WO2020013740A1

WO2020013740A1 - A first radio node, a backhaul wireless device and a second radio node and methods therein for enabling wireless backhaul in a wireless communications network

Info

Publication number: WO2020013740A1
Application number: PCT/SE2018/050760
Authority: WO
Inventors: Badawi YAMINE
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2018-07-11
Filing date: 2018-07-11
Publication date: 2020-01-16

Abstract

A method performed in a first radio node (110) for enabling wireless backhaul in a wireless communications network (100) is provided. The first radio node (110) is arranged to communicate with a remote server (153) in the wireless communications network (100). 5 The first radio node (110) detects that a first transmission link (161) adapted for communication with the remote server (153) and established via a network input/output, I/O, port (111) of the first radio node (110) has failed. Also, the first radio node (110) establishes a second transmission link (162) adapted for communication with the remote server (153) via a local I/O port (112) of the first radio node (110), wherein the local I/O 10 port (112) is directly connected to a backhaul wireless device (140) adapted to provide a radio interface connection (141) towards a second radio node (120) in the wireless communications network (100). A first radio node (110) arranged to communicate with a remote server (153) in a wireless communications network (100) is also provided. A backhaul wireless device (140) and a method therein for enabling wireless 15 backhaul in a wireless communications network (100) are also provided. Further, a second radio node (120) and method therein for enabling wireless backhaul in a wireless communications network (100) are also provided. Publ.

Description

A FIRST RADIO NODE, A BACKHAUL WIRELESS DEVICE AND A SECOND RADIO NODE AND METHODS THEREIN FOR ENABLING WIRELESS BACKHAUL IN A WIRELESS COMMUNICATIONS NETWORK

TECHNICAL FIELD

Embodiments herein relate to wireless backhaul in a wireless communications network. In particular, embodiments herein relate to a first radio node and method therein for enabling wireless backhaul in a wireless communications network. Also, embodiments herein relate to a backhaul wireless device and a method therein for enabling wireless backhaul in a wireless communications network. Further, embodiments herein relate to a second radio node and a method therein for enabling wireless backhaul in a wireless communications network.

BACKGROUND

A wireless communications network conventionally comprises radio base stations, also referred to herein as radio nodes, providing radio coverage over at least one respective geographical area forming a so-called cell. Wireless devices, also referred to herein as User Equipments, UEs, mobile stations, and/or wireless terminals, are served in the cells by the respective radio base station. The wireless devices transmit data over an air or radio interface to the radio base stations in uplink, UL, transmissions and the radio base stations transmit data over an air or radio interface to the wireless devices in downlink, DL, transmissions. In today’s wireless communications networks a number of different technologies may be used, such as, for example, 5G/NR, Long Term Evolution (LTE), LTE-Advanced, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications/Enhanced Data rate for GSM Evolution (GSM/EDGE), Worldwide Interoperability for Microwave Access (WiMax), or Ultra Mobile Broadband (UMB), just to mention a few possible technologies for wireless communication.

In any wireless communications network, even though the operator will attempt to create as many redundant transmission links as possible in all parts of the network, there is always a chance that a transmission link, such as, for example, a transmission link between a radio node and the network, will go down or fail.

There may be different reasons why such a transmission link may go down of fail. One reason may be that there may exist different types of cabling and transmission equipments, such as, e.g. microwave transceivers or routers, etc., located between the radio node and the core network node that may fail or brake. For example, an intermediate cabling or transmission equipment might go down or fail due to hardware and/or software issues, or, in case of having microwave transmissions, bad weather. Another reason may be that there is a power outage at the radio node or in the transmission network. For example, a radio node may run out of power in case electricity was cut and possible back-up batteries have run out. A third reason may be human error. For example, each radio node in a wireless communications network is conventionally configured with two Internet Protocol, IP, addresses. One IP address is used to communicate with the Operating Support System, OSS, i.e. an OSS IP, and the other IP address is used to communicate with the other node in the wireless communications network, i.e. a data traffic IP. However, operators of the wireless communications network might every now and then require a change in either of these IP addresses. This may be performed for many different reasons, such as, for example, a network

expansion/reduction or re-homing procedure requiring the network’s IP addresses to be re-designed. For example, in a re-homing procedure, the re-design may mean moving a radio node from one IP subnet to another IP subnet. Due to the manual handling and configuration, there may be mistakes made by an operator when defining these IP addresses for the different nodes.

Conventionally, whenever a radio node goes down or fail in a wireless

communications network, a common solution is to use a Self-Organizing Network, SON, feature. While the SON feature may work well in higher latency networks, such as, e.g.

3G or 4G, this is not the case in a 5G network. In fact, in a 5G network, in case a first radio node goes down or fail, a SON feature may trigger an adjustment of the antennas of neighbouring radio nodes, e.g. the up or down tilt, in order to cover the area or cell of the first radio node. This will most likely result in that some wireless devices served in the area or cell of the first radio node will no longer be covered by the antennas of the neighbouring radio nodes. This may cause some of those wireless devices to either receive radio signals from far distant radio nodes, or be directed to other radio nodes employing a different radio technology, e.g. 3G or 4G, in the same area. The foremost may create interference in the wireless communications network, while the latter may degrade the performance of various 5G applications running in the wireless devices. In addition to those two issues, there is also the issue of capacity in the radio node. In fact, suppose that every radio node in a wireless communications network has a capacity of 300 Watts. According to one example, when a first radio node goes down or fail, the network will be prevented from using the 300 Watts of the first radio node that was designed to cover area or cell of the first radio node, areal . Instead, the SON feature may employ the 300 Watts of a neighbouring radio node to cover both the area or cell of the neighbouring radio node and the area or cell of the first network node. Hence, when a main transmission link goes down or fails in a radio node, a SON feature may not be optimal.

Another common solution consists of using a wireless device, e.g. a mobile phone, being served by the radio node in the wireless communications network as a backhaul transmission link. The wireless device may connect to another wireless device in the wireless communication network and use it as a further relay node for the backhaul transmissions from the radio node. This may then be used as an alternative transmission link by the radio node until the main transmission link toward the network is back in operation.

SUMMARY

It is an object of embodiments herein to enable wireless backhaul in a wireless communications network.

According to a first aspect of embodiments herein, the object is achieved by a method performed in a first radio node for enabling wireless backhaul in a wireless communications network. The first radio node is arranged to communicate with a network node in a wireless communications network. The first radio node detects that a first transmission link adapted for communication with the network node and established via a network input/output, I/O, port of the first radio node has failed. Then, the first radio node establishes a second transmission link adapted for communication with the network node via a local I/O port of the first radio node. Here, the local I/O port is directly connected to a backhaul wireless device adapted to provide a radio interface connection towards a second radio node in the wireless communications network.

According to a second aspect of embodiments herein, the object is achieved by a first radio node for enabling wireless backhaul in a wireless communications network. The first radio node is arranged to communicate with a network node in a wireless

communications network. The first radio node is adapted to detect that a first transmission link adapted for communication with the network node and established via a network I/O port of the first radio node has failed. The first radio node is also adapted to establish a second transmission link adapted for communication with the network node via a local I/O port of the first radio node. Here, the local I/O port is directly connected to a backhaul wireless device adapted to provide a radio interface connection towards a second radio node in the wireless communications network.

According to a third aspect of embodiments herein, the object is achieved by a method performed in a backhaul wireless device for enabling wireless backhaul in a wireless communications network, wherein the backhaul wireless device is adapted to be directly connected to a local I/O port of a first radio node in a wireless communications network. The backhaul wireless device receives, via the local I/O port, information from the first radio node triggering the backhaul wireless device to establish a radio interface connection towards a second radio node in the wireless communications network. Also, the backhaul wireless device establishes a radio interface connection towards the second radio node in the wireless communications network.

According to a fourth aspect of embodiments herein, the object is achieved by a backhaul wireless device for enabling wireless backhaul in a wireless communications network, wherein the backhaul wireless device is adapted to be directly connected to a local I/O port of a first radio node in a wireless communications network. The backhaul wireless device is also adapted to receive, via the local I/O port, information from the first radio node triggering the backhaul wireless device to establish a radio interface connection towards a second radio node in the wireless communications network. The backhaul wireless device is further adapted to establish a radio interface connection towards the second radio node in the wireless communications network.

