CHANNEL AND INTERFERENCE MEASUREMENT IN LTE/LTE-A NETWORKS INCLUDING UNLICENSED SPECTRUM

• US 20150181453A1
• Filed: 11/24/2014
• Published: 06/25/2015
• Est. Priority Date: 12/19/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Chen, Wanshi, Malladi, Durga Prasad, Luo, Tao, Gaal, Peter, Xu, Hao, Ji, Tingfang, Yerramalli, Srinivas, Bhushan, Naga, Damnjanovic, Aleksandar, Wei, Yongbin
• Granted Patent: US 9,681,325 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

Channel and interference measurement in long term evolution (LTE)/LTE-Advanced (LTE-A) networks including unlicensed spectrum is discussed in which a user equipment (UE) detects a reference signal from a serving base station over a carrier of a shared spectrum for measurement. The reference signal may be a channel usage beacon signal (CUBS) transmitted by the serving base station prior to transmission or may be a specific channel state information (CSI) reference signal transmitted in the first subframe of a transmission frame. The UE generates a fast CSI feedback report based on the measured reference signal and transmits it to the serving base station. The fast CSI feedback report is received quickly enough by the serving base station such that the base station may apply the CSI feedback to additional transmissions in subsequent subframes within the same transmission frame.

Claims

1. A method of wireless communication, comprising:

detecting, by a user equipment (UE), a reference signal from a serving base station over a carrier of shared spectrum;

measuring, by the UE, the reference signal;

generating, by the UE, a fast channel station information (CSI) feedback report based on the measured reference signal; and

transmitting, by the UE, the fast CSI feedback report to the serving base station.

2. The method of claim 1, wherein the detecting includes:

detecting the reference signal in a first subframe of a transmission frame of the serving base station.

3. The method of claim 1, wherein the reference signal includes a channel usage beacon signal (CUBS) from the serving base station.

4. The method of claim 1, wherein the generating the fast CSI feedback report includes one or more of:

reducing a bitwidth of a standard CSI feedback report for the fast CSI feedback report;

selecting a subset of CSI reporting types from a plurality of available CSI reporting types for including in the fast CSI feedback report;

selecting a subset of CSI processes from a plurality of available CSI processes for including in the fast CSI feedback report;

reducing CSI measurement processing of the reference signal measuring for the fast CSI feedback report; and

reducing a transmission duration of CSI reporting for the fast CSI feedback report.

5. The method of claim 1, further including:

generating a non-fast CSI feedback report based, at least in part, on the reference signal; and

transmitting the non-fast CSI feedback report at a later interval from the fast CSI feedback report.

6. The method of claim 5, wherein the non-fast CSI feedback report includes one of:

a standard CSI feedback report;

or

a refined CSI feedback report, wherein the refined CSI feedback report is based on one of;

additional channel information or interference information.

7. The method of claim 1, wherein the fast CSI feedback report is transmitted in an uplink subframe following a downlink subframe from which the reference signal is detected.

8. The method of claim 1, further including:

receiving a fast CSI reporting indicator from the serving base station, wherein the fast CSI reporting indicator indicators to the UE whether to enable or disable fast CSI reporting.

9. The method of claim 8, wherein, in response to receiving the fast CSI reporting indicator indicating to disable fast CSI reporting, the UE disables each one or more of the measuring, the generating, and the transmitting occurring after the fast CSI reporting indicator is received.

10. The method of claim 1, wherein the transmitting the fast CSI feedback report includes:

determining, by the UE, an earliest available uplink carrier of a plurality of uplink carriers; and

transmitting the fast CSI feedback report on the determined earliest available uplink carrier.

11. The method of claim 1, wherein the shared spectrum is at least one of an unlicensed spectrum or a spectrum allowing sharing among a plurality of operators.

12. An apparatus for wireless communication, comprising:

means for detecting, by a user equipment (UE), a reference signal from a serving base station over a carrier of shared spectrum;

means for measuring, by the UE, the reference signal;

means for generating, by the UE, a fast channel station information (CSI) feedback report based on the measured reference signal; and

means for transmitting, by the UE, the fast CSI feedback report to the serving base station.

13. The apparatus of claim 12, wherein the means for detecting includes:

means for detecting the reference signal in a first subframe of a transmission frame of the serving base station.

14. The apparatus of claim 12, wherein the means for generating the fast CSI feedback report includes one or more of:

means for reducing a bitwidth of a standard CSI feedback report for the fast CSI feedback report;

means for selecting a subset of CSI reporting types from a plurality of available CSI reporting types for including in the fast CSI feedback report;

means for selecting a subset of CSI processes from a plurality of available CSI processes for including in the fast CSI feedback report;

means for reducing CSI measurement processing of the reference signal measuring for the fast CSI feedback report; and

means for reducing a transmission duration of CSI reporting for the fast CSI feedback report.

