EP4639811A1

EP4639811A1 - Device, method, and system in a wireless communications network

Info

Publication number: EP4639811A1
Application number: EP22836209.1A
Authority: EP
Inventors: Martin HESSLER; Johan KÅREDAL; Niclas Wiberg
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2022-12-19
Filing date: 2022-12-19
Publication date: 2025-10-29
Also published as: WO2024132093A1

Abstract

A method performed by a device for generating a radio channel model a radio channel between one or more receivers and one or more transmitters in a wireless communications network is provided. The device acquires (205) a first channel tap zone selected from one or more channel tap zones. The first channel tap zone is covering an arbitrary time instant. The first channel tap zone comprises one or more channel taps. Each channel tap is related to a channel snapshot out of at least two time-wise consecutive channel snapshots. Each channel tap is related to a channel propagation path between a respective receiver and a respective transmitter. The device generates (206), for the arbitrary time instant, the radio channel model based on the first channel tap zone. The radio channel model is generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.

Description

DEVICE, METHOD, AND SYSTEM IN A WIRELESS COMMUNICATIONS NETWORK

TECHNICAL FIELD

Embodiments herein relate to a device, a system, and a method therein. In some aspects, they relate to generating a radio channel model of a radio channel between one or more receivers and one or more transmitters in a wireless communications network.

BACKGROUND

In a typical wireless communication network, wireless devices, also known as wireless communication devices, mobile stations, stations (ST A) and/or User Equipments (UE), communicate via a Wide Area Network or a Local Area Network such as a Wi-Fi network or a cellular network comprising a Radio Access Network (RAN) part and a Core Network (CN) part. The RAN covers a geographical area which is divided into service areas or cell areas, which may also be referred to as a beam or a beam group, with each service area or cell area being served by a radio network node such as a radio access node e.g., a Wi-Fi access point or a radio base station (RBS), which in some networks may also be denoted, for example, a NodeB, eNodeB (eNB), or gNB as denoted in Fifth Generation (5G) telecommunications. A service area or cell area is a geographical area where radio coverage is provided by the radio network node. The radio network node communicates over an air interface operating on radio frequencies with the wireless device within range of the radio network node.

3GPP is the standardization body for specifying the standards for a cellular system evolution, e.g., including 3G, 4G, 5G and future evolutions. Specifications for the Evolved Packet System (EPS), also called a Fourth Generation (4G) network, have been completed within the 3rd Generation Partnership Project (3GPP). As a continued network evolution, new releases of 3GPP specifies a 5G network also referred to as 5G New Radio (NR).

Multi-antenna techniques may significantly increase the data rates and reliability of a wireless communication system. The performance is in particular improved if both the transmitter and the receiver are equipped with multiple antennas, which results in a Multiple-Input Multiple-Output (MIMO) communication channel. Such systems and/or related techniques are commonly referred to as MIMO. In addition to faster peak Internet connection speeds, 5G planning aims at higher capacity than current 4G, allowing higher number of mobile broadband users per area unit, and allowing consumption of higher or unlimited data quantities in gigabyte per month and user. This would make it feasible for a large portion of the population to stream high-definition media many hours per day with their mobile devices, when out of reach of Wi-Fi hotspots. 5G research and development also aims at improved support of machine to machine communication, also known as the Internet of things, aiming at lower cost, lower battery consumption and lower latency than 4G equipment.

In the digital world strong advancement, the capability of hardware has opened new opportunities that would have seemed impossible a few years ago. In multiple industries digital twin technology has open up new possibilities, e.g., for training self-driving cares in Virtual Reality (VR) or testing products in VR and/or Augmented Reality (AR). Within radio technology, a radio network digital twin may be used e.g., to investigate network performance or design and to optimize algorithms.

An essential component of a radio network digital twin is a digital representation of the radio environment where the network will operate, by means of the corresponding radio channel. Representing the radio channel requires models of the antennas used by the network nodes, as well as a model of a Radio Frequency (RF) propagation channel, describing how RF signals propagate between nodes of the network. RF propagation channel modelling through ray-tracing may be performed according to the following: Shooting a bundle of rays from a transmission point in a three-dimensional (3D) geometry. Following those rays as they make their way through said geometry by applying different propagation mechanisms, e.g., reflection, diffraction, transmission through surfaces etc. Deducing which of those rays that will arrive at one or several specified reception point, as well as some characteristics of those rays. The 3D geometry is defined beforehand as a computer model of the physical environment, e.g., a city or an indoor office, for which the propagation channel is wanted. The characteristics of a ray may e.g. comprise which path it undertook, e.g., including the directions at which it left the transmission point and arrived at the reception point, respectively, the propagation delay, e.g., the time it takes for an RF signal to travel along that path, and the level of attenuation an RF signal travelling along the path will be subjected to.

This method allows for a highly accurate representation of the RF propagation channel which makes it well suited in the context of constructing radio network digital twins. And thanks to advancements in computing hardware, the RF propagation channel can be generated in the blink of an eye, even in complex environments.

SUMMARY

As part of developing embodiments herein a problem was identified by the inventor and will first be discussed.

A radio network digital twin puts high requirements on continuity of the radio channel, such that the conditions for the network nodes, and hence the performance of the network as a whole, do not change dramatically over time. Continuously modelling a real radio network implies that mobile UEs are allowed to be in motion, i.e., the positions of transmission and/or reception points may change. The same goes for objects distorting the radio signal, i.e., 3D geometry changes. Since this changes the prerequisites of the propagation channel, it has to be repeatedly regenerated, meaning the ray-tracing has to be done anew. How often the propagation channel has to be regenerated depends on the specifics of the set-up, such as the complexity of the 3D environment, the number of network nodes and the speeds at which mobile users and scattering objects move, but despite current state-of-the-art computing hardware being extremely capable, supply will not meet demand for most set-ups of interest: The continuity between the generated propagation channel snapshots would be too low to be used in a radio network digital twin.

An object of embodiments herein is to improve the accuracy of radio channel modelling of a wireless communications network.

According to an aspect of embodiments herein, the object is achieved by a method performed by a device for generating a radio channel model of a radio channel between one or more receivers and one or more transmitters in a wireless communications network.

The device acquires a first channel tap zone selected from one or more channel tap zones. The first channel tap zone is covering an arbitrary time instant. The first channel tap zone comprises one or more channel taps. Each channel tap being related to a channel snapshot out of at least two time-wise consecutive channel snapshots. Each channel tap is related to a channel propagation path between a respective receiver and a respective transmitter.

The device generates for the arbitrary time instant, the radio channel model based on the first channel tap zone. The radio channel model is generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.

