Patent Description:
The following abbreviations are herewith defined, some of which are referred to within the following description: Third Generation Partnership Project (3GPP), Downlink (DL), Evolved Node B (eNB), European Telecommunications Standards Institute (ETSI), Frequency Division Duplex (FDD), Frequency Division Multiple Access (FDMA), Long Term Evolution (LTE), Next Generation Node B (gNB), New Radio (NR), Negative Acknowledgement (NACK), Orthogonal Frequency Division Multiplexing (OFDM), Single Carrier Frequency Division Multiple Access (SC-FDMA), System Information (SI), Signal to Interference plus Noise Ratio (SINR), Transport Block (TB), Time-Division Duplex (TDD), Time Division Multiplex (TDM), User Entity/Equipment (Mobile Terminal) (UE), Uplink (UL), Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), Transmission Configuration Indication (TCI), Physical Downlink Control Channel (PDCCH), Block Error Rate (BLER), Media Access Control (MAC), physical (PHY), Random Access Channel (RACH), Physical Random Access Channel (PRACH), , Single Side Band (SSB), Radio Resource Control (RRC), Control Resource Set (CORSET or CORESET), Cell Radio Network Temporary Identifier (C-RNTI), Cyclic Redundancy Check (CRC), Quasi co-location (QCL), Physical Downlink Shared Channel (PDSCH), Control Element (CE), Transmit (TX), Receive (RX), Vehicle to Everything (V2X), buffer status report (BSR), Proximity-based service (ProSe), ProSe Per-Packet Priority (PPPP), Carrier Aggregation (CA), logical channel (LC), logical channel group (LCG).

For carrier aggregation, packet duplication on sidelink is enabled to enhance the reliability of sidelink packet transmission. As for the packet duplication, sidelink packet duplication on a single carrier is not supported. This means that the packets and duplicated packets need to be transmitted in different carriers. When V2X (Vehicle to Everything) UE is configured in scheduling mode, i.e. mode <NUM>, packet duplication function on sidelink is controlled by eNB, Thus the eNB needs to know the buffer status of the duplicated packets of logical channels that have activated duplication in a logical channel group, so that the eNB can schedule packets and duplicated packets on different carriers and allocate suitable resources. However, existing BSR (buffer status report) mechanism for resource requesting is based on service priority, i.e. PPPP (ProSe Per-Packet Priority), and therefore cannot reflect buffer statuses of packets and duplicated packets separately.

<NPL>; this document discusses the detailed BSR procedure and format considering new characteristics in NR, including BSR parameter configuration; BSR triggers; and BSR format.

<NPL>; this document discusses more detail focusing on control and restriction of the packet duplication, according to the preamble of the independent claims.

Understanding that these drawings depict only some embodiments, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:.

Accordingly, embodiments may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may generally all be referred to herein as a "circuit", "module" or "system". Furthermore, embodiments may take the form of a program product embodied in one or more computer readable storage devices storing machine-readable code, computer readable code, and/or program code, referred to hereafter as "code".

Certain functional units described in this specification may be labeled as "modules", in order to more particularly emphasize their independent implementation.

This operational data may be collected as a single data set, or may be distributed over different locations including over different computer readable storage devices, Where a module or portions of a module are implemented in software, the software portions are stored on one or more computer readable storage devices.

The storage device may be, for example, but need not necessarily be, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

A non-exhaustive list of more specific examples of the storage device would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, random access memory ("RAM"), read-only memory ("ROM"), erasable programmable read-only memory ("EPROM" or "Flash Memory"), portable compact disc read-only memory ("CD-ROM"), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Code for carrying out operations for embodiments may be any number of lines and may be written in any combination of one or more programming languages including an object-oriented programming language such as Python, Ruby, Java, Smalltalk, C++, or the like, and conventional procedural programming languages, such as the "C" programming language, or the like, and/or machine languages such as assembly languages. The code may be executed entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the very last scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network ("LAN") or a wide area network ("WAN"), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid any obscuring of aspects of an embodiment.

This code may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which are executed via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the schematic flowchart diagrams and/or schematic block diagrams for the block or blocks.

