KR20180136878A - Methods for configurationing a buffer status report for next-generation mobile communication And Apparatuses thereof - Google Patents

Abstract

The present invention relates to a technique for transmitting and receiving a buffer status report (BSR) in a new radio access network (NR). Specifically, the present invention relates to a method and a device for efficiently transmitting a buffer status report (BSR) on multiple logical channel groups to a base station by a terminal. According to an embodiment of the present invention, the method for transmitting the buffer status report (BSR) by the terminal includes: a step of receiving allocation information on an uplink resource from the base station; a step of determining whether the number of padding bits in accordance with data transmission using the uplink resource is equal to or is greater than a first value, wherein the number of short BSR and the size of a sub-header of the short BSR are added, and is less than a second value, wherein the size of long BSR and the size of the sub-header of the long BSR are added; a step of determining whether available data uplink for uplink transmission exists in the one or more logical channel groups (LCG) in a case that the number of the padding bits is equal to or is greater than the first value and is less than the second value; and a step of transmitting a short truncated BSR or a long truncated BSR to the base station in accordance with a comparison result of the first value and the number of the padding bits in a case that the available data for the uplink transmission exists in the one or more logical channel groups.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a buffer status reporting method for a next generation mobile communication,

This disclosure relates to a technique for transmitting and receiving a buffer status report in a New Radio Access Network (NR). And more particularly, to a method and apparatus for effectively transmitting a buffer status report for a plurality of logical channel groups to a base station.

3GPP recently approved a study item "Study on New Radio Access Technology" for studying next generation / 5G radio access technology, and based on this, RAN WG1 provides frame structure, channel coding and modulation for NR (New Radio) , Waveforms and multiple access methods. NR is required not only to improve data transmission rate in comparison with LTE / LTE-Advanced, but also to design various requirements that are required according to detailed and specific usage scenarios.

In order to meet the requirements of each scenario, LTE / LTE-Advanced has been proposed as a representative use scenario of NR. In this case, enhancement Mobile BroadBand (MMB), massive Machine Type Communication (MMTC) and Ultra Reliable and Low Latency Communications A flexible frame structure design is required.

Thus, it is necessary to provide services such as eMBB and mMTC, which require high-speed large-capacity data processing, and URLLC, which requires high-speed data processing, and efficient scheduling considering various traffic types is required.

However, in the prior art, only the information on the buffer status for the four logical channel groups can be transmitted in the buffer status report, thereby effectively limiting the scheduling. In order to solve this problem, when the buffer status report is transmitted by simply increasing the number of logical channel groups, the overhead of the entire system is increased, and radio resources are wasted.

Therefore, even if the number of logical channel groups increases for efficient scheduling, it is required to develop a technique capable of transmitting a buffer status report with minimizing overhead.

In the foregoing background, the present disclosure is directed to a method and apparatus for transmitting a buffer status report in the event that logical channel groups increase while minimizing the increase in radio resource overhead.

According to an embodiment of the present invention, there is provided a method of transmitting a buffer status report (BSR) by a UE, the method comprising: receiving allocation information on an uplink resource from a base station; Determining whether the number of padding bits according to data transmission is greater than or equal to a first value plus a size of a Short BSR and a size of a Short BSR subheader and less than a second value plus a size of a Long BSR and a size of a Long BSR subheader; Determining whether there is available data for uplink transmission in one or more logical channel groups (LCGs) if the number of padding bits is greater than or equal to a first value and less than a second value, A short truncated BSR or a long truncated BSR according to the comparison result of the number of padding bits and the first value when there is available data for uplink transmission, It provides a method comprising transmitting a station.

According to another aspect of the present invention, there is provided a method of receiving a buffer status report (BSR) in a Node B, the method comprising: transmitting allocation information on an uplink resource to a UE; Receiving short-truncated BSR or long-truncated BSR based on the number of padding bits according to data transmission using uplink resources when there is available data for uplink transmission; Or confirming available data for uplink transmission of one or more logical channel groups of the terminal according to the Long Truncated BSR.

In an exemplary embodiment of the present invention, a UE for transmitting a buffer status report (BSR) includes a receiver for receiving allocation information on an uplink resource from a base station and a receiver for receiving uplink resource allocation information Determining whether the size of the short BSR is less than a first value plus the size of the Short BSR and the size of the Short BSR subheader and less than the second value plus the size of the Long BSR and the size of the Long BSR subheader, 2, a controller for determining whether there is available data for uplink transmission in one or more logical channel groups (LCG), and a controller for determining whether there is available data for uplink transmission in one or more logical channel groups And a transmitter for transmitting a Short Truncated BSR or a Long Truncated BSR to the BS according to a result of comparison between the number of padding bits and the first value, Device.

In an exemplary embodiment of the present invention, a Node B receiving a buffer status report (BSR) includes a transmitter for transmitting allocation information on an uplink resource to a UE and at least one logical channel group A short Truncated BSR or a Long Truncated BSR, which is determined based on the number of padding bits for data transmission using uplink resources when there is available data for uplink transmission, and a Short Truncated BSR or Long And a control unit for checking available data for uplink transmission of one or more logical channel groups of the UE according to the Truncated BSR.

According to the embodiments of the present invention, even when the number of logical channel groups increases, the buffer status report is transmitted with minimized radio resource overhead so that the base station can efficiently perform uplink resource allocation.

1 is a diagram showing an example of a layer 2 structure for a new radio access technology (New RAT).
2 is a diagram illustrating a format of a Short BSR and a Truncated BSR MAC Control Element according to the prior art.
3 is a diagram illustrating a format of a Long BSR MAC control element according to the prior art.
4 is a diagram illustrating an example of a Short BSR or Truncated BSR MAC control element.
5 is a diagram for explaining a terminal operation according to an embodiment.
6 is a diagram illustrating an example of a Short Truncated BSR format according to an embodiment.
FIG. 7 is a diagram illustrating an example of a long truncated BSR format according to an embodiment.
8 is a view for explaining a logical channel group included in a long truncated BSR according to an embodiment.
9 is a view for explaining a base station operation according to an embodiment.
FIG. 10 is a diagram illustrating a table for generating index information included in a 5-bit buffer size field according to an exemplary embodiment of the present invention. Referring to FIG.
11 is a diagram illustrating a table for generating index information included in a 6-bit buffer size field according to an exemplary embodiment of the present invention.
12 is a diagram illustrating a MAC subheader when using a fixed size MAC control element according to an embodiment.
13 is a diagram illustrating a MAC subheader when using a 16-bit L field according to an embodiment.
14 is an exemplary diagram illustrating a Long BSR format set to a specified size according to one embodiment.
15 is an exemplary diagram illustrating a BSR format that specifies the number of logical channel groups over a BSR according to one embodiment.
16 is an exemplary diagram illustrating a Long BSR format according to another embodiment.
17 is an exemplary diagram illustrating a Long BSR format according to another embodiment.
18 is an exemplary diagram illustrating a BSR format using an extended field according to an embodiment.
19 is a diagram illustrating a terminal configuration according to an embodiment.
20 is a diagram illustrating a base station configuration according to an embodiment.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

As used herein, a wireless communication system refers to a system for providing various communication services such as voice, packet data, and the like. A wireless communication system includes a user equipment (UE) and a base station (BS).

The user terminal is a comprehensive concept that means a terminal in a wireless communication, and it is a comprehensive concept which means a mobile station (MS) in GSM, a mobile station (MS) in UT (User Terminal), a Subscriber Station (SS), a wireless device, and the like.

A base station or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B, a gNode-B, a Low Power Node A sector, a site, various types of antennas, a base transceiver system (BTS), an access point, a point (for example, a transmission point, a reception point, a transmission / reception point) (RRH), a radio unit (RU), and a small cell, as well as a relay cell, a relay node, a megacell, a macrocell, a microcell, a picocell, a femtocell, an RRH,

Since the various cells listed above exist in the base station controlling each cell, the base station can be interpreted into two meanings. Macro cell, micro cell, picocell, femtocell, small cell, or 2) the wireless region itself in connection with the wireless region. 1), all of the devices that interact to configure the wireless area to be cooperatively controlled by the same entity are all pointed to the base station. A point, a transmission / reception point, a transmission point, a reception point, and the like are examples of the base station according to the configuration method of the radio area. 2 may direct the base station to the wireless region itself to receive or transmit signals at the point of view of the user terminal or in the vicinity of the neighboring base station.

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or a transmission point or a transmission / reception point of a signal transmitted from a transmission / reception point, and a transmission / reception point itself .

Herein, the user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word Do not.

Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

The time division duplex (TDD) scheme, which is transmitted using different time periods, can be used for the uplink and downlink transmission, and a frequency division duplex (FDD) scheme in which different frequencies are used, a TDD scheme and an FDD scheme A hybrid method can be used.

In the wireless communication system, the uplink and the downlink are configured with reference to one carrier or carrier pair to form a standard.

