ADAPTING INTEGRATED ACCESS AND BACKHAUL NODE CELL COVERAGE

Methods and apparatus are provided for adapting a serving cell capacity of an integrated access and backhaul, IAB, node serving one or more wireless devices. In one embodiment a method is performed by the IAB node. The method includes determining a value corresponding to a backhaul link capacity, adapting, based on the determined value, a power level of the serving cell and signalling, to one or more served wireless devices, information indicative of the adapted serving cell power level.

TECHNICAL FIELD

Embodiments herein relate generally to integrated access and backhaul nodes and, in particular, to adapting cell coverage.

BACKGROUND

In 3rd Generation Partnership Project (3GPP) Rel-16 time frame potential solutions for efficient operation of integrated access and wireless access backhaul (IAB) in new radio (NR) are studied in IAB study item/work item. In the studied scenarios, an IAB network comprising several IAB nodes and UEs served by these IAB nodes. The data routing is performed across IAB nodes. The 3GPP Rel-15 functionalities are assumed as baseline for any potential enhancement

Densification via the deployment of more and more base stations (macro or micro base stations) is one of the mechanisms that can be employed to satisfy the ever-increasing demand for bandwidth/capacity in mobile networks. Due to the availability of more spectrum in the millimeter wave (mmw) band, deploying small cells that operate in this band is an attractive deployment option for these purposes. However, deploying fibre to the small cells, which is the usual way in which small cells are deployed, can end up being very expensive and impractical. Thus, employing a wireless link for connecting the small cells to the operator's network is a cheaper and practical alternative. One such solution is an Integrated Access and Backhaul (IAB) network, where the operator can utilize part of the radio resources for the backhaul link.

InFIG.1, an example IAB deployment is presented, where the IAB donor node (in short IAB donor) has a wired connection to the core network and the IAB relay nodes (in short IAB nodes) are wirelessly connected using NR to the IAB donor, either directly or indirectly via another IAB node. The connection between IAB donor/node and UEs is called access link, whereas the connection between two IAB nodes or between an IAB donor and an IAB node is called backhaul link. The example shows two IAB nodes but in other examples only one IAB node may be deployed or multiple IAB hops or backhaul links.

Referring toFIG.2, the adjacent upstream node which is closer to the IAB donor node of an IAB node may be referred to as a parent node of the IAB node. The adjacent downstream node which is further away from the IAB donor node of an IAB node may be referred to as a child node of the IAB node. The backhaul link between the parent node and the IAB node may thus be referred to as the parent (backhaul) link, whereas the backhaul link between the IAB node and the child node may be referred to as a child (backhaul) link.

FIG.3depicts a baseline User Plane (UP) Protocol stack for IAB in 3GPP Rel-16. During the study item phase of the IAB work (summary of the study item can be found in the technical report TR 38.874 V16.0.0 (2019-01-10)), it was agreed to adopt a solution that leverages the Central Unit (CU)/Distributed Unit (DU) split architecture of NR. Hence, an IAB node consist of a DU part, which serves UEs and possible other so-called child IAB nodes, and a MT part, which handles the backhaul link towards another IAB (DU) node or the IAB (DU) donor.

In this architecture, each IAB-node includes a Mobile Termination (MT) and a distributed unit (DU). In an IAB node, the MT function is a logical unit which terminates the backhaul radio interface toward the IAB parent node. Via the MT, the IAB-node connects to an upstream IAB-node or the IAB-donor. Via the DU, the IAB-node establishes radio link control (RLC)-channels to UEs and to MTs of downstream IAB-nodes. For MTs, this RLC-channel may refer to a modified RLC, denoted RLC*. An IAB-node can connect to more than one upstream IAB-node or IAB-donor DU. The IAB-node may contain multiple DUs, but each DU part of the IAB-node has one F1-C connection only with one IAB-donor CU-CP.

The donor node also includes a DU to support UEs and MTs of downstream IAB-nodes. The IAB-donor includes one or more CU for the DUs of all IAB-nodes and for its own DU. It is assumed that the DUs on an IAB-node are served by or connected to only one IAB-donor. This IAB-donor node may change through topology adaptation. Each DU of an IAB-node connects to the CU in the IAB-donor using a modified form of F1, which is referred to as F1*. F1*-U runs over RLC channels on the wireless backhaul between the MT on the IAB-node and the DU on the donor. An adaptation layer is added, which holds routing information, enabling forwarding. It replaces the IP functionality of the standard F1-stack. F1*-U may carry a GPRS tunneling protocol user plane (GTP-U) header for the end-to-end association between CU and DU. In a further example, information carried inside the GTP-U header may be included into the adaption layer.

With reference toFIG.4, the chosen protocol stacks reuse the current CU-DU split as specified in Rel-15, where the full user plane F1-U (GTP-U/UDP/IP) is terminated at the IAB node (like a normal DU) and the full control plane F1-C (F1-AP/SCTP/IP) is also terminated at the IAB node (like a normal DU). In the cases a), b) and c), depicted inFIG.4, Network Domain Security (NDS) is assumed to protect both UP and CP traffic (IPsec in the case of UP, and DTLS in the case of CP). IPsec could also be used for the CP protection instead of DTLS (in this case no DTLS layer would be required).

A new layer, called adaptation layer has been introduced in the IAB nodes and the IAB donor, which is used for routing of packets to the appropriate downstream/upstream node and also mapping the UE bearer data to the proper backhaul RLC channel (and also between ingress and egress backhaul RLC channels in intermediate IAB nodes) to satisfy the end to end QoS requirements of bearers.

The radio resource control (RRC) connection for the IAB node is between the MT and the CU-CP, which is also the case for the UEs connected to the IAB (DU). A UE in active mode performs measurements in order to provide the network with its current radio conditions. These measurements are used in the current transfer of user data and in the management and configuration of the system. The same applies to the MT of the IAB node. Hence, measurement reports are processed in the CU-CP.

In the case of inter-CU topology adaptation due to deteriorating radio link quality of the backhaul link of an IAB node (the link between the MT and the IAB-donor or parent IAB node (IAB DU) in case of multi-hop), the current approach in TR 38.874 is to discontinue service when the migrating IAB-node's MT connects to the target CU during Inter-gNB handover since it loses connectivity to its source CU. Consequently, UEs connected to this DU observe radio link failure (RLF). The UE will suffer from RLF and must perform RRC reconnection establishment in case of inter-CU topology adaptation.

In the case of intra-CU topology adaptation due deteriorating radio link quality of an IAB node there may not be an RLF if the handover is successful.

In NR Rel-15, as captured in the 3GPP TS 38.213 V15.10.0 (2020 Jul. 17), a UE estimates the DL pathloss based on the formula:

where referenceSignalPower is provided by higher layers and RSRP is the reference signal received power, defined in 3GPP TS 38.215 V15.7.0 (2020 Jul. 14) for the reference serving cell and the higher layer filter configuration provided by QuantityConfig is defined in 3GPP TS 38.331 V15.10.0 (2020 Jul. 24) for the reference serving cell.

