WO2021073746A1

WO2021073746A1 - Network devices and methods for cell activation/deactivation

Info

Publication number: WO2021073746A1
Application number: PCT/EP2019/078312
Authority: WO
Inventors: Siva VAKEESAR; Ali HAMIDIAN; Antonio Consoli
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2019-10-18
Filing date: 2019-10-18
Publication date: 2021-04-22

Abstract

The invention relates to network devices and corresponding methods for cell activation/deactivation. A first network entity transmits a first message indicating a request for predicted traffic in at least one cell to a second network entity, and thereafter receives a second message indicating a predicted traffic in the at least one cell from the second network entity. Based on the content of the second message an activation or a deactivation of the at least one cell is determined. The first network entity transmits a third message indicating the activation or the deactivation of the at least one cell to a network access node configured to control the at least one cell. Thereby, e.g. improved energy saving in a communication system is possible since and improved cell switching mechanism is provided.

Description

NETWORK DEVICES AND METHODS FOR CELL ACTIVATION/DEACTIVATION

Technical Field

The invention relates to network devices and corresponding methods for cell activation/deactivation.

Background

The number of deployed 4G base stations has increased by multiple folds between the years 2007 and 2012. This trend is still on the rise in 5G because of high-order frequency spectrum in use and gigantic capacity demands. The enormous problem that a network operator faces with this phenomenal growth of base stations is increasing operational expense (OPEX) that is mainly attributed to energy cost. The bases stations accounts for nearly 60% of total energy consumption of a network operator. As a result, energy saving is an important aspect and gaining popularity within 3GPP. Whether to switch on or off a cell requires at least prior knowledge about future traffic in a cell and how many layers of coverage is provided in a given location.

Cell activation and reactivation was used to be a Rel-11 feature in Long Term Evolution (LTE). The purpose of the cell activation procedure is to enable an eNB to send a cell activation request message to a peer eNB to request the re-activation of one or more cells, controlled by the peer eNB and which had been previously indicated as dormant.

Accordingly, switching off actions of one or many cells will be notified to all peer eNBs using the X2 interface by an eNB owning the concerned cells. This is facilitated with an existing eNB configuration update procedure. As a result, all informed nodes maintain up to date information about a cells’ dormant state. If Evolved UTRAN (E-UTRAN) cells provide basic coverage, eNBs owning non-capacity boosting cells may request a re-activation of capacity boosting cells on a demand basis using the X2 interface. This is achieved through the cell activation procedure. If, on the other hand, Universal Terrestrial Radio Access Network (UTRAN) or GSM EDGE Radio Access Network (GERAN) provides basic coverage, the eNB owning the capacity booster cell may receive a re-activation request from a GERAN or UTRAN node using the MME Direct Information Transfer procedure over S1. The eNB owning the capacity booster cell may also receive from the sending GERAN or UTRAN node in terms of minimum time- period a capacity boosting cell has to be operational before it can be switched off; during this time, the same eNB may prevent idle mode UEs from camping on the cell and may prevent incoming handovers to the same cell. The eNB owning the dormant cell should normally obey a request. The switch-on decision may also be taken by Operations, Administration and Management or Operations, Administration and Maintenance (OA&M or OAM). All peer eNBs are informed by the eNB owning the concerned cell about the re-activation by an indication on the X2 interface.

Summary

An objective of embodiments of the invention is to provide a solution which mitigates or solves the drawbacks and problems of conventional solutions.

The above and further objectives are solved by the subject matter of the independent claims. Further advantageous embodiments of the invention can be found in the dependent claims.

According to a first aspect of the invention, the above mentioned and other objectives are achieved with a first network entity configured to transmit a first message to a second network entity, wherein the first message indicates a request for predicted traffic in at least one cell; receive a second message from the second network entity in response to the transmission of the first message, wherein the second message indicates a predicted traffic in the at least one cell; and determine an activation or a deactivation of the at least one cell based on the second message.

The first network entity is configured to communicate in a communication system.

An advantage of the first network entity according to the first aspect is that a novel cell switching on/off mechanism is provided by determining an activation or a deactivation state of the at least one cell based on the second message. Thereby, e.g. improved energy saving in the communication system is possible.

In an implementation form of a first network entity according to the first aspect, the predicted traffic in the at least one cell is associated with a network slice.