The uplink and the downlink transmit control information through a control channel such as a physical downlink control channel (PDCCH), a physical uplink control channel (PUCCH), and the like. The physical downlink shared channel (PDSCH), the physical uplink shared channel (PUSCH) It is composed of the same data channel and transmits data.

A downlink may refer to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink may refer to a communication or communication path from a terminal to a multiple transmission / reception point. At this time, in the downlink, the transmitter may be a part of the multiple transmission / reception points, and the receiver may be a part of the terminal. Also, in the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH and PDSCH are transmitted and received'.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The base station performs downlink transmission to the UEs. The base station includes downlink control information, such as scheduling, required for reception of a downlink data channel, which is a primary physical channel for unicast transmission, and physical downlink control information for transmitting scheduling grant information for transmission in an uplink data channel. A control channel can be transmitted. Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

There are no restrictions on multiple access schemes applied in wireless communication systems. (TDMA), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Non-Orthogonal Multiple Access (NOMA) Various multiple access schemes such as OFDM-CDMA can be used. Here, the NOMA includes Sparse Code Multiple Access (SCMA) and Low Density Spreading (LDS).

One embodiment of the present invention relates to asynchronous wireless communications that evolve into LTE / LTE-Advanced, IMT-2020 over GSM, WCDMA, HSPA, and synchronous wireless communications such as CDMA, CDMA- Can be applied.

In this specification, a MTC (Machine Type Communication) terminal may mean a terminal supporting low cost (or low complexity) or a terminal supporting coverage enhancement. Alternatively, the MTC terminal may refer to a terminal defined in a specific category for supporting low cost (or low complexity) and / or coverage enhancement.

In other words, the MTC terminal in this specification may mean a newly defined 3GPP Release-13 low cost (or low complexity) UE category / type for performing LTE-based MTC-related operations. In this specification, the MTC terminal supports the enhanced coverage over the existing LTE coverage, or the UE category / type defined in the existing 3GPP Release-12 or lower that supports the low power consumption, or the newly defined Release-13 low cost low complexity UE category / type. Or a further Enhanced MTC terminal defined in Release-14.

In this specification, NarrowBand Internet of Things (NB-IoT) terminal means a terminal supporting wireless access for cellular IoT. The objectives of NB-IoT technology include improved indoor coverage, support for large-scale low-rate terminals, low latency sensitivity, ultra-low cost, low power consumption, and optimized network architecture.

Enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliable and Low Latency Communication (URLLC) have been proposed as typical usage scenarios in NR (New Radio), which is under discussion in 3GPP.

In this specification, a frequency, a frame, a subframe, a resource, a resource block, a region, a band, a subband, a control channel, a data channel, a synchronization signal, various reference signals, various signals, May be interpreted as past or presently used meanings or various meanings used in the future.

For example, LTE and NR in this specification refer to different radio access technologies, and a new radio access technology under discussion in Release-15 of 3GPP will be described as NR. NR may include various differences such as LTE, frame structure, channel, and core network technology, and various functions for wireless transmission, high-speed, and large-capacity data transmission in the high band can be added.

Hereinafter, for convenience of description, the conventional wireless access technology will be described as LTE and the new wireless access technology discussed in 3GPP will be described as NR. Also, the base station may be an eNB using LTE technology, a gNB using NR technology, and separately described according to need.

The term " cell " used herein refers to a wireless path for transmitting data, a wireless link, a carrier, and the like, and one base station can transmit and receive data through a plurality of cells. Alternatively, a terminal can transmit and receive data using a plurality of cells through cells controlled by two base stations. As described below, carrier merging is described when one base station controls a plurality of cells, and dual connectivity is described when a plurality of cells controlled by two or more base stations are used.

The present disclosure relates to a method and apparatus for configuring a buffer status reporting format in a next generation mobile communication network (NR).

NR (New Radio)

In 3GPP, research is underway on next generation / 5G wireless access technology (hereinafter referred to as NR for convenience of explanation). NR provides a new AS sublayer on top of the PDCP to provide flow-based QoS.

1 is a diagram showing an example of a layer 2 structure for a new radio access technology (New RAT).

As shown in FIG. 1, the main services and functions of the new AS sublayer are as follows.

- Mapping between a QoS flow and a data radio bearer;

- Marking QoS flow ID in both DL and UL packets.

In addition, a new user plane protocol layer can be applied to the connection to the next generation core. A single protocol entity of the new user plane protocol layer can be configured for each individual PDU session (the new user plane protocol layer is applicable to the NextGen Core. A single protocol entity of the new user plane protocol layer is configured for each individual PDU session.).

Buffer status reporting procedure

The buffer status reporting procedure is a procedure used to provide the serving base station with information about data available for transmission in uplink (UL) buffers associated with the MAC entity. The RRC entity configures three timers (e.g. , periodic BSR -Timer , retxBSR-Timer and logicalChannelSR-ProhibitTimer ) and provides buffer status reporting (Buffer) by signaling to allocate a logical channel to a logical channel group for each logical channel Status Repot, BSR) transmission.

The buffer status report should be triggered when the following events occur:

Uplink data is available for one logical channel belonging to one logical channel group (LCG) for transmission in an RLC (Radio Link Control) entity or a PDCP (Packet Data Convergence Protocol) entity. Loses. And the data belongs to one logical channel belonging to any logical channel group and having a higher priority than the priority of logical channels for already available data, or belongs to one logical channel belonging to one logical channel group No data is available for any. In this case, the buffer status report is called " Regular BSR ".

- The buffer status report is called "padding BSR" when the uplink resource is allocated and the number of padding bits is equal to or greater than the size of the buffer status report MAC control element plus its subheader.

- The buffer status report when the retransmission BSR timer (retxBSR-Timer) has expired and the terminal has available data for transmission on any of the logical channels belonging to the LCG is also referred to as " Regular BSR ".

- The buffer status report when the periodic BSR timer (periodic BSR-Timer) expires is called " periodic BSR ".

In addition, the buffer status report can be classified into Short BSR, Truncated BSR, and Long BSR according to the format as well as classification according to the BSR trigger type.

FIG. 2 is a diagram illustrating a Short BSR format according to the prior art, and FIG. 3 is a diagram illustrating a Long BSR format according to the prior art.

For the Regular BSR and Periodic BSR, if the BSR has a Transmission Time Interval (TTI) with more than one LCG available for transmission, it sends a Long BSR (if more than one LCG has data available for transmission in the TTI where the BSR is transmitted: report Long BSR). Otherwise, it sends a Short BSR.

If, for a Padding BSR, the number of padding bits is equal to or greater than the size of the Short BSR plus its subheader, but less than the size of the Long BSR plus its subheader, and if the BSR has more than one LCG in the transmitted TTI If it has the available data, it sends the truncated BSR of the LCG with the highest priority logical channel with available data for transmission (if the number of padding bits is equal to or greater than the size of the Short BSR plus The subheader of the BSR is the subheader of the subheader, which is smaller than the size of the subheader: LCG has more data than available for transmission in the TTI where the BSR is transmitted. transmission; Otherwise, it sends a Short BSR.

Otherwise, if the number of Padding bits is equal to or greater than the size of the Long BSR plus its subheader, then a Long BSR is transmitted.

As shown in FIG. 2, the Short BSR and the Truncated BSR include logical channel group ID information and buffer size information. As shown in FIG. 3, the Long BSR sequentially includes buffer size information for four LCGs.

The BSR is transmitted to the MAC Control Element (MAC CE), and one MAC PDU (Protocol Data Unit) may include at most one MAC BSR control element.

If one BSR is included in one MAC PDU for transmission, all triggered BSRs are canceled.

The MAC entity shall transmit at most one Regular / Periodic BSR within one Transmission Time Interval (TTI).

All BSRs transmitted in one TTI always indicate the buffer status after all MAC PDUs are created for this TTI. Each logical channel group must transmit at most one buffer status value per TTI. And this value should be transmitted in all the BSRs transmitting the buffer status for this logical channel group.

In this specification, the BSR is divided into the Short BSR and the Long BSR, and the format thereof will be described. Meanwhile, Short BSR and Short Truncated BSR can be configured in the same format, and Long BSR and Long Truncated BSR can be configured in the same format. Therefore, Short BSR and Short Truncated BSR can be mixed in terms of format, and Long BSR and Long Truncated BSR can be mixed in terms of format. Therefore, in terms of format, Short BSR and Short Truncated BSR, Long BSR and Long Truncated BSR can be used in the same meaning as needed.

Data available for transmission or data volume

For reporting the buffer status of the MAC layer, the UE shall consider the following as the amount of data available in the RLC layer:

- RLC SDUs not yet included in the RLC data PDU, or segments

- pending RLC data PDUs for retransmission (RLC AM)

- RLC data PDUs pending for initial transmission

For reporting the buffer status of the MAC layer, the UE shall consider the following PDCP control PDUs as the amount of data available in the PDCP layer.

