Patent Description:
Certain abbreviations that may be found in the description and/or in the figures are herewith defined as follows:.

Mobile communication will be a key enabler in achieving objectives of the fourth industrial revolution (Industrial <NUM>). It goes along with a need for coherent integration and migration strategies to transform existing industrial production, which is mostly based on fixedline networks, toward the next level of industrial production, which will make use of ubiquitous, highly reliable and ultra-low-latency wireless communication networks. One critical enabler for Industry <NUM> is scalable and pervasive connectivity between machines, people and objects which is called as the Industrial Internet of Things (IIoT), for which wireless connectivity will play a pivotal role. Mobile and wireless communication systems also offer benefits in removing cables from stationary, rotating or other devices with limited mobility. Ubiquitous connectivity is a key characteristic of mobile communication systems, which enables flexible manufacturing setups and reconfiguration not constrained by available cabling. It means that the devices in the factory which were linked with cables before will link via a wireless communication system and follow the wireless system protocols.

<CIT> discloses a paging method and device. The paging method comprises the steps that network equipment receives a random access preamble from terminal equipment; wherein the random access preamble is used for requesting a paging message; and the network equipment acquires a paging identifier associated with the random access preamble, and the network equipment sends a paging message to the terminal equipment according to the paging identifier.

The present invention is as set out in the independent claims.

Some example embodiments will now be described, by way of non-limiting examples, with reference to the accompanying drawings.

Throughout the drawings, same or similar reference numbers indicate same or similar elements. A repetitive description on the same elements would be omitted.

Herein below, some example embodiments are described in detail with reference to the accompanying drawings. The following description includes specific details for the purpose of providing a thorough understanding of various concepts. In some instances, well known circuits, techniques and components are shown in block diagram form to avoid obscuring the described concepts and features.

In <NUM>/<NUM> and earlier generations of mobile communication systems, when the network wants to connect with a UE, the network will send a paging message to the UE. After receiving the paging message, the UE will perform a random access procedure for the initial access to the network.

<FIG> illustrates a four-steps random access procedure. As is shown in <FIG>, in Step <NUM>, a UE <NUM> transmits to a BS <NUM> Msg <NUM> including a preamble on PRACH. In Step <NUM> the BS <NUM> transmits to the UE <NUM> an RAR as Msg <NUM> including a time-alignment command for adjusting the uplink transmission timing of the UE <NUM> based on the timing of the received preamble, and an UL Grant. Following Steps <NUM> and <NUM> are to resolve contention due to simultaneous transmissions of the same preamble from multiple UEs <NUM> within a cell. In Step <NUM>, the UE <NUM> transmits to the BS <NUM> an RRC connection request as Msg <NUM> using the UL Grant allocated in Msg <NUM>. In Step <NUM>, the BS <NUM> transmits an Msg <NUM> including C-RNTI or identity of a successful connected UE <NUM> for contention resolution. And there may be an additional Step <NUM> for transmitting Msg <NUM> of RRC response from the successful connected UE <NUM> to the BS <NUM>. In this procedure a collision occurs when a plurality of UEs <NUM> use the same preamble and begin the random access procedure at the same time due to the limited preamble number (<NUM> or less) and PRACH frequency and timing domain resource. Only one UE <NUM> among those having collision with each other can connect with the BS <NUM> while others need to do the random access procedure again.

To shorten time for random access, a two-steps random access procedure has been proposed for NR, which is shown in <FIG>. Referring to <FIG>, the UE <NUM> transmits to the BS <NUM> an Msg A combining the Msg <NUM> and Msg <NUM> in Step A and the BS <NUM> transmits to the UE <NUM> an Msg B combining the Msg <NUM> and Msg <NUM> in Step B. Compared with the four-steps procedure shown in <FIG>, the two-steps procedure can reduce the time length of the whole random access procedure, but the collision possibility increases because the Step A needs both PUSCH resource and RACH resource.

