Granted Patent B2

US 12,402,172 · App. 17/624,221 · Granted Aug 26, 2025

Inventor: Xiandong Dong (Beijing, CN)

Assignee: BEIJING XIAOMI MOBILE SOFTWARE CO., LTD.

H04W74/0833

Abstract

Claims (46)

1. A method for random access, comprising:

sending, by a terminal, according to a system message sent by an access network device, a preamble in a random access message on a first time-frequency resource and a payload in the random access message on a second time-frequency resource, wherein the system message includes first resource indication information and second resource indication information, the first resource indication information is used for indicating to the terminal the first time-frequency resource for sending the preamble in the random access message, and the second resource indication information is used for indicating to the terminal the second time-frequency resource for sending the payload in the random access message; wherein sending the payload in the random access message on the second time-frequency resource, comprises:

determining, in response to the terminal being in a radio resource control connection (RRC_connected) status or a radio resource control inactive (RRC_inactive) status, that a Cell Radio Network Temporary Identifier (C-RNTI) has been stored in the terminal, generating, by the terminal, a first payload comprising the C-RNTI, and sending to the access network device the first payload of the random access message on the second time-frequency resource, wherein the first payload is configured to inform the access network device that there is no need to allocate the C-RNTI to the terminal; and

determining, in response to the terminal being in a radio resource control idle (RRC_idle) status or an initial access status, that the terminal does not store the C-RNTI, generating, by the terminal, a second payload excluding the C-RNTI, and sending to the access network device the second payload of the random access message on the second time-frequency resource, wherein the second payload is configured to inform the access network device to allocate the C-RNTI to the terminal;

acquiring, by the terminal, a random access response message fed back by the access network device, wherein, when the terminal sends the second payload excluding the C-RNTI to the access network device, the random access response message acquired is a first random access response message comprising the C-RNTI; when the terminal sends the first payload comprising the C-RNTI to the access network device, the random access response message acquired is a second random access response message excluding the C-RNTI; and

determining, in response to a first terminal identifier in the random access response message being equal to a second terminal identifier of the terminal, whether to send an acknowledgement message to the access network device depending on whether the random access response message comprises the C-RNTI, wherein the acknowledgement message informs the access network device that the terminal has received the C-RNTI,

wherein determining whether to send the acknowledgement message to the access network device depending on whether the random access response message comprises the C-RNTI, comprises:

determining, by the terminal, in response to the random access response message being the first random access response message comprising the C-RNTI, to send the acknowledgement message to the access network device;

determining, by the terminal, in response to the random access response message being the second random access response message excluding the C-RNTI, not to send the acknowledgement message to the access network device;

wherein in response to the payload in the random access message being the first payload comprising the C-RNTI, the terminal acquiring the random access response message fed back by the access network device comprises:

descrambling, by the terminal, a scrambled physical downlink control channel (PDCCH) according to the C-RNTI, wherein the scrambled PDCCH is scrambled by the access network device according to the C-RNTI; and

receiving, in response to successful descrambling of the scrambled PDCCH, by the terminal, the random access response message according to first indication information transmitted on the descrambled PDCCH.

2. A method for random access, comprising:

sending, by an access network device, a system message to a terminal, wherein the system message includes first resource indication information and second resource indication information, the first resource indication information is used for indicating to the terminal a first time-frequency resource for sending a preamble in a random access message, and the second resource indication information is used for indicating to the terminal a second time-frequency resource for sending a payload in the random access message;

receiving, by the access network device, the preamble on the first time-frequency resource, and receiving the payload on the second time-frequency resource, wherein receiving the payload on the second time-frequency resource comprises:

in response to the terminal being in a radio resource control connection RRC_connected) status or a radio resource control inactive (RRC_inactive) status, receiving a first payload comprising a Cell Radio Network Temporary Identifier (C-RNTI) on the second time-frequency resource, wherein the C-RNTI has been stored in the terminal and the first payload is configured to inform the access network device that there is no need to allocate the C-RNTI to the terminal;

in response to the terminal being in a radio resource control idle (RRC_idle) status or an initial access status, receiving a second payload excluding the C-RNTI on the second time-frequency resource, wherein the terminal does not store the C-RNTI, and the second payload is configured to inform the access network device to allocate the C-RNTI to the terminal; and

