WO2022099591A1

WO2022099591A1 - Smart internet pdn/pdu connection for msim device

Info

Publication number: WO2022099591A1
Application number: PCT/CN2020/128596
Authority: WO
Inventors: Yan Zhang; Ling Xie; Liping Shen; Can ZHAO; Beijing TIAN; Feng Chen; Qingxin Chen; Reza Shahidi; Mutaz Zuhier Afif SHUKAIR
Original assignee: Qualcomm Incorporated
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2022-05-19

Abstract

Aspects are provided which allow a multi-SIM UE to experience improved performance following a dedicated data subscription (DDS) switch, by preventing data interruptions in the network associated with a DDS SIM of the UE due to frequent paging requests in the network associated with a non-DDS SIM of the UE. The UE supports a first connection associated with a first subscription and a second connection associated with a second subscription, where the first subscription comprises a DDS. The UE switches the DDS from the first subscription to the second subscription, and disconnects the first connection following the switching. In an additional aspect, the UE reconnects the first connection after the disconnecting. As a result, the UE may no longer receive paging from the network associated with the first subscription (the new, non-DDS SIM), thereby preventing data interruptions in the network associated with the new DDS SIM and improving performance.

Description

SMART INTERNET PDN/PDU CONNECTION FOR MSIM DEVICE

BACKGROUND

Technical Field

The present disclosure generally relates to communication systems, and more particularly, to a wireless communication system between a user equipment (UE) and a base station.

Introduction

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. 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, and time division synchronous code division multiple access (TD-SCDMA) systems.

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example telecommunication standard is 5G New Radio (NR) . 5G NR is part of a continuous mobile broadband evolution promulgated by Third Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with Internet of Things (IoT) ) , and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB) , massive machine type communications (mMTC) , and ultra-reliable low latency communications (URLLC) . Some aspects of 5G NR may be based on the 4G Long Term Evolution (LTE) standard. There exists a need for further improvements in 5G NR technology. These improvements may also be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.

SUMMARY

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a UE. The apparatus supports a first connection associated with a first subscription and a second connection associated with a second subscription, where the first subscription comprises a dedicated data subscription. The apparatus switches the dedicated data subscription from the first subscription to the second subscription. The apparatus disconnects the first connection following the switching.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network.

FIG. 2A is a diagram illustrating an example of a first frame, in accordance with various aspects of the present disclosure.

FIG. 2B is a diagram illustrating an example of DL channels within a subframe, in accordance with various aspects of the present disclosure.

FIG. 2C is a diagram illustrating an example of a second frame, in accordance with various aspects of the present disclosure.

FIG. 2D is a diagram illustrating an example of UL channels within a subframe, in accordance with various aspects of the present disclosure.

FIG. 3 is a diagram illustrating an example of a base station and user equipment (UE) in an access network.

FIG. 4 is a diagram illustrating an example of a UE in communication with base stations over data connections associated with different subscriptions.

FIG. 5 is a diagram illustrating an example of a call flow between a UE and a base station.

FIG. 6 is a flowchart of a method of wireless communication.

FIG. 7 is a diagram illustrating an example of a hardware implementation for an example apparatus.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

To communicate with a base station in a wireless network, a UE may first form a connection with the network. The forming of the connection may depend on the radio access technology (RAT) associated with the network. For example, in an LTE network, the UE may perform a PDN connectivity procedure requesting the setup of an Evolved Packet System (EPS) bearer to a PDN. Similarly, in a 5G/NR network, the UE may perform a PDU session establishment procedure to establish a new PDU session with a destination network (DN) . The network may also assign an IP address to the UE during the PDN connectivity request or PDU session establishment procedures.

The UE may also release the connection formed with the base station within the network. The releasing of the connection may similarly depend on the RAT associated with the network. For example, in an LTE network, the UE may perform a PDN disconnect procedure requesting disconnection from a PDN. Similarly, in a 5G/NR network, the UE may perform a PDU session release procedure to request a release of a PDU session.

Typically, the network with which the UE forms the aforementioned connection is associated with a subscriber identity module (SIM) (or SIM card) of the UE. However, a UE may also include more than one SIM or SIM card. Such UEs may be referred to as multi-SIM UEs (MSIM UEs) . For example, a MSIM UE may include a first SIM connected to one Public Land Mobile Network (PLMN) associated with one operator and a second SIM connected to a different PLMN associated with a different operator. In such case, MSIM UEs may form a connection with one or more base stations within the PLMN associated with each SIM. For example, in an LTE network, the MSIM UE may perform a PDN connectivity procedure for each SIM requesting the setup of an EPS bearer to a PDN. Similarly, in a 5G/NR network, a MSIM UE may perform a PDU session establishment procedure for each SIM to establish a new PDU session with a DN for the respective SIM.

Moreover, each SIM may be associated with a separate subscription to a respective mobile network. For example, a first SIM supporting a connection with one PLMN may be associated with a dedicated data subscription (DDS) , while a second SIM supporting a connection with another PLMN may be associated with a non-dedicated data subscription (non-DDS) . A DDS refers to a subscription which the UE selects to receive data from a network (e.g. internet data such as video and gaming) , while a non-DDS refers to a subscription which the UE selects to receive voice calls or voice over LTE (VoLTE) from a network. Thus, a MSIM UE including two SIMs respectively associated with DDS and non-DDS may receive data using the first SIM (e.g. the DDS SIM) in a primary subscription (Sub1) and voice calls using the second SIM (e.g. the non-DDS SIM) in a secondary subscription (Sub2) .

MSIM UEs may switch the SIMs associated with DDS and non-DDS in response to user input. For instance, if a MSIM UE by default selects a first SIM (Sub1) to be associated with DDS and a second SIM (Sub2) to be associated with non-DDS, then in response to a user selection, the UE may change the association such that the second SIM (Sub2) is now associated with DDS and thus that the first SIM (Sub1) is associated with non-DDS. The MSIM UE may also determine to switch the DDS from the one SIM to another when the UE experiences a large delay in data reception or a decrease in link quality in the network associated with the DDS SIM. For example, when a base station in a network associated with the first SIM communicates video or game data in a DDS to the UE, performance may be visibly degraded due to signal interference, low power signals to save battery charge, or network slicing resulting in low QoS. In such case, if the network associated with the second SIM is not experiencing the same interference, low power signals, or low QoS, the MSIM UE may switch the DDS to the second SIM for better performance. As a result, the UE may receive data in Sub2 using the second SIM (the new DDS SIM) and voice calls in Sub1 using the first SIM (the new, non-DDS SIM) .

However, MSIM UEs typically do not release the connection for a SIM after switching the DDS to another SIM. For example, in an LTE network, the MSIM UE may not perform a PDN disconnect procedure in Sub1 for the new, non-DDS SIM to request disconnection from the PDN. Similarly, in a 5G/NR network, the MSIM UE may not perform a PDU session release procedure to request a release of a PDU session in Sub1 associated with the new, non-DDS SIM. As a result, the UE may maintain the PDN connection or PDU session in Sub1 with the new, non-DDS SIM, as well as the connection or session in Sub2 with the new DDS SIM. Such arrangement may result in degradation of performance in Sub2 since the UE may frequently suspend its connection in Sub2 to monitor for paging over the active connection in Sub1.