The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices, to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function/act specified in the schematic flowchart diagrams and/or schematic block diagrams block or blocks.

The code may also be loaded onto a computer, other programmable data processing apparatus, or other devices, to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the code executed on the computer or other programmable apparatus provides processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

Although various arrow types and line types may be employed in the flowchart and/or block diagrams, they are understood not to limit the corresponding embodiments.

<FIG> depicts an embodiment of a wireless communication system <NUM> for reporting buffer status. In one embodiment, the wireless communication system <NUM> includes remote units <NUM> and base units <NUM>. Even though a specific number of remote units <NUM> and base units <NUM> are depicted in <FIG>, one skilled in the art will recognize that any number of remote units <NUM> and base units <NUM> may be included in the wireless communication system <NUM>.

The remote units <NUM> may be referred to as subscriber units, mobiles, mobile stations, users, terminals, mobile terminals, fixed terminals, subscriber stations, UE, user terminals, a device, or by other terminology used in the art.

A remote unit may connect to the base unit with one or more cells.

The base units <NUM> may be distributed over a geographic region. In certain embodiments, a base unit <NUM> may also be referred to as an access point, an access terminal, a base, a base station, a Nodc-B, an eNB, a gNB, a Home Node-B, a relay node, a device, or by any other terminology used in the art. The base units <NUM> are generally part of a radio access network that includes one or more controllers communicably coupled to one or more corresponding base units <NUM>.

In one implementation, the wireless communication system <NUM> is compliant with NR (<NUM>). More generally, however, the wireless communication system <NUM> may implement some other open or proprietary communication protocol.

The base units <NUM> may serve a number of remote units <NUM> within a serving area, for example, a cell (or a cell sector) or more cells via a wireless communication link.

<FIG> depicts one embodiment of an apparatus <NUM> that may be used for reporting buffer status. The apparatus <NUM> includes one embodiment of the remote unit <NUM>. Furthermore, the remote unit <NUM> may include a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM>, and a receiver <NUM>. In some embodiments, the input device <NUM> and the display <NUM> are combined into a single device, such as a touch screen. In certain embodiments, the remote unit <NUM> may not include any input device <NUM> and/or display <NUM>. In various embodiments, the remote unit <NUM> may include at least one of the processor <NUM>, the memory <NUM>, the transmitter <NUM> and the receiver <NUM>, and may not include the input device <NUM> and/or the display <NUM>.

In some embodiments, the memory <NUM> stores data relating to system parameters.

In some embodiments, the input device <NUM> may be integrated with the display <NUM>, for example, as a touch screen or similar touch-sensitive display. In some embodiments, the input device <NUM> includes a touch screen such that text may be input using a virtual keyboard displayed on the touch screen and/or by handwriting on the touch screen.

As another, non-limiting example, the display <NUM> may include a wearable display such as a smart watch, smart glasses, a heads-up display, or the like.

For example, the input device <NUM> and display <NUM> may form a touch screen or similar touch-sensitive display.

The transmitter <NUM> is used to provide UL communication signals to the base unit <NUM> and the receiver <NUM> is used to receive DL communication signals from the base unit <NUM>. In various embodiments, the transmitter <NUM> and the receiver <NUM> may transmit and receive resources via different cells. In one embodiment, the transmitter <NUM> and the receiver <NUM> may be part of a transceiver,.

<FIG> depicts one embodiment of an apparatus <NUM> that may be used for reporting buffer status. The apparatus <NUM> includes one embodiment of the base unit <NUM>. Furthermore, the base unit <NUM> may include at least one of a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM> and a receiver <NUM>. As may be appreciated, the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> may be substantially similar to the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> of the remote unit <NUM>, respectively.

Although only one transmitter <NUM> and one receiver <NUM> are illustrated, the base unit <NUM> may have any suitable number of transmitters <NUM> and receivers <NUM>.

Different services are transmitted via different logical channels. Different services have different priorities. Therefore, the logical channels for transmitting different services may be grouped as different logical channel groups depending on different priorities of the services transmitted thereon. For example, there may be four logical channel groups (LCGs): LCG1, LCG2, LCG3 and LCG4 with decreasing priorities. All of the logical channels (LCs) in one LCG (any one of LCG1, LCG2, LCG3 and LCG4) have the same priority.