For SDUs whose PDUs are not submitted as lower layers,

- If there is an SDU that has not yet been processed by the PDCP, the SDU itself

- If there is an SDU processed by the PDCP,

PDUs that have not been acknowledged by the lower layer, except for the SDUs that have been successfully delivered by the PDCP status report, starting from the first SDU for delivery of the corresponding PDUs, to the lower layer prior to PDCP reset, For the SDU,

- If there is an SDU that has not yet been processed by the PDCP, the SDU itself

- If there is an SDU processed by the PDCP,

As described above, two types of BSR formats (Short BSR, Long BSR) are supported in the conventional LTE technology. For the Long BSR, only four logical channel groups could be included. In addition to the eMBB service, NR can provide services such as massive MTC service and URLLC service, and efficient scheduling considering various traffic types can be considered. To support this, it is necessary to increase the number of LCGs currently limited to four. However, in this case, the overhead for transmitting the buffer status report to the increased LCG could be increased. In particular, in the present buffer status report format, the buffer size field is composed of 6 bits as shown in FIGS. 2 and 3.

Therefore, if 3 bits are used for the logical channel group identifier (LCG ID) field, the Short BSR and Truncated BSR format of FIG. 2 can be provided as shown in FIG.

4 is a diagram illustrating an example of a Short BSR or Truncated BSR MAC control element.

Referring to FIG. 4, since the LCG ID occupies 3 bits and byte alignment is provided for the corresponding MAC Control elements, 7 reserved bits are used, which is an unnecessary overhead. Therefore, radio resources are wasted.

The present disclosure, which has been devised to solve this problem, provides a MAC PDU format (e.g., BSR format, BSR MAC CE format) capable of providing an efficient buffer status transmission for increasing the number of LCGs currently limited to four And to provide a method and an apparatus for providing the same.

On the other hand, the present disclosure can be applied to any wireless access (e.g., LTE) network / terminal as well as the next generation mobile communication (5G mobile communication / NR) terminal. For convenience of description, the base station may represent an LTE / E-UTRAN eNodeB, an LTE base station, a NRN, a gNB, and a gNB-CU in a 5G wireless network in which a CU (Central Unit) , gNB-DU, or a gNodeB, NR base station in which CU and DU are implemented as a single logical entity. Hereinafter, for the sake of convenience of description, it is denoted as a base station, but all the above-mentioned entities can be included in the category of this term.

In the following, various BSR formats for transmitting a buffer status report for more than 4 logical channel groups to one BSR in order to transmit efficient buffer status information will be described with reference to respective embodiments. For convenience of explanation, the case where there are eight logical channel groups is exemplified, but the number of logical channel groups is not limited thereto. For example, a method of providing a MAC PDU format for effectively transmitting Short BSR or Truncated BSR, Long BSR format, or Truncated BSR will be described. In this specification, the MAC PDU format including the BSR is described in the BSR format or the BSR MAC CE format, and there is no limitation in terms.

In the following embodiments, the BSR format for distinguishing the buffer size in units of logical channel groups is exemplified, but the BSR format for dividing the buffer size in units of logical channels is also included in the scope of the present disclosure.

Also, at least one of the trigger monitoring of the buffer status report, the BSR format determination, and the transmission may be performed in the MAC entity of the UE, although the subject transmitting the buffer status report in this specification is described as an example. Therefore, the following UEs should be interpreted as including the MAC entity of the UE, and may be interpreted as a MAC entity, a MAC layer, or the like.

Each of the embodiments described below may be applied individually or in combination.

5 is a diagram for explaining a terminal operation according to an embodiment.

Referring to FIG. 5, a terminal transmitting a buffer status report (BSR) may perform a step of receiving allocation information on an uplink resource from a base station (S510). For example, the UE can receive allocation information on a radio resource for transmitting uplink data according to the scheduling of the BS. For example, the UE may receive the uplink grant from the Node B and receive information on the radio resources for transmitting the uplink data to the Node B. In another example, the terminal can receive allocation information from the base station via the PDCCH.

If necessary, the terminal may transmit the uplink data to the base station using the allocation information. To this end, the terminal may transmit information for indicating that there is uplink data to be transmitted to the base station.

The UE determines whether the number of padding bits for data transmission using uplink resources is equal to or greater than a first value plus the size of the Short BSR and the size of the Short BSR subheader and is less than a second value plus the size of the Long BSR and the size of the Long BSR subheader (S520). ≪ / RTI > For example, in transmitting uplink data according to allocation information, a mobile station may transmit padding bits to uplink data according to allocated radio resources. In this case, the UE adds a buffer status report to the padding bits and transmits the buffer status report to the BS. Accordingly, the terminal can efficiently transmit the information on the amount of available data to be transmitted to the base station by the terminal, by efficiently utilizing the padding bits.

For example, the UE can compare the number of padding bits with the size of the MAC CE when transmitting the BSR in order to transmit the buffer status report using padding bits. For example, the UE adds the size of the Short BSR to the size of the Short BSR subheader to determine the first value, and compares the first value with the number of the padding bits. In another example, the terminal determines a second value plus the size of the Long BSR and the size of the Long BSR subheader, and compares the determined second value with the number of padding bits. In another example, the terminal determines whether the number of padding bits is equal to or greater than a first value and less than a second value. Based on this result, the UE can determine whether to transmit the padding BSR.

The MS may perform a step of determining whether there is available data for uplink transmission in one or more logical channel groups (LCG) when the number of padding bits is equal to or greater than a first value and less than a second value (S530). If it is determined in step S520 that the number of padding bits is equal to or greater than the first value and less than the second value, the UE can determine whether there is an available data amount for uplink transmission in one or more logical channel groups. That is, the MS determines in step S520 whether the number of padding bits is sufficient to transmit the padding BSR, and determines whether there is available data for BSR transmission in step S530. Based on this, the UE can determine whether to transmit the padding BSR.

The UE performs a step of transmitting a Short Truncated BSR or a Long Truncated BSR to the BS according to the comparison result of the number of padding bits and the first value when there is available data for uplink transmission in one or more logical channel groups (S540). For example, if the number of padding bits exists in a size sufficient to transmit the padding BSR and available data (available data) for uplink transmission exists in one or more logical channel groups, And transmits the BSR according to the result of comparison between the number of one padding bits and the first value.

In this case, the transmitted BSR can be set in the format of the Short Truncated BSR or the Long Truncated BSR and transmitted. The MS may transmit the BSR to the BS using the Short Truncated BSR format when the number of padding bits is equal to the first value. Alternatively, if the number of padding bits exceeds the first value, the terminal may transmit the BSR to the base station using the Long Truncated BSR format.

Hereinafter, the format of the BSRs transmitted by the UE will be described with reference to the drawings. The format of BSR is divided into Short and long. If necessary, Short Truncated BSR and Short BSR can be configured in the same format. Likewise, Long Truncated BSR and Long BSR may be configured in the same format. That is, the truncated BSR is a division according to the transmission mode, but not a format. Therefore, the description of the Short Truncated BSR and the Short BSR in the present specification can be applied mutually exchanged as needed, and the Long Truncated BSR and the Long BSR can be mutually applied as needed.

6 is a diagram illustrating an example of a Short Truncated BSR format according to an embodiment.

Referring to FIG. 6, the Short Truncated BSR may be configured with a logical channel group identification information field and a buffer size field. For example, the logical channel group identification information field may be composed of 3 bits, and the buffer size field may be composed of 5 bits.

In this case, the logical channel group identification information indicates to which logical channel group the amount of available data included in the corresponding BSR is included, and may include logical channel group ID information. The Buffer Size field contains information about the buffer size of the logical channel group indicated by the logical channel group identification information field.

On the other hand, the Short Truncated BSR may include only buffer size information for one logical channel group. Accordingly, the UE must select a logical channel group to be included in the Short Truncated BSR. For example, the UE may include buffer size information for one logical channel group including a logical channel having the highest priority among one or more logical channel groups. That is, the priority information may be set for each logical channel, and the logical channel group means a group for one or more logical channels for which priority information is set. Accordingly, there is a logical channel group to which the logical channel having the highest priority information belongs, and the Short Truncated BSR includes only the buffer size information of one logical channel group including the logical channel having the highest priority.

FIG. 7 is a diagram illustrating an example of a long truncated BSR format according to an embodiment.

Referring to FIG. 7, the Long Truncated BSR may include a logical channel group indication field 710 and buffer size fields 720 and 730. The logical channel group indication field 710 may indicate whether or not the buffer size information for the corresponding logical channel group is included in the corresponding buffer status report (Long Truncated BSR). That is, the logical channel group indication field 710 includes information indicating the presence or absence of the buffer size field for each logical channel group. For example, the logical channel group indication field 710 may be composed of 8-bit bitmaps to indicate whether there are eight buffer size fields 720 and 730 for each logical channel group.

For example, the logical channel group indication field 710 and the buffer size fields 720 and 730 may each be composed of 8 bits, and the logical channel group indication field 710 may include one bit for each logical channel group It is possible to set the case of having uplink data and the case of not having uplink data as 1 and 0 (or 0 and 1). For example, 1 indicates that buffer size information for the logical channel group is reported, and 0 indicates that buffer size information for the logical channel group is not reported. That is, when the value of the logical channel group indication field 710 is set to "01010100 ", buffer size information for logical channel groups 2, 4, and 6 may be included in the corresponding buffer status report.