According to a fifth aspect of embodiments herein, the object is achieved by a method performed by a second radio node for enabling wireless backhaul in a wireless communications network. The second radio node receives, from the backhaul wireless device, information indicating to the second radio node that the radio interface connection towards the backhaul wireless device is to have a higher priority than wireless connections from other wireless devices in the second radio node and/or a minimum guaranteed throughput. Also, the second radio node establishes the radio interface connection towards the backhaul wireless device such that the radio interface connection has a higher priority than wireless connections from other wireless devices in the second radio node and/or a minimum guaranteed throughput. According to a sixth aspect of embodiments herein, the object is achieved by a second radio node for enabling wireless backhaul in a wireless communications network. The second radio node is adapted to receive, from the backhaul wireless device, information indicating to the second radio node that the radio interface connection towards the backhaul wireless device is to have a higher priority than wireless connections from other wireless devices in the second radio node and/or a minimum guaranteed throughput. The second radio node is also adapted to establish the radio interface connection towards the backhaul wireless device such that the radio interface connection has a higher priority than wireless connections from other wireless devices in the second radio node and/or a minimum guaranteed throughput.

According to a seventh aspect of the embodiments herein, a computer program is also provided that is configured to perform the method described above. Further, according to an eight aspect of the embodiments herein, carriers are also provided that are configured to carry the computer program configured for performing the method described above.

By advantageously using the local I/O port of the first radio node, conventionally used only for local Operation and Maintenance, OAM, operations, to provide a wireless backhaul when a main transmission link of the first network node towards the network node via the network input/output, I/O, port has gone down or failed, wireless backhaul in the wireless communications network may be significantly improved. This achieved, for example, by only occupying a single radio resource or bandwidth in the wireless communications network, as compared to the conventional two radio resources or bandwidths according to various prior art solutions.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the embodiments will become readily apparent to those skilled in the art by the following detailed description of exemplary embodiments thereof with reference to the accompanying drawings, wherein:

Fig. 1 is a schematic illustration of a wireless communications network according to some embodiments,

Fig. 2 is another schematic illustration of a wireless communications network according to some embodiments, Fig. 3 is a flowchart depicting embodiments of a method in a first radio node,

Fig. 4 is a flowchart depicting embodiments of a method in a backhaul wireless device,

Fig. 5 is a flowchart depicting embodiments of a method in a second radio node,

Fig. 6 is a block diagram depicting embodiments of a first radio node,

Fig. 7 is a block diagram depicting embodiments of a backhaul wireless device.

Fig. 8 is a block diagram depicting embodiments of a second radio node.

DETAILED DESCRIPTION

The figures are schematic and simplified for clarity, and they merely show details which are essential to the understanding of the embodiments presented herein, while other details have been left out. Throughout, the same reference numerals are used for identical or corresponding parts or steps.

Fig. 1 depicts an example of a wireless communication network 100 in which embodiments herein may be implemented. The wireless communication network 100 may be any wireless system or cellular network, such as a Long Term Evolution (LTE) network, any 3^rd Generation Partnership Project (3GPP) cellular network, Wireless Local Area Network (WLAN/Wi-Fi), a Fourth Generation (4G) or LTE advanced network, a Fifth Generation (5G) or New Radio (NR) network etc.

The wireless communication network 100 may comprise a plurality of radio nodes, whereof three, a first radio node 110 and a second radio node 120, are depicted in the example of Fig. 1. The first radio node 110 and the second radio node 120 may be operative or adapted to serve wireless devices, UE1, UE2, UE3, and UE4, located within their radio coverage, i.e. cell. The wireless devices UE1 , UE2, UE3, and UE4 may here be any type of wireless devices or user equipments (UE) communicating with a network node and/or with another wireless device in a cellular, mobile or radio communication network or system. Examples of such wireless devices are any type of loT enabled devices, mobile phones, cellular phones, Personal Digital Assistants (PDAs), smart phones, tablets, sensors equipped with a UE, Laptop Mounted Equipments (LME) (e.g. USB), Laptop Embedded Equipments (LEEs), Machine Type Communication (MTC) devices, or Machine to Machine (M2M) devices, Customer Premises Equipment (CPE), device-to-device (D2D) wireless devices, wireless devices capable of machine to machine (M2M) communication, etc. The first radio node 110 and the second radio node 120 may also be referred to as network access node or radio base stations, and may, for example, be any one of NodeB, eNodeBs, gNBs, s, Home NodeBs, Home eNodeBs, or Home gNBs, etc. The first radio node 110 and the second radio node 120 may also be any type of local access points, such as, access points for WiFi or WLAN.

Furthermore, according to some embodiments, the first radio node 110 and the second radio node 120 in the wireless communications network 100 may be said to form a Radio Access Network, RAN. In a wireless communications network 100, the RAN is supported by a core network 150. The core network 150 may comprise a number of different network nodes, gateways or entities, such as, for example, Serving Gateways, SGWs, and Packet Data Network, PDN, Gateway, PGWs, for handling user plane data traffic, etc. Optionally, Evolved Packet Gateways or User Plane Functions, EPG/UPF may implement both the SGW and PGW functionality. Other network nodes in the core network 150 may be Mobility Management Entities, MMEs, Operating Support Systems, OSS, etc., but there may also be further core network nodes providing additional functionalities in the core network 150. However, for the sake of simplicity, these functionalities are illustrated in the core network 150 by a first network node 151 and a second network node 152. The first network node 151 may be said to enable user plane data traffic from wireless devices, e.g. UE1 and UE2, served by the first radio node 110 to reach a remote server 153, such as, for example, an application server in a data network, e.g. the Internet. Similarly, the second network node 152 may be said to enable user plane data traffic from wireless devices, e.g. UE3 and UE4, served by the second radio node 120 to reach the remote server 153. The first network node 151 may serve the first radio node 110 in the core network 150 and may be connected to the first radio node

110 via first communication link 131. The second network node 152 may serve the second radio node 120 in the core network 150 and may be connected to the second radio node 120 via second communication link 133. The first and second

communication link 131 and 133 may be established via, for example, a GTP based S1-U interface. The first network node 151 and the second network node 152 may further communicate external to the core network 150 with the remote server 153 over, for example, a Gi/SGi interface.

Furthermore, the first radio node 110 comprises a network input/output, I/O, port 111. The network I/O port 111 is adapted to provide for a main transmission link for the first radio node 110 towards the core network 150 by being connected via the first communication link 131 to the first network node 151. This means that network I/O port

111 is adapted to carry all types of data traffic, i.e. both control and user data, from the first radio node 110 to the core network 150, and vice versa. The network I/O port 111 may be connected to the core network 150 via e.g. a fiber optical cable, an ethernet cable, or a microwave link, etc. As illustrated by the dash arrows in the example of Fig. 2, the main transmission link may be established a first transmission link 161 between the first radio node 110 and the remote server 153. The first network node 110 further comprises a local I/O port 112. The local I/O port 112 is adapted to provide a local access link to the first radio node 110. The local access link via the local I/O port 112 is conventionally only used for performing manual local Operation and Maintenance, OAM, operations on the first radio node 110, such as, e.g. providing node configurations, extracting alarm logs, software upgrades, etc. The local I/O port 112 may, for example, be a passive ethernet port. In some embodiments, the network I/O port 111 and the local I/O port 112 may be part of so-called Digital Unit, DU, in the first radio node 110.

According to some embodiments, the local I/O port 112 of the first radio node 110 may be connected to a backhaul wireless device 140. This may, for example, be performed via a third communication link 132. The third communication link 132 may provide a direct connection to the backhaul wireless device 140. The direct connection may be a wireless or wired one-to-one connection, i.e. a dedicated communication link between the first radio node 110 and the backhaul wireless device 140.

Similarly, the second radio node 120 also comprises a network input/output, I/O, port 121. The network input/output, I/O, port 121 is adapted to provide for a main transmission link for the second radio node 120 towards the core network 150 by being connected via the first communication link 133 to the first network node 152. This means that network input/output, I/O, port 121 is adapted to carry all types of data traffic from the second radio node 120 to the core network 150, and vice versa. The second network node 120 may further comprise a local I/O port 122.

Although embodiments below are described with reference to Fig. 1 , this should not be construed as limiting to the embodiments herein, but merely as an example made for illustrative purposes.

As part of the developing of the embodiments described herein, it has been realized that there are a number of drawbacks with this type of wireless backhaul in a wireless communications network.