In mode <NUM>, the eNB is responsible for controlling communications of the UEs. In order to make appropriate scheduling, the eNB needs to know the size of the data to be transmitted via LCGs. This is accompanied by reporting buffer status from the UE to the eNB. The buffer status is sent from the UE to the eNB in a BSR MAC CE ("Buffer Status Report" "Media Access Control" "Control Element"). When packets to be transmitted on a LCG arrive at a buffer for the LCG, the buffer status is sent in the BSR MAC CE from the UE to the eNB.

Each buffer status indicates the buffer size of each LCG. The BSR MAC CE structure includes "destination index", "LCG ID" and "buffer size" for each LCG. For example, in the condition of four LCGs (LCG1, LCG2, LCG3 and LCG4), the BSR MAC CE structure includes four buffer statuses.

<FIG> is a schematic figure illustrating a BSR MAC CE containing buffer status of both the first packets and the duplicated packets according to the first embodiment. The first packets contain the data to be transmitted on a LCG. The duplicated packets contain the data to be transmitted on the LCG (or the corresponding LCG) in duplication in another carrier.

In <FIG>, each "Legacy BSR Info" represents the buffer status for each LCG. As shown in <FIG>, four "Legacy BSR Info" for LCG1, LCG2, LCG3 and LCG4 are contained in the MAC CE for reporting buffer status.

In addition, the MAC CE for reporting buffer status also contains four "duplicated packet buffer status" for LCG1, LCG2, LCG3 and LCG4 (or corresponding LCG1, corresponding LCG2, corresponding LCG3 and corresponding LCG4).

Each "duplicated packet buffer status" is added after each "Legacy BSR Info". The "duplicated packet buffer status" is used to report the buffer size for the corresponding logical channel group on which the duplicated packets transmit.

For carrier aggregation, packet duplication on sidelink is enabled to enhance the reliability of sidelink packet transmission. Packet duplication means that the same packet is transmitted via different carriers, so that the reliability of receiving the packet is enhanced. Therefore, whether a packet is transmitted in duplication depends on the requirement of the reliability of the packets (or of the service).

Different services that are transmitted in different logical channels have different requirements of reliability. In other words, different LCs have different requirements of reliability.

Therefore, different LCs in the same LCG may have different requirements of reliability. Suppose three LCs (LCI, LC2 and LC3), that have the same priority, are contained in one LCG; and LC1, LC2 and LC3 have different requirements of reliability. Suppose LC1, which has the highest requirement of reliability, is necessary to be transmitted in duplication; while LC2 and LC3, depending on their requirements of reliability, are not necessary to be transmitted in duplication. Therefore, for the LCG that contains LC1, LC2 and LC3, only LC1 is necessary to be transmitted in duplication, while LC2 and LC3 are not necessary to be transmitted in duplication. Therefore, in the condition that the duplicated packets arrive at a buffer for LC1, the buffer status information for the corresponding logical channel group is included.

As described above, in mode <NUM>, the eNB is responsible for controlling communications of the UEs. In order to make appropriate scheduling, the eNB is necessary to know the buffer status (buffer size). Traditionally, only the buffer size for a whole LCG is reported to the eNB. However, the buffer size of the corresponding LCG that is necessary to be transmitted in duplication (in the previous example, the buffer size of LC1) may be different from the buffer size of the whole LCG (the buffer size of all of the LC1, LC2 and LC3). Therefore, according to an embodiment, the "duplicated packet buffer status" is used to report the buffer size of all of the logical channels that have activated packet duplication in the logical channel group.

