This Nonprovisional application claims priority under 35 U.S.C. § 119 on provisional Application No. 62,988,246 on Mar. 11, 2020, the entire contents of which are hereby incorporated by reference.
The technology relates to wireless communications, and particularly to radio architecture and operation a wireless relay network.
A radio access network typically resides between wireless devices, such as user equipment (UEs), mobile phones, mobile stations, or any other device having wireless termination, and a core network. Example of radio access network types includes the GRAN, GSM radio access network; the GERAN, which includes EDGE packet radio services; UTRAN, the UMTS radio access network; E-UTRAN, which includes Long-Term Evolution; and g-UTRAN, the New Radio (NR).
A radio access network may comprise one or more access nodes, such as base station nodes, which facilitate wireless communication or otherwise provides an interface between a wireless terminal and a telecommunications system. A non-limiting example of a base station can include, depending on radio access technology type, a Node B (“NB”), an enhanced Node B (“eNB”), a home eNB (“HeNB”), a gNB (for a New Radio [“NR”] technology system), or some other similar terminology.
The 3rd Generation Partnership Project (“3GPP”) is a group that, e.g., develops collaboration agreements such as 3GPP standards that aim to define globally applicable technical specifications and technical reports for wireless communication systems. Various 3GPP documents may describe certain aspects of radio access networks. Overall architecture for a fifth generation system, e.g., the 5G System, also called “NR” or “New Radio”, as well as “NG” or “Next Generation”, is shown in
In some cellular mobile communication systems and networks, such as Long-Term Evolution (LTE) and New Radio (NR), a service area is covered by one or more base stations, where each of such base stations may be connected to a core network by fixed-line backhaul links (e.g., optical fiber cables). In some instances, due to weak signals from the base station at the edge of the service area, users tend to experience performance issues, such as: reduced data rates, high probability of link failures, etc. A relay node concept has been introduced to expand the coverage area and increase the signal quality. As implemented, the relay node may be connected to the base station using a wireless backhaul link.
In 3rd Generation Partnership Project (3GPP), the relay node concept for the fifth generation (5G) cellular system has been discussed and standardized, where the relay nodes may utilize the same 5G radio access technologies (e.g., New Radio (NR)) for the operation of services to User Equipment (UE) (access link) and connections to the core network (backhaul link) simultaneously. These radio links may be multiplexed in time, frequency, and/or space. This system may be referred to as Integrated Access and Backhaul (IAB).
Some such cellular mobile communication systems and networks may comprise IAB-donors and IAB-nodes, where an IAB-donor may provide interface to a core network to UEs and wireless backhauling functionality to IAB-nodes; and additionally, an IAB-node may provide IAB functionality combined with wireless self-backhauling capabilities. IAB-nodes may need to periodically perform inter-IAB-node discovery to detect new IAB-nodes in their vicinity based on cell-specific reference signals (e.g., Synchronization Signal and PBCH block SSB). The cell-specific reference signals may be broadcasted on a Physical Broadcast Channel (PBCH) where packets may be carried or broadcasted on the Master Information Block (MIB) section.
A node in an IAB-based relay network may utilize resources provided by other nodes. It is expected that in some circumstances a portion of the relay network may get congested and therefore some nodes may desire to control use of their resources from others. What is needed, therefore, are apparatus, methods and procedures to handle such a congestion via access restrictions, e.g., access barring or cell barring.
Moreover, an IAB-based relay network may use broadcast signals to convey essential information.
What is also needed, therefore, are apparatus, methods, and procedures to notify nodes and terminals of an IAB-based relay network when some contents of the essential information change and when to implement those changes.
In one example, an integrated access and backhaul (IAB) node comprising a first radio interface and a second radio interface, the first radio interface being configured to establish a connection with a donor node, the second radio interface being configured to serve a cell to communicate with a wireless terminal, the IAB node comprising: processor circuitry configured to: detect a radio link failure (RLF) at the first radio interface; generate, based on the RLF, system information comprising at least one cell status indication indicating that the cell is barred and; generate, based on the at least one cell status indication, a notification message comprising notification information configured to instruct the wireless terminal to initiate a system information acquisition procedure immediately; transmitter circuitry configured to transmit, using the second interface, to the wireless terminal: the notification message; and, the system information.
In one example, a wireless terminal that communicates with an integrated access and backhaul (IAB) node via a cell served by the IAB node, the wireless terminal comprising: receiver circuitry configured to receive a notification message comprising notification information, the notification information instructing to initiate a system information acquisition procedure immediately; processor circuitry configured to initiate, based on the notification information, the system information acquisition procedure to acquire system information, the system information comprising at least one cell status indication indicating whether or not the cell is barred, wherein; in a case that the at least cell status indicates that the cell is barred, a cell selection procedure is initiated.
In one example, a method for an integrated access and backhaul (IAB) node comprising a first radio interface and a second radio interface, the first radio interface being configured to establish a connection with a donor node, the second radio interface being configured to serve a cell to communicate with a wireless terminal, the method comprising: detecting a radio link failure (RLF) at the first radio interface; generating, based on the RLF, system information comprising at least one cell status indication indicating that the cell is barred and; generating, based on the at least one cell status indication, a notification message comprising notification information configured to instruct the wireless terminal to initiate a system information acquisition procedure immediately; transmitting, using the second interface, to the wireless terminal: the notification message; and, the system information.
In one example, a method for a wireless terminal that communicate with an integrated access and backhaul (IAB) node, the method comprising: receiving a notification message comprises notification information, the notification information instructing to initiate a system information acquisition procedure immediately; initiating, based on the notification information, a system information acquisition procedure to acquire system information, the system information comprising at least one cell status indication indicating whether or not the cell is barred, wherein; in a case that the at least cell status indicates that the cell is barred, a cell selection procedure is initiated.
The foregoing and other objects, features, and advantages of the technology disclosed herein will be apparent from the following more particular description of preferred embodiments as illustrated in the accompanying drawings in which reference characters refer to the same parts throughout the various views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the technology disclosed herein.
In one of its example aspects the technology disclosed herein concerns an integrated access and backhaul (IAB) parent node which comprises a first radio interface and a radio second interface. The first radio interface is configured to establish a radio resource control (RRC) connection with a donor node; the second radio interface is configured to serve a cell to communicate with a wireless terminal. The wireless terminal may be a user equipment (UE) or a child IAB node. The IAB parent node comprises processor circuitry and transmitter circuitry. The processor circuitry is configured to: detect a radio link failure (RLF) on an upstream path to the donor node, provide updated system information based on the RLF, the updated system information comprising at least one cell status indicating that the cell is not allowed to camp on; and, generate a notification message comprising notification information configured to indicate whether the wireless terminal is to initiate an acquisition procedure to acquire the system information (a) immediately, or (b) after a next modification period boundary. The transmitter circuitry is configured to transmit, using the second interface, to the wireless terminal: the notification message and the updated system information. In another of its aspects the technology disclosed herein concerns a method of operating such a node.
In yet another of its aspects the technology disclosed herein concerns a wireless terminal that communicates with an integrated access and backhaul (IAB) parent node. The wireless terminal comprises receiver circuitry and processor circuitry. The receiver circuitry is configured to receive a notification message. The processor circuitry is configured when camping on a cell served by the IAB parent node, to obtain from the notification message information indicating whether to initiate an acquisition procedure (a) immediately or (b) after a next modification period boundary; to initiate, based on the notification message, an acquisition procedure to acquire system information, the system information comprising at least one cell status, the at least one cell status indicating whether or not the cell is allowed to camp on, and; to initiate, based on the at least one cell status, a cell selection procedure. In another of its aspects the technology disclosed herein concerns a method of operating such a wireless terminal.
