The present disclosure relates to apparatus, a method, and a computer program, and in particular, but not exclusively to apparatus, methods and computer programs related to configuring user equipment for lower layer inter-cell mobility.
Some communication systems use a cellular radio access network in which base station functionality for a cell is split between at least a distributed unit and a central unit.
According to a lower layer inter-cell mobility procedure, a decision to switch a user equipment from one cell to another may be made by a distributed unit operating the serving cell for the user equipment.
A method, comprising: generating an information set for a user equipment; wherein the information set at least includes information for configuring the user equipment for performing measurements for a mobility decision at a first distributed unit operating a first, serving cell of a radio access network; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network.
The information set may further comprise information for configuring the user equipment for reporting results of the measurements via the first cell, for making the mobility decision at the first distributed unit.
The information set may further comprise information for configuring the user equipment for operation in the second cell in the event of a decision at the first distributed unit to command the user equipment to perform serving cell change to the second cell.
Generating the information set may be based at least partly on information received via signalling associated with the user equipment.
Generating the information set may be based at least partly on information received via signalling not associated with the user equipment.
Generating the information set may be performed at the first distributed unit; and the method may comprise: receiving at the first distributed unit at least second cell measurement resource information regarding measurement resources for the second cell; and sending the generated information set to a central unit associated with the first distributed unit, for forwarding by the central unit to the user equipment.
Operation of the second cell may comprise making at least two types of reference signal transmissions, and the method may comprise: receiving at the first distributed unit an indicator of the type of reference signal transmission for the measurement resources for the second cell.
Generating the information set may be performed at a central unit associated with the first distributed unit; and the method may comprise: receiving at the central unit at least: second cell measurement resource information regarding measurement resources for the second cell; first cell measurement resource information regarding measurement resources for the first cell; and measurement reporting information about reporting measurement results to the first distributed unit via the first cell; and sending the generated information set to the user equipment.
Operation of the first cell may comprise making at least two types of reference signal transmissions, and the method may comprise: receiving at the central unit an indicator of the type of reference signal transmission for the measurement resources for the first cell; and sending to the second distributed unit a request for information about measurement resources for the same type of reference signal transmission in the second cell.
The method may further comprise: receiving at the central unit: information about measurement resources for the same type of reference signal transmission in the second cell, in the event that operation of the second cell comprises making the same type of reference signal transmission; or information about measurement resources for another type of reference signal transmission in the second cell, in the event that operation of the second cell does not comprise making the same type of reference signal transmission; and sending to the first distributed unit an indication of the type of reference signal transmission for which information about measurement resources was received from the second distributed unit.
Generating the information set may be performed at the second distributed unit; and the method may comprise: receiving at the second distributed unit at least: first cell measurement resource information regarding measurement resources for the first cell; and measurement reporting information about reporting measurement results to the first distributed unit via the first cell; and sending the generated information set to a central unit associated with the first distributed unit, for forwarding by the central unit to the user equipment.
The method may further comprise: sending, to the central unit for forwarding to the first distributed unit, at least one of the second cell measurement resource information regarding measurement resources for the second cell and information regarding transmission configuration indicator states for the second cell.
Operation of the first cell may comprise making at least two types of reference signal transmissions, and the method may comprise: receiving at the second distributed unit an indicator of the type of reference signal transmission for the measurement resources for the first cell; and including in the information set information about measurement resources for the same type of reference signal transmission in the second cell, in the event that operation of the second cell comprises making the same type of reference signal transmission; or including in the information set information about measurement resources for another type of reference signal in the second cell, in the event that operation of the second cell does not comprise making the same type of reference signal transmission.
A method, comprising: receiving an information set via a first, serving cell operated by a first distributed unit of a radio access network; wherein the information set at least includes information about performing measurements for a mobility decision at the first distributed unit; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network; performing measurements for at least the first and second cells according to the information set; reporting results of the measurements to the first distributed unit via the serving cell, for the mobility decision at the first distributed unit.
A method, comprising: sending to a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A method comprising: receiving at a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A method, comprising: receiving measurement resource information regarding measurement resources for at least one cell, wherein the measurement resource information identifies measurement resources mappable to a user equipment according to at least one parameter of the user equipment.
The at least one parameter may comprise capability of the user equipment.
