Minimization of drive tests for multicast / broadcast services in new radios

Abstract

According to one aspect, an apparatus for a terminal device is provided. The apparatus is configured to perform the following operations. The apparatus receives, from an access node, a Minimization of Drive Tests (MDT) measurement configuration for one or more Multicast Broadcast Services (MBSs). Further, the apparatus performs MDT measurements on broadcast transmissions associated with the one or more cells for the one or more MBSs based on the received MDT measurement configuration. Finally, the apparatus sends to the access node an MDT report formed based on the received MDT measurement configuration. The MDT report includes at least information about a result of the MDT measurement. Results of the MDT measurements are indexed in an MDT report based on the one or more cell identifiers of the one or more cells.

Description

Technical Field

[0001] Various embodiments relate to wireless communications. Background Art

[0002] Minimization of Drive Tests (MDT) is a standardized mechanism implemented in many current wireless communication systems (e.g., 5G communication systems). MDT enables network operators to utilize terminal devices within the network to perform radio measurements and obtain associated location information in order to evaluate network performance. The use of MDT helps to reduce the need for traditional drive tests. For example, an MDT mechanism has been defined for multicast broadcast single frequency network (MBSFN) long term evolution (LTE) deployments. However, due to the differences between LTE and NR, the MDT mechanism for MBSFN LTE is not suitable for use in new radio deployments using MBSFN. Summary of the invention

[0003] According to one aspect, a device for a terminal device of a wireless communication network is provided, the device comprising:

[0004] at least one processor; and

[0005] at least one memory including computer program code;

[0006] The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least perform:

[0007] receiving, from an access node of a wireless communication network, a minimization of drive tests (MDT) measurement configuration for one or more multicast broadcast services (MBS);

[0008] performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs based on the received MDT measurement configuration; and

[0009] An MDT report formed based on the received MDT measurement configuration is sent to the access node or another access node of the wireless communication network, wherein the MDT report includes at least information about the result of the MDT measurement of the broadcast transmission for one or more MBSs, and wherein the result of the MDT measurement is indexed in the MDT report based on one or more cell identifiers of one or more cells.

[0010] According to one aspect, there is provided an apparatus for an access node of a wireless communication network, the apparatus comprising:

[0011] at least one processor; and

[0012] at least one memory including computer program code;

[0013] The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least perform:

[0014] An MDT measurement configuration for one or more MBSs is sent to a terminal device of a wireless communication network, wherein the MDT measurement configuration defines a configuration for the following operations of the terminal device: performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs, and forming an MDT report for sending to the access node or another access node of the wireless communication network, the MDT report including at least information about the results of the MDT measurements on the broadcast transmissions for the one or more MBSs, and indexing the results of the MDT measurements in the MDT report based on one or more cell identifiers of the one or more cells.

[0015] According to one aspect, there is provided a method comprising:

[0016] Receiving, by a terminal device of the wireless communication network, an MDT measurement configuration for one or more MBSs from an access node of the wireless communication network;

[0017] performing, by the terminal device, MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs based on the received MDT measurement configuration; and

[0018] An MDT report formed based on the received MDT measurement configuration is sent by the terminal device to the access node or another access node of the wireless communication network, wherein the MDT report includes at least information about the results of the MDT measurement of the broadcast transmission for one or more MBSs, and wherein the results of the MDT measurement are indexed in the MDT report based on one or more cell identifiers of one or more cells.

[0019] According to one aspect, there is provided a method comprising:

[0020] An MDT measurement configuration for one or more MBSs is sent by an access node of a wireless communication network to a terminal device of the wireless communication network, wherein the MDT measurement configuration defines a configuration for the following operations of the terminal device: performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs, and forming an MDT report for sending to the access node of the wireless communication network, the MDT report including at least information about the results of the MDT measurements on the broadcast transmissions for the one or more MBSs, and indexing the results of the MDT measurements in the MDT report based on one or more cell identifiers of the one or more cells.

[0021] According to one aspect, a computer program is provided, the computer program comprising instructions for causing an apparatus as a terminal device in a wireless communication network to at least perform the following operations:

[0022] receiving, from an access node of a wireless communication network, an MDT measurement configuration for one or more MBSs;

[0023] performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs based on the received MDT measurement configuration; and

[0024] An MDT report formed based on the received MDT measurement configuration is sent to the access node or another access node of the wireless communication network, wherein the MDT report includes at least information about the result of the MDT measurement of the broadcast transmission for one or more MBSs, and wherein the result of the MDT measurement is indexed in the MDT report based on one or more cell identifiers of one or more cells.

[0025] According to one aspect, a computer program is provided, the computer program comprising instructions for causing an apparatus as an access node of a wireless communication network to at least perform the following operations:

[0026] An MDT measurement configuration for one or more MBSs is sent to a terminal device of a wireless communication network, wherein the MDT measurement configuration defines a configuration for the following operations of the terminal device: performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs, and forming an MDT report for sending to an access node of the wireless communication network, the MDT report including at least information about the results of the MDT measurements on the broadcast transmissions for the one or more MBSs, and indexing the results of the MDT measurements in the MDT report based on one or more cell identifiers of the one or more cells.

[0027] According to an aspect, the subject matter of the independent claims is provided. Embodiments are defined in the dependent claims.

[0028] One or more implementation examples are set forth in greater detail in the drawings and the following description. Other features will be apparent from the detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Embodiments will be described in more detail below with reference to the accompanying drawings, in which:

[0030] Figure 1 illustrates an exemplary wireless communication system;

[0031] Figure 2A , Figure 2B , Figure 3 and Figure 4 illustrates an exemplary process according to an embodiment; and

[0032] Figure 5 and Figure 6 An apparatus according to an embodiment is illustrated. DETAILED DESCRIPTION

[0033] The following embodiments are presented as examples only. Although this specification may refer to "one", "an" or "some" embodiments and / or examples at several locations in the text, this does not necessarily mean that each reference is to the same embodiment and / or example, nor does it mean that a particular feature applies only to a single embodiment and / or example. Individual features of different embodiments and / or examples may also be combined to provide other embodiments and / or examples.

[0034] In the following, different exemplary embodiments are described by using a radio access architecture based on Advanced Long Term Evolution (Advanced LTE, LTE-A) or New Radio (NR, 5G) as an example of an access architecture to which the embodiments can be applied, but the embodiments are not limited to such architectures. It is obvious to a person skilled in the art that the embodiments can also be applied to other kinds of communication networks with suitable components by appropriately adjusting the parameters and procedures. Some examples of other options for suitable systems are Universal Mobile Telecommunications System (UMTS) Radio Access Network (UTRAN or E-UTRAN), Long Term Evolution (LTE, same as E-UTRA), Wireless Local Area Network (WLAN or WiFi), Worldwide Interoperability for Microwave Access (WiMAX), Personal Communications Service (PCS), Wideband Code Division Multiple Access (WCDMA), systems using Ultra-Wideband (UWB) technology, sensor networks, Mobile Ad Hoc Networks (MANETs), and Internet Protocol Multimedia Subsystem (IMS), or any combination thereof.

[0035] Figure 1 An example of a simplified system architecture is depicted showing some elements and functional entities, which are all logical units, the implementation of which may differ from what is shown. Figure 1 The connections shown in are logical connections; the actual physical connections may be different. It is obvious to those skilled in the art that the system typically includes in addition to Figure 1 Other functions and structures than those shown in .

[0036] However, the embodiments are not limited to the systems given as examples, but a person skilled in the art may apply the solution to other communication systems having the necessary characteristics.

[0037] Figure 1The example of FIG. 1 shows a portion of an exemplary radio access network.

[0038] Figure 1 User equipment 100 and 102 are shown to be configured to be wirelessly connected to an access node (such as (e / g) NodeB) 104 providing the cell on one or more communication channels in the cell. The physical link from the user equipment to the (e / g) NodeB is called an uplink or reverse link, and the physical link from the (e / g) NodeB to the user equipment is called a downlink or forward link. It should be understood that the (e / g) NodeB or its functions can be implemented by using any node, host, server or access point suitable for such use.

[0039] The communication system usually includes more than one (e / g)NodeB, in which case, the (e / g)NodeB can also be configured to communicate with each other through wired or wireless links designed for this purpose. These links can be used for signaling purposes. (e / g)NodeB is a computing device configured to control the radio resources of the communication system to which it is coupled. NodeB can also be referred to as a base station, an access point, or any other type of interface device including a relay station capable of operating in a wireless environment. (e / g)NodeB includes or is coupled to a transceiver. A connection to an antenna unit is provided from the transceiver of the (e / g)NodeB, and the antenna unit establishes a bidirectional radio link to a user equipment. The antenna unit may include multiple antennas or antenna elements. (e / g)NodeB is also connected to a core network 110 (CN or next generation core NGC). Depending on the system, the corresponding part on the CN side may be a service gateway (S-GW, routing and forwarding user data packets), a packet data network gateway (P-GW) for providing a connection between a user equipment (UE) and an external packet data network, or a mobile management entity (MME), etc.