If the UE is not configured for periodic channel state information-reference signal (CSI-RS) reception, referenceSignalPower is provided by ss-PBCH-BlockPower (included in the System Information block message which is broadcasted periodically). If the UE is configured for periodic CSI-RS reception, referenceSignalPower is provided either by ss-PBCH-BlockPower or by powerControlOffsetSS (via RRC signaling) providing an offset of the CSI-RS transmission power relative to the SS/PBCH block transmission power in 3GPP TS 38.214 V15.10.0 (2020 Jul. 17). If powerControlOffsetSS is not provided to the UE, the UE assumes an offset of 0 dB.

The DL pathloss PL described above is used in the UL power control in LTE and NR. In brief, the UL power per subband (PSD) is updated as

The parameter a is the fractional pathloss compensation factor (1.0 means total compensation).

P0 is calculated like this:

Typical numbers of the above parameters are M0=6 (default number of resource blocks), noiseRise=0 dB, lin2db(noisePowerPerSubband)=5 dB over noise floor (i.e. −146 dB per subband of 180 KHz), sinrTarget=12.6 dB and alfa (a)=0.8. The interpretation of the PO equation above is that a UE with Ptx=Pmax and using M=M0 subbands (or resource blocks (RBs)) will be able to reach the desired target SINRO (which is equal to sinrTarget above).

Decreasing PO causes lower user transmit power and can be achieved by decreasing the sinrTarget (SINRO) or increasing the MO.

In patent application PCT/SE2020/050269, “Mobility mechanism based on backhaul warning bit for IAB”, the IAB node may use a ‘warning’ message targeting all UEs connected downwards to trigger measurements which would be reported to the CU-UP. Although this is a non-complex solution it may have at least one drawback in increased measurement reporting.

SUMMARY

A mechanism to adapt the access link capacity based on the backhaul link quality is proposed. Each IAB node monitors their respective backhaul link quality. The IAB node adjusts its downlink transmission power for each SS/PBCH block on the downstream link according to the measured backhaul (BH) link quality indication to trigger UEs to HO to other nodes. This is repeated as long as the IAB access link throughput is higher than backhaul link capacity or a minimum downlink transmission power is reached.

As a second step if the IAB access link throughput is higher than the backhaul link capacity, the Cell-ULPC-OFFSET is adjusted to bring down the bit rate of selected high bit rate UEs.

In case a BH link radio quality becomes bad, which has a risk to cause BH RLF on the BH link of a path/route, the other hops (at least downstream links) of the path/route are adjusted accordingly to be aligned with the reduced BH link capacity.

The adjustment ensures that a portion of the cell edge UEs can perform timely recovery actions (such as handover) and if needed high bit-rate UEs reduce their UL bitrate. The main advantage with the latter is that by decrease users UL bitrate we both adapt to the BH available capacity and lower the interference in the IAB cell. Both these actions mean that we in fact shrink the cell coverage in both the DL and the UL and avoid that UEs trigger RLF.

The following benefits may be achieved:1) IAB node can take proper recovery actions for the BH RLF in good time to reduce latency2) avoiding flooding other links with signaling distribution. With this approach we will have a natural selection of targeting the cell edge users.3) Using proposed MAC CE and/or DCI based signaling alternative, the IAB node of the concerned BH link can signal the relevant UEs of change of the synchronization reference signals and/or the cell-ulpc-offset in a timely manner. In a first aspect a method is performed by an integrated access and backhaul, IAB, node for adapting a serving cell capacity. The method comprising determining a value corresponding to a backhaul link capacity, adapting, based on the determined value, a power level of the serving cell and signalling, to one or more served wireless devices, information indicative of the adapted serving cell power level. In some examples of this aspect the power level comprises a reference signal power level. The reference In some examples the signalled information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level indicative to the one or more wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level. In some examples the signalling information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the one or more wireless devices are determined to be within than a predefined distance from the served cell and/or with a radio channel quality above a certain level. In some examples, the method includes sending to one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices. The transmit power level parameter may be a cell uplink power control offset to be applied to a power per sub-band calculation to be performed by the one or more wireless devices, causing a per wireless device reduction in uplink transmit power. In some examples the transmit power level parameter is comprised in a MAC CE. In some examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI. In some examples the one or more wireless devices are determined to correspond to high data rate users. In some examples the method further comprises determining a second value corresponding to the backhaul link capacity and sending to a further one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices based on the determined second value corresponding to the backhaul link capacity. In some examples the signalled information and/or signalled transmit power level further comprises a backhaul link identifier. In some examples the wireless device is an IAB node.

In another aspect, a method is performed by a wireless device served by an integrated access and backhaul, IAB, node. The method comprising receiving information indicating a change in serving cell power level, wherein the indication indicates the change is in response to a change in backhaul link capacity and adapting an uplink transmit power based on the received indication. In some examples of this aspect the power level comprises a reference signal power level. In some examples the reference signal power level is at least one of SSB/CSI-RS power and referenceSignalPower. In some examples the signalled information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level indicative to the wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level and the wireless device maintaining its uplink transmit power based on the received indication. In some examples the signalling information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the receiving of the information in a MAC CE or a DCI is the indication that the wireless device is to maintain its uplink transmission power with respect to the adapted serving cell power level. The received information may comprise a transmit power level parameter to indicate to reduce the transmit power of the wireless device. The received information may also comprise a cell uplink power control offset and the wireless adapting the uplink transmit power per sub-band calculation based on the cell uplink power control offset. The power per sub-band may be calculated according to:

In some examples of this aspect, the wireless device corresponds to a high data rate user. In further examples, the received information comprises a backhaul link identifier. In some examples the wireless device is an IAB node. In some examples the signalling information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI.

In another aspect, an integrated access and backhaul, IAB, node for adapting a serving cell capacity is provided. The IAB node is configured to determine a value corresponding to a backhaul link capacity, adapt, based on the determined value, a power level of the serving cell and signal, to one or more served wireless devices, information indicative of the adapted serving cell power level. In some examples the power level comprises a reference signal power level. In some examples the reference signal power level is at least one of SSB/CSI-RS power and referenceSignalPower. In some examples the signalled information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level indicative to the one or more wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level. In some examples the signalling information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the one or more wireless devices are determined to be within a predefined distance from the served cell and/or with a radio channel quality above a certain level. In other examples, the IAB node is further configured to send to one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices. The transmit power level parameter may be a cell uplink power control offset to be applied to a power per sub-band calculation to be performed by the one or more wireless devices, causing a per wireless device reduction in uplink transmit power. In some examples the transmit power level parameter is comprised in a MAC CE. In some examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI. In some examples the one or more wireless devices are determined to correspond to high data rate users. In some examples of this aspect the IAB node is further configured to determine a second value corresponding to the backhaul link capacity and send to a further one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices based on the determined second value corresponding to the backhaul link capacity. In some examples the signalled information and/or signalled transmit power level further comprises a backhaul link identifier. In some examples the wireless device is an IAB node.

