WO2021066389A1

WO2021066389A1 - Method and device for determining priority between scheduling request for secondary cell (scell) beam failure report and other uplink transmissions in wireless communication system

Info

Publication number: WO2021066389A1
Application number: PCT/KR2020/012952
Authority: WO
Inventors: 장재혁; 에기월아닐
Original assignee: 삼성전자 주식회사
Priority date: 2019-10-02
Filing date: 2020-09-24
Publication date: 2021-04-08
Also published as: KR20210039727A

Abstract

The present disclosure relates to a communication technique for combining an IoT technology with a 5G communication system for supporting a higher data transmission rate than a 4G system, and a system therefor. The present disclosure can be applied to intelligent services (for example, smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail businesses, security and safety-related services, and the like) on the basis of 5G communication technologies and IoT-related technologies. According to the present disclosure, a terminal can request for resources by means of a plurality of scheduling requests in accordance with the traffic characteristics and transmission resource request cause and thus can receive an allocation of uplink resources in a timely manner and transmit data.

Description

Method and apparatus for determining priority between scheduling request for SCELL (SECONDARY CELL) beam failure report and other uplink transmission in a wireless communication system

The present invention relates to a method of determining priority between a scheduling request for SCell beam failure report and other uplink transmission in a wireless communication system.

Efforts are being made to develop an improved 5G communication system or a pre-5G communication system in order to meet the increasing demand for wireless data traffic after the commercialization of 4G communication systems. For this reason, the 5G communication system or the pre-5G communication system is called a communication system after a 4G network (Beyond 4G Network) or a system after an LTE system (Post LTE). In order to achieve a high data rate, the 5G communication system is being considered for implementation in the ultra-high frequency (mmWave) band (eg, such as the 60 Giga (60 GHz) band). In order to mitigate the path loss of radio waves in the ultra-high frequency band and increase the transmission distance of radio waves, 5G communication systems include beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO). ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed. In addition, in order to improve the network of the system, in 5G communication system, evolved small cell, advanced small cell, cloud radio access network (cloud RAN), ultra-dense network , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation And other technologies are being developed. In addition, in 5G systems, advanced coding modulation (ACM) methods such as Hybrid FSK and QAM Modulation (FQAM) and SWSC (Sliding Window Superposition Coding), advanced access technologies such as Filter Bank Multi Carrier (FBMC), NOMA (non orthogonal multiple access), and sparse code multiple access (SCMA) are being developed.

Meanwhile, the Internet is evolving from a human-centered connection network in which humans create and consume information, to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. IoE (Internet of Everything) technology, which combines IoT technology with big data processing technology through connection with cloud servers, etc., is also emerging. In order to implement IoT, technological elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required. , M2M), and MTC (Machine Type Communication) technologies are being studied. In the IoT environment, intelligent IT (Internet Technology) services that create new value in human life by collecting and analyzing data generated from connected objects can be provided. IoT is the field of smart home, smart building, smart city, smart car or connected car, smart grid, healthcare, smart home appliance, advanced medical service, etc. through the convergence and combination of existing IT (information technology) technology and various industries. Can be applied to.

Accordingly, various attempts have been made to apply a 5G communication system to an IoT network. For example, technologies such as sensor network, machine to machine (M2M), and machine type communication (MTC) are implemented by techniques such as beamforming, MIMO, and array antenna, which are 5G communication technologies. will be. The application of a cloud radio access network (cloud RAN) as the big data processing technology described above can be said as an example of the convergence of 5G technology and IoT technology.

Meanwhile, when a base station sets a plurality of scheduling request resources in a next-generation mobile communication system, there is a need for a method of using the resources set for the plurality of scheduling requests.

In a wireless communication system, when a scheduling request (SR) transmitted by a terminal to request a transmission resource and data transmission overlap, the need to determine the priority has emerged.

A method for controlling a terminal according to an embodiment of the present invention includes the steps of detecting a beam failure in a secondary cell (scell); Checking whether a resource for transmitting a scheduling request (SR) related to the detected beam failure overlaps in time with a resource for transmitting data; And when the resource for transmitting the SR overlaps in time with the resource for transmitting the data, determining to transmit one of the SR and the data. Including, wherein the determining step, when the resource for transmitting the SR overlaps in time with the resource for transmitting the data, determining to transmit the SR related to the detected beam failure have.

On the other hand, a terminal according to another embodiment of the present invention includes a transceiver; And whether a resource for detecting a beam failure in a secondary cell (scell) and transmitting a scheduling request (SR) related to the detected beam failure overlaps in time with a resource for transmitting data. A control unit configured to determine to transmit one of the SR and the data when the resource for transmitting the SR overlaps in time with the resource for transmitting the data; And when the resource for transmitting the SR overlaps in time with the resource for transmitting the data, the control unit may determine to transmit the SR related to the detected beam failure.

Through the present invention, when a scheduling request (SR) transmitted to make a transmission resource request and data transmission overlap, the terminal can easily determine the priority.

1 is a diagram illustrating a structure of an LTE system referred to for description of the present invention.

2 is a diagram showing a radio protocol structure of an LTE system referred to for description of the present invention.

3 is an exemplary diagram of a downlink and uplink channel frame structure when communication is performed based on a beam in an NR system.

4 is an exemplary diagram for an operation sequence of a terminal performing SR transmission for a SCell BFR MAC Control Element (CE).

5 is a diagram illustrating an exemplary block configuration of a terminal according to an embodiment of the present invention.