[0040] In some cases, the (e / g)NodeB may be divided into two or more physical entities, including a centralized unit (CU) 108 and at least one distributed unit (DU) 104. The CU may provide support for higher layers of the protocol stack, such as Service Data Adaptation Protocol (SDAP), Packet Data Convergence Protocol (PDCP), and Radio Resource Control (RRC), while the DU may provide support for lower layers of the protocol stack, such as Radio Link Control (RLC), Medium Access Control (MAC), and the physical layer.

[0041] User equipment (also referred to as UE, user device, user terminal, terminal device, etc.) illustrates a type of device for which resources on the air interface are allocated and specified, and therefore any features of the user equipment described herein can be implemented with corresponding devices (such as relay nodes). An example of such a relay node is a layer 3 relay (self-backhaul relay) towards a base station.

[0042] User equipment generally refers to a portable computing device including a wireless mobile communication device operating with or without a subscriber identification module (SIM), including but not limited to the following types of devices: mobile stations (mobile phones), smart phones, personal digital assistants (PDAs), mobile phones, devices using wireless modems (alarms or measuring devices, etc.), laptops and / or touch screen computers, tablet computers, game consoles, notebook computers, and multimedia devices. It should be understood that user equipment can also be a nearly exclusive uplink-only device, an example of which is a camera or video camera that loads images or video clips to a network. User equipment can also be a device with the ability to operate in an Internet of Things (IoT) network, which is a scenario in which an object can be provided with the ability to transmit data over a network without human-to-human or human-to-computer interaction. User equipment (or in some embodiments, a layer 3 relay node) is configured to perform one or more user equipment functions. User equipment can also be referred to as a subscriber unit, mobile station, remote terminal, access terminal, user terminal, or user equipment (UE), just to mention a few names or devices.

[0043] The various techniques described herein can also be applied to cyber-physical systems (CPS) (systems of cooperating computing elements that control physical entities). CPS can implement and utilize a large number of interconnected ICT devices (sensors, actuators, processors, microcontrollers, etc.) embedded in physical objects at different locations. Mobile cyber-physical systems (where the physical system in question has inherent mobility) are a subcategory of cyber-physical systems. Examples of mobile physical systems include mobile robots and electronic devices transported by humans or animals.

[0044] It should be understood that Figure 1 In the figures, for the sake of clarity only, the user equipment is depicted as comprising 2 antennas. The number of receiving and / or transmitting antennas may naturally vary depending on the current implementation.

[0045] Furthermore, although the apparatus is described as a single entity, different units, processors and / or memory units may be implemented. Figure 1 Not all are shown).

[0046] 5G enables the use of multiple-input multiple-output (MIMO) antennas, more base stations or nodes than LTE (the so-called small cell concept), including macro sites that operate in collaboration with smaller stations and adopt a variety of radio technologies (depending on service requirements, use cases and / or available spectrum). 5G mobile communications support a wide range of use cases and related applications, including video streaming, augmented reality, different data sharing methods and various forms of machine-type applications (including vehicle safety), different sensors and real-time control. It is expected that 5G will have multiple radio interfaces (i.e., below 6GHz, centimeter wave (cmWave) and millimeter wave (mmWave)), and will also be able to integrate with existing traditional radio access technologies (such as LTE). At least in the early stages, integration with LTE can be implemented as a system in which macro coverage is provided by LTE and 5G radio interface access comes from small cells through aggregation to LTE. In other words, 5G plans to support both inter-RAT operability (such as LTE-5G) and inter-RI operability (inter-radio interface operability, such as below 6GHz-cmWave, below 6GHz-cmWave-mmWave). One of the concepts being considered for use in 5G networks is network slicing, where multiple independent and dedicated virtual subnetworks (network instances) can be created within the same infrastructure to run services with different requirements for latency, reliability, throughput, and mobility.

[0047] The current architecture in LTE networks is completely distributed in the radio and completely centralized in the core network. Low-latency applications and services in 5G require content to be close to the radio, leading to local grooming and multi-access edge computing (MEC). 5G enables analysis and knowledge generation to be performed at the data source. This approach requires the use of resources that may not be continuously connected to the network, such as laptops, smartphones, tablets, and sensors. MEC provides a distributed computing environment for application and service hosting. It is also able to store and process content in locations close to cellular users to achieve faster response times. Edge computing covers a wide range of technologies such as wireless sensor networks, mobile data acquisition, mobile signature analysis, collaborative distributed peer-to-peer self-organizing networking and processing (also classified as local cloud / fog computing and grid / mesh computing, dew computing, mobile edge computing, cloudlet, distributed data storage and retrieval), autonomous self-healing networks, remote cloud services, augmented reality and virtual reality, data caching, Internet of Things (large-scale connectivity and / or latency critical), critical communications (autonomous driving vehicles, traffic safety, real-time analysis, time-critical control, healthcare applications).

[0048] The communication system may also be capable of communicating with, or using services provided by, other networks 112, such as a public switched telephone network or the Internet. The communication network may also be capable of supporting the use of cloud services, for example, at least a portion of the core network operations may be provided as a cloud service (this is in the context of Figure 1 The communication system may also include a central control entity or the like, providing facilities for networks of different operators to collaborate, for example, in spectrum sharing.

[0049] Edge cloud can be introduced into the radio access network (RAN) by utilizing network function virtualization (NVF) and software defined networking (SDN). Using edge cloud can mean that access node operations are at least partially performed in a server, host or node that is operably coupled to a remote radio head (RRH) or base station including the radio part. Node operations can also be distributed among multiple servers, nodes or hosts. The application of cloudRAN architecture enables RAN real-time functions to be performed on the RAN side (in the distributed unit DU 104) and non-real-time functions to be performed in a centralized manner (in the centralized unit CU 108).

[0050] It should also be understood that the division of labor between core network operations and base station operations may be different from that of LTE or even non-existent. Some other technological advances that may be used are big data and all-IP, which may change the way networks are built and managed. 5G (or New Radio NR) networks are designed to support multiple hierarchical structures, where MEC servers can be placed between the core and the base station or NodeB (gNB). It should be understood that MEC can also be applied in 4G networks.

[0051] 5G can also leverage satellite communications to enhance or supplement the coverage of 5G services, for example by providing backhaul. Possible use cases are to provide service continuity for machine-to-machine (M2M) or Internet of Things (IoT) devices or passengers on board, or to ensure service availability for critical communications and future rail / maritime / aeronautical communications. Satellite communications can leverage geostationary orbit (GEO) satellite systems, as well as low Earth orbit (LEO) satellite systems, in particular mega-constellations (systems in which hundreds of (nano) satellites are deployed). Each satellite 106 in a mega-constellation can cover several satellite-enabled network entities that create ground cells. Ground cells can be created by ground relay nodes 104 or by gNBs located on the ground or in satellites.

[0052] It is obvious to a person skilled in the art that the depicted system is only an example of a part of a radio access system, and the system may actually include multiple (e / g)NodeBs, user equipment may access multiple radio cells, and the system may also include other devices, such as physical layer relay nodes or other network elements. At least one of the (e / g)NodeBs may be a home (e / g)NodeB. In addition, in a geographical area of ​​the radio communication system, a plurality of different kinds of radio cells as well as a plurality of radio cells may be provided. A radio cell is a macro cell (or umbrella cell), which is typically a large cell with a diameter of up to tens of kilometers, or a smaller cell such as a micro cell, a femto cell or a pico cell. Figure 1 The (e / g)NodeB can provide any kind of these cells. A cellular radio system can be implemented as a multi-layer network including several cells. Generally speaking, in a multi-layer network, one access node provides one or more cells of one type, and therefore multiple (e / g)NodeBs are required to provide this network structure.

[0053] In order to meet the need to improve the deployment and performance of communication systems, the concept of "plug and play" (e / g) NodeB has been introduced. Generally speaking, in addition to the home (e / g) NodeB (H(e / g)nodeB), a network that can use "plug and play" (e / g) NodeB also includes a home NodeB gateway, or HNB-GW ( Figure 1 (not shown in the figure). An HNB gateway (HNB-GW) (which is usually installed in the operator's network) can aggregate services from a large number of HNBs back to the core network.

[0054] 6G networks are expected to adopt flexible decentralized and / or distributed computing systems and architectures and ubiquitous computing, with local spectrum licensing, spectrum sharing, infrastructure sharing, and intelligent automated management, based on mobile edge computing, artificial intelligence, short packet communications, and blockchain technology. The main features of 6G will include intelligent connection management and control functions, programmability, integrated sensing and communication, reduced energy footprint, trusted infrastructure, scalability, and affordability. In addition to this, 6G also targets new use cases, which cover the integration of positioning and sensing functions into system definitions to unify user experience in the physical and digital worlds.

