WO2019183944A1

WO2019183944A1 - Internet based nas signaling connection

Info

Publication number: WO2019183944A1
Application number: PCT/CN2018/081403
Authority: WO
Inventors: Jie Mao; Zhanyi Liu; Shiau-He Tsai; Insung Kang
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2018-03-30
Filing date: 2018-03-30
Publication date: 2019-10-03
Anticipated expiration: 2020-09-30

Abstract

Methods, apparatuses and non-transitory computer-readable media are described. A method for a scheduled entity includes: receiving one or more non-access stratum (NAS) signals of a mobile communication network through a data path that includes at least an Internet Protocol (IP) based network; and communicating with the mobile communication network based on the received one or more NAS signals.

Description

INTERNET BASED NAS SIGNALING CONNECTION

TECHNICAL FIELD

The technology discussed below relates generally to wireless communication systems, and more particularly, to an Internet-based non-access stratum (NAS) signaling connection.

INTRODUCTION

As the demand for mobile broadband access continues to increase, research and development continue to advance wireless communication technologies not only to meet the growing demand for mobile broadband access, but to advance and enhance the user experience with mobile communications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a wireless communication system.

FIG. 2 is a conceptual illustration of an example of a radio access network.

FIG. 3 is a schematic illustration of an organization of wireless resources in an air interface utilizing orthogonal frequency divisional multiplexing (OFDM) .

FIG. 4 is a block diagram conceptually illustrating an example of a hardware implementation for a scheduling entity according to some aspects of the disclosure.

FIG. 5 is a block diagram conceptually illustrating an example of a hardware implementation for a scheduled entity according to some aspects of the disclosure.

FIG. 6 is an exemplary network architecture in accordance with various aspects of the present disclosure.

FIG. 7 is an exemplary network architecture in accordance with various aspects of the present disclosure.

FIG. 8 illustrates an exemplary heartbeat procedure in a network architecture in accordance with various aspects of the present disclosure.

FIG. 9 is an exemplary network architecture in accordance with various aspects of the present disclosure.

FIG. 10 is an exemplary network architecture in accordance with various aspects of the present disclosure.

FIG. 11 is an exemplary network architecture in accordance with various aspects of the present disclosure.

FIG. 12 illustrates an example signal flow diagram in accordance with various aspects of the disclosure.

FIG. 13 illustrates an example signal flow diagram in accordance with various aspects of the disclosure.

FIG. 14 illustrates an example signal flow diagram in accordance with various aspects of the disclosure.

FIG. 15 is a flow chart illustrating an exemplary process according to some aspects of the disclosure.

FIG. 16 is a flow chart illustrating an exemplary process according to some aspects of the disclosure.

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.

While aspects and embodiments are described in this application by illustration to some examples, those skilled in the art will understand that additional implementations and use cases may come about in many different arrangements and scenarios. Innovations described herein may be implemented across many differing platform types, devices, systems, shapes, sizes, packaging arrangements. For example, embodiments and/or uses may come about via integrated chip embodiments and other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, AI-enabled devices, etc. ) . While some examples may or may not be specifically directed to use cases or applications, a wide assortment of applicability of described innovations may occur. Implementations may range a spectrum from chip-level or modular components to non-modular, non-chip-level implementations and further to aggregate, distributed, or OEM devices or systems incorporating one or more aspects of the described innovations. In some practical settings, devices incorporating described aspects and features may also necessarily include additional components and features for implementation and practice of claimed and described embodiments. For example, transmission and reception of wireless signals necessarily includes a number of components for analog and digital purposes (e.g., hardware components including antenna, RF-chains, power amplifiers, modulators, buffer, processor (s) , interleaver, adders/summers, etc. ) . It is intended that innovations described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, end-user devices, etc. of varying sizes, shapes and constitution.

DEFINITIONS

RAT: radio access technology. The type of technology or communication standard utilized for radio access and communication over a wireless air interface. Just a few examples of RATs include GSM, UTRA, E-UTRA (LTE) , Bluetooth, and Wi-Fi.

NR: new radio. Generally refers to 5G technologies and the new radio access technology undergoing definition and standardization by 3GPP in Release 15.

AS: access stratum. A functional grouping consisting of the parts in the radio access network and in the UE, and the protocols between these parts being specific to the access technique (i.e., the way the specific physical media between the UE and the radio access network is used to carry information) .

NAS: non-access stratum. Protocols between UE and the core network that are not terminated in the radio access network.

RAB: radio access bearer. The service that the access stratum provides to the non-access stratum for transfer of user information between a UE and the core network.

The various concepts presented throughout this disclosure may be implemented across a broad variety of telecommunication systems, network architectures, and communication standards. Referring now to FIG. 1, as an illustrative example without limitation, various aspects of the present disclosure are illustrated with reference to a wireless communication system 100. The wireless communication system 100 includes three interacting domains: a core network 102, a radio access network (RAN) 104, and a user equipment (UE) 106. By virtue of the wireless communication system 100, the UE 106 may be enabled to carry out data communication with an external data network 110, such as (but not limited to) the Internet (also referred to as an Internet network) .

The RAN 104 may implement any suitable wireless communication technology or technologies to provide radio access to the UE 106. As one example, the RAN 104 may operate according to 3rd Generation Partnership Project (3GPP) New Radio (NR) specifications, often referred to as 5G. As another example, the RAN 104 may operate under a hybrid of 5G NR and Evolved Universal Terrestrial Radio Access Network (eUTRAN) standards, often referred to as LTE. The 3GPP refers to this hybrid RAN as a next-generation RAN, or NG-RAN. Of course, many other examples may be utilized within the scope of the present disclosure.

As illustrated, the RAN 104 includes a plurality of base stations 108. Broadly, a base station is a network element in a radio access network responsible for radio transmission and reception in one or more cells to or from a UE. In different technologies, standards, or contexts, a base station may variously be referred to by those skilled in the art as a base transceiver station (BTS) , a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS) , an extended service set (ESS) , an access point (AP) , a Node B (NB) , an eNode B (eNB) , a gNode B (gNB) , or some other suitable terminology.

The radio access network 104 is further illustrated supporting wireless communication for multiple mobile apparatuses. A mobile apparatus may be referred to as user equipment (UE) in 3GPP standards, but may also be referred to by those skilled in the art as a mobile station (MS) , 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 (AT) , a mobile terminal, a wireless terminal, a remote terminal, a handset, a terminal, a user agent, a mobile client, a client, or some other suitable terminology. A UE may be an apparatus that provides a user with access to network services.

Within the present document, a “mobile” apparatus need not necessarily have a capability to move, and may be stationary. The term mobile apparatus or mobile device broadly refers to a diverse array of devices and technologies. UEs may include a number of hardware structural components sized, shaped, and arranged to help in communication; such components can include antennas, antenna arrays, RF chains, amplifiers, one or more processors, etc. electrically coupled to each other. For example, some non-limiting examples of a mobile apparatus include a mobile, a cellular (cell) phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal computer (PC) , a notebook, a netbook, a smartbook, a tablet, a personal digital assistant (PDA) , and a broad array of embedded systems, e.g., corresponding to an “Internet of things” (IoT) . A mobile apparatus may additionally be an automotive or other transportation vehicle, a remote sensor or actuator, a robot or robotics device, a satellite radio, a global positioning system (GPS) device, an object tracking device, a drone, a multi-copter, a quad-copter, a remote control device, a consumer and/or wearable device, such as eyewear, a wearable camera, a virtual reality device, a smart watch, a health or fitness tracker, a digital audio player (e.g., MP3 player) , a camera, a game console, etc. A mobile apparatus may additionally be a digital home or smart home device such as a home audio, video, and/or multimedia device, an appliance, a vending machine, intelligent lighting, a home security system, a smart meter, etc. A mobile apparatus may additionally be a smart energy device, a security device, a solar panel or solar array, a municipal infrastructure device controlling electric power (e.g., a smart grid) , lighting, water, etc.; an industrial automation and enterprise device; a logistics controller; agricultural equipment; military defense equipment, vehicles, aircraft, ships, and weaponry, etc. Still further, a mobile apparatus may provide for connected medicine or telemedicine support, e.g., health care at a distance. Telehealth devices may include telehealth monitoring devices and telehealth administration devices, whose communication may be given preferential treatment or prioritized access over other types of information, e.g., in terms of prioritized access for transport of critical service data, and/or relevant QoS for transport of critical service data.

