Method and apparatus for allocating resources of physical uplink control channel in wireless communication system

Abstract

The present disclosure relates to a method and apparatus for efficiently allocating resources of a physical uplink control channel to a plurality of user equipment in a wireless communication system. According to an embodiment of the present disclosure, a method carried out by a base station for allocation of PUCCH resources in a wireless communication system may comprise the steps of: identifying indices of user equipment corresponding to the number of user equipment for allocation of PUCCH resources in a first format; selecting a cyclic shift (CS) for each user equipment by using a CS allocation scheme determined on the basis of an orthogonal sequence (OS) length, a CS distance, and a user equipment index of each user equipment to be allocated a PUCCH resource; selecting an OS for each user equipment on the basis of the OS length and the user equipment index of the user equipment to be allocated the PUCCH resource; and allocating a PUCCH resource in the first format to each user equipment on the basis of the selected CS and the selected OS.

Description

Method and apparatus for allocating resources of a physical uplink control channel in a wireless communication system

[0001] The present disclosure relates to a method and apparatus for allocating PUCCH resources in a wireless communication system.

[0002] To meet the increasing demand for wireless data traffic following the 4G system (i.e., the LTE (long-term evolution) system), 5G systems have been developed and commercialized. 5G systems can be implemented in the mmWave band. To mitigate path loss and increase the transmission distance of radio waves in the mmWave band, beamforming, massive array multiple input / output (massive MIMO), full-dimensional multiple input / output (Full Dimensional MIMO: FD-MIMO), array antenna, analog beamforming, and large-scale antenna technologies are being discussed for 5G systems.

[0003] In wireless communication systems such as 4G or 5G systems, the physical layer is responsible for converting actual data into electrical signals for transmission. For efficient communication, it is important to minimize data loss during the process of transmitting and receiving wireless signals at the physical layer. To this end, the physical layer selects an appropriate transmission method based on factors such as transmission speed, channel conditions, and noise levels. Transmission methods at the physical layer include channel coding, modulation / demodulation, multi-antenna processing techniques, and time-frequency resource allocation.

[0004] Additionally, at the physical layer, the transmission method includes a mapping between a physical channel and a transmission channel. A physical channel corresponds to a set of time / frequency resources used for transmission on a specific transmission channel. Physical channels are divided into downlink channels and uplink channels. In the description of this disclosure, an uplink (UL) refers to a wireless link through which a terminal (user equipment: UE) transmits data and / or control signals (e.g., uplink control information) to a base station, and a downlink (DL) may refer to a wireless link through which a base station transmits data and / or control signals (e.g., downlink control information) to a terminal.

[0005] In the following description, physical channel and signal may be used interchangeably with data or control signals. For example, PDSCH (physical downlink shared channel) is a term referring to the physical channel through which downlink data is transmitted, but PDSCH may be used to refer to downlink data. PUSCH (physical uplink shared channel) is a term referring to the physical channel through which uplink data is transmitted, but PUSCH may be used to refer to uplink data. PDCCH (physical downlink control channel) is a term referring to the physical channel through which downlink control information (DCI) is transmitted, but PDCCH may be used to refer to DCI. PUCCH (physical uplink control channel) is a term referring to the physical channel through which uplink control information (UCI) is transmitted, but PUCCH may be used to refer to uplink data. In the following description, the expression 'transmit / receive through a physical channel' may be interpreted as equivalent to the expression 'transmit / receive data or control signals through a physical channel'. DCI can be used to provide the terminal with information necessary for the proper reception and decoding of downlink data transmission. UCI can be used to provide information about the terminal's status to the scheduler and the HARQ (hybrid automatic repeat and request) protocol. This specification covers PUCCH.

[0006] A PUCCH is a channel used by a terminal to transmit control information to a base station. That is, a PUCCH is used by a terminal to transmit a UCI to a base station, and for example, a UCI may include channel state information (CSI), scheduling request (SR), HARQ ACK / NACK, and / or MU-MIMO (multiple user - multiple input multiple output) support information. In wireless communication systems such as 4G systems and / or 5G systems, the base station allocates PUCCH resources for each of multiple terminals to transmit a UCI via the PUCCH, and a method is required to efficiently allocate PUCCH resources so that UCIs can be received from multiple terminals without interference.

[0007] The present disclosure provides a method and apparatus for efficiently allocating resources of a physical uplink control channel to a plurality of terminals in a wireless communication system.

[0008] The present disclosure provides a resource allocation method and apparatus capable of reducing interference effects between resources of a physical uplink control channel in a wireless communication system.

[0009] The present disclosure provides a method and apparatus for efficiently allocating multiplexed PUCCH resources based on PUCCH format 1 in a wireless communication system.

[0010] According to an embodiment of the present disclosure, a base station in a wireless communication system comprises a transceiver, one or more processors including processing circuitry, and a memory for storing instructions. When the instructions are executed individually or collectively by the one or more processors, the base station may cause the base station to identify indices of the terminals corresponding to the number of terminals (user equipment: UE) for the allocation of a physical uplink control channel (PUCCH) resource of a first format. In one embodiment, when the instructions are executed individually or collectively by the one or more processors, the CS may be selected for each terminal using a CS allocation method determined based on an orthogonal sequence (OS) length, a cyclic shift (CS) distance, and the terminal index of each terminal to be allocated the PUCCH resource. In one embodiment, when the instructions are executed individually or collectively by the one or more processors, the OS may be selected for each terminal based on the OS length and the terminal index to be allocated the PUCCH resource. In one embodiment, when the above commands are executed individually or collectively by the one or more processors, they may cause the allocation of a PUCCH resource of the first format to each terminal based on the selected CS and the selected OS.

[0011] In one embodiment, the PUCCH resource of the first format may be multiplexed for the terminals within a single resource block (RB).

[0012] In one embodiment, when the commands are executed individually or collectively by the one or more processors (930), the base station may further cause the base station to transmit to each terminal, through the transceiver, configuration information including information about the selected CS and information about the selected OS for each terminal.

[0013] In one embodiment, when the commands are executed individually or collectively by the one or more processors, the base station may further cause to receive PUCCH signals from the first format-based multiplexed PUCCH resources allocated to the terminals based on the configuration information through the transceiver.

[0014] In one embodiment, when the above commands are executed individually or collectively by the one or more processors, the base station may be caused to determine the CS distance based on the number of terminals allocated PUCCH resources and the OS length.

[0015] In one embodiment, when the above commands are executed individually or collectively by the one or more processors, the base station may cause the base station to start CS allocation to each terminal by using the determined CS allocation method, maintaining the CS interval within the OS by the CS distance, and to allocate CS resources for each terminal by cycling through the OS by the length of the OS, which is NOS.

[0016] In one embodiment, when the above commands are executed individually or collectively by the one or more processors, the base station is configured to determine one of the first CS allocation method and the second CS allocation method as the CS allocation method based on the terminal index of each terminal, and the second CS allocation method may perform CS allocation among the CSs first allocated by the first CS allocation method.

[0017] In one embodiment, when the above commands are executed individually or collectively by the one or more processors, the base station causes the initial CS in the second CS allocation method to be allocated at a distance of offset (CS_dist / 2) from the allocation location of the initial CS in the first CS allocation method, and the CS_dist may be the interval between adjacent CSs during PUCCH resource allocation.

[0018] In one embodiment, when the above commands are executed individually or collectively by the one or more processors, the base station may further use the first CS allocation method when the terminal index of each terminal allocated the PUCCH resource is less than or equal to NOS*(12 / CS_dist), and use the second CS allocation method when the terminal index of each terminal allocated the PUCCH resource is greater than NOS*(12 / CS_dist), and first perform the first CS allocation method for a first number of terminals among the terminals, and then perform the second CS allocation method for the remaining second number of terminals excluding the first number of terminals among the terminals, wherein NOS is the length of an orthogonal sequence (OS) and CS_dist may be the interval between adjacent CSs during PUCCH resource allocation.

[0019] In one embodiment, when the above commands are executed individually or collectively by the one or more processors, the base station may further cause the base station to correct the CS allocation location based on the OS length and the CS length, and to perform a modulo operation such that the corrected CS allocation location is within the range of CS indices.

[0020] According to an embodiment of the present disclosure, a method performed by a base station for allocating PUCCH resources in a wireless communication system may include the step of identifying indices of said terminals corresponding to the number of terminals for allocating PUCCH resources of a first format. The method may include the step of selecting a CS for each terminal using a CS allocation method determined based on an orthogonal sequence (OS) length, a circular shift (CS) distance, and a terminal index of each terminal to be allocated PUCCH resources. The method may include the step of selecting an OS for each terminal based on the OS length and the terminal index to be allocated PUCCH resources. The method may include the step of allocating PUCCH resources of the first format to each terminal based on the selected CS and the selected OS.

