Operation method of terminal and base station in wireless communication system supporting unlicensed band, and apparatus supporting same
The present disclosure provides an operation method of a terminal and a base station in a wireless communication system supporting an unlicensed band, and an apparatus supporting same. As a specific example, the present disclosure comprises an operation method of a terminal and an operation method of a base station corresponding thereto, by which a terminal can obtain timing information relating to a unlicensed band on the basis of a PBCH payload in a synchronization signal/physical broadcast channel (SS/PBCH) block and a demodulation reference signal (DMRS) sequence for the PBCH.
1. A method of a user equipment (UE) in a wireless communication system, the method comprising:
receiving a synchronization signal (SS)/physical broadcast channel (PBCH) block,
wherein the SS/PBCH block includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a PBCH,
acquiring timing information based on PBCH payload included in the PBCH and a demodulation reference signal (DMRS) sequence for the PBCH,
wherein a number of candidate positions of the SS/PBCH block and a number of bits of the PBCH payload used to acquire the timing information are determined differently based on a subcarrier spacing (SCS).
2. The method of claim 1 , wherein the number of candidate positions of the SS/PBCH block based on the SCS being 30 kHz is configured to twice the number of candidate positions of the SS/PBCH block based on the SCS being 15 kHz.
3. The method of claim 2 , wherein based on that the SCS being 15 kHz, the timing information is acquired based on 1-bit of the PBCH payload, and
wherein based on that the SCS being 30 kHz, the timing information is acquired based on 2-bit of the PBCH payload.
4. The method of claim 2 , wherein a time duration in which the number of candidate positions of the SS/PBCH block are configured is set equally irrespective of the SCS.
5. The method of claim 1 , wherein the timing information includes index information of the SS/PBCH block, and
wherein at least one of (i) a frame boundary, (ii) a slot boundary, (iii) a frame index, or (iv) a slot index is acquired based on the index information of the SS/PBCH block.
6. The method of claim 1 , wherein the DMRS sequence for the PBCH is configured to be associated with index of candidate of a plurality of SS/PBCH blocks in a specific time duration.
7. The method of claim 1 , wherein the UE detects related DMRS sequence information by blind-detecting the DMRS sequence for the PBCH, and
wherein the UE decodes the PBCH payload in the SS/PBCH block based on the DMRS sequence information.
8. The method of claim 1 , further comprising performing initial access to a base station (BS) based on (i) the acquired timing information and (ii) the received SS/PBCH block.
9. The method of claim 1 , wherein the SS/PBCH block is received at one of a plurality of candidate positions available for transmission of the SS/PBCH block in the unlicensed band.
10. A user equipment (UE) operating in a wireless communication system, the UE comprising:
at least one radio frequency (RF) module;
at least one processor; and
at least one memory operably coupled to the at least one processor and storing instructions which, when executed, cause the at least one processor to perform a specific operation,
wherein the specific operation includes:
receiving a synchronization signal (SS)/physical broadcast channel (PBCH) block,
wherein the SS/PBCH block includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a PBCH,
acquiring timing information based on PBCH payload included in the PBCH and a demodulation reference signal (DMRS) sequence for the PBCH,
wherein a number of candidate positions of the SS/PBCH block and a number of bits of the PBCH payload used to acquire the timing information are determined differently based on a subcarrier spacing (SCS).
11. The UE of claim 10 , wherein the UE communicates with at least one of a mobile terminal, a network, or an autonomous driving vehicle other than a vehicle including the UE.
12. A base station (BS) operating in a wireless communication system, the BS comprising:
at least one radio frequency (RF) module;
at least one processor; and
at least one memory operably coupled to the at least one processor and storing instructions which, when executed, cause the at least one processor to perform a specific operation,
wherein the specific operation includes:
performing a channel access procedure (CAP) for transmission of a synchronization signal (SS)/physical broadcast channel (PBCH) block; and
transmitting the SS/PBCH block to the UE based on the CAP, and
wherein the SS/PBCH block includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a PBCH, and
wherein timing information is acquired based on PBCH payload included in the PBCH and a demodulation reference signal (DMRS) sequence for the PBCH, and
wherein a number of candidate positions of the SS/PBCH block and a number of bits of the PBCH payload used to acquire the timing information are determined differently based on subcarrier spacing (SCS).
13. The BS of claim 12 , wherein the BS transmits the SS/PBCH block to the UE at one of a plurality of candidate positions available for transmission of the SS/PBCH block based on the CAP.