Terminal device, network device, and communication method

Abstract

Exemplary embodiments of the present disclosure relate to a method, apparatus, and computer storage medium for communication. In a low power (LP) mode, a terminal device receives an LP synchronization signal from a network device based on at least one of an identity (ID) of a cell group of the network device, an ID of an LP-SS group of the network device, a tracking area ID associated with the network device, or a tracking area code associated with the network device, and detects a wake-up signal from the network device based on the LP synchronization signal. In this way, since the terminal device can achieve and maintain time synchronization with the network device with a certain accuracy, the detection of the wake-up signal can be simplified by using the synchronization, and the detection performance can be enhanced.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure generally relate to the field of communication technologies, and more particularly, to methods, apparatuses, and computer-readable media for communication.

Background Art

[0002] To reduce the power consumption of terminal devices, several technologies have been proposed. For example, a user equipment (UE) may enter a Radio Resource Control (RRC) idle / inactive state to reduce power consumption. However, even in the RRC idle / inactive state, a significant amount of power is consumed on the UE side due to periodic paging monitoring and measurement. Therefore, power saving remains important for devices with limited power, such as Internet of Things (IoT) devices and wearable devices. Thus, further reducing power consumption is beneficial to the UE.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Generally, exemplary embodiments of the present disclosure provide a method, an apparatus, and a computer storage medium for communication.

Means for Solving the Problems

[0004] In a first aspect, a communication method is provided. The method includes receiving, at a terminal device in a low power (LP) mode, an LP synchronization signal from a network device based on at least one of an identity (ID) of a cell group of the network device, an ID of an LP-SS group of the network device, a tracking area ID associated with the network device, or a tracking area code associated with the network device; and detecting, based on the LP synchronization signal, a wake-up signal from the network device.

[0005] In a second aspect, a communication method is provided. The method includes, at a terminal device, detecting a low-power (LP) synchronization signal from a network device; determining, based on the detection of the LP synchronization signal, the state of the terminal device with respect to the coverage of the LP synchronization signal; and determining, based on the state, whether to wake up from the LP mode or report the state to the network device.

[0006] In a third aspect, a communication method is provided. The method includes, at a network device, generating an LP synchronization signal based on at least one of an identity (ID) of a cell group of the network device, an ID of an LP-SS group of the network device, a tracking area ID associated with the network device, or a tracking area code associated with the network device; and transmitting the LP synchronization signal to a terminal device in the LP mode.

[0007] In a fourth aspect, a terminal device is provided. The terminal device includes a processor and a memory. The memory is coupled to the processor and stores instructions. When the instructions are executed by the processor, the instructions cause the terminal device to execute the method according to the first aspect or the second aspect described above.

[0008] In a fifth aspect, a network device is provided. The network device includes a processor and a memory. The memory is coupled to the processor and stores instructions. When the instructions are executed by the processor, the instructions cause the network device to execute the method according to the third aspect described above.

[0009] In a sixth aspect, a computer-readable medium storing instructions is provided. When the instructions are executed by at least one processor, the instructions cause the at least one processor to execute the method according to the first aspect or the second aspect described above.

[0010] It should be understood that the summary part of the invention is not intended to identify important or essential features of the 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 should be readily understood through the following description.

Brief Description of the Drawings

[0011] The above and other objects, features, and advantages of the present disclosure should become more apparent by describing some exemplary embodiments of the present disclosure in more detail in the accompanying drawings.

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[0029] Throughout all the drawings, the same or similar reference numerals represent the same or similar elements.

Mode for Carrying Out the Invention

[0030] The principles of the present disclosure will be described with reference to some exemplary embodiments. It should be understood that these embodiments are described for illustrative purposes only and are useful for those skilled in the art to understand and implement the present disclosure, and do not imply any limitation to the scope of the present disclosure. The embodiments described herein can be implemented in various ways other than those described below.

[0031] In the following description and claims, unless otherwise defined, all technical and scientific terms used have the same meaning as commonly understood by one of ordinary skill in the technical field to which the present disclosure pertains.

[0032] References to "one embodiment", "embodiment", "exemplary embodiment", etc. in the present disclosure indicate that the described embodiment may include a certain specific feature, structure, or characteristic, but not all embodiments need to include such specific feature, structure, or characteristic. Also, these expressions do not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in relation to an embodiment, it is considered within the knowledge of those skilled in the art to affect such feature, structure, or characteristic in relation to other embodiments, whether explicitly described or not.

[0033] In this specification, terms such as "first", "second", etc. may be used to describe various elements, but it should be understood that these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the exemplary embodiments, the first element can be referred to as the second element, and similarly, the second element can be referred to as the first element. As used in this specification, the term "and / or" includes any one or more of the listed items, and all combinations thereof.

[0034] The terms used in this specification are for the sole purpose of describing particular embodiments and are not intended to limit the exemplary embodiments. As used in this specification, the singular forms "a / an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Further, the terms "comprise", "comprising", "have", "having", "include" and / or "including", when used in this specification, define the presence of the described 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.

[0035] In some examples, a value, procedure, or device is referred to as "optimal", "lowest", "highest", "minimum", "maximum", etc. Such descriptions are intended to indicate that a selection is possible from among multiple functional alternatives being used, and it will be understood that such a selection need not be better, smaller, higher, or more preferable than other selections.

[0036] As used herein, the term "communication network" refers to a network that complies with any suitable communication standard such as New Radio (NR), Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA (registered trademark)), High-Speed Packet Access (HSPA), Narrow Band Internet of Things (NB-IoT), etc. Further, the communication between the terminal device and the network device in the communication network may be executed by any suitable generation of communication protocol. The communication protocols include, but are not limited to, the communication protocols of 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 Network or the sixth generation (6G), and / or other protocols known currently or developed in the future. Embodiments of the present disclosure may be applied to various communication systems. Considering the rapid development of communication, it is natural that there will also be future communication technologies and communication systems in which the present disclosure can be implemented. The scope of the present disclosure should not be considered to be limited only to the aforementioned systems.

[0037] In this specification, the term "terminal device" refers to any device having a wireless or wired communication function. Examples of terminal devices include user equipment (UE), personal computers, desktops, mobile phones, cellular phones, smartphones, 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 communications (MTC) devices, vehicle-mounted devices for vehicle-to-everything (V2X) communications (where X means pedestrian, vehicle, or infrastructure / network), devices for Integrated Access and Backhaul (IAB), spacecraft or aircraft in non-terrestrial networks (NTN) including High Altitude Platforms (HAP) and satellites that include Unmanned Aircraft Systems (UAS), Extended Reality (XR) devices including different types of reality such as Augmented Reality (AR), Mixed Reality (MR), Virtual Reality (VR), unmanned aerial vehicles (UAVs), which are aircraft generally known as drones and do not require a human pilot, devices on high speed trains (HSTs), imaging devices such as digital cameras, sensors, gaming devices, music storage / playback devices, or Internet devices that enable wireless / wired Internet access and browsing, etc., but are not limited thereto.The "terminal device" can further have a multicast / broadcast function and support public safety, mission-critical, V2X applications, transparent IPv4 / IPv6 multicast delivery, IPTV, smart TV, wireless services, wireless software delivery, group communication, and IoT applications. Also, one or more subscriber identity modules (SIMs), known as multi-SIM, may be incorporated. The term "terminal device" can be used interchangeably with UE, mobile station, subscriber equipment, mobile terminal, user terminal, or wireless device.

[0038] As used herein, the term "network device" refers to a device capable of providing or hosting a cell or coverage with which a terminal device can communicate. Examples of network devices include, but are not limited to, satellites, unmanned aircraft system (UAS) platforms, Node B (NodeB or NB), Evolved NodeB (eNodeB or eNB), next-generation NodeB (gNB), transmission reception point (TRP), remote radio unit (RRU), radio head (RH), remote radio head (RRH), IAB node, femto node, low-power nodes such as pico nodes, reconfigurable intelligent surface (RIS), etc.

[0039] In one embodiment, the terminal device may be connected to 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 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 an eNB, and the second RAT device is a gNB. Information related to different RATs may be transmitted from at least one of the first network device and the second network device to the terminal device. In one embodiment, the first information may be transmitted from the first network device to the terminal device, and the second information may be directly transmitted from the second network device to the terminal device or transmitted via the first network device. In one embodiment, information related to the settings of the terminal device set by the second network device may be transmitted from the second network device via the first network device. Information related to the re - settings of the terminal device set by the second network device may be directly transmitted from the second network device to the terminal device or transmitted via the first network device.

[0040] The communications discussed in this specification may conform to any suitable standard, including, but not limited to, New Radio (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) for mobile communications. Further, the communications may be performed according to any generation of communication protocol known currently or developed in the future. Examples of communication protocols include, but are not limited to, the communication protocols of the first generation (1G), second generation (2G), 2.5G, 2.85G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G), and sixth generation (6G). The techniques described in this specification may be used not only for the above wireless networks and wireless technologies but also for other wireless networks and wireless technologies. Embodiments of the present disclosure may be performed according to any generation of communication protocol known currently or developed in the future. Examples of communication protocols include, but are not limited to, the communication protocols of the first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G), 5.5G, 5G-Advanced Network, or sixth generation (6G) network.

[0041] The terminal device or the network device may have an artificial intelligence (AI) or machine learning function. Generally, it includes a model that can learn from a large number of data collected for a specific function and be used to predict some information.

[0042] The terminal device or network device may function in a plurality of frequency ranges, such as, for example, FR1 (410 MHz to 7125 MHz), FR2 (24.25 GHz to 71 GHz), a frequency band higher than 100 GHz, terahertz (THz), etc. Furthermore, it can function in licensed / unlicensed / shared spectrum. The terminal device may have multiple connections with the network device in a scenario of multi-radio dual connectivity (MR-DC) application. The terminal device or network device can function in full-duplex, flexible-duplex, and cross-divided duplex modes.

[0043] Embodiments of the present disclosure may be executed in a test device such as, for example, a signal generator, a signal analyzer, a spectrum analyzer, a network analyzer, a test terminal device, a test network device, or a channel emulator.

[0044] Embodiments of the present disclosure may be executed in accordance with any generation of communication protocol known currently or developed in the future. Examples of communication protocols include, but are not limited to, the communication protocols of 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 Network, or the sixth generation (6G) network.

[0045] As used herein, the term "circuit" may mean a hardware circuit and / or a combination of a hardware circuit and software. For example, a circuit may be a combination of an analog hardware circuit and / or a digital hardware circuit with software / firmware. As a further example, a circuit may be any portion of a hardware processor with software, such as a digital signal processor, software, and memory, that cooperate to provide various functions to a device such as a terminal device or a network device. In yet another example, a circuit may be a hardware circuit and / or a processor, such as a microprocessor or a portion of a microprocessor, that requires software / firmware for operation but may not have software present when not required for operation. As used herein, the term "circuit" encompasses a mere hardware circuit or processor, or a portion of a hardware circuit or processor, and its (or their) attendant software and / or firmware implementation.

[0046] As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "including" and its variations are to be construed as open-ended terms meaning "including but not limited to". The term "based on" is to be construed as "based at least in part on". The terms "one embodiment" and "an embodiment" are to be construed as "at least one embodiment". The term "another embodiment" is to be construed as "at least one other embodiment". The terms "first", "second", etc. may refer to different objects or the same object. There may be other definitions, explicit or implicit, in the following content.

[0047] In some examples, a value, procedure, or apparatus is referred to as "optimal", "lowest", "highest", "minimum", "maximum", etc. Such descriptions are intended to indicate that a selection is possible from among a plurality of functional alternatives being used, and it will be understood that such a selection need not be better, smaller, higher, or more preferable than other selections.

[0048] As described above, in the case of a UE in the RRC idle / inactive state, on the UE side, a significant amount of power is consumed by periodic paging monitoring and measurement, which is an important issue for power-constrained devices such as IoT devices and wearable devices.

[0049] In Release 18, a Lower Power Wake-up Signal (LP-WUS) has been proposed. In Release 18, it is possible to study and evaluate technologies for low-power signals and low-power receivers in order to enable extremely low power consumption and low wake-up latency.

