WO2024040441A1

WO2024040441A1 - Methods, devices, and medium for communication

Info

Publication number: WO2024040441A1
Application number: PCT/CN2022/114311
Authority: WO
Inventors: Lei Chen; Gang Wang
Original assignee: Nec Corporation
Priority date: 2022-08-23
Filing date: 2022-08-23
Publication date: 2024-02-29

Abstract

Example embodiments of the present disclosure relate to methods, devices, and computer storage medium for communication. A terminal device in a low power mode monitors a first signal from a network device; monitors a second signal from the network device, the second signal is at least a part of a low power wake up signal; in accordance with a determination that the first signal is detected and the second signal is detected, wakes up from the low power mode; or in accordance with a determination that the first signal is detected and the second signal is not detected, stays in the low power mode. As such, two signals are used the terminal device to determine whether to wake up. Specifically, the terminal device may determine whether a miss-detection of the second signal is happened based on the first signal, and thus a wrong determination on whether to wake up may be avoided.

Description

METHODS, DEVICES, AND MEDIUM FOR COMMUNICATION

FIELD

Example embodiments of the present disclosure generally relate to the field of communication techniques and in particular, to methods, devices, and a computer readable medium for communication.

BACKGROUND

Several technologies have been proposed for power saving of a terminal device. For example, a user equipment (UE) may enter to a radio resource control (RRC) idle/inactive state to reduce power consumption. However, it is still critical for power limited devices, e.g., the Internet of Things (IoT) devices, wearable devices, etc., since periodic paging monitoring and measurement consume considerable power at UE side even in RRC idle/inactive state. Therefore, it is beneficial for UE to further reduce the power consumption.

SUMMARY

In general, example embodiments of the present disclosure provide methods, devices and a computer storage medium for communication.

In a first aspect, there is provided a method of communication. The method comprises: monitoring, at a terminal device in a low power mode, a first signal from a network device; monitoring a second signal from the network device, the second signal being at least a part of a low power wake up signal; in accordance with a determination that the first signal is detected and the second signal is detected, waking up from the low power mode; or in accordance with a determination that the first signal is detected and the second signal is not detected, staying in the low power mode.

In a second aspect, there is provided a method of communication. The method comprises: generating, at a network device, a first signal for a plurality of terminal devices in a low power mode; determining whether to wake up one of the plurality of terminal devices; in accordance with a determination that the terminal device is needed to wake up, generating a second signal for the one of the plurality of terminal devices, the second signal being a low power wake up signal; transmitting the first signal to the plurality of terminal devices; and transmitting the second signal to the one of the plurality of terminal devices.

In a third aspect, there is provided a terminal device. The terminal device comprises a processor and a memory. The memory is coupled to the processor and stores instructions thereon. The instructions, when executed by the processor, cause the terminal device to perform the method according to the first aspect above.

In a fourth aspect, there is provided a network device. The network device comprises a processor and a memory. The memory is coupled to the processor and stores instructions thereon. The instructions, when executed by the processor, cause the network device to perform the method according to the second aspect above.

In a fifth aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to the first aspect or the second aspect above.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some example embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

FIG. 1 illustrates an example communication system in which some embodiments of the present disclosure can be implemented;

FIG. 2A illustrates a schematic diagram of resources occupied by an LP signal which can be used in some example embodiments of the present disclosure;

FIGS. 2B-2C illustrate schematic diagrams of OOK symbols which can be used in some example embodiments of the present disclosure;

FIG. 3 illustrates a signalling chart illustrating communication process in accordance with some embodiments of the present disclosure;

FIGS. 4A-4C illustrate some example schematic diagrams of the time resources of the first signal and the second signal according to some embodiments of the present disclosure;

FIGS. 5A-5B illustrate some example schematic diagrams of time durations of the first signal and the second signal according to some embodiments of the present disclosure;

FIG. 6 illustrates a schematic diagram of multiple candidate signals including the second signal according to some embodiments of the present disclosure;

FIG. 7 illustrates a schematic diagram of multiple occasions for a wake up signal according to some embodiments of the present disclosure;

FIG. 8 illustrates a flowchart of an example method in accordance with some embodiments of the present disclosure;

FIG. 9 illustrates a flowchart of an example method in accordance with some embodiments of the present disclosure; and

FIG. 10 illustrates a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

In some examples, values, procedures, or apparatus are referred to as “best, ” “lowest, ” “highest, ” “minimum, ” “maximum, ” or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR) , Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) , 5.5G, 5G-Advanced networks, or the sixth generation (6G) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

As used herein, the term “terminal device” refers to any device having wireless or wired communication capabilities. Examples of terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Ultra-reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, devices for Integrated Access and Backhaul (IAB) , Space borne vehicles or Air borne vehicles in Non-terrestrial networks (NTN) including Satellites and High Altitude Platforms (HAPs) encompassing Unmanned Aircraft Systems (UAS) , eXtended Reality (XR) devices including different types of realities such as Augmented Reality (AR) , Mixed Reality (MR) and Virtual Reality (VR) , the unmanned aerial vehicle (UAV) commonly known as a drone which is an aircraft without any human pilot, devices on high speed train (HST) , or image capture devices such as digital cameras, sensors, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. The ‘terminal device’ can further has ‘multicast/broadcast’ feature, to support public safety and mission critical, V2X applications, transparent IPv4/IPv6 multicast delivery, IPTV, smart TV, radio services, software delivery over wireless, group communications and IoT applications. It may also be incorporated one or multiple Subscriber Identity Module (SIM) as known as Multi-SIM. The term “terminal device” can be used interchangeably with a UE, a mobile station, a subscriber station, a mobile terminal, a user terminal or a wireless device.

As used herein, the term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a satellite, a unmanned aerial systems (UAS) platform, a Node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a transmission reception point (TRP) , a remote radio unit (RRU) , a radio head (RH) , a remote radio head (RRH) , an IAB node, a low power node such as a femto node, a pico node, a reconfigurable intelligent surface (RIS) , and the like.

In one embodiment, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In one embodiment, the first network device may be a first RAT device and the second network device may be a second RAT device. In one embodiment, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device and the second network device. In one embodiment, first information may be transmitted to the terminal device from the first network device and second information may be transmitted to the terminal device from the second network device directly or via the first network device. In one embodiment, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

Communications discussed herein may conform to any suitable standards including, but not limited to, New Radio Access (NR) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , cdma2000, and Global System for Mobile Communications (GSM) and the like. Furthermore, the communications may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.85G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) , and the sixth (6G) communication protocols. The techniques described herein may be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies. The embodiments of the present disclosure may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or the sixth generation (6G) networks.

The terminal device or the network device may have Artificial intelligence (AI) or machine learning capability. It generally includes a model which has been trained from numerous collected data for a specific function, and can be used to predict some information.

The terminal device or the network device may work on several frequency ranges, e.g. FR1 (410 MHz –7125 MHz) , FR2 (24.25GHz to 71GHz) , frequency band larger than 100GHz as well as Tera Hertz (THz) . It can further work on licensed/unlicensed/shared spectrum. The terminal device may have more than one connection with the network device under Multi-Radio Dual Connectivity (MR-DC) application scenario. The terminal device or the network device can work on full duplex, flexible duplex and cross division duplex modes.

The embodiments of the present disclosure may be performed in test equipment, e.g., signal generator, signal analyzer, spectrum analyzer, network analyzer, test terminal device, test network device, or channel emulator.

The embodiments of the present disclosure may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or the sixth generation (6G) networks.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

As mentioned above, for a UE in RRC idle/inactive state, the periodic paging monitoring and measurement consume considerable power at UE side, which is critical for the power limited devices such as IoT devices or wearable devices.

A low power wake up signal (LP-WUS) is proposed in NR Release 18, which may study and evaluate techniques of low power signals and low power receivers, to enable extreme low power consumption and low wake up latency.

The LP-WUS is designed to be a simple signal so that the UE may consume extreme low power while detecting the LP-WUS. However, on the other hand, the LP-WUS may have a poor coverage, and the UE may not successfully detect the LP-WUS, that is, a miss detection of the LP-WUS may occurs. In this case, the UE may not wake up since an LP-WUS is miss detected, and the UE cannot receive the following signals, such as paging information, and the communication efficiency cannot be guaranteed. Therefore, some further studies are needed in case miss detection occurs during a wake up procedure.

