METHODS AND APPARATUS FOR CSI MEASUREMENT CONFIGURATION AND REPORTING ON UNLICENSED SPECTRUM

• US 20160227428A1
• Filed: 01/25/2016
• Published: 08/04/2016
• Est. Priority Date: 01/30/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Novlan, Thomas, Ng, Boon Loong, Zhang, Jianzhong, Onggosanusi, Eko, Papasakellariou, Aris
• Granted Patent: US 10,129,782 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]

Abstract

A method for channel state information (CSI) measurement. The method comprises receiving a reference signal that is periodically transmitted in one or more discovery reference signal (DRS) occasions from an eNodeB (eNB) operating in a cell over an unlicensed spectrum band, wherein the reference signal in the one or more DRS occasions is dropped in accordance with at least one of a listen before talk (LBT) operation and a discontinuous transmission (DTX) operation and the reference signal includes at least one of a cell-specific reference signal (CRS) and a channel state information-reference signal (CSI-RS). The method further comprises measuring the received reference signal to generate a CSI measurement report and transmitting the CSI measurement report to the eNB according to a configuration received from the eNB.

Claims

1. A user equipment (UE) comprising:

a transceiver configured to;

receive a reference signal that is periodically transmitted in one or more discovery reference signal (DRS) occasions from an eNodeB (eNB) operating in a cell over an unlicensed spectrum band, wherein the reference signal in the one or more DRS occasions is dropped in accordance with at least one of a listen before talk (LBT) operation and a discontinuous transmission (DTX) operation, the reference signal including at least one of a cell-specific reference signal (CRS) and a channel state information-reference signal (CSI-RS); and

transmit a CSI measurement report to the eNB according to a configuration received from the eNB; and

at least one processor configured to measure the received reference signal to generate the CSI measurement report.

2. The UE of claim 1, wherein the at least one processor is further configured to identify that one or more reference signals are received aperiodically in the one or more DRS occasions.

3. The UE of claim 2, wherein a presence of the one or more reference signals in the one or more DRS occasions is configured by an L1 signal received from the eNB.

4. The UE of claim 1, wherein the configuration is determined from a higher layer signal or an L1 signal received from the eNB, the configuration determined independently from a configuration for radio resource measurement (RRM) reports.

5. The UE of claim 1, wherein the CSI measurement report includes bitmap information indicating whether a CSI measurement based on the received reference signal is included in the CSI measurement report.

6. The UE of claim 1, wherein the reference signal is received and measured in a first subframe of multiple detected subframes including one or more synchronization and common reference signals in a period of a DRS measurement timing configuration.

7. A method for channel state information (CSI) measurement in a wireless communication system, the method comprises:

receiving, by a user equipment (UE), a reference signal that is periodically transmitted in one or more discovery reference signal (DRS) occasions from an eNodeB (eNB) operating in a cell over an unlicensed spectrum band, wherein the reference signal in the one or more DRS occasions is dropped in accordance with at least one of a listen before talk (LBT) operation and a discontinuous transmission (DTX) operation, the reference signal including at least one of a cell-specific reference signal (CRS) and a channel state information-reference signal (CSI-RS);

measuring, by the UE, the received reference signal to generate a CSI measurement report; and

transmitting the CSI measurement report to the eNB according to a configuration received from the eNB.

8. The method of claim 7, further comprising:

identifying that one or more reference signals are received aperiodically in the one or more DRS occasions.

9. The method of claim 8, wherein a presence of the one or more reference signals in the one or more DRS occasions is configured by an L1 signal received from the eNB.

10. The method of claim 7, wherein the configuration is determined from a higher layer signal or an L1 signal received from the eNB, the configuration determined independently from a configuration for radio resource measurement (RRM) reports.

11. The method of claim 7, wherein the CSI measurement report includes bitmap information indicating whether a CSI measurement based on the received reference signal is included in the CSI measurement report.

12. The method of claim 7, wherein the reference signal is received and measured in a first subframe of multiple detected subframes including one or more synchronization and common reference signals in a period of a DRS measurement timing configuration.

13. An eNodeB (eNB) comprising:

a transceiver configure to;

periodically transmit a reference signal in one or more discovery reference signal (DRS) occasions to a user equipment (UE) operating in a cell over an unlicensed spectrum band, wherein the reference signal in the one or more DRS occasions is dropped in accordance with at least one of a listen before talk (LBT) operation and a discontinuous transmission (DTX) operation, the reference signal including at least one of a cell-specific reference signal (CRS) and a channel state information-reference signal (CSI-RS); and

receive a CSI measurement report from the UE according to a configuration transmitted to the UE; and

at least one processor configured to process the CSI measurement report received from the UE.

14. The eNB of claim 13, wherein the at least one processor is further configured to identify that one or more reference signals are transmitted aperiodically in the one or more DRS occasions.

15. The eNB of claim 14, wherein a presence of the one or more reference signals in the one or more DRS occasions is configured by an L1 signal transmitted to the UE.

16. The eNB of claim 13, wherein the at least one processor is further configured to:

identify whether the CSI measurement is included in the CSI measurement report based on bitmap information received from the UE, the bitmap information being included in the CSI measurement report; and

process the CSI measurement report.

17. The eNB of claim 13, wherein the configuration is determined from a higher layer signal or an L1 signal transmitted from the eNB, the configuration determined independently from a configuration for radio resource measurement (RRM) reports.

18. The eNB of claim 13, wherein the eNB uses a latest available CSI measurement report when the eNB receives the CSI measurement report including the bitmap information indicating that the CSI measurement has not been successfully achieved at the UE.

19. The eNB of claim 13, wherein the at least one processor is further configured to drop one or more reference signals when resources for the one or more reference signals are overlapped with resources for one or more signals to be transmitted in the DRS occasions.

20. The eNB of claim 13 wherein the transceiver is further configured to transmit the reference signals using one or more subframes including one or more synchronization and common reference signals in a period of a DRS measurement timing configuration.