Method for receiving downlink signal, user equipment, processing device, storage medium, method for transmitting downlink signal, and base station

Abstract

The UE may: receive a cell DRX configuration related to a first cell configured with a PUCCH resource; determining an active period in which uplink transmission of the first cell is not limited and an inactive period in which uplink transmission of the first cell is limited based on the cell DRX configuration related to the first cell; and performing PDCCH monitoring on a second cell using the first cell for PUCCH transmission based on the first cell being in the active period.

Description

TECHNICAL FIELD

[0001] The disclosure relates to a wireless communication system. BACKGROUND

[0002] Various technologies such as machine-to-machine (M2M) communication, machine type communication (MTC), and various devices requiring high data throughput (e.g., smart phones and tablet personal computers (PCs)) have emerged and are spreading. Accordingly, data throughput requiring processing in a cellular network is rapidly increasing. In order to meet such rapidly increasing data throughput, a carrier aggregation technology or a cognitive radio technology for efficiently employing more frequency bands and a multiple input multiple output (MIMO) technology or a multi-base station (BS) cooperation technology for increasing data capacity transmitted on limited frequency resources have been developed.

[0003] As more and more communication devices require greater communication capacity, enhanced mobile broadband (eMBB) communication relative to a conventional radio access technology (RAT) is required. In addition, massive machine type communication (mMTC) that provides various services anywhere, anytime by connecting multiple devices and objects to each other is a major issue to be considered in next-generation communication.

[0004] Communication system design considering services / user equipment (UEs) sensitive to reliability and latency is also being discussed. Introduction of next-generation RATs is being discussed considering eMBB communication, mMTC, ultra-reliable low-latency communication (URLLC), etc.

[0005] As the number of services / user equipment (UEs) that a network needs to support rapidly increases, the demand for not only UE power saving but also network energy saving gradually increases. SUMMARY

[0006] TECHNICAL PROBLEM

[0007] An object of the disclosure is to provide a method and procedure for network energy saving.

[0008] Another object of the disclosure is to provide a method and procedure for transmitting / receiving a downlink signal to implement network energy saving.

[0009] Another object of the disclosure is to provide a method and procedure for transmitting / receiving an uplink signal to implement network energy saving.

[0010] The objects to be achieved by the disclosure are not limited to those specifically described above, and other objects not described herein will be more clearly understood by persons skilled in the art from the following detailed description.

[0011] TECHNICAL SOLUTION

[0012] According to one aspect of this disclosure, a method is provided for a user equipment (UE) to receive downlink signals in a wireless communication system. The method may include the steps of: receiving a cell discontinuous reception (DRX) configuration for a first cell configured with physical uplink control channel (PUCCH) resources; determining an unrestricted active period and a restricted inactive period for uplink transmission on the first cell based on the cell DRX configuration for the first cell; and performing physical downlink control channel (PDCCH) monitoring on a second cell using the first cell for PUCCH transmission based on the first cell being in an active period.

[0013] According to another aspect of this disclosure, a UE is provided for receiving downlink signals in a wireless communication system. The UE includes: at least one transceiver; at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations. The operations may include: receiving a cell DRX configuration for a first cell configured with PUCCH resources; determining an unrestricted active period and a restricted inactive period for uplink transmission on the first cell based on the cell DRX configuration for the first cell; and performing PDCCH monitoring on a second cell using the first cell for PUCCH transmission based on the first cell being in an active period.

[0014] According to another aspect of this disclosure, a processing apparatus in a wireless communication system is provided. The processing apparatus includes: at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations. The operations may include: receiving a cell DRX configuration for a first cell configured with PUCCH resources; determining, based on the cell DRX configuration for the first cell, an unrestricted uplink transmission activity period and a restricted uplink transmission inactivity period on the first cell; and performing PDCCH monitoring on a second cell using the first cell for PUCCH transmissions, based on the first cell being in an active period.

[0015] According to another aspect of this disclosure, a computer-readable storage medium is provided. The storage medium stores at least one program code including instructions that, when executed, cause at least one processor to perform operations, the operations including: receiving a cell DRX configuration for a first cell configured with PUCCH resources; determining an unrestricted active period and a restricted inactive period for uplink transmission on the first cell based on the cell DRX configuration for the first cell; and performing PDCCH monitoring on a second cell using the first cell for PUCCH transmission based on the first cell being in an active period.

[0016] According to another aspect of this disclosure, a method is provided for transmitting downlink signals from a base station (BS) to a user equipment (UE) in a wireless communication system. The method may include the steps of: transmitting a cell DRX configuration for a first cell configured with PUCCH resources; determining an active period for unrestricted uplink reception and an inactive period for restricted uplink reception on the first cell based on the cell DRX configuration for the first cell; and performing PDCCH transmission on a second cell using the first cell for PUCCH reception based on the first cell being in an active period.

[0017] According to another aspect of this disclosure, a BS is provided for transmitting downlink signals to a UE in a wireless communication system. The BS includes: at least one transceiver; at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations. The operations may include: transmitting a cell DRX configuration for a first cell configured with PUCCH resources; determining an active period for unrestricted uplink reception and an inactive period for restricted uplink reception on the first cell based on the cell DRX configuration for the first cell; and performing PDCCH transmission on a second cell using the first cell for PUCCH reception, based on the first cell being in an active period.

[0018] In various aspects of this disclosure, the method of the UE or the operation in the UE, processing apparatus, or storage medium may include: performing Physical Downlink Shared Channel (PDSCH) reception scheduled on the second cell based on the first cell being in an active period. In various aspects of this disclosure, the method of the BS or the operation in the BS may include: performing PDSCH transmission scheduled on the second cell based on the first cell being in an active period.

[0019] In various aspects of this disclosure, the method of the UE or the operation in the UE, processing apparatus, or storage medium may include: not performing PDCCH monitoring on the second cell based on the first cell being in an inactive period. In various aspects of this disclosure, the method of the BS or the operation in the BS may include: not performing PDCCH transmission on the second cell based on the first cell being in an inactive period.

[0020] In various aspects of this disclosure, the method of the UE or the operation in the UE, processing apparatus, or storage medium may include: not performing PDSCH reception scheduled on the second cell based on the first cell being in an inactive period. In various aspects of this disclosure, the method of the BS or the operation in the BS may include: not performing PDSCH transmission scheduled on the second cell based on the first cell being in an inactive period.

[0021] In various aspects of this disclosure, in the method of the UE or in the operation of the UE, processing apparatus or storage medium, PDCCH monitoring of the second cell may not be performed during the inactive period of the first cell, regardless of whether there is a cell DRX configuration for the second cell. In various aspects of this disclosure, in the method of the BS or in the operation of the BS, PDCCH transmission for the second cell may not be performed during the inactive period of the first cell, regardless of whether there is a cell DRX configuration for the second cell.

[0022] In various aspects of this disclosure, the method of the UE or the operation in the UE, processing apparatus, or storage medium may include: postponing a first PUCCH transmission scheduled during an inactive period of the first cell until after the inactive period. In various aspects of this disclosure, the method of the BS or the operation in the BS may include: postponing a first PUCCH reception scheduled during an inactive period of the first cell until after the inactive period.

[0023] In various aspects of this disclosure, in a UE method or operation within a UE, processing apparatus, or storage medium, delaying the first PUCCH transmission until after an inactivity period may include sending the HARQ-ACK codebook within the first PUCCH transmission by attaching the HARQ-ACK codebook to another HARQ-ACK codebook scheduled after the inactivity period of the first cell. In various aspects of this disclosure, in a BS method or operation within a BS, delaying the first PUCCH reception until after an inactivity period may include receiving HARQ-ACK information from the first PUCCH transmission, where the HARQ codebook is attached to another HARQ-ACK codebook scheduled after the inactivity period of the first cell.

[0024] The solutions described above are merely some examples of this disclosure, and those skilled in the art can deduce and understand various examples of the technical features incorporated herein from the following detailed description.

[0025] Beneficial effects

[0026] According to the implementation of this disclosure, energy-saving methods and processes for networks, base stations (BS), and / or user equipment (UE) can be provided.

[0027] According to the implementation of this disclosure, methods and procedures for transmitting / receiving downlink signals can be provided to achieve energy savings for the network, BS, and / or UE.

[0028] According to the implementation of this disclosure, methods and procedures for transmitting / receiving uplink signals can be provided to achieve energy savings for the network, BS, and / or UE.

[0029] The effects of this disclosure are not limited to those specifically described above. Those skilled in the art will understand more clearly from the following detailed description other effects not described herein. Attached Figure Description

[0030] The accompanying drawings are included to provide a further understanding of this disclosure. The drawings illustrate examples of implementations of this disclosure and, together with the detailed description, serve to illustrate the implementations of this disclosure:

[0031] Figure 1 An example of a communication system 1 to which the implementation of this disclosure is applied is shown;

[0032] Figure 2 This is a block diagram illustrating an example of a communication device capable of performing the methods according to this disclosure;

[0033] Figure 3 Another example of a wireless device capable of implementing the embodiments of this disclosure is shown;

[0034] Figure 4 An example of a frame structure used in a wireless communication system based on the 3rd Generation Partnership Project (3GPP) is shown;

[0035] Figure 5 The resource grid showing the time slots;

[0036] Figure 6 The diagram illustrates the physical channels in a 3GPP-based communication system as an example wireless communication system, and the signal transmission / reception process using these physical channels.

[0037] Figure 7 The random access procedure applicable to the implementation of this disclosure is illustrated;

[0038] Figure 8Examples of Physical Downlink Shared Channel (PDSCH) Time Domain Resource Assignment (TDRA) via Physical Downlink Control Channel (PDCCH) and Physical Uplink Shared Channel (PUSCH) TDRA via PDCCH are shown.

[0039] Figure 9 This illustrates the HARQ-ACK transmission / reception process.

[0040] Figure 10 Discontinuous reception (DRX) operation is shown for implementations applicable to this disclosure;

[0041] Figure 11 This shows the configurations for long and short DRX cycles;

[0042] Figure 12 and Figure 13 This illustrates the UE operation cycle according to some implementations of this disclosure;

[0043] Figure 14 This illustrates the DL / UL signal reception / transmission process at a UE according to some implementations of this disclosure;

[0044] Figure 15 The diagram illustrates the DL / UL signal transmission / reception process at the BS according to some implementations of this disclosure. Detailed Implementation

[0045] In the following, implementations according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description given below with reference to the accompanying drawings is intended to illustrate exemplary implementations of the present disclosure, and not to show only implementations that can be implemented according to the present disclosure. The following detailed description includes specific details in order to provide a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that the present disclosure can be practiced without these specific details.

[0046] In some cases, known structures and devices may be omitted or shown in block diagram form, thereby focusing on the essential features of the structures and devices so as not to obscure the concepts of this disclosure. The same reference numerals will be used throughout this disclosure to refer to the same or similar parts.

[0047] The following technologies, devices, and systems can be applied to various wireless multiple access systems. For example, multiple access systems may include Code Division Multiple Access (CDMA) systems, Frequency Division Multiple Access (FDMA) systems, Time Division Multiple Access (TDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single-Carrier Frequency Division Multiple Access (SC-FDMA) systems, Multi-Carrier Frequency Division Multiple Access (MC-FDMA) systems, etc. CDMA can be implemented using radio technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented using radio technologies such as Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), and Enhanced Data Rate GSM Evolution (EDGE) (i.e., GERAN). OFDMA can be specifically implemented using radio technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and Evolved UTRA (E-UTRA). UTRA is part of the Universal Mobile Telecommunications System (UMTS), and the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is part of E-UMTS that uses E-UTRA. 3GPP LTE uses OFDMA on the downlink (DL) and SC-FDMA on the uplink (UL). LTE-Advanced (LTE-A) is an evolution of 3GPP LTE.

[0048] For ease of description, this disclosure will be given under the assumption that it applies to LTE and / or the new RAT (NR). However, the technical features of this disclosure are not limited thereto. For example, although the following detailed description is based on a mobile communication system corresponding to a 3GPP LTE / NR system, the mobile communication system is applicable to any other mobile communication system except for matters specific to the 3GPP LTE / NR system.

[0049] For any terms and techniques used in this disclosure that are not described in detail, reference may be made to 3GPP-based standard specifications (e.g., 3GPP TS 36.211, 3GPP TS 36.212, 3GPP TS 36.213, 3GPP TS 36.321, 3GPP TS 36.300, 3GPP TS 36.331, 3GPP TS 37.213, 3GPP TS 38.211, 3GPP TS 38.212, 3GPP TS 38.213, 3GPP TS 38.214, 3GPP TS 38.300, 3GPP TS 38.304, 3GPP TS 38.331, etc.).

[0050] In the examples of this disclosure described later, if the apparatus “assumes” something, this could mean that the channel transmitting entity transmits the channel in accordance with the corresponding “assumption.” This could also mean that the channel receiving entity receives or decodes the channel in a form consistent with that “assumption,” provided that the channel is transmitted in accordance with that “assumption.”

[0051] In this disclosure, a user equipment (UE) can be fixed or mobile. Each of various devices that transmit and / or receive user data and / or control information by communicating with a base station (BS) can be a UE. The term UE can be referred to as a terminal device, mobile station (MS), mobile terminal (MT), user terminal (UT), subscriber station (SS), radio device, personal digital assistant (PDA), wireless modem, handheld device, etc. In this disclosure, a BS refers to a fixed station that communicates with a UE and / or another BS and exchanges data and control information with the UE and another BS. The term BS can be referred to as an advanced base station (ABS), node B (NB), evolved node B (eNB), base transceiver system (BTS), access point (AP), processing server (PS), etc. Specifically, a BS for Universal Terrestrial Radio Access (UTRAN) is referred to as an NB, a BS for Evolved UTRAN (E-UTRAN) is referred to as an eNB, and a BS for New Radio Access Technology networks is referred to as a gNB. In the following, for ease of description, regardless of the type or version of the communication technology, NB, eNB, or gNB will be referred to as BS.

[0052] In this disclosure, a node refers to a fixed point capable of sending / receiving radio signals to / from a UE via communication with the UE. Various types of BSs can be used as nodes, regardless of their name. For example, BS, NB, eNB, picocell eNB (PeNB), home eNB (HeNB), repeater, transponder, etc., can be nodes. Alternatively, a node may not be a BS. For example, a Radio Remote Headend (RRH) or Radio Remote Unit (RRU) can be a node. Typically, RRHs and RRUs have a lower power level than the BS. Since RRHs or RRUs (hereinafter, RRH / RRU) are typically connected to the BS via dedicated lines such as fiber optic cables, cooperative communication between the RRH / RRU and the BS can be performed smoothly compared to cooperative communication between the BS connected via a radio link. Each node is equipped with at least one antenna. An antenna can refer to a physical antenna port or a virtual antenna or antenna array. A node can also be referred to as a point.

