KR20230046941A - Method and apparatus for uplink scheduling - Google Patents

Abstract

Disclosed are a method and an apparatus for resource allocation for a scheduling request in a communication system. A base station operation method includes the following steps of: receiving a scheduling request from a terminal; checking a scheduling request resource identifier and a scheduling request identifier based on an uplink resource having received the scheduling request; checking LCG and LC information mapped to the scheduling request identifier; allocating a time domain resource and a frequency domain resource to the terminal based on the LCG and LC information; transmitting an uplink grant including allocation information of the time domain resource and allocation information of the frequency domain resource to the terminal; and receiving the data from the terminal through the resources indicated by the uplink grant. Therefore, the present invention is capable of improving the performance of a communication system.

Description

Method and apparatus for uplink scheduling {METHOD AND APPARATUS FOR UPLINK SCHEDULING}

The present invention relates to a resource allocation technique for an uplink scheduling request, and more particularly, a base station minimizes reception of a buffer status report (BSR) from a terminal and allows a terminal to perform uplink transmission only by allocating resources for a scheduling request. It's about technology.

To process rapidly increasing radio data, a frequency band (eg, a frequency band of 6 GHz or higher) higher than a frequency band (eg, a frequency band of 6 GHz or lower) of long term evolution (LTE) (or LTE-A) A communication system (eg, a new radio (NR) communication system) using NR is being considered. The NR communication system can support a frequency band of 6 GHz or more as well as a frequency band of 6 GHz or less, and can support various communication services and scenarios compared to the LTE communication system. For example, a usage scenario of the NR communication system may include enhanced mobile broadband (eMBB), ultra reliable low latency communication (URLLC), and massive machine type communication (mMTC). Communication technologies are needed to satisfy the requirements of eMBB, URLLC, and mMTC.

In an NR communication system, a logical channel (LC) may be defined according to QoS characteristics for uplink scheduling suitable for various quality of service (QoS) characteristics, and a terminal may request scheduling for uplink transmission from a base station. there is. However, since the base station cannot determine the size of the data present in the buffer of the terminal from the scheduling request, a procedure for receiving a buffer status report (BSR) may be additionally required, and there is a delay in transmitting uplink data due to the BSR reception procedure. this can happen Therefore, delay may be increased in mission critical services. In addition, due to an increase in the round trip time (RTT) of transmission control protocol (TCP) traffic, there is a limit to increasing the size of the TCP window, and thus downlink traffic performance may deteriorate. Therefore, transmission delay may have a problem of acting as a limitation of NR communication services having various traffic characteristics.

An object of the present invention to solve the above problems is to provide a method and apparatus for a base station to minimize BSR reception from a terminal or to allow a terminal to perform uplink transmission only by allocating resources for a scheduling request without receiving BSR. .

A method of operating a base station according to a first embodiment of the present invention for achieving the above object includes receiving a scheduling request from a terminal, a scheduling request resource identifier and a scheduling request identifier based on an uplink resource from which the scheduling request is received. Checking the LCG (logical channel group) and LC (logical channel) information mapped to the scheduling request identifier, checking the QoS (Quality of Service) information included in the LCG and the LC information Allocating time domain resources to the terminal based on the base station, allocating frequency domain resources to the terminal based on the LCG and buffer status information of the terminal included in the LC information, allocation information of the time domain resources, and Transmitting an uplink grant including allocation information of the frequency domain resources to the terminal, and receiving data from the terminal through a resource indicated by the uplink grant.

Here, the QoS information may be a QoS characteristic of an LCG composed of one or more LCs, and the buffer state information may be an estimated value of the data size stored in the buffer of the terminal.

Here, when the predicted value of the size of the data stored in the buffer of the terminal is smaller than the size of data stored in the buffer of the terminal, the method may further include receiving a buffer status report (BSR) from the terminal.

Here, the buffer status information may be determined based on at least one of a transmission period of the scheduling request, a signal to noise ratio (SNR) of the scheduling request, or a current data rate of the LCG.

