Patent ID: 12200772

DESCRIPTION OF EXEMPLARY EMBODIMENTS

FIG.1illustrates a communication system1applied to the present specification.

Referring toFIG.1, a communication system1applied to the present specification includes wireless devices, Base Stations (BSs), and a network. Herein, the wireless devices represent devices performing communication using Radio Access Technology (RAT) (e.g., 5G New RAT (NR)) or Long-Term Evolution (LTE)) and may be referred to as communication/radio/5G devices. The wireless devices may include, without being limited to, a robot100a, vehicles100b-1and100b-2, an eXtended Reality (XR) device100c, a hand-held device100d, a home appliance100e, an Internet of Things (IoT) device100f, and an Artificial Intelligence (AI) device/server400. For example, the vehicles may include a vehicle having a wireless communication function, an autonomous vehicle, and a vehicle capable of performing communication between vehicles. Herein, the vehicles may include an Unmanned Aerial Vehicle (UAV) (e.g., a drone). The XR device may include an Augmented Reality (AR)/Virtual Reality (VR)/Mixed Reality (MR) device and may be implemented in the form of a Head-Mounted Device (HMD), a Head-Up Display (HUD) mounted in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance device, a digital signage, a vehicle, a robot, etc. The hand-held device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or a smartglasses), and a computer (e.g., a notebook). The home appliance may include a TV, a refrigerator, and a washing machine. The IoT device may include a sensor and a smartmeter. For example, the BSs and the network may be implemented as wireless devices and a specific wireless device200amay operate as a BS/network node with respect to other wireless devices.

The wireless devices100ato100fmay be connected to the network300via the BSs200. An AI technology may be applied to the wireless devices100ato100fand the wireless devices100ato100fmay be connected to the AI server400via the network300. The network300may be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although the wireless devices100ato100fmay communicate with each other through the BSs200/network300, the wireless devices100ato100fmay perform direct communication (e.g., sidelink communication) with each other without passing through the BSs/network. For example, the vehicles100b-1and100b-2may perform direct communication (e.g. Vehicle-to-Vehicle (V2V)/Vehicle-to-everything (V2X) communication). In addition, the IoT device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices100ato100f.

Wireless communication/connections150a,150b, or150cmay be established between the wireless devices100ato100f/BS200, or BS200/BS200. Herein, the wireless communication/connections may be established through various RATs (e.g., 5G NR) such as uplink/downlink communication150a, sidelink communication150b(or, D2D communication), or inter BS communication (e.g. relay, Integrated Access Backhaul(IAB)). The wireless devices and the BSs/the wireless devices may transmit/receive radio signals to/from each other through the wireless communication/connections150aand150b. For example, the wireless communication/connections150aand150bmay transmit/receive signals through various physical channels. To this end, at least a part of various configuration information configuring processes, various signal processing processes (e.g., channel encoding/decoding, modulation/demodulation, and resource mapping/demapping), and resource allocating processes, for transmitting/receiving radio signals, may be performed based on the various proposals of the present disclosure.

Here, the wireless communication technology implemented in the wireless devices100and200of the present specification may include a narrowband Internet of Things for low-power communication as well as LTE, NR, and 6G. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and it may be implemented in standards such as LTE Cat NB1 and/or LTE Cat NB2, and is not limited to the above-described name. Additionally or alternatively, the wireless communication technology implemented in the wireless devices100and200of the present specification may perform communication based on the LTE-M technology. In this case, as an example, the LTE-M technology may be an example of an LPWAN technology, and may be called by various names such as enhanced machine type communication (eMTC). For example, LTE-M technology may be implemented in at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and/or 7) LTE M, and is not limited to the above-described name. Additionally or alternatively, the wireless communication technology implemented in the wireless devices100and200of the present specification may include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) in consideration of low power communication, and is not limited to the above-mentioned names. For example, the ZigBee technology can create PAN (personal area networks) related to small/low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

FIG.2illustrates a wireless device applicable to this specification.

Referring toFIG.2, the first wireless device100and the second wireless device200may transmit/receive wireless signals through various wireless access technologies (e.g., LTE, NR).

The first wireless device100includes at least one processor102and at least one memory104and may further include at least one transceiver106and/or at least one antenna108. The processor102may be configured to control the memory104and/or the transceiver106and to implement the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein. For example, the processor102may process information in the memory104to generate first information/signal and may then transmit a radio signal including the first information/signal through the transceiver106. In addition, the processor102may receive a radio signal including second information/signal through the transceiver106and may store information obtained from signal processing of the second information/signal in the memory104. The memory104may be connected to the processor102and may store various pieces of information related to the operation of the processor102. For example, the memory104may store a software code including instructions to perform some or all of processes controlled by the processor102or to perform the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein. Here, the processor102and the memory104may be part of a communication modem/circuit/chip designed to implement a radio communication technology (e.g., LTE or NR). The transceiver106may be connected with the processor102and may transmit and/or receive a radio signal via the at least one antennas108. The transceiver106may include a transmitter and/or a receiver. The transceiver106may be replaced with a radio frequency (RF) unit. In this specification, the wireless device may refer to a communication modem/circuit/chip.

The second wireless device200includes at least one processor202and at least one memory204and may further include at least one transceiver206and/or at least one antenna208. The processor202may be configured to control the memory204and/or the transceiver206and to implement the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein. For example, the processor202may process information in the memory204to generate third information/signal and may then transmit a radio signal including the third information/signal through the transceiver206. In addition, the processor202may receive a radio signal including fourth information/signal through the transceiver206and may store information obtained from signal processing of the fourth information/signal in the memory204. The memory204may be connected to the processor202and may store various pieces of information related to the operation of the processor202. For example, the memory204may store a software code including instructions to perform some or all of processes controlled by the processor202or to perform the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein. Here, the processor202and the memory204may be part of a communication modem/circuit/chip designed to implement a radio communication technology (e.g., LTE or NR). The transceiver206may be connected with the processor202and may transmit and/or receive a radio signal via the at least one antennas208. The transceiver206may include a transmitter and/or a receiver. The transceiver206may be replaced with an RF unit. In this specification, the wireless device may refer to a communication modem/circuit/chip.

Hereinafter, hardware elements of the wireless devices100and200are described in detail. At least one protocol layer may be implemented, but limited to, by the at least one processor102and202. For example, the at least one processor102and202may implement at least one layer (e.g., a functional layer, such as PHY, MAC, RLC, PDCP, RRC, and SDAP layers). The at least one processor102and202may generate at least one protocol data unit (PDU) and/or at least one service data unit (SDU) according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein. The at least one processor102and202may generate a message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein. The at least one processor102and202may generate a signal (e.g., a baseband signal) including a PDU, an SDU, a message, control information, data, or information according to the functions, procedures, proposals, and/or methods disclosed herein and may provide the signal to the at least one transceiver106and206. The at least one processor102and202may receive a signal (e.g., a baseband signal) from the at least one transceiver106and206and may obtain a PDU, an SDU, a message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein.

The at least one processor102and202may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The at least one processor102and202may be implemented by hardware, firmware, software, or a combination thereof. For example, at least one application-specific integrated circuit (ASIC), at least one digital signal processor (DSP), at least one digital signal processing devices (DSPD), at least one programmable logic devices (PLD), or at least one field programmable gate array (FPGA) may be included in the at least one processor102and202. The one or more processors102and202may be implemented as at least one computer readable medium (CRM) including instructions based on being executed by the at least one processor.

For example, each method described inFIGS.26to30may be performed by at least one computer readable medium (CRM) including instructions based on being executed by at least one processor. The CRM, for example, may access the base station through a random access procedure. After that, the CRM may perform receiving downlink control information (DCI) including information for a change to a value of K0min or K2 min in a slot n of a scheduling cell, each of the K0min and K2 min being an applied minimum scheduling offset restriction, and applying a changed K0min or a changed K2 min value in a slot n+X of the scheduling cell. The X value is a largest value among i) a first value obtained by multiplying currently applied K0min (Y) in a scheduled cell scheduled by the DCI by 2μscheduling/2μscheduledand then performing ceiling and ii) a second value (Z) that are predetermined depending on a subcarrier spacing (SCS) of the scheduling cell. The μscheduling is a subcarrier spacing configuration of the scheduling cell and the μscheduled is a subcarrier spacing configuration of the scheduled cell.

The descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein may be implemented using firmware or software, and the firmware or software may be configured to include modules, procedures, functions, and the like. The firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein may be included in the at least one processor102and202or may be stored in the at least one memory104and204and may be executed by the at least one processor102and202. The descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein may be implemented in the form of a code, an instruction, and/or a set of instructions using firmware or software.

The at least one memory104and204may be connected to the at least one processor102and202and may store various forms of data, signals, messages, information, programs, codes, indications, and/or commands. The at least one memory104and204may be configured as a ROM, a RAM, an EPROM, a flash memory, a hard drive, a register, a cache memory, a computer-readable storage medium, and/or a combinations thereof. The at least one memory104and204may be disposed inside and/or outside the at least one processor102and202. In addition, the at least one memory104and204may be connected to the at least one processor102and202through various techniques, such as a wired or wireless connection.

The at least one transceiver106and206may transmit user data, control information, a radio signal/channel, or the like mentioned in the methods and/or operational flowcharts disclosed herein to at least different device. The at least one transceiver106and206may receive user data, control information, a radio signal/channel, or the like mentioned in the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein from at least one different device. For example, the at least one transceiver106and206may be connected to the at least one processor102and202and may transmit and receive a radio signal. For example, the at least one processor102and202may control the at least one transceiver106and206to transmit user data, control information, or a radio signal to at least one different device. In addition, the at least one processor102and202may control the at least one transceiver106and206to receive user data, control information, or a radio signal from at least one different device. The at least one transceiver106and206may be connected to the at least one antenna108and208and may be configured to transmit or receive user data, control information, a radio signal/channel, or the like mentioned in the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein through the at least one antenna108and208. In this document, the at least one antenna may be a plurality of physical antennas or may be a plurality of logical antennas (e.g., antenna ports). The at least one transceiver106and206may convert a received radio signal/channel from an RF band signal into a baseband signal in order to process received user data, control information, a radio signal/channel, or the like using the at least one processor102and202. The at least one transceiver106and206may convert user data, control information, a radio signal/channel, or the like, processed using the at least one processor102and202, from a baseband signal to an RF bad signal. To this end, the at least one transceiver106and206may include an (analog) oscillator and/or a filter.

FIG.3shows an example of a structure of a signal processing module. Here, the signal processing may be performed by the processors102and202ofFIG.2.

Referring toFIG.3, the transmitting device (e.g., a processor, the processor and a memory, or the processor and a transceiver) in a UE or BS may include a scrambler301, a modulator302, a layer mapper303, an antenna port mapper304, a resource block mapper305, and a signal generator306.