As discussed in earlier example, for the "Legacy BSR Info for LCGI", the LCG1 is practically composed of LC1, LC2 and LC3, while the legacy buffer status for the LCG1 indicates a total amount of data available for transmission of all of LC1, LC2 and LC3. On the other hand, for the "Duplicated packet buffer status for LCGI", although the LCG1 is also practically composed of LC1, LC2 and LC3, the duplicated buffer status for LCG1 indicates a total amount of duplicated data available for transmission of all of logical channels that have activated duplication (i.e. of only LC1) in the logical channel group. Therefore, the LCG1 in "Legacy BSR Info for LCG1" and the LCG1 in "Duplicated packet buffer status for LCG1" are not exactly the same. To make differentiation, as appropriate, the LCG1 in "Legacy BSR Info for LCG1" and the LCG1 in "Duplicated packet buffer status for LCG1" are corresponding, for example, the LCG1 in "Legacy BSR Info for LCG1" may be referred to as LCG1 (or LCG) while the LCG1 in "Duplicated packet buffer status for LCG1" may be referred to as corresponding LCG1 (or corresponding LCG), or vice verse.

As shown in <FIG>, the "duplicated packet buffer status for LCG1" is positioned after the "Legacy BSR Info for LCG1"; the "duplicated packet buffer status for LCG2" is positioned after the "Legacy BSR Info for LCG2"; the "duplicated packet buffer status for LCG3" is positioned after the "Legacy BSR Info for LCG3"; and the "duplicated packet buffer status for LCG4"' is positioned after the "Legacy BSR Info for LCG4".

<FIG> shows all of "duplicated packet buffer status for LCG1", "duplicated packet buffer status for LCG2", "duplicated packet buffer status for LCG3" and "duplicated packet buffer status for LCG4". On the other hand, duplicated packet buffer status for a particular LCG is only present when there has available duplicated packets for transmission of activated duplicated logical channel(s) in the particular LCG. That is to say, in the condition that none of the LCs in the particular LCG is necessary to be transmitted in duplication, it is unnecessary to include the duplicated packet buffer status for said particular LCG.

<FIG> shows the detailed BSR MAC CE format containing buffer status for both LCGs and corresponding LCGs according to the first embodiment. In <FIG>, each row represents one byte (i.e. eight bits). In <FIG>, "Oct" means "Octet", i.e. a byte that is composed of eight bits. Both "Legacy BSR Info" and "duplicated packet buffer status" includes information of twelve bits. In particular, the "Legacy BSR Info" fields include destination index (<NUM> bits), LCG ID (<NUM> bits), and buffer size (<NUM> bits); while the "duplicated packet buffer status" also includes destination index (<NUM> bits), LCG ID (<NUM> bits), and buffer size (<NUM> bits).

The destination index for duplicated packet buffer status is the same as destination index of the corresponding legacy LCG (i.e. destination index1d is the same as destination index<NUM>). Traditionally, LCG is defined per ProSe (Proximiry-based Services) Destination. That is, one LCG is associated with one ProSe Destination. In the embodiment, since the destination index1d is the same as destination index<NUM>, two LCGs (i.e. a LCG and a corresponding LCG) are associated with the same ProSe Destination.

The LCG ID of duplicated packet buffer status is also the same as LCG ID of the corresponding legacy LCG (i.e. LCG ID1d is the same as LCG ID<NUM>). The same destination index and LCG ID is used to indicate the following buffer size is for duplicated packet buffer size of logical channels that have activated duplication.

From the point of the view of the eNB, when receiving a particular destination index and LCG ID for the first time, the eNB knows that the following buffer size is for the "Legacy BSR Info", and when receiving the same particular destination index and LCG ID for the second time, the eNB knows that the following buffer size is for the "duplicated packet buffer status".

The buffer size of duplicated packet buffer status is the total amount of data available across all logical channels that activated duplication in a LCG to a ProSe destination.

As a whole, the destination index1d is the same as the destination index<NUM>; the LCG ID1d is the same as the LCG ID<NUM>; and the Buffer Size<NUM> is the total amount of data across all logical channels in a LCG while the Buffer Size1d is the total amount of data available across all logical channels that have activated duplication in the LCG (or a corresponding LCG).