Apparatus, comprising: means for generating an information set for a user equipment; wherein the information set at least includes information for configuring the user equipment for performing measurements for a mobility decision at a first distributed unit operating a first, serving cell of a radio access network; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network.
The information set may further comprise information for configuring the user equipment for reporting results of the measurements via the first cell, for making the mobility decision at the first distributed unit.
The information set may further comprise information for configuring the user equipment for operation in the second cell in the event of a decision at the first distributed unit to command the user equipment to perform serving cell change to the second cell.
The means for generating may comprise means for generating the information set based at least partly on information received via signalling associated with the user equipment.
The means for generating may comprise means for generating the information set based at least partly on information received via signalling not associated with the user equipment.
The apparatus may be the first distributed unit; and the apparatus may comprise: means for receiving at least second cell measurement resource information regarding measurement resources for the second cell; and means for sending the generated information set to a central unit associated with the first distributed unit, for forwarding by the central unit to the user equipment.
Operation of the second cell may comprise making at least two types of reference signal transmissions, and the apparatus may comprise: means for receiving an indicator of the type of reference signal transmission for the measurement resources for the second cell.
The apparatus may be a central unit associated with the first distributed unit; and the apparatus may comprise: means for receiving at least: second cell measurement resource information regarding measurement resources for the second cell; first cell measurement resource information regarding measurement resources for the first cell; and measurement reporting information about reporting measurement results to the first distributed unit via the first cell; and means for sending the generated information set to the user equipment.
Operation of the first cell may comprise making at least two types of reference signal transmission, and the apparatus may comprise: means for receiving an indicator of the type of reference signal transmission for the measurement resources for the first cell; and means for sending to the second distributed unit a request for information about measurement resources for the same type of reference signal transmission in the second cell.
The apparatus may further comprise: means for receiving: information about measurement resources for the same type of reference signal transmission in the second cell, in the event that operation of the second cell comprises making the same type of reference signal transmission; or information about measurement resources for another type of reference signal transmission in the second cell, in the event that operation of the second cell does not comprise making the same type of reference signal transmission; and means for sending to the first distributed unit an indication of the type of reference signal transmission for which information about measurement resources was received from the second distributed unit.
The apparatus may be the second distributed unit; and the apparatus may comprise: means for receiving at least: first cell measurement resource information regarding measurement resources for the first cell; and measurement reporting information about reporting measurement results to the first distributed unit via the first cell; and means for sending the generated information set to a central unit associated with the first distributed unit, for forwarding by the central unit to the user equipment.
The apparatus may further comprise: means for sending, to the central unit for forwarding to the first distributed unit, at least one of the second cell measurement resource information regarding measurement resources for the second cell and information regarding transmission configuration indicator states for the second cell.
Operation of the first cell may comprise making at least two types of reference signal transmissions, and the apparatus may comprise: means for receiving an indicator of the type of reference signal transmission for the measurement resources for the first cell; and means for: including in the information set information about measurement resources for the same type of reference signal transmission in the second cell, in the event that operation of the second cell comprises making the same type of reference signal transmission; or including in the information set information about measurement resources for another type of reference signal in the second cell, in the event that operation of the second cell does not comprise making the same type of reference signal transmission.
Apparatus, comprising: means for receiving an information set via a first, serving cell operated by a first distributed unit of a radio access network; wherein the information set at least includes information about performing measurements for a mobility decision at the first distributed unit; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network; means for performing measurements for at least the first and second cells according to the information set; means for reporting results of the measurements to the first distributed unit via the serving cell, for the mobility decision at the first distributed unit.
Apparatus, comprising: means for sending to a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
Apparatus comprising: means for receiving at a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
Apparatus, comprising: means for receiving measurement resource information regarding measurement resources for at least one cell, wherein the measurement resource information identifies measurement resources mappable to a user equipment according to at least one parameter of the user equipment.
The at least one parameter may comprise capability of the user equipment.
Apparatus comprising: at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus to perform: generating an information set for a user equipment; wherein the information set at least includes information for configuring the user equipment for performing measurements for a mobility decision at a first distributed unit operating a first, serving cell of a radio access network; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network.
The information set may further comprise information for configuring the user equipment for reporting results of the measurements via the first cell, for making the mobility decision at the first distributed unit.
