CN110115063B - Network apparatus and method for handover - Google Patents

Abstract

The present invention provides a network apparatus 100 and method 200 for deciding to Handover (HO) a User Equipment (UE)101 from a serving Base Station (BS)101 to a target base station 103. In particular, the network apparatus 100 is configured to obtain Full Duplex (FD) capability information of each neighboring base station 104 of the serving base station 102. Then, the network apparatus 100 is configured to request and receive Uplink (UL) channel quality measurements for the user equipment 101 from all or a subset of the above neighboring base stations, and is configured to determine one neighboring base station 104 as the target base station 103 based on the obtained full-duplex capability information and the received uplink channel quality measurements.

Description

Network apparatus and method for handover

Technical Field

The present invention relates to a network apparatus and method for Handing Over (HO) a User Equipment (UE) from a serving Base Station (BS) to a target BS. In particular, the network apparatus is used for making decisions on handover of the UE and may therefore also be referred to as HO decision entity.

Background

In wireless networks, mobility management is a key feature to ensure that end users are provided with ubiquitous quality of service in mobility scenarios. Indeed, in the case of mobility, particularly when a user needs to change from one coverage area to another, the user association requires HO procedures to avoid connection loss.

Fig. 13 summarizes conventional HO procedures and in particular shows that HO decisions (especially the determination of the target BS) are based on certain measurement reports sent by the UE in a mobility scenario (as specified by the third generation partnership project 3GPP standard; Technical Specification Group Radio Access Network; Automatic neighbor discovery Release (ANR) for UTRAN; Stage 2(Release 10)3GPP TS 25.484V10.0.0 (2011-06)).

According to the 3GPP standard, the only available HO-related information currently associated at the serving BS with its neighbor BSs (i.e., possible target BSs) includes a physical cell ID and Downlink (DL) channel information.

Currently, the serving BS does not have any other information about the possible target BSs. Specifically, the serving BS does not know whether the potential target BS has Full Duplex (FD) capability or Half Duplex (HD) capability. Further, in the HO procedure, the serving BS does not use and cannot currently use Uplink (UL) signal information (e.g., UL signal strength).

However, especially given the increasing importance of FD features in wireless networks, especially in 5G networks (FD features allow transmission and reception at the same time and same frequency band, i.e. in-band full duplex), such currently unavailable information would be very important for HO decisions.

This is because the BS perceived by the UE as being best in terms of signal quality may not be the best BS from a throughput perspective for a number of reasons (e.g., FD/HD capabilities of the BS). Currently, this fact is not considered in Radio Access Technology (RAT).

Fig. 14-16 illustrate the effect of these parameters on user performance. For example, in the network example shown in fig. 14, BS3 is better at receiving signal power (see right side of fig. 14), but BS4 provides acceptable coverage and the advantages of FD (see left side of fig. 14). Therefore, due to FD capability, BS4 may be a better choice for the mobile user after handover from BS2, i.e., a better choice for the target BS.

Based on these considerations, the inventors conducted advanced simulations. The simulation takes into account FD properties, in particular residual self-interference and inter-user interference (see schematic diagram of fig. 15). In fact, FD mode causes self-interference and inter-user interference, which will affect performance and should be expected in HO procedures. The impact of these two types of interference on throughput performance can only be measured using UL signals. However, as described above, current networks support only DL measurements for HO procedures.

As shown in fig. 15, self-interference affects the signal to noise ratio (SINR) of the UL signal of the UE 1. Measuring this UL SINR requires UL signaling from UE 1. The inter-user interference also affects the SINR of the DL signal of the UE 2. Measuring this DL SINR also requires UL signaling from UE 1.

