Uplink reference signal resource assignment

Abstract

There is provided a method for assigning an uplink reference signal resource. The method is performed by a first network node of a network. The method comprises assigning (102) a first uplink reference signal resource to a first UE of a first type. A plurality of uplink reference signal resources are separated into a plurality of groups comprising at least a first group and a second group. The first group is reserved for UEs of the first type and the second group is reserved for UEs of a second type. The first uplink reference signal resource is selected from the first group.

Description

[0001] UPLINK REFERENCE SIGNAL RESOURCE ASSIGNMENT

[0002] Technical Field

[0003] The disclosure relates to a method for assigning an uplink reference signal resource, and a network node configured to operate in accordance with that method.

[0004] Background

[0005] In many parts of the world, the currently available frequency bands, at current deployment grids, will be sufficient for the coming 5 to 10 years, assuming that the traffic increase follows current trends and that no disruptive technology that requires substantially higher throughputs arises before that. In 5 to 10 years, network operators will therefore have to densify their networks to meet the growing traffic demands.

[0006] Densifying the networks implies deploying more sites (comprising access points, or the like). However, the more sites that are deployed, the higher the interference levels are expected to be. Already today the operation of some cells is capacity-limited, due to the amount of inter-cell interference occurring during the data peak hours of the day.

[0007] In some examples, the new sites will be provided as small cells, such as picocells or microcells. Although deployment of such small cells in areas with already existing macro cells, sometimes referred to as hetnets, has been studied, actual deployments are rare. One reason for this is that the small cell uptake, i.e. the fraction of user equipments (UEs) served by the small cell compared to the surrounding macro cells is rather low. The low uptake is due to several reasons, where lower transmit power in the small cell and interference from surrounding macro cells are two reasons.

[0008] In further detail, the small cell uptake has traditionally been controlled by, for example, balancing the cell selection offset (CSO) between macro cells and small cells. However, the more the CSO is changed to increase the small cell uptake, the higher the average interference for cell edge UEs become as nothing is done to decrease the transmit power in the macro cells towards the CSO-expanded small cell coverage region.

[0009] Multiple-input, multiple-output (MIMO) is a radio antenna technology that deploys multiple antennas at both the transmitter and receiver to increase the quality, throughput, and capacity of the radio link. In a MIMO system, both downlink (DL) and uplink (UL) transmission may experience inter-layer interference, inter-user interference, and intercell interference (ICI). For DL transmission, beamforming can be applied at network node to generate independent channels for multi-layer or multi-user transmission, which can reduce the complexity in a user equipment (UE) and thus guarantee good performance. The beamforming techniques that have been widely leveraged can be divided into two categories, which are UE feedback-based beamforming and reciprocitybased beamforming.

[0010] For UE feedback-based beamforming, the network node typically uses feedback from the UEs that comprises channel state information (CSI) for downlink beamforming transmission. For example, in the prevalent wireless communication systems (e.g. a fifth generation new radio (5G NR) system), the network node can acquire the CSI feedback from a UE. The CSI feedback can, in general, comprise channel quality information (CQI), a precoding matrix index (PMI) and a rank (Rl) that is calculated by the UE. The network node can use the PMI together with the Rl to form the beamforming for downlink transmission.

[0011] For reciprocity-based beamforming, it is possible to apply the physical channel property of reciprocity and use the UL sounding and channel estimation to obtain the DL channel estimates. The DL channel estimates, consequently, can be used to calculate the precoding weight for the beamforming. The reciprocity-based beamforming solutions can perform much better than UE feedback-based beamforming when the required CSI is available at the network node and the beamforming algorithms are well designed. Especially in a densely deployed cellular system with remarkable ICI, reciprocity-based beamforming can not only create a narrow-concentrated beam of energy towards the direction of a desired UE, but can also intelligently form the beam pattern so that the ICI can be suppressed. In order to achieve these benefits for such a powerful beamforming technique, the key prerequisite is the acquisition of CSI at the network node side, including the intra-cell CSI and channel information related to ICI, so as to improve the signal quality towards desired UEs and suppress interference towards UEs in neighbouring cells.

[0012] One prevalent way to acquire such CSI measurements is to assign UEs with an uplink reference signal. An uplink reference signal (e.g. a sounding reference signal (SRS)) is a reference signal transmitted by a UE in an uplink direction, i.e. from the UE to a network node such as a base station (BS), an gNodeB (gNB), evolved NodeB (eNB), or a NodeB. The uplink reference signal can be used by the network node to estimate an uplink reference signal channel quality over a certain bandwidth.

[0013] There are various existing techniques for assigning uplink reference signal (e.g. SRS) resources in a network, such as for both reciprocity UEs and codebook UEs. The existing techniques, in general, assume that each network node can independently assign the uplink reference signal resources to the UEs served by that network node. When calculating the ICI in order to suppress it, linear averaging of the residual signal over the allocated uplink reference signal resources can be performed. This is the case, for example, with regard to the assignment of an uplink reference signal resource for reciprocity UEs and an uplink reference signal for codebook UEs.

[0014] However, there are various problems with the existing techniques. For example, if a resource assigned for an uplink reference signal is shared by UEs in the same cell according to the existing techniques, there will be higher inter-cell interference on the uplink reference signal. This can lead to large channel estimation errors. Also, with the existing techniques, it not possible for a network node to differentiate the inter-cell interference towards different UEs. Moreover, the existing techniques require a complicated uplink reference signal resource allocation mechanism.

[0015] Summary

[0016] It is an object of the disclosure to obviate or eliminate at least some of the abovedescribed disadvantages associated with existing techniques.

[0017] Therefore, according to an aspect of the disclosure, there is provided a method for assigning an uplink reference signal resource. The method is performed by a first network node of a network. The method comprises assigning a first uplink reference signal resource to a first UE of a first type. A plurality of uplink reference signal resources are separated into a plurality of groups comprising at least a first group and a second group. The first group is reserved for UEs of the first type and the second group is reserved for UEs of a second type. The first uplink reference signal resource is selected from the first group. According to another aspect of the disclosure, there is provided a first network node comprising processing circuitry configured to cause the first network node to assign a first uplink reference signal resource to a first UE of a first type. A plurality of uplink reference signal resources are separated into a plurality of groups comprising at least a first group and a second group. The first group is reserved for UEs of the first type and the second group is reserved for UEs of a second type. The first uplink reference signal resource is selected from the first group.

[0018] According to another aspect of the disclosure, there is provided a computer program comprising instructions which, when executed by processing circuitry, cause the processing circuitry to perform the method described earlier.

[0019] According to another aspect of the disclosure, there is provided a computer program product, embodied on a non-transitory machine-readable medium, comprising instructions which are executable by processing circuitry to cause the processing circuitry to perform the method described earlier.

[0020] Thus, in the manner described above, an improved technique for assigning an uplink reference signal resource is provided. The manner in which an uplink reference signal resource is assigned allows inter-cell interference on a corresponding uplink reference signal to be reduced. This can lead to improvements in channel estimation. It is also possible for the first network node to differentiate the inter-cell interference towards different UEs. Moreover, the manner in which an uplink reference signal resource is assigned is simplified compared to the existing techniques.

[0021] Brief description of the drawings

[0022] For a better understanding of the techniques, and to show how they may be put into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

[0023] Figure 1 is an example communication network;

[0024] Figures 2 and 3 show examples of a resource assignment; Figure 4 shows a method performed by a network node according to an embodiment;

[0025] Figure 5 shows an existing method compared with a method performed by a network node according to an embodiment;

[0026] Figures 6 to 9 show examples of a resource assignment according to some embodiments;

[0027] Figure 10 shows simulation results comparing an existing method with a method performed by a network node according to an embodiment;

[0028] Figure 11 shows a network node in accordance with some embodiments;

[0029] Figure 12 shows a UE in accordance with some embodiments; and

[0030] Figure 13 shows a communication system in accordance with some embodiments.

[0031] Detailed Description

[0032] Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and / or is implied from the context in which it is used. All references to a / an / the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and / or where it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features and advantages of the enclosed embodiments will be apparent from the following description.

[0033] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject-matter disclosed herein, the disclosed subject-matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject-matter to those skilled in the art.

[0034] In some instances, detailed descriptions of well-known methods, nodes, interfaces, circuits, and devices are omitted so as not to obscure the description with unnecessary detail. Those skilled in the art will appreciate that the functions described may be implemented in one or more nodes using hardware circuitry (e.g., analogue and / or discrete logic gates interconnected to perform a specialised function, Application Specific Integrated Circuits (ASICs), Programmable Logic Arrays (PLAs), etc.) and / or using software programs and data in conjunction with one or more digital microprocessors or general purpose computers. Nodes that communicate using an air interface also have suitable radio communications circuitry. Moreover, where appropriate the technology can additionally be considered to be embodied entirely within any form of computer- readable memory, such as solid-state memory, magnetic disk, or optical disk containing an appropriate set of computer instructions that would cause a processor to carry out the techniques described herein.

