WO2021237547A1

WO2021237547A1 - Attach request for disabling new radio with dual subscriber identity modules

Info

Publication number: WO2021237547A1
Application number: PCT/CN2020/092771
Authority: WO
Inventors: Tianya LIN; Hao Zhang; Xiuqiu XIA
Original assignee: Qualcomm Incorporated
Priority date: 2020-05-28
Filing date: 2020-05-28
Publication date: 2021-12-02

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, by a first subscriber identity module (SIM) that is attached with New Radio (NR) service to a first cell, a tracking area update (TAU) rejection message from the first cell based at least in part on transmitting a TAU request that indicates no support for dual connectivity with NR (DCNR). The UE may add, for the first SIM, a public land mobile network (PLMN) associated with the first cell to a list of PLMNs. The UE may determine, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list and transmit, for the second SIM, an attach request to the second cell indicating no support for DCNR. Numerous other aspects are provided.

Description

ATTACH REQUEST FOR DISABLING NEW RADIO WITH DUAL SUBSCRIBER IDENTITY MODULES

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for disabling New Radio data service for dual subscriber identity modules with an attach request.

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and/or the like) . Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE) . LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP) .

A wireless communication network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs) . A user equipment (UE) may communicate with a base station (BS) via the downlink and uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a Node B, a gNB, an access point, a radio head, a transmit receive point (TRP) , a New Radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. New Radio (NR) , which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP) . NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL) , using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM) ) on the uplink (UL) , as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in LTE and NR technologies. Preferably, these improvements should be applicable to other multiple access technologies and the telecommunication standards that employ these technologies.

SUMMARY

In some aspects, a method of wireless communication, performed by a user equipment (UE) , may include receiving, by a first subscriber identity module (SIM) that is attached with New Radio (NR) service to a first cell in a non-standalone (NSA) network, a tracking area update (TAU) rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for dual connectivity with NR (DCNR) . The method also includes adding, for the first SIM, a public land mobile network (PLMN) associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message. The method further includes determining, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell, and transmitting, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the UE to receive, by a first SIM that is attached with NR service to a first cell in an NSA network, a TAU rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for DCNR and add, for the first SIM, a PLMN associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message. The one or more instructions, when executed by the one or more processors of the UE, may cause the UE to determine, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell, and transmit, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.

In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive, by a first SIM that is attached with NR service to a first cell in an NSA network, a TAU rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for DCNR, and add, for the first SIM, a PLMN associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message. The memory and the one or more processors may be configured to determine, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell, and transmit, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.

In some aspects, an apparatus for wireless communication may include means for receiving, by a first SIM that is attached with NR service to a first cell in an NSA network, a TAU rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for DCNR, and means for adding, for the first SIM, a PLMN associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message. The apparatus may include means for determining, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell, and means for transmitting, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the drawings and specification.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements.

Fig. 1 is a block diagram conceptually illustrating an example of a wireless communication network, in accordance with various aspects of the present disclosure.

Fig. 2 is a block diagram conceptually illustrating an example of a base station in communication with a user equipment (UE) in a wireless communication network, in accordance with various aspects of the present disclosure.

Fig. 3 is a diagram illustrating an example of disabling New Radio data service for dual subscriber identity modules with an attach request, in accordance with various aspects of the present disclosure.

Fig. 4 is a diagram illustrating an example process performed, for example, by a UE, in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein one skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, and/or the like (collectively referred to as “elements” ) . These elements may be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

It should be noted that while aspects may be described herein using terminology commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as 5G and later, including NR technologies.

Fig. 1 is a diagram illustrating a wireless network 100 in which aspects of the present disclosure may be practiced. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. The wireless network 100 may include a number of BSs 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A BS is an entity that communicates with user equipment (UEs) and may also be referred to as a base station, an NR BS, a Node B, a gNB, a 5G node B (NB) , an access point, a transmit receive point (TRP) , and/or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG) ) . A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in Fig. 1, a BS 110a may be a macro BS for a macro cell 102a, a BS 110b may be a pico BS for a pico cell 102b, and a BS 110c may be a femto BS for a femto cell 102c. A BS may support one or multiple (e.g., three) cells. The terms “eNB” , “base station” , “NR BS” , “gNB” , “TRP” , “AP” , “node B” , “5G NB” , and “cell” may be used interchangeably herein.