To address this impact in performance, in one aspect, the UE may trigger a release of the connection in Sub1 (for the new, non-DDS SIM) in response to the DDS switch to Sub2. For example, if Sub1 is associated with an LTE network, then after determining to switch the DDS to the new DDS SIM in Sub2, the MSIM UE may perform a PDN disconnect procedure in Sub1 requesting disconnection from the PDN. Similarly, if Sub1 is associated with a 5G/NR network, then after determining to switch the DDS to the new DDS SIM in Sub2, the MSIM UE may perform a PDU session release procedure to request a release of a PDU session in Sub1. As a result, the network associated with the new, non-DDS SIM (Sub1) may be informed of the connection release and the UE may consequently no longer receive paging from that network, thereby preventing data interruptions in the network associated with the new DDS SIM (Sub2) and improving performance.

In another aspect, the UE may trigger a re-forming of the connection in Sub1 for the new, non-DDS SIM in response to the connection release following the DDS switch. For example, if Sub1 is associated with an LTE network, the MSIM UE may perform a PDN connectivity procedure in Sub1 re-requesting the setup of an EPS bearer to a PDN. Similarly, if Sub1 is associated with a 5G/NR network, the MSIM UE may perform a PDU session establishment procedure in Sub1 to re-establish a new PDU session with the DN. As a result, the network associated with the new, non-DDS SIM (Sub1) may assign a new internet protocol (IP) address to the UE during the PDN connectivity request or PDU session establishment procedures. This new IP address may be different from the previous IP address of the UE to which periodic paging by that network was directed, thereby preventing the UE from receiving further paging from the network associated with the new, non-DDS SIM (Sub1) . As a result, data interruptions in the network associated with the new DDS SIM (Sub2) may be mitigated and improved performance may result.

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

By way of example, an element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs) , central processing units (CPUs) , application processors, digital signal processors (DSPs) , reduced instruction set computing (RISC) processors, systems on a chip (SoC) , baseband processors, field programmable gate arrays (FPGAs) , programmable logic devices (PLDs) , state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

Accordingly, in one or more example embodiments, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise a random-access memory (RAM) , a read-only memory (ROM) , an electrically erasable programmable ROM (EEPROM) , optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the aforementioned types of computer-readable media, or any other medium that can be used to store computer executable code in the form of instructions or data structures that can be accessed by a computer.

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network 100. The wireless communications system (also referred to as a wireless wide area network (WWAN) ) includes base stations 102, user equipment (s) (UE) 104, an Evolved Packet Core (EPC) 160, and another core network 190 (e.g., a 5G Core (5GC) ) . The base stations 102 may include macrocells (high power cellular base station) and/or small cells (low power cellular base station) . The macrocells include base stations. The small cells include femtocells, picocells, and microcells.

The base stations 102 configured for 4G Long Term Evolution (LTE) (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN) ) may interface with the EPC 160 through first backhaul links 132 (e.g., S1 interface) . The base stations 102 configured for 5G New Radio (NR) (collectively referred to as Next Generation RAN (NG-RAN) ) may interface with core network 190 through second backhaul links 184. In addition to other functions, the base stations 102 may perform one or more of the following functions: transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity) , inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, Multimedia Broadcast Multicast Service (MBMS) , subscriber and equipment trace, RAN information management (RIM) , paging, positioning, and delivery of warning messages. The base stations 102 may communicate directly or indirectly (e.g., through the EPC 160 or core network 190) with each other over third backhaul links 134 (e.g., X2 interface) . The first backhaul links 132, the second backhaul links 184, and the third backhaul links 134 may be wired or wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Each of the base stations 102 may provide communication coverage for a respective geographic coverage area 110. There may be overlapping geographic coverage areas 110. For example, the small cell 102' may have a coverage area 110' that overlaps the coverage area 110 of one or more macro base stations 102. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs) , which may provide service to a restricted group known as a closed subscriber group (CSG) . The communication links 120 between the base stations 102 and the UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to a base station 102 and/or downlink (DL) (also referred to as forward link) transmissions from a base station 102 to a UE 104. The communication links 120 may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links may be through one or more carriers. The base stations 102 /UEs 104 may use spectrum up to Y megahertz (MHz) (e.g., 5, 10, 15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction. The carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL) . The component carriers may include a primary component carrier and one or more secondary component carriers. A primary component carrier may be referred to as a primary cell (PCell) and a secondary component carrier may be referred to as a secondary cell (SCell) .

Certain UEs 104 may communicate with each other using device-to-device (D2D) communication link 158. The D2D communication link 158 may use the DL/UL WWAN spectrum. The D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH) , a physical sidelink discovery channel (PSDCH) , a physical sidelink shared channel (PSSCH) , and a physical sidelink control channel (PSCCH) . D2D communication may be through a variety of wireless D2D communications systems, such as for example, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

The wireless communications system may further include a Wi-Fi access point (AP) 150 in communication with Wi-Fi stations (STAs) 152 via communication links 154, e.g., in a 5 gigahertz (GHz) unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the STAs 152 /AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

The small cell 102' may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell 102' may employ NR and use the same unlicensed frequency spectrum (e.g., 5 GHz, or the like) as used by the Wi-Fi AP 150. The small cell 102', employing NR in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network.

The electromagnetic spectrum is often subdivided, based on frequency/wavelength, into various classes, bands, channels, etc. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz –7.125 GHz) and FR2 (24.25 GHz –52.6 GHz) . The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to (interchangeably) as a “sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often referred to (interchangeably) as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz –300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.

With the above aspects in mind, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like if used herein may broadly represent frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Further, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like if used herein may broadly represent frequencies that may include mid-band frequencies, may be within FR2, or may be within the EHF band.

A base station 102, whether a small cell 102' or a large cell (e.g., macro base station) , may include and/or be referred to as an eNB, gNodeB (gNB) , or another type of base station. Some base stations, such as gNB 180 may operate in a traditional sub 6 GHz spectrum, in millimeter wave frequencies, and/or near millimeter wave frequencies in communication with the UE 104. When the gNB 180 operates in millimeter wave or near millimeter wave frequencies, the gNB 180 may be referred to as a millimeter wave base station. The millimeter wave base station 180 may utilize beamforming 182 with the UE 104 to compensate for the path loss and short range. The base station 180 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate the beamforming.

The base station 180 may transmit a beamformed signal to the UE 104 in one or more transmit directions 182'. The UE 104 may receive the beamformed signal from the base station 180 in one or more receive directions 182”. The UE 104 may also transmit a beamformed signal to the base station 180 in one or more transmit directions. The base station 180 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 180 /UE 104 may perform beam training to determine the best receive and transmit directions for each of the base station 180 /UE 104. The transmit and receive directions for the base station 180 may or may not be the same. The transmit and receive directions for the UE 104 may or may not be the same.