[0035] As mentioned earlier, there are described herein improved techniques for assigning an uplink reference signal resource. Any of the uplink reference signal resources (e.g. any one or more of the first, second, third, and fourth uplink reference signal resources) referred to herein can be any uplink resource for carrying a reference signal. For example, any of the uplink reference signal resources (e.g. any one or more of the first, second, third, and fourth uplink reference signal resources) referred to herein can be an uplink sounding reference signal (SRS) resource (i.e. an uplink resource for carrying an SRS), an uplink demodulation reference signal (DMRS) resource (i.e. an uplink resource for carrying a DMRS), or any other uplink reference signal resource. Thus, it will be understood that these terms can be used interchangeably herein.

[0036] The techniques described herein can be applied in respect of a variety of types of UE. More specifically, an uplink reference signal resource can be assigned to different types of UE. For example, the techniques can be applied in respect of reciprocity-based beamforming UEs, such as reciprocity UEs, and UE feedback-based beamforming UEs, such as codebook UEs. Herein, reciprocity UEs can be defined as UEs that are served by a network node using a reciprocity-based downlink transmission and codebook UEs can be defined as UEs that are served by a network node using a codebook-based downlink transmission. Alternatively, reciprocity UEs can be defined as UEs that are configured to receive a reciprocity-based downlink transmission and codebook UEs can be defined as UEs that are configured to receive a codebook-based downlink transmission.

[0037] In this disclosure, in order to distinguish an uplink reference signal resource assigned to a codebook UE from an uplink reference signal resource assigned to a reciprocity UE, the uplink reference signal resource assigned to a codebook UE may be referred to as a ‘distress signal’. The distress signal assigned to a codebook UE can be used to indicate that the codebook UE is in distress. The UE may be in distress, for example, when the UE has a poor channel quality (e.g. a channel quality that is less than a threshold channel quality), the UE has poor coverage (e.g. a coverage that is less than a threshold coverage), and / or the UE detects interference (e.g. an interference that is greater than a threshold interference). The distress signal can thus allow action to be taken to minimise or eliminate the distress experienced by the UE, such as by improving the channel quality for the UE, improving the coverage for the UE, and / or reducing or avoiding interference for the UE (e.g. the links of other UEs can be adapted to avoid interfering with the UE that transmits the distress signal). The distress signal assigned to a codebook UE may use the same type of uplink reference signals (e.g. SRS) as those transmitted by other UEs for the purpose of reciprocity-based beamforming.

[0038] Some of the problems with existing techniques will now be described in more detail. Although some of the problems with existing techniques are described with reference to the two types of UE mentioned earlier (namely, reciprocity UEs and codebook UEs), this is merely for illustrative purposes and it will be understood that the problems may equally apply to other types of UE.

[0039] As mentioned earlier, one prevalent way to acquire CSI measurements is to assign UEs with an uplink reference signal (e.g. an SRS).

[0040] Considering the limitation of uplink resources, it is impossible to assign all the UEs in the network with orthogonal uplink reference signals. A good trade-off is to select some UEs in the same cell to be assigned with uplink reference signal resources and the network node can apply reciprocity-based beamforming to serve those selected UEs. The network node can allow UEs in different cells to reuse same time and frequency resources, while with different sequences. In this way, the network node can acquire considerably good channel estimation quality for reciprocity-based beamforming UEs that are associated with the network node and it is also possible to obtain a rough estimate of ICI information by calculating the residual signal after the subtraction of signals transmitted by the UEs in the same cell. With both the desired channel information and ICI information, the network node can apply an existing interferencesuppression precoder for reciprocity-based UEs, such as a minimum mean square error (MMSE) precoder with ICI suppression.

[0041] Typically, for UEs that are not assigned with an uplink reference signal for reciprocitybased beamforming calculation, the network node can serve them by a codebook-based transmission scheme. A codebook-based transmission scheme is based on UE reported CSI. However, those UEs can also face a heavy DL ICI problem, especially in dense deployment scenarios. In order to reduce DL ICI towards codebook UEs, a specific uplink reference signal resource can be assigned to codebook UEs. The network node can measure the ICI experienced by codebook UEs based on those uplink reference signal resources and perform beamforming with ICI suppression to null ICI towards the codebook UEs.

[0042] Figure 1 is an example communication network illustrating such a scheme. UEO is a cell edge user with DL codebook transmission in CellO and UE1 is a cell centre user with DL reciprocity transmission in Celli . According to existing techniques, UEO is assigned with a distress signal so that Celli can measure the ICI from UEO. When Celli transmits DL data to UE1 with a reciprocity based precoder, the transmit beamforming weights can be calculated with the aim of both concentrating signal power toward UE1 and nulling signal power towards UEO. In this way, UEO is protected from DL ICI, and thus throughput gains are brought to UEO.

[0043] As mentioned earlier, a first problem with existing techniques is that, if a resource assigned for an uplink reference signal (e.g. SRS) is shared by UEs in the same cell, there will be higher inter-cell interference on the uplink reference signal and this can lead to large channel estimation errors. With limited orthogonal uplink reference signal resource for a cell, only some UEs can obtain uplink reference signal resources for reciprocity beamforming. Codebook UEs without an uplink reference signal will transmit DL data based on UE reported channel state information (CSI). Existing techniques aim to assign codebook UEs with an uplink reference signal (distress signal) to protect codebook UEs from DL interference caused by neighbouring cells’ DL transmission. However, with limited uplink reference signal resource, it is not feasible to assign dedicated uplink reference signal resources for each UE served by the codebook-based transmission scheme, especially when there are a large number of UEs.

[0044] In order to reduce uplink reference signal cost, another existing technique allows all codebook UEs in a cell to share the same uplink reference signal resource, which can be referred to as a cell-level distress signal. That is, all the codebook UEs in the same cell are allowed to transmit an uplink reference signal on the same resource. Even though the uplink reference signal overhead can be reduced, the power on the uplink reference signal resource assigned for the distress signal will be the accumulation of all codebook UEs and it may be that the uplink reference signal resource for the distress signal in one cell collides with the uplink reference signal resource used for reciprocity beamforming calculation in another cell. This can cause severe inter-cell interference from the cell-level distress signal to the uplink reference signal on the same uplink reference signal resource used in neighbouring cells for reciprocity-based beamforming weight calculation, and a larger channel estimation error for the corresponding uplink reference signal channel.

[0045] Figure 2 is an example of a resource assignment according to existing techniques. Each block in the plot shown in Figure 2 represents one orthogonal full band (e.g. full frequency bandwidth) uplink reference signal resource with a different comb, cyclic shift, or symbol.

[0046] Figure 3 is a more detailed example of a resource assignment according to existing techniques, which involves multiple cells. A specific example will be described with reference to Figure 3 to further illustrate the problems with existing techniques.

[0047] As illustrated in Figure 3, in existing techniques, there is a single pool of uplink reference signal resources. There is no separation of the uplink reference signal resource pool and no coordination among cells on the uplink reference signal resource pool. In other words, all of the cells assign their own uplink reference signal resources independently.

[0048] Thus, in the example illustrated in Figure 3, three cell level distress signals are assigned to codebook UEs in three corresponding cells (as represented by the filled blocks in Figure 3). For each cell level distress signal, there can be a large number of codebook UEs transmitting the same uplink reference signal simultaneously. Moreover, each reciprocity UE is assigned with a different uplink reference signal resource in a corresponding cell (as represented by the unfilled blocks in Figure 3). There will be severe interference on the uplink reference signal of the reciprocity UEs, which is caused by the cell level distress signals in the neighbouring cells.

[0049] As also mentioned earlier, a second problem with existing techniques is that it is not possible for a network node to differentiate the inter-cell interference towards different UEs, e.g. reciprocity UEs and codebook UEs. In existing techniques, a reciprocity used uplink reference signal resource and distress signal share the same uplink reference signal resource pool, which makes it difficult for a cell to distinguish interference measured from neighbouring cells’ reciprocity UEs and neighbouring cells’ codebook UEs. Moreover, it can be important to distinguish between different UEs’ interference for performance optimization. For example, in a large coverage cell scenario, an uplink reference signal (distress signal) from a cells’ codebook UEs can be very weak compared with a neighbouring cells’ reciprocity used uplink reference signal. This will lead to a weak performance for codebook UEs’ interference nulling, since the nulling mechanism concentrates more on strong inter-cell interference. However, if a cell can distinguish the interference between different groups of UEs, specific enhancement can be added to interference measured from neighbouring cells’ codebook UEs. Thus, DL nulling performance can be improved for codebook UEs in neighbouring cells.

