WO2020069115A1

WO2020069115A1 - Backhaul signaling for notification and coordination in remote interference management

Info

Publication number: WO2020069115A1
Application number: PCT/US2019/053136
Authority: WO
Inventors: Hassan GHOZLAN; Qian Li; Dawei YING; Geng Wu
Original assignee: Intel Corporation
Priority date: 2018-09-28
Filing date: 2019-09-26
Publication date: 2020-04-02
Also published as: EP3857744A1; EP3857744A4

Abstract

This application relates an apparatus for remote interference management (RIM) by a first next generation Node-B(gNB) in a wireless communication system. Backhaul signaling is provided for notification and coordination among gNBs in a next generation system for remote interference management.

Description

BACKHAUL SIGNALING FOR NOTIFICATION AND COORDINATION IN REMOTE

INTERFERENCE MANAGEMENT

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 62/739,060, filed September 28, 2018, which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

[0002] This application relates generally to wireless communication systems, and more specifically to remote interference management.

BACKGROUND

[0003] Wireless mobile communication technology uses various standards and protocols to transmit data between a base station and a wireless mobile device. Wireless communication system standards and protocols can include the 3rd Generation Partnership Project (3GPP) long term evolution (LTE); the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard, which is commonly known to industry groups as worldwide interoperability for microwave access (WiMAX); and the IEEE 802.11 standard for wireless local area networks (WLAN), which is commonly known to industry groups as Wi-Fi. In 3GPP radio access networks (RANs) in LTE systems, the base station can include a RAN Node such as a Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (also commonly denoted as evolved Node B, enhanced Node B, eNodeB, or eNB) and/or Radio Network Controller (RNC) in an E-UTRAN, which communicate with a wireless communication device, known as user equipment (UE). In fifth generation (5G) wireless RANs, RAN Nodes can include a 5G Node, new radio (NR) node or g Node B (gNB).

[0004] RANs use a radio access technology (RAT) to communicate between the RAN Node and UE. RANs can include global system for mobile communications (GSM), enhanced data rates for GSM evolution (EDGE) RAN (GERAN), Universal Terrestrial Radio Access Network (UTRAN), and/or E-UTRAN, which provide access to communication services through a core network. Each of the RANs operates according to a specific 3GPP RAT. For example, the GERAN implements GSM and/or EDGE RAT, the UTRAN implements universal mobile telecommunication system (UMTS) RAT or other 3 GPP RAT, and the E-UTRAN implements LTE RAT.

[0005] A core network can be connected to the UE through the RAN Node. The core network can include a serving gateway (SGW), a packet data network (PDN) gateway (PGW), an access network detection and selection function (ANDSF) server, an enhanced packet data gateway (ePDG) and/or a mobility management entity (MME).

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0006] FIG. 1 illustrates atmospheric ducting under certain environmental conditions.

[0007] FIG. 2 illustrates remote interference in a wireless communication system without mitigation.

[0008] FIG. 3 illustrates a victim-only mitigation in accordance with one embodiment.

[0009] FIG. 4 illustrates an aggressor-only mitigation in accordance with one embodiment.

[0010] FIG. 5 illustrates victim and aggressor mitigation in accordance with one embodiment.

[0011] FIG. 6 illustrates a first example framework in accordance with one embodiment.

[0012] FIG. 7 illustrates a second example framework in accordance with one embodiment.

[0013] FIG. 8 illustrates a third example framework in accordance with one embodiment.

[0014] FIG. 9 illustrates a method in accordance with one embodiment.

[0015] FIG. 10 illustrates a method in accordance with one embodiment.

[0016] FIG. 11 illustrates a system in accordance with one embodiment.

[0017] FIG. 12 illustrates a device in accordance with one embodiment.

[0018] FIG. 13 illustrates an example interfaces in accordance with one embodiment.

[0019] FIG. 14 illustrates a control plane in accordance with one embodiment.

[0020] FIG. 15 illustrates a user plane in accordance with one embodiment.

[0021] FIG. 16 illustrates components in accordance with one embodiment.

[0022] FIG. 17 illustrates a system in accordance with one embodiment.

[0023] FIG. 18 illustrates components in accordance with one embodiment.

DETAILED DESCRIPTION

[0024] Remote interference may be observed in commercial time division long term evolution (TD-LTE) networks with macro deployment scenarios where a relatively large number of eNBs intermittently suffered from deteriorating Interference-over-Thermal (IoT). In some implementations, such interference may have values even higher than -105 decibel-milliwatts (dBm), which may severely impact the network coverage and connection success rate. It was identified that this kind of IoT degradation is caused by the downlink (DL) signal of a remote eNB (as far as 300 kilometers (km) away) due to atmospheric ducting under certain atmospheric conditions.

[0025] For example, FIG. 1 illustrates atmospheric ducting 100 when warm moist air is trapped between a first layer 102 and a second layer 104 of cold dry air. Under such conditions, a victim gNB 106 may experience interference from DL signals transmitted by one or more remote aggressor gNBs, such as first aggressor gNB 108 and second aggressor gNB 110 shown in FIG. 1. The DL signals from the 108 and/or the second aggressor gNB 110 may far exceed their normal transmission range (e.g., over ground or sea) by bouncing between the first layer 102 and the second layer 104 within the warm moist air. The DL transmissions from the first aggressor gNB 108 and/or the second aggressor gNB 110 may interfere with at least a portion of an uplink (UL) channel of the victim gNB 106. This phenomenon of atmospheric duct interference (ADI) may be referred to remote interference.

[0026] FIG. 2 illustrates remote interference 200 in a wireless communication system. In particular, FIG. 2 shows symbols 202 corresponding to a victim gNB (gNBl) with respect to symbols 204 corresponding to a remotely located aggressor gNB (gNB2). The symbols 202 of the victim gNB include DL symbols 206 and UL symbols 208 separated by a guard period (GP) (shown as GP 210). Similarly, the symbols 204 of the aggressor gNB include DL symbols 212 and UL symbols 214 separated by a GP 216. The GP 210 and the GP 216 do not include any DL or UL symbols.

[0027] As shown in FIG. 2, DL resources (time and frequency) of the aggressor gNB may coincide with the UL resources allocated by the victim gNB such that a portion of the DL symbols 212 of the aggressor gNB interferes with one or more symbols 218 of the UL symbols 208 of the victim gNB. While the victim gNB (gNBl) could also act as an aggressor to gNB2 (as shown by the dashed line of the DL symbols 206), to simplify the description, the example in FIG. 2 highlights gNB2 as the aggressor to gNB. Also, this example is without mitigation to reduce or eliminate the degradation caused by remote interference.

[0028] In certain embodiments discussed herein, remote interference management (RIM) may be used to alleviate the degradation suffered by the uplink channel. Different types of schemes that may be used to mitigate remote interference. Certain mitigation schemes may be categorized based on the domain of the action, such as: time domain, e.g., increasing the guard period (GP); frequency domain, e.g., schedule different frequency resources for DL and/or UL; power domain, e.g., reducing transmission power for DL; and spatial domain, e.g., changing downtilt angle for DL.

[0029] Moreover, the mitigation actions can be categorized, based on which gNB (e.g., victim or aggressor) is taking the action.

[0030] For example, FIG. 3 illustrates a victim-only mitigation 300, in accordance with one embodiment, wherein the victim gNB (gNBl) backs off UL. In the example shown in FIG. 3, the victim gNB reallocates the UL resources of a UL symbols 302 to avoid interference with the DL resources of the DL symbols 212 of the aggressor gNB (gNB2). For a victim-only mitigation scheme, the victim gNB may measure the remote interference and take interference mitigation actions on its own. No interaction between the victim gNB and the aggressor gNB may be needed. The interference measurement at the victim gNB may not need a dedicated reference signal.

