WO2020192901A1

WO2020192901A1 - Technique for controlling radio resource allocation

Info

Publication number: WO2020192901A1
Application number: PCT/EP2019/057636
Authority: WO
Inventors: Roberto ANTONIOLI; Jonas Pettersson
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2019-03-26
Filing date: 2019-03-26
Publication date: 2020-10-01

Abstract

A technique for controlling an allocation of radio resources in a radio access network, RAN (300), is described. The RAN (300) is configured to provide multi-connectivity to a radio device (308-12) through multiple cells (306-1, 306-2) each associated (305-1; 305-2) with a resource allocator, RA (304-1; 304-2). The RA (304-1; 304-2) is configured to allocate radio resources to the radio device (308-12) in the respective cell (306-1; 306-2). Each RA (304-1; 304-2) is associated (303-1; 303-2) with a resource regulator, RR (100-1; 100-2), configured to control the allocation of the respective radio resources by the respective RA (304-1; 304-2) to the radio device (308-12) according to a share of the respective radio resources in the respective cell (306-1; 306-2). As to a method aspect of the technique, a first control information (310-1) from a second RR (100-2) associated (303-2) with a second RA (304-2) associated (305-2) with a second cell (306-2) of the multi-connectivity is received at a first RR (100-1) associated with a first RA (304-1) associated (305-1) with a first cell (306-1) of the multi-connectivity. The first control information (310-1) is indicative of second radio resources (312-2) allocated to the radio device in the second cell. The allocation of first radio resources (312-1) to the radio device (308-12) in the first cell (306-1) is controlled by computing the share of the first radio resources in the first cell (306-1) depending on the second radio resources (312-2). A second control information (310-2) is sent from the first RR (100-1) to the second RR (100-2). The second control information (310-2) is indicative of the first radio resources (312-1) resulting from the computed share.

Description

TECHNIQUE FOR CONTROLLING RADIO RESOURCE ALLOCATION

Technical Field

The present disclosure relates to an allocation of radio resources in a radio access network, RAN. More specifically, and without limitation, methods and devices are provided for controlling an allocation of radio resources in a RAN that is multiply connected to a radio device.

Background

Radio access networks (RANs) for mobile communication comprise many components that have made them such a success for how people communicate and retrieve information. For example, RANs that operate according to radio access technologies (RATs) specified by the Third Generation Partnership Project (3GPP), such as High Speed Downlink Packet Access (HSDPA), High Speed Packet Access (HSPA), Long Term Evolution (LTE) and Fifth Generation (5G) New Radio (NR), provide not only high data throughput to single radio device (e.g., a single user) but also high capacity in terms of serving many radio devices (e.g., many users) simultaneous with a sufficient bit rate and a reasonable packet latency.

One of the key components of the RAN is the medium access control (MAC) scheduler, which sits above the physical layer. The MAC scheduler allocates radio resources to the radio devices (e.g., User Equipments, or UE) and is thus

responsible for deciding how uplink and downlink channels are used by a base station and the radio devices in a cell served by the base station. A target of the allocation is to maximize the overall performance of the RAN. This performance target can contain many aspects, and the most fundamental is often the bit rate experienced by the individual radio devices. It is not only the total aggregated bit rate that is important for the overall performance. The relation of the bit rates allocated to different radio devices is equally important, which may be referred to as fairness.

In the case of multi-connectivity, a radio device is connected to multiple cells of the RAN. As compared to single-connectivity, multi-connectivity makes it harder to achieve both performance targets and fairness, since the bit rate for each scheduled radio device no longer depends only on the allocation decisions of the MAC scheduler of a single cell.

A first approach to handle multi-connectivity is to schedule each cell of the RAN independently, i.e., without considering radio resources that the RAN allocates to the radio devices in one or more (e.g., overlapping) other cells. Such well-known scheduling algorithms are described in "Downlink Packet Scheduling in LTE Cellular Networks: Key Design Issues and a Survey" by F. Capozzi, G. Piro, L.A. Grieco, G. Boggia, P. Camarda, IEEE Communication Surveys & Tutorials, Vol. 15, No. 2, 2013. All of the described scheduling algorithms schedule each cell independently.

However, scheduling each cell individually leads to an unfair or unpredictable distribution of radio resources between different cells.

Another approach to handle multi-connectivity is to run an existing MAC scheduler in a centralized fashion so that the single MAC scheduler handles all the involved cells, e.g., as described in "Learning radio resource management in 5G networks: Framework, opportunities and challenges" by F. D. Calabrese, L. Wang, E. Ghadimi, G. Peters, and P. Soldati, IEEE Communications Magazine, Vol. 56, No. 9, Sep 2018; "Multiobjective Subchannel and Power Allocation in Interference-Limited Two-Tier OFDMA Femtocell Networks" by N. Sharma, D. Badheka, A. Anpalagan, IEEE Systems Journal, Vol. 10, No. 5, Jun 2016; and "Resource Allocation and

Multisession Routing Algorithms in Coordinated Multipoint Wireless

Communication Networks" by F. Y. Lin, Y. Wen, L. Fang, C. Hsiao, IEEE Systems Journal, Vol. 12, No. 3, Sep 2018. The bit rates of the individual radio devices are then controlled by the single scheduler, even if served by multiple cells. In some cases, it is possible to treat the radio resources as a single pool even if they belong to different cells. However, a completely centralized scheduler can consider all the assignments of radio resource but presents at least the two following problems. Firstly, a lot of information (e.g., the full scheduling decisions) needs to be transferred with very short latency between the base stations and the centralized MAC scheduler. Secondly, the amount of processing required in the centralized scheduler becomes very high and scales badly (e.g., quadratically) with the number of involved transmission points.

Furthermore, an existing approach to multi-connectivity scheduling is to let multiple MAC scheduler exchange information to achieve a preferred overall allocation decision. An example of such an approach is presented in the document "Carrier load balancing and packet scheduling for multi-carrier systems" by Yuanye Wang, Klaus I. Pedersen, Troels B. Sorensen, and Preben E. Mogensen, IEEE Transactions on Wireless Communications, Vol. 9, No. 5, May 2010. In this document, a cross-carrier proportional fairness MAC scheduler is proposed for multi-connectivity. Other examples of decentralized approaches are presented in the documents "Distributed RRM for 5G Multi-RAT Multiconnectivity Networks" by V. F. Monteiro, D. A. Sousa, T. F. Maciel, F. R. P. Cavalcanti, C. F. M. Silva, E. B. Rodrigues, IEEE Systems Journal, Early Access, Jun 2018; "Energy-Aware

Cooperative Traffic Offloading via Device-to-Device Cooperations: An Analytical Approach" by Y. Wu, J. Chen, L. P. Qian, J. Fluang, X. S. Shen, IEEE Transactions on Mobile Computing, Vol. 16, No.l, Jan 2017; and "Distributed Resource Allocation in 5G Cellular Networks" by M. Hasan, E. Hossain, Sep 2017, published on

arxiv.org/abs/1409.2475.

Moreover, a further existing approach involves the radio device to assist the MAC schedulers on deciding how the radio device should be scheduled across multiple connections, e.g., as presented in the documents "Optimal traffic aggregation in multi-RAT heterogeneous wireless networks" by Sarabjot Singh, Shu-pin Yeh, Nageen Himayat, and Shilpa Talwar, IEEE International Conference on

Communications - Workshops 2016; "Dynamic Network Selection in

Heterogeneous Wireless Networks: A user-centric scheme for improved delivery" by A. Awad, A. Mohamed, C. F. Chiasserini, IEEE Consumer Electronics Magazine, Vol. 6, No. 1, Jan 2017; and "Secrecy-Based Energy-Efficient Data Offloading via Dual Connectivity Over Unlicensed Spectrums" by Y. Wu, K. Guo, J. Huang, X. S. Shen, IEEE Journal on Selected Areas in Communications, Vol. 34, No. 2, Dec 2016.

However, the existing distributed schedulers for multi-connectivity scenarios also require a lot of data exchange with low latency between the distributed MAC scheduler entities or between the radio devices and the scheduler entities.

In conclusion, the existing centralized or distributed MAC schedulers are sensitive to latency and might behave badly if the communication (e.g., a backhaul communication) between the involved entities is delayed. Also, since the existing distributed schedulers are based on the traditional MAC schedulers, adding new scheduler behaviors for multi-connectivity is a difficult process, e.g., because it is hard to predict the effects of even small changes. For example, a weights-based method of handling both service or application aspects and radio aspects is difficult to optimize and to verify due to the large number of possible combinations of these two aspects.

Summary

Accordingly, there is a need for a technique that controls an allocation of radio resources in a RAN providing multi-connectivity to at least one radio device.

As to a first method aspect, a method of controlling an allocation of radio resources in a radio access network (RAN) is provided. The RAN is configured to provide multi-connectivity to a radio device through multiple cells. Each of the cells is associated with a resource allocator (RA) configured to allocate radio resources to the radio device in the respective cell. Each RA is associated with a resource regulator (RR) configured to control the allocation of the respective radio resources by the respective RA to the radio device according to a share of the respective radio resources in the respective cell. The method comprises or initiates a step of receiving, at a first RR associated with a first RA associated with a first cell of the multi-connectivity, a first control information from a second RR associated with a second RA associated with a second cell of the multi-connectivity. The first control information is indicative of second radio resources allocated to the radio device in the second cell. The method further comprises or initiates a step of controlling the allocation of first radio resources to the radio device in the first cell by computing the share of the first radio resources in the first cell depending on the second radio resources. The method further comprises or initiates a step of sending, from the first RR, a second control information to the second RR. The second control information is indicative of the first radio resources resulting from the computed share.

In at least some embodiments, the communication between the RRs (e.g., the transmitting and/or receiving steps) enables the first RR (or each of the RRs) to take the multi-connectivity into account when the first RR (or each RR) controls (e.g., determines or decides) the share of the radio resource allocated to the radio device by its controlled one or more RAs. For example, the first RR may control the share of the first radio resources allocated by the first RA to the radio device depending on the received first control information. Thereby, the first and second RRs (or all RRs) of the RAN may arrive at a more suitable and fair relative resource shares overall. In same or further embodiments, the RR and the RA associated with any one of the cells of the RAN may provide the functionality of a distributed scheduler in the presence of the multi-connectivity by virtue of the communication (e.g., the transmitting and receiving steps) between the RRs controlling different RAs providing the multi-connectivity.

In the case of multi-connectivity, one radio device may be multiply connected to the RAN, for example the radio device is connected to multiple cells including the first cell and the second cell.

The share computed by the first RR (or each RR involved in the multi-connectivity of the radio device) for the radio device may be a relative share of the first radio resources (or the respective radio resources) allocated by the first RA (or the RA associated with the respective RR) to the radio device among all radio resources allocated by the first RA (or the respective RA) in the first cell (or in the respective cell). Alternatively or in addition, the share computed by the first RR (or each RR involved in the multi-connectivity of the radio device) for the radio device may be a relative share of the first radio resources (or the respective radio resources) allocated by the first RA (or the RA associated with the respective RR) to the radio device among all radio resources allocated by all RAs associated with the first RR (or the respective RR).

The step of controlling the allocation of the first radio resources in the first cell may comprise signaling the computed share to the first RA. The first RA may allocate the first radio resources to the radio device in the first cell according to the signaled share.

The first RA may allocate the first radio resources to the radio device in a first cell of the multi-connectivity. The second RA may allocate the second radio resources to the radio device in a second cell of the multi-connectivity. Any one of the cells referred to or described herein may comprise or may be implemented by a transmission and reception point (TRP) or a base station (BS).

A functionality (i.e., a responsibility) of a scheduler for the RAN may be split into the RA and the RR. The RA and the RR may also be referred to as a split- responsibility scheduler. In other words, the scheduler of each cell in the RAN may be jointly implemented by the RR and the RA associated with the respective cell. The RAN may provide radio access (e.g., single-connectivity and/or multi connectivity) to a plurality of radio devices. The RAN may provide multi

connectivity to at least one of the plurality of radio devices, which is generically referred to as "the radio device".

The information exchange (e.g., the transmitting and receiving steps) may be defined and/or implemented in an interface or an application protocol handling signaling related to the multi-connectivity (e.g., dual connectivity). For example, the information exchange may be defined and/or implemented in an interface for backhaul communication between cells (i.e., base stations or TRPs), e.g., Xn in an NR implementation of X2 in an LTE implementation, and/or in an application protocol for the backhaul communication between the cells, e.g., XnAP in the NR implementation of X2AP in the LTE implementation. The RR, the RA and/or the splitting of the scheduler of the RAN may be standardized for 3GPP radio access technologies (RATs), e.g., for 3GPP New Radio (NR) and/or 3GPP Long Term

Evolution (LTE).

By means of the respective control information exchanged between the first and second RRs (i.e., the transmitting and receiving steps), the first RR (or each of the first and second RRs) may determine the radio resources (e.g., a bit rate) that is offered to the radio device in multi-connectivity by one or more other RRs (e.g., the second RR), e.g., on legs of the multi-connectivity (e.g., on a second leg of the multi-connectivity allocated by the second RA) other than a first leg of the multi connectivity, which is controlled by the first RR.

