Redcap UE fallback
A method for wireless communication at a user equipment (UE) and related apparatus are provided. In the method, the UE identify, based on a support of a cell for the UE operating with reduced capability, a cell type of the cell. The cell type is one of a reduced capability (RC) type, a fallback (FB) type, or a neither (N) type, corresponding to various support for the UE operating with the reduced capability. The UE further configures a device mode, where the device mode includes an RC mode or a FB-allowed mode, and manages the connection between the UE and the cell based on the device mode and the cell type.
1 . An apparatus of wireless communication at a user equipment (UE), comprising:
at least one memory; and
at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor is configured to:
identify, based on a support of a cell for the UE operating with reduced capability, a cell type of the cell, wherein the cell type is one of a reduced capability (RC) type, a fallback (FB) type, or a neither (N) type, wherein the RC type indicates a full support for the UE operating with the reduced capability, the FB type indicates a compatible support for the UE operating with the reduced capability and a support for establishing a connection with the UE operating with the reduced capability, and the N type indicates a lack of the support for the UE operating with the reduced capability and a lack of the support for establishing the connection with the UE operating with the reduced capability;
configure a device mode of the UE, wherein the device mode includes an RC mode or a FB-allowed mode; and
manage, based on the device mode of the UE, a capability state of the UE, and the cell type, the connection between the UE and the cell, wherein the capability state is associated with the device mode of the UE, and the capability state includes an RC state indicating an activation of the UE operating with the reduced capability and a non-RC (NRC) state indicating an enablement of the UE connecting with a target cell of the FB type.
2 . The apparatus of claim 1 , wherein the at least one processor is further configured to:
output an indication of the managed connection between the UE and the cell.
3 . The apparatus of claim 1 , wherein the reduced capability includes one of:
an operational frequency bandwidth of the UE limited by a bandwidth threshold,
a number of data radio bearers (DRB) limited by a DRB threshold, or
a length of a sequence number used in radio link control (RLC) and packet data convergence protocol (PDCP) layers limited by a length threshold.
4 . The apparatus of claim 3 , wherein the RC mode indicates the UE operating with the reduced capability, and wherein the FB-allowed mode indicates the enablement of the UE connecting with the target cell of the FB type.
5 . The apparatus of claim 4 , wherein the at least one processor is further configured to:
receive a mode configuration indicating the device mode, and wherein to configure the device mode of the UE, the at least one processor is configured to:
configure, based on the mode configuration, the device mode of the UE.
6 . The apparatus of claim 4 , wherein the at least one processor is further configured to:
store a set of network identifiers, wherein each network identifier of the set of network identifiers has an associated device mode, and wherein to configure the device mode of the UE, the at least one processor is configured to:
configure the device mode of the UE based on an association of the cell with the set of network identifiers.
7 . The apparatus of claim 6 , wherein each network identifier of the set of network identifiers includes one or more of:
a public land mobile network (PLMN),
a mobile country code, or
a network operator.
8 . The apparatus of claim 3 , wherein to configure the device mode of the UE, the at least one processor is configured to:
configure the device mode of the UE as the FB-allowed mode, and wherein the at least one processor is further configured to:
update the capability state of the UE.
9 . The apparatus of claim 8 , wherein to manage the connection between the UE and the cell, the at least one processor is configured to:
manage a mobility procedure of the UE with respect to a plurality of cells.
10 . The apparatus of claim 9 , wherein the cell is a first cell, and wherein the mobility procedure of the UE includes:
a reselection process for selecting a second cell from the plurality of cells for the UE,
a redirection process for selecting the second cell for the UE,
a connected mode measurement process for selecting the second cell for the UE,
a handover for selecting the second cell for the UE,
an out-of-service (OOS) scan for selecting the second cell for the UE,
a radio link failure (RLF) scan for selecting the second cell for the UE, or
a power scan for selecting the second cell for the UE.
11 . The apparatus of claim 10 , wherein to update the capability state of the UE, the at least one processor is configured to:
update, via a mobility registration update, the capability state of the UE.
12 . The apparatus of claim 10 , wherein to update the capability state of the UE, the at least one processor is configured to:
switch, in response to a first condition associated with the UE being met, the capability state of the UE from the RC state to the NRC state, or
switch, in response to a second condition associated with the UE being met, the capability state of the UE from the NRC state to the RC state.
