Method for Doppler Information Reporting - Patent application

Abstract

The apparatus comprises means for receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; means for performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; means for determining whether the at least one validity condition associated with the at least one measurement is valid; and means for reporting the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network.

Description

[Technical Field]

[0001] Examples and non-limiting illustrative embodiments relate generally to communications, and more particularly to methods for Doppler information reporting. [Background technology]

[0002] It is known to perform Doppler measurements in wireless communication networks. Summary of the Invention [Means for solving the problem]

[0003] According to one aspect, an apparatus comprises means for receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; means for performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; means for determining whether the at least one validity condition associated with the at least one measurement is valid; and means for reporting the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network.

[0004] According to one aspect, an apparatus comprises: means for transmitting a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; means for receiving from the user equipment a report including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and means for transmitting, using a backhaul link, to at least one transmission / reception point the at least one measurement and the determination of whether the at least one validity condition is valid.

[0005] According to one aspect, a method includes receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; determining whether the at least one validity condition associated with the at least one measurement is valid; and reporting the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network.

[0006] According to one aspect, a method includes transmitting a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; receiving a report from the user equipment including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and transmitting the at least one measurement and the determination of whether the at least one validity condition is valid to at least one transmission / reception point using a backhaul link.

[0007] According to one aspect, an apparatus comprises at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to cause, using the at least one processor, the apparatus to at least: receive a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; use the configuration to perform at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal; determine whether the at least one validity condition associated with the at least one measurement is valid; and report the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network.

[0008] According to one aspect, an apparatus comprises at least one processor and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured, using the at least one processor, to cause the apparatus to at least: transmit a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; receive a report from the user equipment including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and transmit, to at least one transmission / reception point, using a backhaul link, the at least one measurement and the determination of whether the at least one validity condition is valid.

[0009] According to one aspect, a machine-readable non-transitory program storage device is provided that tangibly embodies a program of instructions executable by the machine to perform operations including receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; determining whether the at least one validity condition associated with the at least one measurement is valid; and reporting the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network.

[0010] According to one aspect, a machine-readable non-transitory program storage device is provided that tangibly embodies a program of instructions executable by a machine to perform operations including: transmitting a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; receiving a report from the user equipment including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and transmitting the at least one measurement and the determination of whether the at least one validity condition is valid to at least one transmission / reception point using a backhaul link.

[0011] The foregoing aspects and other features are explained in the following description, taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a block diagram of an example, non-limiting system in which illustrative embodiments may be implemented. [Figure 2] FIG. 1 is a diagram illustrating an example of an OFDM DL TRS in NR Rel-15. [Figure 3] FIG. 10 illustrates the use of NZP CSI-RS symbols to measure Doppler information at a UE. [Figure 4] FIG. 1 illustrates Doppler estimation based on UL SRS. [Figure 5] FIG. 1 illustrates signaling for a UE-based Doppler estimation and correction method according to an example described herein. [Figure 6] FIG. 1 is a diagram of an exemplary device configured to implement the examples described herein. [Figure 7] FIG. 1 is a diagram showing a specific example of an example of a non-volatile memory medium. [Figure 8]1 is a flowchart of a method for carrying out examples described herein. [Figure 9] 1 is a flowchart of a method for carrying out examples described herein. DETAILED DESCRIPTION OF THE INVENTION

[0013] Referring to FIG. 1, this figure illustrates a block diagram of one possible, non-limiting example in which the examples may be practiced. Shown is a user equipment (UE) 110, a radio access network (RAN) node 170, and a network element 190. In the example of FIG. 1, the user equipment (UE) 110 is in wireless communication with a wireless network 100. The UE is a wireless device that can access the wireless network 100. The UE 110 includes one or more processors 120, one or more memories 125, and one or more transceivers 130 interconnected through one or more buses 127. Each of the one or more transceivers 130 includes a receiver Rx 132 and a transmitter Tx 133. The one or more buses 127 may be an address bus, a data bus, or a control bus, and may include any interconnection mechanism, such as a series of wires on a motherboard or integrated circuit, optical fiber, or other optical communication equipment. The one or more transceivers 130 are connected to one or more antennas 128. The one or more memories 125 include computer program code 123. The UE 110 includes a module 140 including one or both of components 140-1 and / or 140-2, which may be implemented in many manners. The module 140 may be implemented in hardware as module 140-1, such as implemented as part of one or more processors 120. The module 140-1 may also be implemented as an integrated circuit or via other hardware such as a programmable gate array. In another example, the module 140 may be implemented as module 140-2, which is implemented as computer program code 123 and executed by one or more processors 120. For example, the one or more memories 125 and the computer program code 123 may be configured to cause the user equipment 110, using the one or more processors 120, to perform one or more of the operations described herein. The UE 110 communicates with the RAN node 170 via a wireless link 111.

[0014] The RAN node 170 in this example is a base station that enables wireless devices, such as the UE 110, to access the wireless network 100. The RAN node 170 may be, for example, a base station for 5G, also known as New Radio (NR). In 5G, the RAN node 170 may be an NG-RAN node, which is defined as either a gNB or an ng-eNB. A gNB is a node that provides NR user plane and control plane protocol terminations for UEs and connects to the 5GC (e.g., network element 190) via an NG interface (e.g., connection 131). A ng-gNB is a node that provides E-UTRA user plane and control plane protocol terminations for UEs and connects to the 5GC via an NG interface (e.g., connection 131). An NG-RAN node may include multiple gNBs, which may also include a central unit (CU) (gNB-CU) 196 and a distributed unit (DU) (gNB-DU), of which DU 195 is shown. It should be noted that the DU 195 may include a radio unit (RU) or may be coupled to and control a radio unit. The gNB-CU 196 is a logical node that hosts the radio resource control (RRC), SDAP and PDCP protocols of the gNB, or the RRC or PDCP protocols of the en-gNB, which controls the operation of one or more gNB-DUs. The gNB-CU 196 terminates the F1 interface connected to the gNB-DU 195. The F1 interface is indicated as reference numeral 198, which also indicates a link between a remote element of the RAN node 170 and a centralized element of the RAN node 170, such as between the gNB-CU 196 and the gNB-DU 195. The gNB-DU 195 is a logical node that hosts the RLC, MAC, and PHY layers of the gNB or en-gNB, and its operation is partially controlled by the gNB-CU 196. One gNB-CU 196 supports one or more cells. One cell may be supported by one gNB-DU 195, or one cell may be supported / shared by multiple DUs under RAN sharing.The gNB-DU 195 terminates an F1 interface 198 connected to the gNB-CU 196. It should be noted that although the DU 195 is considered to include the transceiver 160, e.g., as part of an RU, in some instances of this may have the transceiver 160 as part of a separate RU, e.g., under the control of and connected to the DU 195. The RAN node 170 may also be an eNB (Evolved NodeB) base station for LTE (Long Term Evolution), or any other suitable base station, access point, access node, or node.

[0015] The RAN node 170 includes one or more processors 152, one or more memories 155, one or more network interfaces (N / WI / F) 161, and one or more transceivers 160, interconnected through one or more buses 157. Each of the one or more transceivers 160 includes a receiver Rx 162 and a transmitter Tx 163. The one or more transceivers 160 are connected to one or more antennas 158. The one or more memories 155 include computer program code 153. The CU 196 may include a processor 152, a memory 155, and a network interface 161. It should be noted that the DU 195 may itself also include a memory / memories and processors, and / or other hardware, which are not shown.

[0016] The RAN node 170 includes a module 150 including one or both of components 150-1 and / or 150-2, which may be implemented in many ways. The module 150 may be implemented in hardware as module 150-1, such as implemented as part of one or more processors 152. The module 150-1 may also be implemented as an integrated circuit or via other hardware such as a programmable gate array. In another example, the module 150 may be implemented as module 150-2, which is implemented as computer program code 153 and executed by one or more processors 152. For example, the one or more memories 155 and the computer program code 153 are configured to cause the RAN node 170 to perform one or more of the operations described herein using the one or more processors 152. It should be noted that the functionality of the module 150 may be distributed, such as distributed between the DU 195 and the CU 196, or may be implemented solely in the DU 195.

[0017] One or more network interfaces 161 communicate over a network, such as via links 176 and 131. Two or more gNBs 170 may communicate, for example, using link 176. Link 176 may be wired or wireless, or both, and may implement, for example, an Xn interface for 5G, an X2 interface for LTE, or other suitable interfaces for other standards.

