Paging configuration and power saving for inactive or idle wireless mobile terminals

Abstract

Methods and devices for paging configuration and power saving in wireless terminal devices are disclosed. The disclosed method may be performed by a wireless terminal device. The method may include receiving paging subgroup configuration information from a wireless network; determining a paging subgroup identifier based on the paging subgroup configuration information and a paging subgroup mode of the wireless terminal device; and determining whether to wake up to monitor the paging occasion based on whether the paging subgroup identifier is indicated before the paging occasion arrives.

Description

[0001] This divisional application is a divisional application of Chinese Patent Application No. 202180103284.5 with the invention title of "Paging Configuration and Power Saving for Inactive or Idle Wireless Mobile Terminals" filed on October 21, 2021. Technical Field

[0002] The present disclosure generally relates to wireless communication network technologies, and particularly to paging configuration and power saving in wireless terminal devices. Background Art

[0003] In a wireless communication system, a paging mechanism can be employed to initiate an active communication between a radio access network node and a wireless terminal device that was originally in an idle state. The frequency at which the wireless terminal device wakes up from its idle state to check for paging information directly affects the power consumption and battery consumption of the terminal device. Therefore, it is desirable to reduce the ratio of false paging alert situations where the wireless terminal device wakes up to monitor paging information but only finds that the wireless terminal device is not the target. Summary of the Invention

[0004] The present disclosure relates to paging configuration and power saving in wireless terminal devices.

[0005] In one embodiment, a method performed by a wireless terminal device is disclosed. The method may include receiving paging subgroup configuration information from a wireless network; determining a paging subgroup identifier based on the paging subgroup configuration information and the paging subgroup mode of the wireless terminal device; and determining whether to wake up to monitor a paging occasion based on whether the paging subgroup identifier is indicated before the paging occasion arrives.

[0006] In another embodiment, a method performed by a radio access network node to page a wireless terminal device is disclosed. The method includes: determining a paging occasion associated with the wireless terminal device when the wireless terminal is to be paged; determining a paging subgroup identifier of the wireless terminal device within one of two congruent but independent partitions of a two-partition paging subgroup identifier space. The method may further include sending a signaling message before the paging occasion to: indicate to the wireless terminal device that, in addition to other paging subgroup identifiers, the paging subgroup identifier is also activated, and cause the wireless terminal device to wake up to monitor the paging occasion.

[0007] In another embodiment, a wireless terminal device or a radio access network node including a processor and a memory is disclosed. The processor may be configured to read computer code from the memory to implement any one of the above methods.

[0008] In yet another embodiment, a computer program product is disclosed, including a non-transitory computer-readable program medium having computer code stored thereon. The computer code, when executed by a processor, can cause the processor to implement any of the above methods.

[0009] The above embodiments and other aspects and alternatives of their implementations are described in more detail in the following drawings, specification, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 An example wireless communication network including a radio access network, a core network, and a data network is illustrated.

[0011] Figure 2 An example radio access network is illustrated, which includes a plurality of wireless terminals and radio access network nodes communicating with each other via an air communication interface.

[0012] Figure 3 An example wireless communication resource grid in the time domain and frequency domain is illustrated.

[0013] Figure 4 An example paging cycle including an example paging occasion and a paging message is illustrated.

[0014] Figure 5 An example arrangement of paging frames, paging occasions, and paging messages in a paging cycle is illustrated.

[0015] Figure 6 An example logical flow of paging group configuration and paging process is illustrated.

[0016] Figure 7 An example single-stage paging grouping scheme is illustrated.

[0017] Figure 8 Another example single-stage paging grouping scheme is illustrated.

[0018] Figure 9 An example two-stage paging grouping scheme is illustrated.

[0019] Figure 10 Another example two-stage paging grouping scheme is illustrated. DETAILED DESCRIPTION

[0020] The techniques and example embodiments and / or examples described in this disclosure can be used to reduce the power consumption of a wireless terminal device that utilizes paging services from a wireless network. The term "exemplary" is used to mean "an example of...", and unless otherwise stated, does not imply an ideal or preferred example, embodiment, or example. The section headings used in this disclosure are for ease of understanding the disclosed embodiments and are not intended to limit the techniques disclosed in each section to the corresponding section only. The disclosed embodiments can also be implemented in various different forms, and thus, the scope of this disclosure or the claimed subject matter is intended to be construed as not limited to any of the embodiments set forth below. The various embodiments can be implemented as a method, device, component, system, product, or non-transitory computer-readable medium. Thus, the embodiments of this disclosure can, for example, take the form of hardware, software, firmware, or any combination thereof.

[0021] This disclosure relates to methods, systems, and devices related to a wireless access network, and more particularly, to embodiments that facilitate reducing the power consumption in a wireless terminal device that receives services from a wireless network when paged. Although this disclosure provides example embodiments in some specific generations of cellular network systems, the basic principles also apply to other generations of cellular network systems and other general non-cellular wireless network systems.

[0022] Overview of Wireless Network

[0023] Figure 1 The example wireless communication network shown as 100 can include wireless terminals or user equipment (UE) 110, 111, and 112, a bearer network 102, various service applications 140, and other data networks 150. For example, the bearer network 102 can include access networks 120 and 121, and a core network 130. The bearer network 110 can be configured to send voice, data, and other information (collectively referred to as data traffic) between the UEs 110, 111, and 112, between a UE and the service application 140, or between a UE and the other data network 150. The access networks 120 and 121 can be configured as various wireless access network nodes (WANN, alternatively referred to as base stations) to interact with a UE on one side of a communication session and the core network 130 on the other side. The core network 130 can include various network nodes configured to control communication sessions and perform network access management and traffic routing. The service applications 140 can be hosted by various application servers deployed outside the core network 130 but connected to the core network 130. Similarly, the other data networks 150 can also be connected to the core network 130.

[0024] In Figure 1In the wireless communication network 100, UEs can communicate with each other via the radio access network. For example, UEs 110 and 112 can be connected to the same access network 120 and communicate via the same access network 120. UEs can communicate with each other via both the access network and the core network. For example, UE 110 can be connected to access network 120, while UE 111 can be connected to access network 121, and thus, UEs 110 and 111 can communicate with each other via access networks 120 and 121 and communicate with the core network 130. UEs can also communicate with service applications 140 and data networks 150 via the core network 130. In addition, UEs can communicate directly with each other via sidelink communication as shown by 113.