The transmitting device can transmit one or more codewords. Coded bits in each codeword are scrambled by the corresponding scrambler301and transmitted over a physical channel. A codeword may be referred to as a data string and may be equivalent to a transport block which is a data block provided by the MAC layer.

Scrambled bits are modulated into complex-valued modulation symbols by the corresponding modulator302. The modulator302can modulate the scrambled bits according to a modulation scheme to arrange complex-valued modulation symbols representing positions on a signal constellation. The modulation scheme is not limited and m-PSK (m-Phase Shift Keying) or m-QAM (m-Quadrature Amplitude Modulation) may be used to modulate the coded data. The modulator may be referred to as a modulation mapper.

The complex-valued modulation symbols can be mapped to one or more transport layers by the layer mapper303. Complex-valued modulation symbols on each layer can be mapped by the antenna port mapper304for transmission on an antenna port.

Each resource block mapper305can map complex-valued modulation symbols with respect to each antenna port to appropriate resource elements in a virtual resource block allocated for transmission. The resource block mapper can map the virtual resource block to a physical resource block according to an appropriate mapping scheme. The resource block mapper305can allocate complex-valued modulation symbols with respect to each antenna port to appropriate subcarriers and multiplex the complex-valued modulation symbols according to a user.

Signal generator306can modulate complex-valued modulation symbols with respect to each antenna port, that is, antenna-specific symbols, according to a specific modulation scheme, for example, OFDM (Orthogonal Frequency Division Multiplexing), to generate a complex-valued time domain OFDM symbol signal. The signal generator can perform IFFT (Inverse Fast Fourier Transform) on the antenna-specific symbols, and a CP (cyclic Prefix) can be inserted into time domain symbols on which IFFT has been performed. OFDM symbols are subjected to digital-analog conversion and frequency up-conversion and then transmitted to the receiving device through each transmission antenna. The signal generator may include an IFFT module, a CP inserting unit, a digital-to-analog converter (DAC) and a frequency upconverter.

FIG.4shows another example of a structure of a signal processing module in a transmitting device. Herein, signal processing may be performed in a processor of a UEBS, such as the processors102and202ofFIG.2.

Referring toFIG.4, the transmitting device (e.g., a processor, the processor and a memory, or the processor and a transceiver) in the UE or the BS may include a scrambler401, a modulator402, a layer mapper403, a precoder404, a resource block mapper405, and a signal generator406.

The transmitting device can scramble coded bits in a codeword by the corresponding scrambler401and then transmit the scrambled coded bits through a physical channel.

Scrambled bits are modulated into complex-valued modulation symbols by the corresponding modulator402. The modulator can modulate the scrambled bits according to a predetermined modulation scheme to arrange complex-valued modulation symbols representing positions on a signal constellation. The modulation scheme is not limited and pi/2-BPSK (pi/2-Binary Phase Shift Keying), m-PSK (m-Phase Shift Keying) or m-QAM (m-Quadrature Amplitude Modulation) may be used to modulate the coded data.

The complex-valued modulation symbols can be mapped to one or more transport layers by the layer mapper403.

Complex-valued modulation symbols on each layer can be precoded by the precoder404for transmission on an antenna port. Here, the precoder may perform transform precoding on the complex-valued modulation symbols and then perform precoding. Alternatively, the precoder may perform precoding without performing transform precoding. The precoder404can process the complex-valued modulation symbols according to MIMO using multiple transmission antennas to output antenna-specific symbols and distribute the antenna-specific symbols to the corresponding resource block mapper405. An output z of the precoder404can be obtained by multiplying an output y of the layer mapper403by an N×M precoding matrix W. Here, N is the number of antenna ports and M is the number of layers.

Each resource block mapper405maps complex-valued modulation symbols with respect to each antenna port to appropriate resource elements in a virtual resource block allocated for transmission.

The resource block mapper405can allocate complex-valued modulation symbols to appropriate subcarriers and multiplex the complex-valued modulation symbols according to a user.

Signal generator406can modulate complex-valued modulation symbols according to a specific modulation scheme, for example, OFDM, to generate a complex-valued time domain OFDM symbol signal. The signal generator406can perform IFFT (Inverse Fast Fourier Transform) on antenna-specific symbols, and a CP (cyclic Prefix) can be inserted into time domain symbols on which IFFT has been performed. OFDM symbols are subjected to digital-analog conversion and frequency up-conversion and then transmitted to the receiving device through each transmission antenna. The signal generator406may include an IFFT module, a CP inserting unit, a digital-to-analog converter (DAC) and a frequency upconverter.

The signal processing procedure of the receiving device may be reverse to the signal processing procedure of the transmitting device. Specifically, the processor of the transmitting device decodes and demodulates RF signals received through antenna ports of the transceiver. The receiving device may include a plurality of reception antennas, and signals received through the reception antennas are restored to baseband signals, and then multiplexed and demodulated according to MIMO to be restored to a data string intended to be transmitted by the transmitting device. The receiving device may include a signal restoration unit that restores received signals to baseband signals, a multiplexer for combining and multiplexing received signals, and a channel demodulator for demodulating multiplexed signal strings into corresponding codewords. The signal restoration unit, the multiplexer and the channel demodulator may be configured as an integrated module or independent modules for executing functions thereof. More specifically, the signal restoration unit may include an analog-to-digital converter (ADC) for converting an analog signal into a digital signal, a CP removal unit that removes a CP from the digital signal, an FET module for applying FFT (fast Fourier transform) to the signal from which the CP has been removed to output frequency domain symbols, and a resource element demapper/equalizer for restoring the frequency domain symbols to antenna-specific symbols. The antenna-specific symbols are restored to transport layers by the multiplexer and the transport layers are restored by the channel demodulator to codewords intended to be transmitted by the transmitting device.

FIG.5illustrates an example of a wireless communication device according to an implementation example of the present disclosure.

Referring toFIG.5, the wireless communication device, for example, a UE may include at least one of a processor2310such as a digital signal processor (DSP) or a microprocessor, a transceiver2335, a power management module2305, an antenna2340, a battery2355, a display2315, a keypad2320, a global positioning system (GPS) chip2360, a sensor2365, a memory2330, a subscriber identification module (SIM) card2325, a speaker2345and a microphone2350. A plurality of antennas and a plurality of processors may be provided.

The processor2310can implement functions, procedures and methods described in the present description. The processor2310inFIG.5may be the processors102and202inFIG.2.

The memory2330is connected to the processor2310and stores information related to operations of the processor. The memory may be located inside or outside the processor and connected to the processor through various techniques such as wired connection and wireless connection. The memory2330inFIG.5may be the memories104and204inFIG.2.

A user can input various types of information such as telephone numbers using various techniques such as pressing buttons of the keypad2320or activating sound using the microphone2350. The processor2310can receive and process user information and execute an appropriate function such as calling using an input telephone number. In some scenarios, data can be retrieved from the SIM card2325or the memory2330to execute appropriate functions. In some scenarios, the processor2310can display various types of information and data on the display2315for user convenience.

The transceiver2335is connected to the processor2310and transmit and/or receive RF signals. The processor can control the transceiver in order to start communication or to transmit RF signals including various types of information or data such as voice communication data. The transceiver includes a transmitter and a receiver for transmitting and receiving RF signals. The antenna2340can facilitate transmission and reception of RF signals. In some implementation examples, when the transceiver receives an RF signal, the transceiver can forward and convert the signal into a baseband frequency for processing performed by the processor. The signal can be processed through various techniques such as converting into audible or readable information to be output through the speaker2345. The transceiver inFIG.5may be the transceivers106and206inFIG.2.

Although not shown inFIG.5, various components such as a camera and a universal serial bus (USB) port may be additionally included in the UE. For example, the camera may be connected to the processor2310.

FIG.5is an example of implementation with respect to the UE and implementation examples of the present disclosure are not limited thereto. The UE need not essentially include all the components shown inFIG.5. That is, some of the components, for example, the keypad2320, the GPS chip2360, the sensor2365and the SIM card2325may not be essential components. In this case, they may not be included in the UE.

FIG.6shows an example of a processor2000.

Referring toFIG.6, the processor2000may include a control channel monitoring unit2010and a data channel receiving unit2020. The processor2000may execute the methods (the position of the receiver, for example, the position of the UE) described with reference toFIGS.26to30. For example, the processor2000may access the base station through a random access procedure. After that, the processor2000receives downlink control information (DCI) including information notifying a change in the value of K0 min or K2 min in slot n of a scheduling cell, each of K0min and K2 min being an applied minimum scheduling offset restriction. Also, the processor2000applies the changed K0min or the changed K2 min value in the slot n+X of the scheduling cell. The X value is a largest value among i) a first value obtained by multiplying currently applied K0min (Y) in a scheduled cell scheduled by the DCI by 2μscheduling/2μscheduledand then performing ceiling and ii) a second value (Z) that are predetermined depending on a subcarrier spacing (SCS) of the scheduling cell. The μscheduling is a subcarrier spacing configuration of the scheduling cell and the μscheduled is a subcarrier spacing configuration of the scheduled cell. The processor2000may be an example of the processors102and202ofFIG.2.

FIG.7shows an example of a processor3000.

Referring toFIG.7, the processor3000may include a control information/data generation module3010and a transmission module3020. The processor3000may execute the methods described from the perspective of the transmitter inFIGS.26to30. For example, The processor3000may access a specific UE through a random access procedure. After that, The processor3000may transmit a higher layer signal for setting K0min or K2 min values to the UE. And the processor3000transmits, to the UE, downlink control information (DCI) including information for a change to a value of K0min or K2 min in a slot n of a scheduling cell, each of the K0min and K2 min being an applied minimum scheduling offset restriction. The processor3000may assume that the changed K0min or the changed K2 min value is applied in the slot n+X of the scheduling cell. The X value is a largest value among i) a first value obtained by multiplying currently applied K0 min (Y) in a scheduled cell scheduled by the DCI by 2μscheduling/2μscheduledand then performing ceiling and ii) a second value (Z) that are predetermined depending on a subcarrier spacing (SCS) of the scheduling cell. The μscheduling is a subcarrier spacing configuration of the scheduling cell and the μscheduled is a subcarrier spacing configuration of the scheduled cell. The processor3000may be an example of the processors102and202ofFIG.2.

FIG.8shows another example of a wireless device.

According toFIG.8, a wireless device may include at least one processor102,202, at least one memory104,204, at least one transceiver106,206, and one or more antennas108,208.

The example of the wireless device described inFIG.8is different from the example of the wireless described inFIG.2in that the processors102and202and the memories104and204are separated inFIG.2whereas the memories104and204are included in the processors102and202in the example ofFIG.8. That is, the processor and the memory may constitute one chipset.

