Methods, apparatuses, systems, and readable media for communication

Abstract

A method, apparatus, system, and readable medium for communication are disclosed, where the method for communication includes receiving, from a user equipment, information indicating at least one or more channel characteristics of one or more received positioning reference signals of a set of frequency hops and one or more identifiers of one or more missed positioning reference signals of the set of frequency hops; and compensating for the one or more missed positioning reference signals of the set of frequency hops based at least in part on the information.

Description

TECHNICAL FIELD

[0001] The following example embodiments relate to wireless communications and positioning. BACKGROUND

[0002] Positioning is a process that can be used to estimate a location of a device. It is desirable to improve positioning accuracy in order to more accurately estimate a location of a device. SUMMARY

[0003] The scope of protection sought for various example embodiments is defined by the independent claims. Example embodiments and features that are not the subject of independent claims are to be interpreted as examples useful for understanding various embodiments, if any.

[0004] According to one aspect, there is provided an apparatus comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to receive, from a user equipment, information indicating at least one or more channel characteristics of one or more received positioning reference signals of a frequency-hopping set and one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set; and compensate, based at least in part on the information, for the one or more missed positioning reference signals of the frequency-hopping set.

[0005] According to another aspect, there is provided an apparatus comprising means for receiving, from a user equipment, information indicating at least one or more channel characteristics of one or more received positioning reference signals of a frequency-hopping set and one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set; and means for compensating, based at least in part on the information, for the one or more missed positioning reference signals of the frequency-hopping set.

[0006] According to another aspect, there is provided a method comprising receiving, from a user equipment, information indicating at least one or more channel characteristics of one or more received positioning reference signals of a frequency-hopping set and one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set; and compensating, based at least in part on the information, for the one or more missed positioning reference signals of the frequency-hopping set.

[0007] According to another aspect, there is provided a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a user equipment, information indicating at least one or more channel characteristics of one or more received positioning reference signals of a frequency-hopping set and one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set; and compensating, based at least in part on the information, for the one or more missed positioning reference signals of the frequency-hopping set.

[0008] According to another aspect, there is provided a computer-readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receive, from a user equipment, information indicating at least one or more channel characteristics of one or more received positioning reference signals of a frequency-hopping set and one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set; and compensate for the one or more missed positioning reference signals of the frequency-hopping set based at least in part on the information.

[0009] According to another aspect, there is provided a non-transitory computer-readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receive, from a user equipment, information indicating at least one or more channel characteristics of one or more received positioning reference signals of a frequency-hopping set and one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set; and compensate for the one or more missed positioning reference signals of the frequency-hopping set based at least in part on the information.

[0010] According to another aspect, there is provided an apparatus comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: determine one or more identifiers of one or more missed positioning reference signals of a frequency-hopping set; and send, to a location management entity, information indicating at least one or more channel characteristics of one or more received positioning reference signals of the frequency-hopping set and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set.

[0011] According to another aspect, there is provided an apparatus comprising: means for determining one or more identifiers of one or more missed positioning reference signals of a frequency-hopping set; and means for sending, to a location management entity, information indicating at least one or more channel characteristics of one or more received positioning reference signals of the frequency-hopping set and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set.

[0012] According to another aspect, there is provided a method comprising: determining one or more identifiers of one or more missed positioning reference signals of a frequency-hopping set; and sending, to a location management entity, information indicating at least one or more channel characteristics of one or more received positioning reference signals of the frequency-hopping set and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set.

[0013] According to another aspect, there is provided a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: determining one or more identifiers of one or more missed positioning reference signals of a frequency-hopping set; and transmitting, to a location management entity, information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency-hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set.

[0014] According to another aspect, there is provided a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: determining one or more identifiers of one or more missed positioning reference signals of a frequency-hopping set; and transmitting, to a location management entity, information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency-hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set.

[0015] According to another aspect, there is provided a non-transitory computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: determining one or more identifiers of one or more missed positioning reference signals of a frequency-hopping set; and transmitting, to a location management entity, information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency-hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set.

[0016] According to another aspect, there is provided a system comprising at least a user equipment and a location management entity. The user equipment is configured to: determine one or more identifiers of one or more missed positioning reference signals of a frequency-hopping set; and transmit, to the location management entity, information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency-hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set. The location management entity is configured to: receive the information from the user equipment; and compensate for the one or more missed positioning reference signals of the frequency-hopping set based at least in part on the information.

[0017] According to another aspect, there is provided a system comprising at least a user equipment and a location management entity. The user equipment comprises: means for determining one or more identifiers of one or more missed positioning reference signals of a frequency hopping set; and means for transmitting, to the location management entity, information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency hopping set. The location management entity comprises: means for receiving, from the user equipment, the above-mentioned information; and means for compensating for the one or more missed positioning reference signals of the frequency hopping set based at least in part on the information. BRIEF DESCRIPTION OF DRAWINGS

[0018] In the following, various example embodiments will be described in more detail with reference to the accompanying drawings, in which:

[0019] Figure 1 An example of a wireless communication network is illustrated;

[0020] Figure 2 An example of a discontinuous reception cycle is illustrated;

[0021] Figure 3 An example of a solution for an overlapping frequency hopping positioning measurement technique with phase compensation is illustrated;

[0022] Figure 4 An example of a misalignment between a positioning reference signal and a discontinuous reception is illustrated;

[0023] Figure 5A An example of a missed positioning reference signal interval is illustrated;

[0024] Figure 5B An example of a missed positioning reference signal interval is illustrated;

[0025] Figure 5C An example of a missed positioning reference signal interval is illustrated;

[0026] Figure 6A An example of a missed positioning reference signal interval is illustrated;

[0027] Figure 6B An example of replacing a missed positioning reference signal interval with a previous positioning reference signal interval is illustrated;

[0028] Figure 7 A signal flow diagram is illustrated;

[0029] Figure 8 A signal flow diagram is illustrated;

[0030] Figure 9 A signal flow diagram is illustrated;

[0031] Figure 10 a flowchart is illustrated;

[0032] Figure 11 a flowchart is illustrated;

[0033] Figure 12 a flowchart is illustrated;

[0034] Figure 13 an example of an apparatus is illustrated; and

[0035] Figure 14 an example of an apparatus is illustrated. DETAILED DESCRIPTION

[0036] The following examples are illustrative. Although the specification can contain many specifics, these are not intended to limit the scope of the application but merely to illustrate many embodiments. Specific details can be omitted for the sake of clarity. Although the term "an embodiment" or "one embodiment" can be used herein to describe various embodiments, the term "one embodiment" or "an embodiment" is not intended to mean the same embodiment or the same version, but is intended to mean a specific embodiment. Various specific features, objects or embodiments can be combined or separated in various ways.

[0037] Some example embodiments described herein can be implemented in a wireless communication network comprising a radio access network based on one or more of the following radio access technologies (RATs): Global System for Mobile Communications (GSM) or any other second generation radio access technology, Universal Mobile Telecommunication System (UMTS, 3G) based on basic wideband code division multiple access (W-CDMA), High-Speed Packet Access (HSPA), Long Term Evolution (LTE), LTE-Advanced, Fourth Generation (4G), Fifth Generation (5G), 5G New Radio (NR), Advanced 5G (i.e., 3GPP NR Rel-18 and beyond), or Sixth Generation (6G). Some examples of a radio access network include a Universal Mobile Telecommunication System (UMTS) radio access network (UTRAN), an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), or a Next Generation Radio Access Network (NG-RAN). The wireless communication network can also comprise a core network, and some example embodiments can also apply to network functions of the core network.

[0038] It should be noted that the embodiments are not limited to the wireless communication network given as an example, but a person skilled in the art can apply the solution to other wireless communication networks or systems having the necessary features. For example, some example embodiments can also apply to a communication system based on IEEE 802.11 specifications, or a communication system based on IEEE 802.15 specifications. IEEE is an abbreviation of the Institute of Electrical and Electronics Engineers.

[0039] Figure 1An example of a simplified wireless communication network is depicted, showing some physical and logical entities. Figure 1 The shown connections can be physical or logical connections. It is clear to a person skilled in the art that the wireless communication network can also comprise other physical and logical entities than the ones shown. Figure 1 The shown physical and logical entities can be supplemented by other physical and logical entities.

[0040] However, the example embodiments described herein are not limited to the wireless communication network given as an example, but a person skilled in the art can apply the embodiments described herein to other wireless communication networks having the necessary characteristics.

[0041] Figure 1 The example wireless communication network shown comprises an access network, such as a Radio Access Network (RAN), and a core network 110.

[0042] Figure 1 User equipments (UEs) 100, 102 are shown that are configured to wirelessly connect with an access node (AN) 104 of the access network on one or more communication channels in a radio cell. The AN 104 can be an evolved NodeB (abbreviated as eNB or eNodeB), a next generation evolved NodeB (abbreviated as ng-eNB), or a next generation NodeB (abbreviated as gNB or gNodeB) providing the radio cell. The wireless connection (e.g., radio link) from a UE to the access node 104 can be referred to as uplink (UL) or reverse link, and the wireless connection (e.g., radio link) from the access node to the UE can be referred to as downlink (DL) or forward link. The UE 100 can also communicate directly with the UE 102 via a wireless connection, commonly referred to as a sidelink (SL), and vice versa. It will be appreciated that the access node 104 or its functionalities can be implemented using any node, host, server or access point, etc. entity suitable for providing such functionalities.

[0043] The access network can comprise more than one access node, in which case the access nodes can also be configured to communicate with each other, either through wired or wireless links. These links between access nodes can be used to send and receive control plane signaling, and can also be used to route data from one access node to another.

[0044] An access node can comprise a computing device configured to control radio resources of the access node. An access node can also be referred to as a base station, a base transceiver station (BTS), an access point, a cell site, a radio access node, or any other type of node capable of wireless connectivity with UEs (e.g., UEs 100, 102). An access node can include or be coupled to a transceiver. From the transceiver of an access node, a connection can be provided to an antenna unit that establishes bi-directional radio links to UEs 100, 102. An antenna unit can include an antenna or antenna element, or multiple antennas or antenna elements.

[0045] Access node 104 can further be connected to a core network (CN) 110. Core network 110 can comprise an evolved packet core (EPC) network and / or a fifth generation core network (5GC). The EPC can comprise network entities such as a serving gateway (S-GW) for routing and forwarding data packets, a packet data network gateway (P-GW) for providing connectivity to external packet data networks for UEs, and a mobility management entity (MME). The 5GC can comprise network functions such as a user plane function (UPF), an access and mobility management function (AMF) 111, and a location management function (LMF) 112.

[0046] With respect to positioning, the core network 110 can include a 5GC with a service-based architecture. The 5GC can include various network functions, including an AMF 111 and an LMF 112. The AMF 111 can be configured to provide location information to other network functions in the core network 110, as well as to other entities that request positioning of UEs 100, 102 for call processing, mobility policy enforcement, and charging purposes. The AMF 111 can receive and manage location requests from several entities: mobile originating location requests (MO-LRs) received from UEs 100, 102, and mobile terminating location requests (MT-LRs) directed to other functions of the core network or access network. The AMF 111 can select an LMF 112 for a given request and trigger a positioning session using its location services. The LMF 112 can then perform positioning after receiving such a request from the AMF 111. The LMF 112 can manage resources and timing of positioning activities. The LMF 112 can obtain location information for a UE 100, 102 by at least one of: issuing a Namf_Communication service request to one or more access nodes via an NL1 interface for network-based positioning; or communicating with the UE over an N1 interface for UE-based or UE-assisted positioning. The location information obtained by the LMF 112 can include a location estimate for the UE 100, 102, and in addition, the LMF 112 can also estimate a velocity or accuracy of the location information when requested. In terms of connectivity, the AMF 111 can be located between the access node 104 and the LMF 112, and thus closer to the access node than the LMF.

[0047] The core network 110 can also be capable of communicating with, or utilizing services provided by, one or more external networks 113, such as a public switched telephone network or the Internet. For example, in a 5G wireless communication network, a UPF of the core network 110 can be configured to communicate with external data networks via an N6 interface. In an LTE wireless communication network, a P-GW of the core network 110 can be configured to communicate with external data networks.

[0048] The illustrated UEs 100, 102 are one type of device that can be allocated and assigned resources on the air interface. The UEs 100, 102 can also be referred to as wireless communication devices, subscriber units, mobile stations, remote terminals, access terminals, user terminals, terminal devices, or user equipment, to name a few. UEs can be computing devices that operate with or without a subscriber identification module (SIM), including, but not limited to, the following types of computing devices: mobile phones, smartphones, personal digital assistants (PDAs), handheld devices, computing devices including wireless modems (e.g., alarm or meter devices), laptop computers, desktop computers, tablet computers, game consoles, netbooks, wearable devices (e.g., watches, headphones, or glasses) with radio parts, sensors including wireless modems, or any computing device including a wireless modem integrated in a vehicle.

