Data transmission in an inactive state

Patent metadata

Field	Value
Publication number	US-12588097-B2
Application number	US-202217862263-A
Country	US
Kind code	B2
Filing date	Jul 11, 2022
Priority date	Aug 6, 2021
Publication date	Mar 24, 2026
Grant date	Mar 24, 2026

Abstract

The present application relates to small data transmission (SDT). In an example, SDT is available for transferring information between a UE and a network, where a NAS layer of the UE is in a 5GMM-CONNECTED mode with an RRC inactive indication and an AS layer of the UE is in an RRC_INACTIVE state. To do so, the UE can be pre-configured to classify the information as qualifying for SDT. In addition, resources can be pre-configured for the SDT. For instance, the UE can maintain a set of radio bearers in a suspended state. While the NAS layer is in the 5GMM-CONNECTED mode with the inactive indication and the AS layer is in the RRC_INACTIVE state, one or more of the pre-configured resources can be used to transmit the information between the UE and the network.

First claim

The invention claimed is:

1 . A method comprising:
processing, at a user equipment (UE) side device, while operating in a fifth generation mobility management (5GMM)-CONNECTED mode with a radio resource control (RRC) inactive indication and in a RRC_INACTIVE state, a paging message of a network, the paging message indicating that transmission of downlink data is available and is to use one or more radio bearers configured for small data transmission (SDT); initiating, at the UE side device, while operating in the 5GMM-CONNECTED mode with the RRC inactive indication and in the RRC_INACTIVE state, reception of the downlink data based on the paging message and a configuration, wherein the configuration is defined in association with the 5GMM-CONNECTED mode with the RRC inactive indication and with the RRC_INACTIVE state and indicates the one or more radio bearers to use for the reception; determining, at the UE side device, after the downlink data is received, to continue operating in the 5GMM-CONNECTED mode with the RRC inactive indication and in the RRC_INACTIVE state; processing, at the UE side device, a service accept message associated with a service request for transmitting data; determining, at the UE side device, based on the service accept message, that the RRC_INACTIVE state is to be maintained; and continuing, at the UE side device, to operate in the 5GMM-CONNECTED mode with the RRC inactive indication and in the RRC_INACTIVE state.

2 . The method of claim 1 , further comprising:
processing, while operating in the 5GMM-CONNECTED mode and prior to a transition to the 5GMM-CONNECTED mode with the RRC inactive indication and a transition to the RRC_INACTIVE state, the configuration from the network, wherein the configuration is indicated by an access stratum (AS) layer to a non-access stratum (NAS) layer.

3 . The method of claim 1 , wherein the configuration indicates at least one of: an information size, an information priority, or a number of radio bearers to which the configuration applies.

4 . The method of claim 1 , further comprising:
causing a signaling radio bearer zero (SRB0) to remain in an active state; causing, a signaling radio bearer other than SRB0 to transition to a suspended state; and causing a data radio bearer (DRB), to transition to the suspended state.

5 . The method of claim 1 , further comprising:
determining a first trigger to transfer uplink data; determining that the uplink data has a classification associated with the configuration; and causing, while in the RRC_INACTIVE state, a transmission of the uplink data on a data radio bearer (DRB).

6 . The method of claim 1 , further comprising:
determining that a data radio bearer (DRB) is unavailable to transmit uplink data; initiating a service request procedure corresponding to the service request; transitioning to an RRC_CONNECTED state; processing the service accept message based on the service request procedure, wherein the service accept message indicates that the RRC INACTIVE state is to be maintained; and remaining in the 5GMM-CONNECTED mode with the RRC inactive indication.

7 . The method of claim 1 , further comprising:
determining a trigger to transfer non access stratum (NAS) signaling information; determining that the NAS signaling information has a classification associated with the configuration; and causing, while in the RRC_INACTIVE state, a transmission of the NAS signaling information on a signaling radio bearer (SRB).

8 . The method of claim 1 , further comprising:
transitioning a data radio bearer (DRB) from a suspended state to a resumed state, wherein the downlink data is received on the DRB.

9 . One or more non-transitory computer-readable media storing instructions that, upon execution operations comprising:
Processing, at a user equipment (UE) side device, while a non-access stratum (NAS) layer is in a fifth generation mobility management (5GMM)-CONNECTED mode with a radio resource control (RRC) inactive indication and an access stratum (AS) layer of a user equipment (UE) is in a RRC_INACTIVE state, a paging message of a network, the paging message indicating that transmission of downlink data is available and is to use one or more radio bearers configured for small data transmission (SDT); initiating, at the UE side device, while the NAS layer is in the 5GMM-CONNECTED mode with the RRC inactive indication and the AS layer is in the RRC_INACTIVE state, reception of the downlink data based on the paging message and a configuration, wherein the configuration is defined in association with the 5GMM-CONNECTED mode with the RRC inactive indication and with the RRC_INACTIVE state and indicates the one or more radio bearers to use for the reception; determining, at the UE side device, after the downlink data is received, that the NAS layer is to remain in the 5GMM-CONNECTED mode with the RRC inactive indication and the AS layer is to remain in the RRC_INACTIVE state; processing, at the UE side device, a service accept message associated with a service request for transmitting data; determining, at the UE side device, based on the service accept message, that the RRC_INACTIVE state is to be maintained; and maintaining, at the UE side device, the NAS layer in the 5GMM-CONNECTED mode with the RRC inactive indication and the AS layer in the RRC_INACTIVE state.

10 . The one or more non-transitory computer-readable media of claim 9 , wherein the operations further comprise:
determining that uplink data is to be transmitted to the network, wherein the uplink data has a different classification that is unassociated with the configuration; determining that a data radio bearer (DRB) is available for a transmission of the uplink data, wherein the DRB is in a suspended state; transitioning the DRB to a resumed state; and transmitting, while the NAS layer is in the 5GMM-CONNECTED mode with the RRC inactive indication and the AS layer is in the RRC_INACTIVE state, the uplink data on the DRB.

11 . The one or more non-transitory computer-readable media of claim 9 , wherein the operations further comprise:
determining that uplink data is to be transmitted to the network, wherein the uplink data has a different classification that is unassociated with the configuration; determining that a data radio bearer (DRB) is unavailable for a transmission of the uplink data; transitioning the AS layer to an RRC CONNECTED state; and transmitting, while the NAS layer is in the 5GMM-CONNECTED mode and the AS layer is in the RRC_CONNECTED state, the uplink data.

12 . The one or more non-transitory computer-readable media of claim 9 , wherein the operations further comprise:
determining that uplink data is to be transmitted to the network, wherein the uplink data has a different classification that is unassociated with the configuration; and transmitting, to the network while the NAS layer is in the 5GMM-CONNECTED mode with the RRC inactive indication and the AS layer is in the RRC_INACTIVE state, the uplink data based on a unified access control (UAC) parameter.

13 . The one or more non-transitory computer-readable media of claim 9 , wherein the operations further comprise:
determining that uplink data is to be transmitted to the network, wherein the uplink data has a different classification that is unassociated with the configuration; causing, by the AS layer of the UE while the NAS layer is in the 5GMM-CONNECTED mode with the RRC inactive indication and the AS layer is in the RRC INACTIVE state, a transmission of the uplink data; determining, by the AS layer, a failure of the transmission; and causin

Assignees

• Apple Inc

Inventors

• Gupta Vivek G
• Prakasam Sridhar

Classifications

• H04W68/005

  Transmission of information for alerting of incoming communication · CPC title

• H04W76/30

  Connection release · CPC title

• H04W76/27 Primary

  Transitions between radio resource control [RRC] states · CPC title