Embodiments of the present disclosure provide a solution of communication. In the solution, two signals are used for indicating the terminal device whether to wake up. Specifically, the terminal device may determine whether a miss-detection of the second signal is happened based on the first signal, and thus a wrong determination on whether to wake up may be avoided. Principles and implementations of the present disclosure will be described in detail below with reference to the figures.

FIG. 1 illustrates an example communication system 100 in which some embodiments of the present disclosure can be implemented. The communication network 100 includes a network device 110 and a terminal device 120. The network device 110 can provide services to the terminal device 120.

In the system 100, it is assumed that the terminal device 120 is located within coverage of the network device 110. In some examples, a link from the network device 110 to the terminal device 120 is referred to as a downlink (DL) , while a link from the terminal device 120 to the network device 110 is referred to as an uplink (UL) . In downlink, the network device 110 is a transmitting (TX) device (or a transmitter) and the terminal device 120 is a receiving (RX) device (or a receiver) . In uplink, the terminal device 120 is a transmitting TX device (or a transmitter) and the network device 110 is a RX device (or a receiver) . In some embodiments, the network device 110 and the terminal device 120 may communicate with direct links/channels. DL may comprise one or more logical channels, including but not limited to a Physical Downlink Control Channel (PDCCH) and a Physical Downlink Shared Channel (PDSCH) . UL may comprise one or more logical channels, including but not limited to a Physical Uplink Control Channel (PUCCH) and a Physical Uplink Shared Channel (PUSCH) . As used herein, the term “channel” may refer to a carrier or a part of a carrier consisting of a contiguous set of resource blocks (RBs) on which a channel access procedure is performed in shared spectrum.

In some embodiments, the terminal device 120 may be in a main mode. In the context of the present disclose, the terms “main radio” , “main receiver” can be used interchangeably. The terminal device 120 may receive/transmit normal DL/UL transmission (e.g., PDSCH, PDCCH, PUSCH, PUCCH, etc. ) in the main mode with the main radio.

In some embodiments, the terminal device 120 may be in an idle/inactive mode. For example, the same coverage as the normal DL/UL transmission cannot be provided and the terminal device 120 may receive wake up signals (WUS) with wake up receivers (WUR) .

In some embodiments, the primary target for the WUS or WUR may be power-sensitive, small form-factor devices including IoT use cases (such as industrial sensors, controllers) and wearables. In some examples, low power wake up receiver architectures may be studied and evaluated. In some examples, wake up signal designs to support wake up receivers may be studied and evaluated. In some examples, L1 procedures and higher layer protocol changes needed to support the wake up signals may be studied and evaluated. In some examples, it is proposed to study potential UE power saving gains compared to the existing power saving mechanisms and their coverage availability, as well as latency impact. For example, system impact, such as network power consumption, coexistence with non-low-power-WUR UEs, network coverage/capacity/resource overhead may be included.

In some embodiments, the terminal device 120 may be in a low power mode. In the context of the present disclose, the terms “low power mode” , “LP mode” , “ultra-low power mode” can be used interchangeably, and the terms “low power radio” , “ultra-low power radio” , “low power receiver” , “ultra-low power receiver” , “wake-up receiver” can be used interchangeably.

In the present disclosure, the term “low power (LP) mode” may refer to a mode that the terminal device 120 is not required to perform at least one of: paging monitoring, cell selection and re-selection, measurement based on a synchronization signal block (SSB) or channel state information -reference signal (CSI-RS) , PDCCH monitoring, UL transmission, etc., and the terminal device 120 is required to perform LP signal monitoring and/or detection.

In the present disclosure, the term “low power (LP) radio” may refer to a radio used in the low power mode for transmission/reception. In an embodiment, the LP radio may be independent to the main radio, and it is not used for transmission/reception of the normal DL/UL transmissions. In another embodiment, the LP radio may share at least a part of the components of the main radio, and it may have lower power consumption than the main radio.

In some embodiments, the terminal device 120 may perform, when in a main mode, at least one of: paging monitoring, cell selection and re-selection, measurement based on SSB or CSI-RS, PDCCH monitoring, or UL transmission.

In some embodiments, the terminal device 120 may enter the LP mode by switching off the main radio. For example, the terminal device 120 is allowed to switch off its main radio and switch on its LP radio, wherein the LP radio is used to receive the LP signals and the main radio is used to receive or transmit the signals other than the LP signals.

Communications in the system 100, between the network device 110 and the terminal device 120 for example, may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) and the fifth generation (5G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Divided Multiple Address (CDMA) , Frequency Divided Multiple Address (FDMA) , Time Divided Multiple Address (TDMA) , Frequency Divided Duplexer (FDD) , Time Divided Duplexer (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Divided Multiple Access (OFDMA) and/or any other technologies currently known or to be developed in the future.

Embodiments of the present disclosure can be applied to any suitable scenarios. For example, embodiments of the present disclosure can be implemented at reduced capability NR devices. Alternatively, embodiments of the present disclosure can be implemented in one of the followings: NR multiple-input and multiple-output (MIMO) , NR sidelink enhancements, NR systems with frequency above 52.6GHz, an extending NR operation up to 71GHz, narrow band-Internet of Thing (NB-IOT) /enhanced Machine Type Communication (eMTC) over non-terrestrial networks (NTN) , NTN, UE power saving enhancements, NR coverage enhancement, NB-IoT and LTE-MTC, Integrated Access and Backhaul (IAB) , NR Multicast and Broadcast Services, or enhancements on Multi-Radio Dual-Connectivity.

It is to be understood that the numbers of devices (i.e., the network device 110 and the terminal device 120) and their connection relationships and types shown in FIG. 1 are only for the purpose of illustration without suggesting any limitation. The system 100 may include any suitable numbers of devices adapted for implementing embodiments of the present disclosure.

In some example embodiments, the terminal device 120, when in a low power mode, may receive a low power signal, such as an LP-WUS. In some embodiments, the LP-WUS may be used for indicating the terminal device 120 to wake up from the LP mode, and start to monitor a paging occasion for paging information, and the LP-WUS may be UE group specific (or UE specific) and may be an on-demand signal.

In some embodiments, the LP-WUS may be based on at least one amplitude modulation sequence, where the sequence may include a symbol with higher amplitude and a symbol with lower amplitude. In some examples, the amplitude modulation may include amplitude shift keying (ASK) or on-off keying (OOK) modulation. Specifically, on-off keying (OOK) modulation is widely considered due to its very simple receiver architecture and ultra-low power consumption. With OOK modulation, the receiver may detect the envelop or energy of the time domain signal with a relatively low sampling rate, and without complicated baseband processing. As an example, the OOK modulation is considered in the following disclosure as one of the amplitude modulation. An OOK modulation sequence may include at least one OOK on-symbol and at least one OOK off-symbol. The present disclosure does not limit this aspect. In some other embodiments, the LP-WUS may be based on at least one Gold sequence.

In some embodiments, the LP-WUS may occupy a set of time/frequency resources for a serving cell. FIG. 2A illustrates a schematic diagram of resources 210 occupied by an LP-WUS which can be used in some example embodiments of the present disclosure. In frequency domain, the resources allocated to the LP-WUS 212 may be overlapped with a set of PRBs or subcarriers, i.e., the terminal device 120 may be indicated a set of PRBs or subcarriers, and the frequency resources of the set of PRBs or subcarriers are used by the LP-WUS 212. In time domain, the resources allocated to the LP-WUS 212 may be overlapped with a set of OFDM symbols, i.e., the terminal device 120 may be indicated a set of OFDM symbols, and the time resources of the set of OFDM symbols are used by the LP-WUS 212.

In some examples, OOK modulation is used to generate the LP-WUS, an OOK symbol can be an OOK on-symbol (denoted by logical “1” ) or an OOK off-symbol (denoted by logical “0” ) , where the OOK on-symbol has a relatively high power, and the OOK off-symbol has zero power or relatively low power.

