TRAFFIC FLOW MANAGEMENT IN A CELLULAR NETWORK
20220191729 · 2022-06-16
Assignee
Inventors
Cpc classification
H04W24/10
ELECTRICITY
H04W28/021
ELECTRICITY
International classification
H04W28/02
ELECTRICITY
Abstract
There is provided a method of managing traffic flows in a cellular network by a traffic flow management node. For each tile of a plurality of tiles of the cellular network, a traffic flow in the tile is measured (200) based on a location and corresponding velocity of at least one user equipment in the cellular network from information provided by the at least one user equipment, subsequent traffic flow in the tile is estimated (202) based on a comparison of the measured traffic flow in the tile to one or more previously measured traffic flows in the tile and an indication of the estimated subsequent traffic flow in the tile is transmitted (204) to a resource management node enabling management of resources related to the traffic flows in at least one tile of the cellular network by said resource management node.
Claims
1. A method of managing traffic flows in a cellular network by a traffic flow management node, the method comprising: for each tile of a plurality of tiles of the cellular network: measuring a traffic flow in the tile based on a location and corresponding velocity of at least one user equipment in the cellular network from information provided by the at least one user equipment; estimating subsequent traffic flow in the tile based on a comparison of the measured traffic flow in the tile to one or more previously measured traffic flows in the tile; and transmitting an indication of the estimated subsequent traffic flow in the tile to a resource management node enabling management of resources related to the traffic flows in at least one tile of the cellular network by said resource management node.
2. The method of claim 1, the method comprising: estimating the subsequent traffic flow in the tile based on one or more spatial differences and/or one or more temporal differences identified by the comparison of the measured traffic flow in the tile to the one or more previously measured traffic flows in the tile.
3. The method of claim 1, the method comprising: using a machine learning algorithm to estimate the subsequent traffic flow in the tile.
4. The method of claim 1, wherein: the estimation of the subsequent traffic flow in the tile is an estimation of the subsequent traffic flow in the tile at a first time; and the method comprises: updating the estimation of the subsequent traffic flow in the tile based on an actual measurement of the traffic flow in the tile at the first time; and transmitting an indication of the updated estimation of the subsequent traffic flow in the tile to the resource management node enabling management of resources related to the traffic flows in at least one tile of the cellular network by said resource management node.
5. The method of claim 1, wherein: the management of resources related to the traffic flows in at least one tile of the cellular network comprises: allocating resources in the at least one tile to manage the traffic flows in the at least one tile; and/or provisioning a quality of service in the at least one tile to manage the traffic flows in the at least one tile.
6. The method of claim 1, wherein said resources comprise resources for vehicle-to-everything, V2X, communication.
7. The method of claim 1, wherein: the plurality of tiles are defined by a grid.
8. The method of claim 1, wherein: the at least one user equipment is served by at least one of a plurality of base stations, each having a coverage area, and wherein the plurality of base stations cover the coverage area of the cellular network.
9. The method of claim 8, wherein: the plurality of tiles of the cellular network span the coverage areas of the plurality of base stations.
10. The method of claim 8, wherein: the coverage areas of the plurality of base stations are overlapping.
11. The method of claim 1, wherein: the information provided by the at least one user equipment is received from the at least one user equipment and/or from at least one location service function node.
12. The method of claim 1, wherein the at least one user equipment comprise one or more vehicles and/or one or more mobile devices.
13. A traffic flow management node configured to perform the method of claim 1.
14. A traffic flow management node comprising: processing circuitry configured to cause the traffic flow management node to: for each tile of a plurality of tiles of the cellular network, measure a traffic flow in the tile based on a location and corresponding velocity of at least one user equipment in the cellular network from information provided by the at least one user equipment and estimate subsequent traffic flow in the tile based on a comparison of the measured traffic flow in the tile to one or more previously measured traffic flows in the tile; and a transmitter, wherein the traffic flow management node is further configured to employ the transmitter to transmit an indication of the estimated subsequent traffic flow in the tile to a resource management node enabling management of resources related to the traffic flows in at least one tile of the cellular network by said resource management node.
15. The traffic flow management node of claim 14, wherein the traffic flow management node is an application server.
16. The traffic flow management node of claim 14, wherein the traffic flow management node is a node of a cellular network or a node outside the cellular network.