Wireless communication between a RAN 104 and a UE 106 may be described as utilizing an air interface. Transmissions over the air interface from a base station (e.g., base station 108) to one or more UEs (e.g., UE 106) may be referred to as downlink (DL) transmission. In accordance with certain aspects of the present disclosure, the term downlink may refer to a point-to-multipoint transmission originating at a scheduling entity (described further below; e.g., base station 108) . Another way to describe this scheme may be to use the term broadcast channel multiplexing. Transmissions from a UE (e.g., UE 106) to a base station (e.g., base station 108) may be referred to as uplink (UL) transmissions. In accordance with further aspects of the present disclosure, the term uplink may refer to a point-to-point transmission originating at a scheduled entity (described further below; e.g., UE 106) .

In some examples, access to the air interface may be scheduled, wherein a scheduling entity (e.g., a base station 108) allocates resources for communication among some or all devices and equipment within its service area or cell. Within the present disclosure, as discussed further below, the scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more scheduled entities. That is, for scheduled communication, UEs 106, which may be scheduled entities, may utilize resources allocated by the scheduling entity 108.

Base stations 108 are not the only entities that may function as scheduling entities. That is, in some examples, a UE may function as a scheduling entity, scheduling resources for one or more scheduled entities (e.g., one or more other UEs) .

As illustrated in FIG. 1, a scheduling entity 108 may broadcast downlink traffic 112 to one or more scheduled entities 106. Broadly, the scheduling entity 108 is a node or device responsible for scheduling traffic in a wireless communication network, including the downlink traffic 112 and, in some examples, uplink traffic 116 from one or more scheduled entities 106 to the scheduling entity 108. On the other hand, the scheduled entity 106 is a node or device that receives downlink control information 114, including but not limited to scheduling information (e.g., a grant) , synchronization or timing information, or other control information from another entity in the wireless communication network such as the scheduling entity 108.

In general, base stations 108 may include a backhaul interface for communication with a backhaul portion 120 of the wireless communication system. The backhaul 120 may provide a link between a base station 108 and the core network 102. Further, in some examples, a backhaul network may provide interconnection between the respective base stations 108. Various types of backhaul interfaces may be employed, such as a direct physical connection, a virtual network, or the like using any suitable transport network.

The core network 102 may be a part of the wireless communication system 100, and may be independent of the radio access technology used in the RAN 104. In some examples, the core network 102 may be configured according to 5G standards (e.g., 5GC) . In other examples, the core network 102 may be configured according to a 4G evolved packet core (EPC) , or any other suitable standard or configuration.

Referring now to FIG. 2, by way of example and without limitation, a schematic illustration of a RAN 200 is provided. In some examples, the RAN 200 may be the same as the RAN 104 described above and illustrated in FIG. 1. The geographic area covered by the RAN 200 may be divided into cellular regions (cells) that can be uniquely identified by a user equipment (UE) based on an identification broadcasted from one access point or base station. FIG. 2 illustrates

macrocells

202, 204, and 206, and a small cell 208, each of which may include one or more sectors (not shown) . A sector is a sub-area of a cell. All sectors within one cell are served by the same base station. A radio link within a sector can be identified by a single logical identification belonging to that sector. In a cell that is divided into sectors, the multiple sectors within a cell can be formed by groups of antennas with each antenna responsible for communication with UEs in a portion of the cell.

In FIG. 2, two base stations 210 and 212 are shown in

cells

202 and 204; and a third base station 214 is shown controlling a remote radio head (RRH) 216 in cell 206. That is, a base station can have an integrated antenna or can be connected to an antenna or RRH by feeder cables. In the illustrated example, the

cells

202, 204, and 126 may be referred to as macrocells, as the

base stations

210, 212, and 214 support cells having a large size. Further, a base station 218 is shown in the small cell 208 (e.g., a microcell, picocell, femtocell, home base station, home Node B, home eNode B, etc. ) which may overlap with one or more macrocells. In this example, the cell 208 may be referred to as a small cell, as the base station 218 supports a cell having a relatively small size. Cell sizing can be done according to system design as well as component constraints.

It is to be understood that the radio access network 200 may include any number of wireless base stations and cells. Further, a relay node may be deployed to extend the size or coverage area of a given cell. The

base stations

210, 212, 214, 218 provide wireless access points to a core network for any number of mobile apparatuses. In some examples, the

base stations

210, 212, 214, and/or 218 may be the same as the base station/scheduling entity 108 described above and illustrated in FIG. 1.

FIG. 2 further includes a quadcopter or drone 220, which may be configured to function as a base station. That is, in some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile base station such as the quadcopter 220.

Within the RAN 200, the cells may include UEs that may be in communication with one or more sectors of each cell. Further, each

base station

210, 212, 214, 218, and 220 may be configured to provide an access point to a core network 102 (see FIG. 1) for all the UEs in the respective cells. For example,

UEs

222 and 224 may be in communication with base station 210;

UEs

226 and 228 may be in communication with base station 212;

UEs

230 and 232 may be in communication with base station 214 by way of RRH 216; UE 234 may be in communication with base station 218; and UE 236 may be in communication with mobile base station 220. In some examples, the

UEs

222, 224, 226, 228, 230, 232, 234, 236, 238, 240, and/or 242 may be the same as the UE/scheduled entity 106 described above and illustrated in FIG. 1.

In some examples, a mobile network node (e.g., quadcopter 220) may be configured to function as a UE. For example, the quadcopter 220 may operate within cell 202 by communicating with base station 210.

In a further aspect of the RAN 200, sidelink signals may be used between UEs without necessarily relying on scheduling or control information from a base station. For example, two or more UEs (e.g., UEs 226 and 228) may communicate with each other using peer to peer (P2P) or sidelink signals 227 without relaying that communication through a base station (e.g., base station 212) . In a further example, UE 238 is illustrated communicating with

UEs

240 and 242. Here, the UE 238 may function as a scheduling entity or a primary sidelink device, and

UEs

240 and 242 may function as a scheduled entity or a non-primary (e.g., secondary) sidelink device. In still another example, a UE may function as a scheduling entity in a device-to-device (D2D) , peer-to-peer (P2P) , or vehicle-to-vehicle (V2V) network, and/or in a mesh network. In a mesh network example,

UEs

240 and 242 may optionally communicate directly with one another in addition to communicating with the scheduling entity 238. Thus, in a wireless communication system with scheduled access to time-frequency resources and having a cellular configuration, a P2P configuration, or a mesh configuration, a scheduling entity and one or more scheduled entities may communicate utilizing the scheduled resources.

In the radio access network 200, the ability for a UE to communicate while moving, independent of its location, is referred to as mobility. The various physical channels between the UE and the radio access network are generally set up, maintained, and released under the control of an access and mobility management function (AMF, not illustrated, part of the core network 102 in FIG. 1) , which may include a security context management function (SCMF) that manages the security context for both the control plane and the user plane functionality, and a security anchor function (SEAF) that performs authentication.

In various aspects of the disclosure, a radio access network 200 may utilize DL-based mobility or UL-based mobility to enable mobility and handovers (i.e., the transfer of a UE’s connection from one radio channel to another) . In a network configured for DL-based mobility, during a call with a scheduling entity, or at any other time, a UE may monitor various parameters of the signal from its serving cell as well as various parameters of neighboring cells. Depending on the quality of these parameters, the UE may maintain communication with one or more of the neighboring cells. During this time, if the UE moves from one cell to another, or if signal quality from a neighboring cell exceeds that from the serving cell for a given amount of time, the UE may undertake a handoff or handover from the serving cell to the neighboring (target) cell. For example, UE 224 (illustrated as a vehicle, although any suitable form of UE may be used) may move from the geographic area corresponding to its serving cell 202 to the geographic area corresponding to a neighbor cell 206. When the signal strength or quality from the neighbor cell 206 exceeds that of its serving cell 202 for a given amount of time, the UE 224 may transmit a reporting message to its serving base station 210 indicating this condition. In response, the UE 224 may receive a handover command, and the UE may undergo a handover to the cell 206.

In a network configured for UL-based mobility, UL reference signals from each UE may be utilized by the network to select a serving cell for each UE. In some examples, the

base stations

210, 212, and 214/216 may broadcast unified synchronization signals (e.g., unified Primary Synchronization Signals (PSSs) , unified Secondary Synchronization Signals (SSSs) and unified Physical Broadcast Channels (PBCH) ) . The

UEs

222, 224, 226, 228, 230, and 232 may receive the unified synchronization signals, derive the carrier frequency and slot timing from the synchronization signals, and in response to deriving timing, transmit an uplink pilot or reference signal. The uplink pilot signal transmitted by a UE (e.g., UE 224) may be concurrently received by two or more cells (e.g., base stations 210 and 214/216) within the radio access network 200. Each of the cells may measure a strength of the pilot signal, and the radio access network (e.g., one or more of the base stations 210 and 214/216 and/or a central node within the core network) may determine a serving cell for the UE 224. As the UE 224 moves through the radio access network 200, the network may continue to monitor the uplink pilot signal transmitted by the UE 224. When the signal strength or quality of the pilot signal measured by a neighboring cell exceeds that of the signal strength or quality measured by the serving cell, the network 200 may handover the UE 224 from the serving cell to the neighboring cell, with or without informing the UE 224.