[0021] In one embodiment, the PUCCH resources of the first format are multiplexed for the terminals within a single resource block (RB).

[0022] In one embodiment, the method may further include the process of transmitting to each terminal setting information including information about the selected CS and information about the selected OS for each terminal.

[0023] In one embodiment, the method may further include the process of receiving PUCCH signals from the first format-based multiplexed PUCCH resources allocated to the terminals based on the setting information.

[0024] In one embodiment, the CS distance may be determined based on the number of terminals allocated PUCCH resources and the OS length.

[0025] In one embodiment, according to the CS allocation method determined above, CS allocation to each terminal is started while maintaining the CS interval within the OS by the CS distance, and CS resources for each terminal can be allocated by circulating the OS by the length of the OS, which is NOS.

[0026] In one embodiment, the CS allocation method is determined as one of a first CS allocation method and a second CS allocation method based on the terminal index of each terminal, and the second CS allocation method may perform CS allocation between the CSs that were first allocated by the first CS allocation method.

[0027] In one embodiment, in the second CS allocation method, the initial CS may be allocated at a distance of offset (CS_dist / 2) from the allocation location of the initial CS in the first CS allocation method, and the CS_dist is the distance between adjacent CSs when PUCCH resource allocation.

[0028] In one embodiment, the first CS allocation method is used when the terminal index of each terminal allocated the PUCCH resource is less than or equal to NOS*(12 / CS_dist), and the second CS allocation method is used when the terminal index of each terminal allocated the PUCCH resource is greater than NOS*(12 / CS_dist); the first CS allocation method is performed first for a first number of terminals among the terminals, and the second CS allocation method is performed for the remaining second number of terminals excluding the first number of terminals among the terminals, and NOS is the OS length, and CS_dist may be the interval between adjacent CSs when allocating the PUCCH resource.

[0029] In one embodiment, the process of selecting the CS in the method may further include a process of correcting the CS allocation location based on the OS length and the CS length, and a process of performing a modulo operation such that the corrected CS allocation location is within the range of CS indices.

[0030] According to an embodiment of the present disclosure, in a storage medium storing at least one computer-readable instruction, the at least one instruction causes the base station to perform at least one operation when executed individually or collectively by one or more processors including processing circuitry, and the at least one operation may include an operation of identifying indices of said terminals corresponding to the number of terminals (UEs) for the allocation of PUCCH resources of a first format. In one embodiment, the at least one operation may include an operation of selecting a CS for each terminal using a CS allocation method determined based on an orthogonal sequence (OS) length, a circular shift (CS) distance, and a terminal index of each terminal to be allocated PUCCH resources. In one embodiment, the at least one operation may include an operation of selecting an OS for each terminal based on the OS length and the terminal index to be allocated PUCCH resources. In one embodiment, the at least one operation may include an operation of allocating PUCCH resources of the first format to each terminal based on the selected CS and the selected OS.

[0031] FIG. 1 is a diagram showing an example of the basic structure of time-frequency resources of a 5G system.

[0032] FIG. 2 is a diagram showing an example of a frame, subframe, and slot structure of a 5G system.

[0033] FIG. 3 is a diagram showing an example of a bandwidth portion setting in a 5G system.

[0034] FIG. 4 is a diagram showing an example of a control resource set setting of a PDCCH in a 5G system.

[0035] FIG. 5 is a diagram illustrating an example of multiplexed transmission of multiple terminals using PUCCH format 1 in a wireless communication system.

[0036] FIG. 6 is a flowchart illustrating an example of a CS allocation method for multiplexed PUCCH resource allocation based on PUCCH format 1 in a wireless communication system according to an embodiment of the present disclosure.

[0037] FIG. 7 is a flowchart illustrating an example of an OS allocation method for multiplexed PUCCH resource allocation based on PUCCH format 1 in a wireless communication system according to an embodiment of the present disclosure.

[0038] FIG. 8 is a flowchart illustrating an example of a multiplexed PUCCH allocation method based on PUCCH format 1 in a wireless communication system according to an embodiment of the present disclosure.

[0039] FIG. 9 is a drawing showing an example of the configuration of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0040] The operating principles of the present disclosure will be described in detail below with reference to the attached drawings. In describing the present disclosure below, specific descriptions of related known functions or configurations will be omitted if it is determined that such detailed descriptions would unnecessarily obscure the essence of the present disclosure. Furthermore, the terms described below are defined in consideration of their functions in the present disclosure, and these may vary depending on the intentions or practices of the user or operator. Therefore, their definitions should be based on the content throughout this specification.

[0041] The advantages and features of the present disclosure and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure is complete and to fully inform those skilled in the art of the scope of the invention, and the present disclosure is defined only by the scope of the claims. Throughout the specification, like reference numerals refer to like components.

[0042] At this point, it will be understood that each block of the process flow diagrams and combinations of the flow diagrams can be executed by computer program instructions.

[0043] Additionally, each block may represent a module, segment, or part of code containing one or more executable instructions for executing a specified logical function(s). It should also be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For instance, two blocks described in succession may actually be executed substantially simultaneously, or the blocks may be executed in reverse order according to their corresponding functions.

[0044] In this embodiment, the term "part" refers to a software or hardware component such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit), and the "part" performs certain roles. However, the meaning of "part" is not limited to software or hardware. The "part" may be configured to reside in an addressable storage medium or configured to run one or more processors. Thus, as an example, the "part" includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and "parts" may be combined into a smaller number of components and "parts" or further separated into additional components and "parts." In addition, the components and 'parts' may be implemented to utilize one or more CPUs within the device or secure multimedia card. Also, in the embodiments, 'parts' may include one or more processors.

[0045] In the present disclosure, each of the phrases such as “A / B”, “A or B”, “A and / or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof. Terms such as “first”, “second”, or “first” or “second” may be used simply to distinguish a component from another component and do not limit the components in any other aspect (e.g., importance or order).

[0046] In the present disclosure, a base station (BS) is a network entity capable of performing resource allocation for a terminal and communicating with the terminal through a wireless network, and may be at least one of an eNode B, Node B, gNB, RAN (Radio Access Network), AN (Access Network), RAN node, IAB (Integrated Access / Backhaul) node, wireless access unit, base station controller, a node on a network, or a TRP (transmission reception point). A terminal (UE) may be at least one of a terminal, MS (Mobile Station), cellular phone, smartphone, computer, or a multimedia system capable of performing communication functions.

[0047] For convenience of explanation below, some terms and names defined in the 3GPP NR standard may be used. However, the present invention is not limited by the above terms and names and can be applied in the same way to systems conforming to other standards.

[0048] Figure 1 is a diagram showing an example of the basic structure of time-frequency resources of a 5G system.

[0049] Referring to FIG. 1, the horizontal axis in FIG. 1 represents the time domain, and the vertical axis represents the frequency domain. In the time and frequency domains, the basic unit of a resource is a resource element (RE) (101), which can be defined as one OFDM (Orthogonal Frequency Division Multiplexing) symbol (102) on the time axis and one subcarrier (103) on the frequency axis. In the frequency domain For example, 12 consecutive REs can form a single resource block (RB) (104). In one embodiment, multiple OFDM symbols can form a single subframe (110). In FIG. 1 is the number of OFDM symbols per subframe (110) for setting the subcarrier spacing (μ), and for a more specific description of the resource structure in a 5G system, refer to the TS 38.211 section 4 specification.

[0050] The above RE (101) can be represented as an OFDM symbol index and a subcarrier index. The above RB (104) (or Physical Resource Block, PRB) is in the frequency domain. It can be defined as n consecutive subcarriers. In a 5G system = 12, and the data rate can increase in proportion to the number of RBs scheduled to the terminal. In a wireless communication system, the base station maps data in units of RBs and can generally perform scheduling for RBs that constitute one slot for the terminal. That is, in a 5G system, the basic time unit for scheduling is a slot, and the basic frequency unit for scheduling can be an RB.

[0051] Figure 2 is a diagram showing an example of the frame, subframe, and slot structure of a 5G system.

[0052] Referring to FIG. 2, one frame (Frame, 200) is composed of one or more subframes (Subframe, 201), and one subframe may be composed of one or more slots (Slot, 202). For example, one frame (200) may be defined as 10ms. One subframe (201) may be defined as 1ms, in which case one frame (2-00) may be composed of a total of 10 subframes (201). One slot (202, 203) may be defined as 14 OFDM symbols (i.e., the number of symbols per slot ( )=14). One subframe (201) may be composed of one or more slots (2-02, 2-03), and the number of slots (202, 203) per one subframe (201) may vary depending on the setting value μ (204, 205) for the subcarrier spacing. In the example of FIG. 2, cases where μ=0 (204) and μ=1 (205) are shown as the subcarrier spacing setting value are illustrated. For example, when μ=0 (204), one subframe (201) may be composed of one slot (202), and when μ=1 (205), one subframe (201) may be composed of two slots (203). That is, the number of slots per one subframe ( ) may vary, and accordingly, the number of slots per frame ( ) can change.