In some aspects, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, and/or the like using any suitable transport network.

Wireless network 100 may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS) . A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in Fig. 1, a relay station 110d may communicate with macro BS 110a and a UE 120d in order to facilitate communication between BS 110a and UE 120d. A relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 watts) .

A network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs. Network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with one another, e.g., directly or indirectly via a wireless or wireline backhaul.

UEs 120 (e.g., 120a, 120b, 120c) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, and/or the like. A UE may be a cellular phone (e.g., a smart phone) , a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet) ) , an entertainment device (e.g., a music or video device, or a satellite radio) , a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, and/or the like, that may communicate with a base station, another device (e.g., remote device) , or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, and/or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE) . UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like. In some aspects, the processor components and the memory components may be coupled together. For example, the processor components (e.g., one or more processors) and the memory components (e.g., a memory) may be operatively coupled, communicatively coupled, electronically coupled, electrically coupled, and/or the like.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular radio access technology (RAT) and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, and/or the like. A frequency may also be referred to as a carrier, a frequency channel, and/or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another) . For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, and/or the like) , a mesh network, and/or the like. In this case, the UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station 110.

As indicated above, Fig. 1 is provided as an example. Other examples may differ from what is described with regard to Fig. 1.

Fig. 2 shows a block diagram of a design 200 of base station 110 and UE 120, which may be one of the base stations and one of the UEs in Fig. 1. Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general T ≥ 1 and R ≥ 1.

At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS (s) selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., the cell-specific reference signal (CRS) ) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS) ) . A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232a through 232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM and/or the like) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232a through 232t may be transmitted via T antennas 234a through 234t, respectively. According to various aspects described in more detail below, the synchronization signals can be generated with location encoding to convey additional information.

At UE 120, antennas 252a through 252r may receive the downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280. A channel processor may determine reference signal received power (RSRP) , received signal strength indicator (RSSI) , reference signal received quality (RSRQ) , channel quality indicator (CQI) , and/or the like. In some aspects, one or more components of UE 120 may be included in a housing.

Network controller 130 may include communication unit 294, controller/processor 290, and memory 292. Network controller 130 may include, for example, one or more devices in a core network. Network controller 130 may communicate with base station 110 via communication unit 294.

On the uplink, at UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports that include RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like) , and transmitted to base station 110. In some aspects, the UE 120 includes a transceiver. The transceiver may include any combination of antenna (s) 252, modulators and/or demodulators 254, MIMO detector 256, receive processor 258, transmit processor 264, and/or TX MIMO processor 266. The transceiver may be used by a processor (e.g., controller/processor 280) and memory 282 to perform aspects of any of the methods described herein, for example, as described with reference to Figs. 3-4.

At base station 110, the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to controller/processor 240. Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244. Base station 110 may include a scheduler 246 to schedule UEs 120 for downlink and/or uplink communications. In some aspects, the base station 110 includes a transceiver. The transceiver may include any combination of antenna (s) 234, modulators and/or demodulators 232, MIMO detector 236, receive processor 238, transmit processor 220, and/or TX MIMO processor 230. The transceiver may be used by a processor (e.g., controller/processor 240) and memory 242 to perform aspects of any of the methods described herein, for example, as described with reference to Figs. 3-4.

Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform one or more techniques associated with disabling NR data service for dual subscriber identity modules (SIMs) with an attach request, as described in more detail elsewhere herein. For example, controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform or direct operations of, for example, process 500 of Fig. 5, and/or other processes as described herein.