[0018] 1, RAN node 170 may communicate with RAN node 170-2, RAN node 170-3, and RAN node 170-N using link 176. UE 110 communicates with RAN node 170-2 via wireless link 111-2, UE 110 communicates with RAN node 170-3 via wireless link 111-3, and UE 110 communicates with RAN node 170-N via wireless link 111-N. RAN node 170-2 includes TRP61 and TRP62, RAN node 170-3 includes TRP71 and TRP72, and RAN node 170-N includes TRP81 and TRP82. Each of RAN nodes 170, 170-2, 170-3, and 170-N may include more than two TRPs.

[0019] The one or more buses 157 may be an address bus, a data bus, or a control bus, and may include any interconnection mechanism, such as a set of wires on a motherboard or integrated circuit, optical fiber or other optical communication equipment, a wireless channel, etc. For example, the one or more transceivers 160 may be implemented as a remote radio head (RRH) 195 for LTE or a distributed unit (DU) 195 for a gNB implementation for 5G, where other elements of the RAN node 170 are perhaps in a different physical location than the RRH / DU 195, and the one or more buses 157 may be implemented in part, for example, as optical fiber cables or other suitable network connections for connecting other elements of the RAN node 170 (e.g., a central unit (CU), gNB-CU 196) to the RRH / DU 195. Reference numeral 198 also indicates those suitable network links.

[0020] A RAN node / gNB may include one or more TRPs to which the methods described herein may be applied. Figure 1 shows that RAN node 170 includes two TRPs, TRP51 and TRP52. RAN node 170 may host or include other TRPs not shown in Figure 1. TRP51 and TRP52 may form part of the transceiver 160 components.

[0021] Within the scope of the present disclosure, two TRPs may be for one gNB (e.g., a serving cell) and two other TRPs may be for another cell / gNB (a different PCI from the serving cell). Alternatively, all TRPs may be associated with the same cell. Thus, the TRPs described herein may be associated with the same or different PCIs.

[0022] Relay nodes in NR are called integrated access backhaul nodes. The mobile termination part of the IAB node facilitates the backhaul (parent link) connection. The mobile termination part is a function that has UE functionality. The distributed unit part of the IAB node facilitates the so-called access link (child link) connection (i.e., access link UE in case of multi-hop IAB and backhaul to other IAB nodes). The distributed unit part is responsible for specific base station functions. IAB scenarios may follow a separated architecture, where a central unit hosts higher layer protocols in the UE and terminates the control plane and user plane interface to the 5G core network.

[0023] It should be noted that while the description herein refers to a "cell" performing a function, it should be clear that the equipment forming the cell may perform the function. A cell constitutes part of a base station. That is, there may be multiple cells per base station. For example, there may be three cells for a single carrier frequency and associated bandwidth, with each cell covering one-third of a 360-degree area, such that the coverage area of a single base station covers approximately an ellipse or circle. Furthermore, each cell may correspond to a single carrier, or the base station may use multiple carriers. Thus, if there are three 120-degree cells and two carriers per carrier, the base station has a total of six cells.

[0024] The wireless network 100 may include one or more network elements 190, which may include core network functions that provide connectivity to additional networks, such as telephone networks and / or data communication networks (e.g., the Internet), via one or more links 181. Such core network functions for 5G may include a Location Management Function (LMF), an Access and Mobility Management Function (AMF), a User Plane Function (UPF), and / or a Session Management Function (SMF). Such core network functions for LTE may include an MME (Mobility Management Entity) / SGW (Serving Gateway) function. Such core network functions may include a Self-Organizing / Optimizing Network (SON) function. These are merely example functions that may be supported by the network element 190; both 5G and LTE functions may be supported. The RAN node 170 is coupled to the network element 190 via a link 131. The link 131 may be implemented, for example, as an NG interface for 5G or an S1 interface for LTE, or other appropriate interface for other standards. Network element 190 includes one or more processors 175, one or more memories 171, and one or more network interfaces (N / WI / F) 180 interconnected via one or more buses 185. The one or more memories 171 include computer program code 173. Computer program code 173 may include SON and / or MRO functions 172.

[0025] One or more network elements 190 include a module 177 that may include near real-time RIC functionality. Computer program code 173 may include near real-time RIC functionality. Module 150-1 and / or module 150-2 may include near real-time RIC functionality.

[0026] Wireless network 100 may implement network virtualization, which is the process of combining hardware and software network resources and network functions into a single software-based management entity: a virtual network. Network virtualization involves platform virtualization, often combined with resource virtualization. Network virtualization is categorized as either external, which combines many networks or portions of networks into virtual units, or internal, which provides network-like functionality to software containers on a single system. It should be noted that the virtualized entities resulting from network virtualization are still implemented, at some level, using hardware, such as processor 152 or processor 175 and memory 155 and memory 171, and that it is such virtualized entities that produce technical effects.

[0027] The computer-readable memories 125, 155, and 171 may be of any type suitable for the local technology environment and 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, non-transitory memory, transient memory, fixed memory, and removable memory. The computer-readable memories 125, 155, and 171 may be means for performing storage functions. The processors 120, 152, and 175 may be of any type suitable for the local technology environment and may include, by way of non-limiting example, one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. The processors 120, 152, and 175 may be means for performing functions such as controlling the UE 110, the RAN node 170, the network element 190, and other functions described herein. In general, various exemplary embodiments of user equipment 110 may include, but are not limited to, a cellular phone such as a smartphone, a tablet, a personal digital assistant (PDA) with wireless communication capabilities, a portable computer with wireless communication capabilities, an image capture device such as a digital camera with wireless communication capabilities, a gaming device with wireless communication capabilities, a music storage and playback appliance with wireless communication capabilities, an Internet appliance enabling wireless Internet access and browsing, a tablet with wireless communication capabilities, a head-mounted display such as one implementing virtual reality / augmented reality / mixed reality, and a portable unit or terminal incorporating a combination of such capabilities. UE 110 may also be a vehicle such as an automobile, or a UE mounted on a vehicle, a UAV such as a drone, or a UE mounted on a UAV.

[0028] The UE 110, the RAN node 170, and / or the network element 190 (and associated memory, computer program code, and modules) may be configured to implement (e.g., portions of) the methods described herein, including methods for Doppler information reporting. Thus, the computer program code 123, the module 140-1, the module 140-2, and other elements / features shown in FIG. 1 of the UE 110 may implement user equipment-related aspects of the methods described herein. The computer program code 153, the module 150-1, the module 150-2, and other elements / features shown in FIG. 1 of the RAN node 170 may implement gNB / TRP-related aspects of the methods described herein. The computer program code 173 and other elements / features shown in FIG. 1 of the network element 190 may be configured to implement network element-related aspects of the methods described herein.

[0029] Having introduced a suitable but non-limiting technical context for the practice of exemplary embodiments, the exemplary embodiments will now be described in more detail. The examples described herein relate to PHY layer extensions that enable Doppler shift / spread / measurements that take into account a MIMO-related environment. Specific components are implemented by the UE and gNB. The methods described herein relate to HST-SFN extensions to Release 17 (e.g., R1-2101450 and R1-2202320) for UE-based Doppler measurement reporting (particularly, explicit approaches). See also RP-213517, RP-213598, and R1-2204143. The examples described herein relate to validity conditions for Doppler parameter measurements, including default and fallback reporting modes. In particular, TRP-specific and inter-TRP Doppler parameter measurement validity conditions (e.g., power thresholds or offsets) and corresponding reporting are described herein. The examples described herein provide additional accuracy and reliability.

[0030] While the standardization for Release 18 focuses on uplink (UL) MIMO enhancements, necessary enhancements to downlink (DL) MIMO that facilitate the use of large antenna arrays (not only for FR1 but also for FR2) still need to be introduced to meet the demands for enhanced NR deployments [Tdoc No. RP-213517 - "New WID: MIMO Evolution for Downlink and Uplink"].

[0031] MIMO in Release 16 / 17 provides support for multi-TRP deployments in the form of non-coherent joint transmission (NC-JT). Furthermore, coherent joint transmission (CJT), introduced in LTE Release 11, can improve coverage and average throughput in commercial deployments with high-performance backhaul and synchronization capabilities. In light of this, enhancements to CSI acquisition for FDD and TDD targeting FR1 could be beneficial in extending the use of CJT to NR multi-TRP deployments [Tdoc No. RP-213517 - "New WID: MIMO Evolution for Downlink and Uplink"]. Therefore, CJT is considered as one of the potential technologies for 5G evolved cellular systems targeting Release 18. With CJT, multiple TRPs serve each UE in a coherent manner, enabling significant improvements in cell-edge UE throughput. However, CJT requires accurate channel state information (CSI), e.g., phase, timing, and frequency synchronization, for successful operation. For example, phase changes in the CSI may result in poor combining at the target UE, resulting in a reduced SINR (and therefore reduced throughput) for the UE.