Here, the buffer status information may be the size of data stored in the buffer of the UE predicted based on the data rate required by the QoS characteristics of the LCG when the current data rate of the LCG is not measured.

Here, one or more LCs constituting the LCG may have similar QoS characteristics.

Here, one or more LCs constituting the LCG may be mapped to one scheduling request identifier.

Here, when two or more LCs having similar QoS characteristics are mapped to different LCGs, the two or more LCs may be mapped to one scheduling request identifier.

A base station according to a second embodiment of the present invention for achieving the above object includes a processor, a memory that communicates electronically with the processor, and instructions stored in the memory. and, when the commands are executed by the processor, the commands cause the base station to receive a scheduling request from a terminal, and to obtain a scheduling request resource identifier and a scheduling request identifier based on uplink resources from which the scheduling request is received. and checks logical channel group (LCG) and logical channel (LC) information mapped to the scheduling request identifier, and based on quality of service (QoS) information included in the LCG and the LC information, the Allocating time domain resources to the terminal, allocating frequency domain resources to the terminal based on the buffer status information of the terminal included in the LCG and the LC information, and allocating the time domain resource allocation information and the frequency domain resource Transmits an uplink grant including allocation information to the terminal, and causes data to be received from the terminal through a resource indicated by the uplink grant.

Here, the QoS information may be a QoS characteristic of an LCG composed of one or more LCs, and the buffer state information may be an estimated value of the size of data existing in the buffer of the terminal.

Here, when the predicted value of the data size stored in the buffer of the terminal is smaller than the size of data stored in the buffer of the terminal, it may operate to cause a buffer status report (BSR) to be received from the terminal.

Here, the buffer status information may be determined based on at least one of a transmission period of the scheduling request, a signal to noise ratio (SNR) of the scheduling request, or a current data rate of the LCG.

Here, the buffer status information may be the size of data stored in the buffer of the UE predicted based on the data rate required by the QoS characteristics of the LCG when the current data rate of the LCG is not measured.

Here, one or more LCs constituting the LCG may have similar QoS characteristics.

Here, one or more LCs constituting the LCG may be mapped to one scheduling request identifier.

Here, when two or more LCs having similar QoS characteristics are mapped to different LCGs, the two or more LCs may be mapped to one scheduling request identifier.

According to the present invention, a base station can minimize uplink delay by minimizing BSR reception from a terminal or allowing a terminal to transmit uplink data as much as possible only by allocating resources for a scheduling request without receiving BSR. In addition, by reducing the delay of uplink transmission, scheduling services corresponding to various QoS traffic required in the NR communication system can be provided. Therefore, the performance of the communication system can be improved.

1 is a conceptual diagram illustrating a first embodiment of a communication system.
2 is a block diagram showing a first embodiment of a communication node constituting a communication system.
3 is a conceptual diagram illustrating a first embodiment of a method of mapping LCGs and SchedulingRequestIDs to LCs allocated to a terminal.
4A is a conceptual diagram illustrating a first embodiment of a structure of a buffer status report (BSR) media access control (MAC) control element (CE).
4B is a conceptual diagram illustrating a second embodiment of a structure of a buffer status report (BSR) media access control (MAC) control element (CE).
5 is a conceptual diagram illustrating an embodiment of an uplink scheduling method.
6 is a conceptual diagram illustrating a second embodiment of a method of mapping LCGs and SchedulingRequestIDs to LCs allocated to a terminal.
7 is a flowchart illustrating an embodiment of a resource allocation method according to an uplink scheduling request of a terminal.

Since the present invention can make various changes and have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention. The terms and/or include any combination of a plurality of related recited items or any of a plurality of related recited items.

In embodiments of the present application, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B”. Also, in the embodiments of the present application, “one or more of A and B” may mean “one or more of A or B” or “one or more of combinations of one or more of A and B”.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this application, they should not be interpreted in an ideal or excessively formal meaning. don't

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail. In order to facilitate overall understanding in the description of the present invention, the same reference numerals are used for the same components in the drawings, and redundant descriptions of the same components are omitted.