It is to be understood that the OOK symbol may be equal to or may be not equal to an OFDM symbol. FIGS. 2B-2C illustrate schematic diagrams of OOK symbols which can be used in some example embodiments of the present disclosure.

As shown in FIG. 2B, an OOK on-symbol or an OOK off-symbol may have a duration which equals to the duration of an OFDM symbol. In this case, an OOK on-symbol and an OOK off-symbol are realized by a non-zero power OFDM symbol and a zero power OFDM symbol respectively.

As shown in FIG. 2C, an OOK on-symbol or an OOK off-symbol may have a duration which is shorter than an OFDM symbol. In this case, the OOK on-symbol and OOK off-symbol can be realized by DFT-s-OFDM, or by independent time domain generation.

In some embodiments, an LP-WUS may include a sequence of OOK symbols which is formed by at least one OOK on-symbol and at least one OOK off-symbol, e.g., “1010…1” as shown in FIGS. 2B-2C.

Please note that, in the present disclosure, if not specified otherwise, the term “OFDM symbol” indicates CP-OFDM symbol, or any variant of OFDM symbol, e.g., GI-OFDM, zero CP OFDM, unique word OFDM, etc.

In some embodiments, the OOK on-symbol has a higher power, and the OOK off-symbol has a lower power. In the context of the present disclose, the terms “power” , “energy” , “amplitude” , “strength” may be used interchangeably.

Reference is further made to FIG. 3, which illustrates a signalling chart illustrating communication process 300 in accordance with some example embodiments of the present disclosure. Only for the purpose of discussion, the process 300 will be described with reference to FIG. 1. The process 300 may involve the network device 110 and the terminal device 120.

The network device 110 generates 310 a first signal for multiple terminal devices including the terminal device 120, where the multiple terminal devices may be in a low power mode. The network device 110 generates 320 a second signal for the terminal device 120 if the terminal device 120 is needed to wake up, where the second signal is at least a part of a low power wake up signal. In some embodiments, the network device 110 may determine whether one of the multiple terminal devices (such as the terminal device 120) is needed to wake up.

The first signal is different from the second signal. In some embodiments, the first signal and the second signal may be two different low power wake up signals. In some embodiments, the first signal and the second signal may be two different parts of a low power wake up signal. In some embodiments, the second signal may be a low power wake up signal and the first signal is another signal such as a synchronization signal.

In some embodiments, the network device 110 may always generate the first signal regardless of the second signal. In some embodiments, the network device 110 may generate the first signal only if there needs to generate the second signal. For example, the network device 110 may determine whether one of the multiple terminal devices is needed to wake up, and the network device 110 may generate the first signal and the second signal if at least one of the multiple terminal devices is needed to wake up. In some embodiments, the second signal is an on-demand signal.

In some example embodiments, the first signal may comprise a first sequence. For example, the first sequence may be an amplitude modulation sequence, such as an OOK sequence, which include at least one OOK on-symbol and at least one OOK off-symbol. In some example embodiments, the second signal may comprise a second sequence. For example, the second sequence may be an amplitude modulation sequence, such as an OOK sequence, which include at least one OOK on-symbol and at least one OOK off-symbol.

In some embodiments, the first sequence may be generated based on a first ID, denoted as N _ID1. In some embodiments, the second sequence may be generated based on a second ID, denoted as N _ID2. The first sequence is different from the second sequence, and the first ID is different from the second ID.

In some examples, the first ID is generated based on one or more of: a cell ID, a cell group ID, a public land mobile network (PLMN) ID, a position of the paging occasion, a tracking area code (TAC) , a tracking area ID, or an ID configured by the network device. For example, the ID configured by the network device may be a UE group ID which is different from the second ID. For example, the first ID may be generated based on a cell ID (denoted as C _ID) , represented by N _ID1 = C _ID mod A, where A is an integer, e.g., A = 3, 6, 9, or 15.

In some examples, the first sequence with the first ID may be generated based on one or more m-sequences. For example, m-sequence may be represented as x (m) , the first sequence may be represented as d _s1 (n) , and the first sequence may be defined as:

d _s1 (n) =1-2x (m) , m= (n+a ₁N _ID1) mod a ₂ (1)

with 0≤n<a ₂.

In the above equation, a ₁ and a ₂ may be fixed values. As an example, if a ₂=31, it may define that

x (i+5) = (x (i+2) +x (i) ) mod 2, (2)

[x (4) x (3) x (2) x (1) x (0) ] = [b ₄ b ₃ b ₂ b ₁ b ₀] . (3)

As another example, if a ₂=63, it may define that

x (i+6) = (x (i+3) +x (i) ) mod 2 (4)

[x (5) x (4) x (3) x (2) x (1) x (0) ] = [b ₅ b ₄ b ₃ b ₂ b ₁ b ₀] . (5)

In the above equations, a ₁ and a ₂ are two integers, and a ₂ may be equal to the length of the sequence. Each of b ₅, b ₄, b ₃, b ₂, b ₁, b ₀ may be 0 or 1. N _ID1 may be an integer which is associated with an identifier, and the identifier may be a cell ID, a cell group ID, a PLMN, a position of the paging occasion, a tracking area ID, a tracking area code (TAC) , or an integer indicated by the network device 110, as discussed above.

In some other examples, the first sequence may be generated based on a first bit sequence with an encoding operation. The first bit sequence may be generated based on the first ID, for example, the first bit sequence may be a binary format of the first ID or may be a bitmap based on the first ID. The first bit sequence may be encoded to a code block which may be further mapped to the first sequence.

In some examples, the second ID is generated based on one or more of: a UE ID, a UE group ID, a paging probability, or an ID configured by the network device. For example, the ID configured by the network device may be a group ID which is different from the first ID.

In some examples, the second sequence with the second ID may be generated based on at least one m-sequence. For example, m-sequence may be represented as x (m) , the second sequence may be represented as d _s2 (n) , and the second sequence may be defined as:

d _s2 (n) = [1-2x ₁ (m ₁) ] [1-2x ₂ (m ₂) ] , (6)

or d _s2 (n) = [x ₁ (m ₁) +x ₂ (m ₂) ] mod 2 (7)

In the above equations (6) and (7) , x ₁ (m ₁) and x ₂ (m ₂) are two m-sequences with similar designs as the m-sequence stated in equation (1) .

In some examples, at least m ₁ or m ₂ is determined based on the second ID, that is, m ₁ and/or m ₂ is associated with the second ID. For example, m ₁ is associated with the first ID and the second ID, and m ₂ is associated with the first ID. For example,

m ₂= (n+N _ID1mod a4) mod C (9)

where floor () is a function that outputs the largest integer less than or equal to the input, a1, a2, a3, a4, B and C are integers.

In some other examples, the second sequence may be generated based on a second bit sequence with an encoding operation. The second bit sequence may be generated based on the second ID, for example, the second bit sequence may be a binary format of the second ID or may be a bitmap based on the second ID. The second bit sequence may be encoded to a code block which may be further mapped to the second sequence.

As such, the first sequence may be cell-specific, i.e., common for all UE groups. Thus, the first sequence may be shared among all UEs in the cell and accordingly the overhead may be saved.

As such, the second sequence may be UE group-specific, thus it is beneficial for UE power saving because it avoids the terminal device frequently wake up with no effective paging information.

In some example embodiments, the second signal may be one of multiple signals corresponding to multiple behaviors. The multiple behaviors may be those the terminal device 120 may perform while waking up from the low power mode. In some examples, the multiple signals may be used for indicating multiple behaviors, and the second signal may be used for indicating one of the multiple behaviors. In some embodiments, the multiple behaviors may include: switching on a main radio, switching off a low power radio, stopping monitoring the second signal, monitoring at least one paging occasion, performing a measurement, updating a configuration of the second signal, performing an initial access procedure, and performing a cell reselection procedure.

In some example embodiments, the second signal may be associated with the first signal. In some embodiments, multiple terminal devices may be divided in to multiple groups, and the network device 110 may determine multiple candidate signals for the multiple groups, for example, different candidate signals may be generated based on different group IDs.

In some embodiments, the second signal may be one of the multiple candidate signals. For example, the terminal device 120 may belong to one group of the multiple groups, and the second signal may be the candidate signal which corresponds to the one group.