15. The apparatus of claim 12, further including:

means for generating a non-fast CSI feedback report based, at least in part, on the reference signal; and

means for transmitting the non-fast CSI feedback report at a later interval from the fast CSI feedback report.

16. The apparatus of claim 15, wherein the non-fast CSI feedback report includes one of:

a standard CSI feedback report;

or

a refined CSI feedback report, wherein the refined CSI feedback report is based on one of;

additional channel information or interference information.

17. The apparatus of claim 12, wherein the fast CSI feedback report is transmitted in an uplink subframe following a downlink subframe from which the reference signal is detected.

18. The apparatus of claim 12, wherein the means for transmitting the fast CSI feedback report includes:

means for determining, by the UE, an earliest available uplink carrier of a plurality of uplink carriers; and

means for transmitting the fast CSI feedback report on the determined earliest available uplink carrier.

19. The apparatus of claim 12, wherein the shared spectrum is at least one of an unlicensed spectrum or a spectrum allowing sharing among a plurality of operators.

20. A non-transitory computer-readable medium having program code recorded thereon, the program code including:

program code for causing a computer to detect, by a user equipment (UE), a reference signal from a serving base station over a carrier of a shared spectrum;

program code for causing the computer to measure, by the UE, the reference signal;

program code for causing the computer to generate, by the UE, a fast channel station information (CSI) feedback report based on the measured reference signal; and

program code for causing the computer to transmit, by the UE, the fast CSI feedback report to the serving base station.

21. The computer program product of claim 20, wherein the program code for causing the computer to detect includes:

program code for causing the computer to detect the reference signal in a first subframe of a transmission frame of the serving base station.

22. The computer program product of claim 20, wherein the program code for causing the computer to generate the fast CSI feedback report includes one or more of:

program code for causing the computer to reduce a bitwidth of a standard CSI feedback report for the fast CSI feedback report;

program code for causing the computer to select a subset of CSI reporting types from a plurality of available CSI reporting types for including in the fast CSI feedback report;

program code for causing the computer to select a subset of CSI processes from a plurality of available CSI processes for including in the fast CSI feedback report;

program code for causing the computer to reduce CSI measurement processing of the reference signal measuring for the fast CSI feedback report; and

program code for causing the computer to reduce a transmission duration of CSI reporting for the fast CSI feedback report.

23. The computer program product of claim 20, wherein the fast CSI feedback report is transmitted in an uplink subframe following a downlink subframe from which the reference signal is detected.

24. The computer program product of claim 20, wherein the shared spectrum is at least one of an unlicensed spectrum or a spectrum allowing sharing among a plurality of operators.

25. An apparatus configured for wireless communication, the apparatus comprising:

at least one processor; and

a memory coupled to the at least one processor,

wherein the at least one processor is configured;

to detect, by a user equipment (UE), a reference signal from a serving base station over a carrier of a shared spectrum;

to measure, by the UE, the reference signal;

to generate, by the UE, a fast channel station information (CSI) feedback report based on the measured reference signal; and

to transmit, by the UE, the fast CSI feedback report to the serving base station.

26. The apparatus of claim 25, wherein the configuration of the at least one processor to detect includes configuration to detect the reference signal in a first subframe of a transmission frame of the serving base station.

27. The apparatus of claim 25, wherein the configuration of the at least one processor to generate the fast CSI feedback report includes configuration of the at least one processor to one or more of:

reduce a bitwidth of a standard CSI feedback report for the fast CSI feedback report;

select a subset of CSI reporting types from a plurality of available CSI reporting types for including in the fast CSI feedback report;

select a subset of CSI processes from a plurality of available CSI processes for including in the fast CSI feedback report;

reduce CSI measurement processing of the reference signal measuring for the fast CSI feedback report; and

reduce a transmission duration of CSI reporting for the fast CSI feedback report.

28. The apparatus of claim 25, wherein the fast CSI feedback report is transmitted in an uplink subframe following a downlink subframe from which the reference signal is detected.

29. The apparatus of claim 28, wherein, in response to receiving the fast CSI reporting indicator indicating to disable fast CSI reporting, the UE disables each one or more of the configuration of the at least one processor to measure, to generate, and to transmit occurring after the fast CSI reporting indicator is received.

30. The apparatus of claim 25, wherein the shared spectrum is at least one of an unlicensed spectrum or a spectrum allowing sharing among a plurality of operators.