SUCCESSIVE SCHEDULED REQUESTS FOR TRANSMISSION

• US 20080186861A1
• Filed: 06/29/2007
• Published: 08/07/2008
• Est. Priority Date: 02/06/2007
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Becker, Donald W.
• Granted Patent: US 7,710,876 B2
• Time in Patent Office: Days
• US Class Current: 370/236
• CPC Class Codes: H04B 7/18582 Arrangements for data linking, i.e. for data framing, for error recovery, for multiple access
• CPC Class Codes: H04W 72/1273 of downlink data flows
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 84/06 Airborne or Satellite Networks space-based or airborne stations H04B7/185

Abstract

Methods and apparatuses are presented for conducting communications over a shared communication medium, involving (a) sending an initial request from a first node, the shared communication medium organized to include (i) a request signal space including a plurality of request segments each having a different location within the request signal space and (ii) a scheduled transmission signal space including a plurality of scheduled transmission segments each having a different location within the scheduled transmission signal space, the initial request sent in an initial request segment, (b) obtaining a request assignment associating the initial request with at least one follow-up request segment, (c) from the first node, sending a follow-up request in the at least one follow-up request segment, (d) obtaining a scheduled transmission assignment specifying a scheduled transmission segment, and (e) from the first node, sending a data transmission in the scheduled transmission segment.

Claims

1. A method for conducting communications over a shared communication medium involving a plurality of nodes, the method comprising:

(a) sending an initial request from a first node in the plurality of nodes, the shared communication medium organized to include a request signal space and a scheduled transmission signal space, the request signal space including a plurality of request segments each having a different location within the request signal space, the scheduled transmission signal space including a plurality of scheduled transmission segments each having a different location within the scheduled transmission signal space, the initial request sent in an initial request segment that is one of the plurality of request segments;

(b) obtaining a request assignment associating the initial request with at least one follow-up request segment, the request assignment taking into account location of the initial request within the request signal space;

(c) from the first node, sending a follow-up request in the at least one follow-up request segment;

(d) obtaining a scheduled transmission assignment specifying a scheduled transmission segment selected from the plurality of scheduled transmission segments, the scheduled transmission assignment taking into account location of the follow-up request within the request signal space; and

(e) from the first node, sending a data transmission in the scheduled transmission segment.

2. The method of claim 1 wherein the follow-up request is used to resolve a collision of multiple requests in the initial request segment.

3. The method of claim 2 wherein the first node and a competing node each randomly selects one of the at least one follow-up request segment and sends a follow-up request in the randomly selected follow-up request segment.

4. The method of claim 3 wherein the first node randomly selects a different follow-up request segment than the competing node, and the collision is resolved.

5. The method of claim 4 wherein the first node receives a scheduled transmission assignment associating the follow-up request sent from the first node with a scheduled transmission request, and the competing node separately receives another scheduled transmission assignment associating the follow-up request sent from the competing node with another scheduled transmission request.

6. The method of claim 3 wherein the first node randomly selects the same follow-up request segment as the competing node, and the collision is not resolved.

7. The method of claim 6 wherein the first node and the competing node attempt again to resolve the collision, by obtaining a new assignment of at least one follow-up request segment, wherein the first node and the competing node each randomly selects one of the at least one follow-up request segment in the new assignment and sends a follow-up request in the randomly selected follow-up request segment.

8. The method of claim 2 wherein the follow-up request is used to resolve a collision involving more than two nodes.

9. The method of claim 1 wherein the follow-up request comprises additional information to supplement the initial request.