[0049] Any feature described herein with a UE can also be implemented with a corresponding apparatus such as a relay node. An example of such a relay node can be a layer 3 relay towards an access node (self-backhauling relay). A self-backhauling relay node can also be referred to as an integrated access and backhaul (IAB) node. An IAB node can comprise two logical parts: a mobile termination (MT) part responsible for the backhaul link(s) (i.e., the link(s) between the IAB node and a donor node (also referred to as parent node)) and a distributed unit (DU) part responsible for the access link(s) (i.e., the child link(s) between the IAB node and UE(s), and / or child link(s) between the IAB node and other IAB nodes (multi-hop scenario)).

[0050] Another example of such a relay node can be a layer 1 relay, referred to as a repeater. A repeater can amplify and forward signals received from an access node to a UE and / or amplify and forward signals received from a UE to an access node.

[0051] It should be appreciated that a UE can also be an almost exclusively uplink only device, an example of which can be a camera or camcorder loading images or video clips to a network. A UE can also be a device with the capability to operate in an Internet of Things (IoT) network, which is a scenario where objects can be provided with the ability to transfer data over a network without requiring human-to-human, or human-to-computer interaction. A UE can also leverage the cloud. In some applications, computation can be performed in the cloud or in another UE.

[0052] A wireless communication network can also be capable of supporting the use of cloud services, for example, at least a portion of core network operations can be performed as a cloud service (this is sometimes referred to as a “cloudified” core network). This can be done, for example, to take advantage of the economies of scale and the lower cost of cloud computing resources, to increase the agility of the core network, and / or to facilitate the use of the core network by MNOs that lack the infrastructure to operate their own core network. Figure 1The wireless communication network can further comprise a central control entity, etc., to provide facilities for the wireless communication networks of different operators to cooperate, e.g., in terms of spectrum sharing.

[0053] The various techniques described herein can also be applied to a cyber-physical system (CPS) (a system of collaborating computational elements controlling physical entities). CPS can enable the implementation and exploitation of massive amounts of interconnected ICT devices (sensors, actuators, processors microcontrollers, etc.) embedded in physical objects at different locations. Mobile cyber-physical systems is a subcategory of cyber-physical systems where the physical system in question can have inherent mobility. Examples of mobile cyber-physical systems include mobile robots and electronic devices transported by humans or animals.

[0054] 5G enables usage of multiple input - multiple output (MIMO) antennas in the access nodes 104 and / or the UEs 100, 102, much more than the base stations or access nodes of LTE networks (the so-called small cell concept), including macro sites operating in co-operation with smaller stations and using various radio technologies depending on service demands, use cases and / or available spectrum. The 5G wireless communications networks can support a wide array of use cases and related applications, including video streaming, augmented reality, different ways of data sharing and various forms of machine type communications, such as (massive) machine-type communications (mMTC), including vehicle safety, different sensors and real-time control.

[0055] In the 5G wireless communications networks, the access nodes and / or UEs can have multiple radio interfaces, i.e., below 6 GHz, cmWave and mmWave, and can also be integrated with existing legacy radio access technologies, such as LTE. The integration with LTE can be implemented as a system where macro coverage can be provided by LTE and 5G radio interface access can come from small cells by aggregation to LTE. In other words, the 5G wireless communications networks can support both inter-RAT operability, such as LTE-5G, and inter-RI operability (inter-radio interface operability), such as below 6 GHz - cmWave - mmWave. One of the concepts considered to be used in the 5G wireless communications networks can be network slicing, where multiple independent and dedicated virtual sub-networks (network instances) can be created within the basically same infrastructure to run services with different requirements on latency, reliability, throughput and mobility.

[0056] 5G can enable analytics and knowledge generation to occur at the data source. This approach can involve leveraging resources that can not have persistent connectivity to a network, such as laptops, smartphones, tablets, and sensors. Multi-access edge computing (MEC) can provide a distributed computing environment for application and service hosting. It can also have the ability to store and process content in close proximity to cellular subscribers for faster response times. Edge computing can encompass a wide range of technologies, such as wireless sensor networks, mobile data acquisition, mobile signature analysis, cooperative distributed peer-to-peer ad hoc networking and processing, and can also be classified as local cloud / fog computing and grid / mesh computing, dew computing, mobile edge computing, cloudlets, distributed data storage and retrieval, self-healing networks, remote cloud services, augmented and virtual reality, data caching, Internet of Things (massive connectivity and / or latency critical), critical communications (autonomous vehicles, traffic safety, real-time analytics, time-critical control, healthcare applications).

[0057] In some example embodiments, an access node (e.g., access node 104) can comprise a radio unit (RU) including a radio transceiver (TRX), i.e., a transmitter (Tx) and a receiver (Rx), one or more distributed units (DU) 105, which can be used for so-called layer 1 (LI) processing and real-time layer 2 (L2) processing, and a central unit (CU) 108 (also known as a centralized unit), which can be used for non-real-time L2 and layer 3 (L3) processing. The CU 108 can be connected to the one or more DUs 105, e.g., via an Fl interface. Such an embodiment of an access node can enable centralization of the CU with respect to the cell site and the DUs, which can be more distributed, and can even remain at the cell site. The CU and the DU together can also be referred to as a baseband or baseband unit (BBU). The CU and the DU can also be included in a radio access point (RAP).

[0058] The CU 108 can be a logical node that hosts the radio resource control (RRC), service data adaptation protocol (SDAP), and / or packet data convergence protocol (PDCP) of the NR protocol stack for the access node. The DU 105 can be a logical node that hosts the radio link control (RLC), medium access control (MAC), and / or physical (PHY) layer of the NR protocol stack for the access node. Operation of the DU can be controlled at least in part by the CU. It should also be understood that the distribution of functions between the DU 105 and the CU 108 can vary depending on implementation. The CU can include a control plane (CU-CP), which can be a logical node that hosts the control plane portion of the RRC and PDCP protocols of the NR protocol stack for the access node. The CU can also include a user plane (CU-UP), which can be a logical node that hosts the user plane portion of the PDCP protocol and the SDAP protocol of the CU for the access node.

[0059] The cloud computing system can also be used to provide the CU 108 and / or the DU 105. The CU provided by the cloud computing system can be referred to as a virtualized CU (vCU). In addition to the vCU, there can also be a virtualized DU (vDU) provided by the cloud computing system. Further, there can also be a combination in which the DU can be implemented on a so-called bare metal solution, such as an application-specific integrated circuit (ASIC) or customer-specific standard product (CSSP) system on a chip (SoC).

[0060] By utilizing network function virtualization (NFV) and software-defined networking (SDN), edge clouds can be introduced into the access network (e.g., RAN). Using edge clouds can mean that at least a portion of the operations of the access node are to be executed in a computing system that is operably coupled to a remote radio head (RRH) or a radio unit (RU) at the access node. It can also be that the operations of the access node are executed on a distributed computing system that is located at the access node or on a cloud computing system. The application of cloud-RAN architectures enables RAN real-time functions to be executed at the access network (e.g., in the DU 105) and non-real-time functions to be executed in a centralized manner (e.g., in the CU 108).

[0061] It should also be understood that the distribution of functions between the core network operations and the access node operations can be different, or even non-existent, in future wireless communication networks compared to LTE or 5G. Some other technological advancements that can be used include big data and all-IP, which can change the way wireless communication networks are constructed and managed. A 5G (or New Radio, NR) wireless communication network can support multiple hierarchies in which a multi-access edge computing (MEC) server can be placed between the core network 110 and the access node 104. It should be understood that MEC can also be applied in LTE wireless communication networks.

[0062] A 5G wireless communication network (“5G network”) can also include non-terrestrial communication networks, such as satellite communication networks, to enhance or complement the coverage of the 5G radio access network. For example, satellite communication can support data transmission between the 5G radio access network and the core network, thereby enabling a wider network coverage. Possible use cases can be to provide service continuity for machine-to-machine (M2M) or Internet of Things (IoT) devices or for passengers on board vehicles, or to ensure service availability for critical communications and future railway / maritime / aeronautical communications. Satellite communication can utilize a geostationary earth orbit (GEO) satellite system, but also a low earth orbit (LEO) satellite system, in particular a mega-constellation (a system in which several hundreds of (nano)satellites are deployed). A given satellite 106 in a mega-constellation can cover several satellite-enabled network entities that create terrestrial cells. The terrestrial cells can be created by terrestrial relay access nodes, or by access nodes 104 located in the ground or in a satellite.

[0063] It is clear to the person skilled in the art that, Figure 1 The illustrated access nodes 104 are merely examples of a part of an access network (e.g. a radio access network), and in practice, the access network can comprise multiple access nodes, the UEs 100, 102 can access multiple radio cells, and the access network can also comprise other apparatuses, such as physical layer relay access nodes or other entities. At least one of the access nodes can be a home eNodeB or a home gNodeB. A home gNodeB or a home eNodeB is a kind of access node that can be used to provide indoor coverage within a home, an office, or other indoor environment.

[0064] Furthermore, in the geographical area of an access network (e.g. a radio access network), multiple radio cells of different kinds can be provided, as well as multiple radio cells. A radio cell can be a macro cell (or umbrella cell), which can be a sizeable cell of up to tens of kilometers in diameter, or a smaller cell, such as a micro cell, a femto cell, or a pico cell. Figure 1 The access node(s) can provide any kind of these cells. A cellular radio network can be implemented as a multi-tiered access network comprising several kinds of radio cells. In a multi-tiered access network, one access node can provide one or more kinds of radio cells, and thus providing such a multi-tiered access network can require multiple access nodes.

[0065] To meet the need for improving the performance of the access network, the concept of a “plug-and-play” access node can be introduced. In addition to a home eNodeB or a home gNodeB, an access network capable of using “plug-and-play” access nodes can also include a home nodeB gateway or HNB-GW Figure 1A HNB-GW (not shown) can be installed within an operator's access network can aggregate traffic from a large number of home eNodeBs or home gNodeBs back to the operator's core network.

[0066] 6G wireless communication networks are expected to employ flexible, decentralized, and / or distributed computing systems and architectures and ubiquitous computing, with mobile edge computing, artificial intelligence, short packet communications, and blockchain technologies at its foundation, enabling local spectrum licensing, spectrum sharing, infrastructure sharing, and intelligent and automated management. Key features of 6G can include intelligent interconnection management and control functions, programmability, integrated sensing and communications, reduced energy footprints, trustworthy infrastructure, scalability, and affordability. In addition to this, 6G is targeting new use cases, including integration of positioning and sensing capabilities into the system definition to unify user experiences for the physical and digital worlds.

[0067] In NR Release 17 (Rel-17), the Third Generation Partnership Project (3GPP) introduced low-complexity, energy-efficient UEs, referred to as Reduced Capability (RedCap) devices. RedCap devices can also be referred to as RedCap UEs, NR-Lite devices, or NR-Light devices.

[0068] For example, RedCap devices can have the following characteristics: reduced number of transmit and / or receive antennas, reduced bandwidth (e.g., 20 MHz in frequency range 1 and 100 MHz in frequency range 2), half-duplex frequency division duplex (FDD), and / or relaxed processing capabilities compared to non-RedCap UEs.

[0069] Power saving and battery life extension are some of the main targets for RedCap devices. This can be achieved through several techniques, such as reduced physical downlink control channel (PDCCH) monitoring achieved through a reduced number of blind decodes and control channel element (CCE) limitation, extended discontinuous reception (DRX) for RRC inactive and / or idle states, and / or relaxed radio resource management (RRM) measurement for fixed devices.

[0070] An industrial wireless sensor is one example of a RedCap device. It can be desirable to connect the industrial wireless sensor to a 5G radio access network and core network to improve flexibility, increase productivity and efficiency, and improve operational safety. The industrial wireless sensor can include, for example, a pressure sensor, a humidity sensor, a thermometer, a motion sensor, and / or an accelerometer, among others. For the industrial wireless sensor use case, a RedCap device can have the following requirements: a communication service availability of at least 99.99%, an end-to-end latency of less than 100 ms, a reference bit rate of less than 2 Mbps (which can be asymmetric, e.g., UL heavy traffic), and devices are expected to be mostly stationary. For safety-related sensors, the latency requirement can be more stringent, e.g., 5-10 ms.

[0071] A video surveillance camera is another example of a RedCap device. For example, deploying surveillance cameras can be beneficial for smart city use cases as well as for factories and industries in order to more efficiently monitor and control city or factory resources. The following requirements can apply for video surveillance use cases: a reference economic video bit rate of 2-4 Mbps, a latency of less than 500 ms, and a reliability of at least 99%-99.9%. High-end video applications (e.g., for agriculture) can require a video bit rate of 7.5-25 Mbps. It should be noted that the traffic pattern can be dominated by UL transmissions.

[0072] A wearable device, such as a smartwatch, a ring, an electronic health-related device, a personal protective equipment, and / or a medical monitoring device, is another example of a RedCap device. The following requirements can apply for wearable devices: a reference bit rate for smart wearable applications can be 5-50 Mbps in the DL and 2-5 Mbps in the UL, and the peak bit rate of the device can be higher, e.g., up to 150 Mbps for the DL and up to 50 Mbps for the UL. In addition, the battery of the wearable device should last for several days (e.g., up to 1-2 weeks).

