Patent Description:
In order to meet the increasing demand with respect to wireless data traffic after the commercialization of <NUM>th generation (<NUM>) communication systems, efforts have been made to develop improved <NUM>th generation (<NUM>) communication systems or pre-<NUM> communication systems. For this reason, <NUM> communication systems or pre-<NUM> communication systems are called beyond <NUM> network communication systems or post-long term evolution (LTE) systems.

In order to achieve high data rates, the implementation of <NUM> communication systems in an ultra-high frequency millimeter-wave (mmWave) band (e.g., a <NUM>-gigahertz (GHz) band) is being considered. In order to reduce path loss of radio waves and increase a transmission distance of radio waves in the ultra-high frequency band for <NUM> communication systems, various technologies such as beamforming, massive multiple-input and multiple output (massive MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large scale antennas are being studied.

Also, in order to improve system networks for <NUM> communication systems, various technologies such as evolved small cells, advanced small cells, cloud radio access networks (cloud-RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving networks, cooperative communication, coordinated multi-points (CoMP), and received-interference cancellation have been developed. In addition, for <NUM> communication systems, advanced coding modulation (ACM) technologies such as hybrid frequency-shift keying (FSK) and quadrature amplitude modulation (QAM) (FQAM) and sliding window superposition coding (SWSC), and advanced access technologies such as filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA), have been developed.

The Internet has evolved from a human-based connection network, where humans create and consume information, to the Internet of things (IoT), where distributed elements such as objects exchange information with each other to process the information. Internet of Everything (IoE) technology, which is a combination of loT technology and big data processing technology through connection with a cloud server, is also emerging. In order to implement the loT, technology elements such as sensing technology, wired/wireless communication and network infrastructures, service interface technology, and security technology are required, and thus, technologies for inter-object connection, such as sensor network, machine to machine (M2M) communication, or machine-type communication (MTC), have recently been studied. In an IoT environment, intelligent Internet technology (IT) services that collect and analyze data generated by connected objects and create new value in human life may be provided. The loT may be applied to fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart home appliances, and advanced medical services through convergence and integration of existing information technology (IT) and various industries.

Accordingly, various attempts have been made to apply <NUM> communication systems to IoT networks. For example, <NUM> communication technologies such as sensor network, M2M communication, and MTC are implemented by using techniques such as beamforming, MIMO, and array antenna. The application of a cloud-RAN as big data processing technology may also be considered as an example of convergence of <NUM> technology and loT technology.

As various services may be provided with the development of wireless communication systems as described above, there is a demand for a method of seamlessly providing the various services.

<NPL>) discloses to provide discussion and decision for NR DCI and UCI design for resource allocation mode <NUM>.

"<NPL>) discloses text about NR and NG-RAN description.

An objective of the disclosure is to provide operating methods and apparatuses therefor of a user equipment (UE) and a base station to perform uplink transmission power control by using a transmission power control parameter transmitted through a downlink control channel.

According to the disclosure, there may be provided operating methods and apparatuses therefor of a user equipment (UE) and a base station to perform uplink transmission power control by using a transmission power control parameter transmitted through a downlink control channel.

Hereinafter, operational principles of the disclosure will be described in detail with reference to the accompanying drawings. While describing the disclosure, detailed descriptions of related well-known functions or configurations that may blur the points of the disclosure are omitted. The terms used herein are those defined in consideration of functions in the disclosure, but the terms may vary according to the intention of users or operators, precedents, etc. Hence, the terms used herein should be defined based on the meaning of the terms together with the descriptions throughout the specification.

It will be understood that each block of flowchart illustrations and combinations of blocks in the flowchart illustrations may be implemented by computer program instructions. Because these computer program instructions may be loaded into a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus, the instructions, which are executed via the processor of the computer or other programmable data processing apparatus, generate means for implementing functions specified in the flowchart block(s). Because these computer program instructions may also be stored in a computer-executable or computer-readable memory that may direct the computer or other programmable data processing equipment to function in a particular manner, the instructions stored in the computer-executable or computer-readable memory may produce an article of manufacture including instruction means for performing the functions stored in the flowchart block(s). Because the computer program instructions may also be loaded into a computer or other programmable data processing equipment, a series of operational steps may be performed on the computer or other programmable data processing equipment to produce a computer implemented process, and thus, the instructions executed on the computer or other programmable data processing equipment may provide steps for implementing the functions specified in the flowchart block(s).

Also, each block may represent a module, segment, or portion of code, which includes one or more executable instructions for implementing specified logical function(s). For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, according to the functionality involved.

The term ". unit" used in the present embodiment refers to a software or hardware component, such as a field-programmable gate array (FPGA) or an application-specific integrated circuit (ASIC), which performs certain tasks. However, the term ". unit" does not mean to be limited to software or hardware. unit" may be configured to be in an addressable storage medium or may be configured to operate one or more processors. unit" may include, by way of example, components, such as software components, object-oriented software components, class components, and task components, processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functionality provided in components and ". units" may be combined into fewer components and ". units" or may be further separated into additional components and ". Furthermore, components and ". units" may be implemented to operate one or more central processing units (CPUs) in a device or a secure multimedia card. unit" in an embodiment of the disclosure may include one or more processors.

In the disclosure, a downlink (DL) denotes a wireless transmission path of a signal transmitted by a base station (BS) to a user equipment (UE), and an uplink (UL) denotes a wireless transmission path of a signal transmitted by a UE to a BS. Hereinafter, although a long term evolution (LTE) or LTE-advanced (LTE-A) system is described as an example, an embodiment of the disclosure may be applied to other communication systems having a similar technical background or channel structure. For example, other communication systems to which an embodiment of the disclosure may be applied may include <NUM> mobile communication technology (<NUM>th generation (<NUM>), new radio (NR), etc.) developed after LTE-A, and <NUM> below may be a concept including existing LTE, LTE-A, and other similar services. Also, the disclosure may be applied to other communication systems through some modifications without departing from the scope of the disclosure at the discretion of one of ordinary skill in the art.

Hereinafter, terms for identifying access nodes, terms indicating network entities, terms indicating messages, terms indicating interfaces between network entities, and terms indicating various identification information used herein are exemplified for convenience of explanation. Accordingly, the disclosure is not limited to terms described below, and other terms denoting objects having the same technical meanings may be used.

Hereinafter, some terms and names defined in the <NUM>rd generation partnership project long term evolution (3GPP LTE) standards may be used for convenience of explanation. However, the disclosure is not limited to the terms and names, and may be equally applied to systems that conform to other standards.

In the following descriptions of the disclosure, well-known functions or configurations are not described in detail when it is deemed that they may unnecessarily obscure the present invention. Hereinafter, an embodiment of the disclosure will be described with reference to the accompanying drawings.

According to an embodiment of the disclosure, a carrier aggregation (CA) technology capable of increasing a data rate by grouping at least two frequency bands is well known. A UE in a system that supports CA may transmit or receive DL/UL data and control information via two or more carrier frequencies configuring a DL or a UL. A plurality of pieces of information may be included in a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), or a sounding reference signal (SRS) and transmitted via the UL.

According to an embodiment of the disclosure, when the UE performs transmission via the UL (transmission via the PUSCH, the PUCCH, or the SRS), the UE may perform transmission power control to decrease interference to an adjacent cell and to increase reception reliability of information to be transmitted via the UL. For UL transmission power control, the UE may configure a transmission power value by using parameters received from a BS and a DL path attenuation value measured by the UE. In this case, some parameters from among the parameters received from the BS may be received by the UE via radio resource control (RRC) signaling, and some parameters may be received by the UE via downlink control information (DCI) of a DL control channel. Also, a transmission power control parameter received by the UE via the DCI of the DL control channel may be transmitted from the BS by using UE-specific DCI transmitted only to a specific UE or may be transmitted from the BS by using group-common DCI transmitted only to UEs of a specific group.

According to an embodiment of the disclosure, in a CA environment, the UE may receive one or more DCls from one or more cells. For example, in a CA environment of three cells, the UE may receive three DCIs from three cells. In this case, the three DCls may be configured as one of UE-specific DCI and group-common DCI (e.g., the three DCls may be configured as three UE-specific DCIs or three group-common DCIs),or may be configured as a combination of UE-specific DCI and group-common DCIs (e.g., the three DCls may be configured as a combination of one UE-specific DCI and two group-common DCIs).

According to an embodiment of the disclosure, a UL transmission power control method using a parameter received via DCI may include an accumulation method and a method of using an absolute value. The accumulation method may be a method of accumulating and using a transmission power control parameter value received by a UE via DCI. The method of using an absolute value may be a method by which the UE uses the transmission power control parameter value received via DCI, without accumulation. The BS according to an embodiment of the disclosure may configure, via RRC signaling, which method from among the two transmission power control methods is to be used.

According to an embodiment of the disclosure, when the accumulation method is to be used, the UE may determine which DCI from among two or more DCls received by the UE is to be used in performing accumulation.

<FIG> is a diagram illustrating a CA system, according to an embodiment of the disclosure.

<FIG> illustrates an example where the number of UL carrier frequencies is equal to the number of DL carrier frequencies, but the disclosure is not limited thereto. That is, the number of UL carrier frequencies may be a subset of the number of DL carrier frequencies. For example, when it is assumed that the number of DL carrier frequencies is N and the number of UL carrier frequencies is M, N ≥ M. In this case, a carrier used in CA may be referred to as a cell.

According to an embodiment of the disclosure, a UE may transmit/receive data and control information via a DL/UL from some cells (i.e., e.g., from two cells) of a BS including N cells. In this case, Cell-<NUM> and Cell-<NUM> may transmit, to the UE, DL control information for DL data transmission. Also, Cell-<NUM> and Cell-<NUM> may transmit, to the UE, UL control information for UL data transmission.

Transmission power control with respect to a PUCCH in a legacy wireless communication system is as in [Equation <NUM>].

In [Equation <NUM>], δPUCCH(i) indicates transmission power of a PUCCH in an ith subframe of the UE, and each of parameters in [Equation <NUM>] is as below.

- PO_PUCCH: A parameter that includes PO_NOMINAL_PUCCH + PO_UE_PUCCH, and is a value configured for the UE by the BS via RRC signaling. In particular, PO_NOMINAL_PUCCH is a cell-specific value including <NUM>-bit information and having a range of [-<NUM>, <NUM>] dB. Also, PO_UE_PUCCH is a UE-specific value including <NUM>-bit information and having a range of [-<NUM>, <NUM>] dB. The cell-specific value is transmitted from the BS to the UE via a system information block (SIB), and the UE-specific value is transmitted from the BS to the UE via dedicated RRC signaling. - PLc: A path loss value calculated by the UE. The UE calculates the path loss value from reception power of a cell-specific reference signal (CRS) of a DL channel transmitted by the BS. In more detail, the BS transmits referenceSignalPower and a filtering coefficient to the UE via UE-specific or cell-specific RRC signaling, and based on this, the UE calculates the path loss value as below. PLc=referenceSignalPower - higher layer filtered RSRP
- ΔF_PUCCH(): A value that is transmitted to the UE via higher layer signaling (cell-specific signaling or UE-specific RRC signaling), that varies according to a format of a PUCCH, and that has a relative value with respect to PUCCH Format 1a (<NUM>-bit HARQ-ACK/NACK transmission). The value of ΔF_PUCCH(F) is configured as in [Table <NUM>].

- ΔTxD(F') is a value that is transmitted to the UE via higher layer signaling (cell-specific signaling or UE-specific RRC signaling) when a PUCCH is transmitted via <NUM>-antanna ports (i.e., a space frequency block code (SFBC)), and that varies according to a format of the PUCCH. When the SFBC is not used, ΔTxD(F') = <NUM>. The value of ΔTxD(F') is configured as in [Table <NUM>].