For fig. 16, a scenario including one HD BS and one FD BS is considered. The focus here is on the UE in the HO procedure, where the measured SINR of the FD BS is lower than the SINR level of the HD BS, i.e. the UE is in the HO procedure

SINR_FD<SINR_HD

Following the conventional HO procedure, the UE will associate to the HD BS based on the HD BS's high level measured SINR. However, the conventional flow ignores the fact that: even with a greater SINR for HD BSs, FD BSs may provide greater throughput than HD BSs. This behavior was analyzed in more detail according to the simulation shown in fig. 16, where the user throughput after HO is shown for two cases: (1) the user performs a handover to the HD BS, and (2) the user performs a handover to the FD BS. Simulation assumptions and parameters are as follows:

based on fig. 16, it can be derived that: if the user switches to the BS that provides the optimal SINR, it will always be connected to the HD BS. As shown, the HD BS may not provide the highest throughput after the HO is completed. Thus, parameters like bandwidth, self-interference, and inter-user interference have a large impact on per-user throughput, and these parameters are completely ignored in the conventional HO procedure.

Currently, there is no specific mobility management method designed for the BS of the FD network or the hybrid FD/HD deployment in practice.

Disclosure of Invention

In view of the above problems and disadvantages, the present invention is directed to improving a conventional Handover (HO) procedure. It is an object of the present invention, inter alia, to provide a network apparatus and method that is capable of performing an enhanced HO procedure, i.e. a more efficient HO procedure that benefits from network elements (e.g. BS and UE) and Full Duplex (FD) mode of UL channel measurements. To this end, the present invention seeks to acquire additional information about FD capabilities of a BS, in particular of neighbor BSs of a serving BS serving a UE in a mobility scenario. Furthermore, the present invention is directed to acquiring additional information on UL channel quality between a UE and a neighbor BS of its serving BS.

The object of the invention is achieved by the solution provided in the appended independent claims. Advantageous embodiments of the invention are further defined in the dependent claims.

In short, the present invention proposes to acquire information on FD capabilities of neighbor BSs of a serving BS. In the conventional HO procedure, it is not known whether the neighbor BS is FD or HD. Therefore, the selection of target BSs for mobile UEs is based only on reported UE measurements and is completely independent of the FD/HD capabilities of these BSs. Furthermore, the present invention proposes to trigger measurement of UL channel quality between the UE and the neighbor BS in a mobility scenario. In a conventional HO procedure, the UE periodically measures DL channel quality from its serving BS and from neighbor BSs included in a list defined by an Automatic Neighbor Relation (ANR) function specified in 3GPP standard TS 25.484. The UE then reports these DL measurements to its serving BS when the predefined conditions are verified. Currently, UL channel quality measurements of neighbor BSs of the serving BS are neither performed nor available.

A first aspect of the present invention provides a network apparatus for deciding handover of a UE from a serving BS to a target BS, the network apparatus being configured to obtain FD capability information of each neighbor BS of the serving BS, request and receive UL channel quality measurements for the UE from all or a subset of the neighbor BSs, and determine one neighbor BS as the target BS based on the obtained FD capability information and the received UL channel quality measurements.

By obtaining additional FD capability information and UL channel quality measurements for all or a subset of the above-mentioned neighbor BSs (with FD and/or HD capabilities), the network apparatus may take enhanced HO decisions, especially ones that take into account FD capabilities of different network entities. That is, better decisions can be made overall, which can benefit from FD capabilities in future networks. Enhanced HO decisions significantly improve overall network performance, in particular, improve UE performance after completion of HO operations. Enhanced HO decisions also reduce the number of HO failures.

UL channel quality measurements may advantageously be requested and received from each FD-capable neighbor BS of the serving BS. That is, one possible subset of the above-described neighbor BSs may include all FD-capable neighbor BSs. However, UL measurements may also be requested from, performed on, and then received from the HD neighbor BSs and may be considered in the HO decision. That is, another possible subset of the neighbor BSs described above may also include all HD-capable neighbor BSs. The latter approach may also provide enhanced HO decisions with information about the measured UL quality. Of course, UL channel quality measurements may also be obtained from each FD/HD capable neighbor BS.

In a first implementation form of the network apparatus according to the first aspect, the network apparatus is configured to extract the FD capability information from a Neighbor Relation Table (NRT) available to at least the serving BS.

For example, the NRT may be updated periodically from the network side (e.g., Radio Network Controller (RNC)). Integrating the information into the NRT provides an efficient solution, which does not require any additional signaling between BSs or between a BS and a UE.