[0025] Figure 2 An example system diagram of the radio access network 120 is also shown, which includes a WANN 202 that serves UEs 110 and 112 via an air interface 204. Each of UEs 110 and 112 can be a mobile or fixed terminal device that is equipped with a mobile access unit such as a SIM / USIM module for accessing the wireless communication network 100. UEs 110 and 112 can be implemented as terminal devices, including but not limited to mobile phones, smart phones, tablets, laptop computers, in-vehicle communication equipment, roadside communication equipment, sensor devices, smart appliances (such as TVs, refrigerators, and ovens), or other devices capable of wireless communication via a network. For some of these devices, especially those that operate on batteries, it may be crucial to keep their power consumption low. As Figure 2 shown, each UE such as UE 112 can include transceiver circuitry 206 that is coupled to one or more antennas 208 to enable wireless communication with the WANN 120 or with another UE such as UE 110. The transceiver circuitry 206 can also be coupled to a processor 210, which can also be coupled to a memory 212 or other storage devices. The memory 212 can be transient or non-transient and can store computer instructions or code therein, which, when read and executed by the processor 210, cause the processor 210 to implement the various methods described herein.

[0026] Similarly, the WANN 120 may include a base station or other radio network access point capable of wirelessly communicating with one or more UEs via the air interface 204 and communicating with the core network 130. For example, the WANN 120 may be implemented in the form of a 2G base station, 3G nodeB, LTE eNB, 4G LTE base station, 5G NR base station, 5G central unit base station, or 5G distributed unit base station, but is not limited thereto. Each type of these WANNs may be configured to perform a corresponding set of radio network functions. The WANN 202 may include transceiver circuitry 214 coupled to one or more antennas 216, and the one or more antennas 216 may include various forms of antenna towers 218 to enable wireless communication with the UEs 110 and 112. The transceiver circuitry 214 may be coupled to one or more processors 220, and the one or more processors 220 may also be coupled to a memory 222 or other storage device. The memory 222 may be transient or non-transient, and instructions or code may be stored therein, which when read and executed by the processor 220 cause the processor 220 to implement the various functions of the WANN 120 described herein.

[0027] The radio transmission resources for the air interface 204 include frequency, time, and space resources. For example, the available frequency and time resources (alternatively referred to as radio resources or radio transmission resources) available for wireless communication are illustrated as 300 in Figure 3 . The transmission resource 300 includes time-domain resources and frequency-domain resources that can be allocated to carry downlink (DL) or uplink (UL) data or control information. The transmission resource 300 may also be divided into multiple partitions to support more flexible transmission resource scheduling, configuration, and allocation. For example, in the time domain, the transmission resource 300 may be divided into M partitions, and in the frequency domain, the transmission resource 300 may be divided into N partitions. Thus, the transmission resource 300 can be considered as a resource grid including M*N resource partitions. Both M and N are positive integers. In Figure 3 , 312 and 314 are shown as two example partitions. Organizing the transmission resource 300 into Figure 3 resource partitions facilitates more efficient resource allocation, configuration, and utilization.

[0028] The time and frequency of the radio resource 300 can be divided at various levels. Figure 3Only an example division at a specific level is shown. The configuration and identification of time and frequency resources can be performed at any level. For example, the wireless resource 300 can be divided into resource blocks (RBs), which represent the smallest units of wireless resources that can be allocated to a UE to communicate with a WANN. Each RB can be further divided in time and frequency into individually identifiable and configurable subunits. For example, in the frequency domain, an RB can be divided into a configurable number of subcarriers with a configurable subcarrier spacing. In the time domain, an RB can occupy a time slot with a configurable time length, which can be further divided into multiple time units, each corresponding to a symbol in, for example, orthogonal frequency division multiplexing (OFDM) or other modulation schemes. Each unit containing subcarriers in the frequency domain and symbols in the time domain can be referred to as a resource element (RE), which represents the smallest identifiable and configurable unit of the wireless resource 300. The wireless resource 300 can be allocated and configured at a higher level. For example, in the time domain, a subframe can include a predetermined number (e.g., 7) of time slots, and a frame can include a predetermined number (e.g., 2) of subframes. As another example, subcarrier blocks in multiple RBs in the frequency domain can be organized into various frequency channels, each frequency channel being assigned for different purposes of transmitting data and control information. These frequency channels can include, but are not limited to, uplink frequency channels (such as the physical uplink shared channel (PUSCH), physical uplink control channel (PUCCH), etc.) and downlink frequency channels (such as the physical downlink shared channel (PDSCH), physical uplink control channel (PDCCH), etc.). Although the term "frequency channel" is used to refer to a set of subcarriers in a specific frequency range, the term "channel" itself can be used to refer to a broader concept of resource units that are not limited to the frequency domain.

[0029] Although the above description focuses on the time and frequency resources 300, it can be combined with spatial multiplexing based on the use of multiple antennas and beamforming in wireless transmission. The allocation and configuration of such spatial resources can be part of the overall wireless resource allocation and configuration. The underlying principles of the various embodiments included in this disclosure are intended to apply to wireless resource allocation and configuration that includes all time, frequency, and spatial dimensions. The above wireless resources can be configured or allocated for various paging functions as described below.

[0030] Power Saving and Paging Mechanism of UE in Idle State

[0031] In Figure 1In the wireless communication system 100 and other wireless communication systems, a UE can operate in an active or idle (or inactive, or sleep) state (or mode). When there is an active communication session between the UE and the access network, the UE is in the active mode. Otherwise, the UE may be in the idle or inactive state. When the UE is idle, it can turn off most of its operations to reduce power consumption and minimize battery drain. However, the UE can continue to perform limited functions, such as waking up (pre-configured or by signaling) from time to time to monitor whether it needs to enter any active communication session. If so, then the UE transitions to the active state. Otherwise, the UE returns to the idle state and waits for the next wake-up to monitor again. In various generations of cellular radio networks, a UE may be in the Radio Resource Control (RRC) active state or the RRC idle state.

