Patent Description:
The following abbreviations are herewith defined, some of which are referred to within the following description: Third Generation Partnership Project (3GPP), European Telecommunications Standards Institute (ETSI), Frequency Division Duplex (FDD), Frequency Division Multiple Access (FDMA), Long Term Evolution (LTE), New Radio (NR), Very Large Scale Integration (VLSI), Random Access Memory (RAM), Read-Only Memory (ROM), Erasable Programmable Read-Only Memory (EPROM or Flash Memory), Compact Disc Read-Only Memory (CD-ROM), Local Area Network (LAN), Wide Area Network (WAN), Personal Digital Assistant (PDA), User Equipment (UE), Uplink (UL), Evolved Node B (eNB), Next Generation Node B (gNB), Downlink (DL), Central Processing Unit (CPU), Graphics Processing Unit (GPU), Field Programmable Gate Array (FPGA), Dynamic RAM (DRAM), Synchronous Dynamic RAM (SDRAM), Static RAM (SRAM), Liquid Crystal Display (LCD), Light Emitting Diode (LED), Organic LED (OLED), Multiple-Input Multiple-Output (MIMO), Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), Physical Downlink Shared Channel (PDSCH), Time division multiplexing (TDM), Code division multiplexing (CDM), Orthogonal Cover Code (OCC), Narrow Band Internet of Things (NB-IoT), wake up signal (WUS), paging occasion (PO), Identity (ID), Mobile Originating (MO), Mobile Terminated (MT), Circuit Switch (CS), Packet Switch (PS), Discontinuous Reception (DRX), Extended Discontinuous Reception (eDXR), Mobility Management Entity (MME), enhanced machine type of communication (eMTC), System Information Block (SIB), Radio Resource Control (RRC), Core Network (CN).

In NB-IoT technology, a wake up signal (WUS) mechanism is introduced for power saving, wherein the WUS indicates whether there is a paging process in a pre-defined paging occasion (PO).

Specifically, when the WSU mechanism is disabled, a UE always monitors paging messages on POs. When the WUS mechanism is enabled, the UE only monitors the following possible paging messages in POs in response to the UE receiving a WUS. PDCCH blind detection is used for monitoring the PO. On the other hand, when the WUS mechanism is enabled, the UE will stop monitoring the following paging messages in POs in response to the UE not receiving its WUS.

In R15, multiple UEs paged in the same PO may be associated to a same WUS. For example, ten (<NUM>) UEs monitor the same WUS. In this condition, if any one of the ten UEs is paged, the WUS will be sent. All of the ten UEs will receive the WUS. Therefore, all of the ten UEs including the paged UE and the other nine UEs that are not paged have to monitor the paging since the WUS is received. Since no actual paging information for the other nine UEs will be received, it is power wasting for these nine UEs to perform the PDCCH blind detection for paging.

To reduce this false alarm probability, in NB-IOT/eMTC R16 WI (Work Item), UE-group wake-up signal (WUS) is supported. So far, only UE_ID based grouping is agreed. For example, if the number of groups (N) is <NUM>, ten UEs could be grouped into <NUM> groups by UE_IDs mod N. That is, UEs with IDs <NUM>, <NUM> and <NUM> are in group1, UEs with IDs <NUM>, <NUM> and <NUM> are in group2, UEs with IDs <NUM> and <NUM> are in group3, and UEs with IDs <NUM> and <NUM> are in group4. The group4 may be named as group0.

Accordingly, if UE1, UE5 and UE9 are in the same group, the paging to UE1 will only trigger UE5 and UE9 to monitor the following paging, the other UEs that are not in the same group (for example, UEs <NUM>-<NUM>, <NUM>-<NUM> and <NUM>) do not need to monitor the paging. Therefore, only the UEs in the same group will monitor the same WUS and trigger the paging monitoring by this common WUS.

