Method and apparatus for measurement mode selection procedure in a communication system comprising a plurality of transmission

Abstract

An example method for selecting a measurement mode by a user equipment (UE) in a communication system including a plurality of transmit and receive points (TRPs) includes receiving, from a network entity, system information indicating one or more measurement modes supported by the network entity; selecting a measurement mode among the one or more measurement modes based on one or more UE parameters; transmitting a radio resource control (RRC) connection request for the selected measurement mode to the network entity; and receiving, from the network entity, a first RRC connection configuration for configuring the UE with the selected measurement mode in response to the transmitted RRC connection request.

Description

Technical Field

[0001] The present disclosure relates to the field of wireless communication networks, and for example, to a system and method for a measurement mode selection process in a multiple transmit and receive (TRP) scenario in a sixth generation (6G) wireless communication system. Background Art

[0002] Generally, several broadband wireless technologies have been developed to provide better applications and services to meet the growing requirements of broadband subscribers. The second generation (2G) wireless communication system has been developed to provide voice services while ensuring the mobility of users. The third generation (3G) wireless communication system supports not only voice services but also data services. In recent years, the fourth generation (4G) wireless communication system has been developed to provide high-speed data services. However, the 4G wireless communication system lacks resources to meet the growing demand for high-speed data services. This problem is solved by deploying the fifth generation (5G) wireless communication system to meet the growing demand for high-speed data services. In addition, the 5G wireless communication system provides ultra-reliability and supports low-latency applications. Research is currently underway to define the requirements, systems and frameworks of the sixth generation (6G) wireless communication system, which can address the limitations of the 5G wireless communication system and support enhanced use cases.

[0003] In 5G and 6G wireless communication systems, transmission and / or reception in terahertz band (THz) systems or millimeter wave or mid-band systems are based on narrow beams that suppress interference from neighboring base stations and extend the range of THz links. However, due to high path loss, severe shadowing and rain attenuation, reliable transmission at higher frequencies is one of the key issues that need to be overcome to make THz band wave systems a practical reality. Multiple transmission and reception (TRPs) per cell or cell-free or cell-free architectures may break the conventional design of cellular systems in which each cell or area will have multiple TRPs. Multiple TRPs together can form a large geographic area with continuous radio coverage. Each TRP can have one or more logical antennas that enable the formation of multiple beams. From the perspective of user equipment (UE), the UE is connected to the network as a whole rather than a single cell. The number of TRPs in the coverage area, cell area, specific area or cell, and the boundaries of multiple TRPs can be configured according to the network topology, UE distribution and traffic load conditions.

[0004] Considering the short coverage and narrow beam characteristics of THz frequency based cellular systems, mid-band cellular systems or millimeter wave based cellular systems, a public system with a cell-free architecture is used to provide continuous coverage or service to the UE. Under such a system, a cell can be composed of multiple TRPs on the same carrier / frequency. In addition, the UE can be under the service of one or more such TRPs in both the downlink (DL) and / or uplink (UL) directions. From the UE's perspective, it is not necessary to distinguish all such service TRPs or access points (APs) with any specific identifier, because the service TRP or AP can be just multiple sources of service beams, and any distinction between multiple TRPs can be achieved at the beam level.

[0005] Figure 1A and 1B 100 and 100' illustrate a cell-free architecture of a radio network consisting of multiple TRPs according to the prior art. Figure 1A , describes a possible deployment of a cell-free architecture, where an area or cell including multiple TRPs is connected to a TRP controller (TRP-C) 101. TRP-C 101 is connected to a control unit or C-RAN 103. C-RAN 103 is a function of a centralized unit (CU) or a CU and a distributed unit (DU), which may have a radio access network function. C-RAN 103 has a defined area or region called a cell or C-RAN area. A cell or C-RAN 103 includes multiple TRPs on the same or different carriers. Users can be served by a single TRP or multiple TRPs. TRP-C 101 is a network node that communicates with multiple TRPs and C-RAN 103. TRP-C 101 controls multiple TRPs within a cell or area defined by C-RAN 103. TRP-C 101 may be an existing network node in the network, or may be a part of an existing network node such as a CU, DU, etc. THz or high frequency millimeter wave links, mid-band or sub-6GHz may be sensitive and may easily cause problems such as blocking, deafness and switching, and affect the user experience. In order to have a fast recovery between the UE and the network, the UE can decide which TRP or TRPs can serve the UE. The main functions of TRP-C 101 include beam management, switching of master nodes / decision about master nodes, switching within and between TRPs, formation of clusters (lists of TRPs serving users) for each UE, and addition and deletion of nodes in the cluster.

[0006] refer to Figure 1B , describes another possible deployment of a cell-free architecture, where regions or cells comprising multiple TRPs of a radio network are connected to a control unit or C-RAN 103. In this scenario, TRP-C 101 is part of C-RAN 103. Figure 1B In the architecture, multiple TRPs are directly connected to the C-RAN 103 through a wired or wireless interface and are handled by the CU, DU or module TRP-C controller part of the C-RAN 103. The central unit can act as a mobility anchor point and centralized control node for multiple TRPs.

[0007] In the existing measurement mechanisms for mobility and scheduling, measurements on the UE side are mainly used. According to TS 38.300, the measurements performed by the UE for connected mode mobility are classified into at least the following four measurement types:

[0008] Intra-frequency New Radio (NR) measurements,

[0009] Inter-frequency NR measurements,

[0010] Inter-Radio Access Technology (RAT) measurements for Evolved Universal Terrestrial Radio Access (E-UTRA), and

[0011] Inter-RAT measurements for Universal Terrestrial Radio Access (UTRA).

[0012] For each measurement type, the UE receives a measurement configuration from the network. The measurement configuration includes one or more measurement objects. The one or more measurement objects may include a carrier frequency to be monitored. In addition, for each measurement object, one or more reporting configurations may be defined. The reporting configuration defines a reporting criterion (or multiple criteria). In the measurement configuration, three reporting criteria are used, namely, event-triggered reporting, periodic reporting, and event-triggered periodic reporting. In addition, the association between the one or more measurement objects and the one or more reporting configurations is created by a measurement identifier. The measurement identifier links a measurement object and a reporting configuration for the same RAT together. In addition, the UE performs measurements using multiple measurement identifiers for each of the measurement object and reporting configuration pairs according to the measurement configuration and the reporting criterion. The UE also sends the measurement report to the network for mobility and scheduling decisions.

[0013] Figure 2 is a sequence diagram 200 depicting a signaling exchange between a user equipment (UE) 201 and a radio network 203 for a conventional or existing measurement procedure according to the prior art. The sequence diagram 200 depicts a series of operational steps 205 to 217.

[0014] In step 205, a radio resource control (RRC) connection establishment is established between UE 201 and radio network 203. In step 207, UE 201 receives a measurement configuration from radio network 203. The measurement configuration includes at least one measurement object and a reporting criterion (or multiple criteria). In step 209, UE 201 performs measurements based on the measurement configuration. In step 211, UE 201 sends a measurement report to radio network 203 based on the reporting criterion. In step 213, the radio network selects a new TRP within the cell based on the measurement report. In step 215, UE 201 receives a mobility command from radio network 203 to switch to the new TRP within the cell. In step 217, UE 201 starts performing a random access channel (RACH) procedure on the new TRP within the cell.