Continuing with reference to FIG. 3, the network device 110 transmits 330 the first signal 332. In some examples, the first signal is transmitted to multiple terminal devices which include the terminal device 120.

The network device 110 transmits 340 the second signal 334 to the terminal device 120. In some examples, if the network device 110 determines to wake up the terminal device 120, the second signal can be transmitted.

In some example embodiments, the first signal and the second signal occupy different time resources. In some embodiments, the time resource occupied by the first signal may be an occasion for the first signal, or may be referred to as a first occasion. In some embodiments, the time resource occupied by the second signal may be an occasion for the second signal, or may be referred to as a second occasion.

It is understood that the occasion discussed here may refer to a transmission occasion for the network device 110 and may refer to a monitoring occasion for the terminal device 120.

In some embodiments, the first occasion and the second occasion may be associated with a paging occasion (PO) . As an example, both the first occasion and the second occasion are located within a time duration (denoted as T) before the associated paging occasion. In some examples, the time interval between the time duration (such as the ending time point of the time duration) and the paging occasion (such as the starting time point of the paging occasion) is greater than a predefined gap. Detailed description may refer to FIG. 5A.

As another example, the first occasion is located within a first time duration (denoted as T1) before the associated paging occasion, and the second occasion is located within a second time duration (denoted as T2) before the associated paging occasion. In some examples, the time interval between the first time duration (such as the ending time point of the first time duration) and the paging occasion (such as the starting time point of the paging occasion) is greater than a predefined gap, and the time interval between the second time duration (such as the ending time point of the second time duration) and the paging occasion (such as the starting time point of the paging occasion) is greater than the predefined gap. Detailed description may refer to FIG. 5B.

For example, the predefined gap may be called as a transition gap and it may equal to multiple OFDM symbols or multiple milliseconds.

In some other embodiments, the first occasion and the second occasion may be not associated with a particular paging occasion. In this case, the terminal device 120 may monitor paging occasions after waking up, for example until detects any paging information. In some examples, the terminal device 120 may monitor paging occasions after a predefined gap.

In some example embodiments, an occasion for the first signal may be associated with an occasion for the second signal. In some other example embodiments, an occasion for the first signal may be associated with multiple occasions for the second signals.

In some example embodiments, the second signal may be transmitted after the end of the first signal. In some embodiments, the second signal and the first signal may be continuous in the time domain. For example, the second signal may be transmitted immediately after the first signal. For example, the first signal and the second signal may be two sub-signals of a low power wake up signal. For example, the first signal includes a first sequence, the second signal includes a second sequence, and the first sequence and the second sequence may be considered to be two sub-sequences of a long sequence.

In some other embodiments, the second signal and the first signal may not be continuous in the time domain. For example, there is a gap between the end of the first signal and the start of the second signal. In other words, there is a gap between the occasion for the first signal and the occasion for the second signal.

In some examples, the gap may be known to the terminal device 120, for example, the gap may be a fixed value or may be preconfigured by the network device 110. In some other examples, the gap is unknown to the terminal device 120, in this case, the terminal device 120 may blind detect the second signal after the first signal is detected.

In some example embodiments, the first signal and the second signal may be configured independently. In some examples, there may be no explicit time domain relation between the occasion for the first signal and the occasion for the second signal. In this case, the terminal device 120 may monitor the first signal and the second signal simultaneously. For example, the terminal device 120 may use two parallel detectors to monitor the first signal and the second signal respectively. In some examples, the detector may be an energy detector or an envelope detector.

Continuing with reference to FIG. 3, the terminal device 120 monitors 322 the first signal. And the terminal device 120 monitors 324 the second signal.

In some example embodiments, the terminal device 120 may monitor the first signal and the second signal in parallel. For example, the terminal device 120 may use two different detectors to monitor the first signal and the second signal respectively.

In some other example embodiments, the terminal device 120 may monitor the first signal, and may determine that the first signal is detected. For example, the terminal device 120 may receive 334 the first signal 332. In some examples, the terminal device 120 may start monitoring the second signal after the first signal is detected.

In some embodiments, the terminal device 120 may determine whether the first signal is detected. In some examples, the terminal device 120 may determine that the first signal is detected based on one or more of: an output of a detector of the first signal being greater or not less than a first threshold, a measurement result of the first signal being greater or not less than a second threshold, a number of successfully received first signals during a duration being greater or not less than a first threshold number, or a number of failed received first signals during the duration being less or not greater than a second threshold number. In some examples, any of the thresholds, such as the first threshold, the second threshold, the first threshold number or the second threshold number, is predefined or is preconfigured by the network device 110 or is determined by the terminal device 120 based on its implementation, the present disclosure does not limit this aspect. For example, the measurement result may include one or more of: received signal strength, a received signal power, or a signal to interference plus noise ratio (SINR) .

For a specific example, if the first signal is successfully detected for at least N11 times during a specific time duration, the terminal device 120 may determine that the first signal is detected. For another specific example, if the times of miss-detection of the first signal is less than N12 during a specific time duration, the terminal device 120 may determine that the first signal is detected. For another specific example, if a first signal is successfully detected in the most recent occasion before a paging occasion, the terminal device 120 may determine that the first signal is detected. For another specific example, if the first signal is successfully detected in at least N21 occasions among the most recent N22 occasions before the paging occasion, the terminal device 120 may determine that the first signal is detected. It is understood that N11, N12, N21 and N22 are integers. It should be understood that although some examples are listed here, some other examples may be applied and the present disclosure does not limit this aspect.

In some embodiments, the terminal device 120 may determine whether the second signal is detected. In some examples, the terminal device 120 may determine that the second signal is detected based on one or more of: an output of a detector of the second signal being greater or not less than a third threshold, a measurement result of the second signal being greater or not less than a fourth threshold, a number of successfully received second signals during a duration being greater or not less than a third threshold number, or a number of failed received second signals during the duration being less or not greater than a fourth threshold number. In some examples, any of the thresholds, such as the third threshold, the fourth threshold, the third threshold number or the fourth threshold number, is predefined or is preconfigured by the network device 110 or is determined by the terminal device 120 based on its implementation, the present disclosure does not limit this aspect. In some examples, the third threshold may equal to the first threshold, the fourth threshold may equal to the second threshold, the third threshold number may equal to the first threshold number, and the fourth threshold number may equal to the second threshold number. For example, the measurement result may include one or more of: received signal strength, a received signal power, or a signal to interference plus noise ratio (SINR) . In some embodiments, the successfully detection of the second signal is similar with that of the first signal, and thus the present disclose does not describe in detail

In some other embodiments, the first signal may include a first sequence and the first sequence may be generated based on a first bit sequence with an encoding operation. In some examples, the terminal device 120 may obtain a first decoded bit sequence of a first received signal, and determine whether the first decoded bit sequence is the same as the first bit sequence. The terminal device 120 may determine that the first signal is successfully detected if the first decoded bit sequence is the same as the first bit sequence.

In some other embodiments, the second signal may include a second sequence and the second sequence may be generated based on a second bit sequence with an encoding operation. In some examples, the terminal device 120 may obtain a second decoded bit sequence of a second received signal, and determine whether the second decoded bit sequence is the same as the second bit sequence. The terminal device 120 may determine that the second signal is successfully detected if the second decoded bit sequence is the same as the second bit sequence.

In some examples, the time domain relation of the first signal and the second signal is known to the terminal device 120. In this case, the terminal device 120 may determine the occasion for the second signal based on the occasion for the detected first signal, and the terminal device 120 may monitor the second signal in the occasion for the second signal. For example, the second signal and the first signal are continuous at the time domain. For another example, there is a gap between the end of the first signal and the start of the second signal, where the gap is known to the terminal device 120.

In some examples, the time domain relation of the first signal and the second signal is unknown to the terminal device 120. For example, there is a gap between the end of the first signal and the start of the second signal, where the gap is unknown to the terminal device 120. In this case, the terminal device 120 may blind detect the second signal after the first signal is detected.

In some example embodiments, the terminal device 120 may determine the further behavior based on the monitoring results.

In some example embodiments, as shown at 350, if the first signal is detected and the second signal is detected, the terminal device 120 may wake up from the low power mode. For example, the terminal device 120 may receive 334 the first signal and receive 344 the second signal 342.