17. A method of managing traffic flows in a cellular network by a resource management node, the method comprising: managing resources related to the traffic flows in at least one tile of a plurality of tiles of the cellular network based on an estimated subsequent traffic flow for each tile of the plurality of tiles of the cellular network, wherein the estimated subsequent traffic flow for each tile of the plurality of tiles of the cellular network is based on a comparison of a traffic flow in the tile measured based on a location and corresponding velocity of at least one user equipment in the cellular network to one or more previously measured traffic flows in the tile; and providing the managed resources to one or more user equipments in the at least one tile of the plurality of tiles of the cellular network.
18. The method of claim 17, wherein: the estimated subsequent traffic flow in the tile is an estimation of the subsequent traffic flow in the tile at a first time; and the method further comprises: managing resources related to the traffic flows in at least one tile of the plurality of tiles of the cellular network based on an updated estimation of the subsequent traffic flow for each tile of the plurality of tiles of the cellular network, wherein the updated estimation of the subsequent traffic flow for each tile of the plurality of tiles of the cellular network is based on an actual measurement of the traffic flow in the tile at the first time.
19. The method of claim 17, wherein: managing resources related to the traffic flows in at least one tile comprises: allocating resources in the at least one tile to manage the traffic flows in the at least one tile; and/or provisioning a quality of service in the at least one tile to manage the traffic flows in the at least one tile.
20. A resource management node configured to perform the method of claim 17.
21. A resource management node comprising: processing circuitry for configuring the resource management node to: manage resources related to the traffic flows in at least one tile of a plurality of tiles of the cellular network based on an estimated subsequent traffic flow for each tile of the plurality of tiles of the cellular network, wherein the estimated subsequent traffic flow for each tile of the plurality of tiles of the cellular network is based on a comparison of a traffic flow in the tile measured based on a location and corresponding velocity of at least one user equipment in the cellular network to one or more previously measured traffic flows in the tile; and provide the managed resources to one or more user equipments in the at least one tile of the plurality of tiles of the cellular network.
22-23. (canceled)
24. A non-transitory computer readable medium storing a computer program comprising instructions which, when executed by processing circuitry of a network node, causes the management node to perform the method of claim 1.
25. A non-transitory computer readable medium storing a computer program comprising instructions which, when executed by processing circuitry of a management node, causes the management node to perform the method of claim 17.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] For a better understanding of the idea, and to show how it may be put into effect, reference will now be made, by way of example, to the accompanying drawings, in which:
[0028]
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DETAILED DESCRIPTION
[0040] There is described herein an improved technique for managing traffic flow in a cellular network. The cellular network referred to herein may be a radio access network (RAN) or any other cellular network. The cellular network can, for example, be a fourth generation (4G) cellular network, a fifth generation (5G) cellular network, or any other generation of cellular network.
[0041] The methods described herein may be realized using the vehicle-to-everything (V2X) architecture described in 3GPP TS 23.285 and may also apply to the enhanced 5G V2X architecture described in 3GPP TS 23.287. The methods described herein also apply to application layer models, such as those described in 3GPP TS 23.286, where a V2X application enabler (VAE) client may perform the functions of the at least one user equipment referred to herein and a VAE server may perform the functions of the traffic flow management node referred to herein.
[0042] However, it will be understood that the methods described herein may also be applicable to other cellular network architectures.
[0043]
[0044] As illustrated in
[0045] The at least one user equipment 10 can be configured to connect to the system 100 or, more specifically, to one or more nodes of the system 100. The at least one user equipment 10 is configured to provide (or report) information indicative of a location and corresponding velocity of the at least one user equipment 10. The information indicative of a location and corresponding velocity of the at least one user equipment 10 may also be referred to herein as “traffic flow information”.