[0073] Smart wearable devices are becoming more useful due to the mobility of humans, as they can collect and emit data while on the move and accordingly receive information from the network, which helps make more informed decisions.

[0074] In NR Release 18 (Rel-18), 3GPP is specifying further device complexity reduction for RedCap devices in frequency range 1 (FR1). The goal is to introduce a low-tier device between IoT and Rel-17 RedCap devices. The peak data rate supported by Rel-18 RedCap devices is expected to be around 10 Mbps.

[0075] For example, further reduction in complexity of Rel-18 RedCap devices in FR1 can involve a reduction in UE baseband (BB) bandwidth, such that 5MHz BB bandwidth is dedicated for physical downlink shared channel (PDSCH) (for both unicast and broadcast) and physical uplink shared channel (PUSCH), with a radio frequency (RF) bandwidth of 20MHz for both UL and DL. Other physical channels and signals are still allowed to use bandwidth parts (BWPs) of up to 20MHz maximum RF+BB bandwidth.

[0076] Further, further reduction in complexity of Rel-18 RedCap devices in FR1 can involve a reduction in UE peak data rate, support for both 15kHz subcarrier spacing (SCS) and 30kHz SCS, and defining at most one target Rel-18 RedCap device type for further reduction in UE complexity. The current UE capability framework can be used, and changes to capability signaling can only be specified if necessary. By default, all UE capabilities applicable to Rel-17 RedCap devices can be applicable to Rel-18 RedCap devices unless specified otherwise.

[0077] Figure 2 A discontinuous reception (DRX) cycle 200 is illustrated. The purpose of the DRX mechanism is to provide efficient UE power saving, and thereby optimize UE battery life. By applying a received DRX configuration, the UE is allowed to enter a sleep mode 202 (with RF module turned off) after a certain period of data inactivity, and periodically wake up during an ON-duration 201 to perform eventual data reception or initiate data transmission. In other words, the power consumption of the UE can be reduced during the sleep mode 202. DRX operation is applicable to UEs in RRC connected state (using C-DRX configuration), as well as UEs in RRC idle or inactive state (through paging configuration). The C-DRX configuration can include, for example, the length of the DRX cycle 200 (short cycle and / or long cycle), the length of the ON-duration 201 for DL channel monitoring, and an inactivity timer. The network (e.g., gNB) can provide the DRX configuration to the UE via a dedicated RRC reconfiguration message (e.g., during handover) or in a system information block type 2 (SIB2) broadcast by the gNB (during initial attach). If there is no data activity, a long DRX cycle can be applied. In case of periodic DL data arrival, a short DRX cycle and multiple DRX cycles can be applied.

[0078] Positioning can be a process that estimates a location (e.g., a geographic location) of a UE. In this document, a UE to be positioned can be referred to as a target UE. The location of the target UE can be estimated in an absolute way (in case of absolute positioning) or in a relative way (in case of relative positioning). Absolute positioning refers to estimating the location of the target UE in two-dimensional or three-dimensional geographic coordinates (e.g., latitude, longitude, and / or altitude) within a coordinate system. Relative positioning refers to estimating the location of the target UE relative to one or more network nodes or relative to one or more other UEs.

[0079] For example, a positioning technique used in 5G NR can be based on at least one of: time difference of arrival (TDoA), time of arrival (TOA), time of departure (TOD), round-trip time (RTT), angle of departure (AoD), angle of arrival (AoA), and / or carrier phase.

[0080] TOA is the time a signal takes to travel from a base station to a UE. The UE measures the time of arrival of a signal from a single base station. Given that the propagation speed of the signal is known, this information can be used to calculate the distance between the UE and the base station.

[0081] TDoA is the difference in the time of arrival of signals from two different base stations. The UE can measure the difference in the time of arrival of signals from two different base stations. This information can be used to calculate the location of the UE.

[0082] To obtain positioning measurements in the DL, positioning reference signals (PRS) can be transmitted from one or more network nodes (e.g., base stations such as gNBs) of known locations and can be measured by the UE. To obtain positioning measurements in the UL, sounding reference signals (SRS) for positioning can be transmitted by the UE and can be measured by one or more network nodes (e.g., gNBs) of known locations. Positioning measurements can be measured in the physical layer. Depending on DL or UL, the baseband modem of the UE or the baseband modem of the gNB can support the positioning measurements using PRS or SRS.

[0083] In network-based positioning, the location of the target UE is estimated by a network entity (e.g., a gNB or an LMF). For network-based positioning, the target UE can report information to the network entity to enable estimation of the location of the target UE.

[0084] In UE-based positioning, the location of the target UE is estimated by the target UE.

[0085] SideLink (SL) positioning refers to a method of positioning in which a target UE utilizes a sidelink (i.e., a direct device-to-device link) to position itself in an absolute manner (in case of absolute positioning) or in a relative manner (in case of relative positioning). SL positioning can be beneficial for (but not limited to) the following use cases: public safety, vehicle-to-everything (V2X), and industrial Internet of Things (IIoT).

[0086] SL positioning can be based on transmission of a sidelink positioning reference signal (SL PRS) by multiple anchor UEs (e.g., at least three anchor UEs), where the SL PRS is received and measured by the target UE to enable positioning of the target UE (e.g., using SL TDoA techniques) within certain latency and accuracy requirements of the corresponding SL positioning session. Alternatively or additionally, the target UE can transmit SL PRS for reception and measurement by anchor UEs. The SL PRS exchange between the target UE and anchor UEs can be used for SL RTT-based positioning techniques, for example.

[0087] Target positioning accuracy requirements for RedCap devices in commercial use cases can be defined as follows: horizontal position accuracy (< 3 m) for 90% of UEs, and vertical position accuracy (< 3 m) for 90% of user equipment.

[0088] Target positioning accuracy requirements for RedCap devices for IIoT use cases can be defined as follows: horizontal position accuracy (< 1 m) for 90% of UEs, and vertical position accuracy (< 3 m) for 90% of UEs.

[0089] As mentioned above, RedCap devices are bandwidth-limited devices. However, for the (time-based) positioning techniques defined for NR Rel-16 and NR Rel-17, the accuracy of the positioning is proportional to the bandwidth of the PRS or SRS.

[0090] Frequency hopping is one possible solution to address the RedCap positioning bandwidth limitation.

[0091] Figure 3An example of a solution for an overlapping frequency hopping positioning measurement technique with phase compensation is illustrated. To increase audibility, increase correlation properties and improve interference avoidance properties, the PRS sequence 300 can be spread over time and frequency domain. This can be referred to as interleaved PRS. In other words, the gNB can transmit a wideband PRS 300 during all hops 301, 302, 303, 304, 305, but the UE (e.g., RedCap device) can receive only a small portion of the PRS at a time. These frequency hops 301, 302, 303, 304, 305 collected by the UE can also be referred to herein as PRS bins or frequency bins. For this, various configuration parameters of the PRS can be defined (e.g., comb size, repetition factor, periodicity, bandwidth factor, etc.). The receiver (i.e., the UE) can perform phase estimation and compensation on every two adjacent hops. The UE can aggregate the PRS bins 301, 302, 303, 304, 305 into an aggregated frequency band 306. The final positioning result can be obtained by exploiting the “wideband” positioning reference signal 306 stitched from the positioning reference signals from several consecutive hops. For example, the UE can estimate the time of arrival (TOA) by using the aggregated frequency band 306. However, there are challenges in how to coordinate the PRS with other signaling (e.g., DRX).

[0092] Figure 4 An example of misalignment between PRS and DRX is illustrated. The DRX cycle applied by the UE (e.g., RedCap device) and the DL PRS configured by the LMF are independent procedures. As shown, these independent procedures can result in misalignment between PRS transmission and DRX occasions, resulting in poor positioning measurements. Figure 4 In the example shown, the UE can detect PRS 403 and PRS 406 transmitted during the on duration of the DRX cycle. However, in this example, the UE can miss other PRS 401, 402, 404, 405 transmitted while the UE is asleep according to the DRX cycle. Figure 4

[0093] Figure 4 One possible solution to the misalignment shown can be to force the UE to wake up for the duration of the PRS transmission occasion to perform PRS measurements. However, this would increase the power consumption of the UE and thus also violate the goal of the DRX cycle introduced for RedCap devices.

[0094] On the other hand, if the UE does not wake up for the PRS transmission occasion, the UE cannot perform PRS measurements at the corresponding PRS transmission occasion, which can result in a positioning failure. More specifically, if a frequency hopping positioning measurement technique (e.g., as shown) is applied, the UE can not be able to receive all PRS bins due to its DRX cycle. Figure 3 ​​

[0095] Another possible cause of missing PRS intervals, in addition to DRX cycle mismatch, can be PRS priority with respect to another channel. For example, during PRS hop 1, if there is another channel (e.g., data) with higher priority, PRS hop 1 will not be received.

[0096] Some problems that can be encountered due to one or more missed PRS intervals are shown in Figure 5A , Figure 5B and Figure 5C .

[0097] In Figure 5A , the first PRS interval 501 is missed. In this case, phase compensation between the received PRS intervals 502, 503, 504, 505 is possible due to the overlap between the PRS intervals.

[0098] In Figure 5B , the last PRS interval 505 is missed. In this case, phase compensation between the received PRS intervals 501, 502, 503, 504 is possible due to the overlap between the PRS intervals.

[0099] In Figure 5C , the middle PRS interval 503 is missed. In this case, phase compensation between the received PRS intervals 501, 502, 504, 505 is not possible due to no overlap between the first two intervals 501, 502 and the last two intervals 504, 505. This results in phase discontinuity, which is highlighted at 511 and 512 in Figure 5C using different shading patterns.

[0100] Therefore, in order to effectively utilize or process partially received PRS intervals (e.g., as shown in Figure 5A , Figure 5B or Figure 5C ) and improve positioning accuracy, a new positioning procedure needs to be defined for frequency hopping positioning measurement techniques between the LMF and the UE (e.g., RedCap device). In other words, a method is needed to receive the minimum PRS sequence needed or to efficiently perform UE positioning within the required accuracy using partially received PRS intervals, as the UE can not be able to receive all N subbands or intervals within the DRX cycle. That is, the network can need to make additional decisions based on information sent by the UE during the positioning measurements to improve the integrity and / or accuracy of the positioning.

[0101] However, some example embodiments are described below using principles and terminology of 5G radio access technology without limiting the example embodiments to 5G radio access technology.

[0102] Some example embodiments can provide solutions to overcome issues with frequency hopping positioning measurement techniques in Figure 4 , Figure 5A , Figure 5B and Figure 5C .

[0103] Some example embodiments can provide LMF-based procedures to handle missed PRS intervals while using frequency hopping positioning measurement techniques.

[0104] In some cases (e.g., UE environment is static, no fading, no mobility, strong line-of-sight, etc.), the LMF can reuse any missed PRS intervals from earlier successful frequency hopping receptions to increase the received PRS bandwidth, thereby improving the TOA estimation accuracy.

[0105] Example embodiments described herein can reduce the UE’s continuous monitoring of PRS. In addition, example embodiments can reduce the computational load associated with positioning-related parameters at the UE side and transfer it to the LMF side while reducing the UE’s power consumption. Furthermore, example embodiments can allow the LMF to adaptively adjust the channel characteristics and related thresholds to improve the positioning accuracy.

[0106] Figure 6A and Figure 6B FIG. 1 illustrates an example of replacing missed PRS intervals with previously successfully received PRS intervals in previous time occasions.

[0107] In Figure 6A , in a first set of frequency hops 610 during a frequency hopping time occasion O(t-2), the UE has successfully received PRS1 interval 611, PRS2 interval 612, PRS3 interval 613, and PRS4 interval 614.

[0108] In a second set of frequency hops 620 during a frequency hopping time occasion O(t-1), the UE has successfully received PRS2 interval 622, PRS3 interval 623, PRS4 interval 624, and PRS5 interval 625.

[0109] In a third set of frequency hops 630 during a frequency hopping time occasion O(t), the UE has successfully received PRS2 interval 632, PRS3 interval 633, and PRS4 interval 634. However, during the frequency hopping time occasion O(t), the UE missed PRS1 interval and PRS5 interval of the third set of frequency hops 630.

[0110] Based on channel conditions (e.g., UE mobility environment, etc.), the LMF can decide whether to reuse PRS5 intervals 625 from the earlier successful frequency hopping reception of PRS1 intervals 611 (hopping occasion O(t-2)) and hopping time occasion O(t-1) for positioning measurements (e.g., for TOA estimation, as greater bandwidth improves accuracy). In other words, as shown in Figure 6B the missed PRS1 intervals of the third frequency hopping set 630 can be replaced with the successfully received PRS1 intervals 611 from the first frequency hopping set 610, and the missed PRS5 intervals of the third frequency hopping set 630 can be replaced with the successfully received PRS5 intervals 625 from the second frequency hopping set 610. This results in wideband PRS in occasion O(t).