Although the synchronization signal transmitted by the

base stations

210, 212, and 214/216 may be unified, the synchronization signal may not identify a particular cell, but rather may identify a zone of multiple cells operating on the same frequency and/or with the same timing. The use of zones in 5G networks or other next generation communication networks enables the uplink-based mobility framework and improves the efficiency of both the UE and the network, since the number of mobility messages that need to be exchanged between the UE and the network may be reduced.

In various implementations, the air interface in the radio access network 200 may utilize licensed spectrum, unlicensed spectrum, or shared spectrum. Licensed spectrum provides for exclusive use of a portion of the spectrum, generally by virtue of a mobile network operator purchasing a license from a government regulatory body. Unlicensed spectrum provides for shared use of a portion of the spectrum without need for a government-granted license. While compliance with some technical rules is generally still required to access unlicensed spectrum, generally, any operator or device may gain access. Shared spectrum may fall between licensed and unlicensed spectrum, wherein technical rules or limitations may be required to access the spectrum, but the spectrum may still be shared by multiple operators and/or multiple RATs. For example, the holder of a license for a portion of licensed spectrum may provide licensed shared access (LSA) to share that spectrum with other parties, e.g., with suitable licensee-determined conditions to gain access.

Various aspects of the present disclosure will be described with reference to an OFDM waveform, schematically illustrated in FIG. 3. It should be understood by those of ordinary skill in the art that the various aspects of the present disclosure may be applied to a DFT-s-OFDMA waveform in substantially the same way as described herein below. That is, while some examples of the present disclosure may focus on an OFDM link for clarity, it should be understood that the same principles may be applied as well to DFT-s-OFDMA waveforms.

Within the present disclosure, a frame refers to a duration of 10 ms for wireless transmissions, with each frame consisting of 10 subframes of 1 ms each. On a given carrier, there may be one set of frames in the UL, and another set of frames in the DL. Referring now to FIG. 3, an expanded view of an exemplary DL subframe 302 is illustrated, showing an OFDM resource grid 304. However, as those skilled in the art will readily appreciate, the PHY transmission structure for any particular application may vary from the example described here, depending on any number of factors. Here, time is in the horizontal direction with units of OFDM symbols; and frequency is in the vertical direction with units of subcarriers or tones.

The resource grid 304 may be used to schematically represent time-frequency resources for a given antenna port. That is, in a MIMO implementation with multiple antenna ports available, a corresponding multiple number of resource grids 304 may be available for communication. The resource grid 304 is divided into multiple resource elements (REs) 306. An RE, which is 1 subcarrier × 1 symbol, is the smallest discrete part of the time-frequency grid, and contains a single complex value representing data from a physical channel or signal. Depending on the modulation utilized in a particular implementation, each RE may represent one or more bits of information. In some examples, a block of REs may be referred to as a physical resource block (PRB) or more simply a resource block (RB) 308, which contains any suitable number of consecutive subcarriers in the frequency domain. In one example, an RB may include 12 subcarriers, a number independent of the numerology used. In some examples, depending on the numerology, an RB may include any suitable number of consecutive OFDM symbols in the time domain. Within the present disclosure, it is assumed that a single RB such as the RB 308 entirely corresponds to a single direction of communication (either transmission or reception for a given device) .

A UE generally utilizes only a subset of the resource grid 304. An RB may be the smallest unit of resources that can be allocated to a UE. Thus, the more RBs scheduled for a UE, and the higher the modulation scheme chosen for the air interface, the higher the data rate for the UE.

In this illustration, the RB 308 is shown as occupying less than the entire bandwidth of the subframe 302, with some subcarriers illustrated above and below the RB 308. In a given implementation, the subframe 302 may have a bandwidth corresponding to any number of one or more RBs 308. Further, in this illustration, the RB 308 is shown as occupying less than the entire duration of the subframe 302, although this is merely one possible example.

Each 1 ms subframe 302 may consist of one or multiple adjacent slots. In the example shown in FIG. 3, one subframe 302 includes four slots 310, as an illustrative example. In some examples, a slot may be defined according to a specified number of OFDM symbols with a given cyclic prefix (CP) length. For example, a slot may include 7 or 14 OFDM symbols with a nominal CP. Additional examples may include mini-slots having a shorter duration (e.g., one or two OFDM symbols) . These mini-slots may in some cases be transmitted occupying resources scheduled for ongoing slot transmissions for the same or for different UEs.

An expanded view of one of the slots 310 illustrates the slot 310 including a control region 312 and a data region 314. In general, the control region 312 may carry control channels (e.g., PDCCH) , and the data region 314 may carry data channels (e.g., PDSCH or PUSCH) . Of course, a slot may contain all DL, all UL, or at least one DL portion and at least one UL portion. The simple structure illustrated in FIG. 3 is merely exemplary in nature, and different slot structures may be utilized, and may include one or more of each of the control region (s) and data region (s) .

Although not illustrated in FIG. 3, the various REs 306 within a RB 308 may be scheduled to carry one or more physical channels, including control channels, shared channels, data channels, etc. Other REs 306 within the RB 308 may also carry pilots or reference signals, including but not limited to a demodulation reference signal (DMRS) a control reference signal (CRS) , or a sounding reference signal (SRS) . These pilots or reference signals may provide for a receiving device to perform channel estimation of the corresponding channel, which may enable coherent demodulation/detection of the control and/or data channels within the RB 308.

In a DL transmission, the transmitting device (e.g., the scheduling entity 108) may allocate one or more REs 306 (e.g., within a control region 312) to carry DL control information 114 including one or more DL control channels, such as a PBCH; a PSS; a SSS; a physical control format indicator channel (PCFICH) ; a physical hybrid automatic repeat request (HARQ) indicator channel (PHICH) ; and/or a physical downlink control channel (PDCCH) , etc., to one or more scheduled entities 106. The PCFICH provides information to assist a receiving device in receiving and decoding the PDCCH. The PDCCH carries downlink control information (DCI) including but not limited to power control commands, scheduling information, a grant, and/or an assignment of REs for DL and UL transmissions. The PHICH carries HARQ feedback transmissions such as an acknowledgment (ACK) or negative acknowledgment (NACK) . HARQ is a technique well-known to those of ordinary skill in the art, wherein the integrity of packet transmissions may be checked at the receiving side for accuracy, e.g., utilizing any suitable integrity checking mechanism, such as a checksum or a cyclic redundancy check (CRC) . If the integrity of the transmission confirmed, an ACK may be transmitted, whereas if not confirmed, a NACK may be transmitted. In response to a NACK, the transmitting device may send a HARQ retransmission, which may implement chase combining, incremental redundancy, etc.

In an UL transmission, the transmitting device (e.g., the scheduled entity 106) may utilize one or more REs 306 to carry UL control information 118 including one or more UL control channels, such as a physical uplink control channel (PUCCH) , to the scheduling entity 108. UL control information may include a variety of packet types and categories, including pilots, reference signals, and information configured to enable or assist in decoding uplink data transmissions. In some examples, the control information 118 may include a scheduling request (SR) , e.g., a request for the scheduling entity 108 to schedule uplink transmissions. Here, in response to the SR transmitted on the control channel 118, the scheduling entity 108 may transmit downlink control information 114 that may schedule resources for uplink packet transmissions. UL control information may also include HARQ feedback, channel state feedback (CSF) , or any other suitable UL control information.

In addition to control information, one or more REs 306 (e.g., within the data region 314) may be allocated for user data or traffic data. Such traffic may be carried on one or more traffic channels, such as, for a DL transmission, a physical downlink shared channel (PDSCH) ; or for an UL transmission, a physical uplink shared channel (PUSCH) . In some examples, one or more REs 306 within the data region 314 may be configured to carry system information blocks (SIBs) , carrying information that may enable access to a given cell.

The channels or carriers described above and illustrated in FIGs. 1 and 3 are not necessarily all the channels or carriers that may be utilized between a scheduling entity 108 and scheduled entities 106, and those of ordinary skill in the art will recognize that other channels or carriers may be utilized in addition to those illustrated, such as other traffic, control, and feedback channels.

These physical channels described above are generally multiplexed and mapped to transport channels for handling at the medium access control (MAC) layer. Transport channels carry blocks of information called transport blocks (TB) . The transport block size (TBS) , which may correspond to a number of bits of information, may be a controlled parameter, based on the modulation and coding scheme (MCS) and the number of RBs in a given transmission.

FIG. 4 is a block diagram illustrating an example of a hardware implementation for a scheduling entity 400 employing a processing system 414. For example, the scheduling entity 400 may be a base station as illustrated in any one or more of FIGs. 1 and/or 2.

