Apparatus for prioritizing logical channels

Logical channel sorting device

A device used to prioritize logical channels.

Figure 1 shows a Long Term Evolution (LTE) system 100 including a wireless transmit/receive unit (WTRU) 105 and an eNodeB (eNB) 110. Each of the WTRU 105 and the eNB 110 includes a user plane agreement stack with a layer 2 (L2) sublayer. The L2 sublayer includes a packetized data control protocol (PDCP) sublayer 120, a radio link control (RLC) sublayer 125, and a medium access control (MAC) sublayer 130. The protocol stack also includes a physical layer 135. The radio resource control (RRC) sublayer 140 controls each of the PDCP sublayer 120, the RLC sublayer 125, the MAC sublayer 130, and the physical layer 135.

The MAC sublayer 130 supports the following functions:

1) Mapping between logical channels and transmission channels;

2) Multiplex the MAC service data unit (SDU) from one or different logical channels to the transport block (TB) delivered to the physical layer 135 on the transmission channel;

3) Demultiplex the MAC SDU from one or different logical channels of the TB, and deliver the TB from the physical layer 135 on the transmission channel;

4) Dispatch information report;

5) Error correction through hybrid automatic transmission request (HARQ);

6) Priority processing between WTRUs using dynamic scheduling;

7) Priority processing between logical channels of the WTRU;

8) Prioritization of logical channels; and

9) Transmission format selection.

One function of the MAC sublayer 130 in the WTRU 105 is logical channel prioritization. Figure 2 shows the available uplink transmission channels such as the random access channel (RACH) 205 and the uplink shared channel (UL-SCH) 210, and the available uplink transmission channels such as the common control channel (CCCH) 215, the dedicated control channel ( DCCH) 220 and Dedicated Service Channel (DTCH) 225 available uplink logical channels. The MAC sublayer 130 may receive MAC SDUs (ie, RLC protocol data units (PDU)) from different logical channels from the RLC sublayer 125. The MAC sublayer 130 then multiplexes these MAC SDUs onto the transmission channel (e.g., UL SCH 120).

The MAC SDU is prioritized and selected from different logical channels. The logical channel prioritization process can be applied when performing a new MAC transmission. The RRC sublayer 140 can control the scheduling of uplink data by giving each logical channel a priority, where a larger priority value indicates a lower priority level. In addition, each logical channel is configured to have a priority bit rate (PBR) and optionally a maximum bit rate (MBR).

The uplink (UL) grant provides the channel resource characteristics that can be used for data transmission on the uplink. UL authorization is a 20-bit field used to indicate fixed-size resource block allocation, modulation and coding method (MCS), UL delay, and transmission power control (TPC). The UL grant is sent from the eNB 110 to the WTRU 105 in the downlink (DL) to inform the WTRU 105 of the number and type of channel resources used by the WTRU 105 for UL transmission.

The logical channel prioritization process assists the WTRU to provide logical channels in the following order:

1) Logical channels are provided in decreasing priority order of reaching their configured PBR.

2) If any resources still exist, the logical channels are provided in decreasing priority order to reach their configured MBR. If the MBR is not configured, the logical channel is provided until one of the material or UL authorization for the logical channel is first used up.

3) WTRUs equally provide logical channels configured to have the same priority.

4) MC control elements (except padding BSR) used for the basic symbol rate (BSR) have a higher priority than the priority of the user plane logical channel.

The WTRU has an uplink rate control function that manages uplink resource sharing between radio bearers. RRC controls the uplink rate control function by giving each bearer a priority and priority bit rate (PBR). In addition, MBR is also configured for each total bit rate (GBR) bearer. The value signaled may be independent of the value signaled to the eNB via S1.

The uplink rate control function ensures that the WTRU provides its radio bearers in the following order:

1) All radios are carried in a decreasing priority order to reach their PBR; and

2) All radios are carried in a decreasing priority order to reserve the resources allocated by the authorization and ensure that the function does not exceed the MBR.

If PBR is all set to 0, skip step 1) and provide radio bearers in strict priority order. The WTRU maximizes the transmission of higher priority data. By limiting the total authorization to the WTRU, the eNB can ensure that the total MBR (AMBR) will not be exceeded. If multiple radio bearers have the same priority, the WTRU can provide these radio bearers equally.

Since the operator owns the resources, the scheduling and resource allocation of radio resources occurs in the MAC sublayer 130 in the eNB 110. However, the MAC sublayer 130 in the WTRU 105 provides the eNB 110 with information such as quality of service (QoS) requirements and WTRU radio conditions (identified by measurement) as input to the scheduling process at the eNB H10T.

