Robust inter-radio access technology operations in unlicensed spectrum

• US 9,801,115 B2
• Filed: 09/02/2014
• Issued: 10/24/2017
• Est. Priority Date: 09/04/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Sadek, Ahmed Kamel
• Primary Examiner(s): SMARTH, GERALD A
• Application Number:
  US14/475,033
• Publication Number:
  US 20150063099A1
• Time in Patent Office: 1,148 Days
• CPC Class Codes: H04J 11/0023 Interference mitigation or co-ordination direct sequence spread spectrum [DSSS] systems H04B1/7097; frequency hopping H04B1/713; allocation criteria for ingress interference avoidance H04L5/0062; frequency allocation criteria for requirements on out-of-channel emissions H04L5/0066; arrangements for removing intersymbol interference or baseband equalisers H04L25/03006; peak power aspects in multicarrier modulation H04L27/2614; power management H04W52/00; traffic scheduling H04W72/54, H04W72/541
• CPC Class Codes: H04L 1/0015 characterised by the adaptation strategy
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 16/16 for PBS [Private Base Station] arrangements
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 40/16 based on interference
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

Systems and methods are disclosed for mitigating interference between Radio Access Technologies (RATs) sharing operating spectrum in an unlicensed band of radio frequencies. The mitigation may comprise, for example, identifying an upcoming signal transmission associated with a first RAT, with the signal transmission being scheduled for transmission on the shared operating spectrum during a transmission period. The signal transmission may be classified with respect to a protection status. Based on the protection status, a channel reservation message may be transmitted that is associated with a second RAT to reserve at least a portion of the shared operating spectrum for at least a portion of the transmission period.

Claims

1. A method of communication for mitigating interference between Radio Access Technologies (RATs) sharing operating spectrum in an unlicensed band of radio frequencies, the method comprising:

identifying an upcoming signal transmission associated with a first RAT, wherein the signal transmission is scheduled for transmission on the shared operating spectrum during a transmission period;

classifying the signal transmission with respect to a protection status, wherein the classifying is based on the type of information contained in the signal transmission corresponding to a protected class of transmissions; and

transmitting over the shared operating spectrum, based on the protection status, a channel reservation message associated with a second RAT to reserve at least a portion of the shared operating spectrum for at least a portion of the transmission period.

2. The method of claim 1, wherein:

the first RAT comprises Long Term Evolution (LTE) technology; and

the second RAT comprises Wi-Fi technology.

3. The method of claim 1, wherein the transmitting is performed via a second transceiver operating in accordance with the second RAT, the second transceiver being co-located with a first transceiver operating in accordance with the first RAT to send or receive the identified signal transmission.

4. The method of claim 1, wherein the channel reservation message comprises at least one of a Clear-to-Send-to-Self (CTS2S) message, a Request-to-Send (RTS) message, or a Clear-to-Send (CTS) message defined by the second RAT.

5. The method of claim 1, wherein the channel reservation message is transmitted on a subset of channels representing less than all of the channels defined by the second RAT on the unlicensed band.

6. The method of claim 1, wherein the protected class of transmissions comprises at least one of:

acquisition signals, Random Access Channel (RACH) signals, a last Hybrid Automatic Repeat Request (HARQ) transmission, a Clear Channel Assessment (CCA), a paging message, a time alignment indication, a broadcast signal including a System Information Block (SIB), a mobility and handover indication, or a combination thereof.

7. The method of claim 1, further comprising:

monitoring, on the shared operating spectrum, signaling that is associated with the second RAT;

determining a utilization metric for the second RAT based on the monitored signaling; and

adapting the transmitting of the channel reservation message based on the utilization metric.

8. The method of claim 7, wherein the adapting is further based on one or more expected or historical characteristics of the upcoming signal transmission associated with the first RAT.

9. The method of claim 8, wherein the one or more expected or historical characteristics comprise at least one of:

an expected channel quality for receiving the upcoming signal transmission, a receiver proximity, a success or failure history associated with reception of prior signals, a system acquisition history, a transmission period frequency, or a combination thereof.

10. The method of claim 1, wherein the identifying, classifying, and transmitting are performed by a user device, and wherein:

the identifying comprises monitoring, at the user device, system information transmitted by a base station, and

the classifying comprises determining the protection status based on the system information.

11. The method of claim 10, wherein the protection status is directly indicated by the system information from the base station.

12. The method of claim 10, wherein the protection status is indirectly inferred by the user device from the system information from the base station.

13. The method of claim 1, wherein the identifying, classifying, and transmitting are performed by a base station, and wherein:

the identifying comprises querying, at the base station, scheduler information relating to upcoming signaling, and

the classifying comprises determining the protection status based on the scheduler information.