The scheduling entity 400 may be implemented with a processing system 414 that includes one or more processors 404. Examples of processors 404 include microprocessors, microcontrollers, digital signal processors (DSPs) , 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. In various examples, the scheduling entity 400 may be configured to perform any one or more of the functions described herein.

In this example, the processing system 414 may be implemented with a bus architecture, represented generally by the bus 402. The bus 402 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 414 and the overall design constraints. The bus 402 communicatively couples together various circuits including one or more processors (represented generally by the processor 404) , a memory 405, and computer-readable media (represented generally by the computer-readable medium 406) . The bus 402 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further. A bus interface 408 provides an interface between the bus 402 and a transceiver 410. The transceiver 410 provides a communication interface or means for communicating with various other apparatus over a transmission medium. Depending upon the nature of the apparatus, a user interface 412 (e.g., keypad, display, speaker, microphone, joystick) may also be provided. Of course, such a user interface 412 is optional, and may be omitted in some examples, such as a base station. In some aspects of the disclosure, the processor 404 may include circuitry (e.g., circuits 400, 442) configured for the various functions described herein.

The processor 404 is responsible for managing the bus 402 and general processing, including the execution of software stored on the computer-readable medium 406. The software, when executed by the processor 404, causes the processing system 414 to perform the various functions described below for any particular apparatus. The computer-readable medium 406 and the memory 405 may also be used for storing data that is manipulated by the processor 404 when executing software.

One or more processors 404 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 modules, 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. The software may reside on a computer-readable medium 406. The computer-readable medium 406 may be a non-transitory computer-readable medium. A non-transitory computer-readable medium includes, by way of example, a magnetic storage device (e.g., hard disk, floppy disk, magnetic strip) , an optical disk (e.g., a compact disc (CD) or a digital versatile disc (DVD) ) , a smart card, a flash memory device (e.g., a card, a stick, or a key drive) , a random access memory (RAM) , a read only memory (ROM) , a programmable ROM (PROM) , an erasable PROM (EPROM) , an electrically erasable PROM (EEPROM) , a register, a removable disk, and any other suitable medium for storing software and/or instructions that may be accessed and read by a computer. The computer-readable medium 406 may reside in the processing system 414, external to the processing system 414, or distributed across multiple entities including the processing system 414. The computer-readable medium 406 may be embodied in a computer program product. By way of example, a computer program product may include a computer-readable medium in packaging materials. Those skilled in the art will recognize how best to implement the described functionality presented throughout this disclosure depending on the particular application and the overall design constraints imposed on the overall system.

In one or more examples, the computer-readable storage medium 406 may include software (e.g., the instructions 452, 454) configured for the various functions described herein.

FIG. 5 is a conceptual diagram illustrating an example of a hardware implementation for an exemplary scheduled entity 500 employing a processing system 514. In accordance with various aspects of the disclosure, an element, or any portion of an element, or any combination of elements may be implemented with a processing system 514 that includes one or more processors 504. For example, the scheduled entity 500 may be a user equipment (UE) as illustrated in any one or more of FIGs. 1 and/or 2.

The processing system 514 may be substantially the same as the processing system 414 illustrated in FIG. 4, including a bus interface 508, a bus 502, memory 505, a processor 504, and a computer-readable medium 506. Furthermore, the scheduled entity 500 may include a user interface 512 and a transceiver 510 substantially similar to those described above in FIG. 4. That is, the processor 504, as utilized in a scheduled entity 500, may be used to implement any one or more of the processes described below and illustrated in FIG. 15.

In some aspects of the disclosure, the processor 504 may include circuitry configured for the various functions described herein. For example, the circuitry (e.g., circuit 540, 542) may be configured to implement one or more of the functions described below in relation to FIG. 15.

In one or more examples, the computer-readable storage medium 506 may include software (e.g., the instructions 552, 554) configured for the various functions described herein.

A scheduled entity (e.g., a UE) that subscribes to multiple networks (e.g., different mobile communication networks using different subscriber identity modules (SIMs) ) may fail to receive NAS signals (e.g., paging requests) from one network when using its radio to connect to other networks. This may occur due to paging occurrence conflicts with respect to the multiple networks. Therefore, a first subscription (Sub1) of the scheduled entity may experience a degradation in performance (e.g., scheduling penalty, NW/UE out of sync, etc. ) when tuning away to another network. Moreover, frequent location area updates (LAUs) and/or tracking area updates (TAUs) in a second subscription (Sub2) of the scheduled entity may contribute to further performance degradation. In some aspects of the disclosure, heavy signaling procedures (e.g., procedures that may consume a substantial amount of network resources) , such as LAU, TAU, attach, detach, etc., may be transmitted via an Internet-based signaling connection on Sub1 to avoid the performance impact to Sub1.

For example, the operator (Sub1) of the first network may avoid throughput degradation and/or avoid missing a mobile terminated (MT) call, while the operator (Sub2) of the second network may reduce the signaling load. The approaches described herein may provide a “power saving” mode for a base station. The operator (Sub2) of the second network may also avoid missing an MT call. An MT incoming call in Sub2 may be notified to a user even if Sub1 is in a circuit-switched (CS) call. A user of the scheduled entity may experience performance improvement in Sub1 and Sub2 when one or more of the disclosed aspects are implemented. Power savings may be achieved by reducing paging monitoring, measurements in idle in Sub2, etc. In some aspects, the Internet-based signaling approaches described herein may be setup on Wifi, or NB-IOT which may have better coverage than LTE or 5G NR in some scenarios. This may further improve the reliability (e.g., with respect to receiving NAS signals at the scheduled entity) in some emergency scenarios

FIG. 6 is an exemplary network architecture 600 in accordance with various aspects of the present disclosure. As shown in FIG. 6, the network architecture 600 may include a scheduled entity 602, an external IP based network (e.g., Internet 604) , an Internet-based NAS signaling (IbNS) server 606, and a core network 608. As further shown in FIG. 6, the scheduled entity 602 may be configured to implement a protocol stack 603. In some aspects of the disclosure, the protocol stack 603 may include an application layer, an Internet-based NAS signaling (IbNS) client 612, a NAS layer 614, a radio resource control (RRC) layer 616, an L2 layer 618 (also referred to as a data link layer 618) , and a physical (PHY) layer 620. In some aspects of the disclosure, the core network 608 may be a 5G Next Generation Core (5G NGC) or an Evolved Packet Core (EPC) .

The IbNS server 606 and the IbNS client 612 may be configured to implement a protocol that enables communication of messages (e.g., NAS signaling) between one another over the Internet 604. In some aspects of the disclosure, the IbNS server 606 and the IbNS client 612 may be configured to perform a discovery and registration operation (e.g., over the Internet 604) that enables the IbNS client 612 to find the IbNS server 606 and to connect to the IbNS server 606. The scheduled entity 602 may indicate to the IbNS server 606 that paging requests from the core network 608 intended for the scheduled entity 602 are to be delivered to the scheduled entity 602 via the IbNS server 606 and the Internet 604. In some aspects of the disclosure, the IbNS server 606 and the IbNS client 612 may be further configured to perform a security procedure as an IP Multimedia Subsystem (IMS) (e.g., existing IMS functions may be upgraded to support the function) . In some aspects of the disclosure, the IbNS server 606 and the core network 608 may implement a new interface that supports communication between the IbNS server 606 and the core network 608. After the registration operation between the IbNS client 612 and the IbNS server 606 is completed, the IbNS server 606 may perform a registration operation with the core network 608. The IbNS server 606 may indicate to the core network 608 that paging requests intended for the scheduled entity 602 are to be sent to the IbNS server 606. The IbNS server 606 may then forward the paging requests received from the core network 608 to the scheduled entity 602 via the Internet 604.

FIG. 7 is an exemplary network architecture 700 in accordance with various aspects of the present disclosure. As shown in FIG. 7, the network architecture 700 may include a scheduled entity 702, an external IP based network (e.g., Internet 704) , an Internet-based NAS signaling (IbNS) server 706, and a core network 708. In some aspects of the disclosure, the scheduled entity 702, the Internet 704, the Internet-based NAS signaling (IbNS) server 706, and the core network 708 shown in FIG. 7 may respectively correspond to the scheduled entity 602, the Internet 604, the IbNS server 606, and the core network 608 shown in FIG. 6. In the example configuration of FIG. 7, the network architecture 700 may include

cells

710a, 710b,

cells

712a, 712b, 712c, and an Internet coverage area 714. In some aspects of the disclosure, the

cells

710a, 710b may be part of a first network (e.g., a first wireless wide area network (WWAN) ) , the

cells

712a, 712b, 712c, may be part of a second network (e.g., a second WWAN) , and the Internet coverage area 714 may be served by an Internet access node (e.g., a Wifi access point, a Narrowband IoT (NB-IoT) ) access point, etc. ) . In some aspects of the disclosure, the scheduled entity 702 may support multiple network subscriptions. For example, the scheduled entity 702 may include a first subscription (also referred to as Subscription 1 or Sub1) that enables the scheduled entity 702 to connect to the first network and a second subscription (also referred to as Subscription 2 or Sub2) that enables the scheduled entity 702 to connect to the second network. In such example, the scheduled entity 702 may include a first subscriber identity module (SIM 1) for the first subscription and a second subscriber identity module (SIM 2) for the second subscription.