[0053] In this disclosure, a cell refers to a specific geographical area where one or more nodes provide communication services. Therefore, in this disclosure, communication with a specific cell can mean communication with a BS or node providing communication services to that specific cell. The DL / UL signal of a specific cell refers to the DL / UL signal from / to the BS or node providing communication services to that specific cell. A cell providing UL / DL communication services to a UE is specifically referred to as a serving cell. Furthermore, the channel state / quality of a specific cell refers to the channel state / quality of the channel or communication link generated between the BS or node providing communication services to the specific cell and the UE. In 3GPP-based communication systems, the UE can use the CRS transmitted on the Cell Specific Reference Signal (CRS) resource and / or the CSI-RS transmitted on the Channel State Information Reference Signal (CSI-RS) resource (assigned to the specific node by the antenna port of the specific node) to measure the DL channel state from the specific node.

[0054] 3GPP-based communication systems use the concept of cells to manage radio resources and distinguish between cells related to radio resources and cells in geographical areas.

[0055] A "cell" of a geographic area can be understood as the coverage area within which a node can use a carrier to provide service, and a "cell" of radio resources is associated with the bandwidth (BW) of the frequency range configured by the carrier. Since DL coverage (the range within which a node can transmit a valid signal) and UL coverage (the range within which a node can receive a valid signal from a UE) depend on the carrier carrying the signal, a node's coverage area can also be associated with the coverage area of ​​the "cell" of the radio resources used by that node. Therefore, the term "cell" can be used to sometimes indicate the service coverage area of ​​a node, at other times to indicate a radio resource, or at other times to indicate the range within which a signal using a radio resource can reach with available effective strength.

[0056] In 3GPP communication standards, the concept of a cell is used to manage radio resources. A “cell” associated with radio resources is defined by a combination of DL resources and UL resources (i.e., a combination of DL component carriers (CCs) and UL CCs). A cell can be configured solely by DL resources or by a combination of DL and UL resources. If carrier aggregation is supported, the link between the carrier frequencies of the DL resources (or DL ​​CCs) and the UL resources (or UL CCs) can be indicated by system information. For example, a combination of DL and UL resources can be indicated by a System Information Block Type 2 (SIB2) link. In this case, the carrier frequencies can be equal to or different from the center frequencies of the individual cells or CCs. When carrier aggregation (CA) is configured, the UE has only one Radio Resource Control (RRC) connection with the network. During RRC connection establishment / re-establishment / handover, a serving cell provides Non-Access Plane (NAS) mobility information. During RRC connection re-establishment / handover, a serving cell provides security input. This cell is called the primary cell (Pcell). A Pcell refers to the cell operating on the primary frequency on which the UE performs the initial connection establishment procedure or initiates the connection re-establishment procedure. Depending on the UE's capabilities, a secondary cell (Scell) can be configured to form a set of serving cells together with a Pcell. An Scell ​​can be configured after RRC connection establishment and is used to provide additional radio resources beyond those of a specific cell (SpCell). The carrier corresponding to the Pcell on the DL is called the Downlink Primary CC (DL PCC), and the carrier corresponding to the Pcell on the UL is called the Uplink Primary CC (UL PCC). The carrier corresponding to the Scell ​​on the DL is called the Downlink Secondary CC (DLSCC), and the carrier corresponding to the Scell ​​on the UL is called the Uplink Secondary CC (UL SCC).

[0057] In dual connectivity (DC) operation, the term Special Cell (SpCell) refers to the Pcell of the Primary Cell Group (MCG) or the primary / secondary cell (Pcell) of the Secondary Cell Group (SCG). The SpCell supports PUCCH transmission and contention-based random access and is always enabled. The MCG is a set of serving cells associated with the primary node (e.g., BS) and includes the SpCell (Pcell) and optionally one or more Scells. For a UE configured with DC, the SCG is a subset of serving cells associated with the secondary node and includes the PSCell and zero or more Scells. The PSCell is the primary Scell ​​of the SCG. For a UE in the RRC_CONNECTED state without a CA or DC configured, only one serving cell exists, consisting only of the Pcell. For a UE in the RRC_CONNECTED state with a CA or DC configured, the term serving cell refers to the set of cells including the SpCell and all Scells. In DC, two Media Access Control (MAC) entities are configured for the UE: one MAC entity for the MCG and one MAC entity for the SCG.

[0058] For a UE configured with a CA but not a DC, a Pcell PUCCH group (also called a primary PUCCH group) including Pcells and 0 or more Scells can be configured, and an Scell ​​PUCCH group (also called a secondary PUCCH group) including only Scells can be configured. For an Scell, an Scell ​​(hereinafter, PUCCH Scell) can be configured to transmit PUCCHs associated with the corresponding cell. The Scell ​​indicating the PUCCH Scell ​​belongs to the Scell ​​PUCCH group (i.e., the secondary PUCCH group) and performs PUCCH transmission of the relevant uplink control information (UCI) on the PUCCH Scell. If no PUCCH Scell ​​is indicated for an Scell, or if the cell indicating the PUCCH transmission for the Scell ​​is a Pcell, then the Scell ​​belongs to the Pcell PUCCH group (i.e., the primary PUCCH group) and performs PUCCH transmission of the relevant UCI on the Pcell. In the following, if the UE is configured with an SCG and some implementations of this disclosure related to PUCCH are applied to the SCG, the primary cell can refer to the PSCell of the SCG. If the UE is configured with a PUCCH Scell ​​and some implementations of this disclosure related to PUCCH are applied to the secondary PUCCH group, then the primary cell may refer to the PUCCH Scell ​​of the secondary PUCCH group.

[0059] In addition to the Pcell and PUCCH Scell, the UE can also be configured with a PUCCH-sSCell, which is the Scell ​​used for PUCCH cell handover. For example, the PUCCH-sSCell can be provided to the UE via the RRC parameter pucch-sSCell. A periodic cell handover pattern for PUCCH transmission can be provided to the UE via the RRC parameter pucch-sSCellPattern. Each bit of the pucch-sSCellPattern corresponds to a time slot configured according to the reference subcarrier spacing (SCS), and indicates the PCell or PUCCH-sSCell as the cell used for PUCCH transmission during the time slot configured by the reference SCS. The UE transmits PUCCH on cells not indicated for PUCCH transmission outside of the PCell and PUCCH-sSCell, without following the periodic cell handover pattern. When a UE is configured with a PUCCH cell handover based on a dynamic indication of the DCI format, the DCI format associated with the UE generating HARQ-ACK information may include a PUCCH cell indicator field indicating whether the PUCCH transmission with HARQ-ACK information from the UE is on the PCell or PUCCH-sSCell.

[0060] In this disclosure, the term PUCCH cell is used to refer to a cell configured with PUCCH resources. PCell, PUCCH Scell, or PUCCH-sSCell may correspond to a PUCCH cell.

[0061] In a wireless communication system, the UE receives information from the BS on the DL and transmits information to the BS on the UL. The information transmitted and / or received by the BS and UE includes data and various control information, and various physical channels exist depending on the type / purpose of the information transmitted and / or received by the UE and BS.

[0062] 3GPP-based communication standards define DL physical channels corresponding to resource elements carrying information originating from higher layers, and DL physical signals corresponding to resource elements used by the physical layer but not carrying information originating from higher layers. For example, the Physical Downlink Shared Channel (PDSCH), Physical Broadcast Channel (PBCH), Physical Multicast Channel (PMCH), Physical Control Format Indicator Channel (PCFICH), and Physical Downlink Control Channel (PDCCH) are defined as DL physical channels, and reference signals (RS) and synchronization signals are defined as DL physical signals. RS (also called pilot) represents a signal with a predefined special waveform known to both the BS and the UE. For example, demodulation reference signal (DMRS), channel state information RS (CSI-RS), and positioning reference signal (PRS) are defined as DL RS. 3GPP-based communication standards also define UL physical channels corresponding to resource elements carrying information originating from higher layers, and UL physical signals corresponding to resource elements used by the physical layer but not carrying information originating from higher layers. For example, the Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), and Physical Random Access Channel (PRACH) are defined as UL physical channels, and the DMRS for UL control / data signals and the SRS for UL channel measurements are defined, etc.

[0063] In this disclosure, PDCCH refers to the set of time-frequency resources (e.g., resource elements (REs)) carrying downlink control information (DCI), and PDSCH refers to the set of time-frequency resources carrying DL data. PUCCH, PUSCH, and PRACH refer to the set of time-frequency resources carrying UCI, the set of time-frequency resources carrying UL data, and the set of time-frequency resources carrying random access signals, respectively. In the following description, "UE transmits / receives PUCCH / PUSCH / PRACH" is used to mean the same as the UE transmitting / receiving UCI / UL data / random access signals on or through PUCCH / PUSCH / PRACH. Similarly, "BS transmits / receives PBCH / PDCCH / PDSCH" is used to mean the BS transmitting broadcast information / DCI / DL data on or through PBCH / PDCCH / PDSCH.

[0064] In this specification, radio resources (e.g., time-frequency resources) scheduled or configured by the BS for the UE to transmit or receive PUCCH / PUSCH / PDSCH may be referred to as PUCCH / PUSCH / PDSCH resources.

[0065] Because communication devices receive synchronization signals (SS), DMRS, CSI-RS, PRS, PBCH, PDCCH, PDSCH, PUSCH, and / or PUCCH in the form of radio signals on a cell, the communication device may not select and receive radio signals that only include specific physical channels or specific physical signals via a radio frequency (RF) receiver, or it may not select and receive radio signals without specific physical channels or specific physical signals via an RF receiver. In practice, the communication device receives radio signals on a cell via an RF receiver, converts the radio signals, which are RF band signals, into baseband signals, and then uses one or more processors to decode the physical signals and / or physical channels in the baseband signals. Therefore, in some implementations of this disclosure, not receiving physical signals and / or physical channels may mean that the communication device does not attempt to recover physical signals and / or physical channels from the radio signals, for example, it does not attempt to decode physical signals and / or physical channels, rather than that the communication device does not actually receive radio signals that include the corresponding physical signals and / or physical channels.

[0066] With an increasing number of communication devices requiring greater communication capacity, there is a need for eMBB communication relative to traditional radio access technologies (RATs). Furthermore, massive MTC (Medium-Terminal Communication) to provide various services anytime, anywhere by connecting multiple devices and objects to each other is a major issue to be considered in next-generation communications. In addition, communication system designs considering reliability and latency-sensitive services / UEs are also being discussed. The introduction of next-generation RATs is being discussed, taking into account eMBB communication, massive MTC, ultra-reliable low-latency communication (URLLC), etc. Currently, research on next-generation mobile communication systems after EPC is underway within 3GPP. In this disclosure, for convenience, the corresponding technology is referred to as New RAT (NR) or 5th Generation (5G) RAT, and systems using or supporting NR are referred to as NR systems.

[0067] Figure 1 An example of a communication system 1 to which the implementation of this disclosure is applied is shown. (Refer to...) Figure 1The communication system 1 applied to this disclosure includes wireless devices, a network, and a network. Here, a wireless device refers to a device that performs communication using RAT (e.g., 5G NR or LTE (e.g., E-UTRA)) and may be referred to as a communication / radio / 5G device. Wireless devices may include (but are not limited to) robots 100a, vehicles 100b-1 and 100b-2, extended reality (XR) devices 100c, handheld devices 100d, home appliances 100e, Internet of Things (IoT) devices 100f, and artificial intelligence (AI) devices / servers 400. For example, vehicles may include vehicles with wireless communication capabilities, autonomous vehicles, and vehicles capable of performing vehicle-to-vehicle communication. Here, vehicles may include unmanned aerial vehicles (UAVs) (e.g., drones). XR devices may include augmented reality (AR) / virtual reality (VR) / mixed reality (MR) devices and may be implemented in the form of head-mounted displays (HMDs), head-up displays (HUDs) installed in vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signage, vehicles, robots, etc. Handheld devices may include smartphones, smart tablets, wearable devices (e.g., smartwatches or smart glasses), and computers (e.g., laptops). Home appliances may include TVs, refrigerators, and washing machines. IoT devices may include sensors and smart meters. For example, the BS and network may also be implemented as wireless devices, and a particular wireless device may operate as a BS / network node relative to another wireless device.

[0068] Wireless devices 100a to 100f can connect to network 300 via BS 200. AI technology can be applied to wireless devices 100a to 100f, and wireless devices 100a to 100f can connect to AI server 400 via network 300. Network 300 can be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although wireless devices 100a to 100f can communicate with each other via BS 200 / network 300, wireless devices 100a to 100f can perform direct communication with each other (e.g., sidelink communication) without going through the BS / network. For example, vehicles 100b-1 and 100b-2 can perform direct communication (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). IoT devices (e.g., sensors) can perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0069] Wireless communication / connections 150a and 150b can be established between wireless devices 100a to 100f and BS 200, as well as between wireless devices 100a to 100f. Here, wireless communication / connections such as UL / DL communication 150a and sidelink communication 150b (or device-to-device (D2D) communication) can be established via various RATs (e.g., 5G NR). The wireless devices and the BS / wireless devices can transmit / receive radio signals to / from each other via wireless communication / connections 150a and 150b. For this purpose, at least a portion of various configuration information configuration processes for transmitting / receiving radio signals, various signal processing processes (e.g., channel coding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation processes can be performed based on various proposals of this disclosure.

[0070] Figure 2 This is a block diagram illustrating an example of a communication device capable of performing the methods according to this disclosure. (Refer to...) Figure 2 The first wireless device 100 and the second wireless device 200 can transmit and / or receive radio signals via various RATs (e.g., LTE and NR). Here, {first wireless device 100 and second wireless device 200} can correspond to Figure 1 {Wireless Device 100x and BS 200} and / or {Wireless Device 100x and Wireless Device 100x}.

