DYNAMIC REVERSE LINK RETRANSMISSION TIMELINES IN SATELLITE COMMUNICATION SYSTEMS

• US 20180083694A1
• Filed: 09/21/2016
• Published: 03/22/2018
• Est. Priority Date: 09/21/2016
• Status: Active Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Rajagopalan, Venkatraman, Damnjanovic, Jelena, Wu, Qiang
• Granted Patent: US 10,263,691 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18519 Operations control, administration or maintenance
• CPC Class Codes: H04B 7/18541 for handover of resources
• CPC Class Codes: H04B 7/195 Non-synchronous stations
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1816 with retransmission of the same, encoded, message
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04W 56/005 compensating for timing error by adjustment in the receiver
• CPC Class Codes: H04W 56/0065 using measurement of signal travel time

Abstract

A method and apparatus for operating a satellite access network (SAN) of a satellite communication system to schedule communications with a user terminal. In some aspects, the SAN may provision a communication frame, for the user terminal, into a number of forward-link (FL) subframes and a different number of reverse-link (RL) subframes. The SAN then transmits the FL subframes to the user terminal via a forward link of the satellite communication system, and subsequently receives the RL subframes from the user terminal via a reverse link of the satellite communication system.

Claims

1. A method of operating a satellite access network (SAN) of a satellite communication system, the method comprising:

receiving reverse-link (RL) data from a user terminal via a satellite of the satellite communication system;

requesting a retransmission, from the user terminal, of at least a portion of the RL data; and

dynamically configuring a timeline for processing the retransmission based at least in part on changes in an amount of feeder-link delay between the SAN and the satellite.

2. The method of claim 1, wherein the timeline includes a timing of a retransmission request, sent by the SAN to the user terminal, for the portion of RL data.

3. The method of claim 2, wherein the timeline is used by the user terminal to synchronize the retransmission request with a hybrid automatic repeat request (HARQ) process associated with the portion of RL data.

4. The method of claim 1, wherein the dynamically configuring comprises:

detecting a change in the feeder-link delay; and

adjusting the timeline for processing the retransmission based on the detected change in feeder-link delay.

5. The method of claim 1, wherein the dynamically configuring comprises:

communicating, to the user terminal, information pertaining to the timeline for processing the retransmission.

6. The method of claim 5, wherein the information includes an amount of delay to be implemented by the user terminal between the transmission and retransmission of the portion of RL data.

7. The method of claim 5, wherein the information is provided in an RL grant message communicated to the user terminal.

8. The method of claim 5, wherein the information is provided in a radio resource control (RRC) configuration message communicated to the user terminal during an inter-beam handover.

9. The method of claim 5, wherein the information includes a HARQ process identifier associated with the portion of RL data.

10. The method of claim 9, wherein the information is provided in a retransmission request communicated to the user terminal for the corresponding portion of RL data.

11. A satellite access network (SAN) comprising:

one or more processors; and

a memory configured to store instructions that, when executed by the one or more processors, cause the SAN to;

receive reverse-link (RL) data from a user terminal via a satellite of a satellite communication system;

request a retransmission, from the user terminal, of at least a portion of the RL data; and

dynamically configure a timeline for processing the retransmission based at least in part on changes in an amount of feeder-link delay between the SAN and the satellite.

12. The satellite access network of claim 11, wherein the timeline includes a timing of a retransmission request, sent by the SAN to the user terminal, for the portion of RL data.

13. The satellite access network of claim 12, wherein the timeline is used by the user terminal to synchronize the retransmission request with a hybrid automatic repeat request (HARQ) process associated with the portion of RL data.

14. The satellite access network of claim 11, wherein execution of the instructions to dynamically configure the timeline causes the SAN to:

detect a change in the feeder-link delay; and

adjust the timeline for processing the retransmission based on the detected change in feeder-link delay.

