Method and apparatus for saving power of user equipment in wireless communication system

Abstract

The present disclosure relates to an operation method of a user equipment (UE) for saving power of the UE in a wireless communication system. The operating method includes receiving wakeup signal (WUS) configuration information from a base station (BS), monitoring a physical downlink control channel (PDCCH) based on the WUS configuration information, and stopping monitoring the PDCCH based on the WUS configuration information and operating in a short discontinuous reception (DRX) cycle when a specific event occurs during an active time.

Description

[0001] This application is a divisional application of the invention patent application with application date of May 4, 2020 and application number 202080032806.2. Technical Field

[0002] The present disclosure relates to a method and apparatus for saving power of a user equipment in a wireless communication system. Background Art

[0003] In order to meet the growing demand for wireless data services after the commercialization of the fourth generation (4G) communication system, people have been working hard to develop advanced fifth generation (5G) or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also called beyond 4G network communication systems or post-long term evolution (LTE) systems. Consider using ultra-frequency millimeter wave (mmWave) bands (for example, 60 gigahertz (GHz) bands) to implement 5G communication systems to achieve higher data transmission rates. In order to reduce the propagation loss of radio waves and increase the transmission distance in ultra-frequency bands, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technology are discussed. In order to improve the system network, advanced small cells, cloud radio access network (RAN), ultra-dense network, device-to-device (D2D) communication, wireless backhaul, mobile network, cooperative communication, coordinated multi-point (CoMP), receiving end interference elimination and other technologies are also being developed in 5G communication systems. In addition, in 5G systems, advanced coding modulation (ACM) such as hybrid frequency shift keying (FSK) and orthogonal amplitude modulation (QAM) (FQAM) and sliding window superposition coding (SWSC) have been developed, as well as advanced access technologies such as filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA).

[0004] In similar terms, the Internet is a human-centered connected network in which humans generate and consume information, and now the Internet is evolving into the Internet of Things (IoT), in which distributed entities (such as things) can send, receive and process information without human intervention. The Internet of Everything (IoE) has also emerged, which is a combination of IoT technologies such as big data processing technologies, such as through connections with cloud servers. In order to realize the IoT, various technologies are required, such as sensing technology, wired / wireless communication and network infrastructure, service interface technology and security technology, and recently even sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC) and other technologies for connecting things are being studied. Such an IoT environment can provide intelligent Internet Technology (IT) services to create new value for human life by collecting and analyzing data generated between connected objects. IoT can be applied to multiple fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart appliances and advanced medical services through the integration and combination of existing information technology (IT) and various industrial applications.

[0005] In this regard, various attempts are being made to apply 5G communication systems to IoT networks. For example, technologies related to sensor networks, M2M, MTC, etc. are implemented through 5G communication technologies, such as beamforming, MIMO, array antenna schemes, etc. Even the application of cloud radio access networks (cloud RAN) As mentioned above, big data processing technology can be regarded as an example of the fusion of 5G and IoT technologies.

[0006] With the development of the above-mentioned technologies and wireless communication systems, various services can be provided, and a method for smoothly providing services is needed. In particular, a communication method that saves power of user equipment is needed to provide users with services for a longer time.

[0007] The above information is presented as background information only to assist in understanding the present disclosure. No determination has been made, and no assertion has been made, as to whether any of the above information may be applicable as prior art with respect to the present disclosure. Summary of the invention

[0008] Technical Solution

[0009] One aspect of the present disclosure is to provide a communication method and apparatus for saving power of a user equipment in a wireless communication system.

[0010] According to one aspect of the present disclosure, a method for operating a user equipment (UE) in a wireless communication system for saving power of the UE is provided. The method includes receiving a wake-up signal (WUS) configuration information from a base station (BS), monitoring a physical downlink control channel (PDCCH) based on the WUS configuration information, and when a specific event occurs during an active time, stopping monitoring the PDCCH based on the WUS configuration information and operating in a short discontinuous reception (DRX) cycle.

[0011] Beneficial Effects

[0012] According to an embodiment of the present disclosure, a communication method and apparatus for saving power of user equipment in a wireless communication system are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent through the following description in conjunction with the accompanying drawings, in which:

[0014] Figure 1 The basic structure of the time-frequency domain in the mobile communication system according to the embodiment of the present disclosure is shown;

[0015] Figure 2 The frame, subframe and time slot structure in a mobile communication system according to an embodiment of the present disclosure is shown;

[0016] Figure 3 is a diagram of a configuration of a bandwidth part (BWP) of a mobile communication system according to an embodiment of the present disclosure;

[0017] Figure 4 is a diagram of a configuration of a control resource set of a downlink (DL) control channel of a mobile communication system according to an embodiment of the present disclosure;

[0018] Figure 5 is a structural diagram of a DL control channel of a mobile communication system according to an embodiment of the present disclosure;

[0019] Figure 6 is a diagram of discontinuous reception (DRX) according to an embodiment of the present disclosure;

[0020] Figure 7 is a diagram of long DRX and short DRX according to an embodiment of the present disclosure;

[0021] Figure 8is a diagram of a wake-up signal (WUS) according to an embodiment of the present disclosure;

[0022] Fig. 9 is a diagram showing identification of WUS opportunity zones according to an embodiment of the present disclosure;

[0023] Fig.10 is a diagram illustrating monitoring of a physical downlink control channel (PDCCH) for WUS reception when a WUS opportunity is located in an active time according to an embodiment of the present disclosure;

[0024] Fig.11 is a diagram of a format and size of downlink control information (DCI) corresponding to a WUS according to an embodiment of the present disclosure;

[0025] Fig.12 is a diagram of a method for performing one-to-one mapping between WUS and DRX according to an embodiment of the present disclosure;

[0026] Fig.13 is a diagram of a method for performing one-to-N mapping between WUS and DRX according to an embodiment of the present disclosure;

[0027] Fig.14 is a diagram of a method for performing one-to-N mapping between WUS and DRX according to an embodiment of the present disclosure, wherein WUS indicates whether a user equipment (UE) is awake with 1 bit;

[0028] Fig.15 is a diagram of a WUS indicating information about a time at which a UE will wake up during an active time according to an embodiment of the present disclosure;

[0029] Fig.16 is a diagram of the relationship between WUS monitoring operation and short DRX according to an embodiment of the present disclosure;

[0030] Fig.17 is a diagram of transmitting a WUS in each cell group including a plurality of cells according to an embodiment of the present disclosure;

[0031] Fig.18 is a diagram of sending a WUS in each cell according to an embodiment of the present disclosure;

[0032] Fig.19 is a sequence diagram illustrating a method for saving power of a UE in a wireless communication system according to an embodiment of the present disclosure;

[0033] Fig. 20 is a flowchart illustrating an operation of a UE performing a method for saving power of the UE in a wireless communication system according to an embodiment of the present disclosure;

[0034] Fig.21is a flowchart illustrating an operation of a UE performing a method for saving power of the UE in a wireless communication system according to an embodiment of the present disclosure;

[0035] Fig. 22 is a block diagram showing the structure of a UE according to an embodiment of the present disclosure; and

[0036] Fig.23 is a block diagram showing the structure of a BS according to an embodiment of the present disclosure.

[0037] Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures. DETAILED DESCRIPTION

[0038] Aspects of the present disclosure are intended to solve at least the above problems and / or disadvantages and provide at least the advantages described below. Therefore, one aspect of the present disclosure is to provide a communication method and apparatus for saving power of a user equipment in a wireless communication system.

[0039] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0040] According to one aspect of the present disclosure, a method for operating a user equipment (UE) for saving power in a wireless communication system is provided. The method includes receiving wake-up signal (WUS) configuration information from a base station (BS), monitoring a physical downlink control channel (PDCCH) based on the WUS configuration information, and stopping monitoring the PDCCH based on the WUS configuration information and operating in a short discontinuous reception (DRX) cycle when a specific event occurs during an active time.

[0041] Stopping monitoring of the PDCCH based on the WUS configuration information and operating in the short DRX cycle may include waking up and monitoring the PDCCH at a DRX opportunity corresponding to a WUS opportunity at which the PDCCH based on the WUS configuration information is not monitored.

[0042] The specific event may include reception of a PDCCH indicating at least one of uplink (UL) transmission or downlink (DL) transmission.

[0043] Stopping monitoring of the PDCCH based on the WUS configuration information and operating in a short DRX cycle may include starting a drx-ShortCycleTimer when a drx-onDurationTimer or a drx-InactivityTimer expires, and stopping monitoring of the PDCCH based on the WUS configuration information during operation of the drx-ShortCycleTimer.

[0044] The operating method may further include resuming monitoring the PDCCH based on the WUS configuration information and operating in the long DRX cycle when the drx-ShortCycleTimer stops or expires.

[0045] The operating method may further include waking up and monitoring the PDCCH at the DRX opportunity when the DRX opportunity after resuming monitoring the PDCCH based on the WUS configuration information and operating in the long DRX cycle corresponds to a WUS opportunity at which the PDCCH based on the WUS configuration information is not monitored during operation in the short DRX cycle.

[0046] The WUS configuration information may include a WUS offset and a WUS cycle.

[0047] The monitoring of the PDCCH may include monitoring or not monitoring the PDCCH when the WUS opportunity is in the active time, and the operation method may further include performing a specific operation at a DRX opportunity related to the WUS opportunity according to whether the PDCCH is monitored.

[0048] The operating method may further include receiving a WUS from the BS on a PDCCH, the WUS indicating whether the UE will wake up at a DRX opportunity, and waking up at a DRX opportunity related to the WUS based on the WUS.

[0049] The operating method may further include, when reception of a WUS fails, operating according to an instruction of a previously received WUS, performing a default operation, or skipping a DRX opportunity associated with a WUS that has not been received.

[0050] According to another aspect of the present disclosure, a UE in a wireless communication system is provided. The user equipment includes a transceiver, at least one memory storing a program for performing operations to save power of the UE, and at least one processor configured to execute the program to receive WUS configuration information from a BS, and monitor a PDCCH based on the WUS configuration information, and when a specific event occurs during an active time, stop monitoring the PDCCH based on the WUS configuration information and operate in a short DRX cycle.

[0051] The at least one processor may be further configured to wake up and monitor the PDCCH at a DRX timing corresponding to a WUS timing at which the PDCCH based on the WUS configuration information is not monitored.

[0052] The specific event may include reception of a PDCCH indicating at least one of UL transmission or DL ​​transmission.

[0053] The at least one processor may also be configured to start a drx-ShortCycleTimer when the drx-onDurationTimer or the drx-InactivityTimer expires, and stop monitoring the PDCCH based on the WUS configuration information during operation of the drx-ShortCycleTimer.

[0054] The at least one processor may be further configured to resume monitoring the PDCCH based on the WUS configuration information and operating in the long DRX cycle when the drx-ShortCycleTimer stops or expires.

[0055] The at least one processor may be further configured to, when a DRX opportunity after resuming monitoring of the PDCCH based on the WUS configuration information and operating in the long DRX cycle corresponds to a WUS opportunity at which the PDCCH based on the WUS configuration information was not monitored during operation in the short DRX cycle, wake up and monitor the PDCCH at the DRX opportunity.

[0056] The WUS configuration information may include a WUS offset and a WUS cycle.

[0057] The at least one processor may also be configured to monitor or not monitor the PDCCH when the WUS opportunity is in the active time, and perform a specific operation at a DRX opportunity related to the WUS opportunity according to whether the PDCCH is monitored.

[0058] The at least one processor may be further configured to receive a WUS indicating whether the UE wakes up at the DRX timing from the BS on the PDCCH, and wake up at the DRX timing related to the WUS based on the WUS.

[0059] The at least one processor may also be configured to, when reception of a WUS fails, perform a default operation according to an instruction of a previously received WUS, or skip a DRX opportunity associated with a WUS that has not been received.

[0060] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the accompanying drawings, discloses various embodiments of the disclosure.

[0061] Implementation

[0062] The following description is provided with reference to the accompanying drawings to assist in a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in understanding, but these are considered as examples only. Therefore, it will be appreciated by those of ordinary skill in the art that various changes and modifications may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, descriptions of known functions and configurations may be omitted for clarity and brevity.

[0063] The terms and words used in the following specification and claims are not limited to the bibliographic meanings, but are used by the inventors only to enable a clear and consistent understanding of the present disclosure. Therefore, it is apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustrative purposes only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0064] It should be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0065] While describing the embodiments of the present disclosure, technical contents that are well known in the relevant field and not directly related to the present disclosure will not be provided. By omitting redundant descriptions, the essence of the present disclosure will not be obscured and can be clearly explained.

[0066] For the same reason, some parts may be enlarged, omitted or schematically shown in the drawings for the sake of clarity. Moreover, the size of each element does not fully reflect the actual size. In the drawings, similar reference numerals represent similar elements.

[0067] Throughout the disclosure, the expression "at least one of a, b, and c" refers to only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.

[0068] Examples of the terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, a multimedia system capable of performing a communication function, and the like.

[0069] In this disclosure, a controller may also be referred to as a processor.

[0070] In this disclosure, a layer (or a layer device) may also be referred to as an entity.

[0071] When the following embodiments are read with reference to the accompanying drawings, the advantages and features of the present disclosure and the methods for realizing them will be more clearly understood. However, the embodiments of the present disclosure may be embodied in many different forms and should not be construed as being limited to the embodiments described herein; in contrast, these embodiments are provided so that the present disclosure will be comprehensive and complete, and the scope of the embodiments of the present disclosure will be fully conveyed to those skilled in the art. Similar figure numerals refer to similar elements throughout the specification. In the description of the present disclosure, when it is determined that a detailed description of a related function or configuration may unnecessarily obscure the subject matter of the present disclosure, the detailed description will be omitted. In addition, as described below, terms are defined by considering the functions in the present disclosure, but may vary according to the practice or intention of the user or operator. Therefore, terms should be defined according to the description in this specification.

[0072] Although the following embodiments will focus on long term evolution (LTE), advanced LTE (LTE-A), and new radio (NR) systems, they can be applied to other communication systems with similar technical backgrounds or channel types. For example, the NR system can be the fifth generation (5G) mobile communication technology developed after LTE-A, namely 5G NR, and the term "5G" used in this article can be a concept that includes existing LTE, LTE-A or other similar services. In addition, those of ordinary skill in the art will understand that the embodiments of the present disclosure will also be applied to different communication systems, such as worldwide interoperability for microwave access (WiMAX) and wireless broadband (WiBro), with some modifications without significantly departing from the scope of the present disclosure.

[0073] It should be understood that each block and combination of blocks of the flowchart can be performed by computer program instructions. The computer program instructions can be loaded onto a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that they generate a flowchart when the device for performing the functions described in the block is executed by the computer processor or other programmable data processing device. The computer program instructions can also be stored in a computer-usable or computer-readable memory for a computer or other programmable data processing device, so that a product containing instruction devices for performing the functions described in the flowchart blocks can be manufactured. The computer program instructions can also be loaded onto a computer or programmable data processing device, so that the instructions can generate a process performed by the computer or other programmable data processing device to provide operations for performing the functions described in the flowchart blocks.

[0074] In addition, each block may represent a portion of a module, segment, or code that includes one or more executable instructions for performing a specified logical function. It should also be noted that in some alternative implementations, the functions mentioned in the blocks may appear out of order. For example, two blocks shown in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order according to the corresponding functions.

[0075] The term "module" (or sometimes "unit") used herein refers to a software or hardware component that performs certain functions, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC). However, the module is not limited to software or hardware. The module can be configured to be stored in an addressable storage medium, or to execute one or more processors. For example, a module may include components, such as software components, object-oriented software components, class components and task components, processes, functions, attributes, programs, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, or variables. The functions provided by components and modules can be combined into a smaller number of components and modules, or further divided into a larger number of components and modules. In addition, components and modules can be implemented as executing a central processing unit (CPU) in a device or a secure multimedia card. In an embodiment, a module may include one or more processors.

[0076] Wireless communication systems are evolving from early systems that provided voice-oriented services to broadband wireless communication systems that provide high data rate and high quality packet data services, such as the 3rd Generation Partnership Project (3GPP), High Speed ​​Packet Access (HSPA), LTE or evolved universal terrestrial radio access (E-UTRA), LTE-A, LTE-Pro, high rate packet data (HRPD) and ultra mobile broadband (UMB) of 3GPP2 and IEEE 802.16e communication standards.

