Uplink-centric handover in a wireless multi-hop network

A child node in a wireless multi-hop network may receive a configuration for transmission of an uplink reference signal for a handover procedure; transmit the uplink reference signal according to the configuration; and receive a handover command or monitor for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for uplink-centric handover in a wireless multi-hop network.

BACKGROUND

SUMMARY

In some aspects, a method of wireless communication, performed by a child node in a wireless multi-hop network, may include receiving a configuration for transmission of an uplink reference signal for a handover procedure; transmitting the uplink reference signal according to the configuration; and receiving a handover command or monitoring for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal.

In some aspects, a method of wireless communication, performed by a neighbor node in a wireless multi-hop network, may include receiving a configuration for reception of an uplink reference signal for a handover procedure; monitoring for the uplink reference signal according to the configuration; and transmitting a measurement report to a control node in the wireless multi-hop network or modifying a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal.

In some aspects, a method of wireless communication, performed by a control node in a wireless multi-hop network, may include transmitting, to a child node in the wireless multi-hop network, a transmission configuration for transmission of an uplink reference signal for a handover procedure; transmitting, to a neighbor node in the wireless multi-hop network, a reception configuration for reception of the uplink reference signal for the handover procedure; receiving a measurement report based at least in part on the uplink reference signal for the handover procedure; and initiating the handover procedure based at least in part on receiving the measurement report.

In some aspects, a child node for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive a configuration for transmission of an uplink reference signal for a handover procedure; transmit the uplink reference signal according to the configuration; and receive a handover command or monitor for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal.

In some aspects, a neighbor node for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive a configuration for reception of an uplink reference signal for a handover procedure; monitor for the uplink reference signal according to the configuration; and transmit a measurement report to a control node in the wireless multi-hop network or modify a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal.

In some aspects, a control node for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to transmit, to a child node in the wireless multi-hop network, a transmission configuration for transmission of an uplink reference signal for a handover procedure; transmit, to a neighbor node in the wireless multi-hop network, a reception configuration for reception of the uplink reference signal for the handover procedure; receive a measurement report based at least in part on the uplink reference signal for the handover procedure; and initiate the handover procedure based at least in part on receiving the measurement report.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a child node, may cause the one or more processors to: receive a configuration for transmission of an uplink reference signal for a handover procedure; transmit the uplink reference signal according to the configuration; and receive a handover command or monitor for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a neighbor node, may cause the one or more processors to: receive a configuration for reception of an uplink reference signal for a handover procedure; monitor for the uplink reference signal according to the configuration; and transmit a measurement report to a control node in the wireless multi-hop network or modify a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a control node, may cause the one or more processors to: transmit, to a child node in the wireless multi-hop network, a transmission configuration for transmission of an uplink reference signal for a handover procedure; transmit, to a neighbor node in the wireless multi-hop network, a reception configuration for reception of the uplink reference signal for the handover procedure; receive a measurement report based at least in part on the uplink reference signal for the handover procedure; and initiate the handover procedure based at least in part on receiving the measurement report.

In some aspects, an apparatus for wireless communication may include means for receiving a configuration for transmission of an uplink reference signal for a handover procedure; means for transmitting the uplink reference signal according to the configuration; and means for receiving a handover command or means for monitoring for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal.

In some aspects, an apparatus for wireless communication may include means for receiving a configuration for reception of an uplink reference signal for a handover procedure; means for monitoring for the uplink reference signal according to the configuration; and means for transmitting a measurement report to a control node in the wireless multi-hop network or modifying a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal.

In some aspects, an apparatus for wireless communication may include means for transmitting, to a child node in the wireless multi-hop network, a transmission configuration for transmission of an uplink reference signal for a handover procedure; means for transmitting, to a neighbor node in the wireless multi-hop network, a reception configuration for reception of the uplink reference signal for the handover procedure; means for receiving a measurement report based at least in part on the uplink reference signal for the handover procedure; and means for initiating the handover procedure based at least in part on receiving the measurement report.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, child node, neighbor node, control node, integrated access and backhaul (IAB) node, IAB donor, central unit, and/or processing system as substantially described herein with reference to and as illustrated by the accompanying drawings and specification.

DETAILED DESCRIPTION

Controller/processor240of base station110, controller/processor280of UE120, and/or any other component(s) ofFIG.2may perform one or more techniques associated with uplink-centric handover in a wireless multi-hop network, as described in more detail elsewhere herein. For example, controller/processor240of base station110, controller/processor280of UE120, and/or any other component(s) ofFIG.2may perform or direct operations of, for example, process900ofFIG.9, process1000ofFIG.10, process1100ofFIG.11, and/or other processes as described herein. Memories242and282may store data and program codes for base station110and UE120, respectively. In some aspects, memory242and/or memory282may comprise a non-transitory computer-readable medium storing one or more instructions for wireless communication. For example, the one or more instructions, when executed by one or more processors of the base station110and/or the UE120, may perform or direct operations of, for example, process900ofFIG.9, process1000ofFIG.10, process1100ofFIG.11, and/or other processes as described herein. A scheduler246may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, the components described in connection with network controller130and/or base station110may be included in a central unit (CU) of an IAB donor, the components described in connection with base station110may be included in a distributed unit (DU) of an IAB donor and/or an IAB node, and/or the components described in connection with UE120may be included in a mobile termination (MT) of an IAB node.

In some aspects, a child node (e.g., an IAB node, a UE120, and/or the like) in a wireless multi-hop network may include means for receiving a configuration for transmission of an uplink reference signal for a handover procedure; means for transmitting the uplink reference signal according to the configuration; means for receiving a handover command or means for monitoring for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal; and/or the like. In some aspects, such means may include one or more components of UE120(which may correspond to an MT of an IAB node) described in connection withFIG.2, such as controller/processor280, transmit processor264, TX MIMO processor266, MOD254, antenna252, DEMOD254, MIMO detector256, receive processor258, and/or the like.

In some aspects, a neighbor node (e.g., an IAB node) in a wireless multi-hop network may include means for receiving a configuration for reception of an uplink reference signal for a handover procedure; means for monitoring for the uplink reference signal according to the configuration; means for transmitting a measurement report to a control node in the wireless multi-hop network or modifying a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal; and/or the like. In some aspects, such means may include one or more components of base station110(which may correspond to a DU of the neighbor node) described in connection withFIG.2, such as antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or the like.