One drawback is that there is no specific call establishment cause dedicated for “backhaul wireless devices” in 3GPP standards. Actually, in 3G, 4G and in coming 5G networks, the Radio Resource Control, RRC, protocol is used for the communication between the wireless device and radio node. According to the RRC protocol, each time a wireless device initiates a call, the wireless device inserts in its first RRC message, i.e. a RRC Connection Request, an establishment cause for that call, such as, e.g. data originating from a wireless device. However, according to RRC specifications, there is no RRC establishment cause dedicated to“backhaul wireless devices”. As a result, the communication of the“backhaul wireless devices” might be rejected by a target radio node due to insufficient priority in its establishment cause. This may be illustrated by the following example: Suppose that the main communication link between a network and a first radio node goes down or fails, and that the first radio node then triggers an alternative link to the network via a so-called“backhaul wireless device”. Note that the“backhaul wireless device” in this case, conventionally, is just a normal wireless device that is wirelessly connected to the first radio node. This means that it follows exactly all the rules of other wireless devices also being served by the first radio node. Further suppose that the best cell detected by the“backhaul wireless device’” is a second cell of a neighbouring second radio node. In this case, after the main communication link from the first radio node to the network goes down or fails, the“backhaul wireless device” will establish the alternative communication link to the network via its wireless radio interface through the second cell and the neighbouring second radio node. Since there is no RRC

establishment cause dedicated to“backhaul wireless devices”, the RRC Connection Request will carry any of the existing establishment causes, such as, e.g. data originating from a wireless device. This means that in case the second cell of the neighbouring second radio node is congested there is a significant risk that the connection request from the“backhaul wireless device” will be rejected by the neighbouring second radio node as it does not have any dedicated or special priority to be considered by the neighbouring second radio node. As a consequence, the first radio node will not be able to establish its alternative communication link to the network, and hence the area that was served by the first radio node before the link failure will be left without radio coverage from the first radio node. This means that the three issues mentioned in the background part above will likely be experienced in the wireless communications network.

Another drawback is that conventional wireless backhaul will occupy and be allocated two separate radio resources in the wireless communications network, i.e. one at the source transceiver side between the first radio node and the backhaul wireless device, and one at the target transceiver side between the backhaul wireless device and the neighbouring second radio node. The two transceivers may occupy radio bandwidths from the wireless communications network, e.g. 3G, 4G and 5G networks, and/or radio bandwidths of WiFi networks and/or other technologies. For example, if the source and target transceivers both use a 5G network, then a first radio bandwidth in the cell of the first radio node will be allocated to the source transceiver, and similarly a second radio bandwidth in the cell of the neighbouring second radio node will be allocated to the target transceiver. In other words, in the cells of the first radio node and the neighbouring second radio node, a two certain bandwidths will be spared for the source and target transceivers. This may also result in a high latency for data packets being transmitted first over the radio interface between the first radio to the backhaul wireless device, and then secondly over the radio interface between the backhaul wireless device and the neighbouring second radio node. This aspect may be particularly sensitive for 5G applications requiring very low latency.

Furthermore, some types of communications, such as, e.g. a streaming call, requires a guaranteed minimum bandwidth, whereas other types of calls known as‘best effort’, such as, e.g. normal web browsing or sending/receiving emails, etc., do not need such guaranteed minimum bandwidth. However, this leads to yet another drawback in that while conventional wireless backhaul may trigger a call setup to the neighbouring second radio node that call will come with a guaranteed minimum bandwidth, this guaranteed minimum bandwidth will not change during the complete time span of the communication which may be rather inefficient. For example, during some periods of the day, e.g. night time, there may be 10 wireless device being served by a first radio node employing wireless backhaul via a wireless device having established a backhaul call in the cell of a neighbouring second radio node. At the same time, there may only be 1 wireless device being served in the cell of the neighbouring second radio node. This means that for a conventional wireless backhaul having a fixed‘guaranteed minimum bandwidth’, there is no possible for the neighbouring second radio node to share some extra available bandwidth towards the backhaul wireless device.

These drawbacks are addressed by the embodiments herein by, for example, having a first radio node detect that a first transmission link, established via a network input/output, I/O, port of the first radio node and adapted for communication with the network node, has gone down or failed, and in response establish a second transmission link adapted for communication with the network node via a local I/O port of the first radio node, wherein the local I/O port is directly connected to a backhaul wireless device adapted to provide a radio interface connection towards a second radio node in the wireless communications network. This means that the local I/O port of the first radio node is advantageously used to provide a wireless backhaul, when the main transmission link toward the network node via the network input/output, I/O, port has gone down or failed. Fig. 2 illustrates an example of how a first transmission link 161 , established via the network I/O port 111 of the first radio node 110 towards the first network node 151 in the core network 150 and the remote server 153 in a remote data network, may be replaced upon failure with a second transmission link 162 providing a wireless backhaul to the first radio node 110. The second transmission link 162 is set up via the local I/O port 112 and the backhaul wireless device 140 being connected thereto. The second transmission link 162 is also further set up via the radio interface connection 141 between the backhaul wireless device 140 and the second radio node 120. The second radio node 120 may thus provide access for the second transmission link 162 to the core network 150 via the second network node 152 and its network I/O port 121. Hence, the second transmission link 162 may be established, via the local I/O port 112 and the third communication link 132 with the backhaul wireless device 140 and via the radio interface connection 140 between the backhaul wireless device 140 and the second radio node 120, towards the second network node 152 in the core network 150 and the remote server 153 in a remote data network.

Embodiments of the first radio node 110, the backhaul wireless device 140 and a second radio node 120 and methods therein will be described in more detail below with reference to Figures 3-8.

Example of embodiments of a method performed in a first radio node 110 for enabling wireless backhaul in a wireless communications network 100 will now be described with reference to the flowchart depicted in Fig. 3. The first radio node 110 is arranged to communicate with a remote server 153 in the wireless communications network 100. Fig. 3 is an illustrated example of actions or operations which may be taken by the first radio node 110 in the wireless communication network 100.

Action 301

The first radio node 110 detects that a first transmission link 161 adapted for communication with the remote server 153 and established via a network input/output,

I/O, port 111 of the first radio node 110 has failed. This means that the first radio node 110 detects that the main transmission link of the first radio node 110 has gone down or failed. This first transmission link 161 may carry data traffic related to the Operations Support System, OSS, in the wireless communications network 100, data traffic related to an X2 interface or any other non-critical data traffic, but also critical data traffic, such as, e.g. user data traffic. Action 302

After the detection in Action 301 , the first radio node 110 establishes a second transmission link 162 adapted for communication with the remote server 153 via a local I/O port 112 of the first radio node 110. The local I/O port 112 is directly connected to a backhaul wireless device 140 adapted to provide a radio interface connection 141 towards a second radio node 120 in the wireless communications network 100. In other words, this means that the nature of the local I/O port 112, from being passive and used only to do some Operations and Maintenance, OAM, operations on the first radio node 110, is changed to become a fail-back port which may carry all of the traffic of the first radio node 110 to/from the core network 150 whenever the main transmission link, i.e. the first transmission link 161 , on the network I/O port 111 in the first radio node 110 goes down or fails.

In some embodiments, the first radio node 110 may configure the backhaul wireless device 140 to transmit information indicating to the second radio node 120 that the radio interface connection 141 towards the second radio node 120 is to have a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a minimum guaranteed throughput. This means that each time the backhaul wireless device 140 triggers a call setup, a high priority over existing type of calls and/or a minimum guaranteed throughput will be dedicated to that call setup. This may, for example, be implemented by introducing a new type of establishment cause for a call setup from a backhaul wireless device in the 3GPP Radio Resource Control, RRC, protocol specifications, 3GPP 36.331 , v14.5.0.

Further, according to some embodiments, the first radio node 110 may transmit, after detecting that the first transmission link 161 has failed, information to the backhaul wireless device 140 triggering the backhaul wireless device 140 to establish the radio interface connection 141 towards the second radio node 120. This type of information may trigger the backhaul wireless device 140 to establish the radio interface connection 141 and communicate directly with the second radio node 120 on behalf of the first radio node HO.AIso, the first radio node 110 may, in some embodiments, transmit a utilization level of the first radio node 110 over the radio interface connection 141 to the second radio node 120. This may be perform in order to enable the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection 141 towards the backhaul wireless device 140 to be adjusted based on the utilization level in the first radio node 110. Furthermore, according to some embodiments, in case the first transmission link 161 carried data traffic related to the Operations Support System, OSS, in the wireless communications network 100, data traffic related to an X2 interface or any other non- critical data traffic, the first radio node 110 may await information from the second radio node 120 indicating that a congestion level in the second radio node 120 is below a determined threshold before establishing the second transmission link 162. In other words, if the first transmission link 161 carrying user data traffic goes down or fails, the backhaul wireless device 140 may be, according to some embodiments, required to establish an alternative link via second radio node 120, whereas if the first transmission link 161 that failed only carried OSS data traffic (but the first transmission link 161 carrying user data traffic is still operational), the backhaul wireless device 140 may not have a mandatory need to trigger the alternative link via the backhaul wireless device 140. The same applies for the first transmission link 161 carrying X2 traffic, in which case the first radio node 110 and the second radio node 120 exchange traffic via the X2 link. This is justified when for example the second radio node 120 is congested. In fact, the alternative link over the backhaul wireless device 140 could be postponed for a while until congestion level of second radio node 120 is reduced when the failed first transmission link 161 carries traffic related to OSS, X2 or other non-critical data traffic. However, this should not be done in case the failed first transmission link 161 carries user data traffic, in which case the alternative link over the backhaul wireless device 140 should be a requirement.