[0031] As another mitigation example, FIG. 4 illustrates an aggressor-only mitigation 400, in accordance with one embodiment, wherein the aggressor gNB (gNB2) backs of DL. In the example shown in FIG. 4, the aggressor gNB reconfigures the DL resources of a DL symbols 402 so as to not interfere with the UL resources of the UL symbols 208. For an aggressor-only mitigation scheme, this type of action may require identification of the aggressor gNB. Thus, according to certain embodiments herein, such type of action may use a RIM-reference signal (RIM-RS), as discussed below.

[0032] As yet another mitigation example, FIG. 5 illustrates victim and aggressor mitigation 500, in accordance with one embodiment, wherein the aggressor gNB (gNB2) backs off DL and the victim gNB (gNBl) backs off UL. Thus, the aggressor gNB reconfigures the DL resources of a DL symbols 502 and the victim gNB reallocates the UL resources of a UL symbols 504 to avoid remote interference.

[0033] The mitigation schemes with aggressor action, such as those shown in FIG. 4 and FIG. 5, can be applied within a framework that automates the triggering of the transmission and monitoring of the RIM-RS when atmospheric ducting is detected, as well as the termination of the transmission and monitoring of the RIM-RS when atmospheric ducting disappears. [0034] FIG. 6 illustrates a first example framework 600 in accordance with one embodiment. The first example framework 600 is a general framework that does not include using RIM backhaul signaling. In step 0, a victim gNB 602 detects remote interference from an aggressor gNB 604. The victim gNB 602 may or may not know the identity of the aggressor gNB 604. In step 1 , in response to the remote interference, the victim gNB 602 starts reference signal (RS) monitoring and begins transmission of a first reference signal (RS1). The aggressor gNB 604 begins RS monitoring because, e.g., it is triggered by the operator or because it also suffers from remote interference. In step 2, the aggressor gNB 604 applies one or more remote interference scheme(s) and begins transmission of a second reference signal (RS-2). The victim gNB 602 continues to transmit RS-l as long as it detects remote interference or RS-2. In step 3, in response to the disappearance of RS-2, the victim gNB 602 stops RS-l transmission. In step 4, in response to detecting the disappearance of RS-l, the aggressor gNB 604 restores an original DL configuration and stops RS monitoring.

[0035] FIG. 7 illustrates a second example framework 700 in accordance with another embodiment. The second example framework 700 uses backhaul signaling for the aggressor gNB 604 to inform the victim gNB 602 on the reception of RS. In step 0, the victim gNB 602 detects remote interference from the 604. In step 1, in response to the remote interference, the victim gNB 602 begins RS transmission. The aggressor gNB 604 detects the RS transmission and performs RS monitoring of the RS from the victim gNB 602. In step 2, the aggressor gNB 604 applies one or more remote interference scheme(s) and informs the victim gNB 602, through a backhaul channel, of the reception of the RS. In step 3, in response to no longer detecting the RS from the victim gNB 602, the aggressor gNB 604 informs the victim gNB 602, through the backhaul channel, of the "disappearance" of the RS. The victim gNB 602 stops the RS transmission in response to receiving the backhaul message from the aggressor gNB 604 indicating the disappearance of the RS and therefore, the disappearance of the atmospheric duct. The aggressor gNB 604 may also restore an original DL configuration and stop RS monitoring.

[0036] FIG. 8 illustrates a third example framework 800 in accordance with another embodiment. The third example framework 800 uses backhaul signaling for the aggressor gNB 604 to inform the victim gNB 602 on the reception of RS and for the victim gNB 602 to send information to assist with RIM coordination. In step 0, the victim gNB 602 detects remote interference from the 604. In step 1, in response to the remote interference, the victim gNB 602 begins RS transmission. The aggressor gNB 604 detects the RS transmission from the victim gNB 602. In step 2, the aggressor gNB 604 informs the victim gNB 602, through a backhaul channel, of the reception of the RS. In step 3, the victim gNB 602 sends information to the aggressor gNB 604, through a backhaul channel, to assist with RIM coordination. In step 4, the aggressor gNB 604 uses the information to assist with RIM coordination to apply one or more remote interference scheme(s). In step 5, in response to no longer detecting the RS from the victim gNB 602, the aggressor gNB 604 informs the victim gNB 602, through the backhaul channel, of the "disappearance" of the RS. The victim gNB 602 stops the RS transmission in response to receiving the backhaul message from the aggressor gNB 604 indicating the disappearance of the RS and therefore, the disappearance of the atmospheric duct. The aggressor gNB 604 may also restore an original DL configuration and stop RS monitoring.

[0037] In certain embodiments, to enable more advanced RIM operations, backhaul signaling is used for coordination among gNBs on group formation and group operation and/or for coordination among aggressor gNBs on remote interference mitigation mechanisms.

[0038] In certain embodiments, backhaul message definitions assist with achieving the advanced RIM operations.

[0039] In one embodiment, a RIM notification message comprises a flag for detection and disappearance of RIM-RS, the number of UL symbols at the victim gNB that are experiencing interference, and configuration information about the sender gNB (e.g., numerology and DL/UL configuration). When a RIM notification message is sent by the victim gNB to the aggressor gNB to inform the recipient gNB that it is causing remote interference to the sender, the flag for detection and disappearance of RIM-RS may be set to DETECTED value. When a RIM notification message is sent by the aggressor gNB to the victim gNB to inform the recipient gNB that the RIM-RS is disappeared (i.e., RIM-RS is no longer detected), the flag for detection and disappearance of RIM-RS may be set to DISAPPEARED value.

[0040] By way of example of a RIM notification message, a backhaul message may include RIM information defined by:

RIMInformation : := SEQUENCE {

targetgNBSetID GNBSetID,

rIM-RSDetection ENUMERATED {rs-detected, rs-disappeared, ...},

} [0041] In the above example for RIMInformation, the GNBSetID comprises an identifier (ID) used to identify a group of gNBs which transmit the same RIM-RS. Further the rlM- RSDetection field corresponds to a flag to indicate detection (rs-detected) and disappearance (rs-disappeared) of the RIM-RS signal from a victim gNB. In certain embodiments, the

RIMInformation may be sent on a next generation application protocol (NGAP) interface wherein the gNBs communicate messages through an access and mobility management function (AMF). The messages communicated through the NGAP interface may include destination and target information for routing by the AMF. However, any other interface may be used that allows gNBs to communication with each other. For example, certain embodiments may use an Xn application protocol (XnAP) interface.

[0042] Other types of backhaul RIM messages may also be used. In one embodiment, for example, a RIM-Coordination Message Type 1 may include the following information: a list of victims detected by the (sender) gNB; a list of the received RIM-RS power of each detected victim; a list of the number of UL symbols suffering from interference at each victim; and configuration information about the sender gNB (e.g., numerology and DL/UL configuration).

[0043] In addition, or in another embodiment, a RIM-Coordination Message Type 2 may include the following information: a list of aggressors that notified by the (sender) gNB of detecting its RIM-RS; a list of the received RIM-RS power reported by each aggressor; a list of the number of UL symbols suffering from interference due to each aggressor; and configuration information about the sender gNB (e.g., numerology and DL/UL configuration).

[0044] In addition, or in another embodiment, a RIM-Coordination Message Type 3 may include the following information: a gNB group ID information; and a type of mitigation actions and configurations (e.g., time-domain, frequency-domain, spatial-domain, power domain and antenna downtilt). The gNB group ID information may be used to identify a group of gNBs which transmit the same RIM-RS.

[0045] FIG. 9 is a flowchart illustrating a method 900 for remote interference management (RIM) by a first gNB in a wireless communication system. In this example the first gNB corresponds to a victim gNB and a second gNB corresponds to an aggressor gNB. In block 902, the method 900 detects remote interference from the second gNB that degrades performance of an UL channel. In block 904, in response to the remote interference, the method 900 generates and transmits a RIM-RS. In block 906, the method 900 processes a first RIM notification message from the second gNB received through a backhaul channel. The first RIM notification message comprising a first RIM-RS detection flag and first configuration information corresponding to the second gNB. The first RIM-RS detection flag indicating that the second gNB detected the RIM-RS. In block 908, the method 900 processes a second RIM notification message from the second gNB received through the backhaul channel. The second RIM notification message comprising a second RIM-RS detection flag indicating that the RIM-RS disappeared from detection by the second gNB. In block 910, in response to the second RIM notification message, the method 900 stops transmission of the RIM-RS.