6 is a block diagram illustrating an exemplary configuration of a base station according to an embodiment of the present invention.

7 is a flowchart illustrating a method of controlling a terminal according to an embodiment of the present invention.

In describing the embodiments herein, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention by omitting unnecessary description.

For the same reason, some elements in the accompanying drawings are exaggerated, omitted, or schematically illustrated. In addition, the size of each component does not fully reflect the actual size. The same reference numerals are assigned to the same or corresponding components in each drawing.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments make the disclosure of the present invention complete, and the general knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to the possessor, and the invention is only defined by the scope of the claims. The same reference numerals refer to the same elements throughout the specification.

At this time, it will be appreciated that each block of the flowchart diagrams and combinations of the flowchart diagrams may be executed by computer program instructions. Since these computer program instructions can be mounted on the processor of a general purpose computer, special purpose computer or other programmable data processing equipment, the instructions executed by the processor of the computer or other programmable data processing equipment are described in the flowchart block(s). It creates a means to perform functions. These computer program instructions can also be stored in computer-usable or computer-readable memory that can be directed to a computer or other programmable data processing equipment to implement a function in a particular way, so that the computer-usable or computer-readable memory It is also possible for the instructions stored in the flow chart to produce an article of manufacture containing instruction means for performing the functions described in the flowchart block(s). Since computer program instructions can also be mounted on a computer or other programmable data processing equipment, a series of operating steps are performed on a computer or other programmable data processing equipment to create a computer-executable process to create a computer or other programmable data processing equipment. It is also possible for instructions to perform processing equipment to provide steps for executing the functions described in the flowchart block(s).

In addition, each block may represent a module, segment, or part of code that contains one or more executable instructions for executing the specified logical function(s). In addition, it should be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or the blocks may sometimes be executed in the reverse order depending on the corresponding function.

In this case, the term'~ unit' used in this embodiment refers to software or hardware components such as FPGA or ASIC, and'~ unit' performs certain roles. However,'~ part' is not limited to software or hardware. The'~ unit' may be configured to be in an addressable storage medium, or may be configured to reproduce one or more processors. Thus, as an example,'~ unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , Subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. Components and functions provided in the'~ units' may be combined into a smaller number of elements and'~ units', or may be further separated into additional elements and'~ units'. In addition, components and'~ units' may be implemented to play one or more CPUs in a device or a security multimedia card.

With reference to the accompanying drawings will be described in detail the operating principle of the present invention. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of users or operators. Therefore, the definition should be made based on the contents throughout the present specification.

A term for identifying an access node used in the following description, a term for network entities, a term for messages, a term for an interface between network objects, a term for various identification information And the like are illustrated for convenience of description. Accordingly, the present invention is not limited to the terms described below, and other terms referring to objects having an equivalent technical meaning may be used.

For the convenience of description below, the present invention uses terms and names defined in the 3GPP The 3rd Generation Partnership Project Long Term Evolution (LTE) standard, which is the most up-to-date among currently existing communication standards. However, the present invention is not limited by the terms and names, and may be equally applied to systems conforming to other standards. In particular, the present invention can be applied to 3GPP NR (New Radio: 5th generation mobile communication standard).

Referring to FIG. 1, the wireless communication system includes several base stations (1-05) (1-10) (1-15) (1-20) and MME (Mobility Management Entity) (1-20) and S -It is composed of GW (Serving-Gateway)(1-30). User equipment (hereinafter referred to as UE or terminal) (1-35) is external through the base station (1-05) (1-10) (1-15) (1-20) and S-GW (1-30). Connect to the network.

The base stations (1-05) (1-10) (1-15) (1-20) are access nodes of a cellular network and provide wireless access to terminals accessing the network. That is, the base station (1-05) (1-10) (1-15) (1-20) collects status information such as buffer status, available transmission power status, and channel status of terminals to service users' traffic. Thus, the scheduling is performed to support connection between the terminals and the core network (CN). The MME 1-25 is a device in charge of various control functions as well as a mobility management function for a terminal, and is connected to a plurality of base stations, and the S-GW 1-30 is a device that provides a data bearer. In addition, the MME (1-25) and the S-GW (1-30) can further perform authentication, bearer management, etc. for a terminal accessing the network, and the base station 1-05 Processes a packet arriving from (1-10)(1-15)(1-20) or a packet to be delivered to the base station (1-05)(1-10)(1-15)(1-20).

Meanwhile, FIG. 2 is a diagram showing a radio protocol structure of an LTE system referred to for description of the present invention. The NR to be defined in the future may be partially different from the radio protocol structure in this drawing, but will be described for convenience of description of the present invention.