Initially, note that input parameters can be specified. It is also possible to specify the output limit of the WTRU (the output of the MAC sublayer 130P scheduler). However, imperative WTRU operation is not required.

For the specification of input parameters, the token bucket mode can be used. PBR/MBR is the "scepter rate". In this mode, there is a "token bucket size" parameter, but it is not determined whether this parameter is obtained by the WTRU from, for example, a staking rate or a fixed size, or whether it needs to be signaled explicitly by the eNB.

The token bucket is a control mechanism used to indicate when to transmit services. The "bucket" in the data transmission environment refers to a register that holds the total network traffic to be transmitted as a way of controlling traffic. The bucket (ie, the register) includes a token, and the token represents a traffic volume in bytes or packets of a predetermined size that is allowed to be transmitted by the sender. The amount of available tokens can be viewed as "credits" that are buffered when data needs to be transferred. When the sender runs out of "credits" (that is, the tokens in the bucket), the sender is not allowed to send any more traffic. PBR/GBR should not limit the reported register status. The impact of MBR on the status report of the register is uncertain.

The token bucket mode is used to describe the rate calculation, so each logical channel will have a token bucket associated with it, and the token bucket is associated with PBR and MBR. The rate at which the token is added to the bucket is PBR and MBR respectively. The size of the token bucket cannot exceed a certain maximum value.

The following provides possible descriptions of rate calculations or equivalent token bucket calculations. If it is acceptable to explicitly describe the WTRU's behavior, then (scepter) credits can be used. By way of example, for each increment of Tj, there is one PBR for each bearer j, and the PBR credit related to bearer j is incremented by a value of Tj×PBRj. If the bearer also has MBR, the MBR credit associated with bearer j is incremented by the value Tj×MBRj. If a higher limit is set for the maximum PBR and/or MBR credits carried, if the accumulated value exceeds the maximum value, they are set equal to the maximum value.

At each scheduling occasion (ie, transmission time interval (TTI)), the WTRU is allowed to transmit new data, selecting data from the highest priority bearers with non-empty register status and non-zero PBR credits. The WTRU may add data to the transmission block, the data being equal to the size of the register, the size of the PBR credit, or the available capacity of the transmission block, whichever is smaller. The amount of PBR credit and the amount of MBR credit are decremented according to the amount of allocated data.

If the PBR credits of all bearers are zero and there is still space in the transmission block, the scheduler receives data from the highest priority bearer with buffered data. The scheduler receives as much data as the available space in the transport block or the MBR credit of the WTRU, whichever is smaller. The amount of MBR credit is decreased according to the amount of data received. The received data is combined before the data is obtained from the RLC sublayer.

Rate calculation, or equivalent token bucket calculation can also be described. At each TTI boundary where the HARQ entity requests a new transmission, the WTRU performs the following operations: For each logical channel sorted in decreasing priority order, perform the following: -if ((PBR token bucket UL grant) and ( The amount of buffered data authorized by UL for transmission))-provides a logical channel of bytes up to MIN (the amount of buffered data used for transmission, the maximum output rate of PBR).

-Otherwise-if (PBR token bucket 0)-additional token allowed = MIN (MAX (0, UL authorization-PBR token bucket), 0.5 × PBR bucket size)-otherwise-additional token allowed = 0-Provide a logical channel for x bytes, where x is between 0 and MIN (UL authorization, PBR token bucket + allowed extra token, amount of data buffered for transmission, PBR maximum output rate) bits Between tuples. The value of x is execution-related, (for example, when selecting the value of x, the WTRU should consider various factors such as SDU segmentation, fair provision of two logical channels with the same priority, etc.).

-If the number of bytes is provided, the UL authorization will be decremented according to the number of bytes provided.

-If there is a byte quantity provided, the PBR token bucket will be decremented according to the byte quantity provided.

-If the UL authorization is greater than 0, for each logical channel sorted in decreasing priority order, the following is performed:-If the MBR token bucket has been configured for the logical channel,-if ((MBR token bucket UL authorization ) And (the amount of buffered data authorized by UL for transmission))-provide the logical channel of the byte that reaches MIN (the amount of buffered data for transmission, the maximum output rate of MBR);-otherwise-if ( MBR token bucket 0)-allowed additional token = MIN (MAX (0, UL authorization-MBR token bucket), 0.5 × MBR bucket size)-otherwise-allowed additional token = 0-provided for x The logical channel of the byte, where x is between 0 and the byte of MIN (UL authorization, MBR token bucket + allowed extra token, amount of data buffered for transmission, MBR maximum output rate). The value of x is execution dependent (for example, when choosing the value of x, the WTRU should consider various factors such as SDU segmentation, fair provision of two logical channels with the same priority, etc.)-otherwise-provide up to MIN (UL Authorization, the amount of data buffered for transmission) of the logical channel;-if there is a provided amount of bytes, the UL authorization is decremented according to the provided amount of bytes; and-if so In the case of the number of bytes, the MBR token bucket is decremented according to the number of bytes provided.

