KR100915604B1 - Method and apparatus for processing buffer status information using padding region - Google Patents

Abstract

In a method and apparatus for processing a Buffer Status Report (BSR), when BSR triggering is performed, the size of necessary subheaders is considered along with the BSR size. Checking whether there is padding space in the configured MAC PDU, comparing the number of padding bits to the combined size of a buffer status report (BSR) and its associated sub-header, and the number of padding bits in the buffer If the status report (BSR) and the associated subheader (sub-header) is larger than the combined size, triggering the buffer status report (BSR) is performed. In addition, adding the BSR and its subheaders to the MAC PDU, and setting a logical channel identification (LCID) to the subheader to indicate that the BSR has been triggered by padding and the BSR has been added. Can be. In this way, subheaders may be added or inserted into the MAC PDU, Transport Block (TB), or other data unit.

Buffer status reporting (BSR), buffer triggering, MAC subheader, LCID

Description

Method and apparatus for processing buffer status information using padding space {METHOD AND APPARATUS FOR PROCESSING BUFFER STATUS INFORMATION USING PADDING REGION}

The present invention relates to a method and apparatus for processing buffer status report (BSR).

In the prior art, the report on the buffer status information was performed, but the radio resources were unnecessarily wasted. Therefore, the prior art did not fully consider this point and did not provide a suitable solution.

The present inventors have recognized the disadvantages of this prior art, and based on this, they have invented several features described below and have improved the handling of buffer status information to improve the protocol data unit (PDU) (or transport block (TB) transport). When forming a block or other type of data unit), buffer status information is added to an available portion of the PDU, resulting in more efficient use of radio resources.

In a method and apparatus for processing a Buffer Status Report (BSR), when BSR triggering is performed, the size of necessary subheaders is considered along with the BSR size. In this way, subheaders may be added or inserted into the MAC PDU, Transport Block (TB), or other data unit.

In the effect of the present invention, when the terminal configures the MAC PDU, if the space is left in the MAC PDU, by presenting a method that can be effectively utilized, bringing the effect of increasing the utilization efficiency of radio resources.

The various features and concepts described herein are applicable and applicable to various user equipments (mobile terminals, cellular phones, wireless communications devices, etc.) and / or network objects that are suitably configured to process buffer status information / reporting (BSR). Do.

In addition, the present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. . Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Inventive concepts and features for buffer status report (BSR) processing are described based on the Long Term Evolution (LTE) system or other so-called 4G communication system advanced in current 3GPP technology. However, the specifics are not intended to limit the features described herein and are applicable to various mobile and / or wireless communication systems and methods.

Hereinafter, the term “terminal” refers to various types of user devices, for example, mobile communication terminals, user equipments (UEs), mobile devices (MEs), and various devices supporting radio technologies.

The present invention relates to a method for transmitting and receiving data between a base station and a terminal in a long term evolution system (LTE). In particular, in a MAC entity constituting a MAC PDU by receiving data from each logical channel, a MAC PDU (or transport block) The present invention relates to a method of preventing unnecessary waste of radio resources by allowing the terminal to effectively send buffer status information when padding space occurs in another kind of data unit.

1 is a diagram illustrating a network structure of an evolved universal mobile telecommunications system (E-UMTS) which is a mobile communication system. The E-UMTS system is an evolution from the existing UMTS system and is currently undergoing basic standardization in 3GPP. The E-UMTS system may be referred to as a Long Term Evolution (LTE) system.

E-UMTS network 100 can be largely divided into E-UTRAN (110) and CN. The E-UTRAN is a serving gateway (122,124) (Serving Gateway) connected to an external network located at the terminal 112 (User Equipment; abbreviated as UE) and the base station 114, 116, 118 (hereinafter abbreviated as eNode B), the end of the network; (Hereinafter abbreviated to S-GW) and mobility management entities 122 and 124 (Mobility Management Entity (hereinafter, abbreviated as MME)) that manage mobility of terminals. One or more cells may exist in one eNode B.

2 and 3 illustrate a structure of a radio interface protocol between a terminal and a base station based on the 3GPP radio access network standard. The air interface protocol is composed of a physical layer, a data link layer, and a network layer horizontally, and a user plane and control for data information transmission vertically. It is divided into a control plane for signal transmission. The protocol layers are based on the lower three layers of the Open System Interconnection (OSI) reference model, which is well known in communication systems. L1 (Layer 1), L2 (Layer 2), and L3 (Layer 3) It can be divided into.

Hereinafter, the control plane radio protocol of FIG. 2 and the user plane radio protocol of FIG. 3 will be described.

The physical layers 225 to 245 and 325 to 345, which are the first layers, provide an information transfer service to a higher layer by using a physical channel. The physical layer is connected to the upper medium access control layer (224-244, 324-344) through a transport channel, and the medium access control layer and the physical layer The data moves. Then, data is moved between different physical layers, that is, between physical layers of a transmitting side and a receiving side through physical channels.

Medium access control (hereinafter referred to as MAC) of the second layer provides a service to a radio link control layer 223-243 and 323-343, which is a higher layer, through a logical channel. . The radio link control layer (hereinafter referred to as RLC) layer of the second layer supports reliable data transmission. The PDCP (Packet Data Convergence Protocol) layer 322-342 of the second layer contains relatively large and unnecessary control information for efficient transmission in a wireless bandwidth having a small bandwidth when transmitting an IP packet such as IPv4 or IPv6. Header Compression, which reduces the IP packet header size. The PDCP layer is also used to perform encryption of C-plane data, for example RRC messages. PDCP also performs encryption of U-plane data.

The radio resource control layer (222-242) located at the top of the third layer is defined only in the control plane, and the configuration of radio bearers (abbreviated as RB) is configured. It is responsible for the control of logical channels, transport channels, and physical channels in connection with reconfiguration and release. In this case, RB means a service provided by the second layer for data transmission between the terminal and the E-UTRAN.

The following is a detailed description of the RACH (Random Access Channel). The RACH channel is used for transmitting a short length of data upward. In particular, the RACH channel is used when there is a signaling message or user data to be transmitted upward by a terminal that has not been allocated a dedicated radio resource. Or, it may be used when the base station instructs the terminal to perform the RACH process.

As mentioned above, two axes constituting the E-UTRAN are a base station and a terminal. The radio resource in one cell is composed of an uplink radio resource and a downlink radio resource. The base station is responsible for allocating and controlling uplink and downlink radio resources of the cell. That is, the base station determines which radio resource is used by which terminal at any moment. For example, the base station may determine that after 3.2 seconds, the frequency 100Mhz to 101Mhz is allocated to user 1 for downlink data transmission for 0.2 second. After the base station makes this determination, the base station notifies the corresponding terminal of the fact so that the terminal receives the downlink data. Similarly, the base station determines when and which terminal to use to transmit data upwards using what radio resources, and the base station informs the terminal of this determination, so that the terminal transmits data using the radio resources during the time. Do it.

Unlike the related art, the base station dynamically manages radio resources to enable efficient use of radio resources. The prior art allows one terminal to continue using one radio resource while the call is connected. This is particularly unreasonable considering that many services in recent years are based on IP packets. This is because most packet services do not generate packets steadily during the connection time of the call, but there are many intervals in which nothing is transmitted during the call. In this case, it is inefficient to continuously allocate radio resources to one UE. In order to solve this problem, the E-UTRAN system uses a method of allocating radio resources to the terminal in the same manner as above only when there is service data when the terminal is needed.

More specifically, in the LTE system, in order to use radio resources efficiently, the base station must know what data and how much to transmit to each user. In the case of downlink data, this downlink data is transferred from the access gateway to the base station. Therefore, the base station knows how much data should be transmitted to the downlink to each user. On the contrary, in the case of uplink data, the base station cannot know how much uplink radio resources each terminal needs unless the terminal directly informs the base station of information about data to be transmitted on the uplink. Therefore, in order for the base station to properly allocate uplink radio resources to the terminal, each terminal should provide the base station with information necessary for the base station to schedule radio resources.

To this end, the terminal informs the base station when there is data to be transmitted, and the base station transmits a radio resource allocation message to the terminal based on this information.

In the above process, that is, when the terminal informs the base station when there is data to be transmitted, the terminal informs the base station of the amount of data accumulated in its buffer. This is called Buffer Status Report (BSR).

However, the buffer status information is generated in the form of MAC Control Element and included in the MAC PDU and transmitted from the terminal to the base station. That is, uplink radio resources are required to transmit the buffer status report (BSR). This means that uplink radio resource allocation request information for transmitting buffer status information should be transmitted. When the buffer state information is generated, if there is an allocated uplink radio resource, the terminal immediately transmits the buffer state information by using the uplink radio resource. The process of transmitting the buffer state information to the base station by the terminal is called a buffer state information process (BSR procedure).