- h(nCQI,nHARQ,nSR): Different values may be used according to a format of a PUCCH. In this case, nCQI may indicate the number of bits used in feedback of channel quality information (CQI). nHARQ may indicate the number of bits used in hybrid automatic repeat request (HARQ)-ACK/NACK feedback. Also, nSR is <NUM> or <NUM> that is a bit used in feedback of a scheduling request. h(ncQI,nHARQ,nSR) may have different values according to a format of the PUCCH. - g(i) is a parameter for performing closed-loop power control. The BS may correct PUCCH transmission power to be UE-specific. Unlike PUSCH transmission power control, in PUCCH transmission power control, only accumulation-based transmission power control is performed, and g(i) is given as in [Equation <NUM>].

That is, g(i) in an ith subframe may be calculated by accumulating a value of δPUCCH, which has been transmitted in DCI to the UE via a physical downlink control channel (PDCCH) in an i-kmth subframe, to a value of g(i-<NUM>) used in a previous subframe (i.e., i - 1st subframe). The value of δPUCCH may vary according to a DCI format. For DCI formats 1A/1B/1D/<NUM>/2A/2B/2C/<NUM>/<NUM>, same values as accumulated δPUSCH of [Table <NUM>] may be used. In the case of DCI format 3A, the value of δPUCCH may be equal to a value of δPUSCH used in [Table <NUM>].

In [Equation <NUM>], a value of M and a value of k<NUM> may be differently used in a frequency division duplex (FDD) system and a time division duplex (TDD) system. In more detail, in the FDD system, M=<NUM> and K<NUM>=<NUM>, and in the TDD system, M and k<NUM> may have different values as in [Table <NUM>] according to DL/UL configuration.

<FIG> is a diagram for describing an example of transmission of DL data and DL control information and transmission of UL control information in a CA system, according to an embodiment of the disclosure.

According to an embodiment of the disclosure, component carrier#<NUM> (CC#<NUM>) may be referred to as a primary cell (PCell).

CC#<NUM> to CC#N may be referred to as secondary cells (SCells). In this case, CC#<NUM> may transmit, to a UE, DL data and control information that are respectively PDCCH-<NUM> and PDSCH-<NUM>.

CC#<NUM> may also transmit, to the UE, DL data and control information that are respectively PDCCH-<NUM> and PDSCH-<NUM>.

PDCCH-<NUM> transmitted from PCell (CC#<NUM>) to the UE may include resource allocation information of PDSCH-<NUM> transmitted from PCell to the UE, and a <NUM>-bit δPUCCH value of [Table <NUM>] which is a transmission power control parameter value of a PUCCH transmitted on PCell. PDCCH-<NUM> transmitted from SCell (CC#<NUM>) to the UE may include resource allocation information of PDSCH-<NUM> transmitted from CC#<NUM> to the UE, and resource allocation information of a PUCCH transmitted on PCell. In this case, the resource allocation information of the PUCCH may reuse a transmission power control (TPC) command field.

That is, PUCCHs transmitted from Scell do not have a particular field for separate PUCCH resource allocation information. In this case, the UE may reinterpret, as PUCCH resource allocation information, a <NUM>-bit TPC command field indicating a δPUCCH value by the BS.

Although not shown in <FIG>, an embodiment of the disclosure may be applied even when three cells transmit a PDCCH. Accordingly, embodiments of the disclosure may be applied, regardless of the number of cells. When CC#<NUM> and CC#<NUM> respectively transmit PDCCH-<NUM> and PDSCH-<NUM>, and PDCCH-<NUM> and PDSCH-<NUM>, TPC command fields of PDCCH-<NUM> and PDCCH-<NUM> may include resource allocation information of a PUCCH transmitted on PCell. The TPC command fields of PDCCH-<NUM> and PDCCH-<NUM> may have the same value, and the UE may reinterpret all of the TPC command fields of PDCCH-<NUM> and PDCCH-<NUM> as the resource allocation information of the PUCCH transmitted via PCell.

<FIG> is a diagram for describing a timing at which a UE applies a UL transmission power control parameter obtained via DCI, according to an embodiment of the disclosure.

In an FDD system, HARQ ACK/NACK information about a physical downlink shared channel (PDSCH) received in an n-<NUM>th subframe via a DL is transmitted via a PUCCH of an nth subframe. Accordingly, a value of δPUCCH a UE obtains from a TPC command field of UE-specific DCI (or a value of δPUCCH the UE obtains from group-common DCI) received in the n-<NUM>th subframe is used in transmission of the PUCCH of the nth subframe.

In a TDD system, rules as in [Table <NUM>] may be applied. In more detail, in a system following TDD DL/UL configuration #<NUM>, configuration of a DL and a UL may be as in an example of <FIG>. In this case, D may indicate a DL subframe (DL), U indicates a UL subframe (UL), and S may indicate s special subframe where a DL, a UL, and a gap coexist.

Referring to [Table <NUM>], a value of δPUCCH (the value of δPUCCH the UE obtains from the TPC command field of UE-specific DCI or the value of δPUCCH the UE obtains from group-common DCI) to be applied to subframe-<NUM> corresponds to a value of δPUCCH transmitted in a previous sixth subframe before subframe-<NUM>. That is, the value of δPUCCH to be applied to subframe-<NUM> may correspond to the value of δPUCCH transmitted in subframe no.

A value of δPUCCH to be applied to subframe-<NUM> may correspond to a value of δPUCCH transmitted in a previous fourth subframe before subframe-<NUM>. That is, the value of δPUCCH to be applied to subframe-<NUM> may correspond to the value of δPUCCH transmitted in subframe no.

A value of δPUCCH to be applied to subframe-<NUM> may correspond to a value of δPUCCH transmitted in a previous sixth subframe before subframe-<NUM>. That is, the value of δPUCCH to be applied to subframe-<NUM> may correspond to the value of δPUCCH transmitted in subframe no.

Lastly, a value of δPUCCH to be applied to subframe-<NUM> may correspond to a value of δPUCCH transmitted in a previous fourth subframe before subframe-<NUM>. That is, the value of δPUCCH to be applied to subframe-<NUM> may correspond to the value of δPUCCH transmitted in subframe no.

<FIG> is a diagram for describing an example where a UL transmission power control parameter a UE obtains via DCI is applied, according to an embodiment of the disclosure.

A UE may receive one or more UE-specific DCls or group-common DCIs from one or more cells. In this case, UE-specific DCI indicates a DCI format with a cyclic redundancy check (CRC) of DCI scrambled by cell radio network temporary identifier (C-RNTI) or semi-persistent scheduling (SPS)-RNTI, and more particularly, may indicate DCI format <NUM>, 1A, <NUM>, 2A, 2B, or 2C or DCI format 0_0, 0_1, 1_0, or 1_1.

Group-common DCI indicates a DCI format with a CRC of DCI scrambled by TPC-PUCCH-RNTI (or TPC-PUSCH-RNTI or TPC-SRS-RNTI), and more particularly, may indicate DCI format <NUM> or 3A or DCI format 2_2 or 2_3.

The UE may receive, in a particular subframe (e.g., an nth subframe), one or more DCls, e.g., two or more UE-specific DCIs, two or more group-common DCIs, or two or more UE-specific DCls and group-common DCIs, from one or more cells. Upon reception of the DCls, the UE may determine whether there is DCI received from PCell, and when there is the DCI received from the PCell, the UE may obtain a value of δPUCCH from the DCI. That is, the UE may obtain the value of δPUCCH from a TPC command field of UE-specific DCI or group-common DCI.

The UE may obtain resource information of a PUCCH to be transmitted on the PCell, from a TPC command field of UE-specific DCI received from SCell.

When the UE receives two or more UE-specific DCIs from two or more SCells, the UE may not expect different UE-specific DCls to indicate two or more pieces of different PUCCH resource information. That is, a BS may transmit the same PUCCH resource information via different UE-specific DCIs.

After the UE respectively obtains the value of δPUCCH and the resource information of the PUCCH for PUCCH transmission from DCIs of the PCell and the SCell, the UE may configure a transmission power value of the PUCCH to be transmitted on the PCell. In more detail, the UE may update a value of g(i) by using [Equation <NUM>], and may configure a value of PPUCCH(i) by using [Equation <NUM>]. The UE may transmit the PUCCH in an ith subframe by using the configured PPUCCH(i).

<FIG> is a diagram for describing another example of transmission of DL data and DL control information and transmission of UL control information in a CA system, according to an embodiment of the disclosure.

Unlike <FIG>, in <FIG>, CC#<NUM> may not transmit DL data and control information to a UE, and CC#<NUM> and CC#N may respectively transmit PDCCH-<NUM> and PDSCH-<NUM>, and PDCCH-N and PDSCH-N to the UE.

According to descriptions of <FIG>, the UE may obtain information about a value of δPUCCH via a <NUM>-bit TPC command field of PDCCH-<NUM> transmitted from PCell (CC#<NUM>), and may obtain resource allocation information of a PUCCH to be transmitted on the PCell, via a <NUM>-bit TPC command field of PDCCHs transmitted from SCells. In this case, when two or more SCells transmit PDCCHs, <NUM>-bit TPC command fields of the PDCCHs of the respective SCells may have the same value.

Referring to <FIG>, because there are not PDCCH-<NUM> and PDSCH-<NUM> transmitted from the PCell, the UE may not be able to obtain, from DCI of PDCCH-<NUM>, a value of δPUCCH the UE may reference to transmit the PUCCH.

<FIG> is a diagram for describing an example of operations of a UE according to <FIG>, according to an embodiment of the disclosure.

A UE according to an embodiment of the disclosure may receive, in a (n-k)th subframe, one or more DCls from one or more cells.

Then, the UE may transmit a PUCCH on PCell, in an nth subframe. In this case, a value of k is fixed to <NUM> in the case of an FDD system, and in the case of the TDD system, a value of k follows [Table <NUM>] according to configuration of a DL and a UL (i.e., according to TDD DL/UL configuration).

In <FIG>, the UE may determine whether UE-specific DCI received in the (n-k)th subframe from the PCell exists.

When the UE-specific DCI received from the PCell exists, the UE may obtain a value of δPUCCH from the UE-specific DCI.

When the UE-specific DCI received from the PCell does not exist, the UE may determine whether group-common DCI received from the PCell exists.

When group-common DCI received from the PCell exists in the (n-k)th subframe, the UE may obtain the value of δPUCCH from the group-common DCI.

When the group-common DCI received from the PCell does not exist in the (n-k)th subframe, the UE may configure the value of δPUCCH as <NUM> dB. The UE may obtain resource information of a PUCCH to be transmitted on the PCell, from a TPC command field of UE-specific DCI received from SCell.

After the UE respectively obtains the value of δPUCCH and the resource information of the PUCCH for PUCCH transmission from DCIs of the PCell and the SCell, the UE may configure a transmission power value of the PUCCH to be transmitted on the PCell. In more detail, the UE may update a value of g(i) (where i = n) by using [Equation <NUM>], and may configure a value of PPUCCH(n) by using [Equation <NUM>]. The UE may transmit the PUCCH in the nth subframe by using the configured PPUCCH(n).

As described with reference to <FIG>, according to whether a <NUM>-bit TPC command field is transmitted from DCI of PCell or DCI of SCell, UE interpretation of a TPC command field may vary. That is, the UE may obtain a value of δPUCCH from a TPC command field of the DCI transmitted from the PCell, and may obtain resource information of a PUCCH from a TPC command field of DCIs transmitted from SCells. Because such an operation does not require an additional bit for indicating resource allocation information of the PUCCH, an overhead of the number of DCI bits may be reduced.

In a communication system according to an embodiment of the disclosure, the number of DCI bits may need to increase. Accordingly, in a communication system according to an embodiment of the disclosure, a DCI bit for indicating, to the UE, a value of δPUCCH for transmission power control of the PUCCH, and a DCI bit for indicating, to the UE, the resource allocation information of the PUCCH may separately exist. In this situation, the UE may receive two or more DCls from two or more cells, and it is required to define operations the UE should perform at that time. For example, it is required to define whether the UE conforms to a TPC command field of UE-specific DCI of the PCell or conforms to all of two or more TPC command fields transmitted from the PCell and SCell.

