Element selection for nodes

Abstract

Methods, systems, and devices are described for wireless communication. A first node of a wireless communication network can determine a service type of the first node. The first node can transmit, to a second node during a random access procedure, an indication of the service type of the first node. The first node can then establish a connection with a unit of the second node for serving nodes in the wireless network that are associated with the service type. The connection can be established based on transmitting the indication of the service type.

Description

[0001] Cross-references

[0002] This patent application claims the benefit of U.S. Patent Application No. 17 / 082,532, filed October 28, 2020, entitled “UNIT SELECTION FORA NODE”, which has been assigned to the assignee of this application and is expressly incorporated herein by reference. Technical Field

[0003] The following content relates to wireless communication, including cell selection for nodes.

[0004] background

[0005] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, message sending and receiving, broadcasting, and so on. These systems can support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth-generation (4G) systems (such as Long Term Evolution (LTE) systems, LTE-A Advanced (LTE-A) systems, or LTE-A Pro systems) and fifth-generation (5G) systems, which may be referred to as NR systems. These systems can employ various technologies, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), or Discrete Fourier Transform Extended Orthogonal Frequency Division Multiplexing (DFT-S-OFDM). A wireless multiple access communication system may include one or more base stations or one or more network access nodes, each of which simultaneously supports communication from multiple communication devices, which may also be referred to as User Equipment (UE).

[0006] Overview

[0007] The described technology relates to improved methods, systems, devices, and apparatuses for supporting unit selection for nodes. Typically, the described technology provides a first node (such as a donor node) to assist a second node (such as a relay node) in connecting to a unit (such as a central unit) that can be shared with a third node (such as a second donor node). The second node (which may be a relay node) or another device can communicate with the first node the service type of the second node, allowing the first node to selectively connect to the unit (such as a shared central unit), which can be used to serve a first type of node (e.g., a mobile node, such as a mobile relay node).

[0008] A method for wireless communication at a first node in a wireless network is described. The method may include: determining a service type of the first node, the service type indicating that the first node is a mobile node; transmitting an indication of the service type of the first node to a second node during a random access procedure; and establishing a connection with a unit of the second node based on the indication of the service type transmitted during the random access procedure, for serving a node in the wireless network associated with that service type.

[0009] An apparatus for wireless communication at a first node in a wireless network is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. These instructions are executable by the processor to cause the apparatus to: determine a service type of the first node, the service type indicating that the first node is a mobile node; transmit an indication of the service type of the first node to a second node during a random access procedure; and establish a connection with a unit of the second node based on the indication of the service type transmitted during the random access procedure, for serving nodes in the wireless network associated with that service type.

[0010] Another device for wireless communication at a first node in a wireless network is described. The device may include means for: determining a service type of the first node, the service type indicating that the first node is a mobile node; transmitting an indication of the service type of the first node to a second node during a random access procedure; and establishing a connection with a unit of the second node based on the indication of the service type transmitted during the random access procedure, for serving nodes in the wireless network associated with that service type.

[0011] A non-transient computer-readable medium is described, storing code for wireless communication at a first node in a wireless network. The code may include instructions executable by a processor to: determine the service type of the first node, the service type indicating that the first node is a mobile node; transmit an indication of the service type of the first node to a second node during a random access procedure; and establish a connection with a unit of the second node based on the indication of the service type transmitted during the random access procedure, for servicing nodes in the wireless network associated with that service type.

[0012] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, transmitting an indication of a service type may include operations, features, means, or instructions for transmitting an indication of a service type in a request to establish a connection with a second node.

[0013] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, the request includes message 3 of the random access procedure or message A of the random access procedure.

[0014] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, a transmission request may include an operation, feature, means, or instruction for transmitting a second part of an identifier in message 5 of a random access procedure.

[0015] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, transmitting an indication of a type of service may include operations, features, means, or instructions for transmitting an indication of a type of service in an acknowledgment message of a random access procedure.

[0016] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, the acknowledgment message includes message 5 of the random access procedure.

[0017] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, transmitting an indication of a type of service may include operations, features, means, or instructions for transmitting a random access preamble on a set of random access channel resources dedicated to nodes associated with the type of service.

[0018] Some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein may further include operations, features, means or instructions for receiving from a second node a system information block indicating that a random access channel resource set may be dedicated to a node associated with a service type.

[0019] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, the first node includes a relay node, the second node includes a donor node, and the unit includes a central unit of the donor node that can be shared among a set of nodes including the second node.

[0020] In some examples of the methods, apparatus (devices), and non-transient computer-readable media described herein, the type of service indicates a mobile node, and the connection may be a link. In some examples of the methods, apparatus (devices), and non-transient computer-readable media described herein, the first node is a user equipment (UE).

[0021] A method for wireless communication at a first unit of a first node in a wireless network is described. The method may include: receiving an indication of a service type for a second node, the service type indicating that the second node is a mobile node; determining a second unit of the first node based on the service type of the second node to establish a connection with the second node, the second unit being for serving nodes associated with the service type and being a unit in a set of units of the first node; and based on the determination, transmitting a request to the second unit to establish a connection for serving nodes associated with the service type.

[0022] An apparatus for wireless communication at a first unit of a first node in a wireless network is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. These instructions are executable by the processor to cause the apparatus to: receive an indication of a service type for a second node, the service type indicating that the second node is a mobile node; determine a second unit of the first node based on the service type of the second node to establish a connection with the second node, the second unit being for serving nodes associated with the service type and being one of the units in the first node's set of units; and based on the determination, transmit a request to establish a connection to the second unit for serving nodes associated with the service type.

[0023] Another device is described for performing wireless communication at a first unit of a first node in a wireless network. The device may include means for: receiving an indication of a service type for a second node, the service type indicating that the second node is a mobile node; determining a second unit of the first node based on the service type of the second node to establish a connection with the second node, the second unit being for serving nodes associated with the service type and being one of the units in the first node's set of units; and based on the determination, transmitting a request to establish a connection to the second unit for serving nodes associated with the service type.

[0024] A non-transient computer-readable medium is described, storing code for wireless communication at a first unit of a first node in a wireless network. The code may include instructions executable by a processor to: receive an indication of a service type for a second node, the service type indicating that the second node is a mobile node; determine a second unit of the first node based on the service type of the second node to establish a connection with the second node, the second unit being for serving nodes associated with the service type and being one of the units in the first node's set of units; and based on the determination, transmit a request to establish a connection to the second unit for serving nodes associated with the service type.

[0025] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, receiving an indication of a service type may include operations, features, means, or instructions for receiving an indication of a service type in a request from a second node to establish a connection with a first node.

[0026] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, requests from a second node include message 3 of the random access procedure or message A of the random access procedure.

[0027] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, a request from a second node may include an operation, feature, means, or instruction for receiving a second part of an identifier in message 5 of the random access procedure.

[0028] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, a transmission request may include an operation, feature, means, or instruction for transmitting to a second unit a request to serve a node associated with that service type, the request including an indication of the service type of the second node.

[0029] Some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein may further include operations, features, means or instructions for: transmitting an indication of the service type of the second node to the core network based on the establishment of a connection between the second node and a second unit of the node for associating services and service types, and receiving confirmation from the core network that the second node may have the indicated service type.

[0030] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, receiving an indication of a type of service may include operations, features, means, or instructions for actions such as receiving an indication of a type of service in an acknowledgment message from a second node, wherein the acknowledgment message portion of a random access procedure is used to establish a connection with the first node.

[0031] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, the acknowledgment message includes message 5 of the random access procedure.

[0032] In some examples of the methods, apparatus (devices) and nontransient computer-readable media described herein, the connection to the second unit may include operations, features, means, or instructions for: receiving a message from the second node acknowledging that a first connection may have been established with a third unit of the first node, the first connection being usable for serving a node associated with a second service type, wherein the message includes an indication of the service type of the second node; and transmitting an instruction to the third unit for serving a node associated with the second service type, based on the service type of the second node, to release the first connection with the second node, wherein the second connection may have been established based on the instruction to release the first connection.

[0033] Some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein may further include operations, features, devices or instructions for transmitting a request to establish a second connection to a second unit based on the service type of the second node.

[0034] Some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein may further include operations, features, means or instructions for: receiving a request from a second node to establish a radio resource control connection with a first node, and selecting a third unit based on the request to establish a first connection with the second node.

[0035] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, an indication of the type of service may be received from the core network during the registration procedure to a second node.

[0036] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, the connection to the second unit may include operations, features, means, or instructions for: determining that a first connection may have been established between the third unit and the second node and the first node, the first connection being usable for serving a node associated with a second service type; and transmitting a switching command to the third unit based on the service type of the second node, wherein the second connection may be established based on the switching command.

[0037] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, receiving an indication of the service type of a second node may include operations, features, means, or instructions for receiving a random access preamble on a set of random access channel resources dedicated to the node associated with the service type.

[0038] Some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein may further include operations, features, means or instructions for transmitting to a second node a system information block indicating that a random access channel resource set is dedicated to a node associated with a service type.

[0039] In some examples of the methods, apparatus (devices) and non-transient computer-readable media described herein, a second unit of a first node may be separate from the first unit of the first node, and the set of units includes a third unit for serving nodes associated with a second service type, which may be co-located with the first unit, and wherein the second unit may be shared among the set of nodes including the first node. Brief description of the attached diagram

[0041] Figure 1 Examples of wireless communication systems supporting node cell selection according to various aspects of this disclosure are explained.

[0042] Figure 2 Examples of wireless communication systems supporting node cell selection according to various aspects of this disclosure are explained.

[0043] Figure 3 Examples of wireless communication systems supporting node cell selection according to various aspects of this disclosure are explained.

[0044] Figure 4 An example of a process flow supporting the selection of nodes based on various aspects of this disclosure is explained.

[0045] Figure 5 An example of a process flow supporting the selection of nodes based on various aspects of this disclosure is explained.

[0046] Figure 6 An example of a process flow supporting the selection of nodes based on various aspects of this disclosure is explained.

[0047] Figure 7 and 8 A block diagram of a device supporting unit selection for nodes is shown according to various aspects of this disclosure.

[0048] Figure 9 A block diagram of a communication manager supporting cell selection for nodes, according to various aspects of this disclosure, is shown.

[0049] Figure 10 A diagram of a system including a device for supporting cell selection for nodes is shown according to various aspects of this disclosure.

[0050] Figure 11 and 12A block diagram of a device supporting unit selection for nodes is shown according to various aspects of this disclosure.

[0051] Figure 13 A block diagram of a communication manager supporting cell selection for nodes, according to various aspects of this disclosure, is shown.

[0052] Figure 14 A diagram of a system including a device for supporting cell selection for nodes is shown according to various aspects of this disclosure.

[0053] Figure 15 and 16 A flowchart illustrating a method for supporting node cell selection according to various aspects of this disclosure is shown.

[0054] Detailed description

[0055] Some wireless communication systems may support networks (such as Integrated Access and Backhaul (IAB) networks) that include a first node (such as an IAB donor node) and one or more second nodes (such as relay nodes) downstream of the first node. The first node (such as an IAB donor node) may include units (such as a central unit (CU)) for controlling the network and may include one or more second units (such as distributed units (DU)) for scheduling one or more other nodes (such as other IAB nodes). When the network has mobile nodes (such as mobile IAB nodes) (as opposed to non-mobile nodes (such as non-mobile or stationary IAB nodes)), the movement of a node can switch it from a source node (such as a source donor node) to a target node (such as a target donor node). To complete the handover, information (e.g., UE context information, such as security context information) may be passed from the first unit of the source node (such as the CU of the source donor node) to the second unit of the target node (such as the CU of the target donor node). However, passing information between units of different donor nodes can increase latency and signaling overhead, which may negatively impact system or device performance.

