INFORMATION CHANGE NOTIFICATIONS

TECHNICAL FIELD

Certain embodiments of the present disclosure relate, in general, to wireless communications and more particularly to fast load control through paging-based system information change notifications.

BACKGROUND

An important property of the coming 5G system (e.g. NR), which is relevant also in the context of the present disclosure, is the usage of high carrier frequencies, e.g. in the range 6-100 GHz. For such high frequency spectrum, the atmospheric, penetration and diffraction attenuation properties can be much worse than for lower frequency spectrum. In addition, the receiver antenna aperture, as a metric describing the effective receiver antenna area that collects the electromagnetic energy from an incoming electromagnetic wave, is inversely proportional to the frequency, i.e., the link budget would be worse for the same link distance even in a free space scenario, if omnidirectional receive and transmit antennas are used. This motivates the usage of beamforming to compensate for the loss of link budget in high frequency spectrum. This is particularly important when communicating with user equipments (UEs) with poor receivers, e.g. low cost/low complexity UEs. Other means for improving the link budget include repetition of the transmissions (e.g. to allow wide beam or omnidirectional transmission) or use of Single Frequency Network (SFN) transmission from multiple Transmission/Reception Points (TRPs) in the same or different cells.

For the 5G system currently being standardized by 3GPP (where the radio access network is referred to as New Radio (NR) and the core network is referred to as Next Generation Core (NGC)) 3GPP has agreed to partly change the principles for distribution of system information (SI) that are used in LTE.

For NR it has been decided to divide the SI into "minimum SI" and "other SI", where the minimum SI is the SI that is required to access the cell. The minimum SI is periodically broadcast in a cell, while the other SI may be either periodically broadcast or delivered on demand, e.g. triggered by a random access preamble (also referred to as Msgl) or a random access message 3 (also referred to as Msg3) from a UE in RRC IDLE or RRC INACTIVE state or requested via RRC signaling from a UE in RRC C ONNEC TED state. If random access preamble (Msgl) transmissions are used, there may be different preambles for requesting different parts (e.g. SIB(s) or groups of SIBs or SI message(s)) of the other SI. If random access message 3 (Msg3) transmissions are used, a UE may in such a message specify which parts (e.g. SIB(s) or groups of SIBs or SI message(s)) of the other SI the UE wants the network to broadcast/transmit.

With the Msgl solution, reception of one of the concerned dedicated preambles triggers the network to broadcast the requested SIB(s) in accordance with scheduling information in the minimum SI. The network, e.g., the g B, also transmits a Msg2 to the requesting UE, in response to the Msgl, confirming the successful reception of the Msgl and confirming that the requested SI will be broadcast. When a UE uses the Msgl method for request of on-demand SI, it selects the preamble associated with the desired on-demand SI (as specified in the minimum SI) and transmits this preamble to the network using PRACH resources. The UE then awaits the confirming Msg2 (during a Msg2 window) and after receiving the confirming Msg2 the UE monitors the downlink for the broadcast of the requested SI in accordance with the scheduling information for the requested SI, as indicated in the minimum SI. The procedure is illustrated in FIGURE 1 (the message sequence of the Msgl solution for requesting broadcast/transmission of other SI).

With the Msg3 solution, the request procedure begins like a regular random access procedure - i.e. the UE transmits one of the regular (non-dedicated) preambles in Msgl and receives a regular Msg2 in response, where the Msg2, as any regular Msg2, allocates uplink transmission resources for transmission of Msg3, as well as provides a timing advance indication to enable the UE to transmit Msg3 with correct timing. The SI request included in Msg3 triggers the network to broadcast/transmit the parts of the other SI that are specified in the Msg3 from the UE in accordance with scheduling information in the minimum SI. The network, e.g., the gNB, also transmits a Msg4 confirming the successful reception of the Msg3 and confirming that the requested SI will be broadcast. When a UE uses the Msg3 method for request of on-demand SI, it randomly selects one of the regular non-dedicated preambles (as specified in the minimum SI) and transmits this preamble to the network using PRACH resources. The UE then awaits Msg2 (during a Msg2 window) and after receiving the Msg2 the UE transmits Msg3 (using timing advance and uplink transmission resources as indicated in Msg2) and monitors the downlink for the confirming Msg4. After receiving the confirming Msg4, the UE monitors the downlink for the broadcast of the requested SI in accordance with the scheduling information for the requested SI, as indicated in the minimum SI. The procedure is illustrated in FIGURE 2, illustrating the message sequence of the Msg3 solution for requesting broadcast/transmission of other SI. The 3GPP agreements also include that the SI provided in a cell may include SI that is valid in other cells than the cell in which the SI is provided, e.g. cells belonging to a certain area, i.e. a SI Area. Such a SI Area is identified by a SI Area ID being periodically broadcast in the minimum SI (in SIB 1) of the cells belonging to the SI Area.

It has also been decided to transmit a broadcast channel, denoted R-PBCH, following a periodic synchronization signal (consisting of the two parts R-PSS and NR- SSS from which the PCI can be derived). Together, the R-PSS+NR-SSS+ R-PBCH form an entity denoted SS Block. Some of the minimum SI will be broadcast on the NR-PBCH, e.g., denoted Master Information Block (MIB or NR-MIB), while the remaining minimum SI (RMSI) will be periodically broadcast on another channel, using a NR-PDCCH/NR- PDSCH structure, i.e. with a scheduling allocation transmitted on the NR-PDCCH, allocating transmission resources on the NR-PDSCH, where the actual RMSI is transmitted.

According to further agreements in 3GPP, information enabling a UE to receive the NR-PDCCH/NR-PDSCH carrying the RMSI should be transmitted on the NR-PBCH.

It has been proposed that it should be possible to use different transmission modes for the NR-PDCCH/NR-PDSCH carrying the RMSI, including e.g. transmission from different TRPs of the same cell (e.g. SFN transmission), omnidirectional transmission (with or without repetition), wide beam (e.g. sector-wide) transmission (with or without repetition), a separate sweep of beams of another width (e.g. semi-wide) than the beams used for the SS Block transmissions and a sweep of beams using the same beams as the ones used for the SS Block transmissions.

