Patent Application
20240121755
This disclosure is directed generally to wireless communication network technologies and particularly to paging configuration and power saving in wireless terminal devices.
In a wireless communication system, a paging mechanism may be employed to initiate an active communication between a wireless access network node and a wireless terminal device that is otherwise in an idle state. The frequency in which a wireless terminal device wakes up from its idle state to check for paging information directly impacts power consumption and battery drain of the terminal device. It is thus desirable to reduce a rate of false paging alarm situations where the wireless terminal device wakes up to monitor a paging information but only to find out that it is not targeted.
This disclosure relates to paging configuration and power saving in wireless terminal devices.
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 a 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 prior to an arrival of the paging occasion.
In another embodiment, a method performed by a wireless 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 separate divisions of a two-division paging subgroup identifier space. The method may further include transmitting a signaling message prior to the paging occasion to: indicate to the wireless terminal device that the paging subgroup identifier is activated among other paging subgroup identifiers and cause the wireless terminal device to wake up to monitor the paging occasion.
In another embodiment, a wireless terminal device or access network node comprising a processor and a memory is disclosed. The processor may be configured to read computer code from the memory to implement any of the methods above.
In yet another embodiment, a computer program product comprising a non-transitory computer-readable program medium with computer code stored thereupon is disclosed. The computer code, when executed by a processor, may cause the processor to implement any one of the methods above.
The above embodiments and other aspects and alternatives of their implementations are described in greater detail in the drawings, the descriptions, and the claims below.
The technology and examples of implementations and/or embodiments described in this disclosure can be used to reduce power consumption of wireless terminal devices utilizing 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, implementation, or embodiment. Section headers are used in the present disclosure to facilitate understanding of the disclosed implementations and are not intended to limit the disclosed technology in each of the sections only to the corresponding section. The disclosed implementations may be further embodied in a variety of different forms and, therefore, the scope of this disclosure or claimed subject matter is intended to be construed as not being limited to any of the embodiments set forth below. The various implementations may be embodied as methods, devices, components, systems, products, or non-transitory computer readable media. Accordingly, embodiments of this disclosure may, for example, take the form of hardware, software, firmware or any combination thereof.
This disclosure is directed to methods, systems, and devices related to wireless access networks, and more specifically, to implementations that facilitate reduction of power consumption in wireless terminal devices that receives services form a wireless network when being paged. While this disclosure provides example implementations in some particular generations of cellular network system, the underlying principles are applicable to other generations of cellular network systems and other general non-cellular wireless network systems.
An example wireless communication network, shown as 100 in
In the wireless communication network 100 of
Similarly, the WANN 120 may include a base station or other wireless network access point capable of communicating wirelessly via the over-the-air interface 204 with one or more UEs and communicating with the core network 130. For example, the WANN 120 may be implemented, without being limited, in the form of a 2G base station, a 3G nodeB, an LTE eNB, a 4G LTE base station, a 5G NR base station, a 5G central-unit base station, or a 5G distributed-unit base station. Each type of these WANNs may be configured to perform a corresponding set of wireless network functions. The WANN 202 may include transceiver circuitry 214 coupled to one or more antennas 216, which may include an antenna tower 218 in various forms, to effectuate wireless communications with the UEs 110 and 112. The transceiver circuitry 214 may be coupled to one or more processors 220, which may further be coupled to a memory 222 or other storage devices. The memory 222 may be transitory or non-transitory and may store therein instructions or code that, when read and executed by the processor 220, cause the processor 220 to implement various functions of the WANN 120 described herein.
The wireless transmission resources for the over-the-air interface 204 include frequency, time, and spatial resource. For example, the available frequency and time resource available for wireless communication (alternatively referred to as wireless resource, or wireless transmission resource) is illustrated as 300 in
The division of time and frequency of wireless resource 300 may be made at various hierarchical levels.
While the description above focuses on time and frequency resource 300, it may be combined with spatial multiplexing based on utilizing multiple antennas and beam forming in wireless transmission. The allocation and configuration of such spatial resources may be part of the overall wireless resource allocation and configuration. The principles underlying the various implementations included in this disclosure are intended to be applicable to wireless resource allocation and configuration including all of time, frequency, and space dimensions. The wireless resource descried above may be configured or allocated for various paging functions as described below.