According to another aspect of embodiments herein, the object is achieved by a device configured to generate a radio channel model of a radio channel between one or more receivers and one or more transmitters in a wireless communications network. The device is further configured to:

- Acquire a first channel tap zone selected from one or more channel tap zones, which first channel tap zone is adapted to cover an arbitrary time instant, wherein the first channel tap zone is adapted to comprise one or more channel taps, each channel tap adapted to be to related to a channel snapshot out of at least two time-wise consecutive channel snapshots, and each channel tap is adapted to be related to a channel propagation path between a respective receiver and a respective transmitter, and

- generate, for the arbitrary time instant, the radio channel model based on the first channel tap zone, wherein the radio channel model is adapted to be generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.

According to another aspect of embodiments herein, the object is achieved by a system comprising one or more devices configured to generate a radio channel model of a radio channel between one or more receivers and one or more transmitters in a wireless communications network. The system is further configured to:

In this way, an improved radio channel modelling is achieved. This is since when acquiring the first channel tap zone covering the arbitrary time instant, the radio channel model is generated by interpolating between corresponding channel taps of at least two time-wise consecutive channel snapshots.

Embodiments herein may e.g., bring the advantages of achieving an accurate radio channel model, by interpolating between corresponding channel taps of the at least two channel snapshots, and thus achieving a continuous radio channel. This results in a more accurate radio channel model.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of embodiments herein are described in more detail with reference to attached drawings in which:

Figure 1 is a schematic block diagram illustrating embodiments of a wireless communications network.

Figure 2 is a flowchart depicting embodiments of a method in a device.

Figure 3 is a schematic block diagram illustrating examples of embodiments herein.

Figure 4 is a schematic block diagram illustrating examples of embodiments herein.

Figure 5 is a schematic block diagram illustrating embodiments of a device.

Figure 6 schematically illustrates a telecommunication network connected via an intermediate network to a host computer.

Figure 7 is a generalized block diagram of a host computer communicating via a base station with a user equipment over a partially wireless connection.

Figures 8 to 11 are flowcharts illustrating methods implemented in a communication system including a host computer, a base station, and a user equipment.

DETAILED DESCRIPTION Embodiments herein relate to a wireless communications network and the generation of a radio channel model between one or more receivers and one or more transmitters in a wireless communications network.

The propagation channel between a transmission point and a reception point may be described by characteristics of rays that lead from the former to the latter. More specifically, the propagation channel may be described by the propagation paths of those rays, where each propagation path, in turn, may be described by a set of parameters. Combining those parameter sets with models of the antennas used by network nodes at the transmission and reception points, respectively, generates the radio channel.

For a set-up with constantly moving receivers, discontinuities in the resulting radio channel due to insufficiently frequent regeneration of the propagation channel may be avoided by means of interpolation between adjacent channel realizations according to embodiments herein. Interpolation may either be applied directly onto the propagation path parameters, or onto aggregated radio channel weights that are the result of applying antenna models to the propagation path parameters.

In order to apply interpolation, the propagation path generation, such as the raytracing, may e.g., use path identification, giving each propagation path a unique identification (ID) number. When regenerating the radio channel, by means of ray-tracing, after a receiver has moved an increment in space, the ray-tracer output may assign the same ID to a propagation path that has undergone the same propagation mechanisms in the regenerated channel and the previous one, as long as there are only minor changes to the parameters of the propagation path e.g., a small change in its direction of arrival at the reception point.

As mentioned above, the object of embodiments herein is to improve the accuracy of radio channel modelling of a wireless communications network.

Figure 1 is a schematic overview depicting a wireless communications network 100 wherein embodiments herein may be implemented. The wireless communications network 100 comprises one or more RANs and one or more CNs. The wireless communications network 100 may use a number of different technologies, such as Wi-Fi, Long Term Evolution (LTE), LTE-Advanced, 5G, New Radio (NR), 6G, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications/enhanced Data rate for GSM Evolution (GSM/EDGE), or Ultra Mobile Broadband (UMB), just to mention a few possible implementations. Embodiments herein relate to recent technology trends that are of particular interest in a 5G context, however, embodiments are also applicable in further development of the existing wireless communication systems such as e.g. WCDMA and LTE.

A number of RAN nodes operate in the communications network 100 such as e.g. transmitters 101, 102. The transmitters 101 , 102 provides radio coverage in a number of cells which may also be referred to as a beam or a beam group of beams, such as a cell 11 provided by the transmitter 101 , and a cell 12 provided by transmitter 102.

The transmitters 101 , 102 may be any of an NG-RAN node, a transmission and reception point e.g. a base station, a radio access network node such as a Wireless Local Area Network (WLAN) access point or an Access Point Station (AP STA), an access controller, a base station, e.g. a radio base station such as a NodeB, an evolved Node B (eNB, eNode B), a gNB, a base transceiver station, a radio remote unit, an Access Point Base Station, a base station router, a transmission arrangement of a radio base station, a stand-alone access point or any other network unit capable of communicating with a UE, such as e.g., a receiver 121 , 122, within the service area served by the transmitters 101 , 102 depending e.g. on the radio access technology and terminology used. The transmitters 101 , 102 may be referred to as a serving RAN node and communicates with UEs such as the UE 121 , with Downlink (DL) transmissions to the receivers 121 , 122, and in Uplink (UL) transmissions from the receivers 121 , 122.

A number of UEs operate in the communication network 100. The UEs may be receivers or may comprise receivers, such as e.g. the receivers 121, 122. The receivers 121 , 122 may also be referred to as an loT device, a mobile station, a non-access point (non-AP), a STA, and/or a wireless terminal. It should be understood by the skilled in the art that “UE” is a non-limiting term which means any terminal, wireless communication terminal, user equipment, Machine Type Communication (MTC) device, Device to Device (D2D) terminal, a radio device in a vehicle, or node e.g. smart phone, laptop, mobile phone, sensor, relay, mobile tablets or even a small base station communicating within a cell.

One or more devices operates in, or in conjunction with, the wireless communications network 100, such as e.g. the device 110 and the device 111 , e.g. comprised in a system 140. The devices 110, 111 may also be referred to as a cloud nodes 110, 111 , when operating a cloud 150.

Methods herein may be performed by the device 110. As an alternative, a Distributed Node (DN) and functionality, e.g. comprised in the cloud 150 as shown in Figure 1 , may be used for performing or partly performing the methods herein.

According to examples of embodiments herein, e.g., with a number of static transmitters 101 , 102 and a number of moving receivers 121 , 122, a continuous radio channel model may be generated as described below.