10. The method of claim 9 wherein the additional information specifies a service type for the initial request.

11. A method for conducting communications over a shared communication medium involving a plurality of nodes including a first node and a second node, the method comprising:

(a) at the second node, receiving an initial request from the first node, the shared communication medium organized to include a request signal space and a scheduled transmission signal space, the request signal space including a plurality of request segments each having a different location within the request signal space, the scheduled transmission signal space including a plurality of scheduled transmission segments each having a different location within the scheduled transmission signal space, the initial request sent in an initial request segment that is one of the plurality of request segments;

(b) at the second node, making a request assignment associating the initial request with at least one follow-up request segment, the request assignment taking into account location of the initial request within the request signal space, and sending a corresponding request assignment message;

(c) at the second node, receiving a follow-up request from the first node in the at least one follow-up request segment;

(d) at the second node, making a scheduled transmission assignment specifying a scheduled transmission segment selected from the plurality of scheduled transmission segments, the scheduled transmission assignment taking into account location of the follow-up request within the request signal space, and sending a corresponding scheduled transmission assignment message;

(e) at the second node, receiving a data transmission from the first node in the scheduled transmission segment.

12. An apparatus for conducting communications over a shared communication medium involving a plurality of nodes, comprising:

(a) a first node capable of sending an initial request over the shared communication medium, the shared communication medium organized to include a request signal space and a scheduled transmission signal space, the request signal space including a plurality of request segments each having a different location within the request signal space, the scheduled transmission signal space including a plurality of scheduled transmission segments each having a different location within the scheduled transmission signal space, the first node capable of sending the initial request in an initial request segment that is one of the plurality of request segments;

(b) wherein the first node is capable of obtaining a request assignment associating the initial request at least one follow-up request segment, the request assignment taking into account location of the initial request within the request signal space;

(c) wherein the first node is capable of sending a follow-up request in the at least one follow-up request segment;

(d) wherein the first node is capable of obtaining a schedule transmission assignment specifying a scheduled transmission segment selected from the plurality of scheduled transmission segments, the scheduled transmission assignment taking into account location of the follow-up request within the request signal space; and

(e) wherein the first node is capable of sending a data transmission in the scheduled transmission segment.

13. The apparatus of claim 12 wherein the follow-up request is used to resolve a collision of multiple requests in the initial request segment.

14. The apparatus of claim 13 wherein the first node and a competing node each randomly selects one of the at least one follow-up request segment and sends a follow-up request in the randomly selected follow-up request segment.

15. The apparatus of claim 14 wherein the first node randomly selects a different follow-up request segment than the competing node, and the collision is resolved.

16. The apparatus of claim 15 wherein the first node receives a scheduled transmission assignment associating the follow-up request sent from the first node with a scheduled transmission request, and the competing node separately receives another scheduled transmission assignment associating the follow-up request sent from the competing node with another scheduled transmission request.

17. The method of claim 14 wherein the first node randomly selects the same follow-up request segment as the competing node, and the collision is not resolved.

18. The apparatus of claim 17 wherein the first node and the competing node attempt again to resolve the collision, by obtaining a new assignment of at least one follow-up request segment, wherein the first node and the competing node each randomly selects one of the at least one follow-up request segment in the new assignment and sends a follow-up request in the randomly selected follow-up request segment.

19. The apparatus of claim 13 wherein the follow-up request is used to resolve a collision involving more than two nodes.

20. The apparatus of claim 12 wherein the follow-up request comprises additional information to supplement the initial request.

21. The apparatus of claim 20 wherein the additional information specifies a service type for the initial request.

22. An apparatus for conducting communications over a shared communication medium involving a plurality of nodes, comprising:

(a) a second node capable of receiving an initial request from a first node, the shared communication medium organized to include a request signal space and a scheduled transmission signal space, the request signal space including a plurality of request segments each having a different location within the request signal space, the scheduled transmission signal space including a plurality of scheduled transmission segments each having a different location within the scheduled transmission signal space, the second node capable of receiving the initial request in an initial request segment that is one of the plurality of request segments;

(b) wherein the second node is capable of making a request assignment associating the initial request with at least one follow-up request segment, the request assignment taking into account location of the initial request within the request signal space, and sending a corresponding assignment message;

(c) wherein the second node is capable of receiving a follow-up request from the first node in the at least one follow-up request segment;

(d) wherein the second node is capable of making a scheduled transmission assignment specifying a scheduled transmission segment selected from the plurality of scheduled transmission assignments, the scheduled transmission assignment taking into account location of the follow-up request within the request signal space; and

(e) wherein the second node is capable of receiving a data transmission from the first node in the scheduled transmission segment.