<FIG> is a diagram for describing transmission of DL data and DL control information and transmission of UL control information in a system to which CA is applied, according to an embodiment of the disclosure.

A UE may receive, in a (n-k)th subframe, one or more DCls from one or more cells. Then, the UE may transmit a PUCCH on PCell, in an nth subframe.

In a communication system according to an embodiment of the disclosure, in order to support a service having various latencies, a BS may flexibly configure a value of k. In this case, k may indicate a time difference between a time when DCI is received and a time when a PUCCH is transmitted.

In more detail, a value of k in an FDD system may be <NUM>, and a value of k in a TDD system may correspond to values defined in [Table <NUM>], according to configuration of a DL and a UL. That is, a fixed value of k may be used.

According to an embodiment of the disclosure, a ratio and a pattern of a DL and a UL configuring a frame or a slot may vary and may be dynamically changed. Accordingly, the BS may configure or indicate a value of k for the UE.

For example, the BS may indicate, via RRC signaling, the UE of k value candidates including two or more values of k, and may indicate, for the UE, one value of k from the k value candidates via DCI. In this case, the BS may configure a value of k, by sufficiently considering a processing time capability of the UE. In more detail, the BS may obtain information about a processing time capability of each UE, in a procedure of negotiating a capability with each UE. For example, UE-A may provide a fast processing time, and thus, may use a small value of k, but UE-B may not provide a fast processing time, and thus, may should use a large value of k.

According to an embodiment of the disclosure, the UE may determine, by using the value of k, whether UE-specific DCI received in the (n-k)th subframe from the PCell exists.

When the UE-specific DCI received from the PCell exists, the UE may obtain a value of δPUCCH from a TPC command field of the DCI.

When the UE-specific DCI received from the PCell does not exist, the UE may determine whether UE-specific DCI received from SCell exists.

When the UE-specific DCI received from the SCell exists, the UE may obtain a value of δPUCCH from a TPC command field of the DCI.

When the UE receives two or more UE-specific DCIs from two or more SCells, the UE may obtain a value of δPUCCH from a TPC command field of UE-specific DCI received from SCell having a lowest cell index.

When there are not UE-specific DCIs received from PCell and SCell, the UE may configure the value of δPUCCH as <NUM> dB.

The UE may update a value of g(i) (where i = n) by using [Equation <NUM>], based on the value δPUCCH obtained through UE-specific DCI of PCell or SCell (when UE-specific DCI received from PCell or SCell exists), or the value of δPUCCH configured as <NUM> dB (when UE-specific DCI received from the PCell or the SCell does not exist).

The BS may transmit resource information of the PUCCH via the UE-specific DCI of the PCell and the one or more SCells. In this case, the BS may configure the resource information of the PUCCH, which is transmitted via UE-specific DCI, to be the same in all cells and may transmit the source information of the PUCCH to the UE.

Accordingly, the UE may obtain the resource information of the PUCCH via UE-specific DCI transmitted from one cell from among the PCell or the SCells. The UE may configure a transmission power value of the PUCCH to be transmitted on PCell, by using the updated value of g(i) and the obtained resource information of the PUCCH. Then, the UE may transmit the PUCCH in the nth subframe, by using the configured transmission power value of the PUCCH.

A UE according to an embodiment of the disclosure may receive, in a (n-k)th subframe, one or more DCIs from one or more cells. Then, the UE may transmit a PUCCH on PCell, in an nth subframe.

As described with reference to <FIG>, the UE may determine, by using a value of k, whether UE-specific DCI received in the (n-k)th subframe from the PCell exists.

When the UE receives two or more UE-specific DCIs from two or more SCells, the UE may obtain a value of δPUCCH from a TPC command field of UE-specific DCI received from SCell, according to a predefined rule between a BS and the UE. For example, the UE may obtain a value of δPUCCH from a TPC command field of UE-specific DCI received from SCell having a lowest cell index.

According to an embodiment of the disclosure, when there are not UE-specific DCls received from PCell and SCell, the UE may determine whether there is group-common DCI received from the PCell.

When the group-common DCI received from the PCell exists, the UE may obtain a value of δPUCCH from the group-common DCI.

When UE-specific DCI received from the PCell or SCell does not exist and the group-common DCI received from the PCell does not exist, the UE may configure the value of δPUCCH as <NUM> dB.

The UE may update the value of g(i) (where i = n) by using [Equation <NUM>], based on the obtained δPUCCH (when UE-specific DCI received from PCell or SCell exists or when group-common DCI received from the PCell exists and UE-specific DCI received from the SCell does not exist), or the value of δPUCCH configured as <NUM> dB (when UE-specific DCI or group-common DCI received from the PCell does not exist and UE-specific DCI received from the SCell does not exist).

Like in <FIG>, the BS may transmit resource information of the PUCCH via the UE-specific DCI of the PCell and the one or more SCells, and in this case, the BS may configure the resource information of the PUCCH, which is transmitted via the UE-specific DCI, to be the same in all cells and may transmit the resource information of the PUCCH to the UE.

According to an embodiment of the disclosure, in <FIG>, when UE-specific DCI received from PCell does not exist, a UE may determine whether UE-specific DCI from SCell having a lowest cell index exists, and when the DCI does not exist, may determine whether group-common DCI transmitted from the PCell exists.

According to an embodiment of the disclosure, in <FIG>, when UE-specific DCI received from PCell does not exist, a UE may first determine whether group-common DCI transmitted from the PCell exists, and when the corresponding DCI exists, the UE may obtain a value of δPUCCH from the group-common DCI.

When UE-specific DCI nor group-common DCI transmitted from the PCell does not exist, the UE may determine whether UE-specific DCI received from SCell exists. When UE-specific DCI is transmitted from two or more SCells, the UE may obtain a value of δPUCCH via the UE-specific DCI transmitted from SCell having a lowest cell index.

When UE-specific DCI or group-common DCI received from the PCell does not exist, and UE-specific DCIs received from SCells do not exist, the UE may configure the value of δPUCCH as <NUM> dB. The UE may update a value of g(i) (where i = n), by using [Equation <NUM>], based on the obtained value of δPUCCH or the value of δPUCCH configured as <NUM> dB.

Like in <FIG> and <FIG>, a BS may transmit resource information of a PUCCH via UE-specific DCI of the PCell or the one or more SCells. In this case, the BS may configure the resource information of the PUCCH, which is transmitted via the UE-specific DCI, to be the same in all cells and may transmit the resource information of the PUCCH to the UE.

Accordingly, the UE may obtain the resource information of the PUCCH via UE-specific DCI transmitted from one cell from among the PCell or the SCells. The UE may configure a transmission power value of the PUCCH to be transmitted on PCell, by using the updated value of g(i) and the obtained resource information of the PUCCH. Then, the UE may transmit the PUCCH in an nth subframe, by using the configured transmission power value of the PUCCH.

As another example of PUCCH resource information transmission by the BS, the BS may transmit PUCCH resource information to the UE, according to a predefined rule between the BS and the UE. That is, the BS may not equally configure and transmit PUCCH resource information via UE-specific DCI transmitted from one cell from among the PCell or the SCells. According to an embodiment of the disclosure, the UE and the BS may predefine to transmit PUCCH resource information via UE-specific DCI transmitted from the PCell.

In this case, the UE may obtain the PUCCH resource information via the UE-specific DCI transmitted from the PCell, and may ignore PUCCH resource information included in UE-specific DCI transmitted from SCell or SCells, regardless of configuration by the BS. As another example, the BS may configure a field of PUCCH resource information with a particular value, the PUCCH resource information being included in UE-specific DCI transmitted from SCell or SCells. For example, the BS may configure all bits of the field as '<NUM>' or '<NUM>'. Upon reception of this, the UE may ignore the field about the PUCCH resource information. For convenience of explanation, although an example is provided in which the field about the PUCCH resource information included in the UE-specific DCI transmitted from SCell or SCells is configured with the particular value, in general, the BS may transmit PUCCH resource information valid only for UE-specific DCI transmitted from a particular cell predefined with the UE, and may transmit PUCCH resource information invalid for UE-specific DCI transmitted from other cells. In this case, the invalid PUCCH resource information may be regarded as a field about PUCCH resource information configured with a particular value.

As another example of PUCCH resource information transmission by the BS, the BS may inform the UE of PUCCH resource information via UE-specific DCls transmitted from PCell and SCell having a lowest cell index. The UE not having received the UE-specific DCI from the PCell may obtain the PUCCH resource information via reception of the UE-specific DCI transmitted from the SCell having a lowest cell index.

The UE may obtain the PUCCH resource information from the UE-specific DCls transmitted from the PCell and the SCell having a lowest cell index, and may ignore PUCCH resource information included in UE-specific DCI transmitted from SCell or SCells, regardless of configuration by the BS. Alternatively, the BS may configure a field of PUCCH resource information with a particular value, the PUCCH resource information being included in UE-specific DCI transmitted from SCell or SCells. For example, the BS may configure all bits of the field as '<NUM>' or '<NUM>'.

As another example, the BS may inform the UE of PUCCH resource information via UE-specific DCI transmitted on particular SCell. For example, the BS may inform the UE of PUCCH resource information via UE-specific DCI transmitted on SCell having a lowest cell index. The UE may ignore PUCCH resource information included in UE-specific DCI transmitted from the PCell and UE-specific DCI transmitted from SCell or SCells, regardless of configuration by the BS.

Alternatively, the BS may configure a field of PUCCH resource information with a particular value, the PUCCH resource information being included in UE-specific DCIs excluding UE-specific DCI to be referenced by the UE to obtain PUCCH resource information. For example, the BS may configure all bits of the field as '<NUM>' or '<NUM>'.

As another example, the BS may inform the UE of PUCCH resource information via UE-specific DCI transmitted on particular SCell. For example, the BS may inform the UE of PUCCH resource information via UE-specific DCI transmitted on SCell having a lowest cell index. The UE may ignore PUCCH resource information included in UE-specific DCI received from the PCell and UE-specific DCI transmitted from SCell or SCells, regardless of configuration by the BS.

As another example, the BS may inform the UE of a cell index to be referenced by the UE to obtain PUCCH resource information, via RRC signaling or a medium access control control element (MAC CE).

When obtaining the index, the UE may obtain PUCCH resource information from UE-specific DCI transmitted from a cell having the cell index. The UE may ignore PUCCH resource information transmitted from UE-specific DCls transmitted from a cell or cells not having the index informed by the BS.

A UE according to an embodiment of the disclosure may update a value of g(i) of [Equation <NUM>] by using values of δPUCCH obtained from all UE-specific DCIs received from PCell and one or more SCells. That is, the UE may accumulate and use all values of δPUCCH included in the UE-specific DCIs. In this case, values of δPUCCH included in group-common DCls may not be accumulated.

When the received UE-specific DCI does not exist, the UE may configure the value of δPUCCH as <NUM> dB and may update the value of g(i) by using [Equation <NUM>].

Also, as described above with reference to <FIG>, the UE may obtain resource information of a PUCCH by using at least one of the above-described methods.

The UE may configure a transmission power value of the PUCCH to be transmitted on PCell, by using the updated value of g(i) and the obtained resource information of the PUCCH.

The UE may transmit the PUCCH in an nth subframe, by using the configured transmission power value of the PUCCH.

<FIG> is a diagram for describing a subframe and a slot, according to an embodiment of the disclosure.

One subframe may have a length of <NUM> on a time axis, and one slot may include <NUM> symbols. When a subcarrier spacing of <NUM> is used, one slot including <NUM> symbols has a length of <NUM>, and thus, one slot and one subframe may be the same.

When a subcarrier spacing of <NUM> is used, one slot including <NUM> symbols has a length of <NUM>, and thus, one subframe may include two slots. Also, when a subcarrier spacing of <NUM> is used, one slot including <NUM> symbols has a length of <NUM>, and thus, one subframe may include four slots. Accordingly, when a subcarrier spacing Δf is N times <NUM>, the number of slots including one subframe may be increased by N times.