FIG.9shows another example of a wireless device applied to the present specification. The wireless device may be implemented in various forms according to a use-case/service.

Referring toFIG.9, wireless devices100and200may correspond to the wireless devices ofFIG.2and may be configured by various elements, components, units/portions, and/or modules. For example, each of the wireless devices100and200may include a communication unit110, a control unit120, a memory unit130, and additional components140. The communication unit may include a communication circuit112and transceiver(s)114. For example, the communication circuit112may include the one or more processors102and202and/or the one or more memories104and204. For example, the transceiver(s)114may include the one or more transceivers106and206and/or the one or more antennas108and208ofFIG.2. The control unit120is electrically connected to the communication unit110, the memory130, and the additional components140and controls overall operation of the wireless devices. For example, the control unit120may control an electric/mechanical operation of the wireless device based on programs/code/commands/information stored in the memory unit130. In addition, the control unit120may transmit the information stored in the memory unit130to the exterior (e.g., other communication devices) via the communication unit110through a wireless/wired interface or store, in the memory unit130, information received through the wireless/wired interface from the exterior (e.g., other communication devices) via the communication unit110.

The additional components140may be variously configured according to types of wireless devices. For example, the additional components140may include at least one of a power unit/battery, input/output (I/O) unit, a driving unit, and a computing unit. The wireless device may be implemented in the form of, without being limited to, the robot (100aofFIG.1), the vehicles (100b-1and100b-2ofFIG.1), the XR device (100cofFIG.1), the hand-held device (100dofFIG.1), the home appliance (100eofFIG.1), the IoT device (100fofFIG.1), a digital broadcast UE, a hologram device, a public safety device, an MTC device, a medicine device, a fintech device (or a finance device), a security device, a climate/environment device, the AI server/device (400ofFIG.1), the BSs (200ofFIG.1), a network node, etc. The wireless device may be used in a mobile or fixed place according to a use—example/service.

InFIG.9, the entirety of the various elements, components, units/portions, and/or modules in the wireless devices100and200may be connected to each other through a wired interface or at least a part thereof may be wirelessly connected through the communication unit110. For example, in each of the wireless devices100and200, the control unit120and the communication unit110may be connected by wire and the control unit120and first units (e.g.,130and140) may be wirelessly connected through the communication unit110. In addition, each element, component, unit/portion, and/or module within the wireless devices100and200may further include one or more elements. For example, the control unit120may be configured by a set of one or more processors. For example, the control unit120may be configured by a set of a communication control processor, an application processor, an Electronic Control Unit (ECU), a graphical processing unit, and a memory control processor. For another example, the memory130may be configured by a Random Access Memory (RAM), a Dynamic RAM (DRAM), a Read Only Memory (ROM)), a flash memory, a volatile memory, a non-volatile memory, and/or a combination thereof.

FIG.10illustrates a hand-held device applied to the present specification. The hand-held device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or a smartglasses), or a portable computer (e.g., a notebook). The hand-held device may be referred to as a mobile station (MS), a user terminal (UT), a Mobile Subscriber Station (MSS), a Subscriber Station (SS), an Advanced Mobile Station (AMS), or a Wireless Terminal (WT).

Referring toFIG.10, a hand-held device100may include an antenna unit108, a communication unit110, a control unit120, a memory unit130, a power supply unit140a, an interface unit140b, and an I/O unit140c. The antenna unit108may be configured as a part of the communication unit110. Blocks110to130/140ato140crespective correspond to the blocks110to130/140ofFIG.9.

The communication unit110may transmit and receive signals (e.g., data and control signals) to and from other wireless devices or BSs. The control unit120may perform various operations by controlling constituent elements of the hand-held device100. The control unit120may include an Application Processor (AP). The memory unit130may store data/parameters/programs/code/commands needed to drive the hand-held device100. In addition, the memory unit130may store input/output data/information. The power supply unit140amay supply power to the hand-held device100and include a wired/wireless charging circuit, a battery, etc. The interface unit140bmay support connection of the hand-held device100to other external devices. The interface unit140bmay include various ports (e.g., an audio I/O port and a video I/O port) for connection with external devices. The I/O unit140cmay input or output video information/signals, audio information/signals, data, and/or information input by a user. The I/O unit140cmay include a camera, a microphone, a user input unit, a display unit140d, a speaker, and/or a haptic module.

For example, in the case of data communication, the I/O unit140cmay acquire information/signals (e.g., touch, text, voice, images, or video) input by a user and the acquired information/signals may be stored in the memory unit130. The communication unit110may convert the information/signals stored in the memory into radio signals and transmit the converted radio signals to other wireless devices directly or to a BS. In addition, the communication unit110may receive radio signals from other wireless devices or the BS and then restore the received radio signals into original information/signals. The restored information/signals may be stored in the memory unit130and may be output as various types (e.g., text, voice, images, video, or haptic) through the I/O unit140c.

FIG.11shows a wireless communication system to which the present disclosure may be applied. The wireless communication system may be referred to as an Evolved-UMTS Terrestrial Radio Access Network (E-UTRAN) or a Long Term Evolution (LTE)/LTE-A system.

The E-UTRAN includes at least one base station (BS)20which provides a control plane and a user plane to a user equipment (UE)10. The UE10may be fixed or mobile, and may be referred to as another terminology, such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a mobile terminal (MT), a wireless device, terminal, etc. The BS20is generally a fixed station that communicates with the UE10and may be referred to as another terminology, such as an evolved node-B (eNB), a base transceiver system (BTS), an access point, gNB, etc.

The BSs20are interconnected by means of an X2 interface. The BSs20are also connected by means of an S1 interface to an evolved packet core (EPC)30, more specifically, to a mobility management entity (MME) through S1-MME and to a serving gateway (S-GW) through S1-U.

The EPC30includes an MME, an S-GW, and a packet data network-gateway (P-GW). The MME has access information of the UE or capability information of the UE, and such information is generally used for mobility management of the UE. The S-GW is a gateway having an E-UTRAN as an end point. The P-GW is a gateway having a PDN as an end point.

Layers of a radio interface protocol between the UE and the network can be classified into a first layer (L1), a second layer (L2), and a third layer (L3) based on the lower three layers of the open system interconnection (OSI) model that is well-known in the communication system. Among them, a physical (PHY) layer belonging to the first layer provides an information transfer service by using a physical channel, and a radio resource control (RRC) layer belonging to the third layer serves to control a radio resource between the UE and the network. For this, the RRC layer exchanges an RRC message between the UE and the BS.

FIG.12is a diagram showing a wireless protocol architecture for a user plane.FIG.13is a diagram showing a wireless protocol architecture for a control plane. The user plane is a protocol stack for user data transmission. The control plane is a protocol stack for control signal transmission.

Referring toFIGS.12and13, a PHY layer provides an upper layer with an information transfer service through a physical channel. The PHY layer is connected to a medium access control (MAC) layer which is an upper layer of the PHY layer through a transport channel. Data is transferred between the MAC layer and the PHY layer through the transport channel. The transport channel is classified according to how and with what characteristics data is transferred through a radio interface.

Data is moved between different PHY layers, that is, the PHY layers of a transmitter and a receiver, through a physical channel. The physical channel may be modulated according to an Orthogonal Frequency Division Multiplexing (OFDM) scheme, and use the time and frequency as radio resources.

The functions of the MAC layer include mapping between a logical channel and a transport channel and multiplexing and demultiplexing to a transport block that is provided through a physical channel on the transport channel of a MAC Service Data Unit (SDU) that belongs to a logical channel. The MAC layer provides service to a Radio Link Control (RLC) layer through the logical channel.

The functions of the RLC layer include the concatenation, segmentation, and reassembly of an RLC SDU. In order to guarantee various types of Quality of Service (QoS) required by a Radio Bearer (RB), the RLC layer provides three types of operation mode: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). AM RLC provides error correction through an Automatic Repeat Request (ARQ).

The RRC layer is defined only on the control plane. The RRC layer is related to the configuration, reconfiguration, and release of radio bearers, and is responsible for control of logical channels, transport channels, and PHY channels. An RB means a logical route that is provided by the first layer (PHY layer) and the second layers (MAC layer, the RLC layer, and the PDCP layer) in order to transfer data between UE and a network.

The function of a Packet Data Convergence Protocol (PDCP) layer on the user plane includes the transfer of user data and header compression and ciphering. The function of the PDCP layer on the user plane further includes the transfer and encryption/integrity protection of control plane data.

What an RB is configured means a process of defining the characteristics of a wireless protocol layer and channels in order to provide specific service and configuring each detailed parameter and operating method. An RB can be divided into two types of a Signaling RB (SRB) and a Data RB (DRB). The SRB is used as a passage through which an RRC message is transmitted on the control plane, and the DRB is used as a passage through which user data is transmitted on the user plane.

If RRC connection is established between the RRC layer of UE and the RRC layer of an E-UTRAN, the UE is in the RRC connected state. If not, the UE is in the RRC idle state.

A downlink transport channel through which data is transmitted from a network to UE includes a broadcast channel (BCH) through which system information is transmitted and a downlink shared channel (SCH) through which user traffic or control messages are transmitted. Traffic or a control message for downlink multicast or broadcast service may be transmitted through the downlink SCH, or may be transmitted through an additional downlink multicast channel (MCH). Meanwhile, an uplink transport channel through which data is transmitted from UE to a network includes a random access channel (RACH) through which an initial control message is transmitted and an uplink shared channel (SCH) through which user traffic or control messages are transmitted.

Logical channels that are placed over the transport channel and that are mapped to the transport channel include a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and a multicast traffic channel (MTCH).

The physical channel includes several OFDM symbols in the time domain and several subcarriers in the frequency domain. One subframe includes a plurality of OFDM symbols in the time domain. An RB is a resources allocation unit, and includes a plurality of OFDM symbols and a plurality of subcarriers. Furthermore, each subframe may use specific subcarriers of specific OFDM symbols (e.g., the first OFDM symbol) of the corresponding subframe for a physical downlink control channel (PDCCH), that is, an L1/L2 control channel. A Transmission Time Interval (TTI) is a unit time for transmission.

Hereinafter, anew radio access technology (new RAT, NR) will be described.

As more and more communication devices require more communication capacity, there is a need for improved mobile broadband communication over existing radio access technology. Also, massive machine type communications (MTC), which provides various services by connecting many devices and objects, is one of the major issues to be considered in the next generation communication. In addition, communication system design considering reliability/latency sensitive service/UE is being discussed. The introduction of next generation radio access technology considering enhanced mobile broadband communication (eMBB), massive MTC (mMTC), ultrareliable and low latency communication (URLLC) is discussed. This new technology may be called new radio access technology (new RAT or NR) in the present disclosure for convenience.

FIG.14illustrates a system structure of a next generation radio access network (NG-RAN) to which NR is applied.