In the controlling step, the first control information may be used for computing the share of the first radio resources that are allocated or that are to be allocated to the radio device (e.g., a relative share of the first radio resources among all radio resources allocated or allocatable in the first cell) by the first RA controlled by the first RR. For example, an updated bit rate may be computed, which is signaled to and/or applied by the first RA and/or sent to the one or more other RRs (e.g., the second RR) by means of the second control information.

The second control information may trigger a controlling step at the second RR for computing a second share that is to be allocated to the radio device by the second RA controlled by the second RR. That is, the process may start over, e.g., by the second RR performing the method, wherein the second control information transmitted by the first RR is the first control information received at the second RR, and/or the second control information transmitted by the second RR is a further first control information received at the first RR.

A total available share of the radio resources allocated or allocatable by the first RA (i.e., 100% of resource share relative to the first RA) may be divided into a plurality of step shares. The total share for the first RA may be partitioned into the plurality of step shares. Each of the step shares may be a fraction and/or unit of the total available share. The computed share (and/or each of the one or more computed further shares) may be defined in units and/or combinations of the step shares. Alternatively or in addition, the computed share (and/or each of the one or more computed further shares) may be defined as an integer multiples of the step share (i.e., for equally sized step shares).

Step shares may be defined in relation to each RA of the RAN, used for computing a corresponding share at each RR of the RAN and/or for controlling the respective RA by each RR of the RAN.

In the controlling step of the method, i.e., by computing the share, the first RR may deploy and/or perform an algorithm that determines how to distribute one or more step shares among the radio device and one or more further radio devices allocated by the first RA. The algorithm may use the first control information (e.g., indicative of the second radio resources allocated by the second RA and optionally third radio resources allocated by a third RA) from one or more other RRs (e.g., from the second RR associated with the second RA and optionally a third RR associated with the third RA) and local information (e.g., information as to the first radio resources allocated by the first RA).

The algorithm computing the share may control a reallocate of the first radio resources by changing the share of the first radio resources. The algorithm may move (i.e. reallocate) one or more step shares (e.g., corresponding to a portion of first radio resources previously allocated to the radio device) from the radio device to another radio device (e.g., one of the further radio devices). The algorithm move a step share if a criterion is fulfilled. The criterion may require that moving the step share increases (or is estimated to increase) a utility of a system according to (e.g., predefined) utility functions. The system may comprise the radio device and the one or more further radio devices (e.g., all radio devices allocated by the first RA) and/or the RAN. The algorithm converges to a stable solution from which a share refinement might be needed to balance the number of users in multi connectivity.

The corresponding method, particularly the algorithm, may be performed by each RR of the RAN.

The target of optimizing both the overall performance of the RAN and the bit rate experienced by the individual radio devices may be controlled in terms of one or more utility functions that are defined so that the wanted system behavior is achieved when the utility (i.e., the value of the utility function) is maximized.

In contrast to conventionally scheduling the cells of a RAN independently, the technique may be implemented by controlling the allocation of radio resources (e.g., by controlling the scheduling) based on the exchanged information (i.e., the first and/or second control information). The information exchange (i.e., the receiving and/or transmitting steps) between the RRs of the RAN may increase the utility function for the radio devices served by the RAN, may optimize the performance of the RAN (e.g., from the perspective of all radio devices served by the RNA), and/or may lead to predictable fairness between the radio devices (e.g., users) served by the RAN, e.g., since the radio resources in the first cell often are worth less to a radio device (e.g., a user) that is allocated many radio resources in another cell (e.g., the second cell) by another RA (e.g., the second RA) than to one or more further radio devices (e.g., a further users) that only get radio resources in the first cell from the first RA.

The first RR may perform the method. The first RR may be the RR that is configured to control the allocation of the first radio resources to the radio device by the first RA in the first cell of the multi-connectivity. The second RR may be the RR that is configured to control the allocation of the second radio resources to the radio device by the second RA in the second cell of the multi-connectivity.

Each RA (e.g., each of the RAs involved in the multi-connectivity or each of the RAs in the RAN) may be associated with a different one of the RRs.

Each RR may be embodied by a node of the RAN, e.g., a radio access node such as a base station (BS), a transmission and reception point (TRP) or an access point (AP). Said node may further embody the RA or the multiple RAs associated with the respective RR.

Each RA may be configured to at least one of receive channel state information (CSI) in the associated cell, perform or initiate a retransmission of a packet data unit (PDU) previously transmitted to the radio device, and/or perform link adaptation in the associated cell.

The multi-connectivity may be a dual-connectivity (DC). Alternatively or in addition, more than two cells (including the first and second cells) may provide the multi-connectivity to the radio device, i.e., more than the first and second RAs as well as more than the associated first and second RRs may be involved in the multi-connectivity of the radio device.

The multi-connectivity may be a state of the radio device. For example, the multi connectivity may be a radio resource control (RRC) state of the radio device.

Any one of the cells of the multi-connectivity (i.e., any one of the cells involved in the connectivity of the radio device), the RA associated with the one cell and the RR associated with the RA may be collectively referred to as a leg of the multi connectivity. That is, the DC may comprise a first leg and a second leg. The multi connectivity may comprise the first leg, the second leg and, optionally, further legs. The first leg may comprise the first cell, the first RA and the first RR. The second leg may comprise the second cell, the second RA and the second RR.

In the case of more than two RRs being involved in the multi-connectivity of the radio device, the first control information may be received from the second RR and from a third RR involved in the multi-connectivity of the radio device. The first control information received from the second RR may be indicative of the second radio resources allocated to the radio device by the second RA associated with the second RR. The first control information received from the third RR may be indicative of third radio resources allocated to the radio device by a third RA associated with the third RR.

The exchanged control information (e.g., the first and/or second control information) may be specific for the radio device or may be indicative of radio resources allocated specifically to the radio device. For example, the exchanged control information may list identifiers of radio devices in combination with radio resources allocated to the respective radio devices.

The step of controlling the allocation may comprise sending, the to the first RA, at least one of the computed share and allocation control information indicative of the first radio resources according to the computed share. The computed share or the allocation control information may be sent in association with an identifier of the radio device. The first RA may perform the allocation of the radio resources according to the received share or allocation control information and/or responsive to receiving the share or allocation control information. Performing the allocation of the radio resources may comprise scheduling the radio resources, particularly transmitting at least one of a scheduling grant and a scheduling assignment.

The first control information may comprise a potential of the second radio resources. Alternatively or in addition, the second control information may comprise a potential of the first radio resources.

The potential of the respective radio resources may be specific for the radio device. Alternatively or in addition, the potential of the respective radio resources may depend on a radio quality of a radio link for the radio device in the respective cell.

Herein, the radio quality of the respective radio link for the respective radio device may also be referred to as link quality or channel quality, or briefly as quality.

The potential of the respective radio resources may depend on a signal-to-noise ratio, SNR, a signal-to-interference-and-noise ratio, SINR, and/or a path loss of the respective radio resources of the radio link used by the radio device in the respective cell. The radio link may be a downlink from a base station serving the respective cell to the radio device.

The potential of the respective radio resources may comprise at least one of a channel capacity of the respective radio resources and a number of bits or a bit rate of the respective radio resources. Herein, an amount of the respective radio resources may encompass a bandwidth and/or a quantity of the respective radio resources, e.g., a number of physical resource blocks (PRBs) and/or a number of subframes, transmission time intervals (TTIs) or symbols. The potential and the amount of the respective radio resources may be related by a quality of the respective radio resources, e.g., according to:

Potential = Amount · Quality.

The potential and the amount of the respective radio resources may be related by a Shannon-Hartley theorem. The quality, and as a consequence the potential, may be specific for the radio device. The quality may depend on the SNR at the radio device according to

Quality = log (1+SNR).

The share may be computed using a utility function for the radio device. The utility function for the radio device may depend on both the first radio resources and the second radio resources. For example, the utility function for the radio device may depend on the potential of the first radio resources and the potential of the second radio resources.

The share of the first radio resources in the first cell may be computed by the first RR using the utility function for the radio device. The utility function for the radio device may depend on both the first radio resources and the second radio resources allocated to the radio device in the first cell and the second cell, respectively.

The utility function for the radio device may depend on all radio resources allocated to the radio device in all cells of the multi-connectivity. For more than two cells (including the first and second cells) providing the multi-connectivity to the radio device, the utility function for the radio device may depend on both the first radio resources (e.g., according to the share of the first radio resources for the radio device in the first cell), the second radio resources allocated to the radio device in the second cell (e.g., according to the first control information received from the second RR) and the third radio resources allocated to the radio device in the third cell (e.g., according to the first control information received from the third RR). The utility function for the radio device may further depend on a quality of service (QoS) requirement or a QoS class indicator (QCI) of the radio device.

The utility function for the radio device may depend on the sum of the first radio resources and the second radio resources. The utility function for the radio device may depend on the sum of all radio resources allocated to the radio device in the cells of the multi-connectivity, including the first radio resources and the second radio resources. Alternatively or in addition, the utility function for the radio device may depend on the sum of the potential of the first radio resources and the potential of the second radio resources. The utility function for the radio device may depend on the sum of the potentials of all radio resources allocated to the radio device in the cells of the multi-connectivity, including the potential of the first radio resources and the potential of the second radio resources.

The share may be computed by increasing or maximizing the sum of the utility function for the radio device and one or more further utility functions for one or more further radio devices, to each of which further first radio resources in the first cell are allocated by the first RA.

The one or more further radio devices may comprise at least one further radio device or all further radio devices allocated (e.g., scheduled) by the first RA, e.g., served using the first cell. At least one or each of the one or more further radio devices may be in single-connectivity or multi-connectivity to the RAN. That is, each of the one or more further radio devices may be connected through at least the first cell and/or allocated (e.g., scheduled) by at least the first RA. Optionally, at least one or each of the one or more further radio devices may be further radio- connected through one or more cells other than the first cell (e.g., through the second cell) and/or allocated (e.g., scheduled) by one or more RAs other than the first RA (e.g., by the second RA).

The first radio resources are variable for the increasing or maximizing.

Alternatively or in addition, the second radio resources are fixed for the increasing or maximizing. The share of the first radio resources for the radio device may be changed, e.g., in discrete steps (also referred to as step shares) for the increasing or maximizing of the sum of the utility function and the at least one further utility function.

Moreover, the sum of all radio resources allocated (or allocatable by controlling the allocation) in the first cell may be fixed for the increasing or maximizing. That is the first radio resources and the further first radio resources may be constant for the increasing or maximizing. For example, the share of the first radio resources in the first cell may be increased or decreased in conjunction with equally decreasing or increasing, respectively, a further share of the further first radio resources in the first cell.

The share for the radio device may be increased by a step share, if an increment of the utility function for the radio device due to the step share is greater than a decrement of one of the at least one further utility function for the respective further radio device due to decreasing a further share of the respective further first radio resources for the respective further radio device by the step share. Vice verso, the share may be decreased for the radio device by a step share, if a decrement of the utility function for the radio device due to the step share is less than an increment of one of the at least one further utility function for the respective further radio device due to increasing a further share of the respective further first radio resources for the respective further radio device by the step share.

The share may be increased for the radio device by the step share, if the increment of the utility function for the radio device due to the step share is greater than an increment of each of the at least one further utility function due to increasing a respective further share of the respective further first radio resources for the respective further radio device by the step share. Vice verso, the share may be decreased for the radio device by the step share, if the decrement of the utility function for the radio device due to the step share is less than a decrement of each of the at least one further utility function due to decreasing a respective further share of the respective further first radio resources for the respective further radio device by the step share.

A radio device whose share of radio resources in the first cell is decreased may also be referred to as a resource donator in the first cell (or briefly: donator). A radio device whose share of radio resources in the first cell is increased may also be referred to as a resource receiver in the first cell (or briefly: receiver). Radio resources in the first cell, which are no longer allocated to the donator, may correspond to radio resources in the first cell, which are allocated additionally to the receiver. These radio resources in the first cell may be referred to as reallocated by the first RA.

Each further utility function for the respective further radio device may depend on the respective further first radio resources allocated to the respective further radio device in the first cell. For example, each further utility function for the respective further radio device may depend on a potential of the respective further first radio resources.

Each of the at least one further utility function for the respective further radio device may depend on the further first radio resources allocated to the respective further radio device according to the respective further share.

The RAN may be configured to provide multi-connectivity to at least one of the one or more further radio devices using the first cell and the second cell. The first control information received from the second RR may further be indicative of further second radio resources allocated to the at least one of the one or more further radio devices by the second RA associated with the second RR.

Alternatively or in addition, the second control information sent to the second RR may further be indicative of the respective further first radio resources allocated to the at least one of the one or more further radio devices by the first RA associated with the first RR.

The RAN may be configured to provide multi-connectivity to at least one of the one or more further radio devices using the first cell and a third cell associated with a third RA associated with a third RR. The method may further comprise or initiate a step of receiving, at the first RR, a further first control information from the third RR, the further first control information being indicative of further second radio resources allocated to the at least one of the one or more further radio devices by the third RA associated with the third RR. Alternatively or in addition, the method may further comprise or initiate a step of sending, from the first RR, a further second control information to the third RR, the further second control information being indicative of the respective further first radio resources allocated to the at least one of the one or more further radio devices by the first RA associated with the first RR.