In some aspects, a control node (e.g., an IAB donor, an IAB node, and/or the like) in a wireless multi-hop network may include means for transmitting, to a child node in the wireless multi-hop network, a transmission configuration for transmission of an uplink reference signal for a handover procedure; means for transmitting, to a neighbor node in the wireless multi-hop network, a reception configuration for reception of the uplink reference signal for the handover procedure; means for receiving a measurement report based at least in part on the uplink reference signal for the handover procedure; means for initiating the handover procedure based at least in part on receiving the measurement report; and/or the like. In some aspects, such means may include one or more components of base station110and/or network controller130(one or both of which may correspond to the control node) described in connection withFIG.2, such as antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, controller/processor290, memory292, communication unit294, and/or the like.

FIG.3is a diagram illustrating examples300of radio access networks, in accordance with various aspects of the disclosure.

As shown by reference number305, a traditional (e.g., 3G, 4G, LTE, and/or the like) radio access network may include multiple base stations310(e.g., access nodes (AN)), where each base station310communicates with a core network via a wired backhaul link315, such as a fiber connection. A base station310may communicate with a UE320via an access link325, which may be a wireless link. In some aspects, a base station310shown inFIG.3may correspond to a base station110shown inFIG.1. Similarly, a UE320shown inFIG.3may correspond to a UE120shown inFIG.1.

As shown by reference number330, a radio access network may include a wireless backhaul network, sometimes referred to as an integrated access and backhaul (IAB) network. An IAB network is a type of wireless multi-hop network. In an IAB network, at least one base station is an anchor base station335that communicates with a core network via a wired backhaul link340, such as a fiber connection. An anchor base station335may also be referred to as an IAB donor (or IAB-donor). The IAB network may include one or more non-anchor base stations345, sometimes referred to as relay base stations, IAB nodes (or IAB-nodes), and/or the like. The non-anchor base station345may communicate directly with or indirectly with (e.g., via one or more non-anchor base stations345) the anchor base station335via one or more backhaul links350to form a backhaul path (or route) to the core network for carrying backhaul traffic. Backhaul link350may be a wireless link. Anchor base station(s)335and/or non-anchor base station(s)345may communicate with one or more UEs355via access links360, which may be wireless links for carrying access traffic. In some aspects, an anchor base station335and/or a non-anchor base station345shown inFIG.3may correspond to a base station110shown inFIG.1. Similarly, a UE355shown inFIG.3may correspond to a UE120shown inFIG.1.

As shown by reference number365, in some aspects, a radio access network that includes an IAB network may utilize millimeter wave technology and/or directional communications (e.g., beamforming, precoding and/or the like) for communications between base stations and/or UEs (e.g., between two base stations, between two UEs, and/or between a base station and a UE). For example, wireless backhaul links370between base stations may use millimeter waves to carry information and/or may be directed toward a target base station using beamforming, precoding, and/or the like. Similarly, the wireless access links375between a UE and a base station may use millimeter waves and/or may be directed toward a target wireless node (e.g., a UE and/or a base station). In this way, inter-link interference may be reduced.

The configuration of base stations and UEs inFIG.3is shown as an example, and other examples are possible. For example, one or more base stations illustrated inFIG.3may be replaced by one or more UEs that communicate via a UE-to-UE access network (e.g., a peer-to-peer network, a device-to-device network, and/or the like). In this case, an anchor node may refer to a UE that is directly in communication with a base station (e.g., an anchor base station or a non-anchor base station).

FIG.4is a diagram illustrating an example400of an IAB network architecture, in accordance with various aspects of the disclosure.

As shown inFIG.4, an IAB network may include an IAB donor405(shown as IAB-donor405) that connects to a core network via a wired connection (shown as a wireline backhaul). For example, an Ng interface of an IAB donor405may terminate at a core network. Additionally, or alternatively, an IAB donor405may connect to one or more devices of the core network that provide an access and mobility management function (e.g., AMF). In some aspects, an IAB donor405may include a base station110, such as an anchor base station, as described above in connection withFIG.3. As shown, an IAB donor405may include a central unit (CU), which may perform access node controller (ANC) functions, AMF functions, and/or the like. The CU may configure a distributed unit (DU) of the IAB donor405and/or may configure one or more IAB nodes410(e.g., an MT and/or a DU of an IAB node410) that connect to the core network via the IAB donor405. Thus, a CU of an IAB donor405may control and/or configure the entire IAB network that connects to the core network via the IAB donor405, such as by using control messages and/or configuration messages (e.g., a radio resource control (RRC) configuration message and/or the like). In some aspects, a control and/or configuration message may be carried via an F1 application protocol (F1-AP) interface.

As further shown inFIG.4, the IAB network may include IAB nodes410(shown as IAB-node1and IAB-node2) that connect to the core network via the IAB donor405. As shown, an IAB node410may include mobile termination (MT) functions (sometimes referred to as UE functions (UEF)), and may include DU functions (sometimes referred to as access node functions (ANF)). The MT functions of an IAB node410(e.g., a child node) may be controlled and/or scheduled by another IAB node410(e.g., a parent node of the child node) and/or by an IAB donor405. The DU functions of an IAB node410(e.g., a parent node) may control and/or schedule other IAB nodes410(e.g., child nodes of the parent node) and/or UEs120. Thus, a DU may be referred to as a scheduling node or a scheduling component, and an MT may be referred to as a scheduled node or a scheduled component. In some aspects, an IAB donor405may include DU functions and not MT functions. That is, an IAB donor405may configure, control, and/or schedule communications of IAB nodes410and/or UEs120. A UE120may include only MT functions, and not DU functions. That is, communications of a UE120may be controlled and/or scheduled by an IAB donor405and/or an IAB node410(e.g., a parent node of the UE120).

When a first node controls and/or schedules communications for a second node (e.g., when the first node provides DU functions for the second node's MT functions), the first node may be referred to as a parent node of the second node, and the second node may be referred to as a child node of the first node. A child node of the second node may be referred to as a grandchild node of the first node. Thus, a DU function of a parent node may control and/or schedule communications for child nodes of the parent node. A parent node may be an IAB donor405or an IAB node410, and a child node may be an IAB node410or a UE120. Communications of an MT function of a child node may be controlled and/or scheduled by a parent node of the child node.