In the latter case, the RMSI transmissions may be described as being spatially quasi- co-located (QCL) with the SS Block transmissions, a consequence of which being that the NR-PSS/NR-SSS transmission can be relied on for accurate synchronization to be used when receiving the NR-PDCCH/NR-PDSCH carrying the RMSI. This is however not the case for the other transmission modes, either because different TRPs are used, or because different beamforming configurations are used, resulting in different propagation properties.

One example of a deployments where transmission of the SS Block(s) are unrelated to the beamforming of the NR-PDSCH containing the RMSI is depicted in FIGURE 3 (example depicting that the beamforming and transmission format of the SS Block and the remaining minimum system information may be different). For example, the SS Block may be beam swept using narrow beamforming while the RMSI may be transmitted in wider beams. SUMMARY

According to certain embodiments, a method is provided for use in a wireless device. The method comprises receiving a paging message comprising a system information notification. The method further comprises, in response, performing at least one of storing a current version of system information at the wireless device and applying a previously stored version of system information indicated by the system information notification.

According to certain embodiments, a wireless device comprises memory and processing circuitry. The memory is operable to store instructions. The processing circuitry is operable to execute the instructions. The wireless device is operable to receive a paging message comprising a system information notification. The wireless device is further operable to, in response, perform at least one of store a current version of system information at the wireless device and apply a previously stored version of system information indicated by the system information notification.

According to certain embodiments, a computer program product comprises a non- transitory computer readable medium storing computer readable program code. The computer readable program code comprises program code for receiving a paging message comprising a system information notification and, in response, execute at least one of program code for storing a current version of system information at the wireless device and program code for applying a previously stored version of system information indicated by the system information notification.

The method/wireless device/computer program product may include one or more additional features described below.

In particular embodiments, the system information notification comprises a tag that indicates the previously stored version of system information to be applied by the wireless device. In some embodiments, the method/wireless device/computer program product further comprises determining that the tag received in the paging message matches a previously stored tag associated with the previously stored version of system information.

In particular embodiments, the system information notification indicates a tag associated with the current version of the system information and the current version of the system information is stored at the wireless device with the associated tag. In particular embodiments, wherein at least one of the current system information and the previously stored version of system information comprises remaining minimum system information (RMSI). In some embodiments, the RMSI comprises New Radio- System Information Block 1 (NR-SIB 1).

In particular embodiments, the method/wireless device/computer program product further comprises determining, prior to applying the stored version of system information, that load control parameters restrict the wireless device from accessing a network. The method/wireless device/computer program product further comprises determining, after applying the stored version of system information, that load control parameters no longer restrict the wireless device from accessing the network. In some embodiments, the method/wireless device/computer program product further comprises attempting to access the network before the start of the next modification period boundary and before the next transmission of the stored version of system information remaining minimum system information.

In particular embodiments, the method/wireless device/computer program product further comprises, in response to determining that the current version of system information restricts the wireless device from performing a network access procedure, monitoring the paging channel more frequently than normal. The paging message comprising the system information notification is received while monitoring the paging channel more frequently than normal.

In particular embodiments, the paging message comprising the system information notification includes a flag indicating to immediately apply the previously stored version of system information.

In particular embodiments, the system information notification is a system information update indicating to store the current version of the remaining minimum system information together with the associated tag of this system information before applying the updated remaining minimum system information.

According to certain embodiments, a method is provided for use in a network node. The method comprises sending a paging message to a wireless device. The paging message comprising a system information notification indicating to the wireless device to perform at least one of storing a current version of system information at the wireless device and applying a previously stored version of system information indicated by the system information notification. According to certain embodiments, a network node comprises memory and processing circuitry. The memory is operable to store instructions. The processing circuitry operable to execute the instructions. The network node is operable to send a paging message to a wireless device. The paging message comprising a system information notification indicating to the wireless device to perform at least one of store a current version of system information at the wireless device and apply a previously stored version of system information indicated by the system information notification.

According to certain embodiments, a computer-program product comprises comprising a non-transitory computer readable medium storing computer readable program code. The computer readable program code comprises program code for sending a paging message to a wireless device. The paging message comprising a system information notification indicating to the wireless device to execute at least one of program code for storing a current version of system information at the wireless device and program code for applying a previously stored version of system information indicated by the system information notification.

In particular embodiments, the system information notification comprises a tag that indicates the previously stored version of system information to be applied by the wireless device.

In particular embodiments, the system information notification indicates a tag that the wireless device is to associate with the current version of the system information.

In particular embodiments, the at least one of the current system information and the previously stored system information comprises remaining minimum system information (RMSI). In some embodiments, the RMSI comprises New Radio-System Information Block 1 (NR-SIB 1).

In particular embodiments, the paging message comprising the system information notification includes a flag indicating to immediately apply the previously stored version of system information.

In particular embodiments, the system information notification is a system information update indicating to store the current version of the remaining minimum system information together with the associated tag of this system information before applying the updated remaining minimum system information. In particular embodiments, the paging message comprising the system information notification is sent in response to determining a change in the risk of an overload situation on access resources. In some embodiments, the system information indicates to apply a previously stored version of system information that is more relaxed than the current system information in response to determining the risk of an overload situation on access resources has decreased. In some embodiments, the system information indicates to apply a previously stored version of system information that is more restrictive than the current system information in response to determining the risk of an overload situation on access resources has increased.