[0050] As also mentioned earlier, a third problem with existing techniques is that they require a complicated uplink reference signal resource allocation mechanism. An uplink reference signal (distress signal) resource for codebook UEs can be very different from a reciprocity used SRS resource, since a distress signal is targeted for use by codebook UEs’ inter-cell interference measurement and is not used to measure channel information for DL transmission as a reciprocity used uplink reference signal does. For example, a reciprocity used uplink reference signal is usually measured in full band (e.g. full frequency bandwidth) with all ports of a UE, while a distress signal can be narrowband with fewer ports of the UE. The diversity of uplink reference signal usage brings challenges for existing SRS allocation techniques.

[0051] However, at least some of the above-described problems can be obviated or eliminated by way of the improved techniques for assigning an uplink reference signal resource, which are described herein.

[0052] The techniques described herein involve a first network node of a network. The network referred to herein can be any type of network. For example, the network referred to herein may be a communications or telecommunications network. In some embodiments, the network referred to herein can be a mobile network, such as a fifth generation (5G) mobile network, a sixth generation (6G) mobile network, or any other generation mobile network. In some embodiments, the network referred to herein can be a core network (e.g. a 5G core (5GC) network) or a radio access network (RAN). In some embodiments, the network referred to herein can be a virtual network or an at least partially virtual network. Although some examples have been provided for the type of network referred to herein, it will be understood that the network referred to herein can be any other type of network.

[0053] Figure 4 illustrates a method performed by a first network node of a network in accordance with an embodiment. The method is for assigning an uplink reference signal resource. The network node 500 described later with reference to Figure 11 can be configured to operate in accordance with the method described with reference to Figure 4. For example, the method described with reference to Figure 4 can be performed by or under the control of the processing circuitry 502 of the network node 500 described later with reference to Figure 11 .

[0054] With reference to Figure 4, as illustrated by block 102, a first uplink reference signal resource is assigned to a first UE of a first type. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) assigns the first uplink reference signal resource to the first UE. A plurality of uplink reference signal resources are separated into a plurality of groups comprising at least a first group and a second group. The first group is reserved for UEs of the first type and the second group is reserved for UEs of a second type. The first uplink reference signal resource is selected from the first group.

[0055] Although the method is described with reference to a first and second group, it will be understood that the plurality of groups may comprise more than two groups (e.g. three or even more groups) according to some embodiments. There are separate groups of uplink reference signal resources for different types of UE. For example, there may be a different group of uplink reference signal resources for each type of UE. Also, although the method is described with reference to a first uplink reference signal resource being assigned to a first UE of a first type, it will be understood that the first uplink reference signal resource may be assigned to more than one UE (or even all UEs) of the first type according to some embodiments.

[0056] In some embodiments, at least one other UE of the first type is assigned the same first uplink reference signal resource as the first UE. That is, in some embodiments, the same uplink reference signal resource in the same group can be reused. It can be advantageous for uplink reference signal resources in the same group to be reusable. For example, in some of these embodiments, if a sequence of the uplink reference signal (e.g. SRS) is known, a composite channel of the interference can be estimated, and the strongest channel taps can be selected to null the interference. The composite channel can be a channel that combines the channel of the UEs using the same uplink reference signal on the same resource. An example of the sequence is a predefined bit sequence. There are a number of alternatives and any of these in common with the time or frequency resources can be part of an uplink reference signal resource, which may be assigned to a specific UE or a group of UEs.

[0057] Although not illustrated in Figure 4, in some embodiments, the method may comprise changing the first uplink reference signal resource assigned to the first UE to a second uplink reference signal resource in response to the first UE changing from the first type to the second type. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may change the first uplink reference signal resource in this way. In these embodiments, the second uplink reference signal resource is selected from the second group. Although also not illustrated in Figure 4, in some embodiments, the method may comprise assigning a third uplink reference signal resource to a second UE of the second type. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may assign the third uplink reference signal resource to the second UE. In these embodiments, the third uplink reference signal resource is selected from the second group. In some of these embodiments, the method may comprise changing the third uplink reference signal resource assigned to the second UE to a fourth uplink reference signal resource in response to the second UE changing from the second type of UE to the first type of UE. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may change the third uplink reference signal resource in this way. In these embodiments, the fourth uplink reference signal resource is selected from the first group.

[0058] Although not illustrated in Figure 4, in some embodiments, the method may comprise separating the plurality of uplink reference signal resources into the plurality of groups. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may perform this separating step.

[0059] In some embodiments, the second group may comprise (e.g. significantly) more of the plurality of uplink reference signal resources than the first group. Thus, for example, a major part of the plurality of uplink reference signal resources may be used for UEs of the second type, whereas a minor part of the plurality of uplink reference signal resources may be used for UEs of the first type. In one example, the ratio of the number of uplink reference signal resources used for UEs of the first type (e.g. codebook UEs) to the number of uplink reference signal resources used for UEs of the second type (e.g. reciprocity UEs) may be 1 :15. However, it will be understood that this ratio can depend on a variety of conditions and thus other examples are also possible.

[0060] Although also not illustrated in Figure 4, in some embodiments, the method may comprise changing the plurality of groups in response to a change in a ratio of the UEs of the first type and the UEs of the second type. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may change the plurality of groups. It can be the case that the plurality of groups are changed in the same way among multiple cells, such as the cell served by the first network node and at least one other (e.g. neighbouring) cell. This can ensure that the grouping method among cells is the same.

[0061] Although also not illustrated in Figure 4, in some embodiments, the method may comprise one or both of reserving the first group for UEs of the first type and reserving the second group for UEs of the second type. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may reserve one or both of the first group and second group in this way.

[0062] In some embodiments, the first network node may be configured with information indicative of the plurality of groups. For example, the first network node may be configured with the information when a cell to be served by the first network node is set up in the network.

[0063] Although not illustrated in Figure 4, in some embodiments, the method may comprise informing at least one second network node of the network about the plurality of groups. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may inform at least one second network node of the network about the plurality of groups. For example, informing at least one second network node of the network may comprise informing all other network nodes of the network or informing each network node of the network that is configured to serve a cell neighbouring a cell that the first network node is configured to serve.

[0064] In some embodiments, the first UE may be classified as the first type based on a downlink channel quality that the first UE has.

[0065] Although not illustrated in Figure 4, in some embodiments, the method may comprise one or both of scheduling uplink signalling for the first UE on the first uplink reference signal resource and performing measuring on the first uplink reference signal resource. That is, the first network node (e.g. the network node 500 or, more specifically, the processing circuitry 502 of the network node 500) may perform one or both of these scheduling and measuring steps.

[0066] In some embodiments, the first uplink reference signal resource may have a first frequency bandwidth. In some embodiments involving the third uplink reference signal resource, the third uplink reference signal resource may have the same frequency bandwidth as the first uplink reference signal resource. That is, the third uplink reference signal resource may also have the first frequency bandwidth. In some embodiments, the uplink signalling for the first UE may be scheduled on a first part of the first frequency bandwidth and the measuring may be performed on a second part of the first frequency bandwidth. In other embodiments, the uplink signalling for the first UE may be scheduled on the full first frequency bandwidth.

[0067] In some embodiments, the first UE may be in a first cell served by the first network node. In some of these embodiments, the first uplink reference signal resource may be assigned to at least one other UE of the first type in a second cell served by a second network node of the network. The second cell may neighbour the first cell. Thus, in some embodiments, the plurality of groups can be applied for use by the same type of UE over a plurality of cells.

[0068] In some embodiments, the first uplink reference signal resource assigned to the at least one other UE may have a second frequency bandwidth. In these embodiments, the second frequency bandwidth may be different from the first frequency bandwidth. In some embodiments, uplink signalling for the at least one other UE may be scheduled on a first part of the second frequency bandwidth. The first part of the second frequency bandwidth can be within the second part of the first frequency bandwidth. In other embodiments, uplink signalling for the at least one other UE may be scheduled on the full second frequency bandwidth.

[0069] In some embodiments, UEs of the first type can be UEs that are served using a first downlink transmission mode and UEs of the second type can be UEs that are served using a second downlink transmission mode. In some embodiments, the first downlink transmission mode may use a codebook based downlink transmission and the second downlink transmission mode uses a non-codebook based downlink transmission. In some embodiments, the non-codebook based downlink transmission may be a reciprocity based downlink transmission or a grid of beam (GoB) downlink transmission.

[0070] In other embodiments, UEs of the first type can be UEs that are assigned a first priority and UEs of the second type can be UEs that are assigned a second priority. UEs of the first type can be assigned a first priority according to a target set for those UEs, such as a target throughput for those UEs, a target quality of service (QoS) for those UEs, or any other target for those UEs. Similarly, UEs of the second type can be assigned a second priority according to a target set for those UEs, such as a target throughput for those UEs, a target QoS for those UEs, or any other target for those UEs.