<FIG> illustrates a scenario of example factory <NUM> where a large number of IIoT devices <NUM> including for example UEs <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM> connect wirelessly to a BS <NUM>. In the factory <NUM>, the network (the control centre) will trigger the large number of devices <NUM> to start up and begin or get ready to work at substantially the same time everyday, which means that all the devices <NUM> commence a random access procedure with the BS <NUM> at substantially the same time. In a legacy system where the devices <NUM> are connected with cables, there is no problem for the devices <NUM> to connect to the network at the same time. But in a wireless system, many devices <NUM> may fail the contention-based random access procedure because of limited RACH and PUSCH resources, and they need to do the random access procedure again and again. A device which cannot connect to the network on time will also make other devices that depend on its operation cannot work and must wait. It will take a long time to make all the devices <NUM> connected and ready for work. This is a waste of time and money for the factory.

The IIoT devices <NUM> may be set in an idle or inactive state for saving power consumption. When a device <NUM> in the idle or inactive state has UL or DL data to transmit or receive, it needs to setup or resume an RRC connection with the network. The connection setup/resumption and subsequent release/suspension to the idle/inactive state happens for each data transmission, no matter how small and infrequent the data packets are. This results in unnecessary latency, power consumption and signaling overhead.

Embodiments of an enhanced paging procedure will be discussed below. The enhanced paging procedure may be used for, among others, a random access procedure or small data transmission, which can shorten time length and improve efficiency of the procedure, especially for IIoT devices.

<FIG> illustrates an interaction diagram of example operations between a network device such as the BS <NUM> and a terminal device such as the UE <NUM> in an enhanced paging procedure in accordance with some example embodiments. The enhanced paging procedure may be applied in a scenario for example a factory where the UE <NUM> does not move or only moves within a limited area when it is in an idle or inactive state. If the UE <NUM> keeps moving when it is in the idle or inactive state, a legacy paging procedure may be applied. The enhanced paging procedure may be triggered by an access and mobility management function (AMF) sending a legacy paging for the UE <NUM> to the BS <NUM>, or may be triggered by the BS <NUM> when the BS <NUM> has DL data for the UE <NUM> or needs UL data from the UE <NUM>.

As shown in <FIG>, in Operation <NUM>, the BS <NUM> may allocate an UL grant for the UE <NUM>. It is assumed that the UE <NUM> is in an RRC_IDLE or RRC_INACTIVE state, and the BS <NUM> is aware of that the UE <NUM> would not move or only move within a limited area when it is in the idle or inactive state by for example receiving a mode or capability indicator from the UE <NUM>. The allocated UL grant schedules PUSCH resources for the UE <NUM> to transmit UL signal to the BS <NUM>. In Operation <NUM>, the BS <NUM> may transmit an enhanced paging message to the UE <NUM>. Compared with a legacy paging message that includes only an identity of the UE, the enhanced paging message transmitted in Operation <NUM> further includes the UL grant allocated to the UE <NUM>. Then in Operation <NUM> the UE <NUM> may transmit a signal to the BS <NUM> using the UL grant.

The signal <NUM> may comprise any control signaling or data that the UE <NUM> needs to transmit to the BS <NUM>. In some embodiments, the signal <NUM> may comprise small and infrequent data for the BS <NUM>. Thus, UL small data transmission is accomplished while the UE <NUM> does not need to enter into the RRC_CONNECTED state. It improves the communication efficiency and saves power consumption and signaling overhead incurred by the random access procedure.

In some embodiments, before transmitting the signal <NUM>, the UE <NUM> adjusts in Operation <NUM> its uplink transmission timing based on Timing Advance (TA) to compensate for the propagation delay as the signal travels between the UE <NUM> and the BS <NUM>. The TA may be stored at the BS <NUM> and/or at the UE <NUM> when the UE <NUM> enters into the RRC_IDLE or RRC_INACTIVE state and it has a value that depends on a transmission delay between the UE <NUM> and the BS <NUM>. As the UE <NUM> does not move or only moves within a limited area when it is in the idle or inactive state, the TA stored when the UE <NUM> entered into the idle or inactive state is still applicable throughout the time period that the UE <NUM> is in the idle or inactive state, and a Random Access (RA) procedure is not needed. And also, the network knows which cell the UE <NUM> camped recently. In some embodiments, when the UE <NUM> enters into the idle or inactive state, the cell on which the UE <NUM> camped will store the UE's ID and TA, and the UE's ID and TA would be included in the paging message <NUM> together with the UL grant for the UE <NUM>. In some embodiments, the UE <NUM> may also store its TA when it enters into the idle or inactive state and thus the paging message <NUM> does not need to include the TA for the UE <NUM>.