[0046] FIG. 10 is a flowchart of a method 1000 for remote interference management (RIM) by an aggressor gNB in a wireless communication system. In block 1002, the method 1000 detects a RIM reference signal (RIM-RS) from a victim gNB, the RIM-RS indicating that downlink (DL) transmissions from the aggressor gNB interfere with an uplink (UL) channel of the victim gNB. In block 1004, in response to detecting the RIM-RS, the method 1000 generates a first RIM notification message for communication to the victim gNB through a backhaul channel. The first RIM notification message comprising a first RIM-RS detection flag and first configuration information corresponding to the aggressor gNB. The first RIM-RS detection flag indicating that the aggressor gNB detected the RIM-RS. In block 1006, the method 1000 applies one or more remote interference mitigation schemes. In block 1008, the method 1000 monitors for disappearance of the RIM-RS. In block 1010, in response to detecting disappearance of the RIM-RS, the method 1000 generates a second RIM notification message for communication to the victim gNB through the backhaul channel, the second RIM notification message comprising a second RIM-RS detection flag indicating that the RIM-RS disappeared from detection by the aggressor gNB.

[0047] Example Systems and Apparatuses

[0048] FIG. 11 illustrates an architecture of a system 1100 of a network in accordance with some embodiments. The system 1100 is shown to include a UE 1102; a 5G access node or RAN node (shown as (R)AN node 1108); a User Plane Function (shown as UPF 1104); a Data Network (DN 1106), which may be, for example, operator services, Internet access or 3rd party services; and a 5G Core Network (5GC) (shown as CN 1110).

[0049] The CN 1110 may include an Authentication Server Function (AUSF 1114); a Core Access and Mobility Management Function (AMF 1112); a Session Management Function (SMF 1118); a Network Exposure Function (NEF 1116); a Policy Control Function (PCF 1122); a Network Function (NF) Repository Function (NRF 1120); a Unified Data Management (UDM 1124); and an Application Function (AF 1126). The CN 1110 may also include other elements that are not shown, such as a Structured Data Storage network function (SDSF), an

Unstructured Data Storage network function (UDSF), and the like.

[0050] The UPF 1104 may act as an anchor point for intra-RAT and inter-RAT mobility, an external PDU session point of interconnect to DN 1106, and a branching point to support multi-homed PDU session. The UPF 1104 may also perform packet routing and forwarding, packet inspection, enforce user plane part of policy rules, lawfully intercept packets (UP collection); traffic usage reporting, perform QoS handling for user plane (e.g. packet filtering, gating, UL/DL rate enforcement), perform Uplink Traffic verification (e.g., SDF to QoS flow mapping), transport level packet marking in the uplink and downlink, and downlink packet buffering and downlink data notification triggering. UPF 1104 may include an uplink classifier to support routing traffic flows to a data network. The DN 1106 may represent various network operator services, Internet access, or third party services.

[0051] The AUSF 1114 may store data for authentication of UE 1102 and handle

authentication related functionality. The AUSF 1114 may facilitate a common authentication framework for various access types.

[0052] The AMF 1112 may be responsible for registration management (e.g., for registering UE 1102, etc.), connection management, reachability management, mobility management, and lawful interception of AMF-related events, and access authentication and authorization. AMF 1112 may provide transport for SM messages for the SMF 1118, and act as a transparent proxy for routing SM messages. AMF 1112 may also provide transport for short message service (SMS) messages between UE 1102 and an SMS function (SMSF) (not shown by FIG.

11). AMF 1112 may act as Security Anchor Function (SEA), which may include interaction with the AUSF 1114 and the UE 1102, receipt of an intermediate key that was established as a result of the UE 1102 authentication process. Where USIM based authentication is used, the AMF 1112 may retrieve the security material from the AUSF 1114. AMF 1112 may also include a Security Context Management (SCM) function, which receives a key from the SEA that it uses to derive access-network specific keys. Furthermore, AMF 1112 may be a termination point of RAN CP interface (N2 reference point), a termination point of NAS (NI) signaling, and perform NAS ciphering and integrity protection.

[0053] AMF 1112 may also support NAS signaling with a UE 1102 over an N3 interworking -function (IWF) interface. The N3IWF may be used to provide access to untrusted entities. N3IWF may be a termination point for the N2 and N3 interfaces for control plane and user plane, respectively, and as such, may handle N2 signaling from SMF and AMF for PDU sessions and QoS, encapsulate/de-encapsulate packets for IPSec and N3 tunneling, mark N3 user-plane packets in the uplink, and enforce QoS corresponding to N3 packet marking taking into account QoS requirements associated to such marking received over N2. N3IWF may also relay uplink and downlink control-plane NAS (NI) signaling between the UE 1102 and AMF 1112, and relay uplink and downlink user-plane packets between the UE 1102 and UPF

1104. The N3IWF also provides mechanisms for IPsec tunnel establishment with the UE 1102.

[0054] The SMF 1118 may be responsible for session management (e.g., session

establishment, modify and release, including tunnel maintain between UPF and AN node); UE IP address allocation & management (including optional Authorization); Selection and control of UP function; Configures traffic steering at UPF to route traffic to proper destination;

termination of interfaces towards Policy control functions; control part of policy enforcement and QoS; lawful intercept (for SM events and interface to LI System); termination of SM parts of NAS messages; downlink Data Notification; initiator of AN specific SM information, sent via AMF over N2 to AN; determine SSC mode of a session. The SMF 1118 may include the following roaming functionality: handle local enforcement to apply QoS SLAs (VPLMN); charging data collection and charging interface (VPLMN); lawful intercept (in VPLMN for SM events and interface to LI System); support for interaction with external DN for transport of signaling for PDU session authorization/authentication by external DN.

[0055] The NEF 1116 may provide means for securely exposing the services and capabilities provided by 3 GPP network functions for third party, internal exposure/re-exposure, Application Functions (e.g., AF 1126), edge computing or fog computing systems,

etc. In such embodiments, the NEF 1116 may authenticate, authorize, and/or throttle the AFs. NEF 1116 may also translate information exchanged with the AF 1126 and information exchanged with internal network functions. For example, the NEF 1116 may translate between an AF-Service-Identifier and an internal 5GC information. NEF 1116 may also receive information from other network functions (NFs) based on exposed capabilities of other network functions. This information may be stored at the NEF 1116 as structured data, or at a data storage NF using a standardized interfaces. The stored information can then be re-exposed by the NEF 1116 to other NFs and AFs, and/or used for other purposes such as analytics. [0056] The NRF 1120 may support service discovery functions, receive NF Discovery Requests from NF instances, and provide the information of the discovered NF instances to the NF instances. NRF 1120 also maintains information of available NF instances and their supported services.

[0057] The PCF 1122 may provide policy rules to control plane function(s) to enforce them, and may also support unified policy framework to govern network behavior. The PCF 1122 may also implement a front end (FE) to access subscription information relevant for policy decisions in a UDR of UDM 1124.

[0058] The UDM 1124 may handle subscription-related information to support the network entities' handling of communication sessions, and may store subscription data of UE 1102. The UDM 1124 may include two parts, an application FE and a User Data Repository (UDR). The UDM may include a UDM FE, which is in charge of processing of credentials, location management, subscription management and so on. Several different front ends may serve the same user in different transactions. The UDM-FE accesses subscription information stored in the UDR and performs authentication credential processing; user identification handling; access authorization; registration/mobility management; and subscription management. The UDR may interact with PCF 1122 . UDM 1124 may also support SMS management, wherein an SMS-FE implements the similar application logic as discussed previously.