[0032] For example, when communication to or from Figure 1 a particular UE 110 is needed or requested (solicitated) (e.g., when communication with the UE 110 is requested by another UE (such as 112), by any other component of the bearer network 102, or by the data network 150 or the service application 140), Figure 1 the bearer network 102 of

[0033] can utilize a paging mechanism to alert that particular UE 110 to use the access network via the air interface. In some embodiments of the paging mechanism, a radio access network node can be configured to broadcast paging configuration information at pre-configured or dynamically configured frequency and time resources. UEs in the tracking area of the radio access network node or otherwise registered with the radio access network node can be correspondingly configured to wake up when they are in the idle state to monitor these frequency and time resources. The paging configuration information can, for example, contain the identification of one or more subsequent network resources allocated for carrying paging information. The UE can then receive the paging information at the network resources identified in the paging configuration information. Figure 4 illustrates an exemplary embodiment of a paging cycle 410. In each paging cycle, UEs within the tracking area of a radio access network node in the idle or inactive state can wake up to Figure 4Monitor paging DCI 412 at the specific time indicated in []. Thus, paging DCI can alternatively be referred to as a paging occasion (PO). As an example, paging DCI 412 can be sent on a physical downlink control channel (PDCCH). In some specific embodiments, the format of paging DCI 412 can include DCI format 1_0.

[0034] After waking up to monitor and receive paging DCI 412, the UE can also receive a paging message 414 according to the network resource configuration and scheduling information included in the paging DCI 412. For example, the paging message 414 can be carried on a physical downlink shared channel (PDSCH). The paging message can be targeted at a specific UE. The identifier of the specific target UE can be included in the paging message. An example of such an identifier of a target UE in a fifth-generation wireless cellular network can be implemented as a fifth-generation system temporary mobile subscription identifier (5G-S-TMSI). The UE can process the received paging message 414 and determine whether it is the target of the paging message 414 by determining whether the identifier of the target UE specified in the paging message 414 matches its own network ID. If so, then it further processes the paging message and responds to the paging message. Otherwise, it returns to the sleep state and waits to wake up again at its next PO (or paging DCI).

[0035] There may be multiple paging requests for each UE during the paging cycle 410. In the regulation, as Figure 5 shown in [], the paging cycle 410 can also be divided into multiple paging frames (N, representing the number of configured paging frames per paging cycle), as Figure 5 shown in 502, 504, and 506 of []. Each paging frame can be configured with multiple POs (N S , representing the number of paging occasions or paging DCIs configured per paging frame), as Figure 5 shown in 510, 512, and 514 for paging frame 502 of []. Each paging frame can correspondingly include N S or other numbers of paging messages, as Figure 5 shown in 520, 522, and 524 for paging frame 502 of [].

[0036] Using Figure 4 or Figure 5For paging configurations, if a UE is configured to monitor each PO and then identify and process the corresponding paging message, the UE may wake up and only find that the paging message is targeted at some other UE. Such a PO constitutes a false alarm for this UE and can lead to a large amount of unnecessary power consumption and battery drain of the UE. To reduce power consumption, in some embodiments, potential UEs within the tracking area of a radio access network node can be divided into groups, and each group can be associated with a subset of POs. Thus, multiple UEs can be configured to form a group to monitor a specific PO of a specific paging frame in a paging cycle. Other UEs that do not belong to this group will sleep during this specific PO to save power. Similarly, another group of UEs can be configured to wake up only to monitor another specific PO of the paging frame in the paging cycle, and the remaining UEs can be configured to sleep during this PO of the paging frame. In other words, each PO in a paging frame can be associated with a group of potential UEs. In such an embodiment, the UE only needs to wake up at the PO associated with the UE group to which it belongs and sleep during other POs.

[0037] In some further embodiments, each group of UEs configured to monitor the same PO can be divided into subgroups to further promote power savings. For example, once the UEs are divided into subgroups, the network can additionally send a signaling message before sending the PO corresponding to the UE group to indicate the subgroup(s) to which the paged UE(s) in the PO belong. Monitoring such a signaling message may only require minimal functional support at the UE (e.g., UEs in the UE group do not need to fully wake up to monitor the signaling message). Thus, only the subgroup of UEs within the UE group associated with the PO involved in the signaling message needs to wake up to receive the PO and the paging message, thereby further reducing the power consumption of UEs outside the subgroup(s) involved (or activated).

[0038] Sub - grouping of UEs for Power Saving

[0039] The various ways in which a UE paging group can be divided into subgroups for paging purposes are described in more detail below. In some embodiments, UEs can be sub-grouped based on their network identifiers (referred to as UE IDs in this disclosure). For example, in sub-grouping based on UE IDs, a subgroup identifier for the UE paging subgroup to which a specific UE belongs can be calculated based on, for example, the 5G-S-TMSI of the UE. Any of various predetermined optional algorithms known to both the radio access network node and the UE can be selected for uniquely converting the UE identifier into a paging subgroup identifier.

[0040] In some other embodiments, the sub-grouping of UEs can be done by Figure 1is determined by the core network (CN) 130. For example, a subgroup identifier of a UE can be assigned by the core network, such as by an access management function (AMF) network node in a fifth-generation cellular radio access network. Such a UE paging subgrouping by the CN can be referred to as CN-based UE subgrouping and can be based on, for example, paging probability, power distribution, and / or other characteristics of the UE. For any of the above types of paging subgroup determination methods, each subgroup identifier can represent a subgroup of UEs having a UE paging group.

[0041] In some embodiments, each RAN (or the radio access network nodes therein) can be responsible (based on, for example, the capabilities of the RAN) for determining the maximum number of paging subgroups based on the UE ID (denoted by N sg ), while the CN can be responsible for determining the maximum number of UE paging subgroups assigned by the CN (denoted by N CN ).

[0042] Generally speaking, UE subgrouping based on the UE ID can be considered somewhat random because the UE ID usually may not carry much information about the UE paging probability. On the other hand, CN-based UE subgrouping can be more based on UE characteristics such as paging probability. Thus, CN-based UE subgrouping can have the advantage of grouping together UEs that will be similar in terms of network characteristics related to paging, such as paging probability.

[0043] In some embodiments, the RAN can support both UE subgrouping based on the UE ID and CN-based UE subgrouping. In such embodiments, the total number of UE subgroups based on the UE ID and CN-based UE subgroups can be limited to the maximum number of UE subgroups of the UE group, denoted by N max . In some embodiments, some UEs can only support subgrouping based on the UE ID or may not be assigned a subgroup ID by the CN, while other UEs, in addition to or as an alternative to supporting subgrouping based on the UE ID, can be capable of receiving subgroup assignments from the CN.