Each transmitter 101 , 102 and receiver 121 , 122 may be associated with a unique identity (ID) number. At regular time intervals the propagation paths between the transmitters’ 101 , 102 positions and the current position of each receiver 121 , 122 may be generated through e.g., ray-tracing. The propagation paths generated by one such channel realization may be referred to as a channel snapshot. Each propagation path in the channel snapshot may be assigned an ID number, which may also be referred to as propagation path ID. A propagation path between a certain transmitter 101 , 102 and a certain receiver 121 , 122 that has undergone the same propagation mechanisms as in the previous snapshot will be assigned the same propagation path ID. The snapshot may be fed to an antenna model. This may e.g., mean that an antenna impact is applied to each respective receiver 121 , 122 and transmitter 101 , 102, where each propagation path is converted to a complex-valued channel tap e.g., by combining its path parameters with the antenna impact of the transmitter 101 , 102 and receiver 121 , 122, respectively. The resulting taps, such as channel taps, of consecutive snapshots may be duplicated and stored in a pair-wise fashion. This is performed such that the taps of snapshot k and k+1 are stored together, k+1 and k+2 are stored together, k+2 and k+3 are stored together and so on. Such a pair, containing two sets of taps, those from two consecutive snapshots, is referred to as a zone, such as e.g., a channel tap zone. In some examples, channel taps of more than two channel snapshots are stored together, such that the taps of snapshot k, k+1 and k+2 are stored together, k+1 , k+2 and k+3 are stored together and so on. For sufficiently dense temporal sampling, most paths will be represented in both snapshots of the zone, i.e., a path with a certain propagation path ID will typically have two realizations. Each zone may also comprise time stamps describing when the corresponding snapshots were generated. The zones may be fed to a radio channel generator, or channel emulator. To generate the radio channel model for an arbitrary point in time, the radio channel generator may use a zone, such as a channel tap zone, covering the time in question and calculate for each unique tap within the zone, e.g., as specified by the underlying path’s ID, a complex value corresponding to that time instant by interpolating between the realizations of the tap in the first and second snapshot of the zone. A tap that is not represented in both snapshots of a zone may either be due to the underlying propagation path appearing, e.g., it is represented in the second but not the first snapshot, or disappearing, e.g., it is represented in the first but not the second snapshot, when a receiver moved between the positions corresponding to the two snapshots of the zone. For such taps, interpolation is still done, but they are regarded as having zero strength in the snapshot where they are not represented.

Embodiments herein may e.g., bring the following advantages:

For sufficiently fast channel emulation, i.e., when there is a requirement on how often a new channel realization has to be available, in a use case where the receiver positions are time-varying and not known a priori, providing the necessary means in order to ensure a continuous channel.

In a use case where the receiver positions are known a priori, and/or when there are no time requirements on how often or how fast the channel realizations has to be made available, the provided embodiments may be a means for efficiency. E.g., applying zone interpolation between snapshots generated on a sparser temporal grid will be considerably faster than generating the snapshots themselves densely enough to have a continuous channel.

A channel emulating system that uses zone interpolation between snapshots generated on a sparse temporal grid in order to achieve a denser temporal sampling that may require less memory than a system that directly generates snapshots on the denser temporal sampling grid.

The density of the sampling may thus, according to examples of embodiments herein, be dynamically varied to maintain real-time behavior. Additionally, the sampling may be dynamically varied between users, such as non-stationary receivers, so that denser sampling may be used for a user passing e.g., a corner, and sparser for a user in e.g., an open area without scatterers. A number of embodiments will now be described, some of which may be seen as alternatives, while some may be used in combination.

The embodiments of a method will be generally described in view of the device 110 together with Figure 3. This will be followed by a more detailed description.

A method according to embodiments herein will now be described from the view of the device 110, together with Figure 2. Figure 2 depicts example embodiments of a method performed by the device 110 for generating a radio channel model between one or more receivers 121 , 122 and one or more transmitters 101 , 102 in the wireless communications network 100.

In some embodiments, the device 110 may be referred to as a system comprising one or more devices 110, 110. As will be described more below, the one or more devices 110, 111 may be the device 110 comprising functions such as e.g., a ray-tracer, or equivalently, a propagation path finder, a 3D environment model, a mobility controller, an antenna model, a time unit and a radio channel emulator comprising an interpolator. Alternatively, the one or more devices 110, 111 is a plurality of devices 110, 111 , such as e.g., the ray-tracer, or equivalently, the propagation path finder, the 3D environment model, the mobility controller, the antenna model, the time unit and the radio channel emulator comprising an interpolator, where one or more of these are implemented as standalone devices 110, 111 communicating with each other. Alternatively, at least some of the functions mentioned above may be combined while other are standalone. The method comprises the following actions, which actions may be taken in any suitable order. Actions that are optional are presented in dashed boxes in Figure 2.

Action 201

In some embodiments, prior to generating a respective channel snapshot, the device 110 updates respective positions of the one or more of receivers 121 , 122 in an environment model comprising the one or more receivers 121 , 122 and the one or more transmitters 101 , 102. In other words, the position of each respective receiver 121 , 122 in the environmental model may be checked. If determined that a current position of a respective receiver 121 , 122 is different from a position of that respective receiver 121 , 122 in the environmental model, the position of the respective receiver 121 , 122 in the environmental model is updated to correspond to the current position. Although assumed in embodiments throughout this disclosure that the transmitters 101 , 102 are static, i.e., non-moving, embodiments herein may be extended to comprise non-static transmitters 101 , 102. In such an example, the updating described above is valid also for the transmitters 101 , 102.

Action 202

In some embodiments, the device 110 generates a respective channel snapshot at a number of time instants. The respective channel snapshots comprise one or more propagation paths for each respective receiver 121 , 122. Each propagation path is associated to a respective receiver 121 , 122 and a respective transmitter 101 , 102. Each propagation path is associated with a set of propagation parameters. Thus, generating a respective snapshot may mean that the device 110 generates, calculates or in any other way obtains, the one or more propagation paths for each respective receiver 121 , 122, and collects all propagation paths generated at a certain time instant as a channel snapshot. In other words, a channel snapshot may be said to describe the propagation paths between the respective transmitters 101 , 102 and receivers 121 , 122 at a certain time instant. A channel snapshot may in some examples comprise a time stamp specifying the time the channel snapshot as generated. In some examples, the device 110 generates a respective channel snapshot at a number of time instants and/or at spatial locations.