[0111] Figure 7 FIGURE 1 illustrates a signal flow diagram in which positioning measurements are performed using a frequency hopping configuration, according to an example embodiment.

[0112] Reference is made to Figure 7 At 701, at least one RAN node 104 (e.g., gNB) transmits a plurality of positioning reference signals of a first frequency hopping set at a time occasion O(t-n). Herein, the positioning reference signals can also be referred to as PRS intervals or frequency intervals or frequency hops. The UE 100 receives the plurality of positioning reference signals (PRS intervals) of the first frequency hopping set. In other words, in this case, the UE does not miss any PRS intervals during the positioning measurements of PRS using frequency hopping. The UE 100 can be a reduced capability (RedCap) device or any other type of UE.

[0113] At 702, the UE 100 obtains raw channel estimates of the plurality of received positioning reference signals (PRS intervals) of the first frequency hopping set. For example, the UE 100 can obtain a raw channel estimate for each received PRS interval. Based on the raw channel estimates, the UE 100 determines timing measurements (such as time of arrival (TOA) estimates or time difference of arrival (TDoA) estimates), and one or more channel characteristics of the plurality of received positioning reference signals (PRS intervals) of the first frequency hopping set. In other words, the UE 100 extracts one or more channel characteristics during the measurements of each PRS interval. The UE 100 can determine the timing measurements by leveraging or aggregating the plurality of positioning reference signals (i.e., all received hops), resulting in wideband PRS. Alternatively or additionally, the UE 100 can determine one or more other positioning related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0114] For example, the one or more channel characteristics can comprise at least one of: a channel impulse response (CIR), a channel flatness probability (CFP), a reference signal received power (RSRP), a reference signal received quality (RSRQ), or a power delay profile (PDP) having a certain PDP length (the PDP length is configured by the LMF). The CFP, RSRP, and RSRQ can be expressed as a value. The CIR is a complex function that describes how a given channel modifies a signal that is transmitted through it. The PDP is a function that provides information about how the power of a received signal is distributed as a function of time delay.

[0115] The term “raw channel estimate” refers to an initial estimate of these channel characteristics before any quantization, baseband oversampling, or other signal processing is applied. In other words, the raw channel estimate is a direct measurement or estimate of the channel response. The raw channel estimate can be obtained using various techniques, such as pilot symbols, training sequences, or other known signal features.

[0116] For example, let H represent the channel, and X represent the PRS symbols. Then, the received signal Y = HX + noise. The raw channel estimate is Y / X = H + noise / X. Depending on the bandwidth, there can be PRS symbols X1, X2, X3, X4, X5, …, Xn. For example, a first PRS interval (PRS interval 1) can comprise [X1 X2 X3 X4], and a second PRS interval (PRS interval 2) can comprise [X4 X5 X6 X7]. Then, the TOA can be estimated from the (aggregated) raw channel estimates, and one or more channel characteristics can be derived for each raw channel estimate.

[0117] At 703, the UE 100 transmits information to a location management entity, such as the LMF 112, indicating at least timing measurements and / or AoA of a plurality of received positioning reference signals of the first set of frequency hops and one or more channel characteristics. The UE 100 can transmit the information to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives the information.

[0118] The information can also indicate one or more timestamps associated with the one or more channel characteristics, and an identifier of each received PRS interval. In other words, the UE 100 can transmit the estimated one or more channel characteristics of each received PRS interval to the LMF 112 along with a timestamp.

[0119] At 704, the LMF 112 stores or saves one or more channel properties of each received PRS interval at the time occasion O(t-n) in the at least one memory along with the time stamp, along with the PRS interval ID, for a certain memory window length.

[0120] At 705, the at least one RAN node 104 (e.g., gNB) transmits a plurality of positioning reference signals (PRS intervals) of a second frequency hopping set at a time occasion O(t) (i.e., the second frequency hopping set is transmitted at a later time compared to the first frequency hopping set). The UE 100 receives one or more positioning reference signals (PRS intervals) of the second frequency hopping set.

[0121] At 706, the UE 100 determines that one or more positioning reference signals (PRS intervals) are missed in the second frequency hopping set, and the UE 100 determines one or more identifiers of the one or more missed positioning reference signals of the second frequency hopping set (i.e., an identifier for each missed PRS interval). The UE can be preconfigured with a DL PRS configuration that indicates the PRS intervals that the UE should receive, and thus the UE can determine the one or more missed positioning reference signals (PRS intervals) based on the DL PRS configuration.

[0122] For example, if the UE 100 is sleeping when the PRS interval(s) are transmitted, the UE 100 can miss one or more PRS intervals due to its DRX cycle. As another example, if the priority of the PRS is less than another channel (e.g., data), the UE can miss one or more PRS intervals even if it is in an awake state.

[0123] At 707, the UE 100 obtains raw channel estimates for one or more received positioning reference signals (PRS intervals) of the second set of frequency hops. For example, the UE 100 can obtain a raw channel estimate for each received PRS interval. Based on the raw channel estimates, the UE 100 determines timing measurements (such as TOA estimates or TDoA estimates), and one or more channel characteristics for one or more received positioning reference signals (PRS intervals) of the second set of frequency hops. In other words, the UE 100 extracts one or more channel characteristics during the measurement of each received PRS interval. The UE 100 can determine the timing measurements by utilizing or aggregating one or more received positioning reference signals (i.e., all received hops), resulting in a wideband PRS. It should be noted that the one or more missed positioning reference signals (missed PRS intervals) are excluded from the timing measurements. Alternatively or additionally, the UE 100 can determine one or more other positioning-related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0124] At 708, the UE 100 sends information to the LMF 112 indicating the timing measurements and / or AoA for one or more received positioning reference signals (PRS intervals) of the second set of frequency hops (excluding the one or more missed PRS intervals), the one or more channel characteristics for one or more received positioning reference signals (PRS intervals) of the second set of frequency hops, and one or more identifiers for the one or more missed positioning reference signals of the second set of frequency hops (i.e., an identifier for each missed PRS interval). The UE 100 can send the information to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives the information. The LMF 112 can store or save the information in at least one memory.

[0125] The information can also indicate one or more timestamps associated with the one or more channel characteristics, and an identifier for each received PRS interval of the second set of frequency hops. In other words, the UE 100 can send to the LMF 112 the estimated one or more channel characteristics for each received PRS interval, and a timestamp.

[0126] Using this signaling, the UE 100 queries the LMF 112 for the best way to handle one or more missed PRS intervals. The network (e.g., LMF 112) has more processing power and memory than the UE 100, so the available information, identifiers, and timestamps regarding the extracted channel characteristics of the PRS intervals can be used to make a decision about one or more missed PRS intervals. Based on the information collected about the channel characteristics of the received PRS intervals between occasion O(t) and occasion O(t-n), the network (e.g., LMF 112) can propose different options, including retransmission of one or more missed PRS intervals, or replacing one or more missed PRS intervals with a previously received PRS interval (e.g., from occasion O(t-n)).

[0127] At 709, the LMF 112 determines whether to replace one or more missed PRS intervals with one or more previous PRS intervals from occasion O(t-n). For example, the LMF can compare the channel characteristics between time occasions O(t) and O(t-n), or use a learning-based algorithm (such as an artificial intelligence or machine learning algorithm) to decide whether a previous time instance of a given PRS interval can be utilized in case of a missed PRS interval. If yes, and with a high probability, the LMF 112 can signal the UE 100 to use a previous PRS interval instead of the missed PRS interval, and send back the estimated positioning measurements (e.g., TOA).

[0128] As another option, the LMF 112 can instruct the UE 100 to use a weighted average of previous correctly received PRS intervals corresponding to the missed PRS interval(s). For example, if PRS1 interval is missed at occasion O(t), the missed PRS1 interval can be replaced with a weighted average of the PRS1 intervals correctly received at occasions O(t-1), O(t-2), and O(t-3).

[0129] As an example (see Figure 6A), the LMF can compare one or more channel properties of the received PRS2 interval 632 of occasion O(t) and the received PRS2 interval 622 of occasion O(t-1) to determine whether to replace the missed PRS5 interval of occasion O(t) with the received PRS5 interval 625 of occasion O(t-1). If the channel properties between the time occasions (e.g., between PRS2 interval 632 and PRS2 interval 622) are similar, the LMF can decide to replace the missed PRS interval(s) with the previously received PRS interval(s). The identifier(s) of the one or more previously received PRS intervals to use for replacement can correspond to the identifier(s) of the missed PRS interval(s) (e.g., PRS5 interval 625 of occasion O(t-1) can be used to replace the corresponding missed PRS5 interval of occasion O(t)).

[0130] In this way, based at least on the one or more channel properties of the one or more received positioning reference signals of the second set of frequency hops, and the one or more corresponding channel properties of the one or more corresponding positioning reference signals received (by the UE 100) in the first set of frequency hops, the one or more missed positioning reference signals (PRS intervals) can be compensated for by utilizing one or more previous positioning reference signals (PRS intervals) from the first set of frequency hops (i.e., the previous set of frequency hops).

[0131] Reference is made below to Figure 10 Some additional examples are described for determining whether to replace one or more missed PRS intervals.

[0132] At 710, based on determining to replace the one or more missed positioning reference signals (PRS intervals), the LMF 112 sends an indication to the UE 100 that indicates that the one or more missed positioning reference signals (PRS intervals) of the second set of frequency hops are replaced with one or more previous positioning reference signals (PRS intervals) from the first set of frequency hops, and based on the replacement, to send new timing measurements to the LMF 112. In other words, the LMF 112 indicates to the UE 100 its decision to replace the one or more missed PRS intervals with one or more previous PRS intervals. The LMF 112 can send the indication to the UE 100 via the RAN node 104 (e.g., gNB).

[0133] At 711, the UE 100 replaces, based on the indication, the one or more missed positioning reference signals (PRS intervals) with the one or more previous positioning reference signals (PRS intervals) by using the original channel estimates (obtained at 702) of the one or more previous positioning reference signals (PRS intervals). The replacement can represent, for example, combining the original channel estimates of the one or more previous positioning reference signals (PRS intervals) from the occasion O(t-n) with the original channel estimates of the one or more received positioning reference signals (PRS intervals) of the occasion O(t).

[0134] At 712, the UE 100 determines, based on the replacement, timing measurements, such as TOA estimates or TDoA estimates, associated with the one or more received positioning reference signals (PRS intervals) of the second frequency-hopping set (occasion O(t)) and the one or more previous positioning reference signals (PRS intervals) of the first frequency-hopping set (occasion O(t-n)) used to replace the one or more missed positioning reference signals (PRS intervals) of the second frequency-hopping set. In other words, the UE 100 can obtain the timing measurements by utilizing or aggregating the one or more received positioning reference signals (PRS intervals) of the second frequency-hopping set and the one or more previous positioning reference signals (PRS intervals) of the first frequency-hopping set, thereby resulting in a wideband PRS. Alternatively or additionally, the UE 100 can also determine one or more other positioning-related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0135] At 713, the UE 100 sends or reports, to the LMF 112, the timing measurements and / or AoA associated with the one or more received positioning reference signals (PRS intervals) of the second frequency-hopping set and the one or more previous positioning reference signals (PRS intervals) of the first frequency-hopping set. The UE 100 can send the timing measurements to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives, from the UE 100, the timing measurements associated with the one or more received positioning reference signals of the second frequency-hopping set and the one or more previous positioning reference signals of the first frequency-hopping set based on sending the indication.

[0136] At 714, the LMF 112 estimates a position (i.e., location) of the UE 100 based at least in part on timing measurements (e.g., TOA estimates or TDoA estimates) and / or AoA associated with one or more received positioning reference signals (PRS intervals) of the second set of frequency hops and one or more previous positioning reference signals (PRS intervals) from the first set of frequency hops. For example, a TOA estimate can be used to estimate a distance between the UE 100 and at least one RAN node 104. The location of the at least one RAN node 104 can be known to the LMF 112, and thus the LMF can estimate the location of the UE 100 based on the distance between the UE 100 and the at least one RAN node 104.

[0137] For a two-dimensional position estimate of the UE 100, TOA estimates of at least two RAN nodes (e.g., gNBs) can be needed. For a three-dimensional position (x, y, z coordinates) of the UE 100, TOA estimates of at least three RAN nodes (e.g., gNBs) can be needed by the LMF.

[0138] Figure 8 A signal flow diagram is illustrated in which positioning measurements are performed using a frequency hopping configuration, according to an example embodiment. In this example embodiment, if the LMF determines that reusing PRS intervals from a previous occasion to replace missed PRS intervals is not feasible, the LMF configures the gNB and the UE for retransmission of the missed PRS intervals.

[0139] Reference Figure 8 At 801, at least one RAN node 104 (e.g., a gNB) transmits a plurality of positioning reference signals of a first set of frequency hops at a time occasion O(t-n). Herein, a positioning reference signal can also be referred to as a PRS interval or a frequency interval or a frequency hop. The UE 100 receives the plurality of positioning reference signals (PRS intervals) of the first set of frequency hops. In other words, in this case, the UE does not miss any PRS intervals during the positioning measurements of the PRS using frequency hopping. The UE 100 can be a reduced capability (RedCap) device or any other type of UE.