2, the radio protocol of the LTE system is PDCP (Packet Data Convergence Protocol) (2-05) (2-40), RLC (Radio Link Control) (2-10) (2-35) in the terminal and the ENB, respectively. ), MAC (Medium Access Control) (2-15) (2-30). PDCP (Packet Data Convergence Protocol) (2-05)(2-40) is in charge of operations such as IP header compression/restore, and Radio Link Control (hereinafter referred to as RLC) (2-10)(2 -35) reconfigures the PDCP Packet Data Unit (PDU) to an appropriate size. The MAC (2-15) (2-30) is connected to several RLC layer devices configured in one terminal, and performs an operation of multiplexing RLC PDUs to MAC PDUs and demultiplexing RLC PDUs from MAC PDUs. The physical layer (2-20) (2-25) channel-codes and modulates the upper layer data, converts it into OFDM symbols, and transmits it to the radio channel, or demodulates and channel-decodes the OFDM symbol received through the radio channel to the upper layer. It does the act of delivering. In addition, the physical layer also uses HARQ (Hybrid ARQ) for additional error correction, and the receiving end transmits whether or not the packet transmitted by the transmitting end is received in 1 bit. Whether the packet transmitted in 1 bit is received is referred to as HARQ ACK/NACK information. Downlink HARQ ACK/NACK information for uplink transmission is transmitted through a PHICH (Physical Hybrid-ARQ Indicator Channel) physical channel, and uplink HARQ ACK/NACK information for downlink transmission is PUCCH (Physical Uplink Control Channel) or PUSCH. (Physical Uplink Shared Channel) It can be transmitted through a physical channel. The PUCCH is used for the UE to transmit not only the HARQ ACK/NACK information, but also downlink channel status information (CSI, Channel Status Information), scheduling request (SR, Scheduling Request), and the like to the base station. The SR is 1-bit information, and when a terminal transmits an SR to a resource in a PUCCH set by a base station, the base station recognizes that there is data to be transmitted by the corresponding terminal in an uplink, and allocates an uplink resource. The UE may transmit a detailed buffer status report (BSR) message through the uplink resource. The base station can allocate a plurality of SR resources to one terminal.

Meanwhile, the PHY layer may consist of one or a plurality of frequencies/carriers, and a technology in which a plurality of frequencies are simultaneously set and used by one base station is referred to as a carrier aggregation technology (carrier aggreagation, hereinafter referred to as CA). CA technology refers to using only one carrier for communication between a terminal (or user equipment, UE) and a base station (eNB of LTE or gNB of NR), and additionally using a primary carrier and one or a plurality of subcarriers. it means. Accordingly, the amount of transmission can be dramatically increased by the number of additionally used subcarriers. Meanwhile, in LTE, a cell in a base station using a primary carrier is called a PCell (Primary Cell), and a subcarrier is called a SCell (Secondary Cell). A technology in which the CA function is extended to two base stations is referred to as dual connectivity technology (hereinafter referred to as DC). In the DC technology, the terminal is simultaneously connected to a primary base station (Master E-UTRAN NodeB, hereinafter referred to as MeNB) and a secondary base station (Secondary E-UTRAN NodeB, hereinafter referred to as SeNB). Cells belonging to the primary base station are referred to as a master cell group (hereinafter referred to as MCG), and cells belonging to the secondary base station are referred to as a secondary cell group (hereinafter referred to as SCG). There is a representative cell for each cell group, and the representative cell of the primary cell group is referred to as a primary cell (hereinafter referred to as a PCell), and the representative cell of the auxiliary cell group is referred to as a primary secondary cell (hereinafter referred to as a PSCell). do. When using the aforementioned NR, the MCG is used as LTE technology and the SCG is used as the NR, so that the UE can use both LTE and NR at the same time.

Although not shown in this figure, there is an RRC (Radio Resource Control, hereinafter referred to as RRC) layer, respectively, above the PDCP layer of the terminal and the base station, and the RRC layer transmits access and measurement-related configuration control messages for radio resource control. You can give and take. For example, measurement may be instructed to the UE using the message of the RRC layer, and the UE may report the measurement result to the base station using the message of the RRC layer.

In FIG. 3, the base station (3-01) transmits a signal in the form of a beam in order to transmit a wider coverage or stronger signal (3-11)(3-13)(3-15)(3-17). Accordingly, the terminal (3-03) in the cell must transmit and receive data using a specific beam transmitted by the base station (beam #1 (3-13) in this example drawing).

Meanwhile, depending on whether the terminal is connected to the base station, the state of the terminal is divided into a dormant mode (RRC_IDLE) and a connection mode (RRC_CONNECTED). Accordingly, the base station does not know the location of the terminal in the dormant mode.

If the terminal in the dormant mode wants to transition to the connected mode state, the terminal sends a synchronization block (SSB) transmitted by the base station (3-21)(3-23)(3-25)(3-27). ) Can be received. This SSB is an SSB signal periodically transmitted according to a period set by the base station, and each SSB is a Primary Synchronization Signal (PSS) (3-41), a Secondary Synchronization Signal (SSS) (3 -43) and Physical Broadcast Channel (PBCH).

In this example drawing, a scenario in which an SSB is transmitted for each beam is assumed. For example, SSB#0 (3-21) transmits using beam #0 (3-11), and SSB#1 (3-23) transmits using beam #1 (3-13). In the case of transmission using beam #2 (3-15) in case of SSB#2 (3-25), and transmission using beam #3 (3-17) in case of SSB#3 (3-27) Was assumed. In this example drawing, it is assumed that the terminal in the dormant mode is located in beam #1, but even when the terminal in the connected mode performs random access, the terminal may select the SSB received at the time when the random access is performed.