In another aspect, a wireless device for communicating with an integrated access and backhaul, IAB, node, is provided. The wireless device is configured to receive information indicating a change in serving cell power level, wherein the indication indicates the change is in response to a change in backhaul link capacity and adapt an uplink transmit power based on the received indication. In some examples the power level comprises a reference signal power level. In some examples the reference signal power level is at least one of SSB/CSI-RS power and referenceSignalPower. In some examples the received information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level indicative to the wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level and the wireless device maintaining its uplink transmit power based on the received indication. In some examples the received information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the receiving of the information in a MAC CE or a DCI is the indication that the wireless device is to maintain its uplink transmission power with respect to the adapted serving cell power level. In some examples the received information comprises a transmit power level parameter to indicate to reduce the transmit power of the wireless device. In some examples the received information comprises a cell uplink power control offset and the wireless adapting the uplink transmit power per sub-band calculation based on the cell uplink power control offset. In some examples the power per sub-band is calculated according to:

In some examples the wireless device corresponds to a high data rate user. The received information may comprise a backhaul link identifier. In some examples the wireless device is an IAB node. In some examples the signalling information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI.

In another aspect a computer program is provided. The computer program comprising instructions which when executed on a processor, cause the processor to perform any one of the methods described above. A computer program product, memory or carrier may also be provided which comprises the aforementioned computer program.

DETAILED DESCRIPTION

Embodiments are disclosed to address one or more problems previously discussed, where some embodiments are exemplified with the aid of drawings whereas others, are contained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

For example, with reference toFIG.5, which depicts a further example of an IAB hierarchy. When an IAB does handover (migrating an IAB node) or a backhaul (BH) link quality drops below a threshold some UEs and other down-stream (child) IABs connected to this IAB node may declare radio link failure, this would cause a long service interruption. As RLF failure has to be notified to the UEs which then have to start the failure recovery procedure. The present disclosure considers solutions which avoid this situation, providing at least the advantage of reduced radio link failures.

FIG.6depicts how the backhaul capacity deteriorates to a level below the IAB node capacity. The method to adapt the IAB node's capacity to the backhaul current link capacity is as follows:

In one embodiment a first step is to lower the power on the synchronization signal physical broadcast channel (SSB)/CSI-RS and the referenceSignalPower which causes the cell border to decrease in size. This means that UEs' RSRP measurement will be decreased and since RSRP is typically used in mobility measurements, some cell edge UEs connected to the IAB node (and possible child IAB nodes) will make a handover to neighbouring nodes. The power is decreased until the necessary number of UEs has made a handover or until a minimum transmit power is reached.

The referenceSignalPower needs to be signaled to UEs which are not near the cell edge so that those UEs DL path loss estimate doesn't change relative to the previous SSB/CSI-RS and/or referenceSignalPower level although the monitored DL RSRP has decreased due to lower power on the SSB/CSI-RS. Those UEs will, as a result of the signalling indication, not increase their uplink transmission power via uplink power control. Since the backhaul link is degraded, this signaling is preferably not performed via the normal RRC which would need to be via the donor (and therefore using the BH capacity). Instead it is preferably performed for example, via medium access control (MAC) layer, e.g. a new MAC control element (CE) or downlink control information (DCI) based signalling. Compared to the existing signaling alternative (i.e., system information block (SIB) e.g. SIB1 or dedicated RRC signaling), the IAB node of the concerned BH link can signal in a fast manner to the relevant UEs (i.e., UEs determined not near to the cell edge) of change of the synchronization reference signals. Those UEs are then able to avoid increasing the UL transmission power although the measured RSRP has in reality decreased. The IAB node is able to determine UEs near to the cell border for example through positioning information (distance from the base station) or previously reported radio channel quality below a certain level or threshold.

In some examples, a second step could be performed, if the backhaul capacity is still lower than the IAB node capacity, where the transmit power of specific high data rate users is lowered. In some examples this is achieved by sending a cell-ulpc-offset to selected high data rate users, for example via MAC layer signalling (e.g. a new MAC-CE) which is applied, by the UE to the power per subband calculation in Equation. 2 above. In some examples this step may be repeated until the IAB node throughput is lower than the current BH capacity.

In other examples, the IAB node may send a DCI carrying a Transmit Power Control (TPC) command to selected UEs to adjust the transmission power for physical uplink shared channel (PUSCH). This method may be performed if the expected power adjustment is in a small range. If the expected power adjustment is large, the MAC CE based alternative would be faster in terms of latency.

As a result of one or more of the proposed embodiments, when a BH link radio quality becomes bad, which has a risk to cause BH RLF on the BH link of a path/route, the other hops (at least downstream links) of the path/route are adjusted accordingly to be aligned with the reduced BH link capacity. The adjustment ensures that a portion of the cell edge UEs can perform timely recovery actions (such as handover) and in some examples, if needed, high bit-rate UEs reduce their UL bitrate. At least one advantage with the latter is that by decreasing users UL bitrate, the cell adapts to the BH available capacity and lowers the interference in the IAB cell. These actions mean that the cell coverage is reduced in both the DL and the UL and can result in averting UEs from triggering a RLF. Further advantages are that an IAB node can take proper recovery actions for the BH RLF in good time to reduce latency while avoiding flooding other links with signaling distribution. With this approach a natural selection of targeting the cell edge users results without adversely affecting other UEs. By using direct signalling such as the proposed MAC CE and/or DCI based signaling, the IAB node of the concerned BH link can control the relevant UEs of change of the synchronization reference signals and/or the cell-ulpc-offset.in a fast manner, thus providing low latency/fast response to a detected BH capacity problem.

An example embodiment is depicted inFIG.7. The first step702is to obtain the BH capacity. The IAB node then at704compares the IAB throughput and the BH capacity. If the BH capacity can handle the wanted IAB node throughput (previously, for simplicity, also referred to as capacity, see for example,FIG.6), if it can the comparison at704results in no changes being required. Step702may be repeated periodically or may be triggered due to certain thresholds being met. If the BH cannot handle the wanted IAB node throughput, i.e. the BH capacity is lower than the IAB node capacity at step706, the IAB node decreases the SS/PBCH block and/or CSI-RS and the referenceSignalPower with x decibels (dB) in steps to force cell-edge users to make a handover to adjacent cells. The referenceSignalPower is signaled at step708via a new MAC-CE. It should be noted that by doing this only the RSRP measurements used in mobility are affected (decreased) and not the pathloss measurement used by the UL power control.

When the decrease of the SS/PBCH block and/or CSI-RS and the referenceSignalPower with x dB is performed, the IAB node wanted throughput is once again checked against the BH capacity and if necessary the SS/PBCH block and/or CSI-RS and the referenceSignalPower is decreased by x db again. Since the power cannot be decreased too much, there is a minimum transmit power, at step710the decrease x of the transmit power may be checked against a maximum value maxX dB and the process is only repeated if the power decrease is still within the allowed limit.