The WTRU will equally provide logical channels configured to have the same priority.

MAC PDU and MAC control elements

Figure 3 shows a MAC PDU 300, which includes a MAC header 305, and may include MAC SDUs 310 and 315, MAC control elements 320 and 325, and padding 330. Both the MAC header 305 and the MAC SDU 310 and 315 have variable sizes.

The header of MAC PDU 300 includes one or more MAC PDU sub-headers 335, 340, 345, 350, 355, and 360, each of which corresponds to MAC SDU 310 or 315, MAC control element 320 or 325, or padding 330.

The MAC sublayer can generate MAC control elements, such as register status report control elements. The MAC control element is identified by a specific value for logical channel identification (LCID), as shown in Table 1 below. The index 00000-yyyyy corresponds to the actual logical channel with the corresponding RLC sublayer, and the remaining value can be used for other purposes, such as identifying MAC control elements (eg, register status report), or filling.

<tables><img file="TWM358487U_D0001.tif" /></tables>

<tables><img file="TWM358487U_D0002.tif" /></tables>

RLC

The main services and functions of the LTE RLC sublayer include:

1) Support the transmission of higher-layer PDUs in Acknowledgment Mode (AM) or Unacknowledged Mode (UM);

2) Transparent mode (TM) data transmission;

3) Error correction through ARQ (CRC check provided by the physical layer, CRC is not required at the RLC layer);

4) Segmentation according to TB size: Only RLC SDU is not completely suitable for TB, RLC SDU is segmented into RLC PDUs of different sizes, excluding any padding;

5) Resegmentation of the PDU that needs to be retransmitted: If the retransmitted PDU is not completely suitable for the new TB for retransmission, the RLC PDU is re-segmented;

6) There is no limit to the number of re-segmentation;

7) Connection of SDUs carried by the same radio;

8) Sequential delivery of higher layer PDUs except for handover (HO) in the uplink;

9) Repeat testing;

10) Agreement error detection and recovery;

11) Flow control (FFS) between eNB and WTRU;

12) SDU abandonment; and

13) Reset.

RLC supports three operating modes: AM (Answer Mode), UM (Unanswered) Mode, and TM (Transparent Mode) and generates control PDUs, such as status PDUs generated by AMRLC entities.

When considering the control traffic and the logical channel corresponding to the Signaling Radio Bearer (SRB), it is expected to provide an enhanced L2 uplink channel prioritization and rate control method for minimizing padding.

An apparatus for prioritizing logical channels when performing new transmissions is disclosed. Assign logical channel resources to multiple logical channels for available materials. In the register (ie bucket) associated with a specific logical channel in the logical channel, the MBR credit (ie token) is decremented according to the size of the MAC SDU. The MBR credit can have a negative value. If any allocated channel resources still exist, logical channels must be provided in decreasing priority order until the data is exhausted. If the entire RLC SDU fits the remaining resources, the RLC SDU is not segmented. The MAC SDU does not include the MAC PDU header and MAC padding. At each scheduling occasion when the WTRU is allowed to transmit new data, the WTRU selects data from the radio bearers in the highest priority order. The radio bearers may have non-empty register status and non-zero priority bit rate (PBR) credits. The WTRU may add data to the transmission block, the data in the transmission block is equal to the size of the scratchpad, the size of the PBR credit, or the available capacity of the transmission block, whichever is smaller.

The disclosed method and device maximize the use of available channel resources (ie, maximize UL authorization). Therefore, if there are still available resources after the strict priority order and the specific priority and maximum data rate restrictions are met, the logical channel is provided again based on the strict priority order without restricting the allocation of specific bucket sizes (for example, MBR credits are allowed Is negative) to use the available capacity. More precisely, the allocation is limited by the amount of data transmitted by the logical channel or the size of the UL grant allocated to the logical channel.

The WTRU decrements the PBR credits and MBR credits according to the amount of allocated data, and repeats this step if there is space in the transmission block. This step can be repeated for radio bearers according to the priority of the radio bearers.