generating, by the access network device, a random access response message according to whether the payload carries the C-RNTI, wherein

the random access response message comprises a first terminal identifier used for the terminal to determine whether the first terminal identifier is equal to a second terminal identifier of the terminal, or

the random access response message comprises the first terminal identifier and the C-RNTI;

wherein, when the random access response message comprises the first terminal identifier and the C-RNTI, the method further comprises:

receiving, by the access network device, an acknowledgement message from the terminal, wherein the acknowledgement message informs the access network device that the terminal has received the C-RNTI;

wherein the access network device generating the random access response message according to whether the payload carries the C-RNTI, comprises:

allocating, in response to the payload of the random access message being the second payload excluding the C-RNTI, by the access network device, the C-RNTI to the terminal, and generating a first random access response message comprising the C-RNTI, wherein the first random access response message serves as the random access response message; and

generating, in response to the payload of the random access message being the first payload comprising the C-RNTI, by the access network device, a second random access response message excluding the C-RNTI, wherein the second random access response message serves as the random access response message; and

wherein in response to the payload being the first payload comprising the C-RNTI, the method further comprises:

scrambling, by the access network device, a physical downlink control channel (PDCCH) according to the C-RNTI; and

transmitting, by the access network device, first indication information on the scrambled PDCCH, wherein the first indication information is used for indicating the terminal to receive the random access response message.

3. A terminal, comprising:

one or more processors; and

a memory for storing one or more executable instructions of the one or more processors, wherein the one or more processors are configured to:

send, according to a system message sent by an access network device, a preamble in a random access message on a first time-frequency resource and a payload in the random access message on a second time-frequency resource, wherein the system message includes first resource indication information and second resource indication information, the first resource indication information is used for indicating to the terminal the first time-frequency resource for sending the preamble in the random access message, and the second resource indication information is used for indicating to the terminal the second time-frequency resource for sending the payload in the random access message;

acquire a random access response message fed back by the access network device, wherein, when the terminal sends a second payload excluding a Cell Radio Network Temporary Identifier (C-RNTI) to the access network device, the random access response message acquired is a first random access response message comprising the C-RNTI; when the terminal sends a first payload comprising the C-RNTI to the access network device, the random access response message acquired is a second random access response message excluding the C-RNTI; and

determine, in response to a first terminal identifier in the random access response message being equal to a second terminal identifier of the terminal, whether to send an acknowledgement message to the access network device depending on whether the random access response message comprises the C-RNTI, wherein the acknowledgement message informs the access network device that the terminal has received the C-RNTI;

wherein the one or more processors are further configured to:

determine, in response to the terminal being in a radio resource control connection (RRC_connected) status or a radio resource control inactive (RRC_inactive) status, that the C-RNTI has been stored in the terminal, generate the first payload comprising the C-RNTI, and send to the access network device the first payload of the random access message on the second time-frequency resource, wherein the first payload is configured to inform the access network device that there is no need to allocate the C-RNTI to the terminal;

determine, in response to the terminal being in a radio resource control idle (RRC_idle) status or an initial access status, that the terminal does not store the C-RNTI, generate the second payload excluding the C-RNTI, and send to the access network device the second payload of the random access message on the second time-frequency resource, wherein the second payload is configured to inform the access network device to allocate the C-RNTI to the terminal;

wherein, in response to the payload in the random access message being the first payload comprising the C-RNTI, the one or more processors are further configured to:

descramble a scrambled physical downlink control channel (PDCCH) according to the C-RNTI, wherein the scrambled PDCCH is scrambled by the access network device according to the C-RNTI; and

receive, in response to successful descrambling of the scrambled PDCCH, the random access response message according to first indication information transmitted on the descrambled PDCCH; and

wherein the one or more processors are further configured to:

determine, in response to the random access response message being the first random access response comprising the C-RNTI, to send the acknowledgement message to the access network device;

determining, in response to the random access response message being the second random access response excluding the C-RNTI, not to send the acknowledgement message to the access network device.

4. An access network device, comprising:

one or more processors; and

a memory for storing one or more executable instructions of the one or more processors, wherein the one or more processors are configured to implement the random access method of claim 2 .

Assignments (1)

Continuity (1)

References Cited (29)