. The device of claim 18, wherein the device comprises the multi-beam satellite.

20. A satellite communications system for allocating downlink resources in a multi-beam satellite communications network, the downlink resources defined in resource units, the system comprising:

a plurality of terminals in each of a plurality of beams of a multi-beam satellite; and

a resource allocator system in communication via the multi-beam satellite with each of the plurality of terminals in each of the plurality of beams, the resource allocator system configured to;

identify an estimated downlink resource unit demand for each of the plurality of beams for a future defined time duration responsive to downlink traffic data for each of the plurality of beams monitored before the future defined time duration;

identify an amount of allocatable resource units for the future defined time duration for the multi-beam satellite communications network;

identify, for each of a plurality of modulation and coding groups in each of the plurality of beams, an estimated downlink resource unit demand for each of a plurality of traffic classes; and

dynamically allocate, responsive to the estimated downlink resource unit demand for each of the plurality of beams, a subset of the amount of allocatable resource units to each of the plurality of beams to generate a changed per-beam downlink resource unit allocation for the future defined time duration, wherein the allocating comprises allocating the allocated resource units in each of the plurality of modulation and coding groups in each of the plurality of beams among the plurality of traffic classes.