Through this, it is possible to notify to the base station whether there are available uplink data for each of 8 logical channel groups through 8 bits. In addition, the buffer size field 720, 730 is composed of 8 bits and may include buffer size information for a maximum of 8 logical channel groups.

The buffer size fields 720 and 730 include index information set according to buffer size information of each logical channel group, and the index information may be mapped according to a range of buffer size information and determined according to a predetermined table. For example, the predetermined buffer size range can be mapped to one index. In order to correspond to the 8-bit buffer size information, 256 indexes can be stored in advance in the form of a table in the terminal and the base station. Accordingly, the buffer size field includes the index information designated according to the table, and the base station receiving the buffer status report from the terminal checks the corresponding index information, checks the buffer size range on the table indicated by the corresponding index information, The buffer size information for the logical channel group can be confirmed. For example, the table may be set in a similar form as in Fig. 10 or Fig. FIG. 10 shows an index table when the buffer size field is 5 bits, and FIG. 11 shows an index table when the buffer size field is 6 bits.

8 is a view for explaining a logical channel group included in a long truncated BSR according to an embodiment.

In the case of a long truncated BSR, a buffer status report is transmitted using a padding bit, so that buffer size information of all logical channel groups may not be transmitted. That is, buffer size information that can be transmitted in comparison with the Long BSR may be restricted according to the number of padding bits. Therefore, the UE must select some logical channel group and transmit a Long Truncated BSR.

For example, the Long Truncated BSR may include buffer size information for one or more selected logical channel groups. In this case, one or more selected logical channel groups are selected based on a descending order of priority set for each logical channel, and when there are a plurality of logical channel groups including logical channels having the same priority, logical channel group identification information Can be selected based on ascending order. That is, the one having the higher priority is first selected, and if the priority is the same, the one having the lowest number of the logical channel group identification information (LCG ID) can be selected first.

Referring to FIG. 8, priority information may be set for each logical channel. For example, it is assumed that there are four logical channels and three logical channel groups. Logical channel 1 may be set to priority 5, logical channel 2 may be set to priority 4, and logical channels 3 and 4 may be set to priority 3. The priority may be set dynamically as required, and one or more logical channels may be set to the same priority information. The priority in this description means that the higher the number, the higher the priority, but the present invention is not limited thereto. That is, priority 5 means priority higher than priority 4.

On the other hand, logical channel group 1 may be configured to include logical channels 1 and 2, logical channel group 2 may include logical channel 3, and logical channel group 3 may include logical channel 4.

In this case, the logical channel groups included in the above-described long truncated BSR are selected in order from the highest priority to the lowest priority among the logical channels. Thus, logical channel group 1 containing the two highest priority is first selected. In addition, when logical channel groups can be additionally selected according to the number of padding bits, logical channel group 2 or logical channel group 3 including logical channel 3 or logical channel 4 having the next priority is selected.

However, in this case, since the logical channels have the same priority, the terminal selects the logical channel group identification information based on the ascending order of the logical channel group identification information. That is, because logical channel group 2 has lower identification information than logical channel group 3, the terminal preferentially selects logical channel group 2.

Thus, the logical channel group included in the long truncated BSR is determined according to the priority of the logical channel and the identification information of the logical channel group.

9 is a view for explaining a base station operation according to an embodiment.

Referring to FIG. 9, a BS receiving a buffer status report (BSR) may perform a step of transmitting allocation information on an uplink resource to a UE (S910). For example, the BS may transmit allocation information on a radio resource that the UE can use to transmit uplink data to the UE according to a scheduling request of the UE. For example, the BS may receive the scheduling request from the MS and may transmit the UL grant to the MS. In another example, the base station may transmit allocation information to the terminal through the PDCCH. If necessary, the terminal may transmit the uplink data to the base station using the allocation information. To this end, the terminal may transmit information for indicating that there is uplink data to be transmitted to the base station.

The base station determines whether the available data for uplink transmission exists in one or more logical channel groups (LCGs) of the UE, and determines whether the data is short-truncated based on the number of padding bits according to data transmission using uplink resources. BSR or Long Truncated BSR (S920). For example, the BS may receive the buffer status report of the UE through the padding bits of the uplink data transmitted by the MS. As described above, in this case, the buffer status report can be determined according to the size comparison of the number of padding bits and the Short BSR or the Long BSR MAC CE.

For example, the Short Truncated BSR may be configured such that the number of padding bits is greater than a first value plus the size of the Short BSR and the Short BSR subheader, less than a second value plus the size of the Long BSR plus the size of the Long BSR subheader, Can be received if the number is equal to the first value.

In another example, the Long Truncated BSR may be configured such that the number of padding bits is greater than a first value plus the size of the Short BSR and the Short BSR subheader, less than a second value plus the size of the Long BSR plus the size of the Long BSR subheader, May be received when the number exceeds a first value.

The base station may perform the step of checking available data for uplink transmission of one or more logical channel groups of the UE according to the Short Truncated BSR or the Long Truncated BSR (S930). For example, the base station can acquire information on the amount of available data that the logical channel group of the terminal desires to transmit to the base station through the padding bits of the received uplink data. However, as described above, each BSR includes buffer size information of a logical channel group selected by the UE due to a restriction on the number of padding bits.

In one example, the Short Truncated BSR includes buffer size information for one logical channel group including the logical channel having the highest priority among the one or more logical channel groups, and includes 3 bits of the logical channel group identification information field and 5 Lt; / RTI > buffer size field.

In another example, the Long Truncated BSR may comprise a logical channel group indication field and a buffer size field, and the logical channel group indication field may comprise an 8-bit bitmap to indicate the presence or absence of a buffer size field for each of eight logical channel groups. have. The Long Truncated BSR includes buffer size information for one or more selected logical channel groups. One or more selected logical channel groups are selected based on a descending order of priority set for each logical channel and when a plurality of logical channel groups including logical channels of the same priority exist, .

As described above, the BS receives the BSR from the MS and confirms information on available data for uplink transmission of the MS.

As described above, according to the present embodiment, even when the number of logical channel groups is increased, the UE can transmit accurate buffer size information to the base station while minimizing the system overhead.

Hereinafter, various embodiments will be described in more detail, including the embodiments described with reference to FIGS. 1 to 9. FIG. In the present specification, for convenience of understanding, the BSR format for distinguishing the buffer size in units of logical channel groups has been exemplified. However, the BSR format can also be applied to the BSR format that distinguishes buffer sizes on a logical channel basis.

Each of the embodiments described below may be used independently, or some or all of the embodiments may be used in combination with each other.

First Embodiment: A logical channel group identification information field (LCG  ID field) indicating whether 2-bit or 3-bit is used is referred to as RRC Signaling  How to configure the terminal through

For example, if it is allowed to use 2 bits for the LCG ID field, the Short BSR and Truncated BSR MAC control element format of FIG. 2 described above can be used. Therefore, in this case, a short BSR or a truncated BSR can be transmitted without a 7-bit overhead as shown in FIG. Therefore, unnecessary system overhead may not occur. Although NR can provide various services or traffic types such as massive MTC service or URLLC service in addition to eMBB service in NR, in case of NR (PDU / PDN) session in some cases, logical channel / logical channel group The number may be less than four. Thus, the format of FIG. 2 described above may be used.

However, in a particular case, up to eight logical channels / logical channel group numbers may be provided concurrently through one NR session. In this case, the system overhead problem described above may occur.

Therefore, the base station can control the use of the BSR format by dividing this case.

For example, if the number of logical channel / logical channel groups provided concurrently for one terminal is configured to be less than four (or if the logical channel group ID is to be used for two bits), the base station transmits, via signaling, Short BSR or Truncated BSR MAC control element format.

As another example, if the number of logical channel / logical channel groups to be simultaneously provided for one terminal is to be configured up to eight (or if a logical channel group ID is to be used for three bits) Of the Short BSR or Truncated BSR MAC control element format. Alternatively, the base station may instruct the base station to use the formats of FIGS. That is, the base station can instruct the terminal to use a format in which more than four logical channels or logical channel groups can be BSR-transmitted.

In particular, the terminal may receive information from the base station to indicate the bits of the LCG ID field with 2 bits or 3 bits through RRC signaling (or L2 signaling).

In this way, the terminal can transmit the BSR using both of the formats, and the base station can instruct the terminal to use the format in this case.

Second Embodiment: A method of encoding the buffer size field into 5 bits

For example, if NR is used to increase the number of LCGs to 8 (for example, 3 bits in the LCG ID field), the buffer size (BS) is set to provide the Short BSR or Truncated BSR MAC control element in one byte. ) Field can be encoded into 5 bits and transmitted.