A method and device for bit rate control and token/credit bucket update in the WTRU are also disclosed. The MAC entity in the WTRU can update the token bucket associated with the data protocol data unit (PDU) instead of the control PDU. The WTRU may update the token bucket at different times and in various measured quantities.

The term "wireless transmit/receive unit (WTRU)" mentioned below includes but is not limited to user equipment (UE), mobile station, fixed or mobile subscriber unit, pager, cellular phone, personal digital assistant (PDA), computer, or Any other type of user equipment operating in a wireless environment. The term "base station" mentioned below includes but is not limited to node B, site controller, access point (AP), or any other type of peripheral equipment.

In the content of this disclosure, the RLC PDU is equivalent to the MAC SDU, and updating the token bucket (or credit amount) generally involves subtracting the token (credit amount) amount from the bucket, so that the amount corresponds to the packet size. The token bucket or credit calculation is equivalent to the data rate calculation or the rate control calculation. Although the method and device use the token bucket mode, the execution of the data rate control calculation logic may not use the token bucket method.

Enhanced uplink channel prioritization and rate control functions

The WTRU's transmitting MAC entity may perform another round of prioritization proposed in the following method (for example, in the case of restricted authorization (ie, when the WTRU's available data may exceed the authorized amount)) to prevent filling.

At each scheduling opportunity or TTI, where the WTRU is allowed to transmit new data, the WTRU selects data from the highest priority load with non-empty register status and non-zero PBR credits. The WTRU may also add data to the transmission block, the data being equal to the size of the register, the size of the PBR credit, or the available capacity of the transmission block, whichever is smaller. The amount of PBR credit and the amount of MBR credit are decremented according to the amount of allocated data. Although there is still space in the transport block, this step can be repeated for the bearer according to the priority of the bearer.

If the PBR credits of all bearers are 0 (or negative) and there is still space in the transmission block, the scheduler receives data from the highest priority bearer with buffered data. The scheduler receives data up to the size of the available space in the transport block or the MBR credit of the WTRU, whichever is smaller. The amount of MBR credit is decreased according to the amount of data received. The data received from the above steps are combined before the data is obtained from the RLC. Although there is still space in the transport block, this step can be repeated for the bearer according to the priority of the bearer. If the MBR of all bearers is 0 (or negative) and there is still space in the transmission block, the scheduler receives data from the highest priority bearer with buffered data. The scheduler receives data up to the size of the available space in the transmission block. The amount of MBR credit is decreased according to the amount of data received (negative or more negative numbers are allowed). Here, the data received before the data is obtained from the RLC are combined.

This method can be executed in combination with other prioritization methods, and it can be executed even if MBR is not configured for some logical channels. If the MBR credit is 0, the MBR bucket is not considered.

This method is useful in restricting authorization situations, for example, if all other bearers reach or exceed their MBR, or if there is no other available data in some bearers, and there are available data in other bearers that exceed their MBR.

The method can be changed to compare the MBR credit with a non-zero threshold value. For example, if the MBR credits of all bearers are 0 (or negative) and there is still space in the transmission block, the scheduler receives data from the highest priority bearer with buffered data. The scheduler receives data up to the size of the available space in the transmission block or the difference between the "MBR credit" and the "maximum allowable negative MBR bucket size", whichever is less. MBR credits are decremented according to the amount of data received (thus allowing negative or more negative numbers). The data received before the data is obtained from the RLC are combined.

If there are not enough credits or tokens to fill the transmission block with data, maximize the transmission by allowing the possibility of receiving data from logical channels with insufficient tokens or credits as a final prioritization or rate control step Utilization of blocks (and MAC padding should be minimized) instead of performing padding.

The uplink rate control function ensures that the WTRU provides its radio bearers in the following order:

1) All radios are carried in a decreasing priority order to reach their PBR;

2) All bearers are used in the decreasing priority order to reserve the resources allocated by the authorization and ensure that the function does not exceed the MBR;

3) All bearers are used in a decreasing priority order to reserve resources allocated by authorization and the function allows to exceed the MBR (to minimize/prevent padding in the transport block).

Alternatively, the logical channel prioritization process ensures that the WTRU provides logical channels in the following order:

1) All logical channels are provided in a decreasing priority order that reaches their configured PBR;

2) If any resources still exist, all logical channels are provided in a strict decreasing priority order up to their configured MBR. If MBR is not configured, the logical channel is provided until one of the material or UL authorization for the logical channel is first used up; and

3) If any resources still exist, provide all logical channels in a strictly decreasing priority order that reaches one of the following two variables: until the material or UL authorization for that logical channel is exhausted; or until it is used The data on the logical channel or the difference between the "MBR token bucket size" and the "maximum allowable negative MBR bucket size" or the UL authorization is exhausted.