In the following description, for purposes of explanation and not limitation, specific details are set forth such as particular architectures, interfaces, techniques, etc. in order to provide a thorough understanding of the technology disclosed herein. However, it will be apparent to those skilled in the art that the technology disclosed herein may be practiced in other embodiments that depart from these specific details. That is, those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the technology disclosed herein and are included within its spirit and scope. In some instances, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the technology disclosed herein with unnecessary detail. All statements herein reciting principles, aspects, and embodiments of the technology disclosed herein, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure.
Thus, for example, it will be appreciated by those skilled in the art that block diagrams herein can represent conceptual views of illustrative circuitry or other functional units embodying the principles of the technology. Similarly, it will be appreciated that any flow charts, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.
As used herein, the term “core network” can refer to a device, group of devices, or sub-system in a telecommunication network that provides services to users of the telecommunications network. Examples of services provided by a core network include aggregation, authentication, call switching, service invocation, gateways to other networks, etc.
As used herein, the term “wireless terminal” can refer to any electronic device used to communicate voice and/or data via a telecommunications system, such as (but not limited to) a cellular network. Other terminology used to refer to wireless terminals and non-limiting examples of such devices can include user equipment terminal, UE, mobile station, mobile device, access terminal, subscriber station, mobile terminal, remote station, user terminal, terminal, subscriber unit, cellular phones, smart phones, personal digital assistants (“PDAs”), laptop computers, tablets, netbooks, e-readers, wireless modems, etc.
As used herein, the term “access node”, “node”, or “base station” can refer to any device or group of devices that facilitates wireless communication or otherwise provides an interface between a wireless terminal and a telecommunications system. A non-limiting example of a base station can include, in the 3GPP specification, a Node B (“NB”), an enhanced Node B (“eNB”), a home eNB (“HeNB”), a gNB (for a New Radio [“NR”] technology system), or some other similar terminology.
As used herein, the term “telecommunication system” or “communications system” can refer to any network of devices used to transmit information. A non-limiting example of a telecommunication system is a cellular network or other wireless communication system.
As used herein, the term “cellular network” or “cellular radio access network” can refer to a network distributed over cells, each cell served by at least one fixed-location transceiver, such as a base station. A “cell” may be any communication channel that is specified by standardization or regulatory bodies to be used for International Mobile Telecommunications-Advanced (“IMTAdvanced”). All or a subset of the cell may be adopted by 3GPP as licensed bands (e.g., frequency band) to be used for communication between a base station, such as a Node B, and a UE terminal. A cellular network using licensed frequency bands can include configured cells. Configured cells can include cells of which a UE terminal is aware and in which it is allowed by a base station to transmit or receive information. Examples of cellular radio access networks include E-UTRAN, and any successors thereof (e.g., NUTRAN).
Any reference to a “resource” herein means “radio resource” unless otherwise clear from the context that another meaning is intended. In general, as used herein a radio resource (“resource”) is a time-frequency unit that can carry information across a radio interface, e.g., either signal information or data information.
An example of a radio resource occurs in the context of a “frame” of information that is typically formatted and prepared, e.g., by a node. In Long Term Evolution (LTE) a frame, which may have both downlink portion(s) and uplink portion(s), is communicated between the base station and the wireless terminal. Each LTE frame may comprise plural subframes. For example, in the time domain, a 10 ms frame consists of ten one millisecond subframes. An LTE subframe is divided into two slots (so that there are thus 20 slots in a frame). The transmitted signal in each slot is described by a resource grid comprised of resource elements (RE). Each column of the two dimensional grid represents a symbol (e.g., an OFDM symbol on downlink (DL) from node to wireless terminal; an SC-FDMA symbol in an uplink (UL) frame from wireless terminal to node). Each row of the grid represents a subcarrier. A resource element (RE) is the smallest time-frequency unit for downlink transmission in the subframe. That is, one symbol on one sub-carrier in the sub-frame comprises a resource element (RE) which is uniquely defined by an index pair (k,l) in a slot (where k and l are the indices in the frequency and time domain, respectively). In other words, one symbol on one sub-carrier is a resource element (RE). Each symbol comprises a number of sub-carriers in the frequency domain, depending on the channel bandwidth and configuration. The smallest time-frequency resource supported by the standard today is a set of plural subcarriers and plural symbols (e.g., plural resource elements (RE)) and is called a resource block (RB). A resource block may comprise, for example, 84 resource elements, i.e., 12 subcarriers and 7 symbols, in case of normal cyclic prefix
In 5G New Radio (“NR”), a frame consists of 10 ms duration. A frame consists of 10 subframes with each having 1 ms duration similar to LTE. Each subframe consists of slots. Each slot can have either 14 (normal CP) or 12 (extended CP) OFDM symbols. A Slot is typical unit for transmission used by scheduling mechanism. NR allows transmission to start at any OFDM symbol and to last only as many symbols as required for communication. This is known as “mini-slot” transmission. This facilitates very low latency for critical data communication as well as minimizes interference to other RF links. Mini-slot helps to achieve lower latency in 5G NR architecture. Unlike slot, mini-slots are not tied to the frame structure. It helps in puncturing the existing frame without waiting to be scheduled. See, for example, https://www.rfwireless-world.com/5G/5G-NR-Mini-Slot.html, which is incorporated herein by reference. A mobile network used in wireless networks may be where the source and destination are interconnected by way of a plurality of nodes. In such a network, the source and destination may not be able to communicate with each other directly due to the distance between the source and destination being greater than the transmission range of the nodes. That is, a need exists for intermediate node(s) to relay communications and provide transmission of information. Accordingly, intermediate node(s) may be used to relay information signals in a relay network, having a network topology where the source and destination are interconnected by means of such intermediate nodes. In a hierarchical telecommunications network, the backhaul portion of the network may comprise the intermediate links between the core network and the small subnetworks of the entire hierarchical network. Integrated Access and Backhaul (IAB) Next generation NodeB use 5G New Radio communications such as transmitting and receiving NR User Plane (U-Plane) data traffic and NR Control Plane (C-Plane) data. Both, the UE and gNB may include addressable memory in electronic communication with a processor. In one embodiment, instructions may be stored in the memory and are executable to process received packets and/or transmit packets according to different protocols, for example, Medium Access Control (MAC) Protocol and/or Radio Link Control (RLC) Protocol.
A mobile network used in wireless networks may be where the source and destination are interconnected by way of a plurality of nodes. In such a network, the source and destination may not be able to communicate with each other directly due to the distance between the source and destination being greater than the transmission range of the nodes. That is, a need exists for intermediate node(s) to relay communications and provide transmission of information. Accordingly, intermediate node(s) may be used to relay information signals in a relay network, having a network topology where the source and destination are interconnected by means of such intermediate nodes. In a hierarchical telecommunications network, the backhaul portion of the network may comprise the intermediate links between the core network and the small subnetworks of the entire hierarchical network. Integrated Access and Backhaul (IAB) Next generation NodeB use 5G New Radio communications such as transmitting and receiving NR User Plane (U-Plane) data traffic and NR Control Plane (C-Plane) data. Both, the UE and gNB may include addressable memory in electronic communication with a processor. In one embodiment, instructions may be stored in the memory and are executable to process received packets and/or transmit packets according to different protocols, for example, Medium Access Control (MAC) Protocol and/or Radio Link Control (RLC) Protocol.
In some aspects of the embodiments for handling of radio link failures in wireless relay networks, disclosed is a Mobile Termination (MT) functionality—typically provided by the User Equipment (UE) terminals—that may be implemented by Base Transceiver Stations (BTSs or BSs) nodes, for example, IAB nodes. In one embodiment, the MT functions may comprise common functions such as: radio transmission and reception, encoding and decoding, error detection and correction, signaling, and access to a SIM.