An advantage of this implementation form is that a novel cell switching on/off mechanism per slices is provided.

In an implementation form of a first network entity according to the first aspect, the first message further indicates at least one of: an identity of the at least one cell, an identity of a network access node configured to control the at least one cell, and an observation period for the predicted traffic.

The observation period for the predicted traffic can also be given per network slice.

An advantage with this implementation form is that enhancement of analytics subscription with new filters as defined by the above parameters is provided.

In an implementation form of a first network entity according to the first aspect, the second message further includes at least one of: an identity of the at least one cell, an identity of a network access node configured to control the at least one cell, and an observation period for the predicted traffic.

An advantage with this implementation form is that predicted traffic is indicated per an identity of the at least one cell or an identity of a network access node configured to control the at least one cell during the observation period.

In an implementation form of a first network entity according to the first aspect, the first network entity is configured to transmit a third message to a network access node configured to control the at least one cell, wherein the third message indicates the activation or the deactivation of the at least one cell.

An advantage with this implementation form is that a procedure between first network entity and the network access node is introduced to enable selective cell activation/deactivation.

In an implementation form of a first network entity according to the first aspect, the third message further indicates the identity of the at least one cell and a time period for the activation or the deactivation of the at least one cell.

An advantage with this implementation form is that identity of the at least one cell can be passed on to the network access node for selective activation or deactivation of the at least one cell. Further, the time period during which the at least one cell is activated/deactivated is also provided which means improved energy saving.

In an implementation form of a first network entity according to the first aspect, the first network entity is configured to receive a fourth message from the network access node in response to the transmission of the third message, wherein the fourth message indicates an operational status of the at least one cell or a dormant status of the at least one cell.

An advantage with this implementation form is that the first network entity can maintain up to date operational status of the at least one cell within its domain.

In an implementation form of a first network entity according to the first aspect, the first network entity is an access and mobility management function.

According to a second aspect of the invention, the above mentioned and other objectives are achieved with a second network entity configured to receive a first message from a first network entity, wherein the first message indicates a request for predicted traffic in at least one cell; predict traffic in the at least one cell based on the first message and collected traffic data associated with the at least one cell; and transmit a second message to the first network entity, wherein the second message indicates a predicted traffic in the at least one cell.

The second network entity is configured to communicate in a communication system.

An advantage of the second network entity according to the second aspect is that a novel cell switching on/off mechanism is provided by determining by a first network entity an activation or a deactivation state of the at least one cell based on the second message. Thereby, e.g. improved energy saving in the communication system is possible.

In an implementation form of a second network entity according to the second aspect, the first message further indicates at least one of: an identity of the at least one cell, an identity of a network access node configured to control the at least one cell, and an observation period for the predicted traffic. An advantage with this implementation form is that enhancement of analytics subscription with new filters as defined by the above parameters is provided.

In an implementation form of a second network entity according to the second aspect, the second message further includes at least one of: an identity of the at least one cell, an identity of a network access node configured to control the at least one cell, and an observation period for the predicted traffic.

In an implementation form of a second network entity according to the second aspect, the second network entity is a network data analytics function.

According to a third aspect of the invention, the above mentioned and other objectives are achieved with a network access node configured to control at least one cell, and further configured to receive a third message from a first network entity, wherein the third message indicates an activation or a deactivation of the at least one cell; and activate or deactivate the at least one cell based on the third message.

The network access node is configured to communicate in a communication system.

An advantage of the network access node according to the third aspect is that a novel cell switching on/off mechanism is provided by determining an activation or a deactivation state of the at least one cell. Thereby, e.g. improved energy saving in the communication system is possible.

In an implementation form of a network access node according to the third aspect, the third message further indicates the identity of the at least one cell and a time period for the activation or the deactivation of the at least one cell.

In an implementation form of a network access node according to the third aspect, the network access node is configured to determine an operational status or a dormant status of the at least one cell; and transmit a fourth message to the first network entity in response to the reception of the third message, wherein the fourth message indicates the operational status or the dormant status of the at least one cell.

In an implementation form of a network access node according to the third aspect, the network access node is a gNB.