[0055] Figure 1The system may be a (5G NR or 6G) communication system configured to support multicast broadcast service (MBS). The MBS mechanism used in the system may be based on single cell point-to-multipoint (SC-PTM) transmission. In SC-PTM, MBS transmission is performed cell-specifically. In such a system, any terminal device 100, 102 operating in radio resource control (RRC) connection mode may be able to receive messages sent using a first MBS delivery mode (or MBS delivery mode 1) corresponding to multicast, and all terminal devices 100, 102 operating in any RRC operation mode may be able to receive messages sent using a second MBS delivery mode (or MBS delivery mode 2) corresponding to broadcast. MBS delivery mode 1 may provide transport blocks (TBs) to terminal devices 100, 102 in both point-to-multipoint (PTM) and point-to-point (PTP) modes. Such a system may lack hybrid automatic repeat request (HARQ) or any other feedback mechanism for broadcast transmission (although such a feedback mechanism may be available for multicast transmission). A fixed modulation and coding scheme (MCS) may be used for broadcast transmissions without dynamic link adaptation. However, for broadcast transmissions, (blind) retransmissions or repetitions may be possible.

[0056] Figure 1 The (5G NR or 6G) system can use the multicast traffic channel (MTCH) and the multicast control channel (MCCH) as logical channels to provide broadcast transmissions. The MCCH provides control information to decode the broadcast data sent using the MTCH. The same transport and physical channels as unicast (i.e., downlink shared channel DL-SCH and physical data shared channel PDSCH) can also be used for broadcast transmissions. The transport block containing the MCCH can be sent via the PDSCH by scrambling its cyclic redundancy check (CRC) using a separate MCCH radio network temporary identifier (MCCH-RNTI). Similarly, the MTCH can be sent via the PDSCH using the group RNTI (G-RNTI).

[0057] Figure 1 The system may support a Minimization of Drive Tests (MDT) framework (or specifically, an NR MDT framework). Minimization of Drive Tests (MDT) is a framework or mechanism for enabling network operators to perform radio measurements using terminal devices within the network and obtain associated location-based information in order to evaluate network performance. The use of MDT helps to reduce the need for traditional drive tests. Such traditional drive tests typically use a motor vehicle containing mobile radio network air interface measurement equipment to measure and evaluate various parameters related to the coverage, capacity and quality of service (QoS) of the mobile radio network.

[0058] The NR MDT framework is based on a trace and control plane based architecture. MDT originates from the orchestration and management (OAM) layer where the MDT configuration (i.e., trace activation) is initiated. After network management, measurements are configured to the terminal device via RRC signaling. The MDT report from the terminal device 100, 102 to the access node 104 can be forwarded to the trace collection entity of the core network 110.

[0059] Can be targeted Figure 1 The (5G NR or 6G) system defines three different MDT data collection modes.

[0060] The first MDT data collection mode ("Immediate MDT mode") may be used by terminal devices operating in RRC connected mode. The first MDT data collection mode may be applicable to NR and EN-DC (Evolved Universal Terrestrial Radio Access - New Radio). The term EN-DC refers to E-UTRA NR dual connectivity. In the first MDT data collection mode, radio measurements are performed (i.e., data is collected) and reported back to the access node in real time (i.e., without delay).

[0061] The second MDT data collection mode ("logged MDT mode") can be used by terminal devices operating in RRC idle mode or RRC inactive mode. In the second MDT data collection mode, radio measurements are performed (i.e., data is collected), but reporting does not occur in real time (i.e., there may be a significant delay between the radio measurements and the reporting of the radio measurements). Specifically, the terminal device may begin collecting data (i.e., performing radio measurements) when transitioning to RRC idle or inactive mode, and report the availability of MDT data (i.e., the results of the radio measurements) when returning to RRC connected mode (e.g., using the UEInformation process). In order to enable reporting of the availability of MDT data, an availability bit may be included in the RRCSetupComplete, RRCResumeComplete, RRCReconfigurationComplete and / or RRCReestablishment-Complete messages. Subsequently, a (NR) MDT report (e.g., including serving / neighboring cell radio measurements, location information, timestamps, and / or event / failure records) may be sent by the terminal device to the access node. The second MDT data collection mode may be configured to the terminal device using a dedicated (RRC) measurement configuration message (ie, RRC LoggedMeasurementConfiguration message). The trigger for reporting the results of the radio measurements may be a periodic trigger or an event-based trigger (eg, an A2-like event or an out-of-coverage event). The A2 event corresponds to an event triggered when the sum of the signal quality of the serving cell (eg, RSRP or RSRQ) and a predefined hysteresis parameter is below a predefined threshold.

[0062] The third MDT data collection mode ("deferred reporting mode") is triggered by a predefined event (eg, detection of a radio link failure or detection of a connection establishment failure).

[0063] In some embodiments, Figure 1 The system defines at least a second MDT data collection mode.

[0064] While MDT reporting for Multimedia Broadcast Multicast Service (MBMS) has been defined for LTE MBSFN deployments, no such definition exists for NR deployments. In the case of NR, in addition to the changes resulting from the network technology itself (NR compared to LTE), there are significant changes in the multicast / broadcast architecture.

[0065] One of the main differences between NR MBS and LTE MBMS is the use of DL-SCH and PDSCH instead of dedicated channels as used by LTE MBMS. In addition, MBSFN is transparent to the terminal device. Therefore, the terminal device has no information about any MBSFN area.

[0066] For at least the reasons stated above, MDT reports from LTE MBMS cannot be used to optimize the network in NR. Therefore, a solution is needed that enables the network to successfully perform optimizations for broadcast transmissions using MDT reports designed specifically for the needs of the 5G NR MBS framework.

[0067] Figure 2A and Figure 2B A process for performing MDT measurements and reporting thereof according to an embodiment is illustrated. Figure 2A The process may be performed by a terminal device or a part of a terminal device. The terminal device is Figure 1 Any one of the terminal devices 100, 102 in. Figure 2B The process may be performed by an access node or a part of an access node. The access node may be Figure 1 The access node 104 in. Hereinafter, for the sake of brevity, the entity that performs these processes is referred to as a device.

[0068] refer to Figure 2A , the apparatus initially receives an MDT measurement configuration for one or more MBSs from an access node of a wireless communication network (e.g., a 5G NR wireless communication network) in box 201. The wireless communication network may be the same wireless communication network to which the terminal device is connected. The apparatus may configure itself based on an MDT measurement configuration message. The MDT measurement configuration defines a configuration for the terminal device to perform, in whole or in part, the operations to be described in detail in conjunction with boxes 202, 203. That is, the MDT measurement configuration may at least define a configuration for the terminal device to perform the following operations: perform MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs (box 202) and form an MDT report for sending to the access node or another access node of the wireless communication network (box 203). The MDT measurement configuration may be included in an MDT measurement configuration message, which may be an RRC message.

[0069] The MDT measurement configuration may define a trigger for reporting the results of the MDT measurements. The trigger may be a periodic trigger or an event-based trigger (eg, an A2-like event or an out-of-coverage event).

[0070] The MDT measurement configuration may define one or more first (average) parameters for performing an averaging when (blind) repetitions of a plurality of different broadcast transmissions are received by a terminal device (e.g. in combination with Figure 3 described in detail).

[0071] Additionally or alternatively, the MDT measurement configuration may include one or more second (average) parameters used to determine the average MCS index.

[0072] The apparatus performs or causes to be performed MDT measurements for one or more MBSs in box 202 based on the received MDT measurement configuration and based on a broadcast transmission (of a transport block) associated with one or more cells of the wireless communication network. In other words, the broadcast transmission may be received from one or more access nodes that respectively serve one or more cells of the wireless communication network. Thus, the apparatus performs or causes to be performed MDT measurements when accessing one or more cells. In general, one or more MDT measurements may be performed per visited cell. It may be assumed that the terminal device (being or including the apparatus) operates in RRC idle, inactive or connected operating mode and / or using MBS delivery mode 1 and / or 2 during the MDT measurement in box 202.

[0073] The MDT measurements are performed on a per-cell basis (ie, individually for each cell). In other words, each of the MDT measurements may be associated with or mapped to a specific (camped) cell identifier identifying the cell associated with the given MDT measurement.

[0074] In some embodiments, the apparatus may specifically perform or cause to be performed measurements of reference signal received power (RSRP) and / or reference signal received quality (RSRQ) based on a broadcast transmission in block 202. Here, the broadcast transmission may correspond to or include one or more reference signals of a predefined type. The predefined type of the one or more reference signals may be, for example, a synchronization signal block (SSB) or a tracking reference signal (TRS).

[0075] In particular, TRS can be useful in the context of transparent MBSFN for terminal devices. SSBs are cell-specific transmissions, and therefore it is generally undesirable that they are synchronized between neighboring cells. However, TRS is highly configurable. Therefore, the same TRS resources (time-frequency resources) can be configured from cells in an MBSFN area so that the terminal device will indeed measure the sum of the signals transmitted synchronously by the cells of a specific MBSFN area.