[0071] The first wireless device 100 may include one or more processors 102 and one or more memories 104, and additionally include one or more transceivers 106 and / or one or more antennas 108. The processors 102 may control the memories 104 and / or the transceivers 106, and may be configured to implement the functions, processes, and / or methods described / presented below. For example, the processors 102 may process information in the memories 104 to generate first information / signals, and then transmit radio signals including the first information / signals via the transceivers 106. The processors 102 may receive radio signals including second information / signals via the transceivers 106, and then store the information obtained by processing the second information / signals in the memories 104. The memories 104 may be connected to the processors 102 and may store various information relating to the operation of the processors 102. For example, the memories 104 may execute some or all of the processes controlled by the processors 102 or store software code including commands for executing the processes and / or methods described / presented below. Here, processor 102 and memory 104 may be part of a communication modem / circuit / chip designed to implement RAT (e.g., LTE or NR). Transceiver 106 may be connected to processor 102 and transmit and / or receive radio signals via one or more antennas 108. Each transceiver 106 may include a transmitter and / or a receiver. Transceiver 106 may be used interchangeably with radio frequency (RF) units. In this disclosure, a wireless device may refer to a communication modem / circuit / chip.

[0072] The second wireless device 200 may include one or more processors 202 and one or more memories 204, and additionally include one or more transceivers 206 and / or one or more antennas 208. The processors 202 may control the memories 204 and / or the transceivers 206, and may be configured to implement the functions, processes, and / or methods described / presented below. For example, the processors 202 may process information in the memories 204 to generate a third information / signal, and then transmit a radio signal including the third information / signal via the transceivers 206. The processors 202 may receive a radio signal including a fourth information / signal via the transceivers 206, and then store the information obtained by processing the fourth information / signal in the memories 204. The memories 204 may be connected to the processors 202 and may store various information relating to the operation of the processors 202. For example, the memories 204 may execute some or all of the processes controlled by the processors 202 or store software code including commands for executing the processes and / or methods described / presented below. Here, processor 202 and memory 204 may be part of a communication modem / circuit / chip designed to implement RAT (e.g., LTE or NR). Transceiver 206 may be connected to processor 202 and transmit and / or receive radio signals via one or more antennas 208. Each transceiver 206 may include a transmitter and / or a receiver. Transceiver 206 may be used interchangeably with an RF unit. In this disclosure, a wireless device may refer to a communication modem / circuit / chip.

[0073] The wireless communication technologies implemented in the wireless devices 100 and 200 of this disclosure may include narrowband Internet of Things (IoT) for low-power communication, as well as LTE, NR, and 6G. For example, NB-IoT technology may be an example of low-power wide-area network (LPWAN) technology and implemented in standards such as LTE Cat NB1 and / or LTE Cat NB2. However, NB-IoT technology is not limited to the above names. Alternatively or additionally, the wireless communication technologies implemented in the wireless devices XXX and YYY of this disclosure may perform communication based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and is referred to by various names including enhanced machine-type communication (eMTC). For example, LTE-M technology may be implemented in at least one of the following standards: 1) LTE Cat 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-bandwidth limited (non-BL), 5) LTE-MTC, 6) LTE machine-type communication, and / or 7) LTE M, etc., but LTE-M technology is not limited to the above names. Additionally or alternatively, considering low-power communication, the wireless communication technology implemented in the wireless devices XXX and YYY of this disclosure may include at least one of ZigBee, Bluetooth, and LPWAN, but the wireless communication technology is not limited to the above names. For example, ZigBee technology can be used to create personal area networks (PANs) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and ZigBee technology may be referred to by various names.

[0074] The hardware elements of wireless devices 100 and 200 will be described in more detail below. One or more protocol layers may be implemented by (but are not limited to) one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as the Physical (PHY) layer, Medium Access Control (MAC) layer, Radio Link Control (RLC) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Resource Control (RRC) layer, and Service Data Adaptation Protocol (SDAP) layer). One or more processors 102 and 202 may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the functions, processes, proposals, and / or methods disclosed in this disclosure. One or more processors 102 and 202 may generate messages, control information, data, or information according to the functions, processes, proposals, and / or methods disclosed in this disclosure. One or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, processes, proposals, and / or methods disclosed in this disclosure, and provide the generated signals to one or more transceivers 106 and 206. One or more processors 102 and 202 may receive signals (e.g., baseband signals) and acquire PDUs, SDUs, messages, control information, data, or information from one or more transceivers 106 and 206 according to the functions, processes, proposals, and / or methods disclosed in this disclosure.

[0075] One or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. One or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, one or more application-specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field-programmable gate arrays (FPGAs) may be included in one or more processors 102 and 202. The functions, processes, proposals, and / or methods disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be configured to include modules, processes, or functions. Firmware or software configured to perform the functions, processes, proposals, and / or methods disclosed in this disclosure may be included in one or more processors 102 and 202 or stored in one or more memories 104 and 204 to be driven by one or more processors 102 and 202. The functions, processes, proposals, and / or methods disclosed in this disclosure may be implemented using firmware or software in the form of code, commands, and / or sets of commands.

[0076] One or more memories 104 and 204 may be connected to one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, code, commands, and / or instructions. One or more memories 104 and 204 may be configured with read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, hard disk drive, registers, cache memory, computer-readable storage media, and / or combinations thereof. One or more memories 104 and 204 may be located internally and / or externally to one or more processors 102 and 202. One or more memories 104 and 204 may be connected to one or more processors 102 and 202 via various technologies such as wired or wireless connections.

[0077] One or more transceivers 106 and 206 may transmit user data, control information, and / or radio signals / channels mentioned in the methods and / or operation flowcharts of this disclosure to one or more other devices. One or more transceivers 106 and 206 may receive user data, control information, and / or radio signals / channels mentioned in the functions, processes, proposals, methods, and / or operation flowcharts disclosed in this disclosure from one or more other devices. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and transmit and receive radio signals. For example, one or more processors 102 and 202 may perform control to enable one or more transceivers 106 and 206 to transmit user data, control information, or radio signals to one or more other devices. One or more processors 102 and 202 may perform control to enable one or more transceivers 106 and 206 to receive user data, control information, or radio signals from one or more other devices. One or more transceivers 106 and 206 may be connected to one or more antennas 108 and 208. One or more transceivers 106 and 206 may be configured to transmit and receive user data, control information, and / or radio signals / channels mentioned in the functions, processes, proposals, methods, and / or operation flowcharts disclosed in this disclosure via one or more antennas 108 and 208. In this disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106 and 206 may convert received radio signals / channels, etc., from RF band signals to baseband signals for processing by one or more processors 102 and 202. One or more transceivers 106 and 206 may convert user data, control information, radio signals / channels, etc., processed by one or more processors 102 and 202 from baseband signals to RF band signals. For this purpose, one or more transceivers 106 and 206 may include (analog) oscillators and / or filters.

[0078] Figure 3 Another example of a wireless device capable of implementing the embodiments of this disclosure is shown. (Refer to...) Figure 3 Wireless devices 100 and 200 can correspond to Figure 2 The wireless devices 100 and 200 are configured with various elements, components, units / parts, and / or modules. For example, each of the wireless devices 100 and 200 may include a communication unit 110, a control unit 120, a memory unit 130, and an additional component 140. The communication unit may include a communication circuit 112 and a transceiver 114. For example, the communication circuit 112 may include... Figure 2One or more processors 102 and 202 and / or one or more memories 104 and 204. For example, transceiver 114 may include Figure 2 The device comprises one or more transceivers 106 and 206 and / or one or more antennas 108 and 208. Control unit 120 is electrically connected to communication unit 110, memory 130, and add-on components 140, and controls the overall operation of the wireless device. For example, control unit 120 may control the electrical / mechanical operation of the wireless device based on programs / code / commands / information stored in memory unit 130. Control unit 120 may transmit information stored in memory unit 130 to an external source (e.g., other communication devices) via communication unit 110 through a wireless / wired interface, or store information received from an external source (e.g., other communication devices) via communication unit 110 in memory unit 130 via a wireless / wired interface.

[0079] The additional component 140 can be configured differently depending on the type of wireless device. For example, the additional component 140 may include at least one of a power supply unit / battery, an input / output (I / O) unit, a drive unit, and a computing unit. The wireless device can be configured according to (but is not limited to) a robot ( Figure 1 100a), vehicles ( Figure 1 100b-1 and 100b-2), XR device ( Figure 1 100c), handheld device ( Figure 1 100d), home appliances ( Figure 1 100e), IoT devices ( Figure 1 100f), digital broadcast UE, holographic devices, public safety devices, MTC devices, medical devices, fintech devices (or financial devices), security devices, climate / environment devices, AI servers / devices ( Figure 1 400), BS ( Figure 3 This can be achieved through 200 network nodes, etc. Wireless devices can be used in mobile or fixed locations depending on usage / service.

[0080] exist Figure 4In wireless devices 100 and 200, all elements, components, units / parts, and / or modules may be interconnected via wired interfaces, or at least a portion thereof may be wirelessly connected via communication unit 110. For example, in each of wireless devices 100 and 200, control unit 120 and communication unit 110 may be wired connected, and control unit 120 and first units (e.g., 130 and 140) may be wirelessly connected via communication unit 110. The various elements, components, units / parts, and / or modules within wireless devices 100 and 200 may also include one or more elements. For example, control unit 120 may be configured as a collection of one or more processors. As an example, control unit 120 may be configured as a collection of communication control processors, application processors, electronic control units (ECUs), graphics processing units, and memory control processors. As another example, memory 130 may be configured as random access memory (RAM), dynamic RAM (DRAM), read-only memory (ROM), flash memory, volatile memory, non-volatile memory, and / or combinations thereof.

[0081] In this disclosure, at least one memory (e.g., 104 or 204) may store instructions or programs, and when executed, these instructions or programs may cause at least one processor operatively connected to the at least one memory to perform operations according to some embodiments or implementations of this disclosure.

[0082] In this disclosure, a computer-readable (non-volatile) storage medium may store at least one instruction or program, and the at least one instruction or program, when executed by at least one processor, may cause the at least one processor to perform operations according to some embodiments or implementations of this disclosure.

[0083] In this disclosure, a processing apparatus or device may include at least one processor and at least one computer memory operatively connected to said at least one processor. The at least one computer memory may store instructions or programs, and when executed, these instructions or programs may cause the at least one processor operatively connected to the at least one memory to perform operations according to some embodiments or implementations of this disclosure.

[0084] In this disclosure, a computer program may include program code stored on at least one computer-readable (non-volatile) storage medium, and when executed, is configured to perform operations according to some implementation of this disclosure or to cause at least one processor to perform operations according to some implementation of this disclosure. The computer program may be provided in the form of a computer program product. A computer program product may include at least one computer-readable (non-volatile) storage medium.

[0085] The communication apparatus of this disclosure includes: at least one processor; and at least one computer memory operatively connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations according to examples of this disclosure described later.

[0086] Figure 4 An example of a frame structure used in a 3GPP-based wireless communication system is shown.

[0087] Figure 4 The frame structure described is merely exemplary, and the number of subframes, time slots, and symbols within a frame can vary. In an NR system, different sets of OFDM parameters (e.g., subcarrier spacing (SCS)) can be configured for multiple cells aggregated for a UE. Therefore, the (absolute time) duration of time resources comprising the same number of symbols (e.g., subframes, time slots, or transmission time intervals (TTI)) can be configured differently for the aggregated cells. Here, symbols may include OFDM symbols (or cyclic prefix-OFDM (CP-OFDM) symbols) and SC-FDMA symbols (or discrete Fourier transform-extended-OFDM (DFT-s-OFDM) symbols). In this disclosure, symbols, OFDM-based symbols, OFDM symbols, CP-OFDM symbols, and DFT-s-OFDM symbols are used interchangeably.

[0088] Reference Figure 5 In NR systems, UL and DL transmissions are organized into frames. Each frame has a T f =(△f max *N f / 100)*T c =10 ms duration and is divided into two half-frames, each 5 ms. The basic time unit of NR is T. c =1 / (△f max *N f ), where △f max =480*10 3 Hz and N f =4096. For reference, the basic time unit for LTE is T. s =1 / (△f ref *N f,ref ), where △f ref =15*10 3 Hz and N f,ref =2048. T s and T c Having a constant κ=T s / T c =64. Each half-frame consists of 5 subframes, and the duration T of a single subframe is...sf The duration is 1 ms. Subframes are further divided into time slots, and the number of time slots within a subframe depends on the subcarrier spacing. Each time slot comprises either 14 or 12 OFDM symbols based on the cyclic prefix. In normal CP, each time slot comprises 14 OFDM symbols, while in extended CP, each time slot comprises 12 OFDM symbols. The parameter set depends on the exponentially scalable subcarrier spacing Δf = 2. u *15 kHz. The following shows the number of OFDM symbols per time slot (N). slot symb ), the number of time slots per frame (N) frame,u slot ) and the number of time slots per subframe (N) subframe,u slot ).

[0089] [Table 1]

[0090] u N slot symb ]] N frame,u slot ]] N subframe,u slot ]]> 0 14 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16 5 14 320 32 6 14 640 64

[0091] The following table shows the subcarrier spacing Δf = 2 u *15 kHz, the number of OFDM symbols per time slot, the number of time slots per frame, and the number of time slots per subframe.

[0092] [Table 2]

[0093] u N slot symb ]]> N frame,u slot ]]> N subframe,u slot ]]> 2 12 40 4

[0094] For the subcarrier spacing configuration u, the time slots can be indexed in ascending order within the subframe as follows: n u s ∈{0, ..., n subframe ,u slot -1}, and indexed in ascending order within the frame as follows: n u s,f ∈{0, ..., n frame,u slot -1}.

[0095] Frequency Range Designation The resource grid for the time slots is shown. A time slot comprises multiple (e.g., 14 or 12) symbols in the time domain. For each parameter set (e.g., subcarrier spacing) and carrier, the common resource block (CRB) N is indicated by higher-layer signaling (e.g., RRC signaling). start,u grid N was defined first. size,u grid,x *N RB sc Subcarriers and N subframe,u symb A resource grid of OFDM symbols, where N size,ugrid,x N represents the number of resource blocks (RBs) in the resource grid, with the index x representing DL for downlinks and UL for uplinks. RB sc N is the number of subcarriers per RB. In 3GPP-based wireless communication systems, N... RB sc Typically, it is 12. For a given antenna port p, subcarrier spacing configuration u, and transmission link (DL or UL), there exists a resource grid. The carrier bandwidth N of the subcarrier spacing configuration u is given to the UE via higher-layer parameters (e.g., RRC parameters). size,u grid Each element in the resource grid used for antenna port p and subcarrier spacing configuration u is called a resource element (RE), and a complex symbol can be mapped to each RE. Each RE in the resource grid is uniquely identified by an index k in the frequency domain and an index l representing the symbol position relative to a reference point in the time domain. In NR systems, RBs are defined by 12 consecutive subcarriers in the frequency domain. In NR systems, RBs are classified into CRBs and physical resource blocks (PRBs). For subcarrier spacing configuration u, CRBs are numbered from 0 upwards in the frequency domain. The center of subcarrier 0 of CRB 0 in subcarrier spacing configuration u is equal to "point A", which serves as the common reference point for the RB grid. The PRBs of subcarrier spacing configuration u are defined within the bandwidth portion (BWP) and numbered from 0 to N. size,u BWP,i -1 is the number, where i is the number of BWPs. The PRB n in BWPi PRB With CRB n u CRB The relationship between n u PRB =n u CRB +N size,u BWP,i Given, where N size BWP,i The BWP is the CRB that starts relative to CRB 0. A BWP comprises multiple consecutive RBs in the frequency domain. For example, a BWP can be a BWP i on a given carrier with a given set of parameters u. i A subset of adjacent CRBs is defined. A carrier may include up to N (e.g., 5) BWPs. A UE may be configured to have one or more BWPs on a given component carrier. Data communication is performed via enabled BWPs, and a predetermined number of BWPs (e.g., one BWP) may be active on the component carrier only among the BWPs configured for the UE.