[0053] Figure 3 is a diagram showing an example of a bandwidth portion setting in a 5G system.

[0054] The Bandwidth Part (BWP) setting in a 5G communication system will be explained in detail with reference to the drawing.

[0055] FIG. 3 shows an example in which the terminal bandwidth (UE bandwidth) (300) is configured into two bandwidth parts, namely Bandwidth Part #1 (BWP#1) (301) and Bandwidth Part #2 (BWP#2) (302). The base station may configure one or more BWPs for the terminal and may configure the following information for each BWP. For example, "locationAndBandwidth" indicates the location and bandwidth in the frequency domain of the BWP, "subcarrierSpacing" indicates the subcarrier spacing to be used in the BWP, and "cyclicPrefix" indicates whether an extended CP (cyclic prefix) is used for the BWP.

[0056] In a 5G system, the base station can set up, for example, four DL BWPs for the terminal and activate one of the four DL BWPs. Additionally, the base station can set up, for example, four UL BWPs for the terminal and activate one of the four UL BWPs.

[0057] Of course, the above examples are not limited, and various parameters related to the BWP may be configured for the terminal in addition to the above configuration information. The above information may be transmitted by the base station to the terminal via higher-layer signaling, for example, Radio Resource Control (RRC) signaling. At least one of the configured BWPs may be activated. Whether a configured BWP is activated may be transmitted semi-statically from the base station to the terminal via RRC signaling or dynamically via Downlink Control Information (DCI).

[0058] According to some embodiments, prior to the Radio Resource Control (RRC) connection, the terminal may receive an Initial Bandwidth Part (Initial BWP) for initial connection from the base station via a Master Information Block (MIB). More specifically, during the initial connection phase, the terminal may receive configuration information for a Control Resource Set (CORESET) and a Search Space via the MIB, through which a PDCCH can be transmitted to receive system information required for initial connection (which may correspond to Remaining System Information (RMSI) or System Information Block 1 (SIB1)). The Control Resource Set and Search Space configured via the MIB may each be considered as Identity (ID) 0. The Control Resource Set and Search Space configured via the MIB may be referred to as a Common Control Resource Set and a Common Search Space, respectively. The base station may notify the terminal via the MIB of configuration information, such as frequency allocation information, time allocation information, and numerology, for Control Area #0. In addition, the base station may notify the terminal via the MIB of configuration information regarding the monitoring period and occasion for control region #0, that is, configuration information regarding search region #0. The terminal may regard the frequency region set as control resource set #0 obtained from the MIB as the initial bandwidth portion for initial access. At this time, the identifier (ID) of the initial bandwidth portion may be considered as 0. The above control resource set may be referred to as a control region, a control resource region, etc.

[0059] The settings for the BWP supported by the above 5G can be used for various purposes.

[0060] According to some embodiments, if the bandwidth supported by the terminal is smaller than the system bandwidth, this can be supported through the BWP setting. For example, by setting the frequency location of the BWP to the terminal, the terminal can transmit and receive data at a specific frequency location within the system bandwidth.

[0061] Additionally, according to some embodiments, a base station may set multiple BWPs for a terminal for the purpose of supporting different numerologies. For example, to support data transmission and reception using both a 15 kHz subcarrier interval and a 30 kHz subcarrier interval for a terminal, two bandwidth portions may be set to subcarrier intervals of 15 kHz and 30 kHz, respectively. Different bandwidth portions may be frequency division multiplexed, and when data transmission and reception is to be performed with a specific subcarrier interval, the BWP set for that subcarrier interval may be activated.

[0062] In a 5G system, scheduling information for uplink data (or PUSCH) or downlink data (or PDSCH) is included in the DCI and transmitted from the base station to the terminal. The terminal can monitor the fallback DCI format and the non-fallback DCI format for the PUSCH or PDSCH. The fallback DCI format may consist of fixed fields predefined between the base station and the terminal, and the non-fallback DCI format may include configurable fields.

[0063] DCI can be transmitted via the PDCCH, a physical downlink control channel, after undergoing channel coding and modulation processes. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC can be scrambled into a Radio Network Temporary Identifier (RNTI) corresponding to the terminal's identity. Different RNTIs may be used depending on the purpose of the DCI message, such as UE-specific data transmission, power control commands, or random access responses. In other words, the RNTI is not transmitted explicitly but is included in the CRC calculation process. Upon receiving a DCI message transmitted over the PDCCH, the terminal checks the CRC using its assigned RNTI; if the CRC check result is correct, the terminal knows that the message was sent to it.

[0064] Figure 4 is a diagram showing an example of a control resource set setting of a PDCCH in a 5G system.

[0065] FIG. 4 illustrates an example of a Control Resource Set (CORESET) in which a PDCCH is transmitted in a 5G system. FIG. 4 illustrates an example in which two Control Resource Sets (Control Resource Set #1 (401), Control Resource Set #2 (402)) are set within a bandwidth part (BWP) (410) of a terminal in the frequency axis and within one slot (420) in the time axis. The Control Resource Sets (401, 402) can be set to a specific frequency resource (403) within the entire terminal bandwidth part (410) in the frequency axis. In the time axis, they can be set to one or multiple OFDM symbols and can be defined as the Control Resource Set Duration (404). Referring to the example illustrated in FIG. 4, Control Resource Set #1 (401) is set to a Control Resource Set Duration of 2 symbols, and Control Resource Set #2 (402) is set to a Control Resource Set Duration of 1 symbol. In a 5G system, a control resource set can be configured by a base station to a terminal through upper layer signaling (e.g., System Information, MIB, RRC signaling). Configuring a control resource set to a terminal means providing information such as the control resource set identifier, the frequency location of the control resource set, and the symbol length of the control resource set.

[0066] In the present disclosure, upper layer signaling information may be signaling information corresponding to at least one or a combination of one or more of the following signaling information.

[0067] - MIB (Master Information Block)

[0068] - SIB (System Information Block) or SIB

[0069] - RRC (Radio Resource Control) Information

[0070] - MAC (Medium Access Control) CE (Control Element)

[0071] Additionally, L1 signaling information may be signaling information corresponding to at least one or a combination of at least one of the following physical layer channels or signaling methods using signaling.

[0072] - PDCCH (Physical Downlink Control Channel)

[0073] - DCI (Downlink Control Information)

[0074] - Terminal-specific (UE-specific) DCI

[0075] - Group common DCI

[0076] - Common DCI

[0077] In addition, in the embodiments of the present disclosure below, information transmitted and received between a base station and a terminal by upper layer signaling information may also be transmitted and received by various combinations of upper layer signaling information and / or L1 signaling information.

[0078] This disclosure relates to a resource allocation method for PUCCH. To aid in understanding this disclosure, we will describe the PUCCH format and resource allocation method in a 3GPP-based 5G system (i.e., an NR system).

[0079] In 5G systems, various PUCCH formats defined in NR standards can be used depending on the length and type of control information transmitted via PUCCH. In 5G systems, the PUCCH structure has been improved compared to 4G systems (i.e., LTE systems), enabling more efficient transmission of control information. [Table 1] below summarizes the characteristics of the five PUCCH formats defined in NR standards.

[0080] [Table 1]

[0081]

[0082] Referring to [Table 1] above, the five PUCCH formats are classified into PUCCH format 1 to PUCCH format 4. Additionally, PUCCH can be classified into short PUCCH format and long PUCCH format depending on its length. The short PUCCH format includes PUCCH format 0 and PUCCH format 2, and uses one or two OFDM (orthogonal frequency division multiplexing) symbols; PUCCH format 0 uses one RB, and PUCCH format 2 can use one to sixteen RB(s). The long PUCCH format includes PUCCH format 1, PUCCH format 3, and PUCCH format 4, and can use four to fourteen OFDM. PUCCH Format 1 and PUCCH Format 4 use one RB, and PUCCH Format 3 can use one or more RBs (e.g., up to 12). Long PUCCH formats can provide sufficient transmission power for a relatively long period of time, so coverage (reception area) can be increased compared to short PUCCH formats. PUCCH Format 3 enables PUCCH transmission using multiple RBs, similar to PUCCH Format 2, and can transmit a large amount of UCI bits at once. PUCCH Format 0, PUCCH Format 1, and PUCCH Format 4 can use only one RB to transmit UCI.

[0083] The present disclosure will primarily describe a method for allocating resources in PUCCH format 1. However, it should be noted that the PUCCH resource allocation method of the present disclosure is not limited to PUCCH format 1. The PUCCH resource allocation method of the present disclosure described below can be applied in the same or similar manner when allocating PUCCH resources while reducing interference effects between multiple terminals using one or more RB(s).