<FIG> illustrates another embodiment of the enhanced paging procedure. The operations in <FIG> the same as or similar to those in <FIG> are denoted with the same or similar numerals and a repetitive description will be omitted. Hereinafter only difference between the procedures of <FIG> will be detailed.

Referring to <FIG>, the enhanced paging message <NUM>' transmitted from the BS <NUM> to the UE <NUM> further includes DL data, RRC signaling or NAS signaling for the UE <NUM>, in addition to the UE's ID and UL grant. The DL data may be any data for the UE <NUM> and it may originate from the BS <NUM>, the core network or other network or terminal devices. The signal <NUM>' transmitted from the UE <NUM> to the BS <NUM> using the UL grant may comprise a response to acknowledge receipt of the paging message <NUM>', UL data, RRC message or NAS signaling. Thus, DL small data transmission is accomplished while the UE <NUM> does not need to enter into the RRC_CONNECTED state. It improves the communication efficiency and saves power consumption and signaling overhead incurred by the random access procedure.

The enhanced paging procedure may also be used for random access in a scenario for example the factory <NUM> where a large number of IIoT devices such as the UEs <NUM> need to connect to the BS <NUM> at the same time. <FIG> illustrates an interaction diagram of example operations for a random access procedure taking advantage of the enhanced paging in accordance with some example embodiments.

Referring to <FIG>, when the UE <NUM> connects to the network of the factory <NUM> at the very first time, the network does not have any context of the UE <NUM>, and a legacy initial random access procedure may be performed at Operation <NUM> for the UE <NUM> to access the network at the BS <NUM>. The legacy initial random access procedure may be a four-steps procedure shown in <FIG> or a two-steps procedure shown in <FIG>.

Then, the UE <NUM> may transmit a mode indicator or a capability indicator to the BS <NUM> in Operation <NUM>. The mode/capability indicator indicates that the UE <NUM> is in a factory working mode and it supports a tailored random access procedure based on the enhanced paging message comprising an UL grant and possibly a TA value. For example, the UE <NUM> may set an information element (IE), e.g. factoryWorkingMode, to ON and send it as the mode/capability indicator to the BS <NUM>. The UE <NUM> may send the mode/capability indicator to the BS <NUM> at any time before it goes into an idle or inactive state. For example, the mode/capability indicator may be included in an RRC setup complete message (Msg5) sent to the BS <NUM>, or it may be sent to the BS <NUM> when the UE <NUM> reports its capabilities to the BS <NUM>. The BS <NUM> stores the mode/capability indicator in Operation <NUM> when it receives the mode/capability indicator from the UE <NUM>.

It is assumed that the UE <NUM> goes into an idle or inactive state by releasing or suspending the RRC connection in Operation <NUM>. In Operation <NUM>, the BS <NUM> may store the UE's <NUM> ID and TA when the UE <NUM> goes into the idle or inactive state.

In Operation <NUM>, the BS <NUM> may receive a legacy paging for the UE <NUM> from an AMF (not shown). For example, the AMF pages all the UEs <NUM> of the factory <NUM> to trigger a random access procedure and makes the UEs <NUM> get ready for working. When receiving a paging message for the UE <NUM>, the BS <NUM> checks in Operation <NUM> the mode/capability indicator of the UE <NUM> to determine if the UE <NUM> supports an enhanced paging message. If so, the BS <NUM> will initiate the enhanced paging for a tailored random access as discussed below. Otherwise, the BS <NUM> will initiate a legacy paging to trigger a legacy two-step or four-step random access.