Another example embodiment is depicted inFIG.8. The IAB node throughput is compared with the BH capacity at step802. If the BH capacity is lower than the wanted IAB throughput, the IAB at step804finds high throughput users in the UL. In some examples the IAB determines the high throughput users as those with high buffer status report (BSR)/grant request. In other examples the high throughput users are determined based on a high amount of data buffered in the IAB node waiting to be sent on the BH link. The embodiment is not limited to these examples as many other means may be considered and provide the same advantageous effect. At step806the IAB node increments the Cell-ULPC-OFFSET and at step808the IAB transmits the value to the selected UEs. In some examples the Cell-ULPC-OFFSET is set to an initial value, for example 0. In some examples the signal is transmitted806as a MAC CE. This directs the selected UEs to decrease their UL transmit power. In some examples this is determined by the IAB at step810. The process may then repeat to step802. In some examples the repeat of the process is based on the determined UE Tx power. The Cell-ULPC-OFFSET is applied by the UE to the power per subband such as:

As mentioned above, the process may be repeated if the BH capacity is still lower than the IAB wanted throughput. The embodiment advantageously decreases a plurality of UEs requested throughput in an automated manner and also lowering the interference in the IAB cell due to the effective shrinking of the cell in both the DL and the UL.

One of more of the previously described embodiments proposes signaling referenceSignalPower and/or cell-ulpc-offset to selected wireless devices (UE or subordinate IAB node). According to the existing signaling alternatives in 3GPP, a gNB sends reference power level signaling to wireless devices through one or more of the following means:1) to a plurality of UEs via SIB1 in a cell broadcast fashion.2) to specific UEs via dedicated RRC signalling.

However, there are some drawbacks observed for the existing signaling alternatives. SIB1 is broadcast signalling which is transmitted at predefined time periods and is typically slow in comparison to a dedicated signalling method. Frequent transmission of SIB1 may lead to control signaling overhead and should thus be avoided. In addition, a UE in RRC connected mode would not read SIB1, which means that such a UE will not be able to receive the updated power information via SIB1. The reference power values are used by the UE to estimate its UL transmission power. Dedicated RRC signaling based alternatives have the problem that the RRC entities are terminated at the IAB donor and the UE. This means that the IAB donor is responsible for exchanging RRC signaling with the UE. For the proposed embodiments the IAB node of the concerned BH link would need to first inform the IAB donor of the relevant information before the donor can signal the UE via dedicated RRC. This would cause extra latency to the signalling and additional signalling load to the backhaul interfaces.

In some examples of the disclosed embodiments it is proposed that the IAB node signals the power level information via MAC layer (e.g. a MAC CE) or DCI based signalling.

In some examples this can be achieved using A MAC CE addressed to a UE-unique ID such as C-RNTI or a plurality of UEs through a group ID. In other examples a DCI may be used which is then also addressed to a UE unique ID such as C-RNTI or a plurality of UEs through a group ID.

For the MAC layer solution, a new MAC CE can be introduced to carry the ss-PBCH-BlockPower or powerControlOffsetSS.

In an example, as shown inFIG.9a, the new MAC CE may contain only 1 octet to carry the referenceSignalPower. In the example, the referenceSignalPower field occupies 1 octet. In other examples, the referenceSignalPower field may take different length. In the example, depending on whether the referenceSignalPower is provided by ss-PBCH-BlockPower or by powerControlOffsetSS, the MAC CE carries either the value of ss-PBCH-BlockPower or the value of powerControlOffsetSS. When the UE receives the MAC CE, the UE can correctly interpret the received information since the UE has already learned the information on this via reading SIB signalling. In other words, the SIB1 may indicate if the value in the MAC CE is ss-PBCH-BlockPower or powerControlOffsetSS.

In another example, the new MAC CE may contain two fields to carry both ss-PBCH-BlockPower and powerControlOffsetSS. In a similar manner as in other examples, the two fields may use different lengths. If so, some reserved “R” bits may be defined. In case both fields are present, in another example, both fields may be placed in different order, i.e., the first octet carries the value of powerControlOffsetSS, while the second octet carries the value of ss-PBCH-BlockPower. An example of the MAC CE is shown inFIG.9b.

In yet another example, indicators in the MAC subheader may be introduced to indicate whether ss-PBCH-BlockPower and/or powerControlOffsetSS is/are carried in the MAC CE. In this case, the UE may not need to read SIB signalling to obtain the setting of the reference signal power, i.e. whether the MAC CE carries either the value of ss-PBCH-BlockPower or the value of powerControlOffsetSS. It is enough for the UE to obtain the setting via the MAC CE. In any of the disclosed examples, a new LCID may be defined for the MAC CE.

For the DCI solution, in some examples one or two fields may be introduced in an existing DCI format (either UL DCI carrying UL grant or DL DCI carrying DL assignment, or group common DCI, or DCI carrying neither UL grant nor DL assignment). If the DCI contains a reserved “R” field, we can use some bits from the R field to carry the reference signal power. If there is no R field in the DCI signalling, the existing DCI format may be extended with new fields. In other examples, a new DCI format for signalling the reference signal power may be introduced.

In some examples, a UE may be connected with multiple BH links. The IAB donor may configure the UE with separate SS/PBCH blocks and/or separate CSI-RSs on the downlink stream access link, and each of which is associated with a separate BH link. For any single BH link, any above embodiment is equally applicable. Where a new MAC CE is defined for carrying the reference signal power, the new MAC CE may also carry a BH link index for each BH link. In an example shown inFIG.10, the new MAC CE can be defined so that it includes a referenceSignalPower octet for each BH link.

In another example as shown inFIG.11, a bitmap field may be defined to indicate the BH link indices. Each bit is associated with a specific BH link. In some examples each bit takes the value ‘1’ when indicating that the reference signal power is carried in the MAC CE for the corresponding BH link, while the bit takes the value ‘0’ meaning that the reference signal power is not carried in the MAC CE for the corresponding BH link. In other examples the bit value/meaning may be reversed. In the example ofFIG.11, the referenceSignalPower octets are included in sequence order associated with the BH links to which they are associated, and thus in the example only 3 backhaul links out of a possible 8 BH links. The skilled person will understand that other means to achieve the disclosed embodiment without deviating from the essential aspects disclosed herein. For example further information may be required to associate each BH link with the bit in the bitmap. In other examples, the fields may have different lengths.

The proposed protocol enhancements are equally applicable for the signaling of the cell-ulpc-offset for example. In addition, any one of the embodiments exemplified byFIGS.9to11may be combined in one or more combinations, for example to indicate both referenceSignalPower(SSB) and referenceSignalPower(OffsetSS) on a per BH link basis.

To determine when the IAB node needs to adjust its transit power and the UL transmit power, the following triggers may be used:The BH total throughput is lower than the total throughput of the IAB node. This may be measured as the sum of the throughput over all PRBs.The BH radio link quality threshold (in terms of metrics such as RSRP, RSRQ, RSSI, SINR, out-of-synch indications) is below a threshold.The BH latency is a threshold.The BH link is compared to a downstream link. If the BH link provides lower capacity than the downstream link, adjustment of the downstream link can be enabled.