[0046] As illustrated in
[0047] The at least one traffic flow management node 20 may be a node of the cellular network, e.g. a node that resides in a mobile network operator (MNO) network. Thus, the at least one traffic flow management node 20 can be a network node according to some embodiments. In some embodiments, the at least one traffic flow management node 20 may be a network data analytics function (NWDAP) node, a policy control function (PCF) node, or a network exposure function (NEF) node. In some of these embodiments, the at least one traffic flow management node 20 may communicate with an application server (e.g. a V2X application server), e.g. over an interface such as over a Nnef interface. In these embodiments, the information from the at least one user equipment 10 may be communicated to the at least one traffic flow management node 20 via the application server. Alternatively, the at least one traffic flow management node 20 may be a node outside the cellular network, such as a node managed by a third party or a third party application function (AF). In some embodiments, for example, the at least one traffic flow management node 20 may itself be an application server, e.g. a V2X application server. The at least one traffic flow management node 20 can be a node providing a service (e.g. a V2X service) to one or more user equipments in the cellular network. The at least one traffic flow management node 20 can interact with the cellular network to perform the functions described herein.
[0048] The system 100 can comprise at least one resource management node 30, which will be described in more detail later with reference to
[0049] Although not illustrated, in some embodiments, the system 100 itself may comprise processing circuitry and at least one memory for storing instructions which, when executed by the processing circuitry, cause the system to operate in accordance with the method described herein for the traffic flow management node 20 and/or the method described herein for the resource management node 30.
[0050] Herein, reference is made to a plurality of tiles of the cellular network. The plurality of tiles may, for example, be defined by a grid. The cellular network is (and thus the cells of the cellular network are) segmented or divided into the plurality of tiles. The plurality of tiles are different to (i.e. do not correspond to) the cells of the cellular network. A tile of the cellular network can span several cells of the cellular network (or parts of them) and a cell of the cellular network can span several tiles of the cellular network (or parts of them). For example, an N to M relation can be provided between cells of the cellular network and tiles of the cellular network. Each tile of the plurality of tiles of the cellular network can correspond to a different geographical area. For example, in some embodiments, each tile of the plurality of tiles of the cellular network may correspond to a different road segment in the cellular network. In some of these embodiments, the cellular network may be represented by a map that is divided into a plurality of tiles, each corresponding to a different road segment. Thus, in some embodiments, each tile of the plurality of tiles may correspond to a road segment. The plurality of tiles make up a traffic flow measurement table. The process described herein can be applied (e.g. iteratively) to small or large geographical areas.
[0051]
[0052] The processing circuitry 22 controls the operation of the traffic flow management node 20 and can implement the method described herein in respect to the traffic flow management node 20. The processing circuitry 22 can comprise one or more processors, processing units, multi-core processors or modules that are configured or programmed to control the traffic flow management node 20 in the manner described herein. In particular implementations, the processing circuitry 22 can comprise a plurality of software and/or hardware modules that are each configured to perform, or are for performing, individual or multiple steps of the method described herein.
[0053] Briefly, the processing circuitry 22 of the traffic flow management node 20 is configured to, for each tile of a plurality of tiles of a cellular network, measure a traffic flow in the tile based on a location and corresponding velocity of at least one user equipment 10 in the cellular network from information provided by the at least one user equipment 10. The processing circuitry 22 of the traffic flow management node 20 is also configured to, for each tile of the plurality of tiles of the cellular network, estimate subsequent traffic flow in the tile based on a comparison of the measured traffic flow in the tile to one or more previously measured traffic flows in the tile, and transmit an indication of the estimated subsequent traffic flow in the tile to a resource management node enabling management of resources related to the traffic flows in at least one tile of the cellular network by the resource management node.
[0054] As illustrated in
[0055] The processing circuitry 22 of the traffic flow management node 20 can be connected to the memory 24 of the traffic flow management node 20. In some embodiments, the memory 24 of the traffic flow management node 20 may be for storing program code or instructions which, when executed by the processing circuitry 22 of the traffic flow management node 20, cause the traffic flow management node 20 to operate in the manner described herein in respect of the traffic flow management node 20. For example, in some embodiments, the memory 24 of the traffic flow management node 20 may be configured to store program code or instructions that can be executed by the processing circuitry 22 of the traffic flow management node 20 to perform the method described herein in respect of the traffic flow management node 20.
[0056] Alternatively or in addition, the memory 24 of the traffic flow management node 20 can be configured to store any requests, responses, indications, information, data, notifications, signals, or similar, that are described herein. The processing circuitry 22 of the traffic flow management node 20 may be configured to control the memory 24 of the traffic flow management node 20 to store any requests, responses, indications, information, data, notifications, signals, or similar, that are described herein.