[0015] The existing measurement process is defined for cellular-based systems, where each of the measurement configurations and reporting criteria is configured for each cell. However, in 6G wireless communication systems, there is no cell concept, and multiple TRPs will serve UEs. Considering the density of TRPs and the line-of-sight nature of 6G signals, the existing measurement mechanism will require frequent measurements and heavy signaling load due to the UE's measurement reports.

[0016] Furthermore, in the existing measurement process, if the UE relies on the network for handover, a time delay is involved when switching from one node to another. Furthermore, in the existing measurement process, it is not possible for the network to distribute measurement objects for all possible TRPs around the UE. In order to distribute the measurement objects, the RRC reconfiguration message will be long and heavy.

[0017] In addition, the existing measurement process does not have a mechanism to consider the interruption of the signal (especially mmW and 6G THz signals). In addition, the existing measurement process does not have a mechanism to consider the change of the direction of the UE. Generally, in 6G wireless communication systems, the UE is very sensitive to the direction, and even a slight change in the UE direction may significantly affect the measurement criteria in the existing measurement process.

[0018] In addition, in 6G wireless communication systems, TRPs operate in clusters, and none of the existing measurement procedures provide means for cluster configuration. In addition, none of the existing measurement procedures are adapted to separate UL and DL paths for UEs.

[0019] Therefore, new measurement mechanisms in multi-TRP scenarios are needed because existing measurement mechanisms cannot be extended to the above requirements and limitations. Summary of the invention

[0020] Solution to the problem

[0021] This summary is provided to introduce a series of concepts that are further described in the detailed description in a simplified format. This summary is neither intended to identify the key or essential concepts of the disclosure nor to determine the scope of the disclosure.

[0022] In an example embodiment, a method for selecting a measurement mode by a user equipment (UE) in a communication system including a plurality of transmit and receive points (TRPs) is disclosed. The method may include receiving system information indicating one or more measurement modes supported by the network entity from a network entity. The method may include selecting a measurement mode among the one or more measurement modes based on one or more UE parameters. The method may include sending a radio resource control (RRC) connection request for the selected measurement mode to the network entity. The method may include, in response to the sent RRC connection request, receiving from the network entity a first RRC connection configuration for configuring the UE to have the selected measurement mode.

[0023] In various example embodiments, the method may include sending UE assistance information to a network entity, the UE assistance information indicating a request to change the selected measurement mode when in the RRC_CONNECTED state. The method may include: in response to the sent UE assistance information, receiving from the network entity a second RRC connection configuration for reconfiguring the UE with the changed measurement mode.

[0024] In various example embodiments, the one or more UE parameters may include at least one of: a mobility parameter associated with the UE, a rotation parameter associated with the UE, a power level of the UE, a thermal level of the UE, and a cluster configuration of the UE. Information corresponding to the cluster configuration of the UE may, for example, indicate whether the UE is configured with a cluster of TRPs.

[0025] In various example embodiments, the one or more measurement modes may include a first measurement mode, a second measurement mode, a third measurement mode, and a mixed mode.

[0026] In various example embodiments, to select a measurement mode among one or more measurement modes, the method may include selecting a third measurement mode as the measurement mode based on one of determining that a UE power level is less than a threshold power level, determining that a UE thermal level is greater than a threshold level, or determining that the UE is not cluster configured and that UE mobility is greater than a threshold value.

[0027] In various example embodiments, in a third measurement mode, the method may include receiving a measurement configuration from a network entity. The method may include sending UE location information and an uplink sounding reference signal (UL SRS) of the UE to the network entity. The method may include, in response to the sent location information and the UL SRS, receiving a mobility command from the network entity to switch to a new TRP selected by the network entity, wherein the selection of the new TRP is based on the UE location information and the UL SRS.

[0028] In various example embodiments, in a third measurement mode, the method may include receiving information related to triggering an event associated with a reporting criterion from a network entity. The information related to the triggering event may include information associated with triggering of a first event, and the first event is triggered when an uplink channel quality of the UE becomes less than a threshold channel quality. The method may include reporting the triggered first event to the network entity when the uplink channel quality becomes less than the threshold channel quality. The method may include sending the UE location information and the UL SRS to the network entity when reporting the triggered first event to the network entity.

[0029] In various example embodiments, in order to select a measurement mode among one or more measurement modes, the method may include: selecting a second measurement mode as the measurement mode based on determining that a UE power level is greater than a threshold power level or a UE thermal level is less than a threshold level, and determining that the UE is clustered with a TRP.

[0030] In various example embodiments, in the second measurement mode, the method may include receiving a measurement configuration and cluster information associated with the plurality of TRPs from the network entity. The method may include determining and selecting a new TRP from the plurality of TRPs based on the received measurement configuration and cluster information. The method may include sending a signal to the network entity notifying a switch of a downlink (DL) path to the new TRP.

[0031] In various example embodiments, in the second measurement mode, the method may include receiving information related to triggering an event associated with the reporting criteria from the network entity. The information related to the triggering event may include information associated with the triggering of a first event and a second event. The first event may be triggered when the new TRP resource becomes better than a threshold, and the second event may be triggered when the new TRP resource becomes better than the configured TRP resource offset. The method may include reporting the triggered first event and the triggered second event to the network entity. The method may include: when reporting the triggered first event and the triggered second event to the network entity, sending a signal to the network entity notifying a switch of a downlink (DL) path to the new TRP.

[0032] In various example embodiments, to select a measurement mode among one or more measurement modes, the method may include selecting a hybrid mode as the measurement mode based on determining that a UE power level is greater than a threshold power level or a UE thermal level is less than a threshold level, determining that UE mobility is less than a threshold, and determining that the UE needs to be moved in the hybrid mode.

[0033] In various example embodiments, to select the measurement mode among the one or more measurement modes, the method may further include selecting the first measurement mode as the measurement mode based on unavailability of other measurement modes except the first measurement mode among the one or more measurement modes.

[0034] In various example embodiments, in a first measurement mode, the method may include receiving a measurement configuration from a network entity. The method may include performing measurements based on the received measurement configuration. The method may include sending a measurement report of the performed measurements to the network entity. The method may include receiving, in response to the sent measurement report, a mobility command from the network entity to switch to a new TRP, wherein the new TRP is selected based on the measurement report.

[0035] In an example embodiment, a user equipment (UE) may include a transceiver and at least one processor coupled to the transceiver. The at least one processor may be configured to receive system information indicating one or more measurement modes supported by the network entity from a network entity. The at least one processor may be configured to select a measurement mode among the one or more measurement modes based on one or more UE parameters. The at least one processor may be configured to send a radio resource control (RRC) connection request for the selected measurement mode to the network entity. The at least one processor may receive, in response to the sent RRC connection request, a first RRC connection configuration for configuring the UE with the selected measurement mode from the network entity.