Memories

242 and 282 may store data and program codes for base station 110 and UE 120, respectively. In some aspects, memory 242 and/or memory 282 may comprise a non-transitory computer-readable medium storing one or more instructions for wireless communication. For example, the one or more instructions, when executed (e.g., directly, or after compiling, converting, interpreting, and/or the like) by one or more processors of the base station 110 and/or the UE 120, may perform or direct operations of, for example, process 500 of Fig. 5, and/or other processes as described herein. In some aspects, executing instructions may include running the instructions, converting the instructions, compiling the instructions, interpreting the instructions, and/or the like. A scheduler 246 may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, UE 120 may include means for receiving, by a first SIM that is attached with NR service to a first cell in a non-standalone (NSA) network, a tracking area update (TAU) rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for dual connectivity with NR (DCNR) , means for adding, for the first SIM, a public land mobile network (PLMN) associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message, means for determining, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell, means for transmitting, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list, and/or the like. In some aspects, such means may include one or more components of UE 120 described in connection with Fig. 2, such as controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, and/or the like.

As indicated above, Fig. 2 is provided as an example. Other examples may differ from what is described with regard to Fig. 2.

A PLMN is a combination of wireless communication services (e.g., voice calls, emergency calls, messaging services, data services, and/or the like) offered by an operator. The PLMN may include several RATs, including LTE and 5G. The several RATs may provide services to UEs from multiple cells.

In some aspects, a UE may have an issue with a data service using a cell in a PLMN. For example, an NR data service for a UE attached to a first cell in an NSA network may be problematic or unstable. The UE may attempt to stabilize data service for the UE by attempting to fall back to LTE or a more stable data service. For example, the UE may transmit a TAU request to the network, indicating no support for DCNR. However, the UE may receive a TAU rejection message from the network. The message may include a cause value of 9, which may mean that the network is not able to derive an identity for the UE. In some aspects, the UE may address this with a solution that includes adding a PLMN associated with the first cell to a list of PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred. The list of PLMNs may be used because the TAU rejection message, if received for one cell of the PLMN, may be received for other cells associated with the PLMN. The UE may refrain from transmitting TAU requests indicating no DCNR support to cells associated with PLMNs in the list of PLMNs. Instead of transmitting a TAU request indicating no DCNR support, the UE may transmit an attach request indicating no DCNR support. In this way, the UE may successfully fall back to another data service.

The solution with the list of PLMNs may work for the UE if the UE has a single SIM. However, the UE may have a dual SIM modem. If a first SIM of the UE experiences difficulty with TAU requests, a second SIM of the UE that is attached to a second cell with NR data service may also experience such difficulty. For example, if the second SIM determines to disable the NR data service, the second SIM may transmit a TAU request indicating no DCNR support. The second SIM may receive a TAU rejection message, unaware that the second cell is associated with the same PLMN as the first cell, or with another PLMN that has issues with TAU rejection messages. The second SIM may cause the UE to waste time, power, processing resources, and signaling resources transmitting TAU requests and receiving TAU rejection messages.

According to various aspects described herein, the UE, for the first SIM, may add a PLMN associated with an issue cell to the list of PLMNs and synchronize this list with a list of PLMNs maintained for the second SIM. In this way, if it is determined that the second SIM is to disable an NR data service, the second SIM (or the UE for the second SIM) may determine whether a second cell to which the second SIM is attached is associated with a PLMN in the list. If not, the second SIM (or the UE for the second SIM) may transmit a TAU request indicating no DCNR support. If the second cell is associated with a PLMN in the list of PLMNs, the second SIM may proceed with transmitting an attach request indicating no DCNR support rather than a TAU request indicating no DCNR support. As a result, the second SIM causes the UE to save time, power, processing resources, and signaling resources by avoiding repeated TAU rejection messages. The second SIM may also obtain a data service quicker, providing the user a better experience.

Fig. 3 is a diagram illustrating an example 300 of disabling NR data service for dual SIMs with an attach request, in accordance with various aspects of the present disclosure. Fig. 3 shows a signaling diagram for a first SIM and a second SIM of a UE (e.g., UE 120 and or the like) configured with a dual modem. Either SIM may support dual SIM dual active or dual SIM dual standby, and either SIM may be associated with a default data subscriber (DDS) subscriber registration (e.g., NSA) or a non-DDS subscriber registration (e.g., LTE) . For example, the first SIM may register with an NSA network. The NSA network may involve the infrastructure of an LTE network that provides access to the Internet. The second SIM may also register with the NSA network or an LTE network. While actions may be described herein as being performed by the first SIM or the second SIM, this includes the UE performing the action for the first SIM or for the second SIM. In some cases, an application protocol/application processor of the UE may direct switching between the first SIM and the second SIM or other operations.

