Uplink synchronization method and related device

1 . A method applied to a terminal device and comprising:

receiving, from a first network device via broadcasting, first system information and second system information;

generating a first random access preamble based on the first system information;

generating a second random access preamble based on the second system information;

sending, to a first network device through a normal uplink (NUL), first uplink data wherein the first uplink data comprises the first random access preamble of the NUL;

sending, to a second network device through a supplementary uplink (SUL), second uplink data, wherein the second uplink data comprises the second random access preamble of the SUL;

receiving, from the first network device, a first timing advance and a second timing advance, wherein the first timing advance is based on the first uplink data, and wherein the second timing advance is based on the second uplink data;

adjusting, based on the first timing advance, a first time for sending the first uplink data through the NUL; and

adjusting, based on the second timing advance, a second time for sending the second uplink data through the SUL.

2 . The method of claim 1 , wherein receiving the first timing advance and the second timing advance comprises receiving first downlink signaling, wherein the first downlink signaling carries the first timing advance and the second timing advance.

3 . The method of claim 2 , wherein receiving the first timing advance and the second timing advance comprises separately receiving second downlink signaling of the NUL and third downlink signaling of the SUL, wherein the second downlink signaling carries the first timing advance, and wherein the third downlink signaling carries the second timing advance.

4 . The method of claim 3 , wherein the first downlink signaling comprises a first media access control layer control element (MAC CE), wherein the second downlink signaling comprises a second MAC CE, and wherein the third downlink signaling comprises a third MAC CE.

5 . The method of claim 3 , wherein

the first downlink signaling comprises first random access response signaling, wherein the second downlink signaling comprises second random access response signaling of the NUL, and wherein the third downlink signaling comprises third random access response signaling of the SUL.

6 . The method of claim 1 , wherein before generating the first random access preamble and before generating the second random access preamble, the method further comprises:

receiving, from the first network device via broadcast, identification information;

generating the first random access preamble based on the first system information; and

generating, after receiving the identification information, the second random access preamble based on the second system information, wherein the identification information is at least one of a first identifier or a second identifier, wherein the first identifier indicates that the first network device and the second network device are in non-co-site deployment, and wherein the second identifier indicates that a timing advance (TA) of the NUL and a TA of the SUL are independently maintained.

7 . The method of claim 1 , further comprising:

sending the first random access preamble to the first network device through the NUL;

receiving a physical downlink control channel order from the first network device; and

sending, through the SUL and based on the physical downlink control channel order, the second random access preamble to the second network device.

8 . The method of claim 1 , wherein before sending the first uplink data and sending the second uplink data, the method further comprises:

sending, through the SUL, the second random access preamble to the second network device;

receiving a physical downlink control channel order from the first network device, wherein the physical downlink control channel order is indicated by the second network device to be delivered by the first network device; and

sending, through the NUL and based on the physical downlink control channel order, the first random access preamble to the first network device.

9 . The method of claim 1 , wherein the first system information is first system information block (SIB) information of the NUL, and wherein the second system information is second SIB information of the SUL.

10 . A method applied to a first network device and comprising:

sending identification information to a terminal device, wherein the identification information comprises at least one of a first identifier or a second identifier, wherein the first identifier indicates that the first network device and a second network device are in non-co-site deployment, and wherein the second identifier indicates that a timing advance (TA) of a normal uplink (NUL) and a TA of a supplementary uplink (SUL) are independently maintained;

receiving, from the terminal device through the NUL, first uplink data wherein the first uplink data comprises a first random access preamble of the NUL;

calculating a first timing advance based on the first uplink data;

receiving, from a second network device, a second timing advance, wherein the second timing advance is based on second uplink data from the terminal device, and wherein the second uplink data comprises a second random access preamble of the SUL; and

sending, to the terminal device, the first timing advance to adjust a first time for sending the first uplink data through the NUL and the second timing advance to adjust a second time for sending the second uplink data through the SUL.

11 . The method of claim 10 , wherein sending the first timing advance and the second timing advance to the terminal device comprises sending, to the terminal device, first downlink signaling, wherein the first downlink signaling carries the first timing advance and the second timing advance.

12 . The method of claim 11 , wherein sending the first timing advance and the second timing advance to the terminal device comprises separately sending, to the terminal device, second downlink signaling of the NUL and third downlink signaling of the SUL, wherein the second downlink signaling carries the first timing advance, and wherein the third downlink signaling carries the second timing advance.

13 . The method of claim 12 , wherein the first downlink signaling comprises a first media access control layer control element (MAC CE), wherein the second downlink signaling comprises a second MAC CE, and wherein the third downlink signaling comprises a third MAC CE.

14 . The method of claim 12 , wherein before receiving the first uplink data, the method further comprises:

obtaining, from the second network device, second system information; and

sending, to the terminal device, first system information to generate the first random access preamble and the second system information to generate the second random access preamble.

15 . The method of claim 12 , wherein the first downlink signaling comprises first random access response signaling, wherein the second downlink signaling comprises second random access response signaling of the NUL, and wherein the third downlink signaling comprises third random access response signaling of the SUL.

16 . The method of claim 14 , wherein the first system information is first system information block (SIB) information of the NUL, and wherein the second system information is second SIB information of the SUL.

17 . The method of claim 10 , wherein after receiving the first uplink data, the method further comprises sending a physical downlink control channel order to the terminal device, wherein the physical downlink control channel order instructs the terminal device to send the second random access preamble to the second network device through the SUL.

18 . The method of claim 10 , wherein before receiving the first uplink data, the method further comprises:

receiving, from the second network device, an indication message; and

sending, to the terminal device, a physical downlink control channel order based on the indication message, wherein the physical downlink control channel order instructs the terminal device to send the first random access preamble to the first network device through the NUL.

19 . The method of claim 10 , wherein before sending the first timing advance and the second timing advance to the terminal device, the method further comprises:

sending, to the second network device, a timing advance query request instructing the second network device to send the second timing advance to the first network device; and

receiving or periodically receiving, from the second network device, the second timing advance.

20 . An uplink synchronization method applied to a second network device, the method comprising:

sending second system information to a first network device;

receiving, from a terminal device through a supplementary uplink (SUL), second uplink data, wherein the second uplink data comprises a second random access preamble of the SUL, and wherein the second random access preamble is generated by the terminal device based on the second system information;

calculating a second timing advance based on the second uplink data;

sending, to a first network device, the second timing advance to adjust a time for sending uplink data through the SUL; and

receiving, from the terminal device, third uplink data through the SUL based on the second timing advance.