[0032] Considering a moving UE, the effect of Doppler shift / spread is one of the reasons why the phase variations on channels from multiple TRPs are different. The UE's speed is different for each of the multiple TRPs, and therefore the channel from each TRP to the UE is affected by the resulting Doppler shift / spread. In the case of CJT-CoMP (Coordinated Multipoint), this causes interference at the UE, resulting in reduced throughput.

[0033] NR Release 15 supports coarse downlink time and frequency synchronization based on secondary and primary synchronization signals located within synchronization signal blocks (SSBs). After receiving the SSBs, the UE is intended to use time and frequency tracking reference signals (TRSs) to compensate for residual time and frequency error offsets and to adjust the parameters of the DMRS channel estimator, i.e., the Wiener filter length in time and frequency, to match the coherence time and frequency of the wireless channel.

[0034] As mentioned above, NR Release 15 provides a mechanism to support downlink TRS transmission by using NZP-CSI-RS resources with a CP-OFDM waveform [TS38.211]. TS38.214 supports two different NZP-CSI-RS resource set configurations for a UE to perform time and frequency tracking. More specifically, according to [TS38.214], for an NZP-CSI-RS-ResourceSet configured in the higher layer parameter trs-Info, the UE shall assume that antenna ports with the same port index as the configured NZP CSI-RS resources in the NZP-CSI-RS-ResourceSet are identical.

[0035] In frequency range 1 (i.e., below 6 GHz), a UE may be configured with one or more NZP CSI-RS sets, where an NZP-CSI-RS-ResourceSet consists of four periodic NZP CSI-RS resources in two consecutive slots with two periodic NZP-CSI-RS resources in each slot.

[0036] In frequency range 2 (i.e., above 6 GHz), a UE may be configured with one or more NZP CSI-RS sets, where an NZP-CSI-RS-ResourceSet consists of two periodic CSI-RS resources in one slot, or an NZP-CSI-RS-ResourceSet of four periodic NZP CSI-RS resources in two consecutive slots with two periodic NZP-CSI-RS resources in each slot.

[0037] The UE expects that the periodic CSI-RS resource set and the aperiodic CSI-RS resource set consist of the same number of CSI-RS resources and the same number of CSI-RS resources in a slot. If an aperiodic CSI-RS resource set is triggered, and if the associated periodic CSI-RS resource set consists of four periodic CSI-RS resources with two consecutive slots with two periodic CSI-RS resources in each slot, the upper layer parameter aperiodic triggering offset indicates the triggering offset of the first slot of the first two CSI-RS resources in the set.

[0038] Figure 2 shows an example of CP-OFDM-based DL NZP-CSI-RS-based TRS transmission in NR Release 15. As shown, the NZP CSI-RS resource is single-port with density 3. The maximum bandwidth of the CSI-RS resource is 52 physical resource blocks (PRBs). The time-domain location of two CSI-RS resources in a slot, or four CSI-RS resources in two consecutive slots, is given by one of the following [TS38.214]: {4,8}, {5,9}, or {6,10} for frequency range 1 and FR2, {0,4}, {1,5}, {2,6}, {3,7}, {7,11}, {8,12}, or {9,13} for FR2.

[0039] As shown in Figure 2, the first NZP-CSI-RS 202 and the second NZP-CSI-RS 204 are within the PDSCH 206. The M-IDFT 208 is applied to the PDSCH 206. The CP 210 is applied to the output of the M-IDFT 208. The system BW 212 is affected by the processes and configuration shown in Figure 2.

[0040] The Release 17 NR specifications provide support for both network-based and Release 15 UE-based Doppler shift / spread tracking, as previously mentioned. In the network-based approach, DL PDSCH is used in high-speed train (HST) scenarios, where it is transmitted in a single frequency network (SFN) manner from multiple TRPs after Doppler compensation based on uplink measurements. Further details are described herein.

[0041] NR Release 18 is intended to specify CSI reporting enhancements for high / medium UE speeds by specifying time-domain correlation / Doppler-domain information to support DL precoding (targeting FR1) [Tdoc No. RP-213517 - "New WID: MIMO Evolution for Downlink and Uplink"] as follows: - Improvements to Release 16 / 17 Type II codebooks without modifications to the spatial and frequency domain bases - UE reporting of time domain channel properties measured via CSI-RS for tracking purposes.

[0042] Based on the proposal in [Tdoc No. R1-2203151 - "New WID: CSI enhancement for coherent JT and mobility"], the UE may measure Doppler information from a set of uniformly separated NZP CSI-RS bursts as shown in Figure 3. The NZP CSI-RS bursts help the UE to estimate Doppler information with more accuracy and reliability.

[0043] CSI-RS resource sets (302, 304, 306) for P / SP CSI-RS 310 and CSI-RS resource set 308 for AP CSI-RS 320 are shown in FIG. 3, where each of the CSI-RS resource sets (302, 304, 306, 308) includes uniformly separated NZP CSI-RS bursts, and at least for CSI-RS resource sets 302 and 308, the NZP CSI-RS bursts are separated by 1d time slots for a given time interval d.

[0044] The extracted Doppler information from the UE can be used at the gNB to improve downlink throughput, for the following use case [Tdoc No. R1-2203229 - "New WID: On CSI enhancements for Rel-18 NR MIMO evolution"]: Using the UE reports, the network may determine the configuration periodicity or time of triggering of CSI-RS, CSI reports or SRS. Using the UE report, the network decides whether to configure Type I or Type II CSI reports. Using the UE report, the network may decide whether to use reciprocity-based CSI acquisition or Type II-based CSI feedback for MU-MIMO scheduling. Using the UE report, the network may determine the number of additional DMRS symbols required. The network uses the reports as input to the open-loop link adaptation algorithm to refine the selection of a robust MCS, even for the URLLC case. The network uses the reports as input to AI / ML algorithms at higher layers of the network or for beam management.

[0045] To achieve the benefits of coherent joint transmission with precoding for TDD-based DL multi-TRP operation in NR Release 18 and beyond (i.e., inter-cell and MU-MIMO interference mitigation and improved spectral efficiency), accurate DL CSI information plays a key role in this process. Due to UE mobility, obtaining up-to-date DL CSI information via DL CSI reporting based on UL SRS sounding or DL RS measurements can be challenging. In practice, there is always a time delay between the time of UL / DL CSI measurement (and estimation) and the time when joint precoding between different TRPs should be applied. There are also several other potential causes of CSI inaccuracy, such as estimation errors, latency associated with backhauling, and quantization of reported CSI information. To address some of the impacts, network-side time-domain prediction of CSI information based on UE Doppler information measurement and reporting may be seen as an attractive candidate for DL multi-TRP CJT in Release 18 and beyond.

[0046] The problem of wireless channel time evolution tracking was addressed in the High Speed Train (HST) scenario. In the HST scenario, a dominant LoS propagation path always exists, and only the Doppler shift needs to be tracked for each TX-RX pair between the TRP and the UE. As mentioned above, Release 17 provides support for both UE-based and network-based approaches for SFN HST scenarios, including the network utilizing UL SRS transmission with Doppler shift pre-compensation on the network side. The primary focus of the examples described herein is on the network-based approach.

[0047] The problem with the Rel-17 network-based approach is that Doppler estimation at each TRP requires multiple UL SRS transmissions from a single UE. As a result, the UL SRS resource overhead increases significantly, causing a decrease in UL PUSCH throughput. Furthermore, due to limited UL TX power, the quality of Doppler information estimation based on UL SRS transmissions may degrade significantly in some scenarios, for example, when the UE is located at the edge of the serving coverage of the TRP.

[0048] To enhance the network-based pre-compensation approach by reducing UL SRS overhead and latency, to improve measurement reliability, and to increase network efficiency, new methods for Doppler information measurement and reporting based on DL TRS measurements need to be developed.

[0049] Figure 4 shows Doppler estimation based on UL SRS. Figure 4 is based in part on Tdoc No. RP-2123517 - "New WID: MIMO Evolution for Downlink and Uplink."