As shown by reference number 305, the UE may transmit an attach request to a first cell (Cell 1) , indicating support for DCNR. As shown by reference number 310, the UE may receive an attach accept message. The UE may enjoy an NR data service with Cell 1. However, if there is an issue with the NR data service on Cell 1, the UE may attempt to disable the NR data service, as shown by reference number 315, so as to fall back to another data service that may be more stable.

As shown by reference number 320, the first SIM (or the UE for the first SIM) may determine whether Cell 1 is associated with a PLMN in a list of one or more PLMNs associated with cells to which TAU requests indicating no DCNR support are barred. If the PLMN associated with Cell 1 is in the list of PLMNs, the first SIM may transmit an attach request indicating no DCNR support rather than a TAU request, as shown by reference number 360. The first SIM may receive an attach accept message as shown by reference number 365.

In some aspects, if the PLMN associated with Cell 1 is not in the list of PLMNs, the first SIM may transmit a TAU request indicating no DCNR support, as shown by reference number 325. However, if the first SIM receives a TAU rejection message, such as including a cause value of 9 as shown by reference number 330, the first SIM may add a PLMN associated with Cell 1 to the list of PLMNs (e.g., attach_replace_tau_list) , as shown by reference number 335. In some aspects, the first SIM may signal, to the second SIM, information about the PLMN being added to the list of PLMNs, as shown by reference number 340. The first SIM and the second SIM may synchronize respective lists of PLMNs that each SIM maintains. Alternatively, or additionally, the first SIM and the second SIM may access the same list of PLMNs.

As shown in Fig. 3, the UE may switch from the first SIM to the second SIM. The second SIM may be attached with NR data service to a second cell (Cell 2) . For example, the second SIM (or the UE for the second SIM) may transmit an attach request indicating DCNR support to Cell 2, as shown by reference number 345. The second SIM may receive an attach accept message, as shown by reference number 350. Cell 2 may share the same operator (PLMN) as Cell 1. If the UE determines, for the second SIM, to disable an NR data service, as shown by reference number 355, the UE may determine, for the second SIM, whether a PLMN associated with Cell 2 is in a list of PLMNs associated with cells to which TAU requests indicting no DCNR support are barred. If Cell 2 is associated with a PLMN in the list of PLMNs, the second SIM (or the UE for the second SIM) may transmit an attach request indicating no DCNR support to Cell 2, as shown by reference number 370, rather than a TAU request indicating no DCNR support. As shown by reference number 375, the second SIM may receive an attach accept message. The second SIM may still obtain a data service, through falling back to LTE or another data service, rather than suffer an unstable data service due to TAU rejection messages.

In some aspects, the UE may remove, for the first SIM and/or the second SIM, a cell from a list of PLMNs based at least in part on expiration of a timer, an instruction from the base station, or removal of the first SIM and/or the second SIM.

As indicated above, Fig. 3 is provided as an example. Other examples may differ from what is described with respect to Fig. 3.

Fig. 4 is a diagram illustrating an example process 400 performed, for example, by a UE, in accordance with various aspects of the present disclosure. Example process 400 is an example where the UE (e.g., UE 120 and/or the like) performs operations associated with disabling NR data service for dual SIMs with an attach request.

As shown in Fig. 4, in some aspects, process 400 may include receiving, by a first SIM that is attached with NR service to a first cell in an NSA network, a TAU rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for DCNR (block 410) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may receive, by a first SIM that is attached with NR service to a first cell in an NSA network, a TAU rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for DCNR, as described above.

As further shown in Fig. 4, in some aspects, process 400 may include adding, for the first SIM, a PLMN associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message (block 420) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may add, for the first SIM, a PLMN associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message, as described above.