The EPC 160 may include a Mobility Management Entity (MME) 162, other MMEs 164, a Serving Gateway 166, an MBMS Gateway 168, a Broadcast Multicast Service Center (BM-SC) 170, and a Packet Data Network (PDN) Gateway 172. The MME 162 may be in communication with a Home Subscriber Server (HSS) 174. The MME 162 is the control node that processes the signaling between the UEs 104 and the EPC 160. Generally, the MME 162 provides bearer and connection management. All user Internet protocol (IP) packets are transferred through the Serving Gateway 166, which itself is connected to the PDN Gateway 172. The PDN Gateway 172 provides UE IP address allocation as well as other functions. The PDN Gateway 172 and the BM-SC 170 are connected to the IP Services 176. The IP Services 176 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a PS Streaming Service, and/or other IP services. The BM-SC 170 may provide functions for MBMS user service provisioning and delivery. The BM-SC 170 may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a public land mobile network (PLMN) , and may be used to schedule MBMS transmissions. The MBMS Gateway 168 may be used to distribute MBMS traffic to the base stations 102 belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service, and may be responsible for session management (start/stop) and for collecting eMBMS related charging information.

The core network 190 may include a Access and Mobility Management Function (AMF) 192, other AMFs 193, a Session Management Function (SMF) 194, and a User Plane Function (UPF) 195. The AMF 192 may be in communication with a Unified Data Management (UDM) 196. The AMF 192 is the control node that processes the signaling between the UEs 104 and the core network 190. Generally, the AMF 192 provides Quality of Service (QoS) flow and session management. All user IP packets are transferred through the UPF 195. The UPF 195 provides UE IP address allocation as well as other functions. The UPF 195 is connected to the IP Services 197. The IP Services 197 may include the Internet, an intranet, an IMS, a Packet Switch (PS) Streaming Service, and/or other IP services.

The base station may include and/or be referred to as a gNB, Node B, eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS) , an extended service set (ESS) , a transmit reception point (TRP) , or some other suitable terminology. The base station 102 provides an access point to the EPC 160 or core network 190 for a UE 104. Examples of UEs 104 include a cellular phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal digital assistant (PDA) , a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player (e.g., MP3 player) , a camera, a game console, a tablet, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor/actuator, a display, or any other similar functioning device. Some of the UEs 104 may be referred to as IoT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc. ) . The UE 104 may also be referred to as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology.

Although the present disclosure may focus on 5G NR, the concepts and various aspects described herein may be applicable to other similar areas, such as LTE, LTE-Advanced (LTE-A) , Code Division Multiple Access (CDMA) , Global System for Mobile communications (GSM) , or other wireless/radio access technologies.

Referring again to FIG. 1, in certain aspects, the UE 104 may include a DDS component 198 that is configured to support a first connection associated with a first subscription and a second connection associated with a second subscription, where the first subscription comprises a dedicated data subscription. The DDS component 198 is also configured to switch the dedicated data subscription from the first subscription to the second subscription, and to disconnect the first connection following the switching.

FIG. 2A is a diagram 200 illustrating an example of a first subframe within a 5G NR frame structure. FIG. 2B is a diagram 230 illustrating an example of DL channels within a 5G NR subframe. FIG. 2C is a diagram 250 illustrating an example of a second subframe within a 5G NR frame structure. FIG. 2D is a diagram 280 illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplexed (FDD) in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for either DL or UL, or may be time division duplexed (TDD) in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for both DL and UL. In the examples provided by FIGs. 2A, 2C, the 5G NR frame structure is assumed to be TDD, with subframe 4 being configured with slot format 28 (with mostly DL) , where D is DL, U is UL, and F is flexible for use between DL/UL, and subframe 3 being configured with slot format 34 (with mostly UL) . While

subframes

3, 4 are shown with slot formats 34, 28, respectively, any particular subframe may be configured with any of the various available slot formats 0-61. Slot formats 0, 1 are all DL, UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. UEs are configured with the slot format (dynamically through DL control information (DCI) , or semi-statically/statically through radio resource control (RRC) signaling) through a received slot format indicator (SFI) . Note that the description infra applies also to a 5G NR frame structure that is TDD.

Other wireless communication technologies may have a different frame structure and/or different channels. A frame, e.g., of 10 milliseconds (ms) , may be divided into 10 equally sized subframes (1 ms) . Each subframe may include one or more time slots. Subframes may also include mini-slots, which may include 7, 4, or 2 symbols. Each slot may include 7 or 14 symbols, depending on the slot configuration. For slot configuration 0, each slot may include 14 symbols, and for slot configuration 1, each slot may include 7 symbols. The symbols on DL may be cyclic prefix (CP) orthogonal frequency-division multiplexing (OFDM) (CP-OFDM) symbols. The symbols on UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also referred to as single carrier frequency-division multiple access (SC-FDMA) symbols) (for power limited scenarios; limited to a single stream transmission) . The number of slots within a subframe is based on the slot configuration and the numerology. For slot configuration 0, different numerologies μ 0 to 4 allow for 1, 2, 4, 8, and 16 slots, respectively, per subframe. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots, respectively, per subframe. Accordingly, for slot configuration 0 and numerology μ, there are 14 symbols/slot and 2 ^μ slots/subframe. The subcarrier spacing and symbol length/duration are a function of the numerology. The subcarrier spacing may be equal to 2 ^μ*15 kilohertz (kHz) , where μ is the numerology 0 to 4. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=4 has a subcarrier spacing of 240 kHz. The symbol length/duration is inversely related to the subcarrier spacing. FIGs. 2A-2D provide an example of slot configuration 0 with 14 symbols per slot and numerology μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs. Within a set of frames, there may be one or more different bandwidth parts (BWPs) (see FIG. 2B) that are frequency division multiplexed. Each BWP may have a particular numerology.

A resource grid may be used to represent the frame structure. Each time slot includes a resource block (RB) (also referred to as physical RBs (PRBs) ) that extends 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs) . The number of bits carried by each RE depends on the modulation scheme.

As illustrated in FIG. 2A, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include demodulation RS (DM-RS) (indicated as R _x for one particular configuration, where 100x is the port number, but other DM-RS configurations are possible) and channel state information reference signals (CSI-RS) for channel estimation at the UE. The RS may also include beam measurement RS (BRS) , beam refinement RS (BRRS) , and phase tracking RS (PT-RS) .

FIG. 2B illustrates an example of various DL channels within a subframe of a frame. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) , each CCE including nine RE groups (REGs) , each REG including four consecutive REs in an OFDM symbol. A PDCCH within one BWP may be referred to as a control resource set (CORESET) . Additional BWPs may be located at greater and/or lower frequencies across the channel bandwidth. A primary synchronization signal (PSS) may be within symbol 2 of particular subframes of a frame. The PSS is used by a UE 104 to determine subframe/symbol timing and a physical layer identity. A secondary synchronization signal (SSS) may be within symbol 4 of particular subframes of a frame. The SSS is used by a UE to determine a physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine a physical cell identifier (PCI) . Based on the PCI, the UE can determine the locations of the aforementioned DM-RS. The physical broadcast channel (PBCH) , which carries a master information block (MIB) , may be logically grouped with the PSS and SSS to form a synchronization signal (SS) /PBCH block (also referred to as SS block (SSB) ) . The MIB provides a number of RBs in the system bandwidth and a system frame number (SFN) . The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs) , and paging messages.