The buffer size level (BS level) is provided as a BS table with coded values, and there can be two BS tables. Both BS tables can be coded into 6 bits. The terminal can construct or use one of the two tables through the information indicated through the RRC signaling. For example, information indicated through RRC signaling is transmitted through the extendedBSR-Sizes field. When the value of the corresponding field is configured, the UE can configure and use extended BSR size levels of two tables.

Accordingly, when eight LCG IDs are used according to the present disclosure, the UE stores a table indicating a plurality of buffer size indexes, and a table to be used may be determined according to an instruction of the BS or fixed for each BSR format. In this case, the bits of the table may be different from those described above. For example, one table may consist of 6 bits, and the other table may consist of 5 bits.

FIG. 10 is a diagram illustrating a table for generating index information included in a 5-bit buffer size field according to an exemplary embodiment of the present invention. Referring to FIG.

For example, referring to FIG. 10, a BS table indicating a buffer size level coded by 5 bits is defined, and a Short BSR or Truncated BSR MAC control element is defined as a 3-bit LCG ID field and a 5-bit buffer size field Can be configured and used. That is, when the buffer size field is composed of 5 bits, an index indicating the level of the buffer size may be included using the table of FIG. For this, the BS can indicate the BSR size to the UE through RRC signaling. Or the base station may indicate using the corresponding BSR format via RRC signaling. Alternatively, the base station may instruct the use of the corresponding BS table through RRC signaling. Or the corresponding BS table can be configured to be used fixedly.

11 is a diagram illustrating a table for generating index information included in a 6-bit buffer size field according to an exemplary embodiment of the present invention.

For another example, a short BSR or a truncated BSR MAC control element can be configured using up to a specific buffer size index available through 5 bits in a conventional 6-bit coded BS table.

If the specific buffer size index is 32, then it can include up to 967 <BS <= 1132 with BS = 0 to index = 31 for the normal BSR size level in the Short BSR or Truncated BSR MAC control element .

If the specific buffer size index is 32, as shown in FIG. 11, 4017 <BS <= 4940 where BS = 0 to index = 31 in the case of the extended BSR size level is set as Short BSR or Truncated BSR MAC control element .

If the specific buffer size index is 31, then the BSR or Truncated BSR MAC control element may include up to 826 <BS <= 967 with index = 0 and BS = 0 to index = 30 for the normal BSR size level. Index = 31 can be set to indicate the case where BS> 967.

If the specific buffer size index is 31, then 3267 <BS <= 4017 with index = 0 BS = 0 to index = 30 for the extended BSR size level can be included in the Short BSR or Truncated BSR MAC control element. Index = 31 may be a case where BS > 4017.

As such, a separate 5-bit buffer size field may be added and used by control of the base station, or a 5-bit buffer size field value may be determined using only a portion of the existing buffer size field.

On the other hand, NR can greatly increase the transmission speed. In this case, a new BS table can be introduced. The use of the corresponding BS table can be configured in the UE through RRC signaling. Or the corresponding BS table can be configured to be used fixedly. As another example, the use of a new BS table may be included and transmitted within the BSR format. In this case, for example, a short BSR or a truncated BSR MAC control element can be configured from a newly coded BS table of 6 bits or 6 bits or more to a specific buffer size index usable through 5 bits.

Third Embodiment: MAC Subheader  Using a single bit on Logical channel ID  How to Direct Information

In LTE, one MAC PDU is composed of a MAC header, zero or more MAC SDUs, zero or more MAC CEs, and optionally padding (MAC PDU consists of a MAC header, zero or more MAC Service Data Units ), zero, or more MAC control elements, and optionally padding). The MAC header is composed of one or more MAC subheaders. Each MAC subheader corresponds to one MAC SDU, one MAC CE or padding (the MAC header consists of one or more MAC sub-headers and each MAC sub-header corresponds to either a MAC SDU, a MAC CE or padding).

In the NR, the MAC subheader does not include an extended field (E field). In the NR, the E field such as LTE is not needed because the MAC subheader is located immediately before the corresponding MAC SDUs, MAC CEs, or perch. NR also does not include the F2 field used to determine the size of the L field to reduce overhead. However, variable length L and F fields with two values are included. F represents a format field and L represents a length field.

12 is a diagram illustrating a MAC subheader when using a fixed size MAC control element according to an embodiment. 13 is a diagram illustrating a MAC subheader when using a 16-bit L field according to an embodiment.

As shown in FIG. 12, the size of the LCID field in NR is 6 bits. This is increased to support more LCID values than LTE. The L field is not included for fixed size MAC CEs. Also, as shown in FIG. 13, the L field is included for a variable size MAC CE. The L field is included for all MAC SDUs.

If the number of LCGs in the NR is increased to 8 (eg 3 bits in the LCG ID field), a certain number of bits on the MAC subheader can be utilized to provide the Short BSR or Truncated BSR MAC control element in one byte have. For convenience of description, a method of utilizing one bit on the MAC subheader is described as an embodiment, but it is also within the scope of this disclosure to utilize one or more bits on the MAC subheader.

For example, the Short BSR or Truncated BSR MAC control element can be composed of a 2-bit LCG ID field and a 6-bit buffer size field.

In order to distinguish 3 bits from LCG ID, it is possible to identify / distinguish / use LCG ID with 3 bits which combine 2 bits of LCG ID of Short BSR or Truncated BSR MAC control element and any one bit of MAC subheader. For example, one bit on the MAC subheader may use one of the R bits on the MAC subheader. As another example, one bit on the MAC subheader may use one of the F bits on the MAC subheader.

For convenience of description, the use of a 16-bit L field is exemplified as shown in FIG. 13, but the use of an arbitrary number of bits as an L field is also included in the scope of the present disclosure.

At this time, it is possible to combine the LCG ID 2 bits and any one bit order on the MAC subheader. Or any one bit on the MAC subheader, in the order of the LCG ID 2 bits.

Fourth Embodiment: MAC Subheader  To indicate buffer size information together using 1 bit on

For example, a Short BSR or Truncated BSR MAC control element can be composed of a 3-bit LCG ID field and a 5-bit buffer size field. However, the buffer size field can transmit the buffer size information using the table from 0 to 63 indexes described above. Therefore, 6-bit buffer size index information can not be transmitted to the buffer size field consisting of 5 bits.

Therefore, in order to use the 6-bit buffer size level separately, 5 bits of the buffer size field of the Short BSR or Truncated BSR MAC control element is combined with any 1 bit on the MAC subheader, and 3 bits are used to identify the LCG ID . For convenience of description, a 6-bit BS table is used. However, it is for convenience of explanation that the use of arbitrary number of bits as a buffer size level is included in the scope of the present disclosure.

For example, one bit on the MAC subheader used to indicate the buffer size field may be one of the R bits on the MAC subheader. As another example, one bit on the MAC subheader may be one of the F bits on the MAC subheader.

At this time, it is possible to combine 5 bits of the buffer size field and any one bit order on the MAC subheader. Or any one bit on the MAC subheader, in the order of the buffer size field 5 bits.

Fifth Embodiment: LCID  through By logical channel group BSR  How to distinguish format

For another example, an LCID can be specified to indicate a Short BSR or Truncated BSR MAC control element for a particular logical channel group. For example, the LCID may have a value different from the LCID of the Short BSR or Truncated BSR MAC control element. For another example, it is possible to have the LCID of the Short BSR control element for a specific logical channel group, respectively.

Another example is to have the LCID of the Truncated BSR MAC control element for a particular logical channel group, respectively.

As described above, in configuring the MAC BSR Control element format according to the present embodiment, the bits included in the MAC BSR Control element field and the bits included in the MAC sub header associated with the MAC BSR Control element field (or an arbitrary (Or bits included in a field of a MAC BSR Control element) to be used as a value of a field included in a MAC BSR Control element (or used to identify a value of a field included in a MAC BSR Control element). This can be applied not only to the MAC BSR Control element but also to any MAC Control element. For example, by using a bit included in an arbitrary MAC Control element field and a bit included in a MAC subheader associated therewith (or a bit included in an arbitrary field included in the associated MAC subheader) It can be used as the value of the field contained in the element (or used to distinguish the value of the field contained in the corresponding MAC Control element).

For example, if a bit included in an arbitrary MAC Control element field and a bit included in a MAC subheader associated with the MAC header (or a bit included in an arbitrary field included in the associated MAC subheader) It can be used as the value of the field included in the header (or used to distinguish the value of the field included in the corresponding MAC subheader).

For another example, combine the bits contained in any Layer 2 header field with the bits contained in any L2 payload associated with it (or the bits contained in any field contained in the associated L2 payload) To be used as the value of the field contained in the L2 payload (or used to distinguish the value of the field contained in the L2 payload).

For another example, combine the bits contained in any Layer 2 header field with the bits contained in any L2 payload associated with it (or the bits contained in any field contained in the associated L2 payload) And can be used as a value of a field included in the corresponding L2 header (or used to identify a value of a field included in the corresponding L2 header).

Hereinafter, an embodiment in which the BSR is effectively transmitted when the number of LCGs is increased to 8 will be further described.