In a second implementation form of the network apparatus according to the first implementation form of the first aspect, the NRT comprises a field specifying the FD capabilities of each neighbor BS of the serving BS.

In a third implementation form of the network apparatus according to the first or second implementation form of the first aspect, the NRT comprises a field specifying a bandwidth supported by each neighbor BS of the serving BS.

Thereby, further useful information is provided to the network device, allowing the network device to make HO decisions that are superior, in particular in terms of throughput. Other useful information that may additionally or alternatively be included in the field of the NRT, for example, may be the mean of inter-user interference at FD capable neighbor BSs.

In a fourth implementation form of the network apparatus according to the first aspect, the network apparatus is configured to obtain the FD capability information through signaling interaction with each neighbor BS.

Accordingly, the network device can obtain the FD capability information without changing the conventionally used NRT design.

In a fifth implementation form of the network apparatus according to the fourth implementation form of the first aspect, the signaling interaction is performed over a backhaul connection, e.g. an X2 interface.

Thus, existing connections can be used without adding further complexity to the system.

In a sixth implementation form of the network apparatus according to the first aspect as such or according to any of the preceding implementation forms of the first aspect, the network apparatus is configured to provide an identity of the UE to each of the aforementioned neighbor BSs for triggering UL channel quality measurements between the respective aforementioned neighbor BSs and the UE.

In a seventh implementation form of the network apparatus according to the first aspect as such or according to any of the preceding implementation forms of the first aspect, the network apparatus is configured to receive, from the UE, DL channel quality measurements for all or a subset of the aforementioned neighbor BSs of the serving BS, and to determine the target BS further taking into account the DL channel quality measurements.

In other words, the network apparatus may make HO decisions based at least on the combined DL and UL channel quality measurements and FD capability information of all or a subset of the above-mentioned neighbor BSs (with FD and/or HD capabilities). Thus greatly improving HO decisions. The network device may also consider other information such as user status, supported bandwidth, etc. All information may be correlated with each other and may be weighted independently as desired.

In an eighth implementation form of the network apparatus according to the first aspect as such or according to any of the preceding implementation forms of the first aspect, the network apparatus is configured to obtain the FD capability information from the UE, and to determine the target BS further taking into account the FD capability information of the UE.

In particular, depending on whether the UE is FD capable, the network apparatus may take HO decisions in favor of SINR or throughput.

In a ninth implementation form of the network apparatus according to the first aspect as such or according to any of the preceding implementation forms of the first aspect, the network apparatus is or is comprised in or associated with a serving BS.

By including the network apparatus in at least one BS, a plurality of BSs or each BS in the network may become capable of an enhanced HO procedure. The network device may also be a stand-alone entity with which the network or BS is upgraded. The network apparatus may also be associated with multiple BSs.

In a tenth implementation form of the network apparatus according to the first aspect as such or according to any of the preceding implementation forms of the first aspect, the network apparatus is distributed over a serving BS and its neighbor BSs, wherein the serving BS is configured to obtain FD capability information, request UL channel quality measurements from all or a subset of the neighbor BSs, and determine and inform a potential target BS based on the obtained FD capability information, and the potential target BS is configured to determine whether it is a target BS for handover of the UE based on its FD capability and its UL channel quality measurements for the UE.

Thus, a distributed approach is achieved, wherein also the processing load is shared.

A second aspect of the present invention provides a method for handing over a UE from a serving BS to a target BS, the method comprising: the method includes obtaining FD capability information of each neighbor BS of a serving BS, requesting and receiving UL channel quality measurements for a UE from all or a subset of the neighbor BSs, and determining one neighbor BS as a target BS based on the obtained FD capability information and the received UL channel quality measurements.

In a first implementation form of the method according to the second aspect, the method comprises extracting FD capability information from a Neighbor Relation Table (NRT) available to at least the serving BS.

In a second implementation form of the method according to the first implementation form of the second aspect, the NRT comprises a field specifying the FD capabilities of each neighbor BS of the serving BS.