The above triggers may be used alone or a combination of triggers or thresholds may be employed.

The above described embodiments may be implemented as methods performed by an IAB node, a wireless device such as a UE or a subordinate IAB node, i.e. an IAB child node. The above described embodiments may alternatively be implemented by apparatus configured to perform one or more functions comprising one or more of the disclosed embodiments. These methods and apparatus will now be described in more detail in conjunction with the figures.

InFIG.12, a method1200for adapting a serving cell capacity is performed by an integrated access and backhaul, IAB, node. The method begins with the IAB node determining1202a value corresponding to a backhaul link capacity. The IAB node then adapts1204a power level of the serving cell based on the determined value. The IAB node then signals1206to one or more served wireless devices information indicative of the adapted serving cell power level. In some examples of the method1200the power level comprises a reference signal power level. The reference signal power level may be at least one of SSB/CSI-RS power and referenceSignalPower. In some examples of the method1200the signalled information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level which indicates to the one or more wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level. In some examples of the method1200the signalling information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples of the method1200the one or more wireless devices are determined to be within a predefined distance from the served cell and/or with a radio channel quality above a certain level. In other words, the signalling information is not set to UEs determined to be “at the cell edge”, or greater than a certain distance from the serving cell/with a radio channel quality below a certain level or threshold. In some examples of the method1200, the method further comprises the IAB node sending to one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices. The transmit power level parameter may be a cell uplink power control offset to be applied to a power per sub-band calculation to be performed by the one or more wireless devices. The signalling of the power level parameter causing a per wireless device reduction in uplink transmit power. The transmit power level parameter may in some examples be comprised in a MAC CE. In other examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI. In some examples of the method1200when the IAB node sends the transmit power level parameter, the one or more wireless devices are first determined to correspond to high data rate users as described previously. In some examples of the method1200when the IAB node sends the transmit power level parameter the method further comprises the IAB node determining a second value corresponding to the backhaul link capacity and sending to a further one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices based on the determined second value corresponding to the backhaul link capacity. In other words, the IAB repeats the process. The signalling may be to the same wireless devices, a subset or the previously signalled wireless devices or a different one or more wireless devices. In some examples of the method1200, the signalled information and/or signalled transmit power level further comprises a backhaul link identifier. As previously described, this may be indicated in different ways through protocol enhancement or extension. In any of the above described examples of the method1200, the wireless device may be a UE or it may be another IAB node.

FIG.13is a method1300performed by a wireless device served by an integrated access and backhaul, IAB, node. The method begins with the wireless device receiving1302information indicating a change in serving cell power level, wherein the indication indicates the change is in response to a change in backhaul link capacity. The wireless device adapts1304an uplink transmit power based on the received indication. In some examples the power level comprises a reference signal power level. In some examples the reference signal power level is at least one of SSB/CSI-RS power and referenceSignalPower. In some examples the signalled information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level indicative to the wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level and the wireless device maintaining its uplink transmit power based on the received indication. In some examples the received information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples, the receiving of the information in a MAC CE or a DCI is the indication that the wireless device is to maintain its uplink transmission power with respect to the adapted serving cell power level. In some examples the received information comprises a transmit power level parameter to indicate to reduce the transmit power of the wireless device. The received information may comprise a cell uplink power control offset and the wireless adapting the uplink transmit power per sub-band calculation based on the cell uplink power control offset. In some examples the power per sub-band is calculated according to:

wherein P0=alfa*(sinrTarget+lin2db(noisePowerPerSubband)+noiseRise)+(1−alfa)*(maximumPower−lin2db(M0))
parameter a is the fractional pathloss compensation factor where 1.0 means total compensation;PL is the downlink path loss; andM0=the default number of sub-bands or resource blocks.

In some examples of the method1300, when the received information comprises a transmit power level parameter to indicate to reduce the transmit power of the wireless device the wireless device corresponds to a high data rate user. In some examples of the method1300the received information comprises a backhaul link identifier. In any of the examples of the method1300the wireless device may be a UE or it may be another IAB node, i.e a subordinate IAB node or child IAB node. As previously described the received information comprising a transmit power level parameter to indicate to reduce the transmit power of the wireless device may also be comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI.

FIG.14illustrates and example IAB node200. The IAB node may comprise a number of logical functional units, for example processing circuitry210, memory220comprising a computer program230, transceiver circuitry240for transmitting and receiving signals for example to/from a parent IAB node, a child IAB node and/or wireless devices, mobile termination (MT)250and distribution unit (DU)260.

In some embodiments the processing circuitry210is configured to determine a value corresponding to a backhaul link capacity. The processing circuitry210is further configured to adapt a power level of the serving cell based on the determined value. The processing circuitry210is further configured to signal via the transceiver circuitry240to one or more served wireless devices information indicative of the adapted serving cell power level. In some examples the power level comprises a reference signal power level. The reference signal power level may be at least one of SSB/CSI-RS power and referenceSignalPower. In some examples the signalled information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level which indicates to the one or more wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level. In some examples the signalling information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the one or more wireless devices are determined to be within a predefined distance from the served cell and/or with a radio channel quality above a certain level. In other words, the signalling information is not set to UEs determined to be “at the cell edge”, or greater than a certain distance from the serving cell/with a radio channel quality below a certain level or threshold. In some examples the processing circuitry210is further configured to signal via the transceiver circuitry240to one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices. The transmit power level parameter may be a cell uplink power control offset to be applied to a power per sub-band calculation to be performed by the one or more wireless devices. The signalling of the power level parameter causing a per wireless device reduction in uplink transmit power. The transmit power level parameter may in some examples be comprised in a MAC CE. In other examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI. In some examples when the IAB node sends the transmit power level parameter, the one or more wireless devices are first determined to correspond to high data rate users as described previously. In some examples when the IAB node sends the transmit power level parameter the processing circuitry is further configured to determine a second value corresponding to the backhaul link capacity and to send via the transceiver circuitry240to a further one or more wireless devices a transmit power level parameter to reduce the transmit power of the one or more wireless devices based on the determined second value corresponding to the backhaul link capacity. In other words, the IAB repeats the process. The signalling may be to the same wireless devices, a subset or the previously signalled wireless devices or a different one or more wireless devices. In some examples the signalled information and/or signalled transmit power level further comprises a backhaul link identifier. As previously described, this may be indicated in different ways through protocol enhancement or extension. In any of the above described examples the wireless device may be a UE or it may be another IAB node.

FIG.15illustrates an example wireless device300. The wireless device300may comprise a number of logical functional units, for example processing circuitry310, memory320comprising a computer program330, transceiver circuitry340for transmitting and receiving signals for example to/from the serving IAB node.