According to a fourth aspect of the invention, the above mentioned and other objectives are achieved with a method for a first network entity, the method comprises transmitting a first message to a second network entity, wherein the first message indicates a request for predicted traffic in at least one cell; receiving a second message from the second network entity in response to the transmission of the first message, wherein the second message indicates a predicted traffic in the at least one cell; and determining an activation or a deactivation of the at least one cell based on the second message.

The method according to the fourth aspect can be extended into implementation forms corresponding to the implementation forms of the first network entity according to the first aspect. Hence, an implementation form of the method comprises the feature(s) of the corresponding implementation form of the first network entity.

The advantages of the methods according to the fourth aspect are the same as those for the corresponding implementation forms of the first network entity according to the first aspect.

According to a fifth aspect of the invention, the above mentioned and other objectives are achieved with a method for a second network entity, the method comprises receiving a first message from a first network entity, wherein the first message indicates a request for predicted traffic in at least one cell; predicting traffic in the at least one cell based on the first message and collected traffic data associated with the at least one cell; and transmitting a second message to the first network entity, wherein the second message indicates a predicted traffic in the at least one cell.

The method according to the fifth aspect can be extended into implementation forms corresponding to the implementation forms of the second network entity according to the second aspect. Hence, an implementation form of the method comprises the feature(s) of the corresponding implementation form of the second network entity.

The advantages of the methods according to the fifth aspect are the same as those for the corresponding implementation forms of the second network entity according to the second aspect.

According to a sixth aspect of the invention, the above mentioned and other objectives are achieved with a method for a network access node, the method comprises receiving a third message from a first network entity, wherein the third message indicates an activation or a deactivation of the at least one cell; and activating or deactivating the at least one cell based on the third message.

The method according to the sixth aspect can be extended into implementation forms corresponding to the implementation forms of the network access node according to the third aspect. Hence, an implementation form of the method comprises the feature(s) of the corresponding implementation form of the network access node.

The advantages of the methods according to the sixth aspect are the same as those for the corresponding implementation forms of the network access node according to the third aspect.

The invention also relates to a computer program, characterized in program code, which when run by at least one processor causes said at least one processor to execute any method according to embodiments of the invention. Further, the invention also relates to a computer program product comprising a computer readable medium and said mentioned computer program, wherein said computer program is included in the computer readable medium, and comprises of one or more from the group: ROM (Read-Only Memory), PROM (Programmable ROM), EPROM (Erasable PROM), Flash memory, EEPROM (Electrically EPROM) and hard disk drive.

Further applications and advantages of the embodiments of the invention will be apparent from the following detailed description.

Brief Description of the Drawings

The appended drawings are intended to clarify and explain different embodiments of the invention, in which:

- Fig. 1 shows a first network entity according to an embodiment of the invention;

- Fig. 2 shows a method for a first network entity according to an embodiment of the invention;

- Fig. 3 shows a second network entity according to an embodiment of the invention;

- Fig. 4 shows a method for a second network entity according to an embodiment of the invention;

- Fig. 5 shows a network access node according to an embodiment of the invention;

- Fig. 6 shows a method for a network access node according to an embodiment of the invention;

- Fig. 7 shows a wireless communication system according to an embodiment of the invention; and

- Fig. 8 shows a signalling diagram illustrating the interaction between the first network entity, the second network entity and the network access node according to embodiments of the invention.

Detailed Description

Predicting future traffic in legacy cellular system is nearly difficult - but with an advent of Artificial Intelligence (Al), big data analysis and use of Network Data Analytics Function (NWDAF), predicting future traffic per cell can be possible. At the moment, the functionality of the NWDAF has been extended to provide a basic mechanism to warn a User Equipment (UE) whenever a Quality-of-Service (QoS) of a Packet Data Unit (PDU) session drops below any pre-agreed performance level. This is called QoS sustainability analytics. Accordingly, any consumer of QoS Sustainability analytics can request the NWDAF for analytics information pertaining to the QoS change statistics for an observation period in the past in a certain area or the likelihood of a QoS change for an observation period in the future in a certain area.

Furthermore, the cell activation and reactivation in LTE was previously described. However, additional functionalities are required for the NWDAF to help decide on switching on/off cells on a need basis. The inventors have therefore identified some issues associated with the existing cell activation procedure, i.e.: neighbour eNBs need to maintain the X2/Xn interface and thus only gNB direct neighbours can send an activation request. This means that only direct neighbours know the active status of a cell. However, wider visibility is possible in case 5GC is involved. Further, the cell activation procedure enables an eNB to request a dormant cell belonging to another eNB to transition into an operational state. In other words, it is not used to put a cell into a dormant mode.