In some embodiments, generating a respective channel snapshot further comprises assigning a propagation path ID to each propagation path. Propagation paths appearing in time-wise consecutive channel snapshots may be assigned identical propagation path IDs. This may be the case when said propagation paths have undergone the same propagation mechanism in the time-wise consecutive channel snapshots. The same propagation mechanism when used herein may e.g., mean that the propagation path is the same in the sense that any reflection that is part of a propagation path in one channel snapshot also appears in the propagation path of the time-wise consecutive snapshots.

The set of parameters may comprise any one or more out of: A propagation delay, a path attenuation, a polarization scattering matrix, an angle of departure, AoD, an angel of arrival, AoA, and the propagation path ID.

Propagation delay when used herein may e.g., mean the time it takes for a radio wave to travel along the propagation path.

Path attenuation when used herein may e.g., mean the attenuation a radio wave traveling along the propagation path will have suffered when it arrives at the receiver.

Polarization scattering matrix when used herein may e.g., mean how the polarization, the perpendicular components of the electromagnetic field composing a radio wave traveling along the propagation path, has transformed when the wave hits the receiver.

AoD when used herein may e.g., mean the direction, e.g., spatial direction, at which a radio wave travelling along the propagation path leaves the transmitter.

AoA when used herein may e.g., mean the direction, e.g., spatial direction, at which a radio wave travelling along the propagation path arrives at the receiver.

The parameters may e.g., be used by the device 110 when creating channel taps and/or when generating the radio channel model.

Generating snapshots may be performed periodically, e.g., according to a predetermined or configured generating schedule. Alternatively, the device may generate one or more snapshots aperiodically, e.g., upon receiving a request.

Action 203

In some embodiments, the device 110 creates a channel tap for each respective propagation path in the respective channel snapshot. The respective channel taps are created based on the set of parameters associated to the respective propagation path and an antenna impact applied to the respective receiver 121 , 122 and transmitter 101 , 102 associated to the respective propagation path. In other words, the device 110 applies the antenna impact to the respective transmitter 101 , 102 and receiver 121 , 122 and, together with the set of parameters, creates a channel tap for each respective propagation path. The antenna impact may e.g., comprise an antenna orientation of the respective transmitter 101 , 102 and receiver 121 , 122. The antenna orientation may be variable and change over time. Thus, as part of updating the environmental model described above, also the antenna model, comprising the antenna orientation, may be updated to reflect the current antenna orientation of the respective transmitter 101 , 102 and receiver 121 , 122.

Each channel tap may comprise a complex-valued amplitude of the channel tap and a propagation delay of the related propagation path. The complex valued amplitude may e.g., be based on the AoD, AoA, path attenuation, and/or the polarization scattering matrix.

Action 204

In some embodiments, the device 110 stores the one or more channel tap zones. Each channel tap zone comprises a plurality of channel taps from at least two time-wise consecutive channel snapshots. The one or more channel tap zones may e.g., be stored in a memory of the device 110. In some embodiments, storing the one or more channel tap zones comprises any one or more out of storing one or more created channel tap zones and storing one or more channel tap zones obtained from another device. When storing one or more channel tap zone obtained from another device, the storing may further comprise obtaining, such as receiving, e.g., in response to a request or as part of a configured schedule, the one or more channel zones from the other device.

Action 205

The device 110 acquires a first channel tap zone selected from one or more channel tap zones. The first channel tap zone is covering an arbitrary time instant. The first channel tap zone comprises one or more channel taps. Each channel tap is related to a channel snapshot out of at least two time-wise consecutive channel snapshots. Each channel tap is related to a channel propagation path between a respective receiver 121 , 122 and a respective transmitter 101 , 102. The first channel tap zone covering the arbitrary time instant may mean that the arbitrary time instant is a time instant between a first time instant and a second time instant. Here the first time instant is the time for generating the first of the at least two time-wise consecutive snapshots, and the second time instant is the time for generating the last of the at least two time-wise consecutive snapshots. Acquiring the first channel tap zone may, in some embodiments, comprise that the device 110 selects the first channel tap zone from the one or more channel tap zones. The device 110 may then select the first channel tap zone from the one or more channel tap zones such that the first channel tap zones cover the arbitrary time instant.

Acquiring the first channel tap zone may comprise any one out of acquiring a stored channel tap zone generated by the device 110, e.g., as described above, or acquiring a channel tap zone from generated by another device 120.

Action 206

The device 110 generates the radio channel model for the arbitrary time instant. The radio channel model is generated based on the first channel tap zone. The radio channel model is generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone. By interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone, a radio channel model describing a continuous radio channel is achieved.

In some embodiments, a channel tap with a certain propagation path ID in one snapshot of the first channel tap zone does not have a corresponding channel tap, such as not be represented by any channel tap with an identical propagation path ID, in any other channel snapshot in the first channel tap zone. This may be the case when a receiver 121 out the one or more receivers 121 , 122 has changed position between the channel snapshots. This may e.g., be since the propagation path identified with the certain propagation path has disappeared or appeared. When a channel tap does not have a corresponding channel tap, the interpolation is performed between the existing channel tap and one or more synthetic channel taps. A synthetic channel tap may be regarded as a channel tap that has zero strength, i.e., the magnitude of the synthetic channel tap is zero, while the phase remains constant. Further details of the interpolation are explained in below sections of the disclosure.

In some embodiments, interpolating between corresponding channel taps comprises selecting the corresponding channel taps based on the propagation path IDs. This may mean that the device 110 interpolates between channel taps from the at least two time-wise consecutive snapshots of the first channel tap zone that are identified by the same propagation path ID. Thus, the device 110 may select corresponding channel taps that are identified by the same propagation path ID and perform the interpolation between the selected channel taps.

E.g., therefore, corresponding propagation paths in time-wise consecutive channel snapshots may be identified by identical propagation path IDs.

Embodiments mentioned above will now be further described and exemplified. The embodiments below are applicable to and may be combined with any suitable embodiment described above.

According to some examples of embodiments, the device 110 may be represented by a system, such as the system 140 described above. The system may comprise one or more devices 110, 111 , such as e.g., a ray-tracer 301 , or equivalently, a propagation path finder, a 3D environment model 302, a mobility controller 303, an antenna model 304, a time unit 305 and a radio channel emulator 306 comprising an interpolator, e.g., as depicted in Figure 3. The ray-tracer 301 , 3D environmental model 302, mobility controller 303, antenna model 304, time unit 305 and radio channel emulator 306 may be implemented as parts of the device 110, or they may be separately implemented as separate devices 110, 111 to communicate with each other. To put the system 140 into context, one may also add a channel filter that acts as a requester of the radio channel. The channel filter would be connected to some transmit data provider, distort that data by passing it through the filter constituted by the radio channel, and pass the distorted data to some receive data consumer, but since those components are not necessary to describe the method, their description is omitted in the sequel.