[0096] For each serving cell in the set of DL BWPs or UL BWPs, the network can configure at least an initial DL BWP and one (if the serving cell has an uplink) or two (if supplementary uplinks are used) initial UL BWPs. The network can configure additional UL and DL BWPs. For each DL BWP or UL BWP, the following parameters can be provided to the UE for the serving cell: i) SCS; ii) CP; iii) parameters generated by N. start BWP= Under the assumption of 275, the indicated offset RB set and length L RB The CRB N is provided by the RRC parameter locationAndBandwidth as the Resource Indicator Value (RIV). start BWP =O carrier +RB start The number N of adjacent RBs size BWP =L RB And the value O provided by the RRC parameter offsetToCarrier for SCS. carrier ; an index in the set of DL BWP or UL BWP; a set of BWP common parameters; and a set of BWP specific parameters.

[0097] Virtual Resource Blocks (VRBs) can be defined within a BWP and range from 0 to N. size,u BWP,i -1 index, where i represents the BWP number. VRBs can be mapped to PRBs based on interleaved or non-interleaved mappings. In some implementations, for non-interleaved VRB-to-PRB mappings, VRB n can be mapped to PRB n.

[0098] The NR band is defined as two types of frequency ranges, namely FR1 and FR2. FR2 is also known as millimeter wave (mmW). The following shows the frequency range that NR can operate in.

[0099] [Table 3]

[0100] Corresponding Frequency Range Subcarrier Spacing FR1 410 MHz - 7125 MHz 15, 30, 60 kHz FR2 24250 MHz - 52600 MHz 60, 120, 240 kHz Figure 6

[0101] Figure 7 This is a diagram illustrating the physical channels in a 3GPP-based communication system, which serves as an exemplary wireless communication system, and the signal transmission / reception process using these physical channels.

[0102] When the UE is powered on or disconnected from the wireless communication system, the UE searches for a cell to camp on and performs an initial cell search, involving synchronization with the BS in the cell (S11). For the initial cell search, the UE receives a synchronization signal block (SSB) (also known as an SS / PBCH block) from the BS. The SSB includes the primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH). The UE establishes synchronization with the BS and obtains information such as the cell identifier (ID) based on the PSS / SSS. The UE can obtain broadcast information in the cell based on the PBCH. The UE can receive a DL reference signal (RS) during the initial cell search to monitor the DL channel status.

[0103] After the initial cell search, the UE can camp on the cell. Subsequently, the UE can monitor the PDCCH in the cell and obtain more specific system information by receiving the PDSCH based on the DCI carried on the PDCCH (S12).

[0104] Subsequently, to establish a connection with the BS, the UE may perform a random access procedure (S13 to S16). During the random access procedure, for example, the UE may transmit a preamble on the PRACH (S13) and receive the PDCCH and a random access response (RAR) to the preamble on the PDSCH corresponding to the PDCCH (S14). If the UE fails to receive the RAR directed to the UE, the UE may attempt to retransmit the preamble. In the case of contention-based random access, the UE may transmit the PUSCH based on the UL resource allocation included in the RAR (S15) and perform a contention resolution procedure (S16) for receiving the PDCCH and the PDSCH corresponding to the PDCCH.

[0105] Following the above process, the UE can receive PDCCH / PDSCH from the BS (S17) and send PUSCH / PUCCH to the BS during normal UL / DL signal transmission (S18). The control information sent by the UE to the BS is usually referred to as uplink control information (UCI). UCI includes hybrid automatic repeat request acknowledgment / negative acknowledgment (HARQ ACK / NACK), scheduling request (SR), and channel state information (CSI). CSI includes channel quality indicator (CQI), precoding matrix indicator (PMI), and / or rank indicator (RI). Typically, UCI is sent on the PUCCH. However, when control information and data should be sent simultaneously, control information can be sent on the PUSCH. Additionally, the UE can send UCI aperiodically on the PUSCH when receiving a request / command from the network.

[0106] Figure 7 A random access procedure applicable to an implementation of this disclosure is shown. In particular, Figure 7(a) shows the four-step random access procedure. Figure 7 (b) shows the two-step random access procedure.

[0107] Random access procedures can be used for various purposes, including initial access, UL synchronization adjustment, resource allocation, handover, radio link reconfiguration after radio link failure, and location. Random access procedures are classified into contention-based procedures and dedicated (i.e., non-contention-based) procedures. Contention-based random access procedures are typically involved in initial access, while dedicated random access procedures are used for UL synchronization reconfiguration in cases of handover, DL data arrival at the network, and location. In a contention-based random access procedure, the UE randomly selects a random access (RA) preamble. Therefore, multiple UEs can transmit the same RA preamble simultaneously, requiring a subsequent contention resolution process. In a dedicated random access procedure, the UE uses an RA preamble uniquely assigned to it by the BS. Therefore, the UE can perform the random access procedure without conflicting with other UEs.

[0108] Reference Figure 7 (a) The contention-based random access procedure comprises the following four steps. The messages sent in steps 1 to 4 may be referred to as message 1 (Msg1) to message 4 (Msg4), respectively.

[0109] - Step 1: The UE sends the RA preamble on the PRACH.

[0110] - Step 2: The UE receives the RAR from the BS on the PDSCH.

[0111] Step 3: The UE sends UL data to the BS on the PUSCH. The UL data includes Layer 2 (L2) / Layer 3 (L3) messages.

[0112] - Step 4: The UE receives the contention resolution message from the BS on the PDSCH.

[0113] The UE can receive random access information from the BS in the system information. For example, the system information can provide information about the timing of the RACH associated with an SSB on the cell. The UE can select an SSB among those received on the cell whose Reference Signal Received Power (RSRP) based on the SSB measurement exceeds a threshold. The UE can then transmit an RA preamble on the PRACH associated with the selected SSB. For example, when the UE needs random access, the UE transmits Msg1 (e.g., a preamble) to the BS on the PRACH. The BS can identify each RA preamble by the time / frequency resource (RA timing (RO)) carrying the RA preamble and the preamble index (PI). Upon receiving the RA preamble from the UE, the BS transmits a RAR message to the UE on the PDSCH. To receive the RAR message, the UE monitors the L1 / L2 control channel (PDCCH) with a Cyclic Redundancy Check (CRC) masked with a Random Access-RNTI (RA-RNTI) within a pre-configured time window (e.g., ra-ResponseWindow), including scheduling information for the RAR message. The length of the RAR window can be configured by higher-layer signaling, and the RAR window can begin at a specific time after the PRACH transmission (e.g., at the first symbol of the earliest control resource set (CORESET) in the Type 1 PDCCH common search space, starting at least one symbol after the PRACH timing corresponding to the PRACH transmission). When scheduling information is received on a PDCCH masked with RA-RNTI, the UE can receive the RAR message on the PDSCH indicated by the scheduling information. The UE then checks whether a RAR pointing to the UE exists in the RAR message. The existence of a RAR pointing to the UE can be determined by checking whether the random access preamble ID (RAPID) of the preamble sent by the UE exists. The index of the preamble sent by the UE can be the same as the RAPID. The RAR includes the index of the corresponding RA preamble, UL synchronization timing offset information (e.g., timing advance command (TAC)), UL scheduling information transmitted with Msg3 (e.g., UL permission), and UE temporary identification information (e.g., temporary-C-RNTI (TC-RNTI)). Upon receiving the RAR, the UE sends Msg3 on the PUSCH based on the UL scheduling information and timing offset value in the RAR. Msg3 may include the UE's ID (or global ID). Additionally, Msg3 may include RRC connection request information for initial network access (e.g., an RRCSetupRequest message). After receiving Msg3, the BS sends a contention resolution message (i.e., Msg4) to the UE. When the UE receives the contention resolution message and the contention is successfully resolved, the TC-RNTI changes to the C-RNTI. Msg4 may include the ID of UE / RRC connection-related information (e.g., an RRCSetup message).When the information sent in Msg3 does not match the information received in Msg4, or when the UE does not receive Msg4 within a predetermined time, the UE can determine that the contention resolution has failed and retransmit Msg3.

[0114] The Dedicated Random Access Procedure comprises the following three steps. The messages sent in steps 0 through 2 may be referred to as Msg0 through Msg2, respectively. The BS can trigger the Dedicated Random Access Procedure via a PDCCH (hereinafter referred to as the PDCCH command) serving the purpose of transmitting the command RA preamble.

[0115] - Step 0: The BS assigns the RA preamble to the UE via dedicated signaling.

[0116] - Step 1: The UE sends the RA preamble on the PRACH.

[0117] - Step 2: The UE receives the RAR from the BS on the PDSCH.

[0118] Steps 1 and 2 of the dedicated random access procedure can be the same as steps 1 and 2 of the contention-based random access procedure.

[0119] NR systems may require lower latency than traditional systems. In particular, for latency-sensitive services such as URLLC, a four-step random access procedure may not be preferred. Various scenarios within NR systems may require low-latency random access procedures. When the implementation of this disclosure is implemented together with the random access procedure, the implementation of this disclosure can be implemented together with the following two-step random access procedure to reduce the latency involved in the random access process.

[0120] Reference Figure 8 (b) The two-step random access procedure can be performed in two steps: a MsgA transmission from the UE to the BS and a MsgB transmission from the BS to the UE. The MsgA transmission may include the transmission of the RA preamble on the PRACH and the transmission of the UL payload on the PUSCH. In the MsgA transmission, the PRACH and PUSCH may be transmitted in time division multiplexing (TDM). Alternatively, in the MsgA transmission, the PRACH and PUSCH may be transmitted in frequency division multiplexing (FDM).

[0121] Upon receiving MsgA, the BS may send MsgB to the UE. MsgB may include a RAR for the UE. After sending MsgA, the UE monitors for a response from the network within a time window used to monitor the RAR in order to perform a two-step random access procedure. The length of this time window may be configured by higher-layer signaling, and the time window may begin at a specific timing after the transmission of MsgA (e.g., at least one symbol after the last symbol of the PUCCH timing corresponding to the transmission of MsgA, in the first symbol of the earliest CORESET in the Type 1 PDCCH common search space).

[0122] An RRC connection request message (e.g., an RRCSetupRequest message) requesting the establishment of a connection between the RRC layer of the BS and the RRC layer of the UE can be included in the payload of MsgA. In this case, MsgB can be used to send RRC connection-related information (e.g., an RRCSetup message). Alternatively, an RRC connection request message (e.g., an RRCSetupRequest message) can be sent on the PUSCH based on the UL permission in MsgB. In this case, RRC connection-related information (e.g., an RRCSetup message) related to the RRC connection request can be sent on the PDSCH associated with the PUSCH transmission after the PUSCH transmission based on MsgB.

[0123] The physical channels available in 3GPP-based wireless communication systems will be described in detail below.

[0124] The PDCCH carries the DCI. For example, the PDCCH (i.e., the DCI) carries information about the transmission format and resource allocation of the downlink shared channel (DL-SCH), information about the resource allocation of the uplink shared channel (UL-SCH), paging information about the paging channel (PCH), system information about the DL-SCH, resource allocation information about control messages (e.g., Random Access Response (RAR) sent on the PDSCH) of layers higher than the physical layer in the UE / BS protocol stack (hereinafter, higher layers), transmission power control commands, and information about enabling / disabling configuration scheduling (CS), etc. The DCI that includes resource allocation information about the DL-SCH is called the PDSCH scheduling DCI, and the DCI that includes resource allocation information about the UL-SCH is called the PUSCH scheduling DCI. The DCI includes Cyclic Redundancy Check (CRC). The CRC is masked / scrambled with various identifiers (e.g., Radio Network Temporary Identifier (RNTI)) according to the owner and purpose of the PDCCH. For example, if the PDCCH is used for a specific UE, the CRS is masked with the UE identifier (e.g., Cell-RNTI (C-RNTI)). If the PDCCH is used for paging messages, the CRC is masked with the Paging RNTI (P-RNTI). If the PDCCH is used for system information (e.g., System Information Block (SIB)), the CRC is masked with the System Information RNTI (SI-RNTI). If the PDCCH is used for random access responses, the CRC is masked with the Random Access-RNTI (RA-RNTI).

[0125] When a PDCCH on one serving cell schedules a PDSCH or PUSCH on another serving cell, it is called cross-carrier scheduling. Cross-carrier scheduling with a Carrier Indicator Field (CIF) allows the PDCCH on one serving cell to schedule resources on another serving cell. When a PDSCH on one serving cell schedules a PDSCH or PUSCH on another serving cell, it is called self-carrier scheduling. When cross-carrier scheduling is used in a cell, the BS can provide the UE with information about the scheduling cell. For example, the BS can inform the UE whether the serving cell is scheduled by a PDCCH on another (scheduling) cell or by the serving cell itself. If the serving cell is scheduled by another (scheduling) cell, the BS can inform the UE which cell signals the DL assignment and UL authorization of the serving cell. In this disclosure, the cell carrying the PDCCH is called the scheduling cell, and the cell whose PUSCH or PDSCH transmission is scheduled by the DCI included in the PDCCH (i.e., the cell carrying the PUSCH or PDSCH scheduled by the PDCCH) is called the scheduled cell.

[0126] PDSCH is the physical layer DL channel for DL ​​data transmission. PDSCH carries DL data (e.g., DL-SCH transport blocks) and is modulated using techniques such as Quadrature Phase Shift Keying (QPSK), 16-Quadrature Amplitude Modulation (QAM), 64 QAM, 256 QAM, etc. Codewords are generated by encoding the transport block (TB). PDSCH can carry up to two codewords. Scrambling and modulation mapping can be performed for each codeword, and modulation symbols generated from each codeword can be mapped to one or more layers. Each layer, along with DMRS, is mapped to radio resources and generated as OFDM symbol signals. The OFDM symbol signals are then transmitted through the corresponding antenna ports.