Therefore, the inventors in this disclosure address at least the following objectives. How to switch-on/switch-off cells based on NWDAF input in terms of future predicted traffic per cell/gNB. Further, how to energy save when it is expected that 5G networks, especially because of 5G NR FR2, will contain a higher number of small cells compared to that of a 4G network and operating all cells all the time unnecessarily can be sub-optimal.

Fig. 1 shows a first network entity 100 according to an embodiment of the invention. In the embodiment shown in Fig. 1 , the first network entity 100 comprises a processor 102, a transceiver 104 and a memory 106. The processor 102 may be coupled to the transceiver 104 and the memory 106 by communication means 108 known in the art. The first network entity 100 may further comprise a communication interface 110 coupled to the transceiver 104, which means that the first network entity 100 may be configured for communications in a communication system. That the first network entity 100 may be configured to perform certain actions can in this disclosure be understood to mean that the first network entity 100 comprises suitable means, such as e.g. the processor 102 and the transceiver 104, configured to perform said actions.

The processor 102 of the first network entity 100 may be referred to as one or more general- purpose central processing units (CPUs), one or more digital signal processors (DSPs), one or more application-specific integrated circuits (ASICs), one or more field programmable gate arrays (FPGAs), one or more programmable logic devices, one or more discrete gates, one or more transistor logic devices, one or more discrete hardware components, and one or more chipsets.

The memory 106 of the first network entity 100 may be a read-only memory, a random access memory, or a non-volatile random access memory (NVRAM).

The transceiver 104 of the first network entity 100 may be a transceiver circuit, a power controller, an antenna, or an interface which communicates with other modules or devices. In embodiments, the transceiver 104 of the first network entity 100 may be a separate chipset or being integrated with the processor 102 in one chipset. While in some embodiments, the processor 102, the transceiver 104, and the memory 106 of the first network entity 100 are integrated in one chipset.

According to embodiments of the invention the first network entity 100 is configured to transmit a first message 702 to a second network entity 300 (see Fig. 8). The first message 702 indicates a request for predicted traffic in at least one cell. The first network entity 100 is configured to receive a second message 704 from the second network entity 300 in response to the transmission of the first message 702 (see Fig. 8). The second message 704 indicates a predicted traffic in the at least one cell. The first network entity 100 is configured to determine an activation or a deactivation of the at least one cell based on the second message 704.

In embodiments, the first network entity 100 is an Access and mobility Management Function (AMF).

Fig. 2 shows a flow chart of a corresponding method 200 which may be executed in a first network entity 100, such as the one shown in Fig. 1. The method 200 comprises transmitting 202 a first message 702 to a second network entity 300. The first message 702 indicates a request for predicted traffic in at least one cell. The method 200 comprises receiving 204 a second message 704 from the second network entity 300 in response to the transmission of the first message 702. The second message 704 indicates a predicted traffic in the at least one cell. The method 200 comprises determining 206 an activation or a deactivation of the at least one cell based on the second message 704.

Fig. 3 shows a second network entity 300 according to an embodiment of the invention. In the embodiment shown in Fig. 3, the second network entity 300 comprises a processor 302, a transceiver 304 and a memory 306. The processor 302 is coupled to the transceiver 304 and the memory 306 by communication means 308 known in the art. The second network entity 300 may be configured for communications in a communication system. In this respect the second network entity can comprise a communication interface 310 coupled to the transceiver 304. That the second network entity 300 is configured to perform certain actions can in this disclosure be understood to mean that the second network entity 300 comprises suitable means, such as e.g. the processor 302 and the transceiver 304, configured to perform said actions. The processor 302 of the second network entity 300 may be referred to as one or more general-purpose CPUs, one or more DSPs, one or more ASICs, one or more FPGAs, one or more programmable logic devices, one or more discrete gates, one or more transistor logic devices, one or more discrete hardware components, and one or more chipsets.

The memory 306 of the second network entity 300 may be a read-only memory, a random access memory, or a NVRAM.

The transceiver 304 of the second network entity 300 may be a transceiver circuit, a power controller, an antenna, or an interface which communicates with other modules or devices.