[0084] PUCCH Format 1 is used to transmit UCI of 2 bits or less, like PUCCH Format 0, but unlike PUCCH Format 0 which uses a short PUCCH format, it uses a long PUCCH format. PUCCH Format 1 uses only one RB in the frequency domain, but the data symbol used to transmit the UCI and the reference signal symbol for coherent reception are separated from each other. The modulation method for PUCCH Format 1 uses BPSK (binary phase-shift keying) when transmitting 1 bit of information, and QPSK (quadrature phase-shift keying) when transmitting 2 bits of information. In PUCCH Format 1, information bits modulated by BPSK or QPSK for transmission may be multiplied by a low PAPR (peak-to-average power ratio) sequence of, for example, length 12, used in PUCCH Format 0. The above sequence of length 12 can be an orthogonal sequence such as the Walsh-Hadamard sequence, for example.

[0085] When allocating PUCCH resources to multiple terminals within a single RB, such as in PUCCH Format 1, PUCCH resources can be efficiently allocated using orthogonal sequences and cyclic shifts to reduce interference between terminals. A PUCCH resource allocation method that utilizes both orthogonal sequences and cyclic shifts enables, for example, multiple terminals to transmit UCIs simultaneously within the same resource (a single RB). For instance, if different orthogonal sequences are allocated to multiple terminals using PUCCH Format 1 for UCI transmission, mutual interference between the orthogonal sequences is reduced, thereby mitigating interference between terminals within the same RB. Furthermore, since the number of different orthogonal sequences that can be allocated to multiple terminals within the same RB is limited, there may be terminals using the same orthogonal sequence within the same RB. Interference between terminals using the same orthogonal sequence can be mitigated by using cyclic shifts. A base station can allocate PUCCH resources to multiple terminals for transmitting UCIs within the same RB using PUCCH Format 1.

[0086] The base station can provide information on the orthogonal sequence assigned to each terminal performing PUCCH transmission based on PUCCH Format 1 and information on the circular shift using upper layer signaling information and / or L1 signaling information.

[0087] Specifically, when a dedicated PUCCH resource is configured for a terminal, the terminal may receive configuration information for one or more PUCCH resources through upper-layer signaling, such as RRC information, for example. When the PUCCH format is PUCCH format 1, the configuration information may be provided as shown in the example in [Table 2] below.

[0088] [Table 2]

[0089]

[0090] In [Table 2] above, the "initialCyclicShift" information represents the index for the initial cyclic shift and corresponds to the information regarding the cyclic shift. The "timeDomainOCC" information represents the index for the orthogonal cover code and corresponds to the information regarding the orthogonal sequence. Also, in [Table 2] above, the "nrofSymbols" information represents the number of symbols in the PUCCH transmission, and the "startingSymbolIndex" information represents the starting symbol of the PUCCH transmission.

[0091] FIG. 5 is a diagram illustrating an example of multiplexed transmission of multiple terminals using PUCCH format 1 in a wireless communication system. FIG. 5 assumes a case where multiple terminals transmit a UCI in PUCCH format 1 using 8 OFDM symbols. In the example of FIG. 5, among the 8 OFDM symbols (501, …, 508), 4 OFDM symbols (502, 504, 506, 508) can be used to carry data symbols corresponding to the UCI sequence, and the remaining 4 OFDM symbols (501, 503, 505, 507) can be used to carry RS symbols corresponding to the reference signal (RS). The number of RS symbols can be determined according to the total number of symbols. Figure 5 briefly illustrates an example of mapping four symbols in a symbol mapping for transmission of PUCCH format 1 on the right, in a resource of 1 slot containing 12 REs in the frequency domain and 1 RB containing 14 symbols in the time domain.

[0092] Referring to FIG. 5, in PUCCH format 1, a UCI sequence (511) of length 12, modulated via BPSK / QPSK (510), can be mapped to data symbols in block units by multiplying by an orthogonal sequence (512) assigned to each terminal and passing through an Inverse Fourier Transform (IFFT) (513). The length of the orthogonal sequence is equal to the number of symbols carrying the UCI. Using an orthogonal sequence in the time domain for PUCCH transmission based on PUCCH format 1 is because it allows multiple terminals to use the same base sequence and phase while increasing multiplexing capacity. In PUCCH format 1, the base sequence can be, for example, a Zadoff-Chu sequence. Referring to FIG. 5, an unmodulated RS sequence of length 12 (521) can be mapped to RS symbols by multiplying by an orthogonal sequence (522) assigned to each terminal in block units and passing through an IFFT (523). Here, the RS can use the demodulation-reference signal (DM-RS) for the demodulation of the UCI. An orthogonal sequence can be used to match the shorter length between the UCI data and the RS, and the example in FIG. 5 illustrates the case where a sequence of length 2 is used as the orthogonal sequence. In this case, by applying 12 cyclic shifts to the 2 orthogonal sequences and the base sequence, PUCCH transmissions of a total of 24 terminals within the same time-frequency resource (e.g., one RB) can be multiplexed. The number of terminals capable of transmitting PUCCH format 1 within one RB can be determined within the range of the product of the number of orthogonal sequences and the number of cyclic shifts.

[0093] For multiplexed PUCCH transmission based on PUCCH Format 1 by multiple terminals, the base station can provide each terminal with information regarding the orthogonal sequence (OS) and the circular shift (CS) through upper-layer signaling. In other words, for multiplexed PUCCH transmission based on PUCCH Format 1, the base station can assign different combinations of the orthogonal sequence (OS) and the circular shift (CS) to each terminal multiplexed within the same RB. If the combinations of the orthogonal sequence (OS) and the circular shift (CS) are different, the PUCCH signals of each terminal within the same RB will have orthogonal characteristics to one another, thereby mitigating mutual interference between the PUCCH signals of the terminals.

[0094] However, in an actual communication environment, even if a base station assigns different combinations of orthogonal sequence (OS) and circular shift (CS) to multiple terminals, when the base station receives multiplexed PUCCH signals based on PUCCH Format 1, time offsets and frequency offsets exist between the PUCCH signals, so orthogonality cannot be guaranteed between terminals using different combinations of OS and CS, and interference may occur between the terminals' PUCCH signals. The above time offset and frequency offset have different ways of affecting interference between terminals. In the case of a time offset, it can make a CS that is orthogonal in the frequency domain non-orthogonal, and in the case of a frequency offset, it can make an OS that is orthogonal in the time domain non-orthogonal. Such mutual interference is one of the causes of reduced PUCCH reception SINR (signal to interference and noise ratio), and if the interference effect due to time offset and frequency offset is significant, the SINR becomes saturated, making it impossible for the base station to accurately receive multiplexed PUCCH signals due to mutual interference, even if terminals transmit PUCCH signals at high transmission power.

[0095] The process of receiving multiplexed PUCCH signals based on PUCCH Format 1 from multiple terminals at a base station is explained with reference to the mathematical equations as shown in the example below.

[0096] Among the multiplexed PUCCH signals based on PUCCH Format 1 within a single RB Transmitted signal at the i-th tone and k-th symbol of the i-th terminal This can be expressed as shown in the following [Equation 1]. In OFDM, a tone can correspond to a subcarrier in the frequency domain. Here and each It refers to the Circular Shift (CS) and Orthogonal Sequence (OS) assigned to the i-th terminal from the base station via upper-layer signaling.

[0097] [Mathematical Formula 1]

[0098]

[0099] For example, among the multiplexed PUCCH signals based on PUCCH Format 1 within a single RB, 2 terminals (terminal and terminal Assuming the PUCCH signals of ) are multiplexed, terminal and terminal Received signal from the base station at the j-th tone and k-th symbol can be expressed as follows [Mathematical Equation 2]. At this time each terminal It refers to the time offset and frequency offset of, each terminal It refers to the time offset and frequency offset. (Assuming an AWGN (Additive White Gaussian Noise) channel)

[0100] [Mathematical Formula 2]

[0101]

[0102] terminal The base station's received signal at the i-th tone and k-th symbol with CS and OS removed, based on It is equal to the following [Equation 3].

[0103] [Mathematical Formula 3]

[0104]

[0105] When accumulating 12 tones in the frequency domain for demultiplexing the multiplexed PUCCH signals received from the base station, it is as follows [Equation 4].

[0106] [Mathematical Formula 4]

[0107]

[0108] When K symbols are accumulated in the time domain for demultiplexing of multiplexed PUCCH signals received from a base station, it is as follows [Equation 5].

[0109] [Mathematical Formula 5]

[0110]

[0111] In the above [Mathematical Formula 5], the terminal Terminal acting as an interference to the PUCCH signal If there is no time offset or frequency offset of the PUCCH signal, the terminal as shown in [Equation 6] below Since the PUCCH signal becomes 0, there is no mutual interference.