[0076] In some embodiments, the MDT measurements performed in block 202 may additionally or alternatively include various measurements related to decoding of at least one transport block included in a broadcast transmission, such as in conjunction with Figure 3 described in further detail.

[0077] In some embodiments, the one or more cells may include a plurality of cells. In other words, the apparatus (or terminal device) may receive broadcast transmissions from a plurality of cells over time, for example due to mobility.

[0078] In addition to being performed on a per-cell basis, when MTCH is employed, the MDT measurements in box 202 may be performed on a per-G-RNTI basis (i.e., individually for each G-RNTI) and / or when MCCH is employed, the MDT measurements in box 202 may be performed on a per-MCCH-RNTI basis (i.e., individually for each MCCH-RNTI) in order to distinguish between different services and control / data planes. Here, it may be assumed that the terminal device (or the apparatus) is configured with one or more G-RNTIs (or multiple G-RNTIs) and / or is configured with one or more MCCH-RNTIs (or multiple MCCH-RNTIs). As described above, a transport block containing an MCCH may be sent by an access node via a PDSCH by scrambling its cyclic redundancy check (CRC) using the MCCH-RNTI (of the terminal device), while a transport block containing an MTCH may be sent by an access node via a PDSCH using a CRC scrambled using the G-RNTI. The apparatus (or terminal device) may perform descrambling or decoding of received broadcast transmissions using one or more G-RNTIs and / or one or more MCCH-RNTIs configured to the terminal device. The apparatus may record (i.e., store in a database) the results of MTCH measurements for each G-RNTI configured to the terminal device and / or the results of MCCH measurements for each MCCH-RNTI configured to the terminal device.

[0079] Thus, the MDT measurements as defined in block 202 may include:

[0080] one or more MDT measurements of broadcast transmissions associated with one or more MTCHs for one or more MBSs, wherein the one or more MTCHs are respectively associated with one or more G-RNTIs configured for the terminal device (and used for reception of the broadcast transmissions); and / or

[0081] One or more MDT measurements of broadcast transmissions for one or more MBSs associated with one or more MCCHs, wherein the one or more MCCHs are respectively associated with one or more MCCH-RNTIs configured to the terminal device (and used for reception of the broadcast transmissions).

[0082] In other words, each MDT measurement may be associated with a specific G-RNTI or a specific MCCH-RNTI. In these cases, each of the MDT measurements may also be associated with a specific cell in which the relevant measurement is performed.

[0083] In some embodiments, when the terminal device is operating in MBS delivery mode 1 and / or MBS delivery mode 2 (as defined above), MDT measurements may be performed on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs in block 202. In other words, all MDT measurements may have been performed when operating in MBS delivery mode 1 or MBS delivery mode 2, or some MDT measurements may have been performed when operating in MBS delivery mode 1 and other MDT measurements may be performed when operating in MBS delivery mode 2.

[0084] In some embodiments, the device may store the results of the MDT measurements (and other information associated with one or more MDT measurements, such as one or more cell identifiers, one or more G-RNTIs, one or more MCCH-RNTIs, one or more MBS delivery modes, and / or one or more MCS indexes for decoding) in a database. The results of the MDT measurements may be indexed (or sorted or organized) in the database based on one or more cell identifiers, one or more G-RNTIs, one or more MCCH-RNTIs, MBS delivery modes, and / or one or more MCS indexes for decoding. The database may be an internal or external database of the device, or an internal or external database of the terminal device. This process may also be referred to as logging. The logged information may be stored for at least a predefined amount of time (e.g., 48 hours) after logging.

[0085] The device sends or causes an MDT report (for one or more MBSs) to an access node of the wireless communication network in block 203. The access node may or may not be an access node from which the MDT measurement configuration is received and / or an access node participating in one or more MDT measurements. The MDT report is formed by the device at least in part based on the MDT measurement configuration. Here, the MDT report includes at least information about the results (or at least some of them) of the MDT measurement. The results of the MDT measurement are indexed (or sorted or organized) in the MDT report based at least on one or more cell identifiers of one or more cells. The one or more cell identifiers of the one or more cells may be included in the MDT report. In some cases (for example, when the one or more cell identifiers consist of a single cell identifier), one or more cell identifiers may be omitted from the MDT report. In other words, each (or at least one) result of the MDT measurement may be associated with one of the one or more cell identifiers in the MDT report or be marked to one of the one or more cell identifiers in the MDT report so that it is possible to distinguish which MDT measurement result is related to which cell based on the MDT report. The results of the MDT measurement may correspond to measured values ​​of RSRP, RSRQ and / or BLER, for example. The one or more cell identifiers may be, for example, a cell global identifier (CGI).

[0086] In some embodiments, the MDT report includes information about a predefined type (e.g., SSB or TRS) of a reference signal associated with the measurement of RSRP and / or RSRQ. The results of the measurement of RSRP and / or RSRQ may be indexed (or sorted or organized) in the MDT report based on the predefined type of the reference signal (if multiple different types are used).

[0087] If the MDT measurements (or at least some of them) are performed on a per-G-RNTI basis, as described in conjunction with block 202, the results of one or more MDT measurements of broadcast transmissions associated with one or more MTCHs for one or more MBSs may be indexed (or ordered or organized) in an MDT report based on one or more G-RNTIs associated with the one or more MTCHs (and based on one or more cell identifiers). In this case, the MDT report may include at least information about the results of the one or more MDT measurements, the one or more cell identifiers, and the one or more G-RNTIs. In other words, each MDT measurement result (e.g., RSRP and / or RSRQ value) or at least one MDT measurement result may be associated with or tagged to a specific cell identifier and a specific G-RNTI in the MDT report.

[0088] If the MDT measurements (or at least some of them) are performed on a per MCCH-RNTI basis, as described in conjunction with block 202, the results of one or more MDT measurements of broadcast transmissions associated with one or more MCCHs for one or more MBSs may be indexed (or ordered or organized) in an MDT report based on one or more MCCH-RNTIs associated with the one or more MCCHs (and based on one or more cells). In this case, the MDT report may include at least information about the results of the MDT measurements, one or more cell identifiers, and one or more MCCH-RNTIs. In other words, each MDT measurement result (e.g., RSRP and / or RSRQ value) or at least one MDT measurement result may be associated with or tagged to a specific cell identifier and a specific MCCH-RNTI in the MDT report.

[0089] In some embodiments, the results of MDT measurements for broadcast transmissions of one or more MBSs may be indexed (or sorted or organized) in an MDT report based on at least one MBS delivery mode used to perform the MDT measurements. Information about the MBS delivery mode used may be included in the MDT report (tagged to the results of the MDT measurements).

[0090] In some embodiments where the MDT measurement in block 202 is a radio measurement of a reference signal of a predefined type (eg, SSB or TRS), the MDT report sent in block 203 may also include information about the predefined type.

[0091] In some embodiments, the MDT report may include one or more MDT measured DL-SCH block error rates (BLERs).

[0092] In some embodiments, the MDT report may include information about at least one carrier frequency used in one or more MDT measurements (ie, used in broadcast transmissions).

[0093] In some embodiments, the MDT report may include location information (ie, location information of the terminal device at the time of the MDT measurement), a timestamp associated with the MDT measurement, and / or one or more event or failure records.

[0094] refer to Figure 2B, the apparatus (i.e., an access node or a portion thereof) sends an MDT measurement configuration for one or more MBSs to a terminal device of the wireless communication network in block 211. The MDT measurement configuration defines a configuration for the terminal device to perform MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs and to form an MDT report for transmission to the access node or another access node of the wireless communication network. Here (and as combined with Figure 2A The MDT report includes at least information about the results of MDT measurements for broadcast transmissions of one or more MBSs. The results of the MDT measurements are indexed in the MDT report based at least on one or more cell identifiers of one or more cells. The one or more cell identifiers may be included in the MDT report. The MDT measurement configuration may be sent as an RRC message (i.e., an RRC LoggedMeasurementConfiguration message).