In some embodiments the processing circuitry310is configured to receive, via the transceiver circuitry340information indicating a change in serving cell power level, wherein the indication indicates the change is in response to a change in backhaul link capacity. The processing circuitry310is configured to adapt an uplink transmit power based on the received indication. In some examples the power level comprises a reference signal power level. In some examples the reference signal power level is at least one of SSB/CSI-RS power and referenceSignalPower. In some examples the received information comprises a reference signal power parameter to indicate an adapted path loss level corresponding to the adapted serving cell power level indicative to the wireless device to maintain its uplink transmission power with respect to the adapted serving cell power level and the processing circuitry310is configured to maintain its uplink transmit power based on the received indication. In some examples the received information is comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples, the receiving of the information in a MAC CE or a DCI is the indication that the wireless device is to maintain its uplink transmission power with respect to the adapted serving cell power level. In some examples the received information comprises a transmit power level parameter to indicate to reduce the transmit power of the wireless device. The received information may comprise a cell uplink power control offset and the wireless adapting the uplink transmit power per sub-band calculation based on the cell uplink power control offset. In some examples the power per sub-band is calculated according to:

In some examples when the received information comprises a transmit power level parameter to indicate to reduce the transmit power of the wireless device the wireless device corresponds to a high data rate user. In some examples the received information comprises a backhaul link identifier. In any of the examples the wireless device300may be a UE or it may be another IAB node, i.e a subordinate IAB node or child IAB node. As previously described the received information comprising a transmit power level parameter to indicate to reduce the transmit power of the wireless device may also be comprised in a medium access control, MAC, control element, CE, or in a downlink control information, DCI. In some examples the transmit power level parameter comprises a transmit power control, TPC, command in a DCI.

FIG.16is a block diagram illustrating an example IAB node400comprising software modules according to one or more embodiments of the present disclosure. The determining module410may be configured to perform one or more of the methods previously described for determining a value corresponding to a backhaul link capacity. The adapting module420may be configured to perform one or more of the methods previously described for a power level of the serving cell based on the determined value. The signaling module430may be configured to perform any one of the methods previously described for transmitting signaling, for example to signal to one or more served wireless devices information indicative of the adapted serving cell power level.

FIG.17is a block diagram illustrating an example wireless device500comprising software modules according to one or more embodiments of the present disclosure. Receiving module510may be configured to perform one or more of the methods previously described for receiving information indicating a change in serving cell power level, wherein the indication indicates the change is in response to a change in backhaul link capacity. Adapting module520may be configured to perform one or more of the methods previously described for adapting an uplink transmit power based on the received indication.

FIG.18depicts an example structure of an IAB node1900comprising MT1910and DU1960entities. The DU entities are depicted separated to highlight the independence of the functions. Although the subject matter described herein may be implemented in any appropriate type of system using any suitable components, the embodiments disclosed herein are described in relation to a wireless network, such as the example wireless network illustrated inFIG.19. In practice, a wireless network may further include any additional elements suitable to support communication between wireless devices or between a wireless device and another communication device, such as a landline telephone, a service provider, or any other network node or end device. Of the illustrated components, DU1960and MT1910are depicted with additional detail. It should be noted that these functions may be logically and/or physically separated or combined within an IAB node. The wireless network may provide communication and other types of services to one or more wireless devices to facilitate the wireless devices' access to and/or use of the services provided by, or via, the IAB node1900.

DU1960and MT1910comprise various components described in more detail below. These components work together in order to provide IAB node1900functionality, such as providing wireless connections in a wireless network. Specifically, the entities described in further detail below are suitable to provide one or more of the embodiments disclosed herein.

In different embodiments, the wireless network may comprise any number of wired or wireless networks, IAB nodes, other network nodes, base stations, controllers, wireless devices, relay stations, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections.

InFIG.18, DU1960includes processing circuitry1970, device readable medium1980, interface1990, auxiliary equipment1984, power source1986, power circuitry1987, and antenna1962. Although DU1960illustrated in the example wireless network ofFIG.19may represent a device that includes the illustrated combination of hardware components, other embodiments may comprise DUs with different combinations of components. It is to be understood that a DU comprises any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Moreover, while the components of DU1960are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, a DU may comprise multiple different physical components that make up a single illustrated component (e.g., device readable medium1980may comprise multiple separate hard drives as well as multiple RAM modules).

Similarly, DU1960may be composed of multiple physically separate components which may each have their own respective components. In some embodiments, DU1960may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate device readable medium1980for the different RATs) and some components may be reused (e.g., the same antenna1962may be shared by the RATs). DU1960may also include multiple sets of the various illustrated components for different wireless technologies integrated into DU1960, such as, for example, GSM, WCDMA, LTE, NR, WiFi, or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within DU1960.

Processing circuitry1970is configured to perform any determining, calculating, or similar operations (e.g., certain obtaining operations) described herein as being provided by a DU. These operations performed by processing circuitry1970may include processing information obtained by processing circuitry1970by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the DU, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination.

Processing circuitry1970may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other DU1960components, such as device readable medium1980, DU1960functionality. For example, processing circuitry1970may execute instructions stored in device readable medium1980or in memory within processing circuitry1970. Such functionality may include providing any of the various wireless features, functions, or benefits discussed herein. In some embodiments, processing circuitry1970may include a system on a chip (SOC).

In some embodiments, processing circuitry1970may include one or more of radio frequency (RF) transceiver circuitry1972and baseband processing circuitry1974. In some embodiments, radio frequency (RF) transceiver circuitry1972and baseband processing circuitry1974may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry1972and baseband processing circuitry1974may be on the same chip or set of chips, boards, or units.

In certain embodiments, some or all of the functionality described herein as being provided by an IAB node may be performed by processing circuitry1970executing instructions stored on device readable medium1980or memory within processing circuitry1970. In alternative embodiments, some or all of the functionality may be provided by processing circuitry1970without executing instructions stored on a separate or discrete device readable medium, such as in a hard-wired manner. In any of those embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry1970can be configured to perform the described functionality. The benefits provided by such functionality are not limited to processing circuitry1970alone or to other components of network node1960, but are enjoyed by network node1960as a whole, and/or by end users and the wireless network generally.

Device readable medium1980may comprise any form of volatile or non-volatile computer readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by processing circuitry1970. Device readable medium1980may store any suitable instructions, data or information, including a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry1970and, utilized by network node1960. Device readable medium1980may be used to store any calculations made by processing circuitry1970and/or any data received via interface1990. In some embodiments, processing circuitry1970and device readable medium1980may be considered to be integrated.

Interface1990is used in the wired or wireless communication of signalling and/or data between the IAB node and other network nodes. As illustrated, interface1990comprises port(s)/terminal(s)1994to send and receive data, for example to and from network1906over a wired connection. Interface1990also includes radio front end circuitry1992that may be coupled to, or in certain embodiments a part of, antenna1962. Radio front end circuitry1992comprises filters1998and amplifiers1996. Radio front end circuitry1992may be connected to antenna1962and processing circuitry1970. Radio front end circuitry may be configured to condition signals communicated between antenna1962and processing circuitry1970. Radio front end circuitry1992may receive digital data that is to be sent out to other network nodes or wireless devices via a wireless connection. Radio front end circuitry1992may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters1998and/or amplifiers1996. The radio signal may then be transmitted via antenna1962. Similarly, when receiving data, antenna1962may collect radio signals which are then converted into digital data by radio front end circuitry1992. The digital data may be passed to processing circuitry1970. In other embodiments, the interface may comprise different components and/or different combinations of components.