[0077] As a representative example of such a broadband wireless communication system, the LTE system adopts orthogonal frequency division multiplexing (OFDM) for the downlink (DL) and single carrier frequency division multiplexing (SC-FDMA) for the uplink (UL). UL refers to a wireless link for a terminal (ie, UE or MS) to send data or control signals to a BS (eg, an evolved Node B (eNB), a next generation Node B (gNB) or a Node B), and DL refers to a wireless link for a BS to send data or control signals to a terminal. The multiple access scheme allocates and operates time-frequency resources for carrying data or control information so that individual users do not overlap with each other, i.e., maintain orthogonality, thereby distinguishing the data or control information of each user. Not limited to this, and in a 5G communication system, the use of a non-orthogonal multiple access (NOMA) scheme and an OFDM scheme for UL is also considered.

[0078] As the future communication system after LTE, the 5G communication system needs to freely reflect the various needs of users and service providers, thereby supporting services that meet various needs at the same time. The services considered by the 5G communication system may include enhanced mobile broadband (eMBB), massive machine type communication (mMTC), ultra-reliable low latency communication (URLLC), etc.

[0079] eMBB is designed to provide more enhanced data rates than LTE, LTE-A or LTE-Pro may support. For example, in a 5G communication system, eMBB is required to provide a peak data rate of 20Gbps in DL and a peak data rate of 10Gbps in UL for a single BS. In addition, the 5G communication system needs to provide an increased user-perceived data rate while providing the peak data rate. In order to meet these requirements, it is necessary to enhance various technologies for transmission or reception, including multiple-input multiple-output (MIMO) transmission technology. While LTE uses a transmission bandwidth of up to 20MHz in the 2GHz band for signal transmission, the 5G communication system can use a frequency bandwidth wider than 20MHz in the 3 to 6GHz band or the 6GHz or higher band, thereby meeting the data rate required by the 5G communication system.

[0080] In addition, in the 5G communication system, mMTC is considered to support application services such as Internet of Things (IoT) application services. In order for mMTC to effectively provide IoT, it is necessary to support access from a large number of terminals in the cell, enhance the coverage of the terminal, extend the battery time, reduce the price of the terminal, etc. Because IoT is equipped with various sensors and devices to provide communication functions, it may be considered to support a large number of terminals in the cell (for example, 1,000,000 terminals / square kilometer). In addition, terminals supporting mMTC are more likely to be located in shadow areas, such as underground buildings, which may not be covered by the cell due to the nature of the service, so mMTC may require greater coverage than other services provided by the 5G communication system. Terminals supporting mMTC need to be low-cost terminals and may require a battery life of 10 to 15 years because the batteries in the terminals are difficult to replace frequently.

[0081] Finally, URLLC is a cellular-based mission-critical wireless communication service. For example, URLLC can provide services for robot or machinery remote control, industrial automation, drones, telemedicine, emergency alerts, etc. Therefore, the communication provided by URLLC requires very low latency (ultra-low latency) and very high reliability. For example, URLCC services need to meet sub-millisecond (less than 0.5 milliseconds) air interface latency, while requiring an error rate of less than 1 packet lost in 105 packets. Therefore, for URLCC services, 5G systems need to provide smaller transmission time intervals (transmit time intervals, TTIs) that are different from other services, and a design that allocates extensive resources to frequency bands is required to ensure the reliability of the communication link.

[0082] The three services (eMBB, URLLC, and mMTC) in 5G can be multiplexed in a single system for transmission. In such a case, in order to meet the different requirements of the three services, different transmission or reception schemes and parameters can be used between the services. However, 5G is not limited to these three services.

[0083] In the following description, a method for monitoring downlink control information (DCI) corresponding to a power saving signal and a physical downlink control channel (PDCCH) for detecting DCI corresponding to a power saving signal, as well as a method for performing power saving based on the detected DCI performed by a terminal are provided.

[0084] A frame structure of a next-generation mobile communication system (5G or NR system) will now be described in detail with reference to the accompanying drawings.

[0085] Figure 1 The basic structure of the time-frequency domain in the next generation mobile communication system according to an embodiment of the present disclosure is shown.

[0086] refer to Figure 1 , the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic resource unit in the time domain and the frequency domain is a resource element (RE) 101. RE 101 can be defined as an OFDM symbol 102 on the time axis and a subcarrier 103 on the frequency axis. In the frequency domain, consecutive REs (e.g. Figure 1 Twelve REs (shown) may constitute a single resource block (RB) 104. In one embodiment of the present disclosure, a plurality of OFDM symbols may constitute a subframe 110.

[0087] Figure 2 The frame, subframe and time slot structures in the next generation mobile communication system according to an embodiment of the present disclosure are shown.

[0088] refer to Figure 2 , shows a disclosed embodiment of a frame 200, a subframe 201, and a time slot 202 structure. A frame 200 may be defined as having a length of 10 ms. A subframe 201 may be defined as having a length of 1 ms. That is, a frame 200 may include a total of 10 subframes 201.

[0089] In the embodiment of the present disclosure, one time slot 202 or time slot 203 may be defined as having 14 OFDM symbols (ie, the number of symbols per time slot is One subframe 201 may include one or more time slots 202 or 203, and the number of time slots 202 and 203 per one subframe may vary according to the subcarrier spacing configuration value μ (204 and 205). Figure 2 In the example of , the subcarrier spacing configuration value is 0 and 1, that is, μ = 0 (204) and μ = 1 (205). In the case of μ = 0 (204), one subframe 201 includes one time slot 202, and in the case of μ = 1 (205), one subframe 201 includes two time slots 203. That is, depending on the subcarrier spacing configuration value μ, the number of time slots per subframe is May vary and the number of slots per frame May change accordingly. Depends on the subcarrier spacing configuration value μ as well as Can be defined according to Table 1.

[0090] [Table 1]

[0091]

[0092] Figure 3 An example of configuring a bandwidth part (BWP) in a 5G communication system according to an embodiment of the present disclosure is shown.

[0093] refer to Figure 3In the embodiment of the present disclosure, two BWPs, BWP#1 301 and BWP#2 302, are configured in the UE bandwidth 300. The BS may configure one or more BWPs for the UE, and configure each BWP with information as shown in Table 2 below.

[0094] [Table 2]

[0095]

[0096] The present disclosure is not limited to the above examples, and in addition to the configured information, various parameters related to the BWP may be configured for the UE. The above information may be sent from the BS to the UE via high-layer signaling (e.g., radio resource control (RRC)) or in system information such as a master information block (MIB). At least one of the configured one or more BWPs may be activated. The UE may be notified of the activated configured BWP semi-statically from the BS via RRC signaling, or dynamically in the DCI.

[0097] In an embodiment of the present disclosure, before the UE is connected by RRC, the BS may configure the UE in the MIB for initial access using the initial BWP. For example, the UE may receive configuration information of a control resource set (CORESET) and a search space, wherein the search space may send a PDCCH for receiving system information required for initial access in the MIB during the initial access process (corresponding to the remaining system information (RMSI) or system information block 1 (SIB1)). The control resource set and search space configured in the MIB may be respectively regarded as identification (ID) 0.

[0098] The BS may notify the UE of configuration information of the control resource set #0 in the MIB, such as frequency allocation information, time allocation information, numerology, etc. The BS may also notify the UE of configuration information such as the monitoring period and timing of the control resource set #0, that is, information of the configuration information search space #0. The UE may regard the frequency region configured as the control resource set #0 obtained from the MIB as the initial BWP for initial access. In this case, the ID of the initial BWP may be regarded as 0.

[0099] The configuration of the BWP supported by the next-generation mobile communication system (5G or NR system) can be used for various purposes.

[0100] In the embodiments of the present disclosure, when the bandwidth supported by the UE is less than the system bandwidth, it can be solved by the BWP configuration of the BS. For example, the BS can use the frequency position of the BWP (configuration information 2) to configure the UE, thereby allowing the UE to send or receive data at a specific frequency position in the system bandwidth.

[0101] In addition, in an embodiment of the present disclosure, in order to support different numerologies, the BS may configure multiple BWPs for the UE. For example, for a specific UE, in order to support data transmission and reception using both a subcarrier spacing of 15 KHz and a subcarrier spacing of 30 KHz, the BS may configure two BWP carriers with subcarrier spacings of 15 KHz and 30 KHz, respectively. Different BWPs may be frequency-division multiplexed. In order to transmit and receive data at a specific subcarrier spacing, a BWP configured at a specific subcarrier spacing may be activated.

[0102] In addition, in an embodiment of the present disclosure, in order to reduce the power consumption of the UE, the BS may configure a BWP with different bandwidth sizes for the UE. For example, when the UE supports a very large bandwidth (e.g., a 100 MHz bandwidth) and always sends or receives data in the bandwidth, the UE may consume very large power. Especially in the absence of business, monitoring unnecessary DL control channels in a large 100 MHz bandwidth may be very inefficient in terms of power consumption. In order to reduce the power consumption of the UE, the BS may configure a BWP with a relatively small bandwidth, such as a 20 MHz BWP, for the UE. In the absence of business, the UE may perform monitoring in the 20 MHz BWP, and when data occurs, the UE may send or receive data in the 100 MHz BWP according to instructions from the BS.

[0103] In the method of configuring BWP, the UE may receive configuration information of the initial BWP in the MIB during the initial access process before the RRC connection. For example, the UE may be configured with a control region (e.g., CORESET) for a DL control channel in which DCI may be sent from the MIB of the physical broadcast channel (PBCH) to schedule SIBs. The bandwidth of the control resource set configured in the MIB may be regarded as the initial BWP, and the UE may receive the PDSCH on which the SIB is transmitted in the initial BWP. In addition to the reception of SIBs, the initial BWP may also be used for other system information (OSI), paging, or random access.

[0104] The synchronization signal (SS) / PBCH block of the next generation mobile communication system (5G or NR system) will now be described.

[0105] The SS / PBCH block may refer to a physical layer channel block including a primary SS (PSS), a secondary SS (SSS), and a PBCH. For example, the SS / PBCH block may be defined as follows:

[0106] -PSS: A reference signal for DL ​​time / frequency synchronization, which can provide part of the cell ID information.

[0107] -SSS: A reference signal used for DL ​​time / frequency synchronization, which can provide residual cell ID information not provided by PSS. It can also be used as an additional reference signal for PBCH demodulation.

[0108] -PBCH: A channel that can provide the UE with basic system information required for the transmission or reception of data channels and control channels. The basic system information may include search space-related control information indicating radio resource mapping information of control channels and additional data channel scheduling control information for transmitting system information.

[0109] -SS / PBCH block: SS / PBCH block is a combination of PSS, SSS and PBCH. One or more SS / PBCH blocks can be transmitted within 5ms, and each SS / PBCH block can be distinguished by an index.

[0110] The UE may detect the PSS and SSS during the initial access process and decode the PBCH. The UE may obtain the MIB from the PBCH and may be configured with control resource set #0 in the MIB. The UE may assume that the demodulation reference signal (DMRS) and control resource set #0 sent in the selected SS / PBCH block are quasi-colocated (QCL) and perform monitoring on control resource set #0. The UE may receive system information in the DL control information sent in control resource set #0. The UE may obtain random access channel (RACH) related configuration information required for initial access from the received system information. Considering the selected SS / PBCH index, the UE may send a physical RACH (PRACH) to the BS, and upon receiving the PRACH, the BS may obtain information about the SS / PBCH block index selected by the UE. The BS may know that the UE has selected any one of the corresponding SS / PBCH blocks and that the UE is monitoring the control resource set #0 corresponding to (or associated with) the selected SS / PBCH.

[0111] DCI in the next generation mobile communication system (5G or NR system) will now be described in detail.

[0112] In the next generation mobile communication system (5G or NR system), scheduling information of UL data (or physical uplink shared channel (PUSCH)) or DL ​​data (or physical downlink shared channel (PDSCH)) in DCI can be sent from the BS to the UE. The UE can monitor the fallback DCI format and non-fallback DCI format for PUSCH or PDSCH. The fallback DCI format may include a fixed field predefined between the BS and the UE, and the non-fallback DCI format may include a configurable field.

[0113] After undergoing the channel coding and modulation process, the DCI can be sent on the physical downlink control channel (PDCCH). A cyclic redundancy check (CRC) can be attached to the DCI message payload, and the CRC can be scrambled by the radio network temporary identifier (RNTI) corresponding to the UE's ID. Depending on the use of the DCI message, for example, UE-specific data transmission, power control commands, random access responses, etc., different RNTIs can be used to scramble the CRC attached to the payload of the DCI message. In other words, the RNTI may not be transmitted explicitly, but rather during the CRC calculation process. When a DCI message is received on the PDCCH, the UE can check the CRC using the assigned RNTI. When the result of the CRC check is correct, the UE can determine that the message is sent to the UE.

[0114] For example, the DCI for scheduling PDSCH for system information (SI) may be scrambled by SI-RNTI. The DCI for scheduling PDSCH for random access response (RAR) message may be scrambled by RA-RNTI. The DCI for scheduling PDSCH for paging message may be scrambled by P-RNTI. The DCI for notifying slot format indicator (SFI) may be scrambled by SFI-RNTI. The DCI for notifying transmit power control (TPC) may be scrambled by TPC-RNTI. The DCI for scheduling UE-specific PDSCH or PUSCH may be scrambled by cell RNTI (C-RNTI).

[0115] DCI format 0_0 may be used to schedule fallback DCI for PUSCH, in which case the CRC may be scrambled by C-RNTI. In an embodiment of the present disclosure, DCI format 0_0 with CRC scrambled by C-RNTI may include information as shown in Table 3.

[0116] [Table 3]

[0117]

[0118]

[0119] DCI format 0_1 ​​may be used to schedule non-fallback DCI for PUSCH, in which case the CRC may be scrambled by C-RNTI. In an embodiment of the present disclosure, DCI format 0_1 ​​with CRC scrambled by C-RNTI may include information as shown in Table 4.

[0120] [Table 4]

[0121]

[0122]

[0123] DCI format 1_0 may be used to schedule fallback DCI for PDSCH, in which case the CRC may be scrambled by C-RNTI. In an embodiment of the present disclosure, DCI format 1_0 with CRC scrambled by C-RNTI may include information as shown in Table 5.

[0124] [Table 5]

[0125]

[0126]

[0127] DCI format 1_1 may be used to schedule non-fallback DCI for PUSCH, in which case the CRC may be scrambled by the C-RNTI. In an embodiment of the present disclosure, DCI format 1_1 with CRC scrambled by the C-RNTI may include information as shown in Table 6.

[0128] [Table 6]

[0129]

[0130]

[0131] Figure 4 is a diagram for describing a configuration of a control resource set of a DL control channel of a next generation mobile communication system according to an embodiment of the present disclosure. Figure 4 An example of a CORESET for transmitting a DL control channel in a 5G wireless communication system according to an embodiment of the present disclosure is shown.

[0132] refer to Figure 4 , the UE BWP 410 is configured on the frequency axis, and two control resource sets, namely control resource set #1 401 and control resource set #2 402, are configured on the time axis of the time slot 420. The control resource sets 401 and 402 may be configured in a specific frequency resource 403 in the entire UE BWP 410 on the frequency axis. The control resource sets 401 and 402 may be configured on the time axis by one or more OFDM symbols and defined by a control resource set duration 404. Figure 4 , control resource set #1 401 may be configured to have a control resource set duration of two symbols, and control resource set #2 402 may be configured to have a control resource set duration of one symbol.

[0133] As described above, in the next generation mobile communication system (5G or NR system), the BS may configure a control resource set for the UE through high-level signaling (e.g., system information, MIB, or RRC signaling). Configuring the UE with a control resource set means providing the UE with information such as a control resource set ID, a frequency position of the control resource set, and a symbol length of the control resource set. For example, the configuration of the control resource set may include information as shown in Table 7.