[0050] Doppler estimation for HST scenarios is described in [Tdoc No. R1-2101450 - "Enhancements on HST-SFN deployment" R4], where Doppler shift can be estimated using UL SRS. This is shown in FIG. 4 for the case of two TRPs (401, 402). First, TRS1 404 and TRS2 406 are transmitted from TRP1 401 and TRP2 402, respectively. Then, UE 110 measures "fD1" associated with TRS1 404 and compensates for it in the UL. At this stage, UE 110 transmits UL SRS (408, 410) at "Fc + fUE," which is received by TRP1 401 at "Fc + fUE + fD1" and by TRP2 402 at "Fc + fUE + fD2." The difference in Doppler shift between TRP1 401 and TRP2 402 can be calculated using backhaul signaling and pre-compensated while transmitting data.

[0051] However, in some scenarios, the UL SRS transmission 408 directed to TRP1 401 may be subject to the UE 110's limited UL TX power budget, resulting in larger estimation errors, e.g., related to Doppler shift, CSI, etc. From this perspective, the number of different SRS transmissions associated with different TRPs needs to be increased as described in [Tdoc No. R1-2202320 - "Maintenance of Enhancements for HST-SFN deployment"]. For example, to estimate small Doppler shifts, UL SRS transmission opportunities need to be configured over several symbols / slots. It should be noted that the radio coherence time is roughly inversely proportional to the Doppler spread / shift. This can induce potential scheduling limitations, leading to extra latency and UL reference signal resource overhead, as well as reduced UL data throughput. In [Tdoc No. R1-2101450 - "Enhancements on HST-SFN deployment"] an alternative approach is defined in which the Doppler parameters are determined on the UE side by performing measurements on TRS reference signal transmissions and reporting them to the network.

[0052] Accordingly, validity conditions for Doppler parameter measurements and corresponding reporting are described herein. Additionally, methods for both default and fallback Doppler information reporting modes are described herein.

[0053] The suitability of the UE reporting mechanism for Doppler estimation and Doppler parameters (enhanced CSI parameters) at the UE is summarized as follows:

[0054] The following assumptions are made: The network may configure one or more TRS resource sets via higher layer signaling (i.e., RRC) to act as "anchor" resources (used in Doppler difference calculations); The network may configure K TRS resource sets associated with each TRP-specific TRS resource via higher layer signaling. TRP# The network may configure the UE to measure the K strongest / dominant multipath components associated with each TRP-specific TRS resource. TRP# The network may provide the UE with decision parameters (such as a received power threshold level, a measurement time window, aging information, a reporting time offset, a maximum delay spread of a TRP-specific link, and a maximum propagation delay or delay spread of each TRS) to verify the strongest / dominant multipath components. The network may configure different standalone Doppler parameter / information reporting formats. In this context, standalone means that the report does not depend on other codebook-based CSI reporting. Alternatively, the network may configure a non-standalone Doppler parameter / information reporting format. The reporting format may include TRP-specific Doppler information (i.e., the difference between Doppler shift and / or plane Doppler shift, and / or the difference between phase and / or plane phase, and / or Doppler spread) and / or inter-TRP Doppler information. The network may configure a reporting format for the arrival time of the first multipath component associated with each configured TRS resource and each multipath component of the configured TRS resource. The network may configure a Doppler reporting time offset.

[0055] The main target of standalone or non-standalone Doppler information reporting is to assist the gNB, for example, in scheduling CSI-RS resources and CSI reporting periodicity, as well as in selecting the type of reporting (including selecting between mTRP CSI reporting and sTRP CSI reporting, such as Type-I NCJT and Type-II CJT). Furthermore, Doppler information reporting can be used to assist gNB-side prediction, for example, for DL precoding. This can be beneficial for both CSI feedback-based precoding schemes and UL SRS reciprocity-based precoding schemes. Both standalone and non-standalone Doppler information reporting can be used in the context of single-TRP and multi-TRP scenarios.

[0056] The validity and reporting of TRP-specific and inter-TRP Doppler information measurements (for one or more parameters) is defined as follows: Doppler information (e.g., an item of Doppler information) may be defined as either a multipath-specific Doppler shift or a multipath-specific Doppler shift difference between a resource (e.g., a TRS) associated with an "anchor" TRP and another TRP (sharing the same or a different Physical Cell ID (PCI)). The validity of Doppler parameter measurements may be defined, for example, based on one of the following conditions: Condition #1, TRP-specific or inter-TRP, K TRP# Based on the multipath power difference between dominant multipath components. Condition #2, based on the TRS resource application time for Doppler difference calculation, either TRP-specific or inter-TRP. Condition #3, based on the measurement time difference for Doppler difference calculation, either TRP-specific or inter-TRP. Condition #4, based on the arrival time calculation of each TRP-specific TRS. Or Condition #5, based on the reporting time offset.

[0057] Thus, a new method for Doppler information reporting is described that uses default and fallback reporting modes, where the default mode of operation is used when all or configured validity conditions are met, and the fallback mode of operation is used when at least one of the configured validity conditions is not met.

[0058] In the default operating mode (when all or configured validity conditions are met), the UE 110 uses the new CSI format to report parameters related to Doppler shift / spread and / or the number of one or more TRP-specific TRSs used for the measurement.

[0059] In a fallback operating mode (when at least one of the configured validity conditions is not met), the UE 110 reports at least one of a set of fallback parameters, such as a Doppler shift / spread value, an indication of a Doppler reporting format, an indication of an anchor resource set (if required), an indication of the number of valid paths to be measured, an indication of the number of valid TRS resources used for the measurement, an indication of aging validity for the measurement, the time difference between TRS resources, the arrival time difference of each multipath, and the anchor resource time difference with respect to the slot timing.

[0060] First, the network uses a downlink control signaling framework (e.g., via RRC and / or physical layer and / or MAC-level signaling, etc.) to configure the Doppler reference signal (e.g., TRS) or signal (e.g., SSB) resources and parameters to be measured (or verified) at the UE. Then, the TRP transmits the NZP-CSI-RS in the DL, and the UE performs the Doppler measurements requested by the network along with the validity of the measurements. Once the UE has completed the calculation of the Doppler parameters, the UE reports the Doppler information along with the configured validity conditions.

[0061] The network configures the UE with a predefined set of compliances for measuring Doppler parameters. For this purpose, it is assumed that the network configures the following parameters:

[0062] The network configures one or more TRS resource sets to act as "anchor" resources for calculating Doppler difference.

[0063] The network consists of K TRPs associated with each TRP-specific TRS resource being measured. TRP# The UE configures the K strongest / dominant multipath components for each of the TRP-specific TRS resources. TRP# Calculate and select the K strongest multipath components associated with each single antenna port TRS resource. TRP# To determine the strongest multipath components, a power threshold is defined, or a relative power difference to the first detected multipath component is defined. The default assumption is that an equal number of multipath components are used for each TRP-specific TRS resource.

[0064] The network configures the measurement time (or elapsed time) or the CSI / Doppler information associated with the measurement occasion. The aging information is configured by the network based on the channel conditions and the time at which the measurement is scheduled to be applied in DL relative to the measurement time. The network configures valid aging conditions for the UE, e.g., P consecutive TRS transmission occasions during which the UE performs measurements and also provides corresponding reports. By doing this, the network can impose measurement restrictions on the UE, forcing the UE to use specific TRS measurement occasions for specific reporting instances. As a result, the gNB can ensure that these measurements are actually related to a specific time window and not measurements accumulated over an undefined period. This can be useful, for example, when several periodic TRS resources are configured and then supplemented with aperiodic TRS resources. The delay spread of each TRP-specific TRS resource can be configured by the network. In that case, the UE is expected to receive all multipaths of the TRS within the delay spread. The maximum reporting time is configured by the network, within which the UE 110 must report Doppler information to the gNB 170. The maximum propagation delay of each TRP-specific TRS is set by the network, and the UE is expected to receive the TRS within the maximum propagation delay.