In the example configuration of FIG. 7, the core network 708 may be part of the second network and, therefore, may be configured to service the

cells

712a, 712b, 712c. In FIG. 7, the core network 708 and the

cells

712a, 712b, 712c are similarly shaded to facilitate identification of items corresponding to the second network. The

cells

710a, 710b may be served by a core network (not shown in FIG. 7 for ease of illustration) of the first network. In the example configuration of FIG. 7, some of the cells of the first and second networks may be overlapping. For example, cell 712a may overlap cell 710a.

In one example scenario, and as shown in FIG. 7, the scheduled entity 702 may be located in the cell 710a (of the first network) and may initiate an IbNS registration operation with the IbNS server 706. This IbNS registration operation may indicate to the IbNS server 706 that the scheduled entity 702 is able to support the previously described Internet-based NAS signaling. In an aspect of the disclosure, the scheduled entity 702 may initiate the IbNS registration operation by transmitting an IbNS registration message 716 to the IbNS server 706. In an aspect of the disclosure, the IbNS registration message 716 may indicate to the IbNS server 706 that paging requests from the core network 708 intended for the scheduled entity 702 are to be delivered to the scheduled entity 702 via the IbNS server 706 and the Internet 704. After receiving the IbNS registration message 716, the IbNS server 706 may transmit an IbNS registration message 720 to the core network 708 to register the scheduled entity 702 to the core network 708. In an aspect of the disclosure, the IbNS registration message 720 may indicate to the core network 708 that paging requests intended for the scheduled entity 702 are to be delivered to the scheduled entity 702 via the IbNS server 706 and the Internet 704. The IbNS server 706 may then establish a connection between the scheduled entity 702 and the core network 708 via the IbNS server 706. In some aspects of the disclosure, the IbNS server 706 may also set up a security context that may be used to protect (e.g., encrypt, integrity protect, etc. ) communications between the core network 708 and the scheduled entity 702 over the Internet 704. In some aspects of the disclosure, the IbNS server 706 may complete an attach procedure following the IbNS registration operation.

FIG. 8 illustrates an exemplary heartbeat procedure in the network architecture 700 in accordance with various aspects of the present disclosure. As shown In FIG. 8, after the scheduled entity 702 has registered with the IbNS server 706, the scheduled entity 702 may transmit one or more heartbeat messages (also referred to as heartbeat signals) , such as the heartbeat message 818, to the IbNS server 706. In some aspects of the disclosure, the heartbeat message 818 may indicate to the IbNS server 706 that the scheduled entity 702 is online (e.g., that the scheduled entity 702 is still connected to the IbNS server 706 and that messages can reach the scheduled entity 702) . In some aspects of the disclosure, the heartbeat message 818 may serve as a tracking area update signal. For example, the IbNS server 706 may receive the heartbeat message 818 and, in response, may transmit a tracking area update message 820 to the core network 708. In some aspects of the disclosure, the tracking area update message 820 may trigger a tracking area update (TAU) procedure at the core network 708. In other aspects of the disclosure, the tracking area update message 820 may update the core network 708 with the status (e.g., the current tracking area) of the scheduled entity 702. In some aspects of the disclosure, the heartbeat message 818 may be used to consolidate the heartbeat procedure of high level applications (e.g., instant messaging (IM) applications) running on the scheduled entity 702.

FIG. 9 is an exemplary network architecture 900 in accordance with various aspects of the present disclosure. As shown in FIG. 9, the network architecture 900 may include a scheduled entity 902, a wireless access node 904, a first scheduling entity 906 (also referred to as scheduling entity_1 906) , a first core network 908 (also referred to as core network_1 908) , a second scheduling entity 910 (also referred to as scheduling entity_2 910) , a second core network 912 (also referred to as core network_2 912) , an Internet-based NAS signaling (IbNS) server 914, and an external IP based network (e.g., Internet 916) . The IbNS server disclosed herein may be implemented as a network node. For example, such network node may include at least a processing system (e.g., one or more processors, a computer readable medium, memory, etc. ) and a transceiver that is configured to perform the operation and functions described herein. As further shown in FIG. 9, the scheduled entity 902 may include a processing system 918, a transceiver 920, a first subscription 924 (also referred to as Subscription 1 924) , and a second subscription 926 (also referred to as Subscription 2 926) . In some aspects of the disclosure, the processing system 918 may be configured to implement a protocol stack 928, which may include an application layer 930, an Internet-based NAS signaling (IbNS) client 932, a NAS layer 934, a radio resource control (RRC) layer 936, an L2 layer 938 (also referred to as a data link layer 938) , and a physical (PHY) layer 940.

In some aspects of the disclosure, the scheduling entity_1 906 and the core network_1 908 may be part of a first network (e.g., an LTE or 5G network operated by a first network operator) and the scheduling entity_2 910 and the core network_2 912 may be part of a second network (e.g., an LTE or 5G network operated by a second network operator) . In some aspects of the disclosure, the core network_1 908 may be either an EPC or a 5G NGC and the scheduling entity_1 906 may be a suitably configured base station (e.g., an eNB or a gNB) . In some aspects of the disclosure, the core network_2 912 may be either an EPC or a 5G NGC and the scheduling entity_2 910 may be a suitably configured base station (e.g., an eNB or a gNB) . In some aspects of the disclosure, the wireless access node 904 may include or more devices configured to provide wireless internet access to the scheduled entity 902. For example, the wireless access node 904 may include a WiFi access point and/or an NB-IOT access point. The transceiver 920 may include one or more antennas and corresponding circuitry for wireless communication with the wireless access node 904, the scheduling entity 1_906, and/or the scheduling entity 2_910. In some aspects of the disclosure, subscription 1 924 may be implemented with a first subscriber identity module (SIM 1) and subscription 2 926 may be implemented with a second subscriber identity module (SIM 2) .

FIG. 10 is an exemplary network architecture 1000 in accordance with various aspects of the present disclosure. As shown in FIG. 10, the network architecture 1000 may include the previously described scheduled entity 902, wireless access node 904, scheduling entity_1 906, core network_1 908, scheduling entity_2 910, core network_2 912, IbNS server 914, and Internet 916. In the example configuration of FIG. 10, the scheduling entity_1 906 and the core network_1 908 may be configured to service the

cells

1002a, 1002b, and the scheduling entity_2 910 and the core network_2 912 may be configured to service the

cells

1004a, 1004b, 1004c. In FIG. 7, the scheduling entity_2 910, the core network_2 912, and the

cells

1004a, 1004b, 1004c are similarly shaded to facilitate identification of items corresponding to the second network. In the example configuration of FIG. 10, some of the cells of the first and second networks may be overlapping. For example, cell 1004a may overlap cell 1002a.

In one example scenario, and as shown in FIG. 10, the scheduled entity 902 may be located in the cell 1002a (of the first network) . The scheduled entity 902 may register with IbNS server 914 as previously discussed with reference to FIG. 7. In some scenarios, the scheduled entity 902 may enter an idle mode (e.g., RRC idle mode) after registering with IbNS server 914. In some aspects of the disclosure, the core network_2 912 may attempt to transmit NAS signals (e.g., a paging request 1a in a message 1008) to the scheduled entity 902 via the scheduled entity_2 910. In other aspects of the disclosure, the core network_2 912 may be configured to transmit a paging request to the scheduled entity 902 via the Internet 916. In such aspects of the disclosure, for example, the core network_2 912 may transmit a paging request 1b in a message 1010 to the IbNS server 914. The IbNS server 914 may then forward the paging request 1b in a data service packet to the scheduled entity 902 via the Internet 916. For example, as indicated with the path 1012 (e.g., shown as a dashed line in FIG. 10) , the core network_1 908 may receive the data service packet including the paging request 1b and may forward the data service packet including the paging request 1b to the scheduling entity_1 906 for delivery to the scheduled entity 902.