Referring toFIG.14, the NG-RAN may include a gNB and/or an eNB that provides user plane and control plane protocol termination to a UE.FIG.14illustrates the case of including only gNBs. The gNB and the eNB are connected by an Xn interface. The gNB and the eNB are connected to a 5G core network (5GC) via an NG interface. More specifically, the gNB and the eNB are connected to an access and mobility management function (AMF) via an NG-C interface and connected to a user plane function (UPF) via an NG-U interface.

FIG.15illustrates a functional division between an NG-RAN and a 5GC.

Referring toFIG.15, The gNB may provide functions such as an inter-cell radio resource management (Inter Cell RRM), radio bearer management (RB control), connection mobility control, radio admission control, measurement configuration & provision, dynamic resource allocation, and the like. The AMF may provide functions such as NAS security, idle state mobility handling, and so on. The UPF may provide functions such as mobility anchoring, PDU processing, and the like. The SMF may provide functions such as UE IP address assignment, PDU session control, and so on.

FIG.16illustrates an example of a frame structure that may be applied in NR.

Referring toFIG.16, a radio frame (which may be called as a frame hereinafter) may be used for uplink and downlink transmission in NR. A frame has a length of 10 ms and may be defined as two 5 ms half-frames (Half-Frame, HF). A half-frame may be defined as five 1 ms subframes (Subframe, SF). A subframe may be divided into one or more slots, and the number of slots in a subframe depends on subcarrier spacing (SCS). Each slot includes 12 or 14 OFDM(A) symbols according to a cyclic prefix (CP). When a normal CP is used, each slot includes 14 symbols. When an extended CP is used, each slot includes 12 symbols. Here, the symbol may include an OFDM symbol (or a CP-OFDM symbol) and an SC-FDMA symbol (or a DFT-s-OFDM symbol).

The following table 1 illustrates a subcarrier spacing configuration p.

TABLE 1μΔf = 2μ· 15[kHz]Cyclic prefix015Normal130Normal260NormalExtended3120Normal4240Normal

The following table 2 illustrates the number of slots in a frame (Nframe,μslot), the number of slots in a subframe (Nsubframe,μslot), the number of symbols in a slot (Nslotsymb), and the like, according to subcarrier spacing configurations p.

TABLE 2μNsymbslotNslotframe, μNslotsubframe, μ01410111420221440431480841416016

InFIG.16, μ=0, 1, 2, and 3 are exemplified.

Table 2-1 below exemplifies that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to SCS (μ=2, 60 kHz) when the extended CP is used.

TABLE 2-1μNsymbslotNslotframe, uNslotsubframe, u212404

In an NR system, OFDM(A) numerologies (e.g., SCS, CP length, and so on) may be differently configured between a plurality of cells integrated to one UE. Accordingly, an (absolute time) duration of a time resource (e.g., SF, slot or TTI) (for convenience, collectively referred to as a time unit (TU)) configured of the same number of symbols may be differently configured between the integrated cells.

FIG.17illustrates a slot structure of a NR frame.

A slot may comprise a plurality of symbols in a time domain. For example, in case of a normal CP, one slot may include 7 symbols. However, in case of an extended CP, one slot may include 6 symbols. The carrier may include a plurality of subcarriers in a frequency domain. A resource block (RB) may be defined as a plurality of consecutive subcarriers (e.g.,12) in the frequency domain. A bandwidth part (BWP) may be defined as a plurality of consecutive (P)RBs in the frequency domain, and may correspond to one numerology (e.g., SCS, CP length, etc.). A carrier may include a maximum of N (e.g., 5) BWPs. Data communication is performed through the activated BWP, and only one BWP can be activated for one UE. Each element in the resource grid is referred to as a resource element (RE), and one complex symbol may be mapped thereto.

A physical downlink control channel (PDCCH) may include one or more control channel elements (CCEs) as illustrated in the following table 3.

TABLE 3Aggregation levelNumber of CCEs112244881616

That is, the PDCCH may be transmitted through a resource including 1, 2, 4, 8, or 16 CCEs. Here, the CCE includes six resource element groups (REGs), and one REG includes one resource block in a frequency domain and one orthogonal frequency division multiplexing (OFDM) symbol in a time domain.

Monitoring means decoding each PDCCH candidate according to a downlink control information (DCI) format. The UE monitors a set of PDCCH candidates in one or more CORESETs (described below) on the activated DL BWP of each activated serving cell for which PDCCH monitoring is configured according to a corresponding search space set.

A new unit called a control resource set (CORESET) may be introduced in the NR. The UE may receive a PDCCH in the CORESET.

FIG.18illustrates a CORESET.

Referring toFIG.18, the CORESET includes NCORESETRBresource blocks in the frequency domain, and NCORESETsymb∈{1, 2, 3} number of symbols in the time domain. NCORESETRBand NCORESETsymbmay be provided by a base station via higher layer signaling. As illustrated inFIG.18, a plurality of CCEs (or REGs) may be included in the CORESET. One CCE may be composed of a plurality of resource element groups (REGs), and one REG may include one OFDM symbol in the time domain and 12 resource elements in the frequency domain.

The UE may attempt to detect a PDCCH in units of 1, 2, 4, 8, or 16 CCEs in the CORESET. One or a plurality of CCEs in which PDCCH detection may be attempted may be referred to as PDCCH candidates.

A plurality of CORESETs may be configured for the UE.

FIG.19is a diagram illustrating a difference between a conventional control region and the CORESET in NR.

Referring toFIG.19, a control region800in the conventional wireless communication system (e.g., LTE/LTE-A) is configured over the entire system band used by a base station (BS). All the UEs, excluding some (e.g., eMTC/NB-IoT UE) supporting only a narrow band, must be able to receive wireless signals of the entire system band of the BS in order to properly receive/decode control information transmitted by the BS.

On the other hand, in NR, CORESET described above was introduced. CORESETs801,802, and803are radio resources for control information to be received by the UE and may use only a portion, rather than the entirety of the system bandwidth in the frequency domain. In addition, in the time domain, only some of the symbols in the slot may be used. The BS may allocate the CORESET to each UE and may transmit control information through the allocated CORESET. For example, inFIG.19, a first CORESET801may be allocated to UE1, a second CORESET802may be allocated to UE2, and a third CORESET803may be allocated to UE3. In the NR, the UE may receive control information from the BS, without necessarily receiving the entire system band.

The CORESET may include a UE-specific CORESET for transmitting UE-specific control information and a common CORESET for transmitting control information common to all UEs.

Meanwhile, NR may require high reliability according to applications. In such a situation, a target block error rate (BLER) for downlink control information (DCI) transmitted through a downlink control channel (e.g., physical downlink control channel (PDCCH)) may remarkably decrease compared to those of conventional technologies. As an example of a method for satisfying requirement that requires high reliability, content included in DCI can be reduced and/or the amount of resources used for DCI transmission can be increased. Here, resources can include at least one of resources in the time domain, resources in the frequency domain, resources in the code domain and resources in the spatial domain.

In NR, the following technologies/features can be applied.

<Self-Contained Subframe Structure>

FIG.20illustrates an example of a frame structure for new radio access technology.

In NR, a structure in which a control channel and a data channel are time-division-multiplexed (TDMed) within one TTI, as shown inFIG.20, can be considered as a frame structure in order to minimize latency.

InFIG.20, a shaded region represents a downlink control region and a black region represents an uplink control region. The remaining region may be used for downlink (DL) data transmission or uplink (UL) data transmission. This structure is characterized in that DL transmission and UL transmission are sequentially performed within one subframe and thus DL data can be transmitted and UL ACK/NACK can be received within the subframe. Consequently, a time required from occurrence of a data transmission error to data retransmission is reduced, thereby minimizing latency in final data transmission.

In this data and control TDMed subframe structure, a time gap for a base station and a UE to switch from a transmission mode to a reception mode or from the reception mode to the transmission mode may be required. To this end, some OFDM symbols at a time when DL switches to UL may be set to a guard period (GP) in the self-contained subframe structure.

FIG.21illustrates a structure of self-contained slot.

In NR system, one slot includes all of a DL control channel, DL or UL data channel, UL control channel, and so on. For example, the first N symbols in a slot may be used for transmitting a DL control channel (in what follows, DL control region), and the last M symbols in the slot may be used for transmitting an UL control channel (in what follows, UL control region). N and M are each an integer of 0 or larger. A resource region located between the DL and UL control regions (in what follows, a data region) may be used for transmission of DL data or UL data. As one example, one slot may correspond to one of the following configurations. Each period is listed in the time order.1. DL only configuration2. UL only configuration3. Mixed UL-DL configurationDL region+GP (Guard Period)+UL control regionDL control region+GP+UL region

a DL region: (i) a DL data region, (ii) DL control region plus DL data region

a UL region: (i) an UL data region, (ii) UL data region plus UL control region.

In the DL control region, a PDCCH may be transmitted, and in the DL data region, a PDSCH may be transmitted. In the UL control region, a PUCCH may be transmitted, and in the UL data region, a PUSCH may be transmitted. In the PDCCH, Downlink Control Information (DCI), for example, DL data scheduling information or UL data scheduling information may be transmitted. In the PUCCH, Uplink Control Information (UCI), for example, ACK/NACK (Positive Acknowledgement/Negative Acknowledgement) information with respect to DL data, Channel State Information (CSI) information, or Scheduling Request (SR) may be transmitted. A GP provides a time gap during a process where a gNB and a UE transition from the transmission mode to the reception mode or a process where the gNB and UE transition from the reception mode to the transmission mode. Part of symbols belonging to the occasion in which the mode is changed from DL to UL within a subframe may be configured as the GP.

<Analog Beamforming #1>

Wavelengths are shortened in millimeter wave (mmW) and thus a large number of antenna elements can be installed in the same area. That is, the wavelength is 1 cm at 30 GHz and thus a total of 100 antenna elements can be installed in the form of a 2-dimensional array at an interval of 0.5 lambda (wavelength) in a panel of 5×5 cm. Accordingly, it is possible to increase a beamforming (BF) gain using a large number of antenna elements to increase coverage or improve throughput in mmW.

In this case, if a transceiver unit (TXRU) is provided to adjust transmission power and phase per antenna element, independent beamforming per frequency resource can be performed. However, installation of TXRUs for all of about 100 antenna elements decreases effectiveness in terms of cost. Accordingly, a method of mapping a large number of antenna elements to one TXRU and controlling a beam direction using an analog phase shifter is considered. Such analog beamforming can form only one beam direction in all bands and thus cannot provide frequency selective beamforming.

Hybrid beamforming (BF) having a number B of TXRUs which is smaller than Q antenna elements can be considered as an intermediate form of digital BF and analog BF. In this case, the number of directions of beams which can be simultaneously transmitted are limited to B although it depends on a method of connecting the B TXRUs and the Q antenna elements.

