Carrier measurements

1. An apparatus, comprising:

at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to:

acquire from a network a configuration for at least one secondary cell;

enter a radio resource control, RRC, inactive mode;

maintain at least part of the configuration during the inactive mode;

determine, based on the configuration, which carriers are to be measured during the RRC inactive mode;

perform measurements of the determined carriers during the RRC inactive mode;

provide the results of the measurements to the network upon entering an RRC connected mode,

wherein only a subset of the carriers indicated in the configuration are to be measured, and

wherein the subset includes those carriers that were activated within a predetermined duration before the entering the RRC inactive mode.

2. The apparatus of claim 1 , wherein the configuration comprises information indicating for at least some of the secondary cells of the configuration whether or not the corresponding carrier is to be measured during the RRC inactive mode, and wherein the determining is based on the information.

3. The apparatus of claim 2 , wherein the information comprises at least one of the following: an explicit indication for each carrier that is to be measured during the RRC inactive mode and an explicit indication for each carrier that is not to be measured during the RRC inactive mode.

4. The apparatus of claim 1 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to:

receive a state transition message from the network, the message comprising information indicating the configuration.

5. The apparatus of claim 1 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to:

acquire information of a validity duration indicating how long the determination of which carriers are to be measured during the RRC inactive mode is valid.

6. The apparatus of claim 5 , wherein the validity duration is indicated separately for each carrier that is to be measured, wherein at least two carriers to be measured have different validity durations.

7. The apparatus of claim 1 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to:

acquire information of a validity area indicating a geographical area within which the determination of which carriers to be measured during the RRC inactive mode is valid.

8. The apparatus of claim 1 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to:

enter the RRC connected mode and provide the results of the measurements to the network;

receive, from the network, an indication of triggering multicarrier connectivity, wherein at least one secondary cell to be utilized in the multicarrier connectivity are determined based on the provided results of the measurements;

apply multicarrier connectivity for communication with the network after entering the RRC connected mode, wherein connecting to the at least one secondary cell is based on the indication and the configuration acquired before entering the RRC inactive mode.

9. The apparatus of claim 1 , wherein the RRC connected mode is with a New Radio, NR, communication network and the apparatus is a user equipment operable at least in the NR communication network.

10. A method, the method comprising:

acquiring from a network a configuration for at least one secondary cell;

entering a radio resource control, RRC, inactive mode;

maintaining at least part of the configuration during the inactive mode;

determining, based on the configuration, which carriers are to be measured during the RRC inactive mode;

performing measurements of the determined carriers during the RRC inactive mode;

providing the results of the measurements to the network upon entering an RRC connected mode,

wherein only a subset of the carriers indicated in the configuration are to be measured, and

wherein the subset includes those carriers that were activated within a predetermined duration before the entering the RRC inactive mode.

11. The method of claim 10 , further comprising:

receiving a state transition message from the network, the message comprising information indicating the configuration.

12. The method of claim 10 , further comprising:

entering the RRC connected mode and providing the results of the measurements to the network;

receiving, from the network, an indication of triggering multicarrier connectivity, wherein at least one secondary cell to be utilized in the multicarrier connectivity are determined based on the provided results of the measurements;

applying multicarrier connectivity for communication with the network after entering the RRC connected mode, wherein connecting to the at least one secondary cell is based on the indication and the configuration acquired before entering the RRC inactive mode.

13. An apparatus, comprising:

at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to:

acquire from a network a configuration for at least one secondary cell;

enter a radio resource control, RRC, inactive mode;

maintain at least part of the configuration during the inactive mode;

determine, based on the configuration, which carriers are to be measured during the RRC inactive mode;

perform measurements of the determined carriers during the RRC inactive mode;

provide the results of the measurements to the network upon entering an RRC connected mode,

wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to:

acquire information of a validity duration indicating how long the determination of which carriers are to be measured during the RRC inactive mode is valid,

wherein the validity duration is indicated separately for each carrier that is to be measured, wherein at least two carriers to be measured have different validity durations.