[0044] In an implementation of UE paging subgroups based on both UE-ID and CN allocation, the CN may allocate some UEs to a paging subgroup, which may also include some other UEs that happen to fall into the subgroup due to their UE-ID for a RAN. A UE subgroup corresponding to a specific UE subgroup identifier may thus contain both UEs allocated by the CN and UEs with random UE-IDs. In other words, although the CN allocation of UEs to a specific subgroup may be intended to have similar UEs in the specific subgroup (e.g., in terms of UE paging probability), the actual UE subgroup may end up with UEs having significantly different paging probabilities. In such an implementation, UEs with a lower paging probability in a paging subgroup with a mixed paging probability will suffer from a higher false alarm rate and undesired power consumption and battery drain.

[0045] Additionally, since the core network can manage RANs with different capabilities and UEs may move frequently between tracking areas of various RANs, the CN may need to perform an overall UE subgroup allocation for UEs that support CN-based subgrouping. Thus, the number of UE subgroups that the CN can allocate may be greater than the maximum number of UE paging subgroups that can be supported and determined by a particular RAN with lower capabilities.

[0046] Various further implementations described below for determining a paging subgroup identifier for either or both of UE-ID-based subgrouping and / or CN-based subgrouping are designed to provide a scheme that assigns a unique paging subgroup identifier to similar UEs (e.g., in terms of paging probability). Such paging subgroup identification can be implemented in a single-level or multi-level grouping scheme. The disclosed scheme makes it more likely that UEs determined by the CN with similar paging characteristics are grouped together under a specific subgroup identifier and that there are no other UEs with random characteristics, thereby reducing power consumption and battery drain and avoiding unnecessary PO monitoring and paging message processing for at least some UEs.

[0047] Figure 6 An example general logic flow 600 for implementing the various paging subgrouping mechanisms described in the present disclosure is shown. As Figure 6As shown in 602, the network side 610 can first broadcast, multicast or unicast a paging subgroup policy and send other supplementary information data items for the UE 620 to determine its paging subgroup ID, which can be a single-level subgroup ID or a multi-level subgroup ID. Such information can include other paging information, such as paging group information, paging cycle information, paging frame information and PO configuration information, as well as any other information that can be used by the UE to perform subgroup determination. Such information can be sent from the radio network to the UE, for example, via a radio access network node of the UE's serving cell, as a single control message or a set of messages. These messages can be of a single signaling type or a mixed type, can be sent via a single or mixed control or data channel, and can be one of broadcast, multicast or unicast messages or any combination thereof. Such information can be collectively referred to as paging subgroup configuration information. Such information items can be received by the UE and used to obtain its paging subgroup ID in step 604. The paging subgroup ID can be associated with the PO during the paging frame (together with other subgroup IDs of the same PO). During the RRC idle / inactive mode, the UE can then wake up, monitor or sleep during the PO according to its paging subgroup ID, as shown in step 606. Specific example processes for the UE to wake up to monitor the PO or sleep during the PO can include the following:

[0048] · Step (a): The UE can attempt to receive a message before the PO to check the paging subgroup information or indication carried in the message. Go to step (b).

[0049] · Step (b): If the subgroup information or indication carried in the message matches the subgroup ID obtained in step 2 of Figure 6 then go to step (c), otherwise go to step (d).

[0050] · Step (c): The UE wakes up to monitor the PO.

[0051] · Step (d): The UE does not wake up to monitor the PO (or sleeps during the PO).

[0052] The message used in step (a) can be implemented as various types of control messages. For example, it can be implemented as a DCI message. Such a DCI message can carry information about the paging subgroup within the paging group that may need to wake up to receive the corresponding PO. For example, such information can be included as:

[0053] · A bitmap, each bit representing a paging subgroup or a set of paging subgroups (see the set of paging subgroups in the two-level subgroup example described below). If a bit is set to 1 (or 0), it means that the subsequent paging information is for the subgroup or set of subgroups it represents.

[0054] · Alternatively, code points. For example, the code 0000 0000 can represent a subgroup or a set of subgroups with ID = 0, and the code 0000 0001 can represent a subgroup or a set of subgroups with ID = 1, and so on.

[0055] Single - level Sub - grouping

[0056] In some example embodiments, a single - level sub - grouping scheme can be used, where each subgroup ID contains a single identification value in the paging subgroup ID space. For example, all paging subgroups can be consecutively numbered with corresponding subgroup IDs. In such a single - level sub - grouping scheme, the paging subgroups based on the UE ID and the paging subgroups assigned by the CN can be separate rather than mixed. For example, the single - level paging subgroup ID space can be bifurcated or divided into two separate partitions, one for the subgroups based on the UE ID and the other for the subgroups assigned by the CN.

[0057] In the first example, the subgroups based on the UE ID can form a partition of the paging UE subgroups whose ID numbers are lower than the partition formed by the UE paging subgroups assigned by the CN in the single - level paging subgroup ID space. In the second example, the subgroups based on the UE ID can form a partition of the paging UE subgroups whose ID numbers are greater than the partition formed by the UE paging subgroups assigned by the CN in the single - level paging subgroup ID space. In some other examples, the two paging subgroup ID partitions can be interleaved or arranged in other predefined patterns rather than being bifurcated in the single - level paging subgroup ID space, as long as they are not mixed (i.e., each partition can be assigned to multiple parts of the paging subgroup ID space, and each part of the partition does not contain subgroup IDs that support both UEs with subgrouping based on the UE ID and UEs with subgrouping assigned by the CN).

[0058] First example single - level sub - grouping

[0059] The first example is specifically illustrated in Figure 7 as shown in Figure 7 As shown, the paging UE subgroup ID space 700 is bifurcated into partitions 702 and 704. Partition 702 contains UE paging subgroups with subgroup IDs determined based on the UE ID, while partition 704 contains UE paging subgroups assigned by the CN. These two partitions form a single - level UE paging subgroup ID space 700, which contains, for example, consecutively numbered paging subgroup IDs. Although in the Figure 7 example, each partition is illustrated as containing three UE paging subgroups, the number of UE paging subgroups in each partition in the paging subgroup ID space is not limited to this and can be any other number.