[0127] For UL-SCH data transmission, the UE needs UL resources available to it; for DL-SCH data reception, the UE needs DL resources available to it. The BS assigns UL and DL resources to the UE through resource allocation. Resource allocation may include time-domain resource allocation (TDRA) and frequency-domain resource allocation (FDRA). In this disclosure, UL resource allocation is also referred to as UL licensing, and DL resource allocation is also referred to as DL assignment. UL licensing can be dynamically received by the UE on the PDCCH or in the RAR, or UL licensing can be semi-persistently configured to the UE from the BS via RRC signaling. DL assignment can be dynamically received by the UE on the PDCCH, or semi-persistently configured to the UE from the BS via RRC signaling.

[0128] On the UL, the BS can dynamically allocate UL resources to the UE via the PDCCH addressed to the temporary identifier (Cell Radio Network Temporary Identifier, C-RNTI). The UE monitors the PDCCH to detect possible UL licenses for UL transmission. The BS can allocate UL resources to the UE using configuration licenses (CG). Two types of configuration licenses are available: Type 1 and Type 2. In Type 1, the BS directly provides the configured UL licenses (including periodicity) via RRC signaling. In Type 2, the BS configures the periodicity of RRC-configured UL licenses via RRC signaling and can signal and enable or disable the configured UL licenses via the PDCCH addressed to the configuration scheduling RNTI (CS-RNTI). For example, in Type 2, the PDCCH addressed to the CS-RNTI indicates deactivation, and the corresponding UL license can be implicitly reused based on the periodicity configured via RRC signaling.

[0129] On the DL (Deep Node) architecture, the BS (Base Station) can dynamically allocate DL resources to the UE via the PDCCH (Programmable Node Distributor) addressed to the C-RNTI (Central Receiver Instruction). The UE monitors the PDCCH to detect potential DL assignments. The BS can allocate DL resources to the UE using semi-persistent scheduling (SPS). The BS can configure the periodicity of the configured DL assignments via RRC (Regulatory Relationship Control) signaling and signal to enable or disable the configured DL assignments via the PDCCH addressed to the CS-RNTI. For example, indicating until deactivation via the PDCCH addressed to the CS-RNTI implicitly reuses the corresponding DL assignment based on the periodicity configured via RRC signaling.

[0130] In this disclosure, a PDSCH based on DL SPS may be referred to as an SPS PDSCH, and a PUSCH based on UL Configuration License (CG) may be referred to as a CG PUSCH. A PDSCH dynamically scheduled by DCI carried on a PDCCH may be referred to as a Dynamically Licensed (DG) PDSCH, and a PUSCH dynamically scheduled by DCI carried on a PDCCH may be referred to as a DG PUSCH.

[0131] Figure 9 Examples of PDSCH TDRA caused by PDCCH and PUSCH TDRA caused by PDCCH are shown.

[0132] The DCI carried by the PDCCH for scheduling PDSCH or PUSCH includes a TDRA field. The TDRA field provides the row index m+1 and a value m for the PDSCH or PUSCH allocation table. A predefined default PDSCH time-domain allocation is applied as the PDSCH allocation table, or the PDSCH TDRA table configured by the BS via the RRC signal pdsch-TimeDomainAllocationList is applied as the PDSCH allocation table. Similarly, a predefined default PUSCH time-domain allocation is applied as the PUSCH allocation table, or the PUSCH TDRA table configured by the BS via the RRC signal pusch-TimeDomainAllocationList is applied as the PUSCH allocation table. The PDSCH TDRA table to be applied and / or the PUSCH TDRA table to be applied can be determined according to fixed / predefined rules (e.g., refer to 3GPPTS 38.214).

[0133] In the PDSCH time-domain resource configuration, each index row defines the DL assignment with the PDSCH slot offset K0, the start and length indicators SLIV (or the start position of the PDSCH in the direct slot (e.g., the start symbol index S) and the allocation length (e.g., the number of symbols L)), and the PDSCH mapping type. In the PUSCH time-domain resource configuration, each index row defines the UL license with the PUSCH slot offset K2, the start position of the PUSCH in the slot (e.g., the start symbol index S) and the allocation length (e.g., the number of symbols L), and the PUSCH mapping type. K0 for PDSCH and K2 for PUSCH indicate the difference between a slot with a PDCCH and a slot with a corresponding PDSCH or PUSCH. SLIV represents a joint indicator of the start symbol S relative to the start of the slot with the PDSCH or PUSCH and the number L of consecutive symbols counted from symbol S. There are two PDSCH / PUSCH mapping types: mapping type A and mapping type B. In the case of PDSCH / PUSCH mapping type A, DMRS is mapped to the PDSCH / PUSCH resource relative to the start of the time slot. Depending on other DMRS parameters, one or two symbols of the PDSCH / PUSCH resource can be used as DMRS symbols. For example, in the case of PDSCH / PUSCH mapping type A, according to RRC signaling, the DMRS is located in the third symbol (symbol #2) or the fourth symbol (symbol #3) in the time slot. In the case of PDSCH / PUSCH mapping type B, DMRS is mapped relative to the first OFDM symbol of the PDSCH / PUSCH resource. Depending on other DMRS parameters, one or two symbols starting from the first symbol of the PDSCH / PUSCH resource can be used as DMRS symbols. For example, in the case of PDSCH / PUSCH mapping type B, the DMRS is located at the first symbol allocated to the PDSCH / PUSCH. In this disclosure, the PDSCH / PUSCH mapping type may be referred to as a mapping type or a DMRS mapping type. For example, in this specification, PUSCH mapping type A may be referred to as mapping type A or DMRS mapping type A, and PUSCH mapping type B may be referred to as mapping type B or DMRS mapping type B.

[0134] The scheduling DCI includes an FDRA field that provides assignment information about the RBs used for PDSCH or PUSCH. For example, the FDRA field provides information about the cell used for PDSCH or PUSCH transmission to the UE, information about the BWP used for PDSCH or PUSCH transmission, and / or information about the RBs used for PDSCH or PUSCH transmission.

[0135] PUCCH is a physical layer UL channel used for uplink control information (UCI) transmission. PUCCH carries UCI. The types of UCI transmitted on PUCCH include Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) information, Scheduling Request (SR) information, and Channel State Information (CSI). UCI bits include HARQ-ACK information bits (if present), SR information bits (if present), Link Recovery Request (LRR) information bits (if present), and CSI bits (if present). In this disclosure, the HARQ-ACK information bits correspond to the HARQ-ACK codebook. Specifically, the bit sequence of the HARQ-ACK information bits arranged according to a predetermined rule is called the HARQ-ACK codebook.

[0136] PUCCH resources can be determined based on UCI type (e.g., A / N, SR, or CSI). PUCCH resources used for UCI transmission can be determined based on UCI (payload) size. For example, the BS can configure multiple PUCCH resource sets for the UE, and the UE can select a specific PUCCH resource set corresponding to a specific range of UCI (payload) sizes (e.g., UCI bit count).

[0137] The configuration of each PUCCH resource includes the PUCCH resource index, the starting PRB index, and the configuration of one of PUCCH formats 0 to 4. The BS configures the code rate for multiplexing HARQ-ACK, SR, and CSI reports within PUCCH transmissions using PUCCH formats 2, 3, or 4 via the higher-layer parameter maxCodeRate. The higher-layer parameter maxCodeRate determines how to feed back UCI on PUCCH resources of PUCCH formats 2, 3, or 4.

[0138] If the UCI type is SR or CSI, the PUCCH resources to be used for UCI transmission can be configured for the UE via higher-layer signaling (e.g., RRC signaling). If the UCI type is HARQ-ACK for semi-persistent scheduling (SPS) PDSCH, the PUCCH resources to be used for UCI transmission can be configured for the UE via higher-layer signaling (e.g., RRC signaling). On the other hand, if the UCI type is HARQ-ACK for PDSCH scheduled by DCI, the PUCCH resources to be used for UCI transmission can be scheduled by DCI.

[0139] In the case of DCI-based PUCCH resource scheduling, the BS can send a DCI to the UE on the PDCCH and indicate the PUCCH resources to be used for UCI transmission in a specific PUCCH resource set via an ACK / NACK Resource Indicator (ARI) in the DCI. The ARI can be used to indicate PUCCH resources used for ACK / NACK transmission and is also called a PUCCH Resource Indicator (PRI). Here, the DCI can be used for PDSCH scheduling, and the UCI may include HARQ-ACK for the PDSCH. The BS can configure a PUCCH resource set for the UE via (UE-specific) higher-layer (e.g., RRC) signaling that includes a larger number of PUCCH resources than the ARI can represent. The ARI can indicate a subset of PUCCH resources in the PUCCH resource set, and which PUCCH resource in the indicated subset to use can be determined based on implicit rules according to transmission resource information about the PDCCH (e.g., the starting CCE index of the PDCCH).

[0140] Figure 9 This illustrates the HARQ-ACK sending / receiving process.

[0141] Reference UE Discontinuous Reception (DRX) The UE can detect the PDCCH in time slot n. Next, the UE can receive the PDSCH in time slot n+K0 based on the scheduling information received via the PDCCH in time slot n, and then send a UCI via the PUCCH in time slot n+K1. In this case, the UCI includes a HARQ-ACK response to the PDSCH.

[0142] The DCI (e.g., DCI format 1_0 or DCI format 1_1) carried by the PDCCH used to schedule the PDSCH may include the following information.

[0143] - FDRA: FDRA indicates the set of RBs assigned to PDSCH.

[0144] - TDRA: TDRA indicates the DL assignment with respect to the PDSCH slot offset K0, the starting position (e.g., symbol index S) and length (e.g., number of symbols L) of the PDSCH in the slot, and the PDSCH mapping type. PDSCH mapping type A or PDSCH mapping type B can be indicated by TDRA. For PDSCH mapping type A, the DMRS is located in the third symbol (symbol #2) or fourth symbol (symbol #3) in the slot. For PDSCH mapping type B, the DMRS is allocated in the first symbol assigned to the PDSCH.

[0145] - PDSCH-to-HARQ_feedback timer indicator: This indicator points to K1.

[0146] If the PDSCH is configured to send a maximum of one TB, the HARQ-ACK response can consist of one bit. If the PDSCH is configured to send a maximum of two TBs, the HARQ-ACK response can consist of two bits when spatial binding is not configured, and one bit when spatial binding is configured. When the timing of HARQ-ACK transmission for multiple PDSCHs is specified as time slot n+K1, the UCI transmitted in time slot n+K1 includes HARQ-ACK responses for multiple PDSCHs.

[0147] In this disclosure, the HARQ-ACK payload consisting of one or more HARQ-ACK bits of the PDSCH can be referred to as the HARQ-ACK codebook. Depending on the HARQ-ACK payload determination scheme, the HARQ-ACK codebook can be classified as i) a semi-static HARQ-ACK codebook, ii) a dynamic HARQ-ACK codebook, and iii) a HARQ process-based HARQ-ACK codebook.

[0148] In the case of a semi-static HARQ-ACK codebook, parameters related to the size of the HARQ-ACK payload to be reported by the UE are semi-statically determined by (UE-specific) higher-layer (e.g., RRC) signals. The size of the HARQ-ACK payload in the semi-static HARQ-ACK codebook (e.g., the (maximum) HARQ-ACK payload (size) transmitted via a PUCCH in one slot) can be determined based on the number of HARQ-ACK bits corresponding to a combination (hereinafter, the bundled window) of all DL carriers (i.e., DL serving cells) configured for the UE and all DL scheduling slots (or PDSCH transmission slots or PDCCH monitoring slots) that can indicate the timing of HARQ-ACK transmission. That is, in a semi-static HARQ-ACK codebook scheme, the size of the HARQ-ACK codebook is fixed (to the maximum value), regardless of the actual amount of DL data scheduled. For example, the DL-granted DCI (PDCCH) includes PDSCH and HARQ-ACK timing information, and the PDSCH and HARQ-ACK timing information can have one of several values ​​(e.g., k). For example, when a PDSCH is received in time slot #m and the PDSCH and HARQ-ACK timing information in the DL-licensed DCI (PDCCH) used to schedule the PDSCH indicates k, the HARQ-ACK information for the PDSCH can be sent in time slot #(m+k). As an example, k∈{1, 2, 3, 4, 5, 6, 7, 8}. When HARQ-ACK information is sent in time slot #n, the HARQ-ACK information may include the maximum possible HARQ-ACK based on the bundling window. That is, the HARQ-ACK information for time slot #n may include the HARQ-ACK corresponding to time slot #(nk). For example, when k∈{1, 2,3, 4, 5, 6, 7, 8}, the HARQ-ACK information for slot #n may include HARQ-ACKs corresponding to slots #(n-8) to #(n-1), regardless of the actual DL data reception (i.e., the maximum number of HARQ-ACKs). Here, the HARQ-ACK information can be replaced by the HARQ-ACK codebook or the HARQ-ACK payload. Slots can be understood / replaced as candidate times for DL ​​data reception. As described in the example, the bundling window can be determined based on the HARQ-ACK slots using PDSCH and HARQ-ACK timing, and the PDSCH and HARQ-ACK timing set can have predefined values ​​(e.g., {1, 2, 3, 4, 5, 6, 7, 8}) or can be configured by higher-layer (RRC) signaling. A semi-static HARQ-ACK codebook is referred to as a Type 1 HARQ-ACK codebook. For a Type 1 HARQ-ACK codebook, the number of bits to be sent in the HARQ-ACK report is fixed and may be large.If many cells are configured, but only a few are scheduled, the Type 1 HARQ-ACK codebook may be inefficient.

[0149] In the case of a dynamic HARQ-ACK codebook, the size of the HARQ-ACK payload that the UE needs to report can be dynamically changed through DCI, etc. The dynamic HARQ-ACK codebook is referred to as a Type 2 HARQ-ACK codebook. A Type 2 HARQ-ACK codebook can be considered an optimized HARQ-ACK feedback because the UE only sends feedback for the scheduled serving cell. However, under poor channel conditions, the UE may incorrectly determine the number of scheduled serving cells. To address this issue, a downlink assignment index (DAI) can be included as part of the DCI. For example, in a dynamic HARQ-ACK codebook scheme, the DL scheduling DCI may include counter-DAI (i.e., c-DAI) and / or total-DAI (i.e., t-DAI). Here, the DAI indicates the downlink assignment index and is used by the BS to inform the UE that a HARQ-ACK transmission sent or scheduled should include the PDSCH of its HARQ-ACK. Specifically, c-DAI is an index indicating the order among PDCCHs (hereinafter, DL-scheduled PDCCHs) carrying DL-scheduled DCIs, and t-DAI is an index indicating the total number of DL-scheduled PDCCHs up to the point where there is a current slot with a PDCCH having t-DAI.