In certain alternative embodiments, DU1960may not include separate radio front end circuitry1992, instead, processing circuitry1970may comprise radio front end circuitry and may be connected to antenna1962without separate radio front end circuitry1992. Similarly, in some embodiments, all or some of RF transceiver circuitry1972may be considered a part of interface1990. In still other embodiments, interface1990may include one or more ports or terminals1994, radio front end circuitry1992, and RF transceiver circuitry1972, as part of a radio unit (not shown), and interface1990may communicate with baseband processing circuitry1974, which is part of a digital unit (not shown).

Antenna1962may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. Antenna1962may be coupled to radio front end circuitry1990and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In some embodiments, antenna1962may comprise one or more omni-directional, sector or panel antennas operable to transmit/receive radio signals between, for example, 2 GHz and 66 GHz. An omni-directional antenna may be used to transmit/receive radio signals in any direction, a sector antenna may be used to transmit/receive radio signals from devices within a particular area, and a panel antenna may be a line of sight antenna used to transmit/receive radio signals in a relatively straight line. In some instances, the use of more than one antenna may be referred to as MIMO. In certain embodiments, antenna1962may be separate from DU1960and may be connectable to DU1960through an interface or port.

Antenna1962, interface1990, and/or processing circuitry1970may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by an IAB node. Any information, data and/or signals may be received from a wireless device, another IAB node or network node and/or any other network equipment. Similarly, antenna1962, interface1990, and/or processing circuitry1970may be configured to perform any transmitting operations described herein as being performed by an IAB node. Any information, data and/or signals may be transmitted to a wireless device, another IAB node or other network node and/or any other network equipment.

Power circuitry1987may comprise, or be coupled to, power management circuitry and is configured to supply the components of DU1960with power for performing the functionality described herein. Power circuitry1987may receive power from power source1986. Power source1986and/or power circuitry1987may be configured to provide power to the various components of DU1960in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). Power source1986may either be included in, or external to, power circuitry1987and/or DU1960. For example, DU1960may be connectable to an external power source (e.g., an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry1987. As a further example, power source1986may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry1987. The battery may provide backup power should the external power source fail. Other types of power sources, such as photovoltaic devices, may also be used.

Alternative embodiments of IAB node may include additional components beyond those shown inFIG.19that may be responsible for providing certain aspects of the IAB node's functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, IAB node may include user interface equipment to allow input of information into the IAB node and to allow output of information from IAB node. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions.

As illustrated, MT1910may include antenna1911, interface1914, processing circuitry1920, device readable medium1930, user interface equipment1932, auxiliary equipment1934, power source1936and power circuitry1937. MT1910may include multiple sets of one or more of the illustrated components for different wireless technologies supported by MT1910, such as, for example, GSM, WCDMA, LTE, NR, WiFi, WiMAX, or Bluetooth wireless technologies, just to mention a few. These wireless technologies may be integrated into the same or different chips or set of chips as other components within MT1910.

Antenna1911may include one or more antennas or antenna arrays, configured to send and/or receive wireless signals, and is connected to interface1914. In certain alternative embodiments, antenna1911may be separate from MT1910and be connectable to MT1910through an interface or port. Antenna1911, interface1914, and/or processing circuitry1920may be configured to perform any receiving or transmitting operations described herein as being performed by a DU. Any information, data and/or signals may be received from a network node and/or another DU. In some embodiments, radio front end circuitry and/or antenna1911may be considered an interface.

As illustrated, interface1914comprises radio front end circuitry1912and antenna1911. Radio front end circuitry1912comprise one or more filters1918and amplifiers1916. Radio front end circuitry1914is connected to antenna1911and processing circuitry1920, and is configured to condition signals communicated between antenna1911and processing circuitry1920. Radio front end circuitry1912may be coupled to or a part of antenna1911. In some embodiments, MT1910may not include separate radio front end circuitry1912; rather, processing circuitry1920may comprise radio front end circuitry and may be connected to antenna1911. Similarly, in some embodiments, some or all of RF transceiver circuitry1922may be considered a part of interface1914. Radio front end circuitry1912may receive digital data that is to be sent out to other network nodes or DUs via a wireless connection. Radio front end circuitry1912may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters1918and/or amplifiers1916. The radio signal may then be transmitted via antenna1911. Similarly, when receiving data, antenna1911may collect radio signals which are then converted into digital data by radio front end circuitry1912. The digital data may be passed to processing circuitry1920. In other embodiments, the interface may comprise different components and/or different combinations of components.

Processing circuitry1920may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and/or encoded logic operable to provide, either alone or in conjunction with other MT1910components, such as device readable medium1930, MT1910functionality. Such functionality may include providing any of the various wireless features or benefits discussed herein. For example, processing circuitry1920may execute instructions stored in device readable medium1930or in memory within processing circuitry1920to provide the functionality disclosed herein.

As illustrated, processing circuitry1920includes one or more of RF transceiver circuitry1922, baseband processing circuitry1924, and application processing circuitry1926. In other embodiments, the processing circuitry may comprise different components and/or different combinations of components. In certain embodiments processing circuitry1920of MT1910may comprise a SOC. In some embodiments, RF transceiver circuitry1922, baseband processing circuitry1924, and application processing circuitry1926may be on separate chips or sets of chips. In alternative embodiments, part or all of baseband processing circuitry1924and application processing circuitry1926may be combined into one chip or set of chips, and RF transceiver circuitry1922may be on a separate chip or set of chips. In still alternative embodiments, part or all of RF transceiver circuitry1922and baseband processing circuitry1924may be on the same chip or set of chips, and application processing circuitry1926may be on a separate chip or set of chips. In yet other alternative embodiments, part or all of RF transceiver circuitry1922, baseband processing circuitry1924, and application processing circuitry1926may be combined in the same chip or set of chips. In some embodiments, RF transceiver circuitry1922may be a part of interface1914. RF transceiver circuitry1922may condition RF signals for processing circuitry1920.

In certain embodiments, some or all of the functionality described herein as being performed by a DU may be provided by processing circuitry1920executing instructions stored on device readable medium1930, which in certain embodiments may be a computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by processing circuitry1920without executing instructions stored on a separate or discrete device readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry1920can be configured to perform the described functionality.

Processing circuitry1920may be configured to perform any determining, calculating, or similar operations (e.g., certain obtaining operations) described herein as being performed by the IAB node. These operations, as performed by processing circuitry1920, may include processing information obtained by processing circuitry1920by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored by MT1910, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination.

Device readable medium1930may be operable to store a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry1920. Device readable medium1930may include computer memory (e.g., Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (e.g., a hard disk), removable storage media (e.g., a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer executable memory devices that store information, data, and/or instructions that may be used by processing circuitry1920. In some embodiments, processing circuitry1920and device readable medium1930may be considered to be integrated.