The information set may further comprise information for configuring the user equipment for operation in the second cell in the event of a decision at the first distributed unit to command the user equipment to perform serving cell change to the second cell.
Generating the information set may be based at least partly on information received via signalling associated with the user equipment.
Generating the information set may be based at least partly on information received via signalling not associated with the user equipment.
The apparatus may be the first distributed unit; and the at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus to: receive at least second cell measurement resource information regarding measurement resources for the second cell; and send the generated information set to a central unit associated with the first distributed unit, for forwarding by the central unit to the user equipment.
Operation of the second cell may comprise making at least two types of reference signal transmissions, and the at least one memory and computer program code are configured to, with the at least one processor, cause the apparatus to: receive an indicator of the type of reference signal transmission for the measurement resources for the second cell.
The apparatus may be a central unit associated with the first distributed unit; and the at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus to: receive at least: second cell measurement resource information regarding measurement resources for the second cell; first cell measurement resource information regarding measurement resources for the first cell; and measurement reporting information about reporting measurement results to the first distributed unit via the first cell; and send the generated information set to the user equipment.
Operation of the first cell may comprise making at least two types of reference signal transmissions, and the at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus to: receive an indicator of the type of reference signal transmission for the measurement resources for the first cell; and send to the second distributed unit a request for information about measurement resources for the same type of reference signal transmission in the second cell.
The at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus to: receive: information about measurement resources for the same type of reference signal transmission in the second cell, in the event that operation of the second cell comprises making the same type of reference signal transmission; or information about measurement resources for another type of reference signal transmission in the second cell, in the event that operation of the second cell does not comprise making the same type of reference signal transmission; and send to the first distributed unit an indication of the type of reference signal transmission for which information about measurement resources was received from the second distributed unit.
The apparatus may be the second distributed unit; and the at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus to: receive at least: first cell measurement resource information regarding measurement resources for the first cell; and measurement reporting information about reporting measurement results to the first distributed unit via the first cell; and send the generated information set to a central unit associated with the first distributed unit, for forwarding by the central unit to the user equipment.
The at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus to: send, to the central unit for forwarding to the first distributed unit, at least one of the second cell measurement resource information regarding measurement resources for the second cell and information regarding transmission configuration indicator states for the second cell.
Operation of the first cell may comprise making at least two types of reference signal transmissions, and the at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus to: receive an indicator of the type of reference signal transmission for the measurement resources for the first cell; and include in the information set information about measurement resources for the same type of reference signal transmission in the second cell, in the event that operation of the second cell comprises making the same type of reference signal transmission; or include in the information set information about measurement resources for another type of reference signal in the second cell, in the event that operation of the second cell does not comprise making the same type of reference signal transmission.
Apparatus comprising: at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus to perform: receiving an information set via a first, serving cell operated by a first distributed unit of a radio access network; wherein the information set at least includes information about performing measurements for a mobility decision at the first distributed unit; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network; performing measurements for at least the first and second cells according to the information set; and reporting results of the measurements to the first distributed unit via the serving cell, for the mobility decision at the first distributed unit.
Apparatus comprising: at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus to perform: sending to a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
Apparatus comprising: at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus to perform: receiving at a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
Apparatus comprising: at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus to perform: receiving measurement resource information regarding measurement resources for at least one cell, wherein the measurement resource information identifies measurement resources mappable to a user equipment according to at least one parameter of the user equipment.
The at least one parameter may comprise capability of the user equipment.
Apparatus, comprising: generating circuitry for generating an information set for a user equipment; wherein the information set at least includes information for configuring the user equipment for performing measurements for a mobility decision at a first distributed unit operating a first, serving cell of a radio access network; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network.
Apparatus, comprising: receiving circuitry for receiving an information set via a first, serving cell operated by a first distributed unit of a radio access network; wherein the information set at least includes information about performing measurements for a mobility decision at the first distributed unit; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network; performing circuitry for performing measurements for at least the first and second cells according to the information set; reporting circuitry for reporting results of the measurements to the first distributed unit via the serving cell, for the mobility decision at the first distributed unit.
Apparatus, comprising: sending circuitry for sending to a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
Apparatus comprising: receiving circuitry for receiving at a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
Apparatus, comprising: receiving circuitry for receiving measurement resource information regarding measurement resources for at least one cell, wherein the measurement resource information identifies measurement resources mappable to a user equipment according to at least one parameter of the user equipment.