[0150] In the case of a HARQ-ACK codebook based on HARQ processes, the HARQ-ACK payload is determined based on all HARQ processes of all configured (or enabled) serving cells in the PUCCH group. For example, the size of the HARQ-ACK payload that the UE will report using a HARQ-ACK codebook based on HARQ processes can be determined based on the number of all configured or enabled serving cells in the PUCCH group configured for the UE and the number of HARQ processes of the serving cells. A HARQ-ACK codebook based on HARQ processes is also known as a Type 3 HARQ-ACK codebook. A Type 3 HARQ-ACK codebook can be used for one-time feedback.

[0151] A CORESET can be defined and / or configured as the set of time-frequency resources that the UE can monitor for PDCCH. A CORESET has a duration of one to three OFDM symbols and includes a set of PRBs. The PRBs included in the CORESET and the CORESET duration can be provided to the UE via higher-layer (e.g., RRC) signaling. The UE can monitor the set of PDCCH candidates in the configured CORESET according to the corresponding search space set. In this disclosure, monitoring means decoding (blind decoding) of each PDCCH candidate based on the monitored DCI format.

[0152] The set of PDCCH candidates monitored by the UE is defined according to the PDCCH search space set. The search space set can be a common search space (CSS) set or a UE-specific search space (USS) set. Each CORESET configuration is associated with one or more search space sets, and each search space set is associated with a CORESET configuration.

[0153] The UE monitors the PDCCH candidate set in one or more CORESETs on the active DLBWP of each enabled serving cell configured with PDCCH monitoring, based on the corresponding search space set. Monitoring means receiving each PDCCH candidate and decoding it according to the monitored DCI format.

[0154] The UE can monitor PDCCH candidates in one or more SS sets within a time slot, depending on the configuration of the CORESET / SS set. The timing of monitoring PDCCH candidates (e.g., time / frequency resources) is defined as the PDCCH (monitoring) timing. One or more PDCCH (monitoring) timings can be configured within a time slot.

[0155] Figure 10

[0156] To reduce power consumption, the UE uses DRX. A UE operating on DRX repeatedly turns its receive operation on and off. The characteristics of DRX for reducing unnecessary power consumption in the UE are as follows. For DRX, there are separately defined structures: one for UEs in the RRC_IDLE state where an RRC connection has not yet been established between the UE and the BS (hereinafter referred to as I-DRX), and one for UEs in the RRC_CONNECTED state where an RRC connection has been established between the UE and the BS (hereinafter referred to as C-DRX). Both DRX structures are designed to define periodic intervals (e.g., active time or on-duration period) at which the UE can expect to receive DL signals, thus reducing unnecessary power consumption in other periods. In particular, in the case of C-DRX, the start position of the on-duration period is periodically defined according to the NR Rel-16 specification. In this case, the size of the configured period (i.e., the DRX cycle) can be determined / configured by higher-level signaling such as RRC signaling provided by the BS to the UE.

[0157] Figure 10 This illustrates discontinuous reception (DRX) operation. Specifically, Figure 10 The DRX loop for a UE in the RRC_CONNECTED state is shown.

[0158] Reference Figure 10The DRX cycle includes an on-duration period and a DRX opportunity. The DRX cycle defines the time interval between periodic repetitions of the on-duration period, followed by a possible inactivity period. The on-duration period is the time period during which the UE monitors the PDCCH. When the UE is configured with DRX, it performs PDCCH monitoring during the on-duration period. When the UE successfully detects a PDCCH during the PDCCH monitoring period, it starts an inactivity timer and remains awake. Conversely, when the UE fails to detect any PDCCH during the PDCCH monitoring period, it transitions to a sleep state after the on-duration period. Therefore, when DRX is configured, the UE can perform PDCCH monitoring / reception discontinuously in the time domain within the procedures and / or methods according to the implementation of this disclosure. For example, when DRX is configured, the PDCCH reception timing (e.g., time slots with a PDCCH search space) can be configured discontinuously according to the DRX configuration in this disclosure. Conversely, when DRX is not configured, the UE can perform PDCCH monitoring / reception continuously in the time domain. For example, when DRX is not configured, the timing of PDCCH reception can be configured continuously in this disclosure (e.g., time slots with PDCCH search space). Regardless of whether DRX is configured, PDCCH monitoring can be restricted during the time period configured as a measurement interval. DRX configuration information is received via higher-layer (e.g., RRC) signaling, and DRX on / off is controlled via DRX commands from the MAC layer. Once DRX is configured, the UE can perform PDCCH monitoring discontinuously, such as... Figure 10 As shown.

[0159] The table below describes the UE's DRX operation. Referring to the table, DRX configuration information is received via higher-layer signaling (e.g., RRC signaling), and DRX is enabled / disabled via DRX commands from the MAC layer. Once DRX is configured, the UE can perform PDCCH monitoring discontinuously, such as... Signal Type As shown.

[0160] [Table 4]

[0161] UE Procedure Step 1 RRC Signaling (MAC-CellGroupConfig) - Receive DRX configuration information Step 2 MAC CE ((Long) DRX Command MAC CE) - Receive DRX command Step 3 - Monitor PDCCH during ON duration of DRX cycle - Figure 11

[0162] MAC-CellGroupConfig includes the configuration information required to configure MAC parameters for a cell group. MAC-CellGroupConfig may also include DRX configuration information. For example, when defining a DRX, MAC-CellGroupConfig may include the following information.

[0163] The value of -drx-OnDurationTimer: Configures the duration at which the DRX cycle begins.

[0164] The value of -drx-SlotOffset: Configures the delay before starting drx-onDurationTimer.

[0165] The value of -drx-InactivityTimer: PDCCH indicates the duration following the PDCCH timing of a new UL or DL ​​transmission by a MAC entity.

[0166] The value of -drxRetransmissionTimerDL (per DL HARQ processing, excluding broadcast processing): configures the maximum duration until a DL retransmission is received.

[0167] The value of -drxRetransmissionTimerUL (per UL HARQ process): Configures the maximum duration until a permission to retransmit to the UL is received.

[0168] The value of -drx-HARQ-RTT-TimerDL (per DL HARQ processing, excluding broadcast processing): configures the maximum duration from receiving the initial DL transmission to receiving the DL assignment for HARQ retransmission.

[0169] The value of -drx-HARQ-RTT-TimerUL (per UL HARQ process): Configures the maximum duration from receiving permission for the initial UL transmission to receiving permission for a UL retransmission.

[0170] -drx-LongCycleStartOffset: Configures the long DRX cycle and drx-StartOffset, which defines the subframes at the start of the long and short DRX cycles.

[0171] -drx-ShortCycle (optional): Configures a short DRX cycle.

[0172] -drx-ShortCycleTimer (optional): Configures the duration for which the UE should follow a short DRX cycle. For example, the value of a multiple of the short DRX cycle can be configured via drx-CycleTimer. For instance, a value of n can correspond to n*drx-ShortCycle.

[0173] If a DRX group is active, the UE can perform PDCCH monitoring on the serving cells within the DRX group. In this case, a DRX group refers to a group of serving cells configured by RRC and having the same DRX active time. Here, active time refers to the total duration for which the UE monitors the PDCCH. Active time may include the duration of the DRX cycle being active, the time during which the UE performs continuous reception while the inactivity timer has not expired, and the time during which the UE performs continuous reception while waiting for a retransmission opportunity. For example, when configuring DRX, the active time of a serving cell in a DRX group includes i) the time during which the drx-onDurationTimer or drx-InactivityTimer configured for the DRX group is running; or ii) the time during which the drx-RetransmissionTimerDL or drx-RetransmissionTimerUL is running on any serving cell in the DRX group; or the ra-ContentionResoultionTimer or msgB-RsponseWindow is running; or the time during which a new transmission of C-RNTI indicating to the MAC entity to be sent to the UE is not received after a successful reception of a random access response to a random access preamble not selected by the MAC entity in a contention-based random access preamble.

[0174] One or more DRX groups can be configured for the UE via RRC signaling from the BS. For example, if two DRX groups are configured, each serving cell is uniquely assigned to one of the two DRX groups. DRX parameters drx-onDurationTimer and drx-InactivityTimer are configured separately for each DRX group. DRX parameters drx-SlotOffset, drx-RetransmissionTimerDL, drx-RetransmissionTimerUL, drx-LongCycleStartOffset, drx-ShortCycle (optional), drx-ShortCycleTimer (optional), drx-HARQ-RTT-TimerDL, and drx-HARQ-RTT-TimerUL are common to all DRX groups. Since each serving cell belongs to only one DRX group, and the DRX parameters drx-onDurationTimer and drx-InactivityTimer are configured for each DRX group, while other DRX parameters are common to the DRX group, it can be considered that the serving cell is associated with only one set of DRX parameters.

[0175] During the periodic on duration, the UE performs PDCCH monitoring to identify any UL or DL ​​transmission / reception to be performed. Upon receiving the PDCCH, the UE performs DL reception or UL transmission according to the PDCCH's indication. For UL, if data to be transmitted exists in the UL buffer, the UE can wake up and send a scheduling request (SR) regardless of C-DRX, even if it is in sleep mode. UEs in idle mode periodically perform paging monitoring. When the UE is not a paging target, it can re-enter sleep mode and operate in idle mode (idle mode DRX (i.e., I-DRX)). When it is said that the UE operates in sleep mode, this can mean that the UE performs SR transmissions "regardless of the active time determined by C-DRX" or "even during periods outside the active time determined by C-DRX". In C-DRX operation, a DRX cycle is a recurring time period that includes an on duration and an off duration. The length of the DRX cycle can be defined from the beginning of the on duration until the next on duration. DRX cycles can be classified as long DRX cycles and short DRX cycles. As the DRX cycle length increases, latency can increase because when the BS has a PDSCH to send to the UE immediately after the end of a specific on-time duration, the BS must wait until the UE's next on-time duration. From the BS's perspective, since the UE does not send periodic CSI (P-CSI) or sounding reference signals (SRS) during the off-time period, the BS can allocate these resources (i.e., resources used for P-CSI or SRS transmission) to other UEs, thereby increasing resource utilization. The BS can also switch to power-saving mode during the UE's off-time period to conserve energy.

[0176] Figure 11 This shows the configurations for long and short DRX cycles. Specifically, Figure 11 This shows the case where drx-ShortCycleTimer is set to 2.

[0177] The BS can configure a long DRX cycle and an additional short DRX cycle shorter than the long DRX cycle. If no short DRX cycle is configured, the UE can follow the long DRX cycle. When a short DRX cycle is configured, the BS can set the duration of the long DRX cycle to a positive integer multiple of the short DRX cycle. The same onDurationTimer value can be configured for both long and short DRX cycles. If there is no data activity during the on-duration duration of the long DRX cycle (e.g., no PDCCH received), the UE follows the long DRX cycle as if no short DRX cycle were configured. If there is data activity during the on-duration duration of the long DRX cycle, for example, while drx-onDurationTimer is running, the UE switches to a short DRX cycle and follows it for a specific time period (e.g., while drx-ShortCycleTimer is running). In this case, the start of the on-duration duration in the short DRX cycle is determined by drx-StartOffset and drx-SlotOffset, just as in the long DRX cycle. (See reference...) Network Energy Savings and Cell DRX / DTX If there is no data activity during the period when the UE follows a short DRX cycle, for example, if there is no data activity during the period defined by drx-ShortCycleTimer*drx-ShortCycle, the UE switches from a short DRX cycle with a duration of drx-ShortCycleTimer to a long DRX cycle.

[0178] The BS can instruct the UE to immediately enter DRX sleep mode and not operate in active mode until the active duration ends via the DRX command MAC control element (CE). For example, the BS can instruct the UE to end its current active time and immediately enter a DRX cycle. When the UE is only configured with a long DRX cycle, it can operate in a long DRX cycle (based on the DRX command MAC CE). When both long and short DRX cycles are configured for the UE, the UE immediately enters a short DRX cycle after receiving the DRX command MAC CE. Furthermore, when the BS provides a long DRX command MAC CE, the UE can operate in a long DRX cycle even if a short DRX cycle is configured.

[0179] The BS can also adjust / change the start point of the long DRX cycle through the RRC parameter drx-LongCycleStartOffset, which is used to configure the long DRX cycle, and drx-SlotOffset, which defines the subframe at the start of the long and short DRX cycles. The value of the RRC parameter drx-LongCycleStartOffset is defined in milliseconds so that the long DRX cycle can start at the slot boundary. Additionally, another RRC parameter, drx-SlotOffset, can be used to configure the start point of the on-duration with slot-level granularity. In this case, it is defined as the relative position of the on-duration by applying the slot offset indicated by (drx-SlotOffset) to the reference point indicated by drx-LongCycleStartOffset.

[0180] Compared to continuous monitoring of the PDCCH (e.g., in every time slot), the UE can save energy by waking up only during the active duration to monitor the PDCCH sent to it according to the C-DRX configuration. Furthermore, when the BS has no data to send to the UE during the upcoming active duration, the BS can save even more battery power by sending a Wake-Up Signal (WUS) before the start of the UE's active duration, thus indicating that waking up is not required during the active duration (i.e., no need to initiate the onDurationTimer). In this case, when the BS has no data to send to / receive from a UE with C-DRX configuration during the upcoming active duration, the BS can instruct the UE not to wake up during that active duration by sending a WUS that can be transmitted in DCI format 2_6 (used to notify one or more UEs of power-saving information outside of DRX active time) at a WUS timing configured before the active duration. Upon receiving the WUS (e.g., a wake-up indication via DCI format 2_6), the UE can remain in sleep mode without transitioning to active mode, thus saving even more energy.

[0181] Figure 12

[0182] Due to its potential contribution to building environmentally friendly networks by reducing carbon emissions and cutting communication operators' operating expenses (OPEX), network energy efficiency is being significantly considered in wireless communication systems, including those of 3GPP. In particular, with the increasing demand for high transmission rates following the advent of 5G communications, network base stations (BSs) need to be equipped with a greater number of antennas and provide services across wider bandwidths and frequency bands. According to recent research, the energy cost of BSs has reached up to 20% of total OPEX. Due to this increased focus on BS energy efficiency, 3GPP NR Release 18 approved a new research project called the "Network Energy Efficiency Study." For example, to enhance energy efficiency in BS transmission and reception, this study investigates how to use potential support / feedback from UEs and potential UE support information to achieve more efficient transmission and / or reception operations dynamically and / or semi-statically in the time, frequency, spatial, and power domains with finer adaptive granularity based on one or more network energy efficiency techniques.