A communication system to which embodiments according to the present invention are applied will be described. A communication system to which embodiments according to the present invention are applied is not limited to the contents described below, and embodiments according to the present invention can be applied to various communication systems. Here, the communication system may be used in the same sense as a communication network.

1 is a conceptual diagram illustrating a first embodiment of a communication system.

Referring to FIG. 1, a communication system 100 includes a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). A plurality of communication nodes are 4G communication (eg, long term evolution (LTE), advanced (LTE-A)), 5G communication (eg, new radio (NR)) specified in the 3rd generation partnership project (3GPP) standard ), etc. can be supported. 4G communication may be performed in a frequency band of 6 GHz or less, and 5G communication may be performed in a frequency band of 6 GHz or more as well as a frequency band of 6 GHz or less.

For example, for 4G communication and 5G communication, a plurality of communication nodes may use a code division multiple access (CDMA)-based communication protocol, a wideband CDMA (WCDMA)-based communication protocol, a time division multiple access (TDMA)-based communication protocol, FDMA (frequency division multiple access)-based communication protocol, OFDM (orthogonal frequency division multiplexing)-based communication protocol, Filtered OFDM-based communication protocol, CP (cyclic prefix)-OFDM-based communication protocol, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) based communication protocol, OFDMA (orthogonal frequency division multiple access) based communication protocol, SC (single carrier)-FDMA based communication protocol, NOMA (Non-orthogonal multiple access), GFDM (generalized frequency) division multiplexing)-based communication protocol, FBMC (filter bank multi-carrier)-based communication protocol, UFMC (universal filtered multi-carrier)-based communication protocol, SDMA (Space Division Multiple Access)-based communication protocol, etc. can be supported. .

In addition, the communication system 100 may further include a core network. When the communication system 100 supports 4G communication, the core network may include a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME), and the like. there is. When the communication system 100 supports 5G communication, the core network may include a user plane function (UPF), a session management function (SMF), an access and mobility management function (AMF), and the like.

Meanwhile, a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-1 constituting the communication system 100 4, 130-5, 130-6) may each have the following structure.

2 is a block diagram showing a first embodiment of a communication node constituting a communication system.

Referring to FIG. 2 , a communication node 200 may include at least one processor 210, a memory 220, and a transceiver 230 connected to a network to perform communication. In addition, the communication node 200 may further include an input interface device 240, an output interface device 250, a storage device 260, and the like. Each component included in the communication node 200 may be connected by a bus 270 to communicate with each other.

However, each component included in the communication node 200 may be connected through an individual interface or an individual bus centered on the processor 210 instead of the common bus 270 . For example, the processor 210 may be connected to at least one of the memory 220, the transmission/reception device 230, the input interface device 240, the output interface device 250, and the storage device 260 through a dedicated interface. .

The processor 210 may execute a program command stored in at least one of the memory 220 and the storage device 260 . The processor 210 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Each of the memory 220 and the storage device 260 may include at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may include at least one of a read only memory (ROM) and a random access memory (RAM).

Referring back to FIG. 1, the communication system 100 includes a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2), a plurality of terminals 130- 1, 130-2, 130-3, 130-4, 130-5, 130-6). Base stations 110-1, 110-2, 110-3, 120-1, and 120-2 and terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 The inclusive communication system 100 may be referred to as an “access network”. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the cell coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the cell coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the cell coverage of the third base station 110-3. there is. The first terminal 130-1 may belong to the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the cell coverage of the fifth base station 120-2.

Here, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a NodeB, an evolved NodeB, a base transceiver station (BTS), Radio base station, radio transceiver, access point, access node, RSU (road side unit), RRH (radio remote head), TP (transmission point), TRP ( transmission and reception ooint), eNB, gNB, etc.

Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 is a UE (user equipment), terminal, access terminal, mobile Mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, IoT (Internet of Thing) It may be referred to as a device, a mounted device (mounted module/device/terminal or on board device/terminal, etc.), and the like.