Hereinafter, the MAC PDU structure will be described with reference to FIGS. 4 to 8 showing various examples of the MAC PDU format used by the MAC object (224, 244 of FIG. 2 or 324, 344 of FIG. 2).

4 shows the form of a MAC PDU used in a MAC entity.

4 shows a format of a PDU used in a MAC entity. In the figure, the LCID indicates whether an associated MAC SDU or a MAC Control Element (CE) is used. Also, if an associated MAC SDU is an MAC SDU, the MAC SDU corresponds to a logical channel. The L field informs the size of the MAC SDU for the MAC SDU. The E field indicates whether another MAC SubHeader exists. In the above process, if the size of the corresponding MAC SDU or MAC Control Element is less than or equal to 127, 7-bit L field is used, and in other cases, 15-bit L field is used. If the MAC SDU included in the MAC PDU is the last of the data fields included in the MAC PDU, the MAC SubHeader associated with the MAC PDU is used. Alternatively, for a fixed MAC control element, the MAC SubHeader of the form shown in Figure 6 is used. Otherwise, the MAC SubHeader of the type shown in FIG. 5 is used.

7 and 8 illustrate the format of the BSR Report. Depending on the number of logical channel groups with data and the amount of space available in the MAC PDU, short BSR or Long BSR is used. Where the short BSR and the long BSR refer to their BSR 'relative length. Accordingly, other various terms describing this kind of BSR may be used. For example, a short BSR may be referred to as a shortened or shortened BSR, and a long BSR may be called an extended or elongated BSR.

The following is a description of each field used in FIGS. 4 to 6.

LCID: This tells which logical channel the MAC SDU is or what information the MAC Control Element (MAC) contains.

E: This indicates whether there is another MAC SubHeader behind this MAC SubHeader.

F: It tells the length of the following L field.

R: Reserved bit, unused bit.

The following is information about values used for the LCID.

Hereinafter, a method of configuring a MAC PDU by a MAC entity will be described.

When multiple RBs are transmitted multiplexed to one transport channel, the LTE terminal determines the amount of data transmitted for each RB by using the following rules for a given radio resource for every transmission in the MAC layer. do.

1. First, the amount of data to be transmitted is determined in descending order of each logical channel priority (LCP) for the multiplexed RBs, and a MAC PDU is formed using the data of the logical channel according to the determined amount of data. do.

2. If there are remaining radio resources, determine the amount of transmitted data in descending order of each LCP for the multiplexed RBs again.

LCP is currently discussed in the range of 1 to 8, where 1 is the highest and 8 is the lowest. In addition, if there is a MAC CE (Control Element) to be sent in the process, the MAC CE is included in the MAC PDU first.

According to the prior art, the UE triggers the BSR process in at least one case as follows.

1) When there is no data in all buffers, and when new data arrives in a buffer, (Regular BSR)

2) Data arrives in an empty buffer, and the priority of the logical channel associated with the buffer is higher than the logical channel that previously had data in the buffer (Regular BSR).

3) If the cell has changed (Regular BSR)

4) When a certain time has passed since the last BSR was sent (Periodic BSR)

5) If there is remaining space in the configured MAC PDU (Padding BSR)

In the above triggers, when the BSR is triggered due to the last case, the BSR is called a padding BSR in this case. The terminal configures the MAC PDU according to the amount of radio resources allocated from the base station, that is, the size of the MAC PDU. In this case, the MAC entity of the UE sequentially includes data stored in a buffer of the logical channel in the MAC PDU for each logical channel set to the UE, and includes all data stored in each logical channel in the MAC PDU. If space is left, the BSR process is triggered, and the padding BSR triggered in this process is included in the MAC PDU to configure the MAC PDU and then transmitted to the base station.

However, according to the related art, the BSR generated due to the padding is located at the end of the MAC PDU. That is, after the MAC entity of the terminal configures the MAC PDU using data of the respective logical channels, if space remains in the MAC PDU, the BSR is additionally inserted after the configured portion. That is, FIG. 9 can be considered.

In FIG. 9, it is assumed that a terminal has been allocated radio resources for configuring a MAC PDU having an X + N byte size from a base station. In this case, the MAC entity will begin to populate the MAC PDU based on the data stored in each logical channel. Part (a) of the above figure shows that padding occurs when MAC entity configures MAC PDU using all data stored in its buffer. If the size of the padding is larger than the size of the BSR, the MAC entity adds the BSR to the portion.

In this case, as shown in FIG. 9, since the padding BSR is not informed due to the padding, the receiving side receiving the MAC PDU cannot effectively use the BSR information. That is, since the receiver cannot know which of Figs. 9A and 9B has been received, even if the BSR is included in the MAC PDU, the base station cannot effectively allocate radio resources using the BSR information.

In addition, in some cases, in order to send a padding BSR, the amount of user data included in the MAC PDU is reduced.

10 illustrates a case in which the UE is instructed to configure a MAC PDU having an L + M + 3 byte size. REMAINING SPACE is a padding space in the figure above and 2BYTE as shown. In this case, since the size of the SHORT BSR is 1, the terminal determines that the SHORT BSR can fit in the space, and triggers the PADDING BSR. In this case, a problem arises when the MAC entity attempts to include the SHORT PADDING BSR. For example, in the figure above, the MAC SUBHEADER for RLC PDU N does not contain the L field. However, if PADDING BSR is entered in the process, the RLC PDU N is no longer the last element included in the MAC PDU. Therefore, according to the prior art, the MAC SUBHEADER should include the L field for the MAC SDU that is not the last element. Therefore, the following error occurs when the PADDING BSR is excessively included in the above process.

That is, as shown in Fig. 11, since 1 byte of the remaining 2 bytes is used for the padding BSR, only 1 byte can be additionally used by the MAC SubHeader. However, if the RLC PDU N in the figure requires an L field of 2 bytes, this is an error situation. In this case, some RLC PDUs must be reduced in size by 1 byte in order to form a proper MAC SubHeader.

The present invention proposes a method in which the MAC entity effectively includes the Padding BSR in the MAC PDU and transmits it when the Padding BSR is triggered. Various embodiments will be described below.

Example 1

The present invention proposes to place the Padding BSR at a position other than the last part of the MAC PDU. When the Padding BSR is triggered, it is proposed to place the Padding BSR immediately before the last one among other MAC SDUs or MAC CEs of the MAC PDU. Accordingly, the MAC SDUs, MAC CEs, and MAC SubHeaders related to Padding BSR are also arranged in the same order. When the padding BSR is triggered, it is suggested to place the padding BSR before other MAC SDUs included in the MAC PDU. Accordingly, MAC SubHeaders related to the Padding BSR are also arranged in the same order. If the Padding BSR is triggered, it is suggested to place the Padding BSR after other MAC SDUs of the MAC PDU. Accordingly, MAC SubHeaders related to the Padding BSR are also arranged in the same order.

In constructing a MAC PDU, after filling the MAC PDU with other MAC CEs or MAC SDUs and associated MAC SubHeaders, the MAC PDU is equal to the size of the Short BSR or Long BSR plus the size of its SubHeader. If the space of size remains, the short BSR or long BSR is included in the MAC PDU. Preferably, in this process, the MAC Padding BSR is located before the MAC SDU or MAC CEs included in the MAC PDU. Preferably, in this process, the MAC SubHeader related to the MAC Padding BSR is included first among the MAC SubHeaders included in the MAC PDU.

The present invention proposes to consider the size of MAC SubHeader when the MAC entity triggers the Padding BSR. That is, in constructing a MAC PDU, the MAC entity also considers the size of the BSR and the size of its SubHeader in considering whether or not there is padding space in the MAC PDU. For example, the size of the Short BSR is 1 byte, but considering the size of its SubHeader, 1 byte, the Padding BSR is triggered only when the space left in the MAC PDU is 2 bytes or more, in this case, the Short BSR. In this case, the PADDING BSR is triggered only when SubHeaders of other MAC SDUs and MAC CEs can be normally configured. In this case, the normal configuration includes the MAC SubHeader without the F / L field for the MAC CE that does not need the L field, and the F / L field for the remaining MAC SDUs except the MAC CE or the last MAC SDU for which the L field is required. Refers to including the MAC SubHeader with no F / L field for the last MAC SDU.

In the above process, after the MAC PDU is configured, after the space remains and the Padding BSR is triggered, if the BSR is included in the MAC PDU, the BSR is regarded as a regular BSR. That is, the padding BSR is treated like the regular BSR. That is, in this case, the PADDING BSR is subject to the constraint of the location configuration such as the REGULAR BSR.