[0183] When a BS operates in Network Energy Saving (NES) mode for energy saving (ES), it means that the BS has been pre-configured to disable the transmission of specific DL signals (e.g., the BS's Discontinuous Transmission (DTX) cycle) for multiple shutdown periods, and dynamically instructs one of these shutdown periods to indicate that no DL signals are transmitted during a predefined time period, thus reducing the power consumption of the BS and UE. NES mode can refer to an operating mode that reduces the power consumption of the BS and UE by performing operations in the frequency domain (e.g., BWP handover and dynamic resource block (RB) adaptation), the spatial domain (e.g., semi-statically or dynamically disabling a specific BS receive antenna port to stop transmission and / or reception through it), and the time domain.

[0184] As described above, when a UE is in connected mode after its initial connection to the BS, it should continuously perform PDCCH monitoring to identify whether scheduled transmissions for it exist in the search space of its various configurations. However, when such scheduling does not occur continuously, the UE's battery may be rapidly depleted due to unnecessary PDCCH monitoring each time. Therefore, the BS can configure the UE to have on periods (on duration) for PDCCH monitoring and off periods when monitoring is not required. That is, the BS can configure C-DRX for the UE to save UE power. The UE's C-DRX can also help the BS save power. For example, since the BS does not need to send PDCCH to a particular UE during the C-DRX off period of a particular UE, the BS can use resources (e.g., radio resources during the UE's C-DRX off period) for other purposes or to achieve ES gain from DTX / DRX. However, since the UE can perform transmissions without restriction in pre-configured resources (e.g., SR, PUCCH, CG PUSCH, etc.) when needed, the BS should remain ready to receive these unexpected UL transmissions from the UE even during the off period. Furthermore, because C-DRX is configured in a UE-specific manner, DRX cycles or on / off periods are not aligned among UEs within a cell (or BS). Therefore, when a UE's on period is configured in time-division multiplexing (TDM), the BS will not sleep, as it must remain awake during each on period of the UE within the cell (or BS) to transmit PDCCH, making it difficult for the BS to anticipate ES gain.

[0185] Therefore, in some implementations of this disclosure, similar to UE C-DRX, the BS can save energy by disabling the transmission / reception of specific signals / channels during inactive periods via cell (specific) DTX / DRX configurations for recurring active and inactive periods. When a specific cell (e.g., a PCell carrying a PUCCH) enters an inactive period according to its cell DTX / DRX configuration, the transmission / reception operations on other cells (e.g., SCells) linked to it via CA (or DC) may differ from those without a cell DTX / DRX configuration. Several implementations of this disclosure are described below regarding the transmission / reception operations on other cells associated with a specific cell when the specific cell performs a cell DTX / DRX operation (i.e., when the BS performs a cell DTX / DRX operation on the specific cell).

[0186] In the following description, UE DRX or C-DRX and I-DRX refer to discontinuous reception from the UE's perspective. Cell DRX refers to discontinuous reception from the BS's perspective, while cell DTX refers to discontinuous transmission from the BS's perspective. From the UE's perspective, cell DRX can mean disabling UL transmission, and cell DTX can mean disabling DL reception.

[0187] To reduce the activity time of DL transmission / UL reception by the BS, the UE can be configured with periodic cell DTX / DRX patterns (i.e., active and inactive periods). The cell DTX / DRX pattern can be shared by all UEs within the cell. Periodic cell DTX patterns can be configured for individual serving cells via RRC. The BS can configure cell-only DTX, cell-only DRX, or both for a cell. Cell DTX and cell DRX patterns can be configured and enabled individually. Up to N cell DTX / DRX patterns can be configured per MAC entity for different serving cells, where N is a predefined value. Cell DTX / DRX can be enabled / disabled via RRC signaling or L1 group common signaling (e.g., signaling via group common PDCCH).

[0188] The BS can control cell DTX and cell DRX operations by providing cell DTX / DRX configuration via RRC signaling. For example, through cell DTX / DRX configuration, the BS can provide RRC parameters related to the active period at the start of a cell DTX / DRX cycle (e.g., a cell DTX / DRX enable duration timer), the subframe at the start of the cycle, the delay before the start of the active period, and the cell DTX / DRX cycle period (i.e., the cell DTX / DRX periodicity). The active period in cell DTX / DRX can be the period during which the UE waits to receive a PDCCH or SPS and transmits an SR or CG. Cell DTX / DRX cycling specifies that the active period repeats periodically following the inactive period. The active period and cycle parameters can be common to both cell DTX and cell DRX. The BS can configure C-DRX and cell DTX / DRX to at least partially overlap between the UE's C-DRX enable period and the cell DTX / DRX active period. For example, the BS can configure the UE's C-DRX periodicity to be an integer multiple of the cell DTX / DRX periodicity, and vice versa.

[0189] Cell DTX operation affects the UE's monitoring activity of PDCCH and configured DL assignments under RRC_CONNECTED. For a serving cell with cell DTX configured and enabled, the UE (e.g., the UE's MAC entity) monitors the PDCCH on the serving cell when the serving cell is in a cell DTX activity period. The serving cell's cell DTX activity period may include the time period for running a cell DTX / DRX enable duration timer for the serving cell. For example, for a serving cell with cell DTX configured and enabled, when the serving cell is not in a cell DTX activity period, the UE (e.g., the UE's MAC entity) will not monitor the PDCCH on the serving cell and will not receive transport blocks on the serving cell according to the configured DL assignments of SPS (i.e., SPS PDSCH reception is not performed), regardless of whether the UE is in a UE C-DRX activity period.

[0190] Cell DRX operation control for UEs in RRC_CONNECTED state includes SR and UL-permitted transmission activity configuration. In some cases, when cell DRX is configured and enabled for a serving cell, the UE (e.g., the UE's MAC entity) can, in principle, only perform CG PUSCH and PUCCH transmissions on the serving cell during cell DRX active periods (if the serving cell is a PUCCH cell). For example, when the serving cell with cell DRX configured and enabled is in a cell DRX inactive period, the UE (e.g., the UE's MAC entity) does not transmit SR in the PUCCH resources used for SR (even if the serving cell is a PUCCH cell), does not report periodic CSI on the PUCCH (even if the serving cell is a PUCCH cell), and does not report the semi-persistent CSI configured on the serving cell's PUSCH. In other words, when cell DRX is configured and enabled for a serving cell, the UE will not perform transmissions in the serving cell's CG resources or transmit SR on the serving cell during DRX inactive periods.

[0191] <Implementation Method #1> When cell DTX / DRX is configured and operated (e.g., enabled) based on a cell or a set of cells, cell DTX / DRX is configured for a PUCCH cell, and the PUCCH cell enters a cell DTX / DRX inactivity period, a method is used to send / receive other cells (e.g., Scells) associated with the PUCCH cell (where the PUCCH cell can be i) a Pcell in the CA case, ii) a PScell ​​in the DC case, iii) a PUCCH Scell ​​in the CA case, or iv) an Scell ​​other than PCcell or PSCell available for PUCCH transmission in the case of PUCCH cell handover).

[0192] (1) When the PUCCH cell enters the cell DTX / DRX inactive period

[0193] - (1)-A. The UE does not perform PDSCH reception and corresponding PDCCH monitoring on other cells in the PUCCH group to which the PUCCH cell belongs (regardless of whether there are cell DTX / DRX configurations for other cells).

[0194] - (1)-B. Alternatively, the UE performs PDCCH monitoring and PDSCH reception as usual, but does not perform PUCCH transmission (i.e., disables or discards HARQ-ACK PUCCH transmission).

[0195] - (1)-C. Alternatively, the UE may postpone PUCCH transmission by attaching the (newly generated) subcodebook to the HARQ-ACK codebook configured for the corresponding PUCCH or perform it on another PUCCH cell in an active period (depending on its capabilities, there may be UEs that are applicable to this method and UEs that are not applicable to this method).

[0196] (2) When the scheduling cell responsible for scheduling enters the cell DTX / DRX inactive period, the method of not performing PDCCH monitoring on all scheduled cells that can be scheduled by the scheduling cell is not performed on the scheduling cell (regardless of whether there is a cell DTX / DRX configuration for the scheduled cells).

[0197] (3) When configuring and operating cell DTX / DRX for a PCell or PUCCH cell, apply the same cell DTX / DRX configuration (e.g., active / inactive pattern) to other cells in the PUCCH group or cell group to which the PCell or PUCCH cell belongs.

[0198] A BS can configure and operate cell DTX / DRX on a cell or cell group basis to save energy. As previously mentioned, cell DTX configuration and cell DRX configuration can be configured and operated separately. Similar to UE C_DRX, cell DTX / DRX configuration can configure parameters for periodicity, start timeslot / offset, and activation period, allowing active and inactive periods to repeat periodically in cells configured with cell DTX / DRX. During active periods, general BS transmission / reception is allowed, while during inactive periods, transmission / reception of specific signals / channels or all DL / UL transmission / reception can be disabled according to the cell DTX / DRX configuration. For example, based on cell DTX configuration, the BS will not perform scheduling via UE-specific dynamic clearance / assignment during inactive periods, and the UE will not perform PDCCH monitoring for dynamic clearance / assignment. When such cell DTX / DRX is configured and operated for a specific cell, it may affect not only the transmission / reception operation of that cell and the UE, but also the transmission / reception of other cells (e.g., SCells) associated via CA or DC and UEs belonging to other cells.

[0199] In a CA (Carrier Access Center), there may be a PCell that serves initial access, PUCCH transmission, and scheduling for other cells, as well as one or more SCells configured through the CA. Scheduling can be classified as self-carrier scheduling and cross-carrier scheduling. As previously mentioned, self-carrier scheduling means that the scheduling cell and the scheduled cell are the same, while cross-carrier scheduling means that the scheduling cell and the scheduled cell are different. In a CA environment, self-carrier scheduling is used by default unless additional configuration is provided; therefore, even for SCells, self-carrier scheduling is the default scheduling. For cross-carrier scheduling, the scheduling cell can be either a PCell or an SCell. That is, in cross-carrier scheduling, a PCell can schedule different SCells, or an SCell can schedule another SCell. Therefore, in some implementations of this disclosure, the scheduling cell and the scheduled cell can refer to the PCell and the SCell non-exclusively. As their names suggest, during cross-carrier scheduling, they can refer to the cell performing the scheduling and the scheduled cell, respectively. In a DC (Distributed Control Center), the cell group of the cell to which the UE initially connects is the MCG (Multi-Cell Group), and another cell group connected through the DC is the SCG (Multi-Cell Group). In each of the MCG and SCG, there may be a PSCell responsible for scheduling the PUCCH and other cells in the cell group, as well as one or more SCells connected to the PSCell via CA.

[0200] When configuring and operating cell DTX / DRX based on a cell or cell set, configuring cell DTX / DRX for a PUCCH cell, and the PUCCH cell enters an inactive period, it is necessary to consider methods for performing transmit / receive operations on other cells (e.g., SCells) associated with the PUCCH cell. This is because when the PUCCH cell is in an inactive period, the PUCCH of another cell configured to perform its PUCCH transmission on the PUCCH cell will not be transmitted during the inactive period. In this document, "PUCCH cell" may refer to i) PCell in CA case, ii) PSCell in DC case, iii) PUCCHSCell in CA case, or iv) SCell other than PCell or PSCell available for PUCCH transmission in PUCCH cell handover case, PUCCH-sSCell. In the following text, PCell, PSCell, PUCCH SCell, and PUCCH-sSCell are collectively referred to as PUCCH cell.

[0201] Figure 13 and Figure 12 This illustrates the UE operation cycle according to some implementations of this disclosure. Figure 13In the example, suppose cell DRX is configured for PUCCH cell A, but cell DRX is not configured for cell B that uses cell A for PUCCH transmissions. Therefore, cell B is active during both the active and inactive periods of cell DRX in cell A. Figure 12 In the example, it is assumed that cell DRX is configured for both PUCCH cell A and cell B that uses cell A for PUCCH transmission.

[0202] In some implementations of this disclosure, when a PUCCH cell enters a cell DTX / DRX inactive period (e.g., when cell DRX is configured for a PUCCH cell and the PUCCH cell enters a cell DRX period), it can be assumed that the UE does not perform PDSCH reception and corresponding PDCCH monitoring on other cells in the PUCCH group to which the PUCCH cell belongs. For the PUCCH cell, PDSCH reception and corresponding PDCCH monitoring can also be restricted. This method can be applied regardless of whether there are cell DTX / DRX configurations for other cells. See reference... Figure 13 and Figure 14When cell A is in a cell DRX inactive period, the UE will not perform PDSCH reception or PDSCH monitoring on cell B, even if cell B is in an active period. However, PDSCH monitoring and reception on cell B are permitted during the overlapping periods of cell B's active period and cell A's DRX active period. During periods where cell B's active period and cell A's DRX active period do not overlap, the UE will not perform PDSCH monitoring or reception on cell B, and the BS may consider this when performing PDSCH transmission and / or PDSCH scheduling on cell B. Restrictions on PDSCH monitoring of cell B can be applied to its scheduling cells, and restrictions on PDSCH reception scheduled on cell B can be applied to cell B. For example, if there is a scheduling cell C for cell B, and the HARQ-ACK feedback for PDSCH scheduled on cell B should be sent on cell A, then PDSCH monitoring and reception on cell C can also be performed during the overlapping periods of cell B's active period and cell A's DRX active period. When a PUCCH cell enters an inactive period according to its cell DTX / DRX configuration (specifically, a DRX inactive period where the BS disables reception on the cell), the BS may be unable to receive the PUCCH, even if the UE transmits it on the PUCCH cell, or the PUCCH transmission itself may be configured to be disabled during the inactive period. Furthermore, when a PUCCH cell is not allowed to perform PUCCH transmissions due to a cell DTX / DRX inactive period (i.e., the PUCCH cell does not carry PUCCH), even if the UE receives a PDSCH on a cell belonging to a PUCCH group that includes the PUCCH cell, or receives a PDCCH that schedules the PDSCH on a cell in the PUCCH group, the UE may be unable to transmit the PUCCH (carrying HARQ-ACK information) related to the PDSCH or the corresponding PDCCH, or the BS may be unable to receive the PUCCH. Therefore, when a PUCCH cell enters a cell DTX / DRX inactive period (especially a cell DRX inactive period), it may be efficient in terms of energy saving for other cells in the PUCCH group and UEs belonging to other cells, because the UE does not perform PDSCH reception and corresponding PDCCH monitoring for other cells associated with the PUCCH cell.