[0057] In some embodiments, as illustrated in
[0058] Although the traffic flow management node 20 is illustrated in
[0059] It will also be appreciated that
[0060]
[0061] The traffic flow management node 20 described earlier with reference to
[0062] With reference to
[0063] A person skilled in the art will be aware of various way in which to measure traffic flow based on a location and corresponding velocity of at least one user equipment 10 in the cellular network. In some embodiments, for example, measuring a traffic flow in the tile based on a location and corresponding velocity of at least one user equipment 10 in the cellular network may comprise, for each tile of the plurality of tiles of the cellular network, determining a number of user equipments in the tile based on the location of the at least one user equipment 10 in the cellular network and measuring the traffic flow in the tile based on the determined number. Thus, traffic flow can be determined based on the number of user equipments in the tile in some embodiments. The number of user equipments per tile can be referred to as the density of user equipments. Alternatively or in addition, for example, measuring a traffic flow in the tile based on a location and corresponding velocity of at least one user equipment 10 in the cellular network may comprise, for each tile of the plurality of tiles of the cellular network, determining an average velocity of user equipments in the tile based on the velocity of the at least one user equipment in the cellular network and measuring the traffic flow in the tile based on the determined average velocity. Thus, traffic flow can be determined based on an average velocity (and/or the number) of user equipments in the tile in some embodiments.
[0064] In more detail, in a 3GPP network, traffic flow may be measured based on the average velocity V and density p of user equipments. The traffic flow can be measured based on the information collected about the velocity of the user equipments and the number of user equipments in a tile (e.g. using location tracking). The density p of user equipments is the number of user equipments per tile (e.g. per road unit). The traffic flow F may be represented as F.fwdarw.(ρ, V). In a simple form, the traffic flow F can be expressed by the following equation:
F=β.Math.V,
where ρ is the density of user equipments (e.g. the number of user equipments per km) and V is the average velocity of user equipments (e.g. in km/h). Thus, using the information indicative of the location and corresponding velocity of the at least one user equipment, the traffic flow in a certain tile (e.g. on a certain road) can be characterized.
[0065] Returning back to
[0066] At block 204, for each tile of the plurality of tiles of the cellular network, an indication of the estimated subsequent traffic flow in the tile is transmitted to a resource management node enabling management of resources related to the traffic flows in at least one tile of the cellular network by the resource management node. More specifically, the processing circuitry 22 of the traffic flow management node 20 transmits the indication of the estimated subsequent traffic flow in each tile. In some embodiments, the processing circuitry 22 of the traffic flow management node 20 may configured to transmit the indication of the estimated subsequent traffic flow in each tile directly to the resource management node 30. In other embodiments, the processing circuitry 22 of the traffic flow management node 20 may configured to transmit the indication of the estimated subsequent traffic flow in each tile to the resource management node 30 via at least one other node.
[0067] Thus, the transmission of the indication of the estimated subsequent traffic flow to the resource management node enables the management of resources related to the traffic flows in at least one tile of the cellular network by the resource management node. The management of resources related to the traffic flows in at least one tile of the cellular network can, for example, comprise allocating resources in the at least one tile to manage the traffic flows in the at least one tile, provisioning a quality of service (QoS) in the at least one tile to manage the traffic flows in the at least one tile, and/or any other management of resources related to the traffic flows in at least one tile of the cellular network.
[0068] The resources referred to herein can comprise resources for vehicle-to-everything (V2X) communication, or any other resources, or any combination of resources. In the case of resources for V2X communication, the resources may comprise one or more resources for long-range V2X communication, such as communication between a user equipment and a Node B (e.g. over the 3GPP Uu interface). Alternatively or in addition, the resources may comprise one or more resources for short-range V2X communication, such as communication between road users and roadside infrastructure (e.g. over a side-link, such as the 3GPP PC5 interface).
[0069] Although not illustrated in
[0070] In some embodiments involving an updated estimation, the method may also comprise transmitting an indication of the updated estimation of the subsequent traffic flow in the tile to the resource management node enabling management of resources related to the traffic flows in at least one tile of the cellular network by the resource management node. More specifically, the processing circuitry 22 of the traffic flow management node 20 can be configured to transmit the indication of the updated estimation of the subsequent traffic flow in the tile. In some embodiments, the processing circuitry 22 of the traffic flow management node 20 may configured to transmit the indication of the updated estimation of the subsequent traffic flow in the tile directly to the resource management node 30. In other embodiments, the processing circuitry 22 of the traffic flow management node 20 may configured to transmit the indication of the updated estimation of the subsequent traffic flow to the resource management node 30 via at least one other node.