[0065] Introducing a validity condition for measurements can ensure the quality of Doppler parameter measurements and avoid ambiguity on the gNB side regarding how measurements are performed on the UE side. For example, condition #1, such as all of the configured K dominant multipath components being above a certain power threshold or power offset for the anchor TRS resource (to distinguish it from the thermal noise floor) at a certain level for network use (e.g., for network-side Doppler parameter prediction and indication to the UE), can ensure the quality of Doppler parameter measurements and avoid ambiguity on the gNB side regarding how measurements are performed on the UE side. Additionally, introducing condition #2 introduces a Doppler parameter measurement restriction on the UE such that the UE measures and calculates over P consecutive TRS transmission opportunities. Without this restriction, ambiguity remains for the network regarding which TRS resource the UE calculated the Doppler parameters from. A network, such as the RAN node 170 or the network element 190, can configure a Doppler (phase / frequency / time) parameter reporting format, e.g., a format for reporting one or more Doppler parameters. The TRP-specific Doppler parameters are calculated using the K TRP# The Doppler parameters between TRPs may include the actual Doppler shift values of the dominant paths or the relative (differentially coded) Doppler shift values specifically related to the dominant path TRP. The Doppler parameters between TRPs may include the K TRP#The TRP-specific time parameter may include the actual arrival time of one or more dominant path components of a TRS resource, and the time difference for a particular multipath may be calculated within the TRS and for each TRP-specific TRS resource. The TRP-specific time parameter may include the time difference between multipath components, which may be calculated based on the anchor TRP-specific TRS resource.

[0066] Upon receiving the Doppler configuration frame from the network (associated with the TRPs), the UE may appropriately perform Doppler measurements along with validity conditions for the received DL NZP-CSI-RS signals from each of the TRPs. The UE Doppler measurements and validity conditions are defined as follows:

[0067] The validity of TRP-specific and inter-TRP Doppler parameter measurement and reporting is defined (for one or more Doppler parameters) as follows:

[0068] The Doppler parameter may be defined as either a multipath-specific Doppler shift or a multipath-specific Doppler shift difference between resources associated with an "anchor" TRP and another TRP (sharing the same or a different physical cell ID (PCI)). In the case of a multipath scenario, the Doppler information may also be reported in the form of a Doppler spectrum. In this regard, the UE 110 calculates the Doppler spectrum at a given bandwidth and frequency resolution. The validity of the Doppler parameter measurement may be defined by using at least one of the following conditions (Conditions #1 to #5):

[0069] Condition #1, K TRP#Inter-TRP multipath power difference between the dominant multipaths: The UE calculates K TRP# Determine the dominant multipath components and order / rank them (in descending order) specifically for TRP. To define the validity of condition #1, TRP# All of the dominant multipath components must exceed a configured power threshold [dBm / dB], which may be set by the RAN node 170 or the network, such as with one or more network elements 190. In an alternative embodiment, the UE may configure the UE to transmit the signal at a power threshold (K UE ≦K TRP# ) UE (≧1) dominant components are allowed to be selected. Otherwise, the validity of condition #1 is not valid. In an alternative approach, to define the validity of condition #1, TRP# all of the dominant multipath components have a maximum D power-offset-max [dB] power offset. In an alternative embodiment, the UE may adjust the power offset to within the anchor's configured power threshold (K UE ≦K TRP# ) against D power-offset-max [dB] is the power offset, K UE (≧1) dominant components are allowed to be selected. Otherwise, the validity of condition #1 is not valid. When condition #1 is valid, the UE determines the Doppler shift associated with each path and the corresponding Doppler difference between the anchor resource and the reference resource associated with the TRP. Similarly, the coherent phase of each dominant path of the TRS or the coherent phase difference between the TRSs is calculated.

[0070] Condition #2, TRP-specific / inter-TRP TRS resource application time for Doppler difference calculation. The validity of condition #2 is ensured if the reception time difference between two different DL TRS resources is within the configured time offset D time-offset, for example, is defined when P consecutive TRS transmission opportunities are within a range of time t. When the validity between resources holds, the UE determines the corresponding Doppler parameters. Otherwise, the measurement is defined as invalid. One potential use case for this condition is when Doppler parameter measurements are performed between periodic / semi-persistent resources from different TRPs and / or between aperiodic resources from TRPs triggered by a single DCI or multiple DCIs.

[0071] Condition #3: TRP-specific / inter-TRP time difference calculation for verifying / reporting the estimated time (or elapsed time) of CSI information. Validity condition #3 is defined when aging information is configured. At least one of the TRS resources from all configured TRPs arrives within the aging time. In this case, UE 110 uses only one TRS resource from each TRP to calculate the Doppler shift / spread. Otherwise, this condition is not valid. If UE 110 receives multiple TRS resources associated with a single TRP within a predefined aging time, such as in the case of periodic TRS, the UE may use the multiple TRS resources from each TRP to more accurately estimate the Doppler parameters. The network may configure the aging time interval, for example, as a set of M periods of TRS transmission. Information measured after that time is considered no longer coherent. Validity condition #3 also relates to the maximum delay spread of the TRP-specific TRP. If UE 110 receives all multipaths within the delay spread (below a certain power threshold), the condition is valid; otherwise, the condition is not valid.

[0072] Condition #4: UE 110 checks the arrival time of one or more dominant paths of each TRP-specific TRS. If the dominant path of a TRP-specific TRS arrives after the maximum propagation delay or delay spread, the TRS is not valid. In some cases, longer propagation delays due to inter-symbol interference are not allowed.

[0073] Condition #5: The UE keeps track of the reporting time. This condition is not valid if the UE 110 is unable to send the report within the reporting time. This may be the case if the UE does not receive all TRSs or if the UE 110 does not have free resources to send the report on the uplink.

[0074] After completing the Doppler measurements, the UE uses the following reporting method to report the Doppler measurements along with the validity conditions to the network (associated with the TRP).

[0075] The method for Doppler information reporting using the default mode of operation is defined as follows:

[0076] Default operating mode and associated reporting format: (if all configured validity conditions are met). The CSI report includes one of the following options with corresponding elements: Option A: Non-differential reporting with L-bit quantized Doppler value and validity bit=1, Option B: Differential reporting with L-bit quantized Doppler difference value and validity bit=1. The report includes some of the TRP-specific TRS resources used for the measurement. Fallback operating mode and associated reporting format: (if at least one of the validity conditions is not met), includes Case 1 or Case 2.

[0077] Case 1: The UE 110 may report by adding a validity condition to each measurement. The Doppler shift or Doppler difference is reported. Whether the anchor TRS resource is valid or not may be reported. If the anchor node is selected differently, an indication of the anchor TRS resource may be reported. A validity bit for each path measurement may be reported. A validity bit for each measured Doppler difference may be reported. A validity bit for the application time may be reported. A validity bit for aging information may be reported. An indication of some of the TRP-specific TRS resources used for the measurement may be reported. Alternatively, to reduce reporting overhead, the report may include only one validity bit to indicate whether all measurements are valid. In an alternative approach, a bit vector of length Q (= number of measurements) is defined to indicate whether the measurement is valid (= 1) or not (= 0). In Case 1, a network, such as the RAN node 170 or one or more network elements 190, may derive the number of TRPs involved in the measurement from the validity bit.

[0078] Case 2: The UE 110 may report parameters by encoding validity information for the measurement. The validity of the Doppler difference or Doppler shift measurement may be reported. The number of measured valid paths may be reported. An indication of the number of TRP-specific TRS resources used for the measurement may be reported, which may be used for aging information while the network applies DL compensation. An indication of the number of TRPs involved in the measurement may be reported, which may be used only for these TRPs for CJT. An indication of validity for the application time may be reported.

[0079] In addition, UE 110 may also reuse existing beam management CSI reports by adding a validity bit or other bits for each measurement, or UE 110 may use the reporting methods described herein based on validity conditions.

[0080] If the configured validity conditions are not met on the UE side, a fallback behavior is defined. The fallback behavior may provide an indication of whether one or more measurements are valid (in case one or more measurements are not valid). This may be done by reserving some additional payload bits for the validity indication of each configured measurement (i.e., 0 = not valid or 1 = valid), or by determining some value (e.g., some maximum / minimum value) that implicitly indicates that a measurement is valid or invalid (allowing the use of a single reporting format for reporting valid and invalid measurements).

[0081] 5 shows an example / method 500 for Doppler information reporting for LoS cases. Assuming UE 110 is associated with TRP1 501, TRP1 501 first transmits a "Doppler Configuration" frame 510 to UE 110, which includes the network parameters and conditions to be measured. Then, each TRP (501, 502, 503) transmits a TRS using the allocated resources. UE 110 receives TRS from different TRPs at different frequency offsets based on the associated Doppler.

[0082] As shown in Figure 5, at time F c At time F, TRP1 501 transmits TRS1 511 to UE 110, and UE 110 transmits TRS1 511 at time F c +f D1 Received at time F c At time F, TRP1 501 transmits TRS1 511 to UE 110, and UE 110 transmits TRS1 511 to UE 110. c +f D1 Received at time Fc At time F, TRP2 502 transmits TRS2 512 to UE 110, and UE 110 transmits TRS2 512 to c +f D2 Received at time F c At time F, TRP3 503 transmits TRS3 513 to UE 110, and UE 110 transmits TRS3 513 to c +f D3 Receive at.

