MANAGING DISTRIBUTED ACCESS TO A SHARED MEDIUM

• US 20080279126A1
• Filed: 05/09/2008
• Published: 11/13/2008
• Est. Priority Date: 05/10/2007
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Yonge, Lawrence W. III, Katar, Srinivas, Krishnam, Manjunath, Tahir, Ehab, Lynch, Bradley Robert
• Granted Patent: US 8,493,995 B2
• Time in Patent Office: Days
• US Class Current: 370/294
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 2001/0094 Bus
• CPC Class Codes: H04L 47/826 Involving periods of time

Abstract

Communicating between stations in a network is described. A plurality of stations coordinate according to a distributed protocol to select a first station to transmit over a shared medium. The communication includes transmitting between the first station and a second station over the shared medium during a time period in which stations other than the first and second stations refrain from transmitting over the shared medium. The first station transmits information that grants permission to the second station to transmit during the time period.

Claims

1. A method for communicating between stations in a network, the method comprising:

coordinating among a plurality of the stations according to a distributed protocol to select a first station to transmit over a shared medium; and

transmitting between the first station and a second station over the shared medium during a time period in which stations other than the first and second stations refrain from transmitting over the shared medium, including transmitting from the first station information that grants permission to the second station to transmit during the time period.

2. The method of claim 1, wherein transmitting between the first station and the second station further includes transmitting from the first station information that includes a specified amount of the time period during which the second station is allowed to transmit.

3. The method of claim 1, wherein a specified amount of the time period during which the second station is allowed to transmit is predetermined before the time period begins.

4. The method of claim 3, wherein the specified amount of the time period is stored in each of the stations.

5. The method of claim 4, wherein the specified amount of the time period is stored in a given station when the given station joins the network.

6. The method of claim 3, wherein the specified amount of time is determined as a function of a data rate being used by a station.

7. The method of claim 1, further comprising coordinating among the plurality of stations according to the distributed protocol to select one of the stations to transmit over the shared medium after receiving information over the shared medium from the first station or the second station that indicates that the time period will end.

8. The method of claim 7, wherein the first station or the second station transmits the information that indicates that the time period will end in response to receiving a transmission from the second station or the first station.

9. The method of claim 8, wherein the information that indicates that the time period will end includes acknowledgement information confirming successful transmission of information from the second station or the first station.

10. The method of claim 7, wherein the first station or the second station transmits the information that indicates that the time period will end in response to detecting a potential collision.

11. The method of claim 10, wherein detecting a potential collision comprises receiving a transmission in which at least some data is not correctly received.

12. The method of claim 10, wherein detecting a potential collision comprises not receiving any transmission over the shared medium after a predetermined amount of time.

13. The method of claim 1, wherein the first station transmits the information that grants permission after receiving a request from the second station.

14. The method of claim 13, wherein the request from the second station is transmitted to the first station after at least one transmission from the first station to the second station during the time period.

15. The method of claim 1, further comprising providing a plurality of opportunities for the second station to transmit to the first station during at least a portion of the time period.

16. The method of claim 2, wherein the time period includes time during which the second station is able to transmit acknowledgement information confirming successful transmission of information from the first station to the second station.

17. The method of claim 16, wherein the specified amount of the time period during which the second station has received permission to transmit is larger than the time during which the second station transmits the acknowledgement information.

18. The method of claim 16, wherein the first station transmits the information that grants permission after receiving a request from the second station included in the acknowledgement information.

19. The method of claim 16, wherein the acknowledgement information includes information designating which of multiple segments of information were successfully received by the second station and which of the multiple segments of information should be retransmitted by the first station.

20. The method of claim 1, further comprising transmitting from the second station during the time period in response to receiving the information that grants permission.

21. The method of claim 20, further comprising transmitting from the first station acknowledgement information confirming successful transmission of information from the second station to the first station.

22. The method of claim 21, wherein the acknowledgement information includes information designating which of multiple segments of information were successfully received by the first station and which of the multiple segments of information should be retransmitted by the second station.

23. The method of claim 1, wherein information transmitted from the second station within the specified amount of the time period includes information other than acknowledgement information confirming successful transmission of information from the first station to the second station.