In the wireless communication system 100 of
For example, the carrier network 102 of
Some specific implementations of the example paging mechanism above may be based on Discontinuous Reception (DRX). In DRX, monitoring of paging configuration information and corresponding paging information by the UEs may be managed in cycles, referred to as DRX cycles, or paging cycles. The paging configuration information may be carried in paging Downlink Control Information (DCI) message. The paging information identified by the paging configuration information may be contained in a paging message.
After waking up to monitor and receive the paging DCI 412, the UE may further receive the paging message 414 according to the network resource configuration and scheduling information contained in the paging DCI 412. The paging message 414, for example, may be carried on a physical downlink shared channel (PDSCH). The paging message may target a particular UE. An identification of the particular target UE may be included in the paging message. An example of such identification of the target UE in a 5th generation wireless cellular network may be implemented as a 5th Generation System Temporary Mobile Subscription Identifier (5G-S-TMSI). The UE may process the received paging message 414 and determine whether it is targeted by 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, it further processes the paging message and respond to the paging message. Otherwise it falls back to sleep state and wait for waking up again at its next PO (or paging DCI).
There may be multiple paging requests targeting various UEs during a paging cycle 410. In accommodation, and as shown in
With the paging configuration of
In some further implementations, each group of UEs that are configured to monitor a same PO may be divided into subgroups to further facilitate power saving. For example, once the UEs are divided into subgroups, the network may, prior to transmitting the PO corresponding to the UE group, additionally transmit an signaling message to indicate subgroup(s) to which the paged UE(s) in the PO belongs. The monitoring of such signaling message may only require minimal functional support at the UEs (e.g., the UEs in the UE group need not to fully wake up to monitor the signaling message). As such, only the subgroups of UEs within the UE group associated with the PO that are implicated by the signaling message need to wake up to receive the PO and paging message, thereby further reducing power consumption for the UEs outside the implicated (or activated) subgroup.
Various manners in which a UE paging group may be divided into subgroups for paging purposes are described in more detail below. In some implementations, the UEs may be sub-grouped based on their network identifiers, referred to as UE IDs in the disclosure herein. For example, in a UE ID-based subgrouping, a subgroup identifier for a UE paging subgroup with a UE paging group that a particular UE belongs to may be calculated based on, for example, the 5G-S-TMSI of the UE. One of any various predetermined optional algorithms known to both the wireless access network node and the UEs may be selected for use in uniquely converting a UE identifier into a paging subgroup identifier.
In some other implementations, subgrouping of the UEs may be determined by the core network (CN) 130 of
In some implementations, each RAN (or the wireless access network node therein) may be responsible for determining a maximum number of UE ID based paging subgroups (based on, e.g., the capability of the RAN), represented by Nsg, while the CN may be responsible for determining a maximum number of UE paging subgroups that are assigned by the CN, represented by NCN.
In general, the UE ID-based UE subgrouping may be considered somewhat random since the UE IDs generally may not carry much information with respect to UE paging probability. On the other hand, the CN-based UE subgrouping may be more based on UE characteristics such as paging probability. As such, the CN-based UE subgrouping may carry the advantage of subgrouping similar UEs together in terms of network characteristics relevant to paging such as paging probability.
In some implementations, both UE ID-based UE subgrouping and CN-based UE subgrouping may be supported for a RAN. In such implementations, a total number of UE ID-based UE subgroups and CN-based UE subgroups may be limited to a maximum number of UE subgroups with a UE group, represented by Nmax. In some implementations, some UEs may only support UE ID-based subgrouping or may not be assigned with a subgroup ID by the CN, whereas other UEs may be capable of accepting subgroup assignment from the CN in addition or alternative to supporting UE ID-based subgrouping.
In implementations of UE paging subgrouping based on both UE-ID and CN assignment, it is likely that the CN may assign some UEs to a paging subgroup that may also contain some other UEs that happen to fall within the subgroup because of their UE-IDs for one RAN. A UE subgroup corresponding to a particular UE subgroup identifier may consequently contain both CN-assigned UEs and UEs of random UE-IDs. In other words, while the CN assignment of UE into a particular subgroup may aim at having similar UEs in the particular subgroup (in terms of, for example, UE paging probability), the actual UE subgroup may end up with UEs having drastically different paging probabilities. In such implementations, the UEs having lower paging probabilities in a paging subgroup having mixed paging probabilities would suffer higher false alarm ratio and undesired power consumption and battery drain.