Enhanced uplink channel prioritization and rate control of control PDUs and control elements

RLC can generate control PDUs, such as RLC status PDUs. Moreover, MAC can generate control elements.

Higher-level control PDUs, such as PDCP control PDUs, PDCP status reports, robust header compression (ROHC) feedback, etc., can be mapped to (or encapsulated into) RLC control PDUs instead of being mapped to (or encapsulated into) RLC Data PDU. This may allow higher layer control PDUs, such as PDCP control PDUs, to be differentiated at lower layers (i.e. at RLC and MAC), and thereby allow them to receive improved processing (e.g. QoS, faster transmission, etc.). Due to the lack of tokens or credits, the WTRU will not restrict the transmission of RLC control PDUs.

Always prioritize control of data

The WTRU may not check/compare/check the token/credit bucket level used for RLC control PDU or MAC control element. The WTRU's transmit MAC entity will perform additional steps to prevent stuffing.

In another step, at each scheduling opportunity (TTI) that the WTRU is allowed to transmit, the WTRU selects data from the highest priority bearer with control PDUs (or control elements). The WTRU may add data to the transmission block. The data is equal to the size of the control PDU or the available capacity of the transmission block, whichever is less. The amount of PBR credit and the amount of MBR credit are decremented according to the amount of allocated data. In an alternative embodiment, in the case of the control PDU, the PBR credit and the MBR credit are not decremented. Although there is still space in the transport block, this step can be repeated for the bearer according to the priority of the bearer.

If there is still space in the transport block, the WTRU selects data from the highest priority bearer with non-empty register status and non-zero PBR credits. The WTRU may add data to the transmission block, the data being equal to the size of the register, the size of the PBR credit, or the available capacity of the transmission block, whichever is smaller. The amount of PBR credit and the amount of MBR credit are decremented according to the amount of allocated data. Although there is still space in the transport block, this step can be repeated for the bearer according to the priority of the bearer.

If the PBR credits of all bearers are 0 and there is still space in the transmission block, the scheduler receives data from the highest priority bearer with buffered data. The scheduler receives data up to the size of the available space in the transport block or the MBR credits of the WTRU, whichever is smaller. The amount of MBR credit is decreased according to the amount of data received. The data received before the data is obtained from the RLC are combined. Although there is still space in the transport block, this step can be repeated for the bearer according to the priority of the bearer.

The WTRU may prioritize RLC control PDUs or MAC control elements or collectively control PDUs over data PDUs. This prevents delays or extreme lack of control information due to high-priority data traffic.

Prioritize data control, but only reach a certain amount

The previous method prioritizes data control. However, this may mean that if there are a large number of control PDUs on the "lower priority" logical channels, some "higher priority" logical channels may be delayed.

Limit the size of the transfer block that can be used for control

The WTRU can commit to or ensure that a part of the transmission block is used for data traffic by limiting the size of the transmission block that can be used for control traffic. This restriction can be implemented in a variety of ways, such as specifying the maximum proportion of TB used for control (in percentage, or in the form of original size, or in any other form). This ratio can be configured through the RRC Information Element (IE) carried in any RRC message.

Limit the rate of control traffic

The WTRU can measure and control the rate of control PDUs (or control elements). New parameters like PBR/MBR can be used, such as controlling BR (bit rate). The WTRU may limit the number of control PDUs sent with the highest priority to the amount controlled by the control BR. However, this cannot prevent the control PDU from being sent on the logical channel when the logical channel is scheduled (in a round of PBR or MBR). The priority bit rate used for control can be configured through the RRC IE carried in any RRC message (for example, for RLC control PDU or MAC control element).

In addition, it is possible to further distinguish and specify two control rates: RLC control bit rate (RCBR) and MAC control bit rate (MCBR). Similarly, these parameters can be configured through the RRC IE carried in any RRC message.

Avoid segmentation for control

In order to quickly transmit/receive RLC control PDUs or MAC control elements (in a TTI), usually it is not desired to segment control information, such as RLC control PDUs or MAC control elements. The RLC segmentation function is not applied to the RLC control PDU (for example, status PDU) and the MAC segmentation function is not defined.

When MAC uses token/credit calculation for control, when token/credit is insufficient, MAC can receive all control PDUs or control elements even when MAC has insufficient token/credit, instead of allowing token/ The credit amount becomes negative because the control cannot be segmented.

This can be implemented as an optional case, that is, only negative buckets are allowed if used for control purposes. Alternatively, this can also be performed as part of allowing overall negative tokens (due to control or data).