[0095] In general, the MDT measurement configuration sent in block 211 may be defined to achieve, for example, Figure 2A Any embodiment of the terminal device side discussed. For example, the MDT measurement configuration (or specifically, the configuration for performing MDT measurements defined therein for the terminal device) may define one or more of the following:

[0096] - one or more measurements of RSRP and / or RSRQ based on broadcast transmissions (e.g., SSB and / or TRF),

[0097] - one or more MDT measurements of broadcast transmissions for one or more MBSs associated with one or more MTCHs (the one or more MTCHs are respectively associated with one or more G-RNTIs configured to the terminal device),

[0098] - based on one or more G-RNTIs associated with the one or more MTCHs, indexing in an MDT report the results of one or more MDT measurements of broadcast transmissions associated with the one or more MTCHs for the one or more MBSs,

[0099] - one or more MDT measurements of broadcast transmissions for one or more MBSs associated with one or more MCCHs (the one or more MCCHs are respectively associated with one or more MCCH-RNTIs configured to the terminal device),

[0100] - indexing results of one or more MDT measurements of broadcast transmissions associated with one or more MCCHs for one or more MBSs in an MDT report based on one or more MCCH-RNTIs associated with the one or more MCCHs,

[0101] - based on the MBS delivery mode used for the MDT measurements, the results of the MDT measurements for the broadcast transmission of one or more MBSs are indexed in the MDT report,

[0102] - a determination of the block error rate to be performed after each reception of a broadcast transmission,

[0103] - determination of the number of repetitions and / or the average number of said repetitions required by a terminal device for decoding at least one transport block of a broadcast transmission for one or more MBSs,

[0104] - determination of the number of unnecessary repetitions of at least one transport block for broadcast transmission of one or more MBSs and / or the average number of said unnecessary repetitions, said unnecessary repetitions being reception repetitions not required by a terminal device for decoding said at least one transport block,

[0105] - one or more first averaging parameters for calculating an average number of repetitions required for a terminal device to decode at least one transport block of a broadcast transmission for one or more MBSs and / or an average number of unnecessary repetitions of at least one transport block of a broadcast transmission for one or more MBSs,

[0106] - determination of at least one modulation and coding scheme used in decoding a broadcast transmission for one or more MBSs,

[0107] - determination of an average modulation and coding scheme index used in decoding a broadcast transmission for one or more MBSs, and

[0108] - one or more second averaged parameters, the one or more second averaged parameters being used for calculating an average modulation and coding scheme index.

[0109] Figure 2B The following blocks 212, 213 may be considered optional (as indicated using dashed lines). That is, in some embodiments, one or both of the actions associated with blocks 212, 213 may be performed by an access node different from the access node that performs the sending of the MDT measurement configuration in block 211.

[0110] The apparatus broadcasts one or more signals (eg, including one or more SSBs and / or one or more TRSs) to be measured by the terminal device in block 212 .

[0111] The apparatus receives an MDT report from the terminal device in block 213. The MDT may (or may not) include results of MDT measurements performed based on the one or more signals sent in block 212. The MDT report may be, for example, combined with Figure 2A The block 203 is defined in detail.

[0112] After receiving the MDT report in block 213, the access node may transmit the MDT report or at least some of the MDT measurement results included therein to a core network entity (e.g., a trace collection entity) to enable optimization of broadcast transmission in the wireless communication network. Since the results of the MDT measurements are provided at least per cell, the parameters of the broadcast transmission in each cell visited by the terminal device may be optimized respectively.

[0113] NR broadcasts using MBS Delivery Mode 2 (DM-2) do not support Hybrid Automatic Repeat Request (HARQ) feedback. Therefore, (blind) repetitions can be used to improve the decoding performance of broadcasts in NR. However, the network has no way of knowing how many (blind) repetitions are required for the terminal device to successfully decode the TB.

[0114] For example, the network may have configured 4 (blind) retransmissions (AggregationLevel=4) so ​​that each TB (possibly with different redundancy versions) is sent 5 times to the terminal devices. However, it is possible that all terminal devices decode the TB in only 3 transmissions, and 2 out of 5 transmissions are usually redundant and will reduce the spectrum efficiency. If the network will know when this happens, it can optimize the number of repetitions in the long run based on the current channel conditions of the network. The network can also change the MCS if necessary.

[0115] Figure 3 Another process for performing MDT measurements involving repeated broadcast transmissions and reporting the MDT measurements to overcome the problem according to an embodiment is illustrated. The illustrated process may be performed by a terminal device or a portion of a terminal device. The terminal device may be Figure 1 Any one of the terminal devices 100, 102. In the following, for the sake of brevity, the entity that performs the process is referred to as an apparatus.

[0116] Combination Figure 2A Any characteristics and definitions provided may apply here.

[0117] refer to Figure 3 The apparatus initially receives an MDT measurement configuration in block 301 and then performs or causes to be performed MDT measurements based on broadcast transmissions received from one or more access nodes that respectively serve one or more cells of a wireless communication network (e.g., a 5G NR wireless communication network), similar to as described in conjunction with Figure 2AAs described in boxes 201 and 202.

[0118] Here, the execution of the MDT measurement corresponds to blocks 302 and 303. In this embodiment, it is assumed that the broadcast transmission sent by one or more access nodes to the terminal device (or apparatus) includes the original broadcast transmission and the (blind) repetition of the original broadcast transmission. Specifically, one or more (blind) repetitions may be sent for each (or at least one) of the original broadcast transmissions.

[0119] Thus, the apparatus receives in block 302 a plurality of broadcast transmissions comprising at least some of the original broadcast transmissions sent by the one or more access nodes and (blind) repetitions of the original broadcast transmissions. The plurality of broadcast transmissions may be defined herein as being combined with Figure 2A as discussed in box 202 (e.g., each of them may correspond to the transmission of an SSB or a TRS, and / or they may be associated with one or more cells, one or more G-RNTIs, one or more MCCH-RNTIs, and / or one or more MBS delivery modes used by the terminal device).

[0120] The device decodes at least one transport block (TB) based on the received broadcast transmission of the transport block in box 303. In other words, for each original broadcast transmission, decoding can be performed based on one or more broadcast transmissions including the original broadcast transmission (if available) and / or zero or more of one or more available (blind) repetitions of the original broadcast transmission. It should be noted that in some cases, the original broadcast transmission may not be successfully received, but one or more of its repetitions may be successfully received. The number of zero or more of the one or more available (blind) repetitions used in decoding can be selected as the minimum number that results in successful decoding. The minimum number of (blind) repetitions required for successful decoding may, for example, depend on the signal quality (which in turn depends on, for example, current channel conditions).

[0121] In some embodiments, the execution (performed by the apparatus) of the MDT measurement based on the received MDT measurement configuration (corresponding to Figure 2A Box 202 and Figure 3 Blocks 302, 303) may also include determining a block error rate (BLER) (or performing a measurement thereof) after each (or at least one) reception of a broadcast transmission. Here, receiving a broadcast transmission may include receiving an original (ie, initial) broadcast transmission and its repetitions.

[0122] In some embodiments, the execution (performed by the apparatus) of the MDT measurement based on the received MDT measurement configuration (corresponding to Figure 2A Box 202 and Figure 3Boxes 302, 303) may also include determining the number of repetitions required to decode the broadcast transmission for one or more MBSs and / or the average number of repetitions required to decode the broadcast transmission for one or more MBSs. In general, one or more values ​​(or at least one average value) for the number of repetitions may be determined based on the broadcast transmission for one or more MBSs. Additionally or alternatively, the execution of the MDT measurement may include determining the number of unnecessary repetitions of at least one transport block for the broadcast transmission for one or more MBSs (or performing its measurement) and / or the average number of unnecessary repetitions of at least one transport block for the broadcast transmission for one or more MBSs (or performing its measurement). Here, the unnecessary repetition may be a reception repetition that is not required for decoding the at least one transport block. Similarly, here, one or more values ​​(or at least one average value) for the number of unnecessary repetitions may be determined based on the broadcast transmission for one or more MBSs.

[0123] As described above, the averaging for calculating the average number of (blind) necessary or unnecessary repetitions may be performed according to one or more first (average) parameters defined in the MDT measurement configuration received from the access node.

[0124] In some embodiments, the execution (performed by the apparatus) of the MDT measurement based on the received MDT measurement configuration (corresponding to Figure 2A Box 202 and Figure 3 Blocks 302, 303 of the MDT measurement may also include determining at least one MCS used in decoding broadcast transmissions for one or more MBSs (or performing a measurement thereof). Additionally or alternatively, the performance of the MDT measurement may include determining an average MCS index used in decoding broadcast transmissions for one or more MBSs (or performing at least one measurement thereof).

[0125] As described above, the averaging used to determine the average MCS index may be performed based on one or more second (average) parameters defined in the MDT measurement configuration received from the access node.

[0126] The apparatus sends, or causes to be sent, an MDT report to an access node of the wireless communication network (which may or may not be an access node participating in MDT measurements) in block 304, similar to Figure 2A The MDT report includes at least information about results of a plurality of MDT measurements indexed based on one or more cell identifiers of one or more cells associated with the plurality of MDT measurements. In general, the MDT report may include any information described in conjunction with block 203 as being included in the MDT report.

[0127] Here, the MDT report also includes measurement result information related to decoding. That is, the MDT report may include:

[0128] information about the number or average number of (blind) repetitions required to decode the at least one transport block, and / or

[0129] Information about the number or average number of unnecessary (blind) repetitions of the broadcast transmission which were received but not required for decoding the at least one transport block.

[0130] In some embodiments, decoding related information may be provided in the MDT report per cell, per G-RNTI or MCCH-RNTI, per MCS (index) and / or per MBS delivery mode.