The 3D environment model 302 of the physical environment in which the radio channel is to be generated may be available to the ray-tracer 301 as well as the mobility controller 303. It models things such as streets, houses, vegetation, road signs etc. for an outdoor scenario, or walls, floor, ceiling, furniture etc. for an indoor scenario and has a coordinate system in which number of transmitters and receivers, such as e.g., the one or more transmitters 101 , 102 and the one or more receivers 121 , 122, are given coordinates, in the receivers’ case their initial ones. Each transmitter 101 , 102 and receiver 121 , 122 is also assigned an ID number: TX0, TX1 , TX2, ... and RX0, RX1 , RX2, ..., respectively.

Triggered by the time unit 305, the mobility controller 303 may continuously, or periodically, update the receivers’ 121 , 122 positions in the 3D environment model 302. Different principles for updating their positions may be applied. E.g., a receiver 121 may be moving randomly, it may move on a fixed pattern, e.g., between two points in the geometry, or it may move as a result of user input, if the mobility controller 303 has a user interface permitting this. Also triggered by the time unit 305, the mobility controller may request the ray-tracer 301 to generate propagation paths for the entire scenario at the triggered time instant. The ray-tracer 301 thus generates all propagation paths from each transmitter 101 , 102 to the current position of all receivers 121 , 122. The collection of all those propagation paths together with the trigger time is stored as a channel snapshot to be used by the antenna model 304. Each propagation path n is described by the following set of parameters:

• Propagation delay t_n describing the time it takes for a radio wave to travel along the path.

• Path attenuation L_n describing the attenuation a radio wave traveling along the path will have suffered when it arrives at the receiver.

• Polarization scattering matrix describing how the polarization, the perpendicular components of the electromagnetic field composing the radio wave, will have transformed when the wave hits the receiver. • Angle-of-departure describing the (spatial) direction at which the path leaves the transmission point.

• Angle-of-arrival describing the (spatial) direction at which path arrives at the reception point

• Propagation path ID number.

The next time the ray-tracer 301 is triggered by the mobility controller 303, it may perform the same tasks. However, it may keep track of which propagation path ID numbers that have been used and assigns the same ID to any path that has undergone the same propagation mechanisms as at the previous time instant.

Figure 4 shows a simple example scenario with a single transmitter 101 and a receiver 121 moving along some trajectory, where propagation paths have been generated at three different time instants, to, t1 and t2. At the first time instant to, there are two paths leading from transmitter to receiver, these are given propagation path IDs pO and p1. The first path, pO, has undergone a single reflection off the building 401 before arriving at the receiver 121 , whereas the second one, p1 , has undergone two reflections, first off building 402, then off building 403. Note that there is no line-of-sight (LOS) path at this instant, as that path is obstructed by building 402.

At the second time instant t1 , three paths are found by the ray-tracer. The first one is the single-reflected path bouncing off building 401 . Since this path was also found at the previous instant, it is again assigned path ID pO. The second path found is the one double-reflected off the buildings 402, 403, also found at the previous instant and thus assigned path ID p1. The third and last found path is the LOS path, that was not found at the previous instant. It is thus assigned a new propagation path ID p2.

At the third time instant t2, two paths are found. The first is the single reflection off building 401 , the second is the LOS path. Since both were found at the previous instant, path IDs pO and p2, respectively, are reused and assigned to those paths. The doublereflected path is not found at this instant; it is obstructed by building 403.

By applying the antenna impact at transmitter 101 and receiver 121 , respectively, the antenna model 304 uses the propagation path parameters to create, for each propagation path n, a channel tap A_n = {a_n, t_n}, where a_n is the tap’s complex-valued amplitude and t_n its propagation delay. The complex-valued amplitude depends on the direction at which the path departs the transmitter, the direction at which it at the receiver, the propagation loss and the polarization scattering matrix and is given by where ^s the combined gain of the transmit and receive antennas given the polarization scattering induced by the RF propagation, as represented by the polarization scattering matrix V_n. i^s the complex gain vector of the receive antenna and the complex gain vector transmitter of the transmit antenna.

Denoting the collection of channel taps generated from the snapshots collected at time instant t_k as A^k, the antenna model at its output bundles the generated tap collections A^k , A^k+1 , A^k+2 , ... in pairs referred to as channel zones, where each channel zone contains the tap collections from two consecutive snapshots. For instance, the time instants t_k, t_k+1, t_k+2, t_k+3 would result in three channel zones:

The resulting channel zones are provided to the radio channel emulator 306, which uses the zone {A^k, 4^k+1} to generate the radio channel for any time such that t_k < t_t < t_k+1. First the radio channel emulator 306 applies interpolation to each channel tap. If A^k = {a^k, r^k] denotes the channel tap at time t_k and A {a , r ⁺¹ ] denotes the channel tap at time t_k+1, the channel tap at time t_t is given by where

Taps tha t are only represented in one end of the channel zone are treated as follows. For taps that are found only at t_k but not at t_k+1, e.g., due to a propagation path that disappears when the receiver transitions from its position at t_k to its position at t_k+1 the interpolation is done between A* = and a synthetic tap constructed as

Furthermore, the interpolation of the complex tap amplitude a_n ^l is done separately for its magnitude and phase, such that the magnitude fades from |a£| to 0 whereas the phase remains constant.

Similarly, taps that are found only at t_k+1 but not at t_k, e.g., due to a propagation path that appears when the receiver transitions from its position at t_k to its position at t_k+1, the interpolation is done between a synthetic tap constructed as and Again, the interpolation of the complex tap amplitude a_n ^l is done separately for its magnitude and phase, such that the magnitude fades from 0 to |a£⁺¹1 whereas the phase remains constant.

The interpolated path values are then used by the radio channel emulator 306 to construct the radio channel, as represented either in the frequency domain (by its channel transfer function) or the delay/time domain (by its channel impulse response). The channel transfer function between one transmitter and one receiver at carrier frequency f and time t_t is given by if there are N propagation paths between transmitter and receiver. The corresponding channel impulse response is given by Figure 5 shows an example of arrangement in the device 110.

The device 110 may comprise an input and output interface 500 configured to communicate with each other. The input and output interface 500 may comprise a receiver, e.g. wired and/or wireless, (not shown) and a transmitter, e.g. wired and/or wireless, (not shown).

The device 110 is configured to generate a radio channel model of a radio channel between one or more receivers 121 , 122 and one or more transmitters 101 , 102 in the wireless communications network 100.

