Apparatus, method, and system relating to minimization of drive tests (MDT) measurements

1. An apparatus comprising:

a memory storing instructions; and

one or more processors configured to execute the instructions to:

acquire target cell information indicating a target cell of Minimization of Drive Tests (MDT) measurements in an idle mode of a terminal apparatus, and

transmit the target cell information to the terminal apparatus,

wherein the target cell includes a downlink only cell which is used for downlink communication in a user plane and is not used for communication in a control plane, and

wherein the downlink only cell is used as a secondary cell of carrier aggregation but is not used as a primary cell of carrier aggregation.

2. The apparatus according to claim 1 , wherein

the target cell information is included in a configuration parameter for MDT in the idle mode, and

the one or more processors are further configured to execute the instructions to transmit a message including the configuration parameter to the terminal apparatus.

3. The apparatus according to claim 2 , wherein the message is a Logged Measurement Configuration message.

4. The apparatus according to claim 1 , wherein the one or more processors are further configured to execute the instructions to:

acquire initiation condition information relating to an initiation condition of the MDT measurements, and

transmit the initiation condition information to the terminal apparatus.

5. The apparatus according to claim 4 , wherein

the initiation condition includes that a specific cell is selected in cell reselection, and

the initiation condition information includes cell information indicating the specific cell.

6. The apparatus according to claim 4 , wherein

the initiation condition includes that a measurement value of the downlink only cell is better than a threshold, and

the initiation condition information includes threshold information indicating the threshold.

7. The apparatus according to claim 1 , wherein the one or more processors are further configured to execute the instructions to:

acquire termination condition information relating to a termination condition of the MDT measurements, and

transmit the termination condition information to the terminal apparatus.

8. The apparatus according to claim 7 , wherein

the termination condition includes that a measurement value of the downlink only cell is worse than a threshold, and

the termination condition information includes threshold information indicating the threshold.

9. The apparatus according to claim 7 , wherein

the termination condition includes that a specific cell is selected in cell reselection, and

the termination condition information includes cell information indicating the specific cell.

10. The apparatus according to claim 7 , wherein

the termination condition includes that a measurement time period expires, and

the termination condition information includes time period information indicating the measurement time period.

11. The apparatus according to claim 5 , wherein

the apparatus is a base station, a base station apparatus for the base station, or a module for the base station apparatus, and

the downlink only cell is a cell of the base station.

12. The apparatus according to claim 6 , wherein

the apparatus is a base station, a base station apparatus for the base station, or a module for the base station apparatus, and

the downlink only cell is a cell of another base station different from the base station.

13. The apparatus according to claim 1 , wherein the MDT measurements are Logged MDT measurements.

14. The apparatus according to claim 1 , wherein the target cell information includes a cell ID of the downlink only cell, band information indicating a frequency band of the downlink only cell, or frequency information indicating a frequency of the downlink only cell.

15. The apparatus according to claim 1 , wherein the downlink only cell is a cell in a downlink-dedicated band.

16. The apparatus according to claim 1 , wherein the apparatus is a base station, a base station apparatus for a base station, or a module for the base station apparatus.

17. An apparatus comprising:

a memory storing instructions; and

one or more processors configured to execute the instructions to:

acquire target cell information indicating a target cell of Minimization of Drive Tests (MDT) measurements in an idle mode of a terminal apparatus, the target cell information being transmitted by a base station, and the target cell including a downlink only cell which is used for downlink communication in a user plane and is not used for communication in a control plane and which is used as a secondary cell of carrier aggregation but is not used as a primary cell of carrier aggregation; and

perform the MDT measurements on the downlink only cell that the target cell information indicates.

18. The apparatus according to claim 17 , wherein the one or more processors are further configured to execute the instructions to:

acquire initiation condition information relating to an initiation condition of the MDT measurements, the initiation condition information being transmitted by the base station, and

initiate the MDT measurements based on the initiation condition information.

19. The apparatus according to claim 17 , wherein the one or more processors are further configured to execute the instructions to:

acquire termination condition information relating to a termination condition of the MDT measurements, the termination condition information being transmitted by the base station, and

terminate the MDT measurements based on the termination condition information.

20. A method comprising:

acquiring target cell information indicating a target cell of Minimization of Drive Tests (MDT) measurements in an idle mode of a terminal apparatus; and

transmitting the target cell information to the terminal apparatus,

wherein the target cell includes a downlink only cell which is used for downlink communication in a user plane and is not used for communication in a control plane, and

wherein the downlink only cell is used as a secondary cell of carrier aggregation but is not used as a primary cell of carrier aggregation.