[0036] In order to further illustrate the advantages and features of the present disclosure, a more specific description is provided with reference to specific embodiments thereof, which are shown in the accompanying drawings. It should be understood that these drawings depict only non-limiting example embodiments and therefore should not be considered to limit the scope of the present disclosure in any way. Additional features and details will be used in the drawings to describe and explain the example embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] These and other features, aspects and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings, in which like characters refer to like parts throughout the several views, and in which:

[0038] Figure 1A and 1B is a diagram depicting a cell-free architecture of a radio network including a plurality of transmit-receive points (TRPs) according to the prior art;

[0039] Figure 2 is a sequence diagram depicting a signaling exchange between a user equipment (UE) and a radio network for a conventional measurement procedure according to the prior art;

[0040] Figure 3A , Figure 3B and Figure 3C Several example measurement patterns for handling UE mobility and scheduling in a multi-TRP scenario according to various embodiments are shown;

[0041] Figure 4 is a sequence diagram depicting an example method of selecting a measurement mode at a UE in a multi-TRP scenario according to various embodiments;

[0042] Figure 5 is a flow chart depicting an example selection of a measurement mode among multiple measurement modes at a UE in a multi-TRP scenario according to various embodiments;

[0043] Figure 6 is a flow chart depicting example UE actions for each of a plurality of measurement mode configurations according to various embodiments;

[0044] Figure 7 is a diagram depicting one or more example reference signals for multiple measurement mode configurations according to various embodiments;

[0045] Figure 8 is a flow chart depicting example UE actions when the network configures the UE with events T1 and T2 according to various embodiments;

[0046] Fig. 9 An example scenario is shown in which a UE is configured with events T1 and T2 according to various embodiments;

[0047] Fig.10 is a flow chart depicting example UE actions when the network configures the UE with events T3 and T4 according to various embodiments;

[0048] Fig.11A and 11B An example scenario is shown in which a UE is configured with events T3 and T4 according to various embodiments;

[0049] Fig.12 is a flow chart depicting example UE actions when the network configures the UE with event T5 according to various embodiments;

[0050] Fig.13 An example scenario is shown in which a UE is configured with event T5 according to various embodiments;

[0051] Fig.14 is a sequence diagram depicting an example method of configuring separate uplink (UL) and downlink (DL) paths for a UE according to various embodiments; and

[0052] Fig.15 is a block diagram depicting a configuration of an example UE in a wireless communication system according to various embodiments.

[0053] Furthermore, those skilled in the art will appreciate that those elements in the drawings are shown for simplicity and may not necessarily be drawn to scale. For example, a flow chart illustrates the method in terms of the steps involved to help improve understanding of various aspects of the present disclosure. Furthermore, with respect to the construction of the apparatus, one or more components of the apparatus may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details relevant to understanding the embodiments of the present disclosure so as not to obscure the drawings with details that would be readily apparent. DETAILED DESCRIPTION

[0054] For the purpose of promoting an understanding of the principles of the present disclosure, reference will now be made to the example embodiments illustrated in the drawings, and specific language will be used to describe these example embodiments. It will be understood, however, that no limitation of the scope of the present disclosure is intended thereby, and such alterations and further modifications in the illustrated systems, and further applications of the principles of the present disclosure as illustrated therein, are contemplated.

[0055] Those skilled in the art will understand that the foregoing general description and the following detailed description are illustrative of the present disclosure and are not intended to limit the present disclosure.

[0056] References throughout this specification to "aspect," "another aspect," or similar language mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one example embodiment of the present disclosure. Thus, appearances of the phrases "in an embodiment," "in one or more embodiments," "in another embodiment," and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0057] The terms "comprise", "comprising" or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process or method that includes a list of steps includes not only those steps but may also include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or subsystems or elements or structures or components preceded by "comprises ..." do not preclude the presence of other devices or other subsystems or other elements or other structures or other components or additional devices or additional subsystems or additional elements or additional structures or additional components without more constraints.

[0058] The example embodiments of this article and their various features and advantageous details are explained more fully with reference to the non-limiting embodiments shown in the drawings and described in detail in the following description. The description of known components and processing techniques may be omitted so as not to unnecessarily obscure the embodiments of this article. In addition, the various example embodiments described herein are not necessarily mutually exclusive, because some embodiments may be combined with one or more other embodiments to form new embodiments. Unless otherwise stated, the term "or" as used herein refers to non-exclusiveness. The examples used herein are intended only to facilitate understanding of the manner in which the embodiments of this article may be practiced, and further enable those skilled in the art to practice the embodiments of this article. Therefore, the examples should not be interpreted as limiting the scope of the embodiments of this article.

[0059] As conventional in the art, embodiments can be described and illustrated according to a module or engine that performs one or more functions described. These modules or engines (which may be referred to herein as, for example, a unit or block, etc., or may include a block or unit) are physically implemented by analog or digital circuits (such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hard-wired circuits, etc.), and may be optionally driven by firmware and / or software. The circuit may be, for example, embodied in one or more semiconductor chips, or embodied on a substrate support such as a printed circuit board. The circuit included in the block may be implemented by dedicated hardware, by a processor (e.g., one or more programmed microprocessors and associated circuits) or by a combination of dedicated hardware that performs some functions of the block and a processor that performs other functions of the block. Without departing from the present disclosure, each block of the embodiment may be physically divided into two or more interactive and discrete blocks. Similarly, without departing from the present disclosure, the block of the embodiment may be physically combined into more complex blocks.

[0060] The accompanying drawings are used to help easily understand various technical features, and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. Therefore, the present disclosure should be interpreted as extending to any changes, equivalents and substitutes other than those specifically set forth in the accompanying drawings. Although the terms first, second, etc. can be used herein to describe various elements, these elements should not be limited by these terms. These terms are usually only used to distinguish one element from another element.

[0061] Embodiments will be described in detail below with reference to the accompanying drawings.

[0062] In one or more embodiments, the method disclosed herein uses one or more measurement modes to provide greater flexibility in measurement. In an embodiment, the UE may choose to use a traditional measurement process including a measurement report of moving to a new cell, or may choose not to perform measurement and reporting. The UE may also select a measurement mode in one or more measurement modes, wherein the selection of the measurement mode is based on one of the following: a mobility constraint, a power constraint, a thermal constraint, or other constraints of the UE.

[0063] In one or more example embodiments, the disclosed method introduces new measurement events to provide the UE with flexibility to not perform and report measurements. For example, one of the new measurement events allows the UE to simply measure and switch to a new transmit and receive point (TRP), while another event triggers the broadcast of an uplink sounding reference signal (UL SRS) that is used by the network to switch the UE's uplink (UL) / downlink (DL) path. At least one of the new measurement events is introduced to track and / or report the occurrence of a signal outage or directional impact on the network, or to immediately take action to measure and select another TRP.

[0064] In one or more example embodiments, the disclosed method allows the UE to operate in a hybrid measurement mode so that the UE can select different TRPs for UL and DL to solve the problem of UL and DL imbalance.

[0065] Figure 3A , 3B and 3C illustrate multiple measurement modes 300, 300', and 300" for handling UE mobility and scheduling in a multi-TRP scenario according to one or more example embodiments disclosed herein.

[0066] In one or more example embodiments, in order to handle the mobility and scheduling of the multi-TRP mechanism, three measurement modes are defined. Figure 3A Mode 1 of the three measurement modes is shown. Mode 1 is a measurement-based mode or a legacy mode. Similar to a legacy LTE / NR system, a measurement-based mode for handling UE mobility and scheduling is preferred for UE 301 with little or no mobility. In Mode 1, UE 301 can perform measurements and send reports to the network 303.