[0060] In this first example, the UE can determine its paging subgroup ID in the following way. First, the RAN can be in Figure 6In step 602, broadcast the total number N of user subgroups based on UE ID configured and managed by the RAN sg (NumberofPagingGroup-UEID). Such information can be received by all UEs. A UE that supports the CN-assigned subgroup and has obtained the CN-assigned subgroup offset value from the CN can instead shift the CN-assigned paging subgroup ID offset by N sg , to derive its paging subgroup ID such that the derived paging subgroup ID falls within the higher CN-assigned partition 704 of the paging subgroup ID space 700 in Figure 7 . For example, a UE that supports the CN-assigned subgrouping and has obtained the CN-assigned subgroup offset value from the CN can derive its paging subgroup ID as:

[0061] Paging subgroup ID = CN-assigned subgroup offset + N sg , where, as described above, N sg represents the number of paging subgroups based on UE ID, as shown in 702 of Figure 7 , which occupies the lower value partition of the UE paging subgroup ID space 700.

[0062] In some cases of this first example, if the sum of the CN-assigned subgroup offset and N sg is greater than N max (in some embodiments, N max represents the maximum number of paging subgroups supported by the RAN, which can be configurable or hard-specified), then a UE that supports the CN-assigned subgrouping and has obtained the CN-assigned subgroup offset value from the CN can derive its paging subgroup ID as:

[0063] Paging subgroup ID = Mod(CN-assigned subgroup offset, N max -N sg )+N sg ,

[0064] where mod(a, b) represents the modulo operation that returns the remainder of a / b.

[0065] Essentially, in order for the paging subgroup ID partition 704 of the CN-assigned subgroup in the paging subgroup ID space 700 not to exceed the maximum total number of paging subgroups supported by the RAN after reserving N sg groups for the UE ID-based paging subgroups in partition 702, this example scheme limits the number of subgroups that a UE supporting the CN-assigned subgrouping can use to N max -N sg . This limited number of paging subgroup IDs is cyclically reused by the CN-assigned subgroup offset. In other words, in the CN-assigned partition 704, paging subgroup IDs can be assigned to entities that differ by N max -Nsg The offset assigned by CN gives the same paging subgroup ID.

[0066] In addition, for this first example single-level paging subgrouping mechanism, UEs that support subgrouping based on UE ID or for which no paging subgroup ID offset is provided by the CN can derive their paging subgroup ID as follows:

[0067] Paging subgroup ID = mod(floor(UE_ID / (N*N S )),N sg )

[0068] Where:

[0069] · UE_ID, as described above, represents the UE identifier determined using the UE network ID, such as a 5G-S-TMSI that cycles through a UEID space of a predefined size (e.g., 1024). In other words, UE_ID = mod(5G-S-TMSI, 1024).

[0070] · N, as described above, represents the total number of paging frames in the paging cycle T (e.g., the DRX paging cycle).

[0071] · N s , as described above, represents the predefined number of paging opportunities (POs) in a paging frame (PF).

[0072] · N sg , as described above, represents the total number of paging subgroups based on UE ID.

[0073] Essentially, UEs that support subgrouping based on UE ID are divided into N sg paging subgroups. The subgroup IDs of these N sg paging subgroups occupy the lower partition 702 of the single-level subgroup ID space 700. The UEs are interleaved into these N Figure 7 subgroups based on their UE_ID. In other words, UEs with UE_IDs that differ by N*N sg belong to the same paging subgroup, where N*N S represents the total number of POs in the paging cycle. S

[0074] Second example single-level subgrouping

[0075] The second example above is specifically illustrated in Figure 8 As Figure 8As shown, the paging UE subgroup ID space 800 is bifurcated into partitions 802 and 804. The partition 804 with higher paging subgroup IDs contains UE paging subgroups with IDs determined based on the UE ID, while the partition 802 with lower paging subgroup IDs contains UE paging subgroups assigned by the CN. These two partitions form a single-level UE paging subgroup ID space 800, which contains, for example, consecutively numbered paging subgroup IDs. Although in Figure 8 the example of

[0076] each partition is illustrated as containing three UE paging subgroups, the number of UE paging subgroups in each partition in the paging subgroup ID space is not limited to this and can be any other number. Figure 6 In this second example, the UE can determine its paging subgroup ID in the following manner. First, the RAN can broadcast the total number N sg (NumberofPagingSubgroup - UEID) of user subgroups based on the UE ID configured and managed by the RAN in step 602 of Figure 8 such information can be received by all UEs. UEs that support CN - assigned subgroups and have been assigned a subgroup ID by the CN can simply use the subgroup ID assigned by the CN as their actual paging subgroup ID, as shown in

[0077] Paging subgroup ID = CN - assigned paging subgroup ID.

[0078] In some cases of this second example, if the sum of the number of CN - assigned subgroups and N sg is greater than the maximum number N max of paging subgroups supported by the RAN, then UEs that support CN - assigned subgroups and have been assigned a subgroup ID by the CN can derive their paging group ID as:

[0079] Paging subgroup ID = mod(CN - assigned subgroup ID, N max - N sg ).

[0080] Essentially, in order for the paging subgroup ID partitions 802 and 804 not to exceed the maximum total number of paging subgroups supported by the RAN after reserving N sg subgroups for the paging subgroups based on the UE ID in partition 804, this example scheme limits the number of subgroups that UEs that support CN - assigned subgroups and have already been assigned a subgroup ID can use to N max - N sg . This limited number of paging subgroup IDs is cyclically reused by the CN - assigned subgroup IDs as the actual paging subgroup IDs of the CN - assigned paging subgroups. In other words, in Figure 8Within the partition 802 allocated by CN, it is possible to have a difference of N max -N sg The CN-allocated IDs are given the same paging subgroup ID.

[0081] In some variations of this exemplary embodiment, the number N of paging subgroups allocated by CN CN can be predetermined, and the UEs that support the sub-packets allocated by CN and are allocated a subgroup ID by CN can, in the following manner, based on the subgroup ID allocated by CN, cyclically reuse N CN correspondingly derive their actual paging subgroup ID:

[0082] Paging subgroup ID = mod(CN-allocated subgroup ID, N CN ).

