METHODS AND APPARATUS FOR ADAPTING TRANSMITTER CONFIGURATION FOR EFFICIENT CONCURRENT TRANSMISSION AND RADAR DETECTION THROUGH ADAPTIVE SELF-INTERFERENCE CANCELLATION

• US 20150296413A1
• Filed: 08/12/2014
• Published: 10/15/2015
• Est. Priority Date: 04/11/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: SADEK, Ahmed Kamel, Grob, Matthew Stuart
• Granted Patent: US 9,503,134 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 1/1027 assessing signal quality or detecting noise/interference for the received signal
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04L 1/00 Arrangements for detecting or preventing errors in the information received correcting synchronisation H04L7/00
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks

Abstract

Certain aspects of the present disclosure relate to adapting transmitter configuration for efficient concurrent primary user detection through adaptive self-interference cancellation. A wireless transmitting device may schedule a transmission in a shared spectrum. The device may scan at least a portion of the shared spectrum during the transmission to receive a signal. Interference caused by the transmission may he cancelled from the received signal using self-interference cancellation circuitry. The device may determine whether the received signal indicates usage by a primary user of the shared spectrum. In an aspect, the transmission may be a SISO transmission. In another aspect, carrier aggregation may be used for the transmission and a potential carrier may be subject to primary user detection. The device may determine a self-interference cancellation complexity for a combination of carriers including the potential carrier, and may select one or more carriers for aggregation based on the self-interference cancellation complexity.

Claims

1. A method for wireless communication, the method comprising:

scheduling a transmission in a shared spectrum;

scanning at least a portion of the shared spectrum during the transmission to obtain a received signal;

cancelling, at least partially from the received signal, an interference caused by the transmission on the received signal, wherein the cancelling includes processing the received signal using a self-interference cancellation circuitry; and

determining whether a signal resulting from the cancelling indicates usage by a primary user of the shared spectrum.

2. The method of claim 1, wherein the transmission is a single-input single-output (SISO) transmission and scheduling the transmission comprises scheduling the SISO transmission between multiple-input multiple-output (MIMO) transmissions.

3. The method of claim 2, further comprising:

determining that a serving load allows scheduling a transmission gap between the MIMO transmissions, wherein the transmission gap has no scheduled transmission; and

bypassing the processing of the received signal by the self-interference cancellation circuitry during the transmission gap.

4. The method of claim 2, wherein the scheduling is based on a utility function of one or more of a serving load of a transmitting device, throughput of the SISO transmission, and power consumption of the self-interference cancellation circuitry.

5. The method of claim 2, wherein the scheduling includes selecting a user equipment to receive the SISO transmission based on feedback from the user equipment, wherein the feedback indicates that the user equipment is unable to receive a MIMO transmission.

6. The method of claim 2, wherein the scheduling includes selecting a user equipment for the SISO transmission based on a fairness criteria for allocating the SISO transmission and the MIMO transmissions among a plurality of user equipments.

7. The method of claim 2, further comprising selecting from a plurality of antennas, an antenna for the SISO transmission based on spatial characteristics of a recipient of the SISO transmission.

8. The method of claim 7, further comprising storing self-interference cancellation circuitry parameters for the plurality of antennas, wherein the cancelling comprises processing the received signal using the self-interference cancellation circuitry parameters for the selected antenna.

9. The method of claim 1, wherein the scheduling of the transmission includes:

determining that carrier aggregation is to be used for the transmission;

determining that a potential carrier for the carrier aggregation is subject to usage by the primary user;

determining a self-interference cancellation complexity for a potential combination of carriers including the potential carrier; and

selecting one or more carriers for the carrier aggregation based at least in part on the self-interference cancellation complexity.

10. The method of claim 9, further comprising assigning a weight to the potential combination of carriers based on the self-interference cancellation complexity, wherein selecting one or more carriers for the carrier aggregation is further based on weights based on channel interference and link quality of users.

11. The method of claim 10, wherein the weight assigned to the potential combination of carriers based on the self-interference cancellation complexity varies based on a transmission load.

12. The method of claim 10, wherein the weight assigned to the potential combination of carriers based on the self-interference cancellation complexity depends on a loss in system capacity associated with scheduling transmission gaps for detecting the primary user.

13. The method of claim 9, wherein determining that the potential carrier for the carrier aggregation is subject to usage by the primary user comprises determining that the potential carrier is in a channel subject to radar detection.

14. An apparatus for wireless communication, the apparatus comprising:

means for scheduling a transmission in a shared spectrum;

means for scanning at least a portion of the shared spectrum during the transmission to obtain a received signal;

means for cancelling, at least partially from the received signal, an interference caused by the transmission on the received signal, wherein the cancelling includes processing the received signal using a self-interference cancellation circuitry; and

means for determining whether the received a signal resulting from the cancelling indicates usage by a primary user of the shared spectrum.