[0050] However, when the UE enters the low-power mode and turns off its main radio, it becomes unable to maintain synchronization with the network side based on the Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSB), or Tracking Reference Signal (TRS). Therefore, it is necessary to consider and define the synchronization signal settings for UEs in the low-power mode.

[0051] Embodiments of the present disclosure provide a communication solution. In this solution, a Low-Power Synchronization Signal (LP-SS) different from PSS / SSS is proposed. The LP-SS can be associated with information related to a network device and can include an amplitude modulation sequence. By doing so, synchronization with the network side in the low-power mode can be maintained, and communication efficiency can be improved. The principle and implementation of the present disclosure will be described in detail below with reference to the drawings.

[0052] FIG. 1 shows an exemplary communication system 100 in which some embodiments of the present disclosure can be implemented. The communication network 100 includes a network device 110-1 and optionally a network device 110-2 (collectively or individually referred to as network device 110). The communication network 100 further includes a terminal device 120. The network device 110 can provide services to the terminal device 120.

[0053] In system 100, it is assumed that the terminal device 120 is within the coverage of the network device 110-1. In some examples, the link from the network device 110-1 to the terminal device 120 is referred to as the downlink (DL), and the link from the terminal device 120 to the network device 110-1 is referred to as the uplink (UL). In the downlink, the network device 110-1 is a transmitting (TX) device (or transmitter), and the terminal device 120 is a receiving (RX) device (or receiver). In the uplink, the terminal device 120 is a transmitting (TX) device (or transmitter), and the network device 110-1 is a receiving (RX) device (or receiver). In some embodiments, the network device 110 and the terminal device 120 may communicate via a direct link / channel. The DL may include one or more logical channels. The one or more logical channels include, but are not limited to, the physical downlink control channel (PDCCH) and the physical downlink shared channel (PDSCH). The UL may include one or more logical channels. The one or more logical channels include, but are not limited to, the physical uplink control channel (PUCCH) and the physical uplink shared channel (PUSCH). As used herein, the term "channel" may refer to a carrier or a part of a carrier composed of a continuous set of resource blocks (RBs), where channel access procedures are performed within the shared spectrum.

[0054] In some cases, the terminal device 120 may move into the coverage of the network device 110-2 when it is outside the coverage of the network device 110-1. In some embodiments, the network device 110-1 and the network device 110-2 may belong to the same cell group or may be located in different cell groups. In some embodiments, the network device 110-1 and the network device 110-2 may have the same tracking area code (TAC), or may have different tracking area codes.

[0055] In some embodiments, the terminal device 120 may be in the main mode. In the context of the present disclosure, the terms "main mode", "main radio", and "main receiver" can be used interchangeably. The terminal device 120 may perform normal DL / UL transmissions in the main mode.

[0056] In some embodiments, the terminal device 120 may be in the idle / inactive mode. For example, the same coverage as normal DL / UL transmissions cannot be provided, and the terminal device 120 may receive a wake-up signal (WUS) with a wake-up receiver (WUR).

[0057] In some embodiments, the main targets of the WUS or WUR may be power-sensitive small form factor devices including IoT use cases (industrial sensors, controllers, etc.) and wearables. In some examples, the configuration of a low-power wake-up receiver may be considered and evaluated. In some examples, the design of a wake-up signal that supports the wake-up receiver may be considered and evaluated. In some examples, the changes to the L1 procedures and upper layer protocols required to support the wake-up signal may be considered and evaluated. In some examples, it has been proposed to examine the potential power saving gain of the UE compared to existing power saving mechanisms, the availability of its coverage, and the impact on latency. For example, it may include the power consumption of the network, coexistence with non-low-power WUR UEs, and the impact on the system such as the network coverage / capacity / resource overhead.

[0058] In some embodiments, the terminal device 120 may be in the LP mode. In the context of the present disclosure, the terms "LP mode", "low-power mode", "ultra-low-power mode", "low-power radio", "ultra-low-power radio", "low-power receiver", and "ultra-low-power receiver" can be used interchangeably.

[0059] In the present disclosure, the term "low power (LP) mode" may refer to a mode in which the terminal device 120 does not need to perform at least one of paging monitoring, cell selection and reselection, measurement based on SSB or channel state information-reference signal (CSI-RS), PDCCH monitoring, UL transmission, etc., and the terminal device 120 needs to perform monitoring and / or detection of LP signals.

[0060] In some embodiments, when the terminal device 120 is in the main mode, it may perform at least one of paging monitoring, cell selection and reselection, measurement based on SSB or CSI-RS, PDCCH monitoring, or UL transmission.

[0061] In some embodiments, the terminal device 120 may enter the LP mode by turning off the main radio. For example, the terminal device 120 can turn off its main radio and turn on the LP radio. Here, the LP radio is used to receive LP signals, and the main radio is used to receive or transmit signals other than LP signals.

[0062] In the present disclosure, the LP signal may include LP-SS and / or LP-WUS. In some embodiments, LP-SS may be used for synchronization and measurement, LP-SS may be cell-specific, and may be an always-on signal. In some embodiments, LP-WUS may be used to indicate to the terminal device 120 to wake up from the LP mode and start monitoring paging information, LP-WUS may be UE group-specific (or UE-specific), and may be an on-demand signal.

[0063] Thus, two types of LP signals are introduced, and LP-SS may be used for synchronization when the terminal device 120 is in the LP mode.

[0064] In some embodiments, the LP-SS may be based on at least one amplitude modulation sequence, and the sequence may include higher amplitude symbols and lower amplitude symbols. In some examples, the amplitude modulation may include amplitude shift keying (ASK) modulation or on-off keying (OOK) modulation. Specifically, on-off keying (OOK) modulation is widely considered due to its very simple receiver configuration and ultra-low power consumption. In OOK modulation, the receiver only needs to detect the envelope or energy of the time-domain signal at a relatively low sampling rate without complex baseband processing. As an example, in the following disclosure, OOK modulation is considered as one of the amplitude modulation methods. The OOK modulation sequence may include at least one OOK on symbol and at least one OOK off symbol. The present disclosure is not limited in this regard.

[0065] In some embodiments, the LP-WUS may be based on at least one amplitude modulation sequence such as an OOK modulation sequence, or may be based on at least a Gold sequence.

[0066] Thus, the LP-SS may be based on at least one OOK modulation sequence, which can facilitate the reception of LP signals. It should be understood that the LP-SS is different from the PSS or SSS. For example, since OOK detection is more robust to time errors than orthogonal frequency division multiplexing (OFDM) detection, the terminal device 120 may not need to achieve very accurate time synchronization with the network side like the SSB / TRS. For example, the terminal device 120 may not need to obtain at least the slot index and the OFDM symbol index (or even the subframe index). The reason is that these indexes may not be useful for OOK detection. Therefore, how to design the LP-SS and related procedures is an important issue.

[0067] In some embodiments, the LP signal (LP-SS or LP-WUS) occupies a set of time / frequency resources of the serving cell. FIG. 2A shows a schematic diagram of resources 210 occupied by an LP signal that can be used in some exemplary embodiments of the present disclosure. In the frequency domain, the resources allocated to the LP signal 212 may overlap with a set of PRBs or subcarriers. That is, a set of PRBs or subcarriers may be shown for the terminal device 120, and the frequency resources of the set of PRBs or subcarriers are used by the LP signal 212. In the time domain, the resources allocated to the LP signal 212 may overlap with a set of OFDM symbols. That is, a set of OFDM symbols may be shown for the terminal device 120, and the time resources of the set of OFDM symbols are used by the LP signal 212.

[0068] In some examples, OOK modulation is used to generate the LP signal, and the OOK symbol can be an OOK on-symbol (represented by logical "1") or an OOK off-symbol (represented by logical "0"). The OOK on-symbol has relatively high power, and the OOK off-symbol has zero power or relatively low power.

[0069] It should be understood that the OOK symbol may or may not be equal to the OFDM symbol. FIGS. 2B-2C show schematic diagrams of OOK symbols that can be used in some exemplary embodiments of the present disclosure.

[0070] As shown in FIG. 2B, the OOK on-symbol or the OOK off-symbol may have a duration equal to the duration of the OFDM symbol. In this case, the OOK on-symbol and the OOK off-symbol are realized by a non-zero power OFDM symbol and a zero power OFDM symbol, respectively.

[0071] As shown in FIG. 2C, the OOK on symbol or the OOK off symbol may have a duration shorter than that of the OFDM symbol. In this case, the OOK on symbol and the OOK off symbol can be realized by DFT-s-OFDM or by independent time-domain generation.

[0072] In some embodiments, the LP signal may include a sequence of OOK symbols formed by at least one OOK on symbol and at least one OOK off symbol, such as "1010...1" shown in FIGS. 2B-2C.

[0073] It should be noted that in the present disclosure, unless otherwise specified, the term "OFDM symbol" refers to a CP-OFDM symbol or any variant of the OFDM symbol, such as GI-OFDM, zero CP OFDM, unique word OFDM, etc.

[0074] 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 disclosure, the terms "power", "energy", "amplitude", and "intensity" may be used interchangeably.

[0075] Communication between the network device 110-1 and the terminal device 120 in the system 100 may be carried out, for example, in accordance with any suitable communication protocol. Communication protocols include, but are not limited to, cellular communication protocols such as the first generation (1G), second generation (2G), third generation (3G), fourth generation (4G), and fifth generation (5G), wireless local area network communication protocols such as Institute of Electrical and Electronics Engineers (IEEE) 802.11, and / or any other protocol known currently or developed in the future. Further, the communication may utilize any suitable wireless communication technology. Wireless communication technologies include, but are 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 technology known currently or developed in the future.

[0076] Embodiments of the present disclosure can be applied to any suitable scenario. For example, embodiments of the present disclosure can be implemented in an NR device with reduced capabilities. Alternatively, embodiments of the present disclosure can be implemented in any of the following: New Radio (NR) multiple-input and multiple-output (MIMO), NR Sidelink Enhancements, NR systems at frequencies above 52.6 GHz, NR operation expansion up to 71 GHz, narrow band-Internet of Things (NB-IoT) / enhanced Machine Type Communication (eMTC) in non-terrestrial networks (NTN), NTN, UE power saving function enhancement, NR coverage expansion, NB-IoT and LTE-MTC, Integrated Access and Backhaul (IAB), NR multicast broadcast service, or enhanced multi-radio dual connectivity.

[0077] It should be understood that the number of devices shown in FIG. 1 (i.e., network device 110 and terminal device 120), their connection relationships and types are for illustrative purposes only and do not imply any limitation. System 100 may include any suitable number of devices suitable for implementing embodiments of the present disclosure.

[0078] In embodiments of the present disclosure, the terminal device can receive LP-SS in the LP mode. First, refer to FIG. 3. FIG. 3 shows a signaling chart illustrating a communication process 300 according to some exemplary embodiments of the present disclosure. For the purpose of discussion only, process 300 will be described with reference to FIG. 1. Process 300 may involve terminal device 120, network device 110 (e.g., network device 110-1 or network device 110-2).

[0079] In the present disclosure, two types of LP signals, LP-SS and LP-WUS, are proposed. LP-SS may be used for synchronization, measurement, and / or beam measurement. LP-SS may be cell-specific or cell-group-specific (for example, cells associated with the same TAC, i.e., tracking area code, can have the same settings for LP-SS). And the terminal device 120 may expect LP-SS to be always transmitted at each opportunity of LP-SS. LP-WUS may be used to notify the terminal device 120 of wake-up information, for example, to notify the terminal device 120 to wake up from the LP mode, or to notify the terminal device 120 to stay in the LP mode, or to notify the terminal device 120 of new settings of LP-SS.

[0080] As shown in FIG. 3, the network device 110 generates (310) an LP synchronization signal (LP-SS). In some embodiments, LP-SS is different from PSS or SSS.

[0081] In some exemplary embodiments, LP-SS may include an amplitude modulation sequence. For example, LP-SS may include an OOK sequence including at least one OOK on-symbol and at least one OOK off-symbol.

[0082] In some embodiments, the sequence of LP-SS may be generated based on at least one amplitude modulation sequence (such as an OOK sequence) associated with the identity associated with the network device 110. In some examples, the identity may be at least one of the identity (ID) of the cell of the network device 110, the ID of the cell group of the network device 110, the ID of the LP-SS group of the network device 110, the tracking area ID associated with the network device 110, the tracking area code associated with the network device 110, or an indication provided by the network device 110 to indicate LP-SS.