In embodiments, the transceiver 304 of the second network entity 300 may be a separate chipset or being integrated with the processor 302 in one chipset. While in some embodiments, the processor 302, the transceiver 304, and the memory 306 of the second network entity 300 are integrated in one chipset.

According to embodiments of the invention the second network entity 300 is configured to receive a first message 702 from a first network entity 100 (see Fig. 8). The first message 702 indicates a request for predicted traffic in at least one cell. The second network entity 300 is configured to predict traffic in the at least one cell based on the first message 702 and collected traffic data associated with the at least one cell. The second network entity 300 is configured to transmit a second message 704 to the first network entity 100 (see Fig. 8). The second message 704 indicates a predicted traffic in the at least one cell.

In embodiments, the second network entity 300 is a NWDAF.

Fig. 4 shows a flow chart of a corresponding method 400 which may be executed in a second network entity 100, such as the one shown in Fig. 3. The method 400 comprises receiving 402 a first message 702 from a first network entity 100. The first message 702 indicates a request for predicted traffic in at least one cell. The method 400 comprises predicting 404 traffic in the at least one cell based on the first message 702 and collected traffic data associated with the at least one cell. The method 400 comprises transmitting 406 a second message 704 to the first network entity 100. The second message 704 indicates a predicted traffic in the at least one cell.

Fig. 5 shows a network access node 500 according to an embodiment of the invention. In the embodiment shown in Fig. 5, the network access node 500 comprises a processor 502, a transceiver 504 and a memory 506. The processor 502 is coupled to the transceiver 504 and the memory 506 by communication means 508 known in the art. The network access node 500 may be configured for both wireless and wired communications in a communication system. The wireless communication capability is provided with an antenna or antenna array 510 coupled to the transceiver 504, while the wired communication capability is provided with a wired communication interface 512 coupled to the transceiver 504. That the network access node 500 is configured to perform certain actions can in this disclosure be understood to mean that the second network entity 500 comprises suitable means, such as e.g. the processor 502 and the transceiver 504, configured to perform said actions.

The processor 502 of the network access node 500 may be referred to as one or more general- purpose CPUs, one or more DSPs, one or more ASICs, one or more FPGAs, one or more programmable logic devices, one or more discrete gates, one or more transistor logic devices, one or more discrete hardware components, and one or more chipsets.

The memory 506 of the network access node 500 may be a read-only memory, a random access memory, or a NVRAM.

The transceiver 504 of the network access node 500 may be a transceiver circuit, a power controller, an antenna, or an interface which communicates with other modules or devices.

In embodiments, the transceiver 504 of the network access node 500 may be a separate chipset or being integrated with the processor 502 in one chipset. While in some embodiments, the processor 502, the transceiver 504, and the memory 506 of the network access node 500 are integrated in one chipset.

According to embodiments of the invention the network access node 500 is configured to control at least one cell as illustrated in Fig. 7. The network access node 500 is further configured to receive a third message 706 from a first network entity 100 (see Fig. 8). The third message 706 indicates an activation or a deactivation of the at least one cell. The network access node 500 is configured to activate or deactivate the at least one cell based on the third message 706.

In embodiments, the network access node 500 includes but is not limited to: a NodeB in wideband code division multiple access (WCDMA) system, an evolutional Node B (eNB) or an evolved NodeB (eNodeB) in LTE systems, or a relay node or an access point, or an in-vehicle device, a wearable device, or a gNB in the fifth generation (5G) networks. Further, the network access node 500 herein may be denoted as a radio network access node, an access network access node, an access point, or a base station, e.g. a radio base station (RBS), which in some networks may be referred to as transmitter, “gNB”, “gNodeB”, “eNB”, “eNodeB”, “NodeB” or “B node”, depending on the technology and terminology used. The radio network access nodes may be of different classes such as e.g. macro eNodeB, home eNodeB or pico or micro/nano base station, based on transmission power and thereby also cell size. The radio network access node can be a station (STA), which is any device that contains an IEEE 802.11 -conformant MAC and PHY interface to the wireless medium. The radio network access node may also be a base station corresponding to the 5G wireless systems.

Fig. 6 shows a flow chart of a corresponding method 600 which may be executed in a network access node 500, such as the one shown in Fig. 5. The method 600 comprises receiving 602 a third message 706 from a first network entity 100. The third message 706 indicates an activation or a deactivation of the at least one cell. The method 600 comprises activating or deactivating 604 the at least one cell based on the third message 706.