The UE_ID based grouping does not consider the services performed by the UEs. For example, some UEs are busy at night, some UE are busy in the morning. In other words, a service may be time-specific. It is obvious that if the UEs that are necessary to be paged at the same time are grouped together, then paging alarm probability can be reduced and the power saving can be achieved.

Although the above-described service-based grouping seems beneficial, it is not easy to describe the service-based grouping.

In this disclosure, we propose new parameters and methods to implement the UE grouping. <NPL> forms part of the related prior art.

Understanding that these drawings depict only some embodiments, and are not therefore to be considered as limiting of scope, the embodiments will be described and explained with additional specificity and detail using accompanying drawings, in which:.

Accordingly, embodiments may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may generally all be referred to herein as a "circuit", "module" or "system". Furthermore, embodiments may take the form of a program product embodied in one or more computer readable storage devices storing machine-readable code, computer readable code, and/or program code, referred to hereafter as "code".

Certain functional units described in this specification may be labeled as "modules", in order to more particularly emphasize their independent implementation. For example, a module may be implemented as a hardware circuit comprising custom very-large-scale integration (VLSI) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components.

Nevertheless, the executables of an identified module need not be physically located together, but, may include disparate instructions stored in different locations which, when joined logically together, include the module and achieve the stated purpose for the module.

Similarly, operational data may be identified and illustrated herein within modules and may be embodied in any suitable form and organized within any suitable type of data structure. This operational data may be collected as a single data set, or may be distributed over different locations including over different computer readable storage devices.

The computer readable storage medium may be a storage device storing code. The storage device may be, for example, but need not necessarily be, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

A non-exhaustive list of more specific examples of the storage device would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or Flash Memory), portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Code for carrying out operations for embodiments may be any number of lines and may be written in any combination of one or more programming languages including an object-oriented programming language such as Python, Ruby, Java, Smalltalk, C++, or the like, and conventional procedural programming languages, such as the "C" programming language, or the like, and/or machine languages such as assembly languages. The code may be executed entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the very last scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid any obscuring of aspects of an embodiment.

This code may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which are executed via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the schematic flowchart diagrams and/or schematic block diagrams for the block or blocks.

The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices, to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function specified in the schematic flowchart diagrams and/or schematic block diagrams block or blocks.

The code may also be loaded onto a computer, other programmable data processing apparatus, or other devices, to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the code executed on the computer or other programmable apparatus provides processes for implementing the functions specified in the flowchart and/or block diagram block or blocks.

<FIG> depicts an embodiment of a wireless communication system <NUM> for UE grouping. In one embodiment, the wireless communication system <NUM> includes remote units <NUM>, base units <NUM> and a control node <NUM>. Even though a specific number of remote units <NUM> and base units <NUM> are depicted in <FIG>, one skilled in the art will recognize that any number of remote units <NUM> and base units <NUM> may be included in the wireless communication system <NUM>.

In one embodiment, the remote units <NUM> may include computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs), tablet computers, smart phones, smart televisions (e.g., televisions connected to the Internet), set-top boxes, game consoles, security systems (including security cameras), vehicle on-board computers, network devices (e.g., routers, switches, modems), or the like. The remote units <NUM> may be referred to as subscriber units, mobiles, mobile stations, users, terminals, mobile terminals, fixed terminals, subscriber stations, user equipment (UE), user terminals, a device, or by other terminology used in the art. The remote units <NUM> may be Narrow Band Internet of Things (NB-IoT) terminals.

The base units <NUM> may be distributed over a geographic region. In certain embodiments, a base unit <NUM> may also be referred to as an access point, an access terminal, a base, a base station, a Node-B, an eNB, a gNB, a Home Node-B, a relay node, a device, or by any other terminology used in the art. The base units <NUM> are generally part of a radio access network that includes one or more controllers communicably coupled to one or more corresponding base units <NUM>. These and other elements of radio access and core networks are not illustrated, but are well known generally by those having ordinary skill in the art.