Action 303

Optionally, after establishing the second transmission link in Action 302, the first radio node 110 may perform all transmissions towards the remote server 153 over the second transmission link 162. In some embodiments, this may be performed by the first radio node 110 by re-routing data intended for transmission via the network I/O port 111 to the local I/O port 112 in the first radio node 110 when the second transmission link 162 has been established. For example, a software entity or module may be implemented inside the first radio node 110, which may create an internal link between the network I/O port 111 to the local I/O port 112 in the first radio node 110 in a way such that when the first transmission link 161 on the network I/O port 111 goes down or fails, all traffic of the first radio node 110 will be routed to/from the local I/O port 112.

Example of embodiments of a method performed in a backhaul wireless device 140 for enabling wireless backhaul in a wireless communications network 100 will now be described with reference to the flowchart depicted in Fig. 4. The backhaul wireless device 140 is adapted to be directly connected to a local I/O port 112 of a first radio node 110 in the wireless communications network 100. This means that the backhaul wireless device 140 comprise two interfaces. Via a first interface, the backhaul wireless device 140 is connected to the local I/O port 112 of the first radio node 110, e.g. via a dedicated wireless interface or a cable, such as, e.g. an ethernet cable. Via a second interface, the backhaul wireless device 140 is connected to the wireless communications network 100 via a radio. Fig. 4 is an illustrated example of actions or operations which may be taken by the backhaul wireless device 140 in the wireless communication network 100.

Action 401

The backhaul wireless device 140 receives, via the local I/O port 112 of the first radio node 112, information from the first radio node 110 triggering the backhaul wireless device 140 to establish a radio interface connection 141 towards a second radio node 120 in the wireless communications network 100. This means that instead of the backhaul wireless device 140 establishing a radio communication with another remote backhaul wireless device in the wireless communications network 110, as exist according to prior art examples, the backhaul wireless device 140 may be triggered to communicate directly with the second radio node 120. Thus, as a result, only one radio interface bandwidth is allocated for the backhaul wireless device 140 on the cell of the second radio node 120.

Action 402

After receiving the information in Action 401 , the backhaul wireless device 140 establishes a radio interface connection 141 towards the second radio node 120 in the wireless communications network 100. This means that the backhaul wireless device 140 may be used to route the traffic of the first radio node 110 between the local I/O port 112 of the first radio node 110 and the core network 150. In other words, when the network I/O port 111 of the first radio node 110 goes down or fails, the backhaul wireless device 140 will establish via its second interface a call setup with the best cell, i.e. the cell of the second radio node 120. The call setup towards the second radio node 120 may be performed in a similar way as for a normal wireless device in the wireless communications network 100. It should also be noted that the backhaul wireless device 140 may indicate in the call setup whether or not the first transmission link 161 carried data traffic related to the Operations Support System, OSS, in the wireless communications network 100, data traffic related to an X2 interface or any other non-critical data traffic. In some embodiments, the backhaul wireless device 140 may transmit information to the second radio node 120 indicating that the radio interface connection 141 is to have a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a minimum guaranteed throughput. This means that each time the backhaul wireless device 140 triggers a call setup, a high priority over existing type of calls and/or a minimum guaranteed throughput will be dedicated to that call setup. This may, for example, be implemented by introducing a new type of establishment cause for a call setup from a backhaul wireless device in the 3GPP Radio Resource Control, RRC, protocol specifications. This means that the backhaul wireless device 140 may indicate this new type of establishment cause for a call setup in a RRC message to the second network node 120. This may be particularly advantageous when the second radio node 120 is congested, since the backhaul wireless device 140 thus may, with this new ‘prioritized’ type of establishment cause, ensure an establishment of the radio interface connection 121 towards the second radio node 120 no matter what the congestion level is at the second radio node 120. Hence, according to some embodiments, the information may be provided in a Radio Resource Control, RRC, connection establishment procedure with the second radio node 120.

As an illustrative example, when a wireless device in a wireless communication network employing LTE performs any call, then the wireless device will, during the call setup, specify an establishment cause of that call in the first RRC message,

rrcConnection Request. Based on the RRC standard, e.g. 3GPP 36.331 , v15.1 .0 (2018- OS), the wireless device is required to select one of the establishment causes of:

For example, if the wireless device is performing a voice call, then the establishment cause will be mo-VoiceCall-v1280.

Hence, the idea of a new RRC priority dedicated for the backhaul wireless device

140 is advantageous in periods of network congestion. Otherwise, whatever is the establishment cause that is selected by the backhaul wireless device 140, there will be a significant risk that the call setup by the backhaul wireless device 140 may be rejected by a congested second radio node 120. Even in the case where the backhaul wireless device 140 is given the existing highest priority establishment cause, i.e. highPriorityAccess, unless one particular priority is not dedicated to only the backhaul wireless device 140 then the risk of a call setup rejection by the second radio node 120 will be always a valid scenario. In fact, suppose that the highPriorityAccess is given to different categories of wireless devices, i.e. it is given to both backhaul wireless devices and other categories of applications, then if the second radio node 120 is congested, the second radio node 120 does not have any additional criteria to differentiate two types of applications that triggers calls with same establishment cause. As a consequence, the second radio node 120 might reject the call setup from the backhaul wireless device 140, while allowing a call setup of another category to be established. However, if the second radio 120 is congested and all its connected calls are highPriorityAccess, then in case the backhaul wireless device 140 establishes a call towards the second radio node 120, the second radio node 120 will, according to some embodiments, then release one existing highPriorityAccess call and allow the call from the backhaul wireless 140 to get through because the new establishment call of the backhaul wireless device 140 has a higher priority than of highPriorityAccess. In addition, depending on the type of the first transmission link 161 that went down, whether it is a OSS or user data traffic, a sub priority field may be added to the new establishment cause by the backhaul wireless device 140. This may be performed such that, for example, the user data traffic is given highest priority over OSS and X2 data traffic.

In some embodiments, the backhaul wireless device 140 may receive, from the second radio node 120, information indicating an adjusted priority and/or an adjusted minimum guaranteed throughput of the radio interface connection 141. This means that the requested minimum guaranteed throughput by the backhaul wireless device 140 may be is flexible and change depending on the congestion level of neighboring second radio node 120. This is contrary to existing requested minimum guaranteed throughput by wireless device which are conventionally a fixed value that does not changed depending on any level of congestion of a radio node.

Furthermore, according to some embodiments, the backhaul wireless device 140 may transmit data from the first network node 110 over the established radio interface connection 141 towards the second radio node 120 using a determined static IP address of a core network node arranged to operate as a router in the wireless communications network 100. Hence, the backhaul wireless device 140 may establish communication, via the second radio node 120, with a core network node, e.g. the second network node 152 in the core network 150, arranged to operate as a router. Also, in some embodiments, the backhaul wireless device 140 may receive at least one dynamic IP address over the established radio interface connection 141 from the second radio node 120. This means that, due to the call setup with the second radio node 120, the backhaul wireless device 140 will be assigned an IP address by the second radio node 120 and may function more or less like a router from local I/O port 112 of a first radio node 110 to the core network 150 and vice versa. One example of how the backhaul wireless device 140 may route IP packets from the first radio node 110 to the core network 150 is described below.