Embodiments of the present disclosure may provide one or more technical advantages. As an example, an advantage of certain embodiments enables faster adaptation of load control configuration parameters and random access configuration parameters which result in less actual overload situations and enables a more effective control of the access traffic in the network. As another example, an advantage of certain embodiments provides load control based on signaling the valueTag of the RMSI together with the system information update message on the paging channel. Certain embodiments may include none, some, or all of these advantages. Certain embodiments may include other advantages, as would be understood by a person having ordinary skill in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the disclosed embodiments and their features and advantages, reference is now made to the following description, taking in conjunction with the accompanying drawings, in which:

FIGURE 1 illustrates an example message sequence for requesting system information, according to certain embodiments;

FIGURE 2 illustrates a second example message sequence for requesting system information, according to certain embodiments;

FIGURE 3 illustrates an example deployment where a transmission of SS Blocks is uncoupled from the beamforming of the channel transmitting other system information, according to certain embodiments;

FIGURE 4 is a block diagram illustrating an example of a network, in accordance with certain embodiments;

FIGURE 5 is a block schematic of an example of a wireless device, in accordance with certain embodiments; FIGURE 6 is a block schematic of an example of a network node, in accordance with certain embodiments;

FIGURE 7 is a block schematic of an example of a radio network controller or core network node, in accordance with certain embodiments;

FIGURE 8 is a block schematic of components that may be included in a wireless device, in accordance with certain embodiments;

FIGURE 9 is a block schematic of components that may be included in a network node, in accordance with certain embodiments;

FIGURE 10 illustrates an example of a method for use in a wireless device, according to certain embodiments;

FIGURE 11 illustrates an example of a method for use in a network node, according to certain embodiments;

FIGURES 12 and 13 illustrate examples of signal flows between a network node and a wireless device, in accordance with certain embodiments;

FIGURE 14 illustrates another example of a method for use in a wireless device, according to certain embodiments; and

FIGURE 15 illustrates another example of a method for use in a network node, according to certain embodiments.

DETAILED DESCRIPTION

A problem with the solution for system information distribution as currently defined for NR is that there is no fast method specified to change the system information of the serving cell.

In NR, potentially billions of low cost UEs may be deployed, e.g., for M-MTC and C-MTC use-cases. This large number of users can easily overload the PRACH resources with random access attempts, and in the worst case this can totally block any UE from accessing the network. To avoid this, NR will make use of load control parameters that are broadcasted in the remaining minimum system information.

In NR (as in LTE), a Paging message may inform UEs in an idle state, such as RRC IDLE, an inactive state, such as RRC INACTIVE, and in a connected state, such as RRC CONNECTED about a system information change. If the UE receives a Paging message including a systemlnfoModification message, the UE may determine that the system information will change at the next modification period boundary. Due to network restrictions, the system modification period needs to be several paging cycles long and thus this process in NR is not fast enough to efficiently track the expected variations in traffic that requires load control. For example, the system modification period may be significantly longer than the expected variation time on which load control may change.

The result of this slow adaption of load control is that there will be situations where high priority traffic is being blocked by low priority traffic. For example, if load control is implemented due to an increase of load on the network, low priority wireless devices may not adjust their behavior until the next modification period boundary, which continue to prevent high priority traffic until that boundary. Also, the thresholds for returning to normal operation without load control will need to be set very conservative (e.g., using long timers before triggering) in an attempt to avoid the above-described problem. This results in suboptimal performance. Embodiments of the present disclosure may provide solutions to these and other problems.

According to certain embodiments, a method is disclosed for use in a UE wanting to access a network for which the current configuration of the load control parameters is preventing access. The method comprises the following actions:

- (optionally) monitoring the paging channel more frequently than normal;

- receiving a system information change notification message in the paging message containing a valueTag associated with a previously stored version of the remaining minimum system information (NR-SIB l) and (optionally) a flag indicating that this system information change takes effect immediately;

- immediately applying the associated stored version of the remaining system information (NR-SIBl);

- determining that the load control parameters no longer restricts the UE from accessing the network;

- attempting to access the network before the start of the next modification period boundary and before the next transmi ssi on of the remaining minimum system information.

According to certain embodiments, when the UE receives a systemlnformationUpdate paging message it stores the current version of the remaining minimum system information (e.g. NR-SIBl) together with the associated valueTag of this system information version (e.g. systemlnformationValueTagSIBl).

In some embodiments, the systemlnformationUpdate paging message contains

- a valueTag associated with a previously stored version of the remaining system information (NR-SIBl); and - a flag indicating that this system information change takes effect immediately (as described in [1]), then

the UE immediately applies the stored version of the remaining system information (NR-SIB 1).

In certain embodiments, a UE that has stored a version of the RMSI (previously received) and that finds that the current version of the RMSI restricts it from performing an initial access may start to monitor the paging channel more frequently than normal, e.g., by reducing the amount of time between monitoring the paging channel or increasing the number of times the paging channel is monitored in a time period. As soon as it receives a paging message with a valueTag associated with the stored RMSI, it can apply this stored system information and access the system.

In certain embodiments, the a UE, when it receives a systemlnformationUpdate paging message, storing the current version of the remaining minimum system information (e.g. R-SIB 1) together with the associated valueTag of this system information (e.g. systemlnformationValueTagSIB l) before applying the updated remaining minimum system information.

As an example, the disclosure contemplates a base station performing the steps of

- detecting an increased risk of an overload situation on the access resources (e.g., PRACH/RAR)

- changing the RMSI to a previous used configuration with a valueTag that is still valid (e.g., it has not timed out) characterized by that the load control parameters become more restrictive and/or the amount of random access resources are increased in order to reduce said overload risk

- signaling on the paging channel that new remaining minimum system information is available together with the associated valueTag and an optional validity indicator (indicating if the change is effective immediately or at the next modification period );

In some embodiments, the base station may perform the steps of

- detecting a decreased risk of an overload situation on the access resources (e.g., PRACH/RAR)

- changing the RMSI to a previous used configuration with a valueTag that is still valid (e.g., it has not timed out) characterized by that the load control parameters become more relaxed (e.g. no access barring) and/or the amount of random access resources are reduced (e.g. back to a normal configuration) - signaling on the paging channel that new remaining minimum system information is available together with the associated valueTag and an optional validity indicator (indicating if the change is effective immediately or at the next modification period).