[0056] According to the techniques described herein, source nodes (such as source donor nodes) and target nodes (such as target donor nodes) can share units (such as CUs) to avoid transmitting certain information between the two nodes when a node (such as an IAB node) switches from the source node to the target node. This avoids inefficient signaling, which can improve system and device performance. In addition to shared units (such as shared CUs, which may be dedicated to serving first-type nodes, such as IAB nodes (such as mobile IAB nodes)), each node (such as a donor node) may also have units (such as local CUs) dedicated to serving second-type nodes, such as second-type IAB nodes (such as non-mobile IAB nodes). To ensure that a node establishes a connection with the appropriate unit (such as a CU), the node (such as a donor node) may refer to the service type associated with the mobile node (such as an IAB node), which may be provided by the node or the core network, and other examples.

[0057] Although some aspects of this disclosure have been described with reference to IAB networks and related devices, units or nodes, the techniques, processes, operations, methods and apparatus described herein are more broadly applicable to a wide range of networks, devices, units and nodes in various wireless communication environments, and this disclosure should not be construed as limiting unless otherwise specifically indicated.

[0058] The aspects of this disclosure are initially described in the context of wireless communication systems. These aspects are further explained and described by way of process flows, apparatus diagrams, system diagrams, and flowcharts relating to cell selection for nodes.

[0059] Figure 1 Examples of a wireless communication system 100 supporting element selection for nodes according to various aspects of this disclosure are described. The wireless communication system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, an Advanced LTE (LTE-A) network, an LTE-APro network, or a New Radio (NR) network. In some examples, the wireless communication system 100 may support enhanced broadband communication, ultra-reliable (e.g., mission-critical) communication, low latency communication, communication with low-cost and low-complexity devices, or any combination thereof.

[0060] Base station 105 can be distributed across a geographical area to form wireless communication system 100, and can be different types of devices or devices with different capabilities. Base station 105 and UE 115 can communicate wirelessly via one or more communication links 125. Each base station 105 can provide a coverage area 110, and UE 115 and base station 105 can establish one or more communication links 125 on the coverage area 110. Coverage area 110 can be an example of a geographical area over which base station 105 and UE 115 can support signal communication according to one or more radio access technologies.

[0061] Each UE 115 can be distributed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 can be stationary or mobile, or stationary and mobile at different times. Each UE 115 can be a different type of device or a device with different capabilities. Figure 1 The document describes some example UE 115s. The UE 115 described herein can communicate with various types of devices, such as other UE 115s, base station 105, or network equipment (e.g., core network nodes, relay equipment, integrated access and backhaul (IAB) nodes, or other network equipment). Figure 1 As shown in the image.

[0062] Each base station 105 may communicate with the core network 130, or with each other, or both. For example, base station 105 may interface with the core network 130 via one or more backhaul links 120 (e.g., via S1, N2, N3, or other interfaces). Base stations 105 may communicate with each other directly (e.g., directly between base stations 105), indirectly (e.g., via the core network 130), or directly and indirectly on backhaul links 120 (e.g., via X2, Xn, or other interfaces). In some examples, backhaul link 120 may be or include one or more radio links.

[0063] One or more of the base stations 105 described herein may include, or may be referred to by those skilled in the art as, base transceiver station, radio base station, access point, radio transceiver, B node, evolved B node (eNB), next-generation B node or gigabit B node (any of which may be referred to as gNB), home B node, home evolved B node, or other suitable terms.

[0064] UE 115 may include or be referred to as a mobile device, wireless device, remote device, handheld device, or subscriber device, or any other suitable term, wherein "device" may also be referred to as a unit, station, terminal, or client, etc. UE 115 may also include or be referred to as a personal electronic device, such as a cellular phone, personal digital assistant (PDA), tablet computer, laptop computer, or personal computer. In some examples, UE 115 may include or be referred to as a wireless local loop (WLL) station, Internet of Things (IoT) device, Internet of Everything (IoE) device, or machine-type communication (MTC) device, which may be implemented in various objects such as appliances or vehicles, meters, etc.

[0065] The UE 115 described herein can communicate with various types of devices, such as other UEs 115 that sometimes act as relays, as well as base station 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, relay base stations, etc. Figure 1 As shown in the image.

[0066] UE 115 and base station 105 can wirelessly communicate with each other via one or more communication links 125 on one or more carriers. The term "carrier" can refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting communication link 125. For example, a carrier for communication link 125 may include a portion of the radio spectrum band (e.g., a bandwidth portion (BWP)) operating according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling coordinating carrier operation, user data, or other signaling. Wireless communication system 100 may support communication with UE 115 using carrier aggregation or multi-carrier operation. UE 115 may be configured to have multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration. Carrier aggregation may be used in conjunction with both frequency division duplex (FDD) and time division duplex (TDD) component carriers.

[0067] The signal waveform transmitted on the carrier may include multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques, such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform extended OFDM (DFT-S-OFDM)). In a system employing MCM, a resource element may include a symbol period (e.g., the duration of a modulation symbol) and a subcarrier, where the symbol period and subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the code rate of the modulation scheme, or both). Thus, the more resource elements the UE 115 receives and the higher the order of the modulation scheme, the higher the data rate the UE 115 can achieve. Wireless communication resources can refer to a combination of radio frequency spectrum resources, temporal resources, and spatial resources (e.g., spatial layers or beams), and using multiple spatial layers can further improve the data rate or data integrity of communication with the UE 115.

[0068] One or more parameter designs for a carrier can be supported, where the parameter design may include a subcarrier spacing (Δf) and a cyclic prefix. A carrier can be divided into one or more BWPs with the same or different parameter designs. In some examples, UE 115 can be configured with multiple BWPs. In some examples, a single BWP for a carrier can be active at a given time, and communication for UE 115 can be limited to one or more active BWPs.

[0069] The time interval of base station 105 or UE 115 can be expressed as a multiple of a basic time unit, such as the sampling period T. s =1 / (Δf) max ·Nf) seconds, where Δf max The maximum supported subcarrier spacing can be represented by Nf, while Nf can represent the maximum supported Discrete Fourier Transform (DFT) size. The time interval of the communication resources can be organized according to radio frames, each with a specified duration (e.g., 10 milliseconds (ms)). Each radio frame can be identified by a System Frame Number (SFN) (e.g., ranging from 0 to 1023).

[0070] Each frame may include multiple consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some examples, a frame may (e.g., in the time domain) be divided into subframes, and each subframe may be further divided into several time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include several symbol periods (e.g., depending on the length of the cyclic prefix added before each symbol period). In some wireless communication systems 100, time slots may be further divided into multiple mini-time slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., Nf) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0071] A subframe, time slot, mini-slot, or symbol can be the smallest scheduling unit of the wireless communication system 100 (e.g., in the time domain) and can be referred to as a transmission time interval (TTI). In some examples, the duration of the TTI (e.g., the number of symbol periods in the TTI) can be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 can be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

[0072] Physical channels can be multiplexed on a carrier using various techniques. Physical control channels and physical data channels can be multiplexed on a downlink carrier, for example, using one or more of Time Division Multiplexing (TDM), Frequency Division Multiplexing (FDM), or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET)) for physical control channels can be defined by the number of symbol periods and can extend across the system bandwidth or a subset of the system bandwidth of the carrier. One or more control regions (e.g., CORESET) can be configured for a set of UEs 115. For example, one or more UEs 115 can monitor or search control regions for control information based on one or more search space sets, and each search space set can include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. An aggregation level for control channel candidates can refer to the number of control channel resources (e.g., control channel elements (CCEs)) associated with coded information in a control information format having a given payload size. The search space set may include a common search space set configured to send control information to multiple UEs 115 and a UE-specific search space set configured to send control information to a specific UE 115.

[0073] Each base station 105 may provide communication coverage via one or more cells (e.g., macrocells, small cells, hotspots, or other types of cells, or any combination thereof). The term "cell" may refer to a logical communication entity used to communicate with base station 105 (e.g., on a carrier) and may be associated with an identifier used to distinguish adjacent cells (e.g., Physical Cell Identifier (PCID), Virtual Cell Identifier (VCID), or others). In some examples, a cell may also refer to a geographic coverage area 110 or a portion of geographic coverage area 110 (e.g., a sector) on which a logical communication entity operates. The extent of such cells may vary from smaller areas (e.g., structures, subsets of structures) to larger areas depending on various factors (such as the capabilities of base station 105). For example, a cell may be or include buildings, subsets of buildings, or external space between or overlapping geographic coverage areas 110, among other examples.

[0074] In some examples, base station 105 may be mobile, and thus provide communication coverage to mobile geographic coverage areas 110. In some examples, different geographic coverage areas 110 associated with different technologies may overlap, but the different geographic coverage areas 110 may be supported by the same base station 105. In other examples, overlapping geographic coverage areas 110 associated with different technologies may be supported by different base stations 105. Wireless communication system 100 may include, for example, a heterogeneous network, in which different types of base stations 105 use the same or different radio access technologies to provide coverage to various geographic coverage areas 110.

[0075] Wireless communication system 100 may be configured to support ultra-reliable communication or low latency communication, or various combinations thereof. For example, wireless communication system 100 may be configured to support ultra-reliable low latency communication (URLLC) or mission-critical communication. UE 115 may be designed to support ultra-reliable, low latency, or mission-critical functions (e.g., mission-critical functions). Ultra-reliable communication may include private or group communication and may be supported by one or more mission-critical services, such as Mission-Critical Talk-to-Talk (MCPTT), Mission-Critical Video (MCVideo), or Mission-Critical Data (MCData)). Support for mission-critical functions may include prioritization of services, and mission-critical services may be used for public safety or general business applications. The terms ultra-reliable, low latency, mission-critical, and ultra-reliable low latency are used interchangeably herein.

[0076] In some examples, UE 115 may also be able to communicate directly with other UE 115 on a device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UE 115s utilizing D2D communication may be within the geographic coverage area 110 of base station 105. Other UE 115s in such a group may be outside the geographic coverage area 110 of base station 105 or may be unable to receive transmissions from base station 105 for other reasons. In some examples, groups of UE 115s communicating via D2D communication may utilize a one-to-many (1:M) system, where each UE 115 transmits to every other UE 115 in the group. In some examples, base station 105 facilitates the scheduling of resources for D2D communication. In other cases, D2D communication is performed between the individual UE 115s without involving base station 105.

[0077] Core network 130 provides user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. Core network 130 can be an evolved packet core (EPC) or a 5G core (5GC). The EPC or 5GC may include at least one control plane entity (e.g., a Mobility Management Entity (MME), Access and Mobility Management Function (AMF)) managing access and mobility, and at least one user plane entity (e.g., a Serving Gateway (S-GW), Packet Data Network (PDN) Gateway (P-GW), or User Plane Function (UPF)) routing packets or interconnecting to external networks. The control plane entity manages non-access stratum (NAS) functions, such as mobility, authentication, and bearer management of UE 115 served by base station 105 associated with core network 130. User IP packets can be delivered through the user plane entity, which provides IP address allocation and other functions. The user plane entity may be connected to one or more network operator IP services 150. The IP service 150 may include access to the Internet, intranet, IP Multimedia Subsystem (IMS), or packet-switched streaming services.

[0078] Some network devices (such as base station 105) may include sub-components, such as access network entity 140, which may be an example of an access node controller (ANC). Each access network entity 140 may communicate with each UE 115 through one or more other access network transport entities 145, which may be referred to as a radio headend, smart radio headend, or transmit / receive point (TRP). Each access network transport entity 145 may include one or more antenna panels. In some configurations, the various functions of each access network entity 140 or base station 105 may be distributed across various network devices (e.g., radio headends and ANCs) or combined into a single network device (e.g., base station 105).