The number of bits (or bytes) that can be used to transmit the BSR information is determined by UL grant. If the number of bits in the UL grant is not enough for the size of a MAC CE for reporting buffer status, it is preferable to report a truncated BSR containing as much buffer status as possible, unless buffer status for both the LCG and the corresponding LCG cannot be contained together. This is the truncated BSR rule, which means that if the duplicated packet buffer status of a specific LCG cannot be contained because of limited UL grant size, the legacy buffer status of the corresponding LCG is not included either. This is for the purpose of avoiding misunderstanding in eNB that there is no duplicated packet for the specific LCG.

<FIG> shows an example of the truncated BSR rule. In <FIG>, if the full BSR information contains <NUM> bytes, but UL grant is only <NUM> bytes, then based on the truncated BSR rule, both LCG3 (i.e. Destination index<NUM>, LCG ID<NUM>, buffer size<NUM>) and LCG3d (i.e. Destination index3d, LCG ID3d, buffer size3d) are not included in BSR MAC CE, although there is enough space for LCG3. If the LCG3 is included while LCG3d is not included, the eNB would misunderstand that all of packets transmitted on LCG3 do not need to be transmitted in duplication.

<FIG> also shows reserved bits. As both "Legacy BSR Info" and "duplicated packet buffer status" includes information of twelve bits, in consideration that the MAC CE shall be transmitted in full bytes, if the total number of buffer status information for legacy LCG and new LCG is odd, four reserved bits shall be added at the last of MAC CE.

In the first embodiment, the LCG is composed of LCs according to priorities, which means that all of LCs in a particular LCG have the same priority configuration. The same priority configuration may mean the same priority. In the condition that the priorities of LCs are configured by the eNB, the same priority configuration may mean that there are multiple priorities for different LCs contained in a particular LCG. In this sense, the priority of a particular LCG means the highest priority of LC(s) contained in the particular LCG. The duplicated packet buffer status is related to a corresponding LCG that is composed of LC(s) that are necessary to be transmitted in duplication of the particular LCG. Therefore, the LC(s) that are necessary to be transmitted in duplication in the particular LCG also have the same priority configuration. In particular, all of the LCs are contained in LCG1, LCG2, LCG3 and LCG4 according to their priority configurations. That is, the LCs contained in the same LCG have the same priority configuration, and the LCs contained in different LCGs have different priority configurations. For example, the LCs (LC1, LC2, LC3 and LC4) contained in LCG1 have the highest priority LC, the LCs (e.g. LC5, LC6, LC7,. ) contained in LCG2 have the second highest priority LC, the LCs contained in LCG3 have the third highest priority LC, and the LCs contained in LCG4 have the lowest priority LC. Because the composition of the LCG does not consider the requirement of reliabilities in the first embodiment, the LC(s) of a particular LCG that are necessary to be transmitted in duplication may have different requirement of reliabilities.

In the following second and third embodiments, new LCGs will be composed according to different parameter or rule, such as reliabilities. For example, the LCs contained in LCG1, LCG2, LCG3 and LCG4 that are necessary to be transmitted in duplication may be recomposed into new LCG1, new LCG2, new LCG3 and new LCG4 according to the requirement of reliabilities. As another example, the LCs that are necessary to be transmitted in duplication may be recomposed into new LCGs according to eNB configuration. That is to say, the eNB will configure which LCs that are necessary to be transmitted in duplication belong to which new LCG.

<FIG> is a schematic diagram illustrating a BSR MAC CE containing buffer status according to the second embodiment. In the second embodiment, duplicated packet buffer status of new LCGs is added after legacy BSR info of all LCGs. In this case, duplicated packet buffer status of one or multiple new LCGs can be reported, and the new LCG means that the logical channels can be grouped by different parameter or rule compared with LCG in legacy BSR.

<FIG> is a schematic diagram illustrating a BSR MAC CE containing buffer status according to the third embodiment. In the third embodiment, new BS information and legacy BS information are prioritized according to the priority of the LCGs. The priority of new LCG is determined by the priority of the LCs contained in the new LCG.

Similar to the first embodiment, in the second and third embodiments, both buffer status for the LCG and the corresponding LCG include destination index, LCG ID, buffer size fields, as shown in <FIG> and <FIG>.

The destination index of the buffer status for the LCG (such as Destination index, as shown in <FIG>) is the same as the destination index of the buffer status for the corresponding new LCG (such as Destination index d l, as shown in <FIG>).