24. The method of claim 23, wherein the information transmitted from the second station within the specified amount of the time period includes a delimiter that precedes a payload, wherein the payload includes the information other than acknowledgement information.

25. The method of claim 24, wherein the delimiter includes acknowledgement information confirming successful transmission of information previously transmitted from the first station to the second station.

26. The method of claim 1, wherein the information that grants permission is included in header information of a transmission from the first station to the second station.

27. The method of claim 1, wherein the first station transmits the information that grants permission after receiving a transmission from the second station that includes an amount of time that is requested.

28. The method of claim 1, wherein information transmitted from the second station to the first station within the specified amount of the time period comprises information used to maintain data flow from the first station to the second station.

29. The method of claim 28, wherein the information transmitted from the second station to the first station within the specified amount of the time period comprises adaptation information used by the first station to prepare a signal to be transmitted to the second station.

30. The method of claim 29, wherein the adaptation information comprises a map that designates a type of modulation that is to be used, respectively, on each of multiple carriers in the signal.

31. The method of claim 1, wherein information transmitted from the second station to the first station within the specified amount of the time period comprises information according to a protocol associated with a connection between the first station and the second station.

32. The method of claim 31, wherein the protocol comprises transmission control protocol (TCP).

33. The method of claim 31, wherein the protocol comprises a voice over internet protocol (VOIP).

34. The method of claim 1, wherein coordinating among the plurality of stations according to the distributed protocol comprises contending according to a carrier sense multiple access (CSMA) protocol.

35. The method of claim 1, wherein coordinating among the plurality of stations according to the distributed protocol comprises selecting a predetermined sequence of time slots to which respective stations are assigned.

36. The method of claim 35, wherein the predetermined sequence of time slots repeats periodically.

37. A system for communicating between stations, the system comprising:

a first station configured to

coordinate among a plurality of the stations according to a distributed protocol to gain access to transmit over a shared medium; and

transmit to a second station over the shared medium during a time period in which stations other than the first and second stations refrain from transmitting over the shared medium, including transmitting information that grants permission to the second station to transmit during the time period; and

the second station configured to, in response to receiving the information that grants permission, transmit to the first station over the shared medium during the time period.

38. A method for communicating between stations in a network, the method comprising

coordinating among a plurality of the stations according to a distributed protocol to select a first station to transmit over a shared medium;

transmitting between the first station and a second station over the shared medium during a time period in which stations other than the first and second stations refrain from transmitting over the shared medium; and

coordinating among the plurality of stations according to the distributed protocol to select one of the stations to transmit over the shared medium after receiving information over the shared medium from the first station or the second station that indicates that the time period will end.

39. The method of claim 38, further comprising transmitting from the first station information that grants permission to the second station to transmit during the time period.

40. The method of claim 38, wherein the first station or the second station transmits the information that indicates that the time period will end in response to receiving a transmission from the second station or the first station.

41. The method of claim 40, wherein the information that indicates that the time period will end includes acknowledgement information confirming successful transmission of information from the second station or the first station.

42. The method of claim 38, wherein the first station or the second station transmits the information that indicates that the time period will end in response to detecting a potential collision.

43. The method of claim 42, wherein detecting a potential collision comprises receiving a transmission in which at least some data is not correctly received.

44. The method of claim 42, wherein detecting a potential collision comprises not receiving any transmission over the shared medium after a predetermined amount of time.

45. The method of claim 38, wherein the information that indicates that the time period will end includes a payload.

46. The method of claim 45, further comprising transmitting acknowledgement information confirming successful transmission of the payload in a transmission sent after the time period has ended.

47. A system for communicating between stations, the system comprising:

a first station configured to

coordinate among a plurality of the stations according to a distributed protocol to gain access to transmit over a shared medium; and

transmit to a second station over the shared medium during a time period in which stations other than the first and second stations refrain from transmitting over the shared medium;

the second station configured to transmit to the first station over the shared medium during the time period; and

a third station configured to coordinate among the plurality of stations according to the distributed protocol to gain access to transmit over the shared medium after receiving information over the shared medium from the first station or the second station that indicates that the time period will end.