[0059] The AF 1126 may provide application influence on traffic routing, access to the Network Capability Exposure (NCE), and interact with the policy framework for policy control. The NCE may be a mechanism that allows the 5GC and AF 1126 to provide information to each other via NEF 1116, which may be used for edge computing

implementations. In such implementations, the network operator and third party services may be hosted close to the UE 1102 access point of attachment to achieve an efficient service delivery through the reduced end-to-end latency and load on the transport network. For edge computing implementations, the 5GC may select a UPF 1104 close to the UE 1102 and execute traffic steering from the UPF 1104 to DN 1106 via the N6 interface. This may be based on the UE subscription data, UE location, and information provided by the AF 1126. In this way, the AF 1126 may influence UPF (re)selection and traffic routing. Based on operator deployment, when AF 1126 is considered to be a trusted entity, the network operator may permit AF 1126 to interact directly with relevant NFs. [0060] As discussed previously, the CN 1110 may include an SMSF, which may be responsible for SMS subscription checking and verification, and relaying SM messages to/from the UE 1102 to/from other entities, such as an SMS -GMSC/IWMS C/SMS -router. The SMS may also interact with AMF 1112 and UDM 1124 for notification procedure that the UE 1102 is available for SMS transfer (e.g., set a UE not reachable flag, and notifying UDM 1124 when UE 1102 is available for SMS).

[0061] The system 1100 may include the following service-based interfaces: Namf:

Service-based interface exhibited by AMF; Nsmf: Service-based interface exhibited by SMF; Nnef: Service-based interface exhibited by NEF;

Npcf: Service-based interface exhibited by PCF; Nudm: Service-based interface

exhibited by UDM; Naf: Service-based interface exhibited by AF; Nnrf: Service-based interface exhibited by NRF; and Nausf: Service-based interface exhibited by AUSF.

[0062] The system 1100 may include the following reference points: Nl : Reference point between the UE and the AMF; N2: Reference point between the (R)AN and the AMF; N3: Reference point between the (R)AN and the UPF; N4: Reference point between the SMF and the UPF; and N6: Reference point between the UPF and a Data Network. There may be many more reference points and/or service-based interfaces between the NF services in the NFs, however, these interfaces and reference points have been omitted for clarity. For example, an NS reference point may be between the PCF and the AF; an N7 reference point may be between the PCF and the SMF; an Nl 1 reference point between the AMF and SMF; etc. In some embodiments, the CN 1110 may include an Nx interface, which is an inter-CN interface between the MME (e.g., MME(s) 1428) and the AMF 1112 in order to enable interworking between CN 1110 and CN 1606.

[0063] Although not shown by FIG. 11, the system 1100 may include multiple RAN nodes (such as (R)AN node 1108) wherein an Xn interface is defined between two or more (R)AN node 1108 (e.g., gNBs and the like) that connecting to 5GC 410, between a (R)AN node 1108 (e.g., gNB) connecting to CN 1110 and an eNB, and/or between two eNBs connecting to CN 1110

[0064] In some implementations, the Xn interface may include an Xn user plane (Xn-U) interface and an Xn control plane (Xn-C) interface. The Xn-U may provide non-guaranteed delivery of user plane PDUs and support/provide data forwarding and flow control

functionality. The Xn-C may provide management and error handling functionality, functionality to manage the Xn-C interface; mobility support for UE 1102 in a connected mode (e.g., CM-CONNECTED) including functionality to manage the UE mobility for connected mode between one or more (R)AN node 1108. The mobility support may include context transfer from an old (source) serving (R)AN node 1108 to new (target) serving (R)AN node 1108; and control of user plane tunnels between old (source) serving (R)AN node 1108 to new (target) serving (R)AN node 1108.

[0065] A protocol stack of the Xn-U may include a transport network layer built on Internet Protocol (IP) transport layer, and a GTP-U layer on top of a UDP and/or IP layer(s) to carry user plane PDUs. The Xn-C protocol stack may include an application layer signaling protocol (referred to as Xn Application Protocol (Xn-AP)) and a transport network layer that is built on an SCTP layer. The SCTP layer may be on top of an IP layer. The SCTP layer provides the guaranteed delivery of application layer messages. In the transport IP layer point-to-point transmission is used to deliver the signaling PDUs. In other implementations, the Xn-U protocol stack and/or the Xn-C protocol stack may be same or similar to the user plane and/or control plane protocol stack(s) shown and described herein.

[0066] FIG. 12 illustrates example components of a device 1200 in accordance with some embodiments. In some embodiments, the device 1200 may include application circuitry 1202, baseband circuitry 1204, Radio Frequency (RF) circuitry (shown as RF circuitry 1220), front- end module (FEM) circuitry (shown as FEM circuitry 1230), one or more antennas 1232, and power management circuitry (PMC) (shown as PMC 1234) coupled together at least as shown. The components of the illustrated device 1200 may be included in a UE or a RAN node. In some embodiments, the device 1200 may include fewer elements (e.g., a RAN node may not utilize application circuitry 1202, and instead include a processor/controller to process IP data received from an EPC). In some embodiments, the device 1200 may include additional elements such as, for example, memory/storage, display, camera, sensor, or input/output (I/O) interface. In other embodiments, the components described below may be included in more than one device (e.g., said circuitries may be separately included in more than one device for Cloud-RAN (C-RAN) implementations).

[0067] The application circuitry 1202 may include one or more application processors. For example, the application circuitry 1202 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with or may include memory/storage and may be configured to execute instructions stored in the memory/storage to enable various

applications or operating systems to run on the device 1200. In some embodiments, processors of application circuitry 1202 may process IP data packets received from an EPC.

[0068] The baseband circuitry 1204 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 1204 may include one or more baseband processors or control logic to process baseband signals received from a receive signal path of the RF circuitry 1220 and to generate baseband signals for a transmit signal path of the RF circuitry 1220. The baseband circuitry 1204 may interface with the application circuitry 1202 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 1220. For example, in some embodiments, the baseband circuitry 1204 may include a third generation (3G) baseband processor (3G baseband processor 1206), a fourth generation (4G) baseband processor (4G baseband processor 1208), a fifth generation (5G) baseband processor (5G baseband processor 1210), or other baseband processor(s) 1212 for other existing generations, generations in development or to be developed in the future (e.g., second generation (2G), sixth generation (6G), etc.). The baseband circuitry 1204 (e.g., one or more of baseband processors) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 1220. In other embodiments, some or all of the functionality of the illustrated baseband processors may be included in modules stored in the memory 1218 and executed via a Central Processing Unit (CPU 1214). The radio control functions may include, but are not limited to, signal

modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry 1204 may include Fast-Fourier Transform (FFT), precoding, or constellation mapping/demapping

functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry 1204 may include convolution, tail-biting convolution, turbo, Viterbi, or Low Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

[0069] In some embodiments, the baseband circuitry 1204 may include a digital signal processor (DSP), such as one or more audio DSP(s) 1216. The one or more audio DSP(s) 1216 may include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry 1204 and the application circuitry 1202 may be implemented together such as, for example, on a system on a chip (SOC).

[0070] In some embodiments, the baseband circuitry 1204 may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 1204 may support communication with an evolved universal terrestrial radio access network (EUTRAN) or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), or a wireless personal area network (WPAN). Embodiments in which the baseband circuitry 1204 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry.

[0071] The RF circuitry 1220 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 1220 may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. The RF circuitry 1220 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 1230 and provide baseband signals to the baseband circuitry 1204. The RF circuitry 1220 may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband circuitry 1204 and provide RF output signals to the FEM circuitry 1230 for transmission.