In some example embodiments, as shown at 360, if the first signal is detected and the second signal is not detected, the terminal device 120 may stay in the low power mode, that is, not wake up from the low power mode. For example, the terminal device 120 may receive 334 the first signal, but not receive a second signal.

The first signal may be used to determine whether a miss-detection of the second signal is occurred. If the first signal is detected, it implies that the channel quality is good and the terminal device 120 may determine that there is no miss-detection of the second signal. In this case, if the second signal is not detected, the terminal device 120 may determine that the second signal is not transmitted by the network device 110, and thus the terminal device 120 will not wake up.

Alternatively of additionally, if the first signal is not detected and the second signal is detected, the terminal device 120 may wake up from the low power mode, and may further perform one or more of: starting a measurement on the first signal, starting a reselection of the second signal, transmitting a miss detection report of the first signal to the network device, or transmitting a measurement result report of the first signal to the network device.

Since the first signal is not detected and the second signal is detected, the terminal device 120 may determine a miss-detection of the first signal is occurred. In this case, the terminal device 120 may determine the channel condition is not good enough. Thus, the terminal device 120 may perform one or more of additional operations after waking up.

Alternatively of additionally, if the first signal is not detected and the second signal is not detected, the terminal device 120 may wake up from the low power mode or the terminal device 120 may stay in the low power mode (i.e., not wake up) .

In some example embodiments, if the first signal is not detected and the second signal is not detected, the terminal device 120 may determine configuration information from the network device 110. If the configuration information indicates a first value, the terminal device 120 may determine to wake up from the low power mode. If the configuration information indicates a second value or if the configuration information is absent (i.e., not configured by the network device 110) , the terminal device 120 may determine to stay in the low power mode (i.e., not wake up) .

In some examples, the network device 110 may transmit configuration information to the terminal device 120, where the configuration information may indicate a first value or a second value. In some examples, the first signal if not transmitted is no second signal is needed to transmit. In this case, the network device 110 may configure that the configuration information indicated the second value.

In some examples, the configuration information may be carried in an RRC message, for example, the configuration information may be carried in a field of an RRC information element (IE) . In some examples, the configuration information may be called as high layer information. In some examples, the configuration information may be carried in a medium access control (MAC) control element (CE) , such as in a field of a MAC CE.

In some examples, the configuration information may be absent. For example, the network device 110 does not transmit any configuration information to the terminal device 120. In this case, the terminal device 120 may determine that the configuration information is absent, and may stay in the low power mode if the first signal is not detected and the second signal is not detected either.

In some example embodiments, the term “wake up” in the present disclosure may mean at least one of the following behaviors: switching on a main radio, switching off a low power radio, stopping monitoring the second signal, monitoring at least one paging occasion, performing a measurement, updating a configuration of the second signal, performing an initial access procedure, or performing a cell reselection procedure.

For example, the terminal device 120 may switch off the low power radio and switch on the main radio. For example, the terminal device 120 may stop monitor the first signal and the second signal and start monitoring a paging occasion. For example, the terminal device 120 may change the current configuration of the second signal, for example, multiple different configurations of the second signal may be pre-stored at the terminal device 120, and the terminal device 120 may choose another configuration different from the current configuration to update the configuration of the second signal. For example, the terminal device 120 may use another configuration to perform a low power wake up signal reselection. It should be understood that although some examples are listed here, some other examples may be applied and the present disclosure does not limit this aspect.

In some example embodiments, the detected second signal may be one of multiple signals, and the multiple signals are corresponding to multiple behaviors. In some embodiments, the terminal device 120 may be configured to monitor at most one signal from the multiple signals. In this case, the terminal device 120 may determine the behavior corresponding to the second signal and may further perform the determined behavior. In some other embodiments, the terminal device 120 may be configured to monitor one or more signals from the multiple signals. In this case, one or more signals in the multiple signals may be detected, and the terminal device 120 may perform one or more behaviors corresponding to the one or more signals.

As such, two signals may be used for indicating the terminal device 120 whether to wake up. For example, the first signal may be used for the terminal device 120 to determine whether the second signal is miss-detected. For example, the second signal may be used for the terminal device 120 to determine whether the terminal device 120 should wake up or not.

In some cases, the network device 110 may always transmit the first signal for a specific paging occasion, but only transmit the second signal if the terminal device associated with the second signal is intended to be paged. For example, the network device 110 may transmit (1+M) signals for a paging occasion, where the 1 signal refers to the first signals and the M signals refers to M second signals. M is an integer and may equal to the number of groups in which the network device 110 intends to wake up the terminal devices. It is understood that if no terminal device is intended to wake up, M =0. Therefore, the overhead may be reduced.

Since the first signal is always transmitted by the network device 110, the terminal device 120 may determine whether a miss-detection of the second signal is happened based on the first signal, and thus a wrong determination on whether to wake up may be avoided.

As discussed above, the first signal may be cell-specific, thus the first signal may be shared among all terminal devices in the cell of the network device 110. Thus, the overhead may be saved. The terminal device 120 may assume that the first signal is always transmitted by the network device 110 before a paging occasion, and may further assume that the second signal is only transmitted if the terminal device 120 belongs to a group including a terminal device intended to be woke up. Since the second signal is UE group-specific, there is no need for the terminal device 120 to wake up frequently with no effective paging information, and thus the power consumption at the terminal device 120 may be saved.

Reference is further made to FIG. 4A, which illustrates a schematic diagram 410 of the time resources of the first signal and the second signal according to some embodiments of the present disclosure. As shown in FIG . 4A, an occasion for the second signal 402-1 is immediately following an occasion for the first signal 401-1, an occasion for the second signal 402-2 is immediately following an occasion for the first signal 401-2.

In some examples, the first signal and the second signal are contiguous at the time domain. In some examples, the terminal device 120 may start monitoring the second signal upon the first signal is successfully detected.

In some embodiments, if the terminal device 120 successfully detects the first signal at the occasion 401-1 and successfully detects the second signal at the occasion 402-1, the terminal device 120 may wake up, for example, the terminal device 120 may monitor the paging occasion 403.

In some examples, the first signal and the second signal may be combined as a low power wake up signal (LP-WUS) . For example, the first signal is a part of the LP-WUS, and the second signal is another part of the LP-WUS. For example, the LP-WUS includes a sequence, the first signal includes a sub-sequence of the sequence, and the second signal includes another sub-sequence of the sequence.

FIG. 4B illustrates a schematic diagram 420 of the time resources of the first signal and the second signal according to some embodiments of the present disclosure. As shown in FIG . 4B, an occasion for the second signal 402-1 is after an occasion for the first signal 401-1 and there is gap there between, an occasion for the second signal 402-2 is after an occasion for the first signal 401-2 and there is gap there between.

In some examples, the gap may be a predefined fixed value or the gap may be pre-configured by the network device 110. In some examples, the gap is known to the terminal device 120, and the terminal device 120 may monitor the second signal after the gap upon the first signal is successfully detected.

In some examples, the gap is unknown to the terminal device 120, and the terminal device 120 may blind detect the second signal after the first signal is successfully detected.

In some examples, the first signal and the second signal may be two associated low power wake up signals.

As shown in FIG. 4A or FIG. 4B, an occasion for the second signal may be associated with an occasion for the first signal.

FIG. 4C illustrates a schematic diagram 430 of the time resources of the first signal and the second signal according to some embodiments of the present disclosure. In some examples, an occasion for the first signal may be associated with multiple occasions for the second signal.

As shown in FIG . 4C, multiples occasions 402-1 to 402-3 for the second signal is associated with an occasion 401-1 for the first signal.

FIG. 5A illustrates some example schematic diagram 510 of time durations of the first signal and the second signal according to some embodiments of the present disclosure. The occasion for the first signal (401-1, 401-2) and the occasion for the second signal (402-1, 402-2) are within the time duration T, and the time interval between the time duration T (such as the ending time point of the time duration T) and the paging occasion 403 (such as the starting time point of the paging occasion 403) is greater than (or not less than) a predefined gap Δ.