FIGURE 4 is a block diagram illustrating an embodiment of a network 100, in accordance with certain embodiments. Network 100 includes one or more UE(s) 110 (which may be interchangeably referred to as wireless devices 1 10) and one or more network node(s) 115 (which may be interchangeably referred to as gNBs 115). UEs 110 may communicate with network nodes 1 15 over a wireless interface. For example, a UE 110 may transmit wireless signals to one or more of network nodes 115, and/or receive wireless signals from one or more of network nodes 115. The wireless signals may contain voice traffic, data traffic, control signals, and/or any other suitable information. In some embodiments, an area of wireless signal coverage associated with a network node 115 may be referred to as a cell 125. In some embodiments, UEs 1 10 may have device-to-device (D2D) capability. Thus, UEs 110 may be able to receive signals from and/or transmit signals directly to another UE.

In certain embodiments, network nodes 1 15 may interface with a radio network controller. The radio network controller may control network nodes 1 15 and may provide certain radio resource management functions, mobility management functions, and/or other suitable functions. In certain embodiments, the functions of the radio network controller may be included in network node 1 15. The radio network controller may interface with a core network node. In certain embodiments, the radio network controller may interface with the core network node via an interconnecting network 120. Interconnecting network 120 may refer to any interconnecting system capable of transmitting audio, video, signals, data, messages, or any combination of the preceding. Interconnecting network 120 may include all or a portion of a public switched telephone network (PSTN), a public or private data network, a local area network (LAN), a metropolitan area network (MAN), a wide area network (WAN), a local, regional, or global communication or computer network such as the Internet, a wireline or wireless network, an enterprise intranet, or any other suitable communication link, including combinations thereof.

In some embodiments, the core network node may manage the establishment of communication sessions and various other functionalities for UEs 110. UEs 110 may exchange certain signals with the core network node using the non-access stratum (NAS) layer. In non-access stratum signaling, signals between UEs 110 and the core network node may be transparently passed through the radio access network. In certain embodiments, network nodes 1 15 may interface with one or more network nodes over an internode interface.

As described above, example embodiments of network 100 may include one or more wireless devices 110, and one or more different types of network nodes capable of communicating (directly or indirectly) with wireless devices 110.

In some embodiments, the non-limiting term UE is used. UEs 110 described herein can be any type of wireless device capable of communicating with network nodes 1 15 or another UE over radio signals. UE 110 may also be a radio communication device, target device, D2D UE, NB-IoT device, MTC UE or UE capable of machine-to-machine communication (M2M), low-cost and/or low-complexity UE, a sensor equipped with UE, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles, Customer Premises Equipment (CPE), etc.

Also, in some embodiments generic terminology, "radio network node" (or simply "network node") is used. It can be any kind of network node, which may comprise a gNB, base station (BS), radio base station, Node B, base station (BS), multi-standard radio (MSR) radio node such as MSR BS, evolved Node B (eNB), network controller, radio network controller (RNC), base station controller (BSC), relay node, relay donor node controlling relay, base transceiver station (BTS), access point (AP), radio access point, transmission points, transmission nodes, Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), Multi-cell/multicast Coordination Entity (MCE), core network node (e.g., MSC, MME, etc.), O&M, OSS, SON, positioning node (e.g., E-SMLC), MDT, or any other suitable network node.

The terminology such as network node and UE should be considered non-limiting and, in particular, does not imply a certain hierarchical relation between the two; in general, "eNodeB" could be considered as device 1 and "UE" device 2, and these two devices communicate with each other over some radio channel.

Example embodiments of UE 1 10, network nodes 1 15, and other network nodes (such as radio network controller or core network node) are described in more detail below with respect to FIGURES 5-9.

Although FIGURE 4 illustrates a particular arrangement of network 100, the present disclosure contemplates that the various embodiments described herein may be applied to a variety of networks having any suitable configuration. For example, network 100 may include any suitable number of UEs 110 and network nodes 115, as well as any additional elements suitable to support communication between UEs or between a UE and another communication device (such as a landline telephone). Furthermore, although certain embodiments may be described as implemented in an R or 5G network, the embodiments may be implemented in any appropriate type of telecommunication system supporting any suitable communication and using any suitable components, and are applicable to any radio access technology (RAT) or multi-RAT systems in which a UE receives and/or transmits signals (e.g., data). For example, the various embodiments described herein may be applicable to IoT, B-IoT, LTE, LTE-Advanced, UMTS, HSPA, GSM, cdma2000, WCDMA, WiMax, UMB, WiFi, another suitable radio access technology, or any suitable combination of one or more radio access technologies.

FIGURE 5 is a block schematic of an exemplary wireless device 110, in accordance with certain embodiments. Wireless device 1 10 may refer to any type of wireless device communicating with a node and/or with another wireless device in a cellular or mobile communication system. Examples of wireless device 1 10 include a mobile phone, a smart phone, a PDA (Personal Digital Assistant), a portable computer (e.g., laptop, tablet), a sensor, a modem, an MTC device / machine-to-machine (M2M) device, laptop embedded equipment (LEE), laptop mounted equipment (LME), USB dongles, a D2D capable device, or another device that can provide wireless communication. A wireless device 1 10 may also be referred to as UE, a station (STA), a device, or a terminal in some embodiments. Wireless device 110 includes transceiver 710, processing circuitry 720, and memory 730. In some embodiments, transceiver 710 facilitates transmitting wireless signals to and receiving wireless signals from network node 1 15 (e.g., via antenna 740), processing circuitry 720 (e.g., which may include one or more processors) executes instructions to provide some or all of the functionality described above as being provided by wireless device 110, and memory 730 stores the instructions executed by processing circuitry 720.

Processing circuitry 720 may include any suitable combination of hardware and software implemented in one or more modules to execute instructions and manipulate data to perform some or all of the described functions of wireless device 1 10, such as the functions of UE 110 (i.e., wireless device 110) described in relation to any of sections 3, 4, and 6 herein. For example, in general, processing circuitry may save a current version of system information and/or apply a previously stored version of system information based on a system information notification (e.g., system information change notification, system information modification, or system information update) received in a paging message from a network node 1 15. In some embodiments, processing circuitry 720 may include, for example, one or more computers, one or more central processing units (CPUs), one or more microprocessors, one or more applications, one or more application specific integrated circuits (ASICs), one or more field programmable gate arrays (FPGAs) and/or other logic.