[0140] At 802, the UE 100 obtains raw channel estimates for a plurality of received positioning reference signals (PRS intervals) of the first set of frequency hops. In other words, the UE 100 can obtain a raw channel estimate for each received PRS interval. Based on the raw channel estimates, the UE 100 determines timing measurements (such as time of arrival (TOA) estimates or time difference of arrival (TDoA) estimates), and one or more channel characteristics for the plurality of received positioning reference signals (PRS intervals) of the first set of frequency hops. In other words, the UE 100 extracts one or more channel characteristics during the measurement of each PRS interval. The UE 100 can determine the timing measurements by utilizing or aggregating the plurality of positioning reference signals (i.e., all received hops), resulting in a wideband PRS. Alternatively or additionally, the UE 100 can determine one or more other positioning-related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0141] For example, the one or more channel characteristics can include at least one of: a channel impulse response (CIR), a channel flatness probability (CFP), a reference signal received power (RSRP), a reference signal received quality (RSRQ), or a power delay profile (PDP) having a certain PDP length (the PDP length is configured by the LMF).

[0142] At 803, the UE 100 sends information to a location management entity, such as the LMF 112, indicating at least the timing measurements and / or AoA for the plurality of received positioning reference signals of the first set of frequency hops, and the one or more channel characteristics. The UE 100 can send the information to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives the information.

[0143] The information can also indicate one or more timestamps associated with the one or more channel characteristics, and an identifier for each received PRS interval. In other words, the UE 100 can send the estimated one or more channel characteristics for each PRS interval to the LMF 112 along with a timestamp.

[0144] At 804, the LMF 112 stores or saves the one or more channel characteristics for each PRS interval of the time occasion O(t-n) in at least one memory along with the PRS interval ID and the timestamp for a certain memory window length.

[0145] At 805, the at least one RAN node 104 (e.g., gNB) transmits a plurality of positioning reference signals (PRS intervals) of a second frequency hopping set at a time occasion O(t) (i.e., the second frequency hopping set is transmitted at a later time compared to the first frequency hopping set). The UE 100 receives one or more positioning reference signals (PRS intervals) of the second frequency hopping set.

[0146] At 806, the UE 100 determines that one or more positioning reference signals (PRS intervals) are missed in the second frequency hopping set, and the UE 100 determines one or more identifiers of the one or more missed positioning reference signals of the second frequency hopping set (i.e., an identifier for each missed PRS interval). The UE can be preconfigured with a DL PRS configuration that indicates the PRS intervals that the UE should receive, and thus the UE can determine the one or more missed positioning reference signals (PRS intervals) based on the DL PRS configuration.

[0147] At 807, the UE 100 obtains raw channel estimates of the one or more received positioning reference signals (PRS intervals) of the second frequency hopping set. For example, the UE 100 can obtain a raw channel estimate for each received PRS interval. Based on the raw channel estimates, the UE 100 determines timing measurements (such as TOA estimates or TDoA estimates), and one or more channel characteristics of the one or more received positioning reference signals (PRS intervals) of the second frequency hopping set. In other words, the UE 100 extracts the one or more channel characteristics during the measurement of each received PRS interval. The UE 100 can determine a timing measurement estimate by utilizing or aggregating the one or more received positioning reference signals (i.e., all received hops), resulting in a wideband PRS. It should be noted that the one or more missed positioning reference signals (missed PRS intervals) are excluded from the timing measurement. Alternatively or additionally, the UE 100 can determine one or more other positioning-related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0148] At 808, the UE 100 sends information to the LMF 112 indicating timing measurements and / or AoA for one or more received positioning reference signals (PRS intervals) of the second set of frequency hops (excluding one or more missed PRS intervals), one or more channel characteristics for one or more received positioning reference signals (PRS intervals) of the second set of frequency hops, and one or more identifiers for one or more missed positioning reference signals of the second set of frequency hops (i.e., an identifier for each missed PRS interval). The UE 100 can send the information to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives the information. The LMF 112 can store or save the information in at least one memory.

[0149] The information can also indicate one or more timestamps associated with the one or more channel characteristics, and an identifier for each received PRS interval of the second set of frequency hops. In other words, the UE 100 can send to the LMF 112 the estimated one or more channel characteristics for each received PRS interval, and a timestamp.

[0150] At 809, the LMF 112 determines whether to replace the one or more missed PRS intervals with previous PRS intervals. For example, the LMF can compare channel characteristics between the time occasions O(t) and O(t-n), or use a learning-based algorithm (such as an artificial intelligence or machine learning algorithm) to decide whether a previous time instance of a given PRS interval can be utilized in case of a missed PRS interval. In this case, the LMF 112 determines that the one or more missed positioning reference signals (PRS intervals) do not need to be replaced with previous PRS intervals.

[0151] At 810, based on the determination that the one or more missed positioning reference signals (PRS intervals) do not need to be replaced, the LMF 112 sends an indication to the UE 100 indicating that retransmission of the one or more missed positioning reference signals (PRS intervals) is prepared. In other words, the LMF 112 indicates to the UE 100 its decision not to replace the one or more missed PRS intervals with one or more previous PRS intervals. The LMF 112 can send the indication to the UE 100 via the RAN node 104 (e.g., gNB).

[0152] At 811, the LMF 112 sends an indication to at least one RAN node 104 (e.g., gNB) indicating retransmission of the one or more missed positioning reference signals (PRS intervals). The timing of the retransmission can be matched to the DRX cycle of the UE 100, such that the retransmission occurs during an on-duration.

[0153] In other words, in this case, the one or more missed positioning reference signals can be compensated for by sending an indication to the UE 100 to prepare for retransmission of the one or more missed positioning reference signals, and having the at least one RAN node 104 retransmit the one or more missed positioning reference signals.

[0154] At 812, the at least one RAN node 104 (e.g., gNB) retransmits the one or more missed positioning reference signals (PRS intervals) at occasion O(t+n) (i.e., at a later time compared to the transmission of the second set of frequency hops). Based on the indication of 810, the UE 100 receives the retransmission of the one or more missed positioning reference signals (PRS intervals).

[0155] At 813, the UE 100 determines measurements, such as TOA estimates or TDoA estimates, associated with the one or more received positioning reference signals (PRS intervals) from occasion O(t) of the second set of frequency hops, and the retransmission of the one or more missed positioning reference signals (PRS intervals) from occasion O(t+n). In other words, the UE 100 can obtain timing measurements by utilizing or aggregating the one or more received positioning reference signals (PRS intervals) from occasion O(t) of the second set of frequency hops, and the retransmission of the one or more missed positioning reference signals (PRS intervals) from occasion O(t+n), resulting in a wideband PRS. Alternatively or additionally, the UE 100 can also determine one or more other positioning related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0156] At 814, the UE 100 sends or reports the timing measurements and / or AoA associated with the one or more received positioning reference signals (PRS intervals) from the second set of frequency hops, and the retransmission of the one or more missed positioning reference signals (PRS intervals) to the LMF 112. The UE 100 can send the timing measurements to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives the timing measurements from the UE 100.

[0157] At 815, the LMF 112 estimates a position (i.e., location) of the UE 100 based at least in part on timing measurements (e.g., TOA estimates or TDoA estimates) and / or AoA associated with one or more received positioning reference signals (PRS intervals) of the second set of frequency hops, and one or more missed retransmissions of the positioning reference signals (PRS intervals) (from occasion O(t+n)). For example, a TOA estimate can be used to estimate a distance between the UE 100 and the at least one RAN node 104. The location of the at least one RAN node 104 can be known by the LMF 112, and thus the LMF can estimate the location of the UE 100 based on the distance between the UE 100 and the at least one RAN node 104.

[0158] For a two-dimensional position estimate of the UE 100, TOA estimates of at least two RAN nodes (e.g., gNBs) can be needed. For a three-dimensional position (x, y, z coordinates) of the UE 100, TOA estimates of at least three RAN nodes (e.g., gNBs) can be needed by the LMF.

[0159] Figure 9 A signal flow diagram is illustrated in which positioning measurements are performed using a frequency hopping configuration, according to an example embodiment. In this example embodiment, the UE sends to the LMF its acquired received signals (i.e., raw channel estimates) instead of or in addition to PRS interval channel characteristics. In this approach, the UE can apply, for example, a compressive sensing technique to the raw channel estimates to reduce the payload size, and the LMF reconstructs or decompresses the signals (raw channel estimates) sent by the UE.

[0160] Reference Figure 9 At 901, the at least one RAN node 104 (e.g., gNB) transmits a plurality of positioning reference signals of a first set of frequency hops at a time occasion O(t-n). Herein, the positioning reference signals can also be referred to as PRS intervals or frequency intervals or frequency hops. The UE 100 receives the plurality of positioning reference signals (PRS intervals) of the first set of frequency hops. In other words, in this case, the UE does not miss any PRS intervals during the positioning measurements of the PRS using frequency hopping. The UE 100 can be a reduced capability (RedCap) device or any other type of UE.

[0161] At 902, the UE 100 obtains a raw channel estimate for each positioning reference signal of the plurality of received positioning reference signals (PRS intervals) of the first set of frequency hops. In other words, the UE 100 can obtain a raw channel estimate for each received PRS interval.

[0162] At 903, the UE 100 obtains compressed raw channel estimates for each positioning reference signal of the plurality of received positioning reference signals (PRS intervals) of the first set of frequency hops by compressing the raw channel estimates. In other words, the UE 100 can compress the raw channel estimates for each received PRS interval of the first set of frequency hops.

[0163] For example, the raw channel estimates can be compressed with compressive sensing techniques. Alternatively, any other compression technique can be used.

[0164] At 904, the UE 100 transmits the compressed raw channel estimates for the plurality of received positioning reference signals (PRS intervals) of the first set of frequency hops to the LMF 112. The UE 100 can transmit the compressed raw channel estimates to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives the compressed raw channel estimates for the plurality of received positioning reference signals (PRS intervals) of the first set of frequency hops from the UE 100.

[0165] The compressed raw channel estimates indicate one or more channel characteristics of the plurality of received positioning reference signals, which the LMF 112 can determine after decompressing the compressed raw channel estimates.

[0166] At 905, the LMF 112 obtains decompressed raw channel estimates for each positioning reference signal of the plurality of positioning reference signals (PRS intervals) of the first set of frequency hops by decompressing the compressed raw channel estimates.

[0167] The LMF 112 can store the decompressed raw channel estimates in at least one memory.

[0168] At 906, the LMF 112 determines timing measurements (such as TOA estimates or TDoA estimates) and one or more channel characteristics of the plurality of positioning reference signals (PRS intervals) of the first set of frequency hops based on the decompressed raw channel estimates of the plurality of positioning reference signals (PRS intervals) of the first set of frequency hops. The LMF 112 can determine the timing measurements by utilizing or aggregating the plurality of positioning reference signals (i.e., all received hops), resulting in a wideband PRS. Alternatively or additionally, the LMF can determine one or more other positioning-related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0169] For example, the one or more channel characteristics can include at least one of: channel impulse response (CIR), channel flatness probability (CFP), reference signal received power (RSRP), reference signal received quality (RSRQ), or power delay profile (PDP) with a certain PDP length (the PDP length is configured by the LMF).

[0170] At 907, the at least one RAN node 104 (e.g., gNB) transmits a plurality of positioning reference signals (PRS intervals) of a second frequency hopping set at a time occasion O(t) (i.e., the second frequency hopping set is transmitted at a later time compared to the first frequency hopping set). The UE 100 receives one or more positioning reference signals (PRS intervals) of the second frequency hopping set.

[0171] At 908, the UE 100 determines that one or more positioning reference signals (PRS intervals) are missed in the second frequency hopping set, and the UE 100 determines one or more identifiers of the one or more missed positioning reference signals of the second frequency hopping set (i.e., an identifier for each missed PRS interval). The UE can be preconfigured with a DL PRS configuration that indicates the PRS intervals that the UE should receive, and thus the UE can determine the one or more missed positioning reference signals (PRS intervals) based on the DL PRS configuration.

[0172] At 909, the UE 100 obtains raw channel estimates of the one or more received positioning reference signals (PRS intervals) of the second frequency hopping set. In other words, the UE 100 can obtain a raw channel estimate for each received PRS interval of the second frequency hopping set.

[0173] At 910, the UE 100 obtains compressed raw channel estimates of the one or more received positioning reference signals (PRS intervals) of the second frequency hopping set by compressing the raw channel estimates of the one or more received positioning reference signals (PRS intervals) of the second frequency hopping set. In other words, the UE 100 can compress the raw channel estimate for each received PRS interval of the second frequency hopping set.