A computer readable medium comprising program instructions stored thereon for performing: generating an information set for a user equipment; wherein the information set at least includes information for configuring the user equipment for performing measurements for a mobility decision at a first distributed unit operating a first, serving cell of a radio access network; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network.
A computer readable medium comprising program instructions stored thereon for performing: receiving an information set via a first, serving cell operated by a first distributed unit of a radio access network; wherein the information set at least includes information about performing measurements for a mobility decision at the first distributed unit; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network; performing measurements for at least the first and second cells according to the information set; reporting results of the measurements to the first distributed unit via the serving cell, for the mobility decision at the first distributed unit.
A computer readable medium comprising program instructions stored thereon for performing: sending to a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A computer readable medium comprising program instructions stored thereon for performing: receiving at a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A computer readable medium comprising program instructions stored thereon for performing: receiving measurement resource information regarding measurement resources for at least one cell, wherein the measurement resource information identifies measurement resources mappable to a user equipment according to at least one parameter of the user equipment.
A non-transitory computer readable medium comprising program instructions stored thereon for performing: generating an information set for a user equipment; wherein the information set at least includes information for configuring the user equipment for performing measurements for a mobility decision at a first distributed unit operating a first, serving cell of a radio access network; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network.
A non-transitory computer readable medium comprising program instructions stored thereon for performing: receiving an information set via a first, serving cell operated by a first distributed unit of a radio access network; wherein the information set at least includes information about performing measurements for a mobility decision at the first distributed unit; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network; performing measurements for at least the first and second cells according to the information set; reporting results of the measurements to the first distributed unit via the serving cell, for the mobility decision at the first distributed unit.
A non-transitory computer readable medium comprising program instructions stored thereon for performing: sending to a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A non-transitory computer readable medium comprising program instructions stored thereon for performing: receiving at a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A non-transitory computer readable medium comprising program instructions stored thereon for performing: receiving measurement resource information regarding measurement resources for at least one cell, wherein the measurement resource information identifies measurement resources mappable to a user equipment according to at least one parameter of the user equipment.
A computer program comprising computer executable code which when run on at least one processor is configured to cause an apparatus at least to: generate an information set for a user equipment; wherein the information set at least includes information for configuring the user equipment for performing measurements for a mobility decision at a first distributed unit operating a first, serving cell of a radio access network; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network.
A computer program comprising computer executable code which when run on at least one processor is configured to cause an apparatus at least to: receive an information set via a first, serving cell operated by a first distributed unit of a radio access network; wherein the information set at least includes information about performing measurements for a mobility decision at the first distributed unit; wherein the measurements comprise at least: measurements for the first, serving cell, and measurements for a second cell operated by a second distributed unit of the radio access network; perform measurements for at least the first and second cells according to the information set; report results of the measurements to the first distributed unit via the serving cell, for the mobility decision at the first distributed unit.
A computer program comprising computer executable code which when run on at least one processor is configured to cause an apparatus at least to: send to a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A computer program comprising computer executable code which when run on at least one processor is configured to cause an apparatus at least to: receive at a unit of a radio access network an indicator indicating a type of reference signal transmission for which the unit of the radio access network is to provide information about resources for measurements for a mobility decision at a distributed unit of the radio access network.
A computer program comprising computer executable code which when run on at least one processor is configured to cause an apparatus at least to: receive measurement resource information regarding measurement resources for at least one cell, wherein the measurement resource information identifies measurement resources mappable to a user equipment according to at least one parameter of the user equipment.
In the above, many different aspects have been described. It should be appreciated that further aspects may be provided by the combination of any two or more of the aspects described above.
Various other aspects are also described in the following detailed description and in the attached claims.
Some example embodiments will now be described in further detail, by way of example only, with reference to the following examples and accompanying drawings, in which:
By way of example, the following description focusses on the example of user equipment (UE) and a radio access network (RAN) operating according to 3GPP 5G technology, but the underlying technique is also applicable to user equipment and radio access networks operating according to other technologies, such as more evolved 3GPP technology.