[0079] Wireless communication system 100 can operate using one or more frequency bands, typically in the range of 300 MHz to 300 GHz. Generally, the 300 MHz to 3 GHz band is referred to as a UHF band or decimeter band because the wavelengths range from approximately 1 decimeter to 1 meter. UHF waves can be blocked or redirected by buildings and environmental features, but these waves can penetrate various structures sufficiently for macrocells to provide service to UE 115 located indoors. Compared to transmissions using smaller frequencies and longer waves in the lower HF or VHF portions of the spectrum below 300 MHz, UHF wave transmission can be associated with smaller antennas and shorter ranges (e.g., less than 100 km).

[0080] Wireless communication system 100 may utilize both licensed and unlicensed radio spectrum bands. For example, wireless communication system 100 may employ licensed assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology in unlicensed frequency bands (such as the 5 GHz Industrial, Scientific, and Medical (ISM) band). When operating in unlicensed radio spectrum bands, devices (such as base station 105 and UE 115) may employ carrier sensing for collision detection and avoidance. In some examples, operation in unlicensed frequency bands may be based on carrier aggregation configuration (e.g., LAA) in coordination with component carriers operating in licensed frequency bands. Operation in unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, etc.

[0081] Base station 105 or UE 115 may be equipped with multiple antennas that can be used to employ technologies such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communication, or beamforming. The antennas of base station 105 or UE 115 may be located within one or more antenna arrays or antenna panels that can support MIMO operation or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may coexist at an antenna assembly (such as an antenna tower). In some examples, the antennas or antenna arrays associated with base station 105 may be located in different geographical locations. Base station 105 may have an antenna array with several rows and columns of antenna ports that base station 105 can use to support beamforming for communication with UE 115. Similarly, UE 115 may have one or more antenna arrays that can support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support radio frequency beamforming for signals transmitted via the antenna ports.

[0082] Beamforming (also known as spatial filtering, directional transmission, or directional reception) is a signal processing technique that can be used at a transmitting or receiving device (e.g., base station 105, UE 115) to shape or guide an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting and receiving devices. Beamforming can be achieved by combining signals transmitted via antenna elements of an antenna array, such that some signals propagating relative to a particular orientation of the antenna array experience constructive interference, while others experience destructive interference. Adjustments to the signals transmitted via the antenna elements may include the transmitting or receiving device applying amplitude offset, phase offset, or both to the signals carried via the antenna elements associated with that device. The adjustments associated with each antenna element may be defined by a beamforming weight set associated with a particular orientation (e.g., the antenna array relative to the transmitting or receiving device, or relative to some other orientation).

[0083] Wireless communication system 100 can be a packet-based network operating according to a layered protocol stack. In the user plane, communication at the bearer or Packet Data Convergence Protocol (PDCP) layer can be IP-based. The Radio Link Control (RLC) layer performs packet segmentation and reassembly for communication on logical channels. The Media Access Control (MAC) layer performs priority handling and multiplexing of logical channels into transport channels. The MAC layer can also use error detection, error correction, or both to support MAC layer retransmissions to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer can provide the establishment, configuration, and maintenance of RRC connections between UE 115 and base station 105 or core network 130 supporting user plane data radio bearers. At the physical layer, transport channels can be mapped to physical channels.

[0084] In some cases, the wireless communication system 100 may be an example of a network (e.g., a wireless backhaul communication network such as an IAB network), among other various examples. An IAB network may include an IAB donor (or "anchor") node and one or more relay (or "intermediate") nodes downstream of the donor node. The IAB network may share resources between the access and backhaul links so that access traffic can be relayed on the wireless backhaul link. In some cases, the same techniques and skills may be used for both the access link and the backhaul link. The IAB donor node may provide access to the child UE and wireless backhaul functionality to the IAB node. The IAB donor may include a CU for controlling the IAB network and one or more DUs for scheduling the IAB nodes. The IAB donor may have a wired connection to the core network 130. Downstream of the IAB donor node, the network may include one or more IAB nodes within the IAB network (also referred to as parent nodes, relay nodes, intermediate nodes, or child nodes, depending on the node's location within the IAB network). Each IAB node wirelessly relays traffic from one or more other nodes, such as its child nodes (e.g., the UE or other IAB nodes), to one or more other nodes, such as the parent node (e.g., the IAB donor or IAB node). UE 115 may wirelessly connect to the IAB donor node within its range. In some cases, base station 105 may be an example of a donor IAB node.

[0085] In some examples, an IAB node can be a mobile IAB node capable of moving from one location to another. When an IAB node changes location, it may be beneficial for the IAB node to be switched from the source donor node serving it to a target IAB node that is better suited to provide connectivity and access to the IAB node given its new location. As part of the handover procedure, context information of the UE 115 served by the IAB node can be communicated from the CU of the source donor node to the CU of the target donor node. However, communicating context information between the CUs of different donor nodes can increase overhead signaling and require various resources, time, and power, which may negatively impact system performance (e.g., overhead signaling may waste radio resources, increase donor node power consumption, and increase latency, among other disadvantages).

[0086] According to the techniques described herein, the source donor node and the target donor node can share a CU to avoid passing context information between the two donor nodes when an IAB node is switched from the source donor node to the target donor node. The shared CU can be configured (e.g., dedicated to) serving mobile IAB nodes and can be decoupled from the donor node's DU (e.g., at a distributed server). In addition to the shared CU, each donor node may also have a local CU dedicated to serving non-mobile IAB nodes. To ensure that mobile IAB nodes establish connections with the appropriate CU (e.g., the shared CU), the donor node can reference the service type associated with the mobile IAB node, which indicates the IAB node's mobility capabilities. The shared CU may also be referred to as a centralized CU or other suitable terms.

[0087] Although some aspects of this disclosure have been described with reference to IAB networks and related devices, units or nodes, the techniques, processes, operations, methods and apparatus described herein are more broadly applicable to different networks, devices, units and nodes in different wireless communication environments, and this disclosure should not be construed as limiting unless otherwise specifically indicated.

[0088] Figure 2 Examples of wireless communication systems 200 supporting element selection for nodes according to various aspects of this disclosure are described. Wireless communication system 200 (e.g., a new radio (NR) system, millimeter-wave (mmW) system) can provide an IAB network architecture by supplementing wired backhaul connections (e.g., wired backhaul link 220) with shared infrastructure and spectrum resources for network access with wireless backhaul link capabilities. Wireless communication system 200 may include a core network 205 and one or more base stations or supported devices, which are broken down into one or more supporting entities (i.e., functionalities) for collaboratively enhancing wireless backhaul density with communication access. The supporting functionalities of the base stations may be referred to as IAB nodes, such as IAB donor nodes 210 and IAB nodes 215. Wireless communication system 200 may additionally support several UEs 115 that can communicate on the uplink with one or more IAB donor nodes 210, IAB nodes 215, or a combination of these devices. In some examples, wireless communication system 200 may implement aspects of wireless communication system 100.

[0089] The wireless communication system 200 may include one or more IAB donor nodes 210, which may interface between one or more components in a wired network and one or more components in a wireless network. In some cases, the IAB donor node 210 may be referred to as an anchor node because the IAB donor node 210 anchors the wireless network to the wired connection. For example, each IAB donor node 210 may include at least one wired backhaul link 220 and one or more additional links (e.g., wireless backhaul link 225, backup wireless backhaul link 230, access link 235).

[0090] IAB donor node 210 can be functionally decomposed into associated base station central unit (CU) and distributed unit (DU) entities (or "functions"), wherein one or more DUs associated with IAB donor node 210 can be partially controlled by the associated CU. The CU of IAB donor node 210 can store Layer 3 (L3) functionality (e.g., RRC, Serving Data Adaptation Protocol (SDAP), PDCP) and signaling. Furthermore, the CU of IAB donor node 210 can communicate with core network 205 over wired backhaul link 220 (e.g., which may be referred to as the NG interface). The DU can store lower-layer operations, such as Layer 1 (L1) or Layer 2 (L2) functionality (e.g., RLC, MAC, physical layer) and signaling. The DU entities of IAB donor node 210 can support serving cells within the network coverage area based on the connections associated with the radio backhaul link 225 and access link 235 of the IAB network. The DU of IAB donor node 210 can control both the access links and backhaul links within the corresponding network coverage area, and can provide control and scheduling for descendant (i.e., child, relay) IAB nodes 215 and / or UE 115. For example, the DU can support RLC channel connections with UE 115 (e.g., via access link 235) or with IAB node 215 (e.g., via backhaul links, such as primary radio backhaul link 225 or backup radio backhaul link 230). The DU of node 215 can be responsible for relaying (e.g., passing, forwarding) messages from another node (e.g., to CU and / or core network 205) so that the other node can register with core network 205 and establish a Secure Radio Resource Control (RRC) connection with the CU of donor node 210.

[0091] In some examples, IAB node 215 can be functionally split into associated mobile terminal (MT) and base station DU entities, where the MT functionality of IAB node 215 can be controlled or scheduled by a predecessor (i.e., parent) IAB node via a radio backhaul link. The parent node of IAB node 215 can be another (predecessor) IAB node 215 or donor node 210. The MT functionality can be similar to the functionality performed by UE 115 in the system. IAB node 215 may not be directly connected to wired backhaul link 220. Instead, IAB node 215 can connect to core network 205 via a radio backhaul link through other IAB nodes (e.g., any number of additional IAB nodes 215 and IAB donor nodes 210). IAB node 215 can use the MT functionality to transmit upstream in the IAB system (e.g., towards core network 205). In some scenarios, the DU of IAB node 215 may be partially controlled by signaling messages (e.g., transmitted via the F1 Application Protocol (F1-AP)) from the CU entity of the associated IAB donor node 210. The DU of IAB node 215 may support serving cells within the network coverage area. For example, the DU of IAB node 215 may perform the same or similar functions as the DU of IAB donor node 210, thereby supporting one or more access links 235 for UE 115, one or more radio backhaul links for downstream IAB node 215, or both. In some examples, IAB node 215 is a device (such as a base station or UE) (e.g., UE 115 may be an IAB node).

[0092] Wireless communication system 200 may employ relay links for communication within the IAB network architecture. For example, UE 115 may communicate with IAB nodes, and IAB nodes may relay data to base station CU or core network 205, either directly or via one or more IAB nodes 215. Each IAB node 215 may include a primary wireless backhaul link 225 for relaying data upstream or receiving information from base station CU or core network 205. In some cases, IAB node 215 may additionally include one or more backup wireless backhaul links 230 (e.g., for redundant connectivity or improved robustness). If the primary wireless backhaul link 225 fails (e.g., due to interference, a failure at a connected IAB node, IAB node relocation, or maintenance at an IAB node), IAB node 215 may use the backup wireless backhaul link 230 for backhaul communication within the IAB network. The first (e.g., primary) wireless backhaul link 225 may be associated with a coverage area, and MT functionality may be controlled or scheduled by a first parent node. One or more secondary backhaul links (e.g., backup wireless backhaul link 230) may be associated with coverage areas that are not co-located and controlled or scheduled by one or more parent nodes.

[0093] Each of the primary backhaul connections and one or more secondary connections can support spectrum capabilities to provide network communication on one or more RATs. One or more IAB nodes can further support base station DU entities and can support multiple backhaul and access links within the relay chain. The DU entity can control or schedule descendant IAB nodes 215 and UE 115 within the IAB network (e.g., downstream in the IAB network) via configured backhaul and access links. That is, based on the established backhaul and access connections, IAB node 215 can act as a relay between IAB donor node 210 and one or more descendant devices (e.g., other IAB nodes 215, UE 115) in both communication directions.