15. The apparatus of claim 14, wherein the transmission is a single-input single-output (SISO) transmission, wherein the means for scheduling is configured to schedule the SISO transmission between multiple-input multiple-output (MIMO) transmissions.

16. The apparatus of claim 15, further comprising:

means for determining that a serving load allows scheduling a transmission gap between the MIMO transmissions, wherein the transmission gap has no scheduled transmission; and

means for bypassing the processing of the received signal by the self-interference cancellation circuitry during the transmission gap.

17. The apparatus of claim 14, further comprising:

means for determining that carrier aggregation is to be used for a transmission;

means for determining that a potential carrier for the carrier aggregation is subject to usage by the primary user;

means for determining a self-interference cancellation complexity for a potential combination of carriers including the potential carrier; and

means for selecting one or more carriers for the carrier aggregation based at least in part on the self-interference cancellation complexity.

18. A non-transitory computer readable medium storing computer executable code, comprising instructions for:

scheduling a transmission in a shared spectrum;

scanning at least a portion of the shared spectrum during the transmission to obtain a received signal;

cancelling, at least partially from the received signal, an interference caused by the transmission on the received signal, wherein the cancelling includes processing the received signal using a self-interference cancellation circuitry; and

determining whether a signal resulting from the cancelling indicates usage by a primary user of the shared spectrum.

19. The computer readable medium of claim 18, wherein the transmission is a single-input single-output (SISO) transmission and wherein the instructions for scheduling the transmission comprise instructions for scheduling the SISO transmission between multiple-input multiple-output (MIMO) transmissions.

20. The computer readable medium of claim 18, further comprising instructions for:

determining that a serving load allows scheduling a transmission gap between the MIMO transmissions, wherein the transmission gap has no scheduled transmission; and

bypassing the processing of the received signal by the self-interference cancellation circuitry during the transmission gap.

21. The computer readable medium of claim 18, further comprising instructions for:

determining that carrier aggregation is to be used for the transmission;

determining that a potential carrier for the carrier aggregation is subject to usage by the primary user;

determining a self-interference cancellation complexity for a potential combination of carriers including the potential carrier; and

selecting one or more carriers for the carrier aggregation based at least in part on the self-interference cancellation complexity.

22. An apparatus comprising:

a scheduling component configured to schedule a transmission in a shared spectrum;

a receiver configured to scan at least a portion of the shared spectrum during the transmission to obtain a received signal;

a self-interference cancellation circuit configured to cancel, at least partially from the received signal, an interference caused by the transmission on the received signal; and

a processor configured to determine whether a signal resulting from the cancelling indicates usage by a primary user of the shared spectrum.

23. The apparatus of claim 22, wherein the scheduling component is configured to schedule the transmission as a single-input single-output (SISO) transmission between multiple-input multiple-output (MIMO) transmissions.

24. The apparatus of claim 23, wherein the scheduling component is further configured to determine that a serving load allows scheduling a transmission gap between the MIMO transmissions, wherein the transmission gap has no scheduled transmission;

and bypass the self-interference cancellation circuit during the transmission gap.

25. The apparatus of claim 23, wherein the scheduling component is configured to schedule the transmission based on a utility function of one or more of a serving load of a transmitting device, throughput of the SISO transmission, and power consumption of the self-interference cancellation circuit.

26. The apparatus of claim 23, wherein the self-interference cancellation circuit is further configured to process the received signal using self-interference cancellation circuitry parameters for an antenna selected for the transmission based on spatial characteristics of a recipient of the SISO transmission.

27. The apparatus of claim 22, wherein the processor is further configured to:

determine that carrier aggregation is to be used for a transmission;

determine that a potential carrier for the carrier aggregation is subject to usage by the primary user;

determine a self-interference cancellation complexity for a potential combination of carriers including the potential carrier; and

select one or more carriers for the carrier aggregation based at least in part on the self-interference cancellation complexity.

28. The apparatus of claim 22, further comprising a transmitter communicatively coupled to the self-interference cancellation circuit.

29. The apparatus of claim 27, wherein the processor is further configured to assign a weight to the potential combination of carriers based on the self-interference cancellation complexity, wherein the selection of the one or more carriers for the carrier aggregation is further based on weights based on channel interference and link quality of users.

30. The apparatus of claim 27, wherein the processor is further configured to determine that the potential carrier for the carrier aggregation is subject to usage by the primary user by determining that the potential carrier is in a channel subject to radar detection.