Accordingly, such rules may be applied even when subcarrier spacings not shown in <FIG> are used. For example, when a subcarrier spacing of <NUM> is used, Δf is <NUM> times <NUM>, and thus, the number of slots including one subframe may be <NUM>.

<FIG> is a diagram for describing slot-based scheduling, according to an embodiment of the disclosure.

An nth DL slot may include a PDCCH and a PDSCH, and a (n+k1)th UL slot may include a PUSCH and a PUCCH. In this case, for convenience of explanation, the PDCCH of the nth slot includes one symbol, but the PDCCH may include two symbols or three symbols. Also, although a position of a symbol on which the PDCCH is to be transmitted is a first symbol, the disclosure is not limited thereto. That is, a position of a symbol on which the PDCCH is to be transmitted may be a second symbol or after the second symbol.

Also, although the PUCCH is to be transmitted on a last symbol in the (n+k1)th slot, the PUCCH may be transmitted on a random position from among <NUM> symbols constituting the (n+k1)th slot. Also, although the PUCCH includes one symbol, the number of symbols constituting the PUCCH may be equal to or greater than <NUM> and equal to or less than <NUM>.

<FIG> is a diagram for describing mini-slot-based scheduling, according to an embodiment of the disclosure.

A DL mini-slot may include a PDCCH and a PDSCH in an nth DL slot. In this case, although a mini-slot includes one PDCCH symbol and two PDSCH symbols, the disclosure is not limited thereto. That is, a case being smaller than the number of PDSCH symbols used in DL slot-based scheduling may be referred to as the DL mini-slot.

A (n+k2)th UL slot may include a PUSCH and a PUCCH. In this case, for convenience of explanation, a UL mini-slot in the (n+k2)th UL slot includes <NUM> symbols, but the disclosure is limited thereto. That is, a case being smaller than the number of PUSCH symbols used in UL slot-based scheduling may be referred to as the UL mini-slot. Also, although the PUCCH is to be transmitted on a last symbol in the (n+k2)th slot, the PUCCH may be transmitted on a random position from among <NUM> symbols constituting the (n+k2)th UL slot. Also, although the PUCCH includes one symbol, the number of symbols constituting the PUCCH may be equal to or greater than <NUM> and equal to or less than <NUM>.

<FIG> is a diagram for describing a case where slot-based scheduling and mini-slot-based scheduling coexist in a system to which CA is applied, according to an embodiment of the disclosure.

It is assumed that a BS transmits a PDCCH and a PDSCH in an n1th slot via slot-based scheduling on carrier no. <NUM> (CC#<NUM>), and CC#<NUM> is PCell. Also, it is assumed that the BS transmits a PDCCH and a PDSCH in a mini-slot including <NUM> symbols within an n2th slot via mini-slot-based scheduling on carrier no. <NUM> (CC#<NUM>). Also, it is assumed that the BS transmits a PDCCH and a PDSCH in a mini-slot including <NUM> symbols within an n3th slot via mini-slot-based scheduling on carrier no. <NUM> (CC#<NUM>). Lastly, it is assumed that a PUCCH is transmitted only via CC#<NUM> that is the PCell.

In this case, n1, n2, and n3 may be different from each other, but it is possible that n1 + k1 = n2 + k2 = n3 + k3. This may mean that HARQ-ACK/NACK information about a PDSCH which includes a slot or a mini-slot and which is transmitted in a DL of each CC may be transmitted via a PUCCH of the same time.

Also, although the PUCCH is transmitted via all cells in <FIG>, this is merely an example considering a case where a UE that does not support CA accesses a particular cell, in view of a system. That is, UE-<NUM> that accesses CC#<NUM> and does not have a CA support capability may receive the PDCCH and the PDSCH on a DL carrier of CC#<NUM> and may transmit the PUCCH on a UL carrier of CC#<NUM>.

Also, UE-<NUM> that accesses CC#<NUM> and does not have a CA support capability may receive the PDCCH and the PDSCH on a DL carrier of CC#<NUM> and may transmit the PUCCH on a UL carrier of CC#<NUM>. Unlike this, UE-<NUM> having a CA support capability may receive the PDCCH and the PDSCH on DL carriers of CC#<NUM>, CC#<NUM>, and CC#<NUM> and may transmit the PUCCH on a UL carrier of CC#<NUM>. In this case, it is assumed that CC#<NUM> is the PCell. <FIG> illustrates three CCs, but the disclosure may be applied to a CA scenario of at least four CCs.

Under the aforementioned assumption, a UE having a CA support capability may obtain timing information of a PUCCH (i.e., k1 value) which indicates that the PUCCH is to be transmitted in a (n1+k1)th slot, resource information of the PUCCH transmitted in the (n1+k1)th slot, and a value of δPUCCH for configuring a transmission power value of the PUCCH, from a DCI field of a PDCCH transmitted in the n1th slot of CC#<NUM>.

The UE may obtain timing information of a PUCCH (i.e., k2 value) which indicates that the PUCCH is to be transmitted in a (n2+k2)th slot, resource information of the PUCCH transmitted in the (n2+k2)th slot, and a value of δPUCCH for configuring a transmission power value of the PUCCH, from a DCI field of a PDCCH transmitted in a mini-slot within the n2th slot of CC#<NUM>.

Likewise, the UE may obtain timing information of a PUCCH (i.e., k3 value) which indicates that the PUCCH is to be transmitted in a (n3+k3)th slot, resource information of the PUCCH transmitted in the (n3+k3)th slot, and a value of δPUCCH for configuring a transmission power value of the PUCCH, from a DCI field of a PDCCH transmitted in a mini-slot within the n3th slot of CC#<NUM>.

<FIG> is a diagram for describing transmission of DL data and DL control information and transmission of UL control information in a CA environment where slot-based scheduling and mini-slot-based scheduling coexist, according to an embodiment of the disclosure.

A UE according to an embodiment of the disclosure may receive one or more DCls from one or more cells. In this case, DCI may be UE-specific DCI or group-common DCI.

As shown in <FIG>, the UE may receive, on each CC, a PDSCH and a PDCCH including control information about the PDSCH which are transmitted via slot-based or mini-slot-based scheduling in an n1th slot of CC#<NUM>, an n2th slot of CC#<NUM>, and an n3th slot of CC#<NUM>. In this case, the PDCCH received on each CC is a PDCCH about slot-based or mini-slot-based scheduling, and thus, DCI may be regarded as UE-specific DCI. Although not shown in <FIG>, in addition to the UE-specific DCI, the UE may receive group-common DCI on each CC.

Accordingly, the UE may require a method of updating g(i) defined in [Equation <NUM>] for configuring a transmission power value of a PUCCH transmitted at a time of n1 + k1 = n2 + k2 = n3 + k3 shown in <FIG>. That is, when the UE receives two or more UE-specific DCIs or group-common DCls, the UE may need consideration for an accumulation method with respect to values of δPUCCH. In order to support this, a BS and the UE may predetermine a predefined period (or window).

<FIG> and <FIG> are diagrams for describing a start point and an end point of accumulation of a value of δPUCCH, according to an embodiment of the disclosure.

<FIG> illustrates an example where PDCCH-<NUM> is received before PUCCH-<NUM> is transmitted, and <FIG> illustrates an example where PDCCH-<NUM> is received after PUCCH-<NUM> is transmitted.

A UE according to an embodiment of the disclosure may regard a time when reception of UE-specific DCI including information about current PUCCH transmission ends, as a time to start accumulation of a value of δPUCCH, and may obtain values of δPUCCH from all DCIs (one or more UE-specific DCls and group-common DCls transmitted from one or more cells) received within a predefined period starting from a time when the UE-specific DCI is received, and may accumulate all the obtained values of δPUCCH.

PDCCH-<NUM> indicates UE-specific DCI including information about PUCCH-<NUM> to be currently transmitted by the UE, and PDCCH-<NUM> indicates UE-specific DCI including information about PUCCH-<NUM> transmitted immediately before the PUCCH-<NUM> to be currently transmitted. In this case, a BS and the UE may predefine that UE-specific DCI indicating a start of accumulation of a value of δPUCCH (i.e., the UE-specific DCI including the information about transmission of the PUCCH-<NUM> to be currently transmitted) will be transmitted only from PCell.

The BS and the UE may predefine that, when the UE-specific DCI transmitted from the PCell does not exist, UE-specific DCI transmitted from particular SCell indicates a start of accumulation of a value of δPUCCH. In this case, the BS and the UE may predefine that the particular SCell is a cell having a lowest cell index (or a cell having a highest cell index) from among SCells. As another example, the BS may configure the UE with a cell index indicating a start of accumulation of a value of δPUCCH. Upon reception of this, the UE may start accumulation of a value of δPUCCH at a point when reception of UE-specific DCI transmitted from a cell having the cell index ends.

The accumulation of a value of δPUCCH may end before transmission of a PUCCH (PUCCH-<NUM>) to be currently transmitted. That is, the UE may start the accumulation of a value of δPUCCH at a point when reception of the PDCCH-<NUM> ends and then may end the accumulation of a value of δPUCCH at a point when transmission of the PUCCH-<NUM> starts. However, in this case, a time period in which the UE may update a value of g(i) of [Equation <NUM>] by using accumulated values of δPUCCH and may configure transmission power for transmission of the PUCCH may be insufficient. In this case, the accumulation of a value of δPUCCH may end before transmission of the PUCCH (PUCCH-<NUM>) to be currently transmitted starts. This is marked as an offset in <FIG> and <FIG>.

Such offset information should be determined, in consideration of a processing time capability of the UE, and may be a predefined value. Alternatively, the BS may configure the UE with the offset information via RRC signaling. Alternatively, based on a value configured by the BS, the UE may calculate the offset information.

As another example of a start of accumulation of a value of δPUCCH, as shown in <FIG> and <FIG>, accumulation of a value of δPUCCH may start based on a pre-transmitted PUCCH (PUCCH-<NUM>), not in a way accumulation of a value of δPUCCH starts based on UE-specific DCI including information about current transmission of a PUCCH (PUCCH-<NUM>) as described above with reference to <FIG> and <FIG>.

In more detail, a PUCCH to be transmitted in a (n1 + k1)th slot of <FIG> is defined as a 'currently transmitted PUCCH (PUCCH-<NUM> of <FIG>)', and a PUCCH transmitted immediately before the currently transmitted PUCCH is defined as an 'immediately-before transmitted PUCCH (PUCCH-<NUM> of <FIG>)'.

In this case, a start of accumulation of a value of δPUCCH used in configuring a transmission power value of the currently transmitted PUCCH may be determined based on a transmission time of the immediately-before transmitted PUCCH (PUCCH-<NUM>). That is, the UE may start accumulation of a value of δPUCCH, based on a transmission start point of the immediately-before transmitted PUCCH (PUCCH-<NUM>) (or a transmission end point of PUCCH-<NUM>).

For example, when the transmission time of the immediately-before transmitted PUCCH-<NUM> is a pth symbol of a jth slot and the PUCCH-<NUM> includes L symbols, the UE may start the accumulation of a value of δPUCCH on a symbol after the pth symbol of the jth slot (based on the transmission start point of the PUCCH-<NUM>). Alternatively, the UE may start the accumulation of a value of δPUCCH on a symbol after a (p + L)th symbol of the jth slot (based on the transmission end point of the PUCCH-<NUM>).

The end of the accumulation of a value of δPUCCH may be performed up to a start of transmission of the currently transmitted PUCCH (PUCCH-<NUM>) or may be performed up to an offset with respect to the transmission of the currently transmitted PUCCH (PUCCH-<NUM>).

In another example, as shown in <FIG> and <FIG>, the end of the accumulation of a value of δPUCCH may be performed at a point when reception of the PDCCH-<NUM> including information about the currently transmitted PUCCH-<NUM> ends. Although not shown in <FIG> and <FIG>, the accumulation of a value of δPUCCH may end at a point when reception of the PDCCH-<NUM> starts.