[0083] In some embodiments, the sequence of the LP-SS may be generated based on one or more amplitude modulation sequences, for example, based on a first OOK sequence and a second OOK sequence, and at least one of the first OOK sequence and the second OOK sequence is associated with an identity.

[0084] In some exemplary embodiments, the LP-SS may be one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of a network device or quasi-collocated (QCL) with a plurality of SSBs transmitted by the network device 110. In some examples, the network device 110 may configure a set of LP-SSs including a plurality of signals for the terminal device 120.

[0085] In some embodiments, the plurality of signals in the LP-SS set may be based on a common amplitude modulation sequence. In some examples, the plurality of signals in the LP-SS set may be represented as the same sequence and transmitted in different time resources. For example, different time resources refer to different subframes within a system frame.

[0086] In some embodiments, the plurality of signals in the LP-SS set may be based on different amplitude modulation sequences. In some examples, each of the plurality of signals may be associated with at least one of a subframe index, a slot index, or an index of the plurality of signals. For example, different signals in the LP-SS set are associated with different subframe indices. For example, different signals in the LP-SS set are associated with different slot indices. For example, each of the plurality of signals is associated with an index of the LP-SS set (i.e., an index of the plurality of signals).

[0087] In some examples, different signals in the LP-SS set may be associated with different signal indices.

[0088] In some embodiments, the network device 110 may generate the LP-SS based on its TX beam and the LP-SS set.

[0089] Alternatively, or additionally, the network device 110 may set or indicate a set of time resources for the LP-SS to the terminal device 120. In some embodiments, the network device 110 may indicate a set of time resources to the terminal device 120 by at least one of an initial hyperframe number, a transmission period of the LP synchronization signal, a hyperframe offset, a frame offset, a subframe offset, or a slot offset. In some examples, the transmission period may be equal to a plurality of hyperframes or a plurality of frames.

[0090] For example, the network device 110 may transmit an indication of the initial hyperframe number to the terminal device 120, and the indication of the initial hyperframe number may be transmitted by system information, RRC signaling, or packet data convergence protocol (PDCP) parameters.

[0091] The network device 110 transmits (320) the LP-SS 322 to the terminal device 120. In some exemplary embodiments, the network device 110 may transmit the LP-SS 322 in one of the set of time resources. In some exemplary embodiments, the LP-SS 322 may be one of a plurality of signals corresponding to the TX beam, and the LP-SS 322 is transmitted through the TX beam.

[0092] On the other side of the communication, the terminal device 120 in the LP mode receives (324) the LP-SS 322.

[0093] Alternatively, or in addition, the terminal device 120 may enter the LP mode from the main mode. In some examples, the terminal device 120 may receive control information that notifies the terminal device 120 to enter the LP mode, and the terminal device 120 may enter the LP mode based on the control information.

[0094] In some embodiments, the terminal device 120 may enter the LP mode by turning off the main mode. And the terminal device 120 may not need to perform at least one of paging monitoring, cell selection or reselection, measurement based on PSS, SSS or CSI-RS, PDCCH monitoring, or uplink transmission.

[0095] In some exemplary embodiments, the terminal device 120 may receive the LP-SS 322 based on an identity associated with the LP-SS 322. In some examples, the identity may be at least one of the ID of the cell of the network device 110, the ID of the cell group of the network device 110, the ID of the LP-SS group of the network device 110, the tracking area ID associated with the network device 110, the tracking area code associated with the network device 110, or an indication provided by the network device 110 to indicate the LP-SS.

[0096] In some exemplary embodiments, the LP-SS 322 is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of the network device 110 or are quasi-collocated with a plurality of SSBs transmitted by the network device 110. In this case, the terminal device 120 may determine the index of the TX beam or SSB based on the received LP-SS 322.

[0097] Alternatively, or in addition, the terminal device 120 may determine a set of time resources and receive the LP-SS 322 in one of the set of time resources.

[0098] In some exemplary embodiments, the set of time resources may be determined based on at least one of a hyper frame number (HFN), a transmission period of the LP synchronization signal, a hyper frame offset, a frame offset, a sub-frame offset, or a slot offset.

[0099] In some embodiments, the transmission period may be equal across multiple hyper frames. In some embodiments, the terminal device 120 may determine the HFN based on the initial hyper frame number.

[0100] In some examples, the terminal device 120 may receive an indication of the initial hyper frame number in the serving cell before entering the LP mode. The indication of the initial hyper frame number may be transmitted from the serving cell while the terminal device 120 is in the main mode. The network device in the serving cell may be the network device 110, or may be another device different from the network device 110. The present disclosure is not limited in this regard.

[0101] In some examples, the terminal device 120 may determine the initial hyper frame number based on the time when the terminal device 102 receives control information instructing the terminal device 120 to enter the LP mode.

[0102] In some embodiments, the terminal device 120 first determines that the HFN is equal to the initial hyper frame number, and then updates the HFN by incrementing it by 1 when the system frame number (SFN) returns from 1023 to 0.

[0103] In some embodiments, the transmission period may be equal for a plurality of frames. In some examples, the set of time resources may be further determined based on the ID of the LP-SS group including the LP-SS 322. The LP-SS group includes at least one LP-SS. In some examples, the ID of the LP-SS group may be the index of the LP-SS group. In some examples, the LP-SS group may be implemented as a set of LP-SSs, and the present disclosure is not limited in this regard. As described above, the LP signal may include the LP-SS 322 and / or at least one LP-WUS 332. In some examples, when the LP signal includes the LP-SS 322 and at least one LP-WUS 332, the ID of the LP-SS group may be equal to the ID of the LP signal group including the LP signal. In some examples, when the LP signal includes the LP-SS 322, the ID of the LP-SS group may be equal to the ID of the LP signal group.

[0104] In this way, the terminal device 120 can achieve and maintain time synchronization with the network device 110 with a certain accuracy.

[0105] The network device 110 transmits (330) a wake-up signal 332 to the terminal device 120. In some embodiments, the wake-up signal 332 may be UE-specific or UE-group-specific and may be an on-demand signal. In this way, the overhead can be reduced.

[0106] In some examples, the network device 110 may generate the wake-up signal 332 based on the ID of the terminal device 120, or the ID of the group to which the terminal device 120 belongs, or the ID associated with the terminal device 120 and indicated by the network device 110. In some examples, the wake-up signal 322 may also be referred to as a low-power wake-up signal (LP-WUS), and the present disclosure is not limited in this regard.

[0107] In some exemplary embodiments, the wake-up signal 332 may stay in the LP mode, wake up from the LP mode, or notify the terminal device 120 of at least one of the LP-SS settings transmitted by the network device 110.

[0108] In some exemplary embodiments, the wake-up signal 332 may be transmitted at one of a plurality of opportunities within the window.

[0109] Alternatively, or in addition, the network device 110 may set or indicate a window to the terminal device 120. For example, the start point and the length of the period of the window may be indicated to the terminal device 120.

[0110] In some embodiments, the plurality of opportunities may be associated with a plurality of LP-SSs. For example, the plurality of opportunities may be associated with a plurality of signals within the LP-SS set as described above. In some examples, there are N LP-SS signals in the LP-SS set, there are N opportunities in the window, and the i-th opportunity may be associated with the i-th LP-SS signal. Here, N is an integer, and i is an integer from 0 to N.

[0111] In some exemplary embodiments, the wake-up signal 332 may be transmitted through the TX beam in the same manner as in the case of the LP-SS 322.

[0112] The terminal device 120 detects the wake-up signal based on the received LP-SS 322 (326). Alternatively, the terminal device 120 receives the wake-up signal 332 (334).

[0113] In some exemplary embodiments, the wake-up signal 332 at one of the multiple opportunities is associated with the LP-SS 322 among the multiple signals, and the rank of one of the multiple opportunities among the multiple opportunities is the same as the rank of the LP-SS 322 among the multiple signals. In some examples, when the terminal device 120 receives the i-th LP-SS among the multiple signals, the terminal device 120 may expect the wake-up signal at the i-th opportunity among the multiple opportunities, and accordingly, the terminal device 120 detects the wake-up signal at the i-th opportunity. Here, i is an integer.

[0114] In this way, the terminal device 120 can simplify the detection of the wake-up signal 322 by utilizing the synchronization realized by the LP-SS 322, and can enhance the detection performance.

[0115] To deepen the understanding, several details will be described below with reference to FIGS. 4 to 12.

[0116] In some exemplary embodiments, the network device 110 may generate the LP-SS 322 based on the information associated with the network device 110. Accordingly, the terminal device 120 may receive the LP-SS 322 based on the information associated with the network device 110. In some embodiments, the information associated with the network device 110 may include at least one of the identity (ID) of the cell of the network device 110, the ID of the cell group of the network device 110, the ID of the LP-SS group of the network device 110, the tracking area ID associated with the network device 110, the tracking area code associated with the network device 110, or the indication provided by the network device 110 to indicate the LP-SS.

[0117] In some examples, the ID of a cell of the network device 110 may be represented as a cell ID, the ID of a cell group of the network device 110 may be represented as a cell group ID, and the ID of an LP-SS group of the network device 110 may be represented as an LP-SS group ID.

[0118] For example, LP-SS 322 may be based on a tracking area code (TAC) that may be associated with a group of network devices. In this way, as long as the terminal device 120 stays within the group of network devices associated with the TAC, the LP-SS does not change even if the terminal device 120 moves from one cell to another cell. Therefore, signaling overhead and power consumption due to LP-SS reconfiguration can be reduced, and communication efficiency can be improved.

[0119] The information associated with the network device 110 in the present disclosure may be in other forms such as a value, an integer, an index, etc. indicated by the network device 110. For example, the information associated with the network device 110 may be called an identity, and it should be understood that the present disclosure is not limited in this regard.

[0120] In some embodiments, LP-SS 322 may be

Number

[0121] In some examples, the sequence of the LP-SS (sequence

Number

Number

Number

Number

Number

Number

[0122] In the above formula,

Number

Number

Number

Number

Number

[0123] As another example,

Number

Number

Number

[0124] In the above formula,

Number

Number

Number

Number

Number

[0125] In some examples, the identity is

Number

Number

[0126] In equations (6) to (8), [Number] is a function that returns the largest integer less than or equal to the input as the output, and [Number] is a function that returns the smallest integer greater than or equal to the input as the output.

[0127] As shown in the above example, the initialization value of the m-sequence ( [Number] in equation (3), or [Number] ) is a fixed value. However, the initialization value of the m-sequence (also referred to as the initialization sequence) is the identity [Number] may be associated therewith. For example, the initialization sequence may be equal to the binary format of the identity, or the first or last plurality of binary digits of the identity, or

Number

[0128] For example,

Number

Number

Number

Number

Number

Number

Number

Number

[0129] It should be understood that the above content is for illustrative purposes only and does not imply any limitation on the scope of the present disclosure.

[0130] In some examples, the sequence of LP-SS (sequence

Number

Number

Number

Number

Number

Number

[0131] In some embodiments, the m-sequence can also be based on the ID of the LP-SS set. In some embodiments, the m-sequence can also be based on the index of the LP-SS within the LP-SS set, or the subframe index or slot index associated with the LP-SS.

[0132] As described above, the LP signal may include LP-SS and / or LP-WUS. In some embodiments, LP-WUS may be based on information associated with the terminal device 120. In some examples, the information associated with the terminal device 120 may include at least one of the ID of the terminal device 120, the ID of the group of the terminal device 120, or an instruction provided by the network device 110 to indicate LP-WUS. In some examples, the ID of the terminal device 120 may be represented as a UE-ID, the ID of the group of the terminal device 120 may be represented as a UE group ID, and the instruction provided by the network device 110 to indicate LP-WUS may be represented as an ID indicated by the network device 110.