Fig. 7 shows a communication system 700 according to an embodiment of the invention. The communication system 700 can e.g. be of public land mobile network (PLMN) or wireless type of communication system or a combined wired and wireless communication system. A typical example could be a 5G system that consists Radio Access Network (RAN) part and 5G Core (5GC). The basic description of these elements is specified in TS 38.300, TS 23.501 , TS 23.502 and TS 23.503 but are not limited thereto.

The communication system 700 comprises a first network entity 100, a second network entity 300 and a network access node 500. The first network entity 100 and the second network entity 300 are configured to communicate with each other via a first communication interface 710. Further, the first network entity 100 and the network access node 500 are configured to communicate with each other via a second communication interface 720. The network access node 500, e.g. a base station, is configured to control one or more cells 510a, 510b,..., 51 On. Also shown in Fig. 7 is a UE 800 which in this example is located in cell 510b and is configured to communicate in the uplink (UL) and/or the downlink (DL) with the network access node 500 via an air interface according to a communication standard.

Fig. 8 shows a signalling diagram illustrating the interaction between the first network entity 100, the second network entity 300 and the network access node 500 according to embodiments of the invention in a communication system 700. For providing easier understanding of embodiments of the invention, the first network entity 100 act as a AMF, the second network entity 300 act as an NWDAF, and the network access node 500 act as a gNB in Fig. 8. However, embodiments of the invention are not limited to interaction between such entities only.

In step I in Fig. 8, the AMF 100 makes a subscription to the NWDAF 300 for the purpose of getting future predicted traffic in at least one cell that is controlled by a gNB 500. In this respect the AMF 100 transmits a first message 702 to the NWDAF 300, and the first message 702 indicates a request for predicted traffic in at least one cell. Hence, the NWDAF 300 is requested to predict and provide future traffic per identified cell. In this way the AMF 100 can make a decision whether one or more cells should be activated or deactivated.

In embodiments, the predicted traffic in the at least one cell is associated with a network slice which implies that the future traffic per identified cell is per network slice.

In embodiments the first message 702 further indicates at least one of the following parameters: an identity of the at least one cell, an identity of the gNB 500 configured to control the at least one cell, and an observation period T for the predicted traffic. It can optionally include network slice for which predicted traffic is required. Hence, in this embodiment further parameters are indicated in the first message 702 to the NWDAF 300.

For example, each cell can be identified by Physical Cell ID (PCI) or NR Cell Global Identifier/E- UTRAN Cell Global Identifier (NCGI/ECGI) while the gNB 500 can be identified by a global gNB ID. The AMF 100 can also get bulk traffic per Tracking Area Identifier (TAI). Such a subscription can expect a single response or regular responses from the NWDAF 300, if periodicity is indicated in the subscription.

Regarding the observation period T, the NWDAF 300 is often expected to predict traffic for a future time period T (e.g., 5 minutes) starting from start time t1 (e.g., 11 pm tomorrow).

In step II in Fig. 8, the NWDAF 300 upon receiving the first message 702 from the AMF 100 will start collecting prediction related data per identified cells/gNB for the identified observation period T. The NWDAF 300 can predict future traffic per target cell/gNB based on mechanisms such as QoS sustainability analytics where the NWDAF 300 knows the QoS requirements of different UEs and theirflightpath as specified in e.g. TS 23.288 V16.1.0. Also, other mechanism as explained in patent application PCT/EP2019/055814 can be used. In addition, the NWDAF 300 may use UE history information, handover restriction list TAU per cell, service request history per identified cells, etc. One or more of the following analytics functions that can be found in TS 23.288 V16.1.0 can also be used by the NWDAF 300 for predicting the traffic, i.e.:

• UE related analytics such as: o UE mobility analytics o UE communication analytics

• User data congestion analytics;

• Network performance analytics;

• QoS sustainability analytics; and

• Slice load level related network data analytics.

In step III in Fig. 8, the NWDAF 300 notifies the AMF 100 about the future expected traffic per in the at least one cell by transmitting a second message 704 to the AMF 100.