Enhanced uplink channel prioritization for logical channels corresponding to signalling (e.g. RRC) radio bearers

Regarding logical channels corresponding to signaling radio bearers (SRBs) (eg, SRB0, SRB1, SRB2), the logical channels may have absolute priority higher than all other logical channels corresponding to the data RB. This can be achieved in two ways:

1) Change the logical channel prioritization function to always prioritize SRB (that is, there is no need to configure PBR/MBR for SRB); or

2) Configure the PBR/MBR for SRB to the maximum allowed.

Using the uplink rate control function, the WTRU provides its radio bearers in the following order:

1) All signaling radio bearers with decreasing priority (optional: may reach a specific rate);

2) All radios are carried in a decreasing priority order to reach their PBR;

3) All radio bearers in decreasing priority order are used to maintain the resources allocated by the authorization and function to ensure that the MBR is not exceeded.

Alternatively, the logical channel prioritization process helps the WTRU to provide logical channels in the following order:

1) Provide all logical channels corresponding to SRB (or RRC control information) in a decreasing priority order (optional: the configured bit rate may be reached);

2) Provide all logical channels up to the configured PBR in decreasing priority order;

3) If any resources still exist, provide all logical channels that reach their configured MBR in strict decreasing priority order. If the MBR is not configured, the logical channel is provided until one of the material or UL authorization for the logical channel is first used up.

Alternative architecture

Currently, token/credit calculations (ie, rate control or bit rate calculations for PBR and MBR) are performed in the transmitting MAC entity. In an alternative architecture, the WTRU performs rate control calculations in the transmitting RLC entity. The transmitting RLC entity performs PBR and/or MBR calculation (for example, PBR/MBR token/credit bucket calculation).

In another alternative architecture, the WTRU performs rate control calculations in the transmitting PDCP entity. The transmitting PDCP entity performs PBR and/or MBR calculation (for example, PBR/MBR token/credit bucket calculation).

Selection update of token bucket: exclude control PDUs (or usually specific types of PDUs) from PBR and MBR calculations

The WTRU may not consider the control PDU generated by the RLC or MAC when performing its bit rate calculation or equivalently when performing the token bucket calculation or credit calculation. The WTRU will evaluate whether the packet is control or data. If it is data, the WTRU will update the relevant token bucket. If it is control, the WTRU will not update the relevant token bucket.

The MAC layer of the WTRU can perform specified operations, optionally with the help of information provided by the RLC. However, other layers in the WTRU (e.g., RLC or PDCP) can also incorporate this operation.

Exclude RLC control PDU from PBR and MBR calculation

RLC can generate control PDUs, such as RLC status PDUs. Higher-level control PDUs, such as PDCP control PDUs, PDCP status reports, robust header compression (ROHC) feedback, etc., can be mapped to (or encapsulated into) RLC control PDUs instead of being mapped to (or encapsulated into) RLC data PDUs . This may allow higher layer control PDUs, such as PDCP control PDUs, to be differentiated at lower layers (i.e., at RLC and MAC) and allow them to receive improved processing (e.g., quality of service (QoS), faster transmission, etc.).

Regarding the RLC PDU from the transmitting RLC entity to the transmitting MAC entity, the transmitting MAC entity can evaluate whether the RLC PDU (ie, MAC SDU) is a control PDU or a data PDU. This can be based on information provided from the RLC entity to the MAC entity (e.g. primitive/signal), or based on checking the D/C field of the RLC PDU header. If it is a data PDU, the transmitting MAC entity will update the relevant token bucket (that is, the transmitting MAC entity will affect the PBR and/or MBR calculation). If it is a control PDU, the transmitting MAC entity will not update the relevant token bucket (that is, the transmitting MAC entity will not affect the PBR and/or MBR calculation).

Exclude RLC retransmitted PDUs from PBR and MBR calculations

For example, when the HARQ process fails, or when the RLC receives an RLC status report with a negative response, the RLC can retransmit the data PDU through ARQ. Therefore, usually the transmitting RLC entity can submit/provide the RLC data PDU or the retransmitted RLC data PDU to the transmitting MAC entity.

Regarding the RLC PDU from the transmitting RLC entity to the transmitting MAC entity, the transmitting MAC entity can evaluate whether the RLC PDU (ie, MAC SDU) is a control PDU or a data PDU. The determination may be based on information provided from the RLC entity to the MAC entity (for example, primitives/signals) or based on checking the D/C field of the RLC PDU header. If the RLC PDU is data, the transmitting MAC entity will also evaluate whether the RLC data PDU is a new PDU or a retransmitted PDU. The determination can be based on information provided from the RLC entity to the MAC entity (e.g., primitives/signals) or based on checking one or more fields of the RLC PDU header (e.g., re-segmentation flag, or PDU segment number (SN), Or segmented offset or any other field).