[0133] In some embodiments, LP-WUS may similarly be based on at least one candidate sequence. In some examples, at least one candidate sequence of LP-WUS is used to notify the terminal device 120 to wake up from the LP mode (i.e., to start receiving or transmitting a specific type of physical channel / signal such as PDCCH, paging, etc.) or not to wake up, i.e., to notify the terminal device 120 not to receive or transmit a specific type of physical channel / signal. The at least one candidate sequence is determined based on the UE-ID or UE group ID, or the ID indicated by the network device 110. Thus, the terminal device 120 may be indicated with a plurality of IDs to determine a plurality of sequences of LP-WUS.

[0134] Alternatively, the at least one candidate sequence may be determined based on paging settings. For example, the sequence may be associated with the index of the paging frame or the index of the paging opportunity.

[0135] In some examples, the at least one candidate sequence may be at least one m-sequence or Gold sequence generated based on the UE-ID or UE group ID.

[0136] Alternatively, or in addition, LP-SS and LP-WUS may share the same frequency region setting. For example, LP-SS and LP-WUS may occupy the same frequency region resources. In this case, the complexity at the terminal device 120 can be reduced and the power consumption can be cut down.

[0137] Alternatively, or in addition, different time region settings may be set for LP-SS and LP-WUS. Specifically, different periods may be set for them.

[0138] To deepen the understanding, reference is made here to FIG. 4. FIG. 4 shows a schematic diagram of different periods 400 of LP-SS and LP-WUS according to some embodiments of the present disclosure. As shown in FIG. 4, LP-SS may have 512 system frames or a period of 5.12 seconds, and LP-WUS may have 2 system frames or a period of 20 milliseconds.

[0139] In some examples, when LP-SS and LP-WUS overlap or partially overlap in the time region, the terminal device 120 may determine (or assume) that LP-WUS is not transmitted.

[0140] The periods here are for illustrative purposes only and not limiting. Some detailed descriptions regarding the period of LP-SS are described below.

[0141] In some embodiments of the present disclosure, LP-SS may be one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of the network device 110 or are quasi-co-located (QCL) with a plurality of synchronization signal blocks (SSB) transmitted by the network device 110.

[0142] In this case, LP-SS may be used for beam-based transmission. For example, since it is assumed that the LP receiver may use a passive omnidirectional antenna, i.e., does not use an RX beam, beam management based on LP-SS may be supported. In some examples, there may be only one RX beam in the terminal device 120.

[0143] In some embodiments, the network device 110 may respectively configure a plurality of signals associated with a plurality of TX beams, or a plurality of signals quasi-collocated with a plurality of SSBs transmitted by the network device 110. In some examples, the plurality of signals may be referred to as an LP-SS set. The network device 110 may configure an LP-SS set for the terminal device 120, and the LP-SS set may include one or more LP-SSs.

[0144] In some exemplary embodiments, the LP-SS set may be restricted within a system frame. In other words, the plurality of signals do not cross the boundary of two consecutive system frames, and thus the same system frame number (SFN) is associated with the LP-SS set. In this way, regardless of the TX beam, the same SFN may be determined based on the LP-SS set. In other words, all LP-SSs within the LP-SS set are associated with the same SFN, and the terminal device 120 may determine the SFN regardless of which LP-SS is detected.

[0145] In some exemplary embodiments, the plurality of signals within the LP-SS set may be used for beam measurement.

[0146] In some examples, the LP-SS set includes multiple signals (also referred to as multiple LP-SSs), and each of the multiple signals is associated with a TX beam or is quasi-collocated with an SSB (e.g., associated with an SSB index). In some examples, the terminal device 120 can also refine the RX beam based on the multiple signals (if any). This is beneficial for the terminal device 120 to speed up its beam measurement after waking up. The reason is that it may not be necessary to blindly detect all SSBs to find a more appropriate beam.

[0147] In some embodiments, the multiple signals within the LP-SS set may be based on the same sequence. For example, the multiple signals may be regarded as N repetitions of the LP-SS.

[0148] In some examples, the index (such as rank) of the LP-SS within the LP-SS set may be determined based on the time resource of the LP-SS. For example, assuming that there are N LP-SSs in the LP-SS set from index 0 to index N - 1 and the N LP-SSs occupy N different periods (different subframes, etc.), if the terminal device 120 receives an LP-SS in the nth subframe among the N different subframes, the terminal device 120 may determine that the received LP-SS has an index of N - 1.

[0149] To deepen the understanding, reference is now made to FIG. 5. FIG. 5 shows a schematic diagram of different periods 500 of an LP-SS set according to some embodiments of the present disclosure. As shown in FIG. 5, the frame 510 of SFNi is used for transmitting the LP-SS, and there are four periods 522 to 528 for four LP-SSs. If the terminal device 120 receives an LP-SS in period 522, the terminal device 120 can determine that the index of the received LP-SS is "0". If the terminal device 120 receives an LP-SS in period 526, the terminal device 120 can determine that the index of the received LP-SS is "2".

[0150] In this way, since the terminal device 120 only needs to blindly detect one LP-SS, the complexity of the terminal device 120 can be reduced.

[0151] In some embodiments, the plurality of signals in the LP-SS set may be based on different sequences. For example, each of the plurality of signals may be associated with the index of the LP-SS set. Also, each of the plurality of signals is associated with a subframe index or a slot index. In this way, the terminal device 120 may determine which LP-SS set the received LP-SS belongs to based on the relevant index of the LP-SS set. Then, the terminal device 120 may determine which specific signal is received based on the associated subframe index or slot index.

[0152] In some examples, the

Number

[0153] In this way, although the terminal device 120 needs to detect more LP-SSs, the terminal device 120 may determine the subframe index or slot index based on the index of the detected LP-SS.

[0154] With the LP-SS, the terminal device 120 can realize and maintain time synchronization with the network side with a certain accuracy. Therefore, the terminal device 120 can simplify the detection of LP-WUS by using the synchronization and enhance the detection performance.

[0155] In some exemplary embodiments, the transmission period of the LP-SS may be indicated to the terminal device 120. In some embodiments, the transmission period may also be regarded as the period of the LP-SS set.

[0156] In some exemplary embodiments, the period may be equal to a plurality of hyperframes. For example, the period may be a hyperframe of N1, where the hyperframe includes 1024 frames with indices from SFN 0 to SFN 1023, and N1 is an integer greater than 0.

[0157] In some embodiments, at least one of a hyperframe offset n1, a frame offset n2, a subframe offset n3, and a slot offset n4 may be indicated to the terminal device 120.

[0158] In some examples, a period N1, a hyperframe offset n1, and a frame offset n2 are indicated, and the LP-SS set may be transmitted in the system frame of SFN n2 of the hyperframe of HFN n, where (n mod N1)=n1.

[0159] In some examples, the terminal device 120 may receive an initial HFN from the serving cell before entering the LP mode, and the initial HFN may be indicated by system information, or RRC signaling, or PDCP parameters. And after the terminal device 120 enters the LP mode, it may maintain the count of the HFN. In some other examples, the terminal device 120 may determine the initial HFN based on the time when the control information indicating that the terminal device 120 is to enter the LP mode is received. Specifically, when the control information is received in the system frame of SFNi, at that time the terminal device 120 may determine that the current hyperframe to which SFNi belongs is the initial hyperframe, and the associated initial HFN is a predetermined integer such as 0, 512, or 1023. And after the terminal device 120 enters the LP mode, it may maintain the count of the HFN.

[0160] In some examples, a period N1 = 1 and a frame offset n2 are indicated, and the LP-SS set may be transmitted in the system frame of SFN n2 of each hyperframe.

[0161] In some examples, a subframe offset n3 is also shown, and the LP-SS set may be transmitted in subframe n3 of the system frame of SFN n2.

[0162] In some examples, a slot offset n4 is also shown, and the LP-SS set may be transmitted in slot n4 of subframe n3.

[0163] To deepen the understanding, reference is made here to FIG. 6. FIG. 6 shows a schematic diagram of the time resource 600 of the LP-SS set according to some embodiments of the present disclosure. As shown in FIG. 6, assuming that N1 is shown and n1 = 0, n2 = 0, n3 = 1, and n4 are all shown, the time resource 600 may be determined within subframe 1 of frame 0.

[0164] In some exemplary embodiments, the SFN for transmitting the LP-SS may be preset or pre-indicated. In some examples, the LP-SS set may be transmitted in at least one predetermined system frame (e.g., SFN 0 or 1) regardless of which cell it is transmitted in. In this way, the terminal device 120 can assume that the LP-SS is always transmitted in a predetermined system frame, which is beneficial for detecting unknown LP-SS.

[0165] Alternatively, or in addition, a set of OFDM symbols within a subframe or slot may also be shown to the terminal device 120, and the LP-SS may occupy a time resource that overlaps with the set of OFDM symbols.

[0166] In this way, the terminal device 120 may acquire or maintain the HFN, SFN, subframe index, slot index, and / or OFDM symbol index based on the detection timing of the LP-SS.

[0167] Since it is a hyperframe with a period of N1, there is at most one LP-SS set in one hyperframe, and it should be understood that the terminal device 120 does not need to distinguish different LP-SS sets. In some embodiments, the LP-SS sets may be the same as each other. For example, there is a first LP-SS set including N LP-SSs and a second LP-SS set including N LP-SSs, and the i-th LP-SS in the first LP-SS set is the same as the i-th LP-SS in the second LP-SS set, where i is an integer from 0 to N. In this way, the complexity at the terminal device 120 can be reduced, and the power consumption can also be reduced.

[0168] In some exemplary embodiments, the period may be equal to a plurality of frames. For example, the period may be M frames, and M may be an integer from 0 to 1023. In other words, the period may be shorter than the hyperframe.

[0169] In some embodiments, at least one of the frame offset m1, subframe offset m2, and slot offset m3 may also be indicated to the terminal device 120.

[0170] In some examples, the period M and the frame offset m1 are indicated, and the LP-SS set may be transmitted in the system frame of SFN m0, where (m0 mod M) = m1. In some examples, the terminal device 120 may assume that the LP-SS set appears in any subframe or slot within the system frame m0.

[0171] In some examples, the subframe offset m2 is also indicated, and the LP-SS set may be transmitted in the subframe with index m2 within the frame of SFN m0.

[0172] In some examples, a slot offset m3 is also shown, and the LP-SS set may be transmitted in the slot of index m3 in the subframe of index m2 within the frame of SFN m0.

[0173] Alternatively, or in addition, a set of OFDM symbols within a subframe or slot can also be shown for the terminal device 120, and the LP-SS may occupy time resources overlapping with the set of OFDM symbols.

[0174] It should be understood that since the period is shorter than the hyperframe, there is one or more LP-SS sets in the hyperframe. In some embodiments, different LP-SS sets within the hyperframe may be associated with different indices, and thus, the set of time resources for the LP-SS may be determined based on the index of the LP-SS group (or LP-SS set).

[0175] FIG. 7 shows a schematic diagram of different LP-SS sets 700 according to some embodiments of the present disclosure. As shown in FIG. 7, within the hyperframe 710, the first LP-SS set 712 is in the frame of SFNi, and the second LP-SS set 714 is in the frame of SFNi+M.

[0176] Assuming there are T LP-SS sets (e.g., T = 1024 / M) in the hyperframe, in order for the terminal device 120 to be able to determine the SFN number, the LP-SSs within different LP-SS sets should be different. For example, among the T LP-SS sets, the i-th LP-SS in the first LP-SS set is different from the i-th LP-SS in the second LP-SS set, where i is an integer. In some examples, the sequence of the LP-SS may be generated based on the index of the LP-SS set in the T LP-SS sets.

[0177] In this way, the terminal device 120 may acquire the SFN, subframe index, slot index, and / or OFDM symbol index based on the detection timing of the LP-SS.

[0178] In some examples, the m-sequence (shown in Equation (1)) for generating the LP-SS may also be associated with the index of the LP-SS set in the T LP-SS sets. For example,

Number

Number

[0179] In some examples, the one shown in Equation (1)

Number

[0180] In this way, the terminal device 120 can achieve and maintain time synchronization with the network device 110 with a certain accuracy. Moreover, the terminal device 120 can further acquire and maintain the SFN. In this case, after waking up from the LP mode, the terminal device 120 can quickly determine the timing of SSB measurement and paging monitoring. It should be understood that compared with the SSB, since OOK detection is more robust to time errors, the LP-SS does not need to provide very accurate time-domain synchronization. Therefore, compared with the SSB, the time-domain setting of the LP-SS can be simplified in design.