<Analog Beamforming #2>

When a plurality of antennas is used in NR, hybrid beamforming which is a combination of digital beamforming and analog beamforming is emerging. Here, in analog beamforming (or RF beamforming) an RF end performs precoding (or combining) and thus it is possible to achieve the performance similar to digital beamforming while reducing the number of RF chains and the number of D/A (or A/D) converters. For convenience, the hybrid beamforming structure may be represented by N TXRUs and M physical antennas. Then, the digital beamforming for the L data layers to be transmitted at the transmitting end may be represented by an N by L matrix, and the converted N digital signals are converted into analog signals via TXRUs, and analog beamforming represented by an M by N matrix is applied.

System information of the NR system may be transmitted in a broadcasting manner. In this case, in one symbol, analog beams belonging to different antenna panels may be simultaneously transmitted. A scheme of introducing a beam RS (BRS) which is a reference signal (RS) transmitted by applying a single analog beam (corresponding to a specific antenna panel) is under discussion to measure a channel per analog beam. The BRS may be defined for a plurality of antenna ports, and each antenna port of the BRS may correspond to a single analog beam. In this case, unlike the BRS, a synchronization signal or an xPBCH may be transmitted by applying all analog beams within an analog beam group so as to be correctly received by any UE.

In the NR, in a time domain, a synchronization signal block (SSB, or also referred to as a synchronization signal and physical broadcast channel (SS/PBCH)) may consist of 4 OFDM symbols indexed from 0 to 3 in an ascending order within a synchronization signal block, and a primary synchronization signal (PSS), secondary synchronization signal (SSS), and a PBCH associated with demodulation reference signal (DMRS) may be mapped to the symbols. As described above, the synchronization signal block may also be represented by an SS/PBCH block.

In NR, since a plurality of synchronization signal blocks(SSBs) may be transmitted at different times, respectively, and the SSB may be used for performing initial access (IA), serving cell measurement, and the like, it is preferable to transmit the SSB first when transmission time and resources of the SSB overlap with those of other signals. To this purpose, the network may broadcast the transmission time and resource information of the SSB or indicate them through UE-specific RRC signaling.

In NR, transmission and reception may be performed based on beams. If reception performance of a current serving beam is degraded, a process of searching for a new beam through the so-called Beam Failure Recovery (BFR) may be performed.

Since the BFR process is not intended for declaring an error or failure of a link between the network and a UE, it may be assumed that a connection to the current serving cell is retained even if the BFR process is performed. During the BFR process, measurement of different beams (which may be expressed in terms of CSI-RS port or Synchronization Signal Block (SSB) index) configured by the network may be performed, and the best beam for the corresponding UE may be selected. The UE may perform the BFR process in a way that it performs an RACH process associated with a beam yielding a good measurement result.

Now, a transmission configuration indicator (hereinafter, TCI) state will be described. The TCI state may be configured for each CORESET of a control channel, and may determine a parameter for determining an RX beam of the UE, based on the TCI state.

For each DL BWP of a serving cell, a UE may be configured for three or fewer CORESETs. Also, a UE may receive the following information for each CORESET.1) CORESET index p (e.g., one of 0 to 11, where index of each CORESET may be determined uniquely among BWPs of one serving cell),2) PDCCH DM-RS scrambling sequence initialization value,3) Duration of a CORESET in the time domain (which may be given in symbol units),4) Resource block set,5) CCE-to-REG mapping parameter,6) Antenna port quasi co-location indicating quasi co-location (QCL) information of a DM-RS antenna port for receiving a PDCCH in each CORESET (from a set of antenna port quasi co-locations provided by a higher layer parameter called ‘TCI-State’),

7) Indication of presence of Transmission Configuration Indication (TCI) field for a specific DCI format transmitted by the PDCCH in the CORESET, and so on.

QCL will be described. If a characteristic of a channel through which a symbol on one antenna port is conveyed can be inferred from a characteristic of a channel through which a symbol on the other antenna port is conveyed, the two antenna ports are said to be quasi co-located (QCLed). For example, when two signals A and B are transmitted from the same transmission antenna array to which the same/similar spatial filter is applied, the two signals may go through the same/similar channel state. From a perspective of a receiver, upon receiving one of the two signals, another signal may be detected by using a channel characteristic of the received signal.

In this sense, when it is said that the signals A and B are quasi co-located (QCLed), it may mean that the signals A and B have went through a similar channel condition, and thus channel information estimated to detect the signal A is also useful to detect the signal B. Herein, the channel condition may be defined according to, for example, a Doppler shift, a Doppler spread, an average delay, a delay spread, a spatial reception parameter, or the like.

A ‘TCI-State’ parameter associates one or two downlink reference signals to corresponding QCL types (QCL types A, B, C, and D, see Table 4).

TABLE 4QCL TypeDescriptionQCL-TypeADoppler shift, Doppler spread, Average delay, DelayspreadQCL-TypeBDoppler shift, Doppler spreadQCL-TypeCDoppler shift, Average delayQCL-TypeDSpatial Rx parameter

Each ‘TCI-State’ may include a parameter for configuring a QCL relation between one or two downlink reference signals and a DM-RS port of a PDSCH (or PDDCH) or a CSI-RS port of a CSI-RS resource.

Meanwhile, for each DL BWP configured to a UE in one serving cell, the UE may be provided with 10 (or less) search space sets. For each search space set, the UE may be provided with at least one of the following information.

1) search space set index s (0≤s<40), 2) an association between a CORESET p and the search space set s, 3) a PDCCH monitoring periodicity and a PDCCH monitoring offset (slot unit), 4) a PDCCH monitoring pattern within a slot (e.g., indicating a first symbol of a CORSET in a slot for PDCCH monitoring), 5) the number of slots in which the search space set s exists, 6) the number of PDCCH candidates per CCE aggregation level, 7) information indicating whether the search space set s is CSS or USS.

In the NR, a CORESET#0 may be configured by a PBCH (or a UE-dedicated signaling for handover or a PSCell configuration or a BWP configuration). A search space (SS) set#0 configured by the PBCH may have monitoring offsets (e.g., a slot offset, a symbol offset) different for each associated SSB. This may be required to minimize a search space occasion to be monitored by the UE. Alternatively, this may be required to provide a beam sweeping control/data region capable of performing control/data transmission based on each beam so that communication with the UE is persistently performed in a situation where a best beam of the UE changes dynamically.

FIG.22illustrates physical channels and typical signal transmission.

Referring toFIG.22, in a wireless communication system, a UE receives information from a BS through a downlink (DL), and the UE transmits information to the BS through an uplink (UL). The information transmitted/received by the BS and the UE includes data and a variety of control information, and there are various physical channels according to a type/purpose of the information transmitted/received by the BS and the UE.

The UE which is powered on again in a power-off state or which newly enters a cell performs an initial cell search operation such as adjusting synchronization with the BS or the like (S11). To this end, the UE receives a primary synchronization channel (PSCH) and a secondary synchronization channel (SSCH) from the BS to adjust synchronization with the BS, and acquire information such as a cell identity (ID) or the like. In addition, the UE may receive a physical broadcast channel (PBCH) from the BS to acquire broadcasting information in the cell. In addition, the UE may receive a downlink reference signal (DL RS) in an initial cell search step to identify a downlink channel state.

Upon completing the initial cell search, the UE may receive a physical downlink control channel (PDCCH) and a physical downlink control channel (PDSCH) corresponding thereto to acquire more specific system information (S12).

Thereafter, the UE may perform a random access procedure to complete an access to the BS (S13-S16). Specifically, the UE may transmit a preamble through a physical random access channel (PRACH) (S13), and may receive a random access response (RAR) for the preamble through a PDCCH and a PDSCH corresponding thereto (S14). Thereafter, the UE may transmit a physical uplink shared channel (PUSCH) by using scheduling information in the RAR (S15), and may perform a contention resolution procedure similarly to the PDCCH and the PDSCH corresponding thereto (S16).

After performing the aforementioned procedure, the UE may perform PDCCH/PDSCH reception (S17) and PUSCH/physical uplink control channel (PUCCH) transmission (S18) as atypical uplink/downlink signal transmission procedure. Control information transmitted by the UE to the BS is referred to as uplink control information (UCI). The UCI includes hybrid automatic repeat and request (HARQ) acknowledgement (ACK)/negative-ACK (NACK), scheduling request (SR), channel state information (CSI), or the like. The CSI includes a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indication (RI), or the like. In general, the UCI is transmitted through the PUCCH. However, when control information and data are to be transmitted simultaneously, the UCI may be transmitted through the PUSCH. In addition, the UE may aperiodically transmit the UCI through the PUSCH according to a request/instruction of a network.

In order to enable reasonable battery consumption when bandwidth adaptation (BA) is configured, only one uplink BWP and one downlink BWP or only one downlink/uplink BWP pair for each uplink carrier may be activated at once in an active serving cell, and all other BWPs configured in the UE are deactivated. In the deactivated BWPs, the UE does not monitor the PDCCH, and does not perform transmission on the PUCCH, PRACH, and UL-SCH.

For the BA, RX and TX bandwidths of the UE are not necessarily as wide as a bandwidth of a cell, and may be adjusted. That is, it may be commanded such that a width is changed (e.g., reduced for a period of low activity for power saving), a position in a frequency domain is moved (e.g., to increase scheduling flexibility), and a subcarrier spacing is changed (e.g., to allow different services). A subset of the entire cell bandwidth of a cell is referred to as a bandwidth part (BWP), and the BA is acquired by configuring BWP(s) to the UE and by notifying the UE about a currently active BWP among configured BWPs. When the BA is configured, the UE only needs to monitor the PDCCH on one active BWP. That is, there is no need to monitor the PDCCH on the entire downlink frequency of the cell. A BWP inactive timer (independent of the aforementioned DRX inactive timer) is used to switch an active BWP to a default BWP. That is, the timer restarts when PDCCH decoding is successful, and switching to the default BWP occurs when the timer expires.

FIG.23illustrates a scenario in which three different bandwidth parts are configured.

FIG.23shows an example in which BWP1, BWP2, and BWP3are configured on a time-frequency resource. The BWP1may have a width of 40 MHz and a subcarrier spacing of 15 kHz. The BWP2may have a width of 10 MHz and a subcarrier spacing of 15 kHz. The BWP3may have a width of 20 MHz and a subcarrier spacing of 60 kHz. In other words, each BWP may have a different width and/or a different subcarrier spacing.

Hereinafter, the present disclosure proposes a cross-slot scheduling method and an apparatus using the method in a wireless communication system.

In NR, a power saving technique is being discussed to reduce the power consumption of the UE, and among the techniques, there is a power saving technique using cross-slot scheduling.