As illustrated in FIG. 2C, some of the REs carry DM-RS (indicated as R for one particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may transmit DM-RS for the physical uplink control channel (PUCCH) and DM-RS for the physical uplink shared channel (PUSCH) . The PUSCH DM-RS may be transmitted in the first one or two symbols of the PUSCH. The PUCCH DM-RS may be transmitted in different configurations depending on whether short or long PUCCHs are transmitted and depending on the particular PUCCH format used. The UE may transmit sounding reference signals (SRS) . The SRS may be transmitted in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

FIG. 2D illustrates an example of various UL channels within a subframe of a frame. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI) , such as scheduling requests, a channel quality indicator (CQI) , a precoding matrix indicator (PMI) , a rank indicator (RI) , and hybrid automatic repeat request (HARQ) acknowledgement (ACK) /non-acknowledgement (NACK) feedback. The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR) , a power headroom report (PHR) , and/or UCI.

FIG. 3 is a block diagram of a base station 310 in communication with a UE 350 in an access network. In the DL, IP packets from the EPC 160 may be provided to a controller/processor 375. The controller/processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller/processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIBs) , RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release) , inter radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression /decompression, security (ciphering, deciphering, integrity protection, integrity verification) , and handover support functions; RLC layer functionality associated with the transfer of upper layer protocol data units (PDUs) , error correction through ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs) , re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs) , demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

The transmit (TX) processor 316 and the receive (RX) processor 370 implement layer 1 functionality associated with various signal processing functions. Layer 1, which includes a physical (PHY) layer, may include error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, interleaving, rate matching, mapping onto physical channels, modulation/demodulation of physical channels, and MIMO antenna processing. The TX processor 316 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK) , quadrature phase-shift keying (QPSK) , M-phase-shift keying (M-PSK) , M-quadrature amplitude modulation (M-QAM) ) . The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially precoded to produce multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE 350. Each spatial stream may then be provided to a different antenna 320 via a separate transmitter 318TX. Each transmitter 318TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 350, each receiver 354RX receives a signal through its respective antenna 352. Each receiver 354RX recovers information modulated onto an RF carrier and provides the information to the receive (RX) processor 356. The TX processor 368 and the RX processor 356 implement layer 1 functionality associated with various signal processing functions. The RX processor 356 may perform spatial processing on the information to recover any spatial streams destined for the UE 350. If multiple spatial streams are destined for the UE 350, they may be combined by the RX processor 356 into a single OFDM symbol stream. The RX processor 356 then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT) . The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station 310. These soft decisions may be based on channel estimates computed by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station 310 on the physical channel. The data and control signals are then provided to the controller/processor 359, which implements layer 3 and layer 2 functionality.

The controller/processor 359 can be associated with a memory 360 that stores program codes and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller/processor 359 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the EPC 160. The controller/processor 359 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

Similar to the functionality described in connection with the DL transmission by the base station 310, the controller/processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression /decompression, and security (ciphering, deciphering, integrity protection, integrity verification) ; RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

Channel estimates derived by a channel estimator 358 from a reference signal or feedback transmitted by the base station 310 may be used by the TX processor 368 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antenna 352 via separate transmitters 354TX. Each transmitter 354TX may modulate an RF carrier with a respective spatial stream for transmission.

The UL transmission is processed at the base station 310 in a manner similar to that described in connection with the receiver function at the UE 350. Each receiver 318RX receives a signal through its respective antenna 320. Each receiver 318RX recovers information modulated onto an RF carrier and provides the information to a RX processor 370.

The controller/processor 375 can be associated with a memory 376 that stores program codes and data. The memory 376 may be referred to as a computer-readable medium. In the UL, the controller/processor 375 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE 350. IP packets from the controller/processor 375 may be provided to the EPC 160. The controller/processor 375 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

At least one of the TX processor 368, the RX processor 356, and the controller/processor 359 may be configured to perform aspects in connection with DDS component 198 of FIG. 1.

To communicate with a base station in a wireless network, a UE may first form a connection with the network. The forming of the connection may depend on the RAT associated with the network. For example, in an LTE network, the UE may perform a PDN connectivity procedure requesting the setup of an EPS bearer to a PDN. In this procedure, the UE may request connectivity to a PDN by sending a PDN connectivity request message to the MME. If accepted by the network, this procedure initiates the establishment of an EPS bearer context. Similarly, in a 5G/NR network, the UE may perform a PDU session establishment procedure to establish a new PDU session with a DN. In this procedure, the UE may request to establish a new PDU session by sending a PDU session establishment request message to the SMF. If accepted by the network, the PDU session enables exchange of PDUs between the UE and the DN. The network may also assign an IP address to the UE during the PDN connectivity request or PDU session establishment procedures.

The UE may also release the connection formed with the base station within the network. The releasing of the connection may similarly depend on the RAT associated with the network. For example, in an LTE network, the UE may perform a PDN disconnect procedure requesting disconnection from a PDN. In this procedure, the UE may send a PDN disconnect request message to the MME including the identity of the EPS bearer associated with the PDN to be disconnected. If accepted by the network, the MME may initiate a bearer context deactivation procedure by sending a deactivate EPS bearer context request message to the UE. When the UE responds by sending a deactivate EPS bearer context accept message, the MME may release all the resources reserved for the PDN in the network. Similarly, in a 5G/NR network, the UE may perform a PDU session release procedure to request a release of a PDU session. In this procedure, the UE may send a PDU session release request message to the SMF including the PDU session ID to be released. If accepted by the network, the SMF may send a PDU session release command message to the UE. Afterwards, the UE considers the PDU session as released and responds by sending a PDU session release complete message to the network.

Typically, the network with which the UE forms the aforementioned connection is associated with a SIM (or SIM card) of the UE. However, a UE may also include more than one SIM or SIM card. Such UEs may be referred to as MSIM UEs. For example, a MSIM UE may include a first SIM connected to one PLMN associated with one operator and a second SIM connected to a different PLMN associated with a different operator. In such case, MSIM UEs may form a connection with one or more base stations within the PLMN associated with each SIM. For example, in LTE networks, the MSIM UE may perform a PDN connectivity procedure for each SIM requesting the setup of an EPS bearer to a PDN. For instance, a MSIM UE may establish a first bearer associated with a first SIM and a second bearer associated with a second SIM by including respective PDN connectivity request messages into initial attach messages to the MME (e.g. during a UE registration procedure in LTE) . Similarly, in 5G/NR networks, a MSIM UE may perform a PDU session establishment procedure for each SIM to establish a new PDU session with a DN for the respective SIM. For instance, the UE may establish a first PDU session associated with a first SIM and a second PDU session associated with a second SIM by sending respective PDU session establishment request messages to the SMF (e.g. during a UE registration procedure in 5G) .

Moreover, each SIM may be associated with a separate subscription to a respective mobile network. For example, a first SIM supporting a connection with one PLMN may be associated with a DDS, while a second SIM supporting a connection with another PLMN may be associated with a non-DDS. A DDS refers to a subscription which the UE selects to receive data from a network (e.g. internet data such as video and gaming) , while a non-DDS refers to a subscription which the UE selects to receive voice calls or voice over LTE (VoLTE) from a network. Thus, a MSIM UE including two SIMs respectively associated with DDS and non-DDS may receive data using the first SIM (e.g. the DDS SIM) in a primary subscription (Sub1) and voice calls using the second SIM (e.g. the non-DDS SIM) in a secondary subscription (Sub2) .