In the above process, when the Padding BSR is triggered due to the padding, in particular, when the Short BSR is included in the MAC PDU due to the Padding BSR, the short BSR is among the logical channels configured in the terminal, among the channels having data in the buffer, Contains buffer information of the logical channel group associated with the logical channel having the highest priority.

Example 2

According to the present invention, the receiving side of the MAC PDU easily checks whether the BSR is included in the MAC PDU, especially if the BSR is included in the MAC PDU due to padding. For this purpose, it is suggested that the BSR is triggered due to the padding and included in the MAC PDU. Specifically, it is proposed to indicate that BSR is included using MAC SUBHEADER.

In FIG. 12A, when the padding is included in the MAC PDU, the receiving side can know whether the padding BSR is included based on the size of the padding. In Figure (b), even if the BSR is included in the MAC PDU due to padding, the existence of the BSR is directly indicated so that the MAC PDU includes the MAC SubHeader set to the LCID field related to the included BSR.

In another manner of the present invention, the receiving side considers the BSR as a padding BSR when the BSR is included in the MAC PDU and when there is padding in the MAC PDU.

In the above process, when the padding BSR is triggered due to the padding, and because of this, when the BSR is included in the MAC PDU, an LCID different from the LCID allocated to indicate the short BSR or the long BSR may be designated to indicate this. . That is, when the Padding BSR is triggered due to padding, and because of this, when the BSR is included in the MAC PDU, the UE sets and transmits an LCID field with the LCID in the MAC Subheader associated with the BSR.

Example 3

Referring to Fig. 13 with pictures (a), (b) and (c), in constructing a MAC PDU, the transmitting MAC entity fills the MAC PDUs with data and MAC control elements received from each logical channel. Next, a method of using the case where 2 bytes of space is left in the MAC PDU will be presented. The following shows various methods of use.

According to the present invention, in constructing a MAC PDU, the transmitting MAC entity fills MAC PDUs with data and MAC control elements from each logical channel, and then pads a header when 2 bytes of space remain in the MAC PDU. That is, the remaining space is filled by using a method including a plurality of 1-byte padding headers.

According to the present invention, in constructing a MAC PDU, the transmitting MAC entity fills MAC PDUs with data and MAC control elements from each logical channel, and then the last MAC SubHeader when 2 bytes of space remain in the MAC PDU. Fill the 2 bytes with the L field.

In the present invention, in constructing a MAC PDU, the transmitting MAC entity fills MAC PDUs with data and MAC control elements from each logical channel, and then pads a BSR when 2 bytes of space remain in the MAC PDU. That is, the remaining space is filled by using a method including MAC SUBHEADER for 1 byte BSR and SHORT BSR for 1 BYTE.

The above example also applies when 4 BYTE (or other number of bytes) is left in the MAC PDU instead of 2BYTE.

Example 4

In addition, the present invention proposes to include a TAC command (Timing Alignment Command) in the MAC PDU when the base station configures the MAC PDU and transmits the MAC PDU to the terminal after the padding space is generated. The TAC command is used by the terminal to adjust the uplink transmission timing.

For example, if a base station configures a MAC PDU and 2 bytes remain in the MAC PDU, 1 byte of the 2 bytes should be allocated for the subheader of the TAC command, and the remaining 1 byte should be adjusted in the upward direction by the TAC command. Allocate for timing information.

Alternatively, even if only 1 byte of padding space remains, the base station does not include the associated MAC SubHeader and transmits the TAC command in the MAC PDU.

Example 5

As a result, the present invention intends to prevent the Padding BSR from triggering when the Padding BSR cannot be included in the MAC PDU by providing a more accurate criterion in determining that there is a Padding space and triggering the Padding BSR.

Therefore, in the present invention, when the terminal configures the MAC PDU using MAC CEs and MAC SDUs, the terminal obtains the remaining free space, that is, the size of the padding byte, the size of the padding byte is MAC in the size of the MAC PDU This is obtained by subtracting the size of SDUs, MAC CEs, and MAC SubHeaders associated with them. In this calculation, for the last element included in the MAC PDU, that is, the last MAC SDU, the UE assumes that the L field is included in the MAC SubHeader related to the MAC SDU. If the last element is a MAC CE and if the MAC CE has a variable size, for the MAC CE, the UE assumes that the MAC SubHeader associated with the MAC CE contains an L field, i.e., the last element of the MAC PDU. Assuming that the MAC SubHeader for "R / R / E / LCID / F / L", the size of the padding byte in the MAC PDU is calculated. The padding BSR is triggered only when the size of the padding byte is equal to or larger than the sum of the size of the BSR and the size of the MAC SubHeader associated with the padding byte.

That is, when obtaining the number of padding bytes, all MAC SDUs included in the MAC PDU are calculated by including the F / L field in the related MAC SubHeader. In this case, even for MACCEs of variable size, the F / L field is included in the SubHeader associated with the MAC CE. The padding BSR is triggered only when the number of padding bytes is equal to or larger than the sum of the BSR and the MAC SubHeader associated with the BSR.

Example 6

Referring to Fig. 14 with Figs. (A) and (b) and Fig. 15 with Figs. (A), (b) and (c), in constructing a MAC PDU, the transmitting MAC entity may determine each MAC PDU. After filling with MAC control elements and data from a logical channel, if there are two bytes of space left in the MAC PDU, in particular, if the short BSR is already included in the MAC PDU, the short BSR is converted into a Long BSR. Offer to replace. That is, the Long BSR is included in the MAC PDU instead of the short BSR. This is illustrated in FIG. 14.

That is, according to the present invention, in configuring a MAC PDU, the transmitting MAC entity fills MAC PDUs with data and MAC control elements from each logical channel, and then, if 4 bytes of space remain in the MAC PDU, This is used for Padding BSR, especially Long BSR. In this case, 4 byte means 1 byte MAC Subheader, 1 byte Short BSR and 2 byte Padding byte.

Preferably, in the present invention, in constructing a MAC PDU, the transmitting MAC entity fills MAC PDUs with data and MAC control elements from each logical channel, and then the BSR is already included in the MAC PDU. If there is space left in the MAC PDU, it is proposed to include another BSR.

Preferably, in the present invention, in constructing a MAC PDU, the transmitting MAC entity fills MAC PDUs with data and MAC control elements from each logical channel, and then the BSR is already included in the MAC PDU. In this case, the padding BSR is not triggered if there is space left.

Preferably, in the present invention, in constructing a MAC PDU, the transmitting MAC entity fills the MAC PDUs with data and MAC control elements from each logical channel and then, if space is left, is also already Periodic BSR or Regular. When the BSR is triggered, it includes only the largest padding BSR that can be included in the remaining space and the larger of the already triggered BSRs.

Preferably, in the present invention, in constructing a MAC PDU, the transmitting MAC entity fills the MAC PDUs with data and MAC control elements from each logical channel, and when space is left, it is also already Periodic BSR or Regular. If the BSR is triggered, the Padding BSR is not triggered.

In the effect of the present invention, when the terminal configures the MAC PDU, if the space is left in the MAC PDU, by presenting a method that can be effectively utilized, bringing the effect of increasing the utilization efficiency of radio resources.

Further details regarding the concept and features of the present invention are described below.

Remark # 1

The padding BSR may be included elsewhere or in position before the last MAC subheaders. That is, if the TB is filled with a subheader and associated MAC SDUs and other MAC control elements, then a 2 byte short BSR is included if 2 bytes of padding remain. For example, the first subheader can be a short BSR if padding can be removed correctly.

That is, if the padding is 2 bytes after filling the transport block (TB) with subheader and associated MAC SDUs and other MAC control elements, the last subheader of the MAC SDU may include an L field of 2 bytes. Use an F field that represents a long L field and a 15 bit L field. When decoding each MAC subheader, when the sum of the size of the MAC control element or associated MAC SDUs related to the size of the subheaders is equal to the size of the transport block (except trailing 1 to 7 bits), the receiving MAC entity is It is assumed that there are no more subheads. This is not considered an error situation. That is, the L field may be included in the last MAC subheader if the transport block can be exactly fit without the padding byte / LCID.

Remark # 2

Padding occurs at the end of a MAC PDU, except when one or two byte padding is required but padding cannot be achieved at the end of the MAC PDU. If one or two byte padding is required but cannot be padded at the end of the MAC PDU, before the first MAC PDU corresponding to the MAC PDU, or, if no such subheader exists, the last MAC PDU sub corresponding to the MAC control element. One or two MAC PDU subheaders corresponding to the padding are inserted before the header.