In a third implementation form of the method according to the first or second implementation form of the second aspect, the NRT comprises a field specifying a bandwidth supported by each neighbor BS of the serving BS.

In a fourth implementation form of the method according to the second aspect, the method comprises obtaining the FD capability information through signaling interaction with each neighbor BS as described above.

In a fifth implementation form of the method according to the fourth implementation form of the second aspect, the signaling interaction is performed over a backhaul connection, e.g. an X2 interface.

In a sixth implementation form of the method according to the second aspect as such or according to any of the preceding implementation forms of the second aspect, the method comprises providing to each of the aforementioned neighbor BSs an identity of the UE to trigger UL channel quality measurements between the respective aforementioned neighbor BSs and the UE.

In a seventh implementation form of the method according to the second aspect as such or according to any of the preceding implementation forms of the second aspect, the method comprises receiving DL channel quality measurements from the UE for all or a subset of the above-mentioned neighbor BSs of the serving BS, and determining the target BS further taking into account the DL channel quality measurements.

In an eighth implementation form of the method according to the second aspect as such or according to any of the preceding implementation forms of the second aspect, the method comprises obtaining FD capability information from the UE, and determining the target BS further taking into account the FD capability information of the UE.

In a ninth implementation form of the method according to the second aspect as such or according to any of the preceding implementation forms of the second aspect, the method is performed in the serving BS or the method is performed in association with the serving BS.

In a tenth implementation form of the method according to the second aspect as such or according to any of the preceding implementation forms of the second aspect, the method is performed distributively over the serving BS and its neighbor BSs, wherein the serving BS obtains FD capability information, requests UL channel quality measurements from all or a subset of the above neighbor BSs, and determines and informs a potential target BS based on the obtained FD capability information, and the potential target BS determines whether it is a target BS for handover of the UE based on its FD capability and its UL channel quality measurements for the UE.

With the method of the second aspect all the advantages of the network device of the first aspect may be achieved.

It has to be noted that all devices, elements, units and means described in the present application may be implemented as software elements or hardware elements or any type of combination thereof. All steps performed by the various entities described in the present application, as well as the functions described as being performed by the various entities, are intended to mean that the respective entities are adapted or used to perform the respective steps and functions. Even if in the following description of specific embodiments the specific functions or steps to be performed by an external entity are not reflected in the description of specific detailed elements of the entity performing the specific steps or functions, it should be clear to a person skilled in the art that these methods and functions can be implemented in individual software or hardware elements or any type of combination thereof.

Drawings

The above aspects and implementations of the invention are explained in the following description of specific embodiments in conjunction with the drawings, in which:

fig. 1 shows a network device according to an embodiment of the invention.

Fig. 2 shows a network device according to an embodiment of the invention for performing a method according to an embodiment of the invention.

Fig. 3 illustrates the general principle of the invention.

Fig. 4 illustrates a Neighbor Relation Table (NRT) used in a network apparatus according to an embodiment of the present invention.

Fig. 5 illustrates signaling interactions used by a network device in accordance with an embodiment of the present invention.

Fig. 6 shows a flow followed by a network device according to an embodiment of the invention.

Fig. 7 shows a schematic diagram of a network device according to an embodiment of the invention.

Fig. 8 shows signalling used in a method according to an embodiment of the invention.

Fig. 9 shows a centralized implementation of a network device according to an embodiment of the invention.

Fig. 10 illustrates a distributed implementation of a network device according to an embodiment of the invention.

Figure 11 shows the ANR induced interaction between RNC and O & M according to the 3GPP standard TS 25.484.

Figure 12 illustrates ANR report forwarding according to 3GPP standard TS 25.484.

Fig. 13 shows a conventional HO procedure.

Fig. 14 shows an example of a UE in a mobility scenario.

Fig. 15 shows interference factors sensed in the FD BS.

Fig. 16 shows a simulation of UE throughput as a function of number of users for FD BS and HD BS configurations.