[0134] [Table 7]

[0135]

[0136] In Table 7, the tci-StatesPDCCH (hereinafter referred to as "TCI state") configuration information may include information about one or more SS / PBCH block indices that have a QCL relationship with a DMR transmitted in a corresponding control resource set or channel state information reference signal (CSI-RS) index.

[0137] Figure 5 is a diagram for describing a structure of a DL control channel of a next generation mobile communication system according to an embodiment of the present disclosure.

[0138] Figure 5 An example of a basic unit of time and frequency resources forming a DL control channel to be used in 5G according to an embodiment of the present disclosure is shown.

[0139] refer to Figure 5 , the basic unit of time and frequency resources forming the control channel can be defined as a resource element group (REG) 503. REG 503 can be defined by one OFDM symbol 501 on the time axis and one physical resource block (PRB) 502 (i.e., 12 subcarriers) on the frequency axis. The BS can configure the DL control channel allocation unit by connecting REG 503.

[0140] exist Figure 5 In the embodiment, when the DL control channel allocation unit is called a control channel element (CCE) 504 in 5G, a CCE 504 may include multiple REGs 503. For example, Figure 5As shown, REG 503 may include 12 REs, and when one CCE 504 includes 6 REGs 503, one CCE 504 may include 72 REs. When a DL control resource set is configured, it may include multiple CCEs 504, and a specific DL control channel may be transmitted by mapping to one or more CCEs 504 based on an aggregation level (AL) in the control resource set. CCEs 504 in the control resource set may be distinguished by numbers, which may be allocated to CCEs 504 by a logical mapping method.

[0141] like Figure 5 The basic unit of the DL control channel shown, that is, REG 503, may include both REs to which DCI is mapped and regions to which DMRS 505, which is a reference signal for decoding DCI, is mapped. Figure 5 As shown, three DMRS 505 can be sent in one REG 503. Depending on AL, the number of CCEs required to send PDCCH can be 1, 2, 4, 8 or 16, and different numbers of CCEs can be used to achieve link adaptation of DL control channels. For example, when AL=L, a single downlink control channel can be sent in L CCEs.

[0142] The UE needs to detect the signal without knowing the information about the DL control channel, and a search space representing a set of CCEs can be defined for blind decoding. The search space can be a set of DL control channel candidates, including CCEs that the UE attempts to decode at a given AL. Since there may be various ALs that group 1, 2, 4, 8, or 16 CCEs into groups, the UE may have multiple search spaces. A search space set can be defined as the set of search spaces over all set ALs.

[0143] The search space can be divided into a common search space and a UE-specific search space. In an embodiment of the present disclosure, a group of specific UEs or all UEs may check the common search space of the PDCCH to dynamically schedule system information or receive cell common control information, such as a paging message.

[0144] For example, the UE can receive PDSCH scheduling allocation information for sending SIBs including cell operator information, etc. by checking the common search space of the PDCCH. For the common search space, a specific group of UEs or all UEs need to receive the PDCCH, so the common search space can be defined as a set of pre-appointed CCEs. The UE can receive UE-specific PDSCH or PUSCH scheduling allocation information by checking the UE-specific search space of the PDCCH. The UE-specific search space can be a function of the UE, specifically defined as various system parameters and the UE's ID.

[0145] In the 5G system, the parameters of the search space of the PDCCH may be configured by the BS for the UE in high-level signaling (e.g., SIB, MIB, or RRC signaling). For example, the BS may configure the number of PDCCH candidates at each ALL, the monitoring period of the search space, the monitoring timing in the symbol in the time slot of the search space, the type of the search space (common search space or UE-specific search space), the combination of the DCI format and RNTI to be monitored in the search space, the control resource set index to monitor the search space of the UE, etc. For example, the configuration may include information as shown in Table 8.

[0146] [Table 8]

[0147]

[0148] Based on the configuration information, the BS may configure the UE with one or more search space sets. In one embodiment of the present disclosure, the BS may configure the UE with search space set 1 and search space set 2, and configure the UE to monitor DCI format A scrambled by X-RNTI in search space set 1 in the common search space, and monitor DCI format B scrambled by Y-RNTI in search space set 2 in the UE-specific search space.

[0149] The configuration information may indicate that one or more search space sets exist in a common or UE-specific search space. For example, search space set #1 and search space set #2 may be configured as common search spaces, and search space set #3 and search space set #4 may be configured as UE-specific search spaces.

[0150] In the common search space, the following combinations of DCI formats and RNTIs may be monitored. Of course, it is not limited to the following examples.

[0151] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

[0152] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0153] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0154] - DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0155] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0156] In the UE-specific search space, the following combinations of DCI formats and RNTIs may be monitored. Of course, it is not limited to the following examples.

[0157] - DCI format 0_0 / 1_0 of CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0158] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0159] The enumerated RNTIs may follow the following definitions and uses.

[0160] C-RNTI (Cell RNTI): used for PDSCH scheduling of a specific UE

[0161] TC-RNTI (Temporary Cell RNTI): used for PDSCH scheduling of a specific UE

[0162] CS-RNTI (Configured Scheduling RNTI): used for semi-statically configured PDSCH scheduling of a specific UE

[0163] RA-RNTI (Random Access RNTI): used for PDSCH scheduling during random access

[0164] P-RNTI (Paging RNTI): used to schedule the PDSCH for sending paging messages

[0165] SI-RNTI (System Information RNTI): PDSCH used to schedule transmission of system information

[0166] INT-RNTI (interrupt RNTI): used to indicate whether to puncture PDSCH

[0167] TPC-PUSCH-RNTI (Transmit Power Control of PUSCH RNTI): used to indicate the power control command of PUSCH

[0168] TPC-PUCCH-RNTI (Transmit Power Control of PUCCH RNTI): used to indicate the power control command of PUCCH

[0169] TPC-SRS-RNTI (SRS RNTI Transmit Power Control): used to indicate the power control command of SRS

[0170] In an embodiment of the present disclosure, the DCI format described above may be defined as shown in Table 9.

[0171] [Table 9]

[0172]

[0173]

[0174] In one embodiment of the present disclosure, in a 5G system, in the case of controlling a resource set p and a search space set s, the search space at the ALL can be expressed as Equation 1.

[0175]

[0176] L: Aggregation level

[0177] n CI : Carrier index

[0178] N CCE，p : The total number of CCEs in control resource set p

[0179] Time slot index

[0180] At AL=L, the number of PDCCH candidates

[0181] At AL=L, the index of the PDCCH candidate is i=0, ..., L-1

[0182] Y p-1 =n RNTI ≠0,A 0 =39827,A 1 =39829, A 2 =39839,D=65537

[0183] nRNTI: UE identifier

[0184] ...Equation 1

[0185] In the embodiment of the present disclosure, for the public search space, The value of may correspond to 0.

[0186] In the embodiments of the present disclosure, The value of may correspond to a value that changes according to a UE identity (C-RNTI or ID configured by the BS for the UE) and a time index of a UE-specific search space.

[0187] In an embodiment of the present disclosure, in 5G, multiple search space sets may be configured with different parameters (e.g., parameters as in Table 8). Therefore, the search space set to be monitored by the UE may change at each time point. For example, when search space set #1 is configured with an X time slot period and search space set #2 is configured with a Y time slot period, where X and Y are different, the UE may monitor search space set #1 and search space set #2 in a specific time slot, and monitor one of search space set #1 and search space set #2 in another specific time slot.

[0188] When multiple search space sets are configured for a UE, the search space set to be monitored by the UE may be determined considering the following conditions.

[0189] Condition 1: Limit the maximum number of PDCCH candidates

[0190] The number of PDCCH candidates to be monitored in each time slot may not exceed M μ . M μ It can be defined as a configuration with a subcarrier spacing of 15·2 μ The maximum number of PDCCH candidates per time slot in a cell of kHz is shown in Table 10.

[0191] [Table 10]

[0192] μ <![CDATA[For each serving cell (M μ ) and the maximum number of PDCCH candidates per time slot]]> 0 44 1 36 2 22 3 20

[0193] Condition 2: Limiting the maximum number of CCEs

[0194] The number of CCEs in each time slot that constitutes the entire search space (the entire search space in this article refers to the entire CCE set corresponding to the union of multiple search space sets) may not exceed C μ . C μ can be defined as a configuration with a subcarrier spacing of 15·2 μ The maximum number of CCEs per timeslot in a kHz cell is shown in Table 11.

[0195] [Table 11]

[0196] μ <![CDATA[For each serving cell (C μ ) and the maximum number of CCEs per time slot]]> 0 56 1 56 2 48 3 32

[0197] For ease of explanation, a case where both conditions 1 and 2 are simultaneously satisfied at a specific time may be defined as “condition A.” Therefore, failure to satisfy condition A may mean that at least one of conditions 1 or 2 is not satisfied.

[0198] Depending on how the BS configures the search space sets, there may be a time when condition A is not satisfied at a specific time. When condition A is not satisfied at a specific time, the UE may select and monitor some search space sets that are configured to satisfy condition A at that time, and the BS may send the PDCCH in the selected search space sets.

[0199] In an embodiment of the present disclosure, some of the entire search space set may be selected by the following method.

[0200] Method 1

[0201] When the condition A of PDCCH is not satisfied within a specific time (time slot),

[0202] The UE may select a search space set having a search space type configured as a common search space from among the search space sets existing at the time, over the search space set configured for the UE-specific search space.

[0203] When all search space sets configured for the common search space are selected (i.e., although all search spaces configured for the common search space are selected, condition A is satisfied), the UE (or BS) may select a search space set configured for the UE-specific space. In such a case, when there are multiple search space sets configured for the UE-specific search space, a search space set with a lower search space index may have a higher priority. Considering the priority, the UE or BS may select a UE-specific search space set as long as the UE-specific search space set satisfies condition A.

[0204] A time domain resource allocation method for a data channel in a next-generation mobile communication system (5G or NR system) will now be described.

[0205] The BS may configure a time domain resource allocation information table of a DL data channel (physical downlink shared channel, PDSCH) and a UL data channel (physical uplink shared channel, PUSCH) for the UE through high-layer signaling (e.g., RRC signaling). For PDSCH, a table including up to 16 (maxNrofDL-Allocations=16) entries may be configured, and for PUSCH, a table including up to 16 (maxNrofDL-Allocations=16) entries may be configured. In an embodiment of the present disclosure, the time domain resource allocation information may include PDCCH to PDSCH slot timing (corresponding to the time interval in the slot between the PDCCH reception time and the PDSCH transmission time scheduled on the received PDCCH, and represented as K0), PDCCH to PUSCH slot timing (corresponding to the time interval in the slot between the PDCCH reception time and the PUSCH transmission time scheduled on the received PDCCH, and represented as K2), information about the position and length of the start symbol scheduled on the PDSCH or PUSCH in the slot, the mapping type of the PDSCH or PUSCH, etc. For example, the information in Table 12 or Table 13 can be notified to the UE from the BS.

[0206] [Table 12]

[0207]

[0208] [Table 13]

[0209]

[0210] The BS may notify the UE of at least one of the entries in the table regarding the time domain resource allocation information through L1 signaling (e.g., in DCI, particularly in the "time domain resource allocation" field in the DCI). The UE may obtain the time domain resource allocation information of the PDSCH or PUSCH based on the DCI received from the BS.

[0211] A method of measuring and reporting channel status in a next-generation mobile communication system (5G or NR system) will now be described.

[0212] The channel state information (CSI) may include channel quality information (CQI), precoding matrix indicator (PMI), CSI-RS resource indicator (CRI), SS / PBCH block resource indicator (SSBRI), layer indicator (LI), rank indicator (RI), and / or L1 reference signal received power (L1-RSRP). The BS may control the time and frequency resources used for CSI measurement and reporting of the aforementioned UE.

[0213] For the aforementioned CSI measurement and reporting, the UE may be configured with configuration information for N (≥1) CSI reports (CSI-ReportConfig), configuration information for M (≥1) RS transmission resources (CSI-ResourceConfig), and information about one or two trigger state lists (CSI-AperiodicTriggerStateList (CSI-aperiodic trigger state list), CSI-SemiPersistentOnPUSCH-TriggerStateList (CSI-PUSCH semi-persistent-trigger state list)) in high-level signaling.

[0214] Figure 6 is a diagram for describing discontinuous reception (DRX) according to an embodiment of the present disclosure.

[0215] DRX is an operation of discontinuously receiving data in an RRC connected state in which a wireless link is established between the UE and the BS using a service. When DRX is applied, the UE can turn on the receiver at a specified time to monitor the control channel and turn off the receiver when no data is received within a specific period of time, thereby reducing the power consumption of the UR. The DRX operation can be controlled by a medium access control (MAC) layer device based on various parameters and timers.

[0216] refer to Figure 6 , the active time 605 is the time period during which the UE wakes up and monitors the PDCCH in each DRX cycle. The active time 605 can be defined as follows:

[0217] - drx-onDurationTimer (drx duration timer) or drx-InactivityTimer (drx inactivity timer) or drx-RetransmissionTimerDL (drx DL retransmission timer) or drx-RetransmissionTimerUL (drx UL retransmission timer) or ra-ContentionResolutionTimer (random access contention resolution timer) is running; or

[0218] - A scheduling request is sent on the PUCCH and is pending; or

[0219] - After a random access response to a random access preamble that is not selected by the MAC entity among contention-based random access preambles is successfully received, a PDCCH indicating information transmission of a C-RNTI addressed to the MAC entity has not been received.

[0220] drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, drx-RetransmissionTimerUL, ra-ContentionResolutionTimer, etc. are timers whose values ​​are configured by the BS and have a function of configuring the UE to monitor the PDCCH when a specific condition is met.

[0221] drx-onDurationTimer 615 is a parameter for configuring the minimum time that the UE stays awake. drx-InactivityTimer 620 is a parameter for configuring the additional time period that the UE additionally stays awake when a PDCCH 630 indicating a new UL or DL ​​transmission is received. drx-RetransmissionTimerDL is a parameter for configuring the maximum time period that the UE stays awake to receive DL retransmissions in a DL HARQ process. drx-RetransmissionTimerUL is a parameter for configuring the maximum time period that the UE stays awake to receive UL retransmission grants in an UL HARQ process. drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL and drx-RetransmissionTimerUL can be configured with, for example, a time, a number of subframes or a number of time slots. ra-ContentionResolutionTimer is a parameter for monitoring PDCCH in a random access procedure.

[0222] The inactive time 610 is the time when the PDCCH does not need to be monitored or received during the DRX operation. The inactive time 610 may be all the time when the DRX operation is performed except the active time 605. When the PDCCH is not monitored during the active time 605, the UE may enter a sleep or inactive state to reduce power consumption.

[0223] The DRX cycle refers to the cycle in which the UE wakes up and monitors the PDCCH. For example, it refers to the time interval from when the UE monitors the PDCCH to when it monitors the next PDCCH, or the occurrence cycle of the duration. There are two types of DRX cycles: short DRX cycle 705 (also known as drx-ShortCycle) and long DRX cycle 625 (also known as drx-LongCycle). The short DRX cycle 705 can be applied selectively.

[0224] The long DRX cycle 625 is the longer of the two DRX cycles configured for the UE. During the long DRX operation, the UE restarts the Drx-onDurationTimer 615 at a time point after the long DRX cycle 625 has passed from the starting point (e.g., the start symbol) of the drx-onDurationTimer 615. Figure 7 Describe the short DRX cycle.

[0225] When operating in a long DRX cycle 625, the UE may start the drx-onDurationTimer in a slot after drx-SlotOffset from the start of a subframe satisfying the following Equation 2. drx-SlotOffset refers to the delay before the start of the drx-onDurationTimer 615. drx-SlotOffset may be configured with, for example, time, number of slots, etc.

[0226] [(SFN x 10) + number of subframes] modulo (drx-LongCycle) = drx-StartOffset

[0227] …Equation 2

[0228] Among them, the long DRX cycle 625 and drx-StartOffset (e.g., drx-LongCycleStartOffset) can be used to define the subframe that starts the long DRX cycle 625. The drx-StartOffset (e.g., drx-LongCycleStartOffset) can be configured with, for example, time, number of subframes, number of time slots, etc.

[0229] Figure 7 is a diagram for describing long DRX and short DRX according to an embodiment of the present disclosure.