[0094] In some examples, IAB node 215 may be a mobile IAB node (or other type of IAB node) capable of moving, for example, from one location to another. When IAB node 215 changes location, or for other reasons, it may be beneficial to switch IAB node 215 from a source IAB donor node (e.g., IAB donor node 210-a) to a target IAB node (e.g., IAB donor node 210-b) that is more suitable for providing connectivity and access to IAB node 210. As part of the handover procedure, context information of the UEs served by IAB node 215 can be communicated from the CU of the source IAB donor node 210-a to the CU of the target IAB donor node 210-b. However, communicating context information between the CUs of different IAB donor nodes 210 may increase overhead signaling (e.g., handover signaling to all UEs connected to IAB node 215), which may negatively impact system performance.

[0095] According to the techniques described herein, two nodes in a network (e.g., source IAB donor node 210-a and target IAB donor node 210-b) can share a unit (e.g., a CU) such that when another node (e.g., IAB node 215) is switched from one node to the other (e.g., from source IAB donor node 210-a to target IAB donor node 210-b), the transfer of context information between the two nodes (e.g., the two IAB donor nodes) is avoided. Such a configuration can logically be represented as a single IAB donor node, where the CU is shared and multiple DUs (one or more DUs belonging to the source and one or more DUs belonging to the target) are connected to that CU.

[0096] The shared unit may be dedicated to serving first-type nodes (such as IAB nodes (e.g., mobile IAB nodes)) and may be distributed (e.g., at a distributed server) to other units (such as the DU of IAB donor node 210). In addition to the shared unit, each IAB donor node 210 may also have a local unit (such as a local CU) configured (e.g., dedicated to) serving second-type nodes (such as IAB nodes (e.g., non-mobile IAB nodes)). To ensure that a node (such as IAB node 215) connects to the appropriate unit (such as the appropriate CU), another node (such as IAB donor node 210) may refer to the service type associated with the node (such as IAB node 215), which may be provided by the node (such as IAB node 215) or the core network 205.

[0097] Although some aspects of this disclosure have been described with reference to IAB networks and related devices, units or nodes, the techniques, processes, operations, methods and apparatus described herein are more broadly applicable to a wide range of networks, devices, units and nodes in various wireless communication environments, and this disclosure should not be construed as limiting unless otherwise specifically indicated.

[0098] Figure 3 Examples of a wireless communication system 300 supporting element selection for nodes according to various aspects of this disclosure are described. In some examples, the wireless communication system 300 may implement various aspects of an IAB network architecture and may therefore include donor nodes 310 and nodes 315 (e.g., relay nodes). Each donor node 310 may include corresponding CU 330 and DU 340, which may respectively refer to Figure 2 Examples of CU and DU functionality described. Node 315 may include MT 345 and DU350, which may be referenced respectively. Figure 2 Examples of described MT and DU functionality. Donor nodes 310 may share a common CU (such as CU 330-c) to reduce signaling between donor nodes 310 during, for example, handover between donor nodes 310.

[0099] Donor node 310-a may serve node 315 (e.g., provide wireless connectivity to node 315), which may be a first-type node (e.g., a mobile node) serving multiple UEs 320. For example, node 315 may be coupled to a transport vehicle 325 or other equipment traveling to various geographic locations. When node 315 changes location, it may be advantageous to switch node 315 from donor node 310-a (referred to as the source node) to donor node 310-b (referred to as the target node). In order to serve node 315, CU 330-b of donor node 310-b may need the context information (e.g., security context information, security keys) and other information of the UEs 320 served by node 315. However, passing the context information of UEs 320 from CU 330-a to CU 330-b in this manner may increase overhead signaling during handover procedures, as well as other disadvantages.

[0100] To avoid sending signaling notifications for context information between CUs, donor node 310 may share a unit (such as a CU) configured (e.g., dedicated to) serving a first type of node (e.g., a node associated with a first service type). For example, donor node 310-a and donor node 310-b may share CU 330-c. Thus, each donor node may have two CUs: a first (shared) CU dedicated to serving the first type of node (e.g., a node associated with a first service type, such as a mobile node), and a second CU dedicated to serving the second type of node (e.g., a node associated with a second service type, such as a non-mobile node). In some examples, the CU dedicated to serving the second type of node may be co-located with a donor node's DU, while the CU dedicated to serving the first type of node may be separate from the donor node's DU. For example, CU 330-c may be a "cloud" CU located at server 335, which is physically removed from DUs 340-a and DU 340-b.

[0101] By sharing CU 330-c, donor node 310 can avoid transmitting context information for UE 320 during handover procedures between donor nodes 310, since the security context information is already at CU 330-c. Therefore, for the purpose of UE context information, the handover between donor node 310-a and donor node 310-b can be considered an intra-CU handover, not an inter-CU handover. To ensure that the context information for UE 320 is at CU 330-c instead of CU 330-a, for example, after node 315 initially registers with the core network, donor node 310-a can assist node 315 in connecting to CU 330-c instead of CU 330-a. For this purpose, donor node 310-a can implement aspects of process flow 400, process flow 500, or process flow 600, or any combination thereof, as described respectively. Figure 4 , Figure 5 and Figure 6 As described.

[0102] It should be understood that nodes and units in the wireless communication system 300 can communicate on the Uu interface, the F1 interface, and other interfaces. For example, DU 350 can communicate with the CU of the donor node on the F1 interface, which may include a control plane (e.g., F1-C) and a user plane (e.g., F1-U). MT 345 of node 315 can communicate with the donor node on the Uu interface. The F1 and Uu interfaces can also be used for communication between the donor node and CU 330-c. Therefore, nodes and units in the wireless communication system 300 can exchange information using F1 communication and Uu communication. Although some aspects of this disclosure have been described with reference to IAB networks and related devices, units, or nodes, the techniques, processes, operations, methods, and apparatus described herein are more broadly applicable to different networks, devices, units, and nodes in different wireless communication environments, and this disclosure should not be construed as limiting unless specifically indicated otherwise.

[0103] Figure 4 Examples of a process flow 400 supporting node selection according to various aspects of this disclosure are described. In some examples, process flow 400 may be implemented by devices in the IAB network, such as node 405 (e.g., a relay node) and donor node 410. Donor node 410 may include distributed unit 415, central unit 420-a, and central unit 420-b. Central unit 420-a may be dedicated to serving nodes of a first type (e.g., nodes associated with a first service type, such as non-mobile nodes), while central unit 420-b may be dedicated to serving nodes of a second type (e.g., nodes associated with a second service type, such as mobile nodes). In some examples, node 405 is a UE or other type of device.

[0104] In some examples, central unit 420-a may be dedicated to (e.g., exclusively for) donor node 410, while central unit 420-b may be shared with another donor node (or multiple other donor nodes). Although physically, donor node 410 may be considered to include distributed unit 415 and central unit 420, logically or conceptually, donor node 410 may be considered to include distributed unit 415, central unit 420, and one or more additional distributed units (physically) belonging to one or more different donor nodes. Therefore, distributed unit 415 may be considered to share multiple central units 420. In some examples, central unit 420-a may be co-located with (e.g., coupled to) distributed unit 415, while central unit 420-b may be physically separate from distributed unit 415. Alternatively, central unit 420-b may be co-located with distributed unit 415.

[0105] When node 405 is a mobile node, donor node 410 can assist node 405 in connecting to central unit 420-b (e.g., instead of central unit 420-a) to ensure that the context information of the UE served by node 405 is present at central unit 420-b when a handover procedure occurs. If central unit 420-b is shared with the target donor node for handover procedures, the presence of context information at central unit 420-b can reduce overhead signaling between donor node 410 and the target donor node during the handover procedure, among other advantages.

[0106] At 425, node 405 may transmit a request to distributed unit 415 to establish connectivity (e.g., Radio Resource Control (RRC) connectivity) with donor node 410. This request may include an indication of the type of service associated with node 405. In some examples, node 405 may be a mobile node, and the type of service may indicate the mobility capabilities of node 405. Therefore, in some examples, node 405 may determine the type of service associated with node 405 before initiating a random access procedure. In some examples, the request may be an RRC Setup Request message for a random access procedure (e.g., message 3). Alternatively, in some examples, node 405 may determine the type of service associated with node 405 after initiating a random access procedure.

[0107] The service type can be indicated explicitly or implicitly. For example, the service type can be explicitly indicated by one or more reserved bits or a reason code (e.g., included in message 3). In some examples, one or more bits reserved for the identifier (ID) of node 405 (or bits reserved for the ID of the UE served by node 405) can be reused to explicitly indicate the service type. For example, the ID included in message 3 can be shortened by x bits, and these x bits can be used to indicate the service type. In some examples, x bits are the least significant bit (LSB) or most significant bit (MSB) of the ID. When x bits of the ID are used to indicate the service type, the reserved bits of the ID may be sufficient to resolve contention, and the remaining bits of the ID can be included in a subsequent message (e.g., message 5).

[0108] In some examples, the service type can be indicated in the random access procedure earlier than depicted in process flow 400. For example, the service type can be implicitly indicated by a set of random access resources (e.g., random access channel (RACH) resources) used by node 405 to transmit a random access preamble that initiates the random access procedure. This set of random access resources can be reserved for nodes of a first type (e.g., mobile nodes), while a different set can be reserved for nodes of a second type (e.g., non-mobile nodes). In some examples, donor node 410 can configure or indicate the set of random access resources associated with different services via a system information block (e.g., SIB1) broadcast by donor node 410.

[0109] At 430, distributed unit 415 may select a central unit to fulfill a request based on the service type associated with node 405 and one or more other criteria. For example, if node 405 is a non-mobile node, distributed unit 415 may select central unit 420-a. As another example, if node 405 is a mobile node, distributed unit 415 may select central unit 420-b. In some examples, each central unit 420 may be configured to handle radio resource control messages (as opposed to distributed unit 415).

[0110] At 435, distributed unit 415 may transmit (e.g., forward, relay, or otherwise indicate) a connectivity request to a selected central unit (e.g., central unit 420-b) for processing. This request may include an indication of the type of service associated with node 405. In some examples, this request may be an F1 initial UL RRC message, which includes information for RRC connection such as gNB CU UE F1-APID, the NR Cell Global Identifier (CGIA) associated with donor node 410 or central unit 420-b (which may include the base station ID and / or the cell ID associated with donor node 410 or central unit 420-b), the Cell Radio Network Temporary Identifier (C-RNTI) of the cell associated with donor node 410, and / or the RRC container, etc.

[0111] At 440, central unit 420-b may transmit an RRC information message to distributed unit 415 based on a request received at 435. In some examples, the RRC information message may be an F1-DL RRC delivery message, which includes information for RRC connection, such as gNB CU / DU UE F1AP ID, Signaling Radio Bearer (SRB) ID, and / or RRC container information. In some examples, the information in the RRC information message and / or the transmission of the RRC information message is based on the service type associated with node 405.

[0112] At 445, distributed unit 415 may transmit an RRC setup message provided by central unit 420-b to node 405 based on the RRC information message received at 440. The RRC setup message may include information for RRC connection. In some examples, the RRC setup message is an RRCSetup (RRC Setup) message of the random access procedure (e.g., message 4). At 450, node 405 may transmit an acknowledgment message to distributed unit 415 based on the RRC setup message received at 445. The acknowledgment message may indicate that node 405 has established an RRC connection with central unit 420-b based on the information in the RRC setup message. Therefore, node 405 can establish an RRC connection with central unit 420-b of donor node 410, which allows for overhead-reduced signaling handover between donor nodes (“inter-donor handover”). For example, when an RRC connection is established, the central unit 420-b can establish or obtain context information of the UE served by the node 405. Due to the shared nature of the central unit 420-b, this context information does not need to be passed to another central unit during handover between donor nodes.