How to use an additional BSR format with a specified size

14 is an exemplary diagram illustrating a Long BSR format set to a specified size according to one embodiment.

For example, the UE can transmit a Short BSR as shown in FIG. 4 if one LCG has available data for transmission in the TTI where the BSR is transmitted.

For another example, the terminal may transmit a Long BSR as shown in FIG. 14 if the BSR has the TTI to which it is transmitted if more than one LCG has available data for transmission.

For another example, the terminal may report a Long BSR as shown in FIG. 14 if the BSR has a TTI to which it is transmitted if more than one LCG has available data for transmission.

For another example, a terminal may transmit a BSR with a particular size if the BSR has a TTI to which it is transmitted if more than one LCG has available data for transmission. The BSR may include one or more fields of a logical channel group ID (LCG ID) field and a buffer size field. The above-described specific size may indicate the number of logical channel groups having available uplink data included in the BSR. Which may be indicated to the terminal by the base station. For example, be directed to the terminal via RRC signaling. For another example, it may be indicated to the terminal via the MAC CE and a Logical Channel ID (LCID) for the MAC CE may be specified.

As another example, a BSR with a specified size can be defined as a truncated BSR. Alternatively, a BSR with the specified size may be used as a new BSR that is distinct from the truncated BSR.

Here, the buffer size field indicates the total amount of available data through one logical channel group after all MAC PDUs are created in the corresponding TTI. The amount of data is indicated by the number of bytes. This can include all data available for transmission in the RLC layer and the PDCP layer (or RLC layer, PDCP layer, New AS sublayer). (The Buffer Size field identifies the total amount of data available for all logical channels of a logical The RLC layer and the PDCP layer are used to transmit the MAC PDUs for the TTI. As an example, the RLC and MAC headers are not considered for buffer size calculation. In another example, the MAC header is not considered in the buffer size calculation, but the RLC header can be considered (included) in the buffer size calculation. This is because RLC headers can be created through preprocessing by removing the concatenation function in the RLC layer, so that it is preferable to include in the calculation for correct buffer size calculation. The definition of the buffer size field described above can be applied to other embodiments as well. As another example, the MAC header and the RLC header can be considered (included) in the buffer size calculation. This is possible when considering new header processing different from LTE.

How to tell the number of logical channel groups with available data for transmission through the BSR

15 is an exemplary diagram illustrating a BSR format that specifies the number of logical channel groups over a BSR according to one embodiment.

For example, the UE may transmit a BSR including the number of logical channel groups if the LCG has available data for transmission in the TTI where the BSR is transmitted.

In another example, the terminal may transmit a BSR including the number of logical channel groups if the BSR has the TTI to which it is transmitted if more than one LCG has available data for transmission.

The BSR stores the number of logical channel groups having available data for transmission (denoted by Length in FIG. 15, which may be another term for convenience of description), a logical channel group ID (LCG ID) field, You can have a buffer size field. The above-mentioned specific size represents the number of logical channel groups included in the BSR.

If there are eight (all) LCGs with available data for transmission, a buffer status report can be generated only in the buffer size field, omitting the LCG ID field.

How to indicate the total buffer size of a logical channel group with available data for transmission

For example, if the UE has available data for transmission of one or more LCGs in the TTI to which the BSR is transmitted, the UE adds up the buffer sizes of all logical channel groups having available data for the corresponding transmission, can do.

That is, the UE can transmit the buffer status report to the BS by including information on all available data, instead of dividing the buffer size information for each logical channel group, into one buffer size information.

A method of indicating a buffer size of a sum of available data for transmission of the remaining logical channel groups

For example, if the terminal has one or more LCGs available for transmission in the TTI to which the BSR is to be transmitted, the terminal determines the logical channel group ID for the LCG having the highest priority, the buffer size for the LCG ID, The buffer size can be indicated to the BSR by summing the available data for the LCG ID with the available data for the remaining transmissions.

For another example, if the terminal has the TTI to which the BSR is transmitted, if one or more LCGs have available data for transmission, the terminal may determine the logical channel group ID for a particular number of LCGs, the buffer size for that LCG ID, The buffer size can be indicated to the BSR by summing the available data for the LCG ID with the available data for that buffer. In this case, logical channel group IDs for a certain number of LCGs may be included in order of priority. The specific number may be pre-configured in the terminal or indicated by the base station. For example, a particular number may be indicated to the terminal via RRC signaling. As another example, the specific number may be indicated to the terminal via the MAC CE, and the LCID for the MAC CE may be specified. As another example, a specific number may be included in the BSR and transmitted.

A method of indicating a BSR by defining a field indicating whether or not each logical channel group is included

For example, the NR may report the BSR by defining a field indicating whether each logical channel group is included if the TTI having the BSR has available data for transmission, if one LCG has available data for transmission.

For another example, the NR may report a BSR by defining a field indicating whether each logical channel group is included if the BSR has a TTI to which it is transmitted if more than one LCG has available data for transmission.

The BSR may comprise a field indicating whether each logical channel group is included and a buffer size field. The field indicating whether or not each of the logical channel groups is included can be designated by setting 1 and 0 (or 0 and 1) and not having the uplink data available with 1 bit for each logical channel group have. And may indicate whether it has available uplink data for each of the eight logical channel groups through eight bits (each bit can be represented as LI0 to LI7 or LI1 to LI8).

16 is an exemplary diagram illustrating a Long BSR format according to another embodiment.

The logical channel group indexes of the logical channel group indication fields may be set to be included in the ascending order as shown in FIG. 16 or 17.

Referring to FIG. 16, when the value of the logical channel group indication field is set to "01010100 ", buffer size information for logical channel groups 2, 4, and 6 may be included in the corresponding buffer status report. The buffer size field may be composed of 6 bits as described above or 8 bits as shown in FIG.

17 is an exemplary diagram illustrating a Long BSR format according to another embodiment.

Referring to FIG. 17, the above-described Long BSR may include a logical channel group indication field and a buffer size (B / S) field indicating whether each logical channel group is included. The buffer size field may also be composed of 8 bits and may include only the buffer size information for the logical channel group indicated in the logical channel group indication field.

For example, the buffer size field may include only the buffer size of available uplink data of a logical channel group having available uplink data. For example, as shown in FIG. 6, when eight bits of the logical channel group indication field are "01010100" (when the second, fourth, and sixth logical channel groups have available uplink data) 4 &lt; th &gt; and 6 &lt; th &gt; logical channel groups. In this case, the buffer size field may be included according to an ascending priority order. For example, as shown in FIG. 17, buffer size information for the second and fourth 6th logical channel groups may be sequentially included. Or the buffer size field may be included in the same order as the order of the logical channel group indication field. For example, buffer size information for the sixth, fourth, and second logical channel groups may be sequentially included.

As another example, the buffer size field may include the buffer size of the available uplink data of all logical channel groups.

As another example, it may include the buffer size of the data included in the logical channel group according to the priority.

To this end, the terminal may perform a step of monitoring a trigger of a regular buffer status report (Regular BSR) or a periodic buffer status report (Periodic BSR). For example, the terminal may monitor whether or not a buffer status report is triggered. The UE may configure three timers (e.g., periodic BSR-Timer, retxBSR-Timer and logicalChannelSR-ProhibitTimer) and monitor whether the trigger is triggered using a periodic BSR timer and a retransmission BSR timer. In addition, it is possible to monitor whether or not the buffer status report is triggered and whether the buffer status report to be transmitted is a regular buffer status report or a cyclic buffer status report by monitoring whether the BSR event is generated or not. In addition, the UE may monitor the padding BSR if necessary.

If there is available data for uplink transmission in one or more logical channel groups (LCG), the UE may perform the step of determining the buffer status reporting format as Long BSR. The terminal may determine the BSR format for buffer status reporting. For example, the UE may determine the BSR format to be a Long BSR in order to transmit it if there is available data for uplink transmission in one or more logical channel groups in one transmission time unit (TTI). The above-mentioned transmission time unit (TTI) may mean any physical layer transmission time unit defined in NR. For example, one subframe, one slot, one minislot, n minislots, n slots, n symbols (where n is a natural number), which can be configured in the terminal by the base station via the RRC message. In another example, the UE may determine the BSR format to be a Long BSR in order to transmit the available data for uplink transmission to one or more logical channel groups when the BSR is transmitted. For another example, the terminal may determine the BSR format to be a Long BSR in order to transmit it if there is available data for uplink transmission in one or more logical channel groups when the BSR is triggered.

After the normal buffer status report or the cyclic buffer status report is triggered, the UE transmits a buffer status report for all logical channel groups having data available for uplink transmission configured in the Long BSR format to the base station . When there is available data for uplink transmission in one or more logical channel groups when the BSR is transmitted, a buffer status report for all logical channel groups having available data for regular buffer status reporting or periodic buffer status reporting, Lt; / RTI &gt;

For example, the UE may transmit a buffer status report of the Long BSR format to the BS through the normal BSR or the periodic BSR to inform the BS of the buffer status information of the UE.