As further shown inFIG.4, a link between a UE120(e.g., which only has MT functions, and not DU functions) and an IAB donor405, or between a UE120and an IAB node410, may be referred to as an access link415. Access link415may be a wireless access link that provides a UE120with radio access to a core network via an IAB donor405, and optionally via one or more IAB nodes410. Thus, the network illustrated inFIG.4may be referred to as a wireless multi-hop network.

As further shown inFIG.4, a link between an IAB donor405and an IAB node410or between two IAB nodes410may be referred to as a backhaul link420. Backhaul link420may be a wireless backhaul link that provides an IAB node410with radio access to a core network via an IAB donor405, and optionally via one or more other IAB nodes410. In some aspects, a backhaul link420may be a primary backhaul link or a secondary backhaul link (e.g., a backup backhaul link). In some aspects, a secondary backhaul link may be used if a primary backhaul link fails, becomes congested, becomes overloaded, and/or the like. As used herein, a node or a wireless node may refer to an IAB donor405or an IAB node410.

In an IAB network, network resources for wireless communications (e.g., time resources, frequency resources, spatial resources, and/or the like) may be shared between a parent link425of an IAB node410(shown as link420/425for IAB-node1) and a child link430of the IAB node410(shown as link420/430for IAB-node1). When an IAB node410uses time division multiplexing (TDM) between a parent link425and a child link430, the IAB node410is subject to a half duplex constraint, meaning that the IAB node410cannot transmit and receive information at the same time (e.g., cannot concurrently communicate via a parent link425of the IAB node410and a child link430of the IAB node410). This constraint may lead to high latency for communications.

To reduce latency, increase robustness, and expand coverage of an IAB network, the IAB network may be over-deployed. For example, there may be multiple IAB donors405and/or IAB nodes410with overlapping coverage, there may be multiple routes from a particular UE120and/or IAB node410to another IAB node and/or to the IAB donor405, and/or the like. For example, because millimeter wave communications have high signal attenuation during propagation, IAB nodes410with overlapping coverage may be deployed to expand coverage in the IAB network and mitigate such signal attenuation. Furthermore, because millimeter wave communications are susceptible to link blockage and link failure, IAB nodes410with overlapping coverage may be deployed to improve robustness of the IAB network.

In an over-deployed IAB network, different IAB nodes410may have different operating modes depending on, for example, a number of child nodes and/or UEs120served by the IAB node410, an amount of traffic served by the IAB node410, a power status of the IAB node410(e.g., whether the IAB node410is operating using battery power or alternating current (AC) power, a remaining battery life of the IAB node410, and/or the like), a power saving mode of the IAB node410, and/or the like. To conserve energy and battery power, an IAB node410may enter an operating mode with low energy consumption when network activity (e.g., a number of child nodes and/or UEs120to be served, an amount of network traffic, and/or the like) in a coverage area of the IAB node410is low and/or if other IAB nodes410in that coverage area are capable of handling the network activity. Conversely, if network activity in a coverage area of an IAB node410is high and/or if other IAB nodes410in that coverage area are not capable of handling the network activity (or are not present in the coverage area), then the IAB node410may enter an operating mode with high energy consumption.

During a handover procedure, a UE120and/or a child node may be handed over from a serving node (e.g., a first parent node) to a target node (e.g., a second parent node). During a cell selection procedure and/or a cell reselection procedure, a target node may be selected to serve a UE120and/or a child node. In an over-deployed IAB network, there may be multiple neighbor nodes that satisfy a handover condition (e.g., criteria) and/or a cell selection condition, and that are candidates for the target node. However, the multiple neighbor nodes may have different operating modes, such that selection of a first neighbor node over a second neighbor node provides poorer performance even if the first neighbor node is associated with better parameters (e.g., an RSRP parameter and/or the like) for handover or cell selection as compared to the second neighbor node. For example, the first neighbor node may be in a power saving mode, may be operating using battery power, may have low remaining battery life, may have a long route to an IAB donor405, and/or the like. In such cases, selection of the first neighbor node using traditional procedures and/or parameters for handover or cell selection would result in worse performance than selection of the second neighbor node. Some techniques and apparatuses described herein account for operating modes of neighbor nodes when performing a handover procedure and/or a cell selection procedure (e.g., including a cell reselection procedure), thereby improving performance of the IAB network.

FIG.5is a diagram illustrating an example500of a downlink-centric handover procedure in an IAB network, in accordance with various aspects of the present disclosure.

As shown inFIG.5, a downlink-centric handover procedure in an IAB network may involve a child node505(e.g., a UE, an IAB node, and/or the like), a serving node510that serves the child node505prior to handover, a neighbor node515(e.g., selected from a set of neighbor nodes) that serves the child node505as a target node after handover, and a control node520. The control node520may communicate with the serving node510and the neighbor node515to initiate, set up, and/or otherwise assist in or instruct on the handover procedure. In some aspects, the control node520may be the same as the serving node510(e.g., operations described herein as being performed by the control node520may be performed by the serving node510). In some aspects, the control node520may be a parent node of the serving node510and/or a parent node of the neighbor node515. In some aspects, the control node520may be an IAB donor405(e.g., a CU of an IAB donor405).

As shown by reference number525, in a downlink-centric handover procedure, the child node505may receive one or more downlink (DL) reference signals from a set of neighbor nodes including the neighbor node515. The one or more downlink reference signals may include, for example, one or more synchronization signal blocks (SSBs), one or more synchronization signal (SS) and/or physical broadcast channel (SS/PBCH) blocks, one or more channel state information reference signals (CSI-RSs), and/or the like. The child node505may perform measurements on the received downlink reference signals, such as RSRP measurements, RSRQ measurements, RSSI measurements, signal-to-interference-plus-noise ratio (SINR) measurements, and/or the like.

As shown by reference number530, the child node505may report the measurements of the downlink reference signals of the set of neighbor nodes to the serving node510, such as in a measurement report. As shown by reference number535, the serving node510may provide the measurement report to the control node520responsible for selecting a neighbor node, from the set of neighbor nodes, as a target node for handover. As shown by reference number540, the control node520may select the neighbor node515(e.g., if a handover condition is satisfied), and may communicate with the serving node510and the neighbor node515to initiate, set up, and/or otherwise assist in or instruct on the handover procedure.