In one implementation, the wireless communication system <NUM> is compliant with 3GPP <NUM> new radio (NR). More generally, however, the wireless communication system <NUM> may implement some other open or pro prietary communication protocol.

The base units <NUM> may serve a number of remote units <NUM> within a serving area, for example, a cell (or a cell sector) or more cells via a wireless communication link.

The control node <NUM> is a control plane network element that handles signaling related to mobility and security for the remote units <NUM>. For example, the control node <NUM> may be a Mobility Management Entity (MME).

<FIG> depicts one embodiment of an apparatus <NUM> that may be used for UE grouping. The apparatus <NUM> includes one embodiment of the remote unit <NUM>. Furthermore, the remote unit <NUM> may include a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM>, and a receiver <NUM>. In some embodiments, the input device <NUM> and the display <NUM> are combined into a single device, such as a touch screen. In certain embodiments, the remote unit <NUM> may not include any input device <NUM> and/or display <NUM>. In various embodiments, the remote unit <NUM> may include at least one of the processor <NUM>, the memory <NUM>, the transmitter <NUM> and the receiver <NUM>, and may not include the input device <NUM> and/or the display <NUM>.

For example, the processor <NUM> may be a microcontroller, a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processing unit, a field programmable gate array (FPGA), or similar programmable controller.

For example, the memory <NUM> may include a RAM, including dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), and/or static RAM (SRAM). In some embodiments, the memory <NUM> stores data relating to system parameters.

In some embodiments, the input device <NUM> may be integrated with the display <NUM>, for example, as a touch screen or similar touch-sensitive display. In some embodiments, the input device <NUM> includes a touch screen such that text may be input using a virtual keyboard displayed on the touch screen and/or by handwriting on the touch screen.

As another, non-limiting example, the display <NUM> may include a wearable display such as a smart watch, smart glasses, a heads-up display, or the like.

For example, the input device <NUM> and display <NUM> may form a touch screen or similar touch-sensitive display.

The transmitter <NUM> is used to provide UL communication signals to the base unit <NUM> and the receiver <NUM> is used to receive DL communication signals from the base unit <NUM>. In various embodiments, the transmitter <NUM> and the receiver <NUM> may transmit and receive resources via different cells.

<FIG> depicts one embodiment of another apparatus <NUM> that may be used for UE grouping. The apparatus <NUM> includes one embodiment of the base unit <NUM>. Furthermore, the base unit <NUM> may include at least one of a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM> and a receiver <NUM>. As may be appreciated, the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> may be substantially similar to the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> of the remote unit <NUM>, respectively.

Although only one transmitter <NUM> and one receiver <NUM> are illustrated, the base unit <NUM> may have any suitable number of transmitters <NUM> and receivers <NUM>.

<FIG> depicts one embodiment of another apparatus <NUM> that may be used for UE grouping. The apparatus <NUM> includes one embodiment of the control node <NUM>. Furthermore, the control node <NUM> may include at least one of a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM> and a receiver <NUM>. As may be appreciated, the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM> and the receiver <NUM> may be substantially similar to the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> of the remote unit <NUM>, respectively.

<FIG> shows a method for UE grouping according to an embodiment.

In step <NUM>, the MME sends MME configuration to UE through eNB. The MME configuration could include information on whether or not the MME supports UE WUS grouping. In the condition that the MME supports UE WUS grouping, the MME configuration includes in the claimed invention whether the MME supports service-based grouping, or two-level grouping. The MME configuration could include UE parameter information used for service-base grouping. This configuration could support UE service-based grouping implicitly. This MME configuration could be sent in TAU procedure or in Attach procedure. Alternatively, this MME configuration could be sent in paging or SIB information through eNB.