[0230] refer to Figure 7, the short DRX cycle 705 is the shorter of the two DRX cycles defined for the UE. The UE operating in the long DRX cycle 625 starts or restarts the drx-InactivityTimer 620 when a specific event occurs in the active time 605 (e.g., receiving a PDCCH 630 indicating a new UL transmission or DL ​​transmission), and operates in the short DRX cycle 705. For example, the UE starts the drx-ShortCycleTimer 710 when the previous drx-onDurationTimer 615 or drx-InactivityTimer 620 expires, and operates in the short drx cycle until the drx-ShortCycleTimer 710 expires. The drx-ShortCycleTimer 710 can be started or restarted according to a MAC Control Element (CE) indicated by the BS. Upon receiving a PDCCH 630 indicating a new UL transmission or DL ​​transmission, the UE may anticipate additional UL transmissions or DL ​​transmissions in the future and extend the active time 605 or delay the start of the inactive time 610. When operating in a short DRX cycle, the UE restarts the drx-onDurationTimer 615 at a time point after the short DRX cycle has passed from the start point of the previous duration. Thereafter, when the drx-ShortCycleTimer 710 expires, the UE operates in a long DRX cycle 625 again.

[0231] When operating in the short DRX cycle 705, the UE may start the drx-onDurationTimer 615 after the drx-SlotOffset in the subframe satisfying Equation 3. The drx-SlotOffset refers to the delay before the start of the drx-onDurationTimer 615. The drx-SlotOffset may be configured with, for example, time, number of slots, etc.

[0232] [(SFN x 10) + number of subframes] modulo (drx-ShortCycle) = (drx-StartOffset) modulo (drx-ShortCycle)

[0233] ...Equation 3

[0234] Among them, drx-ShortCycle and drx-StartOffset may be used to define a subframe to start a short DRX cycle 705. drx-ShortCycle and drx-StartOffset may be configured with, for example, time, number of subframes, number of time slots, etc.

[0235] So far, references have been Figure 6 and 7 DRX operation is described. In an embodiment of the present disclosure, the UE can reduce its power consumption by performing DRX operation. Although the UE performs DRX operation, the UE does not always receive the PDCCH related to the UE in the active time 605. Therefore, in an embodiment of the present disclosure, a signal for controlling the operation of the UE to more effectively save the power of the UE can be provided.

[0236] In the next generation mobile communication system (5G or NR system), in order to reduce the power consumption of UE, various transmission or reception related parameters can be controlled by layer 1 (L1) signaling. For example, L1 signaling with the purpose of reducing the power consumption of UE can control at least one parameter or parameter combination as shown in Table 14.

[0237] [Table 14]

[0238]

[0239]

[0240] Of course, this is not limited thereto, and various parameter information that may be included in L1 signaling transmitted in order to reduce power consumption will now be described.

[0241] In an embodiment of the present disclosure, L1 signaling sent to reduce power consumption may be referred to as a power saving signal (POSS). However, not limited thereto, POSS may also be referred to as various other terms, such as a power control signal, a power configuration signal, etc. For example, in an embodiment of the present disclosure, POSS may also be referred to as a wake-up signal (WUS), a power control signal, a DRX activation signal, a duration activation signal, a duration timer activation signal (drx-onDurationTimer Activation Signal), etc.

[0242] In addition, in an embodiment of the present disclosure, the UE can detect the DCI corresponding to the POSS by monitoring the PDCCH. In such a case, the DCI may be scrambled by a specific RNTI. The specific RNTI may be referred to as WUS-RNTI, PS-RNTI, POSS-RNTI, etc. In addition, the specific RNTI may be a newly defined RNTI or an existing RNTI may be used. The UE may receive the POSS based on the assumption that the POSS is scrambled by a specific RNTI. In such a case, the UE may descramble the POSS using a specific RNTI.

[0243] The POSS configuration method and the associated BS and UE operation methods will now be described according to the present disclosure. For example, the POSS configuration method and the associated BS and UE operation methods will be described in the case of applying a POSS monitoring method, a PDCCH monitoring method performed by a UE based on POSS, a POSS indication method, a POSS transmission method, an operation when POSS is not received, carrier aggregation (CA), BWP, etc. In an embodiment of the present disclosure, the power consumption of a UE for monitoring PDCCH can be minimized. In the present disclosure, specifically, a POSS configuration method and the associated BS and UE operation methods considering DRX operation will be described.

[0244] For ease of explanation, it is now assumed that POSS is WUS. However, it is not limited to this, and POSS can be referred to as many different terms as mentioned above.

[0245] Hereinafter, embodiments of the present disclosure are described in detail with reference to the accompanying drawings. Although the following embodiments of the present disclosure will take 5G systems as examples, they can be similarly applied to other communication systems with similar technical backgrounds or channel types. For example, other communication systems with similar technical backgrounds or channel types may include LTE or LTE-A mobile communication systems and any mobile communication technology developed after 5G. Therefore, the embodiments of the present disclosure will also be applied to other communication systems with some modifications, and the degree of modification will not significantly deviate from the scope of the present disclosure when judged by ordinary technicians in the field.

[0246] In the description of the present disclosure, when it is determined that the detailed description of the relevant function or configuration may unnecessarily obscure the subject matter of the present disclosure, the detailed description will be omitted. In addition, as described below, the terms are defined by considering the functions in the present disclosure, but may differ according to the practices or intentions of users or operators. Therefore, the terms should be defined according to the description in this specification.

[0247] Figure 8 is a diagram for describing WUS according to an embodiment of the present disclosure.

[0248] As described above, WUS is a signal to be sent in order to reduce the power consumption of UE. In an embodiment of the present disclosure, WUS may indicate whether UE is to wake up to monitor PDCCH. For example, WUS may indicate whether UE wakes up to monitor PDCCH at DRX time. In addition, WUS may be sent on PDCCH, and UE may detect DCI corresponding to WUS by monitoring PDCCH. In the present disclosure, UE may receive DCI corresponding to POSS detected by monitoring PDCCH. In such a case, DCI may be scrambled by a specific RNTI. Specific RNTI may be a newly defined RNTI or an existing RNTI may be used. UE may receive WUS based on the assumption that WUS is scrambled by a specific RNTI. In such a case, UE may descramble WUS using a specific RNTI. In an embodiment of the present disclosure, DCI may be UE-specific DCI or group common DCI. In the following description, for ease of explanation, the operation of receiving DCI corresponding to WUS by monitoring PDCCH is referred to as WUS monitoring operation. In addition, receiving WUS may be used as having the same meaning as receiving DCI with WUS.

[0249] refer to Figure 8 , when WUS monitoring operation is configured, the UE may receive WUS on the PDCCH in a time region configured for the UE to wake up at each DRX opportunity to monitor the PDCCH, i.e., a specific time region before the active time 605. The specific time region for receiving the WUS is referred to as a WUS opportunity 810. In an embodiment of the present disclosure, the WUS opportunity 810 may be located at least before the offset configured from the DRX opportunity, DRX duration, duration timer activation (drx-onDurationTimer Activation) of the time region for receiving or monitoring the PDCCH when the UE is in DRX operation, or the start point of the active time 605. The offset may be configured with a time, a number of time slots, or a number of subframes.

[0250] exist Figure 8 In the embodiment, WUS opportunity 810 is shown as being located in inactive time 610, which is a time when the UE does not need to monitor the PDCCH in DRX operation, that is, a time configured as the UE not receiving the PDCCH, but is not limited thereto. For example, WUS opportunity 810 may be located in active time 605. This will be described in detail later.

[0251] When the UE detects the WUS by monitoring the PDCCH in the WUS opportunity 810, the UE may or may not monitor the PDCCH in the time region configured as the active time 605 according to the content indicated by the WUS. For example, the UE may wake up at the DRX opportunity based on the indication of the WUS and monitor the PDCCH in the configured active time 605, or may not wake up when the DRX opportunity arrives, skip the configured active time 605, and remain in a sleep or inactive state in the inactive time 610.

[0252] In an embodiment of the present disclosure, the WUS may instruct the UE to wake up at the DRX timing associated with the WUS, the UE does not skip the DRX timing associated with the WUS, the UE will monitor the PDCCH at the DRX timing associated with the WUS, or start the drx-onDurationTimer 615 at the DRX timing associated with the WUS. Additionally or alternatively, the WUS may not instruct the UE to wake up at the DRX timing associated with the WUS, or may instruct the UE not to wake up at the DRX timing associated with the WUS, or may instruct the UE not to monitor the PDCCH at the DRX timing associated with the WUS, or may not start the drx-onDurationTimer 615 at the DRX timing associated with the WUS, or may instruct the UE to skip the drx timing associated with the WUS.

[0253] In an embodiment of the present disclosure, the length of the WUS opportunity 810 is shorter than the active time 605. Therefore, the time for turning on the receiver to receive and monitor the PDCCH on the WUS opportunity 810 is shorter than the time for turning on the receiver to receive and monitor the PDCCH in the active time 605. Therefore, the UE can reduce power consumption of the UE by monitoring the PDCCH when there is a PDCCH to be received based on the WUS.

[0254] Fig. 9 is a diagram for describing how to identify a WUS opportunity zone according to an embodiment of the present disclosure.

[0255] refer to Fig. 9 , the BS may indicate the WUS timing area to the UE. For example, the BS may provide the UE with WUS configuration information through high-layer signaling (RRC signaling, in the MIB or SIB). In an embodiment of the present disclosure, the WUS configuration information may include a WUS offset (WUS-Offset) or a WUS start offset (WUS-StartOffset) 910 and a WUS cycle 920. The BS may configure the WUS monitoring operation for the UE by sending the WUS configuration information. The UE may monitor the PDCCH based on the WUS configuration information provided by the BS to detect the DCI corresponding to the WUS.

[0256] Example 1-1

[0257] In embodiment 1-1 of the present disclosure, a method is provided in which a BS configures a WUS monitoring operation for a UE independently of a DRX operation.

[0258] In an embodiment of the present disclosure, the BS may configure a WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 and a WUS cycle 920 for the UE independently of the DRX timing, where the DRX timing is a time region in which the UE may receive or monitor the PDCCH. However, this means that the WUS may be configured independently of the DRX operation, and the parameters of the DRX configuration information may be used to represent the WUS configuration information. In an embodiment of the present disclosure, the WUS may be operated by considering the DRX operation or independently of the DRX operation, but in any case, the BS may configure the WUS timing for the UE independently of the DRX operation.

[0259] In an embodiment of the present disclosure, the BS may configure the UE with arbitrary values ​​of the WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 and the WUS cycle 920. The WUS cycle 920 may be configured with, for example, time, the number of subframes, the number of time slots, etc. In addition, the WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 may also be configured as time, the number of subframes, the number of time slots, etc. In addition, the WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 may have a negative value. In addition, the WUS offset may have an absolute value, i.e., relative to subframe 0, or a relative value relative to drx-StartOffset.

[0260] In an embodiment of the present disclosure, the BS may configure a WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 and a WUS cycle 920 for the UE, and configure a subframe or time slot satisfying Equation 4, Equation 4A, or Equation 4B as the location of the WUS opportunity. In addition, the BS may configure WUS-SlotOffset for the UE, and the WUS opportunity may be located in a time slot after WUS-SlotOffset of a subframe satisfying Equation 4, Equation 4A, or Equation 4B. WUS-SlotOffset refers to a delay before the start of WUS-onDurationTimer. drx-SlotOffset may be configured with time, number of time slots, etc.

[0261] [(SFN

[0262] …Equation 4

[0263] [(SFN

[0264] …Equation 4A

[0265] [(SFN

[0266] …Equation 4B

[0267] Among them, WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 and WUS cycle 920 can be configured as WUS-CycleStartOffset (or WUS-CycleOffset). In addition, WUS-CycleStartOffset (or WUS-CycleOffset) can be configured by, for example, time, number of subframes, number of time slots, etc.

[0268] In an embodiment of the present disclosure, a WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 may be configured based on a DRX timing, a DRX duration, a duration timer activation (drx-onDurationTimer activation), or an active time 605 of a time region in which the UE is able to receive or monitor a PDCCH. For example, the WUS timing may be configured to start before the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 from a starting point (e.g., a start symbol) of the DRX timing, the DRX duration, the duration timer activation (drx-onDurationTimer activation), or the active time 605. In such a case, the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 may also be configured with a time, a subframe number, a slot number, etc., and may have a negative value.

[0269] In an embodiment of the present disclosure, the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 may be configured based on the DRX cycle. The WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 may satisfy the following Equation 5.

[0270] WUS-Offset < DRX cycle (or drx-LongCycle) … Equation 5

[0271] As described above, the WUS occasion 810 may be located before the offset configured at least from the start point of the DRX occasion, DRX duration, drx-onDurationTimer Activation, or active time 605 of the time region for the UE to receive or monitor the PDCCH. Therefore, when the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 is configured based on the DRX cycle, the absolute value of the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 needs to be less than the DRX cycle (or drx-LongCycle).

[0272] In addition, the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 may satisfy Equation 6.

[0273] WUS-Offset (or WUS-StartOffset) = c * DRX cycle (or drx-LongCycle)

[0274] … Equation 6

[0275] (-1 < c < 1, where c is a rational number)

[0276] Among them, c can be a newly configured parameter, or can be created by combining existing parameters. The WUS opportunity 810 may be located before the offset configured from at least the DRX opportunity, DRX duration, duration timer activation (drx-onDurationTimer Activation) or the starting point of the active time 605 of the time area for the UE to receive or monitor the PDCCH. Therefore, the WUS offset (WUS-Offset) or WUS start offset (WUS-StartOffset) 910 needs to be less than the positive DRX cycle (or drx-LongCycle) and greater than the negative DRX cycle (or drx-LongCycle). In such a case, the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 can also be configured with time, the number of subframes, the number of time slots, etc., and can have a negative value.

[0277] In an embodiment of the present disclosure, the WUS cycle 920 may be N times (N is an integer) the DRX cycle. For example, the WUS cycle 920 may be N times (N is a natural number) the long DRX cycle 625.

[0278] Example 1-2

[0279] In embodiments 1-2 of the present disclosure, a method is provided in which a BS indicates a WUS timing to a UE considering DRX configuration information. For example, the BS may configure a WUS offset 910 and a WUS cycle 920 for a UE by considering a DRX timing, where the DRX timing is a time region in which the UE may receive or monitor a PDCCH. In addition, the WUS configuration information may be represented by parameters of the DRX configuration information. In an embodiment of the present disclosure, WUS may be operated by considering a DRX operation. The WUS cycle 920 may be configured with, for example, time, the number of subframes, the number of time slots, and the like. In addition, a WUS offset or a WUS start offset (WUS-Offset or WUS-StartOffset) 910 may also be configured with time, the number of subframes, the number of time slots, and the like.

[0280] In an embodiment of the present disclosure, the WUS cycle 920 may vary according to the length of the DRX cycle (or drx-LongCycle). For example, the WUS cycle 920 may be configured differently according to the result of comparing a preset value or a value configured by the BS with the length of the DRX cycle (or DRX long cycle). For example, when the preset value or the value configured by the BS is X, and the DRX cycle (or drx-LongCycle) is less than X, the WUS cycle 920 = N * DRX cycle (or drx-LongCycle), where N is a natural number. In such a case, according to the value of N, one WUS and multiple DRX opportunities are mapped to a pair of N (a pair of N mapping). In addition, when the preset value or the value configured by the BS is X, the DRX cycle (or drx-LongCycle) ≥ X, the WUS cycle 920 = DRX cycle (or drx-LongCycle). In such a case, one WUS and one DRX opportunity are mapped to a one-to-one (one-to-one mapping). Alternatively, when DRX cycle (or drx-LongCycle) ≥ X, WUS cycle 920 = K*DRX cycle (or drx-LongCycle), where K is a natural number. In this case, N and K may be different values ​​and may be indicated separately by the BS. The WUS cycle 920 and / or the DRX cycle (or DRX long cycle) may be configured with, for example, time, the number of subframes, the number of time slots, etc.