For FDD, if the size of the data and header is equal to or smaller than 24 from the size of the transport block of the E-TFC selected by the UE, either by supporting quantization or by triggering scheduling information, the DDI value [111111] will be added to the end of the MAC-e header, and the scheduling information will be included in this MAC-e PDU. The DDI value [111111] specifies that scheduling information is included in this MAC-e PDU. On the other hand,. If the size of the data and the header is smaller than or equal to 18 minus the transport block size of the E-TFC selected by the UE, scheduling information is concatenated in this MAC-e PDU. In other cases, there is no space for other MAC-es PDUs or scheduling information and there is no need to reserve space in the transport block for additional DDI fields.

That is, in the case of HSUPA, in order to determine what to include in the MAC TB and when to stop filling, the sender continuously compares the combined size of the MAC header and the MAC data with the available transport block size. Thus, in some cases, scheduling information is added without a field indicating whether this is the case. Therefore, certain header fields such as DDI can be omitted and increase efficiency.

However, the current LTE MAC standard does not specify this behavior. Therefore, it is questionable whether HSUPA operation is prohibited. This is shown in FIG.

In Figure (a), the remaining two bytes are used by adding two padding subheaders. In Figure (b), two bytes are filled with F and L fields. Therefore, these F and L fields are also included in the last subheader. This is similar in HSUPA. That is, by comparing the total sum of the data fields in the subheaders with the size of the transport block, it can be seen that there is no padding at the receiving side. In Figure (c), two bytes are replaced by a short BSR. The short BSR is not an empty BSR. As shown in Fig. 16, a useful situation (c) is shown.

According to FIG. 16, whether or not padding LCID does not distinguish whether or not data is still present in the terminal buffer. In order to increase the efficiency of the eNB scheduler, the scheme of FIG. 13 (c) is better than that of (a). That is, it would be more useful to be used for short BSR without wasting 2 bytes due to padding.

4 to 6, the MAC PDUs (DL-SCH and UL-SCH) will be described.

The configuration of a MAC PDU includes a MAC header, zero or more MAC Service Data Units (MAC SDUs), zero or more MAC control elements, and optionally padding. MAC header and MAC SDUs have a variable length. There are one or more MAC PDU subheaders in the MAC PDU header, each subheader corresponding to a MAC SDU, MAC control element or padding. In some embodiments, MAC PDU subheaders for padding should not occur more than once in a MAC PDU.

The MAC PDU subheader may consist of six header fields (R / R / E / LCID / F / L), except for the last subheader of the MAC PDU and MAC control elements of fixed size. The last subheader of the MAC PDU and the subheaders of the fixed size MAC control elements consist of only four header fields (R / R / E / LCID). Therefore, the MAC PDU subheader corresponding to the padding is composed of four header fields (R / R / E / LCID).

MAC PDU subheaders have the same order as the corresponding MAC SDUs, MAC control elements and padding. MAC control elements (except padding BSR) are placed before any MAC SDU. The padding BSR is at the end of the MAC PDU. Padding is at the end of a MAC PDU except when one byte is required but padding is not sufficient at the end of the MAC PDU. When one byte is required but padding is not sufficient at the end of the MAC PDU, the MAC PDU subheader corresponding to the padding is inserted before the first MAC PDU subheader corresponding to the MAC SDU or, if no such subheader is present, corresponds to the MAC control element. It is located before the last MAC PDU. When two bytes remain after filling the MAC PDU with MAC SDUs or MAC control elements (except BSR), the short BSR is included.

In some embodiments, at most one MAC PDU is sent for one TB and one UE. In addition, according to the physical layer classification, one or two TBs are transmitted for one TB and one UE.

Whether this MAC PDU corresponds only to DL / UL SCH or other transport channels is FFS.

Note # 3

If the remaining space in the MAC PDU is equal to or larger than the size of the BSR, then the padding BSR is included. If uplink (UL) resources are allocated and the number of padding bits is greater than the BSR MAC control element, then this BSR is called a padding BSR. As to how to represent this padding BSR, consider the following: The MAC control elements (except the padding BSR) are always located before any MAC SDU. However, padding occurs at the end of the MAC PDU, unless it can be realized by padding at the end of the MAC PDU. Both padding BSR and padding may occur at the end of the MAC PDU. However, the BSR LCID is used to directly inform the padding BSR, indirectly to the padding LCID, the padding BSR comes after the padding, the padding comes after the padding BSR, and the like.

How to announce padding BSR (4 suggestions)

Figure 17 shows two implementations of how to tell whether a padded BSR is present (see Figures (a) and (b)).

In Figure (a), depending on the size of the padding interval, we include either short or long BSRs without corresponding subheaders. In Figure (a), the BSR can be included if the padding size is 2 bytes or larger. In this manner, after filling the MAC PDU with other subheaders or MAC SDU / CE, if 3 bytes remain, the BSR may be included.

In Figure (b), the last two MAC subheaders are the BSR subheader and the padding subheader, and the padding BSR is advertised directly. In this scheme (b), after filling the MAC PDU with other subheaders or MAC SDU / CE, if 4 bytes remain, the BSR may be included.

In other words, the difference between schemes (a) and (b) is the minimum size of bytes remaining to be included in the BSR.

suggestion 1

Determine whether to inform padding BSR directly or indirectly, and consider the order of padding BSR and padding.

FIG. 17 illustrates two implementations of padding BSR for the direct notification scheme of FIG. 12 (a), both of which may be used. It will be appreciated that in Figure 17 the BSR can be located before and after the bytes used for padding.

FIG. 18 shows two implementations of the padding BSR in the case of the direct notification scheme of FIG. 12 (b), both of which may use the E field. Here, if the E field indicates another MAC subheader, the receiving side can know what follows after decoding the next byte. However, in the scheme (b), if the BSR LCID is detected after the padding LCID, the MAC receiver of the eNB may immediately decode the last bytes to know the buffer state of the terminal. On the other hand, in the scheme (a), upon detection of the BSR LCID, the MAC receiver of the eNB must first calculate the starting position of the BSR before decoding the first byte of the BSR.

Proposal 2

Determines whether the padding BSR in the MAC PDU will be last or the padding will be last.

Proposal 3

If the MAC PDU is filled with MAC SDUs or MAC CEs (except BSR) and 2 bytes remain, it should be used for short BSR delivery.

On the other hand, if the BSR is already included in the MAC PDU, if there are 2 bytes left, the case of FIG. 19 (2 bytes remaining after including the short BSR) and FIG. 20 (2 bytes remaining after including the long BSR, direct padding BSR notification) are shown. Can be considered

Fig. 19 (a) shows a case where two bytes remain when a short BSR is already included in a MAC PDU. This means that after filling only data from each logical channel, the MAC PDU had 4 bytes left in the first place. That is, after filling the MAC PDU with RLC PDUs, 4 bytes remained before including the short BSR. Regardless of whether there is additional data in the RLC objects, 4 bytes were originally padding bytes. If so, the long BSR should have been added instead of the short BSR. That is, you should use (b) instead of (a).

Fig. 20A shows the case where two bytes remain when a long BSR is included. This means that after filling the MAC PDU with data from each logical channel, there are still original I6 bytes. That is, it means that 6 bytes are available after filling the MAC PDU only with RLC PDUs from the upper layer. There are three cases.

1. If there is no data left in all RLC objects, the 6 bytes were the original padding bytes, and the BSR would have been canceled or a normal padding BSR would have been included. In this case, if direct instructions are used for the padding BSR, instead of figure (a) of Fig. 4, figures (b) and (c) occur. If an indirect indication is used for the padding BSR, instead of Figure (a) of Figure 5, Figures (b) and (c) occur.

2. If there was one logical channel with data after filling the MAC PDU, a short BSR would have been triggered and the remaining 4 bytes would have been used to contain data for that logical channel.

3. If there was more than one logical channel with data after filling the MAC PDU, the long BSR would have been triggered. This situation is strange, if direct instructions are used for the padding BSR, Figures (b) and (c) of Figure 20. Is generated, and Figures (b) and (c) of Fig. 21 are generated if the indirect instruction is used for the padding BSR (which is the case when two bytes remain after the long BSR is included).

Thus, the case of a two byte padding subheader may not be very obvious and is not always useful. The current MAC structure can avoid the use of 2-byte padding and the 2-byte padding subheader does not need to exist.

Proposal 4

The use of 2-byte padding subheaders in MAC headers should be avoided.

Note # 4

For the network, certain concepts of the present invention can be described as follows:

The eNB forms the MAC PDU using the data and MAC control elements available in the RLC / PDCP buffers for one UE.

After filling the MAC PDU with MAC SDUs / MAC CEs:

If 2 bytes remain after filling the MAC PDU,

-The eNB includes a Timing Alignment Command (TA CMD) in the MAC PDU instead of the 2 bytes.