As further shown in Fig. 4, in some aspects, process 400 may include determining, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell (block 430) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may determine, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell, as described above.

As further shown in Fig. 4, in some aspects, process 400 may include transmitting, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list (block 440) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may transmit, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list, as described above.

Process 400 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, process 400 includes causing the first SIM to signal information for the list to the second SIM.

In a second aspect, alone or in combination with the first aspect, the rejection message from the first cell indicates a cause value of 9.

In a third aspect, alone or in combination with one or more of the first and second aspects, the rejection message from the first cell indicates that an identity of the UE cannot be derived by the first cell.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, process 400 includes transmitting, for the first SIM, an attach request to the second cell indicating no DCNR support.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, process 400 includes removing the PLMN from the list based at least in part on receiving an instruction to remove the PLMN from the list.

Although Fig. 4 shows example blocks of process 400, in some aspects, process 400 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 4. Additionally, or alternatively, two or more of the blocks of process 400 may be performed in parallel.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construed as hardware, software, and/or a combination of hardware and software. As used herein, a processor is implemented in hardware, software, and/or a combination of hardware and software. Software is to be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and/or the like, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

As used herein, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.

It will be apparent that systems and/or methods described herein may be implemented in different forms of hardware, software, and/or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code-it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description herein.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like) , and may be used interchangeably with “one or more. ” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” and/or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.

Claims

A method of wireless communication performed by a user equipment (UE) , comprising:

receiving, by a first subscriber identity module (SIM) that is attached with New Radio (NR) service to a first cell in a non-standalone network, a tracking area update (TAU) rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for dual connectivity with NR (DCNR) ;

adding, for the first SIM, a public land mobile network (PLMN) associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message;

determining, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell; and

transmitting, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.
The method of claim 1, further comprising causing the first SIM to signal information for the list to the second SIM.
The method of claim 1, wherein the rejection message from the first cell indicates a cause value of 9.
The method of claim 1, wherein the rejection message from the first cell indicates that an identity of the UE cannot be derived by the first cell.
The method of claim 1, further comprising transmitting, for the first SIM, an attach request to the second cell indicating no DCNR support.
The method of claim 1, further comprising removing the PLMN from the list based at least in part on receiving an instruction to remove the PLMN from the list.
A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising:

one or more instructions that, when executed by one or more processors of a user equipment (UE) , cause the UE to:

receive, by a first subscriber identity module (SIM) that is attached with New Radio (NR) service to a first cell in a non-standalone network, a tracking area update (TAU) rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for dual connectivity with NR (DCNR) ;

add, for the first SIM, a public land mobile network (PLMN) associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message;

determine, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell; and

transmit, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.
A user equipment (UE) for wireless communication, comprising:

a memory; and

one or more processors operatively coupled to the memory, the memory and the one or more processors configured to:

receive, by a first subscriber identity module (SIM) that is attached with New Radio (NR) service to a first cell in a non-standalone network, a tracking area update (TAU) rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for dual connectivity with NR (DCNR) ;

add, for the first SIM, a public land mobile network (PLMN) associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message;

determine, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell; and

transmit, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.
An apparatus for wireless communication, comprising:

means for receiving, by a first subscriber identity module (SIM) that is attached with New Radio (NR) service to a first cell in a non-standalone network, a tracking area update (TAU) rejection message from the first cell based at least in part on transmitting, for the first SIM, a TAU request that indicates no support for dual connectivity with NR (DCNR) ;

means for adding, for the first SIM, a public land mobile network (PLMN) associated with the first cell to a list of one or more PLMNs that are associated with cells to which TAU requests indicating no DCNR support are barred, based at least in part on receiving the TAU rejection message;

means for determining, for a second SIM that is attached with NR service to a second cell, that the second cell is associated with a PLMN on the list, based at least in part on a determination to disable NR service with the second cell; and

means for transmitting, for the second SIM, an attach request to the second cell indicating no support for DCNR, based at least in part on the determining that the second cell is associated with a PLMN on the list.