[0203] Alternatively, in some implementations of this disclosure, when a PUCCH cell enters a cell DTX / DRX inactive period (e.g., when a cell DRX is configured for a PUCCH cell and the PUCCH cell enters a cell DRX period), the UE may continue to perform PDCCH monitoring and PDSCH reception for other cells in the PUCCH group to which the PUCCH cell belongs, but will not perform PUCCH transmission. This is equivalent to disabling or discarding HARQ-ACK PUCCH transmission.

[0204] Alternatively, in another method, the UE may postpone PUCCH transmission, or perform PUCCH transmission on the other PUCCH cell by generating a (new) subcodebook from the HARQ-ACK information bits that cannot be transmitted due to the PUCCH cell being in an inactive period and attaching it to the HARQ-ACK codebook configured for another PUCCH cell in an active period (i.e., the original HARQ-ACK codebook scheduled / triggered to be transmitted on the PUCCH of the other PUCCH cell). Postponing PUCCH transmission means that when the original timing of the PUCCH transmission falls within or overlaps with an inactive period, the PUCCH is not transmitted at the original timing but is postponed. Furthermore, transmitting PUCCH on a PUCCH cell other than the original PUCCH cell where the UE should have performed PUCCH transmission can mean that a HARQ-ACK codebook that might not be transmitted due to a cell DTX / DRX inactivity period is added as a sub-codebook to the original HARQ-ACK codebook configured for another PUCCH cell (i.e., the HARQ-ACK codebook scheduled for the first transmission on that other PUCCH cell) and transmitted together. However, depending on their capabilities, there may be UEs that can support or apply this method and UEs that cannot support or apply this method.

[0205] In cross-carrier scheduling under CA conditions, there exists a scheduling cell (e.g., PCell or PSCell) responsible for scheduling and scheduled cells (e.g., SCell) being scheduled. When the scheduling cell enters a cell DTX / DRX inactive period, the UE will not perform PDCCH monitoring on all scheduled cells scheduled by the scheduling cell, regardless of whether there is a cell DTX / DRX configuration for the scheduled cells.

[0206] In some implementations of this disclosure, when configuring and operating cell DTX / DRX for a PCell or PUCCH cell, the BS and UE can also apply the same cell DTX / DRX configuration to other cells in the PUCCH group or cell group to which the corresponding cell belongs. In this case, cells in the same PUCCH group or cell group can operate with the same active / inactive time pattern, thereby maximizing ES gain.

[0207] <Implementation Method #2> A method for configuring the RAR window when cell DTX (or DRX) configuration is enabled for a cell where a RACH procedure (i.e., random access procedure) may occur, and the on / off pattern of a specific signal / channel repeats periodically on that cell.

[0208] When cell DTX / DRX configuration is enabled, the BS's pre-configured active and inactive periods are repeated. When PDCCH transmission is configured to be disabled during a DTX inactive period, the BS sends a PDCCH, which the UE does not expect to receive. However, when the UE sends a RACH during an active period, but the RACH's RAR window partially or completely overlaps with the BS's inactive period, the UE cannot receive the RAR. Therefore, the UE can execute the procedures defined in the standard for when it fails to receive the RAR.

[0209] In this scenario, it is undesirable in terms of energy saving and latency because the BS successfully receives the RACH but cannot transmit the RAR due to an inactive period according to the cell DTX / DRX configuration, as the UE or BS unnecessarily performs the procedures that should be performed when the UE actually fails to receive the RAR. Therefore, in some implementations of this disclosure, the RAR window that partially or completely overlaps with the cell DTX inactive period can be temporarily extended to include the next active period. This provides the BS with the opportunity to transmit the RAR upon successful RACH reception and allows the UE to continue the remaining RACH process without receiving the RAR. In some implementations of this disclosure, the RAR window extension can be accomplished by adding a pre-configured / agreed length to the basic RAR window length or by extending the basic RAR window length from the start of the next active period (i.e., restarting a new RAR window with the basic RAR window length from the start of the next active period).

[0210] The above implementation methods #1 and #2 can be applied individually or in combination.

[0211] When cell DTX / DRX is configured and enabled based on a cell or cell group, and the relevant PUCCH / scheduling cell enters an inactive period, the UE and BS can perform transmit / receive operations on other relevant cells (e.g., SCell) according to some implementations of this disclosure, thereby maximizing ES gain.

[0212] Figure 15 The process of receiving / transmitting DL / UL signals via a UE is illustrated according to some implementations of this disclosure.

[0213] The UE can perform operations in association with DL / UL signal reception / transmission according to some implementations of this disclosure. The UE may include: at least one transceiver; at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of this disclosure. A processing device for the UE may include: at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of this disclosure. A computer-readable (non-volatile) storage medium may store at least one computer program including instructions that, when executed by the at least one processor, cause the at least one processor to perform operations according to some implementations of this disclosure. A computer program or computer program product may include instructions recorded on at least one computer-readable (non-volatile) storage medium and, when executed, cause (at least one processor) to perform operations according to some implementations of this disclosure.

[0214] The method performed by the UE or the operation in the UE, processing apparatus, (non-transitory) computer-readable storage medium and / or computer program product may include: receiving a cell DRX configuration for a first cell configured with PUCCH resources (S1401); determining an active period for unrestricted uplink transmission and an inactive period for restricted uplink transmission on the first cell based on the cell DRX configuration for the first cell; and performing PDCCH monitoring on a second cell that uses the first cell for PUCCH transmission based on the first cell being in an active period (S1403).

[0215] In some implementations, the method or operation may include: performing PDSCH reception scheduled on the second cell based on the fact that the first cell is in an active period.

[0216] In some implementations, the method or operation may include: not performing PDCCH monitoring on the second cell based on the fact that the first cell is in an inactive period.

[0217] In some implementations, the method or operation may include: not performing PDSCH reception scheduled on the second cell based on the fact that the first cell is in an inactive period.

[0218] In some implementations, PDCCH monitoring of the second cell may not be performed during the inactive period of the first cell, regardless of whether there is a cell DRX configuration for the second cell.

[0219] In some implementations, the method or operation may include: postponing a first PUCCH transmission scheduled for an inactive period in a first cell until after the inactive period.

[0220] In some implementations, the method or operation may include: postponing the first PUCCH transmission until after an inactive period may include: sending the HARQ-ACK codebook within the first PUCCH transmission by attaching the HARQ-ACK codebook to another HARQ-ACK codebook scheduled to be sent after the inactive period of the first cell.

[0221] ​ The process of transmitting / receiving DL / UL signals via BS is illustrated according to some implementations of this disclosure.

[0222] The BS can be associated with DL / UL signal transmission / reception and perform operations according to some implementations of this disclosure. The BS may include: at least one transceiver; at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of this disclosure. A processing device for the BS may include: at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations according to some implementations of this disclosure. A computer-readable (non-volatile) storage medium may store at least one computer program including instructions that, when executed by the at least one processor, cause the at least one processor to perform operations according to some implementations of this disclosure. A computer program or computer program product may include instructions recorded on at least one computer-readable (non-volatile) storage medium and, when executed, cause (at least one processor) to perform operations according to some implementations of this disclosure.

[0223] The method performed by the BS, or the operation in the BS, processing apparatus, (non-transitory) computer-readable storage medium and / or computer program product, may include: transmitting a cell DRX configuration for a first cell configured with PUCCH resources (S1501); determining an active period for unrestricted uplink reception and an inactive period for restricted uplink reception on the first cell based on the cell DRX configuration for the first cell; and performing PDCCH transmission on a second cell that uses the first cell for PUCCH reception based on the first cell being in an active period (S1503).

[0224] In some implementations, the method or operation may include: performing PDSCH transmission scheduled on a second cell based on the first cell being in an active period.

[0225] In some implementations, the method or operation may include: not performing PDCCH transmission on the second cell based on the fact that the first cell is in an inactive period.

[0226] In some implementations, the method or operation may include: not performing PDSCH transmissions scheduled on the second cell based on the fact that the first cell is in an inactive period.

[0227] In some implementations, PDCCH transmissions for the second cell may not be performed during the inactive period of the first cell, regardless of whether there is a cell DRX configuration for the second cell.

[0228] In some implementations, the method or operation may include: postponing the reception of a first PUCCH scheduled for an inactive period in a first cell until after the inactive period.

[0229] In some implementations, the method or operation may include: delaying the first PUCCH reception until after an inactive period may include receiving HARQ-ACK information from the HARQ-ACK codebook within the first PUCCH reception, which is attached to another HARQ-ACK codebook scheduled for after the inactive period of the first cell.

[0230] Examples of this disclosure as described above have been presented to enable those skilled in the art to implement and practice this disclosure. Although the disclosure is described with reference to examples, various modifications and variations can be made to the examples of this disclosure by those skilled in the art. Therefore, this disclosure is not intended to be limited to the examples set forth herein, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

[0231] Implementations of this disclosure can be used in BS, UE, or other devices in wireless communication systems.

Claims

1. A method for receiving downlink signals by a user equipment (UE) in a wireless communication system, the method comprising the following steps: Receive cell discontinuous reception DRX configuration for the first cell configured with Physical Uplink Control Channel (PUCCH) resources; Based on the cell DRX configuration for the first cell, determine the active period of unrestricted uplink transmission and the inactive period of restricted uplink transmission on the first cell; as well as Based on the fact that the first cell is in the activity period, physical downlink control channel (PDCCH) monitoring is performed on the second cell that uses the first cell for PUCCH transmission.

2. The method according to claim 1, wherein the method comprises the following steps: Based on the fact that the first cell is in the activity period, the Physical Downlink Shared Channel (PDSCH) reception scheduled on the second cell is performed.

3. The method according to claim 1, wherein the method comprises the following steps: Since the first cell is in the inactive period, PDCCH monitoring is not performed on the second cell.

4. The method according to claim 1, wherein the method comprises the following steps: Since the first cell is in the inactive period, the PDSCH reception scheduled on the second cell is not performed.

5. The method according to claim 3, wherein, During the inactive period of the first cell, the PDCCH monitoring for the second cell is not performed, regardless of whether there is a cell DRX configuration for the second cell.

6. The method according to claim 1, wherein the method comprises the following steps: The first PUCCH transmission scheduled for the inactive period of the first cell is postponed until after the inactive period.

7. The method according to claim 6, wherein, The step of delaying the first PUCCH transmission until after the inactive period includes the following steps: The HARQ-ACK codebook is sent by attaching it to another HARQ-ACK codebook scheduled to be sent after the inactivity period of the first cell.

8. A user equipment (UE) for receiving downlink signals in a wireless communication system, the UE comprising: At least one transceiver; At least one processor; as well as At least one computer memory, operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform an operation. The operation includes: Receive cell discontinuous reception DRX configuration for the first cell configured with Physical Uplink Control Channel (PUCCH) resources; Based on the cell DRX configuration for the first cell, determine the active period of unrestricted uplink transmission and the inactive period of restricted uplink transmission on the first cell; and Based on the fact that the first cell is in the activity period, physical downlink control channel (PDCCH) monitoring is performed on the second cell that uses the first cell for PUCCH transmission.

9. A processing apparatus in a wireless communication system, the processing apparatus comprising: At least one processor; as well as At least one computer memory, operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform an operation. The operation includes: Receive cell discontinuous reception DRX configuration for the first cell configured with Physical Uplink Control Channel (PUCCH) resources; Based on the cell DRX configuration for the first cell, determine the active period of unrestricted uplink transmission and the inactive period of restricted uplink transmission on the first cell; and Based on the fact that the first cell is in the activity period, physical downlink control channel (PDCCH) monitoring is performed on the second cell that uses the first cell for PUCCH transmission.

10. A computer-readable storage medium storing at least one program code including instructions that, when executed, cause at least one processor to perform an operation. in, The operation includes: Receive cell discontinuous reception DRX configuration for the first cell configured with Physical Uplink Control Channel (PUCCH) resources; Based on the cell DRX configuration for the first cell, determine the active period of unrestricted uplink transmission and the inactive period of restricted uplink transmission on the first cell; and Based on the fact that the first cell is in the activity period, physical downlink control channel (PDCCH) monitoring is performed on the second cell that uses the first cell for PUCCH transmission.

11. A method for transmitting downlink signals from a base station (BS) to a user equipment (UE) in a wireless communication system, the method comprising the following steps: Send cell discontinuous reception DRX configuration for the first cell configured with physical uplink control channel (PUCCH) resources; Based on the cell DRX configuration for the first cell, determine the active period of unrestricted uplink reception and the inactive period of restricted uplink reception on the first cell; as well as Based on the fact that the first cell is in the activity period, physical downlink control channel (PDCCH) transmission is performed for the second cell that uses the first cell for PUCCH reception.

12. A base station (BS) for transmitting downlink signals to a user equipment (UE) in a wireless communication system, the BS comprising: At least one transceiver; At least one processor; as well as At least one computer memory, operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform an operation. The operation includes: Send cell discontinuous reception DRX configuration for the first cell configured with physical uplink control channel (PUCCH) resources; Based on the cell DRX configuration for the first cell, determine the active period of unrestricted uplink reception and the inactive period of restricted uplink reception on the first cell; and Based on the fact that the first cell is in the activity period, physical downlink control channel (PDCCH) transmission is performed for the second cell that uses the first cell for PUCCH reception.

13. The BS according to claim 12, wherein, The operation includes: based on the first cell being in the activity period, performing Physical Downlink Shared Channel (PDSCH) transmission scheduled on the second cell.

14. The BS according to claim 12, wherein, The operation includes: not performing the PDCCH transmission for the second cell based on the fact that the first cell is in the inactive period.

15. The BS according to claim 12, wherein, The operation includes: not performing PDSCH transmission scheduled on the second cell based on the fact that the first cell is in the inactive period.

16. The BS according to claim 14, wherein, During the inactive period of the first cell, the PDCCH transmission for the second cell is not performed, regardless of whether there is a cell DRX configuration for the second cell.

17. The BS according to claim 12, wherein, The operation includes: delaying the reception of the first PUCCH scheduled for the inactive period of the first cell until after the inactive period.

18. The BS according to claim 17, wherein, The operation of delaying the first PUCCH reception until after the inactive period includes: receiving HARQ-ACK information from the HARQ-ACK codebook within the first PUCCH reception, which is attached to another HARQ-ACK codebook scheduled for after the inactive period of the first cell.

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