--- In this case, one byte is used to contain the subheader of the TA CMD,

---- One byte is used to contain the value of the actual timing indication.

If two or more bytes remain after filling the MAC PDU,

-eNB includes TA CMD in MAC PDU and replaces at least two bytes.

In this case, one byte is used to contain the subheader of the TA CMD.

---- 1 byte is used to contain the value of the actual timing indication,

----- And at least 1 byte is used as subheader for padding.

Or, if two or more bytes remain after filling the MAC PDU,

-eNB includes TA CMD in MAC PDU and replaces at least two bytes.

In this case, one byte is used to contain the subheader of the TA CMD,

---- And 1 byte is used as subheader for padding,

----- And other bytes are used as padding.

--- Or, one byte of padding is replaced with a TA CMD.

For the terminal, certain concepts of the invention may be described as follows:

The UE decodes / recombines the received MAC PDU into MAC SDUs and / or MAC CEs.

The UE decodes each MAC subheader and associated MAC SDUs / CEs

The UE calculates the sum of the sizes of the subheaders and MAC SDUs / CEs

-UE compares the sum of these sizes with the MAC PDU size

If padding is indicated and the size of the padding (except for the padding subheader) is greater than or equal to 1 byte,

-UE considers TA CMD included in the padding part.

Note # 5

On the upside, according to the current MAC standard, the UE will include a BSR if the padding space allows inclusion of a BSR. Given that 2 bytes are needed to include the short BSR, whenever the remaining padding space is 2 bytes, we will include the BSR in the MAC PDU.

In Fig. 22, two bytes are sufficient for inclusion of a short BSR, so that the situation in Fig. (A) will not occur. According to the spirit of the current standard, the terminal will have to send in the form (b) of FIG.

Thus, the following special processing for 2-byte padding is not necessary.

Padding occurs at the end of a MAC PDU, except when one or two byte padding is required but not at the end of the MAC PDU. If one or two byte padding is required but not at the end of the MAC PDU, one or two MAC PDU subheaders corresponding to the padding are included before the first MAC PDU subheader corresponding to the MAC SDU; Or if such subheaders do not exist, they are included before the last MAC PDU subheader corresponding to the MAC control element.

Since the BSR in Fig. 22B is included because of the padding space, it can be referred to as a padding BSR. Since the BSR is not located at the end of the MAC PDU, it may be argued that this does not match the definition of the current padding, but the padding BSR need not be the last element of the MAC PDU. This padding BSR is also referred to as a direct LCID. Thus, the padding BSR can be anywhere in the MAC PDU.

For downward, there is no need for BSR and the situation is different from upward. Therefore, downward processing requires special processing for 2-byte padding. Since the size of the TA CMD is two bytes, it can be considered that the TA CMD can be included whenever two bytes remain in the MAC PDU. It is desirable to send more TA CMDs because it can keep the UE in sync longer, but this unnecessarily limits the operation of the eNB.

As a further review, for the sake of safety, we have considered the case where 2 bytes remain for a MAC PDU already containing BSR. . This is shown in Figure 23 (short BSR) and Figure 24 (long BSR).

That is, if 2 bytes remain for a PDU that already contains a short BSR, it means that 4 bytes are available for BSR. If so, the short BSR will be replaced by the long BSR. Thus, figure (b) will be generated instead of figure (a) of FIG.

That is, if 2 bytes remain for a PDU that already contains a long BSR, it means that 6 bytes are available for the BSR. If so, 4 bytes are used for the long BSR and the remaining 2 bytes can be used for the L field or padding LCID for the last MAC SDU. Therefore, it would be necessary to use figure (b) or (c) instead of figure (a) of FIG.

Note # 6

The features of the present invention may be described as follows:

On the padded BSR:

If the number of padding bits is equal to or greater than the size of the short BSR and less than the size of the long BSR, report the short BSR of the LCG of the highest priority logical channel with buffered data;

Otherwise, if the number of padding bits is equal to or greater than the size of the long BSR, report the long BSR.

Location of Padded BSR

The BSR in FIG. 22 (b) is included because of the padding space and can be referred to as a padding BSR. However, because the BSR is not located at the end of the MAC PDU, it may be considered to be contrary to the current BSR definition. However, the padding BSR need not be the last element of the MAC PDU. Moreover, the padding BSR is indicated by the direct LCID. Thus, the padded BSR can be located anywhere within the MAC PDU.

Figure 25 shows an example where there are 2 bytes of space left in the TB (the padding BSR is the last element).

If the padding BSR is defined as the last element except for padding in the MAC PDU, the figure (b) of FIG. 25 should be used.

In Figure 25 (b), there is no L field in the second MAC subheader. However, since it is not the last subheader in the MAC PDU, figure (b) of Figure 25 may not be accurate.

Obviously, it is better to have BSR than no BSR. Therefore, the figure (b) of FIG. 22 should be used instead of the figure (a) or (b) of FIG. Therefore, the BSR location in the MAC PDU must not be restricted.

MAC control elements (except padding BSR) are placed before any MAC SDU. Padding BSR is generated at the end of the MAC PDU.

Except for the last subheader of the MAC PDU and MAC control elements of fixed size, there are six header fields in the MAC PDU subheader (R / R / E / LCID / F / L). The last subheader of the MAC PDU and the fixed size MAC control elements have only four header fields (R / R / E / LCID). Therefore, the MAC PDU subheader corresponding to the padding is composed of four header fields (R / R / E / LCID).

Obviously, it is better to have BSR than no BSR. Therefore, the figure (b) of FIG. 22 should be used instead of the figure (a) or (b) of FIG. As a method of avoiding the diagram (b) of FIG. 25, the padding BSR may be included anywhere in the MAC PDU. If this is allowed, then the triggering condition of the padding BSR ensures that the picture (b) of Figure 22 is sent when there is a 2-byte padding space.

A MAC PDU is a bit string whose length is byte aligned. These bit strings can be represented as charts or lists, where the most significant bit (MSB) is the leftmost bit of the first line of the chart, and the least significant bit (LSB) is the rightmost bit of the last line of the chart. More generally, the bit string is read sequentially from left to right for each line. The bit order of each parameter field in the MAC PDU is indicated by the first MSB in the leftmost bit and the last LSB in the rightmost bit.

MAC SDUs are bit strings that are byte aligned (multiple of 8 bits) with respect to length. SDUs are included in the MAC PDU sequentially from the first bit.

MAC PDU subheaders have the same order as the corresponding MAC SDUs, MAC control elements and padding.

The MAC control elements, except the padding BSR, are placed before any MAC SDU. The padding BSR may be placed before or after any MAC SDU.

On the upside, padding occurs at the end of a MAC PDU, except when one byte is required but cannot be padded at the end of the MAC PDU.

In the downward direction, padding occurs at the end of a MAC PDU, except when one or two bytes are required but padding cannot be achieved at the end of the MAC PDU.

On the upside, if one padding byte is required but cannot be padded at the end of the MAC PDU, one MAC PDU subheader corresponding to the padding is included before the first MAC PDU subheader corresponding to the MAC SDU, or there is no such subheader. In this case, it is included before the last MAC PDU corresponding to the MAC control element.

In the downward direction, if one or two padding bytes are needed but padding cannot be achieved at the end of the MAC PDU, one or two MAC PDU subheaders corresponding to the padding are included before the first MAC PDU subheader corresponding to the MAC SDU, or If there is no such subheader, it is included before the last MAC PDU corresponding to the MAC control element.

At most one MAC PDU may be transmitted for each TB and each UE. Depending on the classification of the physical layer, one or two TBs may be transmitted for each TTI and each UE.

Note # 7

The MAC PDU header consists of one or more MAC subheader (s), each subheader corresponding to a MAC SDU, MAC control element or padding. There should not be more than one MAC PDU subheader for padding in a MAC PDU.

MAC PDU subheaders have the same order as the corresponding MAC SDUs, MAC control elements and padding.

MAC control elements (except padding BSR) are placed before any MAC SDU. The padding BSR is at the end of the MAC PDU.

Padding is at the end of a MAC PDU except when one byte is required but padding is not sufficient at the end of the MAC PDU.

When one byte is required but padding is not sufficient at the end of the MAC PDU, the MAC PDU subheader corresponding to the padding is inserted before the first MAC PDU subheader corresponding to the MAC SDU or, if no such subheader is present, corresponds to the MAC control element. It is located before the last MAC PDU.

When two bytes remain after filling a MAC PDU with MAC SDUs or MAC control elements (except BSR), it includes a short BSR.

At most one MAC PDU is transmitted for one TB and one UE. In addition, according to the physical layer classification, one or two TBs are transmitted for one TB and one UE.