Memory 730 is generally operable to store instructions, such as a computer program, software, an application including one or more of logic, rules, algorithms, code, tables, etc. and/or other instructions capable of being executed by a processor. Examples of memory 730 include computer memory (for example, Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (for example, a hard disk), removable storage media (for example, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or or any other volatile or non-volatile, non-transitory computer-readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by processor 1020.

Other embodiments of wireless device 110 may optionally include additional components beyond those shown in FIGURE 5 that may be responsible for providing certain aspects of the wireless device's functionality, including any of the functionality described above and/or any additional functionality (including any functionality necessary to support the solution described above). As just one example, wireless device 1 10 may include input devices and circuits, output devices, and one or more synchronization units or circuits, which may be part of the processing circuitry 720. Input devices include mechanisms for entry of data into wireless device 1 10. For example, input devices may include input mechanisms, such as a microphone, input elements, a display, etc. Output devices may include mechanisms for outputting data in audio, video, and/or hard copy format. For example, output devices may include a speaker, a display, etc.

FIGURE 6 is a block schematic of an exemplary network node 115, in accordance with certain embodiments. Network node 1 15 may be any type of radio network node or any network node that communicates with a UE and/or with another network node. Examples of network node 115 include an gNB, eNodeB, a node B, a base station, a wireless access point (e.g., a Wi-Fi access point), a low power node, a base transceiver station (BTS), relay, donor node controlling relay, transmission points, transmission nodes, remote RF unit (RRU), remote radio head (RRH), multi-standard radio (MSR) radio node such as MSR BS, nodes in distributed antenna system (DAS), O&M, OSS, SON, positioning node (e.g., E- SMLC), MDT, or any other suitable network node. Network nodes 1 15 may be deployed throughout network 100 as a homogenous deployment, heterogeneous deployment, or mixed deployment. A homogeneous deployment may generally describe a deployment made up of the same (or similar) type of network nodes 115 and/or similar coverage and cell sizes and inter-site distances. A heterogeneous deployment may generally describe deployments using a variety of types of network nodes 115 having different cell sizes, transmit powers, capacities, and inter-site distances. For example, a heterogeneous deployment may include a plurality of low-power nodes placed throughout a macro-cell layout. Mixed deployments may include a mix of homogenous portions and heterogeneous portions.

Network node 1 15 may include one or more of transceiver 810, processing circuitry 820 (e.g., which may include one or more processors), memory 830, and network interface 840. In some embodiments, transceiver 810 facilitates transmitting wireless signals to and receiving wireless signals from wireless device 1 10 (e.g., via antenna 850), processing circuitry 820 executes instructions to provide some or all of the functionality described above as being provided by a network node 115, memory 830 stores the instructions executed by processing circuitry 820, and network interface 840 communicates signals to backend network components, such as a gateway, switch, router, Internet, Public Switched Telephone Network (PSTN), core network nodes or radio network controllers 130, etc.

Processing circuitry 820 may include any suitable combination of hardware and software implemented in one or more modules to execute instructions and manipulate data to perform some or all of the described functions of network node 1 15, such as those described in relation to any of sections 3, 4, or 6 herein. For example, in general, processing circuitry 820 may cause network node to send a paging message that includes a system information notification. In certain embodiments, the system information notification may be sent in response to detecting a change in the risk of an overload situation on access resources and may indicate that the wireless device 1 10 is to apply a previously stored version of system information. In some embodiments, processing circuitry 820 may include, for example, one or more computers, one or more central processing units (CPUs), one or more microprocessors, one or more applications, and/or other logic.

Memory 830 is generally operable to store instructions, such as a computer program, software, an application including one or more of logic, rules, algorithms, code, tables, etc. and/or other instructions capable of being executed by a processor. Examples of memory 830 include computer memory (for example, Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (for example, a hard disk), removable storage media (for example, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or or any other volatile or non-volatile, non-transitory computer-readable and/or computer-executable memory devices that store information.

In some embodiments, network interface 840 is communicatively coupled to processing circuitry 820 and may refer to any suitable device operable to receive input for network node 115, send output from network node 115, perform suitable processing of the input or output or both, communicate to other devices, or any combination of the preceding. Network interface 840 may include appropriate hardware (e.g., port, modem, network interface card, etc.) and software, including protocol conversion and data processing capabilities, to communicate through a network.

Other embodiments of network node 115 may include additional components beyond those shown in FIGURE 6 that may be responsible for providing certain aspects of the radio network node's functionality, including any of the functionality described above and/or any additional functionality (including any functionality necessary to support the solutions described above). The various different types of network nodes may include components having the same physical hardware but configured (e.g., via programming) to support different radio access technologies, or may represent partly or entirely different physical components.

FIGURE 7 is a block schematic of an exemplary radio network controller or core network node 130, in accordance with certain embodiments. Examples of network nodes can include a mobile switching center (MSC), a serving GPRS support node (SGSN), a mobility management entity (MME), a radio network controller (RNC), a base station controller (BSC), and so on. The radio network controller or core network node 130 includes processing circuitry 920 (e.g., which may include one or more processors), memory 930, and network interface 940. In some embodiments, processing circuitry 920 executes instructions to provide some or all of the functionality described above as being provided by the network node, memory 930 stores the instructions executed by processing circuitry 920, and network interface 940 communicates signals to any suitable node, such as a gateway, switch, router, Internet, Public Switched Telephone Network (PSTN), network nodes 115, radio network controllers or core network nodes 130, etc.

Processing circuitry 920 may include any suitable combination of hardware and software implemented in one or more modules to execute instructions and manipulate data to perform some or all of the described functions of the radio network controller or core network node 130. In some embodiments, processing circuitry 920 may include, for example, one or more computers, one or more central processing units (CPUs), one or more microprocessors, one or more applications, and/or other logic.