For example, the backhaul wireless device 140 may exchange, in both direction, information with at least 4 target destinations or network nodes in the core network 150, e.g. an OSS (e.g. for alarms reported by the first radio node 110 to the OSS, etc.), an MME (e.g. for signalling with the core network 150 during call setup of wireless devices being served by the first radio nodel 10, e.g. UE1 and UE2), a SGW (e.g. to send the user data traffic of wireless devices being served by the first radio node 110, e.g. UE1 and UE2) and to neighbouring second radio node 120 (e.g. send a handover request from the first radio node 110 to the second radio node 120 via an X2 link). Here, according to some embodiments, instead of having the backhaul wireless device 140 being configured with different target IPs, i.e. one IP address for each network node or target destination, the backhaul wireless device 140 may be configured with one single target IP address. This single target IP address may correspond to a core network node in the core network 150 arranged to operate as a router for backhaul wireless devices. Thus, the backhaul wireless device 140 may be configured by the operator with a destination IP address corresponding to the core network node arranged to operate as a router for backhaul wireless devices in the core network 150. The core network node is preferably connected beside the PGW of the second radio node 120. Hence, the backhaul wireless device 140 may route IP packets coming from the first radio node 110 to the core network node arranged to operate as a router for backhaul wireless devices in the core network 150, which in turn may forward the received IP packets to their final destination, e.g. an OSS, an MME, an SGW1 , or any neighbouring radio nodes. In the opposite direction, any IP packets coming from an OSS, an MME, an SGW1 , or any neighbouring nodes, may pass by the core network node arranged to operate as a router for backhaul wireless devices in the core network 150. Then, the IP packets may be forwarded via the core network 150 to the second radio node 120, over the radio interface connection 141 of the second radio node 120, and to the backhaul wireless device 140 which will then forward the IP packets via local I/O port 112 to the first network node 110 for processing.

It should also be noted that the backhaul wireless device 140 may connect to the second radio node 120 using any type of wireless communications network technology, such as, e.g. 3G, 4G, 5G, WiFi, via satellite, etc. Suppose that a backhaul wireless device 140 is connected to the first radio node 110 using a first type of wireless communications network technology, and when the main transmission link, i.e. the first transmission link 161 , to/from the first radio node 110 goes down or fails, the backhaul wireless device 140 may connect via the radio interface connection 141 to the second radio node 120 using the same first type of wireless communications network technology or any other wireless communications network technology. However, it should be noted that, whatever is the wireless communications network technology of the first radio node 110 and the second radio node 120, that is, whether they are equal or different, it may be advantageous that both the first radio node 110 and the second radio node 120 belong to the same operator. This is because this will give the operator more control over the functionalities of backhaul wireless device 140.

Example of embodiments of a method performed by a second radio node 120 for enabling wireless backhaul in a wireless communications network 100 will now be described with reference to the flowchart depicted in Fig. 5. Fig. 5 is an illustrated example of actions or operations which may be taken by the second radio node 120 in the wireless communication network 100.

Action 501

The second radio node 120 receives, from a backhaul wireless device 140, information indicating to the second radio node 120 that the radio interface connection 141 towards the backhaul wireless device 140 is to have a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a minimum guaranteed throughput. This means that each time the backhaul wireless device 140 triggers a call setup, a high priority over existing type of calls and/or a dynamic minimum guaranteed throughput may be dedicated by the second radio node 120 to that call setup. This may, for example, be performed by the second radio node 120 receiving from the backhaul wireless device 140 a new type of establishment cause for a call setup from a backhaul wireless device in a RRC protocol message. Hence, according to some embodiments, the information is received in a Radio Resource Control, RRC, connection establishment procedure with the backhaul wireless device 140.

Action 502

After receiving the information in Action 501 , the second radio node 120 may establish the radio interface connection 141 towards the backhaul wireless device 140 such that the radio interface connection 141 has a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a dynamic minimum guaranteed throughput. This means that the second radio node 120 dedicates a higher priority over existing type of calls and/or a dynamic minimum guaranteed throughput to the call setup from the backhaul wireless device 140.

It should also be noted that the second radio node 120 may receive a sub-priority in the call establishment of the backhaul wireless device 140. This means, for example, that if the failure of the first transmission link 151 only includes that links related to the OSS interface, X2 interface, and/or other non-critical data traffic, is lost on the network I/O port 111 on the first radio node 110, then the call setup by the backhaul wireless device 140 on the cell of the second radio node 120 may be assigned a lower priority in comparison to a call setup by the backhaul wireless device 140 on the cell of the second radio node 120 when the failure of the first transmission link 151 includes that the link carrying user data traffic to/from the first radio node 110 is lost on the network I/O port 111 on the first radio node 110. This may be indicated by the backhaul wireless device 140 in the call setup.

In some embodiments, the second radio node 120 may forward at least one dynamic IP address for the backhaul wireless device 140 in the wireless communications network 100. Here, it should be noted that it is the core network 150, normally, a PGW that allocates a dynamic IP address, i.e. one different IP address per call setup, for all the wireless devices in the wireless communications network 100 including the backhaul wireless device 140. The dynamic IP address of the backhaul wireless device 140 is then forwarded, during the call setup, to the second radio node 120. Then, the second radio node 120 will forward the received IP address from the PGW to the backhaul wireless device 140 via the radio interface connection 141.

Action 503

Optionally, after the establishing the radio interface connection in Action 501 , the second radio node 120 may adjust the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection 141 towards the backhaul wireless device 140 based on a congestion level in the second radio node 120. Alternatively, or additionally, the second radio node 120 may also receive a utilization level of a first radio node 110 in the wireless communications network 100 via the radio interface connection 141. In this case, the second radio node 120 may also adjust the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection 141 towards the backhaul wireless device 140 based on the received utilization level. According to some embodiments, the second radio node 120 may also transmit, to the backhaul wireless device 140, information indicating the adjusted priority and/or the dynamic minimum guaranteed throughput of the radio interface connection 141 to the backhaul wireless device 140.

This is exemplified in the following example:

Suppose that the first radio node 110 has a maximum capacity of 120 Mbps and serves only one cell. Also, suppose that the‘guaranteed minimum bandwidth’ required for the backhaul wireless device 140 is 20 Mbps. In order to make the example more relevant, suppose that by coincidence, at night, there are 15 active wireless device communications on the first radio node 110, but only 2 active wireless device

communications on the second radio node 120. Also, these 2 active wireless device communications are non-critical, e.g. two driverless cars parked or moving slowly, whereas the 15 active wireless device communications handled by the first radio node 110 are distributed as follows: 10 active wireless device communications are for driverless cars moving at high speed, 4 active wireless device communications are for normal wireless devices, and the last active wireless device communications corresponds to the backhaul wireless device 140. As a result of this example, the second radio node 120 having by definition 120 Mbps is underutilized as it is serving only two non-critical active wireless device communications. Also, the first radio node 110, which has a maximum link capacity equal to the guaranteed minimum bandwidth of the backhaul wireless device 140 equal to 20 Mbps, has to serve 14 active wireless device communications. On top of that, suppose that additional‘sensitive’ wireless device communications may be activated on the first radio node 110, e.g. a remote health call. According to some embodiments, in order to solve this and other scenarios, the value of the guaranteed minimum bandwidth may be adjusted dynamically depending on utilizations of the first radio node 110 and the second radio node 120 as described above in this action. One detailed example of how this may be performed is described below.

For example, when the first transmission link 161 to the first radio node 110 goes down or fails, the backhaul wireless device 140 establishes a call by selecting best cell in its neighbourhood, here, the cell of the second radio node 120. Once the call is established, the backhaul wireless device 140 may communicate the identity to the cell of the second radio node 120 to the first radio node 110. The first radio node 110 may then check its neighbouring cell database, which is provided to the first radio node 110 and continuously being updated by the OSS, regarding the IP address of second radio node 120. The first radio node 110 may then establish, via the backhaul wireless device 140 and through the radio interface connection 141 in the cell of the second radio node 120, a direct and open communication with the second radio node 120, and start exchanging information about the number and types of calls being handled by the first radio node 110. It should be noted that these transmissions between the first radio node 110 and the second radio node 120 may for example operate exactly as any X2 link between two conventional LTE radio nodes.

It should be noted that different decisions will be then taken depending on the outcome of this open communication. In the example above, e.g. when a remote health communication or call needs to be established on the first radio node 110, the first radio node 110 will request the second radio node 120 to expand the guaranteed minimum bandwidth of its the backhaul wireless device 140. If OK, then the second radio node 120 may adjust the guaranteed minimum bandwidth, e.g. increase it to 40 or 80 Mbps. The second radio node 120 may also communicate this to the backhaul wireless device 140, e.g. via an RRC message, and to the first radio node 110 via the new X2 open link communication established between the first radio node 110 and the second radio node 120, i.e. via the second transmission link 162.

To perform the method actions in a first radio node 110 for enabling wireless backhaul in a wireless communications network 100, wherein first radio node 110 is arranged to communicate with a remote server 153 in the wireless communications network 100, the first radio node 110 may comprise the following arrangement depicted in Fig 6. Fig 6 shows a schematic block diagram of embodiments of a first radio node 110.