[0083] In this second example, the UEs that support sub-packeting based on UE ID and / or are not allocated a paging subgroup ID by CN can derive their actual subgroup ID according to the following manner:

[0084] Paging subgroup ID = mod(floor(UE_ID / (N * N s ), N sg ) + N CN

[0085] Essentially, for this second example, the UEs that support sub-packeting based on UE ID and are not allocated a subgroup ID by CN are divided into N sg paging subgroups. These N sg subgroup IDs of the paging subgroups occupy Figure 8 the higher partition 804 of the single-level subgroup ID space 800. These UEs are interleaved and distributed into these N sg subgroups based on their UE_ID. In other words, UEs with a difference in UE_ID of N * N S belong to the same paging subgroup, where N * N S represents the total number of POs within the paging cycle. The actual paging subgroup ID of the UEs that support sub-packeting based on UE ID and are not allocated a subgroup ID by CN is further shifted up by N CN into the higher partition 804 of the single-level paging subgroup ID space 800, as specified in the example formula above.

[0086] In the various example single-level paging subgroup grouping schemes above, the CN-allocated subgroup ID offset is allocated and is thus known to the CN. The UE_ID is also known to the CN. Therefore, the CN can derive the actual paging subgroup ID of a specific UE according to a similar scheme as described above.

[0087] The paging subgroup ID determination formulas or algorithms of the above various examples are only for illustrative purposes. Other formulas can be used to determine the subgroup ID. The basic idea above is to divide the subgroup ID space into multiple partitions or sections, each partition or section for a subgroup ID based on UE ID or CN assignment rather than both. The actual subgroup ID of the UE does not need to be a direct value of any of the above formulas or other deterministic formulas. For example, additional mapping can be used to convert the value calculated from a specific formula above or other formulas into an actual subgroup name.

[0088] Multi - level Sub - grouping

[0089] In some other exemplary embodiments, a multi-level sub-grouping scheme can be designed, where a subgroup ID data structure is used to specify the paging subgroup. Each group ID data structure can contain one or more of multiple types of paging subgroup identifier data items that jointly specify the paging subgroup. In particular, a two-level subgroup ID data structure can contain one or more of two subgroup ID identification data items that jointly and uniquely specify the paging subgroup. The first identification data item can be referred to as the subgroup set ID (for identifying a set of paging subgroups), while the second identification data item can be referred to as the subgroup ID (which represents the identification within the subgroup set). The actual two-level subgroup ID data structure can include one of the two identification data items or both, as further described in detail in the examples below.

[0090] First exemplary two-level sub-grouping

[0091] In the first exemplary two-level sub-grouping scheme and for the RAN, the subgroup set ID of the UE's subgroup ID data structure can be directly assigned by the CN, while the subgroup ID of the UE's subgroup ID data structure can be calculated using the UE_ID, as Figure 9 shown in

[0092] The subgroup ID data of the subgroup ID data structure can be derived, for example, as follows:

[0093] subgroup ID = mod(floor(UE_ID / (N*N S )),N sg )

[0094] For Figure 9 subgroup set #0 and subgroup set #1 in Figure 9 the CN assignments of the subgroup set ID data items are shown as 902 and 904. Although Figure 9 only two subgroup sets are illustrated, the actual implementation is not limited to this. Any number of subgroup sets can be assigned by the CN in this scheme. The subgroup ID data items within subgroup ID set #0 are shown as 910, 912, and 914 in Figure 9 while the subgroup ID data items within subgroup ID set #1 are inFigure 9 are shown as 920, 922, and 924 in

[0095] In this example embodiment, for a particular UE, its subgroup ID data structure may contain one or both of the above subgroup ID data items in the following manner:

[0096] · The subgroup ID data structure of a UE that supports subgrouping based on UE ID and is not provided with a subgroup set ID assigned by the CN may contain only the subgroup ID data item based on UE ID determined according to the above formula.

[0097] · The subgroup ID data structure of a UE assigned a subgroup set ID by the CN and also supporting subgrouping based on UE ID may contain both the subgroup set ID assigned by the CN and the subgroup ID data item obtained according to the above equation.

[0098] · The subgroup ID data structure of a UE assigned a subgroup set ID by the CN but not supporting subgrouping based on UE ID may include only the subgroup set ID assigned by the CN.

[0099] Second Example Two-Level Subgrouping

[0100] In the second example two-level subgrouping scheme and for the RAN, the subgroup set ID of the subgroup ID data structure of a UE may be derived from the UE_ID, while the subgroup ID of the subgroup ID data structure of the UE may be assigned by the CN and obtained from the CN, as Figure 10 shown. The subgroup set ID may be calculated, for example, as:

[0101] subgroup set ID = mod(floor(UE_ID / (N * N S ))), N sg ).

[0102] For Figure 10 subgroup set #0 and subgroup set #1 in Figure 10 , the subgroup set ID data items calculated according to the above equation are illustrated as 1002 and 1004. Although Figure 10 only two subgroup sets are illustrated, the actual implementation is not limited thereto. There may be any number of subgroup sets supported by the RAN (such as N sg ). The subgroup ID data items assigned by the CN within subgroup ID set #0 are shown as 1010, 1012, and 1014 in Figure 10 , while the subgroup ID data items within subgroup ID set #1 are shown as 1020, 1022, and 1024 in Figure 10 .

[0103] In this example embodiment, for a specific UE, its subgroup ID data structure may include one or both of the above subgroup ID data items in the following manner:

[0104] · The subgroup ID data structure of a UE that supports subgrouping based on UE ID and / or the set of subgroup IDs not assigned by the CN may only include the set of subgroup IDs based on UE ID determined using the above equation.

[0105] · The subgroup ID data structure of a UE assigned a subgroup ID by the CN and also supporting subgrouping based on UE ID may include both the subgroup ID assigned by the CN and the set of subgroup IDs determined using the above equation.

[0106] · The subgroup ID data structure of a UE assigned a subgroup ID by the CN but not supporting subgrouping based on UE ID may only include the subgroup ID assigned by the CN.

[0107] Signaling

[0108] Returning to Figure 6 the logical flow 600 of, and in step 602, in some example embodiments, the subgrouping policy and subgroup information broadcast or sent from the network side may be carried via a system information block, including one or more of the following fields or data items.

[0109] For example, the system information block may include a first flag that may be enabled to explicitly indicate that subgrouping based on UE ID is available for the serving cell. The first flag and other supplementary information items in the system information block may include one or more of the following:

[0110] · Nsg: The maximum number of paging subgroups based on UE ID supported in the serving cell.

[0111] · Nsg_set: The maximum number of sets of paging subgroups based on UE ID supported in the serving cell.