[0281] In addition, in an embodiment of the present disclosure, the WUS cycle 920 may be preset or defined according to the length of the DRX cycle (or drx-LongCycle). In this case, at least one or more DRX cycle (or drx-LongCycle) lengths and at least one or more WUS cycles 920 may be mapped and stored in the form of a table. In this case, it is not necessary to map the DRX cycle (or drx-LongCycle) length and the WUS cycle 920 one-to-one, and one or more WUS cycles 920 may be mapped to one DRX cycle (or drx-LongCycle) length, or in contrast, one WUS cycle 920 may be mapped to one or more DRX cycle (or drx-LongCycle) lengths. In an embodiment of the present disclosure, once the DRX cycle (or drx-LongCycle) is set, the WUS cycle 920 is also configured according to the table. The WUS cycle 920 and / or the DRX cycle (or drx-LongCycle) may be configured with, for example, time, the number of subframes, the number of time slots, etc.

[0282] In embodiments of the present disclosure, the WUS offset (WUS-Offset) or WUS start offset (WUS-StartOffset) 910 may be configured based on the DRX occasion, DRX duration, drx-onDurationTimer Activation, or active time 605 of the time region in which the UE can receive or monitor the PDCCH. For example, the WUS occasion may be configured to start before the WUS offset (WUS offset) or WUS start offset (WUSStartOffset) 910 from the start point (e.g., start symbol) of the DRX occasion, DRX duration, drx-onDurationTimer Activation, or active time 605. In such a case, the WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 may also be configured with a time, number of subframes, number of time slots, etc., and may have a negative value.

[0283] In embodiments of the present disclosure, the WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 may be configured based on the DRX cycle. The WUS offset or WUS start offset (WUS-offset or WUS-StartOffset) 910 may satisfy Equation 5.

[0284] WUS-Offset < DRX cycle (or drx-LongCycle) … Equation 5

[0285] As described above, the WUS occasion 810 may be located before the offset configured from the start point of at least the DRX occasion, DRX duration, drx-onDurationTimer Activation, or active time 605 of the time region in which the UE receives or monitors the PDCCH. Therefore, when the WUS offset (WUS-Offset) or WUS start offset (WUS-StartOffset) 910 is configured based on the DRX cycle, the absolute value of the WUS offset (WUS-Offset) or WUS start offset (WUS-StartOffset) 910 needs to be less than the DRX cycle (or drx-LongCycle).

[0286] In addition, the WUS offset or WUS start offset (US-offset or WUS-StartOffset) 910 may satisfy Equation 6.

[0287] WUS-Offset (or WUS-StartOffset) = c * DRX cycle (or drx-LongCycle)

[0288] ... Equation 6

[0289] (-1 < c < 1, where c is a rational number)

[0290] Wherein, c can be a newly configured parameter or can be created by combining existing parameters. In such a case, the WUS timing 810 can be located before the offset configured at the start point of at least the DRX timing, DRX duration, duration timer activation (drx-onDurationTimer Activation), or active time 605 of the time region for the UE to receive or monitor the PDCCH. Therefore, the WUS offset (WUS-Offset) or WUS start offset (WUS-StartOffset) 910 needs to be less than the positive DRX cycle (or drx-LongCycle) and greater than the negative DRX cycle (or drx-LongCycle). In such a case, the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 can also be configured with time, the number of subframes, the number of time slots, etc., and can have a negative value.

[0291] In an embodiment of the present disclosure, the WUS may include a BWP switching indicator that indicates switching to a specific BWP, BWP switching information, etc. In such a case, the BWP switching requires physical time. The time required for BWP switching can be referred to as the BWP switching delay T BWP_delay . Considering the BWP switching delay, the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 can also be configured to be greater than the BWP switching delay value. For example, the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 can be configured to be greater than the maximum BWP switching delay value.

[0292] As described above, in the next generation mobile communication system (5G or NR system), the BS may configure one or more BWPs for the UE. At least one of the configured one or more BWPs may be activated. For example, the BS may send a WUS in an activated BWP, and the WUS indicates whether to wake up to monitor the PDCCH in the CORESET of the inactive BWP. In such a case, a hardware and / or software process may be required to activate the deactivated BWP, and the process may cause delays. Therefore, in an embodiment of the present disclosure, considering the BWP switching delay, the BS may configure the WUS offset or WUS start offset (WUS-Offset or WUS-StartOffset) 910 to be greater than the BWP switching delay value.

[0293] Fig.10 is a diagram for describing how to monitor a PDCCH for WUS reception when a WUS opportunity is located in an active time according to an embodiment of the present disclosure.

[0294] refer to Fig.10 , when a specific event occurs in the active time 605 (e.g., receiving a PDCCH 630 indicating a new UL transmission or DL ​​transmission), the UE operating in the long DRX cycle starts or restarts the drx-InactivityTimer. In such a case, the UE may operate in the short DRX cycle, although Fig.10 Upon receiving the PDCCH 630 indicating a new UL transmission or DL ​​transmission, the UE may expect additional UL transmissions or DL ​​transmissions in the future and extend the active time 605 or delay the start of the inactive time 610.

[0295] In such a case, when the drx-InactivityTimer is continuously restarted due to continuous reception of a PDCCH indicating a new UL transmission or DL ​​transmission, the WUS opportunity 1010 may happen to be located in the active time 605 for different reasons (such as repeated extension of the active time 605 or delayed arrival of the inactive time 610). In an embodiment of the present disclosure, in order to reduce the power consumption of the UE, the UE wakes up from a sleep or inactive state during DRX operation and receives a WUS to determine whether there is a PDCCH to be received. However, when the WUS opportunity is located in the active time 605, the BS needs to determine whether to send the WUS because the UE is already awake and in an active state. In addition, the UE needs to determine whether to monitor the PDCCH to detect the DCI corresponding to the WUS.

[0296] Example 2-1

[0297] In Embodiment 2-1 of the present disclosure, a method of not monitoring the WUS when the WUS opportunity is in the active time 605 is provided.

[0298] In an embodiment of the present disclosure, when the WUS opportunity 1010 is located in the active time 605 due to various reasons such as repeated extension of the active time 605 or arrival delay of the inactive time 610, the BS may not send the WUS. In addition, the UE may not monitor the PDCCH to detect the DCI corresponding to the WUS. The UE does not need to monitor the PDCCH to detect the DCI corresponding to the WUS because the WUS is a signal to wake up the UE in the sleep or inactive state, but in such a case, the UE is already in the awake state.

[0299] In an embodiment of the present disclosure, a specific operation may be performed at a DRX timing associated with a WUS timing when the PDCCH is not monitored. The specific operation may include an operation that assumes that the WUS is always awake at the DRX timing, or a default operation. The default operation may be predefined or preset by the BS. The default operation may include an operation that is always awake. For example, Fig.10 In the example, the UE may perform an operation assuming that it always wakes up at the DRX opportunity 605-101 associated with the WUS opportunity 1010 located in the active time 605, or perform a default operation, such as waking up. In addition, although the WUS opportunity 1010 is shown as being associated with Fig.10 The UE may be related to one DRX opportunity 605-101, but is not limited thereto, and may be related to multiple DRX opportunities 605-101 and 605-102. In this case, the UE may perform an operation assuming wake-up at all multiple DRX opportunities 605-101 and 605-102, or a default operation, for example, an operation waking up.

[0300] Example 2-2

[0301] In Embodiment 2-2 of the present disclosure, a method of monitoring the WUS when the WUS opportunity is in the active time 605 will be described.

[0302] In an embodiment of the present disclosure, the BS may transmit the WUS even though the WUS opportunity 1010 is located in the active time 605 due to various reasons such as repeated extension of the active time 605 or arrival delay of the inactive time 610. In addition, the UE may monitor the PDCCH to detect the DCI corresponding to the WUS.

[0303] In an embodiment of the present disclosure, in the case where the WUS opportunity 1010 is located in the active time 605, when the result of detecting the DCI corresponding to the WUS by monitoring the PDCCH does not indicate that the UE will wake up at the DRX opportunity associated with the WUS, the UE will not wake up at the DRX opportunity associated with the WUS, the UE does not monitor the PDCCH at the DRX opportunity associated with the WUS, or does not start the drx-onDurationTimer 615, or the UE will skip the associated DRX opportunity, the UE can stop the active time 605. For example, the UE can stop the drx-onDurationTimer 615 and / or the drx-InactivityTimer 620. The UE can then enter a sleep or inactive state.

[0304] In addition, in an embodiment of the present disclosure, when the WUS opportunity 1010 is located in the active time 605, the DCI corresponding to the WUS may be arranged to have the same size as in the existing DCI format (eg, DCI format 0_0 / 1_0). Fig.11 to describe.

[0305] Fig.11 is a diagram for describing the format and size of DCI corresponding to a WUS according to an embodiment of the present disclosure.

[0306] In an embodiment of the present disclosure, the DCI corresponding to the WUS may have a size different from that of an existing DCI format (e.g., DCI format 0_0 / 1_0). The next generation mobile communication system (5G or NR system) may limit the number of DCIs with different sizes monitored by the UE at a specific time to a specific number or less to reduce the complexity of the DCI decoding of the UE. For example, the next generation mobile communication system (5G or NR system) may always meet the following two conditions:

[0307] Condition 1

[0308] - The UE may monitor up to X (eg, X=4) DCIs of different sizes in each slot.

[0309] Condition 2

[0310] - The UE may monitor up to Y DCIs of different sizes in each slot for a specific RNTI. For example, the specific RNTI may refer to C-RNTI, CS-RNTI, MCS-C-RNTI or any other UE-specific RNTI (eg, Y=3).

[0311] The BS may appropriately adjust the DCI size to satisfy conditions 1 and 2. The UE may not expect any configuration of the DCI size not to satisfy conditions 1 and 2. The size of the resource allocation field on the frequency axis of the DCI format 0_0 / 1_0 monitored in the UE-specific search space may be determined to have the size of the currently activated BWP. However, when the size of the DCI format 0_0 / 1_0 monitored in the UE-specific search space may be determined to have the size of the currently activated BWP and the restriction condition of the DCI size is not satisfied, the size of the resource allocation field on the frequency axis of the DCI format 0_0 / 1_0 may be determined to have the size of the initial BWP. Therefore, the size of the DCI format 0_0 / 1_0 monitored in the common search space is equal to the size of the DCI format 0_0 / 1_0 monitored in the UE-specific search space, thereby reducing the number of DCIs with different sizes.

[0312] WUS is usually transmitted in the inactive time 610, so no other DCI 1110 is transmitted at the same time. Therefore, the DCI corresponding to the WUS opportunity 810 transmitted in the inactive time 610 can be configured to have the same size as the format of other DCI 1110, or can be configured to ignore other DCI 1110. However, as Fig.10 As shown, when the WUS opportunity 1010 is located in the active time 605, the WUS is transmitted in the active time 605 and may be configured to have the same size as in the format (e.g., DCI format 0_0 / 1_0) of other DCI 1110 transmitted simultaneously. Even when conditions 1 and 2 are not satisfied, the WUS opportunity 810 may not be arranged to have the same size as in the format (e.g., DCI format 0_0 / 1_0) of other DCI 1110.

[0313] Alternatively, when conditions 1 and 2 are not satisfied, the WUS time 810 may be arranged to have the same size as in the format of other DCI 1110 (e.g., DCI format 0_0 / 1_0). In order to arrange the size of the DCI to be transmitted, when the DCI corresponding to the WUS time 810 is smaller than the format of other DCI 1110, zeros may be inserted (zero padding), and when the DCI corresponding to the WUS time 810 is larger than the format of other DCI 1110, bits of some fields may be eliminated (bit truncation).

[0314] In an embodiment of the present disclosure, by arranging the size of the DCI corresponding to the WUS opportunity 810, the number of blind decoding auxiliary numbers of the search space of the UE can be reduced, thereby resulting in power saving of the UE.

[0315] In addition, in an embodiment of the present disclosure, when the WUS timing is located at the active time 605, when the WUS indicates that the UE will wake up at the DRX timing, the UE can start the drx_ShortCycleTimer and operate in the short DRX cycle. The WUS indicating that the UE will wake up in the DRX timing means that there is data to be sent in the DRX timing, so the UE can immediately operate in the short DRX cycle.

[0316] In an embodiment of the present disclosure, the WUS may indicate the operation of the UE at a DRX opportunity related to the WUS. In order to indicate the operation of the UE at a DRX opportunity related to the WUS, a mapping method between the WUS and the DRX opportunity is required.

[0317] Example 3-1

[0318] In Embodiment 3-1 of the present disclosure, a method for performing one-to-one mapping between WUS and DRX is provided.

[0319] Fig.12 is a diagram for describing a method of performing one-to-one mapping between WUS and DRX according to an embodiment of the present disclosure.

[0320] refer to Fig.12 In an embodiment of the present disclosure, WUS 811, 812, and 813 are mapped one-to-one to respective DRX opportunities 605 (one-to-one mapping). For example, a WUS may indicate that the UE will wake up at a DRX opportunity associated with the WUS, and the UE will not skip the DRX opportunity associated with the WUS, the UE will monitor the PDCCH at the DRX opportunity associated with the WUS, or the UE will start the drx-onDurationTimer 615 at the DRX opportunity associated with the WUS.

[0321] In addition, WUS may not indicate that the UE will wake up at a DRX timing related to WUS, or may indicate that the UE will not wake up at a DRX timing related to WUS, the UE will not monitor PDCCH at a DRX timing related to WUS, or the UE will not start drx-onDurationTimer 615 at a DRX timing related to WUS, or may indicate that the UE will skip a DRX timing related to WUS.

[0322] In an embodiment of the present disclosure, when the WUSs 811 , 812 , and 813 are mapped one-to-one to the respective DRX opportunities 605 , the WUS cycle 920 may be the same as the DRX cycle (or drx-LongCycle).

[0323] Example 3-2

[0324] In Embodiment 3-2 of the present disclosure, a method for performing one-to-N mapping between WUS and DRX is provided.

[0325] Fig.13 is a diagram for describing a method of performing one-to-N mapping between WUS and DRX according to an embodiment of the present disclosure.

[0326] refer to Fig.13 In an embodiment of the present disclosure, one WUS opportunity 810 may be mapped to multiple DRX opportunities 605-1, 605-2, and 605-3 (a one-to-N mapping, where N is a natural number). For example, one WUS may indicate that the UE will wake up at multiple DRX opportunities associated with the WUS, the UE will not skip multiple DRX opportunities associated with the WUS, the UE will monitor the PDCCH at multiple DRX opportunities associated with the WUS, or the UE will start the drx-onDurationTimer615 at multiple DRX opportunities associated with the WUS.

[0327] In addition, WUS may not indicate that the UE will wake up in multiple DRX opportunities related to WUS, or may indicate that the UE will not wake up in multiple DRX opportunities related to WUS, or the UE will not monitor PDCCH in multiple DRX opportunities related to WUS, or the UE will not start drx-onDurationTimer 615 in multiple DRX opportunities related to WUS, or may indicate that the UE will skip multiple DRX opportunities related to WUS.

[0328] In an embodiment of the present disclosure, when one-to-N mapping is performed between one WUS opportunity 810 and multiple DRX opportunities 605, the multiple DRX opportunities 605-1, 605-2, and 605-3 may have the same indication on the multiple DRX opportunities 605-1, 605-2, and 605-3, or may have different indications on the respective DRX opportunities 605-1, 605-2, and 605-3. Fig.13 In the embodiment, one WUS opportunity 810 may indicate that the UE will wake up at all the multiple DRX opportunities 605-1, 605-2, and 605-3. In addition, one WUS opportunity 810 may indicate that the UE will wake up at DRX opportunity 605-1, the UE will skip the DRX opportunity at DRX opportunity 605-2, and the UE will wake up at DRX opportunity 605-3.

[0329] In the embodiments of the present disclosure, N is a preset value. For example, N may be a fixed value regarding the WUS monitoring operation in the communication system, or may be a value included in the WUS configuration information provided by the BS to the UE through high-layer signaling (e.g., RRC signaling, MIB or SIB).