In a mobile network, an IAB child node may use the same initial access procedure (discovery) as an access UE to establish a connection with an IAB node/donor or parent-thereby attaching to the network or camping on a cell. In one embodiment, Radio Resource Control (RRC) protocol may be used for signaling between 5G radio network and UE, where RRC may have at least two states (e.g., RRC_IDLE and RRC_CONNECTED) and state transitions. The RRC sublayer may enable establishing of connections based on the broadcasted system information and may also include a security procedure. The U-Plane may comprise of PHY, MAC, RLC and PDCP layers.
Embodiments of the present system disclose methods and devices for an IAB-node to inform child nodes and/or UEs of upstream radio conditions and accordingly, the term IAB-node may be used to represent either a parent IAB-node or a child IAB-node, depending on where the IAB-node is in the network communication with the IAB-donor which is responsible for the physical connection with the core network. Embodiments are disclosed where an IAB-node (child IAB-node) may follow the same initial access procedure as a UE, including cell search, system information acquisition, and random access, in order to initially set up a connection to a parent IAB-node or an IAB-donor. That is, when an IAB base station (eNB/gNB) needs to establish a backhaul connection to, or camp on, a parent IAB-node or an IAB-donor, the IAB-node may perform the same procedures and steps as a UE, where the IAB-node may be treated as a UE but distinguished from a UE by the parent IAB-node or the IAB-donor.
In the disclosed embodiments for handling radio link failures in wireless relay networks, MT functionality—typically offered by a UE—may be implemented on an IAB-node. In some examples of the disclosed systems, methods, and device embodiments, consideration may be made in order for a child IAB-node to monitor a radio condition on a radio link to a parent IAB-node—where the parent IAB-node may itself be a child IAB-node in communication with an IAB-donor.
With reference to
With further reference to
Embodiments include a mobile network infrastructure where a number of UEs are connected to a set of IAB-nodes and the IAB-nodes are in communication with each other for relay and/or an IAB-donor using the different aspects of the present embodiments. In some embodiments, the UE may communicate with the CU of the IAB-donor on the C-Plane using RRC protocol and in other embodiments, using Service Data Adaptation Protocol (SDAP) and/or Packet Data Convergence Protocol (PDCP) radio protocol architecture for data transport (U-Plane) through NR gNB. In some embodiments, the DU of the IAB-node may communicate with the CU of the IAB-donor using 5G radio network layer signaling protocol: F1 Application Protocol (F1-APS′) which is a wireless backhaul protocol that provides signaling services between the DU of an IAB-node and the CU of an IAB-donor. That is, as further described below, the protocol stack configuration may be interchangeable, and different mechanism may be used.
As illustrated by the diagram shown in
As described above, following the RRC connection establishment procedure, the DU of IAB-node 1 and IAB-donor may proceed with F1 setup procedure using the F1-APS' protocol, which may activate one or more cells served by the DU of IAB-node 1-thereby allowing other IAB nodes and/or UEs to camp on the cell. In this procedure, the Adaptation Layer for IAB-node 1 and IAB-donor may be configured and activated as well.
As further shown in
As shown in
In an example, non-limiting embodiment and mode shown in
The wireless relay network 20 of
In some configurations, the DU of each IAB-node/donor, e.g., the distributed unit 34 of parent node 22 and the relay node distributed unit 62 of IAB-relay node 24, may broadcast information necessary to be discovered by UEs and/or other child IAB-nodes. Such information may comprise synchronization signals, master information block (MIB) and one or more system information blocks (SIBs). The SIBs may further comprise an essential SIB (e.g. SIB1) and other SIBs (e.g. SIB2, SIB3, . . . etc.). As used herein, an “essential SIB” is a type of SIB that may carry information necessary for camping and initial access, whereas the other SIBs may carry all other information, such as information about neighbor cells.
When the wireless relay network 20 detects a congestion (or any other reasons), the network 20 may desire to restrict usage of the network resource usage from some UEs and/or IAB-nodes. In some configurations, such restrictions may be achieved by a cell barring, or “cell reservations”.
In a cellular network, the cell barring may be implemented by including barring status in a broadcast signal from base stations. Any wireless terminal in the coverage of a cell served by such a base station may first acquire the broadcast signal and examine the barring status. If the barring status indicates that the cell is restricted, e.g., barred, the wireless terminal may consider that this cell is not suitable for camping and look for other cells. Otherwise, the terminal may camp on the cell.
For example, in the 5G cellular system, a gNB may broadcast information for cell barring/reservations (3GPP TS 38.331). The information for cell barring/reservations which is broadcast may include, for example, an information element cell cellBarred which is included in a Master System Information Block in the example manner shown in Table 1; an information element cellAccessrelatedInfo which is included in a SIB1 message in the example manner shown in Table 2 and having example content shown in Table 3; and an information element PLMN-IdentityInfoList which is included in the information element cellAccessrelatedInfo and which has content as shown in Table 4.
In some example embodiments and modes, when camping on a cell, a terminal such as user equipment 30 or an IAB-node such as IAB-relay node 24 may acquire MIB and SIB1 formatted as shown above in Table 1 and Table 2, respectively, and may proceed to processing the information related to cell barring/reservations. In some configurations, the UE 30 or the IAB-node 24 may follow the procedure or listing specified in 3GPP TS 38.304, which is also shown in Table 5. The procedure described and shown in Table 5 may also be referred to as “listing 1”, and specifically includes a procedure for a “barred cell” which involves an end portion of the listing which begins with an includes the last non-indented line thereof.
In some configurations, the Access Identities may be defined in 3GPP TS 22.261 as shown in Table 6.
Thus, in the example embodiment of
There may be some exceptions to the general rule of both IAB-relay node 24 and user equipment 30 performing the standard barring procedure 110. A first exception in a case in which the information element cellReservedForOperatorUse (see Table 5) is “reserved” for some of the PLMNs, and the UE and the IAB-node camp on different PLMNs. In this case, a node (UE or IAB-node) that selects one of the “reserved” PLMNs may be barred, while the other that selects a PLMN not “reserved” may camp on the cell.
A second exception is a case in which the IAB-node is configured with Access Identity 11 or 15 (see Table 6). In this case, when selecting one of the “reserved” PLMNs, the UE (configured with Access Identity other than 11 or 15) may be barred while the IAB-node may not be barred.
In a second example generic embodiment and mode and its sub-embodiments described herein, an example wireless relay network 20 includes parent node 22, IAB-relay node 24, and user equipment 30 as shown in
During a cell selection/reselection process, a UE 30 or the MT relay node mobile termination unit 60 of an IAB-node 24 may determine whether a cell allows camping, e.g., the cell is considered as a candidate for cell selection/reselection, based on the current barring mode of the cell.
In one configuration, the barring mode, e.g., the cell barring information, in part or in whole, may be broadcasted by the parent node using one or more fields, parameters or information elements in the system information.
Accordingly, the information element cellBarredIAB may be configured independently from the fields disclosed in Embodiment 1, e.g., independently of cellBarred, cellAccessrelatedInfo; and PLMN-IdentityInfoList. A wireless terminal, with a terminal type being either a UE or a relay node, e.g., a user equipment 30 or a relay node mobile termination unit 60 of an IAB-node 24, may determine which barring fields/parameters to use, depending on its terminal type. For example, in a case that the terminal type is a relay node, the relay node mobile termination unit 60 of the IAB-node 24 may ignore cellBarred in MIB, which is applicable only to UEs (not to IAB-nodes) and may use cellBarredIAB instead to determine the cell status (barred or not barred). Meanwhile, in a case that the terminal type is a UE such as user equipment 30, the UE may behave as disclosed in Embodiment 1: use cellBarred to determine the cell status. In either case, if the cell status “barred” is indicated, the procedure (procedure for a “barred” cell) in Listing 1 of Table 5 may be performed.
