Channel reuse in communication systems

• US 8,862,069 B2
• Filed: 06/20/2013
• Issued: 10/14/2014
• Est. Priority Date: 07/20/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Yonge, Lawrence Winston III, Katar, Srinivas, Krishnam, Manjunath Anandarama
• Primary Examiner(s): Nguyen, Duc M
• Application Number:
  US13/923,153
• Publication Number:
  US 20130279621A1
• Time in Patent Office: 481 Days
• Field of Search: 455/67.11, 455/522, 455/447, 370/230, 370/235, 370/445
• US Class Current: 455/67.11
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 28/0231 based on communication conditions dynamic wireless traffic scheduling definition based on channel quality criteria H04W72/54
• CPC Class Codes: H04W 52/245 taking into account received signal strength
• CPC Class Codes: H04W 56/0095 estimated based on signal strength
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]

Abstract

A method includes determining a signal strength value for a first received signal received from a first station in a first network. The first received signal is received in the first network through a shared communication medium that is shared with a second network. The method includes receiving an indicator of a signal strength value determined for a second received signal from a second station in the second network. Based on the signal strength value for the first received signal and based on the indicator of the signal strength value determined for the second received signal, a detection threshold is selected such that, in response to a third received signal having a signal strength in excess of the detection threshold, the third received signal is processed according to a protocol of the first network and is not processed according to a protocol of the second network.

Claims

1. A method of communicating over a shared communication medium shared by a first network and a second network, the method comprising:

receiving, at a first station in the first network, a first signal associated with the first network;

determining a first signal strength value for the first signal based at least in part on at least one of a portion of a detected preamble of the first signal and a portion of a detected frame control of the first signal;

receiving, from a second station in the second network, a second signal strength value for a second signal associated with the second network; and

determining a detection threshold based at least in part on the first signal strength value and the second signal strength value, the detection threshold determined such that a third received signal having a third signal strength value greater than the detection threshold is processed according to a first protocol of the first network and is not processed according to a second protocol of the second network.

2. The method of claim 1, further comprising:

excluding, based at least in part on the third signal strength value for the third received signal being lower than the detection threshold, the third received signal from further processing; and

proceeding with a contention process among the first station and other stations in the first network.

3. The method of claim 1, further comprising:

suspending, based at least in part on the third signal strength value for the third received signal being in excess of the detection threshold, a contention process among the first station and other stations in the first network.

4. The method of claim 1, wherein determining the first signal strength value for the first signal comprises determining an automatic gain control setting used for detecting the first signal.

5. The method of claim 1, wherein determining the first signal strength value for the first signal comprises determining at least one of a correlation between different portions of the first signal and a correlation between a portion of the first signal and a stored symbol.

6. The method of claim 1, further comprising:

transmitting a pending transmission from the first station in the first network to a first destination station based at least in part on a determination by the first station whether a second destination station in the second network receiving an ongoing transmission is affected by the pending transmission.

7. The method of claim 1, further comprising:

disabling communication among the first station and other stations in the first network, during a time when there are communications between the first station and the second station through the shared communication medium.

8. A method of communicating over a shared communication medium, the method comprising:

receiving, at a first station in a network, first signals from other stations in the network through the shared communication medium;

determining, by the first station, signal strength values for the first signals based at least in part on at least one of a portion of a detected preamble of the first signals and a portion of a detected frame control of the first signals;

determining, by the first station, a detection threshold such that the first signals received from a first subset of the other stations have signal strength values in excess of the detection threshold and such that the first received from a second subset of the other stations have signal strength values below the detection threshold;

receiving, after determining the detection threshold and at the first station, a second signal from one of the other stations in the network through the shared communication medium;

accepting and processing, by the first station based at least in part on the second signal being in excess of the detection threshold, the second signal from the first subset of the other stations in the network; and

ignoring, by the first station based at least in part on receiving a third signal that is below the detection threshold, the third signal from the second subset of the other stations.

9. The method of claim 8, further comprising, maintaining, by the first station, the signal strength values for the first subset and second subset of the other stations.

10. The method of claim 8, wherein determining, by the first station, signal strength values for the first signals from the other stations in the network comprises determining an automatic gain control setting used for detecting the first signals.