[0181] This disclosure can provide an acceptable accuracy of time synchronization based on the LP-SS, and in the terminal device 120, low complexity and low overhead can be maintained.

[0182] In some exemplary embodiments, the terminal device 120 may always detect (or monitor) the wake-up signal by using, for example, synchronization based on the received LP-SS. In some other embodiments, in order to reduce power consumption, it is not necessary for the terminal device 120 to always monitor the wake-up signal.

[0183] In some exemplary embodiments, an LP-WUS monitor window (abbreviated as window) may be set in the terminal device 120. In some examples, the network device of the serving cell (network device 110 or another network device) may send an instruction of the window to the terminal device 120. Then, the terminal device 120 may monitor only the LP-WUS within the window.

[0184] In some embodiments, the length of the monitor window may be set in the terminal device 120, and the length can be one or more system frames, sub-frames, slots, or milliseconds.

[0185] In some embodiments, an offset of the LP-WUS monitor window can also be set in the terminal device 120, and the offset indicates a time offset from the LP-SS and the LP-WUS monitor window.

[0186] For better understanding, reference is now made to FIG. 8. FIG. 8 shows a schematic diagram of a time window 800 of LP-WUS according to some embodiments of the present disclosure. As shown in FIG. 8, the start point 810 of the window may be determined based on the window offset 801 from the LP-SS 802. Also, the window 820 for monitoring LP-WUS may be determined based on the start point 810 and the length (nn frames shown in FIG. 8).

[0187] In some exemplary embodiments, the terminal device 120 may also be set with a period of the LP-WUS monitoring window, which indicates the period between two adjacent LP-WUS monitoring windows. To facilitate understanding, reference is made here to FIG. 9. FIG. 9 shows a schematic diagram of a time window 900 of LP-WUS according to some embodiments of the present disclosure. As shown in FIG. 9, a first window 910 is shown, and a second window 920 following the first window 910 may be determined based on a period 930 of the LP-WUS monitor window. For example, the period between the start point 904 of window 920 and the start point 902 of window 910 is indicated by period 930.

[0188] In some exemplary embodiments, there may be multiple opportunities within the window, and each opportunity is associated with an LP-SS within the LP-SS set. In some examples, there may be N LP-SS signals in the LP-SS set, there may be N opportunities in the window, and the i-th opportunity may be associated with the i-th LP-SS signal. Here, N is an integer, and i is an integer from 0 to N. As described above, the N LP-SS signals may be associated with N TX beams, or may be quasi-collocated with N SSBs. And the terminal device 120 may assume that the LP-WUS is transmitted in the same beam as the associated LP-SS, or that the LP-WUS is quasi-collocated with the associated LP-SS, or that the LP-WUS and the associated LP-SS are quasi-collocated with the same SSB or CSI-RS resource.

[0189] In some examples, one opportunity within the window may be set. For example, one opportunity may be indicated by a start time and / or a duration. In some examples, the duration of the opportunity may be less than one frame.

[0190] In some exemplary embodiments, the terminal device 120 may detect a blink of the LP-WUS within the window. In other words, the terminal device 120 may assume that the LP-WUS may appear at any opportunity within the window.

[0191] According to the embodiments described with reference to FIGS. 3 to 8, time synchronization with the network side with a certain accuracy can be maintained based on the LP-SS, and the performance of detecting the LP-WUS can be enhanced. In this way, efficiency can be improved and overhead can be reduced.

[0192] Further referring to FIG. 10. FIG. 10 shows a signaling chart showing a communication process 1000 according to some exemplary embodiments of the present disclosure. For the purpose of discussion only, the process 1000 will be described with reference to FIG. 1. The process 1000 may involve the terminal device 120 and the network device 110 (for example, the network device 110-1 or the network device 110-2).

[0193] The network device 110 generates (1010) an LP synchronization signal (LP-SS). In some embodiments, the LP-SS is different from the PSS or SSS. It should be understood that the description regarding operation 310 when referring to FIG. 3 can be applied to operation 1010 in FIG. 10, and similar disclosure content will not be repeated here.

[0194] The network device 110 transmits (1020) the LP-SS 1022 to the terminal device 120.

[0195] The terminal device 120 detects (1023) the LP-SS, or the terminal device 120 receives (1024) the LP-SS 1022. The terminal device 120 determines (1030) the state of the terminal device 120 with respect to the coverage of the LP-SS. The terminal device 120 determines (1040) whether to wake up from the LP mode or report to the network device 110 based on the state of the terminal device 120.

[0196] In some exemplary embodiments, the terminal device 120 may determine that it is outside the coverage of the LP-SS based on at least one of the following: it was unable to receive the LP-SS during a predetermined duration; it was unable to receive the LP-SS during a predetermined number of consecutive LP-SS monitoring opportunities; the number of LP-SSs received normally during a predetermined duration is less than a threshold number; the number of LP-SSs received normally during a predetermined number of consecutive LP-SS monitoring opportunities is less than a threshold number; the received signal strength of the LP-SS is less than a threshold strength; the power ratio between the on symbol and the off symbol in the LP-SS is less than a threshold ratio; the signal-to-noise ratio (SNR) of the LP-SS is less than a threshold SNR; or it received another LP-SS different from the said LP-SS.

[0197] In some embodiments, the terminal device 120 may determine its position.

[0198] For better understanding, reference is now made to FIG. 11. FIG. 11 shows an exemplary scenario 1100 according to some embodiments of the present disclosure. As shown in FIG. 11, the coverage 1110 of the LP-SS is smaller than the coverage 1120 of the normal physical channel.

[0199] Generally, the distance between sites is planned based on the coverage of normal physical channels such as, for example, the physical broadcast channel (PBCH), the physical random access channel (PRACH), the PDCCH, the PUCCH, etc. However, since OOK modulation is used, the coverage of the LP signal may be inferior to that of normal physical channels. Therefore, when the terminal device 120 moves into the coverage hole of the LP signal (e.g., outside the coverage 1010 in FIG. 10), it may not be able to receive the LP signal, and thus the terminal device 120 may need to recognize the situation of being outside the coverage.

[0200] In the present disclosure, the LP-SS may be used to assist the terminal device 120 in determining whether it is outside the coverage of the LP-SS.

[0201] In some exemplary embodiments, a predetermined duration may be represented as T0, and a predetermined number of consecutive LP-SS monitoring windows / opportunities may be represented as N2. If the terminal device 120 cannot receive the LP-SS within T0 or in N2 consecutive LP-SS monitoring windows / opportunities, the terminal device 120 may determine that it is outside the coverage of the LP-SS. For example, T0 is equal to a plurality of milliseconds or subframes, and N2 is an integer greater than 0.

[0202] In some exemplary embodiments, the predetermined duration may be represented as T01, the predetermined number of consecutive LP-SS monitoring windows / opportunities may be represented as N21, and the threshold number may be represented as N22. If the terminal device 120 normally receives N20 LP-SS within T01 or in N21 consecutive LP-SS monitoring windows / opportunities, and N20 < N22, the terminal device 120 may determine that it is outside the coverage of the LP-SS. For example, T01 is equal to a plurality of milliseconds or subframes, and N22 is an integer greater than 0. For example, T01 = T0 and N21 = N2. It should be noted that the received N20 LP-SS do not need to be consecutive.

[0203] In some exemplary embodiments, the terminal device 120 may measure the signal quality of the LP-SS and determine whether it is outside the coverage of the LP-SS based on the measurement result. In some exemplary embodiments, the measurement result may be at least one of a received signal strength indicator (RSSI), a power ratio, or an SNR.

[0204] In some embodiments, the RSSI may be the RSSI of LP-SS or LP-WUS. For example, the RSSI may be measured based on the signal strength of the OOK on-symbol in the LP signal (such as LP-SS). In some examples, the OOK off-symbol in the LP signal is not considered in the RSSI.

[0205] In some embodiments, the power ratio between the OOK on-symbol and the OOK off-symbol in the LP signal (such as LP-SS) is determined based on the ratio between the average power of the OOK on-symbol and the average power of the OOK off-symbol. For example, the average power of the OOK on-symbol may indicate the average value of the power of the OOK on-symbols in the OOK sequence. For example, the average power of the OOK off-symbol may indicate the average value of the power of the OOK off-symbols in the OOK sequence. In some examples, the average power may be filtered or averaged among multiple OOK sequences. In some examples, the average power can also be referred to as average energy / amplitude / intensity.

[0206] In some embodiments, the SNR is determined based on the ratio between the average power of the OOK symbol and the noise power, and the OOK symbol may include only the OOK on-symbol, or may include the OOK on-symbol and the off-symbol.

[0207] In some exemplary embodiments, when the terminal device 120 is in the LP mode and determines that it is outside the coverage of the LP-SS, the terminal device 120 may wake up from the LP mode. In some embodiments, the terminal device 120 may further send a report to the network device 110, and the report may indicate the above-described measurement results.

[0208] In some examples, the terminal device 120 may stop monitoring the LP signal and enter the normal operation in the RRC idle / inactive state. For example, the terminal device 120 may be in the main mode. In some examples, the terminal device 120 may select a cell and start monitoring the paging message in the cell. For example, the terminal device 120 may monitor the paging opportunity based on the paging setting.

[0209] Alternatively, the terminal device 120 may start the initial access procedure after waking up from the LP mode. In some embodiments, if the cell selected by the terminal device 120 after waking up from the LP mode has a different TAC from the cell before entering the LP mode, the terminal device 120 may start the initial access procedure. In some embodiments, if the cell selected by the terminal device 120 after waking up from the LP mode has the same TAC as the cell before entering the LP mode, since it is not necessary for the terminal device 120 to start the initial access procedure, the communication efficiency can be improved.

[0210] In this way, since the terminal device 120 can determine whether it is out of coverage, the terminal device 120 can wake up in time when it is out of coverage.

[0211] In some further exemplary embodiments, the terminal device 120 may move from the first cell to the second cell, the LP-SS of the first cell is associated with the first ID, and the LP-SS of the second cell is associated with a second ID different from the first ID. Here, refer to FIG. 12. FIG. 12 shows an exemplary scenario 1200 according to some embodiments of the present disclosure. As shown in FIG. 12, the terminal device 120 may move from the cell 1210 to the cell 1220, and the cell 1210 and the cell 1220 have different LP-SS settings.

[0212] In some examples, the terminal device 120 may move from the cell / cell group of LP-SS setting 1 to the cell / cell group of LP-SS setting 2. In this case, since the network device 110 is unaware that the terminal device 120 has moved to a new area, the terminal device 120 may wake up and execute the initial access procedure, and may need to notify the network of its new location. Subsequently, the network may page the terminal device 120 within the new cell or cell group.

[0213] In some embodiments, the terminal device 120 may receive a different LP-SS (also referred to as a new LP-SS) from the previous LP-SS, and the terminal device 120 may determine that it has moved to an area with a different LP-SS setting. Referring to FIG. 12, the terminal device 120 moves from cell 1210 to cell 1220, and the terminal device 120 may receive an LP-SS from cell 1220, and the received new LP-SS is different from the previous LP-SS from cell 1210.

[0214] In some examples, the terminal device 120 may wake up from the LP mode, perform a cell search, and initiate an initial access procedure to a cell with a new LP-SS setting, such as cell 1220 in FIG. 12.

[0215] In some embodiments, the terminal device 120 may determine that it has moved to an area with a different LP-SS setting based on at least one of the following: the terminal device 120 was unable to detect the previous LP-SS during a preset duration, the terminal device 120 determined that it was outside the coverage of the previous LP-SS, or the received new LP-SS is determined to have better quality than the previous LP-SS. The quality can be obtained by any of RSSI, power ratio, SNR, average power, etc., but it should be understood that the present disclosure is not limited in this regard.

[0216] In some other embodiments, the terminal device 120 may determine whether to wake up according to its specific implementation (UE implementation) based on the detected one or more LP-SSs. Here, the one or more LP-SSs may or may not include previously set LP-SSs.

