Method for transmitting or receiving signal in wireless communication system, and device therefor
The present invention relates to a method for receiving a signal in a wireless communication system supporting narrowband Internet of things (NB-IoT) operated in time division duplex (TDD) and a device therefor, the method comprising the steps of: configuring a search space for a physical downlink control channel; and monitoring the physical downlink control channel on the basis of the configured search space, wherein the search space is configured by a TDD special subframe from which aggregation level 1 has been excluded, and the TDD special subframe indicates a subframe including a downlink period, a guard period, and an uplink period.
1. A method for receiving a signal by a user equipment (UE) in a 3rd generation partnership project (3GPP)-based wireless communication system supporting narrowband Internet of Things (NB-IoT) operating in time division duplex (TDD), the method comprising:
configuring a search space for a narrowband physical downlink control channel (NPDCCH); and
monitoring NPDCCH candidates in a corresponding subframe based on the configured search space,
wherein each NPDCCH candidate is configured with one or more narrowband control channel elements (NCCEs) based on a corresponding aggregation level (AL), and
wherein, in monitoring the NPDCCH candidates:
based on that the corresponding subframe is a TDD special subframe between a downlink subframe and an uplink subframe, where the TDD special subframe includes a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS), the UE monitors each NPDCCH candidate in the TDD special subframe, other than an AL-1-based NPDCCH candidate with one NCCE, and
wherein the AL-1 based NPDCCH candidate is not monitored by the UE only in the TDD special subframe.
2. The method of claim 1 , wherein the UE monitors an AL-2-based NPDCCH candidate with two NCCEs in the TDD special subframe.
3. The method of claim 1 , wherein based on a number of NPDCCH repetitions being equal to 1, the AL-1-based NPDCCH candidate is not monitored by the UE in the TDD special subframe.
4. The method of claim 1 , wherein based on a downlink period of the TDD special subframe including a specific number of orthogonal frequency division multiplexing (OFDM) symbols or less, the AL-1-based NPDCCH candidate is not monitored by the UE in the TDD special subframe.
5. The method of claim 1 , wherein based on a value indicated by control format indicator (CFI) information for the TDD special subframe being less than a specific value, the AL-1-based NPDCCH candidate is not monitored by the UE in the TDD special subframe.
6. The method of claim 1 , wherein based on a maximum number of NPDCCH repetitions being configured to be less than a specific value, the AL-1-based NPDCCH candidate is not monitored by the UE in the TDD special subframe.
7. The method of claim 1 , wherein based on a number of NPDCCH repetitions being less than a specific value, the AL-1-based NPDCCH candidate is not monitored by the UE in the TDD special subframe.
8. The method of claim 7 , wherein the specific value is indicated by higher layer signaling, or determined based on a maximum number of NPDCCH repetitions.
9. The method of claim 8 , wherein one NCCE occupies 6 subcarriers.
10. The method of claim 1 , wherein the NPDCCH is mapped on at least one of the DwPTS of the TDD special subframe or the downlink subframe.
11. A non-transitory processor readable medium recorded thereon instructions for executing the method of claim 1 .
12. The method of claim 1 , wherein the UE does not monitor the AL-1 based NPDCCH candidate in the TDD special subframe, irrespective of a number of NCCEs included in the TDD special subframe.
13. The method of claim 1 , wherein the AL-1 based NPDCCH candidate is not monitored in all TDD special subframe configured in the UE.
14. The method of claim 1 , wherein the AL-1 based NPDCCH candidate is not monitored by the UE, only based on the corresponding subframe being the TDD special subframe.