As shown by reference number545, the serving node510may transmit a handover command to the child node505. The handover command may indicate the neighbor node515to which the child node505is to be handed over (e.g., as instructed by the control node520to the serving node510). As shown by reference number550, the child node505may perform a random access channel (RACH) procedure to connect to the neighbor node515based at least in part on receiving the handover command that identifies the neighbor node515. After the handover procedure is complete, the child node505may be served by the neighbor node515and not the serving node510.

The handover procedure shown inFIG.5is an example of a downlink-centric handover procedure, where handover is initiated based at least in part on a downlink reference signal transmitted by a neighbor node and monitored by a child node (e.g., as described above in connection with reference number525). In some cases, using a downlink-centric handover procedure may be inefficient. For example, when an IAB network is over-deployed, the number of child nodes expected to undergo handover (e.g., in a particular time period) may be less than the number of neighbor nodes that are potential candidates to be a target node for the handover. Additionally, or alternatively, one or more neighbor nodes may be operating in a low energy consumption state due to serving a small number of child nodes and/or a small amount of network traffic, and thus the number of child nodes expected to undergo handover (e.g., in a particular time period) may be less than the number of neighbor nodes that are potential candidates to be a target node for the handover.

In these example cases, an uplink-centric handover procedure may be more efficient than a downlink-centric handover procedure. In an uplink-centric handover procedure, handover may be initiated based at least in part on an uplink reference signal transmitted by a child node and monitored by one or more neighbor nodes. Using an uplink-centric handover procedure may conserve network resources as compared to a downlink-centric handover procedure, due to a number of uplink reference signals to be transmitted by child nodes and monitored by neighbor nodes in an uplink-centric handover procedure being less than a number of downlink reference signals to be transmitted by neighbor nodes and monitored by child nodes in a downlink-centric handover procedure. Furthermore, a neighbor node in a power saving mode may consume less power in an uplink-centric handover procedure because less power is needed for the neighbor node to receive a reference signal as compared to transmitting a reference signal. In some cases, such power consumption can be further reduced by configuring the child node and the neighbor node regarding transmission and reception of uplink reference signals. Some techniques and apparatuses described herein may be used to achieve uplink-centric handover.

FIG.6is a diagram illustrating an example600of various operating modes of nodes in an IAB network, in accordance with various aspects of the present disclosure.

As shown inFIG.6, different nodes (e.g., IAB nodes410) in an IAB network may operate in different operating modes (e.g., at a given point in time), sometimes referred to as power saving modes. For example, a serving node605of a child node (e.g., a UE/MT) may operate in a high energy consumption state (e.g., with a power saving mode disabled, with one or more power saving mode operations disabled, and/or the like). The serving node605may operate in the high energy consumption state due to serving a number (e.g., a quantity) of child nodes that satisfies a threshold, due to serving an amount of network traffic that satisfies a threshold, due to being powered by AC power, due to having a remaining amount of battery life that satisfies a threshold, and/or the like. In the high energy consumption state, the serving node605may be fully active, may have more features enabled than a node in a lower energy consumption state, may perform one or more operations (e.g., transmissions, reference signal transmissions, paging, and/or the like) more frequently than a node in a lower energy consumption state, and/or the like.

As another example, a first neighbor node610may operate in a low energy consumption state (e.g., with a power saving mode enabled, with one or more power saving mode operations enabled, and/or the like). The first neighbor node610may operate in the low energy consumption state due to serving a number of child nodes that does not satisfy a threshold, due to serving an amount of network traffic that does not satisfy a threshold, due to being powered by battery power, due to having a remaining amount of battery life that does not satisfy a threshold, and/or the like. In the low energy consumption state, the first neighbor node610may be in a deep sleep mode and/or a power saving mode, may have fewer features enabled than a node in a higher energy consumption state, may perform one or more operations (e.g., transmissions, reference signal transmissions, paging, and/or the like) less frequently than a node in a higher energy consumption state, may operate with limited service (e.g., may provide only emergency service), and/or the like. In some aspects, in the low energy consumption state, the first neighbor node610may be powered off (e.g., for battery charging). In some aspects, the operating mode may include a transmission mode, and a neighbor node in a low energy consumption state may send transmissions (e.g., downlink reference signals) less frequently as compared to a high energy consumption state.

As further shown inFIG.6, different neighbor nodes615,620,625, and630may operate in different operating modes within a range of operating modes. For example, different operating modes may correspond to serving different numbers of child nodes (e.g., a number of child nodes that falls within a threshold range, that is greater than a threshold, that is less than a threshold, and/or the like), due to serving different amounts of network traffic (e.g., an amount of network traffic that falls within a threshold range, that is greater than a threshold, that is less than a threshold, and/or the like), due to being powered by battery power or by AC power, due to having different amounts of remaining battery life (e.g., an amount of remaining battery life that falls within a threshold range, that is greater than a threshold, that is less than a threshold, and/or the like), due to being in a charging state or not being in a charging state, and/or the like.

As described above, a neighbor node may operate in a low energy consumption state due to serving a small number of child nodes and/or a small amount of network traffic. As a result, the number of child nodes expected to undergo handover to or from the neighbor node (e.g., while the neighbor node is operating in the low energy consumption state) may be less than the number of neighbor nodes that are potential candidates to be a target node for the handover. Thus, as described above, network resources and power consumption of neighbor nodes may be conserved by using an uplink-centric handover procedure.

FIG.7is a diagram illustrating an example700of uplink-centric handover in a wireless multi-hop network, in accordance with various aspects of the present disclosure.

As shown inFIG.7, a child node705(e.g., a UE, an IAB node410, and/or the like) may be served by a serving node710(e.g., a parent node). The child node705may transmit uplink reference signals to a set of neighbor nodes715(referred to collectively as neighbor nodes715and individually as neighbor node715). The serving node710and/or one or more neighbor nodes715may be controlled by a control node720.

The nodes ofFIG.7may correspond to nodes as described above in connection withFIG.5. Thus, as described above in connection withFIG.5, the child node705may include a UE, an IAB node (e.g., an MT function of an IAB node, a DU function of an IAB node, and/or the like), and/or the like. The serving node710may include an IAB node410(e.g., having a DU function for scheduling communications with the child node705), an IAB donor405(e.g., having a CU), a parent node of the child node705, and/or the like. The control node720may be the same as the serving node710(e.g., operations described herein as being performed by the control node720may be performed by the serving node710), may be a parent node of the serving node710(and/or of one or more neighbor nodes715), and/or may be an IAB donor405(e.g., a CU of an IAB donor405).