In embodiments, the second message 704 further includes at least one of the following parameters: an identity of the at least one cell, an identity of the gNB 500 configured to control the at least one cell, and the observation period T for the predicted traffic. The AMF 100 uses these additional parameters to decide which cell to activate/deactivate, identify which gNB serves a given cell that needs to be activated/deactivated and for how long time period.

In step IV in Fig. 8, the AMF 100 determines an activation or a deactivation of the at least one cell based on the content of the second message 704. It is noted that the AMF 100 is often expected to maintain current (de)activation status of each cell within its domain before deciding on an operational status of different cell based on the parameters in the second message 704. Therefore, the AMF 100 should in such cases know the current status of the one or more cells.

In step V in Fig. 8, the AMF 100 transmits a third message 706 to the gNB 500 indicating the activation or the deactivation of the at least one cell and hence trigger a new cell activation/deactivation procedure.

In embodiments, the third message 706 further indicates the identity of the at least one cell and a time period for the activation or the deactivation of the at least one cell.

In step VI in Fig. 8, the gNB 500 upon receiving the third message 706 activates or deactivates the at least one cell based on the content of the third message 706. The gNB 500 further determines an operational status or a dormant status of the at least one cell. In step VII in Fig. 8, the gNB 500 transmits a fourth message 708 to the AMF 100 and the fourth message 780 indicates the current operational status or a dormant status of the at least one cell.

In step VIII in Fig. 8, the AMF 100 upon receiving the fourth message 708 from the gNB 500 updates its local table maintaining the current operational status of each cell within its domain and for how long the current operational status of each cell will persist.

It is to be understood that depending on whether traffic is expected or not per a target gNB/cell, the NWDAF 300 can assist the AMF 100 and indirectly the gNB 500 to make switching decisions for its controlled cells. Activation and deactivation of cells can be performed in different levels in terms of whether one or many S-NSSAIs are activated/deactivated or a full cell is activated/deactivated.

Switching on/off can be different in uplink and downlink control channels and/or in uplink and downlink data channels. Some activation cases, such as when a UE camp on a cell, may require cells to only broadcast basic System Information (SI) and/or synchronization channel. Such a basic activation may further be augmented with activation of random access channel when a UE wants to send an initial request according to an random access procedure.

Another example of (de)activation can be per frequency spectrum or in terms of different layers of coverage for saving energy in the communication system.

Furthermore, any method according to embodiments of the invention may be implemented in a computer program, having code means, which when run by processing means causes the processing means to execute the steps of the method. The computer program is included in a computer readable medium of a computer program product. The computer readable medium may comprise essentially any memory, such as a ROM (Read-Only Memory), a PROM (Programmable Read-Only Memory), an EPROM (Erasable PROM), a Flash memory, an EEPROM (Electrically Erasable PROM), or a hard disk drive.

Moreover, it is realized by the skilled person that embodiments of the first network entity, the second network entity and the network access node comprise the necessary communication capabilities in the form of e.g., functions, means, units, elements, etc., for performing the solution. Examples of other such means, units, elements and functions are: processors, memory, buffers, control logic, encoders, decoders, rate matchers, de-rate matchers, mapping units, multipliers, decision units, selecting units, switches, interleavers, de-interleavers, modulators, demodulators, inputs, outputs, antennas, amplifiers, receiver units, transmitter units, DSPs, MSDs, TCM encoder, TCM decoder, power supply units, power feeders, communication interfaces, communication protocols, etc. which are suitably arranged together for performing the solution.

Especially, the processor(s) of the first network entity, the second network entity and the network access node may comprise, e.g., one or more instances of a Central Processing Unit (CPU), a processing unit, a processing circuit, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The expression “processor” may thus represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones mentioned above. The processing circuitry may further perform data processing functions for inputting, outputting, and processing of data comprising data buffering and device control functions, such as call processing control, user interface control, or the like.

Finally, it should be understood that the invention is not limited to the embodiments described above, but also relates to and incorporates all embodiments within the scope of the appended independent claims.

Claims

1 . A first network entity (100) configured to transmit a first message (702) to a second network entity (300), wherein the first message (702) indicates a request for predicted traffic in at least one cell; receive a second message (704) from the second network entity (300) in response to the transmission of the first message (702), wherein the second message (704) indicates a predicted traffic in the at least one cell; and determine an activation or a deactivation of the at least one cell based on the second message (704).