Accordingly, in this drawing, the terminal receives SSB #1 transmitted through beam #1. Upon receiving the SSB #1, the terminal acquires a physical cell identifier (PCI) of the base station through PSS and SSS, and by receiving the PBCH, the identifier of the currently received SSB (i.e., #1) and the current SSB It is possible to determine not only which position within a 10 ms frame is received, but also which SFN within the System Frame Number (SFN) having a period of 10.24 seconds. In addition, a master information block (MIB) is included in the PBCH. The MIB includes information indicating at which location the system information block type 1 (SIB1), which broadcasts more detailed cell configuration information, can be received. Upon receiving SIB1, the terminal can know the total number of SSBs transmitted by the base station, and can perform random access to transition to the connected mode state (e.g., physically designed specifically for uplink synchronization The location of the PRACH occasion (Physical Random Access CHannel) that can transmit a signal, a preamble (in this example drawing, a scenario allocated every 1 ms is assumed (e.g., from (3-30) to (3-39)). In addition, based on the information, it is possible to know which PRACH occasion is mapped to which SSB index among the PRACH occasions For example, in this example drawing, a scenario allocated every 1 ms is assumed, and per PRACH Occasion A scenario in which 1/2 SSBs are allocated (that is, 2 PRACH Occasions per SSB) is assumed, accordingly, a scenario in which 2 PRACH occasions are allocated for each SSB from the start of the PRACH Occasion starting according to the SFN value is shown. For example, (3-30)(3-31) is assigned for SSB#0, (3-32)(3-33) is assigned for SSB#1, and so on. After setting, the PRACH Occasion may be allocated again for the first SSB (3-38)(3-39).

Accordingly, the UE recognizes the location of the PRACH occasion (3-32)(3-33) for SSB#1, and accordingly, the current time among the PRACH Occasions (3-32)(3-33) corresponding to SSB#1 The random access preamble can be transmitted with the fastest PRACH Occasion in (e.g. (3-32)). Since the base station has received the preamble in the PRACH Occasion of (3-32), it can be seen that the corresponding terminal has transmitted the preamble by selecting SSB#1. Accordingly, when performing subsequent random access, data is transmitted and received through the corresponding beam. can do.

Meanwhile, when the connected terminal moves from the current (source) base station to the target (target) base station for reasons such as handover, the terminal performs random access at the target base station, and transmits random access by selecting the SSB as described above. You can perform the operation that you do. In addition, during handover, a handover command is transmitted to the terminal to move from the source base station to the target base station, and in this case, the message is dedicated to the corresponding terminal for each SSB of the target base station so that it can be used when performing random access at the target base station. A random access preamble identifier can be assigned. In this case, the base station may not allocate a dedicated random access preamble identifier for all beams (depending on the current location of the terminal, etc.), and thus, a dedicated random access preamble may not be allocated to some SSBs (e.g., Beam Dedicated random access preamble assigned to #2 and #3 only). If the UE does not have a dedicated random access preamble assigned to the SSB selected for preamble transmission, random access may be performed by randomly selecting a contention-based random access preamble. For example, in this drawing, a scenario in which a UE is located in Beam #1 and performs random access for the first time, but after a failure, is located in Beam #3 and transmits a dedicated preamble when transmitting the random access preamble again, is possible. For example, if preamble retransmission occurs even within one random access procedure, depending on whether a dedicated random access preamble is allocated to the selected SSB for each preamble transmission, a contention-based random access procedure and a contention-based random access procedure May be mixed.

In addition, even when the handover is not performed as described above, if the terminal moves abruptly within one base station, the beam used for current data transmission and reception may escape, and if the base station does not recognize this and does not change the beam, a beam failure may be detected. I can. For example, the UE in the connected state is set up as a message of the RRC layer to tell the base station to detect beam failure for the SSBs corresponding to beam #1 (3-13) and beam #2 (3-15). When moving to this beam #3 (3-17), since both beam #1 and beam #2 are not detected, the physical layer of the terminal can transmit a beam failure instance indication to the MAC layer of the terminal. have. The MAC layer receiving the beam failure occurrence notification starts a beam failure detection timer (or restarts if the beam failure detection timer has already been driven), and may increase the counter (BFI_COUNTER) by 1. If the counter value reaches the threshold (beamFailureInstanceMaxCount) set by the message of the RRC layer (e.g., equal to or greater than), the terminal concludes that a beam failure has occurred and can perform a procedure to recover the beam failure. Yes (beam failure recovery, BFR).

The beam failure may occur in PCell or SCell. For example, in the case of a PCell, when a low frequency that hardly uses a beam is used, and a high frequency that uses a narrow beam in the SCell is used, a beam failure may occur in the SCell.

If a beam failure occurs in the PCell, the terminal can recover using a random access procedure. For example, the base station can allocate a dedicated random access preamble for each beam in preparation for a beam failure to the terminal.For example, if a dedicated preamble identifier is set for beam #3 in this drawing, the terminal detects a beam failure. When beam #3 is selected when performing random access afterwards, the corresponding dedicated preamble identifier is transmitted to immediately inform the base station that the corresponding terminal has selected beam #3 by detecting a beam failure, so that the base station transmits the beam for the corresponding terminal. You can make it adjustable. Alternatively, even if the dedicated random access preamble is not allocated, the terminal may perform contention-based random access to inform the base station that the corresponding terminal is present in the selected beam during the current random access.

If a beam failure occurs in the SCell, the UE may notify the fact that the beam failure has occurred in a certain SCell by transmitting a MAC Control Element (MAC CE), a control message of the MAC layer. More specifically, the MAC CE may include additional information on which SCell has a beam failure and which beam of the corresponding SCell should be used. In order to transmit the MAC CE, the UE needs to request uplink resources from the base station.