Memory 930 is generally operable to store instructions, such as a computer program, software, an application including one or more of logic, rules, algorithms, code, tables, etc. and/or other instructions capable of being executed by a processor. Examples of memory 930 include computer memory (for example, Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (for example, a hard disk), removable storage media (for example, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or or any other volatile or non-volatile, non-transitory computer-readable and/or computer-executable memory devices that store information.

In some embodiments, network interface 940 is communicatively coupled to processing circuitry 920 and may refer to any suitable device operable to receive input for the network node, send output from the network node, perform suitable processing of the input or output or both, communicate to other devices, or any combination of the preceding. Network interface 940 may include appropriate hardware (e.g., port, modem, network interface card, etc.) and software, including protocol conversion and data processing capabilities, to communicate through a network.

Other embodiments of the network node may include additional components beyond those shown in FIGURE 7 that may be responsible for providing certain aspects of the network node's functionality, including any of the functionality described above and/or any additional functionality (including any functionality necessary to support the solution described above).

FIGURE 8 is a block schematic of an exemplary wireless device 110, in accordance with certain embodiments. Wireless device 1 10 may include one or more modules. For example, wireless device 110 may include a determining module 1010, a communication module 1020, a receiving module 1030, an input module 1040, a display module 1050, and/or any other suitable modules. Wireless device 110 may perform the methods related to storing or applying system information described herein.

Determining module 1010 may perform the processing functions of wireless device 1 10 (e.g., as described in sections 3, 4, and/or 6). As one example, determining module 1010 may determine to store a current version of system information and/or to apply a previously stored version of system information based on a system information notification that wireless device 1 10 receives in a paging message. Determining module 1010 may include or be included in one or more processors, such as processing circuitry 720 described above in relation to FIGURE 5. Determining module 1010 may include analog and/or digital circuitry configured to perform any of the functions of determining module 1010 and/or processing circuitry 720 described above. The functions of determining module 1010 described above may, in certain embodiments, be performed in one or more distinct modules.

Communication module 1020 may perform the transmission functions of wireless device 1 10. As one example, communication module 1020 may communicate access attempts to network node 1 15. Communication module 1020 may include circuitry configured to wirelessly transmit messages and/or signals. In particular embodiments, communication module 1020 may receive messages and/or signals for transmission from determining module 1010. In certain embodiments, the functions of communication module 1020 described above may be performed in one or more distinct modules.

Receiving module 1030 may perform the receiving functions of wireless device 110. As one example, receiving module 1030 may receive a paging message from network node 1 15. Receiving module 1030 may include a receiver and/or a transceiver, such as transceiver 710 described above in relation to FIGURE 5. Receiving module 1030 may include circuitry configured to wirelessly receive messages and/or signals. In particular embodiments, receiving module 1030 may communicate received messages and/or signals to determining module 1010.

Input module 1040 may receive user input intended for wireless device 1 10. For example, the input module may receive key presses, button presses, touches, swipes, audio signals, video signals, and/or any other appropriate signals. The input module may include one or more keys, buttons, levers, switches, touchscreens, microphones, and/or cameras. The input module may communicate received signals to determining module 1010. Input module 1040 may be optional in certain embodiments.

Display module 1050 may present signals on a display of wireless device 110. Display module 1050 may include the display and/or any appropriate circuitry and hardware configured to present signals on the display. Display module 1050 may receive signals to present on the display from determining module 1010. Display module 1050 may be optional in certain embodiments. Determining module 1010, communication module 1020, receiving module 1030, input module 1040, and display module 1050 may include any suitable configuration of hardware and/or software. Wireless device 110 may include additional modules beyond those shown in FIGURE 8 that may be responsible for providing any suitable functionality, including any of the functionality described above and/or any additional functionality (including any functionality necessary to support the various solutions described herein).

FIGURE 9 is a block schematic of an exemplary network node 115, in accordance with certain embodiments. Network node 115 may include one or more modules. For example, network node 115 may include determining module 11 10, communication module 1 120, receiving module 1130, and/or any other suitable modules. In some embodiments, one or more of determining module 1 110, communication module 1120, receiving module 1130, or any other suitable module may be implemented using one or more processors, such as processing circuitry 820 described above in relation to FIGURE 6. In certain embodiments, the functions of two or more of the various modules may be combined into a single module. Network node 1 15 may perform the methods described with respect to any of sections 3, 4, or 6 as being performed by a network node (such as a gNB).

Determining module 1 110 may perform the processing functions of network node 1 15. As one example, determining module 1 110 may determine, based on the risk of an overload situation on access resources, to send wireless device 110 a paging message indicating to apply a previously stored version of system information. Determining module 1 110 may include or be included in one or more processors, such as processing circuitry 820 described above in relation to FIGURE 6. Determining module 11 10 may include analog and/or digital circuitry configured to perform any of the functions of determining module 1 110 and/or processing circuitry 820 described above. The functions of determining module 1 110 may, in certain embodiments, be performed in one or more distinct modules. For example, in certain embodiments some of the functionality of determining module 11 10 may be performed by an allocation module.

Communication module 1120 may perform the transmission functions of network node 1 15. As one example, communication module 1 120 may send the paging message to wireless device 110. Communication module 1 120 may transmit messages to one or more of wireless devices 110. Communication module 1 120 may include a transmitter and/or a transceiver, such as transceiver 810 described above in relation to FIGURE 6. Communication module 1120 may include circuitry configured to wirelessly transmit messages and/or signals. In particular embodiments, communication module 1 120 may receive messages and/or signals for transmission from determining module 1 110 or any other module.

Receiving module 1130 may perform the receiving functions of network node 115. As one example, receiving module 1130 may receive PRACH messages from wireless devices 1 10. Receiving module 1130 may receive any suitable information from a wireless device. Receiving module 1 130 may include a receiver and/or a transceiver, such as transceiver 810 described above in relation to FIGURE 6. Receiving module 1130 may include circuitry configured to wirelessly receive messages and/or signals. In particular embodiments, receiving module 1 130 may communicate received messages and/or signals to determining module 1 110 or any other suitable module.