[0071] Therefore, improved techniques for assigning an uplink reference signal resource are provided.

[0072] Advantageously, considering the different purpose of an uplink reference signal resource for different types of UE (e.g. codebook UEs and reciprocity UEs, or any other types of UE), the techniques described herein separate an uplink reference signal pool for the different types of UE. That is, a single uplink reference signal pool (comprising a plurality of uplink reference signal resources) can be separated into a plurality of groups (each comprising at least one of the plurality of uplink reference signal resources). In addition, there can be coordination among cells for the uplink reference signal resource group allocation to ensure that the uplink reference signal resource group allocation among cells is aligned. That is, the cells can align their uplink reference signal resource group allocations with each other.

[0073] With the separated uplink reference signal pool and optionally also the coordination among cells, when UEs of a first type (e.g. codebook UEs) in a cell share the same uplink reference signal resource (cell level distress signal), it will not cause a large uplink reference signal channel estimation error to an uplink reference signal used by UEs of a second type (e.g. reciprocity UEs) in neighbouring cells. An uplink reference signal used by UEs of the first type (e.g. a codebook used uplink reference signal) can be narrowband and Frequency Domain Multiplexed (FDMed) between cells, which will not impact the uplink reference signal (distress signal) in neighbouring cells.

[0074] In order to further leverage the benefit of the above allocation and optional coordination of uplink reference signal resource groups, a scaling of ICI for different types of UE can be implemented, so as to allow the first network node to focus more on the nulling capability to the UEs of the first type (e.g. codebook UEs) that are suffering more ICI.

[0075] The uplink reference signal resource allocation method described herein can optionally be simplified further by using separated uplink reference signal resource groups for different uplink reference signal usage. It will be understood that advantages, such as this and others described herein, may be achieved despite the fact that the number of uplink reference signal resources may be limited. Also, if just one or a few uplink reference signal resources are allocated to the first group of UEs, this first group of UEs may experience reduced ICI.

[0076] According to an embodiment, a proposed method that separates an uplink reference signal resource pool for a first type of UE and a second type of UE can comprise the following steps. In a first step, the first network node may determine a corresponding uplink reference signal resource group for UEs of the first type and UEs of the second type. In a second step, the first network node may configure and / or schedule UEs with an uplink reference signal resource from their corresponding group. In a third step, the first network node may measure uplink inter-cell interference on the uplink reference signal resource. In a fourth step, the first network node may calculate downlink beamforming weights for the UEs based on the inter-cell interference measurement result on the different resource groups, which may involve a scaling of inter-cell interference for the different types of UE.

[0077] Figure 5 illustrates a comparison of an existing method with such a proposed method according to an embodiment. The network node 500 described later with reference to Figure 11 can be configured to operate in accordance with the proposed method illustrated in Figure 5. For example, the proposed method described with reference to Figure 5 can be performed by or under the control of the processing circuitry 502 of the network node 500 described later with reference to Figure 11 .

[0078] As shown in Figure 5, the existing method comprises three steps 202, 204, 206. At step 202 of Figure 5, a network node assigns an uplink reference signal resource to the target UEs. At step 204 of Figure 5, the network node performs scheduling or measuring for a beamforming weight calculation. At step 206 of Figure 5, the network node performs this beamforming weight calculation. In addition to the existing method, the proposed method separates an uplink reference signal resource pool for different types of UE into different groups and processes measurement on the configured uplink reference signal resource for the beamforming weight calculation. In more detail, as also shown in Figure 5, the proposed method comprises four steps 300, 302, 304, 306. At step 300 of Figure 5, a plurality of uplink reference signal resources are separated into a plurality of groups. That is, a plurality of uplink reference signal resource groups are determined. Thus, the previously mentioned single uplink reference signal resource pool is separated into a plurality of groups (or pools). The plurality of groups comprise at least a first group and a second group. The first group is reserved for UEs of a first type (e.g. codebook UEs) and the second group is reserved for UEs of a second type (e.g. reciprocity UEs). In this way, there are separate uplink reference signal resource groups for UEs of the first type and UEs of the second type. In some embodiments, the allocation of the uplink reference signal resource groups may be aligned across all cells in the target deployment. That is, the cells can align their uplink reference signal resource group allocations with each other.

[0079] At step 302 of Figure 5, a first uplink reference signal resource is assigned to a first UE of the first type. The first uplink reference signal resource is selected from the first group. That is, step 302 of Figure 5 involves assigning an uplink reference signal resource from a corresponding uplink reference signal resource group.

[0080] In more detail, based on the determined groups in step 300 of Figure 5, the first network node may assign an uplink reference signal resource from a corresponding group to connected UEs, such as by radio resource control (RRC). In an example, a UE has good downlink channel quality (e.g. according to a UE CSI report) and the first network node decides to transmit downlink data to the UE with reciprocity beamforming. As such, the first network node assigns, to the UE, an uplink reference signal resource selected from a group that is reserved for reciprocity UEs. Alternatively, if the first network node instead decides to transmit downlink data to the UE with codebook-based beamforming, the first network node then assigns, to the UE, an uplink reference signal resource selected from a group that is reserved for codebook UEs. In another example, the first network node may determine the downlink transmission mode dynamically. In this case, the first network node may assign, to the UE, an uplink reference signal resource from both groups. The first network node may then trigger one of these uplink reference signal resources dynamically, such as by downlink control information (DCI).

[0081] In some embodiments, all UEs of the first type (e.g. all codebook UEs) in a cell may be allocated with same first uplink reference signal resource from the first group that is reserved for UEs of the first type. In some embodiments, the first uplink reference signal resource from the first group that is reserved for UEs of the first type may be configured with a different uplink reference signal power target from the third uplink reference signal resource from the second group that is reserved for UEs of the second type. In some embodiments, the first uplink reference signal resource from the first group that is reserved for UEs of the first type may be configured with a different uplink reference signal bandwidth from the third uplink reference signal resource from the second group that is reserved for UEs of the second type.

[0082] At step 304 of Figure 5, uplink signalling (e.g. an uplink SRS) is scheduled for the first UE on the first uplink reference signal resource and / or measuring is performed on the first uplink reference signal resource. In some embodiments, the scheduling and measuring can be on a corresponding uplink reference signal resource. In some embodiments, the scheduling of assigned uplink signalling (e.g. an assigned uplink SRS) for UEs may be triggered periodically, aperiodically, or semi-persistently. The measuring that is performed can comprise measuring inter-cell interference. The first network node can measure the inter-cell interference on the first uplink reference signal resource that is assigned at step 302 of Figure 5.

[0083] In an example, the inter-cell interference from UEs of the first type (e.g. codebook UEs) in neighbouring cells can be measured on a part of the first (e.g. full band or full bandwidth) uplink reference signal resource (e.g. the second part 1010 of the first uplink reference signal resource 1004 of Figure 8, which is described later), by calculating receive signals on a frequency used by the neighbouring cells. In this example, an intercell interference matrix Qdistressfor the UEs of the first type can be calculated as follows:

[0084] Qdistress ~ distress^ distress (1) where Rdistressis areceived signal on the uplink reference signal (distress signal) for UEs of the first type (which is in the form of a matrix) and Rdistressis aconjugate transpose of Rdistress-

[0085] In another example, the inter-cell interference from UEs of the first type (e.g. codebook UEs) in neighbouring cells can be measured on the first (e.g. full band or full bandwidth) uplink reference signal resource (e.g. the first uplink reference signal resource 1104 of Figure 9, which is described later) and the inter-cell interference from UEs of the second type (e.g. reciprocity UEs) in neighbouring cells can be measured on another (e.g. full band or full bandwidth) uplink reference signal resource (e.g. the second uplink reference signal resource 1106 of Figure 9, which is described later) in the following manner. Specifically, in this example, an inter-cell interference matrix Qdistress for the UEs of the first type can be calculated as follows:

[0086] Qdistress ~ ^^^distress^^^ distress (?) where Resdistressis a residual signal for the uplink reference signal (distress signal) for UEs of the first type (which is in the form of a matrix), Resdistressis a conjugate transpose of Resdistress, Rdistressis areceived signal on the uplink reference signal (distress signal) for UEs of the first type, Hdistress kis an estimated channel based on k-th uplink reference signal resource of the uplink reference signal (distress signal) for UEs of the first type, and Sdistress kis a transmitted signal on the k-th uplink reference signal resource of the uplink reference signal (distress signal) for UEs of the first type.