FIG. 5B illustrates some example schematic diagram 520 of time durations of the first signal and the second signal according to some embodiments of the present disclosure. The occasion for the first signal (401-1, 401-2) is within a first time duration T1, and the occasion for the second signal (402-1, 402-2) is within a second time duration T2. The time interval between the first time duration T1 (such as the ending time point of the time duration T1) and the paging occasion 403 (such as the starting time point of the paging occasion 403) is greater than (or not less than) a predefined gap Δ, and the time interval between the second time duration T2 (such as the ending time point of the time duration T2) and the paging occasion 403 (such as the starting time point of the paging occasion 403) is greater than (or not less than) a predefined gap Δ.

In some embodiments, the first signal may be a synchronization signal, such as a low power synchronization signal.

FIG. 6 illustrates a schematic diagram 600 of multiple candidate signals including the second signal according to some embodiments of the present disclosure. In some embodiments, the network device 110 may configure multiple candidate signals for the second signal. In some examples, the multiple candidate signals may be associated with the first signal. In some examples, the multiple candidate signals may be associated with a paging occasion. In some examples, the multiple candidate signals may be generated based on different group IDs.

As shown in FIG. 6, there may be four occasions 621 to 624 for four candidate signals which are associated with the paging occasion 403. The four occasions 621 to 624 for four candidate signals may be associated with the first signal. In some examples, the multiple occasions for the multiple candidate signals may be within a time duration before the associated paging occasion. As shown in FIG. 6, the time duration is denoted as T.

In some embodiments, the network device 110 may transmit the first signal, and transmit the second signal which is from the multiple candidate signals. For example, the network device 110 may transmit the first signal and at least one candidate signal.

In some embodiments, the network device 110 may transmit the first signal, without transmitting the second signal, i.e., without transmitting any of the multiple candidate signals.

In some embodiments, the network device 110 may not transmit either the first signal or any of the multiple candidate signals. For example, the configuration information may indicate a second value or the configuration information is absent. As such, the terminal device 120 may stay in the low power mode if either the first signal or the second signal is detected.

Reference is further made to FIG. 7, which illustrates a schematic diagram 700 of multiple occasions for a wake up signal according to some embodiments of the present disclosure.

The network device 110 may configure a low power wake up signal for waking up from a low power mode. In some embodiments, the low power wake up signal may include at least one sequence, such as m-sequence.

In some example embodiments, the network device 110 may configure multiple occasions for the low power wake up signal, and the multiple occasions are associated with a paging occasion.

As shown in FIG. 7, there are four occasions 720-1 to 720-4 for the low power wake up signal, which are associated with the paging occasion 730.

In some example embodiments, the network device 110 may transmit the low power wake up signal at each of the multiple occasions. In other words, the network device 110 may transmit the signal repeatedly at the multiple occasions. In some examples, the terminal device 120 may monitor the low power wake up signal at each of the multiple occasions. In some examples, the terminal device 120 may determine whether the low power wake up signal is detected by combining the received signals at the multiple occasions. In some examples, the terminal device 120 may wake up from the low power mode if the low power wake up signal is detected based on the combination of the received signals. In some examples, the terminal device 120 may determine to not wake up from the low power mode (i.e., stay in the low power mode) if the low power wake up signal is not detected based on the combination of the received signals.

In some other example embodiments, the network device 110 may transmit the low power wake up signal at least one of the multiple occasions. For example, the network device 110 may transmit the low power wake up signal at a subset of the multiple occasions. In some examples, the network device 110 may determine the subset, such as based on the network implementation.

In some examples, the terminal device 120 may monitor the low power wake up signal at each of the multiple occasions individually. For example, the terminal device 120 may monitor all the occasions until the low power wake up signal is successfully detected at one of the multiple occasions. For example, the terminal device 120 may monitor all the occasions until the last occasion is passed and the low power wake up signal is not detected. In some examples, the terminal device 120 may wake up from the low power mode if the low power wake up signal is detected at one of the multiple occasions. In some examples, the terminal device 120 may determine to not wake up from the low power mode (i.e., stay in the low power mode) if the low power wake up signal is not detected at each of the multiple occasions.

As such, multiple occasions for the low power wake up signal may be configured, and the terminal device may monitor the multiple occasions to detect the low power wake up signal. Thus, a probability of miss detection may be reduced, and the communication efficiency may be enhanced.

FIG. 8 illustrates a flowchart of an example method 800 implemented at a terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 800 will be described from the perspective of the terminal device 120 with reference to FIG. 1.

At block 810, the terminal device 120 in a low power mode monitors a first signal from the network device 110. At block 820, the terminal device 120 monitors a second signal from the network device 110, the second signal is at least a part of a low power wake up signal. At block 830, if the first signal is detected and the second signal is detected, the terminal device 120 wakes up from the low power mode. At block 840, if the first signal is detected and the second signal is not detected, the terminal device 120 stays in the low power mode.

In some example embodiments, if the first signal is not detected and the second signal is detected, the terminal device 120 wakes up from the low power mode; and performs one or more of: starting a measurement on the first signal, starting a reselection of the second signal, transmitting a miss detection report of the first signal to the network device, or transmitting a measurement result report of the first signal to the network device.

In some example embodiments, if the first signal is detected, the terminal device 120 monitors the second signal.

In some example embodiments, if the first signal is not detected and the second signal is not detected, the terminal device 120 determines configuration information from the network device 110. If the configuration information indicates a first value, the terminal device 120 wakes up from the low power mode. If the configuration information is absent or the configuration information indicates a second value, the terminal device 120 stays in the low power mode.

In some example embodiments, the terminal device 120 determines that the first signal is detected based on one or more of: an output of a detector of the first signal being greater or not less than a first threshold, a measurement result of the first signal being greater or not less than a second threshold, a number of successfully received first signals during a duration being greater or not less than a first threshold number, or a number of failed received first signals during the duration being less or not greater than a second threshold number.

In some example embodiments, the measurement result comprises at least one of: received signal strength, received signal power, or signal to interference plus noise ratio (SINR) .

In some example embodiments, an occasion for the first signal and/or an occasion for the second signal is associated with a paging occasion.

In some example embodiments, the occasion for the first signal is located within a first time period before the paging occasion. In some example embodiments, the occasion for the second signal is located within a second time period before the paging occasion.

In some example embodiments, a time interval between the occasion for the first signal and the paging occasion is greater than a predefined gap. In some example embodiments, a time interval between the occasion for the second signal and the paging occasion is greater than the predefined gap.

In some example embodiments, an occasion for the second signal and an occasion for the first signal are continuous at the time domain.

In some example embodiments, there is a gap between an occasion for the first signal and an occasion for the second signal.

In some example embodiments, the gap is a fixed value or is preconfigured by the network device.

In some example embodiments, the gap is unknown to the terminal device 120, and the terminal device 120 may blink monitor the second signal if the first signal is detected.

In some example embodiments, the terminal device 120 wakes up from the low power mode means the terminal device 120 performs at least one of a plurality of behaviors: switching on a main radio, switching off a low power radio, stopping monitoring the second signal, monitoring at least one paging occasion, performing a measurement, updating a configuration of the second signal, performing an initial access procedure, or performing a cell reselection procedure.

In some example embodiments, the second signal is one of a plurality of signals corresponding to the plurality of behaviors.

In some example embodiments, the first signal is associated with a first identifier (ID) being based on at least one of: an ID of a cell of the network device, an ID of a cell group of the network device, an ID of a public land mobile network of the network device, position information of a paging occasion following the first signal, a tracking area ID associated with the network device, a tracking area code associated with the network device, or an indication provided by the network device for indicating the first signal.

In some example embodiments, the second signal is associated with a second ID being based on at least one of: an ID of the terminal device, an ID of a group to which the terminal device belongs, a paging probability, or an indication provided by the network device for indicating the second signal.

In some example embodiments, the second signal is one of a plurality of candidate signals associated with the first signal.

In some example embodiments, the first signal is used for synchronization.

FIG. 9 illustrates a flowchart of an example method 900 implemented at a network device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 900 will be described from the perspective of the network device 110 with reference to FIG. 1.