Note # 8

Except for the last subheader of the MAC PDU and MAC control elements of fixed size, there are six header fields in the MAC PDU subheader (R / R / E / LCID / F / L). The last subheader of the MAC PDU and the fixed size MAC control elements have only four header fields (R / R / E / LCID). Therefore, the MAC PDU subheader corresponding to the padding is composed of four header fields (R / R / E / LCID).

The number of padding bits is the TB size minus the size of MAC SDUs or MAC CEs and the MAC subheaders associated with them. In this calculation, the MAC subheader of the last MAC SDU is considered to be of the form “R / R / E / LCID / F / L”.

Padding places MAC control elements except BSR before any MAC SDU.

On the padded BSR:

If the number of padding bits is equal to or greater than the size of the long BSR and the long BSR can fit into the MAC PDU, report the long BSR;

Otherwise, if the number of padding bits is equal to or greater than the size of the short BSR, and if the short BSR can fit in the MAC PDU, report the short BSR of the LCG of the highest priority logical channel with buffered data.

Note # 9

There are two ways to consider:

Option 1

On the padded BSR:

If the number of padding bits is equal to or greater than the size of the short BSR and less than the length of the long BSR, report the short BSR of the LCG of the highest priority logical channel with buffered data.

Otherwise, if the number of padding bits is equal to or greater than the size of the long BSR, report the long BSR.

The number of padding bits is the TB size minus the size of MAC SDUs or MAC CEs and the MAC subheaders associated with them. In this calculation, the MAC subheader of the last MAC SDU is considered to be of the form “R / R / E / LCID / F / L”.

Option 2

On the padded BSR:

If the number of padding bits is equal to or greater than the size of the long BSR and can include the F and L fields in all MAC subheaders for MAC SDUs in the MAC PDU, report the long BSR;

Otherwise, if the number of padding bits is equal to or greater than the size of the short BSR, and can include F and L fields in all MAC subheaders for MAC SDUs in the MAC PDU, the highest priority with buffered data is given. Report the short BSR of the LCG of the logical channel.

An unclear problem that may occur and a solution thereof will be described below.

Figure (a) of Figure 26 shows that there is enough space to add a long BSR. However, a short BSR is already included. According to the current standard, only one BSR can be added to a MAC PDU when multiple BSRs are triggered. Thus, only one of Short and Regular BSR or Long and Padding BSR is allowed in FIG. Similar problems are shown in Figures (b) and (c) of Figure 26.

Therefore, it is not clear which one to use. That is, it is not clear whether the Regular or Periodic BSR has a higher priority than the Padding BSR. Consider using long BSRs as much as possible. Alternatively, a short regular BSR may be replaced by a long padding BSR. On the other hand, to simplify the implementation, it is proposed to include several BSRs in one MAC PDU. In this way, the uncertainty can be resolved.

Accordingly, in order to solve the case of the plurality of BSRs described above, the format of FIG. 26 may be replaced with the format of FIG. 27 by including several BSRs in one MAC PDU.

As another solution, the UE may add one long BSR. That is, when the UE configures the MAC PDU, the UE may put a long BSR by combining the remaining space and the space already allocated for regular and periodic BSR. FIG. 28 shows what the MAC PDU behavior looks like when using this solution in the problem case of FIG.

Note # 10

It is important that the scheduler can distinguish between padding and regular BSR. If you remove the position constraint, you must use a separate LCID for the padding BSR. Here, the padding BSR should be specified directly by using a padding subheader.

If the number of padding bits is equal to or greater than the size of the short BSR and its subheaders, and less than the size of the long BSR and its subheaders, report the short BSR of the LCG of the highest priority logical channel with buffered data. .

Otherwise, if the number of padding bits is equal to or greater than the size of the long BSR and its subheaders, report the long BSR.

The overall rule for handling padding may be simpler than introducing exceptions: regardless of whether a regular BSR is included or not, the UE always adds the same rule to include the padding BSR.

If the BSR is already included in the MAC PDU, no additional BSR may be needed. This is because the additional BSR can increase the MAC processing procedure. Since the BSR fields are filled after the PDU is formed, there may be conquered BSRs.

If short BSR is used, it may mean that there are no buffered data in the other three groups not reported. Thus, one may imply the buffer state for all groups of Short BSR (ie, Regular or Periodic). On the other hand, when using a long BSR, it is also possible to report the buffer status of all groups.

Note # 11

Consider which BSRs will be included when multiple BSRs are triggered.

Even if several events occur until the BSR can be transmitted, only one BSR can be included in the MAC PDU.

For example, if the periodic timer expiration triggers a short BSR and there is enough padding space left to contain the long BSR, then the type of BSR to be included must be determined. If a regular short BSR is triggered and can only accommodate short BSRs in the padding space, then two short BSRs can be combined to form a long BSR. Several solutions to this situation will be possible.

Option A: The padding BSR is not triggered when a regular or periodic BSR is triggered. In this way, BSRs of different sizes can be avoided.

Option B: In the MAC PDU, one of a maximum Regular BSR or a Periodic BSR may be included, and a maximum of one Padding BSR may be included.

Option: If a Regular or Periodic BSR is triggered and a Padding BSR is also triggered, the largest BSR that can enter the MAC PDU is included.

The option A may be the most practical since it is simple.

There may be several kinds of BSR. If multiple BSRs are triggered, only one BSR is included.

However, the question arises which BSR to include when multiple BSRs are triggered. The padding BSR is not triggered if a regular or periodic BSR has already been triggered. The MAC object may not be able to determine which BSR to include when multiple BSRs are triggered. Serving (serving) The buffer status reporting procedure (Buffer Status reporting procedure) is used to inform the amount of data in the UL buffer of the terminal by giving information to the eNB. If at least one of the following situations occurs, the Buffer Status Report (BSR) will be triggered:

UL data arrives in the UE transmit buffer, and that data corresponds to a logical channel of higher priority than data already present in the UE transmit buffer, in which case the BSR used is referred to below as a regular BSR. Called;

UL resources are allocated and the number of padding bits is greater than the size of the BSR MAC control element, where the BSR is referred to below as the padding BSR;

If a serving cell change occurs, the BSR at this time is referred to below as a regular BSR;

PERIODIC BSR TIMER When expired, the BSR at this time is referred to as a periodic BSR.

For Regular and Periodic BSR:

If there is data buffered in the TTI to which the BSR was sent for only one LCG: short BSR report;

Otherwise, if there is data buffered in the TTI to which the BSR was sent for one or more LCGs: Long BSR Report.

For padding BSR:

If a Regular or Periodic BSR has not been triggered;

If the number of padding bits is greater than or equal to the size of the Short BSR and less than the size of the Long BSR, report the Short BSR of the LCG of the highest priority logical channel with buffered data. do.

Otherwise, if the number of padding bits is equal to or greater than the size of the long BSR, report the long BSR.

If the buffer status reporting procedure determines that the BSR has been triggered since the last BSR transfer:

If the UE has been allocated UL resources for new transmissions for this TTI:

Instructing the multiplexing and assembly procedure to form a BSR control element (MAC);

-Restart the periodic BSR timer (PERIODIC BSR TIMER).

Otherwise, if a regular BSR was triggered from the last BSR transfer:

Trigger a Scheduling Request

Even if several events occur until the BSR can be transmitted, only one BSR can be included in the MAC PDU.

The UL grant can accommodate all pending data, but if it is insufficient to accommodate the BSR MAC control element, it will cancel the pending BSR.

As described above, various embodiments of the present invention relate to a method and apparatus for processing a buffer status report (BSR). When BSR triggering is performed, the size of the BSR and the size (s) of the required subheader (s) are also considered. This may include or insert subheader (s) in the MAC PDU (or transport block (TB) or other data unit).

The buffer status reporting procedure is used to inform the serving eNB of the amount of data that can be transmitted to the UL buffer of the UE. For the buffer status reporting procedure, the UE may consider all radio bearers that are not suspended and also consider suspended radio bearers.

The Buffer Status Report (BSR) will be triggered when at least one of the following situations occurs:

UL data can be transmitted in an RLC object or PDCP object for a logical channel belonging to one LCG, and the data corresponds to a logical channel having a higher dominance than that of logical channels corresponding to any LCG. And if there is no data available for transmission on any logical channel that is already available for transmission or for one LCG, then this BSR is called a regular BSR;

If the UL resource is allocated and the number of padding bits is equal to or greater than the size of the BSR MAC control element, then the BSR is called a padding BSR;

If a serving cell change occurs, the BSR at this time is referred to below as a regular BSR;

If the timer RETX_BSR_TIMER expires and there is data that can be transmitted by the UE, then the BSR at this time is called a regular BSR;

The timer PERIODIC_BSR_TIMER expires, at which time the BSR is called a Periodic BSR;

For Regular and Periodic BSR:

If there is transmittable data in the TTI to which the BSR was sent for one or more LCGs: Long BSR report;

-If not, a short BSR.