[0087] Also, in this example, an inter-cell interference matrix Qrecifor the UEs of the second type can be calculated as follows:

[0088] Qreci ~ ResreciResreci(4) where Resreciis a residual signal for UEs of the second type (which is in the form of a matrix), Resed is a conjugate transpose of Resreci, Rredis areceived signal on the uplink reference signal resource for UEs of the second type, Hreci kis an estimated channel based on the k-th uplink reference signal resource for UEs of the second type, and Sreci kis a transmitted signal on the k-th uplink reference signal resource for UEs of the second type. In order to leverage the differentiation of different uplink reference signal resource groups, the inter-cell interference matrices for UEs of the first type and UEs of the second type may be added up (or summed). In some embodiments, the inter-cell interference matrices for UEs of the first type and UEs of the second type may be added up with different scaling factors as follows:

[0089] Q ~aoQ distress T ^iQreci (®) where QdiStressisthe inter-cell interference matrix for the UEs of the first type, a0is the scaling factor for the inter-cell interference matrix for the UEs of the first type, Qreciis the inter-cell interference matrix for the UEs of the second type, and aris the scaling factor for the inter-cell interference matrix for the UEs of the second type. Both scaling factors a0and arcan have a value greater than or equal to zero (i.e. a0> 0 and ar> 0) .

[0090] The larger a scaling factor, the more the emphasis on the inter-cell interference measured on the corresponding group in the total inter-cell interference. In this way, it is possible to cancel more inter-cell interference towards the UEs of the first type. For example, where UEs of the first type are codebook UEs, downlink beamforming can cancel more inter-cell interference towards the codebook UEs. As such, a higher throughput can be achieved for the codebook UEs.

[0091] The information on inter-cell interference described herein can be used for a physical data shared channel (PDSCH), a physical downlink control channel (PDCCH) such as to reduce discontinuous transmission (DTX), or any other control channel.

[0092] Returning back to Figure 5, at step 306, a beamforming weight calculation is performed. In an example, with a minimum mean square error (MMSE) weight calculation method for reciprocity-based beamforming, beamforming weights W for a UE can be calculated as follows:

[0093] W = Q- tHQ-1!!11+ / )-1(7) where H is an estimated channel of the UE, HHis a conjugate transpose of H, Q is a measured inter-cell interference matrix (such as any of those calculated according to step 304 of Figure 5 in the manner described above), and I is an identify matrix. The identify matrix I has the same size as the HQ^H" matrix. The identify matrix I is a diagonal matrix that has “ones” on the main diagonal elements and “zeros” on all of the off diagonal elements. For paired UEs, H can be the estimated channels of the paired UEs stacked together.

[0094] At least some of the steps of the proposed method illustrated in Figure 5 will now be described in more detail with respect to Figures 6 to 9.

[0095] Figure 6 illustrates an uplink reference signal resource group allocation according to an embodiment. As shown in Figure 6, there are a plurality of uplink reference signal (e.g. SRS) resources 804, 806, 808. The plurality of uplink reference signal resources 804, 806, 808 are separated into a plurality of groups 800, 802. The plurality of groups comprise at least a first group 800 and a second group 802. The first group 800 is reserved for UEs of a first type (e.g. codebook UEs) and the second group 802 is reserved for UEs of a second type (e.g. reciprocity UEs). The first group 800 comprise a first uplink reference signal resource 804, and the second group 802 comprises a second uplink reference signal resource 806 and a third uplink reference signal resource 808. However, it will be understood that the plurality of resources can comprise any other number of two or more resources, the first group 800 and / or the second group 802 can comprise any other number of resources, and there may be more than two groups.

[0096] Figure 7 illustrates an uplink reference signal resource group allocation according to another embodiment. The plurality of uplink reference signal (e.g. SRS) resources are separated into a plurality of groups in the same way as Figure 6, where the first and second groups 900, 902 of Figure 7 correspond to the first and second groups 800, 802 of Figure 6 and the first and second uplink reference signal resources 904, 906 of Figure 7 correspond to the first and second uplink reference signal resources 804, 806 of Figure 6. However, in the embodiment illustrated in Figure 7, the plurality of uplink reference signal resources are separated in the same way for a plurality of cells (CellO, Celli , Cell2) of the (target) network, or even for all cells of the (target) network.

[0097] For example, for each cell (CellO, Celli , Cell2), the first group 900 comprises the first uplink reference signal resource 904 and the second group 902 comprises the second uplink reference signal resource 906. Thus, the first group 900 is the first uplink reference signal resource 904 and the second group 902 starts from the second uplink reference resource 906.

[0098] In order for the plurality of uplink reference signal resources to be separated in the same way for a plurality of cells, there may be coordination among cells. The coordination may be static, without transferring signals among cells, or the coordination can be semi-static, with signalling transfer among cells. In an example of static coordination, the coordination can be implemented when a cell is set up in the (target) network, and a strategy for separated groups of uplink reference signal resources for different types of UE can be assigned to be the same for all the cells. In an example of semi-static coordination, when a ratio of the different types of UE changes in a cell (e.g. Celli), the allocation of groups of uplink reference signal resources between the different types of UE may be changed. That is, the plurality of uplink reference signal resources may be separated into different groups, e.g. with some uplink reference signal resources being moved from one group to another group. The cell in which the ratio change occurs can send signalling to other cells to trigger the change in the allocation of groups for the whole deployment.

[0099] One example of the types of UE for which the uplink reference signal resource groups are allocated are codebook UEs and reciprocity UEs, as mentioned earlier. However, the techniques described herein are not limited to there being a link between the uplink reference signal resource groups and these particular UE types. There can be a link between the uplink reference signal resource groups and other UE types. In another example, regarding different ways to calculate a downlink transmission precoder, several DL transmission modes (or types) are widely used, e.g. codebook-based downlink transmission, grid of beam (GoB)-based downlink transmission, and reciprocity-based downlink transmission. In a typical network, there may exist a mix of different downlink transmission modes at the same time. In such an example, a separate group of uplink reference signal resources can be determined for each downlink transmission mode. In another example, separate groups of uplink reference signal resources can be determined for UEs with a high throughput priority (‘VIP UEs’) and UEs with a low throughput priority (‘non-VIP UEs’). This can be useful for a specific requirement test.

[0100] Two detailed examples of the uplink reference signal resource group allocation will now be described with reference to Figures 8 and 9. Figure 8 illustrates an uplink reference signal resource group allocation according to another embodiment. The plurality of uplink reference signal (e.g. SRS) resources are separated into a plurality of groups in the same way as Figure 6, where the first and second groups 1000, 1002 of Figure 8 correspond to the first and second groups 800, 802 of Figure 6 and the first and second uplink reference signal resources 1004, 1006 of Figure 8 correspond to the first and second uplink reference signal resources 804, 806 of Figure 6. However, in the embodiment illustrated in Figure 8, the plurality of uplink reference signal resources are separated in the same way for a plurality of cells (CellO, Celli , Cell2) of the (target) network, or even for all cells of the (target) network.

[0101] For example, for each cell (CellO, Celli , Cell2), the first group 1000 comprises the first uplink reference signal resource 1004 and the second group 1002 comprises the second uplink reference signal resource 1006. Thus, the first group 1000 is the first uplink reference signal resource 1004 and the second group 1002 starts from the second uplink reference signal resource 1006. The first group 1000 is reserved for UEs of a first type (e.g. codebook UEs) and the second group 1002 is reserved for UEs of a second type (e.g. reciprocity UEs).

[0102] As illustrated in Figure 8, uplink signalling 1008 for a first UE of the first type can be scheduled on the first uplink reference signal resource 1004. As also illustrated in Figure 8, measuring 1010 can be performed on the first uplink reference signal resource 1004. In some embodiments, the first uplink reference signal resource 1004 can have a first frequency bandwidth. As illustrated in Figure 8, the uplink signalling 1008 for the first UE can be scheduled on a first part of the first frequency bandwidth and the measuring 1010 can be performed on a second part of the first frequency bandwidth.

[0103] In an example where the first UE of the first type is in a first cell (CellO) 1012 served by the first network node, the first uplink reference signal resource may be assigned to at least one other UE of the first type in a second cell (Celli) 1014 served by a second network node of the network. The second cell 1014 may neighbour the first cell 1012. In some embodiments, the first uplink reference signal resource assigned to the at least one other UE may have a second frequency bandwidth, which is different from the first frequency bandwidth. As illustrated in Figure 8, uplink signalling 1016 for the at least one other UE is scheduled on a first part of the second frequency bandwidth. The first part of the second frequency bandwidth is within the second part of the first frequency bandwidth.

[0104] To avoid an uplink reference signal (distress signal) for a UE of the first type colliding between cells, as illustrated in Figure 8, three cell level uplink reference signals (distress signals) are assigned to the UEs of the first type in the corresponding cells. The three cell level uplink reference signals are FDMed between cells. For CellO, the inter-cell interference from UEs of the first type in neighbouring cells can be measured on the first full band (e.g. full frequency bandwidth) uplink reference signal resource, such as by calculating receive signals on the frequency used by neighbouring cells.