11. The method of claim 8, wherein determining signal strength values for the first signals from the other stations in the network comprises determining at least one of a correlation between different portions of the first signals and a correlation between a portion of the first signals and a stored symbol.

12. The method of claim 8, further comprising after determining the detection threshold:

transmitting a pending transmission from the first station in the network to a first destination station of the first subset of the other stations based at least in part on a determination by the first station whether a second destination station of the second subset of the other stations is affected by the pending transmission.

13. An apparatus comprising:

a processor configured to execute computer usable program code, wherein based at least in part on execution of the computer usable program code, the processor is configured to;

receive, at a first station in a first network, a first signal associated with the first network, wherein a shared communication medium is shared by the first network and a second network;

determine a first signal strength value for the first signal based at least in part on at least one of a portion of a detected preamble of the first signal and a portion of a detected frame control of the first signal;

receive, from a second station in the second network, a second signal strength value for a second signal associated with the second network; and

determine a detection threshold based at least in part on the first signal strength value and the second signal strength value, the detection threshold determined such that a third received signal having a third signal strength value greater than the detection threshold is processed according to a first protocol of the first network and is not processed according to a second protocol of the second network.

14. The apparatus of claim 13, wherein based at least in part on execution of the computer usable program code, the processor is configured to:

exclude, based at least in part on the third signal strength value for the third received signal being lower than the detection threshold, the third received signal from further processing; and

proceed with a contention process among the first station and other stations in the first network.

15. The apparatus of claim 13, wherein based at least in part on execution of the computer usable program code, the processor is configured to:

suspend, based at least in part on the third signal strength value for the third received signal being in excess of the detection threshold, a contention process among the first station and other stations in the first network.

16. The apparatus of claim 13, wherein the processor configured to determine the first signal strength value for the first signal comprises the processor configured to determine an automatic gain control setting used for detecting the first signal.

17. The apparatus of claim 13, wherein the processor configured to determine the first signal strength value for the first signal comprises the processor configured to determine at least one of a correlation between different portions of the first signal and a correlation between a portion of the first signal and a stored symbol.

18. The apparatus of claim 13, wherein based at least in part on execution of the computer usable program code, the processor is configured to:

transmit a pending transmission from the first station in the first network to a first destination station based at least in part on a determination by the first station whether a second destination station in the second network that is to receive an ongoing transmission is affected by the pending transmission.

19. The apparatus of claim 13, wherein based at least in part on execution of the computer usable program code, the processor is configured to:

disable communication among the first station and other stations in the first network, during a time when there are communications between the first station and the second station through the shared communication medium.

20. A station comprising:

a processor configured to execute computer usable program code, wherein based at least in part on execution of the computer usable program code, the processor is configured to;

receive first signals from other stations in a network through a shared communication medium;

determine signal strength values for the first signals based at least in part on at least one of a portion of a detected preamble of the first signals and a portion of a detected frame control of the first signals;

determine a detection threshold such that the first signals received from a first subset of the other stations have signal strength values in excess of the detection threshold and such that the first signals received from a second subset of the other stations have signal strength values below the detection threshold;

receive, after determination of the detection threshold, a second signal from one of the other stations in the network through the shared communication medium;

accept and process, based at least in part on the second signal being in excess of the detection threshold, the second signal from the first subset of the other stations in the network; and

ignore, based at least in part on receipt of a third signal that is below the detection threshold, the third signal from the second subset of the other stations.

21. The station of claim 20, wherein based at least in part on execution of the computer usable program code, the processor is configured to:

maintain the signal strength values for the first subset and second subset of the other stations.

22. The station of claim 20, wherein the processor configured to determine signal strength values for the first signals from the other stations in the network comprises the processor configured to determine an automatic gain control setting used for detecting the first signals.

23. The station of claim 20, wherein the processor configured to determine signal strength values for the first signals from the other stations in the network comprises the processor configured to determine at least one of a correlation between different portions of the first signals and a correlation between a portion of the first signals and a stored symbol.

24. The station of claim 20, wherein based at least in part on execution of the computer usable program code, the processor is configured to:

transmit, after determination of the detection threshold, a pending transmission from the station in the network to a first destination station of the first subset of the other stations based at least in part on a determination by the station whether a second destination station of the second subset of the other stations is affected by the pending transmission.