For padding BSR:

If the number of padding bits is greater than or equal to the size of the Short BSR and its subheaders, and less than the size of the Long BSR and its subheaders:

If at least one LCG has buffered data in the TTI sent to the BSR: report the truncated BSR of the LCG with the transmittable data and the highest priority logical channel; ;

Otherwise short BSR report.

Otherwise, if the number of padding bits is greater than or equal to the size of the long BSR and its subheaders, report the long BSR.

If the Buffer Status reporting procedure determines that at least one BSR has been triggered or at least one BSR has been triggered from the last transmission of the BSR:

If the UE has been allocated UL resources for this new transmission of TTI:

Instructing the multiplexing and assembly procedure to form a BSR control element (MAC);

Start or restart the timer PERIODIC_BSR_TIMER, except when the BSR is a Truncated BSR;

-Start (if not running) or restart (if running) the timer (RETX_BSR_TIMER).

Otherwise, if a regular BSR is triggered:

-Tries to schedule scheduling requests.

A MAC PDU may contain at most one MAC BSR control element, even when multiple events trigger a BSR by the time a BSR can be transmitted, even if multiple events trigger the BSR until the BSR is available for transmission. In this case, Regular BSR and Periodic BSR take precedence over Padding BSR.

When the UE receives the new data transmission permission from the UL-SCH, the UE restarts (if running) the timer RETX_BSR_TIMER.

The UL grant can accept all pending data, but if it is insufficient to accommodate the BSR MAC control element additionally, it will cancel all triggered BSRs.

The MAC PDU is further described below (except DL-SCH and UL-SCH, transparent MAC and Random Access Response).

As shown in Figure 4, a MAC PDU has a MAC header, zero or more MAC Service Data Units (MAC SDUs), zero or more MAC control elements, and optionally padding.

MAC header and MAC SDUs have a variable length.

There are one or more MAC PDU subheaders in the MAC PDU header, each subheader corresponding to a MAC SDU, MAC control request or padding.

The MAC PDU subheader may consist of six header fields (R / R / E / LCID / F / L), except for the last subheader of the MAC PDU and MAC control elements of fixed size. The last subheader of the MAC PDU and the subheaders of the fixed size MAC control elements consist of only four header fields (R / R / E / LCID). Therefore, the MAC PDU subheader corresponding to the padding is composed of four header fields (R / R / E / LCID).

MAC PDU subheaders have the same order as the corresponding MAC SDUs, MAC control elements and padding.

MAC control elements are placed before any MAC SDU.

Padding is at the end of a MAC PDU except when one or two byte padding is required but padding is not sufficient at the end of the MAC PDU. The padding can have any value and the UE ignores it.

If one or two byte padding is required but padding is not sufficient at the end of the MAC PDU, one or two MAC PDU subheaders corresponding to the padding are inserted before the first MAC PDU subheader corresponding to the MAC SDU, or such subheaders If not, it is located before the last MAC PDU subheader corresponding to the MAC control element.

 At most one MAC PDU may be transmitted for one UE and one TB.

According to the present invention, for MAC Control Elements, there are Buffer Status Report MAC Control Elements.

The BSR MAC control element consists of:

Short BSR and Trunked BSR formats: one LCG ID field and one corresponding Buffer Size field (Figure 7); or

Long BSR Format: 4 Buffer Size fields corresponding to LCG IDs # 0 to # 3 (FIG. 8).

BSR formats are identified by LCIDs of MAC PDU subheaders.

The LCG ID field and the Buffer Size field are defined as follows:

LCG ID: The Logical Channel Group ID field indicates a group of logical channel (s) for which a buffer status is reported. This field is 2 bits long.

Buffer Size: The Buffer Size field indicates the total amount of data available from all logical channels of one logical channel group after the MAC PDU is formed. This data amount is expressed in number of bytes. It includes all data that can be transmitted in the RLC layer and the PDCP layer. The buffer size calculation does not take into account the sizes of the RLC and MAC headers. This field is 6 bits long.

The present invention provides a method for determining whether there is padding space in a configured MAC PDU, and comparing the number of padding bits to a combined size of a buffer status report (BSR) and a related sub-header. And when the number of the padding bits is greater than the combined size of the buffer status report (BSR) and a subheader associated with the buffer status report (BSR), triggering a buffer status report (BSR). Buffer Status Report) is provided.

In addition, adding the BSR and its subheaders to the MAC PDU; And setting a logical channel identification (LCID) in the subheader to indicate that the BSR has been triggered by padding and the BSR has been added.

The method includes receiving permission to configure a MAC PDU from the network; And configuring the MAC PDU using higher logical channel data and MAC control elements. The MAC PDU may add a short BSR having a logical channel identification (LCID) field of 2 bytes and a buffer size of 6 bytes. Separate Logical Channel Identification (LCID) fields may be set for Short BSR and Trunked BSR. The LCID field may identify a logical channel demonstration or MAC control element or padding of a corresponding MAC SDU for each of the DL-SCH and the UL-SCH. The LCID field may include a first value for short BSR or 12 values for long BSR. The size of the BSR is 4 bytes or 8 bytes.

Referring to Figure 29, the present invention provides a mobile communication system, a confirmation unit for checking whether there is a padding space in the configured MAC PDU; A comparison unit for comparing the number of padding bits with a combined size of a buffer status report (BSR) and a subheader related thereto; And a processing unit for triggering a buffer status report (BSR) and cooperating with the verification unit and the comparison unit if the number of the padding bits is greater than the combined size of the buffer status report (BSR) and a subheader associated therewith. A media access control (MAC) entity is provided.

In addition, the processor adds the BSR and its subheaders to the MAC PDU and sets a logical channel identification (LCID) in the subheader to indicate that the BSR has been triggered by padding and the BSR has been added.

The media access control (MAC) entity receives permission from the network to construct a MAC PDU; And configuring the MAC PDU using higher logical channel data and MAC control elements. The MAC PDU may add a short BSR having a logical channel identification (LCID) field of 2 bytes and a buffer size of 6 bytes. Separate Logical Channel Identification (LCID) fields may be set for Short BSR and Trunked BSR. The LCID field may identify a logical channel demonstration or MAC control element or padding of a corresponding MAC SDU for each of the DL-SCH and the UL-SCH. The LCID field may include a first value for short BSR or 12 values for long BSR. The size of the BSR is 4 bytes or 8 bytes.

The various features and concepts described herein may be implemented in software, hardware or a combination thereof. For example, a computer program (executed by a computer, terminal, or network device) for a method and apparatus for processing buffer status reports / information (BSR) consists of one or more program code portions that perform various functions. Can be. In addition, a software tool (executed by a computer, terminal, or network device) for a method and apparatus for processing buffer status reports / information (BSR) is comprised of one or more program code portions that perform various functions. Can be configured.

The method and apparatus for processing the buffer status report / information (BSR) of the present invention is compatible with various techniques and standards.

Some of the features described herein relate to several types of standards, such as GSM, 3GPP, LTE, IEEE, 4G, and the like. These exemplary standards are not limiting and other relevant standards and techniques are also applicable to the various features and concepts described herein.

1 illustrates an example of a network structure of an Evolved Universal Mobile Telecommunications System (E-UMTS).

2 illustrates a control plane radio access interface protocol between a terminal and a base station according to the 3GPP radio access network standard.

3 illustrates a user plane radio access interface protocol between a terminal and a base station according to the 3GPP radio access network standard.

4 illustrates an example MAC PDU format used by a MAC object.

5 illustrates an example MAC PDU subheader format used by a MAC object.

6 illustrates an example MAC PDU subheader format used by a MAC object.

7 exemplarily shows a MAC control element (CE) of short BSR and truncated BSR.

8 exemplarily shows a MAC control element (CE) of a long BSR.

9 illustrates example MAC PDUs with and without BSR with data and padding.

FIG. 10 illustrates an example in which the UE is instructed to form a MAC PDU having a size of L + M + 3 bytes.

Figure 11 shows an example of a MAC PDU with two bytes of space remaining and one byte used as padding BSR and one byte MAC subheader that may be used in addition.

FIG. 12 shows two implementations forming a MAC PDU with BSR with and without a subheader.

13 shows three implementations forming a MAC PDU including a BSR.

14 shows two additional implementations that form a MAC PDU including a BSR.

15 shows three additional implementations that form a MAC PDU including a BSR.

16 shows whether the padding LCID does not distinguish whether there is still data in the buffer of the UE and does not waste 2 bytes of padding LCID to help the eNB scheduler efficiency, and the 2 bytes are used for the short BSR.

