Method and apparatus for performing measurement in wireless communication system
A method for and apparatus for performing a measurement in a wireless communication system is provided. A wireless device determines information about a measurement type, the measurement type indicating one of a first measurement object and a second measurement object and performs measurement using a measurement signal at subframe(s) configured in the measurement object indicated by the measurement type. The measurement signal includes one of a discovery signal, a measurement reference signal (MRS) and a cell-common RS (CRS).
1. A method for performing a measurement at a user equipment (UE) in a mobile communication system, the method comprising:
receiving, at the UE from a primary cell, measurement configuration information of a discovery signal of a secondary cell in an off-state; and
based on the measurement configuration information, measuring, at the UE, a Reference Signal Received Power (RSRP) or a Received Signal Strength Indicator (RSSI) of the discovery signal,
wherein the measurement configuration information indicates a frequency of the discovery signal, a periodicity of the discovery signal, and a subframe offset of the discovery signal,
wherein the measurement configuration information further indicates that the UE should not assume to receive a cell reference signal (CRS) within a subframe except for a subframe configured to receive the discovery signal, and
wherein the measurement configuration information is received via a radio resource control (RRC) message.
2. The method of claim 1 , wherein the off-state is a state where no UE is currently attached to the secondary cell.
3. The method of claim 1 , wherein the discovery signal is transmitted only from the secondary cell in the off-state.
4. The method of claim 1 , wherein the received CRS from the secondary cell is not used for a data demodulation.
5. The method of claim 1 , further comprising:
based on the measuring, transmitting information indicating that a base station should cause the secondary cell to change from the off-state to an on-state for handover.
6. The method of claim 5 , wherein the on-state corresponds to a state where the secondary cell transmits synchronization signals.
7. The method of claim 1 , wherein the off-state corresponds to a state where the secondary cell transmits the discovery signal in one or more subframes allocated for an on-state synchronization signal.
8. The method of claim 1 , wherein the off-state corresponds to a state where the secondary cell transmits the discovery signal in one or more subframes allocated for an on-state cell-reference signal.
9. The method of claim 1 , wherein a pattern of the discovery signal associated with the off-state corresponds to a reference signal pattern associated with an on-state.
10. The method of claim 1 ,
wherein the frequency of the discovery signal indicates a specific frequency for which the measurement configuration information is valid,
wherein the periodicity of the discovery signal indicates a periodicity of the discovery signal measurement timing configuration, and
wherein the subframe offset of the discovery signal indicates a specific offset of the measurement timing configuration of the discovery signal in a number of subframe(s).
11. A user equipment (UE) performing a measurement in a mobile communication system, the UE comprising:
a transceiver configured to receive a radio signal; and
a processor configured to:
receive, from a primary cell, measurement configuration information of a discovery signal of a secondary cell in an off-state; and
based on the measurement configuration information, measure a Reference Signal Received Power (RSRP) or a Received Signal Strength Indicator (RSSI) of the discovery signal,
wherein the measurement configuration information indicates a frequency of the discovery signal, a periodicity of the discovery signal, and a subframe offset of the discovery signal,
wherein the measurement configuration information further indicates that the UE should not assume to receive a cell reference signal (CRS) within a subframe except for a subframe configured to receive the discovery signal, and
wherein the measurement configuration information is received via a radio resource control (RRC) message.
12. The UE of claim 11 , wherein the off-state is a state where no UE is currently attached to the secondary cell.
13. The UE of claim 11 , wherein the discovery signal is transmitted only from the secondary cell in the off-state.
14. The UE of claim 11 , wherein the received CRS from the secondary cell is not used for a data demodulation.
15. The UE of claim 11 , wherein, based on the measuring, the processor is further configured to transmit information indicating that a base station should cause the secondary cell to change from the off-state to the to an on-state for handover.
16. The UE of claim 15 , wherein the on-state corresponds to a state where the secondary cell transmits synchronization signals.
17. The UE of claim 11 , wherein the off-state corresponds to a state where the secondary cell transmits the discovery signal in one or more subframes allocated for an on-state synchronization signal.
18. The UE of claim 11 , wherein the off-state corresponds to a state where the secondary cell transmits the discovery signal in one or more subframes allocated for an on-state cell-reference signal.
19. UE of claim 11 , wherein a pattern of the discovery signal associated with the off-state corresponds to a reference signal pattern associated with an on-state.
20. The UE of claim 11 ,
wherein the frequency of the discovery signal indicates a specific frequency for which the measurement configuration information is valid,
wherein the periodicity of the discovery signal indicates a periodicity of the discovery signal measurement timing configuration, and
wherein the subframe offset of the discovery signal indicates a specific offset of the measurement timing configuration of the discovery signal in a number of subframe(s).