[0217] According to the above description, the terminal device 120 in the LP mode can receive LP signals, and thus can maintain synchronization with a certain accuracy and enhance the detection performance. Further, the terminal device 120 can determine whether it is outside the coverage of the LP-SS or has moved to a new area, and can send a report to the network device 110. As a result, the network can recognize the state of the terminal device 120.

[0218] In some embodiments of the present disclosure, the LP-SS may be used even when the terminal device 120 is not in the LP mode.

[0219] In some embodiments, the terminal device 120 may be in the RRC connection mode. When the terminal device 120 is set to measure the LP-SS, the terminal device 120 may measure the detected LP-SS and send a report to the network device 110. In some examples, the report may include at least one measurement result based on the LP-SS and / or assistance information for setting the LP mode or the LP-SS. In this way, the network device 110 may receive the report, and the report may assist the network device 110 in determining whether to set the terminal device 120 to enter the LP mode.

[0220] In some embodiments, the terminal device 120 may be in the RRC idle mode or the inactive mode. The terminal device 120 may measure the detected LP-SS (alternatively, the terminal device 120 may be configured to measure the LP-SS) and determine whether it is outside the coverage of the LP-SS. In some examples, when the terminal device 120 is within the coverage of the LP-SS, the terminal device 120 may initiate an initial access procedure. Also, the terminal device 120 may send a report to the network device 110. In some examples, the report may include at least one measurement result based on the LP-SS and / or assistance information for setting the LP mode or the LP-SS. In some examples, the report may be included in message 3 or message A sent during the initial access procedure. Thus, the network device 110 may receive the report, and the report may assist the network device 110 in determining whether to configure the terminal device 120 to enter the LP mode.

[0221] FIG. 13 shows a flowchart of an exemplary method 1300 implemented by a terminal device according to some embodiments of the present disclosure. For the purpose of discussion, method 1300 will be described from the perspective of the terminal device 120 with reference to FIG. 1.

[0222] In block 1310, the terminal device 120 in the LP mode receives a LP synchronization signal from the network device 110 based on at least one of the ID of the cell group of the network device 110, the ID of the LP-SS group of the network device 110, the tracking area ID associated with the network device 110, or the tracking area code associated with the network device 110. In block 1320, the terminal device 120 detects a wake-up signal from the network device 110 based on the LP synchronization signal.

[0223] In some exemplary embodiments, the LP synchronization signal includes an amplitude modulation sequence.

[0224] In some exemplary embodiments, the amplitude modulation sequence includes at least one OOK on symbol and at least one OOK off symbol.

[0225] In some exemplary embodiments, the LP synchronization signal is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of the network device 110 or are quasi-collocated with a plurality of SSBs transmitted by the network device 110.

[0226] In some exemplary embodiments, the plurality of signals are based on a common amplitude modulation sequence and are transmitted on different time resources.

[0227] In some exemplary embodiments, the plurality of signals are based on different amplitude modulation sequences, and each of the plurality of signals is associated with at least one of a subframe index, a slot index, or an index of the plurality of signals.

[0228] In some exemplary embodiments, the wake-up signal notifies the terminal device 120 of at least one of staying in the LP mode, waking up from the LP mode, or the settings of the LP synchronization signal transmitted by the network device 110.

[0229] In some exemplary embodiments, the terminal device 120 determines a set of time resources for receiving the LP synchronization signal based on at least one of the HFN, the transmission period of the LP synchronization signal, the hyperframe offset, the frame offset, the subframe offset, or the slot offset.

[0230] In some exemplary embodiments, the terminal device 120 receives an indication of an initial HFN in the serving cell before entering the LP mode and determines the HFN based on the initial HFN.

[0231] In some exemplary embodiments, the indication of the initial HFN is sent by one of system information, RRC signaling, or PDCP parameters.

[0232] In some exemplary embodiments, the terminal device 120 determines an initial HFN based on the time when the terminal device 120 receives control information indicating that the terminal device 120 enters the LP mode, and determines the HFN based on the initial HFN.

[0233] In some exemplary embodiments, the transmission period is equal to a plurality of hyperframes.

[0234] In some exemplary embodiments, the transmission period is equal to a plurality of frames, and the set of time resources is further determined based on the ID of the LP-SS group including the LP synchronization signal.

[0235] In some exemplary embodiments, the terminal device 120 detecting a wake-up signal includes detecting the wake-up signal at one of a plurality of opportunities within the time window indicated by the network device 110.

[0236] In some exemplary embodiments, the wake-up signal at one of the plurality of opportunities is associated with the LP synchronization signal among the plurality of signals, and the rank of one of the plurality of opportunities among the plurality of opportunities is the same as the rank of the LP synchronization signal among the plurality of signals.

[0237] In some exemplary embodiments, the terminal device 120 enters the LP mode by turning off the main mode. Here, the terminal device 120 in the main mode performs at least one of paging monitoring, cell selection or reselection, measurement based on the primary synchronization signal (PSS), secondary synchronization signal (SSS), or channel state information-reference signal (CSI-RS), physical downlink control channel (PDCCH) monitoring, or uplink transmission.

[0238] In some exemplary embodiments, the LP synchronization signal is different from the PSS or SSS received in the main mode.

[0239] FIG. 14 shows a flowchart of an exemplary method 1400 implemented in a terminal device according to some embodiments of the present disclosure. For the purpose of discussion, method 1400 will be described from the perspective of the terminal device 120 with reference to FIG. 1.

[0240] In block 1410, the terminal device 120 detects an LP synchronization signal from the network device 110. In block 1420, the terminal device 120 determines the state of the terminal device 120 with respect to the coverage of the LP synchronization signal based on the detection of the LP synchronization signal. In block 1430, the terminal device 120 determines whether to wake up from the LP mode or report the state to the network device 110 based on the state.

[0241] In some exemplary embodiments, the terminal device 120 determining the state of the terminal device 120 includes determining that the terminal device 120 is out of coverage based on at least one of: not being able to receive the LP synchronization signal during a predetermined duration, not being able to receive the LP synchronization signal during a predetermined number of consecutive LP synchronization signal monitoring opportunities, the number of LP synchronization signals normally received during a predetermined duration being less than a threshold number, the number of LP synchronization signals normally received during a predetermined number of consecutive LP synchronization signal monitoring opportunities being less than a threshold number, the received signal strength of the LP synchronization signal being less than a threshold strength, the power ratio between the on symbol and the off symbol in the LP synchronization signal being less than a threshold ratio, the signal-to-noise ratio (SNR) of the LP synchronization signal being less than a threshold SNR, or receiving another LP synchronization signal different from the LP synchronization signal.

[0242] In some exemplary embodiments, in accordance with the determination that the terminal device 120 is out of coverage and in the LP mode, the terminal device 120 wakes up from the LP mode.

[0243] In some exemplary embodiments, in accordance with the determination that the terminal device 120 wakes up from the LP mode, the terminal device 120 selects a cell and monitors paging messages in the cell.

[0244] In some exemplary embodiments, in accordance with the determination that the terminal device 120 wakes up from the LP mode, the terminal device 120 selects a cell, and in accordance with the determination that the first tracking area code associated with the selected cell is different from the second tracking area code associated with the initial cell before the terminal device 120 enters the LP mode, the terminal device 120 starts an initial access procedure.

[0245] In some exemplary embodiments, in accordance with the determination that the terminal device 120 is set to measure the detected LP synchronization signal and is in the RRC connected mode, the terminal device 120 transmits a report to the network device 110. The report includes at least one of measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal.

[0246] In some exemplary embodiments, in accordance with the determination that the terminal device 120 is within coverage and is in the RRC idle mode or the inactive mode, the terminal device 120 starts an initial access procedure.

[0247] In some exemplary embodiments, the terminal device 120 transmits a report including at least one of measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal to the network device 110.

[0248] In some exemplary embodiments, the report is included in message 3 or message A transmitted during the initial access procedure.

[0249] Figure 15 shows a flowchart of an exemplary method 1500 implemented by a network device according to some embodiments of the present disclosure. For purposes of discussion, method 1500 will be described from the perspective of network device 110 with reference to FIG. 1.

[0250] In block 1510, network device 110 generates an LP synchronization signal based on at least one of the ID of the cell group of network device 110, the ID of the LP-SS group of network device 110, the tracking area ID associated with network device 110, or the tracking area code associated with network device 110. In block 1520, network device 110 transmits the LP synchronization signal to terminal device 120 in LP mode.

[0251] In some exemplary embodiments, the LP synchronization signal includes an amplitude modulation sequence.

[0252] In some exemplary embodiments, the amplitude modulation sequence includes at least one OOK on symbol and at least one OOK off symbol.

[0253] In some exemplary embodiments, the LP synchronization signal is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of network device 110 or are quasi-collocated with a plurality of SSBs transmitted by network device 110.

[0254] In some exemplary embodiments, the plurality of signals are based on a common amplitude modulation sequence and are transmitted in different time resources.

[0255] In some exemplary embodiments, the plurality of signals are based on different amplitude modulation sequences, and each of the plurality of signals is associated with at least one of a subframe index, a slot index, or an index of the plurality of signals.

[0256] In some exemplary embodiments, the network device 110 transmits a wake-up signal. The wake-up signal notifies the terminal device 120 of at least one of staying in the LP mode, waking up from the LP mode, or setting the LP synchronization signal transmitted by the network device 110.

[0257] In some exemplary embodiments, the network device 110 transmitting the wake-up signal includes transmitting the wake-up signal at one of a plurality of opportunities within a time window.

[0258] In some exemplary embodiments, the wake-up signal at one of the plurality of opportunities is associated with the LP synchronization signal among the plurality of signals, and the rank of one of the plurality of opportunities among the plurality of opportunities is the same as the rank of the LP synchronization signal among the plurality of signals.

[0259] In some exemplary embodiments, the network device 110 transmits an indication of an initial HFN to the terminal device 120 in the main mode.

[0260] In some exemplary embodiments, the indication of the initial HFN is transmitted by one of system information, radio resource control (RRC) signaling, or packet data convergence protocol (PDCP) parameters.

[0261] In some exemplary embodiments, the transmission period of the LP synchronization signal is equal to a plurality of hyperframes or a plurality of frames.

[0262] In some exemplary embodiments, the network device 110 receives a report from the terminal device 120 that includes at least one of measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal.

[0263] In some exemplary embodiments, the report is included in Message 3 or Message A transmitted during the initial access procedure initiated by the terminal device 120.

[0264] In some exemplary embodiments, the LP synchronization signal is different from the PSS or SSS received in the main mode.

[0265] Details of some embodiments according to the present disclosure have been described with reference to FIGS. 1 to 15. Next, exemplary implementations of the terminal device and the network device will be discussed below.

[0266] In some exemplary embodiments, the terminal device includes a circuit configured to receive, in the LP mode, an LP synchronization signal based on at least one of the ID of the cell group of the network device, the ID of the LP-SS group of the network device, the tracking area ID associated with the network device, or the tracking area code associated with the network device, and to detect a wake-up signal from the network device based on the LP synchronization signal.

[0267] In some exemplary embodiments, the LP synchronization signal includes an amplitude modulation sequence.

[0268] In some exemplary embodiments, the amplitude modulation sequence includes at least one OOK on-symbol and at least one OOK off-symbol.

[0269] In some exemplary embodiments, the LP synchronization signal is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of the network device or are quasi-collocated with a plurality of SSBs transmitted by the network device.

[0270] In some exemplary embodiments, the plurality of signals are based on a common amplitude modulation sequence and are transmitted in different time resources.

[0271] In some exemplary embodiments, the plurality of signals are based on different amplitude modulation sequences, and each of the plurality of signals is associated with at least one of a subframe index, a slot index, or an index of the plurality of signals.

[0272] In some exemplary embodiments, the wake-up signal notifies the terminal device of at least one of staying in the LP mode, waking up from the LP mode, or settings of the LP synchronization signal transmitted by the network device.

[0273] In some exemplary embodiments, the terminal device includes a circuit configured to determine a set of time resources for receiving the LP synchronization signal based on at least one of an HFN, a transmission period of the LP synchronization signal, a hyperframe offset, a frame offset, a subframe offset, or a slot offset.

[0274] In some exemplary embodiments, the terminal device includes a circuit configured to receive an indication of an initial HFN in a serving cell and determine the HFN based on the initial HFN before entering the LP mode.