[0174] At 911, the UE 100 transmits the compressed raw channel estimates of the one or more received positioning reference signals (PRS intervals) of the second frequency hopping set, and the one or more identifiers of the one or more missed positioning reference signals (PRS intervals) of the second frequency hopping set to the LMF 112. The UE 100 can transmit the compressed raw channel estimates, and the one or more identifiers to the LMF 112 via the RAN node 104 (e.g., gNB). The LMF 112 receives the compressed raw channel estimates of the one or more received positioning reference signals (PRS intervals) of the second frequency hopping set, and the one or more identifiers of the one or more missed positioning reference signals from the UE 100. The LMF 112 can store the received information in at least one memory.

[0175] At 912, the LMF 112 obtains decompressed raw channel estimates for each of the one or more positioning reference signals (PRS intervals) of the second set of frequency hops by decompressing compressed raw channel estimates for each of the one or more positioning reference signals (PRS intervals) of the second set of frequency hops. The LMF 112 can store the decompressed raw channel estimate(s) in at least one memory.

[0176] At 913, the LMF 112 determines one or more channel characteristics for each of the one or more positioning reference signals (PRS intervals) of the second set of frequency hops based on the decompressed raw channel estimates for each of the one or more positioning reference signals (PRS intervals) of the second set of frequency hops.

[0177] At 914, the LMF 112 compares channel characteristics of PRS intervals that were correctly received between occasion O(t) and occasion O(t-n) to one or more predefined thresholds. If the comparison satisfies one or more predefined conditions, the LMF can use one or more PRS intervals received in an earlier DRX cycle (occasion O(t-n)) to replace one or more missed PRS intervals of occasion O(t).

[0178] For example, the LMF 112 can determine a similarity measure (e.g., a difference or coherence time or dynamic time warping index) between one or more channel characteristics of the one or more received positioning reference signals (PRS intervals) of the second set of frequency hops and one or more corresponding channel characteristics of one or more corresponding positioning reference signals (PRS intervals) received in the first set of frequency hops (i.e., the previous set of frequency hops). The LMF 112 can then compare the similarity measure to one or more predefined thresholds to determine whether to compensate (e.g., replace) one or more missed positioning reference signals by utilizing one or more previous positioning reference signals from the first set of frequency hops.

[0179] Reference is made below to Figure 10 Some additional examples are described.

[0180] At 915, after determining to replace one or more missed positioning reference signals based on the comparison, the LMF 112 replaces the one or more missed positioning reference signals of the second set of frequency hops with one or more previous positioning reference signals from the first set of frequency hops by using the decompressed raw channel estimates (obtained at 905) of the one or more previous positioning reference signals.

[0181] At 916, the LMF 112 determines, based on the replacement, timing measurements, such as TOA estimates or TDoA estimates, associated with the one or more received positioning reference signals of the second set of frequency hops and the one or more previous positioning reference signals from the first set of frequency hops. The LMF 112 can obtain the timing measurements by utilizing or aggregating the one or more received positioning reference signals (PRS intervals) of the second set of frequency hops and the one or more previous positioning reference signals (PRS intervals) of the first set of frequency hops, resulting in a wideband PRS. Alternatively or additionally, the LMF can determine one or more other positioning-related measurements, such as angle of arrival (AoA), based on the aggregated PRS.

[0182] At 917, the LMF 112 estimates a position (i.e., location) of the UE 100 based at least in part on the timing measurements (e.g., TOA estimates or TDoA estimates) and / or AoA associated with the one or more received positioning reference signals (PRS intervals) of the second set of frequency hops and the one or more previous positioning reference signals (PRS intervals) from the first set of frequency hops. For example, the TOA estimates can be used to estimate a distance between the UE 100 and the at least one RAN node 104. The location of the at least one RAN node 104 can be known to the LMF 112, and thus the LMF can estimate the location of the UE 100 based on the distance between the UE 100 and the at least one RAN node 104.

[0183] For a two-dimensional position estimate of the UE 100, TOA estimates of at least two RAN nodes (e.g., gNBs) can be needed. For a three-dimensional position (x, y, z coordinates) of the UE 100, TOA estimates of at least three RAN nodes (e.g., gNBs) can be needed by the LMF.

[0184] It should be noted that the example embodiments are not limited to downlink positioning scenarios and they can also be applied to sidelink positioning scenarios. For example, in Figure 7 、 Figure 8 and Figure 9 , the gNB 104 can be replaced by another UE 102 which can transmit SL PRS intervals received by the UE 100.

[0185] Figure 10 FIGURE 13 illustrates a flowchart of an example embodiment of a method according to performed by the apparatus 1400, such as a location server, a location management function 112 of a core network 110, or any other location management entity.

[0186] In this example embodiment, the decision making entity (e.g., LMF) can consider one or more channel characteristics (defined for each received PRS interval and timestamp) as input parameters to the decision of whether to replace one or more missed PRS intervals (e.g., at 709 of FIG. 7, or at 809 of FIG. 8, or at 914 of FIG. 9). Figure 7 Figure 8 Figure 9

[0187] In block 1001, the LMF determines one or more similarity measures between the one or more channel characteristics of the one or more received positioning reference signals (from occasion O(t)) and one or more corresponding channel characteristics of one or more corresponding positioning reference signals received in one or more previous sets of frequency hops (from occasion O(t-n)).

[0188] For example, the one or more channel characteristics can include at least one of: a channel impulse response (CIR), a channel flatness probability (CFP), a reference signal received power (RSRP), a reference signal received quality (RSRQ), or a power delay profile (PDP) with a specific PDP length (PDP length is configured by the LMF).

[0189] The one or more similarity measures can include at least one of: a difference between the one or more channel characteristics of the one or more received positioning reference signals and the one or more corresponding channel characteristics of the one or more corresponding positioning reference signals received in the one or more previous sets of frequency hops, a coherence time between the one or more received positioning reference signals and the one or more corresponding positioning reference signals from the one or more previous sets of frequency hops, or a dynamic time warping index between the one or more received positioning reference signals and the one or more corresponding positioning reference signals from the one or more previous sets of frequency hops.

[0190] The coherence time (CT) and / or dynamic time warping (DTW) index can be used as additional similarity measures to identify a correlation factor between the current frequency hopping occasion O(t) and one or more previous occasions O(t-n) (to check whether the channel characteristics have changed significantly).

[0191] Coherence time is a term used in wireless communications to describe the duration of time for which a wireless channel can be considered “constant” or “stable.” A wireless channel is subject to various phenomena such as multipath propagation, fading, and Doppler shift due to the mobility of the transmitter, receiver, or surrounding objects. These factors can cause the channel properties to change over time. However, for a given period of time, if these changes are small, the channel can be considered “coherent” or “constant.” This period of time is referred to as the coherence time of the channel.

[0192] ​​​DTW is an algorithm for measuring similarity between two time series. In general, it can be used to compute the best match between two given sequences. Here, it can be used to measure the similarity between PDPs, e.g., in occasion O(t) and O(t-n). Then, the DTW (e.g., of PDPs at occasion O(t) and O(t-n)) can be compared to a given threshold.

[0193] In block 1002, the LMF compares the one or more similarity measures to one or more predefined thresholds to determine whether to compensate (e.g., replace) the one or more missed positioning reference signals by utilizing one or more previous positioning reference signals from one or more previous sets of frequency hops. The decision can depend on one or more conditions.

[0194] For example, the one or more conditions can require that the CFP difference for a given PRS interval between time occasions O(t) and O(t-n) is lower than or equal to a predefined threshold CFP th :

[0195] |CFP(bin_id_n, O(t-n) - CFP(bin_id_n, O(t)) | < CFP th

[0196] Alternatively or additionally, the one or more conditions can require that the RSRP difference for a given PRS interval between time occasions O(t) and O(t-n) is lower than or equal to a predefined threshold RSRP th :

[0197] |RSRP(bin_id_n, O(t-n) - RSRP(bin_id_n, O(t)) | < RSRP th

[0198] Alternatively or additionally, the one or more conditions can require that the coherence time between the one or more received positioning reference signals in occasion O(t) and the one or more corresponding positioning reference signals received in occasion O(t-n) is greater than or equal to the duration in which the one or more received positioning reference signals in occasion O(t) and the one or more corresponding positioning reference signals in occasion O(t-n) are measured:

[0199] |CT(bin_id_n, O(t-n) - O(t)) | > O(t) - O(t-n)

[0200] Alternatively or additionally, the one or more conditions can require that the dynamic time warp index between the one or more received positioning reference signals in occasion O(t) and the one or more corresponding positioning reference signals from one or more previous sets of frequency hops from occasion O(t-n) is higher than or equal to a predefined threshold DTWth :

[0201] DTW(bin_id_n, O(t-n) - O(t) > DTW th

[0202] The CFP, RSRP, CT, and / or DTW can be compared for each received PRS interval ID or for an average value over all PRS interval IDs of a given frequency hopping set.

[0203] For example, at least one of the above conditions can need to be satisfied in order to replace one or more missed PRS intervals. As another example, most of the above conditions can need to be satisfied in order to replace one or more missed PRS intervals. As another example, all of the above conditions can need to be satisfied in order to replace one or more missed PRS intervals.

[0204] In block 1003, if one or more conditions are satisfied (block 1002: YES), the LMF determines to replace one or more missed PRS intervals with one or more previous PRS intervals. The one or more missed PRS intervals can be replaced at the UE (as explained above with reference to Figure 7 ) or at the LMF (as explained above with reference to Figure 9 ).

[0205] Alternatively, in block 1004, if one or more conditions are not satisfied (block 1002: NO), the LMF determines that one or more missed PRS intervals do not need to be replaced with one or more previous PRS intervals. In this case, the LMF can prepare or configure at least one RAN node and the UE for retransmission of the one or more missed PRS intervals, as explained above with reference to Figure 8 .

[0206] Figure 11 FIG. 10 illustrates a flowchart of an example embodiment of a method according to what is performed by the apparatus 1400, such as a location server, or the location management function 112 of the core network 110, or any other location management entity.

[0207] Referring to Figure 11 , in block 1101, the apparatus 1400 (or the LMF 112) receives, from a user equipment 100, information indicating at least one or more channel properties of one or more received positioning reference signals 632, 633, 634 of a frequency hopping set 630, and one or more identifiers of one or more missed positioning reference signals of the frequency hopping set 630. The user equipment 100 can be a reduced capability (RedCap) device or any other type of UE.

[0208] Herein, the expression “one or more received positioning reference signals” means that one or more positioning reference signals (PRS intervals) were received by the user equipment 100. The one or more received positioning reference signals can also be referred to as one or more non-missed positioning reference signals (or non-missed PRS intervals). Herein, a positioning reference signal can refer to a downlink positioning reference signal or a sidelink positioning reference signal.

[0209] One or more missed positioning reference signals (PRS intervals) refer to positioning reference signals (PRS intervals) that were transmitted by one or more network nodes 104 but failed to be received or detected by the user equipment 100.

[0210] In block 1102, the apparatus 1400 (or the LMF 112) compensates for the one or more missed positioning reference signals of the set of frequency hops 630 based at least in part on the information.

[0211] The one or more channel characteristics can comprise at least one of: a channel impulse response, a channel flatness probability, a reference signal received power, a reference signal received quality, or a power delay profile.

[0212] The information received from the user equipment 100 can comprise one or more channel characteristics determined by the user equipment 100.

[0213] Alternatively, the information received from the user equipment 100 can comprise compressed raw channel estimates of the one or more received positioning reference signals 632, 633, 634. In this case, the apparatus 1400 (or the LMF 112) can obtain decompressed raw channel estimates of the one or more received positioning reference signals 632, 633, 634 by decompressing the compressed raw channel estimates; and determine the one or more channel characteristics based on the decompressed raw channel estimates.

[0214] The one or more missed positioning reference signals can be compensated for by utilizing one or more previous positioning reference signals 611, 625 from one or more previous sets of frequency hops 610, 620 based at least on the one or more channel characteristics of the one or more received positioning reference signals 632, 633, 634, and one or more corresponding channel characteristics of one or more corresponding positioning reference signals 612, 613, 614, 622, 623, 624 received (by the user equipment 100) in one or more previous sets of frequency hops 610, 620.

[0215] The apparatus 1400 (or LMF 112) can determine a similarity measure (e.g., a difference or a coherence time or a dynamic time warp index) between one or more channel characteristics of the one or more received positioning reference signals 632, 633, 634 and one or more corresponding channel characteristics of one or more corresponding positioning reference signals 612, 613, 614, 622, 623, 624 received in one or more previous frequency hop sets 610, 620; compare the similarity measure to one or more predefined thresholds; and determine whether the one or more missed positioning reference signals are to be compensated for by utilizing one or more previous positioning reference signals 611, 625 from the one or more previous frequency hop sets 610, 620 based at least on the comparison (e.g., as described above with reference to FIG. 6). Figure 10 The apparatus 1400 (or LMF 112) can determine a similarity measure (e.g., a difference or a coherence time or a dynamic time warp index) between one or more channel characteristics of the one or more received positioning reference signals 632, 633, 634 and one or more corresponding channel characteristics of one or more corresponding positioning reference signals 612, 613, 614, 622, 623, 624 received in one or more previous frequency hop sets 610, 620; compare the similarity measure to one or more predefined thresholds; and determine whether the one or more missed positioning reference signals are to be compensated for by utilizing one or more previous positioning reference signals 611, 625 from the one or more previous frequency hop sets 610, 620 based at least on the comparison (e.g., as described above with reference to FIG. 6).