[0072] In some embodiments, the receive signal path of the RF circuitry 1220 may include mixer circuitry 1222, amplifier circuitry 1224 and filter circuitry 1226. In some embodiments, the transmit signal path of the RF circuitry 1220 may include filter circuitry 1226 and mixer circuitry 1222. The RF circuitry 1220 may also include synthesizer circuitry 1228 for synthesizing a frequency for use by the mixer circuitry 1222 of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 1222 of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry 1230 based on the synthesized frequency provided by synthesizer circuitry 1228. The amplifier circuitry 1224 may be configured to amplify the down- converted signals and the filter circuitry 1226 may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry 1204 for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, the mixer circuitry 1222 of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

[0073] In some embodiments, the mixer circuitry 1222 of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 1228 to generate RF output signals for the FEM circuitry 1230. The baseband signals may be provided by the baseband circuitry 1204 and may be filtered by the filter circuitry 1226.

[0074] In some embodiments, the mixer circuitry 1222 of the receive signal path and the mixer circuitry 1222 of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and upconversion, respectively. In some embodiments, the mixer circuitry 1222 of the receive signal path and the mixer circuitry 1222 of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 1222 of the receive signal path and the mixer circuitry 1222 may be arranged for direct downconversion and direct upconversion, respectively. In some embodiments, the mixer circuitry 1222 of the receive signal path and the mixer circuitry 1222 of the transmit signal path may be configured for super-heterodyne operation.

[0075] In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 1220 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 1204 may include a digital baseband interface to communicate with the RF circuitry 1220.

[0076] In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

[0077] In some embodiments, the synthesizer circuitry 1228 may be a fractional-N synthesizer or a fractional N/N+l synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 1228 may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[0078] The synthesizer circuitry 1228 may be configured to synthesize an output frequency for use by the mixer circuitry 1222 of the RF circuitry 1220 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 1228 may be a fractional N/N+l synthesizer.

[0079] In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 1204 or the application circuitry 1202 (such as an applications processor) depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the application circuitry 1202.

[0080] Synthesizer circuitry 1228 of the RF circuitry 1220 may include a divider, a delay- locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DP A). In some embodiments, the DMD may be configured to divide the input signal by either N or N+l (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

[0081] In some embodiments, the synthesizer circuitry 1228 may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fLO). In some embodiments, the RF circuitry 1220 may include an IQ/polar converter.

[0082] The FEM circuitry 1230 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 1232, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 1220 for further processing. The FEM circuitry 1230 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 1220 for transmission by one or more of the one or more antennas 1232. In various embodiments, the amplification through the transmit or receive signal paths may be done solely in the RF circuitry 1220, solely in the FEM circuitry 1230, or in both the RF circuitry 1220 and the FEM circuitry 1230.

[0083] In some embodiments, the FEM circuitry 1230 may include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry 1230 may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry 1230 may include an LNA to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 1220). The transmit signal path of the FEM circuitry 1230 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by the RF circuitry 1220), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 1232).

[0084] In some embodiments, the PMC 1234 may manage power provided to the baseband circuitry 1204. In particular, the PMC 1234 may control power-source selection, voltage scaling, battery charging, or DC-to-DC conversion. The PMC 1234 may often be included when the device 1200 is capable of being powered by a battery, for example, when the device 1200 is included in a EGE. The PMC 1234 may increase the power conversion efficiency while providing desirable implementation size and heat dissipation characteristics.

[0085] FIG. 12 shows the PMC 1234 coupled only with the baseband circuitry 1204. However, in other embodiments, the PMC 1234 may be additionally or alternatively coupled with, and perform similar power management operations for, other components such as, but not limited to, the application circuitry 1202, the RF circuitry 1220, or the FEM circuitry 1230.

[0086] In some embodiments, the PMC 1234 may control, or otherwise be part of, various power saving mechanisms of the device 1200. For example, if the device 1200 is in an

RRC Connected state, where it is still connected to the RAN node as it expects to receive traffic shortly, then it may enter a state known as Discontinuous Reception Mode (DRX) after a period of inactivity. During this state, the device 1200 may power down for brief intervals of time and thus save power.

[0087] If there is no data traffic activity for an extended period of time, then the device 1200 may transition off to an RRC Idle state, where it disconnects from the network and does not perform operations such as channel quality feedback, handover, etc. The device 1200 goes into a very low power state and it performs paging where again it periodically wakes up to listen to the network and then powers down again. The device 1200 may not receive data in this state, and in order to receive data, it transitions back to an RRC Connected state.

[0088] An additional power saving mode may allow a device to be unavailable to the network for periods longer than a paging interval (ranging from seconds to a few hours). During this time, the device is totally unreachable to the network and may power down completely. Any data sent during this time incurs a large delay and it is assumed the delay is acceptable.

[0089] Processors of the application circuitry 1202 and processors of the baseband circuitry 1204 may be used to execute elements of one or more instances of a protocol stack. For example, processors of the baseband circuitry 1204, alone or in combination, may be used to execute Layer 3, Layer 2, or Layer 1 functionality, while processors of the application circuitry 1202 may utilize data (e.g., packet data) received from these layers and further execute Layer 4 functionality (e.g., transmission communication protocol (TCP) and user datagram protocol (UDP) layers). As referred to herein, Layer 3 may comprise a radio resource control (RRC) layer, described in further detail below. As referred to herein, Layer 2 may comprise a medium access control (MAC) layer, a radio link control (RLC) layer, and a packet data convergence protocol (PDCP) layer, described in further detail below. As referred to herein, Layer 1 may comprise a physical (PHY) layer of a UE/RAN node, described in further detail below.

[0090] FIG. 13 illustrates example interfaces 1300 of baseband circuitry in accordance with some embodiments. As discussed above, the baseband circuitry 1204 of FIG. 12 may comprise 3G baseband processor 1206, 4G baseband processor 1208, 5G baseband processor 1210, other baseband processor(s) 1212, CPU 1214, and a memory 1218 utilized by said processors. As illustrated, each of the processors may include a respective memory interface 1302 to send/receive data to/from the memory 1218.

[0091] The baseband circuitry 1204 may further include one or more interfaces to

communicatively couple to other circuitries/devices, such as a memory interface 1304 (e.g., an interface to send/receive data to/from memory external to the baseband circuitry 1204), an application circuitry interface 1306 (e.g., an interface to send/receive data to/from the application circuitry 1202 of FIG. 12), an RF circuitry interface 1308 (e.g., an interface to send/receive data to/from RF circuitry 1220 of FIG. 12), a wireless hardware connectivity interface 1310 (e.g., an interface to send/receive data to/from Near Field Communication (NFC) components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components), and a power management interface 1312 (e.g., an interface to send/receive power or control signals to/from the PMC 1234.

[0092] FIG. 14 is an illustration of a control plane protocol stack in accordance with some embodiments. In this embodiment, a control plane 1400 is shown as a communications protocol stack between the UE 1402, the RAN 1408, and the MME(s) 1428.

[0093] A PHY layer 1404 may transmit or receive information used by the MAC layer 1406 over one or more air interfaces. The PHY layer 1404 may further perform link adaptation or adaptive modulation and coding (AMC), power control, cell search (e.g., for initial

synchronization and handover purposes), and other measurements used by higher layers, such as an RRC layer 1414. The PHY layer 1404 may still further perform error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, modulation/demodulation of physical channels, interleaving, rate matching, mapping onto physical channels, and Multiple Input Multiple Output (MIMO) antenna processing.

[0094] The MAC layer 1406 may perform mapping between logical channels and transport channels, multiplexing of MAC service data units (SDUs) from one or more logical channels onto transport blocks (TB) to be delivered to PHY via transport channels, de-multiplexing MAC SDUs to one or more logical channels from transport blocks (TB) delivered from the PHY via transport channels, multiplexing MAC SDUs onto TBs, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), and logical channel prioritization.

[0095] An RFC layer 1410 may operate in a plurality of modes of operation, including:

Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). The RFC layer 1410 may execute transfer of upper layer protocol data units (PDUs), error correction through automatic repeat request (ARQ) for AM data transfers, and concatenation, segmentation and reassembly of RFC SDUs for UM and AM data transfers. The RFC layer 1410 may also execute re-segmentation of RFC data PDUs for AM data transfers, reorder RFC data PDUs for UM and AM data transfers, detect duplicate data for UM and AM data transfers, discard RFC SDUs for UM and AM data transfers, detect protocol errors for AM data transfers, and perform RFC re-establishment.