FIG. 4 illustrates an example 400 of a MSIM UE 402 in communication with base stations 404 in respective cells 406. In this example, the UE 402 includes a first SIM 408 associated with a first subscription 410 (Sub1) and a second SIM 412 associated with a second subscription 414 (Sub2) . For example, the first subscription 410 may be a DDS and the second subscription 414 may be a non-DDS. The UE 402 may form a connection 416 with each base station 404 in the network or cell 406 associated with the

respective SIM

408, 412. For example, depending on the RAT of each network or cell 406, the UE may connect to each base station 404 using a PDN connectivity procedure or a PDU session establishment procedure. While FIG. 4 illustrates the example where different base stations 404 are associated with the first SIM 408 and the second SIM 412, in other examples, the same base station may be associated with the first SIM 408 and the second SIM 412.

MSIM UEs may switch the SIMs associated with DDS and non-DDS in response to user input. For instance, if a MSIM UE by default selects a first SIM (Sub1) to be associated with DDS and a second SIM (Sub2) to be associated with non-DDS, then in response to a user selection, the UE may change the association such that the second SIM (Sub2) is now associated with DDS and thus that the first SIM (Sub1) is associated with non-DDS. The MSIM UE may also determine to switch the DDS from one SIM to another when the UE experiences a large delay in data reception or a decrease in link quality in the network associated with the DDS SIM. For example, when a base station in a network associated with the first SIM communicates video or game data in a DDS to the UE, performance may be visibly degraded due to signal interference, low power signals to save battery charge, or network slicing resulting in low QoS. In such case, if the network associated with the second SIM is not experiencing the same interference, low power signals, or low QoS, the MSIM UE may switch the DDS to the second SIM for better performance. As a result, the UE may receive data in Sub2 using the second SIM (the new DDS SIM) and voice calls in Sub1 using the first SIM (the new, non-DDS SIM) .

However, MSIM UEs typically do not release the connection for a SIM after switching the DDS to another SIM. For example, in an LTE network, the MSIM UE may not perform a PDN disconnect procedure in Sub1 for the new, non-DDS SIM to request disconnection from the PDN. Similarly, in a 5G/NR network, the MSIM UE may not perform a PDU session release procedure to request a release of a PDU session in Sub1 associated with the new, non-DDS SIM. As a result, the UE may maintain the PDN connection or PDU session in Sub1 with the new, non-DDS SIM as well as in Sub2 with the new DDS SIM. Such arrangement may result in degradation of performance in Sub2 as well as in Sub1.

For example, a MSIM UE typically uses common radio and baseband components that are shared among the multiple SIMs, which may prevent the UE from actively communicating using multiple SIMs at the same time. Therefore, while actively communicating with the network in Sub1 initially using a DDS SIM, a MSIM UE may occasionally monitor for paging requests from the network in Sub2 initially using a non-DDS SIM. Upon receipt of such paging requests in Sub2, the UE may respond by suspending the connection in Sub1 and establishing the connection in Sub2. However, following a DDS switch to Sub2, if the UE maintains the connection in Sub1 using the new, non-DDS SIM as described above, the suspensions and data interruptions in Sub2 may still continue. For example, since the connection in Sub1 is maintained, the UE may perform a tracking area update (TAU) to synchronize with the network associated with Sub1. As a result, the UE may frequently be paged by the network in Sub1 (e.g. in response to user datagram protocol (UDP) packets from a third-party game server, for example) , thereby in turn causing the UE to frequently suspend its connection in Sub2 to monitor for the paging. Such constant data interruptions may result in degradation of performance in Sub2 for the new DDS SIM.

To address this impact in performance, in one aspect, the UE may trigger a release of the connection in Sub1 for the new, non-DDS SIM in response to the DDS switch to Sub2. For example, in an LTE network, the MSIM UE may perform a PDN disconnect procedure in Sub1 for the new, non-DDS SIM requesting disconnection from the PDN after determining to switch the DDS to the new, DDS SIM in Sub2. Similarly, in a 5G/NR network, the MSIM UE may perform a PDU session release procedure to request a release of a PDU session in Sub1 associated with the new, non-DDS SIM after determining to switch the DDS to the new, DDS SIM in Sub2. As a result, the network associated with the new, non-DDS SIM may be informed of the connection release and the UE may consequently no longer receive paging from that network, thereby preventing data interruptions in the network associated with the new DDS SIM and improving performance.

In another aspect, the UE may trigger a re-forming of the connection in Sub1 for the new, non-DDS SIM in response to the connection release following the DDS switch. For example, in an LTE network, the MSIM UE may perform a PDN connectivity procedure in Sub1 for the new, non-DDS SIM re-requesting the setup of an EPS bearer to a PDN. Similarly, in a 5G/NR network, a MSIM UE may perform a PDU session establishment procedure in Sub1 for the new, non-DDS SIM to re-establish a new PDU session with a DN for that SIM. As a result, the network associated with the new, non-DDS SIM may assign a new IP address to the UE during the PDN connectivity request or PDU session establishment procedures. This new IP address may be different from the previous IP address of the UE to which periodic paging by the network was directed, thereby preventing the UE from receiving further paging from the network associated with the new, non-DDS SIM. As a result, data interruptions for the new DDS SIM may be mitigated and improved performance may result.

FIG. 5 is a diagram illustrating an example 500 of a call flow between a UE 502 and a base station 504. The UE 502 may correspond to MSIM UE 402 and the base station 504 may correspond to the base station 404 in the network initially associated with the DDS SIM (Sub1) . At 506, the UE 502 may initially receive data 508 from base station 504 in a first subscription (DDS) . For example, referring to FIG. 4, the UE 402 may form a connection 416 with the base station 404 in the network or cell 406 associated with the first SIM 408, and the UE may receive downlink data from the base station accordingly (e.g. video or gaming data) . Next, at 510, the UE may determine to switch the DDS to a second subscription. For example, referring to FIG. 4, the UE 402 may determine to switch the DDS from first SIM 408 to second SIM 412 in response to identifying a difference in data reception delay or link quality between the network or cell 406 associated with the first SIM 408 and the network or cell 406 associated with the second SIM 412. For example, if more signal interference, lower power signals to save battery charge, or lower QoS based on network slicing exists in the network associated with the first SIM 408 than in that of the second SIM 412, the UE may determine to switch the DDS from first subscription 410 to second subscription 414.

In response to determining to switch the DDS to the second subscription, at 512, the UE may switch the DDS to the second subscription. For example, referring to FIG. 4, the UE 402 may retune its antenna (s) to a different frequency associated with the cell 406 of the base station 404 in the network associated with the second SIM 412. In another example, the UE 402 may modify the connection 416 with the base station 404 in the network associated with the second SIM 412, e.g. by requesting modification of bearer resources associated with the second SIM 412 through a bearer resource modification request message to the MME (if in an LTE network) or by requesting to modify the PDU session through a PDU session modification request message to the SMF (if in a 5G/NR network) . In a further example, the UE may form a new connection (e.g. connection 416) with the base station 404 in the network associated with the second SIM 412 using a PDN connectivity procedure (if an LTE network) or a PDU session establishment procedure (if a 5G/NR network) . The UE may also switch the DDS to the second subscription in response to user input. After switching the DDS, at 514, the UE 502 may determine that the first subscription is a new, non-DDS. For example, referring to FIG. 4, after the second subscription 414 has been switched to DDS, the UE 402 may determine that first subscription 410 has been switched to a non-DDS, e.g., in response to identifying that video and gaming data is being received from the base station 404 in the network or cell 406 associated with the second SIM 412 rather than the first SIM 408.