Embodiments of the invention are not, however, restricted to the system given as an example in
The functionality of a NG-RAN gNB (5G base station) is split into a central unit (gNB-CU), a plurality of distributed units (gNB-DU) associated with the gNB-CU, and one or more radio units (gNB-RU) associated with each gNB-DU. A gNB-RU provides the digital front end (DFE), parts of the PHY layer functionality, and digital beamforming functionality. A gNB-DU provides Layer 1/2 (L1/2) functionality, including MAC (Medium Access Control) functionality, RLC (Radio Link Control) functionality, and part of the PHY layer functionality. A gNB-CU provides higher layer functionality including Layer 3 (L3) functionality—RRC (Radio Resource Control) functionality and PDCP (Packet Data Convergence Protocol) functionality.
Each gNB-CU is connected to a core network user plane function (UPF), for routing and forwarding user data packets and for providing connectivity of devices to one or more external packet data networks (DN), and to an access mobility management function (AMF) for controlling access and mobility of user equipments.
The term “user equipment” (UE) here refers to any device, apparatus or component implementing at least 3GPP user equipment (UE) functionality.
The UE may be a mobile or static device (e.g. a portable or non-portable computing device) including, but not limited to, the following types of devices: mobile phone, smartphone, personal digital assistant (PDA), handset, device using a wireless modem (alarm or measurement device, etc.), laptop and/or touch screen computer, tablet, game console, notebook, and multimedia device. It should be appreciated that a UE device may also be a nearly exclusive uplink only device, of which an example is a camera or video camera loading images or video clips to a network. A UE device may also be a device having capability to operate in Internet of Things (IoT) network which is a scenario in which objects are provided with the ability to transfer data over a network without requiring human-to-human or human-to-computer interaction, e.g. to be used in smart power grids and connected vehicles. The device may also utilise cloud. In some applications, a UE device may comprise a user portable device with radio parts (such as a watch, earphones or eyeglasses) and the computation is carried out in the cloud. 5G enables using multiple input—multiple output (MIMO) antennas, and may involve large numbers of base stations (gNBs) including macro sites operating in co-operation with smaller stations and employing a variety of radio technologies depending on service needs, use cases and/or spectrum available. 5G mobile communications supports a wide range of use cases and related applications including video streaming, augmented reality, different ways of data sharing and various forms of machine type applications (such as (massive) machine-type communications (mMTC), including vehicular safety, different sensors and real-time control). 5G may employ multiple radio interfaces, e.g. below 6 GHz or above 24 GHz, cmWave and mmWave, and may also be integrable with existing legacy radio access technologies, such as LTE. Integration with LTE may be implemented, as a system, where macro coverage is provided by LTE and 5G radio interface access comes from small cells by aggregation to the LTE. In other words, 5G may support both inter-RAT operability (such as LTE-5G) and inter-RI operability (inter-radio interface operability, such as below 6 GHz—cmWave, 6 or above 24 GHz—cmWave and mmWave). 5G networks may employ network slicing, in which multiple independent and dedicated virtual sub-networks (network instances) may be created within the same infrastructure to run services that have different requirements on latency, reliability, throughput and mobility.
Low latency applications and services may be facilitated by bringing content close to the 5G system, which leads to local break out and multi-access edge computing (MEC). 5G enables analytics and knowledge generation to occur at the source of the data. This approach may involve leveraging resources that may not be continuously connected to a network such as laptops, smartphones, tablets and sensors. MEC provides a distributed computing environment for application and service hosting. It also has the ability to store and process content in close proximity to cellular subscribers for faster response time. Edge computing covers a wide range of technologies such as wireless sensor networks, mobile data acquisition, mobile signature analysis, cooperative distributed peer-to-peer ad hoc networking and processing also classifiable as local cloud/fog computing and grid/mesh computing, dew computing, mobile edge computing, cloudlet, distributed data storage and retrieval, autonomic self-healing networks, remote cloud services, augmented and virtual reality, data caching, Internet of Things (massive connectivity and/or latency critical), critical communications (autonomous vehicles, traffic safety, real-time analytics, time-critical control, healthcare applications).