The first radio node 110 may comprise processing circuitry 610 and a memory 620. The first radio node 110 may also comprise or be connected to one or more antennas (not shown). The processing circuitry 610 may also comprise a receiving module 611 and a transmitting module 612. The receiving module 611 and the transmitting module 612 may comprise Radio Frequency, RF, circuitry and baseband processing circuitry capable of transmitting a radio signal in the wireless communications network 100. The receiving module 611 and the transmitting module 612 may also form part of a single transceiver. It should also be noted that some or all of the functionality described in the embodiments above as being performed by the first radio node 110 may be provided by the processing circuitry 610 executing instructions stored on a computer- readable medium, such as, e.g. the memory 620 shown in Fig. 6. Alternative

embodiments of the first radio node 110 may comprise additional components, such as, for example, a detecting module 613, establishing module 614, configuring module 615, and an re-routing module 616, each responsible for providing its respective functionality necessary to support the embodiments described herein. The first radio node 110 also comprise a network input/output, I/O, port 111 and a local I/O port 112.

The first radio node 110 or processing circuitry 610 is adapted to, or may comprise the detecting module 613 adapted to, detect that a first transmission link 161 adapted for communication with the remote server 153 and established via a network input/output,

I/O, port 111 of the first radio node 110 has failed. Also, the first radio node 110 or processing circuitry 610 is adapted to, or may comprise the establishing module 614 adapted to, establish a second transmission link 162 adapted for communication with the remote server 153 via a local I/O port 112 of the first radio node 110, wherein the local I/O port 112 is directly connected to a backhaul wireless device 140 adapted to provide a radio interface connection 141 towards a second radio node 120 in the wireless communications network 100.

In some embodiments, the first radio node 110 or processing circuitry 610 may be adapted to, or may comprise the configuring module 615 adapted to, configure the backhaul wireless device 140 to transmit information indicating to the second radio node 120 that the radio interface connection 141 towards the second radio node 120 is to have a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a minimum guaranteed throughput.

In some embodiments, the first radio node 110 or processing circuitry 610 may be adapted to, or may comprise the transmitting module 612 adapted to, transmit, after detecting that the first transmission link 161 has failed, information to the backhaul wireless device 140 triggering the backhaul wireless device 140 to establish the radio interface connection 141 towards the second radio node 120. Also, in some

embodiments, the first radio node 110 or processing circuitry 610 may be adapted to, or may comprise the transmitting module 612 adapted to, transmit a utilization level of the first radio node 110 over the radio interface connection 141 to the second radio node 120. Further, the first radio node 110 or processing circuitry 610 may be adapted to, or may comprise the transmitting module 612 adapted to, perform all transmissions towards the remote server 153 over the second transmission link 162.

Also, in some embodiments, the first radio node 110 or processing circuitry 610 may be adapted to, or may comprise the establishing module 614 adapted to, in case the first transmission link 161 carried data traffic related to the Operations Support System, OSS, in the wireless communications network 100, data traffic related to an X2 interface or any other non-critical data traffic, await information from the second radio node 120 indicating that a congestion level in the second radio node 120 is below a determined threshold before establishing the second transmission link 162.

In some embodiments, the first radio node 110 or processing circuitry 610 may be adapted to, or may comprise the re-routing module 616 adapted to, re-route data intended for transmission via the network I/O port 111 to the local I/O port 112 when the second transmission link 162 has been established. In some embodiments, the network I/O port 111 is adapted to provide a main transmission link for the first radio node 110 towards the remote server 153, and the local I/O port 112 is adapted to provide a local access link to the first radio node 110. Also, in some embodiments, the local I/O port 112 is directly connected to the backhaul wireless device 140 via a wireless or wired one-to-one connection.

Furthermore, the embodiments for enabling wireless backhaul in a wireless communications network 100 described above may be implemented through one or more processing circuitry, such as, e.g. the processing circuitry 610 in the first radio node 110 depicted in Fig. 6, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code or code means for performing the embodiments herein when being loaded into the processing circuitry 610 in the first radio node 110. The computer program code may e.g. be provided as pure program code in the first radio node 110 or on a server and downloaded to the first radio node 110. Thus, it should be noted that the modules of the first radio node 110 may in some embodiments be implemented as computer programs stored in memory, e.g. in the memory modules 620 in Fig. 6, for execution by processing circuitries or processing modules, e.g. the processing circuitry 910 of Fig. 6.

Those skilled in the art will also appreciate that the processing circuitry 610 and the memory 620 described above may refer to a combination of analog and digital circuits, and/or one or more processors configured with software and/or firmware, e.g. stored in a memory, that when executed by the one or more processors such as the processing circuitry 620 perform as described above. One or more of these processors, as well as the other digital hardware, may be included in a single application-specific integrated circuit (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a system- on-a-chip (SoC). To perform the method actions in the backhaul wireless device 140 for enabling wireless backhaul in a wireless communications network 100, the backhaul wireless device 140 may comprise the following arrangement depicted in Fig 7. The backhaul wireless device 140 is adapted to be directly connected to a local I/O port 112 of a first radio node 110 in the wireless communications network 100. Fig 7 shows a schematic block diagram of embodiments of a backhaul wireless device 140.

The backhaul wireless device 140 may comprise processing circuitry 710 and a memory 720. The backhaul wireless device 140 may also comprise or be connected to one or more antennas (not shown). The processing circuitry 610 may also comprise a receiving module 711 and a transmitting module 712. The receiving module 711 and the transmitting module 712 may comprise Radio Frequency, RF, circuitry and baseband processing circuitry capable of transmitting a radio signal in the wireless communications network 100. The receiving module 711 and the transmitting module 712 may also form part of a single transceiver. It should also be noted that some or all of the functionality described in the embodiments above as being performed by the backhaul wireless device 140 may be provided by the processing circuitry 710 executing instructions stored on a computer-readable medium, such as, e.g. the memory 720 shown in Fig. 7. Alternative embodiments of the backhaul wireless device 140 may comprise additional components, such as, for example, an establishing module 713, each responsible for providing its respective functionality necessary to support the embodiments described herein.

The backhaul wireless device 140 or processing circuitry 710 is adapted to, or may comprise the receiving module 711 adapted to, receive, via the local I/O port 112, information from the first radio node 110 triggering the backhaul wireless device 140 to establish a radio interface connection 141 towards a second radio node 120 in the wireless communications network 100. Also, the backhaul wireless device 140 or processing circuitry 710 is adapted to, or may comprise the establishing module 713 adapted to, establish a radio interface connection 141 towards the second radio node 120 in the wireless communications network 100.

In some embodiments, the backhaul wireless device 140 or processing circuitry 710 may be adapted to, or may comprise the transmitting module 712 adapted to, transmit information to the second radio node 120 indicating that the radio interface connection 141 is to have a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a minimum guaranteed throughput. In this case, in some embodiments, the information is provided in a Radio Resource Control, RRC, connection establishment procedure with the second radio node 120. In some embodiments, the backhaul wireless device 140 or processing circuitry 710 may be adapted to, or may comprise the receiving module 711 adapted to, receive, from the second radio node 120, information indicating an adjusted priority and/or a minimum guaranteed throughput of the radio interface connection 141. Also, in some embodiments, the backhaul wireless device 140 or processing circuitry 710 may be adapted to, or may comprise the transmitting module 712 adapted to, transmit data from the first network node 110 over the established radio interface connection 141 towards the second radio node 120 using a determined static IP address of a core network node arranged to operate as a router in the wireless communications network 100. Further, in some embodiments, the backhaul wireless device 140 or processing circuitry 710 may be adapted to, or may comprise the receiving module 711 adapted to, receive at least one dynamic IP address over the established radio interface connection 141 from the second radio node 120. In some embodiments, the backhaul wireless device 140 is directly connected to the local I/O port 112 via a wireless or wired one-to-one connection.

Furthermore, the embodiments for enabling wireless backhaul in a wireless communications network 100 described above may be implemented through one or more processing circuitries, such as, e.g. the processing circuitry 710 in the backhaul wireless device 140 depicted in Fig. 7, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code or code means for performing the embodiments herein when being loaded into the processing circuitry 710 in the backhaul wireless device 140. The computer program code may e.g. be provided as pure program code in the backhaul wireless device 140 or on a server and downloaded to the backhaul wireless device 140. Thus, it should be noted that the modules of the backhaul wireless device 140 may in some embodiments be implemented as computer programs stored in memory, e.g. in the memory modules 720 in Fig. 7, for execution by processing circuitries or processing modules, e.g. the processing circuitry 710 of Fig. 7.

Those skilled in the art will also appreciate that the processing circuitry 710 and the memory 720 described above may refer to a combination of analog and digital circuits, and/or one or more processors configured with software and/or firmware, e.g. stored in a memory, that when executed by the one or more processors such as the processing circuitry 720 perform as described above. One or more of these processors, as well as the other digital hardware, may be included in a single application-specific integrated circuit (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a system- on-a-chip (SoC).