[0083] The UE 110 performs the operations directed by the "Doppler Configuration" frame transmitted at 510. In one case, the UE 110 is instructed to perform Doppler difference between TRP1 501 and TRP2 502 and between TRP1 501 and TRP3 503 on a single path. In this case, the UE 110 calculates the difference in receive frequency as "f d1 -f d2 " and "f d1 -f d3 (referring to 520 and 530, respectively) and reporting this information along with the validity of these measurements at time F c +f UE 5. The UE transmits the information to TRP1 501 (the associated TRP) in the uplink using a UE reporting frame 550. This information is shared between the TRPs using the backhaul links, and the TRPs pre-compensate the data as shown in FIG. 5. For example, as shown in FIG. 5, TRP1 501 transmits the information to TRP1 using the backhaul link 560. d1 -f d2 ” (520) calculation with TRP2 502, and TRP1 501 uses the backhaul link 570 to calculate “f d1 -f d3 " (530) calculation is shared with TRP3.

[0084] Time F c At time F, TRP1 501 transmits PDSCH 581 to UE 110. PDSCH 581 is c +f D1 UE 110 receives the signal F c +f D1 -fD2 At time F, TRP2 502 transmits PDSCH 582 to UE 110. PDSCH 582 is c +f D1 UE 110 receives the signal F c +f D1 -f D3 At time F, TRP3 503 transmits PDSCH 583 to UE 110. PDSCH 583 is c +f D1 is received by the UE 110 at

[0085] The Doppler parameter estimation and reporting method defined above has the following benefits and technical effects: The method reduces UL SRS overhead used for Doppler measurements and provides enhanced CSI measurement reporting for moving UEs. Doppler parameters are more accurate and reliable. Network efficiency is improved by utilizing Doppler information for any of the use cases described in [Tdoc No. R1-2203229 - "New WID: On CSI enhancements for Rel-18 NR MIMO evolution" R3]. Furthermore, the examples described herein may be relevant in the context of the Release 18 work items on downlink and uplink MIMO evolution.

[0086] 6 illustrates an example device 600 configured to implement examples described herein, which may be implemented in hardware. The device 600 includes at least one processor 602 (e.g., an FPGA and / or a CPU) and at least one memory 604 containing computer program code 605, where the at least one memory 604 and the computer program code 605 are configured to cause the device 600, using the at least one processor 602, to implement circuits, processes, components, modules, or functions (collectively, control 606) for implementing examples described herein, including advanced confidence-based trajectory prediction. The memory 604 may be non-transitory memory, transient memory, volatile memory (e.g., RAM), or non-volatile memory (e.g., ROM).

[0087] The device 600 optionally includes a display and / or I / O interface 608 that may be used to display aspects or status of the methods described herein (e.g., as one of the methods being performed or later) or to receive input from a user, such as using a keypad, camera, touchscreen, touch area, microphone, biometric recognition, one or more sensors, etc. The device 600 includes one or more communication, e.g., network (N / W) interfaces (I / F) 610. The communication I / F 610 may be wired and / or wireless and may communicate over the Internet / other networks by any communication technology. The communication I / F 610 may include one or more transmitters and one or more receivers. The communication I / F 610 may include standard known components such as amplifiers, filters, frequency converters, modulators (demodulators), and encoder / decoder circuits, as well as one or more antennas.

[0088] 4 and 5, as well as the UE 110, the RAN node 170 (e.g., gNB), or the network element 190. Accordingly, the processor 602 may correspond to the processor 120, the processor 152, and / or the processor 175; the memory 604 may correspond to the memory 125, the memory 155, and / or the memory 171; the computer program code 605 may correspond to the computer program code 123, the module 140-1, the module 140-2, and / or the computer program code 153, the module 150-1, the module 150-2, and / or the computer program code 173 or the module 177; and the communication I / F 610 may correspond to the transceiver 130, the antenna 128, the transceiver 160, the antenna 158, the N / WI / F 161, and / or the N / WI / F 180. Alternatively, for example, when the device 600 may be part of a self-organizing / optimizing network (SON) node, such as in a cloud, the device 600 may not correspond to a UE 110, a RAN node 170, a network element 190, or any of the TRPs shown in Figures 4 and 5.

[0089] The device 600 may also be distributed throughout the network (e.g., 100), including within and between the device 600 and any network elements (such as a network control element (NCE) 190 and / or a RAN node 170 and / or a UE 110, and / or any of the TRPs shown in Figures 4 and 5).

[0090] Interface 612 enables data communication between various items of device 600, as shown in Figure 6. For example, interface 612 may be one or more buses, such as an address bus, a data bus, or a control bus, or may include any interconnection mechanism, such as a series of wires on a motherboard or integrated circuit, optical fiber, or other optical communication equipment. Computer program code 605, including control 606, may include object-oriented software configured to pass data / messages between objects in computer program code 605. Device 600 need not include each and every feature described, or may include other features as well.

[0091] FIG. 7 shows a schematic diagram of non-volatile memory media 700a (e.g., a computer disk (CD) or digital versatile disk (DVD)) and 700b (e.g., a universal serial bus (USB) memory stick) that store instructions and / or parameters 702 that, when executed by a processor, enable the processor to perform one or more of the steps of the methods described above.

[0092] It should be noted that the exemplary embodiments may be implemented as circuitry in software, hardware, application logic, or a combination of software, hardware, and application logic. In the exemplary embodiments, the application logic, software, or instruction set is carried on any computer-readable medium. In the context of this disclosure, a "computer-readable medium" may be any medium or means that can contain, store, communicate, propagate, or transfer instructions for use by or associated with an instruction execution system, apparatus, or device, such as a base station, TRP, network node, or user equipment of the exemplary embodiments described above.

[0093] 8 is an example method 800. At 810, the method includes receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured. At 820, the method includes performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal. At 830, the method includes determining whether the at least one validity condition associated with the at least one measurement is valid. At 840, the method includes reporting the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network. Method 800 may be performed in user equipment (e.g., UE 110).

[0094] 9 is an example method 900. At 910, the method includes transmitting a tracking reference signal configuration to user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured. At 920, the method includes receiving a report from the user equipment including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid. At 930, the method includes transmitting the at least one measurement and the determination of whether the at least one validity condition is valid to at least one transmission / reception point using a backhaul link. Method 900 may be performed in a network node (e.g., RAN node 170 or network element 190).

[0095] The following examples (1 to 25) are provided and described herein. [Example]

[0096] 1. An apparatus comprising: means for receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; means for performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; means for determining whether the at least one validity condition associated with the at least one measurement is valid; and means for reporting the at least one measurement of the at least one parameter and a determination of whether the at least one validity condition is valid to the network. [Example]

[0097] 2. The apparatus of embodiment 1, wherein the configuration includes an indication of at least one resource including an anchor resource used in the Doppler information calculation, the anchor resource being associated with the anchor transmitting and receiving point. [Example]

[0098] 3. The apparatus of example 2, wherein the Doppler information calculation includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency difference, a relative signal time difference, or a time difference of arrival. [Example]

[0099] 4. The apparatus of any one of claims 1 to 3, wherein the at least one parameter includes multipath Doppler information. [Example]

[0100] 5. The apparatus of embodiment 4, wherein the Doppler information includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency, a Doppler spectrum, a quantized Doppler value having a number of bits, or a quantized Doppler difference value having a number of bits. [Example]

[0101] 6. The apparatus of any one of embodiments 1 to 5, wherein at least one validity condition is based on a multipath power difference between one or more dominant multipath components, specific to a transmitting / receiving point (TRP) or between TRPs. [Example]

[0102] 7. The apparatus of any one of embodiments 1 to 6, wherein at least one validity condition is based on a transmitting / receiving point (TRP)-specific or inter-TRP tracking reference signal resource application time for Doppler difference calculation. [Example]

[0103] 8. The apparatus of any of Examples 1 to 7, wherein at least one validity condition is based on a transmit / receive point (TRP)-specific or inter-TRP measurement time difference for Doppler difference calculation. [Example]

[0104] 9. The apparatus of any of examples 1-8, wherein at least one validity condition is based on a time-of-arrival calculation of a transmitting / receiving point (TRP) specific tracking reference signal. [Example]

[0105] 10. The apparatus of any of examples 1 to 9, wherein at least one validity condition is based on a reporting time offset. [Example]

