Method and apparatus for reporting doppler information of time-varying channel in wireless communication systems

1 . A method performed by a user equipment (UE) in a communication system, the method comprising:

transmitting, to a base station, capability information indicating a capability for a time correlated channel state information (CSI) report;

receiving, from the base station, a first configuration enabling a time correlated CSI report and a second configuration indicating a mapping relationship between codepoints of an indicator and Doppler frequency shift values;

receiving, from the base station, one or more first CSI-reference signals (CSI-RSs) and one or more second CSI-RSs;

obtaining:

based on the one or more first CSI-RSs, a first Doppler frequency shift value according to the first configuration, wherein the first Doppler frequency shift value is non-zero; and

based on the one or more second CSI-RSs, a second Doppler frequency shift value according to the first configuration, wherein the second Doppler frequency shift value is zero,

transmitting, to the base station, a first time correlated CSI report including the indicator corresponding to a codepoint indicating the first Doppler frequency shift value and a second time correlated CSI report without the indicator,

wherein the codepoint of the indicator indicating the first Doppler frequency shift value is based on the second configuration,

wherein the first time correlated CSI report includes a bit indicating a presence of the indicator, and

wherein the second time correlated CSI report includes the bit indicating an absence of the indicator.

2 . The method of claim 1 ,

wherein the second configuration indicates a table among a plurality of candidate tables,

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the table, and

wherein each of the plurality of candidate tables defines a different mapping relationship between the codepoints of the indicator and the Doppler frequency shift values.

3 . The method of claim 1 ,

wherein the second configuration indicates a maximum value among a plurality of candidate maximum values for a Doppler frequency shift value, and

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the maximum value.

4 . A method performed by a base station in a communication system, the method comprising:

receiving, from a user equipment (UE), capability information indicating a capability for a time correlated channel state information (CSI) report;

transmitting, to the UE, a first configuration enabling a time correlated CSI report and a second configuration indicating a mapping relationship between codepoints of an indicator and Doppler frequency shift values;

transmitting, to the UE, one or more first CSI-reference signals (CSI-RSs) and one or more second CSI-RSs, wherein the one or more first CSI-RSs are associated with a first Doppler frequency shift value and the one or more second CSI-RSs are associated with a second Doppler frequency shift value; and

receiving, from the UE, a first time correlated CSI report including an indicator corresponding to a codepoint indicating the first Doppler frequency shift value, and a second time correlated CSI report without the indicator,

wherein the first Doppler frequency shift value is non-zero,

wherein the second Doppler frequency shift value is zero,

wherein the codepoint of the indicator indicating the first Doppler frequency shift value is based on the second configuration,

wherein the first time correlated CSI report includes a bit indicating a presence of the indicator, and

wherein the second time correlated CSI report includes the bit indicating an absence of the indicator.

5 . The method of claim 4 ,

wherein the second configuration indicates a table among a plurality of candidate tables,

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the table, and

wherein each of the plurality of candidate tables defines a different mapping relationship between the codepoints of the indicator and the Doppler frequency shift values.

6 . The method of claim 4 ,

wherein the second configuration indicates a maximum value among a plurality of candidate maximum values for a Doppler frequency shift value, and

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the maximum value.

7 . A user equipment (UE) in a communication system, the UE comprising:

a transceiver; and

at least one processor configured to:

transmit, to a base station, capability information indicating a capability for a time correlated channel state information (CSI) report,

receive, from the base station, a first configuration enabling a time correlated CSI report and a second configuration indicating a mapping relationship between codepoints of an indicator and Doppler frequency shift values,

receive, from the base station, one or more first CSI-reference signals (CSI-RSs) and one or more second CSI-RSs,

obtain:

based on the one or more first CSI-RSs, a first Doppler frequency shift value according to the first configuration, wherein the first Doppler frequency shift value is non-zero, and

based on the one or more second CSI-RSs, a second Doppler frequency shift value according to the first configuration, wherein the second Doppler frequency shift value is zero,

transmit, to the base station, a first time correlated CSI report including the indicator corresponding to a codepoint indicating the first Doppler frequency shift value and a second time correlated CSI report without the indicator,

wherein the codepoint of the indicator indicating the first Doppler frequency shift value is based on the second configuration,

wherein the first time correlated CSI report includes a bit indicating a presence of the indicator, and

wherein the second time correlated CSI report includes the bit indicating an absence of the indicator.

8 . The UE of claim 7 ,

wherein the second configuration indicates a table among a plurality of candidate tables,

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the table, and

wherein each of the plurality of candidate tables defines a different mapping relationship between the codepoints of the indicator and the Doppler frequency shift values.

9 . The UE of claim 7 ,

wherein the second configuration indicates a maximum value among a plurality of candidate maximum values for a Doppler frequency shift value, and

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the maximum value.

10 . A base station in a communication system, the base station comprising:

a transceiver; and

at least one processor configured to:

receive, from a user equipment (UE), capability information indicating a capability for a time correlated channel state information (CSI) report,

transmit, to the UE, a first configuration enabling a time correlated CSI report and a second configuration indicating a mapping relationship between codepoints of an indicator and Doppler frequency shift values,

transmit, to the UE, one or more first CSI-reference signals (CSI-RSs) and one or more second CSI-RSs, wherein the one or more first CSI-RSs are associated with a first Doppler frequency shift value and the one or more second CSI-RSs are associated with a second Doppler frequency shift value, and

receive, from the UE, a first time correlated CSI report including an indicator corresponding to a codepoint indicating the first Doppler frequency shift value, and a second time correlated CSI report without the indicator,

wherein the first Doppler frequency shift value is non-zero,

wherein the second Doppler frequency shift value is zero,

wherein the codepoint of the indicator indicating the first Doppler frequency shift value is based on the second configuration,

wherein the first time correlated CSI report includes a bit indicating a presence of the indicator, and

wherein the second time correlated CSI report includes the bit indicating an absence of the indicator.

11 . The base station of claim 10 ,

wherein the second configuration indicates a table among a plurality of candidate tables,

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the table, and

wherein each of the plurality of candidate tables defines a different mapping relationship between the codepoints of the indicator and the Doppler frequency shift values.

12 . The base station of claim 10 ,

wherein the second configuration indicates a maximum value among a plurality of candidate maximum values for a Doppler frequency shift value, and

wherein the mapping relationship between codepoints of the indicator and Doppler frequency shift values is determined based on the maximum value.