Controllable CSI-RS density

1. A method of configuring, in a network node of a wireless communication network, a reference signal resource in the wireless communication network, the method comprising:

obtaining a combination of a plurality of components to be used for a reference signal resource, the plurality of components being contained in one or more physical resource blocks of a slot; and

indicating, to one or more wireless devices, the combination of the plurality of components in the one or more physical resource blocks that are to be used for the reference signal resource,

wherein the physical resource block spans a plurality of subcarriers, and wherein indicating the combination of the plurality of components includes indicating one or more subcarrier indexes,

wherein the indication of the one or more subcarrier indexes includes a bitmap, and

wherein each bit in the bitmap uniquely corresponds to a subcarrier index and a set bit in the bitmap indicates that a component located at a subcarrier index corresponding to the set bit is part of the combination of the plurality of components used for the reference signal resource.

2. The method of claim 1 , wherein obtaining the combination of the plurality of components to be used for a reference signal resource comprises aggregating the plurality of components across two or more physical resource blocks, to form the reference signal resource.

3. The method of claim 1 , wherein obtaining the combination of the plurality of components to be used for a reference signal resource comprises aggregating one resource element (RE) per port, per physical resource block of the one or more physical resource blocks of the slot to form the reference signal resource.

4. The method of claim 1 , wherein a number of bits in the bitmap depends on a number of subcarriers in a component.

5. The method of claim 1 , wherein the number of bits in the bitmap is half the number of subcarriers in the physical resource block.

6. The method of claim 1 , wherein the reference signal resource is a CSI-RS resource.

7. The method of claim 1 , wherein each of the components corresponds to two or more subcarriers, the two or more subcarriers of each component being adjacent in frequency.

8. The method of claim 7 , wherein each component corresponds to two or more adjacent symbols.

9. The method of claim 1 , wherein the reference signal resource is used to perform at least one of:

link adaptation for the one or more wireless devices, and

beam management for the one or more wireless devices.

10. A method of obtaining, in a wireless device of a wireless communication network, an indication of a reference signal resource in the wireless communication network, the method comprising:

receiving an indication, from a network node, of a combination of a plurality of components contained in one or more physical resource blocks of a slot; and

using the indicated combination of the plurality of components for a reference signal resource,

wherein the physical resource block spans a plurality of subcarriers, and wherein indicating the combination of the plurality of components includes indicating one or more subcarrier indexes,

wherein the indication of the one or more subcarrier indexes includes a bitmap, and

wherein each bit in the bitmap uniquely corresponds to a subcarrier index and a set bit in the bitmap indicates that a component located at a subcarrier index corresponding to the set bit is part of the combination of a plurality of components used for the reference signal resource.

11. The method of claim 10 , wherein the indicated combination consists of one resource element (RE) per port, per physical resource block of the one or more physical resource blocks of the slot.

12. The method of claim 10 , wherein a number of bits in each of the one or more bitmaps depends on a number of subcarriers in a component.

13. The method of claim 10 , wherein the number of bits in the bitmap is half a number of subcarriers in the physical resource block.

14. The method of claim 10 , wherein each of the components corresponds to two or more subcarriers, the two or more of subcarriers of each component being adjacent in frequency.

15. The method of claim 14 , wherein each component corresponds to two or more adjacent symbols.

16. The method of claim 10 , wherein the reference signal resource is a CSI-RS resource.

17. The method of claim 16 , wherein the reference signal resource is used to perform at least one of:

link adaptation for the wireless device, and

beam management for the wireless device.

18. A user equipment (UE) for facilitating communications in a wireless communication network by obtaining an indication of a reference signal resource in the wireless communication network, the UE comprising:

an antenna configured to send and receive wireless signals;

a transceiver connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry;

the processing circuitry being configured to:

receive an indication, from a network node, of a combination of a plurality of components contained in one or more physical resource blocks of a slot; and

use the indicated combination of the plurality of components for a reference signal resource,

wherein the physical resource block spans a plurality of subcarriers, and wherein indicating the combination of the plurality of components includes indicating one or more subcarrier indexes,

wherein the indication of the one or more subcarrier indexes includes a bitmap, and

wherein each bit in the bitmap uniquely corresponds to a subcarrier index and a set bit in the bitmap indicates that a component located at a subcarrier index corresponding to the set bit is part of the combination of a plurality of components used for the reference signal resource.