In addition, because the core network may manage RAN with distinct capabilities and UEs may frequently move between tracking areas of various RANs, it is likely that the CN may need to perform an overall UE subgroup assignment for UEs that support CN-based subgrouping. The number of UE subgroups that can be assigned by the CN thus may be larger than the maximum number of UE paging subgroups that can be supported by and as determined by some particular RAN having lower capabilities.
The various further implementations described below for paging subgroup identifier determination for either or both of UE-ID based subgrouping and/or CN-based subgrouping are designed to provide schemes that attribute similar UEs (in terms of, for example, paging probability) with unique paging subgroup identification. Such paging subgroup identification may be implemented in either a single-level or multi-level grouping scheme. The disclosed schemes result in higher likelihood that UEs having similar paging characteristics as determined by the CN are sub-grouped together under particular subgroup identification and without 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.
The message used in Step (a) may be implemented as various types of control message. For example, it may be implemented as a DCI message. Such a DCI message may carry information about the paging subgroups within a paging group that may need to wake up to receive a corresponding PO. Such information, for example, may be included as:
In some example implementations, a single-level subgrouping scheme may be used in which each subgroup ID contains a single identification value in a paging subgroup ID space. For example, all paging subgroups may be numbered consecutively with corresponding subgroup ID. In such a single-level subgrouping scheme, the UE ID-based paging subgroups and the CN-assigned paging subgroups may be separated rather than mixed. For example, a single-level paging subgroup ID space may be bifurcated or divided into two separate divisions, one for UE ID-based subgroups and the other for CN assigned subgroups.
In a first example, the UE ID-based subgroups may form a division of paging UE subgroups that are lower in ID number than the division formed by CN-assigned UE paging subgroups in the single-level paging subgroup ID space. In a second example, the UE ID-based subgroups may form a division of paging UE subgroups that are larger in ID number than the division formed by the CN-assigned UE paging subgroups in the single-level paging subgroup ID space. In some other examples, the two paging subgroup ID divisions may be interleaved or arranged in other predefined pattern rather than bifurcated in the single-level paging subgroup ID space, as long as they do not mix (i.e., each division may be distributed as multiple parts the paging subgroup ID space, and each part of a division do not contains subgroup IDs of both UEs that only support UE ID-based subgrouping and UEs that only support CN-assigned subgrouping).
The first example is specifically illustrated in
In this first example, a UE may determine its paging subgroup ID in the following manner First, the RAN may broadcast in step 602 of
Paging Subgroup ID=CN-assigned Subgroup Offset+Nsg,
where, as described above, Nsg represents the number of UE ID-based paging subgroups, which occupies, as shown by 702 of
In some situations of this first example, if the sum of CN-assigned subgroup offset and Nsg is greater than Nmax (in some implementation, Nmax represents the maximum number of paging subgroups supported by the RAN which may be either configurable or hard specified), a UE that supports CN-assigned subgrouping and have obtained a value of the CN-assigned subgroup offset from CN may derive its paging subgroup ID as:
Paging Subgroup ID=Mod(CN-assigned Subgroup offset,Nmax−Nsg)+Nsg,
where the mod(a, b) represents the modulo operation that returns a remainder of a/b.
Essentially, in order for the paging subgroup ID division 704 for the CN-assigned subgroups in the paging subgroup ID space 700 to not overrun the maximum total number of paging subgroups supported by the RAN after Nsg groups are reserved in the division 702 for UE ID-based paging subgroups, this example scheme limits the number of subgroups that could be used by the UEs supporting CN-assigned subgrouping to Nmax−Nsg. This limited number of paging subgroup IDs are cyclically reused by the CN-assigned subgroup offsets. In other words, CN-assigned offsets that differ by Nmax−Nsg may be given a same paging subgroup ID in the CN-assigned division 704.