As shown by reference number725, the control node720may transmit, to the child node705, a configuration for transmission of an uplink reference signal for a handover procedure. This configuration may be referred to as a transmission configuration. The transmission configuration may indicate one or more parameters for transmission of the uplink reference signal. For example, the transmission configuration may indicate one or more resources for transmission of the uplink reference signal (e.g., one or more time domain resources, one or more frequency domain resources, one or more spatial domain resources, and/or the like), a transmit power for transmission of the uplink reference signal, a beam configuration for transmission of the uplink reference signal (e.g., one or more beams via which the uplink reference signal is to be transmitted, a beam-sweeping pattern to be used for transmission of the uplink reference signal, a beam width, a number of beams, and/or the like), and/or the like. The transmission configuration may be transmitted via a radio resource control (RRC) message (e.g., when the uplink reference signal is transmitted by a UE or an MT function), an F1 application protocol (F1-AP) interface (e.g., when the uplink reference signal transmitted by a DU function), and/or the like.

As shown by reference number730, the control node720may transmit, to one or more neighbor nodes715, a configuration for reception of an uplink reference signal for a handover procedure. This configuration may be referred to as a reception configuration. The reception configuration may indicate one or more parameters for reception of the uplink reference signal. For example, the reception configuration may indicate one or more resources for monitoring for the uplink reference signal (e.g., one or more time domain resources, one or more frequency domain resources, one or more spatial domain resources, and/or the like), a beam configuration for monitoring for the uplink reference signal (e.g., one or more beams on which the uplink reference signal is to be monitored, a beam-sweeping pattern to be used for monitoring for the uplink reference signal, a beam width, a number of beams, and/or the like), a power saving mode configuration for a neighbor node715being configured, and/or the like. The reception configuration may be transmitted via an RRC message, an F1-AP interface, and/or the like.

In some aspects, the power saving mode configuration may indicate an active time period for the neighbor node715(e.g., during which the neighbor node715is in an active state, an awake state, a high energy consumption state, a high power state, and/or the like), an inactive time period for the neighbor node715(e.g., during which the neighbor node715is in an inactive state, a sleep state, a low energy consumption state, a low power state, and/or the like), an operating mode for the neighbor node715, and/or the like.

In some aspects, the control node720may determine one or more parameters of the transmission configuration and/or the reception configuration based at least in part on information received from the child node705and/or a neighbor node715. For example, the control node720may configure a transmit power for an uplink reference signal based at least in part on a location of the child node705and/or one or more locations corresponding to one or more neighbor nodes715. In some aspects, the control node720may configure the transmit power such that the uplink reference signal is likely to propagate to the neighbor node(s)715. Additionally, or alternatively, the control node720may align a transmission time of the uplink reference signal (e.g., a time domain resource for transmission of the uplink reference signal by the child node705) and an active time period of the neighbor node715(e.g., a time domain resource during which the neighbor node715is in an active state and able to monitor for and/or receive the uplink reference signal). Additionally, or alternatively, the control node720may align a transmit beam direction, used by the child node705to transmit the uplink reference signal, and a receive beam direction used by the neighbor node715to monitor for the uplink reference signal.

As shown by reference number735, the child node705may transmit one or more uplink reference signals according to the transmission configuration. For example, the child node705may transmit an uplink reference signal in one or more resources indicated by the transmission configuration, using a transmit power indicated by the transmission configuration, via one or more beams indicated by the transmission configuration (e.g., using a particular beam, a particular set of beams, a beam-sweeping pattern, and/or the like), and/or the like.

In some aspects, the uplink reference signal is a sounding reference signal (SRS). For example, the child node705may be a UE and/or may include an MT function of an IAB node. In this case, the UE or the MT function of the IAB node may transmit an SRS as the uplink reference signal. When the uplink reference signal is an SRS, the transmission configuration for configuring the SRS (e.g., an SRS configuration) may be transmitted via an RRC message, such as an RRC configuration message, an RRC reconfiguration message, and/or the like.

In some aspects, the uplink reference signal is an SSB or a CSI-RS. For example, the child node705may include a DU function of an IAB node. In this case, the DU function of the IAB node may transmit an SSB and/or a CSI-RS as the uplink reference signal. When the uplink reference signal is an SSB and/or a CSI-RS, the transmission configuration for configuring the SSB and/or the CSI-RS (e.g., an SSB configuration and/or a CSI-RS configuration) may be transmitted via an F1-AP interface between the control node720and the child node705(e.g., the DU function of the child node705).

In some aspects, the child node705may transmit an uplink reference signal in multiple directions, such as by using beam-sweeping. In some aspects, the transmission configuration may indicate a beam-sweeping pattern to be used by the child node705to transmit the uplink reference signal, and the child node705may transmit the uplink reference signal according to the beam-sweeping pattern. In some cases, when transmitting the uplink reference signal, the child node705may transmit the uplink reference signal in multiple directions (e.g., over time) without waiting for a handover command between different transmissions of the uplink reference signal. Alternatively, the child node705may transmit the uplink reference signal in a first direction (or a first set of directions), and may then wait for a handover command (e.g., as described in more detail below in connection with reference number760). If the child node705does not receive a handover command within a threshold amount of time, then the child node705may transmit the uplink reference signal in a second direction (or a second set of directions), and so on.

As shown by reference number740, a neighbor node715may monitor for the uplink reference signal. In some aspects, the neighbor node715may monitor for the uplink reference signal according to the reception configuration. For example, the neighbor node715may monitor for an uplink reference signal in one or more resources indicated by the reception configuration, via one or more beams indicated by the reception configuration (e.g., using a particular beam, a particular set of beams, a beam-sweeping pattern, and/or the like), during an active time period of the neighbor node715, and/or the like.

As shown by reference number745, a neighbor node715may transmit a measurement report to the control node720based at least in part on receiving one or more uplink reference signals from the child node705. The measurement report may indicate a parameter to be used for a handover decision, such as an RSRP parameter, an RSRQ parameter, an RSSI parameter, an SINR parameter, and/or the like. In some aspects, multiple neighbor nodes may transmit respective measurement reports to the control node720based at least in part on reception of an uplink reference signal from the child node705.