[0106] 11. The apparatus of any of Examples 1 to 10, wherein reporting of the determination of whether at least one validity condition is valid includes a default mode for when at least one validity condition is valid. [Example]

[0107] 12. An apparatus as described in any one of Examples 1 to 11, wherein reporting of the determination of whether at least one validity condition is valid includes a fallback mode for when at least one of the at least one validity condition is not valid. [Example]

[0108] 1. An apparatus comprising: means for transmitting a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; means for receiving from the user equipment a report including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and means for transmitting, using a backhaul link, to at least one transmission / reception point, the at least one measurement and the determination of whether the at least one validity condition is valid. [Example]

[0109] 14. The apparatus of embodiment 13, wherein the configuration includes an indication of at least one resource including an anchor resource used in the Doppler information calculation, the anchor resource being associated with the anchor transmitting and receiving point. [Example]

[0110] 15. The apparatus of example 14, wherein the Doppler information calculation includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency difference, a relative signal time difference, or a time difference of arrival. [Example]

[0111] 16. The apparatus of any of Examples 13 to 15, wherein at least one parameter includes multipath Doppler information. [Example]

[0112] 17. The apparatus of claim 16, wherein the Doppler information includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency, a Doppler spectrum, a quantized Doppler value having a number of bits, or a quantized Doppler difference value having a number of bits. [Example]

[0113] 18. The apparatus of any one of Examples 13 to 17, wherein the at least one validity condition is based on at least one of a transmitting / receiving point (TRP)-specific or inter-TRP multipath power difference between one or more dominant multipath components, a TRP-specific or inter-TRP tracking reference signal resource application time for Doppler difference calculation, a TRP-specific or inter-TRP measurement time difference for Doppler difference calculation, a TRP-specific tracking reference signal arrival time calculation, or a reporting time offset. [Example]

[0114] 19. The apparatus of any of Examples 13 to 18, wherein reporting of the determination of whether at least one validity condition is valid includes a default mode and a fallback mode, the default mode being for when at least one validity condition is valid and the fallback mode being for when at least one of the at least one validity condition is not valid. [Example]

[0115] 1. An apparatus comprising: at least one processor; and at least one memory containing computer program code, the at least one memory and the computer program code configured to cause, using the at least one processor, the apparatus to at least: receive a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; perform at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; determine whether the at least one validity condition associated with the at least one measurement is valid; and report the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network. [Example]

[0116] 1. An apparatus comprising: at least one processor; and at least one memory containing computer program code, wherein the at least one memory and the computer program code are configured, using the at least one processor, to cause the apparatus to at least: transmit a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; receive from the user equipment a report including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and transmit, to at least one transmission / reception point, using a backhaul link, the at least one measurement and the determination of whether the at least one validity condition is valid. [Example]

[0117] A machine-readable non-transitory program storage device tangibly embodying a program of instructions executable by a machine to perform operations, the operations including: receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; determining whether the at least one validity condition associated with the at least one measurement is valid; and reporting the at least one measurement of the at least one parameter and the determination of whether the at least one validity condition is valid to the network. [Example]

[0118] 1. A machine-readable, non-transitory program storage device tangibly embodying a program of instructions executable by a machine to perform operations, the operations including: transmitting a tracking reference signal configuration to user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; receiving a report from the user equipment including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and transmitting, using a backhaul link, to at least one transmission / reception point, the at least one measurement and the determination of whether the at least one validity condition is valid. [Example]

[0119] 1. A method comprising: receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; performing at least one measurement of the at least one parameter using the configuration, the at least one parameter associated with the tracking reference signal; determining whether the at least one validity condition associated with the at least one measurement is valid; and reporting the at least one measurement of the at least one parameter and a determination of whether the at least one validity condition is valid to the network. [Example]

[0120] 25. The method of embodiment 24, wherein the configuration includes an indication of at least one resource including an anchor resource used in the Doppler information calculation, the anchor resource being associated with the anchor transmitting / receiving point. [Example]

[0121] 26. The method of embodiment 25, wherein the Doppler information calculation includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency difference, a relative signal time difference, or a time difference of arrival. [Example]

[0122] 27. The method of any of embodiments 24 to 26, wherein the at least one parameter includes multipath Doppler information. [Example]

[0123] 28. The method of embodiment 27, wherein the Doppler information includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency, a Doppler spectrum, a quantized Doppler value having a number of bits, or a quantized Doppler difference value having a number of bits. [Example]

[0124] 29. The method of any of embodiments 24 to 28, wherein at least one validity condition is based on a multipath power difference between one or more dominant multipath components, either transmit / receive point (TRP) specific or inter-TRP. [Example]

[0125] 30. The method of any one of examples 24 to 29, wherein at least one validity condition is based on a transmitting / receiving point (TRP)-specific or inter-TRP tracking reference signal resource application time for Doppler difference calculation. [Example]

[0126] 31. The method of any of Examples 24 to 30, wherein at least one validity condition is based on a transmit / receive point (TRP)-specific or inter-TRP measurement time difference for Doppler difference calculation. [Example]

[0127] 32. The method of any of examples 24-31, wherein at least one validity condition is based on a time-of-arrival calculation of a transmitting / receiving point (TRP) specific tracking reference signal. [Example]

[0128] 33. The method of any of Examples 24 to 32, wherein at least one validity condition is based on a reporting time offset. [Example]

[0129] 34. The method of any of Examples 24 to 33, wherein reporting the determination of whether at least one validity condition is valid includes a default mode for when at least one validity condition is valid. [Example]

[0130] 35. The method of any of examples 24 to 34, wherein reporting the determination of whether at least one validity condition is valid includes a fallback mode for when at least one of the at least one validity condition is not valid. [Example]

[0131] 1. A method comprising: transmitting a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; receiving a report from the user equipment including at least one measurement of the at least one parameter, the at least one parameter associated with the tracking reference signal, and a determination of whether the at least one validity condition is valid; and transmitting the at least one measurement and the determination of whether the at least one validity condition is valid to at least one transmission / reception point using a backhaul link. [Example]

[0132] 37. The method of embodiment 36, wherein the configuration includes an indication of at least one resource including an anchor resource used in the Doppler information calculation, the anchor resource being associated with the anchor transmitting / receiving point. [Example]

[0133] 38. The method of embodiment 37, wherein the Doppler information calculation includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency difference, a relative signal time difference, or a time of arrival difference. [Example]

[0134] 39. The method of any one of examples 36 to 38, wherein the at least one parameter includes multipath Doppler information. [Example]

[0135] The method of example 39, wherein the Doppler information includes at least one of a multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with the anchor transmitting / receiving point and a resource associated with another transmitting / receiving point, a Doppler frequency, a Doppler spectrum, a quantized Doppler value having several bits, or a quantized Doppler difference value having several bits. [Example]

[0136] 41. The method of any one of Examples 36 to 40, wherein at least one validity condition is based on at least one of a transmitting / receiving point (TRP)-specific or inter-TRP multipath power difference between one or more dominant multipath components, a TRP-specific or inter-TRP tracking reference signal resource application time for Doppler difference calculation, a TRP-specific or inter-TRP measurement time difference for Doppler difference calculation, a TRP-specific tracking reference signal arrival time calculation, or a reporting time offset. [Example]

[0137] 42. The method of any of Examples 36 to 41, wherein reporting of the determination of whether at least one validity condition is valid includes a default mode and a fallback mode, the default mode being for when at least one validity condition is valid and the fallback mode being for when at least one of the at least one validity condition is not valid.

[0138] References to "computer," "processor," etc. should be understood to encompass computers having different architectures, such as single / multi-processor architectures and serial or parallel architectures, as well as special purpose circuitry, such as field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), signal processing devices, and other processing circuitry. References to computer programs, instructions, code, etc. should be understood to encompass software for programmable processors or firmware, e.g., the programmable contents of a hardware device, whether instructions for a processor, or configuration settings for a fixed function device, gate array, or programmable logic device.

[0139] The memories described herein 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, non-transitory memory, transient memory, fixed memory and removable memory, etc. The memories may include databases for storing data.