[0112] [Mathematical Formula 6]

[0113]

[0114] However, the terminal If a time offset and a frequency offset exist for the PUCCH signal, the terminal Since the PUCCH signal does not become 0, the terminal It acts as interference to the PUCCH signal. Due to the influence of mutual interference, phase changes in the PUCCH signal and interference between CSs may occur due to the time offset, while inter-symbol interference and OS interference may occur due to the frequency offset. In other words, time offset and frequency offset can affect interference between CSs and between OSs.

[0115] Interference between CSs due to time offset in PUCCH signals is terminal , It can be seen that the amount of interference is controlled by the CS interval of the PUCCH signals, and that interference is reduced when the CS interval is large. Even in interference between OSs caused by frequency offset, the terminal , The amount of interference is controlled by the OS interval of the PUCCH signals, and if the OS interval is large, the interference can be reduced.

[0116] Table 3 below shows an example of allocating different combinations of orthogonal sequences (OS) and circular shifts (CS) to each multiplexed terminal within the same RB for multiplexed PUCCH resource allocation based on PUCCH format 1. It shows an example of allocating different combinations of orthogonal sequences (OS) and circular shifts (CS) to 18 terminals (Nue = 18) when the length / number of orthogonal sequences (OS) (NOS = 3) is 3 with indices 0, 1, and 2, and the number of circular shifts (CS) is 12 with indices 0 to 11.

[0117] [Table 3]

[0118]

[0119] As in the example in [Table 3] above, an example of arranging / mapping PUCCH resources allocated to 18 terminals (Nue=18) according to different combinations of orthogonal sequence (OS) and circular shift (CS) on the horizontal axis in terms of orthogonal sequence (OS) index and arranging / mapping them on the vertical axis in terms of circular shift (CS) index is shown in [Table 4] below. In [Table 4], the indices for UE0 to UE17 are assigned according to the allocation order of PUCCH resources.

[0120] [Table 4]

[0121]

[0122] In [Table 4] above, the PUCCH resources for UE0 to UE17 are allocated sequentially for each index of the Orthogonal Sequence (OS) in the order of increasing Circular Shift (CS) index from top to bottom. In [Table 4], it can be seen that the PUCCH resources of each UE are allocated with a spacing / distance of 2 on the vertical axis (CS) and horizontal axis (OS), respectively, relative to the PUCCH resources of adjacent UEs. The closer the spacing / distance between CSs on the vertical axis (CS) between adjacent UEs, the greater the interference effect due to time offset, and the closer the spacing / distance between OSs on the horizontal axis (OS), the greater the interference effect due to frequency offset.

[0123] Tables 5a to 5d below show examples of allocating different combinations of orthogonal sequences (OS) and circular shifts (CS) in the manner of allocating different combinations of orthogonal sequences (OS) and circular shifts (CS) in Table 3 above for multiplexed PUCCH resource allocation based on PUCCH format 1, for example, when the number / length (NOS) of the orthogonal sequence (OS) is 3 and different combinations of orthogonal sequences (OS) and circular shifts (CS) are allocated with a predetermined allocation / mapping pattern for 4, 8, 18, and 12 terminals (Nue = 4, 8, 18, 12).

[0124] [Table 5a]

[0125]

[0126] [Table 5b]

[0127]

[0128] [Table 5c]

[0129]

[0130] [Table 5d]

[0131]

[0132] Referring to [Table 5a] through [Table 5d] above, it can be seen that the allocation positions of the orthogonal sequence (OS) and circular shift (CS) for "UE1" change in each case of [Table 5a] through [Table 5d]. This means that the allocation method of the combination of the orthogonal sequence (OS) and circular shift (CS) changes depending on the increase or decrease in the number (Nue) of terminals allocated PUCCH resources, and that RRC connection setup must be performed according to a predetermined allocation / mapping pattern in each case. In other words, since the number (Nue) of terminals allocated PUCCH resources is determined during the RRC connection setup stage, it means that if there is a change in the allocation method of the orthogonal sequence (OS) and circular shift (CS) due to the increase or decrease in the number (Nue) of terminals, the RRC connection setup for those terminals must also be performed again.

[0133] Therefore, as a standardized method for multiplexed PUCCH resource allocation based on PUCCH Format 1, an optimal PUCCH resource allocation method is required that can accommodate the maximum number of terminals (Nue) allocated PUCCH resources while efficiently reducing interference effects, without performing new RRC connection settings according to the increase or decrease in the number (Nue) of terminals allocated PUCCH resources.

[0134] Table 6 below shows an example of allocating PUCCH resources for the 18 terminals, UE0 to UE17, in Table 4, by sequentially allocating them from top to bottom (i.e., in the direction of the arrows in Table 6) for each OS index of an orthogonal sequence (OS), starting from a designated starting CS index in each OS index and proceeding in an increasing order of cyclic shift (CS) indices, and subsequently filling in any empty CS index(s) prior to that designated starting CS index. In Table 6, UE0 to UE17 can be understood as the order in which PUCCH resources based on PUCCH Format 1 are allocated to the corresponding terminals. For example, PUCCH resources may be allocated in ascending order starting from UE0. Additionally, in Table 6, UE0 to UE17 can be understood as the indices of terminals receiving PUCCH resources based on PUCCH Format 1 sequentially.

[0135] [Table 6]

[0136]

[0137] As shown in [Table 6] above, the PUCCH resources for each UE are allocated at a distance of 2 along the vertical axis (CS) and horizontal axis (OS) relative to the PUCCH resources of the immediately adjacent UE. If we assume that the maximum number of terminals eligible for PUCCH resources based on PUCCH Format 1 within a single RB is 18, considering interference effects, then the PUCCH resource allocation method in [Table 6] may at least account for interference effects. However, in a communication system, the number of terminals allocated PUCCH resources cannot remain the same with every allocation and may increase or decrease. For instance, let's assume that while the maximum number of terminals eligible for PUCCH resources based on PUCCH Format 1 within a single RB is 18, the actual number of terminals allocated resources at any given time is 9. In other words, while the maximum number of terminals eligible for PUCCH resource allocation in an actual communication environment may be predetermined, maximum allocation is not required at every moment.

[0138] Table 7 below assumes that PUCCH resources based on PUCCH Format 1 are allocated within a single RB in the same manner as Table 6 above, but that the number of terminals receiving PUCCH resources at that time is 9. Referring to the allocation example in Table 7, it can be seen that the PUCCH resources allocated to the 9 terminals, UE0 to UE9, are not distributed with spacing / distance to reduce interference effects within the RB, but are allocated while maintaining CS spacing 2 on one side of the RB. Therefore, in the case of Table 7, although the interference effects of PUCCH signals between the 9 terminals could be further reduced, optimal resource allocation cannot be performed.

[0139] [Table 7]

[0140]

[0141] The present disclosure proposes a method for multiplexed PUCCH resource allocation based on PUCCH Format 1, wherein orthogonal sequences (OS) and circular shifts (CS) are allocated to terminals at optimal distances without performing new RRC connection settings as the number of terminals allocated PUCCH resources increases or decreases. According to this disclosure, PUCCH resources can be adaptively distributed as the number of terminals allocated PUCCH resources increases or decreases, thereby efficiently reducing the mutual interference effects caused by OS and CS.

[0142] FIG. 6 is a flowchart illustrating an example of a CS allocation method for multiplexed PUCCH resource allocation based on PUCCH format 1 in a wireless communication system according to an embodiment of the present disclosure. The method of FIG. 6 can be performed by a base station that allocates CS resources to a plurality of terminals within an RB.

[0143] The method of Fig. 6 is proposed to improve the reception performance of PUCCH by allocating CSs to multiple terminals to reduce interference effects caused by frequency offset, for PUCCH resource allocation based on PUCCH format 1 in a wireless communication system, by starting the allocation while maintaining a fixed CS distance within the same OS.

[0144] Referring to Fig. 6, in process 601, the base station confirms that the configurable range of the cyclic shift (CS) has a total of 12 CS indices from 0 to 11, as exemplified in the "initialCyclicShift" information of [Table 2].

[0145] In the 602 process, the base station identifies the indices of terminals corresponding to the number of terminals for multiplexed PUCCH resource allocation based on PUCCH Format 1 within the same RB (e.g., within one RB). For example, if the total number of terminals capable of PUCCH resource allocation based on PUCCH Format 1 within one RB is 18 and the number of terminals to be allocated PUCCH resources is 18, the terminal indices corresponding to the number of terminals to be allocated PUCCH resources (Nue) can be set / assigned as UE0 to UE17 as shown in the example in [Table 8] below.