[0112] · UEIDPagingSubgrouping: Indicates whether the serving cell supports subgrouping based on UE ID.

[0113] · DCIFormat: Indicates the DCI format that supports subgrouping based on UE ID.

[0114] Again, for example, the system information block may include a second flag that may be enabled to explicitly indicate that the subgrouping assigned by the CN is available for the serving cell. The second flag and other supplementary information items in the system information block may include one or more of the following:

[0115] ·SupportCNassignedSubgroup: Indicates whether the serving cell supports CN-assigned subgroups.

[0116] ·Ncn: The maximum number of paging subgroups with CN assignment supported in the serving cell.

[0117] ·Ncn_set: The maximum number of UE ID-based paging subgroup sets supported in the serving cell.

[0118] ·DCIFormat: Indicates the DCI format that supports CN-assigned subgroups.

[0119] For another example, the system information block may include some indications that can be enabled to implicitly indicate that CN-assigned subgroups are available for the serving cell. In some embodiments, if N max -Nsg is greater than zero, it means that CN-assigned subgroups are supported, and the value of (N max -N sg ) represents the total number of CN-assigned subgroups.

[0120] In some embodiments, the access network may be implemented as a combination of a central and distributed unit system (i.e., CU-DU separation) that communicates via the F1 interface. To generate paging information, signaling regarding paging subgroup information between the DU and the CU may be performed before the PO. Such signaling information may include, for example, one or more of subgroup ID information, subgroup set ID information, and / or subgroup ID offset values (CN-assigned).

[0121] The above description and the drawings provide specific example embodiments and implementations. However, the described subject matter may be implemented in various different forms, and thus the subject matter covered or claimed is intended to be construed as not limited to any of the example embodiments set forth herein. The intended scope of the subject matter claimed or covered is quite broad. In addition, for example, the subject matter may be implemented as a method, device, component, system, or non-transitory computer-readable medium for storing computer code. Thus, the embodiments may take, for example, the form of hardware, software, firmware, a storage medium, or any combination thereof. For example, the above method embodiments may be implemented by a component, device, or system including a memory and a processor by executing computer code stored in the memory.

[0122] Throughout the specification and claims, terms may have nuanced meanings suggested or implied in context beyond their explicitly stated meanings. Similarly, as used herein, the phrase "in one embodiment / implementation" does not necessarily refer to the same embodiment, and the phrase "in another embodiment / implementation" does not necessarily refer to a different embodiment. For example, the claimed subject matter is intended to include combinations of all or part of the example embodiments.

[0123] Generally speaking, terms can be understood at least in part based on their use in context. For example, terms such as "and," "or," or "and / or" as used herein can include a variety of meanings that can depend at least in part on the context in which these terms are used. Generally, "or" when used to relate a list such as A, B, or C is intended to mean A, B, and C (used herein in an inclusive sense) as well as A, B, or C (used herein in an exclusive sense). Additionally, as used herein, depending at least in part on the context, the term "one or more" can be used to describe any feature, structure, or characteristic in a singular sense or can be used to describe a combination of features, structures, or characteristics in a plural sense. Similarly, terms such as "a," "an," or "the" can be understood to convey either a singular usage or to express a plural usage, at least in part depending on the context. Additionally, the term "based on" can be understood to not necessarily be intended to convey a set of exclusive factors, but can allow for the existence of additional factors that are not necessarily explicitly described, again, at least in part depending on the context.

[0124] References throughout this specification to features, advantages, or similar language do not mean that all features and advantages that can be achieved with the present solution should or are included in any single embodiment. Rather, language referring to features and advantages should be understood to mean that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present solution. Thus, the discussion of features and advantages throughout this specification and similar language can, but does not necessarily, refer to the same embodiment.

[0125] Furthermore, the described features, advantages, and characteristics of the present solution can be combined in any suitable manner in one or more embodiments. Based on the description herein, one of ordinary skill in the relevant art will recognize that the present solution can be practiced without one or more specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not exist in all embodiments of the present solution.

Claims

1. A method performed by a wireless terminal device, comprising: Receive paging subgroup configuration information from a wireless network; Determine a paging subgroup identifier based on the paging subgroup configuration information; And Determine whether to wake up to monitor the paging occasion based on whether the paging subgroup identifier corresponding to the paging occasion is indicated in a downlink control information (DCI) message before the paging occasion arrives, Wherein the paging subgroup identifier indicates a paging subgroup in a first type of paging subgroup or another paging subgroup in a second type of paging subgroup; Wherein a first paging subgroup identifier corresponding to the first type of paging subgroup is assigned by a core network, and a second paging subgroup identifier corresponding to the second type of paging subgroup is generated based on a UE identifier (UEID); And Wherein the first paging subgroup identifier and the second paging subgroup identifier are consecutively numbered, and the second paging subgroup identifier is greater than the first paging subgroup identifier.

2. The method according to claim 1, wherein the second paging subgroup identifier is further generated based on the number of total paging frames in a DRX paging cycle, a predefined number of paging opportunities (POs) in a paging frame, the number of second - type paging subgroups, and the number of first - type paging subgroups.

3. The method according to claim 2, wherein the second paging subgroup identifier is generated according to mod(floor(UE_ID / (N*N s )),N sg )+N CN where: UE_ID is the UE identifier; N is the number of total paging frames in a DRX paging cycle; N s is the predefined number of paging occasions (POs) in a paging frame; N sg is the number of the second type of paging subgroups; and N CN is the number of paging subgroups of the first type.

4. The method according to claim 1, wherein the total number of the first - type paging subgroups and the second - type paging subgroups is N max , the total number of the first - type paging subgroups is N CN , the total number of the second - type paging subgroups is N sg , and wherein N CN = N max - N sg .

5. The method according to claim 4, further comprising: In response to N max -N sg being greater than zero, the first type of paging subgroup is determined to be available by the wireless terminal device.

6. The method according to claim 2, wherein the paging subgroup configuration information is received via a system information block and at least includes the number of the second - type paging subgroups.

7. The method according to claim 1, wherein: The DCI message includes a bitmap; Each bit of the bitmap corresponds to a paging subgroup; And A value of a bit corresponding to the paging subgroup identifier of the wireless terminal device is set to 1, indicating that the wireless terminal device will wake up to monitor the paging occasion.