If the PDU is new data, the transmitting MAC entity will update the relevant token bucket (that is, the transmitting MAC entity will affect the PBR and/or MBR calculation). If the PDU is retransmitted data, the transmitting MAC entity will not update the relevant token bucket (that is, the transmitting MAC entity will not affect the PBR and/or MBR calculation). The term RLC PDU includes PDU and PDU segment. For PBR/MBR calculation, the retransmitted PDU or PDU segment will not be counted or considered.

Exclude MAC control elements and MAC padding from PBR and MBR calculations

The MAC can generate control elements, such as register status reports. MAC can also generate padding.

For the MAC control element, the transmitting MAC entity will not update the relevant token bucket (that is, the transmitting MAC entity will not affect the PBR and/or MBR calculation). For MAC filling, the transmitting MAC entity will not update the relevant token bucket (that is, the transmitting MAC entity will not affect the PBR and/or MBR calculation).

How much packet size should be used to update the bucket?

In order to update the token (credit) bucket, for example, by subtracting some tokens/credits, the transmission MAC entity of the WTRU can decrement the token/credit bucket of the logical channel by using:

1) The size of the MAC SDU (that is, excluding the MAC PDU header and MAC padding);

2) MAC PDU size (including MAC PDU header, PDU payload and MAC padding);

3) The size of MAC PDU except MAC padding (including MAC PDU header and PDU payload);

4) The size of the MAC PDU except the MAC PDU header (including the MAC PDU payload and MAC padding);

5) The size of the RLC PDU (that is, including the RLC PDU header and PDU payload);

6) The size of RLC PDU except RLC padding (including RLC header and RLC payload except RLC padding);

7) The size of RLC PDU payload (including RLC payload);

8) The size of RLC PDU payload except RLC cautious charging (including RLC payload except RLC filling);

9) PDCP SDU size;

10) PDCP PDU size (that is, including PDCP PDU header and PDU payload);

11) The size of the PDCP PDU before header compression is applied (that is, including the PDCP PDU header and PDU payload before header compression); or

12) The size of the PDCP PDU before applying security (ie, encryption and/or integrity protection) (ie, including the PD-CP PDU header and PDU payload before encryption and/or integrity).

In order to determine the size, the higher transmission sublayer (such as RLC or PDCP) can send size information to the transmitting MAC entity, and the MAC can use the information.

Inter-layer communication and signaling can be used.

Alternatively, the MAC entity checks higher layer headers (for example, RLC or PDCP headers) and extracts the size information.

Events and triggers used to update the bucket

The time or event when the token/credit bucket is updated may have an impact on system performance. The WTRU's transmitting MAC entity may decrement the token/credit bucket of the logical channel at the following events/times:

13) The event/time when the transmission MAC entity multiplexes the MAC SDU to the MAC PDU;

14) The event/time when the transmission of the MAC entity completes the establishment of the MAC PDU;

15) The event/time when the transmitting MAC entity delivers a new MAC PDU (ie, a new HARQ PDU) to the physical layer (or HARQ);

16) The event/time when the transmitting MAC entity receives the HARQ response for MAC PDU (ie, for HARQ PDU);

17) The event/time when the HARQ process (carrying MAC SDU/PDU) is completed/end (successful or unsuccessful); or

18) The event/time when the transmitting MAC entity receives the RLC response for the RLC PDU.

In order to be more accurate and to prevent the waste/loss of credits used for PDUs that have not been transmitted, the token is subtracted from the bucket after the HARQ response is received.

Figure 4 is a block diagram of a WTRU 400 using a logical channel MBR rate credit register that can store negative MBR credit values. The WTRU 400 includes an antenna 405, a transmitter 410, a receiver 415, a processor 420, and at least one logical channel MBR credit register 425. The register 425 buffers the MBR credit and the MBR credit may have a negative value. The processor 420 is configured to allocate logical channel resources to multiple logical channels with available data, and store the maximum bit rate (MBR) credits in the temporary memory 425 related to a specific one of the logical channels according to the media storage. The size of the control (MAC) service data unit (SDU) is decremented. If any allocated channel resources still exist, logical channels are provided in decreasing priority order until the data is exhausted. Alternatively, the logical channels are provided in decreasing priority order until the UL grant is exhausted.