In another example scenario, and as shown in FIG. 11, the scheduled entity 902 may be located in the Internet coverage area 1006. The scheduled entity 902 may register with IbNS server 914 as previously discussed with reference to FIG. 7. In some scenarios, the scheduled entity 902 may enter an idle mode (e.g., RRC idle mode) after registering with IbNS server 914. In some aspects of the disclosure, the core network_2 912 may attempt to transmit NAS signals (e.g., a paging request 1a in a message 1108) to the scheduled entity 902 via the scheduled entity_2 910. In other aspects of the disclosure, the core network_2 912 may be configured to transmit a paging request to the scheduled entity 902 via the Internet 916. In such aspects of the disclosure, for example, the core network_2 912 may transmit a paging request 1b in a message 1010 to the IbNS server 914. The IbNS server 914 may then forward the paging request 1b in a data service packet to the scheduled entity 902 via the Internet 916. For example, as indicated with the path 1112 (e.g., shown as a dashed line in FIG. 11) , the wireless access node 904 may receive the data service packet including the paging request 1b and may forward the data service packet including the paging request 1b to the scheduled entity 902.

FIG. 12 illustrates an example signal flow diagram 1200 in accordance with various aspects of the disclosure. For example, the signal flow diagram 1200 may be applied to the exemplary network architecture 1000 shown in FIG. 10. As shown in FIG. 12, the scheduled entity 902 may perform an IbNS server registration operation 1202 with the IbNS server 914. The scheduled entity 902 may enter an RRC idle mode 1204. The core network_2 912 may transmit a paging request 1a (e.g., intended for the scheduled entity 902) to the scheduling entity_2 910 in a message 1208. The scheduling entity_2 910 may forward the paging request 1a to the scheduled entity 902 in a message 1214. When the core network_2 912 is configured to transmit paging requests via the Internet 916, the core network_2 912 may transmit a paging request 1b (e.g., a redundant paging request) to the IbNS server 914 in a message 1210. For example, the core network_2 912 may be configured by the IbNS server 914 to transmit paging requests via the Internet 916 as described in detail herein. The IbNS server 914 may transmit a message 1216 including the paging request 1b to the scheduled entity 902 via the Internet 916. In an aspect, the message 1216 may be a data service packet. The core network_1 908 may receive a message 1218 including the paging request 1b from the Internet 916. In order to deliver the message 1218 (e.g., a data service packet) to the scheduled entity 902, the core network_1 908 may transmit a message 1220 including a page signal to the scheduling entity_1 906. The scheduling entity_1 906 may forward the page signal to the scheduled entity 902 in a message 1222. In response to the page signal in the message 1222, the scheduled entity 902 may establish an RRC connection 1224 with the scheduling entity_1 906. The core network_1 908 may forward a message 1226 including the paging request 1b to the scheduling entity_1 906, which may then forward the paging request 1b to the scheduled entity 902 in a message 1228. It should be noted that the paging request 1b from the core network_2 912 (e.g., in the message 1210) may arrive at the scheduled entity 902 via the path 1012 previously described with reference to FIG. 10. The message 1228 may be decoded by the IbNS client 932 of the scheduled entity 902 to obtain the paging request 1b.

In some scenarios, there may be periods (e.g., the period 1250) during which the scheduled entity 902 may only need to monitor paging messages on the first network and perform measurements associated with the first network. In such scenarios, the scheduled entity 902 may not need to monitor paging messages or perform LAU/TAU procedures with respect to the second network. Therefore, the scheduled entity 902 may be tuned away from the second network (e.g., the scheduling entity_2 910) during the period 1250 and may not receive the message 1214 including the paging request 1a. In these scenarios, when the core network_2 912 attempts to page the scheduled entity 902 to set up a connection for an incoming call (e.g., a mobile-terminated call) , the scheduled entity 902 may not receive the paging signal from the first network and therefore may miss the incoming call. However, since the scheduled entity 902 may be monitoring the first network (e.g., the scheduling entity_1 906) during the period 1250, the scheduled entity 902 may receive the paging request 1b in the message 1228 via the first network (e.g., the scheduling entity_1 906) .

In one example scenario, after receiving the paging request 1b, the scheduled entity 902 may fall back 1230 (e.g., perform a circuit-switched fall back operation) to the second network. Accordingly, after the scheduled entity 902 camps on the second network, the scheduled entity 902 may transmit a message 1232 including a paging response to the scheduling entity_2 910. The scheduled entity 902 may then establish an RRC connection 1234 with the scheduling entity_2 910 to receive the incoming call.

In some aspects of the disclosure, while the scheduled entity 902 may not be required to monitor the second network during the period 1250, the scheduled entity 902 may perform measurements with respect to the second network (e.g., the scheduling entity_2 910) . In these aspects, when the scheduled entity 902 falls back 1230 to the second network, the scheduled entity 902 may have information as to which cell in the second network may provide the strongest signal. Therefore, after the scheduled entity 902 receives the paging request 1b via the Internet 916, the scheduled entity 902 may immediately select the cell that provides the strongest signal in the second network. Otherwise, upon falling back 1230 to the second network, the scheduled entity 902 may need to take the time to perform measurements with respect to the second network in order to identify a cell in the second network that provides an adequate signal. This may result in additional delays before the scheduled entity 902 may camp on a cell in the second network and proceed to set up the incoming call associated with the paging request 1b.

FIG. 13 illustrates an example signal flow diagram 1300 in accordance with various aspects of the disclosure. For example, the signal flow diagram 1300 may be applied to the exemplary network architecture 1000 shown in FIG. 11. As shown in FIG. 13, the scheduled entity 902 may perform an IbNS server registration operation 1302 with the IbNS server 914. The scheduled entity 902 may enter an RRC idle mode 1304. The core network_2 912 may transmit a paging request 1a to the scheduling entity_2 910 in a message 1308. The scheduling entity_2 910 may forward the paging request 1a to the scheduled entity 902 in a message 1314. When the core network_2 912 is configured to transmit paging requests via the Internet 916, the core network_2 912 may transmit a paging request 1b to the IbNS server 914 in a message 1310. For example, the core network_2 912 may be configured by the IbNS server 914 to transmit paging requests via the Internet 916 as described in detail herein. The IbNS server 914 may transmit a message 1316 including the paging request 1b to the scheduled entity 902 via the Internet 916. In an aspect, the message 1316 may be a data service packet. A message 1318 including the paging request 1b may be routed to the wireless access node 904, which may deliver a message 1320 including the paging request 1b to the scheduled entity 902. It should be noted that the paging request 1b from the core network_2 912 (e.g., in the message 1310) may arrive at the scheduled entity 902 via the path 1112 previously described with reference to FIG. 11. The message 1320 may be decoded by the IbNS client 932 of the scheduled entity 902 to obtain the paging request 1b.

In some scenarios, as previously discussed with reference to FIG. 12, there may be periods (e.g., the period 1350) during which the scheduled entity 902 may only need to monitor paging messages on the first network and perform measurements associated with the first network. In such scenarios, the scheduled entity 902 may not need to monitor paging messages or perform LAU/TAU procedures with respect to the second network. Therefore, the scheduled entity 902 may be tuned away from the second network (e.g., the scheduling entity_2 910) during the period 1350 and may not receive the message 1314 including the paging request 1a. In these scenarios, when the core network_2 912 attempts to page the scheduled entity 902 to set up a connection for an incoming call (e.g., a mobile-terminated call) , the scheduled entity 902 may not receive the paging signal from the first network and therefore may miss the incoming call. However, since the scheduled entity 902 may receive the message 1320 including the paging request 1b from the wireless access node 904, the scheduled entity 902 may receive the paging request 1b transmitted by the core network_2 910 while monitoring the first network.

In one example scenario, after receiving the paging request 1b, the scheduled entity 902 may fall back 1330 to the second network. Accordingly, after the scheduled entity 902 camps on the second network, the scheduled entity 902 may transmit a message 1332 including a paging response to the scheduling entity_2 910. The scheduled entity 902 may then establish an RRC connection 1334 with the scheduling entity_2 910 to receive the incoming call.

In some aspects of the disclosure, while the scheduled entity 902 may not be required to monitor the second network during the period 1350, the scheduled entity 902 may perform measurements with respect to the second network (e.g., the scheduling entity_2 910) . In these aspects, when the scheduled entity 902 falls back 1330 to the second network, the scheduled entity 902 may have information as to which cell in the second network may provide the strongest signal. Therefore, after the scheduled entity 902 receives the paging request 1b via the Internet 916, the scheduled entity 902 may immediately select the cell that provides the strongest signal in the second network.