In some example configurations, the user equipment 30 may ignore or may not recognize cellBarredIAB, if in fact the user equipment 30 receives the cellBarredIAB information element. In another configuration, the UE may not even attempt to receive the system information block where cellBarredIAB is included.
Thus, in an example configuration, the first cell status information 54 may be obtained from the information element cellBarred and the second cell status information 56 may be obtained from the information element cellBarredIAB. In such a configuration, the barring modes (1) to (4) disclosed in Table 7 above may be achieved in the manner shown in Table 9.
It should be noted that, in a case that a node does not support IAB relaying functionality, e.g., in a case in which the node is not configured to be a parent node of other IAB nodes, the node may set “barred” to cellBarredIAB, in order to prevent other IAB-nodes from camping on the cell served by such node.
Furthermore, in one example configuration cellBarredIAB may be optionally present in the system information block(s). If not present, the relay node mobile termination unit 60 of the IAB-node that receives the system information block(s) may treat the cell as the cell status is “barred”.
Embodiment 2-2 is a sub-embodiment of Embodiment 2, and in a sense is logically equivalent to sub-embodiment 2-1. Elements and functionalities of the nodes and terminals of sub-embodiment 2-2 are essentially the same as those of
Accordingly, the information element or field cellIABSupport may be configured independently from the fields disclosed in the previous embodiments. A wireless terminal, with a terminal type being either a UE 30 or a relay node (a relay node mobile termination unit 60 of an IAB-node 24), may determine which barring fields/parameters to use, depending on its terminal type. For example, in a case that the terminal type is a relay node 24, the relay node mobile termination unit 60 of the IAB-node 24 may ignore cellBarred in MIB and use cellIABSupport to determine if the IAB-node 24 is allowed to camp on the cell. If cellIABSupport is “supported” (e.g., the iab-Support field is present), the IAB-node 24 may consider the cell as a candidate. If cellIABSupport is “notSupported” (e.g., the iab-Support field is absent), the IAB-node may treat the cell as if the cell status is “barred”. On the other hand, in a case that the terminal type is a UE 30, the UE 30 may behave as disclosed in Embodiment 1: use cellBarred to determine the cell status. In either case, if the cell status “barred” is indicated or to be treated as if the cell status is “barred”, the procedure or Listing 1 (procedure for a “barred” cell) of Table 5 may be performed.
The acts of
In some configurations of the sub-embodiment 2-2, the UE 30 may ignore or may not recognize the information element cellIABSupport, if the user equipment 30 in fact receives information element cellIABSupport. In another configuration of the sub-embodiment 2-2, the UE may not attempt to receive the system information block where cellIABSupport is included.
Thus, in an example configuration for the sub-embodiment 2-2, the barring modes (1) to (4) disclosed in Table 7 may be achieved using the information element cellIABSupport in the manner of Table 11.
Furthermore, in one example configuration the information element cellIABSupport may be optionally present in the system information block(s). If not present, the relay node mobile termination unit 60 of the IAB-node 24 that receives the system information block(s) may consider cellIABSupport=notSupported. Alternatively, in another configuration, the relay node mobile termination unit 60 of the IAB node 24 may treat the absence of cellIABSupport in the system information block(s) as “Supported”.
Embodiment 2-3 is a sub-embodiment of Embodiment 2, and in a sense is logically equivalent to sub-embodiment 2-1 and sub-embodiment 2-2. Elements and functionalities of the nodes and terminals of sub-embodiment 2-2 are essentially the same as those of
The field cellReservedForIABUse may indicate that the cell is reserved for IAB-nodes, e.g., that only IAB-nodes are allowed to camp. In one example configuration, this field cellReservedForIABUse is identical to cellReservedForOtherUse disclosed on Embodiment 1. In another example configuration, this field cellReservedForIABUse is a separate field. The field cellIABSupport is the field disclosed in Embodiment 2-2. Similar to the previous embodiments, each of these fields of sub-embodiment 2-3 may be included in one or more of the system information blocks (MIB, SIB1, or other SIB(s)), as depicted by way of example in
In sub-embodiment 2-3, the information element cellBarred in MIB may apply to both UEs 30 and IAB-nodes 24. That is, if cellBarred=barred, camping is barred for UEs 30 as well as IAB-nodes 24. Otherwise, the UEs/IAB-nodes may proceed to examining cellReservedForIABUse. If cellReservedForIABUse is true, the cell is reserved for IAB-nodes and therefore the UE 30 may treat this cell as if it is barred, while the relay node mobile termination unit 60 of the IAB-node 24 may consider this cell as a candidate. The information element cellReservedForIABUse being “true” may also means that the cell supports the IAB relaying functionality and thus the field cellIABSupport may not be present (absent or omitted). If cellReservedForIABUse is “false” or not present, then the UE 30 may consider the cell as a candidate while the MT of the IAB-node may further examine cellIABSupport and consider the cell as a candidate only when cellIABSupport=“supported”, otherwise it may treat the cell as if it is barred.
Subject to the more detailed description provided above, the acts of
Thus, in an example configuration for the sub-embodiment 2-3, the barring modes (1) to (4) of Table 7 may be achieved in the example manner of Table 13.
For example, in embodiment 3 and the system of
For example, Listing 1 of Table 5 specifies that the UE 30 shall exclude the barred cell as a candidate for cell selection/reselection for 300 seconds. While this may still apply to UEs 30 in executing the UE barring procedure 132, the relay node mobile termination unit 60 of the IAB-node 24 may use a different time duration (other than 300 seconds) for the exclusion of the barred cell as a candidate when executing the relay barring procedure 130. The different time duration may be shorter or longer than 300 seconds, or may be infinity (permanently barred). The different time duration may be pre-configured, configured by network via dedicated signaling or configured by broadcast via system information (MIB, SIB1 or other SIB(s)). Other examples may include treating the cell as if intraFreqReselection=allowed (or not allowed) regardless of its value in MIB.
Features of this Embodiment 3 may be combined with features of other example embodiments and modes described herein. For example, the operation and mode of embodiment 3 may be applied to Embodiment 2-1, Embodiment 2-2, and/or Embodiment 2-3.
In embodiment and
If the field cellServiceAvailable indicates that the IAB service is available, the UE 30 or the relay node mobile termination unit 60 of an IAB-node 24 may follow one or some of the previously disclosed embodiments. If the field cellServiceAvailable indicates the IAB service is not available, in one configuration the UE 30 or the relay node mobile termination unit 60 of an IAB-node 24 may treat this cell as if it is barred. In this case, similar to the operation and mode disclosed in Embodiment 2-3, the UE 30 or the relay node mobile termination unit 60 of the IAB-node 24 may apply a different time duration for barring (typically a shorter duration). In another configuration, if the IAB service is not available, the UE 30 or the relay node mobile termination unit 60 of the IAB-node IAB-relay node 24 may consider this cell as a candidate with a lower priority and may camp on this cell only when it is not able to find other higher priority cells.
Thus, in Embodiment 4, the cell barring information may comprise first status, second status and third status. The first status may represent cell barring status commonly applied to the wireless terminal of any terminal type, such as the information element cellBarred. The second status may indicate whether or not the cell is reserved for the wireless terminal of the terminal type being a relay node, such as (for one example) cellBarredIAB or cellIABSupport. The third status may indicate whether the cell supports relaying functionality required by the wireless terminal of the terminal type being a relay node, e.g., cellServiceAvailable which herein is also known as relay support field 140.