The device 110 acquires the first channel tap zone selected from one or more channel tap zones. The first channel tap zone is adapted to cover an arbitrary time instant. The first channel tap zone is adapted to comprise one or more channel taps. Each channel tap is adapted to be to be related to a channel snapshot out of at least two time- wise consecutive channel snapshots. Each channel tap is adapted to be related to a channel propagation path between a respective receiver 121 , 122 and a respective transmitter 101 , 102.

The device 110 generates, for the arbitrary time instant, the radio channel model based on the first channel tap zone. The radio channel model is adapted to be generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.

In some embodiment, the device 110 generates, at a number of time instants, a respective channel snapshot adapted to comprise one or more propagation paths for each respective receiver 121 , 122, wherein each propagation path is adapted to be associated to a respective receiver 121 , 122 and a respective transmitter 101 , 102, wherein each propagation path is adapted to be associated with a set of propagation parameters.

The device 110 may create, for each respective propagation path in the respective channel snapshot, a channel tap, based on the set of parameters associated to the respective propagation path and an antenna impact applied to the respective receiver 121 , 122 and transmitter 101 , 102 associated to the respective propagation path, and

The device 110 may store the one or more channel tap zones, wherein each channel tap zone is adapted to comprise a plurality of channel taps from at least two time- wise consecutive channel snapshots. In some embodiments, the device 110, prior to generate a respective channel snapshot, updates, in an environment model adapted to comprise the one or more receivers 121 , 122 and the one or more transmitters 101 , 102, respective positions of the one or more of receivers 121 , 122.

In some embodiments, to generate a respective channel snapshot is further adapted to comprise assign, to each propagation path, a propagation path identity, ID.

In some embodiments, the set of parameters is adapted to comprise any one or more out of:

- A propagation delay,

- a path attenuation,

- a polarization scattering matrix,

- an angle of departure, AoD,

- an angel of arrival, AoA, and

- the propagation path ID.

In some embodiments, propagation paths related to corresponding channel taps in time-wise consecutive channel snapshots are adapted to be identified by identical propagation path IDs, and wherein interpolating between corresponding channel taps is adapted to comprise to select the corresponding channel taps based on the propagation path IDs.

In some embodiments, corresponding channel taps in time-wise consecutive channel snapshots are adapted to be related to corresponding propagation paths.

In some embodiments, to acquire the first channel tap zone is adapted to comprise any one out of:

- Acquire a stored channel tap zone generated by the device 110, or

- acquire a channel tap zone from generated by another device.

In some embodiments, each channel tap is adapted to comprise a complex-valued amplitude of the channel tap and a propagation delay of the related propagation path. The system 140 comprises one or more devices 110, 111 configured to generate the radio channel model of a radio channel between one or more receivers 121 , 122 and one or more transmitters 101 , 102 in the wireless communications network 100.

The system 140 acquires a first channel tap zone selected from one or more channel tap zones. The first channel tap zone is adapted to cover an arbitrary time instant. The first channel tap zone is adapted to comprise one or more channel taps. Each channel tap is adapted to be related to a channel snapshot out of at least two time-wise consecutive channel snapshots. Each channel tap is adapted to be related to a channel propagation path between a respective receiver 121 , 122 and a respective transmitter 101 , 102.

The system 140 generates, for the arbitrary time instant, the radio channel model based on the first channel tap zone. The radio channel model is adapted to be generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.

The embodiments herein may be implemented through a respective processor or one or more processors, such as at least one processor 510 of a processing circuitry in the device 110 depicted in Figure 5, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code for performing the embodiments herein when being loaded into the device 110. One such carrier may be in the form of a CD ROM disc. It is however feasible with other data carriers such as a memory stick. The computer program code may furthermore be provided as pure program code on a server and downloaded to the device 110.

The device 110 may further comprise respective a memory 520 comprising one or more memory units. The memory 520 comprises instructions executable by the processor 510 in the device 110.

The memory 520 is arranged to be used to store instructions, data, configurations, identifiers, indications, notifications, radio channel models, propagation paths, channel taps, channel snapshots, channel tap zones, parameters, environmental models, antenna models and impacts, and applications to perform the methods herein when being executed in the device 110. In some embodiments, a computer program 530 comprises instructions, which when executed by the at least one processor 510, cause the at least one processor 510 of the device 110 to perform the actions above.

In some embodiments, a respective carrier 540 comprises the respective computer program 530, wherein the carrier 540 is one of an electronic signal, an optical signal, an electromagnetic signal, a magnetic signal, an electric signal, a radio signal, a microwave signal, or a computer-readable storage medium.

Those skilled in the art will also appreciate that the functional modules in the device 110, described below may refer to a combination of analog and digital circuits, and/or one or more processors configured with software and/or firmware, e.g. stored in the device 110, that when executed by the respective one or more processors such as the at least one processor 510 described above cause the respective at least one processor 510 to perform actions according to any of the actions above. One or more of these processors, as well as the other digital hardware, may be included in a single Application-Specific Integrated Circuitry (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a system-on-a-chip (SoC).

Further Extensions and Variations

With reference to Figure 6, in accordance with an embodiment, a communication system includes a telecommunication network 3210, such as a 3GPP-type cellular network, which comprises an access network 3211 , such as a radio access network, and a core network 3214. The access network 3211 comprises a plurality of base stations 3212a, 3212b, 3212c, e.g. the transmitters 101 , 102, such as AP STAs NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 3213a, 3213b, 3213c. Each base station 3212a, 3212b, 3212c is connectable to the core network 3214 over a wired or wireless connection 3215. A first user equipment (UE) such as the receivers 121 , 122 and/or a Non-AP STA 3291 located in coverage area 3213c is configured to wirelessly connect to, or be paged by, the corresponding base station 3212c. A second UE 3292 and/or a Non-AP STA in coverage area 3213a is wirelessly connectable to the corresponding base station 3212a. While a plurality of UEs 3291 , 3292 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 3212.

The telecommunication network 3210 is itself connected to a host computer 3230, which may be embodied in the hardware and/or software of a standalone server, a cloud- implemented server, a distributed server or as processing resources in a server farm. The host computer 3230 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 3221 , 3222 between the telecommunication network 3210 and the host computer 3230 may extend directly from the core network 3214 to the host computer 3230 or may go via an optional intermediate network 3220. The intermediate network 3220 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 3220, if any, may be a backbone network or the Internet; in particular, the intermediate network 3220 may comprise two or more sub-networks (not shown).