In this case, the BS and the UE may predefine that UE-specific DCI indicating the end of the accumulation of a value of δPUCCH (i.e., PDCCH-<NUM> that includes UE-specific DCI including information about transmission of the PUCCH-<NUM> to be currently transmitted) will be transmitted only from PCell. The BS and the UE may predefine that, when the UE-specific DCI transmitted from the PCell does not exist, UE-specific DCI transmitted from particular SCell indicates the end of the accumulation of a value of δPUCCH. In this case, the BS and the UE may predefine that the particular SCell is a cell having a lowest cell index (or a cell having a highest cell index) from among SCells.

As another example, the BS may configure the UE with a cell index indicating the end of accumulation of a value of δPUCCH. Upon reception of this, the UE may accumulate a value of δPUCCH up to a point when reception of UE-specific DCI transmitted from a cell having the cell index ends.

In another example, the BS and the UE may predefine that the UE-specific DCI indicating the end of the accumulation of a value of δPUCCH will be transmitted from the same cell having a cell index from which the aforementioned UE-specific DCI indicating the start of the accumulation of a value of δPUCCH is transmitted.

In another example, the UE may start accumulation of a value of δPUCCH by a particular offset from the transmission start point of the immediately-before transmitted PUCCH (PUCCH-<NUM>) (or the transmission end point of PUCCH-<NUM>). For example, as shown in <FIG>, it is assumed that a transmission time of an immediately-before transmitted PUCCH (PUCCH-<NUM>) is a pth symbol of a jth slot and PUCCH-<NUM> includes L symbols. Also, it is assumed that an offset value is K symbols.

In this case, a UE may start accumulation of a value of δPUCCH before (or after) K symbols starting from the pth symbol of the jth slot (based on a transmission start point of the immediately-before transmitted PUCCH-<NUM>).

Alternatively, the UE may start accumulation of a value of δPUCCH before (or after) K symbols starting from a (p+L)th symbol of the jth slot (based on a transmission end point of the immediately-before transmitted PUCCH-<NUM>).

The offset value may be a predefined value, or a BS may configure the UE with the offset value via RRC signaling. Alternatively, based on a value configured by the BS, the UE may calculate the offset value.

According to an embodiment of the disclosure, the offset value is a symbol, but embodiments of the disclosure may be applied even when the offset value is a slot or a subframe.

An end of the accumulation of a value of δPUCCH may be performed up to a start of transmission of the currently transmitted PUCCH (PUCCH-<NUM>) or may be performed up to an offset with respect to the transmission of the currently transmitted PUCCH (PUCCH-<NUM>) as described with reference to <FIG> and <FIG>.

<FIG> illustrates an example where PDCCH-<NUM> is received after PUCCH-<NUM> is transmitted, and <FIG> illustrates an example where PDCCH-<NUM> is received before PUCCH-<NUM> is transmitted.

In another example, an end of accumulation of a value of δPUCCH may be performed at a point when reception of the PDCCH-<NUM> including information about PUCCH-<NUM> to be currently transmitted ends, as shown in <FIG>. Also, although not shown in <FIG>, accumulation of a value of δPUCCH may end at a point when reception of the PDCCH-<NUM> starts.

However, assuming that the accumulation of a value of δPUCCH starts and ends by using a method described above, when reception of PDCCH-<NUM> is performed before transmission of PUCCH-<NUM>, as shown in <FIG>, the UE may not be able to perform the accumulation of a values of δPUCCH. In this case, the UE may not accumulate a value of δPUCCH. That is, the value of δPUCCH may be configured as <NUM>.

With respect to accumulation of a value of δPUCCH, the UE may not use a start point of accumulation of a value of δPUCCH and an end point of accumulation of a value of δPUCCH but may use the start point of accumulation of a value of δPUCCH and a period in which accumulation of a value of δPUCCH is to be performed. In this case, it may be required to provide configuration as to how long the UE should perform accumulation of a value of δPUCCH. As an example therefor, the BS may configure, via RRC signaling, a value of a window. Upon reception of this, the UE may accumulate values of δPUCCH obtained from one or more DCls received from one or more cells, during a window period configured via RRC by the BS, the window starting from a point when reception of UE-specific DCI indicating a start of accumulation of values of δPUCCH is completed.

When there is no DCI received during a predefined window or a window period configured by the BS, the UE may configure the values of δPUCCH as <NUM> dB. By using an accumulated value of δPUCCH or a value of δPUCCH configured as <NUM> dB, the UE may update a value of g(i) by using [Equation <NUM>] (where i = n1+ k1 = n2 + k2 = n3 + k3). The UE may configure a transmission power value of the PUCCH to be transmitted on PCell, by using the updated value of g(i) and PUCCH resource information obtained from UE-specific DCI. Then, the UE may transmit the PUCCH in a (n1 + k1)th UL slot, by using the configured transmission power value of the PUCCH.

With reference to <FIG>, descriptions of the start point and end point of accumulation of values of δPUCCH for transmission of the PUCCH are provided, but the descriptions may be equally applied to a start point and end point of accumulation of values of δPUSCH for transmission of a PUSCH.

For example, PUCCH-<NUM> of <FIG> may be regarded as PUSCH-<NUM>, and PUCCH-<NUM> may be regarded as PUSCH-<NUM>. PDCCH-<NUM> may be regarded as UE-specific DCI including resource allocation information or the like about transmission of the PUSCH-<NUM>. In this case, the PUSCH-<NUM> may not be a PUSCH (grant-based PUSCH) being allocated via UE-specific DCI but may be a grant-free PUSCH configured via RRC.

In this case, the PDCCH-<NUM> may be received before the PUSCH-<NUM> is transmitted, and in this case, as described with reference to <FIG>, δPUSCH accumulation may be performed, transmission power of the PUSCH may be configured, and then the PUSCH may be transmitted.

<FIG> is a diagram for describing a start point and end point of accumulation of a value of δPUCCH, according to an embodiment of the disclosure.

Embodiments of using a start point and end point of accumulation of a value of δPUCCH have been described. In this case, as shown in <FIG>, an order of the start point and the end point may be switched. In another example, as shown in <FIG>, PDCCH-<NUM> may include resource allocation of PDSCH-<NUM> and transmission information of PUCCH-<NUM>, and PDCCH-<NUM> may include resource allocation of PDSCH-<NUM> and transmission information of PUCCH-<NUM>. As described with reference to <FIG>, <FIG>, and <FIG>, PDSCH-<NUM>/PDSCH-<NUM>/PUCCH-<NUM>/PUCCH-<NUM> may include a different number of symbols, and different scheduling schemes of mini-slot-based scheduling or slot-based scheduling may be used.

Accordingly, as shown in <FIG>, after a UE receives a PDCCH (PDCCH-<NUM>) including information about a PUCCH (PUCCH-<NUM>) to be currently transmitted, the UE may receive a PDCCH (PDCCH-<NUM>) including information about a pre-transmitted PUCCH (PUCCH-<NUM>).

In this case, as shown in <FIG>, when a start point of accumulation of a value of δPUCCH and an end point of accumulation of a value of δPUCCH are used, an order of the start point and the end point may be switched. In this case, the UE may not perform accumulation of a value of δPUCCH. That is, the value of δPUCCH may be configured as <NUM>.

Also, according to embodiments of informing a start point and an end point of accumulation of a value of δPUCCH, a start point and an end point of accumulation may be equal to each other. In this case, the UE may accumulate values of δPUCCH obtained from one or more DCIs received at the start point of accumulation of a value of δPUCCH(or the end point of accumulation of a value of δPUCCH), by using the method in the embodiments described above.

Embodiments where a start point of accumulation of a value of δPUCCH and an accumulation window period are used have been described. In this case, there may be a case where the accumulation window period is <NUM> (i.e., only the start point of accumulation of a value of δPUCCH is received). In this case, the UE may accumulate values of δPUCCH obtained from one or more DCIs received only at the start point of accumulation of a value of δPUCCH, by using the method in the embodiments described above. In another example, when the accumulation window period is <NUM>, the UE may not perform accumulation of a value of δPUCCH (i.e., the value of δPUCCH may be configured as <NUM>).

Also, with reference to <FIG>, a method of accumulating values of δPUCCH, when the UE receives two or more DCls from one or more cells in a CA environment, has been described. However, the disclosure is not limited to the environment and may be applied even when two or more DCls are received from one cell.

When the UE receives one DCI or two or more DCIs from one cell or two or more cells in a system to which CA is applied, by using a UL transmission power control method according to the disclosure, the UE may assure UL performance by accumulating values of transmission power control parameters obtained from the DCIs and may minimize interference to an adjacent cell.

<FIG> is a diagram for describing a PDCCH monitoring occasion of a UE in a single cell, according to an embodiment of the disclosure.

A PDCCH monitoring occasion refers to a time/frequency domain in which a UE may receive a PDCCH, and may be associated with a PDCCH search space. The UE may be configured with the PDCCH monitoring occasion through an RRC parameter from a BS. Referring to <FIG>, in a slot index n, one PDCCH monitoring occasion may exist in one slot; and in a slot index n + k (where k ≥ <NUM>), two PDCCH monitoring occasions may exist in one slot. That is, a different number of PDCCH monitoring occasions may exist in each slot. Although up to two PDCCH monitoring occasions exist in one slot in <FIG>, the disclosure is not limited thereto (i.e., three or more PDCCH monitoring occasions may exist in one slot). PDCCH monitoring occasion configuration information may include at least one of time axis information such as a start slot, a start symbol, or a period of a PDCCH monitoring occasion, or frequency axis information (e.g., a position of the PDCCH monitoring occasion along a frequency axis). When a plurality of PDCCH monitoring occasions are configured for one UE, PDCCH monitoring occasion configuration information may be applied to each PDCCH monitoring occasion. A UE receiving PDCCH monitoring occasion configuration information from a BS may monitor a PDCCH to be received by the UE in a corresponding PDCCH monitoring occasion. Although a PDCCH is transmitted in all PDCCH monitoring occasions in <FIG>, a PDCCH may not be transmitted in a region configured as a PDCCH monitoring occasion. The UE may not know when a PDCCH to be received by the UE is transmitted in a PDCCH monitoring occasion configured from the BS. Accordingly, the UE should monitoring the configured PDCCH monitoring occasion, and should always check whether the PDCCH to be received by the UE has been transmitted. Also, although not shown in <FIG>, when a PDCCH is transmitted through a PDCCH monitoring occasion in <FIG> it may mean that the PDCCH is transmitted within an activated bandwidth part (BWP). In this case, the BWP may be located in a system bandwidth operated by the BS (i.e., the BWP is a subset of the system bandwidth), and a plurality of BWPs may be configured for one UE in the system bandwidth. For example, the BS may configure four BWPs for one UE via RRC, and may activate one of the four configured BWPs. The UE may perform UL and DL transmission/reception only in the activated BWP from among the plurality of configured BWPs (i.e., the UE may not be able to simultaneously perform UL and DL transmission/reception in two or more BWPs).

<FIG> is a diagram for describing a PDCCH monitoring occasion of a UE in a CA environment, according to an embodiment of the disclosure.

<FIG> illustrates a PDCCH monitoring occasion of a UE in a CA environment including three CCs. Two PDCCH monitoring occasions are configured in a slot n, and three PDCCH monitoring occasions are configured in a slot n + k (where k ≥ <NUM>). In a CA environment, one PDCCH monitoring occasion may span all CCs constituting a CA system. That is, a first PDCCH monitoring occasion in the slot n of <FIG> may be applied to CC#<NUM>, CC#<NUM>, and CC#<NUM>. Accordingly, the UE configured with the first PDCCH monitoring occasion should check whether a PDCCH to be received by the UE is transmitted by monitoring the first PDCCH monitoring occasion spanning CC#<NUM>, CC#<NUM>, and CC#<NUM>, as shown in <FIG>. The above operation of the UE may be applied to first, second, and third PDCCH monitoring occasions in the slot n, and may also be applied to first, second, and third PDCCH monitoring occasions in the slot n + k. Although the CA system includes three CCs in <FIG>, the above operation may be equally applied to a CA system including four or more CCs. Although not shown in <FIG>, when a PDCCH is transmitted in a PDCCH monitoring occasion of each CC in <FIG>, it may mean that the PDCCH is transmitted within an activated BWP of each CC.