Next, a downlink scheduling method in NR will be described. Embodiments described below may be applied to other communication systems (eg, LTE) as well as NR. Among the communication nodes, even when a method performed in a first communication node (eg, transmission or reception of a signal) is described, a second communication node corresponding to the method performed in the first communication node and a method (eg, transmission or reception of a signal) corresponding thereto are described. For example, reception or transmission of a signal) may be performed. That is, when the operation of the terminal is described, the corresponding base station may perform an operation corresponding to the operation of the terminal. Conversely, when the operation of the base station is described, a terminal corresponding thereto may perform an operation corresponding to the operation of the base station.

The NR communication system includes enhanced mobile broadband (eMBB), ultra reliable and low latency communication (URLLC) for end-to-end data transmission, and massive machine type communication (mMTC). It may be a communication system that supports. eMBB may be an ultra-broadband and high-speed data transmission service, URLLC may be an ultra-low latency and ultra-reliable transmission service such as autonomous driving, and mMTC may be a large-scale machine-to-machine communication service such as smart metering. In order to provide services with different characteristics, the NR system may additionally define services having new QoS characteristics as shown in Tables 1 to 3 below. In Table 1, a mission critical service may be added to guaranteed bit rate (GBR) services. In Table 2, mission critical services can be added to non-GBR services. In addition, in Table 3, a delay critical GBR service may be added.

In the NR system, for uplink scheduling suitable for various QoS characteristics, a logical channel (LC) may be defined according to the QoS characteristics, and a logical channel group (LCG) grouping LCs having similar QoS characteristics may be defined. there is. The UE may have a large overhead to report the buffer size for all LCs to the base station. Accordingly, the UE may transmit the level of the buffer size of the LCG to the base station as an index for each LCG to which LCs having similar QoS characteristics belong. The base station may receive the index of the buffer size level of the LCG from the terminal. The base station may estimate the buffer size of the LCG based on the index of the buffer size level of the received LCG. One LC can be mapped with one SchedulingRequestID. Therefore, when the base station receives the SchedulingRequestID from the terminal, it can know the mapped LCG and perform scheduling according to the characteristics of the mapped LCG. Here, SchedulingRequestID may be referred to as a scheduling request identifier or SR ID.

3 is a conceptual diagram illustrating a first embodiment of a method of mapping LCGs and SchedulingRequestIDs to LCs allocated to a terminal.

Referring to FIG. 3, the base station may map LCG and SchedulingRequestID to LCs allocated to the terminal. Up to 8 LCGs (eg, LCG #0 to #7) may be configured, and up to 8 SR IDs (eg, SR #0 to #7) may be configured. Signaling radio bearers (SRBs) (eg, SRBs 1 to 3) may be allocated to LCG #0. The priority of SRB 1 may be 1, the priority of SRB 2 may be 3, and the priority of SRB 3 may be 1. Priority 1 may have a higher priority than Priority 2, and Priority 2 may have a higher priority than Priority 3.

Prioritized bit rate (PBR) may be infinite. A data radio bearer (DRB) added thereafter may have logical channel identity (LC ID) values of 3 to 32 (eg, LC 3# to #32). DRB may be assigned to any one of LCGs #0 to #7. Each LC may have a value of any one of priorities 1 to 16. Priority 1 may have the highest priority, priority 16 may have the lowest priority, and priorities 1 to 16 may be sequentially lowered. Each LC may have a PBR value of 0 to 65536 kbps. Each LC may have a value of one of bucket size duration (BSD) 5 to 1000 ms. In addition, parameters necessary for scheduling may be allocated to each LC. One SchedulingRequestID can be assigned to one LC, and one SchedulingRequestID can be mapped to several LCs. One SchedulingRequestID may be mapped to one ScheduligRequestResourceID. The base station may transmit the above-described mapping information to the terminal.

The terminal may transmit a scheduling request to the base station through a specific uplink resource in a specific period and offset. The base station may receive a scheduling request from the terminal through uplink resources. The terminal may receive mapping-related information from the base station. The base station can identify scheduling requests for LCs mapped to SchedulingRequestID through SchedulingRequestID mapped to SchedulingRequestResoureID of the UE. Therefore, the base station can perform scheduling according to the characteristics of LCs. Here, SchedulingRequestResoureID may be called SRResoureID or scheduling request resource identifier.