[0067] like Figure 3A As shown, in step 305, UE 301 receives a measurement configuration from network 303. The measurement configuration includes at least one measurement object and a reporting criterion. In step 307, UE 301 performs measurements based on the received measurement configuration. In step 309, UE 301 sends a measurement report of the performed measurements to network 303 based on the reporting criterion. In step 311, in response to the sent measurement report, UE 301 receives a mobility command from network 303 to switch to a new TRP. The new TRP is selected based on the measurement report.

[0068] Figure 3BMode 2 of the three measurement modes is shown. Mode 2 is a free measurement report mode or measurement that does not report mobility. In Mode 2, UE 301 may not send any measurement report to network 303 to perform mobility. For example, Mode 2 may be used by UE 301 with medium mobility. Mode 2 may also be used by UEs operating within a TRP cluster, where all access points are in UL sync. For such a situation, UE 301 may measure the DL signal and decide to change the TRP independently, and thereafter notify the network 303 to switch the DL path.

[0069] like Figure 3B As shown, in step 313, UE 301 receives measurement configuration and cluster information associated with multiple TRPs from current TRP 303-1. In step 315, UE 301 determines and selects a new TRP among the multiple TRPs based on the received measurement configuration and cluster information. In step 317, UE 301 sends a signal to network 303 to notify the switching of the downlink (DL) path to the new TRP 303-3.

[0070] Figure 3C Mode 3 of the three measurement modes is shown. Mode 3 is a no-measurement mode. Mode 3 may be used, for example, by fast-moving UEs or by UEs with low measurement accuracy. In Mode 3, UE 301 does not perform any measurements but relies on the network 303 to move UE 301 to a new TRP. UE 301 may select a new TRP based on the GPS location, or the network 303 may perform the switch based on the GPS location reported by UE 301 and the UL SRS of the UE.

[0071] like Figure 3C As shown, at step 319, UE 301 receives a measurement configuration from network 303. At step 321, UE 301 sends UE location information and an uplink sounding reference signal (UL SRS) of UE 301 to network 303. At step 323, in response to the sent location information and UL SRS, UE 301 receives a mobility command from network 303 to switch to a new TRP selected by network 303. The selection of the new TRP is based on the UE location information and UL SRS.

[0072] Figure 4 is a sequence diagram depicting a method 400 of selecting a measurement mode at a UE 301 in a multi-TRP scenario according to various embodiments.

[0073] Specifically, Figure 4A signaling exchange between UE 301 and network 303 is depicted to select a measurement mode. In step 401, UE 301 receives system information (SIB) from network 303. The SIB information indicates one or more measurement modes supported by network 303. The format of the signaling message for signaling SIB information may be given as:

[0074] SystemInformationBlockTypeX

[0075] {

[0076] measurementMode supported / not supported;

[0077] measurementMode{mode1,mode2,mode3};

[0078] }

[0079] An example of a signaling message for signaling SIB information indicating support for Mode 3 may be given as:

[0080] Example: measurementMode supported

[0081] measurementMode{0,0,1}.

[0082] In step 403, UE 301 broadcasts the measurement modes supported by UE 301 by means of UE capability exchange or via UE capability OTA message. UE capability exchange indicates UE 301's support for the measurement mode.

[0083] At step 405, UE 301 selects a measurement mode among three measurement modes based on one or more UE parameters. In a non-limiting example, UE 301 may select a measurement mode based on mobility requirements or other UE-side intelligence.

[0084] At step 407, UE 301 sends a radio resource control (RRC) connection request for the selected measurement mode to network 303. In a non-limiting example, if UE 301 requests mode 2, the format of the signaling message for signaling the RRC connection request may be given as:

[0085] message c1:rrcConnectionRequest:

[0086] {

[0087] establishmentCause mo-Data,

[0088] measurementMode mode2,

[0089] spare'0'B

[0090] }

[0091] }.

[0092] At step 409, in response to the sent RRC connection request, UE 301 receives a first RRC connection configuration for configuring UE 301 in the selected measurement mode from network 303. The format of the signaling message for signaling the RRC connection configuration may be given as:

[0093] message c1:rrcConnectionReconfiguration:

[0094] {

[0095] rrc-TransactionIdentifier 1,

[0096] criticalExtensions c1:rrcConnectionReconfiguration-r8:

[0097] {

[0098] measConfig

[0099] {

[0100] measurementMode mode2,

[0101] }.

[0102] At step 411, UE 301 changes the measurement mode while remaining in the RRC_CONNECTED state. The change in measurement mode may be based on one or more UE parameters. In a non-limiting example, in the case where some applications require seamless service, UE 301 may request to change the measurement mode to minimize delays in the service.

[0103] At step 413, UE 301 sends UE assistance information to network 303. The UE assistance information indicates a request to change the selected measurement mode when connected to network 303 in RRC connected state. The format of the signaling message for signaling UE assistance information can be given as:

[0104] UE-Measurement-mode::=SEQUENCE{mode1,mode2,mode3}.

[0105] At step 415, in response to the transmitted UE assistance information, UE 301 receives a second RRC connection configuration from network 303 for reconfiguring UE 301 with a changed measurement mode.

[0106] Figure 5 5 is a flowchart 500 depicting selecting a measurement mode among multiple measurement modes at a UE 301 in a multi-TRP scenario according to various embodiments.

[0107] UE 301 may select a measurement mode in one or more measurement modes based on one or more UE parameters. The one or more UE parameters may include, but are not limited to, one of the following: mobility parameters associated with UE 301, delay tolerance of slices and applications running in UE 301, UE power level, UE thermal level, TRP density at a given location, signal conditions at a given location, or UE cluster configuration information.

[0108] The flow of the example method for selecting a measurement mode starts at step 501. At step 501, UE 301 receives system information (SIB) from network 303. The SIB information indicates one or more measurement modes supported by network 303.

[0109] At step 503, UE 301 determines at least one of a UE power level or a UE thermal level. UE 301 may determine, for example, whether the UE power level is less than a threshold power level or whether the UE thermal level is greater than a threshold thermal level.

[0110] At step 505, UE 301 selects a third measurement mode (mode 3) as the measurement mode based on determining that the UE power level is less than a threshold power level or determining that the UE thermal level is greater than a threshold thermal level. The third measurement mode is a low power consumption mode (e.g., a minimum power consumption mode) because the third measurement mode allows UE 301 to turn off measurement.

[0111] At step 507, if it is determined at step 503 that the UE power level is greater than the threshold power level or the UE thermal level is determined to be less than the threshold thermal level, the UE 301 determines whether the UE 301 is configured with a cluster of TRPs. If the UE 301 is configured with a cluster of TRPs sharing the same UL sync, the UE 301 can, for example, freely switch its DL TRP to a TRP belonging to the same cluster without re-performing a random access procedure (RACH).

[0112] At step 509, UE 301 selects the second measurement mode as the measurement mode based on determining that the UE power level is greater than the threshold power level or the UE thermal level is less than the threshold thermal level and determining that UE 301 is cluster-configured with a cluster of TRP. The second measurement mode is suitable for conditions where, for example, UE 301 may not require network assistance when switching.