It is further assumed that the mode/capability indicator (e.g. factoryWorkingMode) is ON. In Operation <NUM>, the BS <NUM> may allocate UL grant and RRC resources for the UE <NUM>. If the UE <NUM> is in the idle state, the BS <NUM> may also assign a cell specific radio network temporary identifier (C-RNTI) for the UE <NUM>. If the UE <NUM> is in the inactive state, it still maintains its C-RNTI for the cell it camped and the maintained C-RNTI can be used. In some embodiments, the BS <NUM> also retrieves TA for the UE <NUM> if the TA is stored at the BS <NUM> when the UE <NUM> goes into the idle or inactive state in Operation <NUM>. The UL grant, the TA and the C-RNTI for the UE <NUM> may be packaged in Random Access Response (RAR). The allocated RRC resources may be packaged in an RRC setup message if the UE <NUM> is in the idle state or in an RRC resume message if the UE <NUM> is in the inactive state. In Operation <NUM>, the BS <NUM> may transmit an enhanced paging message including the RAR payload (including UL grant and optionally TA and C-RNTI) and the RRC setup or resume message to the UE <NUM>. As such, the enhanced paging message transmitted in Operation <NUM> combines Msg2 and Msg4 of the legacy random access procedure, and a PRACH preamble is not needed.

In Operation <NUM>, the UE <NUM> may adjust its transmission timing based on the TA received in the paging message from the BS <NUM> or stored at the UE <NUM>. In the scenario factory <NUM>, the IIoT UEs do not move or may be moved only within a very limited area when the UEs stop working and stay in the idle or inactive state, so the TA stored when the UE <NUM> goes in the idle or inactive state can still be used in Operation <NUM>. Then, the UE <NUM> may transmit an RRC response to the BS <NUM> using the UL grant in Operation <NUM> and enter into the RRC_CONNECTED state in Operation <NUM>. The RRC response may include for example an RRC setup or resume complete message.

Compared with the legacy four-steps or two-steps random access procedure, the tailored random access procedure based on the enhanced paging message discussed above includes only one step of transmitting the enhanced paging message. It greatly shortens the time length of the random access procedure. The tailored random access based on the enhanced paging procedure also avoids contention between a number of UEs because the PRACH preamble is not used. Thus, a large number of UEs can connect to the network at the same time. It is especially beneficial for a scenario such as the factory <NUM> where a large number of IIoT devices need to connect to the network at the same time.

<FIG> illustrates a flow chart of an example method <NUM> for the enhanced paging procedure in accordance with some example embodiments. For a better understanding, the below description of method <NUM> may be read also with reference to <FIG>. The method <NUM> may be performed for example at an IIoT UE such as the UE <NUM>.

As shown in <FIG>, the example method <NUM> may include a step <NUM> of receiving a paging message from a network device, and a step <NUM> of transmitting a signal to the network device. The paging message may comprise an identity of the UE and an UL grant allocated for the UE, and the signal may be transmitted using the UL grant. The network device may be for example a BS such as the BS <NUM>, and the signal may comprise any control signaling or uplink data for the BS <NUM>.

In some embodiments, the paging message may further comprise downlink data for the UE. The signal transmitted in the step <NUM> may comprise a response to acknowledge receipt of the downlink data at the UE.

The paging message further comprises an RRC setup or resume message. The example method <NUM> may further include a step <NUM> of entering into a connected state from an idle or inactive state in response to the RRC setup or resume message. In such a case, the signal transmitted to the network device using the UL grant comprises an RRC setup or resume complete message that is transmitted when the UE enters into the connected state.

In some embodiments, the paging message may further comprise a C-RNTI for the UE. For example, if the UE <NUM> is in the idle state and is to enter into a connected or inactive state, the C-RNTI for the UE <NUM> may be included in the paging message.

In some embodiments, the example method <NUM> may further include a step <NUM> of adjusting transmission timing based on a TA for the UE, before transmitting the signal <NUM>. The TA may be stored at the network device when the UE goes into an idle or inactive state and received in the paging message from the network device, or stored at the UE when the UE goes into the idle or inactive state.

In some embodiments, the example method <NUM> may further include a step <NUM> of transmitting a mode indicator to the network device. The mode indicator may indicate whether the UE is in a mode that supports the paging message comprising an UL grant. When the network device checks the mode/capability indicator and determines that the UE supports the paging message comprising the UL grant, the network device will transmit the paging message in Operation <NUM>.