Detailed Description

Fig. 1 shows a network device 100 according to a general embodiment of the invention. The network apparatus 100 is configured to decide to handover the UE 101 from the serving BS 102 to the target BS 103. In particular, the network apparatus 100 is configured to determine one of the neighbor BSs 104 of the serving BS 102 to be the target BS 103 of the UE 101 based on the enhanced HO procedure. The network apparatus 100 may be the serving BS 102 itself, or may be at least partially included in the serving BS 102 or associated with the serving BS 102.

For the enhanced HO procedure as shown in fig. 2, the network apparatus 100 is configured to obtain FD capability information of each neighbor BS104 of the serving BS 102. The network apparatus 100 is then operable to request and receive UL channel quality measurements for the UE 101 from all of the neighbor BSs 104 (FD and/or HD capable) or a subset of the neighbor BSs 104. Finally, the network apparatus 100 is configured to determine one neighbor BS104 as the target BS 103 based on the obtained FD capability information and the received UL channel quality measurement.

These actions of the network apparatus 100 as shown in fig. 2 correspond to a method 200 for enhanced HO of a UE 101 from a serving BS 102 to a target BS 103 according to another general embodiment of the invention. In a first step, the method 200 comprises obtaining 201 FD capability information of each neighbor BS104 of the serving BS 102. In a second step, the method 200 includes requesting and receiving 202 UL channel quality measurements for the UE 101 from all neighbor BSs 104 (FD and/or HD capable) or a subset of the neighbor BSs 104. In a third step, the method 200 comprises determining 203 one neighbor BS104 as the target BS 103 based on the obtained FD capability information and the received UL channel quality measurements. As exemplarily shown in fig. 2, the method 200 may be performed by the network device 100. However, the method 200 may also be performed in a centralized manner by the serving BS 102 or by another HO decision entity of the network, or in a distributed manner by e.g. cooperation of several BSs 102, 104.

Fig. 3 shows that the above general embodiment of the invention comprises two main parts. The first section relates to BS-related information, and in particular, to acquisition of FD capabilities of neighbor BSs 104. The second section relates to UE-related information, in particular to acquisition of UL channel quality between the UE 101 and the neighbor BSs 104 (in particular, all neighbor BSs 104 or a subset of these neighbor BSs 104).

The first part of the base station concerned is now explained in detail.

In a conventional HO procedure, the serving BS associated with the UE in the mobility scenario only has a list of possible neighbor BSs to which the UE can handover. Only the neighbor cell identifier is stored at the network level and no other information is available.

In particular, Automatic Neighbor Relation (ANR) is defined in 3GPP TS 25.484(3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Automatic Neighbor Relation (ANR) for UTRAN; Stage 2(Release 10)3GPP TS 25.484V10.0.0 (2011-06)). As shown in fig. 11, the ANR function resides in the RNC of the base station, and is composed of a Neighbor Relation Table (NRT) management function, a neighbor detection function (neighbor removal function), and a neighbor removal function (neighbor removal function). The neighbor detection function detects new neighbors and adds these new neighbors to the NRT. The neighbor removal function removes obsolete neighbors. And, the neighbor cell relation (NR) between the reference UTRAN cell and the neighbor cell exists under a set of predefined conditions (details in section 4.1 of TS 25.484). As shown in fig. 12, ANR measurement reports provided by the UE to the receiving RNC of a potential target BS for HO are forwarded to the reference RNC of the serving BS. However, no information about FD capabilities of the neighbor BSs is forwarded.

According to an embodiment of the present invention, the network apparatus 100 (hereinafter, exemplarily in the serving base station 102) perceives the FD capability of the neighbor BS 104. For this purpose, two possible implementations are proposed. For the first implementation, the normalized NRT is changed by adding additional information. For the second implementation, additional message interaction and signaling is provided.

As shown in fig. 4, for the first implementation, a new field 401 is preferably added to the NRT400, where the NRT400 is available to at least the serving BS 102. This new field 401 specifies the FD capabilities of the neighbor BS104 and optionally other useful information such as (but not limited to) the supported bandwidth size on which FD may be performed. The network device 100 may extract FD capability information and optionally additional useful information from the NRT 400.