A power saving technique using cross-slot scheduling indicates a minimum slot offset between the DCI and the PDSCH scheduled in the DCI. Power consumption can be reduced by a method in which the UE (micro-) sleeps or applies PDCCH decoding relaxation (e.g., using a low voltage/low clock speed) in a duration guaranteed by the minimum slot offset. For example, assume that the minimum slot offset is 2. In this case, if the UE receives DCI in slot #N, the UE sleeps in slot #N+1 and wakes up in slot #N+2 to receive the PDSCH scheduled by the DCI. Since the minimum slot offset is 2, it is okay to sleep in slot #N+1. The minimum slot offset may be referred to as a minimum applicable slot offset or a minimum applicable offset, a minimum scheduling offset, or the like.

As a specific example, the network may set a minimum applicable K0/K2 value to indicate to the UE the minimum slot offset between the DCI and the corresponding scheduled PDSCH/PUSCH when scheduling a PDSCH or a PUSCH. Here, K0 may be an offset (slot offset) related to a time relationship between a slot in which DCI is received and a slot in which a PDSCH scheduled by the DCI is received. K0 may be based on the numerology of the PDSCH. K2 may be an offset (slot offset) related to a time relationship between a slot in which DCI is received and a slot in which a PUSCH scheduled by the DCI is transmitted. K2 may be based on the numerology of PUSCH. It can be seen that the minimum applicable K0 indicates the minimum applicable value (restriction) in setting the K0 value, and the minimum applicable K2 indicates the minimum applicable value (restriction) in the setting of the K2 value. Hereinafter, the minimum applicable K0 may be expressed as K0min, and the minimum applicable K2 may be expressed as K2 min.

For example, the base station may instruct K0 and K2 to the UE in the following manner.

When the UE is scheduled to receive the PDSCH by DCI, the time domain resource assignment field value m of DCI provides the row index m+1 in the resource allocation table. The indexed row directly defines the slot offset K0, the start and length indicator SLIV or the start symbol S and the allocation length L, and the PDSCH mapping type assumed in PDSCH reception.

The following table is an example of a resource allocation table.

TABLE 5dmrs-TypeA-PDSCHRow indexPositionmapping typeK0SL12Type A02123Type A031122Type A02103Type A03932Type A0293Type A03842Type A0273Type A03652Type A0253Type A03462Type B0943Type B010472Type B0443Type B06482, 3Type B05792, 3Type B052102, 3Type B092112, 3Type B0122122, 3Type A0113132, 3Type A016142, 3Type A024152, 3Type B047162, 3Type B084

Given the parameter value of the indexed row, the slot allocated to the PDSCH is floor(n·(2μPDSCH/2μPDCCH))+K0. Here, n is a slot with a scheduling DCI, and K0 is based on the numerology of the PDSCH. Each of μPDSCHand μPDCCHis a subcarrier spacing configuration for each of PDSCH and PDCCH.

The start symbol S for the start of the slot and L (the number of symbols allocated to the PDSCH), which is the number of consecutive symbols counted from the symbol S, are determined from the ‘start and length indicator’ SLIV.

J When the UE is scheduled to transmit a transport block but no CSI report, or when the UE is scheduled to transmit a transport block and CSI report(s) in PUSCH by DCI, the time domain resource assignment field value m of the DCI provides the row index m+1 in the allocated table. The indexed row directly defines a slot offset K2, a start and length indicator SLIV or a start symbol S and an allocation length L, and a PUSCH mapping type to be applied to PUSCH transmission.

The slot in which the UE should transmit the PUSCH may be determined, by K2, as floor(n·(2μPUSCH/2μPDCCH))+K2. Here, n is a slot with a scheduling DCI, and K2 is based on the numerology of PUSCH. μPUSCHand μPDCCHare subcarrier spacing configurations for PUSCH and PDCCH, respectively.

The start symbol S for the start of a slot (relative to the start of the slot) and L, the number of consecutive symbols allocated to the PUSCH counted from the symbol S, is determined from the start and length indicator SLIV of the indexed row.

On the other hand, in the case of instructing/changing the minimum applicable K0/K2 (K0min/K2 min), when the corresponding instruction/change is applied may be determined by “application delay”, and the application delay may be defined as follows. Hereinafter, for convenience, the application delay may be expressed as X or the application delay X.

For the application delay X to apply the minimum applicable K0/K2 value(s) indicated for the scheduled cell, triggered by a 1-bit indication of DCI format 1_1 or 0_1 in the scheduling cell,

the UE receives DCI indicating a change of the minimum applicable K0/K2 value in slot n of the scheduling cell,

The UE may assume that a new minimum applicable K0/K2 value is applied to the PDSCH/PUSCH of the scheduled cell from the slot (n+X) of the scheduling cell. That is, when DCI indicating a change of the minimum applicable K0/K2 value is received in slot n of the scheduling cell, the changed minimum applicable K0/K2 value is applied from slot n+X of the scheduling cell.

In case of self-carrier scheduling and at least PDCCH monitoring case 1-1 (to be described later), X=max(Y, Z). Here, Y is the active minimum applicable K0 value of the active DL BWP before the change indication, Z is (1, 1, 2, 2) for each downlink subcarrier spacing (DL SCS) (15, 30, 60, 120) kHz, respectively.

In the above definition, Z may be defined as “the minimum feasible non-zero application delay that may depend on DL SCS”, and it might be interpreted as the minimum time for PDCCH decoding.

The Z value is applied when Y is 0 or less than Z. In this case, the new minimum applicable value K0/K2 (K0min/K2 min) may mean that it is applied from the point in time when the UE recognizes the corresponding value (i.e., the time when PDCCH decoding ends).

FIG.24is an example of applying an application delay.

Referring toFIG.24(a), the UE receives DCI in slot m, and receives the PDSCH scheduled by the DCI in slot m+K0. In this case, for example, it is assumed that the K0min value that is the minimum applicable slot offset is 1 and the K0 value is 2. Then, the UE may receive DCI including information indicating a change of the minimum applicable slot offset in slot n. Through this, for example, suppose that the value of K0min is changed to 0. In this case, the change of the minimum applicable slot offset is applied from slot n+X, not from slot n. The value of X may be determined to be a largest value among Y and Z, such as max(Y, Z). Here, Y is the active minimum applicable K0 value of the active DL BWP before the change indication, Z may be (1, 1, 2, 2) in turn for the case where the DL SCS is (15, 30, 60, 120) kHz. In slot n+X, the UE may receive a DCI indicating 0 as a value of K0, and may also receive a PDSCH scheduled by the DCI.

Referring toFIG.24(b), the UE may receive DCI#1 including information indicating a change of the minimum applicable slot offset in slot n. In this case, the changed minimum applicable slot offset (let's call it K0minNew) is applied from slot n+X, not directly applied from slot n. That is, DCI#2 received in slot n+X indicates a K0 value greater than or equal to K0minNew. From the UE's point of view, from slot n+X, it is expected to receive a DCI indicating a K0 value greater than or equal to K0minNew. Until slot n+X, the existing minimum applicable slot offset (let's call this K0minOld) is applied.

PDCCH monitoring case 1-1, case 1-2, and case 2 may be defined as follows.

Case 1: a case that the PDCCH monitoring period is 14 or more symbols.

Case 1-1: a case that PDCCH monitoring is performed on up to 3 OFDM symbols from the beginning of a slot.

Case 1-2: a case that PDCCH monitoring is performed on any up to 3 consecutive OFDM symbols of a slot.

For a given UE, all search space configurations are within the same range of three consecutive OFDM symbols in a slot.

Case 2: a case that the PDCCH monitoring period is less than 14 symbols. This includes monitoring the PDCCH on up to 3 OFDM symbols from the beginning of the slot.

This disclosure proposes a method of defining ‘application delay’ in each case and cross-carrier scheduling.

<Application Delay>

FIG.25illustrates a location of a CORESET for PDCCH monitoring.

Referring toFIG.25, the first CORESET151for PDCCH monitoring is located within the first three symbols of the slot, and the second CORESET152for PDCCH monitoring is located outside the first three symbols of the slot, for example, may be located in the last three symbols of the slot. It can be seen that the first CORESET151corresponds to the aforementioned cases 1-1 and 1-2, and the second CORESET152corresponds to the aforementioned cases 1-2.

That is, in case 1-2, unlike case 1-1 (the CORESET for PDCCH monitoring is located within the first 3 symbols in the slot), there is no position restriction in the slot of the CORESET for monitoring the PDCCH. As shown inFIG.25, the network may instruct the UE to position the CORESET in the last 3 symbols in the slot and monitor the PDCCH. This means that the PDCCH decoding end time (i.e., DCI decoding end time) may be different depending on the location of the CORESET. In determining the application delay X value for indicating the change of the minimum applicable value K0/K2 (K0min/K2 min) through DCI and determining the application timing, this point should be considered.

For example, when Y=0, Z=1, X=max(Y,Z)=1 is given. This means that the changed minimum applicable value K0/K2 (K0min/K2 min) is applied to the slot immediately following the change indicated. However, there may be cases where this is not possible.

For example, PDCCH decoding may end in the next slot. For example, if the CORESET for PDCCH monitoring is located in the last 3 symbols of a slot, the UE will receive the PDCCH in the last 3 symbols and then decode the PDCCH in the next slot. Therefore, it may not be possible to apply the PDCCH decoding result from the beginning of the next slot.

In order to solve such a problem, the present disclosure proposes the following method. A solution method using the Z value is proposed below, but the same method may be applied to the X or Y value.

Option 1) It can be applied by adding a specific value (e.g., 1) to the predefined Z value.

Option 1 is the simplest solution, and in cases 1-2, the application delay can be derived by adding a specific value (e.g., 1) to the Z value. In this case, the specific value may be predefined or indicated through higher layer signaling (e.g., RRC, MAC CE, etc.) of the network.

Option 2) Determining the Z value based on the location of the CORESET (group).

The UE may determine whether to add a specific value (e.g., 1) to the Z value according to the location of the CORESET to be monitored in the corresponding slot. To this end, the location of the CORESET serving as a reference may be defined in advance or may be indicated by higher layer signaling of the network. Alternatively, the reference position of the CORESET may be determined according to the decoding capability of the UE. In this case, the UE may report the decoding capability (e.g., the position of the CORESET capable of terminating PDCCH decoding within the corresponding slot).

As the CORESET, all CORESETs monitored in the corresponding slot may be considered, or the CORESET, where non-fallback DCI to which the minimum applicable K0/K2 may be indicated is monitored, may be limitedly applied to.

For example, when all or part of the CORESET (in which PDCCH monitoring needs to be performed) exists after a specific symbol index (indicated in advance, or indicated by higher layer signaling of the network, or indicated by the capability reported by the UE), the UE may derive an application delay by adding a specific value (e.g., 1) to a predefined Z value.