The LCG ID of buffer status for the corresponding new LCG is the ID of new LCG, and can be configured by eNB.

The buffer size of the buffer status for the LCG (such as Buffer Size<NUM> as shown in <FIG>) indicates a total amount of data available for transmission across all of logical channels in the LCG. Similarly, the buffer size of the buffer status for the new LCG (which can be also referred to as the corresponding LCG, or the corresponding new LCG) (such as Buffer Sized <NUM> as shown in <FIG>) indicates a total amount of duplicated data available for transmission across all of logical channels that have activated duplication in the new logical channel group.

In the second and third embodiment, the eNB, when receiving a particular destination index for the first time, knows that the following buffer size is for the "Legacy BSR Info", and when receiving the particular destination index for the second time, knows that the following buffer size is for the "duplicated packet buffer status". Thus, all of the LCs in a new LCG should have the same destination. This means that all of LCs in the new LCG should come from the same legacy LCG and also have the same requirement of reliability configuration.

The same reliability configuration may mean the same reliability. For example, suppose that the legacy LCG is composed of LC1, LC2, LC3 and LC4, in which LC1 and LC2 have the highest requirement of reliability, LC3 has the second highest requirement of reliability, and LC4 has the lowest requirement of reliability. In addition, suppose that, according to the requirement of reliabilities, the packets transmitted on LC1, LC2 and LC3 should be transmitted in duplication. Therefore, LC1 and LC2, that have the same requirement of reliability, will compose new LCG1, while LC3 will compose new LCG2.

Similar to the first embodiment in which all of LCs in a particular LCG have the same priority configuration, in the second and third embodiments, all of LCs in a particular new LCG have the same reliability configuration. That is to say, in the condition that the eNB configures which LCs belong to which new LCG in consideration of reliabilities, the eNB may configure LCs with different reliabilities into the same new LCG. Therefore, the same reliability configuration may mean that there are multiple reliabilities for different LCs contained a particular new LCG. In this sense, the reliability of a particular new LCG means the highest reliability of LC(s) contained in the particular new LCG.

Assuming the priority order for legacy LCG <NUM>-<NUM> is {<NUM>, <NUM>, <NUM>, <NUM>} and the priority order for new LCG <NUM>-<NUM> is (<NUM>, <NUM>, <NUM>, <NUM>}, the BS information is prioritized as shown in <FIG>.

Similar to the first embodiment, in the second and third embodiments, duplicated packet buffer status is only present when there are available duplicated packets for transmission in activated duplicated logical channel in the corresponding new LCG.

<FIG> shows the detailed implementation of BSR MAC CE format containing buffer status of the duplicated packet of the second embodiment. <FIG> shows the detailed implementation of BSR MAC CE format containing buffer status of the duplicated packet of the third embodiment.

Both <FIG> and <FIG> shows that four reserved bits are added at the end of the MAC CE. In the condition that the total number of BS information for legacy LCG and new LCG is odd, four reserved bits are necessary to be added at the end of the MAC CE. The maximum number of each of legacy LCG and new LCG is <NUM>. This means that either the number of the legacy LCG or the number of the new LCG may be <NUM>, <NUM>, <NUM> or <NUM>. Therefore, depending on the number of legacy LCG and new LCG being odd or even, the total number of legacy LCG and new LCG may be odd or even. That is, there are four cases: even + odd -> odd; even + even --> even, odd + odd -> even, odd + even -> odd.

Repeated value of destination index implies the BS information is for duplicated packet buffer status.

Similar to the first embodiment, if the number of bits in the UL grant is not enough for the size of a MAC CE for reporting buffer status, it is preferable to report a truncated BSR containing as much buffer status as possible, unless buffer status for both the LCG and the corresponding new LCG cannot be contained together. The selection of the legacy LCG and new LCG are based on the decreasing priority order of the legacy LCG and the new LCG.

For example, in the example shown in <FIG>, if the full BSR information contains <NUM> bytes, but UL grant is only <NUM> bytes, then based on above rule, the following BS information in the figure is reported.