In some wireless relay networks a node serving a cell may notify terminals camping on the cell upon a change in the content of the system information in the cell (available on BCCH). This act is also referred as system information change notification. For example, as specified in 3GPP TS 36.331, in the LTE radio access network utilizes Paging Message for the notification. As another example, as specified in 3GPP TS 38.331, the 5G radio access network broadcasts Short Message on Physical Downlink Control Channel (PDCCH). The Short Message of 3GPP TS 38.331 is formatted as shown in Table 15
As explained above, in some configurations of the IAB-based relay network, the system information may comprise fields, parameters, information elements and/or SIBs dedicated for IAB-nodes. “Dedicated” to IAB-nodes means not used by UEs 30, e.g., by UE-type wireless terminal s). The fields, cellBarredIAB, cellIABSupport, cellIReservedForIABUse or cellServiceAvailable, disclosed in the aforementioned embodiments respectively indicate information regarding cell barring, cell reservation, IAB support, and IAB service availability, and are examples of such fields that are dedicated for IAB nodes and which may be included in transmitted system information. If the node serving the cell were to broadcast the system information change notification due to a change made on such a field to all wireless terminals in the cell, it would result in unnecessary system information acquisition by UE-type terminals 30 since the operation of UE-type terminals 30 is essentially impervious to such fields.
Accordingly, embodiment 5 includes several sub-embodiments of wireless relay networks 20 in which transmission of system information change notifications are governed in accordance with pertinence to IAB-node information, e.g., whether and to what extent the system information change involves a system information dedicated to IAB-type nodes. It should be understood that the operation and mode disclosed in the sub-embodiments of embodiment 5 may be applicable not only to the case where Short Message is used for broadcasting system information change notifications, but also to the case where Paging Message, or any other message is used.
In Embodiment 5-1, a change made on the fields, parameters, information elements and/or SIBs dedicated for IAB-nodes may not result in system information change notification. For instance, upon changing the value of cellBarredIABI, cellIABSupport, cellIReservedForIABUse or cellServiceAvailable, the node serving the cell may suppress, e.g., not transmit, broadcast of the Short Message. In this regard, for the example wireless relay network 20 of
Although not shown as such, the system information controller 120 may also include the first cell status information 54 and second cell status information 56 as shown, for example, in
Thus, the transmitter circuitry 42 of parent node 22 of Embodiment 5-1 and
In example Embodiment 5-2 and
Thus, the example embodiment 5-2 and
For the example embodiment 5-2, both user equipment 30 and IAB-relay node 24 receive the short message of Table 16, e.g., in a physical downlink control channel (PDCCH) message. The user equipment 30, which is not concerned with changes in system information that affect only IAB wireless terminals, e.g., not concerned with IAB-dedicated system information, need only look at bit 1 and bit 2 in order to ascertain whether the system information change notification affects the user equipment 30. Thus, for the example embodiment 5-2 the system information may comprise one or more first system information blocks (SIBs) and the notification message may comprise one or more first bits, such as bit 1 and bit 2 of Table 16. Each of such first bits may be associated with a first SIB or a group of first SIBs, and each of the first bits may indicate whether or not a change is made on the associated first SIB(s).
An IAB-relay node 24, on the other hand, should look at least at bit 3 of the short message of Table 16 in order to determine if the system information change notification is relevant for IAB-relay node type wireless terminals. In other words, when the information dedicated to the wireless terminal of the terminal type being a relay node comprises one or more information elements included in one or more first SIBs, the notification message may further comprises at least one second bit, such as bit 3 of Table 16, which indicates that a change is made on the one or more information elements included in one or more first SIBs.
In one example implementation or configuration of embodiment 5-2 and
In another implementation or configuration of embodiment 5-2 and
Thus, it should be understood that the system information comprises one or more second SIBs dedicated to the wireless terminal of the terminal type being a relay node including at least a part of the information dedicated to the wireless terminal of the terminal type being a relay node, and the notification message may comprise one or more third bits, each of the third bits being associated with the one or more second SIBs dedicated to the wireless terminal of the terminal type being a relay node, each of the third bits indicating whether or not a change is made on the associated second SIBs.
Again, although not shown as such, the system information controller 120 may also include the first cell status information 54 and second cell status information 56 as shown, for example, in
In example Embodiment 5-3 and
In one example configuration or implementation, the second notification message generated by second short message system information change notification generator 128 may be received by the relay node mobile termination unit 60 of the IAB-node 24 and may be ignored by the UE 30.
In some example configurations or implementations, the first notification massage generated by first short message system information change notification generator 126 may be used to notify a change made on information (fields, parameters, information elements and/or SIBs) in the system information common for UEs and IAB-nodes, whereas the second notification message generated by second short message system information change notification generator 128 may be used to notify a change made on information in the system information dedicated to IAB-nodes. Upon receiving the first notification message, the UE or the relay node mobile termination unit 60 of the IAB-node 24 may attempt to reacquire the affected (changed) SIBs indicated by the first notification message. Meanwhile, only the relay node mobile termination unit 60 of the IAB-node 24 may receive the second notification message and may attempt to reacquire the affected (changed) SIBs indicated by the second notification message.
It should thus be understood that the parent node 22 of
Both the user equipment 30 and IAB-relay node 24 of the example embodiment 5-3 and of
Again, although not shown as such, the system information controller 120 may also include the first cell status information 54 and second cell status information 56 as shown, for example, in
In a case that a parent IAB-node detects a radio link failure (RLF) on its upstream link (towards an IAB-donor) and fails to recover the RLF, such RLF-detecting parent IAB-node may send a backhaul (BH) RLF indication to downstream child IAB-nodes/UEs. The BH RLF indication may be transmitted on Backhaul Adaptation Protocol (BAP), per 3GPP TS 38.340, physical layer signaling, Medium Access Control (MAC), or any other protocol layer. In this situation, additionally or alternatively, the parent node may set cell barring status to “barred” for the cell(s) served by the parent node, in order to prevent child IAB-nodes/UEs from camping on the affected cell(s).
A change of barring status may be reflected in a change in system information, which may need to be informed to child IAB-nodes/UEs. Table 17-1 is a listing or description of an example operation for system information updates, per 3GPP TS 38.300 and TS 38.331.
When IAB parent node 23 changes such cell barring status, as shown by arrow 25-3 the IAB parent node 23 may transmit a notification message, e.g., a Short Message, wherein an information element such as systemInformationModification is set in the modification period preceding the modification period where the cell barring status gets updated. According to the operation described above, the child IAB-node/UE in RRC_IDLE/RRC_INACTIVE may receive the Short Message during its DRX cycle, may wait for the next modification period boundary, and then may proceed to acquiring MIB, SIB1 and/or other SIB(s).
In the operation discussed above relative to
According to the sixth embodiment, a notification message may comprise an information element indicating whether a change occurring on one or more MIB/SIB(s), but not on ETWS/CMAS SIBs, is effective immediately or not.
It should be understood that the node processor(s) 64-23; the node processor(s) 64-24; and terminal processor(s) 90 typically perform and execute many other operations and procedures in addition to those described herein. For simplicity only operations and procedures germane to aspects of this sixth embodiment are described.