Determining module 11 10, communication module 1 120, and receiving module 1 130 may include any suitable configuration of hardware and/or software. Network node 1 15 may include additional modules beyond those shown in FIGURE 9 that may be responsible for providing any suitable functionality, including any of the functionality described above and/or any additional functionality (including any functionality necessary to support the various solutions described herein).

EXAMPLE EMBODIMENTS

1. A method for use in a wireless device, the method comprising:

receiving a paging message comprising a system information notification and, in response, performing at least one of:

storing a current version of system information at the wireless device; and/or applying a previously stored version of system information indicated by the system information notification.

2. The method of example embodiment 1, wherein the system information notification comprises a tag that indicates the previously stored version of system information to be applied by the wireless device.

2b. The method of example embodiment 2, further comprising determining that the tag received in the paging message matches a previously stored tag associated with the previously stored version of system information. 3. The method of any of example embodiments 1-2, wherein the system information notification indicates a tag associated with the current version of the system information and the current version of the system information is stored at the wireless device with the associated tag.

4. The method of any of example embodiments 1-3, wherein the (current and/or previously stored) system information comprises remaining minimum system information (RMSI).

5. The method of example embodiment 4, wherein the RMSI comprises New Radio- System Information Block 1 (NR-SIB 1).

6. The method of any of example embodiments 1-5, further comprising:

determining, prior to applying the stored version of system information, that load control parameters restrict the wireless device from accessing a network; and

determining, after applying the stored version of system information, that load control parameters no longer restrict the wireless device from accessing the network.

7. The method of example embodiment 6, further comprising:

attempting to access the network before the start of the next modification period boundary and before the next transmission of the remaining minimum system information.

8. The method of any of example embodiments 1-7, wherein the paging message comprising the system information notification is received while monitoring the paging channel more frequently than normal, the paging channel monitored more frequently than normal in response to determining that the current version of system information restricts the wireless device from performing an initial access.

9. The method of any of example embodiments 1-8, wherein the paging message comprising the system information notification includes a flag indicating to immediately apply the previously stored version of system information. 10. The method of any of example embodiments 1-9, wherein the system information notification is a system information update indicating to store the current version of the remaining minimum system information (e.g. NR-SIB 1) together with the associated valueTag of this system information (e.g. systemlnformationValueTagSIBl) before applying the updated remaining minimum system information.

1 1. A wireless device comprising memory operable to store instructions and processing circuitry operable to execute the instructions, whereby the wireless device is operable to perform any of the methods of example embodiments 1-10.

12. A computer program product comprising a non-transitory computer readable medium storing computer readable program code, the computer readable program code comprises program code for performing any of the methods of example embodiments 1-10.

13. A method for use in network node, the method comprising:

sending a paging message to a wireless device, the paging message comprising a system information notification indicating to the wireless device to perform at least one of: storing a current version of system information at the wireless device; and/or applying a previously stored version of system information indicated by the system information notification.

14. The method of example embodiment 13, wherein the system information notification comprises a tag that indicates the previously stored version of system information to be applied by the wireless device.

15. The method of any of example embodiments 13-15, wherein the system information notification indicates a tag that the wireless device is to associate with the current version of the system information.

16. The method of any of example embodiments 13-16, wherein the (current and/or previously stored) system information comprises remaining minimum system information (RMSI). 17. The method of example embodiment 16, wherein the RMSI comprises New Radio-System Information Block 1 (NR-SIB 1).

18. The method of any of example embodiments 13-17, wherein the paging message comprising the system information notification includes a flag indicating to immediately apply the previously stored version of system information.

19. The method of any of example embodiments 13-18, wherein the system information notification is a system information update indicating to store the current version of the remaining minimum system information (e.g. NR-SIB 1) together with the associated valueTag of this system information (e.g. systemlnformationValueTagSIBl) before applying the updated remaining minimum system information.

20. The method of any of example embodiments 13-19, wherein the paging message comprising the system information notification is sent in response to determining a change in the risk of an overload situation on access resources.

21. The method of example embodiment 20, wherein the system information indicates to apply a previously stored version of system information that is more relaxed than the current system information in response to determining the risk of an overload situation on access resources has decreased.

22. The method of example embodiment 20, wherein the system information indicates to apply a previously stored version of system information that is more restrictive than the current system information in response to determining the risk of an overload situation on access resources has increased.

23. A network node comprising memory operable to store instructions and processing circuitry operable to execute the instructions, whereby the network node is operable to perform any of the methods of example embodiments 13-22.

24. A computer program product comprising a non-transitory computer readable medium storing computer readable program code, the computer readable program code comprises program code for performing any of the methods of example embodiments 13-22.

FIGURE 10 illustrates another example of a method for use in a wireless device, according to certain embodiments. The method comprises (1) receiving a first paging message comprising a system information update and a first tag; (2) storing a current version of system information (e.g., RMSI) at the wireless device as a first stored version of system information associated with the first tag; (3) applying a second version of system information as the current version of system information, (4) determining that load control parameters in the second version of system information restrict the wireless device from performing an initial access; (5) monitoring the paging channel more frequently than normal; (6) receiving a second paging message comprising a system information change and the first tag; (7) applying the previously stored first version of system information associated with the first tag; (8) determining that load control parameters no longer restrict the wireless device from accessing the network; and/or (9) attempting to access the network (e.g., before the start of the next modification period boundary and before the next transmission of the remaining minimum system information). Certain embodiments may comprise more or fewer actions, and the actions may be performed in any suitable order.