Option 3) Z values specific to the case 1-2.

The network may separately indicate the Z value to be applied to Case 1-2. Alternatively, the Z value for Case 1-2 may be determined by a predefined definition. In addition, as in option 2, it may determine whether to apply the Z value for the case 1-2 depending on the location of the CORESET, in option 3.

Case 2.

Case 2 refers to a case in which a plurality of monitoring occasions of a specific search space set are set (or can be set) in one slot. In case 2, the following method can be considered.

Option 1) A method that does not apply the power saving technique using cross-slot scheduling to case 2.

As described above, the power saving technique using cross-slot scheduling is a scheme of performing a power saving operation during a slot offset between the PDCCH and the scheduled PDSCH. However, in case 2, since one search space set may have a plurality of monitoring occasions within one slot, it may be difficult to expect power savings due to sleep or the like. Therefore, in case 2, it can be assumed that the power saving operation by the minimum applicable K0 is not performed.

In addition, the PDCCH monitoring occasion is determined by the search space set setting. When a plurality of search space sets are configured, different cases may be applied to each slot. Therefore, when different cases are applied to each slot, option 1 may be interpreted as suggesting that it is assumed that cross-slot scheduling is not applied in the slot corresponding to case 2 or that the minimum applicable value K0/K2 is not changed in the slot corresponding to case 2.

As another method, when the minimum applicable value K0/K2 is newly indicated (i.e., changed) by DCI transmitted in the slot corresponding to case 2, the UE may ignore the indication. This method can be applied to case 1-2 as well as case 2.

Option 2) A method of applying an application delay for each monitoring occasion

Since the application delay means the time when the newly indicated minimum applicable values K0/K2 are applied, a method of defining the application delay for each monitoring occasion may also be considered. Therefore, in case 2, application delay can be applied for each monitoring occasion, this may mean that the application delay derivation method applied to Case 1-1 and Case 1-2 is applied according to the location of the monitoring occasion in the slot.

<Cross Carrier Scheduling>

Cross-carrier scheduling refers to a method of scheduling a PDSCH of a scheduled cell (a cell which is scheduled) in a PDCCH of a scheduling cell (a cell performing scheduling). That is, the PDCCH for PDSCH scheduling is decoded in the scheduling cell (more specifically, the active DL BWP of the scheduling cell), and scheduling of the PDSCH transmitted in the scheduled cell (more specifically, the active DL BWP of the scheduled cell) is performed through the corresponding DCI.

When applying a power saving technique using cross-slot scheduling in a scheduled cell (active BWP), the application delay for the minimum applicable value K0/K2 of the scheduled cell (active BWP) may be defined in the following method.

Option 1) Scheduling cell (active BWP) based application delay

The application delay can be interpreted as an offset from the slot in which the DCI indicating the new minimum applicable K0/K2 is transmitted to the slot to which the corresponding value is actually applied. This is closely related to PDCCH decoding. As described above, since the cross-carrier scheduling is a process of scheduling the PDSCH of a scheduled cell through the PDCCH in the scheduling cell, it may be desirable to replace the application delay of the minimum applicable value K0/K2 of the scheduled cell with the application delay of the scheduling cell (active BWP). Therefore, the present disclosure proposes to determine Y and/or Z, which are parameters for determining the application delay, based on the scheduling cell.

For example, in cross-carrier scheduling, the application delay of the scheduled cell may be determined as follows. (Alternatively, it may be defined to follow the application delay of the scheduling cell.)

For the application delay X to apply the minimum applicable K0/K2 value(s) indicated for the scheduled cell, triggered by a 1-bit indication of DCI format 1_1 or 0_1 in the scheduling cell,

the UE receives DCI indicating a change in slot n of the scheduling cell,

the UE may be scheduled with the minimum applicable K0/K2 value for the PDSCH/PUSCH of the scheduled cell in DCI in the slot (n+X) of the scheduling cell.

For cross-carrier scheduling, X=max(Y, Z). Here, Y is the active minimum applicable K0 value of the active DL BWP of the scheduling cell, and Z is (1, 1, 2, 2) for each downlink subcarrier spacing (DL SCS) (15, 30, 60, 120) kHz of the active BWP of the scheduling cell, respectively.

Option 2) Application delay based on scheduled cell (active BWP)

When the UE separately performs processing (e.g., PDCCH decoding) for the scheduling cell and the scheduled cell, the PDCCH scheduling the PDSCH of the scheduled cell is transmitted in the scheduling cell, but the application delay for the change of the minimum applicable value of the scheduled cell may be determined based on the scheduled cell. However, in this case, if the scheduling cell and the scheduled cell have different numerology, a process of scaling to fit the numerology of the scheduling cell may be required. For example, in cross-carrier scheduling, the application delay of the scheduled cell may be determined as follows.

In the application delay X for applying the minimum applicable K0/K2 value(s) indicated for the scheduled cell triggered by the 1-bit indication of DCI format 1_1 or 0_1 in the scheduling cell,

the UE receives DCI indicating a change in slot n of the scheduling cell,

the UE may be scheduled with the minimum applicable K0/K2 value for the PDSCH/PUSCH of the scheduled cell in DCI in the slot (n+X) of the scheduling cell.

For cross-carrier scheduling, X=max(Y, Z)·(2μscheduling/2μscheduled) or X=ceil(max(Y, Z)·(2μscheduling/2μscheduled)). Here, Y is the active minimum applicable K0 value of the active DL BWP of the scheduled cell before the change indication. For each downlink subcarrier spacing (DL SCS) (15, 30, 60, 120) kHz of the active BWP of the scheduled cell, z is (1, 1, 2, 2) respectively.

In the above formula, μschedulingdenotes the scheduling cell's numerology (subcarrier spacing configuration), and μscheduleddenotes the scheduled cell's numerology (subcarrier spacing configuration). For {15 kHz, 30 kHz, 60 kHz, 120 kHz}, it may have values of {0, 1, 2, 3} respectively.

Option 3) Combination of Option 1 and 2

Parameters Y and Z may be determined based on a scheduled cell and a scheduling cell, respectively. For example, since Y means the minimum applicable value K0/K2 before change, it is determined based on the scheduled cell to which the minimum applicable value is applied. And Z may be determined based on a scheduling cell in which actual PDCCH decoding is performed.

In cross-carrier scheduling, the application delay of the scheduled cell may be determined as follows.

In the application delay X for applying the minimum applicable K0/K2 value(s) (K0min/K2 min) indicated for the scheduled cell triggered by the 1-bit indication of DCI format 1_1 or 0_1 in the scheduling cell,

the UE receives DCI indicating a change in slot n of the scheduling cell,

the UE may be scheduled with the minimum applicable K0/K2 value for the PDSCH/PUSCH of the scheduled cell in DCI in the slot (n+X) of the scheduling cell.

For cross-carrier scheduling, X=max(Y·(2μscheduling/2μscheduled), Z) or X=max(ceil(Y·(2μscheduling/2μscheduled)), Z). Here, Y is the active minimum applicable K0 value of the active DL BWP of the scheduled cell before the change indication, Z is (1, 1, 2, 2) for each downlink subcarrier spacing (DL SCS) (15, 30, 60, 120) kHz of the active BWP of the scheduling cell, respectively.

FIG.26illustrates a method for determining an application delay value according to option 3.

Referring toFIG.26, the UE may access the base station through a random access procedure (S260). For example, the UE may transmit a random access preamble to the base station and receive a random access response (RAR) signal for the random access preamble from the base station. The UE may transmit a PUSCH by using the scheduling information in the RAR, and may perform a contention resolution procedure such as a PDCCH and a corresponding PDSCH.

After the UE accesses the base station, the UE receives downlink control information (DCI) including information indicating a change to the value of K0min or K2 min in slot n of a scheduling cell (S261). The DCI may be received in symbols before a specific symbol index of the slot n (e.g., the first 3 symbols of the slot n).

Each of the K0min and K2 min is an applied minimum scheduling offset restriction. Specifically, the K0min may be a minimum scheduling offset restriction related to a minimum value of an offset between a slot for receiving the first DCI and a slot for receiving a physical downlink shared channel (PDSCH) scheduled by the first DCI, the K2 min may be a minimum scheduling offset restriction related to a minimum value of an offset between a slot for receiving the second DCI and a slot for transmitting a physical uplink shared channel (PUSCH) scheduled by the second DCI.

The UE may determine the application delay X as a largest value among i) a first value obtained by multiplying currently applied K0min (let's call this Y) in a scheduled cell scheduled by the DCI by 2μscheduling/2μscheduledand then performing ceiling and ii) a second value (let's call this Z) that are predetermined depending on a subcarrier spacing (SCS) of the scheduling cell (S262).

That is, the application delay X can be determined by the following equation.

X=max⁢(⌈Y·2μs⁢cheduling2μscheduled⌉,Z)[Equation⁢1]

The μschedulingis a subcarrier spacing configuration of the scheduling cell (That is, subcarrier spacing configuration associated with PDCCH, therefore, μschedulingmay be expressed as μPDCCH) and the μscheduledis a subcarrier spacing configuration of the scheduled cell (That is, subcarrier spacing configuration associated with PDSCH, therefore, μscheduledmay be expressed as μPDSCH). The Y is the K0min value currently applied to the scheduled cell, and the Z is the second value.

Z may be predetermined as shown in the following table depending on the subcarrier spacing (SCS) (or subcarrier spacing configuration p) of the scheduling cell.

TABLE 6μZ01112232

That is, when the subcarrier spacing (SCS) of the scheduling cell is 15, 30, 60, and 120 kHz, the Z value may be predetermined as 1, 1, 2, 2, respectively.

The UE applies the changed K0min or the changed K2 min value from the slot n+X of the scheduling cell (S263).

On the other hand, as described above in ‘Option 2) Determining the Z value based on the location of the CORESET (group), if the DCI is received in symbols after the specific symbol index of slot n (e.g., symbols outside the first 3 symbols of slot n), after increasing the second value Z by 1, the value of X is determined. The reason for doing this is considering that the decoding (complete) timing of the DCI may be slot n+1 instead of slot n depending on the location of the CORESET.

For example, let assume that downlink control information (DCI) including information indicating a change in the value of K0min or K2 min is received in the last three symbols of slot n. In this case, Equation 1 is used in obtaining the application delay X, but the Z value from Table 6 is incremented by one (i.e., Z+1), instead of the Z value from Table 6, and then used for Z of Equation 1.

FIG.27is an example of applying the method ofFIG.26.

Referring toFIG.27, it is assumed that the subcarrier spacing (SCS) configuration of the scheduling cell is μ=0, and the SCS configuration μ=1 of the scheduled cell. It is assumed that K0 min (i.e., Y) currently applied to the scheduled cell is referred to as K0minOld for convenience, and its value is 1. Since the subcarrier spacing (SCS) configuration of the scheduling cell μ=0, Z=1.