15. The satellite access network of claim 11, wherein execution of the instructions to dynamically configure the timeline causes the SAN to:

communicate, to the user terminal, information pertaining to the timeline for processing the retransmission.

16. The satellite access network of claim 15, wherein the information includes an amount of delay to be implemented by the user terminal between the transmission and retransmission of the portion of RL data, and wherein the information is provided in at least one of an RL grant message communicated to the user terminal or a radio resource control (RRC) configuration message communicated to the user terminal during an inter-beam handover.

17. The satellite access network of claim 15, wherein the information includes a HARQ process identifier associated with the portion of RL data, and wherein the information is provided in a retransmission request communicated to the user terminal for the corresponding portion of RL data.

18. A satellite access network (SAN) comprising:

means for receiving reverse-link (RL) data from a user terminal via a satellite of a satellite communication system;

means for requesting a retransmission, from the user terminal, of at least a portion of the RL data; and

means for dynamically configuring a timeline for processing the retransmission based at least in part on changes in an amount of feeder-link delay between the SAN and the satellite.

19. The satellite access network of claim 18, wherein the timeline includes a timing of a retransmission request, sent by the SAN to the user terminal, for the portion of RL data.

20. The satellite access network of claim 19, wherein the timeline is used by the user terminal to synchronize the retransmission request with a hybrid automatic repeat request (HARQ) process associated with the portion of RL data.

21. The satellite access network of claim 18, wherein the means for dynamically configuring comprises:

means for detecting a change in the feeder-link delay; and

means for adjusting the timeline for processing the retransmission based on the detected change in feeder-link delay.

22. The satellite access network of claim 18, wherein the means for dynamically configuring comprises:

means for communicating, to the user terminal, information pertaining to the timeline for processing the retransmission.

23. The satellite access network of claim 22, wherein the information includes an amount of delay to be implemented by the user terminal between the transmission and retransmission of the portion of RL data, and wherein the information is provided in at least one of an RL grant message communicated to the user terminal or a radio resource control (RRC) configuration message communicated to the user terminal during an inter-beam handover.

24. The satellite access network of claim 22, wherein the information includes a HARQ process identifier associated with the portion of RL data, and wherein the information is provided in a retransmission request communicated to the user terminal for the corresponding portion of RL data.

25. A non-transitory computer-readable medium storing instructions that, when executed by one or more processors of a satellite access network (SAN), cause the SAN to perform operations comprising:

receiving reverse-link (RL) data from a user terminal via a satellite of a satellite communication system;

requesting a retransmission, from the user terminal, of at least a portion of the RL data; and

dynamically configuring a timeline for processing the retransmission based at least in part on varying amounts of feeder-link delay.

26. The non-transitory computer-readable medium of claim 25, wherein the timeline includes a timing of a retransmission request, sent by the SAN to the user terminal, for the portion of RL data, and wherein the timeline is used by the user terminal to synchronize the retransmission request with a hybrid automatic repeat request (HARQ) process associated with the portion of RL data.

27. The non-transitory computer-readable medium of claim 25, wherein execution of the instructions for dynamically configuring the timeline causes the SAN to:

detect a change in the feeder-link delay; and

adjust the timeline for processing the retransmission based on the detected change in feeder-link delay.

28. The non-transitory computer-readable medium of claim 25, wherein execution of the instructions for dynamically configuring the timeline causes the SAN to:

communicate, to the user terminal, information pertaining to the timeline for processing the retransmission.

29. The non-transitory computer-readable medium of claim 28, wherein the information includes an amount of delay to be implemented by the user terminal between the transmission and retransmission of the portion of RL data, and wherein the information is provided in at least one of an RL grant message communicated to the user terminal or a radio resource control (RRC) configuration message communicated to the user terminal during an inter-beam handover.

30. The non-transitory computer-readable medium of claim 28, wherein the information includes a HARQ process identifier associated with the portion of RL data, and wherein the information is provided in a retransmission request communicated to the user terminal for the corresponding portion of RL data.