Uplink resource requests in the existing LTE and NR are made by transmitting a buffer status report (BSR) MAC CE, and in the case of a regular BSR (Regular BSR) among the conditions in which the BSR transmission is triggered, a scheduling request By triggering (Scheduling Request, SR), 1-bit information is transmitted to the base station in the PUCCH resource allocated for the SR previously allocated as a message of the RRC layer, so that the base station can allocate uplink for transmitting the BSR. have.

The BSR is classified as follows according to the conditions under which transmission is triggered.

-Type 1: Regular BSR

o When the terminal has data that can be transmitted for any logical channel/radio bearer (RB) belonging to a logical channel group (Logical Channel Group, hereinafter referred to as LCG), the BSR retransmission timer (retxBSR-Timer) is BSR sent when expired

o Transmission when data to be transmitted from an upper layer (RLC or PDCP layer) is generated for a logical channel/radio bearer belonging to the above LCG, and this data has a higher priority than a logical channel/radio bearer belonging to a certain LCG. BSR

o BSR transmitted when data to be transmitted from an upper layer (RLC or PDCP layer) is generated for the logical channel/radio bearer belonging to the above LCG and there is no data in any LCG except this data

-2nd type: Periodic BSR

o BSR transmitted when the periodic BSR-Timer set to the terminal expires

-3rd type: Padding BSR

o BSR transmitted when uplink resources are allocated and the padding bit filling the remaining space after transmitting data is equal to or greater than the sum of the size of the BSR MAC CE and the size of the subheader of the BSR MAC CE.

o If there are packets in the buffers of multiple LCGs, Truncated BSR is transmitted

Among the above three types, only Regular BSR is intended to trigger SR. For example, when regular BSR occurs according to the above conditions, it is determined in which logical channel the regular BSR is generated due to data. Accordingly, when there is an SR configuration mapped to a corresponding logical channel, the corresponding SR can be transmitted. For example, the base station may assume a scenario in which three SRs are set to the UE, and SR #1 maps to LCH x and LCH y, and SR #2 to LCH z. Assuming that LCH, x, y, and z have

priorities

1,2,3, if there is traffic only in LCH z in the buffer and data is generated in LCH y, a regular BSR is triggered due to LCH y, Accordingly, SR #1 is triggered.

As described above, since the MAC CE (eg, SCell BFR MAC CE) transmitted to notify the BFR situation in the SCell is not included in any LCG, the Regular BSR cannot be triggered. In addition, in the case of the MAC CE, since the message size difference is not large compared to the BSR MAC CE, it may be unnecessary to transmit the BSR MAC CE to transmit the SCell BFR MAC CE.

Accordingly, it is possible to consider a method of triggering a scheduling request immediately without triggering the Regular BSR in order to transmit the SCell BFR MAC CE.

Meanwhile, the base station may allocate uplink resources at a time when 1-bit scheduling request information transmitted through the PUCCH is transmitted. In general, in the NR system, the UE cannot simultaneously transmit the PUCCH and data (Physical Uplink Shared CHannel: PUSCH: This is used to transmit the UL-SCH). In this case, in the general case, the PUCCH is not transmitted, and data Can only be transmitted. However, if factory automation considered as an operation scenario of 5G and traffic with very high priority occurs suddenly, SR mapped to the traffic with very high priority (logical channel) rather than generating previously generated data. It may be more important to allow the base station to allocate an uplink for transmission of the corresponding traffic by transmitting.

Accordingly, the base station may set the UE as an RRC layer message to determine which one to transmit by comparing the priority between the data to be transmitted and the logical channel mapped to the SR to be transmitted. Accordingly, only when it is set to perform the corresponding determination operation, the terminal may determine which transmission and which are not transmitted when the PUCCH and the PUSCH overlap in time as described above.

If this function is configured for the UE, the UE must determine whether to transmit SR or data for this when transmitting SCell BFR MAC CE.

In the present invention, the following schemes are proposed in a situation in which the UE needs to make a determination when PUCCH and PUSCH resources overlap as described above.

The first scheme is a scheme for always prioritizing the SR for transmitting the SCell BFR MAC CE. Since this is a situation in which communication in the SCell is interrupted, it can be used under the judgment that the SCell should be restored with priority over other data transmission. In this case, uplink data transmission overlapping in time with the SR for transmitting the SCell BFR MAC CE is not performed.

The second method is a method for the base station to set a predetermined threshold to force PUSCH transmission when this situation occurs. In this case, if the priority of a logical channel included in the PUSCH transmission is greater than a preset threshold, PUSCH transmission is performed. Otherwise, the SR for transmitting the SCell BFR MAC CE is prioritized and transmitted.

For example, when the priority of a logical channel included in the PUSCH transmission is greater than (or greater than) a preset threshold, the terminal may perform the PUSCH transmission. And when the priority of the logical channel included in the PUSCH transmission is less than or equal to (or less than) a preset threshold, the UE may transmit an SR for transmitting the SCell BFR MAC CE. At this time, uplink data transmission overlapping in time with the SR for transmitting the SCell BFR MAC CE is not performed.

This scheme can be used as a method for the base station to protect data transmission with very high priority.

The third scheme is a scheme in which PUSCH is always prioritized and transmitted. In this case, when this situation occurs, the SR for transmitting the SCell BFR MAC CE is not always transmitted. For example, when there is an SR for transmitting a PUSCH transmission and a SCell BFR MAC CE overlapping in a resource in time, the UE may perform PUSCH transmission.

This can be used under the assumption that the priority does not need to be very high since communication is still possible in the remaining serving cells (eg, PCell), even though a beam failure occurs in the SCell.