<FIG> illustrates a block diagram of an example apparatus <NUM> in accordance with some example embodiments. The apparatus <NUM> may be implemented in for example the UE <NUM> to perform the method <NUM> shown in <FIG>. Referring to <FIG>, the apparatus <NUM> may include a first means (or module) <NUM> for performing the step <NUM>, and a second means <NUM> for performing the step <NUM>. The apparatus <NUM> may further include a third means <NUM> for performing the step <NUM>, a fourth means <NUM> for performing the step <NUM>, and a fifth means <NUM> for performing the step <NUM>.

<FIG> illustrates a flow chart of an example method <NUM> for the enhanced paging procedure in accordance with some example embodiments. For a better understanding, the below description of method <NUM> may be read also with reference to <FIG>. The method <NUM> may be performed for example at a network device such as the BS <NUM>.

As shown in <FIG>, the example method <NUM> may include a step <NUM> of allocating an UL grant for a UE, a step <NUM> of transmitting a paging message to the UE, and a step <NUM> of receiving a signal transmitted from the UE using the UL grant. The paging message may comprise an identity of the UE and the UL grant.

In some embodiments, the BS <NUM> may allocate an UL grant for the UE <NUM> in response to a legacy paging message including the ID of the UE <NUM> from for example an AMF function in the core network.

In some embodiments, the example method <NUM> may further include a step <NUM> of storing the UE's identity and TA when the UE enters into an idle or inactive state. In such a case, the paging message transmitted in the step <NUM> may further comprise the TA for the UE. In some embodiments, the TA may be stored at the UE <NUM> and the paging message transmitted in the step <NUM> may not include the TA for the UE.

In some embodiments, the paging message may further comprise downlink data for the UE, and the signal received on the UL grant from the UE may comprise a response to acknowledge receipt of the downlink data. Therefore, downlink small data transmission is accomplished while the UE <NUM> does not need to translate from the idle or inactive state to the connected state.

In some embodiments, the signal received on the UL grant from the UE may comprise uplink data for the network device. Therefore, uplink small data transmission is accomplished while the UE <NUM> does not need to transition from the idle or inactive state to the connected state.

The paging message further comprises an RRC setup or resume message. The signal received on the UL grant from the UE comprises an RRC setup or resume complete message.

In some embodiments, the paging message may further comprise a C-RNTI for the UE.

In some embodiments, the example method <NUM> may further include a step <NUM> of checking a mode indicator stored at the network device to determine whether the UE is in a mode that supports the paging message comprising an UL grant. The paging message comprising the UL grant is transmitted in the step <NUM> when it is determined in the step <NUM> that the UE is in the mode that supports such a paging message.

The steps <NUM>-<NUM> of the method <NUM> are performed in cooperation with the steps <NUM>-<NUM> of method <NUM> to implement the enhanced paging procedure discussed above. Thus, various features and aspects described above with respect to the example method <NUM> are also applicable to or included in the example method <NUM>.

<FIG> illustrates a block diagram of an example apparatus <NUM> in accordance with some example embodiments. The apparatus <NUM> may be implemented in for example the BS <NUM> to perform the method <NUM> shown in <FIG>. Referring to <FIG>, the apparatus <NUM> may include a first means (or module) <NUM> for performing the step <NUM>, a second means <NUM> for performing the step <NUM>, and a third means <NUM> for performing the step <NUM>. Optionally, the apparatus <NUM> may further include a fourth means <NUM> for performing the step <NUM> and a fifth means <NUM> for performing the step <NUM>.

<FIG> illustrates a block diagram of an example communication system <NUM> in which embodiments of the present disclosure can be implemented. As shown in <FIG>, the communication system <NUM> may comprise user equipment (UE) <NUM> which may be implemented as the IIoT UE <NUM> discussed above, and a network device <NUM> which may be implemented as the BS <NUM> discussed above. Although <FIG> shows only one UE <NUM>, it would be appreciated that the communication system <NUM> may comprise a plurality of UEs <NUM> that wirelessly connect to the network device <NUM>.