From the foregoing and remaining discussion, it is understood that the IAB parent node 23 an integrated access and backhaul (IAB) parent node comprising a first radio interface 144 and a second radio interface 146. The first radio interface is configured to establish a radio resource control (RRC) connection with a donor node, such as donor IAB node 22. The second radio interface is configured to serve a cell to communicate with a wireless terminal. The wireless terminal may a user equipment (UE) 30 or a child IAB node 24. The IAB parent node 23 comprises processor circuitry, such as node processor(s) 64-23 and transmitter circuitry, such as node transmitter circuitry 67 included in distributed unit 66-23. The node processor(s) 64-23, e.g., radio link failure (RLF) detector 152, are configured to detect a radio link failure (RLF) on an upstream path to the donor node. The node processor(s) 64-23, e.g., system information generator/updater 154, are further configured to provide updated system information based on the RLF. The updated system information comprises at least one cell status indicating that the cell is not allowed to camp on (e.g., the cell is not considered as a candidate). The node processor(s) 64-23, e.g., notification generator 156, are further configured to generate a notification message. The notification message comprises notification information configured to indicate whether the wireless terminal is to initiate an acquisition procedure to acquire the system information (a) immediately (e.g., in a current modification period), or (b) after a next modification period boundary. The transmitter circuitry, e.g., node transmitter circuitry 67, is configured to transmit using the second interface, to the wireless terminal, both the notification message and the updated system information.
From the foregoing and remaining discussion, it is understood that the child node or wireless terminal may be an IAB node in the form of IAB node 24 or a UE 30. In either form the wireless terminal or child IAB node communicates with an integrated access and backhaul (IAB) parent node, e.g., IAB parent node 23, over the second radio interface 146. The wireless terminal comprises receiver circuitry and processor circuitry. When the child node is an IAB node 24, for example, the receiver circuitry may take the form of mobile termination 60-24 and the processor circuitry may take the form of node processor(s) 64-24 as shown in
Thus, in the sixth example embodiment and mode, as illustrated for example by
Meanwhile, upon receiving the notification message 158 or Short Message with both systemInfoModification and systemInfoModificationImmediate set to 1, Child Node in
Based on the implementation above, in conjunction with this sixth example embodiment and mode the aforementioned example operation for system information updates in the listing of Table 17-1 may be modified as shown in the listing of Table 17-2.
It should be understood that IAB parent node 23 of
In the implementation of the notification message 158 or Short Message described above, the two bits in the Short Message, i.e. the systemInfoModification bit and the systemInfoModificationImmediate bit are used to specify an action of the recipient (e.g. Child Node in
Alternatively, Table 19-2 is different logic which may be implemented instead of Table 19-1, wherein systemInfoModificationImmediate bit itself may indicate an immediate change of non-EWTS/CMAS system information.
It should be noted that in a case that the notification message 158 or Short Message indicates to acquire non-EWTS/CMAS system information, the child UE/IAB-node may not need to acquire all of the non-EWTS/CMAS SIBs. Indeed, when the child UE/IAB-node acquires MIB and SIB1, it knows, from scheduling information. e.g. siSchedulingInfo in SIB1, which SIB(s) is updated. Therefore, the child UE/IAB-node may attempt to acquire the updated SIB(s).
The operation and mode disclosed in this embodiment, especially the method for instructing UEs/IAB-nodes to acquire updated system information before the next modification period boundary using a notification message, may be used not only in a case of a backhaul RLF, but also in other situations where an immediate attention for updates on MIB and/or non-ETWS/CMAS SIBs is needed.
As is understood by those skilled in the art, in some telecommunications system messages, signals, and/or data are communicated over a radio or air interface using one or more “resources”, e.g., “radio resource(s)”. Each node or terminal described herein may comprise an unillustrated frame/message generator/handler which serves to handle messages, signals, and data received from other nodes, including but not limited to the BH RLF indication and the notification message 158 described herein.
Certain units and functionalities of the systems 20 may be implemented by electronic machinery. For example, electronic machinery may refer to the processor circuitry described herein, such as node processor(s) 64-12 and 64-24 and terminal processor(s) 90. Moreover, the term “processor circuitry” is not limited to mean one processor, but may include plural processors, with the plural processors operating at one or more sites. Moreover, as used herein the term “server” is not confined to one server unit, but may encompasses plural servers and/or other electronic equipment, and may be colocated at one site or distributed to different sites. With these understandings,
An memory or register described herein may be depicted by memory 294, or any computer-readable medium, may be one or more of readily available memory such as random access memory (RAM), read only memory (ROM), floppy disk, hard disk, flash memory or any other form of digital storage, local or remote, and is preferably of non-volatile nature, as and such may comprise memory. The support circuits 299 are coupled to the processors 290 for supporting the processor in a conventional manner. These circuits include cache, power supplies, clock circuits, input/output circuitry and subsystems, and the like.
Although the processes and methods of the disclosed embodiments may be discussed as being implemented as a software routine, some of the method steps that are disclosed therein may be performed in hardware as well as by a processor running software. As such, the embodiments may be implemented in software as executed upon a computer system, in hardware as an application specific integrated circuit or other type of hardware implementation, or a combination of software and hardware. The software routines of the disclosed embodiments are capable of being executed on any computer operating system, and is capable of being performed using any CPU architecture.
The functions of the various elements including functional blocks, including but not limited to those labeled or described as “computer”, “processor” or “controller”, may be provided through the use of hardware such as circuit hardware and/or hardware capable of executing software in the form of coded instructions stored on computer readable medium. Thus, such functions and illustrated functional blocks are to be understood as being either hardware-implemented and/or computer-implemented, and thus machine-implemented.
In terms of hardware implementation, the functional blocks may include or encompass, without limitation, digital signal processor (DSP) hardware, reduced instruction set processor, hardware (e.g., digital or analog) circuitry including but not limited to application specific integrated circuit(s) [ASIC], and/or field programmable gate array(s) (FPGA(s)), and (where appropriate) state machines capable of performing such functions.
In terms of computer implementation, a computer is generally understood to comprise one or more processors or one or more controllers, and the terms computer and processor and controller may be employed interchangeably herein. When provided by a computer or processor or controller, the functions may be provided by a single dedicated computer or processor or controller, by a single shared computer or processor or controller, or by a plurality of individual computers or processors or controllers, some of which may be shared or distributed. Moreover, use of the term “processor” or “controller” may also be construed to refer to other hardware capable of performing such functions and/or executing software, such as the example hardware recited above.
Nodes that communicate using the air interface also have suitable radio communications circuitry. Moreover, the technology disclosed herein may additionally be considered to be embodied entirely within any form of computer-readable memory, such as solid-state memory, magnetic disk, or optical disk containing an appropriate set of computer instructions that would cause a processor to carry out the techniques described herein.
Moreover, each functional block or various features of the wireless terminal 30, parent node 22, and IAB-relay node 24 used in each of the aforementioned embodiments may be implemented or executed by circuitry, which is typically an integrated circuit or a plurality of integrated circuits. The circuitry designed to execute the functions described in the present specification may comprise a general-purpose processor, a digital signal processor (DSP), an application specific or general application integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic, or a discrete hardware component, or a combination thereof. The general-purpose processor may be a micro-processor, or alternatively, the processor may be a conventional processor, a controller, a microcontroller or a state machine. The general-purpose processor or each circuit described above may be configured by a digital circuit or may be configured by an analogue circuit. Further, when a technology of making into an integrated circuit superseding integrated circuits at the present time appears due to advancement of a semiconductor technology, the integrated circuit by this technology is also able to be used.
It will be appreciated that the technology disclosed herein is directed to solving radio communications-centric issues and is necessarily rooted in computer technology and overcomes problems specifically arising in radio communications. Moreover, the technology disclosed herein improves basic function of a radio access network, e.g., methods and procedures to deal with problematic issues such as governing or controlling which cells may be selected or re-selected by various types of nodes and terminals, in order to operate a wireless relay network 20 effectively and to reduce congestion in such operation.
