Method for transmitting or receiving synchronization signal block in unlicensed band, and apparatus therefor

An apparatus configured to receive a synchronization signal/physical broadcast channel (SS/PBCH) block in an unlicensed band, the apparatus comprising:

• at least one processor;
• and
• at least one memory operably connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations comprising:
• receiving the SS/PBCH block including a synchronization signal (SS) and a physical broadcast channel (PBCH);
• detecting an index of a demodulation reference signal (DMRS) sequence for the PBCH;
• and
• obtaining an index of the SS/PBCH block based on the index of the DMRS sequence,
• wherein a number of indices of SS/PBCH blocks is less than a number of indices of DMRS sequences, wherein the number of the indices of the DMRS sequences is 8,
• wherein the indices of the SS/PBCH blocks are cyclically mapped to the indices of the DMRS sequences,
• wherein the number of indices of the SS/PBCH blocks is equal to Q, wherein the Q is an interval between the SS/PBCH blocks where a quasi co-location (QCL) may be assumed,
• wherein actually transmitted SS/PBCH blocks among the SS/PBCH blocks are indicated by a bitmap indicating the indices of the SS/PBCH blocks,
• wherein, based on the Q, the bitmap of 8 bits is received, and only Q bits among the 8 bits of the bitmap are available to indicate the actually transmitted SS/PBCH blocks.

A user equipment (UE) configured to receive a synchronization signal/physical broadcast channel (SS/PBCH) block in an unlicensed band,

• at least one transceiver;
• at least one processor;
• and
• at least one memory operably connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations comprising:
• receiving the SS/PBCH block including a synchronization signal (SS) and a physical broadcast channel (PBCH) through the at least one transceiver;
• detecting an index of a demodulation reference signal (DMRS) sequence for the PBCH;
• and
• obtaining an index of the SS/PBCH block based on the index of the DMRS sequence,
• wherein a number of indices of SS/PBCH blocks is less than a number of indices of DMRS sequences, wherein the number of the indices of the DMRS sequences is 8,
• wherein the indices of the SS/PBCH blocks are cyclically mapped to the indices of the DMRS sequences,
• wherein the number of indices of the SS/PBCH blocks is equal to Q, wherein the Q is an interval between the SS/PBCH blocks where a quasi co-location (QCL) may be assumed,
• wherein actually transmitted SS/PBCH blocks among the SS/PBCH blocks are indicated by a bitmap indicating the indices of the SS/PBCH blocks,
• wherein, based on the Q, the bitmap of 8 bits is received, and only Q bits among the 8 bits of the bitmap are available to indicate the actually transmitted SS/PBCH blocks.