CSI-RS for AMM measurements

1. A method for use in a network node of transmitting a measurement signal for evaluating a quality of a link from a cell, the method comprising:

determining a first virtual identifier for a first link;

determining a group of one or more channel state information reference signal (CSI-RS) sequences that are available to be transmitted from the cell;

associating a frequency resource allocation, a time resource allocation, a CSI-RS sequence from the group of one or more CSI-RS sequences, and a layer allocation with the first virtual identifier; and

transmitting a first CSI-RS for measurement using the frequency resource allocation, time resource allocation, CSI-RS sequence, and layer allocation associated with the first virtual identifier, the first virtual identifier mapping to a cell identifier and uniquely identifying a beam in a measurement region including multiple cells and a portion of the first virtual identifier being encoded in a sequence of the transmitted first CSI-RS.

2. The method of claim 1 , wherein determining the first virtual identifier is based on a cell identifier of the cell.

3. The method of claim 1 , wherein determining the first virtual identifier is based on at least one of a beam identifier in a multi-beam cell, a transmission reception point (TRP) in a multi-TRP cell, or a sector in a multi-sector cell.

4. The method of claim 1 , further comprising transmitting CSI-RS configuration information to a wireless device, the CSI-RS configuration information comprising, for each CSI-RS of a plurality of CSI-RS, one or more of a frequency resource allocation, a time resource allocation, a CSI-RS sequence, and a layer allocation.

5. The method of claim 1 , further comprising:

determining a second virtual identifier for a second link;

associating one or more of a frequency resource allocation, a time resource allocation, a CSI-RS sequence from the group of one or more CSI-RS sequences, and a layer allocation with the second virtual identifier;

transmitting a second CSI-RS for measurement using one or more of the frequency resource allocation, time resource allocation, CSI-RS sequence, and layer allocation associated with the second virtual identifier;

receiving a measurement report, the measurement report comprising a virtual identifier; and

determining whether the measurement report is associated with the first link or the second link based on the virtual identifier in the measurement report.

6. A network node operable to transmit a measurement signal for evaluating a quality of a link from a cell, the network node comprising processing circuitry configured to:

determine a first virtual identifier for a first link;

determine a group of one or more channel state information reference signal (CSI-RS) sequences that are available to be transmitted from the cell;

associate a frequency resource allocation, a time resource allocation, a CSI-RS sequence from the group of one or more CSI-RS sequences, and a layer allocation with the first virtual identifier; and

transmit a first CSI-RS for measurement using the frequency resource allocation, time resource allocation, CSI-RS sequence, and layer allocation associated with the first virtual identifier, the first virtual identifier mapping to a cell identifier and uniquely identifying a beam in a measurement region including multiple cells and a portion of the first virtual identifier being encoded in a sequence of the transmitted first CSI-RS.

7. The network node of claim 6 , wherein the processing circuitry is operable to determine the first virtual identifier based on a cell identifier of the cell.

8. A method for use in a wireless device of measurement of a link quality, the method comprising:

obtaining channel state information reference signal (CSI-RS) configuration information, the CSI-RS configuration information comprising, for a plurality of CSI-RS, a frequency resource allocation, a time resource allocation, a CSI-RS sequence generator seed, a bandwidth allocation, and a layer allocation, the CSI-RS configuration information further comprising a virtual identifier for a link, the first virtual identifier mapping to a cell identifier and uniquely identifying a beam in a measurement region including multiple cells;

measuring a CSI-RS associated with the link according to the obtained CSI-RS configuration information; and

reporting a quality of the measured CSI-RS to a network node.

9. The method of claim 8 , wherein measuring the CSI-RS associated with the link comprises blindly searching the allocations in the CSI-RS configuration for the CSI-RS.

10. The method of claim 8 , further comprising determining a virtual identifier of the measured CSI-RS based on one or more of a frequency resource allocation, a time resource allocation, a CSI-RS sequence, a bandwidth allocation, and a layer allocation of the measured CSI-RS; and

wherein reporting the quality of the measured CSI-RS includes reporting the determined virtual identifier associated with the measured CSI-RS.

11. The method of claim 8 , further comprising detecting a system synchronization (SS) signal.

12. The method of claim 11 , wherein at least part of the CSI-RS configuration information is specified relative to a time and frequency position of the detected SS signal.

13. A wireless device capable of measurement of a link quality, the wireless device comprising processing circuitry configured to:

obtain channel state information reference signal (CSI-RS) configuration information, the CSI-RS configuration information comprising, for a plurality of CSI-RS, a frequency resource allocation, a time resource allocation, a CSI-RS sequence generator seed, a bandwidth allocation, and a layer allocation, the CSI-RS configuration information further comprising a virtual identifier for a link, the first virtual identifier mapping to a cell identifier and uniquely identifying a beam in a measurement region including multiple cells;

measure a CSI-RS associated with the link according to the obtained channel state information; and

report a quality of the measured CSI-RS to a network node.

14. The wireless device of claim 13 , wherein the processing circuitry is configured to measure the CSI-RS associated with the link by blindly searching the allocations in the CSI-RS configuration for the CSI-RS.