The fourth scheme is to separately set the priority of the SR for transmitting the SCell BFR MAC CE using a message of the RRC layer, and when this situation occurs, the priority (the highest of the logical channels) of the PUSCH to be transmitted and the SCell BFR MAC This is a method of performing transmission having a high priority by comparing the priority set in the SR for transmitting the CE. This is similar to the second scheme, but is a method in which the priorities of the SR for transmitting the SCell BFR MAC CE can be directly signaled and the priorities can be compared with other logical channels.

The fifth scheme is a method of transmitting the PUSCH if the SCell BFR MAC CE is included in the present PUSCH, and if not, prioritizing the SR for transmitting the SCell BFR MAC CE. Using this method, in addition to prioritizing the SR for transmitting the SCell BFR MAC CE, when the PUSCH includes the SCell BFR MAC CE, the corresponding MAC CE is immediately transmitted to allow the base station to transmit the SCell BFR MAC CE as soon as possible. CE information can be transmitted.

When determining which of PUCCH (SR) and PUSCH transmission should be performed, the UE may determine through the above method and perform the corresponding transmission.

4 is an exemplary diagram of an operation sequence of a terminal performing SR transmission for SCell BFR MAC CE.

In FIG. 4, it is assumed that the terminal is connected to the LTE base station and is in a connection mode (RRC_CONNECTED) (4-01). However, since the present invention is not limited to the LTE communication system, the base station to which the terminal is connected may be an NR base station. Thereafter, the UE receives configuration information for a radio bearer and a logical channel related thereto, and SR resources and related configuration information for each logical channel from the base station, and transmits a confirmation message thereon (4-03). The configuration information transmitted by the base station may be received using an RRCReconfiguration message of the RRC layer, and a confirmation message transmitted by the terminal may be transmitted using an RRCReconfigurationComplete message of the RRC layer. The configuration information message may also include configuration information on whether the terminal can report the beam failure when determining the SCell. In addition, when PUCCH transmission for SR transmission and PUSCH overlap in time in time, configuration information on which one to transmit by determining priority may be included. If the separate configuration information for this is not included, the UE prioritizes the PUSCH when the PUCCH transmission and the PUSCH overlap in time.

The terminal receiving the configuration information may determine whether a beam failure occurs for not only the PCell but also the SCell, as described above (4-05). Accordingly, if a beam failure of the SCell is detected, it may be determined whether the PUCCH SR resource is allocated as a message of the RRC layer to transmit the SCell BFR MAC CE (4-07). If a separate SR resource is not allocated, the UE performs a random access procedure and transmits the SCell BFR MAC CE to the base station by including the SCell BFR MAC CE in the Msg3 message of the random access to notify that a beam failure has occurred in a specific SCell (4 -13).

If the base station sets the PUCCH SR resource to transmit the SCell BFR MAC CE, it can be determined whether the corresponding resource overlaps the resource for data transmission dynamically or periodically allocated by the base station (4-09). . If they do not overlap, the UE may transmit the corresponding SR and then transmit the SCell BFR MAC CE to the uplink resource received from the base station (4-15). However, if the PUCCH SR resource and the base station dynamically or periodically allocated a resource for data transmission overlap in time, the terminal may determine whether to compare priorities according to the configuration information of the RRC layer (4 -11). For example, as described above, if the PUCCH SR resource and the PUSCH resource overlap as in this scenario for the purpose of sending a high-priority SR for the purpose of factory automation, etc., whether to additionally determine which one to send first May be set by the base station, and the terminal may determine whether the corresponding configuration information is set. If not configured separately, the UE transmits the PUSCH and the SR for SCell BFR MAC CE transmission attempts to transmit to the next SR resource (4-19), and then determines whether the next PUCCH SR resource overlaps with the PUSCH resource again. Can be judged (4-09). However, if the terminal needs to perform an operation for this, the terminal can determine whether to transmit the PUCCH or the PUSCH according to one of several methods below (4-17).

The first scheme is a scheme for always prioritizing the SR for transmitting the SCell BFR MAC CE. Since this is a situation in which communication in the SCell is interrupted, it can be used under the judgment that it should be restored prior to other data transmission. In this case, uplink data transmission overlapping in time with the SR for transmitting the SCell BFR MAC CE is not performed.

The second method is a method for the base station to set a predetermined threshold to force PUSCH transmission when this situation occurs. In this case, if the priority of a logical channel included in the PUSCH transmission is greater than a preset threshold, PUSCH transmission is performed. Otherwise, the SR for transmitting the SCell BFR MAC CE is prioritized and transmitted. This scheme can be used as a method for the base station to protect data transmission with very high priority.

The third scheme is a scheme in which PUSCH is always prioritized and transmitted. In this case, when this situation occurs, the SR for transmitting the SCell BFR MAC CE is not always transmitted. This can be used under the assumption that the priority does not need to be very high since communication is still possible in the remaining serving cells (eg, PCell), even though a beam failure occurs in the SCell.

Accordingly, when the UE decides to transmit the PUCCH (SR), the UE may transmit the SR and transmit the SCell BFR MAC CE with uplink support received thereafter (4-15). However, if it is decided to transmit the PUSCH, the PUSCH resource is transmitted and the SR transmission is attempted to the next SR PUCCH resource, or if the corresponding PUSCH resource including the SCell BFR MAC CE is transmitted according to the above scheme, the procedure is terminated. can do.