Next, to prevent degradation of performance in data reception from the network associated with the second SIM 412, the UE may release the connection 416 with the base station 404 in the network associated with the first SIM 408. For example, if the first SIM 408 is associated with an LTE network, the UE may perform a PDN disconnect procedure 516 in which, for example, the UE may send a PDN disconnect request message to the MME (via base station 504) , the MME may in turn initiate a bearer context deactivation procedure by sending (also via base station 504) a deactivate EPS bearer context request message to the UE, and when the UE responds by sending a deactivate EPS bearer context accept message, the MME may release all the resources reserved for the PDN in the network associated with the first subscription 410. Alternatively, if the first SIM 408 is associated with a 5G/NR network, the UE may perform a PDU session release procedure 518 in which, for example, the UE may send a PDU session release request message to the SMF (via base station 504) , the SMF may in turn send (also via base station 504) a PDU session release command message to the UE, and the UE may respond by sending a PDU session release complete message to release the PDU session in the network associated with the first subscription 410.

Additionally, after releasing the connection, the UE 502 may create a new connection (e.g. connection 416) with the base station 404 in the network associated with the first SIM 408. For example, if the first SIM 408 is associated with an LTE network, the UE may perform a PDN connectivity procedure 520 in which, for example, the UE may send a PDN connectivity request message to the MME (via base station 504) to set up a new EPS bearer to a PDN associated with the first subscription 410. Alternatively, if the first SIM 408 is associated with a 5G/NR network, the UE may perform a PDU session establishment procedure 522 in which, for example, the UE may send a PDU session establishment request message to the SMF (via base station 504) to establish a new PDU session with the network associated with the first subscription 410.

FIG. 6 is a flowchart 600 of a method of wireless communication. The method may be performed by a UE (e.g., the

UE

104, 350, 402, 502; the apparatus 702) . Optional aspects are illustrated in dashed lines. The method allows a MSIM UE to experience improved performance following a DDS switch by preventing data interruptions in the network associated with a DDS SIM of the UE due to frequent paging requests in the network associated with a non-DDS SIM of the UE.

At 602, the UE supports a first connection associated with a first subscription and a second connection associated with a second subscription, where the first subscription comprises a dedicated data subscription. For example, 602 may be performed by support component 740. The first subscription may be for a first SIM of the UE and the second subscription may be for a second SIM of the UE. The first connection and the second connection may be to a base station or to different base stations. For instance, referring to FIG. 4, the UE 402 may form connections 416 with base stations 404 respectively associated with a first subscription 410 and a second subscription 414. The first subscription 410 may be a DDS and the second subscription 414 may be a non-DDS. The UE 402 may include a first SIM 408 associated with the first subscription 410 and a second SIM 412 associated with the second subscription 414.

At 604, the UE switches the dedicated data subscription from the first subscription to the second subscription. For example, 604 may be performed by switch component 742. For instance, referring to FIG. 5, at 512, the UE may switch the DDS to the second subscription in response to determining to switch the DDS at 510 (e.g. based on increased delay in data reception or reduction in link quality in the connection associated with the first subscription) .

At 606, the UE disconnects the first connection following the switching. For example, 606 may be performed by disconnect component 744. For instance, referring to FIG. 4, to prevent degradation of performance in data reception from the network associated with the second subscription 414 following the DDS switch, the UE may release the connection 416 with the base station 404 in the network associated with the first subscription 410. For example, at 608, the UE may perform a PDN disconnect procedure. For example, 608 may be performed by PDN disconnect component 746. For instance, referring to FIGs. 4 and 5, the

UE

402, 502 may perform PDN disconnect procedure 516 to release all the resources reserved for the PDN in the network associated with the first subscription 410. Alternatively, at 610, the UE may perform a PDU session release procedure. For example, 610 may be performed by PDU session release component 748. For instance, referring to FIGs. 4 and 5, the

UE

402, 502 may perform PDU session release procedure 518 to release the PDU session in the network associated with the first subscription 410.

Finally, at 612, the UE may reconnect the first connection after the disconnecting. For example, 612 may be performed by reconnect component 750. For instance, referring to FIGs. 4 and 5, after releasing the connection 416 in the network associated with the first subscription 410, the UE 502 may create a new connection with the base station 404 in the network associated with the first subscription 410. For instance, at 614, the UE may perform a PDN connectivity procedure. For example, 614 may be performed by PDN connect component 752. For instance, referring to FIGs. 4 and 5, the

UE

402, 502 may perform PDN connectivity procedure 520 to set up a new EPS bearer to a PDN associated with the first subscription 410. Alternatively, at 616, the UE may perform a PDU session establishment procedure. For example, 616 may be performed by PDU session establish component 752. For instance, referring to FIGs. 4 and 5, the

UE

402, 502 may perform PDU session establishment procedure 522 to establish a new PDU session with the network associated with the first subscription 410.

FIG. 7 is a diagram 700 illustrating an example of a hardware implementation for an apparatus 702. The apparatus 702 is a UE and includes a cellular baseband processor 704 (also referred to as a modem) coupled to a cellular RF transceiver 722 and one or more subscriber identity modules (SIM) cards 720, an application processor 706 coupled to a secure digital (SD) card 708 and a screen 710, a Bluetooth module 712, a wireless local area network (WLAN) module 714, a Global Positioning System (GPS) module 716, and a power supply 718. The cellular baseband processor 704 communicates through the cellular RF transceiver 722 with the UE 104 and/or BS 102/180. The cellular baseband processor 704 may include a computer-readable medium /memory. The computer-readable medium /memory may be non-transitory. The cellular baseband processor 704 is responsible for general processing, including the execution of software stored on the computer-readable medium /memory. The software, when executed by the cellular baseband processor 704, causes the cellular baseband processor 704 to perform the various functions described supra. The computer-readable medium /memory may also be used for storing data that is manipulated by the cellular baseband processor 704 when executing software. The cellular baseband processor 704 further includes a reception component 730, a communication manager 732, and a transmission component 734. The communication manager 732 includes the one or more illustrated components. The components within the communication manager 732 may be stored in the computer-readable medium /memory and/or configured as hardware within the cellular baseband processor 704. The cellular baseband processor 704 may be a component of the UE 350 and may include the memory 360 and/or at least one of the TX processor 368, the RX processor 356, and the controller/processor 359. In one configuration, the apparatus 702 may be a modem chip and include just the baseband processor 704, and in another configuration, the apparatus 702 may be the entire UE (e.g., see 350 of FIG. 3) and include the aforediscussed additional modules of the apparatus 702.