[0131] Additionally or alternatively, the MDT report may include measurement result information related to decoding, represented as a BLER measured after each broadcast transmission (i.e., after each reception of the original broadcast transmission and after each reception of its (blind) repetition). In some embodiments, this information may be provided in the MDT report per cell, per MCS (index), per G-RNTI or MCCH-RNTI, and / or per MBS delivery mode.

[0132] In some embodiments, the MDT report may also include measurement result information (e.g., including at least one MCS index) about at least one MCS used in decoding the at least one transport block of the broadcast transmission for one or more MBSs. Additionally or alternatively, the MDT report may also include information about an average MCS index of at least one MCS used in decoding the at least one transport block of the broadcast transmission for one or more MBSs.

[0133] The network can optimize the (blind) repetition number and / or MCS based on the MDT reports.

[0134] In some embodiments, the device may store (ie, record) any of the above decoding-related information in a database.

[0135] Figure 4 The figure shows the signaling between the access node and the terminal device for configuring MDT measurement, performing the configured MDT measurement, and reporting the result of the MDT measurement. The terminal device may be Figure 1 Any one of the terminal devices 100, 102, and the access node can be Figure 1 access node 104.

[0136] refer to Figure 4 , assuming that initially in block 401 the terminal device is operating in RRC connected mode. The terminal device may be connected at least exclusively to Figure 4 The access node shown in . Figure 4 The access node shown in may (initially) be a serving access node for a terminal device.

[0137] The access node sends an MDT measurement configuration message to the terminal device in message 402, which defines the configuration for MDT measurements (for one or more MBSs) and subsequent MDT reporting, as described in conjunction with box 201 of Figure 2. The MDT measurement configuration message may specifically define a logged MDT mode configuration, i.e., a configuration of a second MDT data collection mode ("logged MDT mode") that can be used by a terminal device operating in RRC idle mode or RRC inactive mode. Therefore, the configuration message may be an RRCLoggedMeasurementConfiguration message. The MDT measurement configuration message (or specifically, the RRCLoggedMeasurementConfiguration message) may originate from an MBS configuration from an operation and maintenance (OAM) center of the core network, wherein the logging is independent of the RRC operating mode.

[0138] Generally speaking, an MDT measurement configuration message (eg, a LoggedMeasurementConfiguration message) may include one or more of the following:

[0139] -Configuration of trigger logging events. This parameter specifies the period for storing MDT measurement results. It can be configured in seconds as a multiple of the applied RRC idle mode discontinuous reception (DRX), i.e., a multiple of 1.28s, which is a factor or multiple of the RRC idle mode DRX.

[0140] - Configuration of the logging duration. This configuration parameter defines a timer that is activated at the configuration moment. The timer may continue independently of, for example, an RRC operating mode change, a RAT change, or a registered public land mobile network (RPLMN) change. When the timer expires, logging may be stopped and the configuration may be cleared (except for parameters required for further reporting, e.g., network absolute timestamp, trace reference, trace logging session reference, and target cell identifier TCE ID).

[0141] - Network absolute timestamp, which will be used as a time reference for end devices.

[0142] - Tracking reference parameters as dictated by the OAM configuration.

[0143] - Trace logging session reference as dictated by the OAM configuration.

[0144] - TCE ID as indicated by the OAM configuration.

[0145] -MDT Public Land Mobile Network (PLMN) List, which indicates the PLMNs where measurement collection and log reporting are allowed. It is a subset of the Equivalent Public Land Mobile Network (EPLMN) list and the RPLMNs under the logged measurement configuration.

[0146] - Configuration of a logging area. As long as the terminal device is within a configured logging area (e.g. defined as a set of cells), it can log measurements. The scope of the logging area can consist of one of the following:

[0147] - A list of global cell identities (or identifiers) (eg, up to 32 global cell identifiers). If this list is configured, the terminal device will only log measurements when camped on any of these cells.

[0148] - A list of Tracking Areas (TA) or Location Areas (LA) or Routing Areas (RA) (e.g. up to 8 TAs, LAs or RAs). If this list is configured, the terminal device will only log measurements when camped in any cell belonging to the pre-configured TA / LA / RA.

[0149] - The configured logging area may span across the PLMNs in the MDT PLMN list. If no area is configured, the terminal device will log measurements of all PLMNs in the MDT PLMN list.

[0150] The terminal device receives the MDT measurement configuration message in block 403 , and also configures itself according to the MDT measurement configuration message in block 403 .

[0151] The terminal device switches from the RRC connected mode to the RRC inactive or idle mode in block 404. Figure 4 404. The handover may include communication between the terminal device and the access node (e.g., at least transmission of an RRC release message from the access node to the terminal device). Subsequently, when operating in RRC inactive or idle mode, the terminal device performs (and logs) MDT measurements in block 405 based on broadcast transmissions received from one or more access nodes serving one or more cells of the wireless communication network, respectively, according to the (log MDT) configuration defined via the configuration message. The one or more access nodes may or may not include Figure 4 One or more MDT measurements may be performed as described above in conjunction with block 202 of FIG. 2 and / or Figure 3 The process is performed as described in blocks 302 and 303 of .

[0152] The terminal device switches back to RRC connected mode in block 406. Figure 4It is not explicitly shown in the figure, but the switching in block 406 may include completing an RRC connection establishment procedure involving communication between the terminal device and the access node.

[0153] After switching back to the RRC connected mode in block 406, the terminal device sends a message including an indication that the access node records MDT data available (i.e., the results of the MDT measurements are available and therefore an MDT report can be sent upon request) to the access node in message 407. Message 407 may be an RRC setup complete message.

[0154] After receiving the message including the indication in block 408 , the access node sends an MDT information request (for requesting to send an MDT report) to the terminal device in a message 409 .

[0155] After receiving the MDT information request in block 410, the terminal device generates or forms an MDT report in block 411 according to the MDT measurement configuration defined via the configuration message 402 and based on the recorded measurement information, and then sends the MDT report to the access node in block 412. In other embodiments, the MDT report may have been generated before sending the message 407.

[0156] The access node receives the MDT report from the terminal device in block 413 .

[0157] Although in Figure 4 In the embodiment, it is assumed that the MDT measurements are performed when the terminal device is operating in RRC idle or inactive mode, but in other embodiments (also as described in conjunction with Figure 2), the MDT measurements (or at least some of them) may be performed by the terminal device when operating in RRC connected mode. In such embodiments, the MDT report may be generated and sent to the serving access node directly after the MDT measurements are performed (or periodically / periodically or upon request of the access node). In other words, in such embodiments, the reporting of the MDT measurement results may not necessarily be as detailed in the example above. Figure 4 In the embodiment of the present invention, the terminal device must first switch to RRC connected mode before any MDT reporting can be performed. This embodiment may correspond to Figure 4 A process in which (at least) blocks 404 and 406 are omitted.

[0158] Although Figure 4 The case where the access node that configures the terminal device (using message 402) is the same as the access node that is notified of the measurement results and requests and receives the MDT report (using elements 407 to 413) is illustrated, but in other embodiments, two different access nodes may perform the functions. One, both, or neither of the two access nodes may participate in the MDT measurements performed in block 405.

[0159] With the help of Figure 2A , Figure 2B , Figure 3 and Figure 4 There is no absolute time order for the described blocks, related functions, and information exchanges (messages), and some of them may be executed simultaneously or in an order different from the given order. Other functions may also be executed between or within them, and other information may be sent and / or other rules may apply. Some blocks or parts of blocks or one or more pieces of information may also be omitted or replaced with corresponding blocks or parts of blocks or one or more pieces of information.

[0160] Figure 5 An apparatus 501 according to some embodiments is illustrated. Specifically, Figure 5 The apparatus 501 may be illustrated as being for a terminal device (ie forming part of a terminal device) or as being or comprising a terminal device. In either case, the terminal device in question may be Figure 1 Any one of the terminal devices 100, 102.

[0161] The apparatus 501 may include one or more control circuits 520 (such as at least one processor) and at least one memory 530 including one or more algorithms 531 (such as computer program code (software)), wherein the at least one memory and the computer program code (software) are configured to enable the apparatus to perform any one of the exemplary functions of the above-mentioned apparatus (or terminal device) together with the at least one processor. The at least one memory 530 may also include at least one database 532.

[0162] refer to Figure 5 The one or more communication control circuits 520 of the device 501 include at least an MDT measurement and reporting circuit 521, which is configured to perform MDT measurements and report the results of the MDT measurements to the access node (in the form of an MDT report). To this end, the MDT measurement and reporting circuit 521 of the device 501 is configured to use one or more separate circuits to perform the above, for example, by means of Figure 2A and / or Figure 3 and / or Figure 4 At least some functions of the apparatus (or terminal device) described by elements 401, 403 to 407, 410 and / or 411.

[0163] refer to Figure 5 , the memory 530 may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory.