[0113] In some examples, distributed unit 415 may transmit an indication to the core network of the service type associated with node 405, enabling the core network to verify the service type. Distributed unit 415 may transmit this indication to the core network after node 405 and central unit 420-a establish an RRC connection, or at another time during process flow 400. In response to transmitting the indication, distributed unit 415 may receive a message from the core network affirming or rejecting the service type provided by node 405. The core network may verify the service type associated with node 405 based on a subscription profile for node 405 (e.g., an IAB node subscription profile). Therefore, the core network may authorize central unit 420-b to provide services to node 405.

[0114] After establishing an RRC connection with the central unit 420-b, the distributed unit 415 can relay messages between the node 405 and the central unit 420-b (and possibly the core network) to enable relevant devices to execute the integration procedure 455. The integration procedure 455 may involve multiple sub-procedures, such as registration procedures, radio link control (RLC) channel and F1 establishment procedures, and / or authentication procedures.

[0115] Therefore, donor node 410 can assist node 405 in connecting to central unit 420-b (instead of central unit 420-a) to ensure that the context information of the UE served by node 405 is present at central unit 420-b when a handover procedure occurs. Although described with reference to RRC connections, the techniques described herein can be implemented for other types of connections.

[0116] Alternative examples of process flow 400 may be implemented, in which some operations are performed in a different order than described, in parallel, or not at all. In some cases, each operation may include additional features not mentioned below, or further operations may be added. Additionally, some operations may be performed multiple times, or combinations of operations may be repeated or cyclical. Although some aspects of this disclosure have been described with reference to IAB networks and related devices or nodes, the techniques, processes, operations, methods, and devices described herein are more broadly applicable to different networks, devices, and nodes in different wireless communication environments, and this disclosure should not be construed as limiting unless specifically indicated otherwise.

[0117] Figure 5Examples of a process flow 500 supporting node selection according to various aspects of this disclosure are described. In some examples, process flow 500 may be implemented by devices in the IAB network, such as node 505 (e.g., a relay node) and donor node 510. Donor node 510 may include distributed unit 515, central unit 520-a, and central unit 520-b. Central unit 520-a may be dedicated to serving nodes of a first type (e.g., nodes associated with a first service type, such as non-mobile nodes), while central unit 520-b may be dedicated to serving nodes of a second type (e.g., nodes associated with a second service type, such as mobile nodes). In some examples, node 505 is a UE or other type of device.

[0118] In some examples, central unit 520-a may be exclusively dedicated to donor node 510, while central unit 520-b may be shared with another donor node (or multiple other donor nodes). Although physically, donor node 510 may be considered to include distributed unit 515 and central unit 520, logically or conceptually, donor node 510 may be considered to include distributed unit 515, central unit 520, and one or more additional distributed units (physically) belonging to one or more different donor nodes. Therefore, distributed unit 515 may be considered to share multiple central units 520. In some examples, central unit 520-a may be co-located with distributed unit 515, while central unit 520-b may be physically separate from distributed unit 515. Alternatively, central unit 520-b may be co-located with distributed unit 515.

[0119] Donor node 510 may assist node 505 in connecting to central unit 520-b (instead of central unit 520-a) to ensure that the context information of the UE served by node 505 is present at central unit 520-b when a handover procedure occurs. If central unit 520-b is shared with the target donor node for handover procedures, the presence of context information at central unit 520-b can reduce overhead signaling between donor node 510 and the target donor node during the handover procedure.

[0120] At 525, node 505 may send a request to distributed unit 515 to establish connectivity (e.g., RRC connectivity) with donor node 510. In some examples, this request may be an RRCSetupRequest message of the random access procedure (e.g., message 3). At 530, distributed unit 515 may select a random or default central unit (e.g., central unit 520-a) based on the request received at 525. In some examples, distributed unit 515 may select a random or default central unit because donor node 410 lacks certain shared terrestrial mobile network (PLMN) information.

[0121] At 535, distributed unit 515 may transmit (e.g., forward, relay, or otherwise indicate) a request for RRC connectivity to a selected central unit (e.g., central unit 520-a). In some examples, this request may be an F1 initial ULRRC message, which includes information for RRC connectivity such as gNB CU UE F1AP ID, NR CGIA (which may include the base station ID and / or cell ID associated with donor node 510 or central unit 520-a), cellular radio network temporary identifier (C-RNTI), and / or RRC container information.

[0122] At 540, the central unit 520-a can transmit an RRC information message to the distributed unit 515 based on a request received at 535. In some examples, the RRC information message may be an F1-DL RRC delivery message, which includes information for RRC connection, such as gNB CU / DU UE F1AP ID, SRB ID, and / or RRC container information.

[0123] At 545, distributed unit 515 may transmit an RRC setup message to node 505 based on the RRC information message received at 540. The RRC setup message may include information for RRC connection. In some examples, the RRC setup message is an RRCSetup (RRC Setup) message of the random access procedure (e.g., message 4).

[0124] At 550, node 505 may transmit an acknowledgment message to distributed unit 515 based on the RRC setup message received at 545. This acknowledgment message may include an indication of the service type associated with node 505. In some examples, node 505 may be a mobile node, and the service type may indicate the mobility capabilities of node 505. The acknowledgment message may indicate that node 505 has established an RRC connection with central unit 520-a based on the information in the RRC setup message. Therefore, central unit 520-a may establish a first RRC connection with node 505, and in doing so, determine the context information associated with node 505 (e.g., context information for node 505 and / or context information for the UE served by node 505).

[0125] At 555, distributed unit 515 may reselect a central unit based on the service type associated with node 505. For example, distributed unit 515 may select central unit 520-b based on the fact that node 505 is a mobile node. At 560, distributed unit 515 may transmit a release message to central unit 520-a, instructing central unit 520-a to release the context information and / or first RRC connection associated with node 505. In some examples, the release message is an F1-UE context release request message, indicating information about the context information and / or RRC connection to be released (e.g., gNB CU UEF1AP ID). In some examples, the release message may indicate the reason for the release (e.g., the release message may indicate that the release is due to the service type of node 505).

[0126] At 565, distributed unit 515 may transmit (e.g., forward, relay, or otherwise indicate) a request for RRC connectivity to central unit 520-b. For example, distributed unit 515 may forward message 3 and / or message 5 to central unit 520-b. Distributed unit 515 may transmit the request at 555 based on the selection of central unit 520-b. In some examples, the request may be an F1 initial UL RRC message, which includes information for RRC connection, such as gNB CU UE F1AP ID, NRCGIB (which may be the same as or different from NR CGIA), C-RNTI, and RRC container. NR CGIB may include the base station ID and / or cell ID associated with donor node 510 or central unit 520-b. At 570, central unit 520-a may transmit a release confirmation message to distributed unit 515, indicating that central unit 520-a has released the context information and / or first RRC connection associated with node 505.

[0127] Therefore, a second RRC connection can be established between node 505 and central unit 520-b, which allows for donor node handover with reduced overhead signaling. For example, upon establishing the RRC connection, central unit 520-b can establish or obtain context information of the UE served by node 505. Due to the shared nature of central unit 520-b, this context information does not need to be passed to another central unit during donor node handover. In some examples, the UE's context information can be passed from central unit 520-a to central unit 520-b (e.g., via an inter-CU tunnel).

[0128] After establishing an RRC connection with the central unit 520-b, the distributed unit 515 can relay messages between node 505 and the central unit 520-b (and possibly the core network) so that relevant devices can execute integration procedures at 575. The integration procedures may involve multiple sub-procedures, such as registration procedures, RLC channel and F1 setup procedures, and / or authentication procedures.

[0129] Therefore, donor node 510 may assist node 505 in connecting to central unit 520-b (instead of central unit 520-a) so that when a handover procedure occurs between donor nodes, the context information of the UE served by node 505 is present at central unit 520-b. Although described with reference to RRC connections, the techniques described herein can be implemented for other types of connections. Alternative examples of process flow 500 may be implemented, in which some operations are performed in a different order than described, in parallel, or not at all. In some cases, each operation may include additional features not mentioned below, or further operations may be added. Additionally, some operations may be performed multiple times, or combinations of operations may be repeated or cyclical. Although some aspects of this disclosure are described with reference to IAB networks and related devices or nodes, the techniques, processes, operations, methods, and devices described herein are more broadly applicable to different networks, devices, and nodes in different wireless communication environments, and this disclosure should not be construed as limiting unless specifically indicated otherwise.

[0130] Figure 6 Examples of a process flow 600 supporting node selection according to various aspects of this disclosure are described. In some examples, process flow 600 may be implemented by devices in the IAB network, such as node 605 (e.g., a relay node) and donor node 610. Donor node 610 may include distributed unit 615, central unit 620-a, and central unit 620-b. Central unit 620-a may be dedicated to serving nodes of a first type (e.g., nodes associated with a first service type, such as non-mobile nodes), while central unit 620-b may be dedicated to serving nodes of a second type (e.g., nodes associated with a second service type, such as mobile nodes). In some examples, node 605 is a UE or other type of device.

[0131] In some examples, central unit 620-a may be dedicated to donor node 610, while central unit 620-b may be shared with another donor node (or multiple other donor nodes). Although physically, donor node 610 may be considered to include distributed unit 615 and central unit 620, logically or conceptually, donor node 610 may be considered to include distributed unit 615, central unit 620, and one or more additional distributed units (physically) belonging to one or more different donor nodes. Therefore, distributed unit 615 may be considered to share multiple central units 620. In some examples, central unit 620-a may be co-located with distributed unit 615, while central unit 620-b may be physically separate from distributed unit 615. Alternatively, central unit 620-b may be co-located with distributed unit 615.

[0132] Donor node 610 may assist node 605 in connecting to central unit 620-b (instead of central unit 620-a) to ensure that the context information of the UE served by node 605 is present at central unit 620-b when a handover procedure occurs. If central unit 620-b is shared with the target donor node for handover procedures, the presence of context information at central unit 620-b reduces overhead signaling between donor node 610 and the target donor node during the handover procedure.

[0133] At 630, node 605 may send a request to distributed unit 615 to establish connectivity (e.g., RRC connectivity) with donor node 610. In some examples, this request may be an RRCSetupRequest message of the random access procedure (e.g., message 3). At 635, distributed unit 615 may select a random or default central unit (e.g., central unit 630-a) based on the request received at 630.

[0134] At 640, distributed unit 615 may transmit (e.g., forward, relay, or otherwise indicate) a request for RRC connectivity to a selected central unit (e.g., central unit 620-a). In some examples, this request may be an F1 initial ULRRC message, which includes information for RRC connectivity, such as gNB CU UE F1AP ID, NR CGIA, C-RNTI, and / or RRC container information.

[0135] At 645, the central unit 620-a can transmit an RRC information message to the distributed unit 615 based on a request received at 640. In some examples, the RRC information message may be an F1-DL RRC delivery message, which includes information for RRC connection, such as gNB CU / DU UE F1AP ID, SRB ID, and / or RRC container information.

[0136] At 650, distributed unit 615 may transmit an RRC setup message to node 605 based on the RRC information message received at 645. The RRC setup message may include information for RRC connection. In some examples, the RRC setup message is an RRCSetup (RRC Setup) message of a random access procedure (e.g., message 4). At 655, node 605 may transmit an acknowledgment message to distributed unit 615 based on the RRC setup message received at 645. The acknowledgment message may indicate that node 605 has established an RRC connection with central unit 620-a based on the information in the RRC setup message. Therefore, central unit 620-a may establish a first RRC connection with node 605. In some examples, central unit 620-a may also determine context information associated with node 605 (e.g., context information for node 605 and / or context information of the UE served by node 605).