Further for this first example single-level paging subgrouping mechanism, a UE that supports UE ID-based subgrouping or that is not provided with an CN-assigned paging subgroup ID offset may derive its paging subgroup ID as follows:
Paging Subgroup ID=mod(floor(UE_ID/(N*NS)),Nsg)
where:
Essentially, the UEs supporting UE ID-based subgrouping are divided into Nsg paging subgroups. Subgroup IDs of these Nsg paging subgroups occupy the lower division 702 of the single-level subgroup ID space 700 of
The second example above is specifically illustrated in
In this second example, a UE may determine its paging subgroup ID in the following manner First, the RAN may broadcast in step 602 of
Paging Subgroup ID=CN-assigned Paging Subgroup ID.
In some situations of this second example, if the sum of a number of CN-assigned subgroups and Nsg is greater than Nmax the maximum number of paging subgroups supported by the RAN, a UE that supports CN-assigned subgrouping and assigned with a subgroup ID by the CN may derive its paging group ID as:
Paging Subgroup ID=mod(CN-assigned Subgroup ID,Nmax−Nsg).
Essentially, in order for the paging subgroup ID divisions 802 and 804 to not overrun the maximum total number of paging subgroups supported by the RAN after Nsg subgroups are reserved in the division 804 for UE ID-based paging subgroups, this example scheme limits the number of subgroups that could be used by the UEs supporting CN-assigned subgrouping and have been assigned with subgroup IDs to Nmax−Nsg. The limited number of paging subgroup IDs are cyclically reused by the CN-assigned subgroup IDs as the actual paging subgroup IDs for CN-assigned paging subgroups. In other words, CN-assigned IDs that differ by Nmax−Nsg may be given a same paging subgroup ID within the CN-assigned division 802 of
In some variation of this example implementation, a number of CN-assigned paging subgroups, NCN, may be predetermined and a UE that supports CN-assigned subgrouping and are assigned with subgroup IDs by the CN may correspondingly derive its actual paging subgroup ID by cyclically reusing NCN according to the CN-assigned subgroup IDs in a manner described by:
Paging Subgroup ID=mod(CN-assigned Subgroup ID,NCN).
In this second example, a UE that supports UE ID-based subgrouping and/or that is not assigned with a paging subgroup ID by the CN may derive its actual subgroup ID according to:
Paging Subgroup ID=mod(floor(UE_ID/(N*NS)),Nsg)+NCN
Essentially for this second example, the UEs supporting UE ID-based subgrouping and not assigned with a subgroup ID by CN are divided into Nsg paging subgroups. Subgroup IDs of these Nsg paging subgroups occupy the higher division 804 of the single-level subgroup ID space 800 of
In the various example single-level paging subgroup grouping schemes above, CN-assigned subgroup ID offset is assigned and thus known to the CN. The UE_ID is further known to the CN. The CN may thus derive an actual paging subgroup ID for the particular UE following the similar schemes above.
The paging subgroup ID determination formula or algorithm for the various examples above are merely illustrated as examples. Other formula may be used to determine the subgroup IDs. The essential idea above is to separate the subgroup ID space into divisions or parts, each division or part is used for subgroup IDs that are based either on UE IDs or CN-assignment, but not both. The actual subgroup IDs for the UEs need not be the direct values of any of the formula above or other deterministic formula. For example, additional mapping may be used to convert values calculated from a particular formula above or other formulae to actual subgroup designations.
In some other example implementations, a multilevel subgrouping scheme may be designed in which a subgroup ID data structure is used to specify paging subgroups. Each group ID data structure may contain one or more of multiple types of paging subgroup identification data items that jointly specify a paging subgroup. Particularly, a two-level subgroup ID data structure may contain one or more of two subgroup ID identification data items that jointly and uniquely specifies a paging subgroup. The first identification data item may be referred to as subgroup set ID (for identifying sets of paging subgroups) whereas the second identification data item may be referred to as subgroup ID (which represents an identification within a subgroup set). An actual two-level subgroup ID data structure may include one of the two identification data items or both of the two identification data items, as described in further detail in the examples below.