The technology disclosed herein encompasses one or more of the following non-limiting, non-exclusive example embodiments and modes:
Example embodiment 1: An integrated access and backhaul (IAB) parent node comprising a first radio interface and a second radio interface, the first radio interface being configured to establish a radio resource control (RRC) connection with a donor node, the second radio interface being configured to serve a cell to communicate with a wireless terminal, the wireless terminal being a user equipment (UE) or a child IAB node, the IAB parent node comprising: processor circuitry configured to: detect a radio link failure (RLF) on an upstream path to the donor node; provide updated system information based on the RLF, the updated system information comprising at least one cell status indicating that the cell is not allowed to camp on; and, generate a notification message comprising notification information configured to indicate whether the wireless terminal is to initiate an acquisition procedure to acquire the system information (a) immediately, or (b) after a next modification period boundary; transmitter circuitry configured to transmit, using the second interface, to the wireless terminal: the notification message; and, the updated system information.
Example embodiment 2: The IAB parent node of Example embodiment 1, wherein in a case that the notification information indicates to initiate the acquisition procedure immediately, the notification information instructs the wireless terminal to initiate the acquisition procedure in a current modification period.
Example embodiment 3: The IAB parent node of Example embodiment 1, wherein the system information comprises a Master Information Block (MIB), a system information block type 1 (SIB1), and other SIBs excluding an Earthquake and Tsunami Warning System (ETWS) SIB(s) and Commercial Mobile Alert Service (CMAS) SIBs.
Example embodiment 4: The IAB parent node of Example embodiment 1, wherein the notification information is separate from an indication, included in the notification message, the indication indicating a change on the ETWS SIB(s) or the CMAS SIBs.
Example embodiment 5: The IAB parent node of Example embodiment 1, wherein the at least one cell status is a cell barring status indicating whether or not the cell is barred for the UE.
Example embodiment 6: The IAB parent node of Example embodiment 5, wherein the cell barring status is included in a Master Information Block (MIB).
Example embodiment 7: The IAB parent node of Example embodiment 1, wherein the at least one cell status is an IAB support status, the IAB support status indicating whether: the cell supports IAB and the cell is also considered as a candidate for the child IAB node, or the cell does not support IAB and/or the cell is barred for the child IAB node.
Example embodiment 8: The IAB parent node of Example embodiment 7, wherein the IAB support status is included in a system information block type 1 (SIB1).
Example embodiment 9: The IAB parent node of Example embodiment 1, wherein the notification information comprises a first information element indicating whether or not there is a change on the system information, and a second information element indicating whether to acquire the system information immediately or after the next modification boundary.
Example embodiment 10: The IAB parent node of Example embodiment 1, wherein the notification information comprises a first information element indicating whether or not to acquire the system information after a next modification period boundary, and a second information element indicating whether or not to acquire the system information immediately.
Example embodiment 11: The IAB parent node of Example embodiment 1, wherein the RLF is detected on the first radio interface.
Example embodiment 12: The IAB parent node of Example embodiment 1, wherein the RLF is detected based on a reception of a backhaul RLF indication message.
Example embodiment 13: A wireless terminal that communicates with an integrated access and backhaul (IAB) parent node, the wireless terminal comprising: receiver circuitry configured to receive a notification message, and; processor circuitry configured: when camping on a cell served by the IAB parent node, to obtain from the notification message information indicating whether to initiate an acquisition procedure (a) immediately or (b) after a next modification period boundary; to initiate, based on the notification message, an acquisition procedure to acquire system information, the system information comprising at least one cell status, the at least one cell status indicating whether or not the cell is allowed to camp on, and; to initiate, based on the at least one cell status, a cell selection procedure.
Example embodiment 14: The wireless terminal of Example embodiment 13, wherein in a case that the information indicates to initiate the acquisition procedure immediately, the acquisition procedure is initiated in a current modification period.
Example embodiment 15: The wireless terminal of Example embodiment 13, wherein the system information comprises a Master Information Block (MIB), a system information block type 1 (SIB1), and other SIBs excluding an Earthquake and Tsunami Warning System (ETWS) SIB(s) and Commercial Mobile Alert Service (CMAS) SIBs.
Example embodiment 16: The wireless terminal of Example embodiment 13, wherein the notification information is separate from an indication, included in the notification message, the indication indicating a change on the ETWS SIB(s) or the CMAS SIBs.
Example embodiment 17: The wireless terminal of Example embodiment 13, wherein the at least one cell status is a cell barring status indicating whether or not the cell is barred for the UE.
Example embodiment 18: The wireless terminal of Example embodiment 17, wherein the cell barring status is included in a Master Information Block (MIB).
Example embodiment 19: The wireless terminal of Example embodiment 13, wherein the at least one cell status is an IAB support status, the IAB support status indicating whether: the cell supports IAB and the cell is also considered as a candidate for the child IAB node, or the cell does not support IAB and/or the cell is barred for the child IAB node.
Example embodiment 20: The wireless terminal of Example embodiment 19, wherein the IAB support status is included in a system information block type 1 (SIB 1).
Example embodiment 21: The wireless terminal of Example embodiment 13, wherein the notification information comprises a first information element indicating whether or not there is a change on the system information, and a second information element indicating whether or not to acquire the system information immediately.
Example embodiment 22: The wireless terminal of Example embodiment 13, wherein the notification information comprises a first information element indicating whether or not to acquire the system information after a next modification period boundary, and a second information element indicating whether or not to acquire the system information immediately.
Example embodiment 23: A method for an integrated access and backhaul (IAB) parent node comprising a first radio interface and a second radio interface, the first radio interface being configured to establish a radio resource control (RRC) connection with a donor node, the second radio interface being configured to serve a cell to communicate with a wireless terminal, the wireless terminal being a user equipment (UE) or a child IAB node, the method comprising: detecting a radio link failure (RLF) on an upstream path to the donor node; providing updated system information based on the RLF, the updated system information comprises at least one cell status indicating that the cell is not allowed to camp on; transmitting, using the second interface, to the wireless terminal: a notification message comprising notification information indicating whether the wireless terminal initiates an acquisition procedure to acquire the system information (a) immediately, or (b) after a next modification period boundary, and; the updated system information.
Example embodiment 24: The method of Example embodiment 23, wherein in a case that the notification information indicates to initiate the acquisition procedure immediately, the information instructs the wireless terminal to initiate the acquisition procedure in a current modification period.
Example embodiment 25: The method of Example embodiment 23, wherein the system information comprises a Master Information Block (MIB), a system information block type 1 (SIB1), and other SIBs excluding an Earthquake and Tsunami Warning System (ETWS) SIB(s) and Commercial Mobile Alert Service (CMAS) SIBs.
Example embodiment 26: The method of Example embodiment 23, wherein the notification information is separate from an indication, included in the short message, the indication indicating a change on the ETWS SIB(s) or the CMAS SIBs.
Example embodiment 27: The method of Example embodiment 23, wherein the at least one cell status is a cell barring status indicating whether or not the cell is barred for the UE.
Example embodiment 28: The method of Example embodiment 27, wherein the cell barring status is included in a Master Information Block (MIB).
Example embodiment 29: The method of Example embodiment 23, wherein the at least one cell status is an IAB support status, the IAB support status indicating whether: the cell supports IAB and the cell is also considered as a candidate for the child IAB node, or the cell does not support IAB and/or the cell is barred for the child IAB node.
Example embodiment 30: The method of Example embodiment 29, wherein the IAB support status is included in a system information block type 1 (SIB1).
Example embodiment 31: The method of Example embodiment 23, wherein the notification information comprises a first information element indicating whether or not there is a change on the system information, and a second information element indicating whether to acquire the system information immediately or after the next modification boundary.