Through the above methods, the terminal notifies the base station of the beam failure of the SCell, and the base station adjusts the beam in the corresponding SCell to recover the beam failure.

5 shows a block configuration of a terminal according to an embodiment of the present invention.

Referring to FIG. 5, the terminal includes a radio frequency (RF) processing unit 5-10, a baseband processing unit 5-20, a storage unit 5-30, and a control unit 5-40. do.

The RF processing unit 5-10 performs a function of transmitting and receiving a signal through a wireless channel such as band conversion and amplification of a signal. That is, the RF processing unit 5-10 up-converts the baseband signal provided from the baseband processing unit 5-20 into an RF band signal and transmits it through an antenna, and the RF band signal received through the antenna Downconvert to a baseband signal. For example, the RF processing unit 5-10 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), and the like. I can. In FIG. 5, only one antenna is shown, but the terminal may include a plurality of antennas. In addition, the RF processing unit 5-10 may include a plurality of RF chains. Further, the RF processing unit 5-10 may perform beamforming. For the beamforming, the RF processing unit 5-10 may adjust a phase and a magnitude of each of signals transmitted/received through a plurality of antennas or antenna elements.

The baseband processing unit 5-20 performs a function of converting between a baseband signal and a bit stream according to the physical layer standard of the system. For example, when transmitting data, the baseband processing unit 5-20 generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit 5-20 restores a received bit stream through demodulation and decoding of the baseband signal provided from the RF processing unit 5-10. For example, in the case of the OFDM (orthogonal frequency division multiplexing) method, when transmitting data, the baseband processor 5-20 generates complex symbols by encoding and modulating a transmission bit stream, and subcarriers the complex symbols. After mapping to, OFDM symbols are constructed through an inverse fast Fourier transform (IFFT) operation and a cyclic prefix (CP) insertion. In addition, when receiving data, the baseband processing unit 5-20 divides the baseband signal provided from the RF processing unit 5-10 in units of OFDM symbols, and applies a fast Fourier transform (FFT) operation to subcarriers. After restoring the mapped signals, the received bit stream is restored through demodulation and decoding.

The baseband processing unit 5-20 and the RF processing unit 5-10 transmit and receive signals as described above. Accordingly, the baseband processing unit 5-20 and the RF processing unit 5-10 may be referred to as a transmission unit, a reception unit, a transmission/reception unit, or a communication unit. In addition, at least one of the baseband processing unit 5-20 and the RF processing unit 5-10 may include different communication modules to process signals of different frequency bands. The different frequency bands may include a super high frequency (SHF) (eg, 2.5GHz, 5Ghz) band, and a millimeter wave (eg, 60GHz) band.

The storage unit 5-30 stores data such as a basic program, an application program, and setting information for the operation of the terminal.

The controller 5-40 controls overall operations of the terminal. For example, the control unit 5-40 transmits and receives signals through the baseband processing unit 5-20 and the RF processing unit 5-10. In addition, the control unit 5-40 writes and reads data in the storage unit 5-40. To this end, the control unit 5-40 may include at least one processor. For example, the controller 5-40 may include a communication processor (CP) that controls communication and an application processor (AP) that controls an upper layer such as an application program. According to an embodiment of the present invention, the control unit 5-40 includes a multiple connection processing unit 5-42 that performs processing for operating in a multiple connection mode. For example, the controller 5-40 may control the terminal to perform a procedure shown in the operation of the terminal illustrated in FIG. 5.

According to an embodiment of the present invention, the UE receives the configuration related to transmission of the SCell BFR MAC CE from the base station, and determines which transmission to perform when PUSCH transmission and SR transmission for transmitting the SCell BFR MAC CE overlap in time. I can.

Meanwhile, FIG. 6 is a diagram showing the structure of a base station according to an embodiment of the present invention.

Referring to FIG. 6, the base station may include a transmission/reception unit 610, a control unit 620, and a storage unit 630. In the present invention, the control unit may be defined as a circuit or an application-specific integrated circuit or at least one processor.

The transceiver 610 may transmit and receive signals with other network entities. The transceiver 610 may transmit, to the terminal, an RRC message including configuration information for a radio bearer and a logical channel related thereto, and SR resources for each logical channel and related configuration information.

The controller 620 may control the overall operation of the base station according to the embodiment proposed in the present invention. For example, the controller 620 may control a signal flow between blocks to perform an operation according to the above-described flowchart. Specifically, the controller 620 may control to generate and transmit the setting information to the terminal according to an embodiment of the present invention. In addition, when an SR for transmitting the SCell BFR MAC CE is received, the control unit 620 may allocate an uplink transmission resource for transmission of the SCell BFR MAC CE to the terminal.

The storage unit 630 may store at least one of information transmitted and received through the transmission/reception unit 610 and information generated through the control unit 520. For example, the storage unit 630 may store configuration information for a radio bearer and a logical channel related thereto, SR resources for each logical channel, and related configuration information.

Meanwhile, FIG. 7 is a flowchart illustrating a method of controlling a terminal according to an embodiment of the present invention. First, in step S700, the terminal may detect a beam failure in a secondary cell (scell).

And in step S710, the terminal may check whether the resource for transmitting a scheduling request (SR) related to the detected beam failure overlaps in time with the resource for transmitting data.

In step S720, when the resource for transmitting the SR overlaps in time with the resource for transmitting the data, the terminal may determine to transmit one of the SR and the data.