To perform the method actions in second radio node 120 for enabling wireless backhaul in a wireless communications network 100, the second radio node 120 may comprise the following arrangement depicted in Fig 8. Fig 8 shows a schematic block diagram of embodiments of a second radio node 120.

The second radio node 120 may comprise processing circuitry 810 and a memory 820. The second radio node 120 may also comprise or be connected to one or more antennas (not shown). The processing circuitry 810 may also comprise a receiving module 811 and a transmitting module 812. The receiving module 611 and the transmitting module 812 may comprise Radio Frequency, RF, circuitry and baseband processing circuitry capable of transmitting a radio signal in the wireless communications network 100. The receiving module 811 and the transmitting module 812 may also form part of a single transceiver. It should also be noted that some or all of the functionality described in the embodiments above as being performed by the second radio node 120 may be provided by the processing circuitry 810 executing instructions stored on a computer-readable medium, such as, e.g. the memory 820 shown in Fig. 8. Alternative embodiments of the second radio node 120 may comprise additional components, such as, for example, an establishing module 813, and an adjusting module 814, each responsible for providing its respective functionality necessary to support the

embodiments described herein. The second radio node 120 also comprise a network input/output, I/O, port and a local I/O port (not shown).

The second radio node 120 or processing circuitry 810 is adapted to, or may comprise the receiving module 811 adapted to, receive, from a backhaul wireless device 140, information indicating to the second radio node 120 that the radio interface connection 141 towards the backhaul wireless device 140 is to have a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a minimum guaranteed throughput. Also, the second radio node 120 or processing circuitry 810 is adapted to, or may comprise the establishing module 813 adapted to, establish the radio interface connection 141 towards the backhaul wireless device 140 such that the radio interface connection 141 has a higher priority than wireless connections from other wireless devices in the second radio node 120 and/or a dynamic minimum guaranteed throughput. In some embodiments, the information is received in a Radio Resource Control, RRC, connection establishment procedure with the backhaul wireless device 140. In some embodiments, the second radio node 120 or processing circuitry 810 may be adapted to, or may comprise the adjusting module 814 adapted to, adjust the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection 141 towards the backhaul wireless device 140 based on a congestion level in the second radio node 120. Also, in some embodiments, the second radio node 120 or processing circuitry 810 may be adapted to, or may comprise the receiving module 811 adapted to, receive a utilization level of a first radio node 110 in the wireless communications network 100 via the radio interface connection 141. In this case, in some embodiments, the second radio node 120 or processing circuitry 810 may be adapted to, or may comprise the adjusting module 814 adapted to, adjust the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection 141 towards the backhaul wireless device 140 based on the received utilization level.

In some embodiments, the second radio node 120 or processing circuitry 810 may be adapted to, or may comprise the transmitting module 812 adapted to, transmit, to the backhaul wireless device 140, information indicating the adjusted priority and/or the dynamic minimum guaranteed throughput of the radio interface connection 141 to the backhaul wireless device 140. Also, in some embodiments, the second radio node 120 or processing circuitry 810 may be adapted to forward at least one dynamic IP address for the backhaul wireless device 140 in the wireless communications network 100.

Furthermore, the embodiments for enabling wireless backhaul in a wireless communications network 100 described above may be implemented through one or more processing circuitries, such as, e.g. the processing circuitry 810 in the second radio node 120 depicted in Fig. 8, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code or code means for performing the embodiments herein when being loaded into the processing circuitry 810 in the second radio node 120. The computer program code may e.g. be provided as pure program code in the second radio node 120 or on a server and downloaded to the second radio node 120. Thus, it should be noted that the modules of the second radio node 120 may in some embodiments be implemented as computer programs stored in memory, e.g. in the memory modules 820 in Fig. 8, for execution by processing circuitries or processing modules, e.g. the processing circuitry 810 of Fig. 8.

Those skilled in the art will also appreciate that the processing circuitry 810 and the memory 820 described above may refer to a combination of analog and digital circuits, and/or one or more processors configured with software and/or firmware, e.g. stored in a memory, that when executed by the one or more processors such as the processing circuitry 820 perform as described above. One or more of these processors, as well as the other digital hardware, may be included in a single application-specific integrated circuit (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a system- on-a-chip (SoC).

The description of the example embodiments provided herein have been presented for purposes of illustration. The description is not intended to be exhaustive or to limit example embodiments to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of various alternatives to the provided embodiments. The examples discussed herein were chosen and described in order to explain the principles and the nature of various example embodiments and its practical application to enable one skilled in the art to utilize the example embodiments in various manners and with various modifications as are suited to the particular use contemplated. The features of the embodiments described herein may be combined in all possible combinations of methods, apparatus, modules, systems, and computer program products. It should be appreciated that the example embodiments presented herein may be practiced in any combination with each other.

It should be noted that the word“comprising” does not necessarily exclude the presence of other elements or steps than those listed and the words“a” or“an” preceding an element do not exclude the presence of a plurality of such elements. It should further be noted that any reference signs do not limit the scope of the claims, that the example embodiments may be implemented at least in part by means of both hardware and software, and that several“means”,“units” or“devices” may be represented by the same item of hardware.

It should also be noted that the various example embodiments described herein are described in the general context of method steps or processes, which may be implemented in one aspect by a computer program product, embodied in a computer- readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. A computer-readable medium may include removable and non-removable storage wireless devices including, but not limited to, Read Only Memory (ROM), Random Access Memory (RAM), compact discs (CDs), digital versatile discs (DVD), etc. Generally, program modules may include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

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

Therefore, the above embodiments should not be construed as limiting.

Abbreviations

I/O Input/output

IP Internet Protocol

OSS Operating Support System

SON Self-Organizing Network

OAM Operation and Maintenance

DU Digital Unit

GTPU GPRS Tunnelling Protocol for User Plane

HW Hardware

MME Mobility Management Entity

NAS Non-Access Stratum

OSS Operating Support System

PGW Packet Data Gateway

RRC Radio Resource Control

RU Radio Unit

S1 S1 Application Protocol

SGW Serving Gateway

SW Software

X2 X2 Application Protocol

VLAN Virtual Local Area Network

Claims

1. A method performed in a first radio node (110) for enabling wireless backhaul in a wireless communications network (100), wherein the first radio node (110) is arranged to communicate with a remote server (153) in the wireless

communications network (100), the method comprising

detecting (301) that a first transmission link (161) adapted for communication with the remote server (153) and established via a network input/output, I/O, port (111) of the first radio node (110) has failed; and

establishing (302) a second transmission link (162) adapted for communication with the remote server (153) via a local I/O port (112) of the first radio node (110), wherein the local I/O port (112) is directly connected to a backhaul wireless device (140) adapted to provide a radio interface connection (141) towards a second radio node (120) in the wireless communications network (100).

2. The method according to claim 1 , further comprising configuring the backhaul wireless device (140) to transmit information indicating to the second radio node (120) that the radio interface connection (141) towards the second radio node (120) is to have a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a minimum guaranteed throughput.

3. The method according claim 1 or 2, further comprising transmitting, after detecting that the first transmission link (161) has failed, information to the backhaul wireless device (140) triggering the backhaul wireless device (140) to establish the radio interface connection (141) towards the second radio node (120).

4. The method according to any of claims 1-3, further comprising transmitting a

utilization level of the first radio node (110) over the radio interface connection (141) to the second radio node (120).

5. The method according to any of claims 1-4, further comprising performing all

transmissions towards the remote server (153) over the second transmission link (162).

6. The method according to any of claims 1-5, further comprising, in case the first transmission link (161) carried data traffic related to the Operations Support System, OSS, in the wireless communications network (100), data traffic related to an X2 interface or any other non-critical data traffic, awaiting information from the second radio node (120) indicating that a congestion level in the second radio node

(120) is below a determined threshold before establishing the second transmission link (162).

7. The method according to any of claims 1-6, further comprising re-routing data intended for transmission via the network I/O port (111) to the local I/O port (112) when the second transmission link (162) has been established.

8. A first radio node (110) for enabling wireless backhaul in a wireless

communications network (100), wherein first radio node (110) is arranged to communicate with a remote server (153) in the wireless communications network (100), the first radio node (110) being adapted to

detect that a first transmission link (161) adapted for communication with the remote server (153) and established via a network input/output, I/O, port (111) of the first radio node (110) has failed, and establish a second transmission link (162) adapted for communication with the remote server (153) via a local I/O port (112) of the first radio node (110), wherein the local I/O port (112) is directly connected to a backhaul wireless device (140) adapted to provide a radio interface connection (141) towards a second radio node (120) in the wireless communications network (100).