The third cell may be different from the first and second cells. The third RA may be different from the first and second RAs. The third RR may be different from the first and second RRs.

The first control information and/or the further first control information may comprise a potential of the further second radio resources. Alternatively or in addition, the second control information and/or the further second control information comprises a potential of the further first radio resources.

The potential of the respective radio resources may be specific for the respective further radio device and/or may depend on a radio quality of a radio link for the respective further radio device in the respective cell.

The potential of the respective radio resources may comprise at least one of a channel capacity of the respective further radio resources and a number of bits or a bit rate of the respective radio resources.

Each further utility function for the respective one of the one or more further radio devices further may depend on the respective further second radio resources allocated to the respective further radio device, preferably each further utility function for the respective one of the one or more further radio devices further depends on a potential of the respective further second radio resources allocated to the respective further radio device.

Each of the at least one further utility function for the respective further radio device may depend on the further first radio resources allocated to the respective further radio device according to the respective further share and the further second radio resources allocated to the respective further radio device according to the first control information and/or the further first control information.

The controlling step may further comprise controlling the allocation of the respective further first radio resources to the respective further radio device in the first cell by computing the further share of the respective further first radio resources in the first cell depending on the respective further second radio resources. For example, the share for the radio device and the respective further share for the respective further radio device may be computed iteratively by increasing (or decreasing) the share by the step share and decreasing (or increasing) the respective further share by the step share to increase or maximize the sum of the utility function and the one or more further utility functions.

For each radio device allocated (e.g., scheduled) by the first RA, the first RR may compute a share of the radio resources allocated to respective radio device. If no second control information is available for the respective radio device (e.g., because the radio device is in single-connectivity with the RAN only through the first cell), the share may be computed based on a utility as a function of the radio resources allocated to the respective radio device only by the first RA in the first cell. If the second control information is available for the respective radio device (e.g., because the radio device is in multi-connectivity with the RAN including the first cell and the second cell), the share may be computed based on the utility as a function (i.e., a utility function) of both the first radio resources and the second radio resources. That is, the utility function may be a function of the radio resources allocated to the respective radio device by both the first RA in the first cell and the second RA in the second cell.

At least one or each of the utility function and the further utility function may be non-linear.

The received first control information may indicate an offset (e.g., due to the second radio resources) in the sum of radio resources (e.g., the sum of bit rates) allocated to the respective radio device when controlling the first radio resources for the radio device in the first cell. For example, since the utility function may be non-linear, the offset brought about by the second radio resources influences the computation of the share of the first radio resources in the first cell.

At least one or each of the utility function and the further utility function may be a monotonic function. At least one or each of the utility function and the further utility function may comprise at a logarithm. Alternatively or in addition, at least one or each of the utility function and the further utility function may comprise a step function comprising one or more steps. The one or more steps in the utility function for the respective radio device may define at least one of a minimum requirement as to the capacity or the bit rate and a maximum requirement as to the capacity or the bit rate for the respective radio device.

The method may further comprise or initiate a step of receiving, at the first RR, a report from the first RA, the report being indicative of a total potential of all radio resources allocated or allocatable in the first cell by the first RA for at least one or each of the radio device and the one or more further radio devices.

Radio resources allocated or allocatable in the first cell by the first RA may be (e.g., collectively) referred to as the total radio resources in the first cell or the total radio resources of the first RA or the channel capacity of the first cell or the channel capacity allocated by the first RA.

At least one of the first radio resources, the second radio resources, the third radio resources, the further first radio resources, the further second radio resources, and the allocated or allocatable radio resources may be indicated, computed or defined in terms of at least one of an amount of the respective radio resources, a quantity of the respective radio resources, a bandwidth of the respective radio resources, a (e.g., achievable or estimated) channel capacity of the respective radio resources, a (e.g., achievable or estimated) number of bits of the respective radio resources, and a (e.g., achievable or estimated) bit rate of the respective radio resources. The amount of the respective radio resources may be a number of physical resource blocks (PRBs).

For example, each of the first and second control information may be indicative of at least one of a capacity of the respective radio resource and a bit rate of the respective radio resource. The second and first control information may be indicative of first and second bit rates and/or first and second capacities of the first and second radio resources allocated by the first and second RAs, respectively, to the radio device.

The sum of the first radio resources and the second radio resources may be the sum of the capacity of the first radio resources and the capacity of the second radio resources. Alternatively or in addition, the sum of the first radio resources and the second radio resources may be the sum of the bit rate of the first radio resources and the bit rate of the second radio resources.

The bit rate may be an estimated, potential or expected bit rate. The bit rate of the respective radio resources may be estimated, e.g., based on a signal to noise ratio (or signal to interference and noise ratio) and/or a modulation and coding scheme.

The method may further comprise or initiate a step of receiving, at the first RR, a report from the first RA, the report being indicative of a radio quality of each of at least one of the first radio resources for the radio device in the first cell and the further first radio resources for the further radio device in the first cell.

Alternatively or in addition, the first control information may comprise a radio quality of each of at least one of the second radio resources for the radio device in the second cell and the further second radio resources for the further radio device in the second cell.

The report may be indicative of the quality (e.g., the channel efficiency) of the respective (e.g., first) radio resources allocated or allocatable to the respective one of the radio device or the one or more further radio devices.

The quality may be indicated in terms of a channel capacity per radio resources, a number of (e.g., achievable) bits per radio resources or a (e.g., achievable) bit rate per radio resources.

The method may further comprise or initiate a step of computing the potential of each of at least one of the first radio resources, the second radio resources, the further first radio resources, and the further second radio resources by multiplying an amount of the respective radio resources with the reported radio quality of the respective radio resources. Alternatively or in addition, the method may further comprise or initiate a step of computing a total potential of all radio resources allocated or allocatable in the first cell by the first RA for at least one or each of the radio device and the one or more further radio devices by multiplying an amount of the all radio resources with the radio quality reported for the respective radio device.

The total radio resources may be reported in terms of a number of bits or a bit rate, e.g., since the total radio resources relate to different radio devices. The potential of the first radio resources may be computed by multiplying the total potential for the radio device with the share. Alternatively or in addition, the potential of the respective further first radio resources may be computed by multiplying the total potential for the respective further radio device with the respective further share.

The allocation of the respective radio resources may comprise scheduling at least one of transmissions to the radio device and receptions from the radio device.

The allocation by the respective RA may comprise scheduling one or more transmissions (e.g., in the cell associated to the respective RA) to the radio device and/or scheduling one or more receptions (e.g., in the cell associated to the respective RA) from the radio device. Scheduling one or more transmissions may comprise transmitting, from the respective RA to the radio device, one or more scheduling assignments for the one or more transmissions to the radio device. Scheduling one or more receptions may comprise transmitting, from the

respective RA to the radio device, one or more scheduling grants for the one or more receptions from the radio device.

The method may further comprise or initiate a step of comparing a potential, particularly a capacity or a bit rate, of the second radio resources as indicated by the first control information with a potential, particularly a capacity or a bit rate, of the first radio resources. Alternatively or in addition, the method may further comprise or initiate a step of maintaining respective radio resources providing the greater potential, particular the greater capacity or bit rate, according to the comparison while the potential, particularly the capacity or the bit rate, of the respective radio resources is equal to or less than a maximum potential,

particularly a maximum capacity or a maximum bit rate. Alternatively or in addition, the method may further comprise or initiate a step of reducing the share of the respective radio resources providing the greater potential, particularly the greater capacity or bit rate, according to the comparison if the potential, particularly the capacity or the bit rate, of the respective radio resources is greater than the maximum potential, particularly the maximum capacity or the maximum bit rate. Alternatively or in addition, the method may further comprise or initiate a step of setting to zero the share of the respective radio resources providing the lesser potential, particular the lesser capacity or bit rate, according to the comparison.

The method, particularly the controlling step, may be implemented to fulfill a requirement as to a minimum rate (minimum rate requirement) and/or a requirement as to a maximum rate (maximum rate requirement) of the radio device. Conventional scheduling techniques such as those presented in the documents "Downlink Packet Scheduling in LTE Cellular Networks: Key Design Issues and a Survey" by F. Capozzi, G. Piro, L.A. Grieco, G. Boggia and P. Camarda, IEEE Communication Surveys & Tutorials, Vol. 15, No. 2, 2013; "Carrier load balancing and packet scheduling for multi-carrier systems", Yuanye Wang, Klaus I. Pedersen, Troels B. Sorensen and Preben E. Mogensen, IEEE Transactions on Wireless Communications, Vol. 9, No. 5, May 2010; and "Optimal traffic

aggregation in multi-RAT heterogeneous wireless networks" by Sarabjot Singh, Shu-pin Yeh, Nageen Himayat, and Shilpa Talwar, IEEE International Conference on Communications - Workshops 2016" cannot take a minimum rate requirement into account, e.g., because a hypothetical enhancement for minimum or maximum rate requirements would involving at least one of additional complexity or high signaling exchange demands.

In any aspect, the technique may be implemented as a distributed split- responsibility scheduler for multi-connectivity. The controlling step may control the allocation (e.g., the scheduling) under the conditions of the multi-connectivity, a fairness provision and/or the minimum rate requirement.

The RRs, the RAs and/or the base stations serving the respective cells may form, or may be part of, the RAN, e.g., according to the Third Generation Partnership Project (3GPP) or according to the standard family IEEE 802.11 (Wi-Fi). The method may be performed by one or more embodiments of the RRs, respectively, in the RAN (e.g., the first, second and/or third RR). The RAN may comprise one or more base stations, e.g., each serving a respective cell and implementing the associated respective RA.

Any of the radio devices may be a 3GPP user equipment (UE) or a Wi-Fi station (STA). The radio device may be a mobile or portable station, a device for machine- type communication (MTC), a device for narrowband Internet of Things (NB-loT) or a combination thereof. Examples for the UE and the mobile station include a mobile phone, a tablet computer and a self-driving vehicle. Examples for the portable station include a laptop computer and a television set. Examples for the MTC device or the NB-loT device include robots, sensors and/or actuators, e.g., in manufacturing, automotive communication and home automation. The MTC device or the NB-loT device may be implemented in a manufacturing plant, household appliances and consumer electronics.

The radio device may be wirelessly connected or connectable (e.g., according to a radio resource control, RRC, state or active mode) with those cells (i.e., with those base stations) involved in the multi-connectivity.

Any one of the base stations or cells may encompass a station that is configured to provide radio access to any one of the radio devices. The base stations or cells may also be referred to as transmission and reception point (TRP), radio access node or access point (AP). The base station, the RAN and/or at least one of the radio devices may function as a gateway (e.g., between the RAN and the Internet) and/or may provide a data link to a host computer providing data that is transmitted to the radio device using at least one of the multi-connectivity and the first and/or second radio resources allocated by the first and/or second RA, respectively. Examples for the base stations may include a 3G base station or Node B, 4G base station or eNodeB, a 5G base station or gNodeB, a Wi-Fi AP and a network controller (e.g., according to Bluetooth, ZigBee or Z-Wave).

The RAN may be implemented according to the Global System for Mobile

Communications (GSM), the Universal Mobile Telecommunications System

(UMTS), 3GPP Long Term Evolution (LTE) and/or 3GPP New Radio (NR).

Any aspect of the technique may be implemented on a Physical (PHY) layer, a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer and/or a Radio Resource Control (RRC) layer of a protocol stack for the radio

communication. For example, each RA may be implemented on the PHY layer and/or the MAC layer. Alternatively or in addition, each RR may be implemented on the RLC layer and/or the RRC layer.

As to another aspect, a computer program product is provided. The computer program product comprises program code portions for performing any one of the steps of the method aspect disclosed herein when the computer program product is executed by one or more computing devices. The computer program product may be stored on a computer-readable recording medium. The computer program product may also be provided for download, e.g., via the RAN, the Internet and/or the host computer. Alternatively, or in addition, the method may be encoded in a Field-Programmable Gate Array (FPGA) and/or an Application-Specific Integrated Circuit (ASIC), or the functionality may be provided for download by means of a hardware description language.

As to a device aspect, a device for controlling an allocation of radio resources in a radio access network (RAN) configured to provide multi-connectivity to a radio device through multiple cells is provided. The device comprises a controlling unit configured to control an allocation of radio resources in a radio access network (RAN). The RAN is configured to provide multi-connectivity to a radio device through multiple cells each associated with a resource allocator (RA) configured to allocate radio resources to the radio device in the respective cell. Each RA is associated with a resource regulator (RR) configured to control the allocation of the respective radio resources by the respective RA to the radio device according to a share of the respective radio resources in the respective cell. The device is configured to perform any one of the steps of the method aspect.

As to a further aspect, a communication system including a host computer is provided. The host computer comprises a processing circuitry configured to provide user data, e.g., transmitted to the radio device in the multi-connectivity and/or using the first and/or second radio resources allocated according to the first and/or second control information. The host computer may further comprise a communication interface configured to forward the user data to a cellular network (e.g., the RAN and/or the base station) for transmission to the radio device (e.g., a UE). A processing circuitry of the cellular network may be configured to execute any one of the steps of the method aspect.