[0140] As used herein, the term "circuit" may refer to: (a) hardware circuit implementations, such as analog and / or digital circuit implementations, and (b) combinations of circuitry and software (and / or firmware), such as (where applicable) (i) a combination of a processor or (ii) a portion of a processor / software, including a digital signal processor, software, and memory, that work together to cause a device to perform various functions, and (c) a circuit, such as a microprocessor or portion of a microprocessor, that requires software or firmware for operation, even if the software or firmware is not physically present. As a further example, as used herein, the term "circuit" also encompasses implementations of simply a processor (or processors), or portion of a processor, and its (or their) accompanying software and / or firmware. The term "circuit" also encompasses, for example, and where applicable to the particular element, a baseband integrated circuit or an application processor integrated circuit for a mobile phone, or a similar integrated circuit in a server, cellular network device, or another network device.

[0141] In the diagram, arrows between individual blocks represent the operational connections between them and the direction of data flow with respect to those connections.

[0142] It should be understood that the foregoing description is merely illustrative. Various alternatives and modifications may be devised by those skilled in the art. For example, the features recited in the various dependent claims may be combined with each other in any suitable combination. In addition, features from different exemplary embodiments described above may be selectively combined into new exemplary embodiments. Accordingly, this description is intended to embrace all such alternatives, modifications, and variations that fall within the scope of the appended claims.

[0143] The following acronyms and abbreviations that may be found in the specification and / or drawings are defined as follows (abbreviations and acronyms may be attached to each other or to other characters using, for example, a dash or hyphen): 4G 4th Generation 5G (5th Generation) 5GC 5G Core Network AI artificial intelligence AMF Access and Mobility Management Functions AP aperiodic ASIC Application Specific Integrated Circuit BW Bandwidth CJT Coherent Joint Transmission CoMP Coordinated Multipoint CP Cyclic Prefix CP-OFDM Cyclic Prefix Orthogonal Frequency Division Multiplexing CPU Central Processing Unit CSI Channel State / Status Information CU Central Unit or Centralized Unit DCI Downlink Control Information DL Downlink DMRS or DM-RS demodulation reference signal DSP Digital Signal Processor DU Distributed Unit eNB Evolved Node B (e.g., LTE base station) EN-DC E-UTRAN New Radio - Dual Connectivity en-gNB: A node that provides NR user plane and control plane protocol termination for UE and acts as a secondary node in EN-DC. E-UTRA Evolved Universal Terrestrial Radio Access, i.e. LTE radio access technology E-UTRAN E-UTRA network F1 Interface between CU and DU FDD Frequency Division Duplex FPGA Field Programmable Gate Array FR Frequency Range gNB: A base station for 5G / NR, i.e., a node that provides NR user plane and control plane protocol termination for UEs and is connected to 5GC via the NG interface. HST high speed train IAB Integrated Access Backhaul ID Identifier I / F interface JT Joint Transmission I / O Input / Output L-bit L-bit number LMF location management function LoS line of sight LTE Long Term Evolution (4G) MAC Media Access Control max maximum MCS Modulation and Coding Scheme M-IDFT Inverse Discrete Fourier Transform of size M MIMO multiple input multiple output ML Machine Learning MME Mobility Management Entity MRO Mobility Robustness Optimization mTRP Multiple TRP MU Multi-User NCE Network Control Element NCJT or NC-JT Noncoherent Joint Transmission ng or NG New Generation ng-eNB New generation eNB NG-RAN New Generation Radio Access Network NR New Radio (5G) N / W Network NZP Non-Zero Power OFDM Orthogonal Frequency Division Multiplexing P is the number of consecutive TRS transmission opportunities, e.g., P PCI Physical Cell Identifier PDA Personal Digital Assistant PDCP Packet Data Convergence Protocol PDSCH Physical Downlink Shared Channel PHY physical layer PRB Physical Resource Block pre-comp advance compensation PUSCH Physical Uplink Shared Channel P / SP Periodic or Semi-Permanent Q bit vector length QCL pseudo-collocation R1 Wireless Layer 1 RAM Random Access Memory RAN Radio Access Network Rel- Release RIC RAN Intelligent Controller RLC Radio Link Control ROM Read-Only Memory RP RAN Meeting RRC Radio Resource Control (protocol) RRH Remote Radio Head RS reference signal RSRP reference signal received power RU Wireless Unit Rx or RX Receiver or Receiving SDAP Service Data Adaptation Protocol SFN Single Frequency Network SGW Serving Gateway SINR Signal to Interference and Noise Ratio SMF Session Management Facility SON Self-organizing / optimizing network SP Semi-permanent SRS Sounding Reference Signal SSB sync signal block sTRP Single TRP TCI Transmit Configuration Indication TDD Time Division Duplex Tdoc technical documentation TRP sending and receiving point trs or TRS tracking reference signal TS Technical Specifications Tx or TX Transmitter or Transmit Conventional Dual-Codebook Structure for Type-I CSI Feedback Feedback Targeted High-Resolution CSI Acquisition for Type II Multi-User Multiple-Input Multiple-Output (MU-MIMO) Operation UAV unmanned aerial vehicle UE User Equipment (e.g., wireless, generally, mobile device) UL Uplink UPF User Plane Function URLLC: Ultra-reliable, low-latency communication WID Work Item Description X2 Network interface between RAN nodes and between RAN and core network Network interface between Xn NG-RAN nodes

Claims

1. 1. An apparatus comprising: means for receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; means for performing at least one measurement of at least one parameter using the arrangement, the at least one parameter being related to a tracking reference signal; means for determining whether at least one validity condition associated with at least one measurement is valid; means for reporting to the network at least one measurement of the at least one parameter and a determination of whether the at least one validity condition is valid; An apparatus comprising:

2. The apparatus of claim 1 , wherein the configuration includes an indication of at least one resource including an anchor resource used in the Doppler information calculation, the anchor resource being associated with an anchor transmitting / receiving point.

3. Doppler information calculation is Multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with an anchor transmitting / receiving point and a resource associated with another transmitting / receiving point; Doppler frequency difference, Relative signal time difference, or Arrival time difference, The apparatus of claim 2 , comprising at least one of:

4. 4. The apparatus of claim 1, wherein at least one parameter includes multipath Doppler information.

5. Doppler information is Multipath Doppler shift, a multipath Doppler shift difference between an anchor resource associated with an anchor transmitting / receiving point and a resource associated with another transmitting / receiving point; Doppler frequency, Doppler spectrum, a quantized Doppler value with a number of bits, or a quantized Doppler difference value having a number of bits, The apparatus of claim 4 , comprising at least one of:

6. The apparatus of claim 1 , wherein at least one validity condition is based on a multipath power difference between several one or more dominant multipath components, either transmit / receive point (TRP) specific or inter-TRP.

7. The apparatus of claim 1 , wherein at least one validity condition is based on a transmitting / receiving point (TRP)-specific or inter-TRP tracking reference signal resource application time for Doppler difference calculation.

8. The apparatus of claim 1 , wherein at least one validity condition is based on a transmit / receive point (TRP)-specific or inter-TRP measurement time difference for Doppler difference calculation.

9. The apparatus of claim 1 , wherein at least one validity condition is based on a time-of-arrival calculation of a transmitting / receiving point (TRP) specific tracking reference signal.

10. The apparatus of claim 1 , wherein at least one validity condition is based on a reporting time offset.

11. 11. The apparatus of claim 1, wherein reporting of the determination of whether at least one validity condition is valid includes a default mode for when at least one validity condition is valid.

12. 12. The apparatus of claim 1, wherein reporting the determination of whether at least one validity condition is valid includes a fallback mode for when at least one of the at least one validity condition is not valid.

13. 1. An apparatus comprising: means for transmitting a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; means for receiving, from the user equipment, a report including at least one measurement of at least one parameter, at least one parameter associated with the tracking reference signal, and a determination of whether at least one validity condition is valid; means for transmitting, to at least one transmitting / receiving point, using a backhaul link, the at least one measurement and a determination of whether the at least one validity condition is valid; An apparatus comprising:

14. 1. A method comprising: receiving a tracking reference signal configuration from a network, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; performing at least one measurement of at least one parameter using the arrangement, the at least one parameter being related to the tracking reference signal; determining whether at least one validity condition associated with the at least one measurement is valid; reporting to the network at least one measurement of the at least one parameter and a determination of whether the at least one validity condition is valid; A method comprising:

15. 1. A method comprising: transmitting a tracking reference signal configuration to a user equipment, the configuration including at least one parameter to be measured and at least one validity condition associated with the at least one parameter to be measured; receiving, from the user equipment, a report including at least one measurement of at least one parameter, at least one parameter associated with the tracking reference signal, and a determination of whether at least one validity condition is valid; transmitting, to at least one transmitting / receiving point, using a backhaul link, the at least one measurement and a determination of whether the at least one validity condition is valid; A method comprising:

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