[0113] In step 511, if it is determined in step 507 that UE 301 is not configured with a cluster of TRP, UE 301 determines at least one of the mobility parameters associated with UE 301, the delay tolerance (e.g., interruption) of the slice and application running in UE 301, or the signal condition (e.g., low measurement accuracy) at a given location.

[0114] At step 513, UE 301 selects the third measurement mode as the measurement mode based on at least one of determining that UE 301 is not cluster configured, that the UE mobility parameter indicates that the UE mobility is greater than a threshold mobility value, or determining that low measurement accuracy is required. In a non-limiting example, if UE 301 is highly mobile or has very low measurement accuracy, or cannot stay on the TRP due to signal interruption, UE 301 can leave the TRP selection to the network 303 and remain connected in the third measurement mode.

[0115] At step 515, if it is determined at step 511 that the UE mobility is less than the threshold mobility value or the delay tolerance of the slice and application is low or high measurement accuracy is required, the UE 301 determines whether it is necessary to move the UE 301 in the hybrid mode.

[0116] In a non-limiting example, UE 301 may determine to operate in hybrid mode in the event that UE 301 needs to have separate UL and DL TRPs. UE 301 may also need separate UL and DL TRPs when UE 301 identifies that a first TRP is best for UL (e.g., the first TRP has a lower path loss and a lower TX power that needs to be achieved) and a second TRP is better for DL ​​(e.g., the second TRP has a better DL metric, such as RSRP and SNR).

[0117] At step 517, UE 301 selects hybrid mode as the measurement mode based on the UE mobility parameter indicating that the UE mobility is less than the threshold mobility value and determining that the UE 301 needs to be moved in the hybrid mode.

[0118] In step 519, if each of the second measurement mode, the third measurement mode, and the hybrid mode is unavailable, the UE 301 selects the first measurement mode.

[0119] Figure 6is a flow chart 600 depicting example UE actions for each of a plurality of measurement mode configurations according to various embodiments.

[0120] In step 601 , UE 301 and network 303 exchange signaling to configure a measurement mode. Network 303 sends the measurement mode configuration in RRC connection configuration message 409 , for example.

[0121] In step 603, it is determined whether the measurement mode configuration is a measurement-based addition configuration. The measurement-based addition configuration is a mode 1 configuration. If it is determined that the measurement mode configuration is a measurement-based addition configuration (mode 1), the process proceeds to step 605, otherwise, the process proceeds to step 607.

[0122] At step 605 , UE 301 may perform measurements, report the measurements to network 303 , and wait to receive a network command from network 303 .

[0123] At step 607, UE 301 determines whether the measurement mode configuration is a no measurement report configuration. The no measurement report configuration is a mode 2 configuration. At step 607, if it is determined that the measurement mode configuration is a no measurement report configuration (mode 2), the process proceeds to step 609, otherwise, the process proceeds to step 611.

[0124] At step 609, the UE 301 may perform measurements and jump to a better TRP, for example, sharing the same UL sync. The UE 301 may also perform DL measurements and may automatically switch to the best available TRP.

[0125] In step 611, UE 301 determines whether the measurement mode configuration is a no measurement configuration. The no measurement configuration is a mode 3 configuration. If it is determined in step 611 that the measurement mode configuration is a no measurement configuration (mode 3), the process proceeds to step 613, otherwise, the process proceeds to step 621.

[0126] At step 613 , UE 301 determines whether GPS-based addition is configured. If it is determined at step 613 that GPS-based addition is configured, the process proceeds to step 615 , otherwise, the process proceeds to step 617 .

[0127] In step 615, UE 301 uses the active learning model and fingerprints the location of a specific TRP. UE 301 can also use the database for future reference to switch to a specific TRP when UE 301 is present at the location coordinates of a specific TRP. Alternatively, UE 301 can report the GPS location of the UE to the network 303 and wait for the network 303 to switch UE 301 to a better TRP.

[0128] In step 617 , the UE 301 determines whether a UL SRS-based handover is being performed. If it is determined in step 617 that a UL SRS-based handover is being performed, the process proceeds to step 619 , otherwise, the process proceeds to step 621 .

[0129] In step 619, UE 301 may signal the UL SRS signal and the GPS location of the UE to network 303 and wait for network 303 to switch UE 301 to a better TRP. Network 303 may select a better TRP based on, for example, the UL SRS signal.

[0130] In step 621, if the measurement configuration is not determined in any of the above steps 601 to 619, it is determined that the configuration is invalid.

[0131] Figure 7 is a diagram 700 depicting one or more example reference signals for multiple measurement mode configurations in accordance with various embodiments.

[0132] A reference signal is a predefined signal that occupies, for example, a specific resource element within the downlink time-frequency grid. One or more reference signals are exchanged between UE 301 and network 303 for different purposes. UE 301 can report the strength of one or more reference signals to network 303 and enable network 303 to learn the channel quality of the UE. A DL reference signal is a signal for UE 301 to measure and report, while a UL reference signal is a signal sent by UE 301 to network 303 for estimating the quality of the UE's UL path.

[0133] One or more reference signals used in determining the UE's action on the measurement mode include a TRP synchronization signal (TSS) 701, a TRP reference signal (TRP-RS) 703, and a TRP uplink sounding reference signal (UL SRS) 705.

[0134] TSS is used for downlink synchronization and estimates cell power. As in 5G wireless communication systems, TRP-RS is used for channel state estimation. TRP-RS signals can be periodic, aperiodic, or semi-persistent. TRP-RS signals are used for RSRP measurements during mobility and beam changing procedures. As in 5G wireless communication systems, UL SRS is used for UL channel estimation. Network 303 provides UE-specific configuration for transmission of SRS.

[0135] In addition, measurement event configuration for a 6G wireless communication system will be described according to various embodiments.

[0136] In any measurement configuration, network 303 needs to allow UE 301 to report serving cell signal quality and neighbor cell signal quality and trigger handover with a single measurement. However, in practice, triggering handover with a single measurement may cause an overload condition due to unnecessary measurement reporting and frequent handovers.

[0137] To avoid this, the 3GPP specification has introduced a predefined set of measurement reporting mechanisms to be performed by the UE 301. Each of these predefined measurement reporting mechanisms is called an "event". The type of "event" that the UE 301 must report is specified by the RRC signaling message sent by the network 303.

[0138] The 3GPP specification introduces the following events as shown in Table 1:

[0139]

Table 1

[0140]

[0141] Events A1-A6 are the same as RAT events, and B1-B2 are the same as inter-RAT events. UE 301 continues to measure serving cell and neighbor cell parameters and validates events using thresholds or offsets defined in the reporting configuration. The reported quantity / trigger of an event can be reference signal received power (RSRP), reference signal received quality (RSRQ), or signal-to-noise ratio (SINR). If the conditions are met, an event report must be sent to the network 303.

[0142] In addition, in the 6G wireless communication system, some additional events are needed so that the UE 301 can support all measurement modes. In addition, in order to address some other shortcomings of the traditional measurement system, such as not considering interruption or direction effects, new events are described. In addition, events can also be used to activate the transmission of UL SRS for no measurement mode according to SRS transmission to reduce operating costs.