[0164] refer to Figure 5, the device 501 may also include different interfaces 510 such as one or more communication interfaces (TX / RX), which include hardware and / or software for implementing communication connections according to one or more communication protocols. Specifically, one or more communication interfaces 510 may include, for example, an interface that provides a connection to the core network of the Internet and a wireless communication network. One or more communication interfaces 510 may provide the device with communication capabilities to communicate in a cellular communication system and enable communication between other terminal devices and different network nodes or units / elements (e.g., access nodes). One or more communication interfaces 510 may include standard known components, such as amplifiers, filters, frequency converters, (de) modulators and encoder / decoder circuits, and one or more antennas controlled by corresponding control units.

[0165] Figure 6 An apparatus 601 according to some embodiments is illustrated. Specifically, Figure 6 The apparatus 601 for an access node may be illustrated (i.e., forming part of an access node) or may be an access node or include an access node. In either case, the access node in question may be Figure 1 access node 104.

[0166] The device 601 may include one or more control circuits 620 (such as at least one processor) and at least one memory 630 including one or more algorithms 631 (such as computer program code (software)), wherein the at least one memory and the computer program code (software) are configured to enable the device to perform any one of the exemplary functions of the above-mentioned device (or access node) together with the at least one processor. The at least one memory 630 may also include at least one database 632.

[0167] refer to Figure 6 The one or more communication control circuits 620 of the apparatus 601 at least include an MDT measurement configuration circuit 621, which is configured to perform MDT measurement configuration of the terminal device. To this end, the MDT measurement configuration circuit 621 of the apparatus 601 is configured to use one or more separate circuits to perform the above, for example, by means of Figure 2B and / or Figure 4 At least some functionality of the device (or access node) described by elements 408, 409, 413.

[0168] refer to Figure 6 , memory 630 may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory.

[0169] refer to Figure 6 , the device 601 may also include different interfaces 610 such as one or more communication interfaces (TX / RX), which include hardware and / or software for implementing communication connections according to one or more communication protocols. Specifically, one or more communication interfaces 610 may include, for example, an interface that provides a connection to the core network of the Internet and a wireless communication network. One or more communication interfaces 610 may provide the device with communication capabilities to communicate in a cellular communication system, and enable communication with terminal equipment and different network nodes or units / elements (e.g., other access nodes). One or more communication interfaces 610 may include standard known components, such as amplifiers, filters, frequency converters, (de) modulators and encoder / decoder circuits, and one or more antennas controlled by corresponding control units.

[0170] As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) a hardware circuit implementation only (such as an implementation in analog and / or digital circuits only), and (b) a combination of hardware circuits and software (and / or firmware), such as (as applicable): (i) a combination of analog and / or digital hardware circuits with software / firmware, and (ii) any portion of a hardware processor (including a digital signal processor) with software, software, and memory that work together to enable an apparatus (such as a terminal device or access node) to perform various functions; and (c) a hardware circuit and processor (such as a microprocessor or a portion of a microprocessor) that requires software (e.g., firmware) to operate, but the software may not be present when it is not required for operation. This definition of "circuitry" applies to all uses of the term in this application (including any claims). As a further example, as used in this application, the term "circuitry" also covers an implementation of a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its accompanying software and / or firmware. For example, and if applicable to a particular claim element, the term "circuitry" would also cover a baseband integrated circuit for use in an access node or terminal device or other computing or network equipment.

[0171] In an embodiment, in combination Figure 2A , Figure 2B , Figure 3 and Figure 4At least some of the processes described may be performed by an apparatus that includes corresponding components for performing at least some of the processes described. Some example components for performing these processes may include at least one of the following: a detector, a processor (including dual-core and multi-core processors), a digital signal processor, a controller, a receiver, a transmitter, an encoder, a decoder, a memory, RAM, ROM, software, firmware, a display, a user interface, a display circuit, a user interface circuit, user interface software, display software, a circuit, an antenna, an antenna circuit, and a circuit. In an embodiment, at least one processor, a memory, and a computer program code constitute a processing component or include a computer program code for performing the processing according to the present invention. Figure 2A , Figure 2B , Figure 3 and Figure 4 Any one embodiment or operation thereof may comprise one or more computer program code portions to perform one or more operations.

[0172] According to an embodiment, there is provided an apparatus (for a terminal device), the apparatus comprising means for performing the following operations:

[0173] receiving, from an access node of a wireless communication network, a minimization of drive tests (MDT) measurement configuration for one or more multicast broadcast services (MBS);

[0174] performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs based on the received MDT measurement configuration; and

[0175] An MDT report formed based on the received MDT measurement configuration is sent to the access node or another access node of the wireless communication network, wherein the MDT report includes at least information about the result of the MDT measurement of the broadcast transmission for one or more MBSs, and wherein the result of the MDT measurement is indexed in the MDT report based on one or more cell identifiers of one or more cells.

[0176] According to an embodiment, there is provided an apparatus (for an access node), the apparatus comprising means for performing the following operations:

[0177] An MDT measurement configuration for one or more MBSs is sent to a terminal device of a wireless communication network, wherein the MDT measurement configuration defines a configuration for the following operations of the terminal device: performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs, and forming an MDT report for sending to the access node or another access node of the wireless communication network, the MDT report including at least information about the results of the MDT measurements on the broadcast transmissions for the one or more MBSs, and indexing the results of the MDT measurements in the MDT report based on one or more cell identifiers of the one or more cells.

[0178] The embodiments as described may also be implemented in the form of a computer process defined by a computer program or part thereof. The combined process may be implemented by executing at least a part of a computer program including corresponding instructions. Figure 2A , Figure 2B , Figure 3 and Figure 4 Embodiments of the described methods. The computer program may be provided as a computer-readable medium including program instructions stored thereon, or may be provided as a non-transitory computer-readable medium including program instructions stored thereon. The computer program may be in source code form, object code form, or some intermediate form, and it may be stored in some carrier, which may be any entity or device capable of carrying the program. For example, the computer program may be stored on a computer program distribution medium readable by a computer or processor. The computer program medium may be, for example, but not limited to, a recording medium, a computer memory, a read-only memory, an electrical carrier signal, a telecommunication signal, and a software distribution package. The computer program medium may be a non-transitory medium. The coding of the software for executing the embodiments shown and described falls completely within the scope of those of ordinary skill in the art.

[0179] Although the embodiments have been described above with reference to the examples according to the accompanying drawings, it is clear that the embodiments are not limited thereto, but can be modified in various ways within the scope of the appended claims. Therefore, all words and expressions should be interpreted broadly, and they are intended to illustrate the embodiments rather than to limit them. It will be apparent to those skilled in the art that, with the advancement of technology, the inventive concept can be implemented in various ways. In addition, it is apparent to those skilled in the art that the described embodiments can (but not necessarily) be combined with other embodiments in various ways.

Claims

1. A device for a terminal device of a wireless communication network, the device comprising: at least one processor; as well as at least one memory including computer program code; The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least perform: receiving, from an access node of the wireless communication network, a minimization of drive tests (MDT) measurement configuration for one or more multicast broadcast services (MBS); performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs based on the received MDT measurement configuration; as well as and sending an MDT report formed based on the received MDT measurement configuration to the access node or another access node of the wireless communication network, wherein the MDT report includes at least information about results of MDT measurements of broadcast transmissions for the one or more MBSs, and wherein the results of the MDT measurements are indexed in the MDT report based on one or more cell identifiers of the one or more cells.

2. The device according to claim 1, wherein: The at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to perform the MDT measurement based on the received MDT measurement configuration by at least: Based on the broadcast transmission, a measurement of a reference signal received power RSRP and / or a reference signal received quality RSRQ is performed, wherein the broadcast transmission comprises one or more reference signals of a predefined type.

3. The device according to claim 2, wherein: The predefined type is a synchronization signal block or a tracking reference signal.

4. The device according to claim 2 or 3, wherein: The MDT report includes information of predefined types regarding one or more reference signals associated with the measurement of the RSRP and / or the RSRQ.

5. A device according to any one of the preceding claims, wherein: The MDT measurement for the broadcast transmission of the one or more MBSs includes: One or more MDT measurements of broadcast transmissions associated with one or more multicast traffic channels MTCH for one or more MBSs, wherein the one or more MTCHs are respectively associated with one or more group radio network temporary identifiers G-RNTI configured to the terminal device.

6. The device according to claim 5, wherein: Results of one or more MDT measurements of broadcast transmissions of one or more MBSs associated with the one or more MTCHs are indexed in the MDT report based on the one or more G-RNTIs associated with the one or more MTCHs.

7. A device according to any one of the preceding claims, wherein: The MDT measurement for the broadcast transmission of the one or more MBSs includes: One or more MDT measurements of broadcast transmissions associated with the one or more multicast control channels MCCH for one or more MBSs, wherein the one or more MCCHs are respectively associated with one or more multicast control channel radio network temporary identifiers MCCH-RNTI configured to the terminal device.

8. The device according to claim 7, wherein: Results of one or more MDT measurements associated with the one or more MCCHs for broadcast transmission of one or more MBSs are indexed in the MDT report based on the one or more MCCH-RNTIs associated with the one or more MCCHs.

