Preamble sequence configuration method, user equipment, and access network device

1. A preamble sequence configuration method, comprising:

determining, by an access network device, preamble sequence information, wherein the preamble sequence information comprises a message indicating a quantity of preamble sequences, the preamble sequences are across a time domain, a frequency domain, and a code domain in a preamble sequence space, and the preamble sequence space further comprises a plurality of layers of code domain space in the code domain, and

wherein determining the preamble sequence information comprises determining space level information that indicates a quantity of code domain space layers of the preamble sequence space;

including, by the access network device, the space level information in the preamble sequence information; and

sending, by the access network device, the preamble sequence information to user equipment, wherein the preamble sequence information comprises the space level information and is used by the user equipment for random access.

2. The preamble sequence configuration method according to claim 1 , wherein the quantity of preamble sequences is a product of the quantity of code domain space layers of preamble sequence space and a quantity of preamble sequences in a layer of time-frequency resource.

3. The preamble sequence configuration method according to claim 1 , wherein including, by the access network device, the space level information in the preamble sequence information and sending, by the access network device, the preamble sequence information to user equipment comprise:

generating, by the access network device, a cyclic redundancy check (CRC) code based on the space level information;

performing, by the access network device, check processing on a master system information block (MIB) based on the CRC code; and

sending, by the access network device over a physical broadcast channel (PBCH), the MIB that has undergone the check processing.

4. The preamble sequence configuration method according to claim 1 , wherein including, by the access network device, the space level information in the preamble sequence information and sending, by the access network device, the preamble sequence information to user equipment comprise:

generating, by the access network device, a scrambling code sequence based on the space level information;

performing, by the access network device, scrambling processing on a MIB based on the scrambling code sequence; and

sending, by the access network device over a PBCH, the MIB that has undergone scrambling processing.

5. The preamble sequence configuration method according to claim 1 , wherein including, by the access network device, the space level information in the preamble sequence information and sending, by the access network device, the preamble sequence information to user equipment comprise:

adding, by the access network device, the space level information in the preamble sequence information to a system information block (SIB); and

sending, by the access network device, the SIB over a physical downlink shared channel (PDSCH).

6. The preamble sequence configuration method according to claim 5 , wherein the preamble sequence information further comprises time-frequency resource information, and the time-frequency resource information indicates a time-frequency resource across the time domain, and the frequency domain occupied by the preamble sequence space on a physical random access channel (PRACH); and

the sending, by the access network device, the preamble sequence information to user equipment further comprises:

adding, by the access network device, the time-frequency resource information in the preamble sequence information to the SIB; and

sending, by the access network device, the SIB over the PDSCH.

7. A preamble sequence configuration method, comprising:

obtaining, by user equipment, preamble sequence information sent by an access network device, wherein the preamble sequence information comprises a message indicating a quantity of preamble sequences, the preamble sequences are across a time domain, a frequency domain, and a code domain in a preamble sequence space, and the preamble sequence space further comprises a plurality of layers of code domain space in the code domain, and wherein the preamble sequence information comprises space level information that indicates a quantity of code domain space layers of the preamble sequence space;

obtaining, by the user equipment, the space level information in the preamble sequence information; and

performing, by the user equipment, random access based on the preamble sequence information.

8. The preamble sequence configuration method according to claim 7 , wherein the quantity of preamble sequences is a product of the quantity of code domain space layers of preamble sequence space and a quantity of preamble sequences in a layer of time-frequency resource.

9. The preamble sequence configuration method according to claim 7 , wherein obtaining, by user equipment, preamble sequence information sent by an access network device and obtaining, by the user equipment, the space level information in the preamble sequence information comprise:

performing, by the user equipment, blind detection on a physical broadcast channel (PBCH) to obtain a master system information block (MIB); and

determining the space level information based on a cyclic redundancy check (CRC) code removed during the blind detection.

10. The preamble sequence configuration method according to claim 7 , wherein obtaining, by user equipment, preamble sequence information sent by an access network device and obtaining, by the user equipment, the space level information in the preamble sequence information comprise:

performing, by the user equipment, blind detection on a PBCH to obtain a MIB; and

determining the space level information based on a decoding sequence used during the blind detection.

11. The preamble sequence configuration method according to claim 7 , wherein obtaining, by user equipment, preamble sequence information sent by an access network device and obtaining, by the user equipment, the space level information in the preamble sequence information comprise:

receiving, by the user equipment over a physical downlink shared channel (PDSCH), a system information block (SIB) sent by the access network device, wherein the SIB carries the space level information in the preamble sequence information; and

parsing, by the user equipment, the SIB to obtain the space level information.

12. The preamble sequence configuration method according to claim 11 , wherein the preamble sequence information further comprises time-frequency resource information, and the time-frequency resource information indicates a time-frequency resource across the time domain, and the frequency domain occupied by the preamble sequence space on a physical random access channel (PRACH); and

the obtaining, by user equipment, preamble sequence information sent by an access network device further comprises:

receiving, by the user equipment over the PDSCH, the SIB sent by the access network device, wherein the SIB carries the time-frequency resource information in the preamble sequence information; and

parsing, by the user equipment, the SIB to obtain the time-frequency resource information.

13. User equipment, comprising:

a receiver;

at least one processor coupled to the receiver; and

a non-transitory computer-readable storage medium coupled to the at least one processor and storing programming instructions for execution by the at least one processor;

wherein the receiver is configured to obtain preamble sequence information sent by an access network device, wherein the preamble sequence information comprises a message indicating a quantity of preamble sequences, the preamble sequences are across a time domain, a frequency domain, and a code domain in a preamble sequence space, and the preamble sequence space further comprises a plurality of layers of code domain space in the code domain, and wherein the preamble sequence information comprises space level information that indicates a quantity of code domain space layers of the preamble sequence space;

wherein the receiver is configured to further obtain the space level information in the preamble sequence information; and

wherein the programming instructions instruct the at least one processor to perform random access based on the preamble sequence information.

14. The user equipment according to claim 13 , wherein

the receiver is specifically configured to:

perform blind detection on a physical broadcast channel (PBCH) to obtain a master system information block (MIB); and

determine the space level information based on a cyclic redundancy check (CRC) code removed during the blind detection.

15. The user equipment according to claim 13 , wherein the receiver is specifically configured to:

perform blind detection on a PBCH to obtain a MIB; and

determine the space level information based on a decoding sequence used during the blind detection.

16. The user equipment according to claim 13 ,

the receiver is configured to receive, over a physical downlink shared channel (PDSCH), a system information block (SIB) sent by the access network device, wherein the SIB carries the space level information in the preamble sequence information; and

the receiver is further configured to parse the SIB to obtain the space level information.

17. The user equipment according to claim 16 , wherein the preamble sequence information further comprises time-frequency resource information, and the time-frequency resource information indicates a time-frequency resource across the time domain, and the frequency domain occupied by the preamble sequence space on a physical random access channel (PRACH);

the receiver is further configured to receive, over the PDSCH, the SIB sent by the access network device, wherein the SIB carries the time-frequency resource information in the preamble sequence information; and

the receiver is further configured to parse the SIB to obtain the time-frequency resource information.

18. The user equipment according to claim 13 , wherein the quantity of preamble sequences is a product of the quantity of code domain space layers of preamble sequence space and a quantity of preamble sequences in a layer of time-frequency resource.