User interface equipment1932may provide components that allow for a human user to interact with the IAB node. Such interaction may be of many forms, such as visual, audial, tactile, etc. User interface equipment1932may be operable to produce output to the user and to allow the user to provide input to the IAB node.

Power source1936may, in some embodiments, be in the form of a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic devices or power cells, may also be used. MT1910may further comprise power circuitry1937for delivering power from power source1936to the various parts of MT1910which need power from power source1936to carry out any functionality described or indicated herein. Power circuitry1937may in certain embodiments comprise power management circuitry. Power circuitry1937may additionally or alternatively be operable to receive power from an external power source; in which case MT1910may be connectable to the external power source (such as an electricity outlet) via input circuitry or an interface such as an electrical power cable. Power circuitry1937may also in certain embodiments be operable to deliver power from an external power source to power source1936. This may be, for example, for the charging of power source1936. Power circuitry1937may perform any formatting, converting, or other modification to the power from power source1936to make the power suitable for the respective components of MT1910to which power is supplied.

With reference toFIG.19, in accordance with an embodiment, a communication system includes a telecommunication network610, such as a 3GPP-type cellular network, which comprises an access network611, such as a radio access network, and a core network614. The access network611comprises a plurality of network nodes or base stations612a,612b,612c,such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area613a,613b,613c.Each network node or base station612a,612b,612cis connectable to the core network614over a wired or wireless connection615. A first wireless device691located in coverage area613cis configured to wirelessly connect to, or be paged by, the corresponding base station612c.A second wireless device692in coverage area613ais wirelessly connectable to the corresponding base station612a.While a plurality of wireless devices691,692are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole wireless device is in the coverage area or where a sole wireless device is connecting to the corresponding base station612.

The telecommunication network610is itself connected to a host computer630, which may be embodied in the hardware and/or software of a standalone server, a cloud- implemented server, a distributed server or as processing resources in a server farm. The host computer630may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections621,622between the telecommunication network610and the host computer630may extend directly from the core network614to the host computer630or may go via an optional intermediate network620. The intermediate network620may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network620, if any, may be a backbone network or the Internet; in particular, the intermediate network620may comprise two or more sub-networks (not shown).

The communication system ofFIG.19as a whole enables connectivity between one of the connected wireless devices691,692and the host computer630. The connectivity may be described as an over-the-top (OTT) connection650. The host computer630and the connected UEs691,692are configured to communicate data and/or signaling via the OTT connection650, using the access network611, the core network614, any intermediate network620and possible further infrastructure (not shown) as intermediaries. The OTT connection650may be transparent in the sense that the participating communication devices through which the OTT connection650passes are unaware of routing of uplink and downlink communications. For example, a base station612may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer630to be forwarded (e.g., handed over) to a connected UE691. Similarly, the base station612need not be aware of the future routing of an outgoing uplink communication originating from the UE691towards the host computer630.

Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference toFIG.20. In a communication system700, a host computer710comprises hardware715including a communication interface716configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system700. The host computer710further comprises processing circuitry718, which may have storage and/or processing capabilities. In particular, the processing circuitry718may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer710further comprises software711, which is stored in or accessible by the host computer710and executable by the processing circuitry718. The software711includes a host application712. The host application712may be operable to provide a service to a remote user, such as a UE730connecting via an OTT connection750terminating at the UE730and the host computer710. In providing the service to the remote user, the host application712may provide user data which is transmitted using the OTT connection750.

The communication system700further includes a base station720provided in a telecommunication system and comprising hardware725enabling it to communicate with the host computer710and with the UE730. The hardware725may include a communication interface726for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system700, as well as a radio interface727for setting up and maintaining at least a wireless connection770with a UE730located in a coverage area (not shown inFIG.7) served by the base station720. The communication interface726may be configured to facilitate a connection760to the host computer710. The connection760may be direct or it may pass through a core network (not shown inFIG.21) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware725of the base station720further includes processing circuitry728, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station720further has software721stored internally or accessible via an external connection.

The communication system700further includes the UE730already referred to. Its hardware735may include a radio interface737configured to set up and maintain a wireless connection770with a base station serving a coverage area in which the UE730is currently located. The hardware735of the UE730further includes processing circuitry738, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE730further comprises software731, which is stored in or accessible by the UE730and executable by the processing circuitry738. The software731includes a client application732. The client application732may be operable to provide a service to a human or non-human user via the UE730, with the support of the host computer710. In the host computer710, an executing host application712may communicate with the executing client application732via the OTT connection750terminating at the UE730and the host computer710. In providing the service to the user, the client application732may receive request data from the host application712and provide user data in response to the request data. The OTT connection750may transfer both the request data and the user data. The client application732may interact with the user to generate the user data that it provides.

It is noted that the host computer710, base station720and UE730illustrated inFIG.21may be identical to the host computer630, one of the base stations612a,612b,612cand one of the UEs691,692ofFIG.20, respectively. This is to say, the inner workings of these entities may be as shown inFIG.21and independently, the surrounding network topology may be that ofFIG.20.

InFIG.20, the OTT connection750has been drawn abstractly to illustrate the communication between the host computer710and the use equipment730via the base station720, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the UE730or from the service provider operating the host computer710, or both. While the OTT connection750is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

The wireless connection770between the UE730and the base station720is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE730using the OTT connection750, in which the wireless connection770forms the last segment. More precisely, the teachings of these embodiments may improve the radio network cell load and reliability enabling UEs accessing OTT services to maintain their connection and avoid performing handovers which could risk loss of connectivity.

A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection750between the host computer710and UE730, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection750may be implemented in the software711of the host computer710or in the software731of the UE730, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection750passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software711,731may compute or estimate the monitored quantities. The reconfiguring of the OTT connection750may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station720, and it may be unknown or imperceptible to the base station720. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer's710measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software711,731causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection750while it monitors propagation times, errors etc.

FIG.22is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a wireless device or UE which may be those described with reference toFIGS.19and20. For simplicity of the present disclosure, only drawing references toFIG.22will be included in this section. In a first step910of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In a second step920, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step930, the UE receives the user data carried in the transmission.

FIG.23is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a wireless device or UE which may be those described with reference toFIGS.19and20. For simplicity of the present disclosure, only drawing references toFIG.23will be included in this section. In an optional first step1010of the method, the UE receives input data provided by the host computer. Additionally or alternatively, in an optional second step1020, the UE provides user data. In an optional substep1021of the second step1020, the UE provides the user data by executing a client application. In a further optional substep1011of the first step1010, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in an optional third substep1030, transmission of the user data to the host computer. In a fourth step1040of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure.

FIG.24is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a wireless device or UE which may be those described with reference toFIGS.19and20. For simplicity of the present disclosure, only drawing references toFIG.24will be included in this section. In an optional first step1110of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In an optional second step1120, the base station initiates transmission of the received user data to the host computer. In a third step1130, the host computer receives the user data carried in the transmission initiated by the base station.

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