5G may also utilize satellite communication to enhance or complement the coverage of 5G service, for example by providing backhauling. Possible use cases are providing service continuity for machine-to-machine (M2M) or Internet of Things (IoT) devices or for passengers on board of vehicles, Mobile Broadband, (MBB) or ensuring service availability for critical communications, and future railway/maritime/aeronautical communications. Satellite communication may utilise geostationary earth orbit (GEO) satellite systems, but also low earth orbit (LEO) satellite systems, in particular mega-constellations (systems in which hundreds of (nano)satellites are deployed). Each satellite in the mega-constellation may cover several satellite-enabled network entities that create on-ground cells. The on-ground cells may be created through an on-ground relay node or by a gNB located on-ground or in a satellite.
For simplicity of explanation, the examples described below are examples in which a single cell is identified as a target cell for L1/2 intercell mobility. However, there may be more than one target cell. For example, a plurality of target cells may comprise cells operated by a plurality of distributed units. For example, there may be one or more target cells operated by one or more DUs other than the DU operating the serving cell, and there may additionally be one or more target cells operated by the DU operating the serving cell.
UE is served by a serving cell operated by gNB-DU1. UE transmits a L3 measurement report via the serving cell (OPERATION 1 of
In the example shown in
According to another example, non-serving DU2 provides the L1/2 intercell mobility information to CU1 as part of non-UE associated signaling (i.e. before CU1 receives the L3 measurement report for UE). For example, non-serving DU2 may include the L1/2 intercell mobility information in a message (such as e.g. a F1 Setup Request message of the kind described at 3GPP TS 38.473, section 8.2.3.2, or a gNB-DU Configuration Update message of the kind described at TS 38.473, section 8.2.4.2) during the setup of the F1 interface between CU1 and DU2, or as part of a DU configuration update procedure for DU2. One or more common sets of L1/2 mobility information (e.g. CSI resource configuration(s) and TCI states) may be applicable for UEs configured with L1/L2 mobility. A plurality of sets may be mapped to respective levels of UE capability. CU1 may choose one of the sets for a specific UE based on information at CU1 about the capability of the specific UE.
According to one example, operations 6 to 8 of
According to another example, operations 6 and 8 of
In order to reduce the complexity of making both serving cell and target cell measurements at the UE and reporting the measurements to DU1, DU1 may decide on the measurement resources for the serving cell and the measurement reporting configuration based on information about the target cell resources for making L1/L2 mobility measurements in the target cell operated by DU2. DU1 may align/re-order the resources for making L1/2 mobility measurements in the serving cell and/or resources for reporting L1/2 mobility measurements via the serving cell depending on the information received from CU1 about target cell resources for making measurements in the target cell. For example, DU1 may align measurement type and align measurement resources with the aim of reducing battery consumption at UE. For example, serving DU1 may schedule L1/2 mobility measurement resources in the same time windows/frequency resources as those for the target cell operated by DU2.
DU1 generates a message (e.g. CSI Configuration Response message) including the requested information (OPERATION 2 of
According to one example variant of
According to one example variant of
The operations described above may be conditional on UE having provided to the NG-RAN a UE capability indicator indicating capability for L1/L2 inter-cell mobility.
In the example shown in
According to another example, DU2 may provide L1/2 mobility information to CU1 using an F1 interface procedure used in the event that no target cell is prepared.
According to another example, non-serving DU2 provides the L1/2 mobility information to CU1 as part of non-UE associated signaling (i.e. before CU1 receives the L3 measurement report for UE). For example, non-serving DU2 may include the L1/2 mobility information in a message (such as e.g. a F1 Setup Request message of the kind described at 3GPP TS 38.473, section 8.2.3.2, or a gNB-DU Configuration Update message of the kind described at TS 38.473, section 8.2.4.2) during the setup of the F1 interface (between CU1 and DU2) or as part of a DU configuration update procedure for DU2. One or more common sets of L1/2 mobility information may be applicable for UEs capable of L1/L2 mobility. A plurality of common sets of L1/2 mobility information may be mapped to respective levels of UE capability. CU1 may choose one of the common sets of L1/2 mobility for a UE according to the capability of the UE.