For example, a buffer status report configured in Long BSR format may include a logical channel group indication field and a buffer size field. In this case, the logical channel group indication field includes information indicating whether or not the buffer size field for each logical channel group is present in the buffer status report. In addition, the logical channel group indication field may comprise an 8-bit bitmap indicating the presence or absence of a buffer size field for each logical channel group.

The logical channel group indication field indicates whether a buffer size field for each logical channel group exists for eight logical channel groups. The buffer size field indicates that only buffer size information for a logical channel group having available data has an ascending priority . &Lt; / RTI &gt;

The buffer size field is composed of 8 bits for each logical channel group and includes index information set according to buffer size information of each logical channel group. The index information is mapped according to a range of buffer size information and is determined according to a preset table .

In this manner, when the Long BSR format is set to transmit the buffer status report including the buffer status information for all the logical channel groups in which the UE has available data, in order to minimize the overhead, The Long BSR format can be configured to include a buffer size field in which buffer status information is present.

Of course, as described above, the above-described format of FIG. 16 or 17 may be applied when the BSR is transmitted through the padding bits.

How to define an extended field to indicate whether there is a logical channel added to the BSR

For example, if the MS has available data for transmission, the MS can transmit the BSR by defining an extended field in the TTI where the BSR is transmitted.

For another example, if the terminal has one or more LCGs available for transmission in the TTI where the BSR is transmitted, the terminal may define an extended field to transmit the BSR.

The BSR may include a buffer size per logical channel group according to a priority for a logical channel group having available data for transmission. The BSR may include one or more of an LCG ID field, a buffer size field, and an extension field.

The extension field contains flags (1 and 0 (or 0 and 1) to indicate if there are additional logical channel groups with data available after the logical channel group (if more LCG (s) is / Quot; field &quot; field).

For convenience of description, the corresponding field is denoted by an extension field (E in FIG. 18). It is for convenience of explanation only and may be any other name.

18 is an exemplary diagram illustrating a BSR format using an extended field according to an embodiment.

Referring to FIG. 18, when the highest priority LCG ID is LCG ID 1, LCG ID 1 is included first. If there is data available for LCG ID 1 and LCG ID 2 and there is an added logical channel group with data for which the extension field is available, the first E is 1, the second E is the 1st E is set to zero.

How to direct multiple LCGs to a truncated BSR

If, for a Padding BSR, the number of padding bits is equal to or greater than the size of the Short BSR plus its subheader, but less than the size of the Long BSR plus its subheader, and if the BSR has more than one LCG in the transmitted TTI If it has the available data, it sends the Truncated BSR of the LCG with the highest priority logical channel with available data for transmission. In conventional LTE technology, the Padding BSR or the Truncated BSR only transmitted the buffer size for one logical channel with the highest priority. NR to send the buffer size of one or more LCGs to the Padding BSR or the Truncated BSR. For example, the above-described methods can be used individually or in combination. As another example, it is possible to transmit the buffer size in order of priority to as many logical channel groups as possible within the number of padding bits.

How to use the integrated BSR format

For example, one of the methods described above may be used to perform buffer state transmission using one integrated BSR format.

For another example, buffer status transmission may be performed using an integrated BSR format for a triggered BS or Triggered logical channel group either following an existing trigger criterion or after defining a particular trigger criterion.

As described above, according to the present invention, a UE can transmit buffer state information for a logical channel group having a number of logical channel groups that are conventionally transmitted to a base station while minimizing radio resource overhead.

A configuration of a terminal and a base station capable of performing some or all of the operations of the above-described embodiments will be described once more with reference to the drawings.

19 is a diagram illustrating a terminal configuration according to an embodiment.

Referring to FIG. 19, a UE 1900 for transmitting a buffer status report (BSR) includes a receiver 1930 for receiving allocation information on an uplink resource from a base station, Determining whether the number of padding bits is greater than or equal to a first value plus the size of the Short BSR and the size of the Short BSR subheader and less than a second value plus the size of the Long BSR and the size of the Long BSR subheader, A control unit 1910 for determining whether there is available data for uplink transmission in one or more logical channel groups (LCGs) in the case that the number of available channels is less than a second value, and an uplink transmission to one or more logical channel groups And a transmitter 1920 for transmitting a Short Truncated BSR or a Long Truncated BSR to the BS according to a result of comparison between the number of padding bits and the first value in the presence of available data Can.

For example, the receiving unit 1930 can receive allocation information on a radio resource for transmitting uplink data according to the scheduling of the base station. For example, the receiver 1930 can receive the uplink grant from the base station and receive information on the radio resources for transmitting the uplink data to the base station. In another example, the terminal can receive allocation information from the base station via the PDCCH.

If necessary, the transmitter 1920 may transmit the uplink data to the base station using the allocation information. To this end, the transmitter 1920 may transmit information for indicating the presence of uplink data to be transmitted to the base station .

Meanwhile, the transmitter 1920 may transmit the uplink data by adding the padding bits to the uplink data according to the allocated radio resources when transmitting the uplink data according to the allocation information. In this case, the transmitter 1920 may add a buffer status report to the padding bits and transmit the buffer status report to the base station. Accordingly, the terminal 1900 can efficiently transmit the information on the amount of usable data to be transmitted to the base station by the terminal to the base station by efficiently utilizing the padding bits.

For example, the control unit 1910 may compare the number of padding bits with the size of the MAC CE when transmitting the BSR in order to transmit the buffer status report using the padding bits. For example, the control unit 1910 determines the first value by adding the size of the Short BSR to the size of the Short BSR subheader, and compares the first value with the number of the padding bits. As another example, the controller 1910 determines a second value that is the sum of the size of the Long BSR and the size of the Long BSR subheader, and compares the determined second value with the number of padding bits. As another example, the control unit 1910 determines whether the number of padding bits is equal to or greater than the first value and less than the second value. Referring to this result, the control unit 1910 can determine whether to transmit the padding BSR.

If the number of padding bits is greater than or equal to the first value and less than the second value, the control unit 1910 can determine whether there is an available data amount for uplink transmission in one or more logical channel groups. That is, the controller 1910 determines whether there is sufficient space for the padding BSR to transmit the number of padding bits, and determines whether there is available data for the BSR transmission. Based on this, the control unit 1910 can determine whether to transmit the padding BSR.

The control unit 1910 determines whether the number of padding bits exists in a size sufficient to transmit the padding BSR and the number of padding bits in a case where available data (available data) for uplink transmission exists in one or more logical channel groups And determines the BSR format according to the comparison result of the first value. In this case, the BSR can be set and transmitted in the format of a Short Truncated BSR or a Long Truncated BSR. If the number of padding bits is equal to the first value, the controller 1910 may control to transmit the BSR to the BS using the short truncated BSR format. Alternatively, when the number of padding bits exceeds the first value, the controller 1910 may control to transmit the BSR to the base station using the long truncated BSR format.

In addition, the control unit 1910 may separately or variably combine various embodiments for efficiently transmitting BSRs for a logical channel group when the number of logical channel groups required to perform all of the embodiments increases, And controls the overall operation of the terminal. The transmitting unit 1920 and the receiving unit 1930 are used to transmit and receive signals, messages, and data necessary for performing the above-described present disclosure to and from the base station.

20 is a diagram illustrating a base station configuration according to an embodiment.

Referring to FIG. 20, a BS 2000 receiving a buffer status report (BSR) includes a transmitter 2020 for transmitting uplink resource allocation information to a UE, and a logical channel group Channel group (LCG) receives a Short Truncated BSR or a Long Truncated BSR, which is determined based on the number of padding bits according to data transmission using uplink resources when there is available data for uplink transmission And a control unit 2010 for checking available data for uplink transmission of one or more logical channel groups of the UE according to a Short Truncated BSR or Long Truncated BSR.

The transmitting unit 2020 can transmit allocation information on a radio resource that the UE can use to transmit uplink data to the UE according to a scheduling request of the UE. For example, the receiving unit 2030 may receive the scheduling request from the terminal, and the transmitting unit 2020 may transmit the uplink grant at the terminal. As another example, the transmitter 2020 can transmit allocation information to the UE through the PDCCH. If necessary, the terminal may transmit the uplink data to the base station 2000 using the allocation information. In order to do so, the terminal may transmit information for indicating the presence of uplink data to be transmitted to the base station 2000 .

Meanwhile, the receiving unit 2030 can receive the buffer status report of the UE through the padding bits of the uplink data transmitted by the UE. As described above, in this case, the buffer status report can be determined according to the size comparison of the number of padding bits and the Short BSR or the Long BSR MAC CE.

For example, the Short Truncated BSR may be configured such that the number of padding bits is greater than a first value plus the size of the Short BSR and the Short BSR subheader, less than a second value plus the size of the Long BSR plus the size of the Long BSR subheader, Can be received if the number is equal to the first value.

In another example, the Long Truncated BSR may be configured such that the number of padding bits is greater than a first value plus the size of the Short BSR and the Short BSR subheader, less than a second value plus the size of the Long BSR plus the size of the Long BSR subheader, May be received when the number exceeds a first value.