[0071]
[0072] The processing circuitry 32 controls the operation of the resource management node 30 and can implement the method described herein in respect to the resource management node 30. The processing circuitry 32 can comprise one or more processors, processing units, multi-core processors or modules that are configured or programmed to control the resource management node 30 in the manner described herein. In particular implementations, the processing circuitry 32 can comprise a plurality of software and/or hardware modules that are each configured to perform, or are for performing, individual or multiple steps of the method described herein.
[0073] Briefly, the processing circuitry 32 of the resource management node 30 is configured to manage resources related to the traffic flows in at least one tile of a plurality of tiles of a cellular network based on an estimated subsequent traffic flow for each tile of the plurality of tiles of the cellular network. The estimated subsequent traffic flow for each tile of the plurality of tiles of the cellular network is based on a comparison of a traffic flow in the tile measured based on a location and corresponding velocity of at least one user equipment 10 in the cellular network to one or more previously measured traffic flows in the tile. The processing circuitry 32 of the resource management node 30 is also configured to provide the managed resources to one or more user equipments in the at least one tile of the plurality of tiles of the cellular network.
[0074] As illustrated in
[0075] The processing circuitry 32 of the resource management node 30 can be connected to the memory 34 of the resource management node 30. In some embodiments, the memory 34 of the resource management node 30 may be for storing program code or instructions which, when executed by the processing circuitry 32 of the resource management node 30, cause the resource management node 30 to operate in the manner described herein in respect of the resource management node 30. For example, in some embodiments, the memory 34 of the resource management node 30 may be configured to store program code or instructions that can be executed by the processing circuitry 32 of the resource management node 30 to perform the method described herein in respect of the resource management node 30.
[0076] Alternatively or in addition, the memory 34 of the resource management node 30 can be configured to store any requests, responses, indications, information, data, notifications, signals, or similar, that are described herein. The processing circuitry 32 of the resource management node 30 may be configured to control the memory 34 of the resource management node 30 to store any requests, responses, indications, information, data, notifications, signals, or similar, that are described herein.
[0077] In some embodiments, as illustrated in
[0078] Although the resource management node 30 is illustrated in
[0079] It will also be appreciated that
[0080]
[0081] With reference to
[0082] Although not illustrated in
[0083] As also mentioned earlier, managing resources related to the traffic flows in at least one tile of the cellular network can, for example, comprise allocating resources in the at least one tile to manage the traffic flows in the at least one tile, provisioning a quality of service (QoS) in the at least one tile to manage the traffic flows in the at least one tile, and/or any other management of resources related to the traffic flows in at least one tile of the cellular network.
[0084] At block 302, the managed resources are provided to one or more user equipments in the at least one tile of the plurality of tiles of the cellular network. More specifically, the processing circuitry 32 of the resource management node 30 provides the managed resources to one or more user equipments in the at least one tile of the plurality of tiles of the cellular network.
[0085]
[0086] As illustrated by arrow 400 of
[0087] At block 404 of
[0088] As illustrated by arrow 408 of
[0089] At block 414 of
[0090]
[0091] In the illustrated example embodiment of
[0092] For each tile of the plurality of tiles of the cellular network, the subsequent traffic flow in the tile of the plurality of tiles 506 of the cellular network is estimated based on a comparison of the measured traffic flow in the tile of the plurality of tiles 500 of the cellular network to one or more previously measured traffic flows in the tile of the plurality of tiles 502 of the cellular network. That is, in the illustrated example embodiment, for each tile of the plurality of tiles of the cellular network, the measured traffic flow F . . . Fn at a first time t in the tile of the plurality of tiles 500 of the cellular network is compared to the measured traffic flow F . . . Fn at a third time t−1 and at a fourth time t−2 in the tile of a plurality of tiles 502 of the cellular network. Here, the third time t−1 and fourth time t−2 are earlier than the first time t. In some embodiments, the subsequent traffic flow in each tile of the plurality of tiles 506 of the cellular network can be estimated based on one or more spatial differences and/or one or more temporal differences identified by the comparison of the measured traffic flow in the tile of the plurality of tiles 500 of the cellular network to the one or more previously measured traffic flows in the tile of the plurality of tiles 502 of the cellular network. For example, a spatial and/or one or more temporal interpolation may be performed.