4A is a conceptual diagram illustrating a first embodiment of a structure of a buffer status report (BSR) media access control (MAC) control element (CE). 4B is a conceptual diagram illustrating a second embodiment of a structure of a buffer status report (BSR) media access control (MAC) control element (CE).

Referring to FIG. 4A, a MAC CE structure for a short BSR or short truncated (ST) BSR may be shown. Referring to FIG. 4B, a MAC CE structure for a long BSR or long truncated (LT) BSR may be shown. The terminal may transmit the BSR to the base station at the time of data arrival, the arrival of high-priority data, the periodic BSR transmission time, or the BSR retransmission time through the empty buffer. The terminal may transmit the BSR to the base station when the padding size of a MAC protocol data unit (PDU) to be transmitted through uplink resources allocated from the base station is greater than the sum of the BSR MAC CE and the MAC header. Long BSR can be used to report BSR for all LCGs. A short BSR may be used when transmitting a BSR for one LCG. The LT BSR can be used for BSR reporting for the LCG with the highest priority when the MAC PDU is not large enough to transmit the long BSR at the time when the long BSR needs to be transmitted. The size of the buffer size field included in the short BSR may be 6 bits, and the size of the buffer size field included in the long BSR may be m octets.

5 is a conceptual diagram illustrating an embodiment of an uplink scheduling method.

Referring to FIG. 5, when data to be transmitted in uplink occurs in the buffer of the LC belonging to LCG #1 of the UE, the UE may request uplink scheduling from the base station. The terminal may transmit a scheduling request to the base station through the uplink resource of the SchedulingRequestResourceID mapped to the SchedulingRequestID allocated to the LC (S501). The base station may receive a scheduling request from the terminal through an uplink resource of SchedulingRequestResourceID (eg, SRResource #1) mapped to SchedulingRequestID allocated to the LC. The base station can identify LCs requiring uplink scheduling through SchedulingRequestResourceID associated with the received scheduling request, and can perform scheduling according to QoS characteristics of the LCs. That is, the base station considers the QoS characteristics (eg, priority level, packet delay budget, and/or packet error rate) of LCs requiring uplink scheduling , scheduling can be performed by determining the timing and scheduling method of scheduling.

However, since the base station cannot know the size of the data existing in the buffer of the terminal until it receives the BSR from the terminal, it is necessary to allocate a certain amount of data and resources capable of transmitting the BSR MAC CE in response to the scheduling request received from the terminal. For this, an uplink (UL) grant may be transmitted to the terminal (S502). A UE may receive a UL grant for a scheduling request from a base station. The terminal may transmit a certain amount of data and a BSR MAC CE to the base station through uplink resources allocated according to the UL grant (S503). The base station may receive a certain amount of data and a BSR MAC CE from the terminal through uplink resources allocated to the terminal. The base station can determine the size of data existing in the buffer of the terminal through a certain amount of data received from the terminal and the BSR MAC CE, and can perform uplink scheduling based on the size of the identified data. Therefore, the base station may transmit the UL grant to the terminal based on the size of data existing in the buffer of the terminal ascertained through the BSR MAC CE (S504). The terminal may receive the UL grant from the base station. The UE may transmit more data and BSR MAC CE than in step S503 according to the UL grant received from the base station (S505). The base station may receive more data and BSR MAC CE from the terminal than in step S503 described above.

That is, since the base station cannot determine the size of data existing in the terminal's buffer only with the scheduling request received from the terminal, a procedure for receiving a BSR from the terminal may be required. However, delay may occur in transmitting and receiving uplink data as the base station performs a procedure for receiving the BSR from the terminal. A delay occurring during uplink transmission may be fatal for mission critical services. In addition, delay occurring during uplink transmission may increase round trip time (RTT) of transmission control protocol (TCP) traffic. Accordingly, since the size of the TCP window may be limited, downlink traffic performance may be degraded.