Referring to <FIG>, the UE <NUM> may comprise one or more processors <NUM>, one or more memories <NUM> and one or more transceivers <NUM> interconnected through one or more buses <NUM>. The one or more buses <NUM> may be address, data, or control buses, and may include any interconnection mechanism such as series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. Each of the one or more transceivers <NUM> may comprise a receiver and a transmitter, which are connected to one or more antennas <NUM>. The UE <NUM> may wirelessly communicate with the network device <NUM> through the one or more antennas <NUM>. The one or more memories <NUM> may include computer program code <NUM>. The one or more memories <NUM> and the computer program code <NUM> may be configured to, when executed by the one or more processors <NUM>, cause the user equipment <NUM> to perform processes and steps relating to the UE <NUM> as described above.

The network device <NUM> may comprise one or more processors <NUM>, one or more memories <NUM>, one or more transceivers <NUM> and one or more network interfaces <NUM> interconnected through one or more buses <NUM>. The one or more buses <NUM> may be address, data, or control buses, and may include any interconnection mechanism such as a series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. Each of the one or more transceivers <NUM> may comprise a receiver and a transmitter, which are connected to one or more antennas <NUM>. The network device <NUM> may operate as a base station for the UE <NUM> and wirelessly communicate with the UE <NUM> through the one or more antennas <NUM>. The one or more network interfaces <NUM> may provide wired or wireless communication links through which the network device <NUM> may communicate with other network devices, entities or functions. The one or more memories <NUM> may include computer program code <NUM>. The one or more memories <NUM> and the computer program code <NUM> may be configured to, when executed by the one or more processors <NUM>, cause the network device <NUM> to perform processes and steps relating to the BS <NUM> as described above.

The one or more processors <NUM>, <NUM> discussed above may be of any appropriate type that is suitable for the local technical network, and may include one or more of general purpose processors, special purpose processor, microprocessors, a digital signal processor (DSP), one or more processors in a processor based multi-core processor architecture, as well as dedicated processors such as those developed based on Field Programmable Gate Array (FPGA) and Application Specific Integrated Circuit (ASIC). The one or more processors <NUM>, <NUM> may be configured to control other elements of the UE/network device and operate in cooperation with them to implement the procedures discussed above.

The one or more memories <NUM>, <NUM> may include at least one storage medium in various forms, such as a volatile memory and/or a non-volatile memory. The volatile memory may include but not limited to for example a random access memory (RAM) or a cache. The non-volatile memory may include but not limited to for example a read only memory (ROM), a hard disk, a flash memory, and the like. Further, the one or more memories <NUM>, <NUM> may include but not limited to an electric, a magnetic, an optical, an electromagnetic, an infrared, or a semiconductor system, apparatus, or device or any combination of the above.

The network device <NUM> can be implemented as a single network node, or disaggregated/distributed over two or more network nodes, such as a central unit (CU), a distributed unit (DU), a remote radio head-end (RRH), using different functional-split architectures and different interfaces.

It would be understood that blocks in the drawings may be implemented in various manners, including software, hardware, firmware, or any combination thereof. In some embodiments, one or more blocks may be implemented using software and/or firmware, for example, machine-executable instructions stored in the storage medium. In addition to or instead of machine-executable instructions, parts or all of the blocks in the drawings may be implemented, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-Programmable Gate Arrays (FPGAs), Application-Specific Integrated Circuits (ASICs), Application-Specific Standard Products (ASSPs), System-on-Chip systems (SOCs), Complex Programmable Logic Devices (CPLDs), etc..

Some exemplary embodiments further provide computer program code or instructions which, when executed by one or more processors, may cause a device or apparatus to perform the procedures described above. The computer program code for carrying out procedures of the exemplary embodiments may be written in any combination of one or more programming languages. The computer program code may be provided to one or more processors or controllers of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented.

Some exemplary embodiments further provide a computer program product or a computer readable medium having the computer program code or instructions stored therein. The computer readable medium may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but is not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Claim 1:
An apparatus (<NUM>), implemented at a user equipment, UE, (<NUM>), the apparatus (<NUM>) comprising:
means (<NUM>) for receiving a paging message from a network device (<NUM>), the paging message comprising an identity of the UE (<NUM>) and an UL grant;
means (<NUM>) for transmitting a signal to the network device (<NUM>) using the UL grant;
wherein the paging message further comprises a radio resource control, RRC, setup or resume message; and
wherein the signal, transmitted to the network device (<NUM>) using the UL grant, comprises an RRC setup or resume complete message.