The two-level grouping means that the UEs is grouped in two steps (two levels). The two-level grouping could be service-based and service-based grouping, or service-based and UE_ID-based grouping, or UE_ID-based and service-based grouping. The service-based and service-based grouping may mean that UEs will be grouped firstly by a first level service-based grouping, then one group set of UEs that is grouped by the first level service-based grouping will be further grouped by a second level service-based grouping. The second level service-based grouping may make more groups for the group set of UEs that is grouped by the first level service-based grouping. The service-based and UE_ID-based grouping may mean UEs will be grouped firstly by service-based grouping, then one group set of UEs that is grouped by the service-based grouping will be further grouped by UE_ID-based grouping. The UE_ID-based and service-based grouping may mean UEs will be grouped firstly by UE_ID-based grouping, then one group set of UEs that is grouped by the UE_ID-based grouping will be further grouped by service-based grouping.

In step <NUM>, the eNB sends eNB function information to the UE. The eNB function information may be sent by Radio Resource Control (RRC) signaling, by System Information Block (SIB) information, or by paging. The eNB function information may include information on whether or not the eNB supports WUS grouping. In the condition that the eNB supports WUS grouping, the eNB function information may include information on whether the eNB supports at least one of UE_ID-based grouping, service-based grouping, and/or two-level grouping. The eNB function information could include UE parameter information used for service-base grouping. This eNB function information could support UE service-based grouping implicitly. Alternatively, the eNB function information could include UE grouping parameter information used for service-base grouping. This eNB function information could support UE service-based grouping implicitly. The eNB function information could be sent in paging or SIB information by eNB.

In step <NUM>, the UE reports its function (UE function) to the eNB. The UE function may be determined based on its capability (UE capability), the MME configuration and the eNB function information. The UE function may indicate the following information: whether the UE supports WUS grouping; in the condition that the UE supports WUS grouping, whether the UE supports UE_ID-based grouping, service-based grouping, and/or two-level grouping; and in the condition of service-based grouping, what parameter is supported. The parameter for the service-based grouping will be discussed later. Incidentally, the UE function may be determined by the UE based on other factors. For example, even if the UE actually supports two-level grouping, the UE may report that it does not support the two-level grouping.

The steps <NUM>-<NUM> may not be necessary to be performed. The MME configuration, the eNB function information and the UE function may be predetermined. The UE function may also be known by the eNB or the MME.

In step <NUM>, the grouping rule information is generated. The grouping rule information indicates that at least one of UE_ID-based grouping, service-based grouping, and two-level grouping would be used to compute group_ID. The grouping rule information may be generated by the eNB or by the MME. The grouping rule information may be generated based on at least one of the UE function, the MME configuration and the eNB function information. The grouping rule information may inlcude at least one of the UE function, the MME configuration and the eNB function information. The eNB function information may include information on whether the eNB supports at least one of UE_ID-based grouping, service-based grouping, and/or two-level grouping. eNB supports at least one of UE_ID-based grouping, service-based grouping, and/or two-level grouping by explicit way or implicit way.

In step <NUM>, there are various ways to send the grouping rule information to the UE.

One possible way to send the grouping rule information to the UE is by using UE attach procedure or TAU (Tracking Area Update) procedure. The attach or TAU procedure is performed between the UE and MME through the eNB. Therefore, when the grouping rule information is determined by the MME, it is preferable to send the grouping rule information by UE attach or TAU procedure.

Another possible way to send the grouping rule information to the UE is by RRC signaling or SIB from eNB. When the grouping rule information is determined by the eNB, it is preferable to send the grouping rule information by RRC signaling or SIB from the eNB. Incidentally, when the grouping rule information is determined by the eNB, the eNB may notify the MME about the grouping rule information.

Yet another possible way to send the grouping rule information is by indicating in paging information. In the paging information, the service-based grouping could be enabled or disabled. When the service-based grouping is disabled, the UE_ID-based grouping will be used for the UE implicitly, so long as the UE function indicates that the UE supports the UE_ID-based grouping and eNB is able to configure the UE_ID-based grouping. When the service-based grouping is enabled, the UE_ID-based grouping and service-based grouping will be used for the UE, or the service-based grouping and UE_ID-based grouping will be used for the UE.