The communication system may further include the radio device (e.g., the UE). Alternatively or in addition, the cellular network may further include one or more of the base stations (e.g., embodying the RAs) configured for radio communication with the radio device and/or to provide a data link between the radio device and the host computer using the method aspect. The processing circuitry of the host computer may be configured to execute a host application, thereby providing the user data and/or any host computer

functionality described herein. Alternatively, or in addition, the processing circuitry of the radio device may be configured to execute a client application associated with the host application.

Any one of the devices, the RRs, the RAs, the base stations, the radio devices (e.g., UEs), the communication system or any node or station for embodying the technique may further include any feature disclosed in the context of the method aspect, and vice versa. Particularly, any one of the units and modules disclosed herein may be configured to perform or initiate one or more of the steps of the method aspect.

Brief Description of the Drawings

Further details of embodiments of the technique are described with reference to the enclosed drawings, wherein:

Fig. 1 shows a schematic block diagram of an embodiment of a device for

controlling an allocation of radio resources in a RAN configured to provide multi-connectivity to a radio device through multiple cells;

Fig. 2 shows a flowchart for a method of controlling an allocation of radio

resources in a RAN configured to provide multi-connectivity to a radio device through multiple cells, which method may be implementable by the device of Fig. 1;

Fig. 3 schematically illustrates a first example of the RAN comprising at least one embodiment of the device of Fig. 1;

Fig. 4 schematically illustrates a second example of the RAN comprising at least one embodiment of the device of Fig. 1;

Fig. 5 schematically illustrates a third example of the RAN comprising at least one embodiment of the device of Fig. 1; Fig. 6 schematically illustrates a first implementation of computing a share of radio resources;

Fig. 7 shows a flowchart of an implementation of the method of Fig. 2;

Fig. 8 schematically illustrates a second implementation of computing a share of radio resources;

Fig. 9 schematically illustrates a fourth example of the RAN comprising at least one embodiment of the device of Fig. 1;

Fig. 10 shows a schematic block diagram of a resource regulator embodying the device of Fig. 1;

Fig. 11 schematically illustrates an example telecommunication network

connected via an intermediate network to a host computer;

Fig. 12 shows a generalized block diagram of a host computer communicating via a base station or radio device functioning as a gateway with a user equipment over a partially wireless connection; and

Figs. 13 and 14 show flowcharts for methods implemented in a communication system including a host computer, a base station or radio device functioning as a gateway and a user equipment.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as a specific network environment in order to provide a thorough understanding of the technique disclosed herein. It will be apparent to one skilled in the art that the technique may be practiced in other embodiments that depart from these specific details. Moreover, while the following embodiments are primarily described for a New Radio (NR) or 5G implementation according to 3GPP, it is readily apparent that the technique described herein may also be implemented for any other radio communication technique, including a Wireless Local Area Network (WLAN) implementation according to the standard family IEEE 802.11 and 3GPP LTE (e.g., LTE-Advanced or a related radio access technique such as MulteFire).

Moreover, those skilled in the art will appreciate that the functions, steps, units and modules explained herein may be implemented using software functioning in conjunction with a programmed microprocessor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Digital Signal Processor (DSP) or a general purpose computer, e.g., including an Advanced RISC Machine (ARM). It will also be appreciated that, while the following embodiments are primarily described in context with methods and devices, the invention may also be embodied in a computer program product as well as in a system comprising at least one computer processor and memory coupled to the at least one processor, wherein the memory is encoded with one or more programs that may perform the functions and steps or implement the units and modules disclosed herein.

Fig. 1 schematically illustrates a block diagram of an embodiment of a device for controlling an allocation of radio resources in a radio access network (RAN) configured to provide multi-connectivity to a radio device. The device is generically referred to by reference sign 100.

The multi-connectivity is provided to the radio device through multiple cells each associated with a resource allocator (RA) configured to allocate radio resources to the radio device in the respective cell. Each RA is associated with a resource regulator (RR) configured to control the allocation of the respective radio resources by the respective RA to the radio device according to a share of the respective radio resources in the respective cell.

The device 100 comprises a resource information receiving module 102 that receives, at a first RR associated with a first RA associated with a first cell of the multi-connectivity, a first control information from a second RR associated with a second RA associated with a second cell of the multi-connectivity. The first control information is indicative of second radio resources allocated to the radio device in the second cell. The device 100 further comprises a resource allocation controlling module 104 that controls the allocation of first radio resources to the radio device in the first cell by computing the share of the first radio resources in the first cell depending on the second radio resources. The device 100 further comprises a resource information sending module 106 that sends, from the first RR, a second control information to the second RR. The second control information is indicative of the first radio resources resulting from the computed share.

Any of the modules of the device 100 may be implemented by units configured to provide the corresponding functionality.

The device 100 may also be referred to as, or may be embodied by, the first RR. The first RR 100 and the associated first RA may be in direct communication or embodied by the same node of the RAN, e.g., a base station.

Fig. 2 shows an example flowchart for a method 200 of controlling an allocation of radio resources in a radio access network (RAN) configured to provide multi connectivity to a radio device. The multi-connectivity is provided to the radio device through multiple cells each associated with a RA configured to allocate radio resources to the radio device in the respective cell. Each RA is associated with a RR configured to control the allocation of the respective radio resources by the respective RA to the radio device according to a share of the respective radio resources in the respective cell.

In a step 202, a first control information is received at a first RR associated with a first RA associated with a first cell of the multi-connectivity from a second RR associated with a second RA associated with a second cell of the multi

connectivity. The first control information is indicative of second radio resources allocated to the radio device in the second cell. In a step 204, the allocation of first radio resources to the radio device in the first cell is controlled by computing the share of the first radio resources in the first cell depending on the second radio resources. In a step 206, a second control information is sent from the first RR to the second RR. The second control information is indicative of the first radio resources resulting from the computed share.

The method 200 may be performed by the device 100, e.g., the first RR. For example, the modules 102, 104 and 106 may perform the steps 202, 204 and 206, respectively.

The allocated radio resources may be applied to uplink (UL), downlink (DL) or direct communications between radio devices, e.g., device-to-device (D2D) communications or sidelink (SL) communications. Herein, any radio device may be a mobile or portable station and/or any radio device wirelessly connectable to a base station of the RAN 300, or to another radio device. For example, the radio device may be a user equipment (UE), a device for machine-type communication (MTC) or a device for (e.g., narrowband) Internet of Things (loT). Two or more radio devices may be configured to wirelessly connect to each other, e.g., in an ad hoc radio network or via a 3GPP SL connection.

Furthermore, any base station may be a station providing radio access, may be part of a radio access network (RAN) and/or may be a node connected to the RAN for controlling the radio access. For example, the base station may be an access point, for example a Wi-Fi access point.

Any pair of a RR and a RA connected to the RR may jointly implement a scheduler for allocating the radio resources, e.g., a medium access control (MAC) scheduler. The technique may be implemented by splitting and/or modifying the functionality of an existing scheduler (e.g., including a MAC scheduler) into a first part referred to as the RR and a second part referred to as the RA. The combination of RR and RA may also be referred to as a split-responsibility scheduler.

In the presence of multi-connectivity, each RR may control one RA for one cell, while there is one RA for each cell. In the absence of multi-connectivity, one RR may handle several cells and/or multiple access technologies (RATs), while there is one RA for each cell.

Fig. 3 shows an example of a configuration of the RAN 300, in which each of the RRs 100-1, 100-2 and 100-3 handles only one cell 306-1, 306-2 and 306-3, respectively, i.e., controls only one RA 304-1, 304-2 and 304-3, respectively.

As notation used herein for reference signs of the format XYZ-j, for any integer j, a j-th association 303-j may comprise a control link between the respective RR 100-j and the respective RA 304-j. Alternatively or in addition, a j-th association 305-j between the respective RA 304-j and the respective cell 306-j may comprise a control link to the base station providing radio access in the respective cell 306-j. While three associations (j = 1, 2 and 3) are illustrated in Fig. 3, the RAN 300 may comprise 2, 4 or more associations. All or a subset of the associations may define the legs of the multi-connectivity of the radio device. The technique may be implemented based on a split-responsibility scheduler by building a distributed scheduler with communication links 301 between RRs 100-j controlling different RAs 304-j, e.g., as shown in each of the Figs. 2 to 5 and 9.

The first control information 310-1 may be received from the second RR 100-2 upon request. The first RR 100-1 may send the request to the second RR 100-2.

In the exemplary state of the RAN illustrated in Fig. 3, no radio device is currently in multi-connectivity (particularly dual connectivity) with the RAN. Flence, the first control information 310-1 received at the first RR 100-1 from the second RR 100-2 in the step 202 may comprise no entry for the radio device. Alternatively or in addition, the first control information 310-1 may be indicative of the second radio resources 312-2 for the radio device as none, zero or no second radio resources 312-2.

The second control information 310-2 transmitted in the step 206 from the second RR 100-1 to the second RR 100-2 may be indicative of the first radio resources of the radio device served by the first cell 306-1. Alternatively or in addition, upon request from the second RR 100-2 as to a further radio device in single

connectivity with the second cell 306-2, the second control information 310-2 may comprise no entry for the further radio device or the second control information 310-2 may be indicative of the further first radio resources 312-1 as none, zero or no further first radio resources 312-1.

While Fig. 3 schematically illustrates an exemplary RAN 300 in which each RR 100-j handles only one cell 306-j by controlling the allocation performed by only one RA 304-j, Fig. 4 schematically illustrates an exemplary RAN 300 in which at least one or each physical RR (i.e., an RR unit) handles multiple cells 306-j (e.g., for j= 1 to 3) by controlling multiple RAs 304-j respectively associated to one of the multiple cells 306-j. Optionally, the multiple cells 306-j provide radio access to the radio device according to different access technologies (RATs),

respectively.

Fig. 4 shows a variant of the configuration of the RAN 300 of Fig. 3, in which a physical RR comprises multiple virtual RRs 100-j each controlling a respective one of multiple RAs 304-j. The first control information and the second control information is exchanged between the virtual RRs 100-1 and 100-2. In any embodiment, functionalities provided or performed by any one of the RR 100-j may comprise at least one of the following RR functions. A first RR function comprises handling (e.g., as part of the controlling according to the step 204) a long-term fairness, e.g., considering QoS requirements of the respective radio device. A second RR function comprises computing or calculating (e.g., as part of the controlling according to the step 204) one or more shares, e.g., the share of the first radio resources or any further share for the respective further radio devices. The share may comprise a relative resource share. The share may be computed per radio device (e.g., per UE), per radio bearer of the respective radio device and/or per Internet Protocol (IP) flow of the respective radio device. A third RR function signals the computed share (or an indicator of the corresponding radio resources) to the respective RA, which will use the signaled share when it performs a resource allocation decision (e.g., scheduling).

Alternatively or in addition, in any embodiment, functionalities provided or performed by any one of the RA 304-j may comprise at least one of the following RA functions. A first RA function comprises handling (e.g., allocating, particular scheduling) all or at least some short-term aspects and/or protocol aspects of a MAC scheduler. For example, the RA 304-j focuses on optimizing transmissions over the radio by handling objectives or performing features of the PHY layer (also: Layer 1 or LI) and/or the MAC layer (also: Layer 2 or L2) such as performing retransmission, processing channel state information (CSI) and/or performing link adaptation. A second RA function comprises reporting, to the associated RR, a cost for radio resources or a value for radio resources, e.g., in terms of bits per radio resources or an equivalent quantity. The cost may be reported for each radio device allocated by the respective RA (e.g., per UE, per radio bearer or per IP flow). A third RA function comprises receiving the share (e.g., the relative resource share) for the respective radio device (e.g., per UE, per bearer or per flow) and using the received share as an input to the allocation of the radio resources to the respective radio device (e.g., for allocating the first radio resources to the radio device). The allocation may comprise a local scheduling performed by the respective RA (e.g., the first RA). Any local scheduling may be performed as the allocation. The allocation may uphold the received one or more shares (e.g., the relative resource shares) with a specified time resolution. In the case of multi-connectivity, the RRs 100-j and the RAs 304-j function as a distributed scheduler. The RRs 100-j calculate resource shares for the legs that they control and exchange control information with each other according to the steps 202 and 206, e.g., in an iterative process to control the allocation according to the step 204. Controlling the allocation according to the step 204 based on the received first control information can maximize a total utility of all connections (e.g., a total utility being the sum of the utility of each of the radio devices) Controlling the allocation according to the step 204 may comprise scheduling the radio resources well and efficiently.

Fig. 5 schematically illustrates an exemplary RAN 300 comprising radio devices 308-jk in dual connectivity (DC) with the cells j and k. In the example illustrated in Fig. 5, three mutually overlapping cells 306-j with j=l to 3 are illustrate, so that DC is possible for the radio device 308-12 in DC with the first cell 306-1 and the second cell 306-2, a further radio device 308-13 in DC with the first cell 306-1 and a third cell 306-3, and another radio device 308-23 in DC with the second cell 306-2 and the third cell 306-3.