<FIG> is a diagram for describing a method by which a UE determines a PUCCH resource in a UL CA environment, according to an embodiment of the disclosure.

In UL CA, a UE may transmit a PUCCH only on PCell or simultaneously on both PCell and S-Pcell according to configuration of a BS. In <FIG>, the UE may transmit the PUCCH in CC#<NUM>. In this case, CC#<NUM> may be considered as PCell or S-PCell.

As another example for preventing an increase in power consumption of the UE and an increase in interference to an adjacent cell, there may be a method by which the UE follows a TPC command included in DCI indicating PUCCH resource information.

Referring to <FIG>, the UE may receive PDCCHs (PDCCH-A and PDCCH-B in <FIG>) transmitted from CC#<NUM> and CC#<NUM> in a first PDCCH monitoring occasion of a slot n, and may receive a PDCCH (PDCCH-C in <FIG>) transmitted from CC#<NUM> in a second PDCCH monitoring occasion of the slot n. Also, the UE may receive a PDCCH (PDCCH-D in <FIG>) transmitted from CC#<NUM> in a first PDCCH monitoring occasion of a slot n + k (where k ≥<NUM>), and may receive PDCCHs (PDCCH-E and PDCCH-F in <FIG>) transmitted from CC#<NUM> and CC#<NUM> in a second PDCCH monitoring occasion. In this case, it may be assumed that the UE succeeds in detecting all of the six PDCCHs (i.e., PDCCH-A, PDCCH-B, PDCCH-C, PDCCH-D, PDCCH-E, and PDCCH-F), and it may be assumed that all of the PDCCHs correspond to DCI format 1_0 or DCI format 1_1 in which a PUCCH may be scheduled. In this case, DCI transmitted to PDCCH-X may be defined as DCI-X (where X ∈ {A, B, C, D, E}).

DCI format 1_0 or DCI format 1_1 may include the following information.

As shown in <FIG>, six DCIs (or six PDCCHs) received by the UE in the slot n and the slot n + k may each indicate to transmit HARQ feedback in a slot n + k + l (where k ≥<NUM>, l ≥<NUM>). Also, bit fields indicating PUCCH resource information included in the six DCls may be different from each other (i.e., at least one DCI from among the six DCls may indicate a different PUCCH resource). In this case, there may occur ambiguity in which the UE does not know a PUCCH resource on which HARQ feedback should be transmitted. Also, there may occur ambiguity in which the BS does not know a PUCCH resource on which the UE transmits HARQ feedback.

In order to solve these problems, a predefined rule is required between the BS and the UE, and at least one of the following methods may be used.

<FIG>, <FIG>, <FIG>, and <FIG> are diagrams for describing a start point and an end point of accumulation of a value of δPUCCH, according to an embodiment of the disclosure. As described with reference to <FIG>, a UE should recognize a start point and an end point of accumulation in order to accumulate values of δPUCCH. <FIG>, <FIG>, <FIG>, and <FIG> are other examples thereof. In <FIG>, <FIG>, <FIG>, and <FIG>, a PUCCH that is to be currently transmitted is defined as a PUCCH (i.e., PUCCH-i) in an ith transmission occasion, and a PUCCH transmitted immediately before PUCCH-i is defined as a PUCCH (i.e., PUCCH-(i - i<NUM>)) in a (i - i<NUM>)th transmission occasion. In this case, the UE may obtain a value of δPUCCH from DCI format 2_2 transmitted after being CRC scrambled by TPC-PUCCH-RNTI, or may be obtained from DCI format 1_0 or DCI format 1_1 transmitted after being CRC scrambled by C-RNTI. A start point of accumulation of values of δPUCCH which should be accumulated for transmission of the PUCCH-i may be A in <FIG>, and an end point of accumulation may be B in <FIG>. That is, the UE may accumulate all values of δPUCCH obtained from the start point A to the end point B. In <FIG>, A that is the start point of accumulation of values of δPUCCH may refer to previous KPUCCH(i - i<NUM>) - <NUM> symbols before a start symbol of the PUCCH-(i - i<NUM>). Also, B that is the end point of accumulation of values of δPUCCH may refer to previous KPUCCH(i) symbols before a start symbol of the PUCCH-i.

The number of symbols constituting KPUCCH(i - i<NUM>) and KPUCCH(i) may vary according to a reception time point of DCI for scheduling a PUCCH and a transmission time point of the PUCCH. For example, a PDCCH through which DCI for scheduling the PUCCH-(i - i<NUM>) is transmitted may be defined as PDCCH-<NUM>, and a PDCCH through which DCI for scheduling the PUCCH-i is transmitted may be defined as PDCCH-<NUM>. In this case, when reception time points of PDCCHs and transmission time points of PUCCHs are sequentially arranged, there may be the following cases.

A start point and an end point of accumulation of values of δPUCCH in Case <NUM>) and Case <NUM>) will be described in more detail with reference to <FIG>.

In another example, the number of symbols constituting the KPUCCH(i - i<NUM>) and the KPUCCH(i) may vary according to whether the PUCCH-(i - i<NUM>) and the PUCCH-i are scheduled and transmitted by DCI format 1_0 or DCI format 1_1, or are transmitted by RRC configuration (e.g., transmission of a PUCCH that transmits feedback on downlink semi-persistent scheduling (SPS)) without being scheduled by DCI format 1_0 or DCI format 1_1. In more detail, there may be the following cases, according to whether the PUCCH transmission is scheduled by a PDCCH through which DCI format 1_0 or DCI format 1_1 is transmitted.

When the PUCCH-(i - i<NUM>) is scheduled and transmitted by DCI format 1_0 or DCI format 1_1, the KPUCCH(i - i<NUM>) may refer to the number of all symbols from a last received symbol of a PDCCH through which DCI format 1_0 or DCI format 1_1 is transmitted to a first symbol of the PUCCH-(i - i<NUM>). Likewise, the KPUCCH(i) may refer to the number of all symbols from the last received symbol of the PDCCH through which by DCI format 1_0 or DCI format 1_1 is transmitted to a first symbol of the PUCCH-i. For a PUCCH that is not scheduled and transmitted by DCI format 1_0 or DCI format 1_1, the KPUCCH(i - i<NUM>) and the KPUCCH(i) may each be defined as <NUM> x k2 and may be expressed as KPUCCH,min. In this case, a value of k2 may be provided to the UE via RRC, and specifically, may refer to a minimum value from among values of k2 which may be configured in a PUSCH-ConfigCommon parameter. As described above, a start point and an end point of accumulation of values of δPUCCH may vary according to whether PUCCH transmission is scheduled by a PDCCH through which DCI format 1_0 or DCI format 1_1 is transmitted, which will be described in more detail with reference to <FIG>.

<FIG> is a diagram for describing a start point and an end point of accumulation of values of δPUCCH, according to an embodiment of the disclosure.

In <FIG>, both PUCCH-(i - i<NUM>) and PUCCH-(i) are scheduled and transmitted by DCI format 1_0 or DCI format 1_1, and a PDCCH through which DCI for scheduling the PUCCH-(i - i<NUM>) is transmitted is expressed as PDCCH-<NUM> and a PDCCH through which DCI for scheduling the PUCCH-i is transmitted is expressed as PDCCH-<NUM>. As described with reference to <FIG>, there may be Case-<NUM> and Case-<NUM> according to a reception time point of a PDCCH and a transmission time point of a PUCCH. As shown in <FIG>, in Case-<NUM> and Case-<NUM>, KPUCCH(i - i<NUM>) may refer to the number of all symbols from a last received symbol of the PDCCH-<NUM> to a first symbol of the PUCCH-(i - i<NUM>), and KPUCCH(i) may refer to the number of all symbols from a last received symbol of the PDCCH-<NUM> to a first symbol of the PUCCH-i. Accordingly, in <FIG>, the UE may accumulate all values of δPUCCH received from a symbol (A) next to a last symbol of the PDCCH-<NUM> to the last received symbol (B) of the PDCCH-<NUM>.

Although a start point and an end point of accumulation of values of δPUCCH for PUCCH transmission have been described in <FIG>, the same description may be applied to a start point and an end point of accumulation of values of δPUSCH for PUSCH transmission. For example, when both the PUSCH-(i - i<NUM>) and the PUSCH-(i) are scheduled and transmitted by DCI format 2_0 or DCI format 2_1, a PDCCH through which DCI for scheduling PUSCH-(i - i<NUM>) is transmitted may be considered as PDCCH-<NUM>, and a PDCCH through which DCI for scheduling PUSCH-i may be considered as PDCCH-<NUM>. In this case, the UE may accumulate all values of δPUSCH received from a symbol (A) next to a last symbol of the PDCCH-<NUM> to a last received symbol (B) of the PDCCH-<NUM>.

In <FIG>, when DCI is transmitted from different cells and the UE detects a plurality of DCls, the UE may transmit a PUCCH on a PUCCH resource indicated by DCI received from a cell having a lowest cell index from among most recently received DCls, or may transmit a PUCCH in a PUCCH resource indicated by DCI received from a cell having a highest cell index from among the most recently received DCIs. It may be necessary to consider such a method of determining DCI indicating PUCCH resource information in association with a method of accumulating values of δPUCCH. In more detail, in <FIG>, the UE may obtain resource information for PUCCH transmission through a PUCCH resource information indicator of DCI-F. Although <FIG> is described assuming a single cell, a start point A and an end point B for accumulation of values of δPUCCH may be applied even when multiple cells are used. In this case, DCI indicating resource information of PUCCH-(i - i<NUM>) may indicate the start point A of <FIG>, and DCI indicating resource information of PUCCH-i may indicate the end point B of <FIG>. For example, DCI-F of <FIG> may be considered as PDCCH-<NUM> of <FIG>. Although not shown in <FIG>, PDCCH-<NUM> of <FIG> may be one of DCI-A, DCI-B, or DCI-C for scheduling PUCCH transmission transmitted between a slot n and a slot n + k in <FIG> (Case-<NUM> in <FIG>). Alternatively, the PDCCH-<NUM> of <FIG> may be one of DCI-A, DCI-B, DCI-C, DCI-D, or DCI-E for scheduling PUCCH transmission transmitted between the slot n + k and a slot n + k + I in <FIG> (Case-<NUM> in <FIG>). Accordingly, according to the description of <FIG>, the UE may accumulate values of δPUCCH by using a PUCCH resource indicator used for PUCCH transmission. For example, accumulation of values of δPUCCH may be accumulation of values of δPUCCH included in all DCls (i.e., DCI format 2_2 transmitted after being CRC scrambled by TPC-PUCCH-RNTI and DCI format 1_0 or DCI format 1_1 transmitted after being CRC scrambled by C-RNTI) received from all cells between DCI-A (when the PDCCH-<NUM> of <FIG> is assumed as DCI-A of <FIG>) and DCI-F (when the PDCCH-<NUM> of <FIG> is assumed as DCI-F of <FIG>).

However, in this case, as the number of accumulated values of δPUCCH increases, the UE may unnecessarily configure high transmission power, thereby increasing power consumption of the UE and increasing the amount of interference to an adjacent cell. In order to solve the problems, a BS may configure values of δPUCCH included in DCls transmitted from some cells as <NUM> dB. Alternatively, the BS may configure a sum of accumulated values of δPUCCH included in DCls as <NUM> dB. For example, the BS may configure a sum of accumulation as <NUM> dB by configuring values of δPUCCH included in DCls transmitted from some cells as -<NUM> dB and configuring values of δPUCCH included in DCls transmitted from some cells as +<NUM> dB. In another example, when a combination of values of δPUCCH is configured as -<NUM> dB, -<NUM> dB, -<NUM> dB, and +<NUM> dB, a sum of accumulation may be <NUM> dB.