[0137] At 660, node 605 may perform (e.g., via donor node 610) a first (e.g., initial) phase of the integration procedure with core network 625. The initial phase of the integration procedure may include a registration procedure and may be based on the establishment of a first RRC connection between node 605 and central unit 620-a. During the registration procedure, distributed unit 615 may receive an indication from the core network (e.g., from AMF) of the type of service associated with node 605. In some examples, node 605 may be a mobile node, and the type of service may indicate the mobility capabilities of node 605. Furthermore, access layer (AS) security may be established between node 605 and central unit 620-a, thereby securing radio resource control signaling.

[0138] At 665, distributed unit 565 can reselect the central unit based on the service type associated with node 605. For example, distributed unit 615 can select central unit 620-b based on the fact that node 605 is a mobile node. At 670, node 605 and donor node 610 (e.g., central units 620-a and 620-b) can participate in a handover procedure that is viewed as an intra-cell handover from node 605's perspective. During the handover procedure, a second RRC connection can be established between node 605 and central unit 620-b, and context information associated with node 605 (e.g., security key) can be passed from central unit 620-a to central unit 620-b (e.g., via an inter-CU tunnel). In some examples, distributed unit 615 can trigger the handover procedure by sending respective handover requests to central units 620-a and 620-b. Therefore, a second RRC connection can be established between node 605 and central unit 620-b, and central unit 620-b can obtain context information associated with node 605.

[0139] After establishing an RRC connection with the central unit 620-b, the distributed unit 615 can relay messages between node 605, the central unit 620-b, and the core network, enabling relevant devices to perform a second (e.g., later) phase of the integration procedure at 675. The later phase of the integration procedure may include authentication procedures, RLC channel establishment and / or F1 channel establishment, and other sub-procedures.

[0140] Therefore, donor node 510 can assist node 605 in connecting to central unit 620-b (instead of central unit 620-a) so that when a handover procedure occurs between donor nodes, the context information of the UE served by node 605 is present at central unit 620-b. Although described with reference to an RRC connection, the techniques described herein can be implemented for other types of connections. Alternative examples of process flow 600 can be implemented, in which some operations are performed in a different order than described, in parallel, or not at all. In some cases, each operation may include additional features not mentioned below, or further operations may be added. Additionally, some operations may be performed multiple times, or combinations of operations may be repeated or cyclical.

[0141] In some examples, aspects of the techniques described herein can be modified to be compatible with other types of networks, such as networks that do not support mobile IAB nodes or networks that support various types of nodes, such as legacy networks. In a first example related to registration, if the service type indicates a mobile IAB node, the donor node can select a CU from a cloud IAB radio access network (RAN) dedicated to IAB. In this scenario, an interface to the cloud IAB RAN can be pre-configured at the donor node, N2 can be moved from the donor node to the cloud CU, and the IAB RAN topology can be transparent from the perspective of other donor nodes (e.g., the donor node CU can be regarded as a single donor node CU by other donor nodes). Additionally, the donor node serving the mobile node can assume the DU role for that mobile node (e.g., the donor node can relay Uu and F1 communication between the node and the cloud CU). If the IP address of the node or donor node changes, a new F1 interface can be established (or a proprietary process can be used to avoid establishing a new FI interface).

[0142] In a second example relating to IAB node handover from a legacy donor node (e.g., a donor node that does not support mobile nodes) to a non-legacy donor node (e.g., a donor node that supports mobile nodes), the target donor node may interact with the cloud CU to construct a handover command (e.g., the handover procedure may be tunneled to the cloud CU). In a third example relating to IAB node handover from a non-legacy donor node to a legacy donor node, the cloud CU may perform a normal handover procedure with the node and UE connected via the IAB node based on the fact that the legacy donor node does not support mobile nodes.

[0143] Although some aspects of this disclosure have been described with reference to IAB networks and related devices or nodes, the techniques, processes, operations, methods and devices described herein are more broadly applicable to a wide range of networks, devices and nodes in various wireless communication environments, and this disclosure should not be construed as limiting unless otherwise specifically indicated.

[0144] Figure 7 A block diagram 700 of a device 705 supporting unit selection for a node, according to various aspects of this disclosure, is shown. Device 705 may be an example of various aspects of UE 115 as described herein. Device 705 may include a receiver 710, a communication manager 715, and a transmitter 720. Device 705 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0145] Receiver 710 can receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to node selection). This information can be transmitted to other components of device 705. Receiver 710 can be a reference... Figure 10 Examples of various aspects of the transceiver 1020 described. The receiver 710 may utilize a single antenna or a set of antennas.

[0146] The communication manager 715 can determine the service type of a first node, which indicates that the first node is a mobile node; transmit an indication of the service type of the first node to a second node during a random access procedure; and establish a connection with the unit of the second node based on the indication of the service type transmitted during the random access procedure, for serving nodes in the wireless network associated with that service type. The communication manager 715 may be an example of various aspects of the communication manager 1010 described herein.

[0147] The communication manager 715 or its sub-components may be implemented in hardware, code executed by a processor (e.g., software or firmware), or any combination thereof. If implemented in code executed by a processor, the functionality of the communication manager 715 or its sub-components may be performed by a general-purpose processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof, designed to perform the functions described in this disclosure.

[0148] The communication manager 715 or its subcomponents may be physically located at various locations, including being distributed such that portions of the functionality are implemented by one or more physical components at different physical locations. In some examples, according to various aspects of this disclosure, the communication manager 715 or its subcomponents may be separate and distinct components. In some examples, according to various aspects of this disclosure, the communication manager 715 or its subcomponents may be combined with one or more other hardware components, including but not limited to input / output (I / O) components, transceivers, network servers, another computing device, one or more other components described in this disclosure, or combinations thereof.

[0149] Transmitter 720 can transmit signals generated by other components of device 705. In some examples, transmitter 720 may coexist with receiver 710 in a transceiver module. For example, transmitter 720 may be a reference... Figure 10 Examples of various aspects of the transceiver 1020 described. The transmitter 720 may utilize a single antenna or an antenna set.

[0150] Figure 8A block diagram 800 of a device 805 supporting unit selection for a node according to various aspects of this disclosure is shown. Device 805 may be an example of a device 705 or a aspect of UE 115 as described herein. Device 805 may include a receiver 810, a communication manager 815, and a transmitter 835. Device 805 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0151] Receiver 810 can receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to node selection). This information can be transmitted to other components of device 805. Receiver 810 can be a reference... Figure 10 Examples of various aspects of the transceiver 1020 described herein. The receiver 810 may utilize a single antenna or a set of antennas.

[0152] Communication manager 815 may be an example of aspects of communication manager 715 as described herein. Communication manager 815 may include service type module 820, transmission module 825, and connection module 830. Communication manager 815 may be an example of aspects of communication manager 1010 as described herein.

[0153] The service type module 820 can determine the service type of the first node, which indicates that the first node is a mobile node. The transmission module 825 can transmit the indication of the service type of the first node to the second node during the random access procedure. The connection module 830 can establish a connection with the unit of the second node based on the indication of the service type transmitted during the random access procedure, for serving nodes in the wireless network associated with that service type.

[0154] Transmitter 835 can transmit signals generated by other components of device 805. In some examples, transmitter 835 may coexist with receiver 810 in a transceiver module. For example, transmitter 835 may be a reference... Figure 10 Examples of various aspects of the transceiver 1020 described. The transmitter 835 may utilize a single antenna or an antenna set.

[0155] Figure 9A block diagram 900 of a communication manager 905 supporting unit selection for nodes according to various aspects of this disclosure is shown. The communication manager 905 may be an example of aspects of the communication manager 715, communication manager 815, or communication manager 1010 described herein. The communication manager 905 may include a service type module 910, a transmission module 915, a connection module 920, a random access module 925, and a receiving module 930. Each of these modules may communicate directly or indirectly with each other (e.g., via one or more buses).

[0156] Service type module 910 can determine the service type of the first node, which indicates that the first node is a mobile node. Transmission module 915 can transmit an indication of the service type of the first node to the second node during random access procedures. Connection module 920 can establish a connection with a unit of the second node based on the indication of the service type transmitted during random access procedures, for servicing nodes in the wireless network associated with that service type. In some cases, the service type indicates the mobility capability of the first node, and the connection is an RRC connection. In some cases, the first node includes a relay node, the second node includes a donor node, and the unit includes a central unit of the donor node, which is shared among the set of nodes including the second node.

[0157] In some examples, transmitting an indication of the type of service includes including the indication of the type of service in the request to establish a connection with the second node. In some cases, this request includes message 3 of the random access procedure or message A of the random access procedure.

[0158] In some examples, transmitting an indication of the type of service includes transmitting the indication of the type of service in the acknowledgment message of the random access procedure. In some cases, the acknowledgment message includes message 5 of the random access procedure. In some examples, the transmission request includes transmitting a first portion of the identifier of the first node. In some examples, the transmission module 915 may transmit a second portion of the identifier in message 5 of the random access procedure.

[0159] The random access module 925 can transmit a random access preamble on a random access channel resource set dedicated to nodes associated with the service type. The receiving module 930 can receive from the second node a system information block indicating that the random access channel resource set is dedicated to nodes associated with the service type.

[0160] Figure 10A diagram of a system 1000 including device 1005 supporting node selection according to various aspects of this disclosure is shown. Device 1005 may be an example of device 705, device 805, or UE 115 as described herein, or a component including the aforementioned devices. Device 1005 may include components for bidirectional voice and data communication, including components for transmitting and receiving communications, including a communication manager 1010, an I / O controller 1015, a transceiver 1020, an antenna 1025, a memory 1030, and a processor 1040. These components may be in electronic communication via one or more buses (e.g., bus 1045).

[0161] The communication manager 1010 can determine the service type of the first node, which indicates that the first node is a mobile node; transmit an indication of the service type of the first node to the second node during a random access procedure; and establish a connection with the unit of the second node based on the indication of the service type transmitted during the random access procedure, so as to serve the node in the wireless network associated with the service type.

[0162] I / O controller 1015 manages the input and output signals of device 1005. I / O controller 1015 can also manage peripheral devices not integrated into device 1005. In some cases, I / O controller 1015 may represent a physical connection or port to an external peripheral device. In some cases, I / O controller 1015 may utilize an operating system, such as... Or another known operating system. In other cases, the I / O controller 1015 may represent or interact with a modem, keyboard, mouse, touchscreen, or similar device. In some cases, the I / O controller 1015 may be implemented as part of a processor. In some cases, a user may interact with the device 1005 via the I / O controller 1015 or via hardware components controlled by the I / O controller 1015.

[0163] Transceiver 1020 can communicate bidirectionally via one or more antennas, wired or wireless links, as described above. For example, transceiver 1020 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. Transceiver 1020 may also include a modem to modulate packets and provide the modulated packets to the antenna for transmission, and to demodulate packets received from the antenna.

[0164] In some cases, the wireless device may include a single antenna 1025. However, in other cases, the device may have more than one antenna 1025, which may be able to transmit or receive multiple wireless transmissions concurrently.

[0165] Memory 1030 may include RAM and ROM. Memory 1030 may store computer-readable, computer-executable code 1035, including instructions that, when executed, cause the processor to perform the various functions described herein. In some cases, memory 1030 may particularly include a BIOS that controls basic hardware or software operations, such as interaction with peripheral components or devices.