[0216] For example, the apparatus 1400 (or LMF 112) can determine a difference between one or more channel characteristics (e.g., CIR, CFP, RSRP, RSRQ, and / or PDP) of the one or more received positioning reference signals 632, 633, 634 and one or more corresponding channel characteristics of one or more corresponding positioning reference signals 612, 613, 614, 622, 623, 624 from the one or more previous frequency hop sets 610, 620; and compare the difference to one or more predefined thresholds, where the one or more missed positioning reference signals can be compensated for by utilizing the one or more previous positioning reference signals 611, 625 based at least on the difference being below or equal to the one or more predefined thresholds.

[0217] As another example, the apparatus 1400 (or LMF 112) can determine a coherence time between the one or more received positioning reference signals 632, 633, 634 and one or more corresponding positioning reference signals 612, 613, 614, 622, 623, 624 from the one or more previous frequency hop sets 610, 620; and compare the coherence time to a duration in which the one or more received positioning reference signals 632, 633, 634 and the one or more corresponding positioning reference signals 612, 613, 614, 622, 623, 624 from the one or more previous frequency hop sets 610, 620 are measured, where the one or more missed positioning reference signals can be compensated for by utilizing the one or more previous positioning reference signals 611, 625 based at least on the coherence time being above or equal to the duration.

[0218] As another example, the apparatus 1400 (or LMF 112) can determine a dynamic time warp index between the one or more received positioning reference signals 632, 633, 634 and the one or more corresponding positioning reference signals 612, 613, 614, 622, 623, 624 from the one or more previous frequency hop sets 610, 620; and compare the dynamic time warp index to a predefined threshold, wherein the one or more missed positioning reference signals are compensated for by utilizing the one or more previous positioning reference signals 611, 625 based at least on the dynamic time warp index being higher than or equal to the predefined threshold.

[0219] The apparatus 1400 (or LMF 112) can estimate a position of the user equipment 100 based on timing measurements (e.g., time of arrival estimates) associated with the one or more received positioning reference signals 632, 633, 634 and the one or more previous positioning reference signals 611, 625 from the one or more previous frequency hop sets 610, 620.

[0220] The apparatus 1400 (or LMF 112) can transmit an indication to the user equipment 100 that indicates replacing the one or more missed positioning reference signals with the one or more previous positioning reference signals 611, 625 from the one or more previous frequency hop sets 610, 620; and receive, from the user equipment 100 based on transmitting the indication, timing measurements associated with the one or more received positioning reference signals 632, 633, 634 and the one or more previous positioning reference signals 611, 625.

[0221] Alternatively, the apparatus 1400 (or LMF 112) can receive, from the user equipment 100, compressed raw channel estimates of the one or more previous positioning reference signals 611, 625 from the one or more previous frequency hop sets 610, 620; obtain decompressed raw channel estimates of the one or more previous positioning reference signals 611, 625 by decompressing the compressed raw channel estimates of the one or more previous positioning reference signals 611, 625; replace the one or more missed positioning reference signals with the one or more previous positioning reference signals 611, 625 by using the decompressed raw channel estimates of the one or more previous positioning reference signals 611, 625; and determine timing measurements associated with the one or more received positioning reference signals 632, 633, 634 and the one or more previous positioning reference signals 611, 625 based on the replacing.

[0222] Alternatively, the one or more missed positioning reference signals can be compensated for by sending an indication to the user equipment 100 that one or more missed positioning reference signals are prepared for retransmission; and receiving, from the user equipment, timing measurements associated with the one or more received positioning reference signals 632, 633, 634 and the retransmission of the one or more missed positioning reference signals based on sending the indication.

[0223] Figure 12 A flowchart illustrating an example embodiment of a method according to the apparatus 1300 is shown. The apparatus 1300 can be, or can include, or can be included in, a user equipment (UE) 100, 102, for example. The user equipment can be a RedCap device or any other type of UE.

[0224] Reference Figure 12 In block 1201, the apparatus 1300 determines one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set 630.

[0225] The one or more missed positioning reference signals (PRS intervals) refer to positioning reference signals (PRS intervals) that are transmitted by one or more network nodes 104 but failed to be received or detected by the apparatus 1300.

[0226] In block 1202, the apparatus 1300 sends, to a location management entity (e.g., LMF 112 or another location server), information that indicates at least: one or more channel properties of the one or more received positioning reference signals 632, 633, 634 of the frequency-hopping set 630, and the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set 630.

[0227] The one or more received positioning reference signals 632, 633, 634 can also be referred to as one or more non-missed positioning reference signals (or non-missed PRS intervals). Herein, a positioning reference signal can refer to a downlink positioning reference signal or a sidelink positioning reference signal.

[0228] The apparatus 1300 can determine the one or more channel properties of the one or more received positioning reference signals 632, 633, 634 of the frequency-hopping set 630 based on original channel estimates of the one or more received positioning reference signals 632, 633, 634. In this case, the information sent to the location management entity can include the one or more channel properties determined by the apparatus 1300 (e.g., UE 100).

[0229] Alternatively, the apparatus 1300 can obtain compressed raw channel estimates for the one or more received positioning reference signals 632, 633, 634 by compressing one or more raw channel estimates for the one or more received positioning reference signals 632, 633, 634. In this case, the information transmitted to the location management entity can include the compressed raw channel estimates, the compressed raw channel estimates being indicative of the one or more channel properties for the one or more received positioning reference signals 632, 633, 634.

[0230] The apparatus 1300 can transmit, to the location management entity, information associated with the one or more positioning reference signals 611, 612, 613, 614, 622, 623, 624, 625 from the one or more previous frequency hopping sets 610, 620, the information being indicative of at least one or more channel properties for the one or more positioning reference signals 611, 612, 613, 614, 622, 623, 624, 625 from the one or more previous frequency hopping sets 610, 620.

[0231] The apparatus 1300 can receive, from the location management entity, an indication indicating to replace the one or more missed positioning reference signals with one or more previous positioning reference signals 611, 625 from the one or more previous frequency hopping sets 610, 620; based on the indication, replace the one or more missed positioning reference signals with the one or more previous positioning reference signals 611, 625 by using raw channel estimates for the one or more previous positioning reference signals 611, 625; determine, based on the replacement, timing measurements associated with the one or more received positioning reference signals 632, 633, 634 and the one or more previous positioning reference signals 611, 625; and transmit, to the location management entity, the timing measurements associated with the one or more received positioning reference signals 632, 633, 634 and the one or more previous positioning reference signals 611, 625.

[0232] Alternatively, the apparatus 1300 can receive, from the location management entity, an indication indicating to prepare for retransmission of the one or more missed positioning reference signals; based on the indication, receive the retransmission of the one or more missed positioning reference signals (e.g., from at least one network node 104, such as a gNB); determine timing measurements associated with the one or more received positioning reference signals 632, 633, 634 and the retransmission of the one or more missed positioning reference signals; and transmit, to the location management entity, the timing measurements associated with the one or more received positioning reference signals 632, 633, 634 and the retransmission of the one or more missed positioning reference signals.

[0233] The above by means of Figure 7- Figure 12The described blocks, related functions, and information exchanges (messages) are not necessarily performed in the order given and some of them can be performed at the same time or in a different order. Other functions can also be performed between them or within them, and other information can be exchanged, and / or other rules can be applied. Some of the blocks or parts of blocks or one or more pieces of information can also be omitted or replaced by corresponding blocks or parts of blocks or one or more pieces of information.

[0234] As used herein, “at least one of ” and “one or more of ” and similar phrases, in which a list of two or more elements is preceded by “at least one of” or “one or more of”, refers to at least any one element, or to at least any two or more elements, or to at least all elements.

[0235] Figure 13 An example of an apparatus 1300 is illustrated that includes means for performing one or more of the above-described example embodiments. For example, the apparatus 1300 can be an apparatus such as a user equipment (UE) 100, 102, or can be an apparatus that includes a user equipment 100, 102, or can be an apparatus that is included in a user equipment 100, 102. The user equipment can be a reduced capability (RedCap) device or any other type of UE. The user equipment can also be referred to as a wireless communication device, a subscriber unit, a mobile station, a remote terminal, an access terminal, a user terminal, a terminal device, or a user equipment.

[0236] The apparatus 1300 can include circuitry or a chipset adapted to implement one or more of the above-described example embodiments. For example, the apparatus 1300 can include at least one processor 1310. The at least one processor 1310 interprets and executes instructions (e.g., computer program instructions) and processes data. The at least one processor 1310 can include one or more programmable processors. The at least one processor 1310 can include programmable hardware with embedded firmware, and alternatively or additionally, can include one or more application-specific integrated circuits (ASICs).

[0237] The at least one processor 1310 is coupled to the at least one memory 1320. The at least one processor is configured to write data to and read data from the at least one memory 1320. The at least one memory 1320 can include one or more memory units. The memory units can be volatile or non-volatile. It should be noted that there can be one or more non-volatile memory units and one or more volatile memory units, or, alternatively, there can be one or more non-volatile memory units, or, alternatively, there can be one or more volatile memory units. The volatile memory can be, for example, a random access memory (RAM), a dynamic random access memory (DRAM), or a synchronous dynamic random access memory (SDRAM). The non-volatile memory can be, for example, a read-only memory (ROM), a programmable read-only memory (PROM), an electrically programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, an optical storage, or a magnetic storage. Generally, the memory can be referred to as a non-transitory computer-readable medium. The term “non-transitory” as used herein is a limitation of the medium itself (i.e., tangible, rather than a signal), and not a limitation of data storage durability (e.g., RAM vs. ROM). The at least one memory 1320 stores computer-readable instructions executed by the at least one processor 1310 to perform one or more of the above-described example embodiments. For example, the non-volatile memory stores the computer-readable instructions, and the at least one processor 1310 executes the instructions using the volatile memory for temporarily storing data and / or instructions. The computer-readable instructions can refer to computer program code.

[0238] The computer-readable instructions can have been pre-stored to the at least one memory 1320, or, alternatively or additionally, they can be received by the apparatus via an electromagnetic carrier signal, and / or can be copied from a physical entity such as a computer program product. Execution of the computer-readable instructions by the at least one processor 1310 causes the apparatus 1300 to perform one or more of the above-described example embodiments. That is, the at least one processor storing the instructions and the at least one memory can provide means for providing or causing performance of any of the above-described methods and / or blocks.

[0239] In the context of this document, a “memory” or “one computer-readable medium” or “multiple computer-readable media” can be any one or more non-transitory media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer. The term “non-transitory” used herein is a limitation of the medium itself (i.e., tangible, rather than a signal) and not a limitation of data storage durability (e.g., RAM vs. ROM).

[0240] The apparatus 1300 can also include or be connected to an input unit 1330. The input unit 1330 can include one or more interfaces for receiving input. The one or more interfaces can include, for example, one or more temperature, motion, and / or orientation sensors, one or more cameras, one or more microphones, one or more buttons, and / or one or more touch detection units. In addition, the input unit 1330 can include an interface to which an external device can connect.

[0241] The apparatus 1300 can also include an output unit 1340. The output unit can include or be connected to one or more displays capable of rendering visual content, such as light emitting diode (LED) displays, liquid crystal displays (LCD), and / or liquid crystal on silicon (LCoS) displays. The output unit 1340 can also include one or more audio outputs. The one or more audio outputs can be, for example, speakers.

[0242] The apparatus 1300 also includes a connection unit 1350. The connection unit 1350 enables wireless connectivity to one or more external devices. The connection unit 1350 includes at least one transmitter and at least one receiver, which can be integrated to the apparatus 1300 or to which the apparatus 1300 can connect. The at least one transmitter includes at least one transmission antenna, and the at least one receiver includes at least one reception antenna. The connection unit 1350 can include an integrated circuit or a set of integrated circuits that provide the apparatus 1300 with wireless communication capabilities. Alternatively, the wireless connectivity can be an application-specific integrated circuit (ASIC) that is hardwired. The connection unit 1350 can also provide means for performing at least some of the blocks or functions of one or more of the example embodiments described above. The connection unit 1350 can include one or more components controlled by a corresponding control unit, such as power amplifiers, digital front-ends (DFEs), analog-to-digital converters (ADCs), digital-to-analog converters (DACs), frequency converters, (de)modulators, and / or encoder / decoder circuitry.

[0243] It should be noted that the apparatus 1300 can also include various components not shown in FIG. 13A. These various components can be hardware components and / or software components. Figure 13

[0244] Figure 14 FIG. 14 illustrates an example of an apparatus 1400 including means for performing one or more of the example embodiments described above. For example, the means can be a location management function (LMF) 112 of the core network 110, or the means can be a network function virtualization infrastructure.