15. A user equipment (UE) configured to receive a signal in a 3rd generation partnership project (3GPP)-based wireless communication system supporting narrowband Internet of Things (NB-IoT) operating in time division duplex (TDD), the UE comprising:
a radio frequency (RF) transceiver; and
a processor operatively connected to the RF transceiver,
wherein the processor is configured to configure a search space for a narrowband physical downlink control channel (NPDCCH) and monitor NPDCCH candidates in a corresponding subframe based on the configured search space,
wherein each NPDCCH candidate is configured with one or more narrowband control channel elements (NCCEs) based on a corresponding aggregation level (AL), and
wherein, in monitoring the NPDCCH candidates:
based on that the corresponding subframe is a TDD special subframe between a downlink subframe and an uplink subframe, where the TDD special subframe includes a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS), the processor monitors each NPDCCH candidate in the TDD special subframe, other than an AL-1-based NPDCCH candidate with one NCCE, and
wherein the AL-1 based NPDCCH candidate is not monitored by the UE only in the TDD special subframe.
16. A processing device configured to control a user equipment (UE) to receive a signal in a 3rd generation partnership project (3GPP)-based wireless communication system supporting narrowband Internet of Things (NB-IoT) operating in time division duplex (TDD), the processing device comprising:
a memory including executable codes; and
a processor operatively connected to the memory,
wherein the processor is configured to execute the executable codes to implement operations comprising:
configuring a search space for a narrowband physical downlink control channel (NPDCCH); and
monitoring NPDCCH candidates in a corresponding subframe based on the configured search space,
wherein each NPDCCH candidate is configured with one or more narrowband control channel elements (NCCEs) based on a corresponding aggregation level (AL), and
wherein, monitoring the NPDCCH candidates comprises:
based on that the corresponding subframe is a TDD special subframe between a downlink subframe and an uplink subframe, where the TDD special subframe includes a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS), monitoring each NPDCCH candidate in the TDD special subframe, other than an AL-1-based NPDCCH candidate with one NCCE, and
wherein the AL-1 based NPDCCH candidate is not monitored by the UE only in the TDD special subframe.
17. A method for transmitting a signal by a base station (BS) in a 3rd generation partnership project (3GPP)-based wireless communication system supporting narrowband Internet of Things (NB-IoT) operating in time division duplex (TDD), the method comprising:
configuring a search space for narrowband physical downlink control channel (NPDCCH) candidates each configured with one or more narrowband control channel elements (NCCEs) based on a corresponding aggregation level (AL); and
transmitting an NPDCCH signal, in a corresponding subframe, based on the configured search space,
wherein, in transmitting the NPDCCH signal,
based on that the corresponding subframe is a TDD special subframe between a downlink subframe and an uplink subframe, which includes a downlink pilot time slot (DwPTS), a guard period (GP) and an uplink pilot time slot (UpPTS), the BS transmits the NPDCCH signal through a specific NPDCCH candidate in the TDD special subframe other than an AL-1 based NPDCCH candidate with 1-NCCE, and
wherein the AL-1 based NPDCCH candidate is not used for the NPDCCH signal only in the TDD special subframe.
18. A base station (BS) configured to support a 3rd generation partnership project (3GPP)-based wireless communication, the BS comprising:
a transceiver; and
a processor configured to control the transceiver to perform time division duplex (TDD) based narrowband Internet of Things (NB-IoT) operations, the TDD based NB-IoT operations comprising:
configuring a search space for narrowband physical downlink control channel (NPDCCH) candidates each configured with one or more narrowband control channel elements (NCCEs) based on a corresponding aggregation level (AL); and
transmitting an NPDCCH signal, in a corresponding subframe, based on the configured search space,
wherein, in transmitting the NPDCCH signal,
based on that the corresponding subframe is a TDD special subframe between a downlink subframe and an uplink subframe, which includes a downlink pilot time slot (DwPTS), a guard period (GP) and an uplink pilot time slot (UpPTS), the NPDCCH signal is transmitted through a specific NPDCCH candidate in the TDD special subframe other than an AL-1 based NPDCCH candidate with 1-NCCE, and
wherein the AL-1 based NPDCCH candidate is not used for the NPDCCH signal only in the TDD special subframe.