[0105] By separating the plurality of uplink reference signal resources into a plurality of groups for different types of UE, the first network node can measure inter-cell interference separately. This makes it feasible to have specific processing for interference measured from UEs of a certain first type (e.g. codebook UEs) in neighbouring cells, which can improve performance of UEs of that first type. For example, with a separate uplink reference signal resource group, the first network node can configure a higher power target for the uplink reference signal (distress signal) for UEs of that first type, and / or interference scaling for interference from UEs of that first type.

[0106] Figure 9 illustrates an uplink reference signal resource group allocation according to another embodiment. The plurality of uplink reference signal (e.g. SRS) resources are separated into a plurality of groups in the same way as Figure 6, where the first and second groups 1100, 1102 of Figure 9 correspond to the first and second groups 800, 802 of Figure 6 and the first and second uplink reference signal resources 1104, 1106 of Figure 9 correspond to the first and second uplink reference signal resources 804, 806 of Figure 6. However, in the embodiment illustrated in Figure 9, the plurality of uplink reference signal resources are separated in the same way for a plurality of cells (CellO, Celli , Cell2) of the (target) network, or even for all cells of the (target) network.

[0107] For example, for each cell (CellO, Celli , Cell2), the first group 1100 comprises the first uplink reference signal resource 1104 and the second group 1102 comprises the second uplink reference signal resource 1106. Thus, the first group 1100 is the first uplink reference signal resource 1104 and the second group 1102 starts from the second uplink reference resource 1106. The first group 1100 is reserved for UEs of a first type (e.g. codebook UEs) and the second group 1102 is reserved for UEs of a second type (e.g. reciprocity UEs).

[0108] As illustrated in Figure 9, uplink signalling 1108 for a first UE of the first type can be scheduled on the first uplink reference signal resource 1104. In some embodiments, the first uplink reference signal resource 1104 can have a first frequency bandwidth. As illustrated in Figure 9, the uplink signalling 1108 for the first UE can be scheduled on the full first frequency bandwidth.

[0109] In an example where the first UE of the first type is in a first cell (CellO) 1112 served by the first network node, the first uplink reference signal resource may be assigned to at least one other UE of the first type in a second cell (Celli) 1114 served by a second network node of the network. The second cell 1114 may neighbour the first cell 1112. In some embodiments, the first uplink reference signal resource assigned to the at least one other UE may have a second frequency bandwidth, which is different from the first frequency bandwidth. As illustrated in Figure 9, uplink signalling 1116 for the at least one other UE is scheduled on the full second frequency bandwidth.

[0110] In the embodiment illustrated in Figure 9, three cell level uplink reference signals (distress signals) are assigned to three cells (CellO, Celli , Cell2) for all UEs of the first type in the corresponding cells. For CellO, the inter-cell interference from the UEs of the first type in the neighbouring cells can be measured on the first full band uplink reference signal resource, e.g. the first uplink reference signal resource 1104.

[0111] In the manner described herein, in contrast to existing techniques, the proposed techniques advantageously separate a pool of uplink reference signal resources into a plurality of different groups for UEs of different types, such as UEs of a first type (e.g. codebook UEs) and UEs of a second type (e.g. reciprocity UEs). This can be referred to as a group allocation. There can also be coordination among cells of the group allocation, which can ensure that the group allocation among cells is aligned. The proposed techniques can involve a criterion to separate the pool of uplink reference signal resources and optionally also coordinate the group allocation among cells. The proposed techniques can involve a criterion to assign uplink reference signal resources from the corresponding groups. The proposed techniques can involve a method that uses a measured uplink inter-cell interference for downlink transmission beam calculation, optionally involving scaling inter-cell interference for different types of UE.

[0112] The techniques described herein can improve throughout in a network. For example, the techniques described herein can improve the downlink throughout for codebook UEs, such as in a multicell deployment.

[0113] Figure 10 shows simulation results of a mean user throughput for codebook UEs for different served traffic loads. The simulation results are for an example involving a 19x3 cells network deployment with 10000 UEs, which transmit with the File T ransfer Protocol (FTP) traffic model 1. The simulation results show that both the existing method described with reference to Figure 5 and the proposed method described with reference to Figure 5 bring gains to codebook UEs compared with a baseline (Reciprocity Aware Interference Transmission (RAIT)). However, the proposed method improves the throughput for codebook UEs by 15% compared with the existing method.

[0114] Figure 11 shows a network node 500 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and / or operable to communicate directly or indirectly with a UE and / or with other network nodes or equipment, in a telecommunication network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and New Radio (NR) NodeBs (gNBs)), radio access network (RAN) nodes, open RAN (O-RAN) nodes or components of an O-RAN node (e.g., O-RAN radio unit (O-RU), O-RAN distributed unit (O-DU), O-RAN central unit (O-CU)).

[0115] Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units, distributed units (e.g., in an O-RAN access node) and / or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

[0116] Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi- cell / multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and / or Minimization of Drive Tests (MDTs).

[0117] The network node 500 comprises processing circuitry 502. The network node 500 may also comprise a memory 504, a communication interface 506, and a power source 508. The network node 500 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 500 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 500 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 504 for different RATs) and some components may be reused (e.g., a same antenna 510 may be shared by different RATs). The network node 500 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 500, for example Global System for Mobile Communications (GSM), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE), New Radio (NR), WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 500.

[0118] The processing circuitry 502 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and / or encoded logic operable to provide, either alone or in conjunction with other network node 500 components, such as the memory 504, to provide network node 500 functionality.

[0119] In some embodiments, the processing circuitry 502 includes a system on a chip (SOC). In some embodiments, the processing circuitry 502 includes one or more of radio frequency (RF) transceiver circuitry 512 and baseband processing circuitry 514. In some embodiments, the radio frequency (RF) transceiver circuitry 512 and the baseband processing circuitry 514 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 512 and baseband processing circuitry 514 may be on the same chip or set of chips, boards, or units.

[0120] The memory 504 may comprise any form of volatile or non-volatile computer-readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), readonly memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and / or any other volatile or non-volatile, non-transitory device-readable and / or computerexecutable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 502. The memory 504 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and / or other instructions capable of being executed by the processing circuitry 502 and utilized by the network node 500. The memory 504 may be used to store any calculations made by the processing circuitry 502 and / or any data received via the communication interface 506. In some embodiments, the processing circuitry 502 and memory 504 is integrated.

[0121] The communication interface 506 is used in wired or wireless communication of signalling and / or data between a network node, access network, and / or UE. As illustrated, the communication interface 506 comprises port(s) / terminal(s) 516 to transmit and receive data, for example to and from a network over a wired connection. The communication interface 506 also includes radio front-end circuitry 518 that may be coupled to, or in certain embodiments a part of, the antenna 510. Radio front-end circuitry 518 comprises filters 520 and amplifiers 522. The radio front-end circuitry 518 may be connected to an antenna 510 and processing circuitry 502. The radio front-end circuitry may be configured to condition signals communicated between antenna 510 and processing circuitry 502. The radio front-end circuitry 518 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 518 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 520 and / or amplifiers 522. The radio signal may then be transmitted via the antenna 510. Similarly, when receiving data, the antenna 510 may collect radio signals which are then converted into digital data by the radio front-end circuitry 518. The digital data may be passed to the processing circuitry 502. In other embodiments, the communication interface may comprise different components and / or different combinations of components.

[0122] In certain alternative embodiments, the network node 500 does not include separate radio front-end circuitry 518, instead, the processing circuitry 502 includes radio frontend circuitry and is connected to the antenna 510. Similarly, in some embodiments, all or some of the RF transceiver circuitry 512 is part of the communication interface 506. In still other embodiments, the communication interface 506 includes one or more ports or terminals 516, the radio front-end circuitry 518, and the RF transceiver circuitry 512, as part of a radio unit (not shown), and the communication interface 506 communicates with the baseband processing circuitry 514, which is part of a digital unit (not shown). The antenna 510 may include one or more antennas, or antenna arrays, configured to transmit and / or receive wireless signals. The antenna 510 may be coupled to the radio front-end circuitry 518 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 510 is separate from the network node 500 and connectable to the network node 500 through an interface or port.

[0123] The antenna 510, communication interface 506, and / or the processing circuitry 502 may be configured to perform any receiving operations and / or certain obtaining operations described herein as being performed by the network node. Any information, data and / or signals may be received from a UE, another network node and / or any other network equipment. Similarly, the antenna 510, the communication interface 506, and / or the processing circuitry 502 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and / or signals may be transmitted to a UE, another network node and / or any other network equipment.

[0124] The power source 508 provides power to the various components of network node 500 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 508 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 500 with power for performing the functionality described herein. For example, the network node 500 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 508. As a further example, the power source 508 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

[0125] Embodiments of the network node 500 may include additional components beyond those shown in Figure 11 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and / or any functionality necessary to support the subject matter described herein. For example, the network node 500 may include user interface equipment to allow input of information into the network node 500 and to allow output of information from the network node 500. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 500. In an example, the first network node referred to herein, the second network node referred to herein, and / or any other network node referred to herein can be configured in the manner shown and / or described with reference to the network node 500. The network node 500 can be configured to perform the operations according to any of the methods disclosed herein in relation to a network node, including the method shown in Figures 4 and / or 5.