[0093] Thus, the subsequent traffic flow at a second time t+1 in each tile of the plurality of tiles 506 of the cellular network is estimated. Although the example embodiment illustrated in
[0094] The method described with reference to
[0095]
[0096] As illustrated in
[0097] The traffic flow measurement described herein can cover multiple base stations 40. In more detail, the at least one user equipment 10 described herein may be served by at least one of a plurality of base stations 40. Each of these base stations 40 has a coverage area. The plurality of base stations 40 may cover the (e.g. entire) coverage area of the cellular network. The plurality of tiles of the cellular network referred to herein can span the coverage areas of the plurality of base stations 40. The coverage areas of the plurality of base stations 40 may be overlapping.
[0098]
[0099]
[0100] The method illustrated in
[0101] With reference to
[0102] At block 804, a prediction error is calculated. The prediction error is calculated as the difference between the predicted traffic flow in the tile at the first time t and the actual measurement of the traffic flow in the tile at the first time t. At block 806, the predicted traffic flow in the tile at the first time t is updated (e.g. corrected) by considering the prediction error. This update can be performed for each tile of the plurality of tiles. In this illustrated example, the traffic flow estimates are provided in a traffic flow measurement table. Thus, at block 806, the predicted traffic flow in the tile at the first time t is updated in the traffic flow table, as illustrated in the traffic flow measurement table 808. In some embodiments, the method described with reference to
[0103]
[0104]
[0105] There is also a computer program comprising instructions which, when executed by processing circuitry (such as the processing circuitry 22, 32 of any of the nodes 20, 30 described earlier), cause the processing circuitry to perform at least part of the method described herein. There is provided a computer program product, embodied on a non-transitory machine-readable medium, comprising instructions which are executable by processing circuitry (such as the processing circuitry 22, 32 of any of the nodes 20, 30 described earlier) to cause the processing circuitry to perform at least part of the method described herein. There is provided a computer program product comprising a carrier containing instructions for causing processing circuitry (such as the processing circuitry 22, 32 of any of the nodes 20, 30 described earlier) to perform at least part of the method described herein. In some embodiments, the carrier can be any one of an electronic signal, an optical signal, an electromagnetic signal, an electrical signal, a radio signal, a microwave signal, or a computer-readable storage medium.
[0106] The node functionality described herein can be performed by hardware. Thus, any one or more of the nodes described herein (e.g. any one or more of the traffic flow management node 20, 1000 and the resource management node 30, 1100) can be a hardware node. However, it will also be understood that at least part or all of the node functionality described herein can be virtualized. For example, the functions performed by any one or more of the nodes can be implemented in software running on generic hardware that is configured to orchestrate the node functionality. Thus, in some embodiments, any one or more of the nodes described herein (e.g. any one or more of the traffic flow management node 20, 1000 and the resource management node 30, 1100) can be a virtual node. In some embodiments, at least part or all of the node functionality described herein may be performed in a network enabled cloud. The node functionality described herein may all be at the same location or at least some of the node functionality may be distributed.
[0107] It will be understood that at least some or all of the method steps described herein can be automated in some embodiments. That is, in some embodiments, at least some or all of the method steps described herein can be performed automatically.
[0108] Thus, in the manner described herein, there is advantageously provided an improved technique for managing traffic flow in a cellular network. It is possible to measure traffic flow in a tile based on information from at least one user equipment 10, which is indicative of a location and corresponding velocity of the at least one user equipment 10, and then predict future traffic flow in the tile based on current and previous traffic flow measurements. There is also advantageously provided a method for updating (e.g. correcting) a subsequent traffic flow estimation based on an actual measurement of the traffic flow in the tile.
[0109] It should be noted that the above-mentioned embodiments illustrate rather than limit the idea, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim, “a” or “an” does not exclude a plurality, and a single processor or other unit may fulfil the functions of several units recited in the claims. Any reference signs in the claims shall not be construed so as to limit their scope.