Although the previously described exemplary signal flow diagrams 1200 and 1300 are described with respect to paging requests, it should be understood that the approaches disclosed in these signal flow diagrams may be applied to other types of NAS signaling (e.g., signaling for a tracking area update procedure as described below with reference to FIG. 14) . Therefore, a NAS signaling procedure may be completed via the Internet-based signaling approaches described herein. It can be appreciated that aspects described herein may provide redundant paging requests (e.g., paging requests 1a and 1b in FIGS. 13 and 14) via the Internet (e.g., Internet 916) to reduce paging failure rates. Since the redundant paging requests may be communicated to a scheduled entity via WiFi or NB-IOT in some aspects, implementation of these technologies may provide better coverage than LTE or 5G NR and, therefore, may improve network reliability in some emergency scenarios. In some aspects of the disclosure, the NAS signaling for both the first network (e.g., subscription 1) and the second network (e.g., subscription 2) may be communicated via NB-IOT to achieve greater power savings. In some aspects of the disclosure, multiple redundant paging messages may be provided to the scheduled entity 902. For example, the scheduled entity 902 may receive a redundant paging request (e.g., paging request 1b) via the Internet 916 from both the scheduling entity_1 906 (e.g., the message 1228) and the wireless access node 904 (e.g., the message 1320) .

In some aspects of the disclosure, the scheduled entity 902 may receive a paging request (e.g., the paging request 1b in FIG. 13) via the Internet 916 over an NB-IoT connection (e.g., in aspects where the wireless access node 904 includes an NB-IoT access point) . Such NB-IoT connection may provide better coverage (e.g., higher signal strength) than a 5G connection. Therefore, in one example, a scheduled entity 902 in an area with poor 5G signal reception (e.g., when the scheduled entity 902 is located in an underground garage or basement) may be able to obtain a paging request (e.g., the paging request 1b in FIG. 13) , but may not be able to establish a connection with the 5G network to setup the incoming call associated with the paging request. In these scenarios, the scheduled entity 902 may alert a user that an incoming call was detected. The user of the scheduled entity 902 may then relocate to an area with adequate 5G network coverage and may place a call to the party that initiated the paging request.

FIG. 14 illustrates an example signal flow diagram 1400 in accordance with various aspects of the disclosure. For example, the signal flow diagram 1400 may be applied to the exemplary network architecture 1000 shown in FIGS. 10 and 11. As shown in FIG. 14, the scheduled entity 902 may perform an IbNS server registration operation 1402 with the IbNS server 914. The scheduled entity 902 may enter an RRC idle mode 1404. In one approach (e.g., Option 1 in FIG. 14) , the scheduled entity 902 may transmit a message 1406 including a heartbeat 1a to the IbNS server 914. The scheduling entity_1 906 may receive the message 1406 and may transmit a message 1408 including the heartbeat 1a to the core network_1 908. The core network_1 908 may transmit a message 1410 including the heartbeat 1a to the IbNS server 914 via the Internet 916. The IbNS server 914 may receive a message 1412 including the heartbeat 1a from the Internet 916. The IbNS server 914 may decode the message 1412 to obtain the heartbeat 1a. In some aspects of the disclosure, the IbNS server 914 may transmit a message 1414 including a tracking area update (TAU) 1a to the core network_2 912. In another approach (e.g., Option 2 in FIG. 14) , the scheduled entity 902 may transmit a message 1454 including a heartbeat 1b to the IbNS server 914. The message 1454 including the heartbeat 1b may be received by the wireless access node 904, which may forward the heartbeat 1b to the IbNS server 914 via the Internet 916 in a message 1456. The IbNS server 914 may receive a message 1458 including the heartbeat 1b from the Internet 916. The IbNS server 914 may decode the message 1458 to obtain the heartbeat 1b. In some aspects of the disclosure, the IbNS server 914 may transmit a message 1460 including a tracking area update (TAU) 1b to the core network_2 912. In some aspects of the disclosure, the IbNS server 914 may initiate a TAU procedure with the core network_2 912.

In some aspects of the disclosure, when scheduled entity 902 determines that it is entering a new tracking area and that a TAU procedure is need, the scheduled entity 902 may determine whether it has registered with the IbNS server 914. If the scheduled entity 902 has registered with the IbNS server 914, the scheduled entity 902 may initiate a TAU procedure via the IbNS 914 instead of setting up a NAS signaling connection in the second network (e.g., for subscription 2) .

In some aspects of the disclosure, the scheduled entity 902 may transmit the message 1406 including the heartbeat 1a and/or the message 1454 including the heartbeat 1b to the IbNS server 914, where the heartbeat 1a and/or the heartbeat 1b includes information to be delivered from the IbNS server 914 to the core network2 912. In such aspects, the information to be delivered to the core network_2 912 may enable the core network_2 912 to perform one or more NAS procedures. For example, the one or more NAS procedures may include a security context maintenance, a home subscriber server (HSS) context maintenance (e.g., when the scheduled entity 902 is away from its Home Public Land Mobile Network) , and/or other suitable NAS procedures. In some aspects of the disclosure, the core network_2 912 may perform the HSS context maintenance when the scheduled entity 902 is roaming. In some aspects of the disclosure, the one or more NAS procedures may be performed during periods when the scheduled entity 902 is in the RRC idle mode 1404.

FIG. 15 is a flow chart illustrating an exemplary process 1500 in accordance with some aspects of the present disclosure. As described below, some or all illustrated features may be omitted in a particular implementation within the scope of the present disclosure, and some illustrated features may not be required for implementation of all embodiments. In some examples, the process 1500 may be carried out by the scheduled entity 500 illustrated in FIG. 5. In some examples, the process 1500 may be carried out by any suitable apparatus or means for carrying out the functions or algorithm described below. In FIG. 15, operations indicated with dashed lines represent optional operations.

At block 1502, the scheduled entity receives one or more non-access stratum (NAS) signals of a mobile communication network through a data path that includes at least an Internet Protocol (IP) based network. At block 1504, the scheduled entity may monitor one or more signals of a second mobile communication network, wherein the one or more NAS signals are received during the monitoring of the one or more signals. At block 1506, the scheduled entity may perform one or more measurements with respect to the mobile communication network, wherein the NAS signals are received during the performing of the one or more measurements. At block 1508, the scheduled entity may communicate with the mobile communication network based on the received one or more NAS signals. At block 1510, the scheduled entity may detect that the scheduled entity has entered a new tracking area. At block 1512, the scheduled entity may transmit one or more heartbeat messages to the Internet-based NAS signaling server, wherein one or more heartbeat messages initiates a tracking area update procedure between the Internet-based NAS signaling server and a core network of the mobile communication network. At block 1514, the scheduled entity may transmit one or more heartbeat messages to the Internet-based NAS signaling server, wherein the one or more heartbeat messages includes information to be delivered from the Internet-based NAS signaling server to a core network of the mobile communication network, and wherein the information enables the core network to perform one or more NAS procedures. In some aspects of the disclosure, the one or more NAS procedures includes at least a security context maintenance or a home subscriber server (HSS) context maintenance. In some aspects of the disclosure, the HSS context maintenance is performed when the scheduled entity is roaming.

In one configuration, the apparatus 500 for wireless communication includes means for performing the operation and functions described in detail herein. In one aspect, the aforementioned means may be the processor 504 shown in FIG. 5 configured to perform the functions recited by the aforementioned means. In another aspect, the aforementioned means may be a circuit or any apparatus configured to perform the functions recited by the aforementioned means.

Of course, in the above examples, the circuitry included in the processor 504 is merely provided as an example, and other means for carrying out the described functions may be included within various aspects of the present disclosure, including but not limited to the instructions stored in the computer-readable storage medium 506, or any other suitable apparatus or means described in any one of the FIGs. 1 and/or 2, and utilizing, for example, the processes and/or algorithms described herein in relation to FIG. 15.

FIG. 16 is a flow chart illustrating an exemplary process 1600 in accordance with some aspects of the present disclosure. As described below, some or all illustrated features may be omitted in a particular implementation within the scope of the present disclosure, and some illustrated features may not be required for implementation of all embodiments. In some examples, the process 1600 may be carried out by the IbNS server (e.g.,

IbNS server

606, 706, 914) disclosed herein. In some examples, the process 1600 may be carried out by any suitable apparatus or means for carrying out the functions or algorithm described below. In Fig. 16, operations indicated with dashed lines represent optional operations.

At block 1602, the IbNS server receives a registration message from the scheduled entity. At block 1604, the IbNS server indicates to a core network of the mobile communication network that paging requests for the scheduled entity are to be transmitted to the Internet-based NAS signaling server. At block 1606, the IbNS server receives one or more non-access stratum (NAS) signals of a mobile communication network. At block 1608, the IbNS server transmits, to a scheduled entity, the one or more NAS signals through a data path that includes at least an Internet Protocol (IP) based network. At block 1610, the IbNS server receives one or more heartbeat messages from the scheduled entity. At block 1612, the IbNS server initiates a tracking area update procedure with a core network of the mobile communication network in response to the receiving of the one or more heartbeat messages. At block 1614, the IbNS server receives one or more heartbeat messages from the scheduled entity, wherein the one or more heartbeat messages includes information to be delivered to a core network of the mobile communication network, and wherein the information enables the core network to perform one or more NAS procedures. In some aspects of the disclosure, the one or more NAS procedures includes at least a security context maintenance or an HSS context maintenance. In some aspects of the disclosure, the HSS context maintenance is performed when the scheduled entity is roaming.