In some aspects, the control node720may transmit, to the neighbor node715, a measurement and reporting configuration that indicates a condition for transmitting the measurement report. In this case, the neighbor node715may transmit the measurement report to the control node720based at least in part on a determination that the condition is satisfied. For example, the condition may be that the measurement report is to be transmitted if an RSRP parameter, of an uplink reference signal transmitted by the child node705and measured by the neighbor node715, satisfies a threshold (e.g., a threshold indicated in the measurement and reporting configuration). In this case, if the neighbor node715determines that a measured RSRP parameter of the uplink reference signal satisfies the threshold, then the neighbor node715may transmit a measurement report, associated with the uplink reference signal and the child node705, to the control node720. In some aspects, the measurement and reporting configuration may be transmitted via an RRC message, via an F1-AP interface, and/or the like.

As shown by reference number750, the control node720may select a target node, from a set of neighbor nodes715, based at least in part on measurement reports received from the set of neighbor nodes715(e.g., if a handover condition is satisfied). As shown by reference number755, the control node720may initiate the handover procedure based at least in part on selecting a neighbor node715as the target node for handover. For example, the control node720may communicate with the serving node710and the neighbor node715to initiate, set up, and/or otherwise assist in or instruct on the handover procedure. For example, the control node720may transmit a handover request to the serving node710and/or may transmit a handover request to the neighbor node715selected as the target node. In some aspects, rather than setting up handover based at least in part on receiving one or more measurement reports, the control node720may instruct one or more neighbor nodes715, from which the measurement report(s) are received, to modify a transmission mode (e.g., for downlink reference signals), as described in more detail below in connection withFIG.8.

As shown by reference number760, the control node720may transmit (e.g., via the serving node710) a handover command to the child node705. The handover command may indicate the neighbor node715to which the child node705is to be handed over (e.g., as instructed by the control node720to the serving node710). In some aspects, the child node705may receive the handover command without transmitting a measurement report to the control node720or the serving node710(e.g., because the measurement report is transmitted by one or more neighbor nodes715for the uplink-centric handover procedure rather than by the child node705for a downlink-centric handover procedure). As shown by reference number765, the child node705may perform a RACH procedure to connect to the neighbor node715(e.g., by transmitting a RACH preamble to the neighbor node715) based at least in part on receiving the handover command that identifies the neighbor node715. After the handover procedure is complete, the child node705may be served by the neighbor node715and not the serving node710.

By using an uplink-centric handover procedure rather than a downlink-centric handover procedure, network resources may be conserved, resources of one or more neighbor nodes715may be conserved, and/or the like, as described above. In some aspects, the control node720may configure the child node705and/or the one or more neighbor nodes715regarding whether to use an uplink-centric handover procedure (e.g., described in connection withFIGS.7and8) or a downlink-centric handover procedure (e.g., described in connection withFIG.5).

FIG.8is a diagram illustrating an example800of uplink-centric handover in a wireless multi-hop network, in accordance with various aspects of the present disclosure.

As shown inFIG.8, a child node705(e.g., a UE, an IAB node410, and/or the like) may be served by a serving node710(e.g., a parent node). The child node705may transmit uplink reference signals to a set of neighbor nodes715(referred to collectively as neighbor nodes715and individually as neighbor node715). The serving node710and/or one or more neighbor nodes715may be controlled by a control node720. The nodes ofFIG.8may correspond to nodes as described above in connection withFIG.7.

As shown by reference number805, the control node720may transmit, to the child node705, a transmission configuration for transmission of an uplink reference signal for a handover procedure, as described above in connection with reference number725ofFIG.7. As shown by reference number810, the control node720may transmit, to one or more neighbor nodes715, a reception configuration for reception of an uplink reference signal for a handover procedure, as described above in connection with reference number730ofFIG.7.

As shown by reference number815, the child node705may transmit one or more uplink reference signals according to the transmission configuration, as described above in connection with reference number735ofFIG.7. In some cases, when transmitting the uplink reference signal, the child node705may transmit the uplink reference signal in multiple directions (e.g., over time) without waiting for a downlink reference signal between different transmissions of the uplink reference signal. Alternatively, the child node705may transmit the uplink reference signal in a first direction (or a first set of directions), and may then wait for a downlink reference signal (e.g., as described in more detail below in connection with reference number830). If the child node705does not receive a downlink reference signal within a threshold amount of time, then the child node705may transmit the uplink reference signal in a second direction (or a second set of directions), and so on. As shown by reference number820, a neighbor node715may monitor for the uplink reference signal, as described above in connection with reference number740ofFIG.7.

As shown by reference number825, a neighbor node715may modify a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal. For example, prior to receiving the uplink reference signal, the neighbor node715may be in a power saving mode where downlink reference signals are transmitted less frequently. After receiving the uplink reference signal, the neighbor node715may disable the power saving mode (and/or one or more functions of the power saving mode), and may transmit downlink reference signal more frequently. In some aspects, the neighbor node715may modify the transmission mode based at least in part on a determination that the uplink reference signal satisfies a condition, such as an RSRP parameter of the uplink reference signal satisfying a threshold. In some aspects, the condition may be indicated to and/or configured for the neighbor node715by the control node720(e.g., in the reception configuration). Additionally, or alternatively, the neighbor node715may transmit a measurement report to the control node720based at least in part on the uplink reference signal (as described above in connection withFIG.7), and the control node720may instruct the neighbor node715to modify the transmission mode based at least in part on the measurement report (e.g., the measurement report satisfying a condition, an RSRP parameter, indicated in the measurement report, satisfying a threshold, and/or the like).

As shown by reference number830, the neighbor node715may transmit a downlink reference signal based at least in part on modifying the transmission mode. For example, the neighbor node715may transmit the downlink reference signal more frequently as compared to a time period prior to modifying the transmission mode. The downlink reference signal may include, for example, an SSB, a CSI-RS, and/or the like. The child node705may monitor for one or more downlink reference signals based at least in part on transmitting the uplink reference signal. For example, the child node705may monitor for downlink reference signals more frequently as compared to a time period prior to transmitting the uplink reference signal. In some aspects, the periodicity of monitoring prior to transmission of the uplink reference signal and/or after transmission of the uplink reference signal may be indicated to and/or configured for the child node705by the control node720.

