Method of transmitting and receiving broadcasting channel and device therefor
The present disclosure provides a method of transmitting a Physical Broadcasting Channel (PBCH) by a base station in a wireless communication system. Particularly, the method may include generating a PBCH payload including bits indicating a frame in which the PBCH is transmitted; scrambling at least some of the bits included in the PBCH payload using second and third least significant bits among the bits; and transmitting the bits of the PBCH payload including the at least some scrambled bits to a user equipment.
1. A method for transmitting a physical broadcast channel (PBCH) by a base station (BS) in a wireless communication system, the method comprising:
obtaining first scrambled bits by scrambling a bit sequence of a PBCH payload based on a first scrambling sequence, wherein the PBCH payload includes information about system frame number (SFN) about a frame in which the PBCH is transmitted;
obtaining second scrambled bits based on the first scrambled bits and a second scrambling sequence;
obtaining the PBCH based on the second scrambled bits; and
transmitting, to a user equipment, (i) the PBCH and (ii) a demodulation reference signal (DMRS) for the PBCH,
wherein the first scrambling sequence is obtained based on a 2 nd and 3 rd least significant bits of the SFN in which the PBCH is transmitted, and
wherein the second scrambling sequence and a sequence of the DMRS are obtained based on same bits of an index of a synchronization signal/PBCH block (SS/PBCH block) including the PBCH.
2. The method of claim 1 ,
wherein the first and second scrambling sequences are obtained further based on an identifier of a cell related to the BS.
3. The method of claim 1 ,
wherein bits of the PBCH payload corresponding to the 2 nd and the 3 rd least significant bits of the SFN are not scrambled.
4. The method of claim 1 ,
wherein encoded bits are obtained by channel coding based on the first scrambled bits, and the second scrambled bits are obtained by scrambling the encoded bits based on the second scrambling sequence.
5. The method of claim 1 ,
wherein the second scrambling sequence and the sequence of the DMRS are obtained based on 3 bits of the index of the SS/PBCH block.
6. A base station (BS) for transmitting a physical broadcast channel (PBCH) in a wireless communication system, the BS comprising:
at least one transceiver;
at least one processor; and
at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations comprising:
obtaining first scrambled bits by scrambling a bit sequence of a PBCH payload based on a first scrambling sequence, wherein the PBCH payload includes information about system frame number (SFN) about a frame in which the PBCH is transmitted;
obtaining second scrambled bits based on the first scrambled bits and a second scrambling sequence;
obtaining the PBCH based on the second scrambled bits; and
transmitting, to a user equipment, (i) the PBCH and (ii) a demodulation reference signal (DMRS) for the PBCH,
wherein the first scrambling sequence is obtained based on a 2 nd and 3 rd least significant bits of the SFN in which the PBCH is transmitted, and
wherein the second scrambling sequence and a sequence of the DMRS are obtained based on same bits of an index of a synchronization signal/PBCH block (SS/PBCH block) including the PBCH.
7. The BS of claim 6 ,
wherein the first and second scrambling sequences are generated further based on an identifier of a cell related to the BS.
8. The BS of claim 6 ,
wherein bits of the PBCH payload corresponding to the 2 nd and the 3 rd least significant bits of the SFN are not scrambled.
9. The BS of claim 6 ,
wherein encoded bits are obtained by channel coding based on the first scrambled bits, and the second scrambled bits are obtained by scrambling the encoded bits based on the second scrambling sequence.
10. The BS of claim 6 ,
wherein the second scrambling sequence and a sequence of the DMRS are obtained based on 3 bits of the index of the SS/PBCH block.
11. A method for receiving a physical broadcast channel (PBCH) by a user equipment (UE) in a wireless communication system, the method comprising:
receiving, from a base station (BS), a synchronization signal/PBCH block (SS/PBCH block) including the PBCH and a demodulation reference signal (DMRS) for the PBCH;
obtaining information about an index of the SS/PBCH block;
based on a second scrambling sequence and second scrambled bits included in the PBCH, obtaining i) first scrambled bits and ii) 2 nd and 3 rd least significant bits of System Frame Number (SFN) about a frame in which the PBCH is transmitted, and
obtaining a PBCH payload including information about the SFN by descrambling the first scrambled bits based on a first scrambling sequence,
wherein the first scrambling sequence is obtained based on the 2 nd and the 3 rd least significant bits of the SFN, and
wherein the second scrambling sequence and a sequence of the DMRS are obtained based on same bits of the index of the SS/PBCH block.
12. The method of claim 11 ,
wherein the first and second scrambling sequences are generated further based on an identifier of a cell related to the BS.
13. The method of claim 11 ,
wherein bits of the PBCH payload corresponding to the 2 nd and the 3 rd least significant bits of the SFN are not scrambled.
14. The method of claim 11 ,
wherein encoded bits are obtained by descrambling the second scrambled bits based on the second scrambling sequence, and the first scrambled bits are obtained by decoding the encoded bits.
15. The method of claim 11 ,
wherein the second scrambling sequence and a sequence of the DMRS are obtained based on 3 bits of the index of the SS/PBCH block.
16. A user equipment (UE) for receiving a physical broadcast channel (PBCH) in a wireless communication system, the UE comprising:
at least one transceiver;
at least one processor; and
at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations comprising:
receiving, from a base station (BS), a synchronization signal/PBCH block (SS/PBCH block) including the PBCH and a demodulation reference signal (DMRS) for the PBCH;
obtaining information about an index of the SS/PBCH block;
based on a second scrambling sequence and second scrambled bits included in the PBCH, obtaining i) first scrambled bits and ii) 2 nd and 3 rd least significant bits of System Frame Number (SFN) about a frame in which the PBCH is transmitted, and
obtaining a PBCH payload including information about the SFN by descrambling the first scrambled bits based on a first scrambling sequence,
wherein the first scrambling sequence is obtained based on the 2 nd and the 3 rd least significant bits of the SFN, and
wherein the second scrambling sequence and a sequence of the DMRS are obtained based on same bits of the index of the SS/PBCH block.
17. The UE of claim 16 ,
wherein the first and second scrambling sequences are generated further based on an identifier of a cell related to the BS.
18. The UE of claim 16 ,
wherein bits of the PBCH payload corresponding to the 2 nd and the 3 rd least significant bits of the SFN are not scrambled.
19. The UE of claim 16 ,
wherein encoded bits are obtained by descrambling the second scrambled bits based on the second scrambling sequence, and the first scrambled bits are obtained by decoding the encoded bits.
20. The UE of claim 16 ,
wherein the second scrambling sequence and a sequence of the DMRS are obtained based on 3 bits of the index of the SS/PBCH block.