UE sends a L3 measurement report to CU1 via serving cell and DU1 (OPERATIONS 1 and 2 of
In the example shown in
According to another example, serving DU1 provides the L1/L2 mobility information to CU1 as part of non-UE associated signaling (i.e. before CU1 receives the L3 measurement report for UE). For example, serving DU1 may include the L1/L2 mobility information in a message (such as e.g. a F1 Setup Request message of the kind described at 3GPP TS 38.473, section 8.2.3.2, or a gNB-DU Configuration Update message of the kind described at TS 38.473, section 8.2.4.2) during the setup of F1 interface between CU1 and DU1, or as part of a DU configuration update procedure for DU1. One or more common sets of L1/2 mobility information may be applicable for UEs configured with L1/L2 mobility. A plurality of common sets of L1/2 mobility information may be mapped to respective levels of UE capability. CU1 may choose one of the common sets of L1/2 mobility information according to information at CU1 about the capability of the UE.
In all of the example embodiments described above; a combination of UE-associated signalling and non-UE associated signalling may be used. Depending on one or more conditions, CU1 may decide (for a specific target cell for a specific UE) to use L1/2 mobility information etc. already received via non-UE associated signalling, or CU1 may decide to instead use UE-associated signalling. For example, if the load of the serving DU1 is high, CU1 may decide to use UE-associated signalling for L1/2 inter-cell mobility related configuration and preparation.
In the example embodiments described above, DU1 and DU2 are associated with the same CU (CU1). However, the same kind of techniques are also applicable when the target cell is operated by a DU associated with another CU (e.g. DU3 associated with CU2 in
In the example embodiments describe above, a TCI state for a cell defines the Quasi Co-Location (QCL) information for receiving the PDCCH (Physical Downlink Control Channel) or PDSCH (Physical Downlink Shared Channel) signal of the cell. TCI state indicates to a UE the RS (reference signal) index (SSB index or CSI-RS index) based on which the channel information(s) (doppler shift, doppler spread, average delay, delay spread, spatial RX parameter) apply for receiving PDCCH or PDSCH of the cell. The configuration of TC states is described, for example, at TS 3GPP 38.331.
Regarding all of the examples of
In the event that one RS type (e.g. CSI-RS) is selected, and e.g. DU2 cannot provide L1/2 mobility information for the selected RS-type (e.g. because normal operation of the target cell operated by DU2 does not involve the selected RS-type), the fallback position may be that DU2 instead includes L1/2 mobility information for the RS type (e.g. SSB) that is part of the normal operation of the target cell. In such an event, UE is configured to also make and report mobility measurements for at least one RS type (e.g. SSB) common to the operation of both serving and target cells, in order to optimise a comparison of the serving and target cells at DU1 for deciding on cell change.
The above-described techniques facilitate L1/L2 handover between cells operated by different gNB-DUs. The above-described techniques facilitate the initiation at a serving cell DU of the transmission of a MAC CE or L1 message for switching the UE from one TCI state to another TCI state for another cell operated by another gNB-DU.
The above-described techniques facilitate a decision at the serving cell DU about whether to change the UE from the serving cell to a target cell.
The above-described co-ordination of L1/L2 mobility information for one cell with the L1/L2 mobility information for another cell can better avoid a risk of an inaccurate L1/L2 mobility decision at the serving gNB-DU.
It is to be noted that example embodiments may be implemented as circuitry, in software, hardware, application logic or a combination of software, hardware and application logic. In an example embodiment, the application logic, software or an instruction set is maintained on any computer-readable media. In the context of this document, a “computer-readable medium” may be any media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as the base stations or user equipment of the above-described example embodiments.
As used in this application, the term “circuitry” refers to all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and (b) to combinations of circuits and software (and/or firmware), such as (as applicable): (i) to a combination of processor(s) or (ii) to portions of processor(s)/software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as the user equipment or base stations of the above-described embodiments, to perform various functions) and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present. This definition of ‘circuitry’ applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term “circuitry” would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware. The term “circuitry” would also cover, for example and if applicable to the particular claim element, a baseband integrated circuit or applications processor integrated circuit for a mobile phone or a similar integrated circuit in server, a cellular network device, or other network device.
The features, advantages, and characteristics described herein can be combined in any suitable manner in one or more example embodiments. One skilled in the relevant art will recognize that such example embodiments can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages can be recognized in certain embodiments that may not be present in all example embodiments. One having ordinary skill in the art will readily understand that the example embodiments as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although some embodiments have been described based upon these example embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of example embodiments.
Number | Date | Country | Kind |
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202241000753 | Jan 2022 | IN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2022/086642 | 12/19/2022 | WO |