Example embodiment 32: The method of Example embodiment 23, wherein the notification information comprises a first information element indicating whether or not to acquire the system information after a next modification period boundary, and a second information element indicating whether or not to acquire the system information immediately.
Example embodiment 33: Example embodiment 23: The method of Example embodiment 23, wherein the RLF is detected on the first radio interface.
Example embodiment 34: The method of Example embodiment 23, wherein the RLF is detected based on a reception of a backhaul RLF indication message.
Example embodiment 35: A method for a wireless terminal that communicate with an integrated access and backhaul (IAB) parent node, the method comprising: camping on a cell served by the IAB parent node; receiving a notification message comprises notification information indicating whether to initiate the acquisition procedure immediately or after a next modification period boundary; initiating, based on the notification message, an acquisition procedure to acquire system information, the system information comprising at least one cell status, the at least one cell status indicating whether or not the cell is allowed to camp on, and; initiating, based on the at least one cell status, a cell selection procedure.
Example embodiment 36: The method of Example embodiment 35, wherein in a case that the notification information indicates to initiate the acquisition procedure immediately, the acquisition procedure is initiated in a current modification period.
Example embodiment 37: The method of Example embodiment 35, wherein the system information comprises a Master Information Block (MIB), a system information block type 1 (SIB1), and other SIBs excluding an Earthquake and Tsunami Warning System (ETWS) SIB(s) and Commercial Mobile Alert Service (CMAS) SIBs.
Example embodiment 38: The method of Example embodiment 35, wherein the notification information is separate from an indication, included in the short message, the indication indicating a change on the ETWS SIB(s) or the CMAS SIBs.
Example embodiment 39: The method of Example embodiment 35, wherein the at least one cell status is a cell barring status indicating whether or not the cell is barred for the UE.
Example embodiment 40: The method of Example embodiment 39, wherein the cell barring status is included in a Master Information Block (MIB).
Example embodiment 41: The method of Example embodiment 35, wherein the at least one cell status is an IAB support status, the IAB support status indicating whether: the cell supports IAB and the cell is also considered as a candidate for the child IAB node, or the cell does not support IAB and/or the cell is barred for the child IAB node.
Example embodiment 42: The method of Example embodiment 41, wherein the IAB support status is included in a system information block type 1 (SIB1).
Example embodiment 43: The method of Example embodiment 35, wherein the notification information comprises a first information element indicating whether or not there is a change on the system information, and a second information element indicating whether or not to acquire the system information immediately.
Example embodiment 44: The method of Example embodiment 35, wherein the notification information comprises a first information element indicating whether or not to acquire the system information after a next modification period boundary, and a second information element indicating whether or not to acquire the system information immediately.
Example embodiment 45: An integrated access and backhaul (IAB) node comprising a first radio interface and a second radio interface, the first radio interface being configured to establish a connection with a donor node, the second radio interface being configured to serve a cell to communicate with a wireless terminal, the IAB node comprising: processor circuitry configured to: detect a radio link failure (RLF) at the first radio interface; generate, based on the RLF, system information comprising at least one cell status indication indicating that the cell is barred and; generate, based on the at least one cell status indication, a notification message comprising notification information configured to instruct the wireless terminal to initiate a system information acquisition procedure immediately; transmitter circuitry configured to transmit, using the second interface, to the wireless terminal: the notification message; and the system information.
Example embodiment 46: The IAB node of Example embodiment 45, wherein the system information acquisition procedure is initiated in a current modification period.
Example embodiment 47: The IAB node of Example embodiment 45, wherein the notification information is separate from an indication indicating a change on system information blocks (SIBs) for Earthquake and Tsunami Warning System (ETWS) and a Commercial Mobile Alert Service (CMAS).
Example embodiment 48: The IAB node of Example embodiment 45, wherein the at least one cell status indication instructs the wireless terminal to initiate a cell selection procedure.
Example embodiment 49: A wireless terminal that communicates with an integrated access and backhaul (IAB) node via a cell served by the IAB node, the wireless terminal comprising: receiver circuitry configured to receive a notification message comprising notification information, the notification information instructing to initiate a system information acquisition procedure immediately; processor circuitry configured to initiate, based on the notification information, the system information acquisition procedure to acquire system information, the system information comprising at least one cell status indication indicating whether or not the cell is barred, wherein; in a case that the at least cell status indicates that the cell is barred, a cell selection procedure is initiated.
Example embodiment 50: The wireless terminal of Example embodiment 49, wherein the acquisition procedure is initiated in a current modification period.
Example embodiment 51: The wireless terminal of Example embodiment 49, wherein the notification information is separate from an indication indicating a change on system information blocks (SIBs) for Earthquake and Tsunami Warning System (ETWS) and a Commercial Mobile Alert Service (CMAS).
Example embodiment 52: The wireless terminal of Example embodiment 49, wherein the notification information further indicates that the IAB node has lost a connection to a donor node.
Example embodiment 53: A method for an integrated access and backhaul (IAB) node comprising a first radio interface and a second radio interface, the first radio interface being configured to establish a connection with a donor node, the second radio interface being configured to serve a cell to communicate with a wireless terminal, the method comprising: detecting a radio link failure (RLF) at the first radio interface; generating, based on the RLF, system information comprising at least one cell status indication indicating that the cell is barred and; generating, based on the at least one cell status indication, a notification message comprising notification information configured to instruct the wireless terminal to initiate a system information acquisition procedure immediately; transmitting, using the second interface, to the wireless terminal: the notification message; and, the system information.
Example embodiment 54: The method of Example embodiment 53, wherein the system information acquisition procedure is initiated in a current modification period.
Example embodiment 55: The method of Example embodiment 53, wherein the notification information is separate from an indication indicating a change on system information blocks (SIBs) for Earthquake and Tsunami Warning System (ETWS) and a Commercial Mobile Alert Service (CMAS).
Example embodiment 56: The method of Example embodiment 53, wherein the at least one cell status indication instructs the wireless terminal to initiate a cell selection procedure.
Example embodiment 57: A method for a wireless terminal that communicate with an integrated access and backhaul (IAB) node, the method comprising: receiving a notification message comprises notification information, the notification information instructing to initiate a system information acquisition procedure immediately; initiating, based on the notification information, a system information acquisition procedure to acquire system information, the system information comprising at least one cell status indication indicating whether or not the cell is barred, wherein; in a case that the at least cell status indicates that the cell is barred, a cell selection procedure is initiated.
Example embodiment 58: The method of Example embodiment 57, wherein the acquisition procedure is initiated in a current modification period.
Example embodiment 59: The method of Example embodiment 57, wherein the notification information is separate from an indication indicating a change on system information blocks (SIBs) for Earthquake and Tsunami Warning System (ETWS) and a Commercial Mobile Alert Service (CMAS).
Example embodiment 60: The method of Example embodiment 57, wherein the notification information further indicates that the IAB node has lost a connection to a donor node.
Although the description above contains many specificities, these should not be construed as limiting the scope of the technology disclosed herein but as merely providing illustrations of some of the presently preferred embodiments of the technology disclosed herein. Thus the scope of the technology disclosed herein should be determined by the appended claims and their legal equivalents. Therefore, it will be appreciated that the scope of the technology disclosed herein fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the technology disclosed herein is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” The above-described embodiments could be combined with one another. All structural, chemical, and functional equivalents to the elements of the above-described preferred embodiment that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the present claims. Moreover, it is not necessary for a device or method to address each and every problem sought to be solved by the technology disclosed herein, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims.
Filing Document | Filing Date | Country | Kind |
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PCT/JP2021/007807 | 3/2/2021 | WO |
Number | Date | Country | |
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62988246 | Mar 2020 | US |