FIGURE 1 1 illustrates another example of a method for use in a network node, according to certain embodiments. The method comprises (1) sending a first paging message comprising a system information update and a first tag, the first paging message indicating for a wireless device to store a current version of system information (e.g., RMSI) at the wireless device as a first stored version of system information associated with the first tag; (2) indicating for the wireless device to apply a second version of system information as the current version of system information; (3) determining a change in the risk of an overload situation on access resources; (4) sending a second paging message compiling a system information change and the first tag, the second paging message indicating for the wireless device to apply the previously stored first version of system information associated with the first tag; and/or (5) receiving an access attempt from the wireless device (e.g., before the start of the next modification period boundary and before the next transmission of the remaining minimum system information). Certain embodiments may comprise more or fewer actions, and the actions may be performed in any suitable order.

FIGURES 12 and 13 illustrate examples of signal flows between a network node 1 15 and a wireless device 1 10, in accordance with certain embodiments. In FIGURE 12, network node 115 sends a Paging Message comprising a System Information Update Notification and Tag, and wireless device 110 responds by storing a current version of system information with the associated tag received in the paging message. In FIGURE 13, network node 1 15 sends a Paging Message comprising a System Information Change Notification and Tag, and wireless device 1 10 responds by applying a previously stored version of system information associated with the tag received in the paging message.

FIGURE 14 illustrates another example method 1400 for use in a wireless device. Method 1400 may start at step 1410, in which a paging message is received at the wireless device. The paging message received includes a system information notification. In response, the wireless device may perform one or more of steps 1420 and 1430. At step 1420, a current version of system information ("SI A") is stored at the wireless device. In certain embodiments, the system information notification indicates a tag ("tag A") associated with the current version of the system information and the current version of the system information is stored at the wireless device with the associated tag. In this manner, SI A may be updated at wireless device and associated with tag A for subsequent use at the wireless device based on the received paging message, which may be sent prior to the next modification period boundary and separately from the regular broadcast system information update. At step 1430, a previously stored version of system information ("SI B") indicated by the system information notification is applied. In certain embodiments, the system information notification comprises a tag (e.g., "tag B") that indicates the previously stored version of system information to be applied by the wireless device. In certain embodiments, method 1400 may include additional and/or optional steps. For example, method 1400 may further include step 1425. At step 1425, the wireless device determines that the tag received in the paging message matches a previously stored tag, tag B, associated with the previously stored version of system information, SI B. In this manner, the wireless device may determine, via the system information notification, to apply SI B based on the paging message. Further, this allows the paging message to be less resource intensive by only requiring the transmittal of tag B without resending the entirety of SI B.

In certain embodiments, at least one of the current system information and the previously stored version of system information comprises remaining minimum system information (RMSI). In some embodiments, the RMSI comprises New Radio-System Information Block 1 (NR-SIB l). The RMSI and/or the NR-SIB l may include one or more load control parameters. The load control parameters may indicate to the wireless device if and/or when the wireless device is barred from attempted to access the network, e.g., when it may attempt random access. Accordingly, the wireless device may determine which system information to use or apply based on the paging message received, e.g., as in step 1410.

In certain embodiments, method 1400 further includes the step of determining, prior to applying the stored version of system information, that load control parameters restrict the wireless device from accessing a network. For example, the wireless device may receive system information that indicates that the wireless device is restricted from accessing the network. Subsequently, the wireless device may determine, e.g., in response to the paging message, to apply a stored version of the system information, which may have different load control parameters. For example, the wireless device may determine, after applying the stored version of system information, that load control parameters no longer restrict the wireless device from accessing the network.

In some embodiments, method 1400 may further include the step of attempting to access the network before the start of the next modification period boundary and before the next transmission of the stored version of system information remaining minimum system information. In this manner, if the load conditions have changed, the wireless device may adapt more quickly to the new load control parameters and may access the network prior to receiving the updated system information.

In certain embodiments, the wireless device may monitor the paging channel for paging messages, which may cause the wireless device to carry out one or more of steps 1420 and 1430. In some embodiments, method 1400 may further comprise monitoring the paging channel more frequently than normal in response to determining that the current version of system information restricts the wireless device from performing a network access procedure. In this manner, the wireless device may have less delay in determining when the restrictions have changed, thereby allowing the wireless device to access the network without waiting for the next modification period boundary. In some embodiments, the paging message comprising the system information notification is received while monitoring the paging channel more frequently than normal.

FIGURE 15 illustrates another example method 1500 for use in a network node. Method 1500 may begin at step 1510, wherein a paging message is sent to a wireless device, such as the wireless device described above in reference to method 1400. The paging message comprises a system information notification indicating to the wireless device to perform at least one of steps 1520 and 1530. At step 1520, the current version of system information is stored at the wireless device, as described above in reference to step 1420. At step 1530, a previously stored version of system information indicated by the system information notification is applied, as described above in reference to step 1530. In this manner, a network node may cause the wireless device to adapt the applied system information more quickly, e.g., prior to the next modification period boundary.

In certain embodiments, one or more steps of the methods described above may be carried out using one or more components of wireless device 110 or network node 1 15. For example, one or more receiving and sending steps may be carried out using transceiver 710 of wireless device 110 and/or transceiver 810 of network node 115. As another example, one or more determining or applying steps may be carried out using processing circuitry 720 and/or memory 730 of wireless device 110 and/or processing circuitry 820 and/or memory 830 of network node 115. In this manner, one or more of the methods described above may be carried out by wireless device 110 or network node 115, each of which may be used as a transmitter and/or a receiver.

Modifications, additions, or omissions may be made to the systems and apparatuses described herein without departing from the scope of the disclosure. The components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses may be performed by more, fewer, or other components. Additionally, operations of the systems and apparatuses may be performed using any suitable logic comprising software, hardware, and/or other logic. As used in this document, "each" refers to each member of a set or each member of a subset of a set.

Modifications, additions, or omissions may be made to the methods described herein without departing from the scope of the disclosure. The methods may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order.

Although this disclosure has been described in terms of certain embodiments, alterations and permutations of the embodiments will be apparent to those skilled in the art. Accordingly, the above description of the embodiments does not constrain this disclosure. Other changes, substitutions, and alterations are possible without departing from the spirit and scope of this disclosure.