8. A method performed by a wireless terminal device, comprising: Receive paging subgroup configuration information from a wireless network; Determine a paging subgroup identifier based on the paging subgroup configuration information; And Determine whether to wake up to monitor the paging occasion based on whether the paging subgroup identifier corresponding to the paging occasion is indicated in a downlink control information (DCI) message before the paging occasion arrives, Wherein the paging subgroup identifier indicates a paging subgroup in a first type of paging subgroup or another paging subgroup in a second type of paging subgroup; The first paging subgroup identifier corresponding to the first type of paging subgroup is allocated by the core network, and the second paging subgroup identifier corresponding to the second type of paging subgroup is generated based on the UE identifier (UEID) according to mod(floor(UE_ID / (N*N s )),N sg )+N CN , Wherein: UE_ID is the UE identifier; N is the number of total paging frames in a DRX paging cycle; N s is the predefined number of paging occasions (POs) in a paging frame; N sg is the number of the second type of paging subgroups; and N CN is the number of paging subgroups of the first type.

9. The method according to claim 8, wherein the total number of the first type of paging subgroups and the second type of paging subgroups is N max , the total number of the first type of paging subgroups is N CN , the total number of the second type of paging subgroups is N sg , and wherein N CN = N max - N sg .

10. The method according to claim 9, further comprising: In response to N max -N sg being greater than zero, the first type of paging subgroup is determined to be available by the wireless terminal device.

11. The method according to claim 8, wherein the paging subgroup configuration information is received via a system information block and at least includes the number of the second type of paging subgroups.

12. The method according to claim 8, wherein: The DCI message includes a bitmap, and each bit of the bitmap corresponds to a paging subgroup; And A value of a bit corresponding to the paging subgroup identifier of the wireless terminal device is set to 1, indicating that the wireless terminal device will wake up to monitor the paging occasion.

13. A wireless terminal device, comprising a memory and at least one processor, the memory for storing instructions, the at least one processor being configured to execute the instructions to: Receive paging subgroup configuration information from a wireless network; Determine a paging subgroup identifier based on the paging subgroup configuration information; And Determine whether to wake up to monitor the paging occasion based on whether the paging subgroup identifier corresponding to the paging occasion is indicated in a downlink control information (DCI) message before the paging occasion arrives, Wherein the paging subgroup identifier indicates a paging subgroup in a first type of paging subgroup or another paging subgroup in a second type of paging subgroup; Wherein a first paging subgroup identifier corresponding to the first type of paging subgroup is assigned by a core network, and a second paging subgroup identifier corresponding to the second type of paging subgroup is generated based on a UE identifier (UEID); And Wherein the first paging subgroup identifier and the second paging subgroup identifier are consecutively numbered, and the second paging subgroup identifier is greater than the first paging subgroup identifier.

14. The wireless terminal device according to claim 13, wherein the second paging subgroup identifier is further generated based on the number of total paging frames in a DRX paging cycle, a predefined number of paging opportunities (POs) in a paging frame, the number of second-type paging subgroups, and the number of first-type paging subgroups.

15. The wireless terminal device according to claim 14, wherein the second paging subgroup identifier is generated according to mod(floor(UE_ID / (N*N s )),N sg )+N CN where: where: UE_ID is the UE identifier; N is the number of total paging frames in a DRX paging cycle; N s is the predefined number of paging occasions (POs) in a paging frame; N sg is the number of paging subgroups of the second type; and N CN is the number of paging subgroups of the first type.

16. The wireless terminal device according to claim 13, wherein the total number of the first-type paging subgroups and the second-type paging subgroups is N max , the total number of the first-type paging subgroups is N CN , the total number of the second-type paging subgroups is N sg , and where N CN =N max -N sg .

17. The wireless terminal device according to claim 16, further comprising: In response to N max -N sg Greater than zero, the first type of paging subgroup is determined to be available by the wireless terminal device.

18. The wireless terminal device according to claim 14, wherein the paging subgroup configuration information is received via a system information block and at least includes the number of the second-type paging subgroups.

19. The wireless terminal device according to claim 13, wherein: The DCI message includes a bitmap; Each bit of the bitmap corresponds to a paging subgroup; And The value of the bit corresponding to the paging subgroup identifier of the wireless terminal device is set to 1, indicating that the wireless terminal device will wake up to monitor the paging occasion.

20. A wireless terminal device, comprising a memory and at least one processor, the memory for storing instructions, the at least one processor configured to execute the instructions to: receive paging subgroup configuration information from a wireless network; determine a paging subgroup identifier based on the paging subgroup configuration information; and Determine whether to wake up to monitor the paging occasion based on whether the paging subgroup identifier corresponding to the paging occasion is indicated in a downlink control information (DCI) message before the paging occasion arrives. wherein the paging subgroup identifier indicates a paging subgroup in a first type of paging subgroup or another paging subgroup in a second type of paging subgroup; wherein a first paging subgroup identifier corresponding to the first type of paging subgroup is assigned by a core network, and a second paging subgroup identifier corresponding to the second type of paging subgroup is generated based on a user equipment identifier (UEID) according to mod(floor(UE_ID / (N*N s )),N sg )+N CN 、based on the UE identifier (UEID); wherein: UE_ID is the UE identifier; N is the number of total paging frames in the DRX paging cycle; N s is the predefined number of paging occasions (POs) in a paging frame; N sg is the number of paging subgroups of the second type; and N CN is the number of paging subgroups of the first type.

21. The wireless terminal device according to claim 20, wherein: The total number of the first type of paging subgroups and the second type of paging subgroups is N max , the total number of the first type of paging subgroups is N CN , the total number of the second type of paging subgroups is N sg , and among them N CN = N max - N sg .

22. The wireless terminal device according to claim 21, wherein the at least one processor is further configured to execute the instructions to: in response to N max -N sg being greater than zero, determine by the wireless terminal device that the first type of paging subgroup is available.

23. The wireless terminal device according to claim 20, wherein: The paging subgroup configuration information is received via the system information block and at least includes the number of the second type of paging subgroups.

24. The wireless terminal device according to claim 20, wherein: The DCI message includes a bitmap, and each bit of the bitmap corresponds to a paging subgroup; and The value of the bit corresponding to the paging subgroup identifier of the wireless terminal device is set to 1, indicating that the wireless terminal device will wake up to monitor the paging occasion.

25. A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

26. A computer program product, comprising a computer program / instruction, characterized in that When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

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