The communication system of Figure 6 as a whole enables connectivity between one of the connected UEs 3291 , 3292 and the host computer 3230. The connectivity may be described as an over-the-top (OTT) connection 3250. The host computer 3230 and the connected UEs 3291 , 3292 are configured to communicate data and/or signaling via the OTT connection 3250, using the access network 3211 , the core network 3214, any intermediate network 3220 and possible further infrastructure (not shown) as intermediaries. The OTT connection 3250 may be transparent in the sense that the participating communication devices through which the OTT connection 3250 passes are unaware of routing of uplink and downlink communications. For example, a base station 3212 may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 3230 to be forwarded (e.g., handed over) to a connected UE 3291. Similarly, the base station 3212 need not be aware of the future routing of an outgoing uplink communication originating from the UE 3291 towards the host computer 3230.

Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to Figure 7. In a communication system 3300, a host computer 3310 comprises hardware 3315 including a communication interface 3316 configured to setup and maintain a wired or wireless connection with an interface of a different communication device of the communication system 3300. The host computer 3310 further comprises processing circuitry 3318, which may have storage and/or processing capabilities. In particular, the processing circuitry 3318 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer 3310 further comprises software 3311 , which is stored in or accessible by the host computer 3310 and executable by the processing circuitry 3318. The software 3311 includes a host application 3312. The host application 3312 may be operable to provide a service to a remote user, such as a UE 3330 connecting via an OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the remote user, the host application 3312 may provide user data which is transmitted using the OTT connection 3350.

The communication system 3300 further includes a base station 3320 provided in a telecommunication system and comprising hardware 3325 enabling it to communicate with the host computer 3310 and with the UE 3330. The hardware 3325 may include a communication interface 3326 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 3300, as well as a radio interface 3327 for setting up and maintaining at least a wireless connection 3370 with a UE 3330 located in a coverage area (not shown in Figure 7) served by the base station 3320. The communication interface 3326 may be configured to facilitate a connection 3360 to the host computer 3310. The connection 3360 may be direct or it may pass through a core network (not shown in Figure 7) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware 3325 of the base station 3320 further includes processing circuitry 3328, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station 3320 further has software 3321 stored internally or accessible via an external connection.

The communication system 3300 further includes the UE 3330 already referred to. Its hardware 3335 may include a radio interface 3337 configured to setup and maintain a wireless connection 3370 with a base station serving a coverage area in which the UE 3330 is currently located. The hardware 3335 of the UE 3330 further includes processing circuitry 3338, which may comprise one or more programmable processors, applicationspecific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 3330 further comprises software 3331 , which is stored in or accessible by the UE 3330 and executable by the processing circuitry 3338. The software 3331 includes a client application 3332. The client application 3332 may be operable to provide a service to a human or non-human user via the UE 3330, with the support of the host computer 3310. In the host computer 3310, an executing host application 3312 may communicate with the executing client application 3332 via the OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the user, the client application 3332 may receive request data from the host application 3312 and provide user data in response to the request data. The OTT connection 3350 may transfer both the request data and the user data. The client application 3332 may interact with the user to generate the user data that it provides. It is noted that the host computer 3310, base station 3320 and UE 3330 illustrated in Figure 7 may be identical to the host computer 3230, one of the base stations 3212a, 3212b, 3212c and one of the UEs 3291 , 3292 of Figure 6, respectively. This is to say, the inner workings of these entities may be as shown in Figure 7 and independently, the surrounding network topology may be that of Figure 6.

In Figure 7, the OTT connection 3350 has been drawn abstractly to illustrate the communication between the host computer 3310 and the use equipment 3330 via the base station 3320, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the UE 3330 or from the service provider operating the host computer 3310, or both. While the OTT connection 3350 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

The wireless connection 3370 between the UE 3330 and the base station 3320 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 3330 using the OTT connection 3350, in which the wireless connection 3370 forms the last segment. More precisely, the teachings of these embodiments may improve the [select the applicable RAN effect: data rate, latency, power consumption] and thereby provide benefits such as [select the applicable corresponding effect on the OTT service: reduced user waiting time, relaxed restriction on file size, better responsiveness, extended battery lifetime],

A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 3350 between the host computer 3310 and UE 3330, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 3350 may be implemented in the software 3311 of the host computer 3310 or in the software 3331 of the UE 3330, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 3350 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 3311 , 3331 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 3350 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 3320, and it may be unknown or imperceptible to the base station 3320. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer’s 3310 measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 3311 , 3331 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 3350 while it monitors propagation times, errors etc.

Figure 8 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station such as a AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figure 6 and Figure 7. For simplicity of the present disclosure, only drawing references to Figure 8 will be included in this section. In a first step 3410 of the method, the host computer provides user data. In an optional substep 3411 of the first step 3410, the host computer provides the user data by executing a host application. In a second step 3420, the host computer initiates a transmission carrying the user data to the UE. In an optional third step 3430, the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional fourth step 3440, the UE executes a client application associated with the host application executed by the host computer.

Figure 9 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station such as a AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figure 6 and Figure 7. For simplicity of the present disclosure, only drawing references to Figure 9 will be included in this section. In a first step 3510 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In a second step 3520, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step 3530, the UE receives the user data carried in the transmission.

Figure 10 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station such as a AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figure 6 and Figure 7. For simplicity of the present disclosure, only drawing references to Figure 10 will be included in this section. In an optional first step 3610 of the method, the UE receives input data provided by the host computer. Additionally, or alternatively, in an optional second step 3620, the UE provides user data. In an optional substep 3621 of the second step 3620, the UE provides the user data by executing a client application. In a further optional substep 3611 of the first step 3610, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in an optional third substep 3630, transmission of the user data to the host computer. In a fourth step 3640 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure.

Figure 11 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station such as an AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figure 6 and Figure 7. For simplicity of the present disclosure, only drawing references to Figure 11 will be included in this section. In an optional first step 3710 of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In an optional second step 3720, the base station initiates transmission of the received user data to the host computer. In a third step 3730, the host computer receives the user data carried in the transmission initiated by the base station. When using the word "comprise" or “comprising” it shall be interpreted as nonlimiting, i.e. meaning "consist at least of'.

The embodiments herein are not limited to the above described preferred embodiments. Various alternatives, modifications and equivalents may be used.

Claims

1 . A method performed by a device (110) for generating a radio channel model of a radio channel between one or more receivers (121 , 122) and one or more transmitters (101 , 102) in a wireless communications network (100), the method comprising: acquiring (205) a first channel tap zone selected from one or more channel tap zones, which first channel tap zone is covering an arbitrary time instant, wherein the first channel tap zone comprises one or more channel taps, each channel tap being related to a channel snapshot out of at least two time-wise consecutive channel snapshots, and each channel tap is related to a channel propagation path between a respective receiver (121 , 122) and a respective transmitter (101 , 102), and generating (206), for the arbitrary time instant, the radio channel model based on the first channel tap zone, wherein the radio channel model is generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.