Fig. 5 schematically illustrates a configuration of the split-responsibility scheduler comprising the RRs 100-j and the RAs 304-j. While the scenario shown in Fig. 5 comprises three UEs 308-12, UEs 308-13 and UEs 308-23 each in DL, the technique is applicable to any multi-connectivity. In this configuration, there is a communication according to the steps 202 and 206 between the RRs 100-j to exchange control information related to the UEs in multi-connectivity. The control information received by the respective RR 100-j (e.g., the first control information received by the first RR 100-1) is used to compute according to the step 204 the one or more shares (e.g., the most suitable relative resource shares) that each UE (e.g., in the associated cell 306-j) should receive on the respective RA 304-j.

For clarity and conciseness, and not as a necessary limitation, the technique is described herein below as an embodiment of the first RR 100-1. In any

embodiment of the RAN 300, any one of the other RRs may, alternatively or additionally, embody the technique. Furthermore, also for clarity and

conciseness and not as a necessary limitation, radio devices are referred to as UEs. Moreover, the effect of controlling the allocation, which can be brought about by embodiments of technique, is described for the UE 308-12 as a non limiting example.

On a high level, the method 200 may be implemented as an iterative process or algorithm involving the three steps 202, 204 and 206. In the step 202, the first RR 100-1 gets input (e.g., the first control information 310-1) from other RRs 100-j for j¹ 1 (e.g., from the second RR 100-2) regarding additional radio resources (e.g., the second radio resources 312-2) that one or more UEs (e.g., the UE 308- 12) also handled by the other RRs (e.g., the second RR 100-2) will get on other legs of the multi-connectivity (i.e., on legs other than a first leg controlled by the first RR 100-1).

The first control information may comprise an amount of the respective radio resources for the respective radio device (e.g., an amount of the second radio resources), a potential provided by the respective radio resources for the respective radio device (e.g., by the second radio resources) and/or a utility provided by the respective radio resources for the respective radio device (e.g., by the second radio resources). The potential provided by the respective radio resources may comprise a number of bits or a bit rate provided by the respective radio resources or a capacity provided by the respective radio resources.

In the case of multi-connectivity involving the third cell 306-3, the first control information may further be indicative of third radio resources allocated by the third RA 304-3 to the UE. Hereinbelow, the indication of the second radio resources (and optionally third radio resources) in the second control

information is (e.g., collectively) described as an additional bit rate for conciseness and not limitation. The indication of the second radio resources in the second control information may be according to the last iteration of the algorithm.

According to the step 204, the share (also referred to as a resource share) for the controlled legs is computed (i.e., calculate) taking the additional bit rate into account.

In the step 204, the resulting bit rates that one or more UEs in multi-connectivity (including at least the UE 308-12) get in the first cell (i.e., due to the allocation controlled by the first RR 100-1 and performed by the RA 304-1) are signaled to one or more other RRs (including at least the second RR 100-2) that also handle the respective UE.

The resulting bit rates are used as input for a next iteration of the algorithm at the respective other RR 100-j (e.g., j=2). Since the other RRs 100-j (e.g., j=2) may also perform the method 200, the second control information signaled from the other RR to the first RR 100-1 may serve as the first control information in an iteration of the method 200 performed by the first RR 100-1.

Below embodiments provide exemplary implementations of the step 202, 204 and 206 further broken down into smaller parts. Moreover, the step 202, 204 and 206 are repeated.

Since the responsibility for the scheduling may be split between to the RRs 100-j and the RAs 304-j on many different scales (e.g., in terms of the RR functions, the RA functions and/or a number of cells 308 of the RAN 300), there are many possible means to perform the information exchange according to the step 202 and 206. The distributed scheduler according to the RRs 100-j and the RAs 304-j may be used (e.g., internally or in a virtualization) in a parallelized

implementation of a multi-cell scheduler. In this case, the communication may take place on internal buses, e.g., as indicated for the control information 310-1 and 310-2 in Fig. 4. In other words, the second example of the RAN illustrated in Fig. 4 may be implemented as a variant of the third example of the RAN illustrated in Fig. 5.

In any embodiment, a protocol and/or an interface may be specified for the communication links 301 and/or the control information exchange according to the step 202 and 206. For example, the technique may be incorporated in any existing protocol. The Xn application protocol (XnAP) for 3GPP NR or the corresponding X2AP for 3GPP LTE may be used, e.g., since that is the protocol that handles DC-related signaling between gNBs and ng-eNBs (in the case of 3GPP NR) or between eNBs (in the case of 3GPP LTE).

Optionally, in any embodiment, one of the tasks (i.e., one of the RA functions) of the first RA 304-1 is to report at least one of a potential and a quality of the first radio resources 312-1 in the first cell 306-1 for the UE 308-12 or at least one of the respective potential and the respective quality of the respective radio resources for each of the UE 308-12 and the one or more further UEs 308-13 allocated by the first RA 304-2 (i.e., served by at least the first cell 306-1). The potential may be defined, indicated, reported or computed in terms of a channel capacity, a number of bits and/or a bit rate of the radio resources. The quality may be may be defined, indicated, reported or computed in terms of a channel efficiency, a number of (e.g., achievable) bits per radio resources and/or a (e.g., achievable) bit rate per radio resources. The potential may be reported (e.g., indicated in the report) as the number of bits per radio resources, the bit rate per radio resources or an equivalent quantity.

The potential and/or the quality may be indicated for each of the UE 308-12 and the one or more further UEs 308-13 served by at least the first cell 306-1. The potential and/or the quality may be computed by the first RA 304-1 and signaled to the first RR 100-1 according to the split-responsibility scheduler. Optionally, the potential and/or the quality is computed and/or reported per radio bearer or per IP flow.

Alternatively or in addition, one of the tasks (i.e., one of the RA functions) of the first RA 304-1 (or each RA 304-j) is to report a total potential of each of the radio devices allocated by the first RA 304-1 and/or to report the potential of each the respective radio resources (e.g., of the first radio resources) allocated to the respective UE (e.g., the UE 308-12). The potential may be a (e.g., achievable) capacity, a (e.g., achievable) number of bits or a (e.g., achievable) bit rate of the respective radio resources. For example, a total potential of the respective UE (e.g., the UE 308-12) achievable if all radio resources available in the first cell may be reported. The potential of the respective radio device may be computed by multiplying the total potential for the respective radio device with the share of the respective radio device in the first cell.

In a variant, the report may be indicative of the quality of the first radio resources 312-1. The first RR 100-1 may compute the corresponding potential (e.g., the corresponding number of bits or the corresponding bit rate) using the reported and/or estimated quality. For example, an amount of the first radio resources 312-1 is multiplied with the reported quality, resulting in the potential. The amount may be derived from a total amount of radio resources allocated or allocatable by the first RA 304-1 in the first cell 306-1 and the share for the radio device 308-12. For example, the total amount of the radio resources may be multiplied with the share, resulting in the radio resources for the radio device 308-12.

At least one of the first RR 100-1 and the first RA 304-1 may compute (e.g., estimate) the (e.g., first or total) potential of the respective (e.g., first or all, respectively) radio resources allocated or allocatable by the first RA 304-1 for each radio device that is allocated by the first RA 304-1. The potential may comprise the number of bits or the bit rate achievable by the respective (e.g., first or all) radio resources. The potential for the respective radio device may be computed (e.g., estimated) using the quality for the respective radio device. The quality may be derived from channel state information (CSI), a signal to noise ratio (SNR) and/or a signal to interference and noise ratio (SINR), e.g., reported by the respective radio device.

The potential and/or the quality may be computed and signaled using different types of information. By way of example, the RA 304-1 computes and reports to the RR 100-1 a total potential for the first UE 308-12, e.g., the capacity, the number of bits or the bit rate achievable if all radio resources (i.e., the total amount of radio resource) allocated or allocatable by the first RA 304-1 in the first cell 306-1 were allocated to the first UE 308-12. The total potential may be implemented as a total potential number of bits or a total potential bit rate of the UE 308-12, i.e., the number of bits or the bit rate the UE 308-12 would achieve or is estimated to achieve, if all (i.e., 100%) of the radio resources of the first cell 306-1 were allocated to the UE 308-12.

The total potential (e.g., the total number of bits, the total potential bit rate or the total channel capacity) is represented by a_i i.e. the total potential for the UE i (e.g., the UE 308-12) through the cell l (e.g., the first cell 306-1), which may also be referred to as link l or leg l (e.g., because one RA handles only one cell). While the quality (e.g., a number of bits, a bit rate or a channel capacity per radio resources) of the first radio resources allocated to the UE i may be an intrinsic measure per radio resources for the link l between the cell l and the UE i (e.g., the UE 308-12), the respective potential (e.g., the total potential) may be an extensive measure for the link , which is proportional to the amount of the respective radio resources (e.g., of all radio resources of the cell l). For example, the total potential for the link l, a_l is a bit rate that the UE i (e.g., the first UE 308-12 in DC through the links 1=1 and 1=2) would get on link Z, if 100% of the radio resources of the cell l were allocated to the UE i (e.g., the first UE 308-12) by the RA l (e.g., the first RA 304-1).

The value ¾ is the computed or current value of the share assigned to the UE i on the link Z. The index l may correspond to any one of the indices j or k described above. Without loss of generality, the UE i may be the first UE 308-12 and the link l may correspond to the first cell 306-1. Then, the combined potential for the UE i (or aggregated potential, e.g., the combined bit rate the UE i would transmit at) is given by

which represents the summation of the potentials (e.g., the bit rates) the UE i would achieve on all its links l (i.e., connections or legs) to different cells of the multi-connectivity (e.g., DC).

The bit rate of the UE i on the link l is given by

The total available resource share of a given cell (i.e., a given link or associated RA) is 100%. The step 204 may comprise computing the share by dividing the total available share into step shares, which are represented by d. In the case of equally sized step shares, each step share may be equal to , where K is the

number of step shares. For example, d = 0.5% for K = 200. The size of the step share may be adjusted depending on a number of UEs (or users) connected to the respective links l, e.g., the first cell 306-1.

Increasing and decreasing the share by one step share is associated with incremental and decremental radio resources that correspond to incremental and decremental capacity of the radio resource, and/or incremental and decremental bit rates achievable by the radio resources.

For example, the value

is the total bit rate the UE i would get considering the current values of share. The value

is the incremental bit rate of the UE i on link l, which represents the bit rate the UE i would get if one additional step share was given to the UE i on the link Z. On the other hand,

is the decremental bit rate of the UE i on the link l, which represents the bit rate the UE i would get if one step share was removed from the current value of the share assigned to the UE i on the link 1. The term

represents the bit rates the UE i did get or would get on the other cells, k ¹ l, of its multi-connectivity, which is the information exchanged between RRs according to the steps 202 and 206.

In any embodiment, e.g., as symbolically outlined above, the additional bit rate (or additional capacity) provided by the respective radio resources in another cell may be received in the step 202 and used in the step 204 for computing the utility in the present cell. Alternatively or in combination, in any embodiment, the additional utility may be exchanged and converted to the additional bit rate (or the additional capacity), e.g., since the utility function is invertible.

Based on the incremental and decremental bit rates, a utility decrement and a utility increment may be computed, respectively, according to the step 204. The utility increment U_inc is the incremental value of the utility function that would be provided to the system in case one additional step share was given to a certain UE (e.g., the UE 308-12), thus it is a relationship between at least x_cur and x_inc. On the other hand, the utility decrement U_dec is the decremental value of the utility function that would be deducted from the system in case one step share was removed from a certain UE (e.g., the UE 308-12), thus it is a

relationship between at least x_cur and x_dec. Based on the utility increment and utility decrement determined for each of the UEs allocated by the first RA 304-1 together with the incremental and

decremental bit rates determined for each of the UEs (e.g., the UE 308-12 and 308-13) allocated by the first RA 304-1, the share of each for each of the UEs allocated by the first RA 304-1 may be computed so as to (e.g., iteratively) increase or maximize the utility function.

Two example functions for the utility increment (i.e., the increment of the utility function) and the utility decrement (i.e., decrement of the utility function) are given below. However, any other utility functions modeling the utility decrement and utility increment are supported by the method 200.

The first example can provide a global proportional fairness among all the UEs in each cell 306, and by virtue of the control information exchanged in the steps 202 and 206, in the RAN 300. To achieve such goal, the functions for the utility increment and the utility decrement are based on the (e.g., natural) logarithm function log(·) and are given by the following expressions:

Using these functions for U_inc and U_dec, it may or may not be guaranteed that the UEs will achieve a requirement as to a minimum and/or maximum bit rate. However, it may be guaranteed that proportional fairness is achieved.

Particularly, simulations of an embodiment of the method 200 using the log- based U_inc and U_dec have verified a near-optimal performance.

In other words, the utility function may be

A second example for the functions for the utility increment, U_inc, and the utility decrement, U_dec, may be used to achieve or guarantee a requirement as to a minimum bit rate, x_min, and/or a maximum bit rate, x_max, for all UEs (e.g., all allocated by the first RA 304-1) the respective UEs (e.g., for the UE 308-12). The U_inc and U_dec functions are:

wherein the factor a is a value controlling an incentive for increasing the utility in the system. The factor b is a weight for a minimum rate requirement, which may be used to prioritize UEs depending, for instance, on the mobile plan they subscribe to. A higher value of b means that there is a higher change of receiving a higher amount of share. The factor g works similarly to the factor b for a maximum rate requirement (instead of the minimum rate requirement controlled by the factor b).