14. An apparatus for communication for mitigating interference between Radio Access Technologies (RATs) sharing operating spectrum in an unlicensed band of radio frequencies, the apparatus comprising:

a processor configured to identify an upcoming signal transmission associated with a first RAT, wherein the signal transmission is scheduled for transmission on the shared operating spectrum during a transmission period, and to classify the signal transmission with respect to a protection status, wherein the processor is configured to classify the signal transmission based on the type of information contained in the signal transmission corresponding to a protected class of transmissions; and

a transceiver configured to transmit over the shared operating spectrum, based on the protection status, a channel reservation message associated with a second RAT to reserve at least a portion of the shared operating spectrum for at least a portion of the transmission period.

15. The apparatus of claim 14, wherein:

the first RAT comprises Long Term Evolution (LTE) technology; and

the second RAT comprises Wi-Fi technology.

16. The apparatus of claim 14, wherein the transceiver is a second transceiver operating in accordance with the second RAT, the second transceiver being co-located with a first transceiver operating in accordance with the first RAT to send or receive the identified signal transmission.

17. The apparatus of claim 14, wherein the channel reservation message comprises at least one of a Clear-to-Send-to-Self (CTS2S) message, a Request-to-Send (RTS) message, or a Clear-to-Send (CTS) message defined by the second RAT.

18. The apparatus of claim 14, wherein the transceiver is configured to transmit the channel reservation message on a subset of channels representing less than all of the channels defined by the second RAT on the unlicensed band.

19. The apparatus of claim 14, wherein the protected class of transmissions comprises at least one of:

acquisition signals, Random Access Channel (RACH) signals, a last Hybrid Automatic Repeat Request (HARQ) transmission, a Clear Channel Assessment (CCA), a paging message, a time alignment indication, a broadcast signal including a System Information Block (SIB), a mobility and handover indication, or a combination thereof.

20. The apparatus of claim 14, wherein the processor is further configured to:

monitor, on the shared operating spectrum, signaling that is associated with the second RAT;

determine a utilization metric for the second RAT based on the monitored signaling; and

adapt the transmitting of the channel reservation message based on the utilization metric.

21. The apparatus of claim 20, wherein the processor is configured to adapt the transmitting based further on one or more expected or historical characteristics of the upcoming signal transmission associated with the first RAT.

22. The apparatus of claim 21, wherein the one or more expected or historical characteristics comprise at least one of:

an expected channel quality for receiving the upcoming signal transmission, a receiver proximity, a success or failure history associated with reception of prior signals, a system acquisition history, a transmission period frequency, or a combination thereof.

23. The apparatus of claim 14, wherein the processor and the transceiver correspond to a user device, and wherein:

the processor is configured to identify the signal transmission by monitoring, at the user device, system information transmitted by a base station, and

the processor is configured to classify the signal transmission by determining the protection status based on the system information.

24. The apparatus of claim 23, wherein the protection status is directly indicated by the system information from the base station.

25. The apparatus of claim 23, wherein the protection status is indirectly inferred by the user device from the system information from the base station.

26. The apparatus of claim 14, wherein the processor and the transceiver correspond to a base station, and wherein:

the processor is configured to identify the signal transmission by querying, at the base station, scheduler information relating to upcoming signaling, and

the processor is configured to classify the signal transmission by determining the protection status based on the scheduler information.

27. An apparatus for communication for mitigating interference between Radio Access Technologies (RATs) sharing operating spectrum in an unlicensed band of radio frequencies, the apparatus comprising:

means for identifying an upcoming signal transmission associated with a first RAT, wherein the signal transmission is scheduled for transmission on the shared operating spectrum during a transmission period;

means for classifying the signal transmission with respect to a protection status, wherein the means for classifying classifies the signal transmission based on the type of information contained in the signal transmission corresponding to a protected class of transmissions; and

means for transmitting over the shared operating spectrum, based on the protection status, a channel reservation message associated with a second RAT to reserve at least a portion of the shared operating spectrum for at least a portion of the transmission period.

28. A non-transitory computer-readable medium comprising instructions, which, when executed by a processor, cause the processor to perform operations for mitigating interference between Radio Access Technologies (RATs) sharing operating spectrum in an unlicensed band of radio frequencies, the non-transitory computer-readable medium comprising:

instructions for identifying an upcoming signal transmission associated with a first RAT, wherein the signal transmission is scheduled for transmission on the shared operating spectrum during a transmission period;

instructions for classifying the signal transmission with respect to a protection status, wherein the instructions for classifying classify the signal transmission based on the type of information contained in the signal transmission corresponding to a protected class of transmissions; and

instructions for transmitting over the shared operating spectrum, based on the protection status, a channel reservation message associated with a second RAT to reserve at least a portion of the shared operating spectrum for at least a portion of the transmission period.