[0330] In addition, in an embodiment of the present disclosure, N may be a value indicated by the WUS. In such a case, N may be expressed as a natural number or a bitmap format. For example, when there are three DRX opportunities after the WUS opportunity, the BS may indicate N in a bitmap format such as "101", indicating that the WUS indicates the operation at the first and third DRX opportunities. Alternatively, the BS may indicate N in a bitmap format such as "111", indicating that the WUS indicates the operation at the first, second, and third DRX opportunities.

[0331] In addition, in an embodiment of the present disclosure, N may be implicitly indicated by a WUS opportunity and a DRX opportunity. For example, the UE may monitor the PDCCH assuming that all DRX opportunities between two adjacent WUS opportunities are related to the WUS that is located in front in time. That is, a WUS received at a WUS opportunity may be mapped to all DRX opportunities before the next WUS opportunity after a WUS opportunity. For example, a WUS that is located in front in time may indicate waking up and monitoring the PDCCH in all DRX opportunities before the next WUS, indicating that it is not awakened in all DRX opportunities between two adjacent WUSs, or indicating waking up and monitoring the PDCCH in a configured DRX opportunity. For example, when there are 7 DRX opportunities between a first WUS opportunity that is located in front in time and a second WUS opportunity that is adjacent to or next to the first WUS opportunity, N=7. In such a case, the WUS received at the first WUS opportunity may be implicitly mapped to 7 DRX opportunities. In addition, the WUS received at the first WUS timing may indicate waking up in all DRX timings and monitoring PDCCH in 7 DRX timings until the second WUS timing, and the second WUS timing indicates not waking up in all DRX timings, or indicates waking up and monitoring PDCCH in the configured DRX timings. However, this is only an example and is not limited thereto, and N can be implicitly represented in various methods.

[0332] In addition, in an embodiment of the present disclosure, N may be indicated based on the time interval between adjacent WUS opportunities. For example, when the time interval between adjacent WUS opportunities is greater than or less than a specific value, N may be implicitly or explicitly configured.

[0333] In an embodiment of the present disclosure, the WUS may indicate the operation of the UE at a DRX opportunity related to the WUS. In such a case, the WUS may indicate with 1 bit whether the UE will wake up in all related DRX opportunities, and with N bits whether the UE will wake up in each related DRX opportunity. Alternatively, the WUS may provide additional information with K bits, for example, information about when the UE will wake up and whether the UE will wake up.

[0334] Example 4-1

[0335] In Embodiment 4-1 of the present disclosure, a method is provided in which a WUS indicates with 1 bit whether a UE is to wake up.

[0336] In an embodiment of the present disclosure, when indicating the operation of the UE at a DRX opportunity related to the WUS, the WUS may indicate whether the UE wakes up with only 1 bit. In an embodiment of the present disclosure, the overhead may be reduced by sending as little data as possible.

[0337] In addition, in an embodiment of the present disclosure, indicating whether the UE is to wake up may include indicating that the UE is to wake up at a DRX timing associated with WUS, indicating that the UE is not to skip a DRX timing associated with WUS, indicating that the UE is to monitor PDCCH at a DRX timing associated with WUS, or indicating that the UE is to start drx-onDurationTimer 615 at a DRX timing associated with WUS. Alternatively, indicating whether the UE is to wake up may include not indicating that the UE is to wake up at a DRX timing associated with WUS, indicating that the UE is not to wake up at a DRX timing associated with WUS, indicating that the UE is not to monitor PDCCH at a DRX timing associated with WUS, indicating that the UE is not to start drx-onDurationTimer 615 at a DRX timing associated with WUS, or indicating that the UE is to skip a DRX timing associated with WUS.

[0338] Fig.14 is a diagram for describing a method of performing one-to-N mapping between WUS and DRX according to an embodiment of the present disclosure, wherein WUS indicates whether a UE is to wake up with 1 bit.

[0339] In an embodiment of the present disclosure, when the WUS indicates whether the UE is to wake up with 1 bit and the WUS is mapped to N DRX opportunities, the WUS may give the indication in the form of a bitmap 1401. Fig.14 , the bitmap may include N bits, and each field 1410, 1420, 1430, ..., or N corresponding to each of the N bits may indicate whether the UE will wake up at the mapped DRX opportunity by "0" or "1".

[0340] Example 4-2

[0341] In embodiment 4-2 of the present disclosure, a method is provided in which the WUS provides additional information in the form of K bits, for example, information about when the UE wakes up in the active time 605 (ie, the wake-up time) and whether the UE is to wake up.

[0342] In an embodiment of the present disclosure, the size of the field indicating the additional information (i.e., the K value) may be indicated by the BS. The BS may provide the K value to the UE through high-layer signaling (RRC signaling in the MIB or SIB). In addition, the additional information may include information indicating when the UE wakes up in the active time 605, information indicating when the UE does not wake up, information related to changes in the WUS configuration (e.g., instructions to perform default operations), etc. In addition, in an embodiment of the present disclosure, indicating whether the UE is to wake up may include indicating that the UE is to wake up at a DRX opportunity related to the WUS, indicating that the UE does not skip the DRX opportunity related to the WUS, indicating that the UE is to monitor the PDCCH at a DRX opportunity related to the WUS, or indicating that the UE will start the drx-onDurationTimer615 at a DRX opportunity related to the WUS. Alternatively, instructing the UE whether to wake up may include not instructing the UE to wake up at a DRX timing related to WUS, instructing the UE not to wake up at a DRX timing related to WUS, instructing the UE not to monitor PDCCH at a DRX timing related to WUS, instructing the UE not to start drx-onDurationTimer 615 at a DRX timing related to WUS, or instructing the UE to skip a DRX timing related to WUS.

[0343] In the following description, for convenience of explanation, it is assumed that the additional information is information about when the UE wakes up in the active time 605. However, it is not limited thereto, and the additional information may include other various information.

[0344] In an embodiment of the present disclosure, a field having K bits may include both information about whether the UE is to wake up and information about when the UE wakes up in the active time 605. Fig.15 , will describe information about when the UE wakes up.

[0345] Fig.15 is a diagram for describing how a WUS indicates information about when a UE wakes up during active time according to an embodiment of the present disclosure.

[0346] refer to Fig.15 , the active time 605 is divided into 4 time zones, which can be indicated by 2 bits. For example, each time zone can be indicated by code points 00, 01, 10, and 11. In an embodiment of the present disclosure, the WUS opportunity 810 may include information about the time zone in which the UE is to wake up and information about whether the UE is to wake up. Fig.15 For example, WUS may include a total of 3 bits, of which 1 bit indicates information about whether the UE is to wake up, and 2 bits indicate information about the time zone in which the UE is to wake up. That is, K may be 3. In this case, the time zone may be each of the N DRX opportunities mapped to the WUS opportunity.

[0347] In an embodiment of the present disclosure described in conjunction with embodiment 4-2 of the present disclosure, information about whether the UE will be awakened and information about when the UE will be awakened during the active time 605 may be separated and included in different fields in the WUS. In such a case, as in embodiment 3-2 of the present disclosure, each field may indicate an operation regarding multiple DRX opportunities mapped to the WUS. In addition, in an embodiment of the present disclosure, each field may be represented by a bitmap. For example, when the WUS is mapped to 5 DRX opportunities (N=5), it may be indicated in a 5-bit bitmap whether the UE will be awakened in the corresponding DRX opportunity. In addition, additional information, such as information about when the UE wakes up during the active time 605, may also be indicated in a K-bit bitmap.

[0348] In an embodiment of the present disclosure, the interpretation of the area indicated by the bitmap may vary according to the relationship between the N value indicating how many DRX opportunities the WUS is mapped to and the K value indicating the size of the additional information. For example, when N=5 and K=3, some of the K bits may indicate information about 2 DRX opportunities according to the upper limit (N / K)=2, and the remaining K bits may indicate information about one DRX opportunity according to the lower limit (N / K)=1.

[0349] In an embodiment of the present disclosure, a WUS may be sent for one or more UEs. For example, the WUS may include PDCCH monitoring configuration information of one or more UEs. That is, the WUS may be sent in units of multiple UEs.

[0350] In an embodiment of the present disclosure, the BS may send a WUS through a common search space (CSS), and the PDCCH monitoring configuration information of multiple UEs may be included in one WUS. For example, one WUS may include a scaling factor for a PDCCH monitoring cycle for each UE. In addition, the cell to which the PDCCH monitoring configuration information is mapped may be identified based on the bit position in the WUS.

[0351] When WUS indicates whether UE is to wake up in only 1 bit, the overhead can be reduced, but it is difficult to transmit a large amount of information. In an embodiment of the present disclosure, the WUS monitoring operation can be more finely controlled by extending the size of the data transmitted in WUS to K bits and transmitting additional information at the same time.

[0352] Fig.16 is a diagram for describing the relationship between a WUS monitoring operation and short DRX according to an embodiment of the present disclosure.

[0353] refer to Fig.16, when a specific event occurs in the active time 605 (e.g., receiving a PDCCH 630 indicating a new UL transmission or DL ​​transmission), the UE operating in the long DRX cycle can operate in the short DRX cycle 705. The short DRX cycle can be selectively applied. For example, the UE starts the drx-ShortCycleTimer when the previous drx-onDurationTimer or drx-InactivityTimer expires, and operates in the short drx cycle until the drx-ShortCycleTimer expires. Thereafter, when the drx-ShortCycleTimer expires, the UE operates in the long DRX cycle again.

[0354] The relationship between the short DRX cycle operation and the WUS monitoring operation needs to be determined.

[0355] Example 5-1

[0356] In Embodiment 5-1 of the present disclosure, in a case where both the short DRX cycle operation and the WUS monitoring operation are configured, a method of performing any one of the short DRX cycle operation or the WUS monitoring operation is provided.

[0357] In an embodiment of the present disclosure, the short DRX cycle operation and the WUS monitoring operation cannot be configured for the UE at the same time. When one operation is configured first, the UE may not be configured with the other operation despite receiving configuration information from the BS, or may ignore the configuration information.

[0358] Alternatively, in an embodiment of the present disclosure, when the UE is configured with a short DRX cycle operation and a WUS monitoring operation at the same time, the UE may determine that one of the two operations is released. For example, when the UE is configured with a short DRX cycle operation and a WUS monitoring operation at the same time, the UE may only perform the short DRX cycle operation or only perform the WUS monitoring operation. In such a case, one of the operations may be released in the time sequence when the short DRX cycle operation and the WUS monitoring operation are configured. For example, the UE may perform an operation configured later after releasing the previously configured operation, or may only perform the previously configured operation when releasing the later configured operation.

[0359] In an embodiment of the present disclosure, a WUS monitoring operation may be performed only for a long DRX cycle, but may not be performed when a short DRX cycle operation is configured. For example, when a drx-ShortCycleTimer is running, the UE may not perform a WUS monitoring operation.

[0360] Example 5-2

[0361] In Embodiment 5-2 of the present disclosure, in a case where both the short DRX cycle operation and the WUS monitoring operation are configured, a method of not performing the WUS monitoring operation is provided.

[0362] In an embodiment of the present disclosure, when the UE operates in a short DRX cycle, the UE may not perform a WUS monitoring operation. For example, when the drx-ShortCycleTimer is running, the UE may not wake up at the WUS timing. For example, the UE may not monitor the PDCCH to detect the DCI corresponding to the WUS at the WUS timing. Afterwards, when the drx-ShortCycleTimer stops or the drx-ShortCycleTimer expires, the UE may resume the WUS monitoring operation. In addition, in an embodiment of the present disclosure, when the UE operates in a long DRX cycle, the UE may resume the WUS monitoring operation. Resuming the WUS monitoring operation performed by the UE means that the UE wakes up at the WUS timing and monitors the PDCCH to detect the DCI corresponding to the WUS.

[0363] In an embodiment of the present disclosure, when the UE operates in a short DRX cycle, the UE may always wake up and monitor the PDCCH at the DRX timing. As described above, since the UE may not know whether data transmission is scheduled at the DRX timing corresponding to the WUS timing unless the WUS monitoring operation is not performed when operating in the short DRX cycle, the UE may always wake up and monitor the PDCCH at the DRX timing to receive data. In addition, although the UE operates in the long DRX cycle again after operating in the short DRX cycle, the UE may always wake up and monitor the PDCCH at the DRX timing corresponding to the WUS timing where no PDCCH is monitored in order to detect the DCI corresponding to the WUS.

[0364] Example 5-3

[0365] In Embodiment 5-3 of the present disclosure, in a case where both the short DRX cycle operation and the WUS monitoring operation are configured, a method of performing both the short DRX cycle operation and the WUS monitoring operation is provided.

[0366] In an embodiment of the present disclosure, the new WUS configuration information can be used to apply the WUS monitoring operation during the short DRX cycle operation. In such a case, the WUS monitoring operation performed in the long DRX cycle is referred to as long-WUS (long WUS), and the WUS monitoring operation performed in the short DRX cycle is referred to as short-WUS (short WUS). The long WUS and the short WUS can be configured to have different WUS offsets and WUS cycles. In an embodiment of the present disclosure, the BS can start a short-duration timer for the UE similar to the long WUS. For example, the BS can provide the short WUS configuration information for the UE through higher-layer signaling (e.g., RRC signaling, in the MIB or SIB). In addition, for the short WUS operation, the DCI corresponding to the short WUS can have a DCI format different from that of the DCI corresponding to the long WUS. In such a case, the DCI corresponding to the short WUS can be scrambled by an RNTI different from the RNTI of the DCI corresponding to the long WUS. In addition, the DCI corresponding to the short WUS can be transmitted in a control resource set different from the control resource set (i.e., a different CORESET) for transmitting the DCI corresponding to the long WUS. In addition, the DCI corresponding to the long WUS can be transmitted in a search space different from the search space for transmitting the DCI corresponding to the short WUS.

[0367] In an embodiment of the present disclosure, the short WUS cycle can vary according to the length of the short DRX cycle. For example, the short WUS cycle can be configured differently based on the result of comparing a preset value or a value configured by the BS with the drx-ShortCycleTimer value. The drx-ShortCycleTimer value can be M*drx-ShortCycle, where M is a natural number. For example, when the preset value or the value configured by the BS is X, and the drx-ShortCycleTimer value is less than X (<X), the short WUS cycle = N*drx-ShortCycle, where N is a natural number. In such a case, according to the value of N, one WUS and multiple DRX opportunities are mapped in a one-to-N mapping (one-to-N mapping). In such a case, the short WUS cycle and / or the drx-ShortCycle can be configured with, for example, time, the number of subframes, the number of time slots, etc.

[0368] In an embodiment of the present disclosure, N is a preset value. For example, N can be a fixed value for the short WUS monitoring operation in the communication system, or can be a value included in the short WUS configuration information provided by the BS to the UE through higher-layer signaling (e.g., RRC signaling, in the MIB or SIB).

[0369] In addition, in an embodiment of the present disclosure, N may be a value indicated by a short WUS. In such a case, N may be expressed as a natural number or a bitmap format. For example, when there are three DRX opportunities after a short WUS opportunity, the BS may indicate N in a bitmap format such as "101", indicating that the short WUS indicates operation at the first and third DRX opportunities. Alternatively, the BS may indicate N in a bitmap format such as "111", indicating that the short WUS indicates operation at the first, second, and third DRX opportunities.

[0370] In addition, in the embodiments of the present disclosure, N may be implicitly indicated by the short WUS opportunity and the DRX opportunity. For example, the UE may wake up and monitor the PDCCH in all DRX opportunities between two adjacent short WUS opportunities.

[0371] In addition, in an embodiment of the present disclosure, when the preset value or the value configured by the BS is X, drx-ShortCycle≥X, short WUS cycle=drx-ShortCycle. In this case, one WUS and one DRX opportunity are mapped one-to-one (one-to-one mapping). In this case, the short WUS cycle and / or drx-ShortCycle may be configured with, for example, time, the number of subframes, the number of time slots, etc.

[0372] In an embodiment of the present disclosure, while operating in a short DRX cycle, the UE can fully apply the WUS monitoring operation based on the existing WUS configuration information. In such a case, when the WUS indicates that the UE will wake up at the DRX opportunity or when no WUS is received, the UE can maintain the short DRX cycle and perform short DRX cycle operations. In addition, when the WUS does not indicate that the UE will wake up at the DRX opportunity, the UE may not subsequently start the duration timer (drx-onDurationTimer). In addition, the UE can stop the drx-ShortCycleTimer and then operate in a long DRX cycle. The WUS indicating that the UE will wake up at the DRX opportunity means that there is no data to be sent at the DRX opportunity, so the UE can operate immediately in the long DRX cycle.