In step <NUM>, the UE, upon receiving the grouping rule information, computes a group_ID based on at least the grouping rule information.

If the UE_ID-based grouping is indicated in the grouping rule information, the UE uses a MOD calculation to compute the group_ID. If the service-based grouping or two-level grouping is indicated in the grouping rule information, more information is necessary for the UE to compute the group_ID.

A timer or time information could be applied to service-based grouping or a first level or a second level of the two-level grouping being service-based grouping. When timer or time based on time information is expired, the service-based grouping or a first level or a second level of the two-level grouping being service-based grouping will be stopped. The UE receives this timer or time information from the MME or the eNB.

For the service-based grouping, how to group UE based on a specific parameter has been discussed.

Service-ID and traffic pattern had been proposed to be used for the service-based grouping. However, based on the review on specification TS23. <NUM> and TS45. <NUM>, service-ID and traffic pattern are not suitable to be used. Service-ID is just the service-type information like the MO (Mobile Originating) or MT (Mobile Terminated) service by CS (Circuit Switch) or PS (Packet Switch), which could be not be used for grouping. The traffic pattern including network command is the same to all the UEs, which could be not be used for grouping, either.

In this disclosure, we propose the following parameters for use in the service-based grouping: paging probability (as claimed), service period, rating or frequency of service, and rating or frequency of service in a fixed cycle.

The paging probability is related to the times of service generating (paging) in a first period T1 and the number of paging occasions in a second period T2. The second period T2 may be the same as the first period T1. In particular, the paging probability is proportional to the times of service generating (paging) and inversely proportional to the number of paging occasions. More specifically, the paging probability is the ratio of the times of service generating (paging) in a first period T1 to the number of paging occasions in the second period T2.

The service period means period of service (or paging) in UE or time gap of two continuous services (or pagings) in UE. For example, UE1 reports its data per day while UE2 reports its data per hour. Therefore, the service period of UE1 is one day, and the service period of UE2 is one hour.

The rating or frequency of service means the service generating times in a predetermined period T3.

The rating or frequency of service in a fixed cycle means means the times of service generating in a fixed cycle. For example, the service may be a DL (downlink) CN (Core Network) command.

In step <NUM>, the eNB or the MME sends the parameter configuration to the UE in a similar manner to the transmission of the grouping rule information
In step <NUM>, upon receiving the parameter configuration, i.e. which parameter is used for the service-based grouping, the UE determines a value of the parameter for the UE.

The value of the parameter may be computed at the UE. Alternatively, the value of the parameter may be computed at the eNB or the MME and transmitted to the UE in a similar manner to the transmission of the grouping rule information
The grouping parameters are determined at the eNB or the MME and transmitted to the UE in a similar manner to the transmission of the grouping rule information. The value of the parameter and the grouping parameters are used for the UE to compute its group_ID.

On the other hand, it is also possible that the eNB or the MME determines the group_ID by using the value of the parameter and the grouping parameters, and sends the determined group_ID to the UE.

Different methods may be used to compute the group_ID.

In a first method, the group_ID is computed by a threshold-based method as shown in <FIG>. As shown in <FIG>, when the value of the parameter is in a zone between W(n-<NUM>) and W(n), the group_ID is computed as n. In particular, W(<NUM>) - W(n) are pre-determined thresholds. All of the values of the parameter falling within the zone from W(<NUM>) - W(<NUM>) belong to the first group, i.e. the group_ID = <NUM>. Similarly, the groupID for all of the values of the parameter falling within the zone from W(n-<NUM>) - W(n) is n. Incidentally, if the value of the parameter equals to W(n), its group_ID is n, except that if the value of the parameter equals to W(<NUM>), its group_ID is <NUM>.

Needless to say, the number of thresholds could be equal to the number of the groups (N) plus <NUM>.