[0166] Processor 1040 may include intelligent hardware devices (e.g., general-purpose processors, DSPs, CPUs, microcontrollers, ASICs, FPGAs, programmable logic devices, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, processor 1040 may be configured to use a memory controller to operate a memory array. In other cases, the memory controller may be integrated into processor 1040. Processor 1040 may be configured to execute computer-readable instructions stored in memory (e.g., memory 1030) to cause device 1005 to perform various functions (e.g., supporting functions or tasks for node cell selection).

[0167] Code 1035 may include instructions for implementing various aspects of this disclosure, including instructions for supporting wireless communication. Code 1035 may be stored in a non-transient computer-readable medium, such as system memory or other types of memory. In some cases, code 1035 may not be directly executed by processor 1040, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0168] Figure 11 A block diagram 1100 of a device 1105 supporting unit selection for nodes according to various aspects of this disclosure is shown. Device 1105 may be an example of various aspects of base station 105 as described herein. Device 1105 may include a receiver 1110, a communication manager 1115, and a transmitter 1120. Device 1105 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0169] Receiver 1110 can receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to node selection). This information can be transmitted to other components of device 1105. Receiver 1110 can be a reference... Figure 14 Examples of various aspects of the transceiver 1420 described. The receiver 1110 may utilize a single antenna or an antenna set.

[0170] Communication manager 1115 may receive an indication of the service type of a second node, which indicates that the second node is a mobile node; determine a second unit of the first node based on the service type of the second node to establish a connection with the second node, the second unit being used to serve nodes associated with the service type and being a unit in the first node's unit set; and based on this determination, transmit a request to establish a connection to the second unit used to serve nodes associated with the service type. Communication manager 1115 may be an example of aspects of communication manager 1410 described herein.

[0171] The communication manager 1115 or its sub-components may be implemented in hardware, processor-executable code (e.g., software or firmware), or any combination thereof. If implemented in processor-executable code, the functionality of the communication manager 1115 or its sub-components may be performed by a general-purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in this disclosure.

[0172] The communication manager 1115 or its subcomponents may be physically located at various locations, including being distributed such that portions of the functionality are implemented by one or more physical components at different physical locations. In some examples, according to various aspects of this disclosure, the communication manager 1115 or its subcomponents may be separate and distinct components. In some examples, according to various aspects of this disclosure, the communication manager 1115 or its subcomponents may be combined with one or more other hardware components (including, but not limited to, I / O components, transceivers, network servers, another computing device, one or more other components described in this disclosure, or combinations thereof).

[0173] Transmitter 1120 can transmit signals generated by other components of device 1105. In some examples, transmitter 1120 may coexist with receiver 1110 in a transceiver module. For example, transmitter 1120 may be a reference... Figure 14 Examples of various aspects of the transceiver 1420 described. The transmitter 1120 may utilize a single antenna or an antenna set.

[0174] Figure 12 A block diagram 1200 is shown of a device 1205 supporting unit selection for nodes according to various aspects of this disclosure. Device 1205 may be an example of aspects of device 1105 or base station 105 as described herein. Device 1205 may include a receiver 1210, a communication manager 1215, and a transmitter 1235. Device 1205 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0175] Receiver 1210 can receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to node selection). This information can be transmitted to other components of device 1205. Receiver 1210 can be a reference... Figure 14 Examples of various aspects of the transceiver 1420 described. The receiver 1210 may utilize a single antenna or an antenna set.

[0176] Communication manager 1215 may be an example of aspects of communication manager 1115 as described herein. Communication manager 1215 may include service type module 1220, selection module 1225, and transport module 1230. Communication manager 1215 may be an example of aspects of communication manager 1410 as described herein.

[0177] Service type module 1220 can receive an indication of the service type of the second node, which indicates that the second node is a mobile node. Selection module 1225 can determine a second unit of the first node to establish a connection with the second node based on the service type of the second node. This second unit is used to serve nodes associated with the service type and is one of the units in the first node's unit set. Transmission module 1230 can transmit a connection establishment request to the second unit used to serve nodes associated with the service type based on this determination.

[0178] Transmitter 1235 can transmit signals generated by other components of device 1205. In some examples, transmitter 1235 may coexist with receiver 1210 in a transceiver module. For example, transmitter 1235 may be a reference... Figure 14 Examples of various aspects of the transceiver 1420 are described. The transmitter 1235 may utilize a single antenna or an antenna set.

[0179] Figure 13 A block diagram 1300 of a communication manager 1305 supporting unit selection for nodes according to various aspects of this disclosure is shown. The communication manager 1305 may be an example of aspects of the communication manager 1115, communication manager 1215, or communication manager 1410 described herein. The communication manager 1305 may include a service type module 1310, a selection module 1315, a transmission module 1320, a receiving module 1325, a system information module 1330, a request module 1335, a connection module 1340, a switching module 1345, and a random access module 1350. Each of these modules may communicate directly or indirectly with each other (e.g., via one or more buses).

[0180] Service type module 1310 can receive an indication of the service type of the second node, which indicates that the second node is a mobile node. Selection module 1315 can determine a second unit of the first node to establish a connection with the second node based on the service type of the second node. This second unit is used to serve nodes associated with the service type and is one of the units in the first node's unit set. Transmission module 1320 can transmit a connection establishment request to the second unit used to serve nodes associated with the service type based on this determination.

[0181] Request module 1335 may receive a request from a second node to establish radio resource control connectivity with the first node. In some examples, selection module 1315 may select a third unit to establish a first connection with the second node based on the request. In some cases, the second unit of the first node is separate from the first unit of the first node, and the set of units includes a third unit for serving nodes associated with a second service type, which is co-located with the first unit, and wherein the second unit is shared among the set of nodes including the first node.

[0182] In some examples, the transmission module 1320 may transmit a request to the second unit for a node associated with a service and service type, the request including an indication of the service type of the second node. In some examples, the transmission module 1320 may transmit an indication of the service type of the second node to the core network based on the establishment of a connection between the second node and the second unit for a node associated with a service and service type.

[0183] In some examples, the transmission module 1320 may transmit a request to establish a second connection to the second unit based on the service type of the second node. The receiving module 1325 may receive an indication of the service type, which may be included in the request from the second node to establish a connection with the first node. In some examples, the request from the second node may include or indicate a first portion of an identifier for the second node. In some examples, the receiving module 1325 may receive a second portion of the identifier in message 5 of the random access procedure.

[0184] In some examples, receiving module 1325 may receive confirmation from the core network that the second node has the indicated service type.

[0185] In some examples, receiving module 1325 may receive a message from the second node acknowledging that a first connection has been established with a third unit of the first node for serving nodes associated with a second service type, wherein the message includes an indication of the service type of the second node. In some examples, transmitting module 1320 may transmit an instruction to release the first connection with the second node to the third unit for serving nodes associated with the second service type, based on the service type of the second node, wherein the second connection was established based on the instruction to release the first connection.

[0186] In some cases, the request from the second node includes message 3 or message A of the random access procedure. In some cases, the acknowledgment message includes message 5 of the random access procedure. In some cases, an indication of the service type is received from the core network during the registration procedure with the second node.

[0187] The system information module 1330 can receive an indication of the service type, which includes receiving the indication of the service type in an acknowledgment message from the second node, and the acknowledgment message portion of the random access procedure is used to establish a connection with the first node.

[0188] In some examples, system information module 1330 may transmit a system information block to a second node, the system information block indicating a set of random access channel resources dedicated to nodes associated with the service type. Random access module 1350 may receive a random access preamble on the set of random access channel resources dedicated to nodes associated with the service type.

[0189] Connection module 1340 can determine that a first connection has been established between a second node and a third unit of the first node for serving a node associated with a second service type. Switching module 1345 can transmit a switching command to the third unit based on the service type of the second node, wherein the second connection is established based on the switching command.

[0190] Figure 14 A diagram of a system 1400 including device 1405 supporting unit selection for nodes, according to various aspects of this disclosure, is shown. Device 1405 may be an example of device 1105, device 1205, or base station 105 as described herein, or a component including such devices. Device 1405 may include components for bidirectional voice and data communication, including components for transmitting and receiving communications, including a communication manager 1410, a network communication manager 1415, a transceiver 1420, an antenna 1425, a memory 1430, a processor 1440, and an inter-station communication manager 1445. These components may be in electronic communication via one or more buses (e.g., bus 1450).

[0191] The communication manager 1410 may receive an indication of the service type of a second node, which indicates that the second node is a mobile node; determine a second unit of the first node based on the service type of the second node to establish a connection with the second node, the second unit being used to serve the node associated with the service type and being a unit in the unit set of the first node; and based on the determination, transmit a request to establish a connection to the second unit used to serve the node associated with the service type.

[0192] The network communication manager 1415 can manage communication with the core network (e.g., via one or more wired backhaul links). For example, the network communication manager 1415 can manage the delivery of data communication by client devices (such as one or more UEs 115).

[0193] Transceiver 1420 can communicate bidirectionally via one or more antennas, wired or wireless links, as described above. For example, transceiver 1420 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. Transceiver 1420 may also include a modem to modulate packets and provide the modulated packets to the antenna for transmission, and to demodulate packets received from the antenna.

[0194] In some cases, the wireless device may include a single antenna 1425. However, in other cases, the device may have more than one antenna 1425, which may be able to transmit or receive multiple wireless transmissions concurrently.

[0195] Memory 1430 may include RAM, ROM, or a combination thereof. Memory 1430 may store computer-readable code 1435 including instructions that, when executed by a processor (e.g., processor 1440), cause the device to perform the various functions described herein. In some cases, memory 1430 may particularly include a BIOS that controls basic hardware or software operation, such as interaction with peripheral components or devices.

[0196] Processor 1440 may include intelligent hardware devices (e.g., general-purpose processors, DSPs, CPUs, microcontrollers, ASICs, FPGAs, programmable logic devices, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, processor 1440 may be configured to use a memory controller to operate a memory array. In some cases, the memory controller may be integrated into processor 1440. Processor 1440 may be configured to execute computer-readable instructions stored in memory (e.g., memory 1430) to cause device 1405 to perform various functions (e.g., supporting various functions or tasks for node cell selection).

[0197] Inter-site communication manager 1445 manages communication with other base stations 105 and may include a controller or scheduler for cooperating with other base stations 105 to control communication with UE 115. For example, inter-site communication manager 1445 may coordinate the scheduling of transmissions to UE 115 for various interference mitigation techniques, such as beamforming or joint transmission. In some examples, inter-site communication manager 1445 may provide an X2 interface within LTE / LTE-A wireless communication network technology to facilitate communication between base stations 105.

[0198] Code 1435 may include instructions for implementing various aspects of this disclosure, including instructions for supporting wireless communication. Code 1435 may be stored in a non-transient computer-readable medium, such as system memory or other types of memory. In some cases, code 1435 may not be directly executed by processor 1440, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0199] Figure 15 A flowchart illustrating a method 1500 for supporting node cell selection according to various aspects of this disclosure is shown. The operation of method 1500 can be implemented by a node or its components as described herein. For example, the operation of method 1500 can be implemented by, as referred to... Figures 7 to 10 The described communication manager is used to execute this. In some examples, the node can execute a set of instructions to control the node's functional elements to perform the functions described below. Additionally or alternatively, the node can use dedicated hardware to perform aspects of the functions described below.

[0200] At point 1505, the method may include determining the service type of the first node. In some examples, the service type indicates that the first node is a mobile node. The operation at point 1505 may be performed according to the methods described herein. In some examples, aspects of the operation at point 1505 may be determined by reference to... Figures 7 to 10 The described service type module is used for execution.

[0201] At point 1510, the method may transmit an indication of the type of service for the first node to the second node during the random access procedure. The operation of point 1510 may be performed according to the method described herein. In some examples, aspects of the operation of point 1510 may be derived from, as referenced... Figures 7 to 10 The described transmission module is used to execute this.