2. The method according to claim 1 , the method further comprising: generating (302), at a number of time instants, a respective channel snapshot comprising one or more propagation paths for each respective receiver (121 , 122), wherein each propagation path is associated to a respective receiver (121 , 122) and a respective transmitter (101 , 102), wherein each propagation path is associated with a set of propagation parameters, creating (303), for each respective propagation path in the respective channel snapshot, a channel tap, based on the set of parameters associated to the respective propagation path and an antenna impact applied to the respective receiver (121 , 122) and transmitter (101 , 102) associated to the respective propagation path, and storing (304) the one or more channel tap zones, wherein each channel tap zone comprises a plurality of channel taps from at least two time-wise consecutive channel snapshots.

3. The method according to claim 2, further comprising: prior to generating (302) a respective channel snapshot, updating (301), in an environment model comprising the one or more receivers (121 , 122) and the one or more transmitters (101 , 102), respective positions of the one or more of receivers (121 , 122)

4. The method according to any of claims 2-3, wherein generating (302) a respective channel snapshot further comprises assigning, to each propagation path, a propagation path identity, ID.

5. The method according to any of claims 2-4, wherein the set of parameters comprises any one or more out of:

- a propagation delay,

- a path attenuation,

- a polarization scattering matrix,

- an angle of departure, AoD,

- an angel of arrival, AoA, and

- the propagation path ID.

6. The method according to any of claims 1-5, wherein propagation paths related to corresponding channel taps in time-wise consecutive channel snapshots are identified by identical propagation path IDs, and wherein interpolating between corresponding channel taps comprises selecting the corresponding channel taps based on the propagation path IDs.

7. The method according to any of claims 1-6, wherein corresponding channel taps in time-wise consecutive channel snapshots are related to corresponding propagation paths.

8. The method according to any of claims 1-7, wherein acquiring (305) the first channel tap zone comprises any one out of:

- acquiring a stored channel tap zone generated by the device (110), or

- acquiring a channel tap zone from generated by another device (120).

9. The method according to any of claims 1-8, wherein each channel tap comprises a complex-valued amplitude of the channel tap and a propagation delay of the related propagation path.

10. A computer program (530) comprising instructions, which when executed by a processor (510), causes the processor (510) to perform actions according to any of the claims 1-9.

11. A carrier (540) comprising the computer program (530) of claim 10, wherein the carrier (540) is one of an electronic signal, an optical signal, an electromagnetic signal, a magnetic signal, an electric signal, a radio signal, a microwave signal, or a computer- readable storage medium.

12. A device (110) configured to generate a radio channel model of a radio channel between one or more receivers (121 , 122) and one or more transmitters (101 , 102) in a wireless communications network (100), the device (110) further being configured to: acquire a first channel tap zone selected from one or more channel tap zones, which first channel tap zone is adapted to cover an arbitrary time instant, wherein the first channel tap zone is adapted to comprise one or more channel taps, each channel tap adapted to be related to a channel snapshot out of at least two time-wise consecutive channel snapshots, and each channel tap is adapted to be related to a channel propagation path between a respective receiver (121 , 122) and a respective transmitter (101 , 102), generate, for the arbitrary time instant, the radio channel model based on the first channel tap zone, wherein the radio channel model is adapted to be generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.

13. The device (110) according to claim 12, the method further comprising: generate, at a number of time instants, a respective channel snapshot adapted to comprise one or more propagation paths for each respective receiver (121 , 122), wherein each propagation path is adapted to be associated to a respective receiver (121 , 122) and a respective transmitter (101 , 102), wherein each propagation path is adapted to be associated with a set of propagation parameters, create, for each respective propagation path in the respective channel snapshot, a channel tap, based on the set of parameters associated to the respective propagation path and an antenna impact applied to the respective receiver (121 , 122) and transmitter (101 , 102) associated to the respective propagation path, and store the one or more channel tap zones, wherein each channel tap zone is adapted to comprise a plurality of channel taps from at least two time-wise consecutive channel snapshots.

14. The device (110) according to claim 13, further being configured to: prior to generate a respective channel snapshot, update, in an environment model adapted to comprise the one or more receivers (121 , 122) and the one or more transmitters (101 , 102), respective positions of the one or more of receivers (121 , 122)

15. The device (110) according to any of claims 13-14, wherein to generate a respective channel snapshot is further adapted to comprise assign, to each propagation path, a propagation path identity, ID.

16. The device (110) according to any of claims 13-15, wherein the set of parameters is adapted to comprise any one or more out of:

- a propagation delay,

- a path attenuation,

- a polarization scattering matrix,

- an angle of departure, AoD,

- an angel of arrival, AoA, and

- the propagation path ID.

17. The device (110) according to any of claims 12-16, wherein propagation paths related to corresponding channel taps in time-wise consecutive channel snapshots are adapted to be identified by identical propagation path IDs, and wherein interpolating between corresponding channel taps is adapted to comprise to select the corresponding channel taps based on the propagation path IDs.

18. The device (110) according to any of claims 12-17, wherein corresponding channel taps in time-wise consecutive channel snapshots are adapted to be related to corresponding propagation paths.

19. The device (110) according to any of claims 12-18, wherein to acquire the first channel tap zone is adapted to comprise any one out of:

- acquire a stored channel tap zone generated by the device (110), or

- acquire a channel tap zone from generated by another device.

20. The device (110) according to any of claims 12-19, wherein each channel tap is adapted to comprise a complex-valued amplitude of the channel tap and a propagation delay of the related propagation path.

21. A system (140) comprising one or more devices (110, 111) configured to generate a radio channel model of a radio channel between one or more receivers (121 , 122) and one or more transmitters (101 , 102) in a wireless communications network (100), the system further being configured to: acquire a first channel tap zone selected from one or more channel tap zones, which first channel tap zone is adapted to cover an arbitrary time instant, wherein the first channel tap zone is adapted to comprise one or more channel taps, each channel tap adapted to be related to a channel snapshot out of at least two time-wise consecutive channel snapshots, and each channel tap is adapted to be related to a channel propagation path between a respective receiver (121 , 122) and a respective transmitter (101 , 102), generate, for the arbitrary time instant, the radio channel model based on the first channel tap zone, wherein the radio channel model is adapted to be generated by interpolating between corresponding channel taps of the at least two channel snapshots in the first channel tap zone.