Unlike in <FIG>, in <FIG>, PUCCH-(i - i<NUM>) is not scheduled by DCI, and PUCCH-(i) is scheduled and transmitted by DCI (Case-<NUM>). In this case, there may be two additional cases as shown in <FIG>, according to a transmission time point of the PUCCH-(i - i<NUM>) and a reception time point of PDCCH-<NUM>. A case where a transmission time point of the PUCCH-(i - i<NUM>) is earlier than a reception time point of the PDCCH-<NUM> is expressed as Case-<NUM>(a), and a case where a transmission time point of the PUCCH-(i - i<NUM>) is later than a reception time point of the PDCCH-<NUM> is expressed as Case-<NUM>(b). As described with reference to <FIG>, in Case-<NUM>(a) and Case-<NUM>(b), KPUCCH(i - i<NUM>) may refer to KPUCCH,min before a first symbol of the PUCCH-(i - i<NUM>), and KPUCCH(i) may refer to the number of all symbols from a last received symbol of the PDCCH-<NUM> to a first symbol of the PUCCH-i. Accordingly, in <FIG>, the UE may accumulate all values of δPUCCH received from a KPUCCH,min - <NUM> symbol (A) with respect to the first symbol of the PUCCH-(i - i<NUM>) to the last received symbol (B) of the PDCCH-<NUM>.

Although a start point and an end point of accumulation of values of δPUCCH for PUCCH transmission have been described in <FIG>, the same description may be applied to a start point and an end pint of accumulation of values of δPUSCH for PUSCH transmission. For example, in <FIG>, PUSCH-(i - i<NUM>) may not be scheduled by DCI, and PUSCH-(i) may be scheduled and transmitted by DCI. In this case, the UE may accumulate all values of δPUSCH received from a KPUSCH,min - <NUM> symbol (A) with respect to a first symbol of the PUSCH-(i - i<NUM>) to a last received symbol (B) of PDCCH-<NUM>.

In <FIG>, when DCI is transmitted from different cells and the UE detects a plurality of DCls, the UE may transmit a PUCCH on a PUCCH resource indicated by DCI received from a cell having a lowest cell index from among most recently received DCls, or may transmit a PUCCH in a PUCCH resource indicated by DCI received from a cell having a highest cell index from among the most recently received DCIs. It may be necessary to consider such a method of determining DCI indicating PUCCH resource information in association with a method of accumulating values of δPUCCH. In more detail, in <FIG>, the UE may obtain resource information for PUCCH transmission through a PUCCH resource information indicator of DCI-F. Although 21B is described assuming a single cell, a start point A and an end point B for accumulation of values of δPUCCH may be applied even when multiple cells are used. In this case, as described with reference to <FIG>, DCI indicating PUCCH resource information may refer to the end point B of <FIG>. For example, DCI-F of <FIG> may be considered as PDCCH-<NUM> of <FIG>. Although not shown in <FIG>, the PUCCH-(i - i<NUM>) of <FIG> may be transmitted between a slot n and a slot n + k in <FIG> (Case-<NUM>(a) <FIG>). Alternatively, the PUCCH-(i - i<NUM>) of <FIG> may be transmitted between the slot n + k and a slot n + k + l in <FIG> (Case-<NUM>(b) in <FIG>). Accordingly, according to the description of <FIG>, although the UE transmits a PUCCH by using a PUCCH resource indicator obtained from DCI-F, accumulation of values of δPUCCH may be accumulation of values of δPUCCH included in all DCls (i.e., DCI format 2_2 transmitted after being CRC scrambled by TPC-PUCCH-RNTI and DCI format 1_0 or DCI format 1_1 transmitted after being CRC scrambled by C-RNTI) received from all cells between a KPUSCH,min - <NUM> symbol (A) before the PUCCH-(i - i<NUM>) and DCI-F (when the PDCCH-<NUM> of <FIG> is assumed as DCI-F of <FIG>). In this case, as the number of accumulated values of δPUCCH increases, the UE may unnecessarily configure high transmission power, thereby increasing power consumption of the UE and increasing the amount of interference to an adjacent cell. In order to solve the problems, the BS may configure values of δPUCCH included in DCIs transmitted from some cells as <NUM> dB. Alternatively, the BS may configure a sum of accumulated values of δPUCCH included in DCIs as <NUM> dB. For example, the BS may configure a sum of accumulation as <NUM> dB by configuring values of δPUCCH included in DCIs transmitted from some cells as -<NUM> dB and configuring values of δPUCCH included in DCls transmitted from some cells as +<NUM> dB. In another example, when a combination of values of δPUCCH is configured as -<NUM> dB, -<NUM> dB, -<NUM> dB, and +<NUM> dB, a sum of accumulation may be <NUM> dB.

<FIG> is a diagram for describing a start point and an end pint of accumulation of values of δPUCCH, according to an embodiment of the disclosure.

Unlike in <FIG>, in <FIG>, both PUCCH-(i - i<NUM>) and PUCCH-(i) are not scheduled by DCI. In this case, as described with reference to <FIG>, KPUCCH(i - i<NUM>) may refer to KPUCCH,min before a first symbol of the PUCCH-(i - i<NUM>), and KPUCCH(i) may refer to KPUCCH,min before a first symbol of the PUCCH-i. Accordingly, in <FIG>, the UE may accumulate all values of δPUCCH received from a KPUCCH,min - <NUM> symbol (A) with respect to the first symbol of the PUCCH-(i - i<NUM>) to a KPUCCH,min - <NUM> symbol (B) with respect to the first symbol of the PUCCH-i.

Although a start point and an end point of accumulation of values of δPUCCH for PUCCH transmission have been described with reference to <FIG>, the same description may be applied to a start point and an end point of accumulation of values of δPUSCH for PUSCH transmission. For example, in <FIG>, both PUSCH-(i - i<NUM>) and PUSCH-(i) may not be scheduled by DCI. In this case, the UE may accumulate all values of δPUSCH received from a KPUSCH,min - <NUM> symbol (A) with respect to a first symbol of the PUSCH-(i - i<NUM>) to a KPUSCH,min - <NUM> symbol (B) with respect to a first symbol of the PUSCH-i.

<FIG> illustrates an example of a system for describing some embodiments of the disclosure.

For convenience of explanation, <FIG> illustrates a V2X system including two UEs (UE-<NUM> and UE-<NUM>), but the disclosure is not limited thereto. Also, a UL and a DL between a BS and V2X UEs may each be called a Uu interface, and a SL between the V2X UEs may be called a PC5 interface. Accordingly, they may be interchangeably used in the disclosure. In the disclosure, a UE may refer to a vehicle that supports vehicle-to-vehicle (V2V) communication, a vehicle or a pedestrian's handset (i.e., a smartphone) which supports vehicle-to-pedestrian (V2P) communication, a vehicle that supports vehicle-to-network (V2N) communication, or a vehicle that supports vehicle-to-infrastructure (V2I) communication. Also, in the disclosure, a UE may refer to a road side unit (RSU) having UE functions, an RSU having BS functions, or an RSU having some BS functions and some UE functions. Also, it is predefined that, in the disclosure, a BS is a BS that supports both V2X communication and general cellular communication or that supports only V2X communication. In this case, the BS may refer to a <NUM> BS (gNB), a <NUM> BS (eNB), or a road side unit (RSU). Accordingly, unless otherwise stated in the disclosure, a BS and an RSU may be the same concept, and thus, may be interchangeably used.

<FIG> illustrates a procedure in which a BS controls transmission power of a UE in a cellular system, according to some embodiments of the disclosure.

The UE within coverage of the BS may perform DL synchronization with the BS and may obtain system information. According to some embodiments of the disclosure, the DL synchronization may be performed through a primary synchronization signal/secondary synchronization signal (PSS/SSS) received from the BS. The UE having performed the DL synchronization may receive a master information block (MIB) and a system information block (SIB) and obtain the system information from the BS. The UE may perform a random access procedure to perform UL synchronization with the BS. In the random access procedure, the UE may transmit a random access preamble and a message <NUM> (msg3) to the BS via a UL. In this case, UL transmission power control may be performed in the transmission of the random access preamble and the transmission of the message <NUM>, and the UE may receive parameters for UL transmission power control from the BS via an SIB or may use predefined parameters.

The UE may measure reference signal received power (RSRP) from a path attenuation estimation signal transmitted by the BS and may estimate a DL path attenuation value as in [Equation <NUM>]. Then, based on the estimated DL path attenuation value, the UE may configure a UL transmission power value for transmitting the random access preamble and the message <NUM>.

In [Equation <NUM>], the transmission power of the BS signal refers to transmission power of a DL path attenuation estimation signal transmitted by the BS. The DL path attenuation estimation signal transmitted by the BS may be a cell-specific reference signal (CRS) or a synchronization signal block (SSB). When the path attenuation estimation signal is a CRS, the transmission power of the BS signal may refer to transmission power of the CRS, and may be transmitted to the UE via a referenceSignalPower parameter of the system information. When the path attenuation estimation signal is an SSB, the transmission power of the BS signal may refer to transmission power of a secondary synchronization signal (SSS) and a demodulation reference signal (DMRS) that is transmitted via a physical broadcast channel (PBCH), and may be transmitted to the UE via an ss-PBCH-BlockPower parameter.

When RRC connection is established, the UE may receive, from the BS, RRC parameters for UL transmission power control via UE-specific RRC signaling or common RRC signaling. The received transmission power control parameters may be different from each other according to types of UL channels and types of signals. That is, transmission power control parameters to be applied to transmission of a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), and a sounding reference signal (SRS) may be different from each other. Also, as described above, a transmission power control parameter the UE received from the BS via a SIB before RRC connection establishment or transmission power control parameters the UE used as a predefined value before the RRC connection establishment may be included in the RRC parameters that are transmitted from the BS after the RRC connection establishment. In this case, the UE may use an RRC parameter value so as to control UL transmission power, the RRC parameter value being received from the BS after the RRC connection establishment.

Also, after the RRC connection establishment with the UE, the BS may configure a channel state information-reference signal (CSI-RS) as a path attenuation estimation signal for the UE. In this case, the BS may transmit, to the UE, information about transmission power of the CSI-RS via a powerControlOffsetSS parameter of UE dedicated RRC information. In this case, powerControlOffsetSS may indicate a transmission power offset between the SSB and the CSI-RS.

The UE may measure a DL RSRP by using the CSI-RS, and may estimate the DL path attenuation value by using [Equation <NUM>] by using the information about the transmission power of the CSI-RS received from the BS. Then, based on the estimated DL path attenuation value, the UE may configure the UL transmission power value for PUCCH, PUSCH, and SRS transmission.

The UE may report a power headroom (PH) to the BS. The power headroom may refer to a difference between current transmission power of the UE and maximum output power of the UE. The BS may use the power headroom report received from the UE to optimize a system operation. For example, when a value of a power headroom a particular UE reports to the BS is a positive value, the BS may allocate more resource blocks (RBs) to the particular UE, thereby increasing system yield. In contrast, when a value of a power headroom a particular UE reports to the BS is a negative value, the BS may allocates fewer resources to the particular UE or may reduce transmission power of the particular UE via a transmission power control (TPC) command. By doing so, the BS may increase system yield or may reduce unnecessary power consumption by the UE.

The UE receiving the TPC command from the BS may reduce, increase, or maintain transmission power as indicated by the TPC command (transmission power update). In this case, the TPC command may be transmitted to the UE via UE-specific DCI or group common DCI. Accordingly, the BS may dynamically control transmission power of the UE via the TPC command.

<FIG> illustrates a procedure in which a BS controls transmission power of a UE in a cellular system, according to some embodiments of the disclosure;.

A UE may be allocated a resource for separate sidelink communication from a BS (e.g., gNB/eNB/RSU, referred to as a BS) in order to perform sidelink communication with another UE, or may select a resource for sidelink communication without intervention of the BS. <FIG> illustrates a process in which UE-<NUM> is allocated a separate sidelink resource from a BS in order to perform sidelink communication with UE-<NUM>. In detail, the BS may schedule a PDCCH for sidelink communication to the UE-<NUM>. DCI information (e.g., DCI format 3_0) transmitted to the UE-<NUM> through the PDCCH may include at least one of the following.