In some aspects, the neighbor node715may determine a transmit power for the downlink reference signal based at least in part on the uplink reference signal. For example, if the uplink reference signal is received with a lower signal power (e.g., a lower RSRP), then the neighbor node715may transmit the downlink reference signal with a higher transmit power, and if the uplink reference signal is received with a higher signal power (e.g., a higher RSRP), then the neighbor node715may transmit the downlink reference signal with a lower transmit power. In this way, the neighbor node715may conserve resources (e.g., battery power, processing resources, memory resources, and/or the like) while also facilitating successful reception of the downlink reference signal by the child node705.

Additionally, or alternatively, the neighbor node715may determine a beam for transmission of the downlink reference signal (e.g., a transmit beam) based at least in part on the uplink reference signal. For example, the neighbor node715may identify a transmit beam that corresponds to a receive beam via which the uplink reference signal was received (and/or a strongest beam via which the uplink reference signal was received), and may transmit the downlink reference signal using the transmit beam. In this way, the neighbor node715may conserve resources of the neighbor node715(e.g., battery power, processing resources, memory resources, and/or the like) and may conserve network resources by transmitting the downlink reference signal using fewer beams (e.g., a single beam or a smaller set of beams). Similarly, the child node705may determine a receive beam to be used for monitoring for a downlink reference signal based at least in part on a transmit beam used by the child node705to transmit the uplink reference signal, thereby conserving resources of the child node705(e.g., as compared to monitoring multiple beams).

Additionally, or alternatively, the neighbor node715may determine one or more resources (e.g., time domain resources, frequency domain resources, spatial domain resources, and/or the like) for transmission of the downlink reference signal based at least in part on the uplink reference signal. For example, the neighbor node715may identify one or more downlink resources based at least in part on one or more uplink resources via which the uplink reference signal was received, and may transmit the downlink reference signal using the one or more downlink resources. In this case, the child node705may monitor for the downlink reference signal on one or more resources that correspond to a resource via which the uplink reference signal is transmitted.

As shown by reference number835, the child node705may transmit a measurement report to the control node720(e.g., via the serving node710) based at least in part on measuring one or more downlink reference signals. The measurement report may include, for example, an RSRP parameter, an RSRQ parameter, an RSSI parameter, an SINR parameter, and/or the like, for a set of downlink reference signals measured by the child node705(e.g., received from one or more neighbor nodes715).

As shown by reference number840, the control node720may select a target node, from a set of neighbor nodes715, based at least in part on the measurement report received from the child node705(e.g., if a handover condition is satisfied). As shown by reference number845, the control node720may initiate the handover procedure based at least in part on selecting a neighbor node715as the target node for handover, as described above in connection with reference number755ofFIG.7.

As shown by reference number850, the control node720may transmit (e.g., via the serving node710) a handover command to the child node705, as described above in connection with reference number760ofFIG.7. As shown by reference number855, the child node705may perform a RACH procedure to connect to the neighbor node715(e.g., by transmitting a RACH preamble to the neighbor node715) based at least in part on receiving the handover command that identifies the neighbor node715. After the handover procedure is complete, the child node705may be served by the neighbor node715and not the serving node710. By using an uplink-centric handover procedure rather than a downlink-centric handover procedure, network resources may be conserved, resources of one or more neighbor nodes715may be conserved, and/or the like, as described above.

FIG.9is a diagram illustrating an example process900performed, for example, by a child node, in accordance with various aspects of the present disclosure. Example process900is an example where the child node (e.g., an IAB node410, a child node705, a UE120, a base station110, and/or the like) performs operations associated with uplink-centric handover in a wireless multi-hop network.

As shown inFIG.9, in some aspects, process900may include receiving a configuration for transmission of an uplink reference signal for a handover procedure (block910). For example, the child node (e.g., using antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, memory242, antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, memory282, and/or the like) may receive a configuration for transmission of an uplink reference signal for a handover procedure, as described above.

As further shown inFIG.9, in some aspects, process900may include transmitting the uplink reference signal according to the configuration (block920). For example, the child node (e.g., using transmit processor220, controller/processor240, memory242, transmit processor264, controller/processor280, memory282, and/or the like) may transmit the uplink reference signal according to the configuration, as described above.

As further shown inFIG.9, in some aspects, process900may include receiving a handover command or monitoring for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal (block930). For example, the child node (e.g., using antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, memory242, antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, memory282, and/or the like) may receive a handover command or monitor for a downlink reference signal for the handover procedure based at least in part on transmitting the uplink reference signal, as described above.

In a first aspect, the configuration indicates at least one of a resource for transmission of the uplink reference signal, a transmit power for transmission of the uplink reference signal, a beam configuration for transmission of the uplink reference signal, or a combination thereof.

In a second aspect, alone or in combination with the first aspect, the uplink reference signal is a sounding reference signal.

In a third aspect, alone or in combination with one or more of the first and second aspects, the uplink reference signal is transmitted by a user equipment or a mobile termination component of an integrated access and backhaul node.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the configuration is received from a control node of the wireless multi-hop network via a radio resource control message.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the uplink reference signal is a synchronization signal block or a channel state information reference signal.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the uplink reference signal is transmitted by a distributed unit component of an integrated access and backhaul node.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the configuration is received from a control node of the wireless multi-hop network via an F1 application protocol interface.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the downlink reference signal is a synchronization signal block or a channel state information reference signal.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the uplink reference signal is transmitted in multiple directions using beam-sweeping.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the uplink reference signal is transmitted in a first direction and is subsequently transmitted in a second direction based at least in part on a determination that: a handover command was not received based at least in part on transmission of the uplink reference signal in the first direction, or a downlink reference signal, for the handover procedure, that satisfies a threshold was not received based at least in part on transmission of the uplink reference signal in the first direction.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, process900includes transmitting a random access channel preamble to a target node for the handover procedure based at least in part on receiving the handover command.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, process900includes monitoring for the downlink reference signal for the handover procedure on one or more resources that correspond to a resource via which the uplink reference signal is transmitted.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the handover command is received without transmission of a measurement report for the handover procedure.

FIG.10is a diagram illustrating an example process1000performed, for example, by a neighbor node, in accordance with various aspects of the present disclosure. Example process1000is an example where the neighbor node (e.g., an IAB node410, a neighbor node715, a base station110, and/or the like) performs operations associated with uplink-centric handover in a wireless multi-hop network.