[0373] In an embodiment of the present disclosure, a WUS cycle may refer to a cycle in which WUS opportunities occur. Therefore, the UE needs to wake up in each WUS cycle and monitor the PDCCH based on the WUS configuration information provided by the BS. In contrast, the BS does not need to always send a WUS in a WUS cycle. The BS may send a WUS only when there is information to be sent, or may send a WUS in each WUS cycle. Therefore, it is necessary to determine how to send a WUS based on a WUS cycle.

[0374] Example 6-1

[0375] In Embodiment 6-1 of the present disclosure, a method for sending a WUS when the UE needs to wake up or when there is a change is provided.

[0376] In an embodiment of the present disclosure, the UE needs to always wake up in the WUS cycle and monitor the PDCCH based on the WUS configuration information provided by the BS, but the BS can send the WUS only when there is information to be sent. For example, the BS can send the WUS only when the UE needs to wake up or there is a change. For example, when the UE receives a WUS mapped to multiple DRX opportunities and operates according to the instructions of the received WUS, the change may refer to configuring different operations at the DRX opportunities mapped to the WUS. For example, it may refer to when data to be sent at a specific time appears before arriving at a specific time, so the UE needs to wake up, although the WUS indicates that the UE is not to wake up at the DRX opportunity at the specific time.

[0377] In an embodiment of the present disclosure, when monitoring PDCCH but no DCI corresponding to WUS is detected when receiving WUS, the UE may perform an operation according to the indication of the previously received WUS or perform a default operation. The default operation may be predefined or preset by the BS. The default operation may include an operation of always waking up. In addition, in an embodiment of the present disclosure, when the UE does not receive a WUS for a period of time or longer, the UE may perform a default operation. The specific period may be predefined or set by the BS.

[0378] Example 6-2

[0379] In Embodiment 6-2 of the present disclosure, a method of always sending a WUS in a WUS cycle is provided.

[0380] In an embodiment of the present disclosure, the BS may wake up and send a WUS to the UE in each WUS cycle. In this case, the WUS may provide a 1-bit indication of whether the UE is to wake up, and additional information, such as information about when the UE is to wake up and whether the UE is to wake up, in K bits.

[0381] In an embodiment of the present disclosure, when PDCCH is monitored but no DCI corresponding to WUS is detected at the time of receiving WUS (i.e., in the WUS cycle), the UE may perform an operation according to the indication of the previously received WUS or perform a default operation. The default operation may be predefined or set by the BS. The default operation may include an operation of always waking up. In addition, in an embodiment of the present disclosure, the UE may skip the DRX opportunity associated with the unreceived WUS.

[0382] In an embodiment of the present disclosure, although carrier aggregation (CA) or BWP is configured, WUS monitoring operation can be applied. For example, WUS can be transmitted in each cell or each cell group and in each BWP or a specific BWP. Now, a cell group in which WUS is transmitted when CA or BWP is configured will be described.

[0383] Example 7-1

[0384] In Embodiment 7-1 of the present disclosure, a method of transmitting a WUS in each cell group including a plurality of cells is provided.

[0385] In an embodiment of the present disclosure, a WUS may be transmitted in each cell group including a plurality of cells. For example, one WUS corresponding to a plurality of cells may be transmitted, and the UE may receive the WUS corresponding to the plurality of cells by monitoring one CORESET or search area.

[0386] Fig.17 is a diagram for describing how to transmit a WUS to each cell group including a plurality of cells according to an embodiment of the present disclosure.

[0387] For example, the WUS may be sent in a primary cell (PCell) and a primary cell (PSCell) of two cell groups, a primary cell group (MCG) and a secondary cell group (SCG), respectively, and the WUS sent in each cell group may control the PDCCH monitoring operation of the cells in the cell group.

[0388] refer to Fig.17, one WUS opportunity 810 may be sent in the PCell or PSCell (serving cell #0) 1710. One WUS opportunity 810 may control the PDCCH monitoring configuration in the serving cell #0 1710, the serving cell #1 1720, and the serving cell #2 1730. For example, the WUS opportunity 810 sent in the PCell or PSCell (i.e., the serving cell #0 1710) may be used to indicate that the UE will wake up at the DRX opportunity associated with the WUS opportunity 810 of the serving cell #0 1710, the serving cell #1 1720, and the serving cell #2 1730, the UE will not skip the DRX opportunity associated with the WUS opportunity 810, the UE will monitor the PDCCH at the DRX opportunity associated with the WUS opportunity 810, or the UE will start the Drx-onDurationTimer 615 at the DRX opportunity associated with the WUS opportunity 810. Alternatively, the WUS timing 810 may not instruct the UE to wake up at the DRX timing associated with the WUS timing 810, or may instruct the UE not to wake up at the DRX timing associated with the WUS timing 810, or may instruct the UE not to monitor the PDCCH at the DRX timing associated with the WUS timing 810, or the UE may not start the drx-onDurationTimer 615 at the DRX timing associated with the WUS timing 810, or may instruct the UE to skip the DRX timing associated with the WUS timing 810.

[0389] In an embodiment of the present disclosure, a WUS opportunity 810 may include a cross-carrier indicator to indicate a cell for controlling the PDCCH monitoring configuration. Alternatively, the cell for controlling the PDCCH monitoring configuration may be indicated in a cross-carrier indicator field (CIF). The PDCCH monitoring configuration in a WUS opportunity 810 is generally applicable to all cells. In an embodiment of the present disclosure, when a cross-carrier indicator or CIF is configured, a WUS may be sent in a cell using the cross-carrier indicator or CIF to control the PDCCH monitoring configuration of other cells. When a P(S) cell, i.e., serving cell #0 1710, uses a cross-carrier indicator or CIF to control the PDCCH monitoring configuration of serving cell #1 1720, the WUS may be sent in the P(S) cell, i.e., serving cell #0 1710.

[0390] In an embodiment of the present disclosure, a WUS opportunity 810 may include both PDCCH monitoring configuration information and WUS configuration information for multiple cells. For example, PDCCH monitoring configuration information or WUS configuration information for a cell configured for CA or a cell activated by CA may be provided in a format indicating a cell index in the WUS time 810. For example, the WUS configuration 810 may include a parameter indicating or determining a cell index to which the PDCCH monitoring configuration information or WUS configuration information is applied. The PDCCH monitoring configuration information or WUS configuration information may be applied to a cell having a cell index indicated or determined by a parameter included in the WUS opportunity 810. In an embodiment of the present disclosure, when a WUS opportunity 810 includes PDCCH monitoring configuration information or WUS configuration information for multiple cells, the cell to which the PDCCH monitoring configuration information or WUS configuration information is mapped may be identified based on the bit position in the WUS opportunity 810. To this end, the BS may configure the UE with the position of the bit to control each cell in the WUS opportunity 810 through high-level signaling (e.g., RRC signaling). The UE can know which cell each bit in the received WUS opportunity 810 controls based on the PDCCH monitoring configuration information or the WUS configuration information received from the BS, and accordingly, control the WUS-based PDCCH monitoring of multiple cells (for example, refer to the aforementioned WUS-related functions, such as whether to monitor the PDCCH at the DRX opportunity related to the WUS). In addition, a WUS opportunity 810 can include a scaling factor of the PDCCH monitoring cycle in the cell index order.

[0391] In addition, the BS may configure a BWP in which one WUS is transmitted for a plurality of cells. The BS may configure a BWP in which one WUS for a plurality of cells is received using an identifier of the BWP.

[0392] Example 7-2

[0393] In Embodiment 7-2 of the present disclosure, a method of sending a WUS in each cell is provided.

[0394] In an embodiment of the present disclosure, a WUS may be sent in each cell. For example, a WUS corresponding to each cell may be sent, and the UE may receive the WUS corresponding to the cell by monitoring the CORESET or search area of ​​the cell.

[0395] Fig.18 is a diagram for describing how to send a WUS in each cell according to an embodiment of the present disclosure;

[0396] refer to Fig.18, the first WUS 811 may be sent in a PCell or a PSCell (i.e., serving cell #0 1810) to control the PDCCH monitoring configuration in the PCell or the PSCell. The second WUS 812 may be sent in serving cell #2 1830 to control the PDCCH monitoring configuration in serving cell #2 1830. For example, the WUSs 811 and 812 sent in the corresponding cells 1810 and 1830 may be used to indicate that the UE will wake up at the DRX timing associated with the WUSs 811 and 812 of the cells 1810 and 1830, the UE will not skip the DRX timing associated with the WUSs 811 and 812, the UE will monitor the PDCCH at the DRX timing associated with the WUSs 811 and 812, or the UE will start the drx-onDurationTimer 615 at the DRX timing associated with the WUSs 811 and 812. Alternatively, WUS 811 and 812 may not indicate that the UE will wake up at the DRX timing associated with WUS811 and 812, or may indicate that the UE will not wake up at the DRX timing associated with WUS 811 and 812, that the UE will not monitor PDCCH at the DRX timing associated with WUS 811 and 812, or that the UE will not start Drx-onDurationTimer 615 at the DRX timing associated with WUS 811 and 812, or may instruct the UE to skip the DRX timing associated with WUS 811 and 812.

[0397] When cross-carrier scheduling is configured, the BS can use the cross-carrier indicator to control the PDCCH monitoring configuration of other cells. Fig.18 , when cross-carrier scheduling is configured, the UE may control the PDCCH monitoring configuration in the serving cell #1 1820 based on the cross-carrier indicator or CIF and the first WUS 811 sent in the serving cell #0 1810. In other words, when the cross-carrier indicator or CIF is configured, the cross-carrier indicator or CIF may be used to send a WUS in a cell to control the PDCCH monitoring configuration of other cells. The WUS configured by the cross-carrier scheduling for controlling a cell (referred to as the second cell) may be transmitted in a cell (referred to as the first cell) that also schedules the second cell. For example, when the P(S) cell, i.e., the serving cell #0 1810, controls the PDCCH monitoring configuration of the serving cell #1 1820 using the cross-carrier indicator or CIF, the WUS 811 may be sent from the P(S) cell, i.e., the serving cell #0 1810.

[0398] When cross-carrier scheduling is configured, WUS 811 may include both PDCCH monitoring configuration information and WUS configuration information of multiple cells controlled by WUS 811, as in the case where one WUS 811 as described above includes both PDCCH monitoring configuration information and WUS configuration information controlled by WUS 811. For example, PDCCH monitoring configuration information or WUS configuration information of multiple cells may be provided in WUS 811 in a format indicating a cell index. For example, WUS 811 may include a parameter indicating or determining an index of a cell to which the PDCCH monitoring configuration information or WUS configuration information is applied. The PDCCH monitoring configuration information or WUS configuration information may be applied to a cell having a cell index indicated or determined by a parameter included in WUS 811. In an embodiment of the present disclosure, when one WUS 811 includes PDCCH monitoring configuration information or WUS configuration information of multiple cells, the cell to which the PDCCH monitoring configuration information or WUS configuration information is mapped may be identified based on the bit position in WUS 811. To this end, the BS can use the position of the bit to configure the UE to control each cell in the WUS opportunity 810 through high-layer signaling (e.g., RRC signaling). The UE can know which cell each bit in the received WUS opportunity 810 controls based on the configuration information received from the BS, and accordingly control the WUS based on PDCCH monitoring (e.g., refer to the aforementioned WUS-related functions, such as whether to monitor PDCCH at a DRX opportunity related to WUS) of multiple cells. In addition, a WUS 811 can include a scaling factor of the PDCCH monitoring cycle in the cell index order.

[0399] When sending WUS in each cell, the WUS offset in each cell may be different. For example, the BS may configure the WUS offset for each cell separately, or configure an additional offset for each cell. In addition, the WUS cycle in each cell may also be different.

[0400] In addition, the BWP in which the WUS is transmitted in each cell may be the same or different. In an embodiment of the present disclosure, the BS may configure the BWP in which the WUS is transmitted using an identifier of the BWP.

[0401] Example 7-3

[0402] In Embodiment 7-3 of the present disclosure, a method of sending a WUS in each BWP is provided.

[0403] In an embodiment of the present disclosure, when multiple BWPs are configured, a WUS may be sent in an activated BWP. For example, a WUS corresponding to each BWP may be sent, and the UE may receive the WUS corresponding to the BWP by monitoring the CORESET or search area of ​​the BWP.

[0404] In an embodiment of the present disclosure, when multiple BWPs are configured, a WUS may be sent in a specific BWP for WUS transmission, such as a wake-up BWP. The wake-up BWP may be distinguished from other BWPs and may have an appropriate configuration for waking up the PDCCH, including, for example, waking up the CORESET and waking up the search space configuration. In an embodiment of the present disclosure, a BWP switching indicator or BWP switching information may be used as a trigger for a WUS monitoring operation. For example, when the UE performs a BWP switching based on a BWP switching indicator or BWP switching information while monitoring a BWP that is not configured with a WUS, a WUS monitoring operation may be started when the BWP to be switched is configured with a WUS. In an embodiment of the present disclosure, when the UE operates in a BWP in which a WUS is not sent, the BS may send an explicit indication for the UE to check for a WUS. In addition, in an embodiment of the present disclosure, when the UE operates in a BWP in which no WUS is sent, when DRX is applied and an inactive time occurs due to, for example, the expiration of a duration timer, the UE may switch to a BWP in which a WUS is sent.

[0405] In an embodiment of the present disclosure, one WUS opportunity 810 may include PDCCH monitoring configuration information for multiple BWPs. For example, PDCCH monitoring configuration information or WUS configuration information for multiple BWPs may be provided in a format indicating a BWP index in the WUS opportunity 810. For example, the WUS opportunity 810 may include a parameter indicating or determining the index of the BWP to which the PDCCH monitoring configuration information or WUS configuration information is applied. The PDCCH monitoring configuration information or WUS configuration information may be applied to a cell of a BWP index indicated or determined by a parameter included in the WUS opportunity 810. In an embodiment of the present disclosure, when one WUS opportunity 810 includes PDCCH monitoring configuration information or WUS configuration information for multiple cells, the BWP to which the PDCCH monitoring configuration information or WUS configuration information is mapped may be identified based on the bit position in the WUS opportunity 810. In addition, one WUS opportunity 810 may include a scaling factor for the PDCCH monitoring cycle in the BWP index order.

[0406] The above-mentioned embodiments of the present disclosure may be used in combination.

[0407] Fig.19 is a sequence diagram illustrating a method for power saving of a UE in a mobile communication system according to an embodiment of the present disclosure.

[0408] refer to Fig.19In operation 1910, BS 1901 sends WUS configuration information to UE 1902. BS 1901 can configure WUS monitoring operation for UE by sending WUS configuration information. In an embodiment of the present disclosure, BS 1901 can provide WUS configuration information to UE 1902 through high-layer signaling (e.g., RRC signaling, in MIB or SIB). In an embodiment of the present disclosure, WUS configuration information may include WUS offset or WUS start offset and WUS cycle.

[0409] In an embodiment of the present disclosure, the BS 1901 may configure the WUS monitoring operation for the UE 1902 independently, regardless of the DRX operation, or by considering the DRX configuration information.

[0410] In operation 1920, the UE 1902 may monitor the PDCCH based on the WUS configuration information. For example, the UE 1902 may monitor the PDCCH at a WUS timing, which is a specific time region for receiving a WUS based on the WUS configuration information.

[0411] In an embodiment of the present disclosure, when the WUS timing is located in the active time, the UE 1902 may not monitor the WUS, but may perform a specific operation at a DRX timing associated with the WUS timing where no PDCCH is monitored. Alternatively, when the WUS timing is located in the active time, the UE 1902 may monitor the WUS, and when the WUS indicates that the UE 1902 will not wake up at the DRX timing associated with the WUS, the UE 1902 may stop the active time 605. When the WUS indicates that the UE 1902 will wake up at the DRX timing associated with the WUS, the DCI corresponding to the WUS may be arranged to have the same size as in the existing DCI format (e.g., DCI format 0_0 / 1_0).