DCI including information indicating a change to K0min may be received within the first three symbols of the slot n of the active DL BWP of the scheduling cell. Also, assume that the DCI is a DCI for cross-carrier scheduling.

The DCI may be, for example, DCI format 0_1 for scheduling one or more PUSCHs and DCI format 1_1 for scheduling PDSCH. Each of DCI format 0_1 and DCI format 1_1 may or may not include a 1-bit ‘Minimum applicable scheduling offset indicator’,FIG.27exemplifies an inclusion case. In case of DCI format 0_1, when the value of ‘Minimum applicable scheduling offset indicator’ is 0, it indicates the first value among the K2 min values set by the higher layer signal. When the value of ‘Minimum applicable scheduling offset indicator’ is 1, it indicates the second value (if any) or 0 (if there is no second value) among the K2 min values set by the higher layer signal. In case of DCI format 1_1, when the value of ‘Minimum applicable scheduling offset indicator’ is 0, it indicates the first value among the K0min values set by the higher layer signal. When the value of ‘Minimum applicable scheduling offset indicator’ is 1, it indicates the second value (if any) or 0 (if there is no second value) among the K0min values set by the higher layer signal.

It is possible to determine whether a change in the K0 min/K2 min value is indicated according to the value of K0 min/K2 min indicated by the value of ‘Minimum applicable scheduling offset indicator’.

When the DCI indicates a change in the value of K0min (/K2 min), the time point at which the changed K0 min(/K2 min) is applied is slot n+X, where X is X=max(ceil(1.20/21),1)=1 according to Equation 1 above. Accordingly, the time point at which the changed K0min/K2 min is applied becomes slot n+1.

FIG.28is another example of applying the method ofFIG.26.

Referring toFIG.28, it is assumed that the subcarrier spacing (SCS) configuration of the scheduling cell is μ=2, and the SCS configuration of the scheduled cell is μ=1. It is assumed that K0min (i.e., Y) currently applied to the scheduled cell is referred to as K0minOld for convenience, and its value is 1. Since the subcarrier spacing (SCS) configuration of the scheduling cell is μ=2, Z=2.

DCI including information indicating a change of K0min may be received within the first three symbols of the slot n of the active DL BWP of the scheduling cell. Also, assume that the DCI is a DCI for cross-carrier scheduling.

When the DCI indicates a change in the value of K0 min(/K2 min), the time point at which the changed K0 min(/K2 min) is applied is slot n+X, where X is, according to Equation 1, X=max(ceil(1,22/21),2)=2. Accordingly, the time point at which the changed K0 min/K2 min is applied becomes slot n+2.

FIG.29illustrates a signaling method between a network (base station) and a UE.

Referring toFIG.29, the UE accesses the base station through a random access procedure (S290). The random access procedure has already been described above. Thereafter, the base station provides a higher layer signal for setting K0min values to the UE (S291). the base station provides a higher layer signal for setting K0min values to the UE (S191). For example, ‘minimumSchedulingOffsetK0’ may be provided through ‘PDSCH-Config’ used to set UE-specific PDSCH parameters, and ‘minimumSchedulingOffsetK0’ may include a list of K0min values.

The base station transmits the first DCI including information indicating a change to K0min to the UE in slot n of the scheduling cell (S292). The first DCI may be DCI format 1_1. The first DCI may be transmitted within the first three symbols of slot n or outside the first three symbols, and the Z value used to determine the application delay X may vary depending on where the first DCI is transmitted. This has already been described above. The first DCI may inform the change of K0min through a 1-bit field. This has already been described above.

The UE determines an application delay value X related to the time of applying the changed K0min (S293). As described above, the X value may be determined based on the current K0min of the scheduled cell, the SCS configurations of the scheduling cell and the scheduled cell, and a predetermined value dependent on the SCS configuration of the scheduling cell. For example, Equation 1 can be used.

The base station transmits the second DCI to which the changed K0min is applied (a second DCI based on the changed K0min) in slot n+X of the scheduling cell (S294). Thereafter, the PDSCH scheduled by the second DCI is transmitted in the scheduled cell (S295). The time interval between the second DCI and the PDSCH must be equal to or greater than the changed K0min. In the time interval, the UE may perform a sleep operation or a PDCCH decoding relaxation operation to save power.

FIG.30illustrates a signaling method between a network (base station) and a UE.

Referring toFIG.30, the UE accesses the base station through a random access procedure (S300). The random access procedure has already been described above. The base station provides a higher layer signal for setting K2 min values to the UE (S301). For example, ‘minimumSchedulingOffsetK2’ may be provided through ‘PUSCH-Config’ used to set UE-specific PUSCH parameters, and ‘minimumSchedulingOffsetK2’ may include a list of K2 min values.

The base station transmits a third DCI including information indicating a change to K2 min to the UE in slot n of the scheduling cell (S302). The third DCI may be DCI format 0_1. The third DCI may be transmitted within the first three symbols of slot n or outside the first three symbols, and the Z value used to determine the application delay X may vary depending on where it is transmitted. This has already been described above. The third DCI may inform the change of K2 min through a 1-bit field. This has already been described above.

The UE determines the application delay value X related to the time to apply the changed K2 min (S303). As described above, the X value may be determined based on the current K0min of the scheduled cell, the SCS configurations of the scheduling cell and the scheduled cell, and a predetermined value dependent on the SCS configuration of the scheduling cell. For example, Equation 1 can be used.

The base station transmits a fourth DCI to which the changed K2 min is applied (a fourth DCI based on the changed K2 min) in slot n+X of the scheduling cell (S304). Thereafter, the PUSCH scheduled by the fourth DCI is received in the scheduled cell (S305). The time interval between the fourth DCI and the PUSCH must be equal to or greater than the changed K2 min. In the time interval, the UE may perform a sleep operation or a PDCCH decoding relaxation operation to save power.

Meanwhile, NR supports a plurality of numerologies (or a plurality of ranges of subcarrier spacing (SCS)) in order to support a variety of 5G services. For example, when SCS is 15 kHz, a wide area in traditional cellular bands is supported; when SCS is 30 kHz/60 kHz, a dense-urban, lower-latency, and wider-carrier bandwidth is supported; when SCS is 60 kHz or higher, a bandwidth greater than 24.25 GHz is supported to overcome phase noise.

NR frequency bands may be defined as frequency ranges of two types (FR1 and FR2). The values of the frequency ranges may be changed. For example, the frequency ranges of the two types (FR1 and FR2) may be as shown in Table 7. For convenience of description, FR1 of the frequency ranges used for an NR system may refer to a “sub 6 GHz range”, and FR2 may refer to an “above 6 GHz range” and may be referred to as a millimeter wave (mmW).

TABLE 7Frequency rangeCorresponding frequencydesignationrangeSubcarrier spacingFR1450 MHz-6000 MHz15, 30, 60 kHzFR224250 MHz-52600 MHz60, 120, 240 kHz

As illustrated above, the values of the frequency ranges for the NR system may be changed. For example, FR1 may include a band from 410 MHz to 7125 MHz as shown in Table 8. That is, FR1 may include a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, or the like) or greater. For example, the frequency band of 6 GHz (or 5850, 5900, 5925 MHz, or the like) or greater included in FR1 may include an unlicensed band. The unlicensed bands may be used for a variety of purposes, for example, for vehicular communication (e.g., autonomous driving).

TABLE 8Frequency rangeCorresponding frequencydesignationrangeSubcarrier spacingFR1410 MHz-7125 MHz15, 30, 60 kHzFR224250 MHz-52600 MHz60, 120, 240 kHz

FIG.31illustrates a vehicle or an autonomous driving vehicle applied to this specification. The vehicle or the autonomous driving vehicle may be configured as a mobile robot, a car, a train, a manned/unmanned aerial vehicle (AV), a ship, or the like.

Referring toFIG.31, the vehicle or the autonomous driving vehicle100may include an antenna unit108, a communication unit110, a control unit120, a driving unit140a, a power supply unit140b, a sensor unit140c, and an autonomous driving unit140d. The antenna unit108may be configured as apart of the communication unit110. Blocks110/130/140ato140dcorrespond to the blocks110/130/140inFIG.28, respectively.

The communication unit110may transmit and receive a signal (e.g., data, a control signal, or the like) to and from external devices, such as a different vehicle, a base station (e.g. a base station, a road-side unit, or the like), and a server. The control unit120may control elements of the vehicle or the autonomous driving vehicle100to perform various operations. The control unit120may include an electronic control unit (ECU). The driving unit140amay enable the vehicle or the autonomous driving vehicle100to run on the ground. The driving unit140amay include an engine, a motor, a power train, wheels, a brake, a steering device, and the like. The power supply unit140bsupplies power to the vehicle or the autonomous driving vehicle100and may include a wired/wireless charging circuit, a battery, and the like. The sensor unit140cmay obtain a vehicle condition, environmental information, user information, and the like. The sensor unit140cmay include an inertial measurement unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, an inclination sensor, a weight sensor, a heading sensor, a position module, vehicular forward/backward vision sensors, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illuminance sensor, a pedal position sensor, and the like. The autonomous driving unit140dmay implement a technology for maintaining a driving lane, a technology for automatically adjusting speed, such as adaptive cruise control, a technology for automatic driving along a set route, a technology for automatically setting a route and driving when a destination is set, and the like.

For example, the communication unit110may receive map data, traffic condition data, and the like from an external server. The autonomous driving unit140dmay generate an autonomous driving route and a driving plan on the basis of obtained data. The control unit120may control the driving unit140ato move the vehicle or the autonomous driving vehicle100along the autonomous driving route according to the driving plan (e.g., speed/direction control). During autonomous driving, the communication unit110may aperiodically/periodically obtain updated traffic condition data from the external server and may obtain surrounding traffic condition data from a neighboring vehicle. Further, during autonomous driving, the sensor unit140cmay obtain a vehicle condition and environmental information. The autonomous driving unit140dmay update the autonomous driving route and the driving plan on the basis of newly obtained data/information. The communication unit110may transmit information about a vehicle location, an autonomous driving route, a driving plan, and the like to the external server. The external server may predict traffic condition data in advance using AI technology or the like on the basis of information collected from vehicles or autonomous driving vehicles and may provide the predicted traffic condition data to the vehicles or the autonomous driving vehicles.

Claims disclosed in the present specification can be combined in various ways. For example, technical features in method claims of the present specification can be combined to be implemented or performed in an apparatus, and technical features in apparatus claims of the present specification can be combined to be implemented or performed in a method. Further, technical features in method claims and apparatus claims of the present specification can be combined to be implemented or performed in an apparatus. Further, technical features in method claims and apparatus claims of the present specification can be combined to be implemented or performed in a method.