6 is a conceptual diagram illustrating a second embodiment of a method of mapping LCGs and SchedulingRequestIDs to LCs allocated to a terminal.

Referring to FIG. 6, as an embodiment, a base station may map LCs having similar QoS characteristics to one LCG, and may map one LCG and one SchedulingRequestID. The terminal may transmit a scheduling request to the base station. The base station may receive a scheduling request from the terminal. The base station can check the SchedulingRequestID and can check the LCG mapped with the SchedulingRequestID. The base station can identify LCs having similar QoS characteristics mapped to the LCG. Therefore, the base station can distinguish scheduling requests for LCs having similar QoS characteristics, and can easily identify QoS characteristics to efficiently allocate resources for uplink transmission. As another embodiment, when LCs having similar QoS characteristics are divided into two LCGs, one SchedulingRequestID may be allocated to the two LCGs.

7 is a flowchart illustrating an embodiment of a resource allocation method according to an uplink scheduling request of a terminal.

Referring to FIG. 7, a UE may transmit a scheduling request for uplink transmission to a base station. The base station may receive a scheduling request from the terminal (S701). The base station can check ScheduingRequestResourceID and SchedulingRequestID through the uplink resource to which the terminal has transmitted the scheduling request (S702). The base station can check the information of the LCG and LC mapped to the SchedulingRequestID (S703). The base station may allocate time domain resources for uplink transmission of the terminal to the terminal (S704). The time domain resource may be an offset until the terminal transmits uplink data to the base station after receiving the UL grant containing scheduling information. In the case of URLLC service, the base station may allocate time domain resources to the terminal so that the terminal can transmit uplink data within a very short time. However, in the case of the eMBB/mMTC service, the base station may allocate longer time domain resources to the terminal than the URLLC service.

The base station may allocate frequency domain resources for determining the amount of data transmission to the terminal (S705). The base station may allocate frequency domain resources so as to transmit as much data as possible without wasting resources, rather than allocating only resources capable of transmitting data and BSR MAC CE. Therefore, the base station determines the frequency based on the signal-to-noise ratio (SNR) for the size of the data present in the buffer of the UE predicted based on the current data rate of the LCG and / or the scheduling request. Allocate domain resources. Alternatively, when there is more data in the buffer of the terminal than the size of the data existing in the buffer of the terminal predicted based on the current data rate of the LCG, the base station may receive the BSR from the terminal.

The current data rate of the LCG can be managed by the LCGs data rate management unit. The LCGs data management unit may newly calculate a data rate for LCG of uplink data whenever uplink data is received from the terminal. When the current data rate of the LCG is not measured, the LCGs data management unit may reflect the basic data rate through QoS information of the LCG whose data rate is not measured. The operation of the LCGs data management unit may be executed by a processor included in the base station.

More specifically, the base station may allocate resources capable of achieving the current data rate of the LCG to the UE based on the transmission period of the scheduling request, the SNR for the scheduling request, and/or the current data rate of the LCG. In addition, the base station can minimize resource waste by determining an MCS to be allocated to the terminal based on the SNR for the scheduling request, rather than allocating a low modulation and coding scheme (MCS) for stable reception of BSR information from the terminal. there is. Through the above method, the base station can minimize BSR reception from the terminal. Alternatively, the base station can perform scheduling corresponding to various QoS traffic required in the NR system by minimizing delay occurring during transmission of uplink data by allocating resources only through a scheduling request without receiving BSR.

And the base station may transmit a UL grant to the terminal (S706). The terminal may receive the UL grant from the base station. The UL grant may include time domain resource allocation information in step S704 described above. The UL grant may include frequency domain resource allocation information and/or MCS allocation information in step S705 described above. Upon receiving the UL grant from the base station, the terminal may perform uplink transmission to the base station through time and frequency domain resources allocated by the base station.

The methods according to the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded on a computer readable medium. Computer readable media may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on a computer readable medium may be specially designed and configured for the present invention or may be known and usable to those skilled in computer software.