The communication manager 732 includes a support component 740 that is configured to support a first connection associated with a first subscription and a second connection associated with a second subscription, where the first subscription comprises a dedicated data subscription, e.g., as described in connection with 602. The communication manager 732 further includes a switch component 742 that receives input in the form of the first subscription, second subscription, and dedicated data subscription from support component 740 and is configured to switch the dedicated data subscription from the first subscription to the second subscription, e.g., as described in connection with 604. The communication manager 732 further includes a disconnect component 744 that receives input in the form of the first connection from the support component 740 and is configured to disconnect the first connection following the switching by the switch component 742, e.g., as described in connection with 606. The communication manager 732 further includes a PDN disconnect component 746 that is configured to perform a PDN disconnect procedure, e.g., as described in connection with 608, and the communication manager 732 further includes a PDU session release component 748 that is configured to perform a PDU session release procedure, e.g., as described in connection with 610. The disconnect component 744 may include the PDN disconnect component 746 and the PDU session release component 748. The communication manager 732 further includes a reconnect component 750 that is configured to reconnect the first connection after the disconnecting by the disconnect component 744, e.g., as described in connection with 612. The communication manager 732 further includes a PDN connect component 752 that is configured to perform a PDN connectivity procedure, e.g., as described in connection with 614, and the communication manager 732 further includes a PDU session establish component 754 that is configured to perform a PDU session establishment procedure, e.g., as described in connection with 616. The reconnect component 750 may include the PDN connect component 752 and the PDU session establish component 754.

The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowcharts of FIGs. 5 and 6. As such, each block in the aforementioned flowcharts of FIGs. 5 and 6 may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof.

In one configuration, the apparatus 702, and in particular the cellular baseband processor 704, includes means for supporting a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription; means for switching the dedicated data subscription from the first subscription to the second subscription; and means for disconnecting the first connection following the switching.

In one configuration, the first subscription may be for a first SIM of the UE and the second subscription may be for a second SIM of the UE.

In one configuration, the first connection and the second connection may be to a base station.

In one configuration, the first connection and the second connection may be to different base stations.

In one configuration, the means for disconnecting may be further configured to perform a PDN disconnect procedure.

In one configuration, the means for disconnecting may be further configured to perform a PDU session release procedure.

In one configuration, the apparatus 702, and in particular the cellular baseband processor 704, may include means for reconnecting the first connection after the disconnecting. In one configuration, the means for reconnecting may be further configured to perform a PDN connectivity procedure. In one configuration, the means for reconnecting may be further configured to perform a PDU session establishment procedure.

The aforementioned means may be one or more of the aforementioned components of the apparatus 702 configured to perform the functions recited by the aforementioned means. As described supra, the apparatus 702 may include the TX Processor 368, the RX Processor 356, and the controller/processor 359. As such, in one configuration, the aforementioned means may be the TX Processor 368, the RX Processor 356, and the controller/processor 359 configured to perform the functions recited by the aforementioned means.

Further disclosure is included in the Appendix.

It is understood that the specific order or hierarchy of blocks in the processes /flowcharts disclosed is an illustration of example approaches. Based upon design preferences, it is understood that the specific order or hierarchy of blocks in the processes /flowcharts may be rearranged. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” Terms such as “if, ” “when, ” and “while” should be interpreted to mean “under the condition that” rather than imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when, ” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module, ” “mechanism, ” “element, ” “device, ” and the like may not be a substitute for the word “means. ” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for. ”

The following examples are illustrative only and may be combined with aspects of other embodiments or teachings described herein, without limitation.

Example 1 is a method of wireless communication at a user equipment (UE) , comprising: supporting a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription; switching the dedicated data subscription from the first subscription to the second subscription; and disconnecting the first connection following the switching.

Example 2 is the method of Example 1, wherein the first subscription is for a first subscriber identity module (SIM) of the UE and the second subscription is for a second SIM of the UE..

Example 3 is the method of Example 1 or 2, wherein the first connection and the second connection are to a base station.

Example 4 is the method of Example 1 or 2, wherein the first connection and the second connection are to different base stations.

Example 5 is the method of any of Examples 1 to 4, wherein the disconnecting comprises performing a packet data network (PDN) disconnect procedure.

Example 6 is the method of any of Examples 1 to 4, wherein the disconnecting comprises performing a protocol data unit (PDU) session release procedure.

Example 7 is the method of any of Examples 1 to 6, further comprising reconnecting the first connection after the disconnecting.

Example 8 is the method of Example 7, wherein the reconnecting comprises performing a packet data network (PDN) connectivity procedure.

Example 9 is the method of Example 7, wherein the reconnecting comprises performing a protocol data unit (PDU) session establishment procedure.

Example 10 is an apparatus for wireless communication, comprising: a processor; memory coupled with the processor; and instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to: support a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription; switch the dedicated data subscription from the first subscription to the second subscription; and disconnect the first connection following the switching.

Example 11 is the apparatus of Example 10, wherein the first subscription is for a first subscriber identity module (SIM) of the apparatus and the second subscription is for a second SIM of the apparatus.

Example 12 is the apparatus of Example 10 or 11, wherein the first connection and the second connection are to a base station.

Example 13 is the apparatus of Example 10 or 11, wherein the first connection and the second connection are to different base stations.

Example 14 is the apparatus of any of Examples 10 to 13, wherein the disconnecting comprises performing a packet data network (PDN) disconnect procedure.

Example 15 is the apparatus of any of Examples 10 to 13, wherein the disconnecting comprises performing a protocol data unit (PDU) session release procedure.

Example 16 is the apparatus of any of Examples 10 to 15, further comprising reconnecting the first connection after the disconnecting.

Example 17 is the apparatus of Example 16, wherein the reconnecting comprises performing a packet data network (PDN) connectivity procedure.

Example 18 is the apparatus of Example 16, wherein the reconnecting comprises performing a protocol data unit (PDU) session establishment procedure.

Example 19 is an apparatus for wireless communication, comprising: means for supporting a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription; means for switching the dedicated data subscription from the first subscription to the second subscription; and means for disconnecting the first connection following the switching.

Example 20 is the apparatus of Example 19, wherein the first subscription is for a first subscriber identity module (SIM) of the apparatus and the second subscription is for a second SIM of the apparatus.

Example 21 is the apparatus of Example 19 or 20, wherein the first connection and the second connection are to a base station.

Example 22 is the apparatus of Example 19 or 20, wherein the first connection and the second connection are to different base stations.

Example 23 is the apparatus of any of Examples 19 to 22, wherein the means for disconnecting is further configured to perform a packet data network (PDN) disconnect procedure.

Example 24 is the apparatus of any of Examples 19 to 22, wherein the means for disconnecting is further configured to perform a protocol data unit (PDU) session release procedure.

Example 25 is the apparatus of any of Examples 19 to 24, further comprising means for reconnecting the first connection after the disconnecting.

Example 26 is the apparatus of Example 25, wherein the means for reconnecting is further configured to perform a packet data network (PDN) connectivity procedure.

Example 27 is the apparatus of Example 25, wherein the means for reconnecting is further configured to perform a protocol data unit (PDU) session establishment procedure.

Example 28 is a computer-readable medium storing computer executable code, the code when executed by a processor cause the processor to: support a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription; switch the dedicated data subscription from the first subscription to the second subscription; and disconnect the first connection following the switching.

Example 29 is the computer-readable medium of Example 28, wherein the first subscription is for a first subscriber identity module (SIM) of the apparatus and the second subscription is for a second SIM of the apparatus.

Example 30 is the computer-readable medium of Example 28 or 29, wherein the code when executed by the processor further cause the processor to reconnect the first connection after the disconnecting.