In a first example two-level subgrouping scheme and for a RAN, the subgroup set ID of a subgroup ID data structure of a UE may be directly assigned by CN whereas the subgroup ID of the subgroup ID data structure of the UE may be calculated using the UE ID, as illustrated in
The subgroup ID data of the subgroup ID data structure, for example, may be derived as follow:
Subgroup ID=mod(floor(UE_ID/(N*NS)),Nsg)
The CN assignment of the subgroup set ID data items is shown as 902 and 904 for subgroup set #0 and subgroup set #1 in
In this example implementation, for a particular UE, its subgroup ID data structure may contain either one or both of the subgroup ID data items above in the following manner
In a second example two-level subgrouping scheme and for a RAN, the subgroup set ID of a subgroup ID data structure of a UE may be derived from the UE ID whereas the subgroup ID of the subgroup ID data structure of the UE may be assigned by and obtained from the CN, as illustrated in
Subgroup set ID=mod(floor(UE_ID/(N*NS)),Nsg).
The subgroup set ID data items that may be calculated following the equation above are illustrated as 1002 and 1004 for subgroup set #0 and subgroup set #1 in
In this example implementation, for a particular UE, its subgroup ID data structure may contain either one or both of the subgroup ID data items above in the following manner
Returning to the logic flow 600 of
For example, the system information block may include a first flag that may be enabled to explicitly indicate that the UE ID-based subgrouping is available for the serving cell. The first flag and other supplemental information items in the system information block may include one or more of:
For another example, the system information block may include a second flag that may be enabled to explicitly indicate that CN-assigned subgrouping is available for the serving cell. The second flag and other supplemental information items in the system information block may include one or more of:
For another example, the system information block may include some indications that may be enabled to implicitly indicate that CN-assigned subgrouping is available for the serving cell. In some implementations, if Nmax−Nsg is greater than zero, it means that the CN-assigned subgrouping is supported, and the value of (Nmax−Nsg) represents the total number of CN-assigned subgroups.
In some implementations, the access network may be implemented as a combination of central and distributed unit system (i.e., CU-DU split) communicating via an F1 interface. For generating the paging information, signaling between a DU and CU with respect to paging subgroup information before a PO may be performed. Such signaling information, for example, may include one or more of the subgroup ID information, subgroup set ID information, and/or subgroup ID offset value (CN-assigned).
The description and accompanying drawings above provide specific example embodiments and implementations. The described subject matter may, however, be embodied in a variety of different forms and, therefore, covered or claimed subject matter is intended to be construed as not being limited to any example embodiments set forth herein. A reasonably broad scope for claimed or covered subject matter is intended. Among other things, for example, subject matter may be embodied as methods, devices, components, systems, or non-transitory computer-readable media for storing computer codes. Accordingly, embodiments may, for example, take the form of hardware, software, firmware, storage media or any combination thereof. For example, the method embodiments described above may be implemented by components, devices, or systems including memory and processors by executing computer codes stored in the memory.
Throughout the specification and claims, terms may have nuanced meanings suggested or implied in context beyond an explicitly stated meaning. Likewise, the phrase “in one embodiment/implementation” as used herein does not necessarily refer to the same embodiment and the phrase “in another embodiment/implementation” as used herein does not necessarily refer to a different embodiment. It is intended, for example, that claimed subject matter includes combinations of example embodiments in whole or in part.
In general, terminology may be understood at least in part from usage in context. For example, terms, such as “and”, “or”, or “and/or,” as used herein may include a variety of meanings that may depend at least in part on the context in which such terms are used. Typically, “or” if used to associate a list, such as A, B or C, is intended to mean A, B, and C, here used in the inclusive sense, as well as A, B or C, here used in the exclusive sense. In addition, the term “one or more” as used herein, depending at least in part upon context, may be used to describe any feature, structure, or characteristic in a singular sense or may be used to describe combinations of features, structures or characteristics in a plural sense. Similarly, terms, such as “a,” “an,” or “the,” may be understood to convey a singular usage or to convey a plural usage, depending at least in part upon context. In addition, the term “based on” may be understood as not necessarily intended to convey an exclusive set of factors and may, instead, allow for existence of additional factors not necessarily expressly described, again, depending at least in part on context.
Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present solution should be or are included in any single implementation thereof. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present solution. Thus, discussions of the features and advantages, and similar language, throughout the specification may, but do not necessarily, refer to the same embodiment.
Furthermore, the described features, advantages and characteristics of the present solution may be combined in any suitable manner in one or more embodiments. One of ordinary skill in the relevant art will recognize, in light of the description herein, that the present solution can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the present solution.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2021/125327 | Oct 2021 | US |
| Child | 18541781 | US |