[0143] Examples of such additional events are shown in Table 2:

[0144]

Table 2

[0145]

[0146]

[0147] Figure 8 is a flow chart 800 depicting example UE actions when the network 303 configures the UE 301 with events T1 and T2 according to various embodiments.

[0148] Events T1 and T2 are used to inform the network 303 that the UE 301 has switched to a new TRP in measurement mode 2. In step 801, the UE 301 is configured in measurement mode 2. In step 803, the network 303 sends a measurement configuration to the UE 301. The measurement configuration includes cell cluster information of a cluster of TRPs.

[0149] At step 805, the network 303 configures the UE 301 with event T1 and event T2. The network 303 sends information about triggering configured events T1 and T2. The UE 301 receives information about triggering of events T1 and T2 from the network 303. Event T1 is triggered when the new TRP resource becomes better than a first threshold, and event T2 is triggered when the new TRP resource becomes better than a configured TRP resource offset.

[0150] An example format of a signaling message for signaling event T1 and event T2 may be given as:

[0151] Event T1:

[0152] SNR_neighbour>SNR_threshold

[0153] Switch to neighbour TRP (switch to neighbor TRP);

[0154] Event T2:

[0155] SNR_neighbour>SNR_current+offset

[0156] Switch to neighbour TRP,

[0157] where SNR_neighbour is the signal-to-noise ratio of the strongest neighbor found, and

[0158] SNR_Current is the signal-to-noise ratio of the current serving cell.

[0159] In step 807, UE 301 performs measurements using TRP-RS 703 and then switches to the best TRP.

[0160] In step 809, UE 301 sends a measurement report to network 303 to report the triggering of event T1 and / or event T2 to network 303. When reporting the triggered event T1 and / or event T2 to network 303, UE 301 may send a signal notifying the switching of the DL path to the new TRP to network 303. In the case of event T1 and event T2, an example format of signaling information for signaling the measurement report may be given as:

[0161] value UL-DCCH-Message::=

[0162] {

[0163] message C1:measurementReport:

[0164] {

[0165] criticalExtensions c1:measurementReport-r8:

[0166] {

[0167] SelectedTRPID:TRP 2;

[0168] measResults

[0169] {

[0170] measld 8,

[0171] measResultPCell

[0172] {

[0173] rsrpResult 38,

[0174] rerqResult 15

[0175] }.

[0176] Fig. 9 An example scenario 900 is shown in which a UE 301 is configured with events T1 and T2 according to various embodiments. Fig. 9 In the example, UE 301 is configured in measurement mode 2. In addition, UE 301 is configured with event T1 and event T2 by network 303.

[0177] Initially, UE 301 is connected to TRP-1 303-1. When UE 301 moves from TRP-1 303-1 to TRP-2 303-3, it first reaches point P1. At point P1, the signal-to-noise ratio of TRP-2 303-3 becomes greater than a first threshold SNR value, or the RSRP of TRP-2 303-3 becomes greater than a first threshold RSRP value. Then, UE 301 reports event T1 to network 303.

[0178] As UE 301 moves further into TRP-2 303-3, it first reaches point P2. At point P2, the signal-to-noise ratio of TRP-2 303-3 becomes better than the first threshold SNR value. Then, UE 301 reports event T2 to network 303. At point P3, UE 301 switches to TRP2 and notifies network 303.

[0179] Fig.10 is a flow chart 1000 depicting example UE actions when the network 303 configures the UE 301 with events T3 and T4 according to various embodiments.

[0180] Event T3 allows the network 303 to monitor signal interruption due to non (line of sight) LoS. Event T4 is to allow the UE 301 to report a decrease in RSRP due to a change in the orientation / direction of the UE 301. In step 1001, the UE 301 is configured in one of Mode 1 or Mode 2 of measurement. In step 803, the network 303 sends a measurement configuration to the UE 301.

[0181] At step 1003, the network 303 configures the UE 301 with events T3 and / or T4. The network 303 sends information related to triggering the configured events T3 and / or T4 to the UE 301. The UE 301 receives information related to triggering of events T3 and / or T4 from the network 303. Event T3 is triggered when the interruption of signal quality becomes worse than a second threshold (e.g., RSRP threshold, SNR threshold, RLF threshold, etc.), and event T4 is triggered when the signal quality becomes worse than a third threshold due to a change in the direction of the UE 301.

[0182] An example format of a signaling message for signaling event T3 may be given as:

[0183] Eventld Event T3

[0184] {

[0185] threshold-disruption-RSRP:value;

[0186] threshold-disruption-SNR:value;

[0187] threshold-disruption-RLF:value;

[0188] }

[0189] Furthermore, an example format of a signaling message for signaling event T4 may be given as:

[0190] Eventld Event T4

[0191] {

[0192] threshold-direction:value;

[0193] threshold-orientation:value;

[0194] }.

[0195] At step 1005 , in measurement mode 1 UE 301 monitors event T3 and / or event T4 and reports event T3 and / or event T4 to network 303 .

[0196] In step 1007, in measurement mode 2, UE 301 selects a new TRP and transmits a signal notifying a DL path switch to the new TRP when reporting one of event T3 or event T4.

[0197] At step 1009, in measurement mode 1, the network 303 moves the UE 301 to the next best TRP when one of the events T3 or T4 is reported. The next best TRP may be understood as the best TRP with respect to the measurement except the current TRP.

[0198] Fig.11A and 11B Example scenarios 1100, 1100' are shown according to various embodiments, where UE 301 is configured with events T3 and / or T4. Fig.11A and 11B In the embodiment, UE 301 is configured in one of measurement mode 1 or mode 2. In addition, UE 301 is configured with event T3 and / or event T4 by network 303. Event T3 is triggered when the interruption of signal quality becomes worse than the second threshold. Event T4 is triggered when the signal quality becomes worse than the third threshold due to the change of the direction of UE 301.

[0199] exist Fig.11A In FIG. 3 , UE 301 is connected to TRP-1 303-1. Fig.11AAs shown, the RSRP of TRP-1 303-1 decreases due to an object blocking the LoS of TRP-1 303-1. At this time, when the RSRP of TRP-1 303-1 drops below the RSRP of TRP-2 303-3, event T3 may be triggered. UE 301 reports the triggering of event T3 to network 303 and moves to TRP-2 303-3.

[0200] exist Fig. 11B , UE 301 is connected to TRP-1 303-1. When the orientation of UE 301 changes from position A to B, event T4 is triggered. UE 301 reports the triggering of event T4 to network 303 and moves to TRP-2 303-3.

[0201] Fig.12 is a flow chart 1200 depicting example UE actions when the network 303 configures the UE 301 with event T5 according to various embodiments.

[0202] Event T5 allows UE 301 to broadcast SRS when the UL metric becomes weaker than a fourth threshold. At step 1201, UE 301 is configured for measurement mode 3. At step 1203, network 303 sends measurement configuration to UE 301. At step 1203, network 303 configures UE 301 with only event T5. Network 303 sends information related to the triggering of configured event T5 to UE 301.

[0203] An example format of a signaling message for signaling event T5 may be given as:

[0204] Eventld Event T5

[0205] {

[0206] threshold-UL BLER:value;

[0207] threshold-TX power:value;

[0208] threshold-Pathloss:value;

[0209] }.