[0146] The above terminal indices can be set / assigned in the order in which PUCCH resources are allocated. In addition, during the above 602 process, the base station checks for each terminal to be allocated PUCCH resources whether the corresponding terminal index (ue_index) satisfies [Equation 7] below.

[0147] [Mathematical Formula 7]

[0148]

[0149] In the above [Equation 7], the terminal index (ue_index) indicates which terminal is allocated the PUCCH resource, and the CS distance (CS_dist) indicates the CS interval within the same orthogonal sequence (OS). In the present disclosure, the CS distance (CS_dist) can be expressed as shown in the following [Equation 8].

[0150] [Mathematical Formula 8]

[0151]

[0152] In the above [Equation 8], the Ceil function calculates the maximum integer less than or equal to a real number, and the Floor function calculates the minimum integer greater than or equal to a real number. Min(A, B) is a function that outputs the minimum value between A and B. Referring to [Table 2], since the range of "timeDomainOCC" information representing the OS in the NR specification can be set within the range from 0 to 6, the value of B in the MIN function was set to 6. The value of B in the MIN function may vary depending on the range of configurable OS lengths. Nue represents the number of terminals allocated PUCCH resources, and NOS represents the length / number of orthogonal sequences (OS) allocated according to the number of RS symbols.

[0153] As shown in [Equation 8] above, in the present disclosure, the CS distance (CS_dist) can be determined based on the number of terminals (Nue) allocated PUCCH resources at that time and the orthogonal sequence length (NOS). In [Equation 8], the CS distance (CS_dist) can be set to the value of Floor(12 / Ceil(Nue / NOS)*2, for example, when the value of Floor(12 / Ceil(Nue / NOS)*2 is less than 6. The reason for multiplying the Floor function by 2 here is to ensure that when allocating PUCCH resources to the maximum number of terminals within a single RB, the spacing between adjacent CSs of the maximum number of terminals to which PUCCH resources are allocated is at least Floor(12 / Ceil(Nue / NOS)), and to allocate PUCCH resources by maximizing the CS spacing of the terminals at the beginning of PUCCH resource allocation (e.g., widening the CS spacing by a multiple of 2 in [Equation 8]). As an optional embodiment, the multiplier multiplied to the Floor(12 / Ceil(Nue / NOS)) function may be 2 or greater.

[0154] In the above 602 process, if the CS distance (CS_dist) is determined and the terminal index (ue_index) of a terminal receiving sequential PUCCH resources does not satisfy [Equation 7], that is, if the terminal index (ue_index) is less than or equal to NOS*(12 / CS_dist), the base station may select a CS for the terminal index (ue_index) and allocate it to that terminal using the first CS allocation method according to the above 603, 604, 607, and 608 processes. The CS selection / allocation by the above first CS allocation method represents an example in which a CS is allocated such that the CS distance (CS_dist) between adjacent CSs within the same OS becomes 4, such as the CS allocation method for terminals with terminal index (ue_index) of UE0 to UE8 in [Table 8]. CS allocation for terminals of UE0 to UE8 can be performed sequentially in the direction indicated by the arrow in [Table 8].

[0155] [Table 8]

[0156]

[0157] To explain the first CS allocation method according to the above 603, 604, 607, and 608 processes, in process 603, the base station can set init_CS, which is the CS that starts the initial allocation, and CS allocation can be performed by cyclically shifting within 12 CSs within the same OS. The above init_CS can be used when a specific area in the CS needs to be emptied from the system. In process 604, when allocating CS for ue_index, the base station determines the location of CS1 for CS allocation at intervals of CS distance (CS_dist), starting from init_CS, and in process 607, corrects the CS allocation location CS1 to CS2 based on the orthogonal sequence length (NOS), and in process 608, selects / allocates the CS for ue_index by performing a modulo operation of 12 Mod (CS2, 12) so that the CS2 location does not go beyond the range of CS indices from 0 to 11. And in the above first CS allocation method, the CS allocation position CS1 and the corrected CS allocation position CS2 can be represented as follows [Equation 9].

[0158] [Mathematical Formula 9]

[0159]

[0160] Meanwhile, in the above 602 process, the CS distance (CS_dist) is determined, and if the terminal index (ue_index) of a terminal receiving sequential PUCCH resources satisfies [Equation 7], that is, if the terminal index (ue_index) is greater than NOS*(12 / CS_dist), the base station may select a CS for the terminal index (ue_index) and allocate it to that terminal using the second CS allocation method according to the 605, 606, 607, and 608 processes. The CS selection / allocation by the second CS allocation method is an example in which a CS is allocated such that the CS distance (CS_dist) between adjacent CSs becomes 4 among the remaining CSs, excluding the CSs allocated to terminals UE0 to UE8 within the same OS by the first CS allocation method, such as the CS allocation method for terminals with terminal index (ue_index) of UE9 to UE17 in [Table 8] above.

[0161] To explain the second CS allocation method according to the above 605, 606, 607, and 608 processes, in process 605, the base station can set init_CS, which is the CS that starts the initial allocation, and CS allocation can be performed by cyclically shifting within 12 CSs within the same OS. At this time, in order for CS allocation to be performed between the CSs allocated by the aforementioned first CS allocation method, in processes 605 and 606, the base station can determine the location of CS1 for CS allocation at intervals of the CS distance (CS_dist), starting from init_CS + CS_dist / 2 when allocating CS for ue_index. At this time, ue_index is corrected by 12*NOS / CS_dist so that CS allocation for terminals is performed between the CSs previously allocated by the aforementioned first CS allocation method. In process 607, the CS allocation position CS1 is corrected to CS2 based on the orthogonal sequence length (NOS), and in process 608, a modulo operation of 12 Mod (CS2, 12) is performed so that the CS2 position does not go beyond the range of CS indices from 0 to 11 (i.e., the corrected CS allocation position is within the range of CS indices) to select / assign a CS for ue_index. In the above second CS allocation method, the CS allocation position CS1 and the corrected CS allocation position CS2 can be represented as shown in [Equation 10] below.

[0162] [Mathematical Formula 10]

[0163]

[0164] In the above [Equation 10], 12 / CS_dist represents the number of terminals to which CS is allocated within one OS, and by multiplying 12 / CS_dist by NOS, CS allocation can be performed at a distance of CS distance (CS_dist) for each.

[0165] [Table 8] above shows an example of CS allocation for 18 terminals in the embodiment of FIG. 6 where the total number of terminals capable of PUCCH resource allocation based on PUCCH format 1 within one RB is 18, NOS=3, Nue=18, and init_CS=0, and [Table 9] below shows an example of CS allocation for 9 terminals in the case where the total number of terminals capable of PUCCH resource allocation is 18, NOS=3, Nue=9, and init_CS=0.

[0166] [Table 9]

[0167]

[0168] In the embodiment of FIG. 6, information regarding the selected / assigned cyclic shift (CS) for ue_index can be provided to the terminal as information of "initialCyclicShift" in [Table 2].

[0169] According to the first and second CS allocation methods in the embodiment of FIG. 6, the base station can start allocating CS to terminals while maintaining the CS interval within the same OS by the CS distance (CS_dist), and can perform CS allocation to terminals by rotating through the OS by the number of NOS that are not the same OS. Therefore, interference effects caused by short CS intervals between terminals that have been initially allocated CS can be prevented, and as a result, relative interference effects caused by frequency offset can be reduced when allocating PUCCH resources.

[0170] That is, as shown in the example in [Table 8] above, when Nue=18, the effect of relative interference caused by frequency offset can be reduced during the CS allocation process compared to the CS allocation method in [Table 6]. In addition, as shown in the example in [Table 9], when Nue=9, the CS interval increases from 2 to 4 compared to the CS allocation method in [Table 7], which not only reduces the effect of mutual interference caused by frequency offset but also allows for more efficient distribution of PUCCH resources within the RB.

[0171] FIG. 7 is a flowchart illustrating an example of an OS allocation method for multiplexed PUCCH resource allocation based on PUCCH format 1 in a wireless communication system according to an embodiment of the present disclosure. The method of FIG. 7 can be performed by a base station that allocates OS resources to multiple terminals within an RB. The OS allocation method of FIG. 7 can be performed together with the CS allocation method of FIG. 6. Referring to FIG. 7, in step 701, the base station confirms that the configurable range of the orthogonal sequence (OS) has a range of a total of 7 OS indices from 0 to 6, as exemplified in the "timeDomainOCC" information of [Table 2]. NOS represents the length / number of orthogonal sequences (OS) allocated according to the number of RS symbols, and NOS can be confirmed by the "timeDomainOCC" information. The embodiment of FIG. 6 assumes the case where NOS = 3, and in this case, since the OS can be set in the range from 0 to NOS-1, it can be set in the range of OS indices 0, 1, and 2. In the 702 process, the base station can select / assign an OS for the corresponding ue_index through the modular operation OS=Mod(ue_index, NOS).