9. The first radio node (110) according to claim 8, further adapted to configure the backhaul wireless device (140) to transmit information indicating to the second radio node (120) that the radio interface connection (141) towards the second radio node (120) is to have a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a minimum guaranteed throughput.

10. The first radio node (110) according claim 8 or 9, further adapted to transmit, after detecting that the first transmission link (161) has failed, information to the backhaul wireless device (140) triggering the backhaul wireless device (140) to establish the radio interface connection (141) towards the second radio node (120).

11. The first radio node (110) according to any of claims 8-10, further adapted to

transmit a utilization level of the first radio node (110) over the radio interface connection (141) to the second radio node (120).

12. The first radio node (110) according to any of claims 8-11 , further adapted to

perform all transmissions towards the remote server (153) over the second transmission link (162).

13. The first radio node (110) according to any of claims 8-12, further adapted to, in case the first transmission link (161) carried data traffic related to the Operations Support System, OSS, in the wireless communications network (100), data traffic related to an X2 interface or any other non-critical data traffic, await information from the second radio node (120) indicating that a congestion level in the second radio node (120) is below a determined threshold before establishing the second transmission link (162).

14. The first radio node (110) according to any of claims 8-13, further adapted to re route data intended for transmission via the network I/O port (111) to the local I/O port (112) when the second transmission link (162) has been established.

15. The first radio node (110) according to any of claims 8-14, wherein the network I/O port (111) is adapted to provide a main transmission link for the first radio node (110) towards the remote server (153), and the local I/O port (112) is adapted to provide a local access link to the first radio node (110).

16. The first radio node (110) according to any of claims 8-15, wherein the local I/O port (112) is directly connected to the backhaul wireless device (140) via a wireless or wired one-to-one connection.

17. The first radio node (110) according to any of claims 10-18, comprising at least one processing circuitry (1010) and a memory (1020), wherein the memory (1020) is containing instructions executable by the at least one processing circuitry (1010).

18. A method performed in a backhaul wireless device (140) for enabling wireless backhaul in a wireless communications network (100), wherein the backhaul wireless device (140) is adapted to be directly connected to a local I/O port (112) of a first radio node (110) in the wireless communications network (100), the method comprising

receiving (401), via the local I/O port (112), information from the first radio node (110) triggering the backhaul wireless device (140) to establish a radio interface connection (141) towards a second radio node (120) in the wireless communications network (100); and

establishing (402) a radio interface connection (141) towards the second radio node (120) in the wireless communications network (100).

19. The method according to claim 18, further comprising transmitting information to the second radio node (120) indicating that the radio interface connection (141) is to have a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a minimum guaranteed throughput.

20. The method according to claim 19, wherein the information is provided in a Radio Resource Control, RRC, connection establishment procedure with the second radio node (120).

21. The method according to any of claims 18-20, further comprising receiving, from the second radio node (120), information indicating an adjusted priority and/or a minimum guaranteed throughput of the radio interface connection (141).

22. The method according to any to claims 18-21 , further comprising transmitting data from the first network node (110) over the established radio interface connection (141) towards the second radio node (120) using a determined static IP address of a core network node arranged to operate as a router in the wireless

communications network (100).

23. The method according to any to claims 18-22, further comprising receiving at least one dynamic IP address over the established radio interface connection (141) from the second radio node (120).

24. A backhaul wireless device (140) for enabling wireless backhaul in a wireless communications network (100), wherein the backhaul wireless device (140) is adapted to be directly connected to a local I/O port (112) of a first radio node (110) in the wireless communications network (100), the backhaul wireless device (140) being adapted to

receive, via the local I/O port (112), information from the first radio node (110) triggering the backhaul wireless device (140) to establish a radio interface connection (141) towards a second radio node (120) in the wireless

communications network (100), and establish a radio interface connection (141) towards the second radio node (120) in the wireless communications network (100).

25. The backhaul wireless device (140) according to claim 24, further adapted to

transmit information to the second radio node (120) indicating that the radio interface connection (141) is to have a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a minimum guaranteed throughput.

26. The backhaul wireless device (140) according to claim 25, wherein the information is provided in a Radio Resource Control, RRC, connection establishment procedure with the second radio node (120).

27. The backhaul wireless device (140) according to any of claims 24-26, further adapted to receive, from the second radio node (120), information indicating an adjusted priority and/or a minimum guaranteed throughput of the radio interface connection (141).

28. The backhaul wireless device (140) according to any to claims 24-27, further adapted to transmit data from the first network node (110) over the established radio interface connection (141) towards the second radio node (120) using a determined static IP address of a core network node arranged to operate as a router in the wireless communications network (100).

29. The backhaul wireless device (140) according to any to claims 24-28, further adapted to receive at least one dynamic IP address over the established radio interface connection (141) from the second radio node (120).

30. The backhaul wireless device (140) according to any of claims 24-29, wherein the backhaul wireless device (140) is directly connected to the local I/O port (112) via a wireless or wired one-to-one connection.

31. The backhaul wireless device (140) according to any of claims 24-30, comprising at least one processing circuitry (1110) and a memory (1120), wherein the memory (1120) is containing instructions executable by the at least one processing circuitry (1110).

32. A method performed by a second radio node (120) for enabling wireless backhaul in a wireless communications network (100), the method comprising

receiving (501), from a backhaul wireless device (140), information indicating to the second radio node (120) that the radio interface connection (141) towards the backhaul wireless device (140) is to have a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a dynamic minimum guaranteed throughput; and

establishing (502) the radio interface connection (141) towards the backhaul wireless device (140) such that the radio interface connection (141) has a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a dynamic minimum guaranteed throughput.

33. The method according to claim 32, wherein the information is received in a Radio Resource Control, RRC, connection establishment procedure with the backhaul wireless device (140).

34. The method according to claim 32 or 33, further comprising

adjusting (503) the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection (141) towards the backhaul wireless device (140) based on a congestion level in the second radio node (120).

35. The method according to any of claims 32-34, further comprising receiving a utilization level of a first radio node (110) in the wireless communications network (100) via the radio interface connection (141), and adjusting (503) the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection (141) towards the backhaul wireless device (140) based on the received utilization level.

36. The method according to claim 34 or 35, further comprising transmitting, to the backhaul wireless device (140), information indicating the adjusted priority and/or the dynamic minimum guaranteed throughput of the radio interface connection (141) to the backhaul wireless device (140).

37. The method according to any of claims 32-36, further comprising forwarding at least one dynamic IP address for the backhaul wireless device (140) in the wireless communications network (100).

38. A second radio node (120) for enabling wireless backhaul in a wireless

communications network (100), the second radio node (120) being adapted to receive, from a backhaul wireless device (140), information indicating to the second radio node (120) that the radio interface connection (141) towards the backhaul wireless device (140) is to have a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a minimum guaranteed throughput, and establish the radio interface connection (141) towards the backhaul wireless device (140) such that the radio interface connection (141) has a higher priority than wireless connections from other wireless devices in the second radio node (120) and/or a dynamic minimum guaranteed throughput.

39. The second radio node (120) according to claim 38, wherein the information is received in a Radio Resource Control, RRC, connection establishment procedure with the backhaul wireless device (140).

40. The second radio node (120) according to claim 38 or 39, further adapted to adjust the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection (141) towards the backhaul wireless device (140) based on a congestion level in the second radio node (120).

41. The second radio node (120) according to claim 40, further adapted to receive a utilization level of a first radio node (110) in the wireless communications network (100) via the radio interface connection (141), and adjust the priority and/or the dynamic minimum guaranteed throughput of the radio interface connection (141) towards the backhaul wireless device (140) based on the received utilization level.

42. The second radio node (120) according to claim 40 or 41 , further adapted to

transmit, to the backhaul wireless device (140), information indicating the adjusted priority and/or the dynamic minimum guaranteed throughput of the radio interface connection (141) to the backhaul wireless device (140).

43. The second radio node (120) according to any of claims 38-42, further adapted to forward at least one dynamic IP address for the backhaul wireless device (140) in the wireless communications network (100).

44. The second radio node (120) according to any of claims 38-43, comprising at least one processing circuitry (1210) and a memory (1220), wherein the memory (1220) is containing instructions executable by the at least one processing circuitry (1210).

45. A computer program product, comprising instructions which, when executed on at least one processing circuitry (1010; 1110; 1210), cause the at least one processing circuitry (1010; 1110; 1210) to carry out the method according to any of claims 1-9, 18-23, or 32-37.

46. A carrier containing the computer program product according to claim 45, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer- readable storage medium.