<FIG> is a schematic flow chart diagram illustrating an embodiment of a method for reporting buffer status. In some embodiments, the method <NUM> is performed by an apparatus, such as the remote unit <NUM>. In certain embodiments, the method <NUM> may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method <NUM> may include <NUM> sending a control element including buffer status information for a logical channel group on which first packets transmit and buffer status information for a corresponding logical channel group on which duplicated packets transmit.

In one embodiment, in the condition that the duplicated packets arrive at a buffer for at least one logical channel contained in the corresponding logical channel group, the buffer status information for the corresponding logical channel group is included. If the buffer status information for the logical channel group and the corresponding logical channel group do not fill full bytes of the control element, reserved bits are added to the control element. The logical channel group and the corresponding logical channel group are associated with the same ProSe destination.

In some embodiment, the control element includes buffer status information for a plurality of the logical channel groups on which the original packets transmit and buffer status information for a plurality of the corresponding logical channel groups on which the duplicated packets transmit. If the number of bits in the UL grant is not enough for the size of the buffer status information for both the plurality of the logical channel groups and the plurality of the corresponding logical channel groups, the control element includes as much buffer status information possible. In particular, if the buffer status information for only the logical channel group or only the corresponding logical channel group can be included in the control element, the buffer status information for both the logical channel group and the corresponding logical channel group are not included in the control element.

In some embodiment, logical channels are grouped into the corresponding logical channel groups according to service priority. The buffer status information for the corresponding logical channel group includes destination index, LCG ID, and buffer size. The destination index of the buffer status information for the corresponding logical channel group is the same as destination index of the buffer status information for the logical channel group with the same priority. The LCG ID of the buffer status information for the corresponding logical channel group is the same as LCG ID of the buffer status information for the logical channel group with the same priority. The buffer size of the buffer status information for the corresponding logical channel group indicates a total amount of duplicated data available for transmission across all of logical channels that have activated duplication in the logical channel group.

In some embodiment, logical channels are grouped into the corresponding logical channel groups according to service reliability. In the control element, the buffer status information for all of the corresponding logical channel groups are positioned after the buffer status information for all of the logical channel groups. In the control element, the buffer status information for the logical channel groups and the corresponding logical channel groups are prioritized according to service priorities of the logical channel groups and the corresponding logical channel groups. In particular, the buffer status information for the logical channel group and the corresponding logical channel group with higher service priority are positioned in front, and the buffer status information for the logical channel group is positioned in front of the buffer status information for the corresponding logical channel group with the same service priority. The buffer status information for the corresponding logical channel group includes destination index, LCG ID, and buffer size. The destination index of the buffer status information for the corresponding logical channel group is the same as destination index of the buffer status information for the logical channel group with the same priority. The buffer size of the buffer status information for the corresponding logical channel group indicates a total amount of duplicated data available for transmission across all of logical channels that activated duplication in the logical channel group. The LCG ID of the buffer status information for the corresponding logical channel group is based on eNB configuration.

In some embodiment, logical channels are grouped into the corresponding logical channel groups according to eNB configuration.

<FIG> a schematic flow chart diagram illustrating a further embodiment of a method <NUM> for reporting buffer status. In some embodiments, the method <NUM> is performed by an apparatus, such as the base unit <NUM>. In certain embodiments, the method <NUM> may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method <NUM> may include <NUM> receiving a control element including buffer status information for a logical channel group on which first packets transmit and buffer status information for a corresponding logical channel group on which duplicated packets transmit.

Claim 1:
A method (<NUM>) of reporting buffer status by a user equipment (<NUM>, <NUM>), the method comprising:
sending (<NUM>) a control element including buffer status information for a logical channel group on which first packets are transmitted and buffer status information for all of the logical channels that have activated packet duplication in the logical channel group;
characterized in that
the control element includes buffer status information for a total amount of data available for transmission of all of the logical channels in the logical channel group on which the original packets transmit and buffer status information for a total amount of duplicated data available for transmission of all of logical channels that have activated duplication in the logical channel group;
wherein logical channels are grouped into the corresponding logical channel groups according to their destinations and in consideration of service reliability configuration.