[0210] At step 1205, UE 301 monitors the block error rate (BLER), path loss, and TX power parameters of the UL channel quality.

[0211] At step 1207, UE 301 issues an event report when event T5 occurs. UE 301 may send a measurement report to network 303. In the case of event T5, an example format of a signaling message to a signaling measurement report may be given as:

[0212] value UL-DCCH-Message::=

[0213] {

[0214] message C1:measurementReport:

[0215] {

[0216] criticalExtensions c1:measurementReport-r8:

[0217] {

[0218] Event T5:UL parameter which triggered it

[0219] }.

[0220] In step 1209, UE 301 transmits a UL SRS of UE 301. In step 1211, network 303 evaluates the UL SRS of the UE and moves UE 301 to an optimal TRP.

[0221] Fig.13 An example scenario 1300 is shown in which a UE 301 is configured with event T5 according to various embodiments. Fig.13 In the measurement mode 3, UE 301 is configured as measurement mode 3. In addition, UE 301 is configured with event T5 by network 303. When the uplink channel quality of UE 301 becomes less than a threshold channel quality, event T5 is triggered.

[0222] Initially, UE 301 is connected to TRP-1 303-1. When UE 301 moves from TRP-1 303-1 to TRP-2 303-3, UE 301 first reaches point P1. At point P1, the uplink channel quality of UE 301 becomes less than the threshold channel quality. At point P1, UE 301 starts to send GPS location information and UL SRS to network 303.

[0223] At point P2, the network 303 moves the UE 301 to TRP-2 303-3 by means of a reconfiguration or beam changing procedure.

[0224] Fig.14 is a sequence diagram depicting a method 1400 of configuring separate UL and DL paths for a UE 301 according to various embodiments.

[0225] In a multi-TRP system, the best DL TRP is not necessarily the best TRP for UL. Due to the LoS nature of the THz system and the impact of multipath, the network 303 can be better connected to the UE 301 through different TRPs. In addition, the UE 301 can use TRP-1 303-1 because the UL metric is more suitable for UL, and can use TRP-2 303-3 with a better DL metric than TRP-1 303-1.

[0226] To determine the best UL and DL channels for the UE, the network 303 may use a hybrid mode where T1, T2, and T5 are all configured at the same time. The hybrid mode may allow the UE 301 to switch to the correct TRP for DL ​​based on T1 / T2 / T3 / T4, and also report T5 at the same time, so that the network 303 provides a new UL TRP.

[0227] The method 1400 starts at step 1401, and at step 1401, the UE 301 receives system information (SIB) from the network 303. The SIB carries an SRS broadcast configuration that tells the UE 301 when the SRS can be broadcast.

[0228] At step 1403, UE 301 sends an RRC connection request to network 303. UE 301 may indicate Mode 2 and Mode 3 as preferences in the RRC connection request. Upon receiving the RRC connection request, network 303 recognizes that UE 301 is operating in hybrid mode.

[0229] At step 1405, UE 301 starts a random access procedure (RACH). At step 1407, network 303 configures UE 301 with events T1, T2, T3, and T4. At the same time, at step 1409, UE 301 broadcasts a UL SRS signal. UE 301 broadcasts UL SRS to all TRPs in the cluster so that the TRP controller can estimate which is the best UL path for UE 301.

[0230] In step 1411, UE 301 monitors events T1 to T4. UE 301 selects the best DL TRP using the triggering of events T1 to T4.

[0231] At step 1413, UE 301 may send a measurement report to network 303. UE 301 may signal network 303 to switch to the best DL TRP. Once the TRP controller has identified the best TRP for the UE's UL, UE 301 may configure the DL and UL paths accordingly in the RRC reconfiguration.

[0232] At step 1415, the network 303 sends an RRC reconfiguration message with separate UL and DL paths, and the network 303 configures the UE 301 with event T5.

[0233] At step 1417, UE 301 monitors event T5. If the quality of the UE's UL path is deteriorating, UE 301 may immediately broadcast a UL SRS to all TRPs in the cluster, and the TRP controller may again estimate the best UL path for UE 301. At step 1419, UE 301 broadcasts a UL SRS signal to all TRPs when event T5 is triggered.

[0234] Fig.15 is a block diagram 1500 depicting a configuration of an example UE 301 in a wireless communication system according to various embodiments. Fig.15 The configuration of the UE 301 may be understood as a part of the configuration of the UE 301. Hereinafter, it should be understood that the terms including "unit" or "module" may ultimately refer to a unit for processing at least one function or operation, for example, and may be implemented in hardware, software, or a combination of hardware and software.

[0235] refer to Fig.15 , UE 301 may include at least one processor 1501, a communication unit 1503 (e.g., a communicator or a communication interface or a communication circuit), and a storage unit (e.g., a memory 1505). As an example, UE 301 may be a user device such as a cellular phone or other device that communicates over multiple cellular networks (such as 3G, 4G, 5G or pre-5G, 6G networks, or any future wireless communication networks). The communication unit 1503 may perform functions for sending and receiving signals via a wireless channel.

[0236] As an example, the processor 1501 may be a single processing unit or multiple units, all of which may include multiple computing units. The processor 1501 may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuits, and / or any device that manipulates signals based on operating instructions. In addition to other capabilities, the processor 1501 is configured to obtain and execute computer-readable instructions and data stored in a memory. The processor 1501 may include one or more processors. At this point, one or more processors 1501 may be a general-purpose processor (such as a central processing unit (CPU), an application processor (AP), etc.), a graphics processing unit (such as a graphics processing unit (GPU)), a visual processing unit (VPU), and / or an AI-specific processor (such as a neural processing unit (NPU)). One or more processors 1501 may control the processing of input data according to predefined operating rules or artificial intelligence (AI) models stored in non-volatile memory and volatile memory (i.e., memory 1505). Predefined operating rules or artificial intelligence models are provided by training or learning. The processor 1501 may control operations of other elements of the UE 301 and the overall operation of the UE 301. Therefore, the operation of the UE 301 may be understood to be substantially performed by the processor 1501.

[0237] Memory 1505 may include any non-transitory computer-readable medium known in the art, including, for example, volatile memory (such as static random access memory (SRAM) and dynamic random access memory (DRAM)) and / or non-volatile memory (such as read-only memory (ROM), erasable programmable ROM, flash memory, hard disks, optical disks, and tapes).

[0238] The methods disclosed herein provide various technical advantages and benefits including, for example, but not limited to, triggering measurements and moving to a stable beam if the current beam has many outages even if the current beam is strong.

[0239] The disclosed method also provides flexibility in measurement reporting. In situations where UE mobility is high, the disclosed method facilitates handover of the UE, for example but not limited to, without requiring the UE to perform measurements and reporting.

[0240] In mmWave and 6G terahertz systems, UEs are very sensitive to orientation. The disclosed method helps trigger re-evaluation of UE measurement metrics, for example but not limited to, and reports to the network if any orientation change associated with the UE is detected.

[0241] In addition, the disclosed method advantageously provides (for example but not limited to) the flexibility of having separate UL and DL TRPs, so that the overall performance is more balanced. Therefore, the disclosed method helps (for example but not limited to) overcome the problem of UL and DL channel imbalance.