At block 910, the network device 110 generates a first signal for a plurality of terminal devices in a low power mode. At block 920, the network device 110 determines whether to wake up one of the plurality of terminal devices. At block 930, the network device 110 generates a second signal for the one of the plurality of terminal devices if the one of the plurality of terminal devices is needed to wake up, where the second signal is a low power wake up signal. At block 940, the network device 110 transmits the first signal to the plurality of terminal devices. At block 950, the network device 110 transmits the second signal to the one of the plurality of terminal devices.

In some example embodiments, the network device 110 generates the first signal for the plurality of terminal devices if the one of the plurality of terminal devices is needed to wake up.

In some example embodiments, the network device 110 receives, from the one of the plurality of terminal devices, at least one of: a miss detection report of the first signal, or a measurement result report of the first signal.

In some example embodiments, the network device 110 transmits an indication of the gap to the one of the plurality of terminal devices.

In some example embodiments, the second signal is one of a plurality of signals corresponding to a plurality of behaviors, the plurality of behaviors comprise: switching on a main radio, switching off a low power radio, stopping monitoring the second signal, monitoring at least one paging occasion, performing a measurement, updating a configuration of the second signal, performing an initial access procedure, or performing a cell reselection.

In some example embodiments, the second signal is associated with a second ID being based on at least one of: an ID of the one of the plurality of terminal devices, an ID of a group to which the one of the plurality of terminal devices belongs, a paging probability, or an indication provided by the network device for indicating the second signal.

In some example embodiments, the first signal is used for synchronization.

Details of some embodiments according to the present disclosure have been described with reference to FIGS. 1-9. Now an example implementation of the terminal device and the network device will be discussed below.

In some example embodiments, a terminal device comprises circuitry configured to:monitor a first signal from a network device; monitor a second signal from the network device, the second signal is at least a part of a low power wake up signal; if the first signal is detected and the second signal is detected, wake up from the low power mode; or if the first signal is detected and the second signal is not detected, stay in the low power mode.

In some example embodiments, the terminal device comprises circuitry configured to:if the first signal is not detected and the second signal is detected, wake up from the low power mode; and performs one or more of: starting a measurement on the first signal, starting a reselection of the second signal, transmitting a miss detection report of the first signal to the network device, or transmitting a measurement result report of the first signal to the network device.

In some example embodiments, the terminal device comprises circuitry configured to:if the first signal is detected, monitor the second signal.

In some example embodiments, the terminal device comprises circuitry configured to: if the first signal is not detected and the second signal is not detected, determine configuration information from the network device 110; if the configuration information indicates a first value, wake up from the low power mode; and if the configuration information is absent or the configuration information indicates a second value, stay in the low power mode.

In some example embodiments, the terminal device comprises circuitry configured to: determine that the first signal is detected based on one or more of: an output of a detector of the first signal being greater or not less than a first threshold, a measurement result of the first signal being greater or not less than a second threshold, a number of successfully received first signals during a duration being greater or not less than a first threshold number, or a number of failed received first signals during the duration being less or not greater than a second threshold number.

In some example embodiments, the gap is unknown to the terminal device, and the terminal device comprises circuitry configured to: blink monitor the second signal if the first signal is detected.

In some example embodiments, the terminal device comprises circuitry configured to: wake up from the low power mode by performing at least one of a plurality of behaviors: switching on a main radio, switching off a low power radio, stopping monitoring the second signal, monitoring at least one paging occasion, performing a measurement, updating a configuration of the second signal, performing an initial access procedure, or performing a cell reselection procedure.

In some example embodiments, the first signal is used for synchronization.

In some example embodiments, a network device comprises circuitry configured to: generate a first signal for a plurality of terminal devices in a low power mode; determine whether to wake up one of the plurality of terminal devices; generate a second signal for the one of the plurality of terminal devices if the one of the plurality of terminal devices is needed to wake up, where the second signal is a low power wake up signal; transmit the first signal to the plurality of terminal devices; and transmit the second signal to the one of the plurality of terminal devices.

In some example embodiments, the network device comprises circuitry configured to: generate the first signal for the plurality of terminal devices if the one of the plurality of terminal devices is needed to wake up.

In some example embodiments, the network device comprises circuitry configured to: receive, from the one of the plurality of terminal devices, at least one of: a miss detection report of the first signal, or a measurement result report of the first signal.

In some example embodiments, the network device comprises circuitry configured to: transmit an indication of the gap to the one of the plurality of terminal devices.

In some example embodiments, the first signal is used for synchronization.

FIG. 10 illustrates a simplified block diagram of a device 1000 that is suitable for implementing embodiments of the present disclosure. The device 1000 can be considered as a further example implementation of the terminal device 120, and the network device 110 as shown in FIG. 1. Accordingly, the device 1000 can be implemented at or as at least a part of the terminal device 120, or the network device 110.

As shown, the device 1000 includes a processor 1010, a memory 1020 coupled to the processor 1010, a suitable transmitter (TX) and receiver (RX) 1040 coupled to the processor 1010, and a communication interface coupled to the TX/RX 1040. The memory 1010 stores at least a part of a program 1030. The TX/RX 1040 is for bidirectional communications. The TX/RX 1040 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this disclosure may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 1030 is assumed to include program instructions that, when executed by the associated processor 1010, enable the device 1000 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to FIGS. 2-10. The embodiments herein may be implemented by computer software executable by the processor 1010 of the device 1000, or by hardware, or by a combination of software and hardware. The processor 1010 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 1010 and memory 1020 may form processing means 1050 adapted to implement various embodiments of the present disclosure.

The memory 1020 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 1020 is shown in the device 1000, there may be several physically distinct memory modules in the device 1000. The processor 1010 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 1000 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

In summary, embodiments of the present disclosure may provide the following solutions.

The present disclosure provides a method of communication, comprises: monitoring, at a terminal device in a low power mode, a first signal from a network device; monitoring a second signal from the network device, the second signal being at least a part of a low power wake up signal; in accordance with a determination that the first signal is detected and the second signal is detected, waking up from the low power mode; or in accordance with a determination that the first signal is detected and the second signal is not detected, staying in the low power mode.

In one embodiment, the method as above, further comprises: in accordance with a determination that the first signal is not detected and the second signal is detected, waking up from the low power mode; and performing at least one of: starting a measurement on the first signal, starting a reselection of the second signal, transmitting a miss detection report of the first signal to the network device, or transmitting a measurement result report of the first signal to the network device.

In one embodiment, the method as above, wherein monitoring the second signal comprises: in accordance with a determination that the first signal is detected, monitoring the second signal.

In one embodiment, the method as above, further comprises: in accordance with a determination that the first signal is not detected and the second signal is not detected, determining configuration information from the network device; in accordance with a determination that the configuration information indicates a first value, waking up from the low power mode; and in accordance with a determination that the configuration information is absent or the configuration information indicates a second value, staying in the low power mode.

In one embodiment, the method as above, further comprises: determining that the first signal is detected based on at least one of: an output of a detector of the first signal being greater or not less than a first threshold, a measurement result of the first signal being greater or not less than a second threshold, a number of successfully received first signals during a duration being greater or not less than a first threshold number, or a number of failed received first signals during the duration being less or not greater than a second threshold number.

In one embodiment, the method as above, wherein the measurement result comprises at least one of: received signal strength, received signal power, or signal to interference plus noise ratio (SINR) .

In one embodiment, the method as above, wherein at least one of an occasion for the first signal or an occasion for the second signal is associated with a paging occasion.

In one embodiment, the method as above, wherein the occasion for the first signal is located within a first time period before the paging occasion, or, the occasion for the second signal is located within a second time period before the paging occasion.

In one embodiment, the method as above, wherein a time interval between the occasion for the first signal and the paging occasion is greater than a predefined gap, or, a time interval between the occasion for the second signal and the paging occasion is greater than the predefined gap.

In one embodiment, the method as above, wherein an occasion for the second signal and an occasion for the first signal are continuous at a time domain.

In one embodiment, the method as above, wherein there is a gap between an occasion for the first signal and an occasion for the second signal.

In one embodiment, the method as above, wherein the gap is a fixed value or is preconfigured by the network device.

In one embodiment, the method as above, wherein the gap is unknown to the terminal device, and wherein monitoring the second signal comprises: in accordance with a determination that the first signal is detected, blind monitoring the second signal.