Examples of computer readable media include hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include high-level language codes that can be executed by a setting computer using an interpreter or the like as well as machine language codes such as those produced by a compiler. The hardware device described above may be configured to operate with at least one software module to perform the operations of the present invention, and vice versa.

Although described with reference to the above embodiments, those skilled in the art will understand that the present invention can be variously modified and changed without departing from the spirit and scope of the present invention described in the claims below. You will be able to.

Claims (16)

As a method of operating a base station,
Receiving a scheduling request from a terminal;
checking a scheduling request resource identifier and a scheduling request identifier based on the uplink resource from which the scheduling request is received;
checking logical channel group (LCG) and logical channel (LC) information mapped to the scheduling request identifier;
allocating time domain resources to the terminal based on the LCG and quality of service (QoS) information included in the LC information;
allocating frequency domain resources to the terminal based on the LCG and buffer status information of the terminal included in the LC information;
Transmitting an uplink grant including allocation information of the time domain resources and allocation information of the frequency domain resources to the terminal; and
And receiving data from the terminal through a resource indicated by the uplink grant. The method of claim 1,
The QoS information is a QoS characteristic of an LCG composed of one or more LCs, and the buffer status information is an estimated value of a data size stored in a buffer of the terminal. The method of claim 2,
When the predicted value of the size of the data stored in the buffer of the terminal is smaller than the size of data stored in the buffer of the terminal, further comprising receiving a buffer status report (BSR) from the terminal. The method of claim 1,
The buffer status information is determined based on at least one of a transmission period of the scheduling request, a signal to noise ratio (SNR) for the scheduling request, or a current data rate of the LCG. Method of operation of a base station. The method of claim 1,
The buffer status information is a size of data stored in the buffer of the terminal predicted based on the data rate required in the QoS characteristic of the LCG when the current data rate of the LCG is not measured. The method of claim 1,
One or more LCs constituting the LCG have similar QoS characteristics. The method of claim 1,
One or more LCs constituting the LCG are mapped to one scheduling request identifier. The method of claim 6,
When two or more LCs having similar QoS characteristics are mapped to different LCGs, the two or more LCs are mapped to one scheduling request identifier. As a base station,
processor;
a memory that communicates electronically with the processor; and
Includes instructions stored in the memory;
When the instructions are executed by the processor, the instructions cause the base station to:
Receive a scheduling request from a terminal;
confirming a scheduling request resource identifier and a scheduling request identifier based on uplink resources from which the scheduling request is received;
Check logical channel group (LCG) and logical channel (LC) information mapped to the scheduling request identifier;
allocating time domain resources to the terminal based on the LCG and quality of service (QoS) information included in the LC information;
allocating frequency domain resources to the terminal based on the LCG and buffer status information of the terminal included in the LC information;
transmitting an uplink grant including allocation information of the time domain resources and allocation information of the frequency domain resources to the terminal; and
A base station that operates to cause receiving data from the terminal through a resource indicated by the uplink grant. The method of claim 9,
The QoS information is a QoS characteristic of an LCG composed of one or more LCs, and the buffer status information is an estimated value of the size of data existing in the buffer of the terminal. The method of claim 10,
When the predicted value of the data size stored in the buffer of the terminal is smaller than the data size stored in the buffer of the terminal, the base station operates to cause a buffer status report (BSR) to be received from the terminal. The method of claim 9,
The buffer status information is determined based on at least one of a transmission period of the scheduling request, a signal to noise ratio (SNR) for the scheduling request, or a current data rate of the LCG. The method of claim 9,
The buffer status information is the size of data stored in the buffer of the UE predicted based on the data rate required in the QoS characteristics of the LCG when the current data rate of the LCG is not measured. The method of claim 9,
One or more LCs constituting the LCG have similar QoS characteristics. The method of claim 9,
One or more LCs constituting the LCG are mapped to one scheduling request identifier. The method of claim 14,
When two or more LCs having similar QoS characteristics are mapped to different LCGs, the two or more LCs are mapped to one scheduling request identifier.

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