[0096] A PDCP layer 1412 may execute header compression and decompression of IP data, maintain PDCP Sequence Numbers (SNs), perform in-sequence delivery of upper layer PDUs at re-establishment of lower layers, eliminate duplicates of lower layer SDUs at re-establishment of lower layers for radio bearers mapped on RLC AM, cipher and decipher control plane data, perform integrity protection and integrity verification of control plane data, control timer-based discard of data, and perform security operations (e.g., ciphering, deciphering, integrity protection, integrity verification, etc.).

[0097] The main services and functions of the RRC layer 1414 may include broadcast of system information (e.g., included in Master Information Blocks (MIBs) or System Information Blocks (SIBs) related to the non-access stratum (NAS)), broadcast of system information related to the access stratum (AS), paging, establishment, maintenance and release of an RRC connection between the UE and E-UTRAN (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), establishment, configuration, maintenance and release of point-to-point radio bearers, security functions including key management, inter radio access technology (RAT) mobility, and measurement configuration for EGE measurement reporting. Said MIBs and SIBs may comprise one or more information elements (IEs), which may each comprise individual data fields or data structures.

[0098] The EGE 1402 and the RAN 1408 may utilize a Uu interface (e.g., an LTE-Uu interface) to exchange control plane data via a protocol stack comprising the PHY layer 1404, the MAC layer 1406, the RLC layer 1410, the PDCP layer 1412, and the RRC layer 1414.

[0099] In the embodiment shown, the non-access stratum (NAS) protocols (NAS protocols 1416) form the highest stratum of the control plane between the EGE 1402 and the MME(s)

1428. The NAS protocols 1416 support the mobility of the UE 1402 and the session

management procedures to establish and maintain IP connectivity between the UE 1402 and the P-GW 1508.

[0100] The Sl Application Protocol (Sl-AP) layer (Sl-AP layer 1426) may support the functions of the Sl interface and comprise Elementary Procedures (EPs). An EP is a unit of interaction between the RAN 1408 and the CN 1606. The Sl-AP layer services may comprise two groups: UE-associated services and non ETE-associated services. These services perform functions including, but not limited to: E-ETTRAN Radio Access Bearer (E-RAB) management, EGE capability indication, mobility, NAS signaling transport, RAN Information Management (RIM), and configuration transfer.

[0101] The Stream Control Transmission Protocol (SCTP) layer (alternatively referred to as the stream control transmission protocol/internet protocol (SCTP/IP) layer) (SCTP layer 1424) may ensure reliable delivery of signaling messages between the RAN 1408 and the MME(s) 1428 based, in part, on the IP protocol, supported by an IP layer 1422. An L2 layer 1420 and an Ll layer 1418 may refer to communication links (e.g., wired or wireless) used by the RAN node and the MME to exchange information.

[0102] The RAN 1408 and the MME(s) 1428 may utilize an Sl-MME interface to exchange control plane data via a protocol stack comprising the Ll layer 1418, the L2 layer 1420, the IP layer 1422, the SCTP layer 1424, and the Sl-AP layer 1426.

[0103] FIG. 15 is an illustration of a user plane protocol stack in accordance with some embodiments. In this embodiment, a user plane 1500 is shown as a communications protocol stack between the UE 1402, the RAN 1408, the S-GW 1506, and the P-GW 1508. The user plane 1500 may utilize at least some of the same protocol layers as the control plane 1400. For example, the UE 1402 and the RAN 1408 may utilize a Uu interface (e.g., an LTE-Uu interface) to exchange user plane data via a protocol stack comprising the PHY layer 1404, the MAC layer 1406, the RLC layer 1410, the PDCP layer 1412.

[0104] The General Packet Radio Service (GPRS) Tunneling Protocol for the user plane (GTP-U) layer (GTP-U layer 1504) may be used for carrying user data within the GPRS core network and between the radio access network and the core network. The user data transported can be packets in any of IPv4, IPv6, or PPP formats, for example. The UDP and IP security (UDP/IP) layer (UDP/IP layer 1502) may provide checksums for data integrity, port numbers for addressing different functions at the source and destination, and encryption and

authentication on the selected data flows. The RAN 1408 and the S-GW 1506 may utilize an S 1 -U interface to exchange user plane data via a protocol stack comprising the Ll layer 1418, the L2 layer 1420, the UDP/IP layer 1502, and the GTP-U layer 1504. The S-GW 1506 and the P-GW 1508 may utilize an S5/S8a interface to exchange user plane data via a protocol stack comprising the Ll layer 1418, the L2 layer 1420, the UDP/IP layer 1502, and the GTP-U layer 1504. As discussed above with respect to FIG. 14, NAS protocols support the mobility of the UE 1402 and the session management procedures to establish and maintain IP connectivity between the UE 1402 and the P-GW 1508.

[0105] FIG. 16 illustrates components 1600 of a core network in accordance with some embodiments. The components of the CN 1606 may be implemented in one physical node or separate physical nodes including components to read and execute instructions from a machine- readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium). In some embodiments, Network Functions Virtualization (NFV) is utilized to virtualize any or all of the above described network node functions via executable instructions stored in one or more computer readable storage mediums (described in further detail below). A logical instantiation of the CN 1606 may be referred to as a network slice 1602 (e.g., the network slice 1602 is shown to include the HSS 1608, the MME(s) 1428, and the S-GW 1506). A logical instantiation of a portion of the CN 1606 may be referred to as a network sub slice 1604 (e.g., the network sub-slice 1604 is shown to include the P-GW 1508 and the PCRF 1610).

[0106] NFV architectures and infrastructures may be used to virtualize one or more network functions, alternatively performed by proprietary hardware, onto physical resources comprising a combination of industry-standard server hardware, storage hardware, or switches. In other words, NFV systems can be used to execute virtual or reconfigurable implementations of one or more EPC components/functions.

[0107] FIG. 17 is a block diagram illustrating components, according to some example embodiments, of a system 1700 to support NFV. The system 1700 is illustrated as including a virtualized infrastructure manager (shown as VIM 1702), a network function virtualization infrastructure (shown as NFVI 1704), a VNF manager (shown as VNFM 1706), virtualized network functions (shown as VNF 1708), an element manager (shown as EM 1710), an NFV Orchestrator (shown as NFVO 1712), and a network manager (shown as NM 1714).

[0108] The VIM 1702 manages the resources of the NFVI 1704. The NFVI 1704 can include physical or virtual resources and applications (including hypervisors) used to execute the system 1700. The VIM 1702 may manage the life cycle of virtual resources with the NFVI 1704 (e.g., creation, maintenance, and tear down of virtual machines (VMs) associated with one or more physical resources), track VM instances, track performance, fault and security of VM instances and associated physical resources, and expose VM instances and associated physical resources to other management systems.

[0109] The VNFM 1706 may manage the VNF 1708. The VNF 1708 may be used to execute EPC components/functions. The VNFM 1706 may manage the life cycle of the VNF 1708 and track performance, fault and security of the virtual aspects of VNF 1708. The EM 1710 may track the performance, fault and security of the functional aspects of VNF 1708. The tracking data from the VNFM 1706 and the EM 1710 may comprise, for example, performance measurement (PM) data used by the VIM 1702 or the NFVI 1704. Both the VNFM 1706 and the EM 1710 can scale up/down the quantity of VNFs of the system 1700. [0110] The NFVO 1712 may coordinate, authorize, release and engage resources of the NFVI 1704 in order to provide the requested service (e.g., to execute an EPC function, component, or slice). The NM 1714 may provide a package of end-user functions with the responsibility for the management of a network, which may include network elements with VNFs, non-virtualized network functions, or both (management of the VNFs may occur via the EM 1710).