[0202] At 1515, the method may establish a connection with a unit of the second node for serving nodes in the wireless network associated with the service type, based at least in part on an indication of the service type transmitted during the random access procedure. The operation of 1515 may be performed according to the method described herein. In some examples, aspects of the operation of 1515 may be derived from, as referenced... Figures 7 to 10 The described connection module is used for execution.

[0203] Figure 16 A flowchart illustrating a method 1600 for supporting node cell selection according to various aspects of this disclosure is shown. The operation of method 1600 can be implemented by a donor node or its components as described herein. For example, the operation of method 1600 can be implemented by, as referred to... Figures 11 to 14 The described communication manager is used to perform this. In some examples, the donor node can execute a set of instructions to control the functional elements of the donor node to perform the functions described below. Additionally or alternatively, the donor node can use dedicated hardware to perform aspects of the functions described below.

[0204] At point 1605, the method may receive an indication of the service type of the second node, which indicates that the second node is a mobile node. The operation of point 1605 may be performed according to the method described herein. In some examples, aspects of the operation of point 1605 may be determined by reference to... Figures 11 to 14 The described service type module is used for execution.

[0205] At 1610, the method may determine a second unit of the first node for establishing a connection with the second node based at least in part on the service type of the second node. This second unit is for serving nodes associated with the service type and is one of multiple units of the first node. The operation of 1610 may be performed according to the method described herein. In some examples, aspects of the operation of 1610 may be derived from, as referenced... Figures 11 to 14 The described selection module is used for execution.

[0206] At point 1615, the method may, at least in part, transmit a request to establish a connection to a second unit for a node associated with a service type, based on this determination. The operation at 1615 may be performed according to the method described herein. In some examples, aspects of the operation at 1615 may be determined by, as referenced... Figures 11 to 14 The described transmission module is used to execute this.

[0207] It should be noted that the methods described in this paper describe possible implementations, and the operations and features can be rearranged or otherwise modified, and other implementations are also possible. Furthermore, aspects from two or more methods can be combined.

[0208] While aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for illustrative purposes, and the terms LTE, LTE-A, LTE-A Pro, or NR may be used in most of the description, the techniques described herein can also be applied to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques can be applied to a variety of other wireless communication systems, such as Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0209] The information and signals described herein can be represented using any of a wide variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout this description can be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or light particles, or any combination thereof.

[0210] The various illustrative boxes and components described herein can be implemented or executed using a general-purpose processor, DSP, ASIC, CPU, FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general-purpose processor may be a microprocessor, but in alternatives, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors working in conjunction with a DSP core, or any other such configuration).

[0211] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored or transmitted as one or more instructions or code on a computer-readable medium. Other examples and implementations fall within the scope of this disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwired, or any combination thereof. Features implementing the functions may also be physically located in various locations, including being distributed such that different parts of the function are implemented at different physical locations.

[0212] Computer-readable media includes both non-transient computer storage media and communication media, encompassing any medium that facilitates the transfer of a computer program from one location to another. Non-transient storage media can be any available medium accessible to a general-purpose or special-purpose computer. By way of example, and not limitation, non-transient computer-readable media may include RAM, ROM, electrically erasable programmable read-only memory (EEPROM), compact disc (CD) ROM or other optical disc storage, magnetic disk storage or other magnetic storage devices, or any other non-transient medium that can be used to carry or store desired program code in the form of instructions or data structures and is accessible to a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Similarly, any connection is also legitimately referred to as computer-readable media. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then that coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of media. As used in this article, disk and disc include CDs, laser discs, optical discs, DVDs, floppy disks, and Blu-ray discs, where disks often magnetically reproduce data while discs optically reproduce data using lasers. Combinations of these media are also included within the scope of computer-readable media.

[0213] As used herein (including in the claims), the word "or" in an enumeration of items (e.g., an enumeration of items accompanied by phrases such as "at least one of" or "one or more of") indicates an inclusive enumeration, such that an enumeration of at least one of, for example, A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Similarly, as used herein, the phrase "based on" should not be interpreted as referring to a closed set of conditions. For example, an example step described as "based on condition A" may be based on both condition A and condition B without departing from the scope of this disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "at least partially based on".

[0214] In the accompanying drawings, similar components or features may have the same reference numerals. Furthermore, components of the same type may be distinguished by a dash following the reference numeral and a second reference numeral used to differentiate between similar components. If only the first reference numeral is used in the description, the description may apply to any of the similar components having the same first reference numeral, regardless of the second reference numeral or other subsequent reference numerals.

[0215] The descriptions herein, illustrated with reference to the accompanying drawings, depict exemplary configurations and are not representative of all examples that may be implemented or fall within the scope of the claims. The term "example" as used herein means "serving as an example, instance, or illustration" and does not imply "superior" or "outperforming" other examples. This detailed description includes specific details to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0216] The description provided herein is intended to enable those skilled in the art to make or use this disclosure. Various modifications to this disclosure will be apparent to those skilled in the art, and the universal principles defined herein can be applied to other variations without departing from the scope of this disclosure. Therefore, this disclosure is not limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for performing wireless communication at a first node in a wireless network, the method comprising: Determine the service type of the first node, wherein the service type indicates the mobility capability of the first node; During the random access procedure, an indication of the service type for the first node is transmitted to a second node associated with a plurality of units, wherein the plurality of units includes a first unit dedicated to nodes associated with the service type and a second unit dedicated to nodes not associated with the service type; as well as A connection is established with the first unit of the plurality of units of the second node that is dedicated to the node associated with the service type, based at least in part on the indication of the service type transmitted to the first node during the random access procedure.

2. The method of claim 1, wherein transmitting an indication of the service type comprises: The request to establish the connection with the second node includes an indication of the service type.

3. The method of claim 2, wherein the request includes message 3 of the random access procedure or message A of the random access procedure.

4. The method of claim 2, wherein transmitting the request includes transmitting a first portion of the identifier of the first node, the method further comprising: The second part of the identifier is transmitted in message 5 of the random access procedure.

5. The method of claim 1, wherein transmitting an indication of the service type comprises: The confirmation message of the random access procedure transmits an indication of the service type.

6. The method of claim 5, wherein the confirmation message includes message 5 of the random access procedure.

7. The method of claim 1, wherein transmitting an indication of the service type comprises: Transmit random access preambles on a set of random access channel resources dedicated to nodes associated with the service type.

8. The method of claim 7, further comprising: Receive from the second node a system information block indicating that the random access channel resource set is dedicated to the node associated with the service type.

9. The method of claim 1, wherein the first node includes a relay node, the second node includes a donor node, and the first unit includes a central unit of the donor node, the central unit being shared among a plurality of nodes including the second node.

10. The method of claim 1, wherein the service type indicates the mobility capability of the first node, and the connection includes a radio resource control connection.

11. The method of claim 1, wherein the first node comprises a user equipment (UE).

12. A method for performing wireless communication at a first unit of a first node in a wireless network, comprising: Receive an indication of the service type for the second node, the service type indicating that the second node is a mobile node; The second unit of the first node is determined at least in part based on the service type of the second node to establish a connection with the second node. The second unit is used to serve nodes associated with the service type and is one of a plurality of units of the first node. as well as The request to establish the connection is transmitted to the second unit, which is used to serve the node associated with the service type, based at least in part on the determination.

13. The method of claim 12, wherein receiving an indication of the service type comprises: The service type is indicated in the request from the second node to establish the connection with the first node.

14. The method of claim 13, wherein the request from the second node includes random access procedure message 3 or random access procedure message A.

15. The method of claim 13, wherein the request from the second node includes a first portion of the identifier of the second node, the method further comprising: The second part of the identifier is received in message 5 of the random access procedure.

16. The method of claim 12, wherein transmitting the request comprises: The request is transmitted to the second unit, which serves a node associated with the service type, and the request includes an indication of the service type of the second node.

17. The method of claim 12, further comprising: The indication of the service type of the second node is transmitted to the core network, at least in part, based on the connection established between the second node and the second unit for serving nodes associated with the service type. as well as Receive confirmation from the core network that the second node has the indicated service type.

18. The method of claim 12, wherein receiving an indication of the service type comprises: The confirmation message from the second node receives an indication of the service type, and a portion of the confirmation message of the random access procedure is used to establish the connection with the first node.

19. The method of claim 18, wherein the confirmation message includes message 5 of the random access procedure.

20. The method of claim 12, wherein the connection with the second unit includes a second connection, the method further comprising: Receive a message from the second node confirming that a first connection has been established with a third unit of the first node for a node associated with a second service type, wherein the message includes an indication of the service type of the second node; and The instruction to release the first connection with the second node is transmitted to the third unit for serving nodes associated with the second service type, at least in part based on the service type of the second node, wherein the second connection is established at least in part based on the instruction to release the first connection.

21. The method of claim 20, further comprising: The request to establish the second connection is transmitted to the second unit based at least in part on the service type of the second node.

22. The method of claim 20, further comprising: Receive a request from the second node to establish radio resource control connectivity with the first node; as well as The third unit is selected at least in part based on the request to establish the first connection with the second node.

23. The method of claim 12, wherein the indication of the service type is received from the core network during the registration procedure with the second node.

24. The method of claim 12, wherein the connection with the second unit includes a second connection, the method further comprising: It is determined that a first connection has been established between the second node and a third unit of the first node that is associated with the second service type. as well as The switching command is transmitted to the third unit at least in part based on the service type of the second node, wherein the second connection is established at least in part based on the switching command.

25. The method of claim 12, wherein receiving the indication of the service type for the second node comprises: Receive random access preamble on a set of random access channel resources dedicated to nodes associated with the service type.

26. The method of claim 25, further comprising: A system information block indicating that the random access channel resource set is dedicated to the node associated with the service type is transmitted to the second node.

27. The method of claim 12, wherein the second unit of the first node is separate from the first unit of the first node, and the plurality of units include a third unit for serving a node associated with a second service type, the third unit being co-located with the first unit, and wherein the second unit is shared among the plurality of nodes including the first node.

28. An apparatus for performing wireless communication at a first node of a wireless network, comprising: processor, A memory coupled to the processor, wherein the memory includes instructions executable by the processor to cause the device to: Determine the service type of the first node, wherein the service type indicates the mobility capability of the first node; During the random access procedure, an indication of the service type for the first node is transmitted to a second node associated with a plurality of units, wherein the plurality of units includes a first unit dedicated to nodes associated with the service type and a second unit dedicated to nodes not associated with the service type; as well as A connection is established with the first unit of the plurality of units of the second node that is dedicated to the node associated with the service type, based at least in part on the indication of the service type transmitted to the first node during the random access procedure.

29. An apparatus for performing wireless communication at a first node of a wireless network, comprising: processor, A memory coupled to the processor, wherein the memory includes instructions executable by the processor to cause the device to perform the method as claimed in any one of claims 2-11.

30. An apparatus for wireless communication at a first unit of a first node, comprising: processor, A memory coupled to the processor, wherein the memory includes instructions executable by the processor to cause the device to: Receive an indication of the service type for the second node, the service type indicating that the second node is a mobile node; The second unit of the first node is determined at least in part based on the service type of the second node to establish a connection with the second node. The second unit is used to serve nodes associated with the service type and is one of a plurality of units of the first node. as well as The request to establish the connection is transmitted to the second unit, which is used to serve the node associated with the service type, based at least in part on the determination.

31. An apparatus for wireless communication at a first unit of a first node, comprising: processor, A memory coupled to the processor, wherein the memory includes instructions executable by the processor to cause the device to perform the method of any one of claims 13-27.

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