As shown in fig. 5, for the second implementation, in order to obtain the FD property of the neighbor BS104 (without changing the NRT 400), additional signaling 500 may be performed, wherein the network apparatus 100 in the serving BS 102 is configured to query the neighbor BS104 for its FD property and to receive its reply through "standardized" signaling. Such signaling 500 is interactive over existing backhaul connections, e.g., wired/fiber/wireless backhaul connections over the X2 interface typically used for HO request operations (however, any other backhaul interface or inter-base station interface may also be used). In other words, the network apparatus 100 is configured to obtain the FD capability information through signaling interaction with each neighbor BS 104.

The UE-related second part is now described in detail.

The UL channel quality between a given UE (especially in HO scenarios) and a possible target (neighbor) BS (which is not currently serving the UE) cannot be estimated using current wireless access standards. However, with respect to fig. 6, the following enhanced flow may be applied according to an embodiment of the present invention.

Similar to the conventional HO procedure, the UE 101 measures 601 the channel quality of its serving and neighbor cells, i.e. the UE 101 collects e.g. DL Reference Signal Receiving Power (RSRP) measurements. If the predefined HO condition is verified 602, the UE 101 reports 603 the measurement (e.g., RSRP of BSs in NRT table) to its serving BS 102. Here, the network apparatus 100 is exemplarily again in the serving BS 102.

Next, a new function called FD-aware HO trigger function 700 (see also fig. 7) is activated in the network device 100. The function preferably functions to identify FD capable neighbor BSs 104 of the serving BS 102 to trigger all or a subset of these BSs 104 to perform UL channel measurements. The FD capable neighbor BSs 104 may be identified based on the NRT table or through signaling. The FD-aware HO trigger function may also trigger all or a subset of the HD-capable neighbor BSs 104 to perform UL channel measurements.

The network apparatus 100 is then used to inform 604 each FD-capable (and/or HD-capable) neighbor BS104, i.e. the ID of the UE 101 to be handed over to each potential target BS 103, and other necessary information to initiate UL measurements. In other words, the network apparatus 100 is configured to trigger UL channel quality measurements between the respective neighbor BSs 104 and the UE 101. Accordingly, all notified neighbor BSs 104 evaluate 605 the UL channel quality, e.g. UL RSRP measurement, of the UE 101 under consideration.

The network apparatus 100 is then operable to initiate 606 a HO procedure and determine a newly selected target BS 103, the target BS 103 comprising a link type (with or without FD capability) supported by the UE 101. The target BS 103 may then evaluate 607 whether it can properly serve the considered UE 101, e.g. by evaluating UL and DL quality and availability, and may report 608 back the link type (FD/HD; total band/uplink only band/downlink only band; …) to be established. Then, when the target BS 103 confirms 609 that it can serve the UE 101, a pre-allocation of resources and a standard HO procedure are performed 610 based on the selected option.

Fig. 7 shows a schematic diagram of a network device 100 with FD-aware HO trigger function 700. The network apparatus 100 may receive the FD capability of the neighbor BS104 via the modified NRT 400. Based on the modified NRT400, the FD-aware HO trigger function 700 of the network device 100 selects a set of FD (and/or HD) capable neighbor BSs 104 to request UL measurements from the set of neighbor BSs 104. The network apparatus 100 receives these UL measurements from the neighbor BSs 104 and may also receive DL measurements from the UE 101 directly (if the network apparatus 100 is within the serving BS 102) or via the serving BS 102. Fig. 8 illustrates the signaling interaction in this regard. Then, the network apparatus 100 selects a target BS 103 based on the received measurement and requests a handover to the target BS 103.

Fig. 9 and 10 show two implementations of the network device 100, respectively. The implementation shown in fig. 9 is based on a centralized approach, where the network apparatus 100 (here exemplarily provided in the serving BS 102) collects all measurements, including UL measurements performed by other potential target BSs (neighbor BSs 104), and decides the target BS 103 for handover based on the reported measurements (legacy DL measurements and UL measurements reported by neighbor BSs 104). In particular, the network apparatus 100 may also be the serving BS 102, but may also be a separate entity associated with the serving BS 102.