Claims

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

supporting a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

switching the dedicated data subscription from the first subscription to the second subscription; and

disconnecting the first connection following the switching.
The method of claim 1, wherein the first subscription is for a first subscriber identity module (SIM) of the UE and the second subscription is for a second SIM of the UE.
The method of claim 1, wherein the first connection and the second connection are to a base station.
The method of claim 1, wherein the first connection and the second connection are to different base stations.
The method of claim 1, wherein the disconnecting comprises performing a packet data network (PDN) disconnect procedure.
The method of claim 1, wherein the disconnecting comprises performing a protocol data unit (PDU) session release procedure.
The method of claim 1, further comprising reconnecting the first connection after the disconnecting.
The method of claim 7, wherein the reconnecting comprises performing a packet data network (PDN) connectivity procedure.
The method of claim 7, wherein the reconnecting comprises performing a protocol data unit (PDU) session establishment procedure.
An apparatus for wireless communication, comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:

support a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

switch the dedicated data subscription from the first subscription to the second subscription; and

disconnect the first connection following the switching.
The apparatus of claim 10, wherein the first subscription is for a first subscriber identity module (SIM) of the apparatus and the second subscription is for a second SIM of the apparatus.
The apparatus of claim 10, wherein the first connection and the second connection are to a base station.
The apparatus of claim 10, wherein the first connection and the second connection are to different base stations.
The apparatus of claim 10, wherein the disconnecting comprises performing a packet data network (PDN) disconnect procedure.
The apparatus of claim 10, wherein the disconnecting comprises performing a protocol data unit (PDU) session release procedure.
The apparatus of claim 10, further comprising reconnecting the first connection after the disconnecting.
The apparatus of claim 16, wherein the reconnecting comprises performing a packet data network (PDN) connectivity procedure.
The apparatus of claim 16, wherein the reconnecting comprises performing a protocol data unit (PDU) session establishment procedure.
An apparatus for wireless communication, comprising:

means for supporting a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

means for switching the dedicated data subscription from the first subscription to the second subscription; and

means for disconnecting the first connection following the switching.
The apparatus of claim 19, wherein the first subscription is for a first subscriber identity module (SIM) of the apparatus and the second subscription is for a second SIM of the apparatus.
The apparatus of claim 19, wherein the first connection and the second connection are to a base station.
The apparatus of claim 19, wherein the first connection and the second connection are to different base stations.
The apparatus of claim 19, wherein the means for disconnecting is further configured to perform a packet data network (PDN) disconnect procedure.
The apparatus of claim 19, wherein the means for disconnecting is further configured to perform a protocol data unit (PDU) session release procedure.
The apparatus of claim 19, further comprising means for reconnecting the first connection after the disconnecting.
The apparatus of claim 25, wherein the means for reconnecting is further configured to perform a packet data network (PDN) connectivity procedure.
The apparatus of claim 25, wherein the means for reconnecting is further configured to perform a protocol data unit (PDU) session establishment procedure.
A computer-readable medium storing computer executable code, the code when executed by a processor cause the processor to:

support a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

switch the dedicated data subscription from the first subscription to the second subscription; and

disconnect the first connection following the switching.
The computer-readable medium of claim 28, wherein the first subscription is for a first subscriber identity module (SIM) of a user equipment (UE) and the second subscription is for a second SIM of the UE.
The computer-readable medium of claim 28, wherein the code when executed by the processor further cause the processor to reconnect the first connection after the disconnecting.
A method of wireless communication at a user equipment (UE) , comprising:

supporting a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

switching the dedicated data subscription from the first subscription to the second subscription; and

disconnecting the first connection following the switching.
The method of claim 31, wherein the first subscription is for a first subscriber identity module (SIM) of the UE and the second subscription is for a second SIM of the UE.
The method of claim 31 or 32, wherein the first connection and the second connection are to a base station.
The method of claim 31 or 32, wherein the first connection and the second connection are to different base stations.
The method of any of claims 31 to 34, wherein the disconnecting comprises performing a packet data network (PDN) disconnect procedure.
The method of any of claims 31 to 34, wherein the disconnecting comprises performing a protocol data unit (PDU) session release procedure.
The method of any of claims 31 to 36, further comprising reconnecting the first connection after the disconnecting.
The method of claim 37, wherein the reconnecting comprises performing a packet data network (PDN) connectivity procedure.
The method of claim 37, wherein the reconnecting comprises performing a protocol data unit (PDU) session establishment procedure.
An apparatus for wireless communication, comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:

support a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

switch the dedicated data subscription from the first subscription to the second subscription; and

disconnect the first connection following the switching.
The apparatus of claim 40, wherein the first subscription is for a first subscriber identity module (SIM) of the apparatus and the second subscription is for a second SIM of the apparatus.
The apparatus of claim 40 or 41, wherein the first connection and the second connection are to a base station.
The apparatus of claim 40 or 41, wherein the first connection and the second connection are to different base stations.
The apparatus of any of claims 40 to 43, wherein the disconnecting comprises performing a packet data network (PDN) disconnect procedure.
The apparatus of any of claims 40 to 43, wherein the disconnecting comprises performing a protocol data unit (PDU) session release procedure.
The apparatus of any of claims 40 to 45, further comprising reconnecting the first connection after the disconnecting.
The apparatus of claim 46, wherein the reconnecting comprises performing a packet data network (PDN) connectivity procedure.
The apparatus of claim 46, wherein the reconnecting comprises performing a protocol data unit (PDU) session establishment procedure.
An apparatus for wireless communication, comprising:

means for supporting a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

means for switching the dedicated data subscription from the first subscription to the second subscription; and

means for disconnecting the first connection following the switching.
The apparatus of claim 49, wherein the first subscription is for a first subscriber identity module (SIM) of the apparatus and the second subscription is for a second SIM of the apparatus.
The apparatus of claim 49 or 50, wherein the first connection and the second connection are to a base station.
The apparatus of claim 49 or 50, wherein the first connection and the second connection are to different base stations.
The apparatus of any of claims 49 to 52, wherein the means for disconnecting is further configured to perform a packet data network (PDN) disconnect procedure.
The apparatus of any of claims 49 to 52, wherein the means for disconnecting is further configured to perform a protocol data unit (PDU) session release procedure.
The apparatus of any of claims 49 to 54, further comprising means for reconnecting the first connection after the disconnecting.
The apparatus of claim 55, wherein the means for reconnecting is further configured to perform a packet data network (PDN) connectivity procedure.
The apparatus of claim 55, wherein the means for reconnecting is further configured to perform a protocol data unit (PDU) session establishment procedure.
A computer-readable medium storing computer executable code, the code when executed by a processor cause the processor to:

support a first connection associated with a first subscription and a second connection associated with a second subscription, wherein the first subscription comprises a dedicated data subscription;

switch the dedicated data subscription from the first subscription to the second subscription; and

disconnect the first connection following the switching.
The computer-readable medium of claim 58, wherein the first subscription is for a first subscriber identity module (SIM) of a user equipment (UE) and the second subscription is for a second SIM of the UE.
The computer-readable medium of claim 58 or 59, wherein the code when executed by the processor further cause the processor to reconnect the first connection after the disconnecting.