[0126] Figure 12 shows a UE 600 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and / or operable to communicate wirelessly with network nodes and / or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle, vehicle-mounted or vehicle embedded / integrated wireless device, etc. Other examples include any UE identified by the Third Generation Partnership Project (3GPP), including a narrow band internet of things (NB-loT) UE, a machine type communication (MTC) UE, and / or an enhanced MTC (eMTC) UE. In an example, the first UE referred to herein, the second UE referred to herein, and / or any other UE referred to herein can be configured in the manner shown and / or described with reference to the UE 600. The UE 600 can be configured to perform the operations according to any of the methods disclosed herein in relation to a UE.

[0127] A UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), orvehicle-to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and / or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0128] The UE 600 includes processing circuitry 602 that is operatively coupled via a bus 604 to an input / output interface 606, a power source 608, a memory 610, a communication interface 612, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 12. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0129] The processing circuitry 602 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 610. The processing circuitry 602 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 602 may include multiple central processing units (CPUs).

[0130] In the example, the input / output interface 606 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 600. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

[0131] In some embodiments, the power source 608 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 608 may further include power circuitry for delivering power from the power source 608 itself, and / or an external power source, to the various parts of the UE 600 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 608. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 608 to make the power suitable for the respective components of the UE 600 to which power is supplied.

[0132] The memory 610 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 610 includes one or more application programs 614, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 616. The memory 610 may store, for use by the UE 600, any of a variety of various operating systems or combinations of operating systems.

[0133] The memory 610 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD- DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a universal SIM (USIM) and / or integrated SIM (ISIM), other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUlCC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card’. The memory 610 may allow the UE 600 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 610, which may be or comprise a device-readable storage medium.

[0134] The processing circuitry 602 may be configured to communicate with an access network or other network using the communication interface 612. The communication interface 612 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 622. The communication interface 612 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 618 and / or a receiver 620 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 618 and receiver 620 may be coupled to one or more antennas (e.g., antenna 622) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0135] In the illustrated embodiment, communication functions of the communication interface 612 may include cellular communication, Wi-Fi communication, low-power wide-area network (LPWAN) communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and / or standards, such as IEEE 802.11 , Code Division Multiplexing Access (CDMA), WCDMA, GSM, LTE, New Radio, Universal Mobile Telecommunications System (UMTS), WiMax, Ethernet, transmission control protocol / internet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

[0136] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 612, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).

[0137] As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

[0138] A UE, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are a device which is or which is embedded in: a connected refrigerator or freezer, a television (TV), a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door / window sensor, a flood / moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an loT device comprises circuitry and / or software in dependence of the intended application of the loT device in addition to other components as described in relation to the UE 600 shown in Figure 12.

[0139] As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and / or measurements, and transmits the results of such monitoring and / or measurements to another UE and / or a network node. The UE may in this case be an machine-to-machine (M2M) device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-loT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0140] In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed. The first UE referred to herein, the second UE referred to herein, and / or any other UE referred to herein can include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

[0141] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and / or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non- computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

[0142] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hardwired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and / or by end users and a wireless network generally.

[0143] Figure 13 shows an example of a communication system 700 in accordance with some embodiments.

[0144] In the example, the communication system 700 includes a telecommunication network 702 that includes an access network 704, such as a radio access network (RAN), and a core network 706, which includes one or more core network nodes 708. The access network 704 includes one or more access network nodes, such as network nodes 710a and 710b (one or more of which may be generally referred to as network nodes 710), or any other similar 3GPP access nodes or non-3GPP access points. Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network 702 includes one or more O-RAN network nodes. An O- RAN network node is a node in the telecommunication network 702 that supports an O- RAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 702, including one or more network nodes 710 and / or core network nodes 708.

[0145] Examples of an O-RAN network node include an open radio unit (O-RU), an open distributed unit (O-DU), an open central unit (O-CU), including an O-CU control plane (O-CU-CP) or an O-CU user plane (O-CU-UP), a RAN intelligent controller (near-real time or non-real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an O-RAN specification). The network node may support a specification by, for example, supporting an interface defined by the O-RAN specification, such as an A1 , F1 , W1 , E1 , E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Moreover, an O-RAN access node may be a logical node in a physical node. Furthermore, an O-RAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an 0-2 interface defined by the O-RAN Alliance or comparable technologies. The network nodes 710 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 712a, 712b, 712c, and 712d (one or more of which may be generally referred to as UEs 712) to the core network 706 over one or more wireless connections.

[0146] Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 700 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 700 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0147] The UEs 712 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 710 and other communication devices. Similarly, the network nodes 710 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 712 and / or with other network nodes or equipment in the telecommunication network 702 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 702.

[0148] In the depicted example, the core network 706 connects the network nodes 710 to one or more hosts, such as host 716. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 706 includes one more core network nodes (e.g., core network node 708) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 708. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF).

[0149] The host 716 may be under the ownership or control of a service provider other than an operator or provider of the access network 704 and / or the telecommunication network 702, and may be operated by the service provider or on behalf of the service provider. The host 716 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

[0150] As a whole, the communication system 700 of Figure 13 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: GSM; UMTS; LTE, and / or other suitable second generation (2G), third generation (3G), fourth generation (4G), fifth generation (5G) standards, or any applicable future generation standard (e.g., sixth generation (6G)); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and / or any LPWAN standards such as LoRa and Sigfox.

[0151] In some examples, the telecommunication network 702 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunication network 702 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 702. For example, the telecommunication network 702 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and / or Massive Machine Type Communication (mMTC)ZMassive loT services to yet further UEs.

[0152] In some examples, the UEs 712 are configured to transmit and / or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 704 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 704. Additionally, a UE may be configured for operating in single- or multi-RAT or multistandard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as Evolved-UMTS Terrestrial Radio Access Network (E-UTRAN) New Radio - Dual Connectivity (EN-DC).

[0153] In the example, the hub 714 communicates with the access network 704 to facilitate indirect communication between one or more UEs (e.g., UE 712C and / or 712D) and network nodes (e.g., network node 710B). In some examples, the hub 714 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 714 may be a broadband router enabling access to the core network 706 for the UEs. As another example, the hub 714 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 710, or by executable code, script, process, or other instructions in the hub 714. As another example, the hub 714 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 714 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 714 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 714 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 714 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy loT devices. The hub 714 may have a constant / persistent or intermittent connection to the network node 710b. The hub 714 may also allow for a different communication scheme and / or schedule between the hub 714 and UEs (e.g., UE 712C and / or 712D), and between the hub 714 and the core network 706. In other examples, the hub 714 is connected to the core network 706 and / or one or more UEs via a wired connection. Moreover, the hub 714 may be configured to connect to an M2M service provider over the access network 704 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 710 while still connected via the hub 714 via a wired or wireless connection. In some embodiments, the hub 714 may be a dedicated hub - that is, a hub whose primary function is to route communications to / from the UEs from / to the network node 710B. In other embodiments, the hub 714 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 710B, but which is additionally capable of operating as a communication start and / or end point for certain data channels. The communication system 700 may comprise the communication network 100. The UEs 712 may comprise the first UE 120 and / or the second UE 125. The network nodes 710 may comprise the first network node 110 and / or the second network node 115.

[0154] There is also provided a computer program comprising instructions which, when executed by processing circuitry (such as the processing circuitry of the first network node described herein), cause the processing circuitry to perform at least part of the method described herein. There is provided a computer program product, embodied on a non-transitory machine-readable medium, comprising instructions which are executable by processing circuitry (such as the processing circuitry of the first network node described herein) to cause the processing circuitry to perform at least part of the method described herein.

[0155] A computer program product of a network node 500 and / or a UE 600 includes a computer readable storage medium (storage or recording medium) storing a computer program comprising computer readable instructions. Computer readable medium of the network node 500 and / or the UE 600, may be a non-transitory computer readable medium, such as, magnetic media (e.g., a hard disk), optical media, memory devices (e.g., random access memory, flash memory), and the like. In some embodiments, the computer readable instructions of computer program are configured such that when executed by processing circuitry 502 and / or the processing circuitry 602, the computer readable instructions cause the network node 500 and / or the UE 600 to perform steps described herein. In other embodiments, the network node 500 and / or the UE 600 may be configured / operable to perform steps described herein without the need for code. That is, for example, the processing circuitry 502 and / or the processing circuitry 602 may consist merely of one or more ASICs. Hence, the features of the embodiments described herein may be implemented in hardware and / or software.