Figure 17 shows two implementation schemes (a) and (b) that indicate whether or not a padding BSR is present.

Figure 18 shows two possible examples of the location of the padding BSR when using direct indication.

FIG. 19 illustrates an example in which a short BSR is already included in a MAC PDU, so that two bytes remain to use a long BSR instead of a short BSR.

20 shows an example in which 2 bytes remain after the long BSR is included.

Figure 21 shows an example in which two bytes remain after a long BSR is included in case of a direct padding BSR indication.

Fig. 22 illustrates an example in which (bytes) format (b) should be used instead of format (a) because two bytes are sufficient for short BSR addition.

Figure 23 shows an example in which 2 bytes remain in a MAC PDU already containing a short BSR.

24 shows an example in which 2 bytes remain in a MAC PDU already including a long BSR.

25 shows an example of using 2 bytes of remaining space of the transport block in which the padding BSR is located last.

FIG. 26 illustrates another situation in which the remaining space is sufficient for adding a long BSR and a plurality of BSRs may be included in the MAC PDU.

27 shows that a plurality of BSRs are included in one MAC PDU.

FIG. 28 shows an example of combining the remaining empathy and the allocation space for the Regular and Periodic BSR to be included in the long BSR.

FIG. 29 shows an example architecture of a UE and an eNB with specific protocol layers including a MAC object.

Claims (28)

In the mobile communication system, Confirming, by the mobile terminal, whether there is padding space in the configured MAC PDU; Comparing, by the mobile terminal, the number of padding bits with a combined size of a buffer status report (BSR) and a sub-header associated therewith; And If the number of the padding bits is greater than or equal to the combined size of the buffer status report (BSR) and the sub-header associated with it, the buffer status report (BSR) is triggered. Buffer Status Report). The method of claim 1, Receiving, by the mobile terminal, permission from the network to configure the MAC PDU; And The mobile terminal further comprises the step of configuring the MAC PDU by using the upper logical channel data and MAC control elements (BSR) processing method of the Buffer Status Report (BSR). . The method of claim 2, The MAC PDU includes a padding buffer status report comprising a short BSR having a Logical Channel Group (LCG) identification field of 2 bits and a buffer size of 6 bits. How to process BSR: Buffer Status Report. The method of claim 1, And a logical channel identification (LCID) field is included in the subheader to indicate that the BSR has been added. The method of claim 1, The LCID field is a method of processing a padding buffer status report (BSR) characterized by identifying a logical channel demonstration of a corresponding MAC SDU or a corresponding MAC control element or type of padding of each of DL-SCH and UL-SCH. . The method of claim 4, wherein And wherein the LCID field includes a first value for a short BSR or a second value for a long BSR. The method of claim 1, The size of the BSR is 1 byte or 3 bytes, characterized in that for processing a padding buffer status report (BSR: Buffer Status Report). In the mobile communication system, A check unit for checking whether there is a padding space in the configured MAC PDU; A comparison unit for comparing the number of padding bits with a combined size of a buffer status report (BSR) and a subheader related thereto; And If the number of the padding bits is greater than or equal to the combined size of the buffer status report (BSR) and the sub-header associated with it, a processor that triggers a buffer status report (BSR) and cooperates with the verification unit and the comparison unit. And a medium access control (MAC) entity of the mobile terminal. The method of claim 8, Receiving permission for configuring the MAC PDU from a network; And And further configuring the MAC PDU using higher logical channel data and MAC control elements. 18. The medium access control (MAC) entity of the mobile terminal. The method of claim 9, The MAC PDU includes a short BSR having a 2-bit Logical Channel Group (LCG) identification field and a 6-bit buffer size. Control entity. The method of claim 8, Media access control (MAC) entity of a mobile terminal, characterized in that the subheader includes a logical channel identification (LCID) field to inform that the BSR has been added. The method of claim 8, The LCID field identifies a logical channel demonstration of a corresponding MAC SDU or a type of corresponding MAC control element or padding of each of DL-SCH and UL-SCH. The method of claim 11, The LCID field includes a first value for short BSR or a second value for long BSR. The method of claim 8, Media access control (MAC) entity of a mobile terminal, characterized in that the size of the BSR is 1 byte or 3 bytes. In the mobile communication system, Confirming, by the mobile terminal, whether there is padding space in the configured MAC PDU; Comparing, by the mobile terminal, the number of padding bits with a combined size of a buffer status report (BSR) and a sub-header associated therewith; Triggering a buffer status report (BSR) if the number of padding bits is greater than or equal to the combined size of the buffer status report (BSR) and its associated subheader; Adding the BSR and its subheaders to the MAC PDU; And Setting a logical channel identification (LCID) field in the subheader to indicate that the BSR has been added; and adding a padding buffer status report (BSR) to configure a data unit. . In the mobile communication system, A check unit for checking whether there is a padding space in the configured MAC PDU; A comparison unit for comparing the number of padding bits with a combined size of a buffer status report (BSR) and a subheader related thereto; And If the number of the padding bits is greater than or equal to the combined size of the buffer status report (BSR) and its associated subheaders, trigger a buffer status report (BSR), and determine the BSR and its subheaders in the MAC PDU. And a processing unit cooperating with the checking unit and the comparing unit for setting a logical channel identification (LCID) field in the subheader to indicate that the BSR has been added. MAC) entity. The method of claim 15, The LCID field includes a first value for a short BSR, a second value for a long BSR, or a third value for a truncated BSR. Buffer Status Report) to configure the data unit. The method of claim 16, The LCID field may include a first value for short BSR or a second value for long BSR or a third value for Trunked BSR. MAC) entity. In the mobile communication system, Confirming, by the mobile terminal, whether there is padding space in the configured MAC PDU; Comparing, by the mobile terminal, the number of padding bits with a combined size of a buffer status report (BSR) and a sub-header associated therewith; And If the number of padding bits is greater than or equal to the combined size of the buffer status report (BSR) and its associated sub-header, in the step of triggering a buffer status report (BSR), the number of padding bits, short (Short) Short BSR based on a comparison between the size of the BSR plus its associated subheader, the long BSR plus its associated subheader, and the presence of a Logical Channel Group (LCG). And a Buffer Status Report (BSR), wherein at least one of a Trunked BSR and a Long BSR is optionally reported.  20. The padding buffer status report of claim 19, wherein the long BSR is reported if the number of padding bits is greater than or equal to the length of the long BSR plus its associated subheader. : How to configure the data unit by adding Buffer Status Report.  20. The method of claim 19, wherein if the number of padding bits is greater than or equal to the size of the short BSR plus its associated subheader, but less than the size of the long BSR plus the associated subheader. And if the LCG has data for transmission, adding a Padded Buffer Status Report (BSR), characterized in that the truncated BSR is reported.  22. The data unit of claim 21, wherein a truncated BSR of the LCG is reported with a highest priority logical channel of data for the transmission. How to configure.  20. The method of claim 19, wherein if the number of padding bits is greater than or equal to the size of the short BSR plus its associated subheader, but less than the length of the long BSR plus the associated subheader plus one LCG. If there is data for transmission, the short (BSR) is reported, characterized in that for adding a padding buffer status report (BSR: Buffer Status Report). In the mobile communication system, A check unit for checking whether there is a padding space in the configured MAC PDU; A comparison unit for comparing the number of padding bits with a combined size of a buffer status report (BSR) and a subheader related thereto; And If the number of padding bits is greater than or equal to the combined size of the buffer status report (BSR) and its associated subheader, the number of padding bits, short (Short) in triggering a buffer status report (BSR). Short BSR, shortened, based on a comparison between the size of the BSR plus its associated subheader, the length of the Long BSR plus its associated subheader, and the presence of a Logical Channel Group (LCG). And a processing unit cooperating with the verification unit and the comparison unit, wherein at least one of a (Truncated) BSR and a Long BSR is optionally reported.  25. The medium access control of claim 24, wherein the long BSR is reported if the number of padding bits is greater than or equal to the length of the long BSR plus its associated subheader. (MAC) entity.  25. The method of claim 24, wherein if the number of padding bits is greater than or equal to the size of the short BSR plus its associated subheader, but less than the size of the long BSR plus the associated subheader. And if the LCG has data for transmission, the truncated BSR is reported.  27. The medium access control (MAC) entity of claim 26, wherein the Trunked BSR of the LCG is reported with the highest priority logical channel of data for the transmission.  25. The method of claim 24, wherein if the number of padding bits is greater than or equal to the size of the short BSR plus its associated subheader, but less than the length of the long BSR plus the associated subheader plus one LCG. If there is data for transmission, the short BSR is reported, the medium access control (MAC) entity of the mobile terminal.

Images