[0172] In the above 702 process, information regarding the orthogonal sequence (OS) selected / assigned for ue_index can be provided to the terminal as the information of "timeDomainOCC" in [Table 2].

[0173] Table 10 below shows an example of pseudo-code in which the CS allocation method and OS allocation method described in the embodiments of FIGS. 6 and 7 are implemented. The pseudo-code in Table 10 can be used as an operation algorithm of a base station in the present disclosure.

[0174] [Table 10]

[0175]

[0176] A base station that performs multiplexed PUCCH resource allocation based on PUCCH format 1 using the CS allocation method and OS allocation method proposed in the embodiments of the present disclosure described above can perform efficient PUCCH resource allocation regardless of subsequent increases or decreases in the number of terminals by setting the table information applicable for CS / OS allocation according to the present disclosure once, without changing the table information for CS / OS allocation according to the increase or decrease in the number of terminals receiving PUCCH resources within the same RB. In addition, when PUCCH resource allocation is performed using the CS / OS allocation method proposed in the embodiments of the present disclosure, mutual interference can be reduced while the base station sequentially allocates CS and / or OS resources based on terminal index, which allows for the expectation of improved PUCCH reception performance and SINR at the base station.

[0177] FIG. 8 is a flowchart illustrating an example of a multiplexed PUCCH allocation method based on PUCCH format 1 in a wireless communication system according to an embodiment of the present disclosure. The method of FIG. 8 can be performed by a base station that allocates CS / OS resources to a plurality of terminals within an RB according to the methods of FIG. 6 and FIG. 7.

[0178] Referring to Fig. 8, in process 801, the base station can identify indices of terminals corresponding to the number of terminals for multiplexed PUCCH resource allocation based on PUCCH format 1.

[0179] In the 802 process, the base station can select / assign a CS for each terminal using the method of FIG. 6, based on the orthogonal sequence (OS) length, circular shift (CS) distance, and the index of each terminal to be allocated a PUCCH resource.

[0180] In the 803 process, the base station can select / assign an OS for each terminal based on the length of the orthogonal sequence (OS) and the index of each terminal to be allocated PUCCH resources, using the method of Fig. 7.

[0181] In the 804 process, the base station may transmit configuration information to each terminal, including information about the CS and OS selected / assigned for each terminal. The configuration information may be transmitted to the terminal in a manner such as [Table 2], for example.

[0182] In the 805 process, the base station allocates PUCCH resources of the first format to each terminal based on the selected / assigned CS and the selected / assigned OS in the transmitted configuration information, and can receive PUCCH signals from multiplexed PUCCH resources based on PUCCH format 1.

[0183] In one embodiment, the PUCCH resources of the first format are multiplexed for the terminals within a single resource block (RB).

[0184] In one embodiment, the method of FIG. 8 may further include the operation of a base station receiving PUCCH signals from the first format-based multiplexed PUCCH resources allocated to the terminals based on the transmitted configuration information.

[0185] In one embodiment, the CS distance may be determined based on the number of terminals allocated PUCCH resources and the OS length.

[0186] In one embodiment, according to the CS allocation method determined above, CS allocation to each terminal is started while maintaining the CS interval within the OS by the CS distance, and CS resources for each terminal can be allocated by circulating the OS by the length of the OS, which is NOS.

[0187] In one embodiment, the CS allocation method is determined as one of a first CS allocation method and a second CS allocation method based on the terminal index of each terminal, and the second CS allocation method may perform CS allocation between the CSs that were first allocated by the first CS allocation method.

[0188] In one embodiment, in the second CS allocation method, the initial CS may be allocated at a distance of an offset from the allocation location of the initial CS in the first CS allocation method. Here, the offset corresponds to CS_dist / 2 in process 605 of FIG. 6.

[0189] In one embodiment, the first CS allocation method is used when the terminal index of each terminal allocated the PUCCH resource is less than or equal to NOS*(12 / CS_dist), and the second CS allocation method is used when the terminal index of each terminal allocated the PUCCH resource is greater than NOS*(12 / CS_dist); the first CS allocation method is performed first for a first number of terminals among the terminals, and the second CS allocation method is performed for the remaining second number of terminals excluding the first number of terminals among the terminals, and NOS is the OS length, and CS_dist may be the interval between adjacent CSs when allocating the PUCCH resource.

[0190] In one embodiment, in the method of FIG. 8, the base station can correct the CS allocation location based on the OS length and the CS length, and perform a modulo operation so that the corrected CS allocation location is within the range of CS indices.

[0191] [Table 11] below shows an example of interference effects when receiving PUCCH based on PUCCH format 1 at a base station when allocating PUCCH resources using the existing CS / OS allocation method.

[0192] [Table 11]

[0193]

[0194] Table 12 below shows an example of reduced interference effects when receiving PUCCH based on PUCCH Format 1 at a base station when allocating PUCCH resources using the CS / OS allocation method according to embodiments of the present invention. For example, when a PUCCH Format 1 with a high SNR is transmitted from UE1, it can be seen that the interference effect on surrounding resources caused by the strong signal is significantly reduced compared to the existing allocation method of Table 11. Due to these technical effects, the base station can increase the PUCCH transmission power of the terminal through power control for PUCCH transmission at the terminal, thereby improving overall PUCCH reception performance.

[0195] [Table 12]

[0196]

[0197] FIG. 9 is a diagram showing an example of the configuration of a base station in a wireless communication system according to an embodiment of the present disclosure. The embodiments of FIGS. 1 to 8 can be applied to the base station of FIG. 9.

[0198] The base station of FIG. 9 may include a processor (930), a transceiver (910), and a memory (920). The processor (930), transceiver (910), and memory (920) of the base station of FIG. 9 may operate according to at least one of the methods proposed in the embodiments of FIG. 3 to 9. However, the components of the base station are not limited to the examples described above. For example, the base station may include more components or fewer components than the components described above. In addition, the processor (930), transceiver (910), and memory (920) may be implemented in the form of a single chip. The transceiver (910) is a collective term for the receiver and the transmitter of the base station and can transmit and receive signals with a terminal or another base station. At this time, the signal transmitted and received may include at least one of control information and data. To this end, the transceiver (910) may include a wired or wireless transceiver and may include various configurations for transmitting and receiving signals. The transceiver (910) may receive a signal and output it to a processor (930), and transmit the signal output from the processor (930).

[0199] Additionally, the transceiver (910) receives a communication signal and outputs it to the processor (930), and can transmit the signal output from the processor (930) to another base station through a network. The memory (920) can store programs and data necessary for the operation of a base station according to at least one of the embodiments of FIGS. 1 to 8. Additionally, the memory (920) can store control information or data included in a signal obtained from the base station. The memory (920) may be composed of a storage medium or a combination of storage media such as ROM, RAM, hard disk, CD-ROM, and DVD. Additionally, the processor (930) can control a series of processes to enable the base station to operate according to at least one of the embodiments of FIGS. 3 to 9. For example, the processor (930) may include at least one processor and can control the operation of a base station that performs multiplexed PUCCH allocation based on PUCCH format 1 according to the present disclosure.

[0200] In one embodiment, a base station in a wireless communication system comprises a transceiver (910), one or more processors (930) including a processing circuit, and a memory (920) for storing instructions. When the instructions are executed individually or collectively by the one or more processors, the base station may identify indices of the terminals corresponding to the number of terminals (UEs) for PUCCH resource allocation in a first format, select a CS for each terminal using a CS allocation method determined based on an orthogonal sequence (OS) length, a circular shift (CS) distance, and the terminal index of each terminal to be allocated a PUCCH resource, select an OS for each terminal based on the OS length and the terminal index to be allocated a PUCCH resource, and cause the PUCCH resource in the first format to be allocated to each terminal based on the selected CS and the selected OS.

[0201] In one embodiment, the PUCCH resources of the first format may be multiplexed for the terminals within a single resource block (RB).

[0202] In one embodiment, when the commands are executed individually or collectively by the one or more processors (930), the base station may further cause the base station to transmit to each terminal, via the transceiver (910), configuration information including information about the selected CS and information about the selected OS for each terminal.

[0203] In one embodiment, when the commands are executed individually or collectively by the one or more processors (930), the base station may further cause the base station to receive PUCCH signals from the first format-based multiplexed PUCCH resources allocated to the terminals based on the configuration information through the transceiver (910).

[0204] In one embodiment, when the above commands are executed individually or collectively by the one or more processors (930), the base station may be caused to determine the CS distance based on the number of terminals allocated PUCCH resources and the OS length.

[0205] In one embodiment, when the above commands are executed individually or collectively by the one or more processors (930), the base station may cause the base station to start CS allocation to each terminal by using the determined CS allocation method, maintaining the CS interval within the OS by the CS distance, and to allocate CS resources for each terminal by cycling through the OS by the length of the OS NOS.

