Measurement in NTN communication

1 . A method, comprising:

receiving, by a user equipment (UE) from a network, a synchronization signal;

receiving, by the UE from the network, system information related to NTN, based on the UE connecting to the network via a non-terrestrial networks (NTN) satellite;

transmitting, by the UE to the network, a random access preamble;

based on that the random access preamble is transmitted, receiving, by the UE from the network, a random access response;

receiving, by the UE from the network, measurement information; and

receiving, by the UE from the network, orbital information of a target satellite,

wherein the measurement information includes information related to measurement time point for a measurement of the UE;

based on the received orbital information of the target satellite, determining, by the UE, a measurable time point at which an altitude angle of the target satellite calculated from the received orbital information of the target satellite is greater than a threshold;

based on that the measurement time point is earlier than the measurable time point, transmitting, by the UE to the network, a failure message; and

performing, by the UE, measurement at the measurable time point.

2 . The method of claim 1 ,

wherein the measurement information includes information related to synchronization signal block (SSB) measurement timing configuration (SMTC) or measurement gap (MG).

3 . The method of claim 1 , further comprising:

wherein the measurement information further includes information related to measurement period for the UE's measurement,

adjusting, by the UE, the measurement period, based on the UE failing the measurement at the measurable time point.

4 . The method of claim 3 , further comprising:

reporting, by the UE to the network, adjustment of the measurement period.

5 . The method of claim 1 ,

wherein the threshold is 10 degrees.

6 . A user equipment (UE), comprising:

at least one transceiver;

at least one processor; and

at least one memory connected to the at least one processor and storing instructions that, based on being executed by the at least one processor, cause the UE to perform operations comprising:

receiving, from a network, a synchronization signal;

receiving, from the network, system information related to NTN, based on the UE connecting to the network via a non-terrestrial networks (NTN) satellite;

transmitting, to the network, a random access preamble;

based on that the random access preamble is transmitted, receiving, from the network, a random access response;

receiving, from the network, measurement information; and

receiving, from the network, orbital information of a target satellite,

wherein the measurement information includes information related to measurement time point for a measurement of the UE;

based on the received orbital information of the target satellite, determining a measurable time point at which an altitude angle of the target satellite calculated from the received orbital information of the target satellite is greater than a threshold;

based on that the measurement time point is earlier than the measurable time point, transmitting, by the UE to the network, a failure message; and

performing measurement at the measurable time point.

7 . The UE of claim 6 ,

wherein the measurement information includes information related to synchronization signal block (SSB) measurement timing configuration (SMTC) or measurement gap (MG).

8 . The UE of claim 6 , further comprising:

wherein the measurement information further includes information related to measurement period for the UE's measurement,

wherein the operations further comprise: adjusting the measurement period, based on the UE failing the measurement at the measurable time point.

9 . The UE of claim 8 ,

wherein the operations further comprise: reporting, to the network, adjustment of the measurement period.

10 . The UE of claim 6 ,

wherein the threshold is 10 degrees.

11 . A processing device, comprising:

at least one processor; and

at least one memory connected to the at least one processor and storing instructions that, based on being executed by the at least one processor, cause the processing device to perform operations comprising:

receiving, from a network, a synchronization signal;

receiving, from the network, system information related to NTN, based on the processing device connecting to the network via a non-terrestrial networks (NTN) satellite;

transmitting, to the network, a random access preamble;

based on that the random access preamble is transmitted, receiving, from the network, a random access response;

receiving, from the network, measurement information; and

receiving, from the network, orbital information of a target satellite,

wherein the measurement information includes information related to measurement time point a measurement of the processing device;

based on the received orbital information of the target satellite, determining a measurable time point at which an altitude angle of the target satellite calculated from the received orbital information of the target satellite is greater than a threshold;

based on that the measurement time point is earlier than the measurable time point, transmitting, by the processing device to the network, a failure message; and

performing measurement at the measurable time point.