The control unit 2010 can obtain information on the amount of available data to be transmitted to the base station by the logical channel group of the UE through the padding bits of the received uplink data. However, as described above, each BSR includes buffer size information of a logical channel group selected by the UE due to a restriction on the number of padding bits.

In one example, the Short Truncated BSR includes buffer size information for one logical channel group including the logical channel having the highest priority among the one or more logical channel groups, and includes 3 bits of the logical channel group identification information field and 5 Lt; / RTI &gt; buffer size field.

In another example, the Long Truncated BSR may comprise a logical channel group indication field and a buffer size field, and the logical channel group indication field may comprise an 8-bit bitmap to indicate the presence or absence of a buffer size field for each of eight logical channel groups. have. The Long Truncated BSR includes buffer size information for one or more selected logical channel groups. One or more selected logical channel groups are selected based on a descending order of priority set for each logical channel and when a plurality of logical channel groups including logical channels of the same priority exist, .

In this manner, the control unit 2010 can receive information on available data for uplink transmission of the UE by receiving the BSR from the UE.

In addition, the control unit 2010 may independently or variably combine various embodiments for efficiently transmitting the BSR for the logical channel group when the number of logical channel groups required to perform all of the embodiments increases, Thereby controlling the overall operation of the base station. The transmitting unit 2020 and the receiving unit 2030 are used to transmit and receive signals, messages, and data necessary for performing the above-described present disclosure to and from the terminal.

The standard content or standard documents referred to in the above-mentioned embodiments constitute a part of this specification, for the sake of simplicity of description of the specification. Therefore, it is to be understood that the content of the above standard content and portions of the standard documents are added to or contained in the scope of the present invention.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (24)

A method for transmitting a buffer status report (BSR)
Receiving allocation information on an uplink resource from a base station;
Wherein a number of padding bits according to data transmission using the uplink resource is equal to or larger than a first value plus a size of a Short BSR and a size of the Short BSR subheader and less than a second value plus a size of a Long BSR and a size of the Long BSR subheader Judging whether or not it is;
Determining whether there is available data for uplink transmission in at least one logical channel group (LCG) when the number of padding bits is greater than or equal to the first value and less than the second value; And
If there is available data for uplink transmission in the at least one logical channel group, transmitting a Short Truncated BSR or a Long Truncated BSR to the BS according to a result of comparison between the number of padding bits and the first value Methods of inclusion. The method according to claim 1,
Wherein the transmitting comprises:
And transmitting the Short Truncated BSR when the number of the padding bits is equal to the first value,
And if the number of padding bits exceeds the first value, transmitting the long truncated BSR. The method according to claim 1,
The Short Truncated BSR includes:
And buffer size information for one logical channel group including a logical channel having the highest priority among the one or more logical channel groups,
A 3-bit logical channel group identification information field, and a 5-bit buffer size field. The method according to claim 1,
The long-truncated BSR includes:
A logical channel group indication field, and a buffer size field,
Wherein the logical channel group indication field indicates the presence or absence of a buffer size field for each logical channel group. 5. The method of claim 4,
The logical channel group indication field includes:
Wherein the buffer size field is composed of 8 bits of bitmap and indicates whether the buffer size field exists for each of eight logical channel groups. 5. The method of claim 4,
The buffer size field may comprise:
And index information which is composed of 8 bits for each logical channel group and is set according to buffer size information of each logical channel group,
Wherein the index information is mapped according to a range of buffer size information and is determined according to a preset table. 5. The method of claim 4,
The long-truncated BSR includes:
Buffer size information for one or more selected logical channel groups,
Wherein the one or more selected logical channel groups comprise:
And the logical channel group identification information is selected based on the ascending order of the logical channel group identification information when a plurality of logical channel groups including the logical channels having the same priority are present, How to. A method for a base station to receive a buffer status report (BSR)
Transmitting allocation information on an uplink resource to a terminal;
Determined by the number of padding bits according to data transmission using the uplink resource when there is available data for uplink transmission in at least one logical channel group (LCG) of the UE, Receiving a BSR or Long Truncated BSR; And
Identifying available data for uplink transmission of one or more logical channel groups of the terminal according to the Short Truncated BSR or Long Truncated BSR. 9. The method of claim 8,
The Short Truncated BSR includes:
Wherein the number of padding bits is equal to or greater than a first value plus the size of the Short BSR and the size of the Short BSR subheader and less than a second value plus the size of the Long BSR and the size of the Long BSR subheader,
And when the number of padding bits is equal to the first value. 9. The method of claim 8,
The long-truncated BSR includes:
Wherein the number of padding bits is equal to or greater than a first value plus the size of the Short BSR and the size of the Short BSR subheader and less than a second value plus the size of the Long BSR and the size of the Long BSR subheader,
And when the number of padding bits exceeds the first value. 9. The method of claim 8,
The Short Truncated BSR includes:
And buffer size information for one logical channel group including a logical channel having the highest priority among the one or more logical channel groups,
A 3-bit logical channel group identification information field, and a 5-bit buffer size field. 9. The method of claim 8,
The long-truncated BSR includes:
A logical channel group indication field, and a buffer size field,
The logical channel group indication field includes:
Wherein the buffer size field is composed of 8 bits of bitmap and indicates whether the buffer size field exists for each of eight logical channel groups. In a terminal transmitting a buffer status report (BSR)
A receiver for receiving allocation information on uplink resources from a base station;
Wherein a number of padding bits according to data transmission using the uplink resource is equal to or larger than a first value plus a size of a Short BSR and a size of the Short BSR subheader and less than a second value plus a size of a Long BSR and a size of the Long BSR subheader In addition,
A controller for determining whether there is available data for uplink transmission in at least one logical channel group (LCG) when the number of padding bits is equal to or greater than the first value and less than the second value; And
And a transmitter for transmitting a Short Truncated BSR or a Long Truncated BSR to the BS according to a result of comparison between the number of padding bits and the first value when there is available data for uplink transmission in the at least one logical channel group Included terminal. 14. The method of claim 13,
The transmitter may further comprise:
And transmitting the Short Truncated BSR when the number of the padding bits is equal to the first value,
And transmits the Long Truncated BSR when the number of padding bits exceeds the first value. 14. The method of claim 13,
The Short Truncated BSR includes:
And buffer size information for one logical channel group including a logical channel having the highest priority among the one or more logical channel groups,
A 3-bit logical channel group identification information field, and a 5-bit buffer size field. 14. The method of claim 13,
The long-truncated BSR includes:
A logical channel group indication field, and a buffer size field,
Wherein the logical channel group indication field indicates the presence or absence of a buffer size field for each logical channel group. 17. The method of claim 16,
The logical channel group indication field includes:
Wherein the buffer size field is composed of 8 bits of bitmap and indicates whether the buffer size field exists for each of eight logical channel groups. 17. The method of claim 16,
The buffer size field may comprise:
And index information which is composed of 8 bits for each logical channel group and is set according to buffer size information of each logical channel group,
Wherein the index information is mapped according to a range of buffer size information and is determined according to a preset table. 17. The method of claim 16,
The long-truncated BSR includes:
Buffer size information for one or more selected logical channel groups,
Wherein the one or more selected logical channel groups comprise:
And the logical channel group identification information is selected based on the ascending order of the logical channel group identification information when a plurality of logical channel groups including the logical channels having the same priority are present, Terminal. In a base station receiving a buffer status report (BSR)
A transmitter for transmitting allocation information on an uplink resource to a terminal;
Determined by the number of padding bits according to data transmission using the uplink resource when there is available data for uplink transmission in at least one logical channel group (LCG) of the UE, A receiver for receiving the BSR or the Long Truncated BSR; And
And a controller for checking available data for uplink transmission of one or more logical channel groups of the UE according to the Short Truncated BSR or the Long Truncated BSR.
21. The method of claim 20,
The Short Truncated BSR includes:
Wherein the number of padding bits is equal to or greater than a first value plus the size of the Short BSR and the size of the Short BSR subheader and less than a second value plus the size of the Long BSR and the size of the Long BSR subheader,
And when the number of padding bits is equal to the first value. 21. The method of claim 20,
The long-truncated BSR includes:
Wherein the number of padding bits is equal to or greater than a first value plus the size of the Short BSR and the size of the Short BSR subheader and less than a second value plus the size of the Long BSR and the size of the Long BSR subheader,
And when the number of padding bits exceeds the first value. 21. The method of claim 20,
The Short Truncated BSR includes:
And buffer size information for one logical channel group including a logical channel having the highest priority among the one or more logical channel groups,
A 3-bit logical channel group identification information field, and a 5-bit buffer size field. 21. The method of claim 20,
The long-truncated BSR includes:
A logical channel group indication field, and a buffer size field,
The logical channel group indication field includes:
Wherein the buffer size field is composed of 8 bit bits and indicates whether the buffer size field exists for each of eight logical channel groups.

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