The UE-<NUM> receiving the DCI formation information in the PDCCH may obtain PSCCH (or PSSCH) resource information to be transmitted or received to or from the UE-<NUM>. Also, the UE-<NUM> may obtain PSFCH information from the UE-<NUM>. The UE-<NUM> may perform sidelink transmission or reception through the PSCCH (or PSSCH) resource information and the PSFCH information. Also, the UE-<NUM> receiving the PSFCH information may transmit the PSFCH information as HARQ feedback to the BS through the PUCCH or the PUSCH. When transmission or reception relationships of physical channels shown in <FIG> are sequentially described, first, the BS may transmit the PDCCH to the UE-<NUM> (step <NUM>). The UE-<NUM> may transmit the PSCCH (or PSSCH) to the UE-<NUM> (step <NUM>). The UE-<NUM> may transmit the PSFCH to the UE-<NUM> (step <NUM>). The UE-<NUM> may transmit the PUCCH to the BS (step <NUM>). A transmission or reception flow of physical channels according to an embodiment of the disclosure may include the above steps. However, according to an embodiment, some of the above steps may be omitted, and other steps may be added. For example, in the above steps, step <NUM> or step <NUM> may be omitted by a higher layer signal or an L1 signal. In another example, step <NUM> may be omitted by a specific combination of some fields (e.g., the PSFCH-to-HARQ feedback timing indicator and the PUCCH resource indicator) from among the fields of the DCI format. That is, the UE-<NUM> may not transmit the HARQ feedback information to the BS, based on a specific combination of some fields from among the fields of the DCI format. For example, when both the PSFCH-to-HARQ feedback timing indicator and the PUCCH resource indicator indicate a value of <NUM>, the UE-<NUM> does not transmit the HARQ feedback information to the BS.

Transmission power control of a physical uplink control channel (PUCCH) of a wireless communication system (e.g., an NR (<NUM>) communication system) is as shown in [Equation <NUM>].

i<NUM> has been described with reference to <FIG>, and may be equally defined in [Equation <NUM>]. C(ci) is the total number of transmission power control (TPC) commands received by the UE between lth PUCCH transmission and (i-i<NUM>)th PUCCH transmission. δPUCCH,b,f,c(m,l) may refer to a TPC command value for the specific closed-loop power control index I on the serving cell c, the carrier f, and the BWP b. δPUCCH,b,f,c(m,l) may be indicated by a UE-common DCI format (e.g., DCI format 2_3) or a UE-specific DCI format (e.g., DCI format 1_0, 1_1, or 1_2). Also, according to an embodiment, δPUCCH,b,f,c(m,l) may have values as shown in [Table <NUM>].

The UE may determine transmission power for transmitting a PUCCH as described above in [Equation <NUM>] and [Equation <NUM>]. However, a field (e.g., a TPC command) related to PUCCH transmission power may not exist in a DCI format (e.g., DCI format 3_0) indicating allocation of a sidelink resource (e.g., PSCCH/PSSCH or PSFCH) for communication between UE-<NUM> and UE-<NUM>. In a situation where there is no field related to PUCCH transmission power, the UE may determine transmission power by using at least one of the following methods or a combination thereof.

In another example, because I in δPUCCH,b,f,c(i,l) denotes a closed-loop index (corresponding to the specific closed-loop power control index), the UE may adjust transmission power by independently (or individually) configuring a plurality of closed-loop indexes. The UE receiving control information having no TPC command may always consider the value of I as a fixed value of <NUM> or <NUM>, or may determine the value of I (closed-loop index value) by considering a value of I associated with a PUCCH resource indicated by a separate PUCCH resource indicator.

<FIG> is a flowchart illustrating PUCCH transmission power determination of a UE, according to an embodiment.

As described with reference to <FIG>, UE-<NUM> may receive DCI information (hereinafter, referred to as DCI information for sidelink communication) including sidelink resource allocation information and PUCCH resource information from a BS (<NUM>). The UE-<NUM> may transmit a PSCCH and a PSSCH to UE-<NUM> on a sidelink resource allocated based on the DCI information for sidelink communication (<NUM>). When a sidelink communication resource pool includes a PSFCH, the UE-<NUM> may receive HARQ feedback information from the UE-<NUM> (<NUM>). The UE-<NUM> may transmit the HARQ feedback information received through the PSFCH on a PUCCH resource provided by the DCI information for sidelink communication (<NUM>). In this case, transmission power is determined by at least one of the methods described with reference to <FIG> or a combination of some of the methods.

<FIG> illustrates a structure of a UE, according to an embodiment of the disclosure.

Referring to <FIG>, a UE may include a processor <NUM>, a transceiver <NUM>, and a memory <NUM>. In the disclosure, the processor <NUM> may be defined as a circuit, an application-specific integrated circuit, or at least one processor.

The UE of <FIG> may correspond to UE-<NUM> as well as UE-<NUM> of <FIG>. Also, the UE of <FIG> may correspond to UE-<NUM> of <FIG> and may also correspond to UE-<NUM>.

The processor <NUM> according to an embodiment of the disclosure may control an overall operation of the UE. For example, the processor <NUM> may control a signal flow between blocks so as to perform operations according to flowcharts described above. Also, the processor <NUM> may write data to and read data from the memory <NUM>. The processor <NUM> may perform functions of a protocol stack which are required by communication standards. To this end, the processor <NUM> may include at least one processor or a micro-processor. Alternatively, the processor <NUM> may be a part of another processor. Also, a part of the transceiver <NUM> and the processor <NUM> may be referred to as a communication processor (CP).

According to an embodiment of the disclosure, the processor <NUM> may control operations of the UE described with reference to <FIG>.

The processor <NUM> according to an embodiment of the disclosure may perform a UL transmission power control method, and thus, when the UE receives one or more DCls from one or more cells in a system to which CA is applied, the processor <NUM> may assure UL performance by accumulating values of transmission power control parameters obtained from the DCIs and may minimize interference to an adjacent cell.

The transceiver <NUM> according to an embodiment of the disclosure may perform functions for transmitting or receiving signals through a wireless channel. For example, the transceiver <NUM> may perform conversion between a baseband signal and a bit string based on physical layer specifications of a system. For example, for data transmission, the transceiver <NUM> may generate complex symbols by encoding and modulating a transmission bit string. For data reception, the transceiver <NUM> may reconstruct a reception bit string by demodulating and decoding a baseband signal. Also, the transceiver <NUM> may up-convert a baseband signal into a radio frequency (RF) band signal and then may transmit the RF band signal through an antenna, and may down-convert an RF band signal received through the antenna into a baseband signal. For example, the transceiver <NUM> may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital-to-analog convertor (DAC), an analog-to-digital convertor (ADC), or the like. Also, the transceiver <NUM> may include a plurality of transmission or reception paths. Furthermore, the transceiver <NUM> may include at least one antenna array including a plurality of antenna elements. In terms of hardware, the transceiver <NUM> may include a digital circuit and an analog circuit (e.g., a radio frequency integrated circuit (RFIC)). The digital circuit and analog circuit may be implemented in one package. Also, the transceiver <NUM> may include a plurality of RF chains.

The memory <NUM> according to an embodiment of the disclosure may store basic programs, application programs, and data, e.g., configuration information, for operations of the UE. The memory <NUM> may be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. The memory <NUM> may provide stored data, in response to a request by the processor <NUM>. The memory <NUM> may store at least one of information transmitted or received via the transceiver <NUM> or information generated by the processor <NUM>.

<FIG> illustrates a structure of a BS, according to an embodiment of the disclosure.

Referring to <FIG>, a BS may include a processor <NUM>, a transceiver <NUM>, and a memory <NUM>. In the disclosure, the processor <NUM> may be defined as a circuit, an application-specific integrated circuit, or at least one processor.

The processor <NUM> according to an embodiment of the disclosure may control an overall operation of the BS. For example, the processor <NUM> may control a signal flow between blocks so as to perform operations according to flowcharts described above. Also, the processor <NUM> may write data to and read data from the memory <NUM>. The processor <NUM> may perform functions of a protocol stack which are required by communication standards. To this end, the processor <NUM> may include at least one processor or a micro-processor. Alternatively, the processor <NUM> may be a part of another processor. Also, a part of the transceiver <NUM> and the processor <NUM> may be referred to as a CP.

According to an embodiment of the disclosure, the processor <NUM> may control operations of the BS described with reference to <FIG>.

The transceiver <NUM> according to an embodiment of the disclosure may perform functions for transmitting or receiving signals through a wireless channel. For example, the transceiver <NUM> may perform conversion between a baseband signal and a bit string based on physical layer specifications of a system. For example, for data transmission, the transceiver <NUM> may generate complex symbols by encoding and modulating a transmission bit string. For data reception, the transceiver <NUM> may reconstruct a reception bit string by demodulating and decoding a baseband signal. Also, the transceiver <NUM> may up-convert a baseband signal into an RF band signal and then may transmit the RF band signal through an antenna, and may down-convert an RF band signal received through the antenna into a baseband signal. For example, the transceiver <NUM> may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, or the like. Also, the transceiver <NUM> may include a plurality of transmission or reception paths. Furthermore, the transceiver <NUM> may include at least one antenna array including a plurality of antenna elements. In terms of hardware, the transceiver <NUM> may include a digital circuit and an analog circuit (e.g., a RFIC). The digital circuit and analog circuit may be implemented in one package. Also, the transceiver <NUM> may include a plurality of RF chains.

The memory <NUM> according to an embodiment of the disclosure may store basic programs, application programs, and data, e.g., configuration information, for operations of the BS. The memory <NUM> may be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. The memory <NUM> may provide stored data, in response to a request by the processor <NUM>. The memory <NUM> may store at least one of information transmitted or received via the transceiver <NUM> or information generated by the processor <NUM>.

Methods according to the claims of the disclosure or the embodiments described in the specification may be implemented by hardware, software, or a combination of hardware and software.

When the methods are implemented by software, a computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the computer-readable storage medium are configured to be executed by one or more processors in an electronic device. The one or more programs may include instructions for allowing the electronic device to execute the methods according to the claims of the disclosure or the embodiments described in the specification.

The programs (e.g., software modules or software) may be stored in a random-access memory (RAM), a non-volatile memory including a flash memory, a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic disc storage device, a compact disc-ROM (CD-ROM), a digital versatile disc (DVD), another optical storage device, or a magnetic cassette. Alternatively, the programs may be stored in a memory including any combination of some or all of the above storage media. Also, a plurality of constituent memories may be provided.

Also, the programs may be stored in an attachable storage device that is accessible through a communication network, such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN), or a storage area network (SAN), or a combination thereof. Such a storage device may be connected through an external port to an apparatus for performing an embodiment of the disclosure. Also, a separate storage device on a communication network may be connected to an apparatus for performing an embodiment of the disclosure.

In detailed embodiments of the disclosure, elements included in the disclosure have been expressed as singular or plural according to the detailed embodiments of the disclosure. However, the singular or plural form is selected appropriately for a condition provided for convenience of explanation, and the disclosure is not limited to the singular or plural form. An element expressed in a singular form may include a plurality of elements and elements expressed in a plural form may include a single element.

Claim 1:
An operating method of a first user equipment, UE, in a wireless communication system, the operating method comprising:
receiving (<NUM>) downlink control information, DCI, for sidelink communication, from a base station;
transmitting (<NUM>) a physical sidelink control channel, PSCCH, or a physical sidelink shared channel, PSSCH, to a second UE, based on the DCI for the sidelink communication;
receiving (<NUM>) hybrid automatic repeat and request, HARQ, feedback information through a physical sidelink feedback channel, PSFCH, from the second UE;
in case that a transmission power control, TPC, command field is not included in the DCI for the sidelink communication, determining a TPC command value as a configured value for a physical uplink control channel, PUCCH;
determining transmission power for transmitting the HARQ feedback information to the base station, based on the determined TPC command value; and
transmitting (<NUM>) the HARQ feedback information through the PUCCH to the base station, based on the determined transmission power.