[0206] In one embodiment, when the commands are executed individually or collectively by the one or more processors (930), the base station is configured to determine one of the first CS allocation method and the second CS allocation method as the CS allocation method based on the terminal index of each terminal, and the second CS allocation method may perform CS allocation between the CSs first allocated by the first CS allocation method.

[0207] In one embodiment, when the above commands are executed individually or collectively by one or more processors (930), the base station causes the initial CS in the second CS allocation method to be allocated at a distance of offset (CS_dist / 2) from the allocation location of the initial CS in the first CS allocation method, and the CS_dist may be the interval between adjacent CSs during PUCCH resource allocation.

[0208] In one embodiment, when the above commands are executed individually or collectively by the one or more processors (930), the base station may further use the first CS allocation method when the terminal index of each terminal allocated the PUCCH resource is less than or equal to NOS*(12 / CS_dist), use the second CS allocation method when the terminal index of each terminal allocated the PUCCH resource is greater than NOS*(12 / CS_dist), perform the first CS allocation method first for a first number of terminals among the terminals, and perform the second CS allocation method for the remaining second number of terminals excluding the first number of terminals among the terminals, wherein NOS is the length of an orthogonal sequence (OS) and CS_dist may be the interval between adjacent CSs when allocating PUCCH resources.

[0209] In one embodiment, when the above commands are executed individually or collectively by the one or more processors (930), the base station may further cause the base station to correct the CS allocation location based on the OS length and the CS length, and to perform a modulo operation such that the corrected CS allocation location is within the range of CS indices.

[0210] Methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0211] When implemented in software, a computer-readable storage medium may be provided for storing one or more programs (software modules). One or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. One or more programs include instructions that cause the electronic device to execute methods according to the embodiments described in the claims or specification of this disclosure.

[0212] Such programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, ROM (Read Only Memory), Electrically Erasable Programmable Read Only Memory (EEPROM), magnetic disc storage devices, Compact Disc-ROM (CD-ROM), Digital Versatile Discs (DVDs), or other forms of optical storage devices, magnetic cassettes. Alternatively, they may be stored in memory composed of some or all of these. Additionally, each constituent memory may include multiple units.

[0213] Additionally, the above program may be stored on an attachable storage device that can be accessed via a communication network such as the Internet, Intranet, Local Area Network (LAN), Wide LAN (WLAN), or Storage Area Network (SAN), or a combination thereof. Such a storage device may be connected to a device performing an embodiment of the present disclosure through an external port. Additionally, a separate storage device on a communication network may be connected to a device performing an embodiment of the present disclosure.

[0214] In the specific embodiments of the present disclosure described above, the components included in the invention are expressed in a singular or plural form according to the specific embodiments presented. However, the singular or plural expression is selected to suit the situation presented for convenience of explanation, and the present disclosure is not limited to singular or plural components; even if a component is expressed in the plural form, it may be composed of a singular form, or even if a component is expressed in the singular form, it may be composed of a plural form.

[0215] Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, it is understood that various modifications are possible within the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments, but should be defined by the claims set forth below as well as equivalents thereof.

Claims

1. In a base station of a wireless communication system, Transmitter / receiver (910); One or more processors (930) including processing circuitry; and The base station includes a memory (920) for storing instructions, and when the instructions are executed individually or collectively by one or more processors, Identify the indices of the terminals corresponding to the number of terminals (user equipment: UE) for the allocation of PUCCH (physical uplink control channel) resources of the first format, and Identify the indices of the terminals corresponding to the number of terminals for PUCCH resource allocation in the first format, and Select a CS for each terminal using a CS allocation method determined based on the orthogonal sequence (OS) length, cyclic shift (CS) distance, and the terminal index of each terminal to be allocated PUCCH resources, and Select an OS for each terminal based on the above OS length and the terminal index to be allocated the above PUCCH resource, and A base station that causes the allocation of PUCCH resources of the first format based on the selected CS and the selected OS for each terminal.

2. In Paragraph 1, A base station in which the PUCCH resources of the first format above are multiplexed for the terminals within a single resource block (RB).

3. In Paragraph 1 or 2, When the above commands are executed individually or collectively by the one or more processors (930), the base station, A base station that further causes each terminal to transmit setting information, including information about the selected CS and information about the selected OS, to each terminal through the above transceiver (910).

4. In any one of paragraphs 1 to 3, When the above commands are executed individually or collectively by the one or more processors (930), the base station, A base station that further causes the terminals to receive PUCCH signals from the first format-based multiplexed PUCCH resources allocated to the terminals based on the setting information through the above transceiver (910).

5. In any one of paragraphs 1 to 4, When the above commands are executed individually or collectively by the one or more processors (930), the base station, A base station that causes the CS distance to be determined based on the number of terminals allocated PUCCH resources and the OS length.

6. In any one of paragraphs 1 to 5, When the above commands are executed individually or collectively by the one or more processors (930), the base station, A base station that, using the CS allocation method determined above, starts CS allocation to each terminal while maintaining the CS interval within the OS by the CS distance, and causes CS resources to be allocated to each terminal by circulating the OS by the length of the OS NOS.

7. In any one of paragraphs 1 through 6, When the above commands are executed individually or collectively by the one or more processors (930), the base station, Based on the terminal index of each terminal, one of the first CS allocation method and the second CS allocation method is configured to be determined as the CS allocation method. The above second CS allocation method is a base station where CS allocation is performed between CSs first allocated by the above first CS allocation method.

8. In any one of paragraphs 1 through 7, When the above commands are executed individually or collectively by the one or more processors (930), the base station, Causing the second CS allocation method to allocate the initial CS at a distance of offset (CS_dist / 2) from the allocation location of the initial CS in the first CS allocation method, and The above CS_dist is a base station that is the interval between adjacent CSs when allocating PUCCH resources.

9. In any one of paragraphs 1 through 8, When the above commands are executed individually or collectively by the one or more processors (930), the base station, If the terminal index of each terminal allocated the above PUCCH resource is less than or equal to NOS*(12 / CS_dist), the above first CS allocation method is used, and When the terminal index of each terminal allocated the above PUCCH resource is greater than NOS*(12 / CS_dist), the above second CS allocation method is used, and First, the first CS allocation method is performed for a first number of terminals among the above terminals, and Further causing the second CS allocation method to be performed for the remaining second number of terminals, excluding the first number of terminals among the above terminals, and The above NOS is the length of the orthogonal sequence (OS), and the above CS_dist is the base station that is the interval between adjacent CSs during PUCCH resource allocation.

10. In any one of paragraphs 1 through 9, When the above commands are executed individually or collectively by the one or more processors (930), the base station, Correcting the CS allocation location based on the above OS length and the above CS length, and A base station that further causes modulo operations to be performed so that the above-mentioned corrected CS allocation location is within the range of CS indices.

11. A method performed by a base station for allocating PUCCH (physical uplink control channel) resources in a wireless communication system, A process (801) of verifying the indices of the terminals corresponding to the number of terminals (user equipment: UE) for PUCCH resource allocation of the first format; A process (802) for selecting a CS for each terminal using a CS allocation method determined based on the orthogonal sequence (OS) length, cyclic shift (CS) distance, and terminal index of each terminal to be allocated PUCCH resources; A process of selecting an OS for each terminal based on the OS length and the terminal index to be allocated the PUCCH resource (803); and A method comprising the process (805) of allocating PUCCH resources of the first format based on the selected CS and the selected OS for each terminal.

12. In Paragraph 11, A method in which the PUCCH resources of the first format above are multiplexed for the terminals within a single resource block (resource block: RB).

13. In Paragraph 11 or 12, A method further comprising the process (804) of transmitting to each terminal setting information including information about the selected CS and information about the selected OS for each terminal.

14. In any one of paragraphs 11 through 13, A method further comprising the process of receiving PUCCH signals from the first format-based multiplexed PUCCH resources allocated to the terminals based on the above setting information.

15. In a storage medium storing at least one instruction readable by a computer, When the above at least one command is executed individually or collectively by one or more processors including processing circuitry, it causes the base station to perform at least one operation, and The above at least one operation is: An operation (801) to check the indices of the terminals corresponding to the number of terminals (user equipment: UE) for PUCCH resource allocation of the first format; An operation (802) to select a CS for each terminal using a CS allocation method determined based on the length of an orthogonal sequence (OS), a cyclic shift (CS) distance, and the terminal index of each terminal to be allocated a PUCCH resource; An operation (803) to select an OS for each terminal based on the OS length and the terminal index to be allocated the PUCCH resource; and A storage medium comprising an operation (805) of allocating PUCCH resources of the first format based on the selected CS and the selected OS for each terminal.

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