[0156] There is also provided a computer program product comprising a carrier containing instructions for causing processing circuitry (such as the processing circuitry of the first network node described herein) to perform at least part of the method described herein. In some embodiments, the carrier can be any one of an electronic signal, an optical signal, an electromagnetic signal, an electrical signal, a radio signal, a microwave signal, or a computer-readable storage medium. The computer program code mentioned above may be provided, for instance in the form of a data carrier carrying computer program code for performing the embodiments herein when being loaded into the hardware. 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 the first network node, the second network node, the first UE and / or the second UE, and downloaded to the hardware at production, and / or during software updates.

[0157] In some embodiments, the network node functionality described herein can be performed by hardware. Thus, in some embodiments, the first network node described herein can be a hardware entity. However, it will also be understood that optionally at least part or all of the network node functionality described herein can be virtualised. For example, the functions performed by the first network node described herein can be implemented in software running on generic hardware that is configured to orchestrate the client node functionality and / or server node functionality described herein. Thus, in some embodiments, the first network node described herein can be a virtual node. In some embodiments, at least part or all of the network node functionality described herein may be performed in a network enabled cloud. Thus, the method described herein can be realised as a cloud implementation according to some embodiments. The network node functionality described herein may all be at the same location or at least some of the network node functionality may be distributed. It will be understood that at least some or all of the method steps described herein can be automated in some embodiments. That is, in some embodiments, at least some or all of the method steps described herein can be performed automatically. The method described herein can be a computer-implemented method.

[0158] Therefore, as described herein, there are provided improved techniques for assigning an uplink reference signal resource.

[0159] It should be noted that the above-mentioned embodiments illustrate rather than limit the idea, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim, “a” or “an” does not exclude a plurality, and a single processor or other unit may fulfil the functions of several units recited in the claims. Any reference signs in the claims shall not be construed so as to limit their scope.

Claims

CLAIMS1 . A method for assigning an uplink reference signal resource, wherein the method is performed by a first network node of a network, the method comprising: assigning (102, 302) a first uplink reference signal resource (804, 904, 1004, 1104) to a first UE of a first type, wherein a plurality of uplink reference signal resources are separated into a plurality of groups comprising at least a first group (800, 900, 1000, 1100) and a second group (802, 902, 1002, 1102), wherein the first group (800, 900, 1000, 1100) is reserved for UEs of the first type and the second group (802, 902, 1002, 1102) is reserved for UEs of a second type, and wherein the first uplink reference signal resource (804, 904, 1004, 1104) is selected from the first group (800, 900, 1000, 1100).

2. A method as claimed in claim 1 , wherein: at least one other UE of the first type is assigned the same first uplink reference signal resource as the first UE.

3. A method as claimed in claim 1 or 2, wherein: the first uplink reference signal resource (804, 904, 1004, 1104) is a first sounding reference signal resource or a first uplink demodulation reference signal resource.

4. A method as claimed in any of the preceding claims, the method comprising: changing the first uplink reference signal resource (804, 904, 1004, 1104) assigned to the first UE to a second uplink reference signal resource in response to the first UE changing from the first type to the second type, wherein the second uplink reference signal resource is selected from the second group (802, 902, 1002, 1102).

5. A method as claimed in claim 4, wherein: the second uplink reference signal resource is a second sounding reference signal resource or a second uplink demodulation reference signal resource.

6. A method as claimed in any of the preceding claims, the method comprising: assigning a third uplink reference signal resource (806, 906, 1006, 1106) to a second UE of the second type, wherein the third uplink reference signal resource (806, 906, 1006, 1106) is selected from the second group (802, 902, 1002, 1102).

7. A method as claimed in claim 6, wherein: the third uplink reference signal resource is a third sounding reference signal resource or a third uplink demodulation reference signal resource.

8. A method as claimed in claim 6 or 7, the method comprising: changing the third uplink reference signal resource (806, 906, 1006, 1106) assigned to the second UE to a fourth uplink reference signal resource in response to the second UE changing from the second type of UE to the first type of UE, wherein the fourth uplink reference signal resource is selected from the first group (800, 900, 1000, 1100).

9. A method as claimed in claim 8, wherein: the fourth uplink reference signal resource is a fourth sounding reference signal resource or a fourth uplink demodulation reference signal resource.

10. A method as claimed in any of the preceding claims, the method comprising: separating (300) the plurality of uplink reference signal resources into the plurality of groups.

11. A method as claimed in any of the preceding claims, wherein: the second group comprises more of the plurality of uplink reference signal resources than the first group comprises.

12. A method as claimed in any of the preceding claims, the method comprising: changing the plurality of groups in response to a change in a ratio of the UEs of the first type and the UEs of the second type.

13. A method as claimed in any of the preceding claims, the method comprising one or both of: reserving the first group (800, 900, 1000, 1100) for UEs of the first type; and reserving the second group (802, 902, 1002, 1102) for UEs of the second type.

14. A method as claimed in any of claims 1 to 12, wherein: the first network node is configured with information indicative of the plurality of groups.

15. A method as claimed in claim 14, wherein: the first network node is configured with the information when a cell to be served by the first network node is set up in the network.

16. A method as claimed in any of the preceding claims, the method comprising: informing at least one second network node of the network about the plurality of groups.

17. A method as claimed in claim 16, wherein: informing at least one second network node of the network comprises: informing all other network nodes of the network; or informing each network node of the network that is configured to serve a cell neighbouring a cell that the first network node is configured to serve.

18. A method as claimed in any of the preceding claims, wherein: the first UE is classified as the first type based on a downlink channel quality that the first UE has.

19. A method as claimed in any of the preceding claims, the method comprising one or both of: scheduling (304) uplink signalling (1008, 1108) for the first UE on the first uplink reference signal resource (1004, 1104); and performing (304) measuring (1010) on the first uplink reference signal resource (1004).

20. A method as claimed in claim 19, wherein:the first uplink reference signal resource (804, 904, 1004, 1104) has a first frequency bandwidth.

21. A method as claimed in claim 20, when claim 19 is directly or indirectly dependent on claim 6, wherein: the third uplink reference signal resource (806, 906, 1006, 1106) has the same frequency bandwidth as the first uplink reference signal resource (804, 904, 1004, 1104).

22. A method as claimed in claim 20 or 21 , wherein: the uplink signalling (1008) for the first UE is scheduled on a first part of the first frequency bandwidth and the measuring (1010) is performed on a second part of the first frequency bandwidth; or the uplink signalling (1108) for the first UE is scheduled on the full first frequency bandwidth.

23. A method as claimed in any of claims 20 to 22, wherein: the first UE is in a first cell (1012) served by the first network node; and the first uplink reference signal resource is assigned to at least one other UE of the first type in a second cell (1014) served by a second network node of the network, wherein the second cell (1014) neighbours the first cell (1012).

24. A method as claimed in claim 23, wherein: the first uplink reference signal resource assigned to the at least one other UE has a second frequency bandwidth, and the second frequency bandwidth is different from the first frequency bandwidth.

25. A method as claimed in claim 24, when claim 23 is dependent on claim 22, wherein: uplink signalling (1016) for the at least one other UE is scheduled on a first part of the second frequency bandwidth; and the first part of the second frequency bandwidth is within the second part of the first frequency bandwidth.

26. A method as claimed in claim 24, wherein:uplink signalling (1116) for the at least one other UE is scheduled on the full second frequency bandwidth.

27. A method as claimed in any of the preceding claims, wherein:UEs of the first type are UEs that are served using a first downlink transmission mode and UEs of the second type are UEs that are served using a second downlink transmission mode; orUEs of the first type are UEs that are assigned a first priority and UEs of the second type are UEs that are assigned a second priority.

28. A method as claimed in claim 27, wherein: the first downlink transmission mode uses a codebook based downlink transmission; and the second downlink transmission mode uses a non-codebook based downlink transmission.

29. A method as claimed in claim 28, wherein: the non-codebook based downlink transmission is a reciprocity based downlink transmission or a grid of beam, GoB, downlink transmission.

30. A first network node (500) comprising processing circuitry (502) configured to cause the first network node (500) to: assign a first uplink reference signal resource to a first UE of a first type, wherein a plurality of uplink reference signal resources are separated into at least a first group and a second group, wherein the first group is reserved for UEs of the first type and the second group is reserved for UEs of a second type, and wherein the first uplink reference signal resource is selected from the first group.31 . A first network node (500) as claimed in claim 30, wherein: the processing circuitry (502) is configured to cause the first network node (500) to perform the method according to any of claims 2 to 29.

32. A computer program comprising instructions which, when executed by processing circuitry, cause the processing circuitry to perform the method according to any of claims 1 to 29.

33. A computer program product, embodied on a non-transitory machine-readable medium, comprising instructions which are executable by processing circuitry to cause the processing circuitry to perform the method according to any of claims 1 to 29.

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