13 . The apparatus of claim 12 , wherein the first condition includes one or more of:
the UE determining, based on system information block type 1 (SIB1) of the second cell, the second cell is not the RC type,
the UE including an out-of-service (OOS) duration longer than a first time threshold,
the UE identifying no cell in the plurality of cells as having the cell type of the RC type or a long-term evolution (LTE) type during a radio link failure (RLF) recovery process, and the UE identifying a first number of cells of an NRC type in the plurality of cells, the first number greater than a first counter threshold, or
the UE connecting with an LTE cell of the LTE type for longer than a second time threshold, and a second number of neighbor cells of the NRC type in the plurality of cells being available, the second number greater than the first counter threshold.
14 . The apparatus of claim 12 , wherein the second condition includes one or more of:
the UE determining, based on system information block type 1 (SIB1) of the second cell, the second cell is the RC type,
the UE being connected with an LTE cell of a long-term evolution (LTE) type in the plurality of cells, and a number of available cells of the RC type in the plurality of cells being larger than a first threshold, or
the UE being connected with an RC cell of the RC type in the plurality of cells, and the number of available cells of the RC type in the plurality of cells being larger than the first threshold.
15 . The apparatus of claim 12 , wherein to update the capability state of the UE, the at least one processor is configured to:
set the capability state of the UE to the RC state, and wherein to manage the mobility procedure of the UE, the at least one processor is configured to:
assign a priority for each cell of the plurality of cells based on the cell type of each cell, and wherein a first priority for the RC type is higher than a second priority for a long-term evolution (LTE) type; and
manage, in response to the second cell being one of the RC type or the LTE type, the mobility procedure of the UE based on the priority of the second cell.
16 . The apparatus of claim 12 , wherein to update the capability state of the UE, the at least one processor is configured to:
set the capability state of the UE to the NRC state, and wherein to manage the mobility procedure of the UE, the at least one processor is configured to:
assign a priority for each cell of the plurality of cells based on the cell type of each cell, and wherein a first priority for the RC type is higher than a second priority for an NRC type, the second priority is higher than a third priority for an frequency division duplex (FDD) type, the third priority is higher than a fourth priority for a time division duplex (TDD) type, and the fourth priority is higher than a fifth priority for a long-term evolution (LTE) type; and
manage the mobility procedure of the UE based on the priority for each cell of the plurality of cells.
17 . The apparatus of claim 16 , wherein to manage the mobility procedure of the UE, the at least one processor is configured to:
limit, in response to a failure of the mobility procedure of the UE, an access of the UE to one or more cells of the plurality of cells associated with a band for a first period of time.
18 . An apparatus of wireless communication at a network node, comprising:
at least one memory; and
at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor is configured to:
configure, based on a user equipment (UE) operating with a reduced capability, a communication setting for the network node accommodating the reduced capability of the UE, wherein the communication setting reduces a communication capability of the network node; and
communicate, based on the communication setting, a capability state of the UE, and a device mode of the UE, with the UE, wherein the device mode includes a reduced capability (RC) mode or a fallback (FB)-allowed mode, wherein the capability state is associated with the device mode of the UE, and the capability state includes an RC state indicating an activation of the UE operating with the reduced capability and a non-RC (NRC) state indicating an enablement of the UE connecting with a target cell of the FB type.
19 . The apparatus of claim 18 , wherein the reduced capability of the UE includes one of:
an operational frequency bandwidth of the UE limited by a bandwidth threshold,
a number of data radio bearers (DRB) limited by a DRB threshold, or
a length of a sequence number used in radio link control (RLC) and packet data convergence protocol (PDCP) layers limited by a length threshold.
20 . A method of wireless communication at a user equipment (UE), comprising:
identifying, based on a support of a cell for the UE operating with reduced capability, a cell type of the cell, wherein the cell type is one of a reduced capability (RC) type, a fallback (FB) type, or a neither (N) type, wherein the RC type indicates a full support for the UE operating with the reduced capability, the FB type indicates a compatible support for the UE operating with the reduced capability and a support for establishing a connection with the UE operating with the reduced capability, and the N type indicates a lack of the support for the UE operating with the reduced capability and a lack of the support for establishing the connection with the UE operating with the reduced capability;
configuring a device mode of the UE, wherein the device mode includes an RC mode or a FB-allowed mode; and
managing, based on the device mode of the UE, a capability state of the UE, and the cell type, the connection between the UE and the cell, wherein the capability state is associated with the device mode of the UE, and the capability state includes an RC state indicating an activation of the UE operating with the reduced capability and a non-RC (NRC) state indicating an enablement of the UE connecting with a target cell of the FB type.