[0245] ​For example, the apparatus 1400 can comprise circuitry or a chipset adapted to implement one or more of the above-described example embodiments. The apparatus 1400 can be an electronic device or a computing system comprising one or more electronic circuits. The apparatus 1400 can comprise a control circuitry 1410, such as at least one processor, and at least one memory 1420 storing instructions 1422 that, when executed by the at least one processor, cause the apparatus 1400 to perform one or more of the above-described example embodiments. For example, such instructions 1422 can comprise computer program code (software). The at least one processor and the at least one memory storing instructions can provide means for providing or causing execution of any of the above-described methods and / or blocks.

[0246] The processor is coupled to the memory 1420. The processor is configured to read data from and write data to the memory 1420. The memory 1420 can comprise one or more memory units. The memory units can be volatile or non-volatile. It should be noted that there can be one or more non-volatile memory units and one or more volatile memory units, or, alternatively, there can be one or more non-volatile memory units, or, alternatively, there can be one or more volatile memory units. The volatile memory can be, for example, a random access memory (RAM), a dynamic random access memory (DRAM), or a synchronous dynamic random access memory (SDRAM). The non-volatile memory can be, for example, a read-only memory (ROM), a programmable read-only memory (PROM), an electrically programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, an optical storage, or a magnetic storage. Generally, the memory can be referred to as a non-transitory computer-readable medium. The term “non-transitory” as used herein is a limitation of the medium itself (i.e., tangible, rather than a signal) and not a limitation of the durability of data storage (e.g., RAM vs. ROM). The memory 1420 stores computer-readable instructions for execution by the processor. For example, the non-volatile memory stores the computer-readable instructions, and the processor uses the volatile memory to temporarily store data and / or instructions for execution of the instructions.

[0247] The computer-readable instructions can have been pre-stored in the memory 1420, or, alternatively or additionally, they can be received by the apparatus via an electromagnetic carrier signal, and / or can be copied from a physical entity, such as a computer program product. Execution of the computer-readable instructions causes the apparatus 1400 to perform one or more of the above-described functions.

[0248] The memory 1420 can be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and / or removable memory.

[0249] The apparatus 1400 can further include or be connected to a communication interface 1430 comprising hardware and / or software for implementing communication connections according to one or more communication protocols. The communication interface 1430 can include at least one transmitter (Tx) and at least one receiver (Rx), which can be integrated to the apparatus 1400 or to which the apparatus 1400 can be connected. The communication interface 1430 can provide means for performing some of the blocks of one or more of the example embodiments described above. The communication interface 1430 can include one or more components controlled by a corresponding control unit, such as: power amplifiers, digital front end (DFE), analog-to-digital converter (ADC), digital-to-analog converter (DAC), frequency converters, modulators (demodulators), and / or encoder / decoder circuitry.

[0250] The communication interface 1430 provides the apparatus with communication capabilities to communicate in a wireless communication network. For example, the communication interface 1430 can provide a radio, cable, or optical interface to the AMF 111 and / or one or more network nodes 104 of a radio access network. Alternatively or additionally, the communication interface 1430 can provide a radio interface to one or more UEs 100, 102.

[0251] It should be noted that the apparatus 1400 can also include various components not shown in FIG. 14 that are also part of the apparatus. These various components can be hardware components and / or software components. Figure 14

[0252] As used in this application, the term “circuitry” can refer to one or more or all of the following:

[0253] a) hardware-only circuitry implementations (such as implementations in only analog and / or digital circuitry) and

[0254] b) combinations of hardware circuits and software, such as (as applicable):

[0255] i) combinations of analog and / or digital hardware circuits with software / firmware and

[0256] ii) any portions of hardware processor(s) with software (including digital signal processors) that work together to cause an apparatus, such as a mobile phone, to perform various functions and

[0257] c) hardware circuit(s) and / or processor(s), such as a microprocessor(s) or a portion of microprocessor(s), that requires software (e.g., firmware) for operation, but need not necessarily have such software

[0258] present to be operational. This software can include, for instance, firmware or

[0259] ​This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation that is at least partially functional and / or an implementation that is at least partially virtualized. For example, if applicable, the term circuitry also covers a baseband integrated circuit or processor for a mobile device that is at least partially implemented in software, an implementation of the processor as at least one software program, as at least one processor, or as at least one digital signal processor (DSP), as at least one application specific integrated circuit (ASIC), or as at least one field programmable gate array (FPGA), or as at least one processing core of a processor or core of an FPGA, or as at least a portion of an application specific integrated circuit (ASIC), or as at least a portion of a field programmable gate array (FPGA). The term circuitry also covers a GPU, a graphics processor unit, or similar.

[0260] The techniques and methods described herein can be implemented by various means. For example, these techniques can be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or combinations thereof. For a hardware implementation, the apparatus (es) of an example embodiment can be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), graphics processing units (GPUs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described herein, a combination thereof, or the like. For firmware or software, the implementation can be carried out through modules of at least one chip set' s) which perform the functions described herein. The software codes can be stored in memory units and executed by processors. The memory unit can be implemented within the processor or external to the processor, in which case it can be communicatively coupled to the processor via various means as is known in the art. Further, the components of the systems described herein can be rearranged and / or complemented by additional components in order to facilitate the achievements of the various aspects, etc., described

[0261] It will be apparent to those skilled in the art that, with the advance of technology, the inventive concept can be implemented in various ways. The embodiments are not limited to the above-described example embodiments, but can vary within the scope of the claims. Therefore, all words and expressions should be interpreted broadly and they are intended to illustrate, not to limit, the embodiments.

Claims

1. An apparatus for communication, comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to: receive, from a user equipment, information that indicates at least: one or more channel properties of one or more received positioning reference signals of a set of frequency hops, and one or more identifiers of one or more missed positioning reference signals of the set of frequency hops; and compensate for the one or more missed positioning reference signals of the set of frequency hops based at least in part on the information. 2.The apparatus of claim 1, wherein the one or more channel properties comprise at least one of: a channel impulse response, a channel flatness probability, a reference signal received power, a reference signal received quality, or a power delay profile. compressed raw channel estimates of the one or more received positioning reference signals; wherein the apparatus is further caused to: obtain decompressed raw channel estimates of the one or more received positioning reference signals by decompressing the compressed raw channel estimates; and determine the one or more channel properties based on the decompressed raw channel estimates. 4.The apparatus of claim 1, wherein the one or more missed positioning reference signals are compensated for by utilizing one or more previous positioning reference signals from one or more previous sets of frequency hops based at least on the one or more channel properties of the one or more received positioning reference signals and one or more corresponding channel properties of one or more corresponding positioning reference signals received in the one or more previous sets of frequency hops. 5.The apparatus of claim 4, further caused to: determine a similarity measure between the one or more channel properties of the one or more received positioning reference signals and the one or more corresponding channel properties of the one or more corresponding positioning reference signals received in the one or more previous sets of frequency hops; compare the similarity measure to one or more predefined thresholds; and determine whether to compensate for the one or more missed positioning reference signals by utilizing the one or more previous positioning reference signals from the one or more previous sets of frequency hops based at least on the comparison.

3. The apparatus of claim 1, wherein the information received from the user equipment comprises: 6.The apparatus of any one of claims 4-5, further caused to: determine a coherence time between the one or more received positioning reference signals and one or more corresponding positioning reference signals from the one or more previous sets of frequency hops; and compare the coherence time to a duration in which the one or more received positioning reference signals and the one or more corresponding positioning reference signals from the one or more previous sets of frequency hops are measured, wherein the one or more missed positioning reference signals are compensated for by utilizing the one or more previous positioning reference signals based at least on the coherence time being higher or equal to the duration. 7.The apparatus of any one of claims 4-5, further caused to: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ determine a dynamic time warp index between the one or more received positioning reference signals and one or more corresponding positioning reference signals from the one or more previous sets of frequency hops; and compare the dynamic time warp index to a predefined threshold, wherein the one or more missed positioning reference signals are compensated for by utilizing the one or more previous positioning reference signals based at least on the dynamic time warp index being higher or equal to the predefined threshold.

8. The apparatus of any one of claims 4-5, further caused to: estimate a position of the user equipment based at least in part on timing measurements associated with the one or more received positioning reference signals and the one or more previous positioning reference signals from the one or more previous sets of frequency hops.

9. The apparatus of claim 8, further caused to: send an indication to the user equipment that the one or more missed positioning reference signals are to be replaced with the one or more previous positioning reference signals from the one or more previous sets of frequency hops; and receive the timing measurements associated with the one or more received positioning reference signals and the one or more previous positioning reference signals from the user equipment based on sending the indication.

10. The apparatus of claim 8, further caused to: receive compressed raw channel estimates of the one or more previous positioning reference signals from the one or more previous sets of frequency hops from the user equipment; obtain decompressed raw channel estimates of the one or more previous positioning reference signals by decompressing the compressed raw channel estimates of the one or more previous positioning reference signals; replace the one or more missed positioning reference signals with the one or more previous positioning reference signals by using the decompressed raw channel estimates of the one or more previous positioning reference signals; and determine the timing measurements associated with the one or more received positioning reference signals and the one or more previous positioning reference signals based on the replacement.

11. The apparatus of any one of claims 1-3, further caused to: send an indication to the user equipment that the one or more missed positioning reference signals are to be prepared for retransmission, wherein the one or more missed positioning reference signals are compensated for by sending the indication; and receive timing measurements associated with the one or more received positioning reference signals and the retransmission of the one or more missed positioning reference signals from the user equipment based on sending the indication.

12. An apparatus for communication, comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to: determine one or more identifiers of one or more missed positioning reference signals of a set of frequency hops; and send information to a location management entity, the information indicating at least: one or more channel characteristics of one or more received positioning reference signals of the set of frequency hops, and one or more previous positioning reference signals from one or more previous sets of frequency hops. the one or more identifiers of the one or more missed positioning reference signals of the frequency-hopping set.

13. The apparatus of claim 12, further caused to: determine the one or more channel characteristics of the one or more received positioning reference signals of the frequency-hopping set based on raw channel estimates of the one or more received positioning reference signals.

14. The apparatus of claim 12, further caused to: obtain compressed raw channel estimates of the one or more received positioning reference signals by compressing raw channel estimates of the one or more received positioning reference signals, wherein the information sent to the location management entity comprises: the compressed raw channel estimates, the compressed raw channel estimates being indicative of the one or more channel characteristics of the one or more received positioning reference signals.

15. The apparatus of claim 12, further caused to: transmit, to the location management entity, information associated with one or more positioning reference signals from one or more previous frequency-hopping sets, the information being indicative of at least one or more channel characteristics of the one or more positioning reference signals from the one or more previous frequency-hopping sets.

16. The apparatus of claim 15, further caused to: receive, from the location management entity, an indication, the indication being indicative of: replacing the one or more missed positioning reference signals with one or more previous positioning reference signals from the one or more previous frequency-hopping sets; based on the indication, replacing the one or more missed positioning reference signals with the one or more previous positioning reference signals by using raw channel estimates of the one or more previous positioning reference signals; based on the replacing, determining timing measurements associated with the one or more received positioning reference signals and the one or more previous positioning reference signals; and transmitting, to the location management entity, the timing measurements associated with the one or more received positioning reference signals and the one or more previous positioning reference signals.

17. The apparatus of any one of claims 12 to 15, further caused to: receive, from the location management entity, an indication indicative of preparing retransmissions of the one or more missed positioning reference signals; based on the indication, receiving the retransmissions of the one or more missed positioning reference signals; determining timing measurements associated with the one or more received positioning reference signals and the retransmissions of the one or more missed positioning reference signals; and transmitting, to the location management entity, the timing measurements associated with the one or more received positioning reference signals and the retransmissions of the one or more missed positioning reference signals.

18. A method for communication, comprising: receiving, from a user equipment, information, the information being indicative of at least: one or more channel characteristics of one or more received positioning reference signals of a frequency-hopping set, and one or more identifiers of one or more missed positioning reference signals of the frequency-hopping set; and compensating, based at least in part on the information, for the one or more missed positioning reference signals of the frequency-hopping set.

19. A method for communication, comprising: determining one or more identifiers of one or more missed positioning reference signals of a frequency hopping set; and sending information to a location management entity, the information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency hopping set.

20. A non-transitory computer-readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving information from a user equipment, the information indicating at least: one or more channel properties of one or more received positioning reference signals of a frequency hopping set, and one or more identifiers of one or more missed positioning reference signals of the frequency hopping set; and compensating for the one or more missed positioning reference signals of the frequency hopping set based at least in part on the information.

21. A non-transitory computer-readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: determining one or more identifiers of one or more missed positioning reference signals of a frequency hopping set; and sending information to a location management entity, the information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency hopping set.

22. A system for communication, comprising at least a user equipment and a location management entity; wherein the user equipment is configured to: determine one or more identifiers of one or more missed positioning reference signals of a frequency hopping set; and send information to the location management entity, the information indicating at least: one or more channel properties of one or more received positioning reference signals of the frequency hopping set, and the one or more identifiers of the one or more missed positioning reference signals of the frequency hopping set; wherein the location management entity is configured to: receive the information from the user equipment; and compensate for the one or more missed positioning reference signals of the frequency hopping set based at least in part on the information.

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