Figure 5 is a flowchart of the logical channel prioritization process 500 when the WTRU 400 of Figure 4 performs a new transmission. In step 505, logical channel resources are allocated to multiple logical channels for available materials. In step 510, the amount of MBR credit in the temporary memory associated with a specific one of the logical channels is decremented according to the size of the MAC SDU.

The MAC SDU corresponds to the MAC payload to be carried in a specific transport block (ie, the available space allocated to the WTRU on the transport block in a specific TTI). It is possible to provide only logical channels up to the size of the MAC SDU, and the MAC SDU will be transmitted to the transport block. Thus, if the "credit" allocated for a specific logical channel is greater than the size of the MAC SDU, the credit is decremented by the size of the MAC SDU until the credit is used up.

By using the available space in the configured transport block in the most efficient way possible, the allocated resources can be maximized. Thus, since the capacity of one or more logical channels is delivered through the RLC SDU, the entire RLC SDU can be included in the RLC PDU even if there are not enough available MBR credits/tokens (ie, the allowable MBR credits become negative) In order to avoid fragmentation and delays.

The MAC SDU does not include the MAC PDU header and MAC padding. The MBR credit can have a negative value. In step 515, if any allocated resources still exist, logical channels are provided in decreasing priority order until the materials are exhausted. Alternatively, the logical channels are provided in decreasing priority order until the UL grant is exhausted. If the entire RLC SDU fits the remaining resources, there is no need to segment the RLC SDU.

Although the features and elements of this creation are described above in a specific combination, each feature or element can be used alone without the other features and elements of the preferred embodiment, or with or without other features or elements. Used in various situations where features and elements are combined. The method or flowchart provided herein can be implemented in a computer program, software, or firmware executed by a general-purpose computer or processor, where the computer program, software, or firmware is contained in a computer-readable storage medium in a tangible manner of. Examples of computer-readable storage media include read-only memory (ROM), random access memory (RAM), scratchpads, cache memory, semiconductor storage devices, magnetics such as internal hard drives and removable disks Media, magneto-optical media, and optical media such as CD-ROM discs and digital versatile discs (DVD).

For example, suitable processors include: general-purpose processors, special-purpose processors, traditional processors, digital signal processors (DSP), multiple microprocessors, one or more microprocessors related to the DSP core, control Device, microcontroller, dedicated integrated circuit (ASIC), field programmable gate array (FPGA) circuit, any kind of integrated circuit (IC) and/or state machine.

The software-related processor can be used to implement a radio frequency transceiver for use in a wireless transmit and receive unit (WTRU), user equipment (UE), terminal, base station, radio network controller (RNC), or any host computer use. WTRU can be used in combination with modules implemented in hardware and/or software, such as cameras, camera modules, video phones, speaker phones, vibration devices, speakers, microphones, TV transceivers, hands-free headsets, keyboards, Bluetooth<img file="TWM358487U_D0003.tif" />Module, frequency modulation (FM) wireless unit, liquid crystal display (LCD) display unit, organic light emitting diode (OLED) display unit, digital music player, media player, video game console module, Internet browser And/or any wireless local area network (WLAN) module or ultra-wideband (UWB) module.

<p>100. . . Long Term Evolution System</p><p>MAC. . . Media access control</p><p>PDCP. . . Packet Data Control Protocol</p><p>RLC. . . Non-segmented radio link control</p><p>RRC. . . Radio resource control</p><p>WTRU, 105, 400. . . Wireless transmitting/receiving unit</p><p>CCCH. . . Public control channel</p><p>DCCH. . . Dedicated control channel</p><p>DTCH. . . Dedicated business channel</p><p>RACH. . . Random access channel</p><p>UL-SCH. . . Uplink shared channel</p><p>LCID. . . Logical channel identification</p><p>SDU. . . Service Information Unit</p><p>300. . . Media Access Control Protocol Data Unit</p><p>405. . . antenna</p><p>MBR. . . Maximum bit rate</p>

A more detailed understanding can be obtained from the following description of the implementation manner given by way of example, and can be understood in conjunction with the accompanying drawings, in which:

Figure 1 shows LTE user plane protocol stacking;

Figure 2 shows a diagram of uplink MAC mapping/multiplexing;

Figure 3 shows a MAC PDU including MAC header, MAC control element, MAC SDU and padding;

Figure 4 is a block diagram of a WTRU using a logical channel MBR rate credit register capable of storing negative MBR credit values;

Figure 5 is a flowchart of the logical channel prioritization process applied when the WTRU of Figure 4 performs a new transmission.