For example, suppose that the number of the groups is <NUM>, and W(<NUM>) = <NUM>, W(<NUM>) = <NUM>, W(<NUM>) = <NUM>, W(<NUM>) = <NUM>, zone1 is the zone from W(<NUM>) to W(<NUM>), zone2 is the zone from W(<NUM>) to W(<NUM>), zone3 is the zone from (W2) to W(<NUM>). If the value of the parameter (x) for a UE is equal to <NUM> then x falls within the zone2. Accordingly, the groupID for the UE is <NUM>.

For another example, if the parameter is associated to service period and suppose that the number of the groups is <NUM>, and W(<NUM>) = <NUM> hours, W(<NUM>) = <NUM> hours, W(<NUM>) = <NUM> hours, W(<NUM>) = + infinite hours, then zone1 is the zone from W(<NUM>) to W(<NUM>), zone2 is the zone from W(<NUM>) to W(<NUM>), zone3 is the zone from W(<NUM>) to W(<NUM>). If the value of the parameter (x) for a UE is equal to <NUM> hours then x falls within the zone1. Accordingly, the groupID for the UE is <NUM>.

Needless to say, the number of thresholds could be equal to the number of the groups (N) plus <NUM>, or groups(N)-<NUM>, where the W(<NUM>) and W(N) are stored by UE according to the specification.

For yet another example, if the parameter is frequency of service and suppose that the number of the groups is <NUM>, and W(<NUM>) = <NUM>, W(<NUM>) = <NUM>, W(<NUM>) = <NUM>, W(<NUM>) = + infinite hours, then zone1 is the zone from W(<NUM>) to W(<NUM>), zone2 is the zone from W(<NUM>) to W(<NUM>), zone3 is the zone from (W2) to W(<NUM>). If the value of the parameter (x) for a UE is equal to <NUM> then x falls within the zone3. Accordingly, the groupID for the UE is <NUM>.

Needless to say, the number of thresholds could be equal to the number of the groups (N) plus <NUM>, or groups(N)-<NUM>, where the W(<NUM>) and W(N) are stored by UE according to the specification. This above methods using thresholds could also be applied to other types of parameters. The parameters could be rating or frequency of service, rating or frequency of service in a fixed cycle, or paging frequency.

The thresholds W(<NUM>) - W(n), or W(<NUM>)-W(N-<NUM>) may be configured by the eNB or the MME and sent to the UE.

In a second method, the group_ID is computed by the following equation: group_ID = ceil ((parameter x - minimum value) / step size), wherein step size = (maximum value - minimum value) / the number of groups. The maximum value and the minimum value represent the upper limit and the lower limit of the thresholds, and are pre-determined. <FIG> shows the second method.

For example, suppose that the number of the groups is <NUM>, and the minimum value (i.e. the lower limit of the thresholds) is <NUM>, the maximum value (i.e. the upper limit of the thresholds) is <NUM>, then the step size = (<NUM> - <NUM>) / <NUM> = <NUM> (<NUM>/<NUM>). If UE parameter x = <NUM>, then the group_ID = ceil ((<NUM> - <NUM>) / <NUM>) = <NUM>. Accordingly, the groupID for the UE is <NUM>. In other words, thresholds <NUM>, <NUM> (<NUM>/<NUM>), <NUM> (<NUM>/<NUM>) and <NUM> are calculated so that the values of the parameter falling within <NUM> and <NUM> (<NUM>/<NUM>) belong to group1, falling within <NUM> (<NUM>/<NUM>) and <NUM> (<NUM>/<NUM>) belong to group2, and falling within <NUM> (<NUM>/<NUM>) and <NUM> belong to group3.

Incidentally, given a specific number of the groups, since the step size can be calculated from the maximum value and the minimum value, it is also possible that the maximum value and the step size are predetermined (because the minimum value can be calculated from the maximum value and the step size) or the minimum value and the step size are predetermined (because the maximum value can be calculated from the minimum value and the step size). The step size could also be configured to UE by MME or eNB. The UE could receive the step size from MME or eNB, and computer its groupID based on this step size.