[0275] In some exemplary embodiments, the indication of the initial HFN is transmitted by one of system information, RRC signaling, or PDCP parameters.

[0276] In some exemplary embodiments, the terminal device includes a circuit configured to determine the initial HFN based on the time when the terminal device receives control information indicating that the terminal device is to enter the LP mode, and determine the HFN based on the initial HFN.

[0277] In some exemplary embodiments, the transmission period is equal to a plurality of hyperframes.

[0278] In some exemplary embodiments, the transmission period is equal to a plurality of frames, and the set of time resources is further determined based on the ID of the LP-SS group including the LP synchronization signal.

[0279] In some exemplary embodiments, the terminal device includes a circuit configured to detect a wake-up signal at one of a plurality of opportunities within a time window indicated by the network device.

[0280] In some exemplary embodiments, the wake-up signal at one of the plurality of opportunities is associated with the LP synchronization signal among the plurality of signals, and the rank of one of the plurality of opportunities among the plurality of opportunities is the same as the rank of the LP synchronization signal among the plurality of signals.

[0281] In some exemplary embodiments, the terminal device includes a circuit configured to enter the LP mode by turning off the main mode. Here, the terminal device in the main mode performs at least one of paging monitoring, cell selection or reselection, measurement based on a primary synchronization signal (PSS), a secondary synchronization signal (SSS), or a channel state information-reference signal (CSI-RS), physical downlink control channel (PDCCH) monitoring, or uplink transmission.

[0282] In some exemplary embodiments, the LP synchronization signal is different from the PSS or SSS received in the main mode.

[0283] In some exemplary embodiments, the terminal device includes a circuit configured to detect an LP synchronization signal from the network device, determine the state of the terminal device with respect to the coverage of the LP synchronization signal based on the detection of the LP synchronization signal, and determine whether to wake up from the LP mode or report the state to the network device based on the state.

[0284] In some exemplary embodiments, the terminal device includes a circuit configured to determine that the terminal device is out of coverage based on at least one of: the terminal device being unable to receive an LP synchronization signal during a predetermined duration; the terminal device being unable to receive an LP synchronization signal during a predetermined number of consecutive LP synchronization signal monitoring opportunities; the number of LP synchronization signals received normally during a predetermined duration being less than a threshold number; the number of LP synchronization signals received normally during a predetermined number of consecutive LP synchronization signal monitoring opportunities being less than a threshold number; the received signal strength of the LP synchronization signal being less than a threshold strength; the power ratio between the on symbol and the off symbol in the LP synchronization signal being less than a threshold ratio; the signal-to-noise ratio (SNR) of the LP synchronization signal being less than a threshold SNR; or the terminal device receiving another LP synchronization signal different from the LP synchronization signal.

[0285] In some exemplary embodiments, the terminal device includes a circuit configured to wake up from the LP mode according to a determination that the terminal device is out of coverage and in the LP mode.

[0286] In some exemplary embodiments, the terminal device includes a circuit configured to select a cell according to a determination that the terminal device wakes up from the LP mode and monitor a paging message in the cell.

[0287] In some exemplary embodiments, the terminal device includes a circuit configured to start an initial access procedure according to a determination that the terminal device wakes up from the LP mode, selects a cell, and the first tracking area code associated with the selected cell is different from the second tracking area code associated with the initial cell before the terminal device enters the LP mode.

[0288] In some exemplary embodiments, the terminal device includes a circuit configured to measure the LP synchronization signal detected by the terminal device and to transmit a report to the network device according to a determination that the terminal device is in the RRC connected mode. The report includes at least one of the measurement results based on the LP synchronization signal, or the assistance information for setting the LP mode or the LP synchronization signal.

[0289] In some exemplary embodiments, the terminal device includes a circuit configured to start an initial access procedure according to a determination that the terminal device is within coverage and in the RRC idle mode or the inactive mode.

[0290] In some exemplary embodiments, the terminal device includes a circuit configured to transmit a report including at least one of the measurement results based on the LP synchronization signal, or the assistance information for setting the LP mode or the LP synchronization signal, to the network device.

[0291] In some exemplary embodiments, the report is included in message 3 or message A transmitted during the initial access procedure.

[0292] In some exemplary embodiments, the network device includes a circuit configured to generate an LP synchronization signal based on at least one of the ID of the cell group of the network device, the ID of the LP-SS group of the network device, the tracking area ID associated with the network device, or the tracking area code associated with the network device, and to transmit the LP synchronization signal to the terminal device in the LP mode.

[0293] In some exemplary embodiments, the LP synchronization signal includes an amplitude modulation sequence.

[0294] In some exemplary embodiments, the amplitude modulation sequence includes at least one OOK on symbol and at least one OOK off symbol.

[0295] In some exemplary embodiments, the LP synchronization signal is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of a network device or are quasi - co - located with a plurality of SSBs transmitted by the network device.

[0296] In some exemplary embodiments, the plurality of signals are based on a common amplitude modulation sequence and are transmitted at different time resources.

[0297] In some exemplary embodiments, the plurality of signals are based on different amplitude modulation sequences, and each of the plurality of signals is associated with at least one of a sub - frame index, a slot index, or an index of the plurality of signals.

[0298] In some exemplary embodiments, the network device includes a circuit configured to transmit a wake - up signal. The wake - up signal notifies the terminal device of at least one of staying in the LP mode, waking up from the LP mode, or the setting of the LP synchronization signal transmitted by the network device.

[0299] In some exemplary embodiments, the network device includes a circuit configured to transmit a wake - up signal at one of a plurality of opportunities within a time window.

[0300] In some exemplary embodiments, the wake - up signal at one of the plurality of opportunities is associated with the LP synchronization signal among the plurality of signals, and the rank of one of the plurality of opportunities among the plurality of opportunities is the same as the rank of the LP synchronization signal among the plurality of signals.

[0301] In some exemplary embodiments, the network device includes a circuit configured to transmit an indication of an initial HFN to a terminal device in the main mode.

[0302] In some exemplary embodiments, the indication of the initial HFN is transmitted by one of system information, radio resource control (RRC) signaling, or packet data convergence protocol (PDCP) parameters.

[0303] In some exemplary embodiments, the transmission period of the LP synchronization signal is equal to a plurality of hyperframes or a plurality of frames.

[0304] In some exemplary embodiments, the network device includes a circuit configured to receive from the terminal device a report including at least one of measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal.

[0305] In some exemplary embodiments, the report is included in message 3 or message A transmitted during an initial access procedure initiated by the terminal device.

[0306] In some exemplary embodiments, the LP synchronization signal is different from the PSS or SSS received in the main mode.

[0307] FIG. 16 shows a schematic block diagram of an apparatus 1600 suitable for implementing an embodiment of the present disclosure. The apparatus 1600 can be considered a further exemplary implementation of the terminal device 120 and the network device 110 shown in FIG. 1. Therefore, the apparatus 1600 can be implemented in or at least as part of the terminal device 120 or the network device 110.

[0308] As shown in the figure, apparatus 1600 includes a processor 1610, a memory 1620 coupled to the processor 1610, a suitable transmitter (TX) and receiver (RX) 1640 coupled to the processor 1610, and a communication interface coupled to the TX / RX 1640. The memory 1610 stores at least a part of program 1630. The TX / RX 1640 is for bidirectional communication. The TX / RX 1640 has at least one antenna for facilitating communication, but in practice, the access nodes described in this disclosure may have multiple antennas. The communication interface may represent any interface necessary for communicating with other network elements, for example, the X2 interface for bidirectional communication between eNBs, the S1 interface for communication between a Mobility Management Entity (MME) / Serving Gateway (S-GW) and an eNB, the Un interface for communication between an eNB and a relay node (RN), or the Uu interface for communication between an eNB and a terminal device.

[0309] Program 1630 is assumed to include program instructions, and when the program is executed by the associated processor 1610, it enables apparatus 1600 to operate in accordance with the embodiments of this disclosure as discussed with reference to FIGS. 2 - 10 herein. The embodiments herein may be implemented by computer software, hardware, or a combination of software and hardware executable by the processor 1610 of apparatus 1600. The processor 1610 may be configured to implement various embodiments of this disclosure. Also, the combination of the processor 1610 and the memory 1620 may constitute processing means 1650 suitable for implementing various embodiments of this disclosure.

[0310] Memory 1620 may be of any type suitable for a local technical network and may be implemented by any suitable data storage technology (examples include, but are not limited to, computer-readable non-transitory storage media, semiconductor-based storage devices, magnetic storage devices and systems, optical storage devices and systems, fixed memory, and removable memory, etc.). Although only one memory 1620 is shown in device 1600, a plurality of physically different memory modules may be installed in device 1600. Processor 1610 may be of any type suitable for a local technical network and may include, for example, but is not limited to, a general-purpose computer, a dedicated computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor configuration, one or more of which may be included. Device 1600 may have a plurality of processors, for example, application-specific integrated circuit chips that are temporally dependent on a clock synchronized with the main processor.

[0311] In summary, embodiments of the present disclosure can provide the following solutions.

[0312] The present disclosure provides a communication method. The communication method includes receiving, in a terminal device in a low-power (LP) mode, an LP synchronization signal from a network device based on at least one of an identity (ID) of a cell group of the network device, an ID of an LP-SS group of the network device, a tracking area ID associated with the network device, or a tracking area code associated with the network device, and detecting a wake-up signal from the network device based on the LP synchronization signal.

[0313] In one embodiment, in the above method, the LP synchronization signal includes an amplitude modulation sequence.

[0314] In one embodiment, in the above method, the amplitude modulation sequence includes at least one on-off keying (OOK) on symbol and at least one OOK off symbol.

[0315] In one embodiment, in the above method, the LP synchronization signal is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of a network device or quasi - co - located (QCL) with a plurality of synchronization signal blocks (SSBs) transmitted by the network device.

[0316] In one embodiment, in the above method, the plurality of signals are based on a common amplitude modulation sequence and are transmitted in different time resources.

[0317] In one embodiment, in the above method, the plurality of signals are based on different amplitude modulation sequences, and each of the plurality of signals is associated with at least one of a sub - frame index, a slot index, or an index of the plurality of signals.

[0318] In one embodiment, in the above method, the wake - up signal notifies the terminal device of at least one of staying in the LP mode, waking up from the LP mode, or the setting of the LP synchronization signal transmitted by the network device.

[0319] In one embodiment, the above method further includes determining a set of time resources for receiving the LP synchronization signal based on at least one of a hyper - frame number (HFN), a transmission period of the LP synchronization signal, a hyper - frame offset, a frame offset, a sub - frame offset, or a slot offset.

[0320] In one embodiment, the above method further includes receiving an indication of an initial HFN in a serving cell before entering the LP mode and determining the HFN based on the initial HFN.

[0321] In one embodiment, in the above method, the indication of the initial HFN is transmitted by one of system information, radio resource control (RRC) signaling, or packet data convergence protocol (PDCP) parameters.

[0322] In one embodiment, the method further includes determining an initial HFN based on the time when the terminal device receives control information indicating to enter the LP mode, and determining the HFN based on the initial HFN.

[0323] In one embodiment, in the above method, the transmission period is equal to a plurality of hyperframes.

[0324] In one embodiment, in the above method, the transmission period is equal to a plurality of frames, and the set of time resources is further determined based on the ID of the LP-SS group including the LP synchronization signal.

[0325] In one embodiment, in the above method, detecting the wake-up signal includes detecting the wake-up signal at one of a plurality of opportunities within the time window indicated by the network device.

[0326] In one embodiment, in the above method, the wake-up signal at one of the plurality of opportunities is associated with the LP synchronization signal among the plurality of signals, and the rank of one of the plurality of opportunities among the plurality of opportunities is the same as the rank of the LP synchronization signal among the plurality of signals.

[0327] In one embodiment, the method further includes entering the LP mode by turning off the main mode. Here, the terminal device in the main mode performs at least one of paging monitoring, cell selection or reselection, measurement based on the primary synchronization signal (PSS), secondary synchronization signal (SSS) or channel state information-reference signal (CSI-RS), physical downlink control channel (PDCCH) monitoring, or uplink transmission.