Using the increment of the utility function and the decrement of the utility function, the step 204 may compute the share (i.e., the relative share) for at least one (e.g., the UE 308-12) or each of the UEs allocated by the first RA 304-1. For example, the method is performed by the RA 100-j, wherein the step 204 computes the share for each of the UEs allocated by the RA 304-j, i.e., the shares that the UEs should receive on the respective link j. The computed shares are signaled from the RR 100-j to the RA 304-j, which performs the allocation according to the computed shares.

Fig. 6 shows a flowchart for an exemplary implementation of the step 204 of the method 200. A first substep 602 of the step 204 comprises computing the values of utility increments and utility decrements for each UE. The highest value of utility increment and the lowest value of utility decrement are determined or selected. If the largest utility increment is higher than the lowest utility

decrement, one step share is moved or shifted from a donator (i.e., a UE or user providing the lowest utility decrement) to a receiver (i.e., a UE providing the largest utility increment) in a second substep 604.

The values of the utility increment and the utility decrement are re-computed for the donator UE and the receiver UE, which may be implemented as a repetition 602' of the substep 602. The substep 602 of determining the highest value of the utility increment and the lowest value of the utility decrement is also repeated. At the end of the substep 602 (or any of its repetitions 602') or at the beginning of the substep 604, if the largest utility increment is not higher than the lowest utility increment, the step 204 may be terminated, and the method 200 may be repeated.

Fig. 7 schematically illustrates a decentralized implementation of the method 200. The implementation of the method 200 may optionally comprise any of the features and steps described for the implementation of the step 204 with reference to Fig. 6 above.

More specifically, the implementation of the method 200 comprises an

initialization stage 710, a resource information receiving stage 720, a resource allocation controlling stage that implements the step 204, and resource information transmitting stage that implements the step 206. More specifically, the resource information receiving stage 720 comprises a substep that

implements the step 202 of receiving the first control information. The resource allocation controlling stage comprises a main computation 204-1 and an optional share refinement computation 204-2.

The substeps 731 to 736 in the main computation 204-1 and the substeps 741 to 743 in the optional share refinement computation 204-2 implement the step 204 of computing the share of the first radio resources allocated by the first RA 304-1 to the UE 308-12 and/or of each further first radio resources allocated by the first RA 304-1 to one or more further UEs. The step 206 comprises sending the second control information to one or more other RRs that are also involved in controlling the allocation of the UE 308-12 for the multi-connectivity. The potentials (e.g., the capacity and/or the bit rates) of the first radio resources and/or of each further first radio resources result from the computation 204 of the respective shares, e.g., in combination with the total potential of the respective radio device (e.g., the first the UE 308-12 and/or any one of the one or more further UEs 308-13). The potentials (e.g., the capacity and/or the bit rates) of the respective radio resources are sent in the second control information.

The second control information is used as input for a next iteration or repetition of the method 200. That is, the steps 202 and 206 may relate to the same information exchange step or to a single information exchange step. The implementation of the method 200 may be executed at the first RR 100-1 or each RR 100-j. The substep 711 comprises assigning equal shares to the UEs connected in the first cell 306-1, i.e., the UEs allocated by the first RA 304-2 associated with the first RR 100-1. The substep 711 is executed only once when the RA 304-1 did not have any connected UEs and/or when one or more UEs arrive in the first cell (e.g., responsive to a random access procedure with the arriving UE). In case there is already some UEs connected, this procedure is not executed anymore. This is the reason why it is under part of the initialization stage 710.

The substep 721 comprises receiving, from the RA 304-1, the potential capacity or potential bit rates for the UE 308-12 and/or each of the one or more further UEs allocated by the first RA 304-1.

The step 202 comprises receiving, in the first control information, a current value of the capacity or the bit rate for those UEs that are also allocated by the other RA 304-j, j¹l, for the multi-connectivity of the UE 308-12. The first control information is indicative of the capacity or the bit rate the UE 308-12 gets or would get from the other RAs 304-j, j¹l (i.e., on other links or legs and in other cells 306-j).

The UE-individual capacity or bit rate indicated in the first control information from the other RAs are summed up, which comprises the term used in

xinc, ^xdec, and ^x _Cur · This may be the only type of control information that is needed to be exchanged in a preferred implementation of the method 200. In other implementations, other types of information (e.g., a total potential bit rate, relative shares, and/or QoS requirements) may be exchanged depending on the functions for the utility increment U_inc and the utility decrement U_dec.

The substep 721 and the step 202 comprise acquiring or receiving the control information needed for the computation of the shares of the respective radio resources for the respective UEs allocated by the first RA 304-1 according to the step 204.

The main computation 204-1 comprises at least one of the substep 731 to 735 of the implementation of the method 200, e.g., in combination or accordance with the implementation of the step 204 describe above with reference to Fig. 6. The substep 736 checks whether there are UEs with assigned share smaller than the step share, which might happen in an initial executions of the method 200. If there is no UEs with assigned share smaller than the step share, step 206 is executed. The step 206 comprises sending, to the one or more other RRs, the second control information indicative of a current value of the capacity or the bit rate the UEs in multi-connectivity get or would get on the one or more links controlled by the RR 100-1, i.e., according to the allocation performed by the first RA 304-1 under the control of the RR 100-1.

The second control information may be received by the other RRs 100-j, j¹1, in the step 202 of the method 200 performed by each of the other RRs 100-j, j¹j 1,

If there are UEs 308- lj with assigned share smaller than the step share, the RR 100-1 executes the share refinement computation 204-2, which may comprise three substeps. In a substep 741, the UEs with shares smaller than the step share are determined and all those values of the respective share are summed up. A substep 742 assigns the value zero to the respective share for those UEs which had assigned a share smaller than the step share. The substep 743 equally splits the summed-up value of the share summed up in substep 741 among those UEs allocated by the first RA 304-1 with an assigned share higher than the step share. This procedure mainly reduces the time UEs would stay in multi-connectivity but only receiving a very small amount of data on that link with a very small share (e.g., a share of the first RA 304-1 that is insignificant relative to the total potential for the respective UE 308- 1j).

Fig. 8 shows a flowchart for a procedure of fulfilling a requirement per radio device (e.g., per UE) as to a minimum and/or a maximum of the capacity or bit rate. Fulfilling the requirement may be implemented in the step 204, e.g., after performing the computation of the share or one or more further shares according to any implementation of the step 204.

The procedure is executed locally, e.g., by the respective RR 100-j performing the method 200. Preferably, the procedure does not rely on any extra exchange of control information between the RRs of the RAN 300. For example, the

procedure may be performed based on the first control information received in the step 202. For each UE, a requirement as to a maximum bit rate may be determined or acquired in a substep 802 of the step 204. A bit rate provided by the respective radio resources in each of the cells may be estimated for each of the UEs in a substep 804. A loop 806 may be repeated for each UE having a maximum requirement as to the bit rate.

The procedure of fulfilling the requirement of the respective UE may comprise a step 808 of determining (e.g., checking) in which cell (or in which cells) of the RAN (e.g., in which cells currently used or not yet used for the multi-connectivity of the respective UE or on which connections from possibly multiple connections) the respective UE is estimated to have or is expecting to have a higher potential (e.g., a higher bit rate). Herein, the bit rate may be a data rate. The potential (e.g., the bit rate) may be higher on another cell compared to a currently used cell (e.g., the first cell 306-1), e.g., because of a high relative share and/or due to a high channel quality.

The procedure of fulfilling the requirement may further comprise a step 810 of keeping or maintaining the one or more (e.g., relative) shares in the one or more cells (or on the one or more connections) providing the higher or highest bit rate, e.g., until (i.e., up to a point at which) the estimated or expected bit rate is equal to the maximum rate requirement.

The processing of one or more shares of radio resources in one or more cells that provide less potential (e.g., less bit rates) compared to cell providing the higher or highest potential (e.g., the higher or highest bit rates) depends on whether a requirement for a maximum potential (e.g., a maximum bit rate) is already fulfilled by the radio resources in the cell providing the higher or highest potential (e.g., the higher or highest bit rates). Optionally, the procedure of fulfilling the requirement may further comprise a step of reducing the (e.g., relative) share to meet requirement for the maximum potential (e.g., the maximum bit rate), if the previously computed (e.g., relative) share is not fully needed to fulfill the maximum bit rate requirement. The latter step may comprise a substep 814 of computing the share needed to reach the maximum bit rate (e.g., the maximum bit rate), and a substep 816 of setting (i.e., assigning) the computed share. Alternatively or in addition, the (e.g., relative) share on the one or more cells or connections providing the lower or lowest potential (e.g., the lower or lowest bit rate) are set to zero in a substep 818, e.g., to reduce the time the UE stays in multi-connectivity, and/or if the maximum potential (e.g., the maximum bit rate) is not fulfilled (i.e., if the maximum bit rate is exceeded).

In an exemplary implementation of the procedure of fulfilling the requirement, if there is no requirement for a maximum potential for any of the UEs, the term multiplied by g in the second example of the functions for the utility increment U_inc and the utility decrement U_dec may be removed from the functions. For example, the factor g may be set to zero.

If at least one of the UEs has a requirement for a maximum potential, said term may be included in the functions U_inc and U_dec. Alternatively or in addition, the procedure of fulfilling the requirement (e.g., as illustrated in Fig. 8) may be performed.

An implementation of the procedure of fulfilling the requirement may cause at least one of the following advantages. As a first advantage, the main

computation of the method 200 may guarantee that, when a given UE has enough share to achieve its maximum rate requirement, controlling the allocation according to the step 204 can stop further increasing the one or more shares for the given UE (i.e., the method 200 can stop the given UE from receiving further step shares). Alternatively or in addition, the implementation of the step 204 may reduce the assigned share to be equivalent to the maximum bit rate requirement. As a second advantage, when reducing the assigned share to meet exactly the maximum bit rate requirement, the number of active

connections of UEs in multi-connectivity can be reduced.

In any embodiment or implementation, the values of assigned share computed by the RR 100-1 in the step 204 are indicated to the RA 304-1 associated with the RR 100-1 at a predefined or configured periodicity. The periodicity may be referred to as the time step of the method 200. For example, even though the distributed method 200 may be performed (e.g., continuously and/or in the background) by the respective RR (e.g., embodied by the respective base station also embodying the RA associated with the RR), the values of the one or more shares computed in the step 204 may be signaled to the associated RA only with the periodicity, e.g., every 100 ms. If within the periodicity (i.e., within a time interval between the periodic signaling of the one or more computed shares) one or more further UEs arrive in the associated cell and/or one or more UEs are disconnected from the associated cell, the RR may run the method and immediately inform the RA about the one or more shares most recently computed in the step 204. For an additional UE (e.g., responsive to the arrival of the additional UE), the method 200 may be

performed, e.g., as described with reference to the implementation of Fig. 7. When a given UE is or is to be disconnected, if the given UE had an assigned share (i.e., the respective share is greater than zero), the share or the

corresponding resources allocated by the first RA 304-1 may be equally split among the remaining UEs allocated by the first RA 304-1 (i.e., those UEs with assigned share greater than zero). This provides a means to always keep the sum of the shares assigned to the connected UEs equal to 100%.

In any RAN comprising at least one RR that handles (i.e., is associated with and/or controls the allocation performed by) more than one RA, the method 200 may be executed in the following way. All the RAs handled by a given RR may report the total potential of the UEs allocated by the respective RAs. The RR performs independent implementations or instances of the method 200, e.g., each according to the implementation of Fig. 7, for each of the RAs associated with the RR. By way of example, one virtual RR may be implemented for each of the associated RAs.

When multiple virtual RRs are embodied by one physical RR (e.g., by one base station), the control information exchanged in the steps 202 and 206 (e.g., being indicative of the bit rates of multi-connectivity UEs) are instantaneously received by the different virtual RRs siting inside the physical RR, e.g., by accessing shared- memory. Preferably, no modification is needed in implementing the method 200 to support such a partially centralized deployment. By means of the partially centralized deployment, possible delays or latency in exchanging the control information between the RRs of the RAN can be reduced or avoided.

Features and advantages of the virtual RRs may also apply to an exemplary deployment of the technique, which may implement multiple embodiments of the RRs 100-j and/or multiple instances of the method 200 in a cloud-based architecture. For example, all the virtual RRs 100-j of the RAN may be embodied by a cloud entity. The RRs 100-j for a huge number of nodes j (e.g., base stations or cells 306-j) may be execute in a cloud environment. In this case, an inter-RR protocol may be used, e.g., as indicated for the control information 310-1 and 310-2 in Fig. 9.

In a cloud implementation, all the functionalities related to the RRs 100-j may be implemented in one or few the cloud entities. The cloud entity may be

responsible for performing the tasks related to the RR. Each cloud entity may provide the functionality of a physical RR comprising multiple virtual RRs. For example, the cloud entity may handle more than one RA associated with one of the virtual RRs. The cloud entity may be responsible for handling all the RAs of the RAN.