The above method using thresholds could also be applied to grouping with other types of parameters. The parameters could be rating or frequency of service, rating or frequency of service in a fixed cycle, or paging frequency.

In view of the above, the thresholds are calculated from the paging parameter (i.e. any two of the maximum value, the minimum value and the step size) and the number of groups. There are various ways to determine the paging parameter and the number of groups by MME and/or eNB.

For example, the paging parameter is configured by the MME and sent to the eNB. The eNB may determine the number of groups and receive the paging parameter from the MME, and use them to calculate the thresholds. In a second alternative, the paging parameter is configured by the MME, and the number of groups is determined by the eNB and sent to the MME. The MME uses the paging parameter received from the eNB and the paging parameter to calculate the thresholds. In a third alternative, both the paging parameter and the number of groups are configured by the MME. The MME uses them to calculate the thresholds. In a fourth alternative, both the paging parameter and the number of groups are determined by the eNB. The eNB uses them to calculate the thresholds. After the thresholds are calculated, they are transmitted to the UE from the eNB or the MME.

A third method applies to a second level grouping in the two-level grouping being service-based grouping. The first method or the second method may be used in a first level grouping being service-based grouping. After the first level grouping, there might be a situation in which a particular zone has a large number of UEs. For example, there are <NUM> UEs with parameters between <NUM>-<NUM>. These UEs could be further grouped into two sub-groups with a new threshold = sum of (UEs' values of the parameter) / the number of UEs. If there are more (more than two) sub-groups configured for the second level grouping, the thresholds for the sub-groups could be computed as follows:.

The number of UEs in a first level group is M. UE is reordered based on ascending parameters in the first level of the two-level grouping. The reordered UE could be noted as UE1 to UE M. The threshold parameters for a second level of the two-level grouping N' could be parameter of UE_m, where m = k * floor (M / N'), k=<NUM>,. , N'-<NUM>, or m = k * ceil (M / N'), k=<NUM>,. , N'-<NUM>, where N' is the number of second level groups for the UE in first level group.

For example, there are <NUM> UEs (i.e. M=<NUM>) with the values of the parameter from <NUM> to <NUM>, the <NUM> UEs' values could be <NUM> for <NUM> UEs (UE1 to UE3), <NUM> for <NUM> UEs (UE4 to UE5), <NUM> for 3UEs (UE6 to UE8) and <NUM> for <NUM> UEs (UE9 to UE10), and the number of sub-groups for the second level grouping is <NUM>.

The thresholds could be determined as threshold1 = <NUM> (the value of the parameter of UE3), threshold <NUM> = <NUM> (the value of the parameter of UE6). Thus the UE1, UE2, UE3 will be in a group1, UE4 to UE8 will be in a group2, UE9 and UE10 will in a group3. Incidentally, since UE7 and UE8 have the same value <NUM> as UE6, they (UE7 and UE8) are also in the group2. This grouping result supports a principle that similar parameters will be in the same group, and the number of UEs in each group is similar to each other, which could avoid the defect that too many UEs are in the same group to reduce the efficiency of grouping.

The thresholds used for the sub-groups may be referred to as sub-thresholds. The sub-thresholds may be configured in a similar manner to the first method, i.e. configured by the eNB or the MME and sent to the UE. Alternatively, the sub-thresholds may be calculated in a similar manner to the second method, i.e. calculated by the eNB or the MME and sent to the UE.

The above method using thresholds could also be applied to grouping with other types of parameters. The parameters could be service period, rating or frequency of service, rating or frequency of service in a fixed cycle, or paging frequency.

In all of the above-described methods <NUM>-<NUM>, the parameter could be any one of paging probability, service period, rating or frequency of service, and rating or frequency of service in a fixed cycle. The parameter could be also be paging frequency, or paging cycle. Service period could be named as paging period. Rating or frequency of service could be named as rating or frequency of paging.

The preferable parameter is the paging probability or the service period.