9. The device according to any one of the preceding claims, wherein: Results of the MDT measurements for the broadcast transmission of the one or more MBSs are indexed in the MDT report based on the MBS delivery mode used for the MDT measurements.

10. The device according to any one of the preceding claims, wherein: The at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to perform the MDT measurement based on the received MDT measurement configuration by at least: The block error rate is determined after each received broadcast transmission.

11. The device according to any one of the preceding claims, wherein: The at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to perform the MDT measurement based on the received MDT measurement configuration by at least: determining a number of repetitions and / or an average number of repetitions required to decode at least one transport block of a broadcast transmission for the one or more MBSs, and / or The number of unnecessary repetitions and / or the average number of unnecessary repetitions of the at least one transport block for the broadcast transmission of the one or more MBSs is determined, the unnecessary repetitions being reception repetitions not required for decoding the at least one transport block.

12. The device according to claim 11, wherein The MDT measurement configuration includes one or more first averaging parameters, which are used to calculate an average number of repetitions required to decode the at least one transport block broadcasted for the one or more MBSs and / or an average number of unnecessary repetitions of the at least one transport block broadcasted for the one or more MBSs.

13. The device according to claim 11, wherein: The at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to perform the MDT measurement based on the received MDT measurement configuration by at least: determining at least one modulation and coding scheme used in decoding a broadcast transmission for the one or more MBSs; and / or An average modulation and coding scheme index used in decoding broadcast transmissions for the one or more MBSs is determined.

14. The device according to claim 13, wherein: The MDT measurement configuration includes one or more second average parameters, and the one or more second average parameters are used to calculate the average modulation and coding scheme index.

15. A device according to any one of the preceding claims, wherein: The MDT measurement configuration is included in a radio resource control message.

16. A device according to any one of the preceding claims, wherein: The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to: perform the MDT measurements on broadcast transmissions for the one or more MBSs when the terminal device operates in a radio resource control connected mode.

17. The device according to any one of claims 1 to 15, wherein: The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to: performing the MDT measurements on a broadcast transmission for the one or more MBSs when the terminal device is operating in a radio resource control idle or inactive mode; as well as The MDT report is sent after the terminal device switches from the radio resource control idle or inactive mode to the radio resource control connected mode.

18. A device according to any one of the preceding claims, wherein: The at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to: when the terminal device is operating in a radio resource control connected mode, in response to receiving an MDT information request from the access node or the other access node of the wireless communication network, perform the sending of the MDT report.

19. A device for an access node of a wireless communication network, the device comprising: at least one processor; as well as at least one memory including computer program code; The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least perform: An MDT measurement configuration for one or more MBSs is sent to a terminal device of the wireless communication network, wherein the MDT measurement configuration defines a configuration for the following operations of the terminal device: performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs, and forming an MDT report for sending to the access node or another access node of the wireless communication network, the MDT report including at least information about the results of the MDT measurements on the broadcast transmissions for the one or more MBSs, and indexing the results of the MDT measurements in the MDT report based on one or more cell identifiers of the one or more cells.

20. The device according to claim 19, wherein The configuration for the terminal device to perform the MDT measurements defines one or more measurements of reference signal received power RSRP and / or reference signal received quality RSRQ based on the broadcast transmission, wherein the broadcast transmission includes one or more reference signals of a predefined type.

21. The device according to claim 20, wherein: The predefined type is a synchronization signal block or a tracking reference signal.

22. The device according to claim 20 or 21, wherein: The MDT report includes information of a predefined type regarding the one or more reference signals.

23. The device according to any one of claims 19 to 22, wherein: The MDT measurement configuration defines a configuration for the terminal device to perform one or more MDT measurements on broadcast transmissions associated with one or more MTCHs for one or more MBSs, wherein the one or more MTCHs are respectively associated with one or more G-RNTIs configured to the terminal device.

24. The device according to claim 23, wherein: The MDT measurement configuration defines indexing, in the MDT report, results of one or more MDT measurements of broadcast transmissions associated with the one or more MTCHs for one or more MBSs based on the one or more G-RNTIs associated with the one or more MTCHs.

25. The device according to any one of claims 19 to 24, wherein: The MDT measurement configuration defines a configuration for the terminal device to perform one or more MDT measurements on broadcast transmissions associated with the one or more MCCHs for one or more MBSs, wherein the one or more MCCHs are respectively associated with one or more MCCH-RNTIs configured to the terminal device.

26. The device according to claim 25, wherein The MDT measurement configuration defines indexing, in the MDT report, results of one or more MDT measurements of broadcast transmissions associated with the one or more MCCHs for one or more MBSs based on the one or more MCCH-RNTIs associated with the one or more MCCHs.

27. The device according to any one of claims 19 to 26, wherein: The MDT measurement configuration defines: indexing, in the MDT report, results of the MDT measurement for the broadcast transmission of the one or more MBSs based on an MBS delivery mode used for the MDT measurement.

28. The device according to any one of claims 19 to 27, wherein The configuration for the terminal device to perform the MDT measurements defines a determination of a block error rate to be performed after each reception of a broadcast transmission.

29. The device according to any one of claims 19 to 28, wherein: The configuration definition used by the terminal device to perform the MDT measurement: determining a number of repetitions and / or an average number of repetitions required for the terminal device to decode at least one transport block for a broadcast transmission of the one or more MBSs, and / or Determine the number of unnecessary repetitions and / or the average number of unnecessary repetitions of at least one transport block for broadcast transmission of the one or more MBSs, wherein the unnecessary repetitions are reception repetitions not required for the terminal device to decode the at least one transport block.

30. The device according to claim 29, wherein: The MDT measurement configuration includes one or more first averaging parameters, which are used to calculate the average number of repetitions required for the terminal device to decode at least one transport block broadcasted for the one or more MBSs and / or the average number of unnecessary repetitions of at least one transport block broadcasted for the one or more MBSs.

31. The device according to any one of claims 19 to 30, wherein: The configuration definition used by the terminal device to perform the MDT measurement: determination of at least one modulation and coding scheme used in decoding a broadcast transmission for the one or more MBSs; and / or Determination of an average modulation and coding scheme index used in decoding broadcast transmissions for the one or more MBSs.

32. The device according to claim 31, wherein The MDT measurement configuration includes one or more second average parameters, and the one or more second average parameters are used to calculate the average modulation and coding scheme index.

33. The device according to any one of claims 19 to 32, wherein: The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to: send the MDT measurement configuration included in a radio resource control message.

34. The device according to any one of claims 19 to 33, wherein: The at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to perform: The MDT report is received from the terminal device.

35. The device according to any one of claims 19 to 34, wherein: The at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to: send an MDT information request to the terminal device before receiving the MDT report.

36. A method comprising: Receiving, by a terminal device of a wireless communication network, an MDT measurement configuration for one or more MBSs from an access node of the wireless communication network; performing, by the terminal device, MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs based on the received MDT measurement configuration; as well as An MDT report formed based on the received MDT measurement configuration is sent by the terminal device to the access node or another access node of the wireless communication network, wherein the MDT report includes at least information about the results of the MDT measurement of the broadcast transmission for the one or more MBSs, and wherein the results of the MDT measurement are indexed in the MDT report based on one or more cell identifiers of the one or more cells.

37. A computer program comprising instructions for causing an apparatus to perform at least the following operations as a terminal device in a wireless communication network: receiving, from an access node of the wireless communication network, an MDT measurement configuration for one or more MBSs; performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs based on the received MDT measurement configuration; and sending an MDT report formed based on the received MDT measurement configuration to the access node or another access node of the wireless communication network, wherein: The MDT report includes at least information on results of MDT measurements on broadcast transmissions for the one or more MBSs, and wherein the results of the MDT measurements are indexed in the MDT report based on one or more cell identifiers of the one or more cells.

38. A method comprising: An MDT measurement configuration for one or more MBSs is sent by an access node of a wireless communication network to a terminal device of the wireless communication network, wherein the MDT measurement configuration defines a configuration for the following operations of the terminal device: performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for the one or more MBSs, and forming an MDT report for sending to the access node of the wireless communication network, the MDT report including at least information about the results of the MDT measurements on the broadcast transmissions for the one or more MBSs, and indexing the results of the MDT measurements in the MDT report based on one or more cell identifiers of the one or more cells.

39. A computer program comprising instructions for causing an apparatus to perform at least the following operations as an access node of a wireless communication network: Sending an MDT measurement configuration for one or more MBSs to a terminal device of the wireless communication network, wherein: The MDT measurement configuration defines a configuration for the following operations of the terminal device: performing MDT measurements on broadcast transmissions associated with one or more cells of the wireless communication network for one or more MBSs, and forming an MDT report for sending to an access node of the wireless communication network, the MDT report including at least information about the results of the MDT measurements on broadcast transmissions for the one or more MBSs, and indexing the results of the MDT measurements in the MDT report based on one or more cell identifiers of the one or more cells.

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