[0242] Furthermore, the disclosed method provides, for example but not limited to, an innovative framework for performing measurements in a multi-TRP system and is therefore able to solve foreseeable problems within a multi-TRP system.

[0243] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs.The systems, methods, and examples provided herein are illustrative only and are not intended to be limiting.

[0244] Although specific language has been used to describe this subject, any limitation arising therefrom is not intended. It is apparent to those skilled in the art that various work modifications may be made to the method to implement the concepts disclosed herein. The accompanying drawings and the foregoing description provide examples of embodiments. It will be appreciated by those skilled in the art that one or more of the elements described may be well combined into a single functional element. Alternatively, some elements may be divided into multiple functional elements. Elements from one embodiment may be added to another embodiment.

[0245] The embodiments disclosed herein may be implemented using at least one hardware device and performing a network management function to control elements.

[0246] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can easily modify and / or adapt these specific embodiments for various applications by applying current knowledge without departing from the general concepts, and therefore, these adaptations and modifications should and are intended to be understood to be within the meaning and scope of equivalents of the disclosed embodiments. It should be understood that the wording or terminology employed herein is for descriptive and not limiting purposes. Therefore, although the embodiments herein have been described according to preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced by modification within the scope of the embodiments as described herein.

Claims

1. A method for selecting a measurement mode by a user equipment UE (301) in a communication system comprising a plurality of transmission and reception points TRP, the method comprising: Receiving (401) from a network entity (303) system information indicating one or more measurement modes supported by the network entity (303); selecting (405) a measurement mode among the one or more measurement modes based on one or more UE parameters; sending (407) a Radio Resource Control, RRC, connection request for the selected measurement mode to the network entity (303); as well as In response to the sent RRC connection request, a first RRC connection configuration for configuring the UE (301) in the selected measurement mode is received (409) from the network entity (303).

2. The method according to claim 1, further comprising: sending (413) UE assistance information to the network entity (303) indicating a request to change a selected measurement mode when in an RRC connected state; as well as In response to the sent UE assistance information, a second RRC connection configuration for reconfiguring the UE with the changed measurement mode is received (415) from the network entity (303).

3. The method according to claim 1, wherein The one or more UE parameters include at least one of: a mobility parameter associated with the UE, a rotation parameter associated with the UE, a power level associated with the UE, a thermal level associated with the UE, and a cluster configuration associated with the UE, and The information corresponding to the UE cluster configuration indicates whether the UE is configured with a cluster of TRP.

4. The method according to claim 1, wherein: Selecting the measurement mode among the one or more measurement modes comprises: Selecting a third measurement mode as the measurement mode among the one or more measurement modes is based on one of the following: Determining that the UE power level is less than a threshold power level; determining that the UE thermal level is greater than a threshold thermal level; or It is determined that the UE is not cluster configured and that the UE mobility is greater than a threshold mobility value.

5. The method according to claim 4, wherein: In the third measurement mode, the method further comprises: receiving (319) a measurement configuration from the network entity (303); sending (321) UE location information and an uplink sounding reference signal (ULSRS) of the UE to the network entity (303); and In response to the transmitted location information and the UL SRS, a mobility command is received (323) from the network entity (303) to switch to a new TRP selected by the network entity (303), wherein the selection of the new TRP is based on the UE location information and the UL SRS.

6. The method according to claim 5, wherein: In the third measurement mode, the method further comprises: receiving information from the network entity (303) related to triggering an event associated with a reporting criterion, wherein The information related to the triggering event includes information associated with the triggering first event, and When the uplink channel quality of the UE becomes less than a threshold channel quality, triggering the first event; When the uplink channel quality becomes less than the threshold channel quality, reporting the triggered first event to the network entity (303); and When reporting the triggered first event to the network entity, the UE location information and the UL SRS are sent to the network entity (303).

7. The method according to claim 1, wherein: Selecting the measurement mode among the one or more measurement modes comprises: The second measurement mode is selected as the measurement mode among the one or more measurement modes based on: determining one of the UE power level being greater than a threshold power level or the UE thermal level being less than a threshold thermal level, and Determine that the UE is cluster-configured with the cluster of the TRP.

8. The method according to claim 7, wherein: In the second measurement mode, the method further comprises: receiving (313) measurement configuration and cluster information associated with the plurality of TRPs from the network entity; determining and selecting a new TRP among the plurality of TRPs based on the received measurement configuration and the cluster information; and A signal is sent to the network entity notifying the switching of the downlink DL path to the new TRP.

9. The method according to claim 8, wherein: In the second measurement mode, the method further comprises: receiving information from the network entity related to triggering an event associated with a reporting criterion, wherein The information related to the triggering of the event includes information associated with the triggering of the first event and the second event, When the new TRP resource becomes better than the threshold, the first event is triggered, and When the new TRP resource becomes better than the configured TRP resource offset, triggering the second event; reporting the triggered first event and the triggered second event to the network entity, and When the triggered first event and the triggered second event are reported to the network entity, a signal is sent to the network entity, the signal notifying the switching of the downlink DL path to the new TRP.

10. The method according to claim 1, wherein: Selecting the measurement mode among the one or more measurement modes comprises: The hybrid mode is selected as the measurement mode among the one or more measurement modes based on: determining one of the UE power level being greater than a threshold power level or the UE thermal level being less than a threshold thermal level, determining that the UE mobility is less than a threshold mobility value, and It is determined that it is necessary to move the UE in the hybrid mode.

11. The method according to claim 10, wherein: The UE is determined to move in the hybrid mode based on the UE determining that a first TRP is better suited for the downlink DL and a second TRP different from the first TRP is better suited for the uplink UL.

12. The method according to claim 4, wherein: Selecting the measurement mode among the one or more measurement modes comprises: Based on unavailability of other measurement modes except the first measurement mode among the one or more measurement modes, the first measurement mode among the one or more measurement modes is selected as the measurement mode.

13. The method according to claim 12, wherein: In the first measurement mode, the method further comprises: receiving (305) a measurement configuration from the network entity (303); performing (307) measurements based on the received measurement configuration; sending (309) a measurement report of the measurements performed to the network entity (303); and In response to the sent measurement report, a mobility command is received (311) from the network entity (303) to switch to a new TRP, wherein the new TRP is selected based on the measurement report.

14. The method according to claim 13, wherein: In the first measurement mode, the method further comprises: receiving information from the network entity related to triggering an event associated with a reporting criterion, wherein The information related to the triggering event includes information associated with the triggering of the first event and the second event, When the interruption of the signal quality becomes worse than a threshold, triggering the first event, and When the signal quality becomes worse than a threshold due to a change in the direction of the UE, triggering the second event; reporting the triggered first event and the triggered second event to the network entity; and Perform one of the following operations: when reporting the triggered first event and the triggered second event, send the signal notifying the switching of the downlink DL path to the new TRP, or when reporting the triggered first event and the triggered second event, receive the mobility command for switching to the new TRP from the network entity.

15. A user equipment UE (301), comprising: Transceiver (1503); as well as At least one processor (1501) coupled to the transceiver (1503), wherein the at least one processor is configured to operate according to the method of any one of claims 1 to 14.

Images