In the service-based and service-based grouping, the same parameter or different parameters may be used in a first level service-based grouping and a second level service-based grouping.

Considering that the service may be time-specific. For example, suppose that the UE is a street light that may be turned ON or OFF at night or in the morning, the parameters (for example the paging probabilities) are different in different time periods. Therefore, the grouping parameters may be different in different time periods.

Therefore, the grouping parameters may be TA (Tracking Area)-specific, or eNB-specific, or UE-specific, or PO (paging occasion)-specific, or eNB-specific and time-specific. For TA (Tracking Area)-specific grouping paramters, the grouping parameters may be the same for UEs in a Tracking area. The grouping parameters could be sent to the UE by the MME in TAU or attach procedure, or by the MME or the eNB by paging information or System information. For eNB-specific grouping parameters, the grouping parameters may be the same for UEs in a eNB area. For UE-specific grouping parameters, the grouping parameters may be configured to an individual UE. For PO (paging occasion)-specific, the grouping paramters may be configured based on a specific paging occasion position. For eNB-specific and time-specific grouping parameters, the grouping parameters may be the same for UEs in a eNB, and could be associated to the time information. The grouping parameters here are the parameters used to grouping. For example, grouping parameters could be the thresholds to group the UE based on UE's parameter value. The grouping parameters could be sent to the UE by the MME in TAU or attach procedure, or by MME or eNB by paging information or System information.

In step <NUM>, the UE monitors WUS related to the group_ID. Here, the WUS with single sequence CDM could be multiplexed by UEs based on different group rules. A WUS with single sequence CDM means that one type of group set is associated to a WUS. Accordingly, only one WUS needs to be transmitted no matter what kind of group set is shown. The WUS with single sequence CDM is designed based on Code information. The Code information could be designed by at least one of frequency domain orthogonal cover codes, scrambling initialization, phase shifted scrambling codes, and Zadoff-Chu phase shift. For example, the WUS with single sequence CDM for service-based grouping could be TDM (Time-Division Multiplexing) with the WSU with single sequence CDM for UE-ID based grouping. The WUS with single sequence CDM for service-based grouping could be FDM (Frequency-Division Multiplexing) with the WSU with single sequence CDM for UE-ID based grouping. Thus, the WUS with single sequence CDM could be multiplexed by UEs based on different group rules The multiplexing method could be one of TDM, FDM or CDM, or the combination of TDM, FDM and CDM. The WUS with single sequence CDM could also be used for two-level grouping. Here, a group set, for example, means that UEs in group_n within the group set is paged or not, where n could be from <NUM> to N-<NUM>, N is the number of groups. The group set, for example, could be a set consisted by group1, group2, group5, this means at least one of UEs in group1, at least one of UEs in group2, and at least one of UEs in group5 are paged. The offset in time domain between a WUS with single sequence CDM for one UE grouping rule and a WUS with single sequence CDM for another UE grouping rule will be transmitted to UE. UE will receive the offset in time domain between a WUS with single sequence CDM for one UE grouping rule and a WUS with single sequence CDM for another UE grouping rule from eNB or MME. Based on this offset, UE will monitor the WUS associated to its grouping rule.

In step <NUM>, once the WUS is received, the UE receives paging in a paging occasion. As described above, the paging information may also include an indication that the service-based grouping is enabled or disabled for the next WUS.

In this document, the paging times could be the paging times caused by service, or the paging times caused by service and paging by System information updating. The paging could be the paging caused by service, or the paging caused by service and caused by System information updating.

Claim 1:
A method at a remote unit (<NUM>), comprising:
receiving grouping rule information; and
computing a group_ID based on at least the grouping rule information, wherein the grouping rule information indicates that the groupID is computed based on service-based grouping or two-level grouping, wherein a first level or a second level of the two-level grouping is service-based grouping;
receiving a value of a parameter, the parameter being a paging probability; and
receiving a plurality of thresholds, wherein the groupID is calculated based on the value of the parameter and the plurality of thresholds.