Each of the associated RAs may report to the cloud entity the potential of the radio resources for each of the UEs and/or the total potential for each of the UEs, optionally further per radio bearer or IP flow. The cloud entity may perform independent instances of the method 200 (e.g., each according to the

implementation of Fig. 7) that exchange the control information in the steps 202 and 206. For example, the cloud entity may perform one instance of the method 200 for each of the RAs, as if there was one virtual RR for each RA. The

information exchanged in the steps 202 and 206 (i.e., the capacities or bit rates provided to the respective UEs in the respective cells involved in the multi connectivity of the respective UEs) are exchange instantaneously, i.e., sent by one of the virtual RRs and received by a different one of the virtual RRs siting inside the cloud entity, e.g., in a datacenter. Thus, no modification is needed in implementing the method 200 to support this centralized case. By means of using this centralized architecture, possible delays between RRs can be reduced or avoided.

The cloud entity computes the one or more shares (e.g., relative resource shares) per UE and per RA according to the step 204 and reports back the one or more computed shares to the pertinent RAs.

In any deployment, e.g., including a one-to-one association between RRs and RAs (e.g., according to the Figs. 3 and 5), an association of multiple RAs to one RR (e.g., according to the Fig. 4) or a cloud implementation (e.g., according to the Fig. 9), the technique can be implemented in a distributed manner, e.g., across several nodes in the RAN 300.

Fig. 10 shows a schematic block diagram for an embodiment of the device 100. The device 100 comprises one or more processors 1004 for performing the method 300 and memory 1006 coupled to the processors 1004. For example, the memory 1006 may be encoded with instructions that implement at least one of the modules 102, 104 and 106.

The one or more processors 1004 may be 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, microcode and/or encoded logic operable to provide, either alone or in

conjunction with other components of the device 100, such as the memory 1006, transmitter functionality. For example, the one or more processors 1004 may execute instructions stored in the memory 1006. Such functionality may include providing various features and steps discussed herein, including any of the benefits disclosed herein. The expression "the device being operative to perform an action" may denote the device 100 being configured to perform the action.

As schematically illustrated in Fig. 10, the device 100 may be embodied by a transmitting station 1000, e.g., functioning as a transmitting base station or a transmitting UE. The transmitting station 1000 comprises a radio interface 1002 coupled to the device 100 for radio communication with one or more receiving stations, e.g., functioning as a receiving base station or a receiving UE.

With reference to Fig. 11, in accordance with an embodiment, a communication system 1100 includes a telecommunication network 1110, such as a 3GPP-type cellular network, which comprises an access network 1111, such as a radio access network, and a core network 1114. The access network 1111 comprises a plurality of base stations 1112a, 1112b, 1112c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 1113a, 1113b, 1113c. Each base station 1112a, 1112b, 1112c is connectable to the core network 1114 over a wired or wireless connection 1115. A first user equipment (UE) 1191 located in coverage area 1113c is configured to wirelessly connect to, or be paged by, the corresponding base station 1112c. A second UE 1192 in coverage area 1113a is wirelessly connectable to the corresponding base station 1112a. While a plurality of UEs 1191, 1192 are illustrated in this example, the disclosed

embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 1112.

Any of the base stations 1112 and the UEs 1191, 1192 may embody the device 100.

The telecommunication network 1110 is itself connected to a host computer 1130, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. The host computer 1130 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 1121, 1122 between the telecommunication network 1110 and the host computer 1130 may extend directly from the core network 1114 to the host computer 1130 or may go via an optional intermediate network 1120. The intermediate network 1120 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 1120, if any, may be a backbone network or the Internet; in particular, the intermediate network 1120 may comprise two or more sub-networks (not shown).

The communication system 1100 of Fig. 11 as a whole enables connectivity between one of the connected UEs 1191, 1192 and the host computer 1130. The connectivity may be described as an over-the-top (OTT) connection 1150. The host computer 1130 and the connected UEs 1191, 1192 are configured to communicate data and/or signaling via the OTT connection 1150, using the access network 1111, the core network 1114, any intermediate network 1120 and possible further infrastructure (not shown) as intermediaries. The OTT connection 1150 may be transparent in the sense that the participating communication devices through which the OTT connection 1150 passes are unaware of routing of uplink and downlink communications. For example, a base station 1112 need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 1130 to be forwarded (e.g., handed over) to a connected UE 1191. Similarly, the base station 1112 need not be aware of the future routing of an outgoing uplink communication originating from the UE 1191 towards the host computer 1130. By virtue of the method 200 being performed by any one of the UEs 1191 or 1192 and/or any one of the base stations 1112, the performance of the OTT connection 1150 can be improved, e.g., in terms of increased throughput and/or reduced latency. More specifically, the host computer 1130 may indicate the AC 302 for the user data being a piece of the data in the multi-layer transmission 208.

Example implementations, in accordance with an embodiment of the UE, base station and host computer discussed in the preceding paragraphs, will now be described with reference to Fig. 12. In a communication system 1200, a host computer 1210 comprises hardware 1215 including a communication interface 1216 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 1200. The host computer 1210 further comprises processing circuitry 1218, which may have storage and/or processing capabilities. In particular, the processing circuitry 1218 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer 1210 further comprises software 1211, which is stored in or accessible by the host computer 1210 and executable by the processing circuitry 1218. The software 1211 includes a host application 1212. The host application 1212 may be operable to provide a service to a remote user, such as a UE 1230 connecting via an OTT connection 1250 terminating at the UE 1230 and the host computer 1210. In providing the service to the remote user, the host application 1212 may provide user data, which is transmitted using the OTT connection 1250. The user data may depend on the location of the UE 1230. The user data may comprise auxiliary information or precision advertisements (also: ads) delivered to the UE 1230. The location may be reported by the UE 1230 to the host computer, e.g., using the OTT connection 1250, and/or by the base station 1220, e.g., using a connection 1260.

The communication system 1200 further includes a base station 1220 provided in a telecommunication system and comprising hardware 1225 enabling it to communicate with the host computer 1210 and with the UE 1230. The hardware 1225 may include a communication interface 1226 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 1200, as well as a radio interface 1227 for setting up and maintaining at least a wireless connection 1270 with a UE 1230 located in a coverage area (not shown in Fig. 12) served by the base station 1220. The communication interface 1226 may be configured to facilitate a connection 1260 to the host computer 1210. The connection 1260 may be direct, or it may pass through a core network (not shown in Fig. 12) of the telecommunication system and/or through one or more intermediate networks outside the

telecommunication system. In the embodiment shown, the hardware 1225 of the base station 1220 further includes processing circuitry 1228, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station 1220 further has software 1221 stored internally or accessible via an external connection.

The communication system 1200 further includes the UE 1230 already referred to. Its hardware 1235 may include a radio interface 1237 configured to set up and maintain a wireless connection 1270 with a base station serving a coverage area in which the UE 1230 is currently located. The hardware 1235 of the UE 1230 further includes processing circuitry 1238, which may comprise one or more

programmable processors, application-specific integrated circuits, field

programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 1230 further comprises software 1231, which is stored in or accessible by the UE 1230 and executable by the processing circuitry 1238. The software 1231 includes a client application 1232. The client application 1232 may be operable to provide a service to a human or non-human user via the UE 1230, with the support of the host computer 1210. In the host computer 1210, an executing host application 1212 may communicate with the executing client application 1232 via the OTT connection 1250 terminating at the UE 1230 and the host computer 1210. In providing the service to the user, the client application 1232 may receive request data from the host application 1212 and provide user data in response to the request data. The OTT connection 1250 may transfer both the request data and the user data. The client application 1232 may interact with the user to generate the user data that it provides.

Any one of the base stations 1220 and 1112 may embody at least one of the RRs 100 and at least one of the RAs 304. The user data may be forwarded by at least one of the base stations using at least one of the legs of any one of the UEs 1191, 1192 and 1230 in the multi-connectivity with the RAN 1111. It is noted that the host computer 1210, base station 1220 and UE 1230 illustrated in Fig. 12 may be identical to the host computer 1130, one of the base stations 1112a, 1112b, 1112c and one of the UEs 1191, 1192 of Fig. 11, respectively. This is to say, the inner workings of these entities may be as shown in Fig. 12, and, independently, the surrounding network topology may be that of Fig. 11.

In Fig. 12, the OTT connection 1250 has been drawn abstractly to illustrate the communication between the host computer 1210 and the UE 1230 via the base station 1220, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the UE 1230 or from the service provider operating the host computer 1210, or both. While the OTT connection 1250 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

The wireless connection 1270 between the UE 1230 and the base station 1220 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 1230 using the OTT connection 1250, in which the wireless connection 1270 forms the last segment. More precisely, the teachings of these embodiments may reduce the latency and improve the data rate and thereby provide benefits such as better responsiveness and improved QoS.

A measurement procedure may be provided for the purpose of monitoring data rate, latency, QoS and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1250 between the host computer 1210 and UE 1230, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 1250 may be implemented in the software 1211 of the host computer 1210 or in the software 1231 of the UE 1230, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 1250 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 1211, 1231 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 1250 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 1220, and it may be unknown or imperceptible to the base station 1220. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host

computer's 1210 measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 1211, 1231 causes messages to be transmitted, in particular empty or "dummy" messages, using the OTT connection 1250 while it monitors propagation times, errors etc.

Fig. 13 is a flowchart illustrating a method implemented in a communication system 1200, in accordance with one embodiment. The communication system 1200 includes a host computer, a base station and a UE which may be those described with reference to Figs. 11 and 12. For simplicity of the present disclosure, only drawing references to Fig. 13 will be included in this paragraph. In a first step 1310 of the method, the host computer provides user data. In an optional substep 1311 of the first step 1310, the host computer provides the user data by executing a host application. In a second step 1320, the host computer initiates a transmission carrying the user data to the UE. In an optional third step 1330, the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional fourth step 1340, the UE executes a client application associated with the host application executed by the host computer.

Fig. 14 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figs. 11 and 12. For simplicity of the present disclosure, only drawing references to Fig. 14 will be included in this paragraph. In a first step 1410 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In a second step 1420, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step 1430, the UE receives the user data carried in the transmission. The technique may be implemented as a method of scheduling a reception and/or a transmission of data on multiple data connections (i.e., through multiple cells) between base stations for the respective cells and multi-connected radio devices (e.g., UEs). The method may comprise at least one of the following steps.

The method may comprise a step of determining an expected amount of radio resources per bit rate or per capacity on one of the data connections (e.g., through the first cell) or (e.g., as an inverse to the afore-mentioned quantity) a bit rate or a capacity per radio resources on the one of the data connections. The expected bit rate or capacity per radio resources may be referred to as quality of the respective connection.

The method may further comprise a step of determining an expected total potential for each connection, e.g., each combination of UE and RA. The expected total potential may comprise a bit rate and/or channel capacity.

The method may further comprise a step of receiving first control information about an additional bit rate or an additional capacity that the radio device is provided or achieves on one or more other data connections of the multi- connectivity. The method may further comprise a step of computing a share of the radio resources on the one data connection based on the quality and the received additional capacity or additional bit rate on the other data connections.

The method may further comprise a step of sending a second control information about the allocated or expected potential (e.g., the allocated or expected capacity or bit rate) that results from the computed share of the radio resources on the one data connection. The second control information may be sent to other instances of the method (e.g., other RRs or base stations also performing the method).

At least one of the steps may be repeated. The method may further comprise a step of scheduling the reception or transmission of data on the multiple connections based on the computed share of the radio resources on the one connection. The exchanged (i.e., received and/or sent) control information about additional capacity or additional bit rate may be an estimate of the achieved bit rate or achieved capacity, e.g., computed as the radio resources allocated to the radio device according to the respective share divided by the expected amount of radio resource per bit rate. The control information may be exchanged using 3GPP XnAP messages or 3GPP X2AP messages.

The computation of the shares may comprise dividing a total share into smaller chunks named step share and iteratively applying rules to control moving or shifting the step shares from one radio device to another radio device.

The rules may be based on a utility function. The computation may depend on a combination of the step share with the utility function. For example, utility increments and utility decrements may be determined. The utility increment is the incremental value of the utility function that would be provided to the RAN in case one additional step share was given to a certain radio device on a given data connection (e.g., in a given cell, radio link or leg of the multi-connectivity). The utility decrement is the decremental value of utility function that would be deducted from the RAN in case one step share was removed from a certain radio device on the given data connection. The step share may be shifted so as to increase or maximize the utility function.

As has become apparent from above description, embodiments of the technique allow reducing computational complexity for a distributed allocation (e.g., scheduling) of radio resources. The embodiments requires only little control information to be exchanged between the involved entities. Preferably, no involvement of the UE in the scheduling decision process is required.

The technique may be compatible with a split-responsibility scheduler, which provides an improved method for scheduling the UEs in mobile communication systems. At least some embodiments enable a split-responsibility scheduler that is completely distributed and can run independently at each RR after the reception of some information of UEs in multi-connectivity from other RRs.

Embodiments of the technique deploy an algorithm for determining the step share exchange based on generic utility functions. A network operator is free to choose any utility functions depending on the targeted objective. Using the utility functions, it is possible to easily incorporate minimum and/or maximum rate requirements as well as a fairness criterion for computing the shares of the radio resources. Examples of utility functions are provided showing how to obtain a global proportional fairness in the RAN or how to meet minimum and/or maximum rate requirements.

After receiving the first control information from one or more other RRs, the complexity involved in the main computation of the algorithm may be

implemented with a complexity that is linear in the number of UEs and the amount of step shares. This complexity is rather low and is only equal to the number of UEs times the amount of step shares in worst-case scenarios.