[0328] In one embodiment, in the above method, the LP synchronization signal is different from the PSS or SSS received in the main mode.

[0329] The present disclosure provides a communication method. The communication method includes, at a terminal device, detecting a low power (LP) synchronization signal from a network device, determining a state of the terminal device with respect to the coverage of the LP synchronization signal based on the detection of the LP synchronization signal, and determining whether to wake up from the LP mode or report the state to the network device based on the state.

[0330] In one embodiment, in the above method, determining the state of the terminal device includes determining that the terminal device is out of coverage based on at least one of: not being able to receive the LP synchronization signal during a predetermined duration, not being able to receive the LP synchronization signal during a predetermined number of consecutive LP synchronization signal monitoring opportunities, the number of LP synchronization signals received normally during a predetermined duration being less than a threshold number, the number of LP synchronization signals received normally during a predetermined number of consecutive LP synchronization signal monitoring opportunities being less than a threshold number, the received signal strength of the LP synchronization signal being less than a threshold strength, the power ratio of the on symbol to the off symbol in the LP synchronization signal being less than a threshold ratio, the signal-to-noise ratio (SNR) of the LP synchronization signal being less than a threshold SNR, or receiving another LP synchronization signal different from the LP synchronization signal.

[0331] In one embodiment, the above method further includes waking up from the LP mode according to a determination that the terminal device is out of coverage and in the LP mode.

[0332] In one embodiment, the above method further includes selecting a cell according to a determination that the terminal device wakes up from the LP mode, and monitoring a paging message in the cell.

[0333] In one embodiment, the method further includes: selecting a cell according to a decision that the terminal device wakes up from the LP mode; and starting an initial access procedure according to a decision that a first tracking area code associated with the selected cell is different from a second tracking area code associated with an initial cell before the terminal device enters the LP mode.

[0334] In one embodiment, the method further includes: transmitting a report to a network device according to a decision that the terminal device is set to measure a detected LP synchronization signal and is in the RRC connected mode. The report includes at least one of measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal.

[0335] In one embodiment, the method further includes: starting an initial access procedure according to a decision that the terminal device is within coverage and is in the RRC idle mode or the non-active mode.

[0336] In one embodiment, the method further includes: transmitting a report including at least one of measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal, to the network device.

[0337] In one embodiment, in the above method, the report is included in message 3 or message A transmitted during the initial access procedure.

[0338] The present disclosure provides a communication method. The communication method includes: at a network device, generating an LP synchronization signal based on at least one of an identity (ID) of a cell group of the network device, an ID of a low power LP-SS group of the network device, a tracking area ID associated with the network device, or a tracking area code associated with the network device; and transmitting the LP synchronization signal to a terminal device in the LP mode.

[0339] In one embodiment, in the above method, the LP synchronization signal includes an amplitude modulation sequence.

[0340] In one embodiment, in the above method, the amplitude modulation sequence includes at least one on-off keying (OOK) on symbol and at least one OOK off symbol.

[0341] In one embodiment, in the above method, the LP synchronization signal is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of a network device or quasi-collocated (QCL) with a plurality of synchronization signal blocks (SSBs) transmitted by the network device.

[0342] In one embodiment, in the above method, the plurality of signals are based on a common amplitude modulation sequence and are transmitted at different time resources.

[0343] In one embodiment, in the above method, the plurality of signals are based on different amplitude modulation sequences, and each of the plurality of signals is associated with at least one of a subframe index, a slot index, or an index of the plurality of signals.

[0344] In one embodiment, the above method further includes transmitting a wake-up signal. The wake-up signal notifies the terminal device of at least one of staying in the LP mode, waking up from the LP mode, or the setting of the LP synchronization signal transmitted by the network device.

[0345] In one embodiment, in the above method, transmitting the wake-up signal includes transmitting the wake-up signal at one of a plurality of opportunities within a time window.

[0346] In one embodiment, in the above method, the wake-up signal at one of the multiple opportunities is associated with the LP synchronization signal among the multiple signals, and the rank of one of the multiple opportunities among the multiple opportunities is the same as the rank of the LP synchronization signal among the multiple signals.

[0347] In one embodiment, the above method further includes transmitting an indication of the initial HFN to the terminal device in the main mode.

[0348] In one embodiment, in the above method, the indication of the initial HFN is transmitted by one of system information, radio resource control (RRC) signaling, or packet data convergence protocol (PDCP) parameters.

[0349] In one embodiment, in the above method, the transmission period of the LP synchronization signal is equal to a plurality of hyperframes or a plurality of frames.

[0350] In one embodiment, the above method further includes receiving, from the terminal device, a report including at least one of measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal.

[0351] In one embodiment, in the above method, the report is included in message 3 or message A transmitted during the initial access procedure started by the terminal device.

[0352] In one embodiment, in the above method, the LP synchronization signal is different from the PSS or SSS received in the main mode.

[0353] The present disclosure provides a terminal device including a processor and a memory storing computer program code. The memory and the computer program code are configured to cause the terminal device, together with the processor, to execute the above-described method implemented on the terminal device.

[0354] The present disclosure provides a network device including a processor and a memory storing computer program code. The memory and the computer program code are configured to, together with the processor, cause the network device to execute the above-described method implemented on the network device.

[0355] The present disclosure provides a computer-readable medium storing instructions. When the instructions are executed by a processor of a device, the device is caused to execute the method implemented on the above-described terminal device or network device.

[0356] In general, various embodiments of the present disclosure may be implemented by hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects may be implemented by hardware, and other aspects may be implemented by firmware or software executable by a controller, a microprocessor, or other computing device. It will be understood that the various aspects of the embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or by some other pictorial representation, and the blocks, devices, systems, techniques, or methods described herein may be implemented, for example, by hardware, software, firmware, dedicated circuits or logic, general-purpose hardware or controllers or other computing devices, or any combination thereof, but are not limited thereto.

[0357] The present disclosure further provides at least one computer program product tangibly stored on a computer-readable non-transitory storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules. The instructions are executed on a device on a target physical processor or virtual processor, and execute a process or method as described above with reference to FIGS. 3 to 15. Usually, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. In various embodiments, the functions of the program modules may be combined or divided among the program modules as needed. The machine-readable instructions of the program modules may be executed within a local or distributed device. In a distributed device, the program modules may be placed on both local and remote storage media.

[0358] The program code for executing the method of the present disclosure may be described by any combination of one or more programming languages. The program code may be provided to a processor or controller of a general-purpose computer, a dedicated computer, or other programmable data processing device. When the program code is executed by the processor or controller, the functions / operations defined in the flowchart and / or block diagram are implemented. The program code may be executed entirely on a machine, partially on a machine, executed as an independent software package, partially executed on a machine and partially executed on a remote machine, or entirely executed on a remote machine or server.

[0359] The above program code may be embodied on a machine-readable medium, which may be any tangible medium that contains or stores 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. The machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine-readable storage medium include electrical connections including one or more wires, portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination of the foregoing.

[0360] Note that although the operations have been described in a particular order, it should be understood that in order to obtain the desired results, these operations may be performed in the particular order shown or sequentially, or all of the operations shown may be required to be performed. In some situations, multitasking and parallel processing may be advantageous. Similarly, although the above discussion includes some specific implementation details, these are not limitations on the scope of the present disclosure and should be construed as descriptions of features specific to a particular embodiment. Some features described in the context of individual embodiments may be implemented in combination in one embodiment. Conversely, various features described in the context of one embodiment may be implemented separately in multiple embodiments or in any suitable sub-combination.

[0361] Although this disclosure has been described in terms of language specific to structural features and / or methodological acts, it is to be understood that the disclosure defined by 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

1. In a terminal device in a low power (LP) mode, receiving from a network device an LP synchronization signal based on at least one of the identity (ID) of a cell group of the network device, the ID of an LP synchronization signal group of the network device, a tracking area ID associated with the network device, or a tracking area code associated with the network device; detecting a wake-up signal from the network device based on the LP synchronization signal; and including a communication method.

2. In a terminal device, detecting a low power (LP) synchronization signal from a network device; determining, based on the detection of the LP synchronization signal, a state of the terminal device with respect to the coverage of the LP synchronization signal; and determining, based on the state, whether to wake up from the LP mode or report the state to the network device; and including a communication method.

3. Determining the state of the terminal device includes not being able to receive an LP synchronization signal during a predetermined duration, not being able to receive an LP synchronization signal during a predetermined number of consecutive LP synchronization signal monitoring opportunities, the number of LP synchronization signals normally received during the predetermined duration being less than a threshold number, the number of LP synchronization signals normally received during the predetermined number of consecutive LP synchronization signal monitoring opportunities being less than the threshold number, the received signal strength of the LP synchronization signal being less than a threshold strength, the power ratio of an on symbol to an off symbol in the LP synchronization signal being less than a threshold ratio, the signal-to-noise ratio (SNR) of the LP synchronization signal being less than a threshold SNR, or receiving another LP synchronization signal different from the LP synchronization signal; and determining that the terminal device is outside the coverage based on at least one of the above, the method according to Claim 2.

4. Further including waking up from the LP mode according to a determination that the terminal device is outside the coverage and in the LP mode, the method according to Claim 2.

5. Selecting a cell according to a determination that the terminal device wakes up from the LP mode; monitoring a paging message in the cell; and including the method according to Claim 4.

6. selecting a cell according to a determination that the terminal device wakes up from the LP mode; starting an initial access procedure according to a determination that a first tracking area code associated with the selected cell is different from a second tracking area code associated with an initial cell before the terminal device enters the LP mode; further comprising; The method according to claim 3.

7. further comprising transmitting a report to the network device according to a determination that the terminal device is set to measure the detected LP synchronization signal and is in the RRC connected mode, wherein the report includes measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal at least one of which is included; The method according to claim 2.

8. further comprising starting an initial access procedure according to a determination that the terminal device is within the coverage and is in the RRC idle mode or the inactive mode; The method according to claim 2.

9. measurement results based on the LP synchronization signal, or assistance information for setting the LP mode or the LP synchronization signal further comprising transmitting a report including at least one of the above to the network device; The method according to claim 8.

10. wherein the report is included in message 3 or message A transmitted during the initial access procedure; The method according to claim 9.

11. In a network device, the identity (ID) of the cell group of the network device, the ID of the low power (LP) synchronization signal group of the network device, the tracking area ID associated with the network device, or the tracking area code associated with the network device generating an LP synchronization signal based on at least one of the above; transmitting the LP synchronization signal to a terminal device in the LP mode; including; A communication method.

12. wherein the LP synchronization signal is one of a plurality of signals, and the plurality of signals are associated with a plurality of transmission beams of the network device or quasi-collocated (QCL) with a plurality of synchronization signal blocks (SSB) transmitted by the network device; The method according to claim 11.

13. remaining in the LP mode, waking up from the LP mode, or Setting of the LP synchronization signal transmitted by the network device Further including transmitting a wake-up signal for notifying at least one of them to the terminal device The method according to claim 11

14. Transmitting the wake-up signal includes Transmitting the wake-up signal at one of a plurality of opportunities within a time window, The wake-up signal at one of the plurality of opportunities is associated with the LP synchronization signal among a plurality of signals, and the rank of one of the plurality of opportunities among the plurality of opportunities is the same as the rank of the LP synchronization signal among the plurality of signals, The method according to claim 33

15. Measurement results based on the LP synchronization signal, or LP mode or assistance information for setting the LP synchronization signal Further including receiving a report including at least one of them from the terminal device The method according to claim 11

16. The report is included in message 3 or message A transmitted during an initial access procedure started by the terminal device The method according to claim 15

17. The LP synchronization signal is different from the PSS or SSS received in the main mode The method according to claim 11

18. A terminal device, comprising A processor and A memory storing computer program code, Including The memory and the computer program code are set to cause the terminal device to execute the method according to any one of claims 1 to 10 together with the processor Terminal device

19. A network device, comprising A processor and A memory storing computer program code, Including The memory and the computer program code are set to cause the network device to execute the method according to any one of claims 11 to 17 together with the processor Network device

20. A computer-readable medium storing instructions, When the instructions are executed by a processor of a device, the instructions cause the device to execute the method according to any one of claims 1 to 17 Computer-readable medium

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