[0111] FIG. 18 is a block diagram illustrating components 1800, according to some example embodiments, able to read instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and perform any one or more of the methodologies discussed herein. Specifically, FIG. 18 shows a diagrammatic representation of hardware resources 1802 including one or more processors 1812 (or processor cores), one or more memory/storage devices 1818, and one or more communication resources 1820, each of which may be communicatively coupled via a bus 1822. For embodiments where node virtualization (e.g., NFV) is utilized, a hypervisor 1804 may be executed to provide an execution environment for one or more network slices/sub-slices to utilize the hardware resources 1802.

[0112] The processors 1812 (e.g., a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a complex instruction set computing (CISC) processor, a graphics processing unit (GPU), a digital signal processor (DSP) such as a baseband processor, an application specific integrated circuit (ASIC), a radio-frequency integrated circuit (RFIC), another processor, or any suitable combination thereof) may include, for example, a processor 1814 and a processor 1816.

[0113] The memory /storage devices 1818 may include main memory, disk storage, or any suitable combination thereof. The memory/storage devices 1818 may include, but are not limited to any type of volatile or non-volatile memory such as dynamic random access memory (DRAM), static random-access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), Flash memory, solid-state storage, etc.

[0114] The communication resources 1820 may include interconnection or network interface components or other suitable devices to communicate with one or more peripheral devices 1806 or one or more databases 1808 via a network 1810. For example, the communication resources 1820 may include wired communication components (e.g., for coupling via a Universal Serial Bus (USB)), cellular communication components, NFC components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components.

[0115] Instructions 1824 may comprise software, a program, an application, an applet, an app, or other executable code for causing at least any of the processors 1812 to perform any one or more of the methodologies discussed herein. The instructions 1824 may reside, completely or partially, within at least one of the processors 1812 (e.g., within the processor’s cache memory), the memory /storage devices 1818, or any suitable combination thereof. Furthermore, any portion of the instructions 1824 may be transferred to the hardware resources 1802 from any combination of the peripheral devices 1806 or the databases 1808. Accordingly, the memory of the processors 1812, the memory/storage devices 1818, the peripheral devices 1806, and the databases 1808 are examples of computer-readable and machine-readable media.

[0116] For one or more embodiments, at least one of the components set forth in one or more of the preceding figures may be configured to perform one or more operations, techniques, processes, and/or methods as set forth in the Example Section below. For example, the baseband circuitry as described above in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth below. For another example, circuitry associated with a UE, base station, network element, etc. as described above in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth below in the example section.

[0117] Example Section

[0118] The following examples pertain to further embodiments.

[0119] Example 1 is an apparatus for remote interference management (RIM) by a first next generation Node-B (gNB) in a wireless communication system. The apparatus includes a memory interface and a processor. The memory interface to send or receive, to or from a memory device, data corresponding to RIM notification messages. The processor to: detect remote interference from a second gNB that degrades performance of an uplink (UL) channel; in response to the remote interference, generate a RIM reference signal (RIM-RS); process a first RIM notification message from the second gNB received through a backhaul channel, the first RIM notification message comprising a first RIM-RS detection flag and first configuration information corresponding to the second gNB, the first RIM-RS detection flag indicating that the second gNB detected the RIM-RS; process a second RIM notification message from the second gNB received through the backhaul channel, the second RIM notification message comprising a second RIM-RS detection flag indicating that the RIM-RS disappeared from detection by the second gNB; and in response to the second RIM notification message, stop transmission of the RIM-RS.

[0120] Example 2 is the apparatus of Example 1, wherein the first configuration information comprises one or more of a numerology of the second gNB, a UL configuration of the second gNB, and a downlink (DL) configuration of the second gNB.

[0121] Example 3 is the apparatus of Example 1, wherein the first RIM notification message further comprises one or more of: a list of victim gNBs, include the first gNB, detected by the second gNB; a list of received RIM-RS power of the respective victim gNBs measured by the second gNB; and a list of a number of UL symbols interfered with at the respective victim gNBs.

[0122] Example 4 is the apparatus of Example 1, wherein the processor is further configured to, in response to the first RIM notification message and before the second RIM notification message is received through the backhaul channel, generate a RIM coordination message to send to the second gNB through the backhaul channel to assist with RIM coordination.

[0123] Example 5 is the apparatus of Example 4, wherein the RIM coordination message comprises one or more of: a list of aggressor gNBs, include the second gNB, that have indicated detection of the RIM-RS; a list of received RIM-RS power reported by the aggressor gNBs; a list of a number of UL symbols that the aggressor gNBs interfered with; and second

configuration information corresponding to the first gNB.

[0124] Example 6 is the apparatus of Example 5, wherein the second configuration

information comprises one or more of a numerology of the first gNB, an UL configuration of the first gNB, and a downlink (DL) configuration of the first gNB.

[0125] Example 7 is the apparatus of Example 1, wherein the first configuration information comprises a group identifier (ID) associated with the second gNB.

[0126] Example 8 is the apparatus of Example 7, wherein the first RIM notification message further comprises mitigation information indicate a type of mitigation action by the second gNB and corresponding mitigation configurations.

[0127] Example 9 is the apparatus of Example 8, wherein the type of mitigation action is selected from a group comprising time domain mitigation, frequency domain mitigation, power domain mitigation, and spatial domain mitigation. [0128] Example 10 is a method for remote interference management (RIM) by an aggressor next generation Node-B (gNB) in a wireless communication system. The method includes: detecting a RIM reference signal (RIM-RS) from a victim gNB, the RIM-RS indicating that downlink (DL) transmissions from the aggressor gNB interfere with an uplink (UL) channel of the victim gNB; in response to detecting the RIM-RS, generating a first RIM notification message for communication to the victim gNB through a backhaul channel, the first RIM notification message comprising a first RIM-RS detection flag and first configuration information corresponding to the aggressor gNB, the first RIM-RS detection flag indicating that the aggressor gNB detected the RIM-RS; applying one or more remote interference mitigation schemes; monitoring for disappearance of the RIM-RS; and in response to detecting

disappearance of the RIM-RS, generating a second RIM notification message for

communication to the victim gNB through the backhaul channel, the second RIM notification message comprising a second RIM-RS detection flag indicating that the RIM-RS disappeared from detection by the aggressor gNB.

[0129] Example 11 is the method of Example 10, wherein the first configuration information comprises one or more of a numerology of the aggressor gNB, a UL configuration of the aggressor gNB, and a downlink (DL) configuration of the aggressor gNB.

[0130] Example 12 is the method of Example 10, further comprising: measuring a received power of the RIM-RS; and reporting the received power of the RIM-RS to the victim gNB in the first RIM notification message.

[0131] Example 13 is the method of Example 10, wherein the first RIM notification message further comprises one or more of: a list of victim gNBs detected by the aggressor gNB; a list of received RIM-RS power of the respective victim gNBs measured by the aggressor gNB; and a list of a number of UL symbols interfered with at the respective victim gNBs.

[0132] Example 14 is the method of Example 10, further comprising, after generating the first RIM notification message and before generating the second RIM notification message, processing a RIM coordination message received from the victim gNB through the backhaul channel to assist with RIM coordination.

[0133] Example 15 is the method of Example 14, wherein the RIM coordination message comprises one or more of: a list of aggressor gNBs that have indicated detection of the RIM- RS; a list of received RIM-RS power reported by the aggressor gNBs; a list of a number of UL symbols that the aggressor gNBs interfered with; and second configuration information corresponding to the victim gNB.

[0134] Example 16 is the method of Example 15, wherein the second configuration

information comprises one or more of a numerology of the victim gNB, an UL configuration of the victim gNB, and a downlink (DL) configuration of the victim gNB.

[0135] Example 17 is the method of Example 10, wherein the first configuration information comprises a group identifier (ID) associated with the aggressor gNB.

[0136] Example 18 is the method of Example 10, wherein the group ID comprises a gNB set ID used to identify a group of gNBs which transmit the same RIM-RS.