The methods according to the embodiments described in the claims or the specification of the present invention may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium are configured to be executable by one or more processors in an electronic device (device). The 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 the present invention.

These programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), and electrically erasable programmable ROM. (EEPROM: Electrically Erasable Programmable Read Only Memory), magnetic disc storage device, Compact Disc-ROM (CD-ROM), Digital Versatile Discs (DVDs), or other types of It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all of them. In addition, a plurality of configuration memories may be included.

In addition, the program is through a communication network composed of 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. It may be stored in an accessible storage device. Such a storage device can access a device performing an embodiment of the present invention through an external port. In addition, a separate storage device on the communication network may access a device performing an embodiment of the present invention.

In the specific embodiments of the present invention described above, the constituent elements included in the invention are expressed in the singular or plural according to the presented specific embodiment. However, the singular or plural expression is selected appropriately for the situation presented for convenience of description, and the present invention is not limited to the singular or plural constituent elements, and even constituent elements expressed in plural are composed of the singular or singular. Even the expressed constituent elements may be composed of pluralities.

Meanwhile, although specific embodiments have been described in the detailed description of the present invention, various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention is limited to the described embodiments and should not be determined, and should be determined by the scope of the claims and equivalents as well as the scope of the claims to be described later.

Claims

In the control method of a terminal in a wireless communication system,

Detecting a beam failure in a secondary cell (scell);

Checking whether a resource for transmitting a scheduling request (SR) related to the detected beam failure overlaps in time with a resource for transmitting data; And

Determining to transmit one of the SR and the data when the resource for transmitting the SR overlaps in time with the resource for transmitting the data; Including,

The determining step,

When the resource for transmitting the SR overlaps in time with the resource for transmitting the data, determining to transmit the SR related to the detected beam failure.
The method of claim 1,

SR related to the detected beam failure,

An SR for requesting uplink data allocation for transmitting a medium access control (MAC) control element (CE) including information on the detected beam failure to a base station. .
The method of claim 1,

The determining step,

Checking a priority of a logical channel related to the data transmission; And

Determining whether the checked priority of the logical channel is greater than a threshold value; And

Determining to transmit the data when the identified priority of the logical channel is greater than the threshold value; The method further comprising a.
The method of claim 3,

The determining step,

Determining to transmit the SR when the identified priority of the logical channel is less than or equal to the threshold value; The method further comprising a.
The method of claim 1,

The determining step,

When the resource for transmitting the SR overlaps in time with the resource for transmitting the data, determining to transmit the data.
The method of claim 1,

The determining step,

Receiving priority setting information for an SR related to the detected beam failure;

Checking a priority of a logical channel related to the data transmission;

Comparing a priority value for an SR related to the detected beam failure included in the configuration information and a priority value for a logical channel related to the data transmission; And

According to the comparison result, when the priority value for the SR related to the detected beam failure included in the setting information is greater than the priority value of the logical channel related to the data transmission, it is determined to transmit the SR, and the setting Determining to transmit the data when the priority value for the SR related to the detected beam failure included in the information is less than the priority value of the logical channel related to the data transmission; Method comprising a.
The method of claim 1,

The determining step,

Determining whether a MAC CE including information on the detected beam failure is included in the data;

If the data includes the MAC CE, determining to transmit the data; And

Determining to transmit the SR if the MAC CE is not included in the data; Method comprising a.
In a terminal in a wireless communication system,

A transmission/reception unit; And

Detecting a beam failure in a secondary cell (scell),

Checking whether the resource for transmitting a scheduling request (SR) related to the detected beam failure overlaps in time with the resource for transmitting data,

A controller configured to determine to transmit one of the SR and the data when the resource for transmitting the SR overlaps in time with the resource for transmitting the data; Including,

The control unit,

When the resource for transmitting the SR overlaps in time with the resource for transmitting the data, the UE determines to transmit the SR related to the detected beam failure.
The method of claim 8,

SR related to the detected beam failure,

UE, characterized in that it is an SR for requesting uplink data allocation for transmitting a medium access control (MAC) control element (CE) including information on the detected beam failure to a base station .
The method of claim 8,

The control unit,

Check the priority of the logical channel related to the data transmission,

It is determined whether the priority of the identified logical channel is greater than a threshold value,

When the priority of the identified logical channel is greater than the threshold value, the terminal, characterized in that to determine to transmit the data.
The method of claim 10,

The control unit,

And if the priority of the identified logical channel is less than or equal to the threshold value, determining to transmit the SR.
The method of claim 8,

The control unit,

When the resource for transmitting the SR overlaps in time with the resource for transmitting the data, determining to transmit the data.
The method of claim 7,

The control unit,

Control the transceiver to receive priority setting information for the SR related to the detected beam failure,

Check the priority of the logical channel related to the data transmission,

Compare a priority value for an SR related to the detected beam failure included in the setting information and a priority value for a logical channel related to the data transmission,

According to the comparison result, when the priority value for the SR related to the detected beam failure included in the setting information is greater than the priority value of the logical channel related to the data transmission, it is determined to transmit the SR, and the setting And determining to transmit the data when the priority value for the SR related to the detected beam failure included in the information is less than the priority value of the logical channel related to the data transmission.
The method of claim 7,

The control unit,

It is determined whether the data includes MAC CE including information on the detected beam failure,

When the data includes the MAC CE, it is determined to transmit the data,

If the MAC CE is not included in the data, the terminal, characterized in that to determine to transmit the SR.