The technique can be employed in the scenarios comprising UEs in dual- connectivity or UEs have more than two simultaneous data connections.

Many advantages of the present invention will be fully understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the units and devices without departing from the scope of the invention and/or without sacrificing all of its advantages. Since the invention can be varied in many ways, it will be recognized that the invention should be limited only by the scope of the following claims.

Claims

1. A method (200) of controlling an allocation of radio resources in a radio access network, RAN (300), configured to provide multi-connectivity to a radio

device (308-12) through multiple cells (306-1, 306-2) each associated (305-1; 305-2) with a resource allocator, RA (304-1; 304-2), configured to allocate radio resources to the radio device (308-12) in the respective cell (306-1; 306-2), wherein each

RA (304-1; 304-2) is associated (303-1; 303-2) with a resource regulator, RR (100-1; 100-2), configured to control the allocation of the respective radio resources by the respective RA (304-1; 304-2) to the radio device (308-12) according to a share of the respective radio resources in the respective cell (306-1; 306-2), the method (200) comprising or initiating the steps of:

receiving (202), at a first RR (100-1) associated with a first RA (304-1) associated (305-1) with a first cell (306-1) of the multi-connectivity, a first control information (310-1) from a second RR (100-2) associated (303-2) with a second RA (304-2) associated (305-2) with a second cell (306-2) of the multi-connectivity, the first control information (310-1) being indicative of second radio resources (312-2) allocated to the radio device in the second cell; and

controlling (204) the allocation of first radio resources (312-1) to the radio device (308-12) in the first cell (306-1) by computing the share of the first radio resources in the first cell (306-1) depending on the second radio resources (312-2); sending (206), from the first RR (100-1), a second control information (310-2) to the second RR (100-2), the second control information (310-2) being indicative of the first radio resources (312-1) resulting from the computed share.

2. The method of claim 1, wherein the first control information (310-1) comprises a potential of the second radio resources (312-2), and/or the second control information (310-2) comprises a potential of the first radio resources (312-1).

3. The method of claim 2, wherein the potential of the respective radio resources is specific for the radio device (308-12) and/or depends on a radio quality of a radio link for the radio device (308-12) in the respective cell (306-1; 306-2).

4. The method of claim 2 or 3, wherein the potential of the respective radio resources comprises at least one of a channel capacity of the respective radio resources and a number of bits or a bit rate of the respective radio resources.

5. The method of any one of claims 1 to 4, wherein the share is computed using a utility function for the radio device (308-12), wherein the utility function for the radio device (308-12) depends on both the first radio resources and the second radio resources, preferably the utility function for the radio device (308-12) depends on the potential of the first radio resources and the potential of the second radio resources.

6. The method of claim 5, wherein the utility function for the radio device (308-12) depends on at least one of the sum of the first radio resources and the second radio resources and the sum of the potential of the first radio resources and the potential of the second radio resources.

7. The method of claim 5 or 6, wherein the share is computed by increasing or maximizing the sum of the utility function for the radio device and one or more further utility functions for one or more further radio devices, to each of which further first radio resources in the first cell are allocated by the first RA.

8. The method of claim 7, wherein the first radio resources are variable for the increasing or maximizing and the second radio resources are fixed for the increasing or maximizing.

9. The method of claim 7 or 8, wherein the share for the radio device (308-12) is increased by a step share, if an increment of the utility function for the radio device (308-12) due to the step share is greater than a decrement of one of the at least one further utility function for the respective further radio device due to decreasing a further share of the respective further first radio resources for the respective further radio device by the step share.

10. The method of claim 9, wherein the share is increased for the radio device (308-12) by the step share, if the increment of the utility function for the radio device (308-12) due to the step share is greater than an increment of each of the at least one further utility function due to increasing a respective further share of the respective further first radio resources for the respective further radio device by the step share.

11. The method of any one of claims 7 to 10, wherein each further utility function for the respective further radio device depends on the respective further first radio resources allocated to the respective further radio device (308-13) in the first cell (306-1), preferably each further utility function for the respective further radio device (308-13) depends on a potential of the respective further first radio resources.

12. The method of any one of claims 7 to 11, wherein the RAN is configured to provide multi-connectivity to at least one of the one or more further radio devices using the first cell (306-1) and the second cell (306-2), and wherein at least one of: the first control information (310-1) received from the second RR (100-2) is further indicative of further second radio resources allocated to the at least one of the one or more further radio devices by the second RA (304-2) associated with the second RR (100-2); and

the second control information (310-2) sent to the second RR (100-2) is further indicative of the respective further first radio resources allocated to the at least one of the one or more further radio devices by the first RA (304-1) associated with the first RR (100-1).

13. The method of any one of claims 7 to 12, wherein the RAN is configured to provide multi-connectivity to at least one of the one or more further radio devices (308-13) using the first cell (306-1) and a third cell (306-3) associated with a third RA (304-3) associated with a third RR (100-3), the method further comprising or initiating at least one of the steps of:

receiving, at the first RR (100-1), a further first control information from the third RR (100-3), the further first control information being indicative of further second radio resources allocated to the at least one of the one or more further radio devices (308-13) by the third RA (304-3) associated with the third RR (100-3); and sending, from the first RR (100-1), a further second control information to the third RR (100-3), the further second control information being indicative of the respective further first radio resources allocated to the at least one of the one or more further radio devices (308-13) by the first RA (304-1) associated with the first RR (100-1).

14. The method of any one of claims 11 to 13, wherein the first control

information (310-1) and/or the further first control information comprise a potential of the further second radio resources, and/or wherein the second control

information (310-2) and/or the further second control information comprises a potential of the further first radio resources.

15. The method of claim 11 or 14, wherein the potential of the respective radio resources is specific for the respective further radio device (308-13) and/or depends on a radio quality of a radio link for the respective further radio device (308-13) in the respective cell (306-1; 306-3).

16. The method of claim 14 or 15, wherein the potential of the respective radio resources comprises at least one of a channel capacity of the respective further radio resources (308-13) and a number of bits or a bit rate of the respective radio resources.

17. The method of any one of claims 11 or 16, wherein each further utility function for the respective one of the one or more further radio devices (308-13) further depends on the respective further second radio resources allocated to the respective further radio device (308-13), preferably each further utility function for the respective one of the one or more further radio devices (308-13) further depends on a potential of the respective further second radio resources allocated to the respective further radio device (308-13).

18. The method of any one of claims 5 to 17, wherein at least one or each of the utility function and the further utility function is non-linear.

19. The method of claim 18, wherein at least one or each of the utility function and the further utility function comprises at least one of a logarithm and one or more steps.

20. The method of any one of claims 2 to 19, further comprising or initiating the step of:

receiving, at the first RR, a report from the first RA, the report being indicative of a total potential of all radio resources allocated or allocatable in the first cell (306- 1) by the first RA (304-1) for at least one or each of the radio device (308-12) and the one or more further radio devices (308-13).

21. The method of any one of claims 2 to 20, further comprising or initiating the step of:

receiving, at the first RR (100-1), a report from the first RA (304-1), the report being indicative of a radio quality of each of at least one of the first radio resources for the radio device (308-12) in the first cell (306-1) and the further first radio resources for the further radio device (308-13) in the first cell (306-1); and/or

wherein the first control information (310-1) comprises a radio quality of each of at least one of the second radio resources for the radio device (308-12) in the second cell (306-2) and the further second radio resources for the further radio device (308-13) in the second cell (306-2).

22. The method of claim 21, further comprising or initiating at least one of the steps of:

computing the potential of each of at least one of the first radio resources, the second radio resources, the further first radio resources, and the further second radio resources by multiplying an amount of the respective radio resources with the reported radio quality of the respective radio resources; and

computing a total potential of all radio resources allocated or allocatable in the first cell (306-1) by the first RA (304-1) for at least one or each of the radio device (308-12) and the one or more further radio devices (308-13) by multiplying an amount of the all radio resources with the radio quality reported for the respective radio device (308-12; 308-13).

23. The method of any one of claim 20 to 22, wherein the potential of the first radio resources is computed by multiplying the total potential for the radio device (308-12) with the share; and/or wherein the potential of the respective further first radio resources is computed by multiplying the total potential for the respective further radio device (308-13) with the respective further share.

24. The method of any one of claims 1 to 23, wherein the allocation of the respective radio resources comprises scheduling at least one of transmissions to the radio device and receptions from the radio device.

25. The method of any one of claims 1 to 24, further comprising or initiating at least one of the steps of:

comparing (808) a potential, particularly a capacity or a bit rate, of the second radio resources as indicated by the first control information with a potential, particularly a capacity or a bit rate, of the first radio resources;

maintaining (810) respective radio resources providing the greater potential, particular the greater capacity or bit rate, according to the comparison while the potential, particularly the capacity or the bit rate, of the respective radio resources is equal to or less than a maximum potential, particularly a maximum capacity or a maximum bit rate;

reducing (814, 816) the share of the respective radio resources providing the greater potential, particularly the greater capacity or bit rate, according to the comparison if the potential, particularly the capacity or the bit rate, of the respective radio resources is greater than the maximum potential, particularly the maximum capacity or the maximum bit rate; and setting (818) to zero the share of the respective radio resources providing the lesser potential, particular the lesser capacity or bit rate, according to the

comparison.

26. A computer program product comprising program code portions for performing the steps of any one of the claims 1 to 25 when the computer program product is executed on one or more computing devices (1004), optionally stored on a computer-readable recording medium (1006).

27. A device (100; 1000; 1112; 1220) for controlling an allocation of radio resources in a radio access network, RAN (300), configured to provide multi connectivity to a radio device (308-12) through multiple cells (306-1, 306-2) each associated (305-1; 305-2) with a resource allocator, RA (304-1; 304-2), configured to allocate radio resources to the radio device (308-12) in the respective cell (306-1; 306-2), wherein each RA (304-1; 304-2) is associated (303-1; 303-2) with a resource regulator, RR (100-1; 100-2), configured to control the allocation of the respective radio resources by the respective RA (304-1; 304-2) to the radio device (308-12) according to a share of the respective radio resources in the respective cell (306-1; 306-2), the device (100; 1000; 1112; 1220) being configured to perform or initiate the steps of:

28. The device (100; 1000; 1112; 1220) of claim 27, further configured to perform the steps of any one of claims 1 to 25.

29. A device (100; 1000; 1112; 1220) for controlling an allocation of radio resources in a radio access network, RAN (300), configured to provide multi- connectivity to a radio device (308-12) through multiple cells (306-1, 306-2) each associated (305-1; 305-2) with a resource allocator, RA (304-1; 304-2), configured to allocate radio resources to the radio device (308-12) in the respective cell (306-1; 306-2), wherein each RA (304-1; 304-2) is associated (303-1; 303-2) with a resource regulator, RR (100-1; 100-2), configured to control the allocation of the respective radio resources by the respective RA (304-1; 304-2) to the radio device (308-12) according to a share of the respective radio resources in the respective cell (306-1; 306-2), the device (100; 1000; 1112; 1220) comprising at least one processor (1004) and a memory (1006), said memory (1006) comprising instructions executable by said at least one processor (1004), whereby the device (100; 1000; 1112; 1220) is operative to:

receive (202), at a first RR (100-1) associated with a first RA (304-1) associated (305-1) with a first cell (306-1) of the multi-connectivity, a first control information (310-1) from a second RR (100-2) associated (303-2) with a second RA (304-2) associated (305-2) with a second cell (306-2) of the multi-connectivity, the first control information (310-1) being indicative of second radio resources (312-2) allocated to the radio device in the second cell; and

control (204) the allocation of first radio resources (312-1) to the radio device (308-12) in the first cell (306-1) by computing the share of the first radio resources in the first cell (306-1) depending on the second radio resources (312-2);

send (206), from the first RR (100-1), a second control information (310-2) to the second RR (100-2), the second control information (310-2) being indicative of the first radio resources (312-1) resulting from the computed share.

30. The device (100; 1000; 1112; 1220) of claim 29, further operative to perform the steps of any one of claims 1 to 25.

31. A base station (100; 1000; 1112; 1220) configured to communicate with a user equipment, UE, (308; 1191; 1192; 1230), the base station (100; 1000; 1112; 1220) comprising a radio interface and processing circuitry configured to execute the steps of any one of claims 1 to 25.

32. A communication system (300; 1100; 1200) including a host computer (1130; 1220) comprising:

processing circuitry (1218) configured to provide user data; and

a communication interface (1216) configured to forward user data to a cellular network (1220) for transmission to a user equipment, UE, (308; 1191; 1192; 1230), wherein the UE (308; 1191; 1192; 1230) comprises a radio interface (1337) and processing circuitry (1238), wherein the cellular network further includes a base station (100; 1000; 1112; 1220) configured to communicate with the UE (308; 1191; 1192; 1230) and comprising processing circuitry (1228) configured to perform the method of any one of claims 1 to 25.

33. The communication system (300; 1100; 1200) of claim 32, wherein:

the processing circuitry (1218) of the host computer (1130; 1210) is configured to execute a host application (1212), thereby providing the user data; and

the processing circuitry (1238) of the UE (308; 1191; 1192; 1230) is configured to execute a client application (1232) associated with the host application (1212).