The implementation shown in fig. 10 is based on a distributed approach, where the network apparatus 100 (illustratively partially provided in the serving BS 102) selects a set of potential target BSs (neighbor BSs 104) for handover. A selected potential target BS is then contacted and decides whether it can accept the handover (considering the UL measurements for the UE 101 under consideration). In other words, here the network device 100 is provided partly in the serving BS 102 and partly in the neighbour BSs 104, i.e. the network device 100 is distributed over these BSs 102, 104.

In general, the conventional handover decision procedure only considers DL measurements reported by the UE as input, whereas the embodiments of the present invention consider additional information about FD capabilities of the neighbor BSs 104 and UL measurements of all or a subset of the neighbor BSs 104 on the UE 101. The corresponding enhanced HO flow follows a two-phase output. First, the network device 100 requests or is notified of additional information. Second, a suitable target BS 103 is selected in consideration of FD capability and UL measurements.

The invention has been described in connection with various embodiments by way of example and implementation. However, other variations can be understood and effected by those skilled in the art and practicing the claimed invention, from a study of the drawings, the disclosure, and the independent claims. In the claims as well as in the specification, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single element or other unit may fulfill the functions of several entities or items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims (12)

1. A network apparatus for deciding to handover a user equipment from a serving base station to a target base station, the network apparatus being configured to:

obtaining full duplex capability information for each neighbor base station of the serving base station,

requesting and receiving uplink channel quality measurements for the user equipment from all or a subset of the neighboring base stations, an

And determining one adjacent base station as the target base station based on the obtained full duplex capability information and the received uplink channel quality measurement.

2. The network device of claim 1, wherein

The network device is configured to extract the full-duplex capability information from a neighbor relation table available to at least the serving base station.

3. The network device of claim 2, wherein

The neighbor relation table includes a field specifying full duplex capability of each neighbor base station of the serving base station.

4. Network device according to claim 2 or 3, wherein

The neighbor relation table includes a field specifying a bandwidth supported by each neighbor base station of the serving base station.

5. The network device of claim 1, wherein

The network device is configured to obtain the full-duplex capability information through signaling interaction with each neighboring base station.

6. The network device of claim 5, wherein

The signaling interaction is performed over a backhaul connection, such as an X2 interface.

7. A network device comprising all the features of the network device according to any one of claims 1 to 6 and,

the network device is configured to provide an identifier of the ue to each neighboring base station, so as to trigger the uplink channel quality measurement between each neighboring base station and the ue.

8. A network device comprising all the features of the network device according to any one of claims 1 to 7 and,

the network device is configured to receive downlink channel quality measurements from the user equipment for all or a subset of the neighbor base stations of the serving base station, and

and further considering the downlink channel quality measurement to determine the target base station.

9. A network device comprising all the features of the network device according to any one of claims 1 to 8 and,

the network device is configured to obtain full duplex capability information from the user equipment, an

Determining the target base station further considering the full-duplex capability information of the user equipment.

10. A network device comprising all the features of the network device according to any one of claims 1 to 9 and,

the network device is, or is included in or associated with, the serving base station.

11. A network device comprising all the features of the network device according to any one of claims 1 to 10 and,

the network device is distributed over the serving base station and the neighbor base stations of the serving base station, wherein

The serving base station is configured to obtain the full-duplex capability information, request the uplink channel quality measurement from all or a subset of the neighbor base stations, determine and notify a potential target base station based on the obtained full-duplex capability information, and

the potential target base station is configured to determine whether the potential target base station becomes the target base station for the handover of the user equipment based on the potential target base station full duplex capability and an uplink channel quality measurement of the user equipment by the potential target base station.

12. A method for handing over a user equipment from a serving base station to a target base station, the method comprising:

obtaining full duplex capability information for each neighbor base station of the serving base station,

requesting and receiving uplink channel quality measurements for the user equipment from all or a subset of the neighboring base stations, an

And determining one adjacent base station as the target base station based on the obtained full duplex capability information and the received uplink channel quality measurement.

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