Several aspects of a wireless communication network have been presented with reference to an exemplary implementation. As those skilled in the art will readily appreciate, various aspects described throughout this disclosure may be extended to other telecommunication systems, network architectures and communication standards.

By way of example, various aspects may be implemented within other systems defined by 3GPP, such as Long-Term Evolution (LTE) , the Evolved Packet System (EPS) , the Universal Mobile Telecommunication System (UMTS) , and/or the Global System for Mobile (GSM) . Various aspects may also be extended to systems defined by the 3rd Generation Partnership Project 2 (3GPP2) , such as CDMA2000 and/or Evolution-Data Optimized (EV-DO) . Other examples may be implemented within systems employing IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Ultra-Wideband (UWB) , Bluetooth, and/or other suitable systems. The actual telecommunication standard, network architecture, and/or communication standard employed will depend on the specific application and the overall design constraints imposed on the system.

Within the present disclosure, the word “exemplary” is used to mean “serving as an example, instance, or illustration. ” Any implementation or aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects of the disclosure. Likewise, the term “aspects” does not require that all aspects of the disclosure include the discussed feature, advantage or mode of operation. The term “coupled” is used herein to refer to the direct or indirect coupling between two objects. For example, if object A physically touches object B, and object B touches object C, then objects A and C may still be considered coupled to one another-even if they do not directly physically touch each other. For instance, a first object may be coupled to a second object even though the first object is never directly physically in contact with the second object. The terms “circuit” and “circuitry” are used broadly, and intended to include both hardware implementations of electrical devices and conductors that, when connected and configured, enable the performance of the functions described in the present disclosure, without limitation as to the type of electronic circuits, as well as software implementations of information and instructions that, when executed by a processor, enable the performance of the functions described in the present disclosure.

One or more of the components, steps, features and/or functions illustrated in FIGs. 1-16 may be rearranged and/or combined into a single component, step, feature or function or embodied in several components, steps, or functions. Additional elements, components, steps, and/or functions may also be added without departing from novel features disclosed herein. The apparatus, devices, and/or components illustrated in FIGs. 1-16 may be configured to perform one or more of the methods, features, or steps escribed herein. The novel algorithms described herein may also be efficiently implemented in software and/or embedded in hardware.

It is to be understood that the specific order or hierarchy of steps in the methods disclosed is an illustration of exemplary processes. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the methods may be rearranged. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented unless specifically recited therein.

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 are to be accorded the full scope consistent with the language of the 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. ” Unless specifically stated otherwise, the term “some” refers to one or more. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover: a; b; c; a and b; a and c; b and c; and a, b and 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. No claim element is to be construed under the provisions of 35 U.S.C. §112 (f) unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for. ”

Claims

A method for a scheduled entity, comprising:

receiving one or more non-access stratum (NAS) signals of a mobile communication network through a data path that includes at least an Internet Protocol (IP) based network; and

communicating with the mobile communication network based on the received one or more NAS signals.
The method of claim 1, further comprising:

monitoring one or more signals of a second mobile communication network, wherein the one or more NAS signals are received during the monitoring of the one or more signals.
The method of claim 1, further comprising:

performing one or more measurements with respect to the mobile communication network, wherein the one or more NAS signals are received during the performing of the one or more measurements.
The method of claim 1, wherein the one or more NAS signals are received from a wireless access node that provides access to the IP based network.
The method of claim 1, wherein the data path further includes at least a core network and a scheduling entity of a second mobile communication network, and wherein the one or more NAS signals are received from the scheduling entity of the second mobile communication network.
The method of claim 1, wherein the one or more NAS signals include at least one paging request.
The method of claim 6, wherein the communicating with the mobile communication network based on the received one or more NAS signals comprises:

falling back to the mobile communication network in response to the at least one paging request;

transmitting a paging response to the mobile communication network; and

setting up a mobile terminated call with the mobile communication network.
The method of claim 7, wherein the falling back comprises selecting a cell of the mobile communication network based on one or more measurements performed with respect to the mobile communication network prior to receiving the one or more NAS signals.
The method of claim 1, wherein the data path further includes an Internet-based NAS signaling server, and wherein the receiving the one or more NAS signals of the mobile communication network comprises:

receiving a message generated by the Internet-based NAS signaling server, the message including the one or more NAS signals; and

using an Internet-based NAS signaling client at the scheduled entity to obtain the one or more NAS signals from the message.
The method of claim 1, wherein the data path further includes an Internet-based NAS signaling server, further comprising:

detecting that the scheduled entity has entered a new tracking area;

transmitting one or more heartbeat messages to the Internet-based NAS signaling server, wherein one or more heartbeat messages initiates a tracking area update procedure between the Internet-based NAS signaling server and a core network of the mobile communication network.
The method of claim 1, wherein the data path further includes an Internet-based NAS signaling server, further comprising:

transmitting one or more heartbeat messages to the Internet-based NAS signaling server, wherein the one or more heartbeat messages includes information to be delivered from the Internet-based NAS signaling server to a core network of the mobile communication network, and wherein the information enables the core network to perform one or more NAS procedures.
The method of claim 11, wherein the one or more NAS procedures includes at least a security context maintenance or a home subscriber server (HSS) context maintenance.
The method of claim 12, wherein the HSS context maintenance is performed when the scheduled entity is roaming.
An apparatus for wireless communication, comprising:

means for receiving one or more non-access stratum (NAS) signals of a mobile communication network through a data path that includes at least an Internet Protocol (IP) based network; and

means for communicating with the mobile communication network based on the received one or more NAS signals.
A non-transitory computer-readable medium storing computer-executable code, comprising code for causing a computer to:

receive one or more non-access stratum (NAS) signals of a mobile communication network through a data path that includes at least an Internet Protocol (IP) based network; and

communicate with the mobile communication network based on the received one or more NAS signals.
An apparatus for wireless communication, comprising:

a processor;

a transceiver communicatively coupled to the at least one processor; and

a memory communicatively coupled to the at least one processor,

wherein the processor is configured to:

receive one or more non-access stratum (NAS) signals of a mobile communication network through a data path that includes at least an Internet Protocol (IP) based network; and

communicate with the mobile communication network based on the received one or more NAS signals.
A method, comprising:

receiving one or more non-access stratum (NAS) signals of a mobile communication network; and

transmitting, to a scheduled entity, the one or more NAS signals through a data path that includes at least an Internet Protocol (IP) based network.
The method of claim 17, wherein the one or more NAS signals are received from a core network of the mobile communication network.
The method of claim 17, wherein the data path further includes at least a core network and a scheduling entity of a second mobile communication network.
The method of claim 17, wherein the one or more NAS signals include at least one paging request.
The method of claim 17, further comprising:

receiving, at an Internet-based NAS signaling server, a registration message from the scheduled entity; and

indicating to a core network of the mobile communication network that paging requests for the scheduled entity are to be transmitted to the Internet-based NAS signaling server.
The method of claim 17, further comprising:

receiving one or more heartbeat messages from the scheduled entity;

initiating a tracking area update procedure with a core network of the mobile communication network in response to the receiving of the one or more heartbeat messages.
The method of claim 17, further comprising:

receiving one or more heartbeat messages from the scheduled entity, wherein the one or more heartbeat messages includes information to be delivered to a core network of the mobile communication network, and wherein the information enables the core network to perform one or more NAS procedures.
The method of claim 23, wherein the one or more NAS procedures includes at least a security context maintenance or a home subscriber server (HSS) context maintenance.
The method of claim 24, wherein the HSS context maintenance is performed when the scheduled entity is roaming.
An apparatus for wireless communication, comprising:

means for receiving one or more non-access stratum (NAS) signals of a mobile communication network; and

means for transmitting, to a scheduled entity, the one or more NAS signals through a data path that includes at least an Internet Protocol (IP) based network.
A non-transitory computer-readable medium storing computer-executable code, comprising code for causing a computer to:

receive one or more non-access stratum (NAS) signals of a mobile communication network; and

transmit, to a scheduled entity, the one or more NAS signals through a data path that includes at least an Internet Protocol (IP) based network.
An apparatus for wireless communication, comprising:

a processor;

a transceiver communicatively coupled to the at least one processor; and

a memory communicatively coupled to the at least one processor,

wherein the processor is configured to:

receive one or more non-access stratum (NAS) signals of a mobile communication network; and

transmit, to a scheduled entity, the one or more NAS signals through a data path that includes at least an Internet Protocol (IP) based network.