[0137] Example 19 is the method of Example 17, wherein the first RIM notification message further comprises mitigation information indicating a type of mitigation action by the aggressor gNB and corresponding mitigation configurations.

[0138] Example 20 is the method of Example 18, wherein the type of mitigation action is selected from a group comprising time domain mitigation, frequency domain mitigation, power domain mitigation, and spatial domain mitigation.

[0139] Example 21 is the method of Example 18, wherein the backhaul channel comprises an interface configured to provide communication between gNBs, the interface selected from a group comprising an Xn interface and a next generation application protocol (NGAP) interface.

[0140] Example 22 is the method of Example 21 , wherein the interface comprises the NGAP interface, and wherein the first RIM notification message and the second RIM notification message include destination and target information for routing by an access and mobility management function (AMF) using the NGAP interface.

[0141] Any of the above described examples may be combined with any other example (or combination of examples), unless explicitly stated otherwise. The foregoing description of one or more implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of embodiments to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of various embodiments.

[0142] Embodiments and implementations of the systems and methods described herein may include various operations, which may be embodied in machine-executable instructions to be executed by a computer system. A computer system may include one or more general-purpose or special-purpose computers (or other electronic devices). The computer system may include hardware components that include specific logic for performing the operations or may include a combination of hardware, software, and/or firmware.

[0143] It should be recognized that the systems described herein include descriptions of specific embodiments. These embodiments can be combined into single systems, partially combined into other systems, split into multiple systems or divided or combined in other ways. In addition, it is contemplated that parameters/attributes/aspects/etc. of one embodiment can be used in another embodiment. The parameters/attributes/aspects/etc. are merely described in one or more embodiments for clarity, and it is recognized that the parameters/attributes/aspects/etc. can be combined with or substituted for parameters/attributes/etc. of another embodiment unless specifically disclaimed herein.

[0144] Although the foregoing has been described in some detail for purposes of clarity, it will be apparent that certain changes and modifications may be made without departing from the principles thereof. It should be noted that there are many alternative ways of implementing both the processes and apparatuses described herein. Accordingly, the present embodiments are to be considered illustrative and not restrictive, and the description is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.

Claims

1. An apparatus for remote interference management (RIM) by a first next generation Node-B (gNB) in a wireless communication system, the apparatus comprising:

a memory interface to send or receive, to or from a memory device, data corresponding to RIM notification messages; and

a processor to:

detect remote interference from a second gNB that degrades performance of an uplink (UL) channel;

in response to the remote interference, generate a RIM reference signal (RIM-

RS);

process a first RIM notification message from the second gNB received through a backhaul channel, the first RIM notification message comprising a first RIM-RS detection flag and first configuration information corresponding to the second gNB, the first RIM-RS detection flag indicating that the second gNB detected the RIM-RS;

process a second RIM notification message from the second gNB received through the backhaul channel, the second RIM notification message comprising a second RIM-RS detection flag indicating that the RIM-RS disappeared from detection by the second gNB; and

in response to the second RIM notification message, stop transmission of the RIM-RS.

2. The apparatus of claim 1, wherein the first configuration information comprises one or more of a numerology of the second gNB, a UL configuration of the second gNB, and a downlink (DL) configuration of the second gNB.

3. The apparatus of claim 1, wherein the first RIM notification message further comprises one or more of:

a list of victim gNBs, include the first gNB, detected by the second gNB;

a list of received RIM-RS power of the respective victim gNBs measured by the second gNB; and

a list of a number of UL symbols interfered with at the respective victim gNBs.

4. The apparatus of claim 1 , wherein the processor is further configured to, in response to the first RIM notification message and before the second RIM notification message is received through the backhaul channel, generate a RIM coordination message to send to the second gNB through the backhaul channel to assist with RIM coordination.

5. The apparatus of claim 4, wherein the RIM coordination message comprises one or more of: a list of aggressor gNBs, include the second gNB, that have indicated detection of the RIM-RS;

a list of received RIM-RS power reported by the aggressor gNBs;

a list of a number of UL symbols that the aggressor gNBs interfered with; and second configuration information corresponding to the first gNB.

6. The apparatus of claim 5, wherein the second configuration information comprises one or more of a numerology of the first gNB, an UL configuration of the first gNB, and a downlink (DL) configuration of the first gNB.

7. The apparatus of claim 1, wherein the first configuration information comprises a group identifier (ID) associated with the second gNB.

8. The apparatus of claim 7, wherein the first RIM notification message further comprises mitigation information indicate a type of mitigation action by the second gNB and

corresponding mitigation configurations.

9. The apparatus of claim 8, wherein the type of mitigation action is selected from a group comprising time domain mitigation, frequency domain mitigation, power domain mitigation, and spatial domain mitigation.

10. A method for remote interference management (RIM) by an aggressor next generation Node-B (gNB) in a wireless communication system, the method comprising:

detecting a RIM reference signal (RIM-RS) from a victim gNB, the RIM-RS indicating that downlink (DL) transmissions from the aggressor gNB interfere with an uplink (UL) channel of the victim gNB;

in response to detecting the RIM-RS, generating a first RIM notification message for communication to the victim gNB through a backhaul channel, the first RIM notification message comprising a first RIM-RS detection flag and first configuration information corresponding to the aggressor gNB, the first RIM-RS detection flag indicating that the aggressor gNB detected the RIM-RS;

applying one or more remote interference mitigation schemes;

monitoring for disappearance of the RIM-RS; and

in response to detecting disappearance of the RIM-RS, generating a second RIM notification message for communication to the victim gNB through the backhaul channel, the second RIM notification message comprising a second RIM-RS detection flag indicating that the RIM-RS disappeared from detection by the aggressor gNB.

11. The method of claim 10, wherein the first configuration information comprises one or more of a numerology of the aggressor gNB, a UL configuration of the aggressor gNB, and a downlink (DL) configuration of the aggressor gNB.

12. The method of claim 10, further comprising:

measuring a received power of the RIM-RS; and

reporting the received power of the RIM-RS to the victim gNB in the first RIM notification message.

13. The method of claim 10, wherein the first RIM notification message further comprises one or more of:

a list of victim gNBs detected by the aggressor gNB;

a list of received RIM-RS power of the respective victim gNBs measured by the aggressor gNB; and

a list of a number of UL symbols interfered with at the respective victim gNBs.

14. The method of claim 10, further comprising, after generating the first RIM notification message and before generating the second RIM notification message, processing a RIM coordination message received from the victim gNB through the backhaul channel to assist with RIM coordination.

15. The method of claim 14, wherein the RIM coordination message comprises one or more of: a list of aggressor gNBs that have indicated detection of the RIM-RS;

a list of received RIM-RS power reported by the aggressor gNBs;

a list of a number of UL symbols that the aggressor gNBs interfered with; and second configuration information corresponding to the victim gNB.

16. The method of claim 15, wherein the second configuration information comprises one or more of a numerology of the victim gNB, an UL configuration of the victim gNB, and a downlink (DL) configuration of the victim gNB.

17. The method of claim 10, wherein the first configuration information comprises a group identifier (ID) associated with the aggressor gNB.

18. The method of claim 10, wherein the group ID comprises a gNB set ID used to identify a group of gNBs which transmit the same RIM-RS.

19. The method of claim 17, wherein the first RIM notification message further comprises mitigation information indicating a type of mitigation action by the aggressor gNB and corresponding mitigation configurations.

20. The method of claim 18, wherein the type of mitigation action is selected from a group comprising time domain mitigation, frequency domain mitigation, power domain mitigation, and spatial domain mitigation.

21. The method of claim 18, wherein the backhaul channel comprises an interface configured to provide communication between gNBs, the interface selected from a group comprising an Xn interface and a next generation application protocol (NGAP) interface.

22. The method of claim 21, wherein the interface comprises the NGAP interface, and wherein the first RIM notification message and the second RIM notification message include destination and target information for routing by an access and mobility management function (AMF) using the NGAP interface.