In one embodiment, the method as above, where waking up from the low power mode comprises at least one of a plurality of behaviors: switching on a main radio, switching off a low power radio, stopping monitoring the second signal, monitoring at least one paging occasion, performing a measurement, updating a configuration of the second signal, performing an initial access procedure, or performing a cell reselection procedure.

In one embodiment, the method as above, wherein the second signal is one of a plurality of signals corresponding to the plurality of behaviors.

In one embodiment, the method as above, wherein the first signal is associated with a first identifier (ID) being based on at least one of: an ID of a cell of the network device, an ID of a cell group of the network device, an ID of a public land mobile network of the network device, position information of a paging occasion following the first signal, a tracking area ID associated with the network device, a tracking area code associated with the network device, or an indication provided by the network device for indicating the first signal.

In one embodiment, the method as above, wherein the second signal is associated with a second ID being based on at least one of: an ID of the terminal device, an ID of a group to which the terminal device belongs, a paging probability, or an indication provided by the network device for indicating the second signal.

In one embodiment, the method as above, wherein the second signal is one of a plurality of candidate signals associated with the first signal.

In one embodiment, the method as above, wherein the first signal is used for synchronization.

The present disclosure provides a method of communication, comprises: generating, at a network device, a first signal for a plurality of terminal devices in a low power mode; determining whether to wake up one of the plurality of terminal devices; in accordance with a determination that the one of the plurality of terminal devices is needed to wake up, generating a second signal for the one of the plurality of terminal devices, the second signal being a low power wake up signal; transmitting the first signal to the plurality of terminal devices; and transmitting the second signal to the one of the plurality of terminal devices.

In one embodiment, the method as above, generating a first signal comprises: generating the first signal for the plurality of terminal devices in accordance with a determination that the one of the plurality of terminal devices is needed to wake up

In one embodiment, the method as above, further comprises: receiving, from the one of the plurality of terminal devices, at least one of: a miss detection report of the first signal, or a measurement result report of the first signal.

In one embodiment, the method as above, wherein an occasion for the second signal and an occasion for the first signal are continuous at the time domain.

In one embodiment, the method as above, further comprises: transmitting an indication of the gap to the one of the plurality of terminal devices.

In one embodiment, the method as above, wherein the second signal is one of a plurality of signals corresponding to a plurality of behaviors, the plurality of behaviors comprise: switching on a main radio, switching off a low power radio, stopping monitoring the second signal, monitoring at least one paging occasion, performing a measurement, updating a configuration of the second signal, performing an initial access procedure, or performing a cell reselection.

In one embodiment, the method as above, wherein the second signal is associated with a second ID being based on at least one of: an ID of the one of the plurality of terminal devices, an ID of a group to which the one of the plurality of terminal devices belongs, a paging probability, or an indication provided by the network device for indicating the second signal.

The present disclosure provides a terminal device, comprising: a processor; and a memory storing computer program codes; the memory and the computer program codes configured to, with the processor, cause the terminal device to perform the method implemented at the terminal device discussed above.

The present disclosure provides a network device, comprising: a processor; and a memory storing computer program codes; the memory and the computer program codes configured to, with the processor, cause the network device to perform the method implemented at the network device discussed above.

The present disclosure provides a computer readable medium having instructions stored thereon, the instructions, when executed by a processor of an apparatus, causing the apparatus to perform the method implemented at a terminal device or a network device discussed above.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to FIGS. 2-9. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which 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 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.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A method of communication, comprising:

monitoring, at a terminal device in a low power mode, a first signal from a network device;

monitoring a second signal from the network device, the second signal being at least a part of a low power wake up signal;

in accordance with a determination that the first signal is detected and the second signal is detected, waking up from the low power mode; or

in accordance with a determination that the first signal is detected and the second signal is not detected, staying in the low power mode.
The method of claim 1, further comprising:

in accordance with a determination that the first signal is not detected and the second signal is detected, waking up from the low power mode; and

performing at least one of:

starting a measurement on the first signal,

starting a reselection of the second signal,

transmitting a miss detection report of the first signal to the network device, or

transmitting a measurement result report of the first signal to the network device.
The method of claim 1, wherein monitoring the second signal comprises:

in accordance with a determination that the first signal is detected, monitoring the second signal.
The method of claim 1, further comprising:

in accordance with a determination that the first signal is not detected and the second signal is not detected, determining configuration information from the network device;

in accordance with a determination that the configuration information indicates a first value, waking up from the low power mode; and

in accordance with a determination that the configuration information is absent or the configuration information indicates a second value, staying in the low power mode.
The method of claim 1, further comprising:

determining that the first signal is detected based on at least one of:

an output of a detector of the first signal being greater or not less than a first threshold,

a measurement result of the first signal being greater or not less than a second threshold,

a number of successfully received first signals during a duration being greater or not less than a first threshold number, or

a number of failed received first signals during the duration being less or not greater than a second threshold number.
The method of claim 1, wherein at least one of an occasion for the first signal or an occasion for the second signal is associated with a paging occasion.
The method of claim 1, wherein an occasion for the second signal and an occasion for the first signal are continuous at a time domain.
The method of claim 1, wherein there is a gap between an occasion for the first signal and an occasion for the second signal.
The method of claim 1, where waking up from the low power mode comprises at least one of a plurality of behaviors:

switching on a main radio,

switching off a low power radio,

stopping monitoring the second signal,

monitoring at least one paging occasion,

performing a measurement,

updating a configuration of the second signal,

performing an initial access procedure, or

performing a cell reselection procedure.
The method of claim 1, wherein the first signal is associated with a first identifier (ID) being based on at least one of:

an ID of a cell of the network device,

an ID of a cell group of the network device,

an ID of a public land mobile network of the network device,

position information of a paging occasion following the first signal,

a tracking area ID associated with the network device,

a tracking area code associated with the network device, or

an indication provided by the network device for indicating the first signal.
The method of claim 1, wherein the second signal is associated with a second ID being based on at least one of:

an ID of the terminal device,

an ID of a group to which the terminal device belongs,

a paging probability, or

an indication provided by the network device for indicating the second signal.
A method of communication, comprising:

generating, at a network device, a first signal for a plurality of terminal devices in a low power mode;

determining whether to wake up one of the plurality of terminal devices;

in accordance with a determination that the one of the plurality of terminal devices is needed to wake up, generating a second signal for the one of the plurality of terminal devices, the second signal being a low power wake up signal;

transmitting the first signal to the plurality of terminal devices; and

transmitting the second signal to the one of the plurality of terminal devices.
The method of claim 12, further comprising:

receiving, from the terminal device, at least one of:

a miss detection report of the first signal, or

a measurement result report of the first signal.
The method of claim 12, wherein at least one of an occasion for the first signal or an occasion for the second signal is associated with a paging occasion.
The method of claim 12, wherein the second signal is one of a plurality of signals corresponding to a plurality of behaviors, the plurality of behaviors comprise:

switching on a main radio,

switching off a low power radio,

stopping monitoring the second signal,

monitoring at least one paging occasion,

performing a measurement,

updating a configuration of the second signal,

performing an initial access procedure, or

performing a cell reselection.
The method of claim 12, wherein the first signal is associated with a first identifier (ID) being based on at least one of:

an ID of a cell of the network device,

an ID of a cell group of the network device,

an ID of a public land mobile network of the network device,

position information of a paging occasion following the first signal,

a tracking area ID associated with the network device,

a tracking area code associated with the network device, or

an indication provided by the network device for indicating the first signal.
The method of claim 12, wherein the second signal is associated with a second ID being based on at least one of:

an ID of the terminal device,

an ID of a group to which the terminal device belongs,

a paging probability, or

an indication provided by the network device for indicating the second signal.
A terminal device comprising:

a processor; and

a memory storing computer program codes;

the memory and the computer program codes configured to, with the processor, cause the terminal device to perform the method according to any of claims 1-11.
A network device comprising:

a processor; and

a memory storing computer program codes;

the memory and the computer program codes configured to, with the processor, cause the network device to perform the method according to any of claims 12-17.
A computer readable medium having instructions stored thereon, the instructions, when executed by a processor of an apparatus, causing the apparatus to perform the method according to any of claims 1-17.