2. The first network entity (100) according to claim 1 , wherein the predicted traffic in the at least one cell is associated with a network slice.

3. The first network entity (100) according to claim 1 or 2, wherein the first message (702) further indicates at least one of: an identity of the at least one cell, an identity of a network access node (500) configured to control the at least one cell, and an observation period for the predicted traffic.

4. The first network entity (100) according to any one of the preceding claims, wherein the second message (704) further includes at least one of: an identity of the at least one cell, an identity of a network access node (500) configured to control the at least one cell, and an observation period for the predicted traffic.

5. The first network entity (100) according to any one of the preceding claims, configured to transmit a third message (706) to a network access node (500) configured to control the at least one cell, wherein the third message (706) indicates the activation or the deactivation of the at least one cell.

6. The first network entity (100) according to claim 5 when dependent on claim 4, wherein the third message (706) further indicates the identity of the at least one cell and a time period for the activation or the deactivation of the at least one cell.

7. The first network entity (100) according to claim 5 or 6, configured to receive a fourth message (708) from the network access node (500) in response to the transmission of the third message (706), wherein the fourth message (708) indicates an operational status of the at least one cell or a dormant status of the at least one cell.

8. The first network entity (100) according to any one of the preceding claims, wherein the first network entity (100) is an access and mobility management function.

9. A second network entity (300) configured to receive a first message (702) from a first network entity (100), wherein the first message (702) indicates a request for predicted traffic in at least one cell; predict traffic in the at least one cell based on the first message (702) and collected traffic data associated with the at least one cell; and transmit a second message (704) to the first network entity (100), wherein the second message (704) indicates a predicted traffic in the at least one cell.

10. The second network entity (300) according to claim 9, wherein the first message (702) further indicates at least one of: an identity of the at least one cell, an identity of a network access node (500) configured to control the at least one cell, and an observation period for the predicted traffic.

11 . The second network entity (300) according to claim 9 or 10, wherein the second message (704) further includes at least one of: an identity of the at least one cell, an identity of a network access node (500) configured to control the at least one cell, and an observation period for the predicted traffic.

12. The second network entity (300) according to any one of claims 9 to 11 , wherein the second network entity (300) is a network data analytics function.

13. A network access node (500) configured to control at least one cell, and further configured to receive a third message (706) from a first network entity (100), wherein the third message (706) indicates an activation or a deactivation of the at least one cell; and activate or deactivate the at least one cell based on the third message (706).

14. The network access node (500) according to claim 13, wherein the third message (706) further indicates the identity of the at least one cell and a time period for the activation or the deactivation of the at least one cell.

15. The network access node (500) according to claim 13 or 14, configured to determine an operational status or a dormant status of the at least one cell; and transmit a fourth message (708) to the first network entity (100) in response to the reception of the third message (706), wherein the fourth message (708) indicates the operational status or the dormant status of the at least one cell.

16. The network access node (500) according to any one of claims 13 to 15, wherein the network access node (500) is a gNB.

17. A method (200) for a first network entity (100), the method (200) comprising transmitting (202) a first message (702) to a second network entity (300), wherein the first message (702) indicates a request for predicted traffic in at least one cell; receiving (204) a second message (704) from the second network entity (300) in response to the transmission of the first message (702), wherein the second message (704) indicates a predicted traffic in the at least one cell; and determining (206) an activation or a deactivation of the at least one cell based on the second message (704).

18. A method (400) for a second network entity (300), the method (400) comprising receiving (402) a first message (702) from a first network entity (100), wherein the first message (702) indicates a request for predicted traffic in at least one cell; predicting (404) traffic in the at least one cell based on the first message (702) and collected traffic data associated with the at least one cell; and transmitting (406) a second message (704) to the first network entity (100), wherein the second message (704) indicates a predicted traffic in the at least one cell.

19. A method (600) for a network access node (500), the method (600) comprising receiving (602) a third message (706) from a first network entity (100), wherein the third message (706) indicates an activation or a deactivation of the at least one cell; and activating or deactivating (604) the at least one cell based on the third message (706).

20. A device comprising: a processor, and a memory coupled to the processor and having processor-executable instructions stored thereon, which when executed by the processor, cause the processor to perform the method of claim 18 or 19. 20. A computer program with a program code for performing a method according to claim 18 or 19 when the computer program runs on a computer.