As shown inFIG.10, in some aspects, process1000may include receiving a configuration for reception of an uplink reference signal for a handover procedure (block1010). For example, the neighbor node (e.g., using antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, memory242, and/or the like) may receive a configuration for reception of an uplink reference signal for a handover procedure, as described above.

As further shown inFIG.10, in some aspects, process1000may include monitoring for the uplink reference signal according to the configuration (block1020). For example, the neighbor node (e.g., using antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, memory242, and/or the like) may monitor for the uplink reference signal according to the configuration, as described above.

As further shown inFIG.10, in some aspects, process1000may include transmitting a measurement report to a control node in the wireless multi-hop network or modifying a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal (block1030). For example, the neighbor node (e.g., using controller/processor240, memory242, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or the like) may transmit a measurement report to a control node in the wireless multi-hop network or modify a transmission mode for a downlink reference signal for the handover procedure based at least in part on receiving the uplink reference signal, as described above.

In a first aspect, the configuration for reception of the uplink reference signal indicates at least one of a power saving mode configuration for the neighbor node, a resource for monitoring for the uplink reference signal, a beam configuration for monitoring for the uplink reference signal, or a combination thereof.

In a second aspect, alone or in combination with the first aspect, process1000includes transmitting the measurement report to the control node based at least in part on a measurement and reporting configuration that indicates a condition for transmitting the measurement report.

In a third aspect, alone or in combination with one or more of the first and second aspects, the measurement and reporting configuration is received via a radio resource control message.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, process1000includes receiving a handover request from the control node based at least in part on transmitting the measurement report to the control node.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, process1000includes receiving an instruction, from the control node, to modify the transmission mode based at least in part on transmitting the measurement report to the control node.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, modifying the transmission mode for the downlink reference signal for the handover procedure comprises transmitting the downlink reference signal more frequently as compared to a time period prior to modifying the transmission mode.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the transmission mode is modified based at least in part on a determination that a condition, indicated by the control node and associated with the uplink reference signal, is satisfied.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, at least one of a transmit power for the downlink reference signal or a beam for transmission of the downlink reference signal is determined based at least in part on the uplink reference signal.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the downlink reference signal is a synchronization signal block or a channel state information reference signal.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the uplink reference signal is a sounding reference signal, a synchronization signal block, or a channel state information reference signal.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the configuration for reception of the uplink reference signal for the handover procedure is received via a radio resource control message.

FIG.11is a diagram illustrating an example process1100performed, for example, by a control node, in accordance with various aspects of the present disclosure. Example process1100is an example where the control node (e.g., an IAB donor405, an IAB node410, a serving node710, a control node720, a base station110, and/or the like) performs operations associated with uplink-centric handover in a wireless multi-hop network.

As shown inFIG.11, in some aspects, process1100may include transmitting, to a child node in the wireless multi-hop network, a transmission configuration for transmission of an uplink reference signal for a handover procedure (block1110). For example, the control node (e.g., using controller/processor240, memory242, transmit processor220, TX MIMO processor230, MOD232, antenna234, communication unit294, controller/processor290, memory292, and/or the like) may transmit, to a child node in the wireless multi-hop network, a transmission configuration for transmission of an uplink reference signal for a handover procedure, as described above.

As further shown inFIG.11, in some aspects, process1100may include transmitting, to a neighbor node in the wireless multi-hop network, a reception configuration for reception of the uplink reference signal for the handover procedure (block1120). For example, the control node (e.g., using controller/processor240, memory242, transmit processor220, TX MIMO processor230, MOD232, antenna234, communication unit294, controller/processor290, memory292, and/or the like) may transmit, to a neighbor node in the wireless multi-hop network, a reception configuration for reception of the uplink reference signal for the handover procedure, as described above.

As further shown inFIG.11, in some aspects, process1100may include receiving a measurement report based at least in part on the uplink reference signal for the handover procedure (block1130). For example, the control node (e.g., using antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, memory242, communication unit294, controller/processor290, memory292, and/or the like) may receive a measurement report based at least in part on the uplink reference signal for the handover procedure, as described above.

As further shown inFIG.11, in some aspects, process1100may include initiating the handover procedure based at least in part on receiving the measurement report (block1140). For example, the control node (e.g., using controller/processor240, memory242, transmit processor220, TX MIMO processor230, MOD232, antenna234, communication unit294, controller/processor290, memory292, and/or the like) may initiate the handover procedure based at least in part on receiving the measurement report, as described above.

In a first aspect, the transmission configuration indicates at least one of a resource for transmission of the uplink reference signal, a transmit power for transmission of the uplink reference signal, a beam configuration for transmission of the uplink reference signal, or a combination thereof.

In a second aspect, alone or in combination with the first aspect, the transmit power is determined based at least in part on a location of the neighbor node.

In a third aspect, alone or in combination with one or more of the first and second aspects, the reception configuration indicates at least one of a power saving mode configuration for the neighbor node, a resource for monitoring for the uplink reference signal, a beam configuration for monitoring for the uplink reference signal, or a combination thereof.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, process1100includes transmitting, to the neighbor node, a measurement and reporting configuration that indicates a condition for transmitting the measurement report.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the measurement report is received from the neighbor node based at least in part on the measurement and reporting configuration.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, initiating the handover procedure comprises at least one of transmitting a handover command to the child node via a parent node of the child node, transmitting a handover request to the parent node, transmitting a handover request to the neighbor node, or a combination thereof.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process1100includes transmitting, to the neighbor node, an instruction to modify a transmission mode of the neighbor node for transmission of a downlink reference signal by the neighbor node based at least in part on receiving the measurement report.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, process1100includes transmitting, to the neighbor node, a condition for modifying a transmission mode of the neighbor node for transmission of a downlink reference signal by the neighbor node.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, process1100includes determining at least one of the transmission configuration or the reception configuration to align a transmission time of the uplink reference signal with an active time period of the neighbor node.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, process1100includes determining at least one of the transmission configuration or the reception configuration to align a transmit beam direction for the uplink reference signal with a receive beam direction used by the neighbor node to monitor for the uplink reference signal.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the control node is a parent node of the child node, another node in the wireless multi-hop network, or a central unit in the wireless multi-hop network.