[0412] In operation 1930, the UE 1902 may receive a WUS on the downlink control channel PDCCH from the BS 1901. For example, while monitoring the downlink control channel PDCCH based on the WUS configuration information, the UE 1902 may receive the WUS when the WUS is transmitted.

[0413] In the embodiments of the present disclosure, the WUS and the DRX occasions may be mapped one-to-one or one-to-N. N may be preset, may be a value indicated by the WUS, or may be implicitly set.

[0414] In an embodiment of the present disclosure, the WUS may indicate whether the UE is to wake up with 1 bit, or provide additional information with K bits, for example, information about when the UE wakes up in the active time 605 (ie, the wake-up time), and whether the UE is to wake up.

[0415] In an embodiment of the present disclosure, UE 1902 needs to wake up in each WUS cycle and monitor PDCCH based on WUS configuration information provided by BS. In contrast, BS1901 does not always need to send WUS in the WUS cycle. In an embodiment of the present disclosure, when WUS is sent only when there is information to be sent, but the DCI corresponding to WUS is not detected when receiving WUS, although PDCCH is monitored, UE 1902 can operate or perform default operation according to the indication of the previously received WUS. In addition, when UE 1902 does not receive WUS for a certain period of time or longer, UE can perform default operation. In an embodiment of the present disclosure, when WUS is sent in each WUS cycle, UE 1902 can operate according to the indication of the previously received WUS, or perform default operation. In addition, in an embodiment of the present disclosure, UE 1902 can skip the DRX opportunity associated with the unreceived WUS.

[0416] In operation 1940, the UE 1902 may wake up at a DRX timing associated with the WUS based WUS.

[0417] In an embodiment of the present disclosure, when both the short DRX cycle operation and the WUS monitoring operation are configured, one of the short DRX cycle operation and the WUS monitoring operation may be performed; when both the short DRX cycle operation and the WUS monitoring operation are configured, the WUS monitoring operation may not be performed; when both the short DRX cycle operation and the WUS monitoring operation are configured, both the short DRX cycle operation and the WUS monitoring operation may be performed.

[0418] In an embodiment of the present disclosure, although CA or BWP is configured, a WUS monitoring operation may be applied.In an embodiment of the present disclosure, a WUS may be transmitted for each cell group including a plurality of cells, for each cell, or in each BWP.

[0419] Fig. 20 is a flowchart illustrating an operation of a UE performing a method for saving power of the UE in a wireless communication system according to an embodiment of the present disclosure;

[0420] refer to Fig. 20 In operation 2010, the BS sends WUS configuration information to the UE. In an embodiment of the present disclosure, the UE may receive the WUS configuration information from the BS through high-layer signaling (e.g., RRC signaling, MIB or SIB). In an embodiment of the present disclosure, the WUS configuration information may include a WUS offset or a WUS start offset and a WUS cycle.

[0421] In operation 220, the UE may monitor the DL control channel (PDCCH) based on the WUS configuration information. For example, the UE may monitor the DL control channel (PDCCH) at a WUS timing, which is a specific time region for receiving a WUS based on the WUS configuration information.

[0422] In an embodiment of the present disclosure, when the WUS timing is in the active time, the UE may not monitor the WUS, but may perform specific operations at the DRX timing associated with the WUS timing where no PDCCH is monitored. Alternatively, when the WUS timing is in the active time, the UE may monitor the WUS, and when the WUS indicates that the UE will not wake up at the DRX timing associated with the WUS, the UE may stop the active time. When the WUS indicates that the UE will wake up at the DRX timing associated with the WUS, the DCI corresponding to the WUS may be arranged to have the same size as in the existing DCI format (e.g., DCI format 0_0 / 1_0).

[0423] In operation 2030, the UE receives a WUS from the BS on a DL control channel. For example, in operation 2020, the UE 1902 may receive a WUS when the WUS is transmitted while monitoring the DL control channel PDCCH based on the WUS configuration information.

[0424] In the embodiments of the present disclosure, the WUS and the DRX occasions may be mapped one-to-one or one-to-N. N may be preset, may be a value indicated by the WUS, or may be implicitly set.

[0425] In an embodiment of the present disclosure, the WUS may indicate whether the UE is to wake up with 1 bit, or provide additional information with K bits, for example, information about when the UE wakes up during the active time (ie, the wake-up time), and whether the UE wakes up.

[0426] In an embodiment of the present disclosure, when a WUS is sent only when there is information to be sent, but the DCI corresponding to the WUS is not detected when the WUS is received, although the PDCCH is monitored, the UE can operate according to the indication of the previously received WUS or perform a default operation. In addition, when the UE does not receive a WUS for a certain period of time or longer, the UE can perform a default operation. In an embodiment of the present disclosure, when a WUS is sent in each WUS cycle, the UE can operate according to the indication of the previously received WUS, or perform a default operation. In addition, in an embodiment of the present disclosure, the UE can skip the DRX opportunity associated with the unreceived WUS.

[0427] In operation 2040, the UE may wake up at a DRX timing related to the WUS based on the WUS.

[0428] In an embodiment of the present disclosure, when both the short DRX cycle operation and the WUS monitoring operation are configured, one of the short DRX cycle operation and the WUS monitoring operation may be performed. When both the short DRX cycle operation and the WUS monitoring operation are configured, the WUS monitoring operation may not be performed. When both the short DRX cycle operation and the WUS monitoring operation are configured, both the short DRX cycle operation and the WUS monitoring operation may be performed.

[0429] In an embodiment of the present disclosure, although CA or BWP is configured, a WUS monitoring operation may be applied.In an embodiment of the present disclosure, a WUS may be transmitted for each cell group including a plurality of cells, for each cell, or in each BWP.

[0430] Fig.21 is a flowchart illustrating an operation of a BS performing a method of saving power of a UE in a wireless communication system according to an embodiment of the present disclosure.

[0431] refer to Fig.21 In operation 2110, the BS sends WUS configuration information to the UE. The BS may configure the WUS monitoring operation for the UE by sending the WUS configuration information. In an embodiment of the present disclosure, the BS may provide the UE with the WUS configuration information through high-layer signaling (e.g., RRC signaling, in the MIB or SIB). In an embodiment of the present disclosure, the WUS configuration information may include a WUS offset or a WUS start offset and a WUS cycle.

[0432] In an embodiment of the present disclosure, the BS may configure a WUS monitoring operation for the UE independently regardless of the DRX operation or by considering the DRX configuration information.

[0433] In operation 2120, the BS transmits a WUS to the UE on a DL control channel (PDCCH).

[0434] In an embodiment of the present disclosure, when the WUS timing is located in active time and the WUS indicates that the UE will wake up at the DRX timing related to the WUS, the BS can arrange the DCI corresponding to the WUS to have the same size as in the existing DCI format (e.g., DCI format 0_0 / 1_0).

[0435] In the embodiments of the present disclosure, the WUS and the DRX occasions may be mapped one-to-one or one-to-N. N may be preset, may be a value indicated by the WUS, or may be implicitly set.

[0436] In an embodiment of the present disclosure, the WUS may indicate whether the UE is to wake up with 1 bit, or provide additional information with K bits, for example, information about when the UE wakes up during the active time (ie, the wake-up time), and whether the UE wakes up.

[0437] In operation 2130, the BS transmits control information to the UE on a DL control channel based on the WUS.

[0438] In an embodiment of the present disclosure, when both the short DRX cycle operation and the WUS monitoring operation are configured, one of the short DRX cycle operation and the WUS monitoring operation may be performed; when both the short DRX cycle operation and the WUS monitoring operation are configured, the WUS monitoring operation may not be performed; when both the short DRX cycle operation and the WUS monitoring operation are configured, both the short DRX cycle operation and the WUS monitoring operation may be performed.

[0439] In an embodiment of the present disclosure, although CA or BWP is configured, a WUS monitoring operation may be applied.In an embodiment of the present disclosure, a WUS may be transmitted for each cell group including a plurality of cells, for each cell, or in each BWP.

[0440] Fig. 22 and Fig.23 The transceiver, memory and processor of the UE and BS for implementing the embodiments of the present disclosure are shown in the figure. The embodiments of the present disclosure provide a POSS transmission and reception method, a PDCCH monitoring control method and a transmission and reception method of the BS and UE to which the data transmission and reception operations according to the method are applied. In order to perform these methods, the transceiver, memory and processor of the UE and BS can be operated according to the aforementioned embodiments of the present disclosure.

[0441] Fig. 22 is a block diagram showing the structure of a UE according to an embodiment of the present disclosure.

[0442] refer to Fig. 22 , the UE may include a transceiver 2210, a memory 2220, and a processor 2230. However, the components of the UE are not limited thereto. For example, the UE may include more or fewer elements than those described above. In addition, at least part or all of the transceiver 2210, the memory 2220, and the processor 2230 may be implemented in a single chip.

[0443] In an embodiment of the present disclosure, the transceiver 2210 may send a signal to a BS or receive a signal from a BS. The above-mentioned signal may include control information and data. To this end, the transceiver 2210 may include an RF transmitter for up-converting the frequency of the signal to be sent and amplifying the signal and an RF receiver for low-noise amplifying the received signal and down-converting the frequency of the received signal. In addition, the transceiver 2210 may receive a signal on a wireless channel and output the signal to the processor 2230, or send a signal output from the processor 2230 on a wireless channel.

[0444] In an embodiment of the present disclosure, the memory 2220 may store programs and data required for UE operation. In addition, the memory 2220 may store control information or data included in a signal sent or received by the UE. The memory 2220 may include a storage medium or a combination of storage media such as a read-only memory (ROM), a random access memory (RAM), a hard disk, a compact disk (CD) ROM, and a digital versatile disk (DVD). In addition, the memory 2220 may be in plural form. In an embodiment of the present disclosure, the memory 2220 may store a program for performing an operation for saving power of the UE.

[0445] In an embodiment of the present disclosure, the processor 2230 may control a series of processes of the UE to be operated according to the above-mentioned embodiment of the present disclosure. In an embodiment of the present disclosure, the processor 2230 may execute a program stored in the memory 2220 to control the UE to receive WUS configuration information from the BS, monitor the DL control channel (PDCCH) based on the WUS configuration information, receive WUS from the BS on the DL control channel, and wake up.

[0446] Fig.23 is a block diagram showing the structure of a BS according to an embodiment of the present disclosure.

[0447] refer to Fig.23 , the BS may include a transceiver 2310, a memory 2320, and a processor 2330. However, the components of the BS are not limited thereto. For example, the BS may include more or fewer elements than those described above. In addition, the transceiver 2310, the memory 2320, and the processor 2330 may be implemented in a single chip.

[0448] In an embodiment of the present disclosure, the transceiver 2310 may send a signal to or receive a signal from the UE. The above-mentioned signal may include control information and data. To this end, the transceiver 2310 may include an RF transmitter for up-converting the frequency of the signal to be sent and amplifying the signal and an RF receiver for low-noise amplifying the received signal and down-converting the frequency of the received signal. In addition, the transceiver 2310 may receive a signal on a wireless channel and output the signal to the processor 2330, or send a signal output from the processor 2330 on a wireless channel.

[0449] In an embodiment of the present disclosure, the memory 2320 may store programs and data required for BS operation. In addition, the memory 2320 may store control information or data included in a signal sent or received by the BS. The memory 2320 may include a storage medium such as ROM, RAM, hard disk, CD-ROM and DVD or a combination of storage media. In addition, the memory 2320 may be in plural form. In an embodiment of the present disclosure, the memory 2320 may store a program for performing an operation for saving power of the UE.

[0450] In an embodiment of the present disclosure, the processor 2330 may control a series of processes of the BS to be operated according to the above-mentioned embodiment of the present disclosure. In an embodiment of the present disclosure, the processor 2330 may execute a program stored in the memory 2320 to control the BS to send WUS configuration information to the UE, send WUS to the UE on a DL control channel based on the WUS configuration information, and send control information to the UE on a DL control channel based on the WUS.

[0451] The methods according to the embodiments described in the claims or the specification of the present disclosure may be implemented in hardware, software, or a combination of hardware and software.

[0452] When implemented in software, a computer-readable storage medium or a computer program product storing one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium or a computer program product are configured to be executed by one or more processors in an electronic device. One or more programs may include instructions for causing an electronic device to perform a method according to an embodiment described in the claims or specification of the present disclosure.

[0453] The program (software module, software) may be stored in RAM, non-volatile memory including flash memory, ROM, electrically erasable programmable ROM (EEPROM), magnetic disk storage, CD-ROM, DVD or other type of optical storage device and / or cassette tape. Alternatively, the program may be stored in a memory that includes a combination of some or all of the programs. There may be multiple memories.

[0454] The program may also be stored in a connectable storage device that may be accessed through a communication network including the Internet, an intranet, a local area network (LAN), a wide area network (WLAN), or a storage area network (SAN), or a combination thereof. The storage device may be connected to the device executing the embodiments of the present disclosure through an external port. In addition, an additional storage device in the communication network may access the device executing the embodiments of the present disclosure.

[0455] Embodiments of the present disclosure may provide a communication method and device for effectively saving power of a UE in a mobile communication system.

[0456] Although the present disclosure has been shown and described with reference to various embodiments of the present disclosure, it will be understood by those skilled in the art that various changes may be made to the form and details of the present disclosure without departing from the spirit and scope of the present disclosure as defined by the attached claims and their equivalents. Therefore, it is apparent to those of ordinary skill in the art that the present disclosure is not limited to the embodiments of the present disclosure provided for illustrative purposes only. In addition, the embodiments may be operated by mutual combination when necessary. For example, one embodiment of the present disclosure and some of another embodiment of the present disclosure may be combined to operate a BS and a UE. The embodiments of the present disclosure may be similarly applied to other communication systems, and other modifications may also be made to the embodiments without departing from the scope of the present disclosure. For example, the embodiments of the present disclosure may also be applied to LTE systems, 5G or NR systems, etc.

Claims

1. A method performed by a user equipment UE in a wireless communication system, the method comprising: receiving configuration information associated with power saving information from a base station; Identifying whether power saving information monitoring is configured in case a long discontinuous reception (DRX) cycle is used; In case power saving information monitoring is configured, based on the power saving related indication, starting the drx duration timer; as well as In case the short DRX cycle is used, the drx duration timer is started.

2. The method according to claim 1, further comprising: The Physical Downlink Control Channel PDCCH is monitored during active time.

3. The method according to claim 1, wherein: In case the short DRX cycle is used, monitoring of the power saving information is not performed.

4. The method according to claim 3, further comprising: In the event that the drx short cycle timer stops or expires, monitoring of the power saving information is resumed.

5. The method according to claim 1, wherein: The configuration information is included in a Radio Resource Control, RRC, message.

6. The method according to claim 1, wherein: The configuration information includes offset information of the power saving information.

7. The method according to claim 1, further comprising: In case power saving information monitoring is configured and no power saving related indication is recognized, the drx duration timer is started.

8. A user equipment UE in a wireless communication system, the UE comprising: Transceiver; as well as At least one processor is coupled to the transceiver and is configured to: receiving configuration information associated with power saving information from a base station; Identifying whether power saving information monitoring is configured in case a long discontinuous reception (DRX) cycle is used; In case power saving information monitoring is configured, based on the power saving related indication, starting the drx duration timer; as well as In case the short DRX cycle is used, the drx duration timer is started.

9. The UE according to claim 8, wherein: The at least one processor is further configured to: The Physical Downlink Control Channel PDCCH is monitored during active time.

10. The UE according to claim 8, wherein: In case the short DRX cycle is used, monitoring of the power saving information is not performed.

11. The UE according to claim 10, wherein: The at least one processor is further configured to: In the event that the drx short cycle timer stops or expires, monitoring of the power saving information is resumed.

12. The UE according to claim 8, wherein: The configuration information is included in a Radio Resource Control, RRC, message.

13. The UE according to claim 8, wherein: The configuration information includes offset information of the power saving information.

14. The UE according to claim 8, wherein: The at least one processor is further configured to: In case power saving information monitoring is configured and no power saving related indication is recognized, the drx duration timer is started.

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