Method executed by user equipment and user equipment

Abstract

The invention provides a method executed by user equipment (UE) and the UE. The method executed by the UE comprises the following steps: a PDCP entity receives a request for reconstructing a packet data convergence protocol PDCP from an upper layer; and if the PDCP entity receiving the request is a transmit PDCP entity, transmitting the request to the PDCP entity, the UE determines whether a radio bearer (RB) to which the PDCP entity belongs is a multi-mode data radio bearer (DRB) or a multi-mode radio bearer associated with at least one radio link control (UM) RLC entity in an unacknowledged mode, or a multi-mode radio bearer associated with at least one acknowledgement mode radio link control (AM) RLC entity, the multi-mode DRB being a DRB associated with at least one UM RLC entity and at least one AM RLC entity.

Description

Technical Field

[0001] This disclosure relates to the field of wireless communication technology, and more specifically, to a method performed by a user equipment and a user equipment. Background Technology

[0002] Currently, one of the research goals of extended reality (XR) in 3GPP is to improve effective support for XR applications with multi-modal inter-dependencies and multiple QoS flows, aiming to achieve synchronization or coordination between data flows while meeting multi-modal QoS requirements. One feasible approach is to associate multiple radio link control entities (RLC entities) within the same radio bearer (RB). To meet different QoS requirements, these RLC entities can be configured in different modes. In implementation, such RLC entities are associated with the same PDCP entity, thereby enabling collaborative management of data flows. For PDCP entities with RLC entities associated with different modes, how to reconstruct and recover data is a problem that needs to be solved. Summary of the Invention

[0003] To address the aforementioned problems, the present invention provides a method for user equipment execution and a user equipment.

[0004] According to one aspect of the present invention, a method executed by a user equipment (UE) is provided, comprising: a PDCP entity receiving a request from an upper-layer reconstructing packet data convergence protocol (PDCP); and, if the PDCP entity receiving the request is a transmitting PDCP entity, the UE determining whether the radio bearer (RB) to which the PDCP entity belongs is a multimode data radio bearer (DRB), or a multimode radio bearer associated with at least one unacknowledged mode radio link control (UM RLC) entity, or a multimode radio bearer associated with at least one acknowledged mode radio link control (AM RLC) entity, wherein the multimode DRB is a DRB associated with at least one UM RLC entity and at least one AM RLC entity.

[0005] In the method executed by the user equipment UE described above, preferably, when the user equipment UE determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one UM RLC entity, for each PDCP service data unit (PDCP SDU) that has been associated with a PDCP sequence number, if the user equipment UE determines that the PDCP protocol data unit (PDCP PDU) corresponding to the PDCP SDU has not yet been delivered to the lower-layer UM RLC entity, then the user equipment UE considers that the PDCP SDU was received from the upper layer of PDCP and transmits the PDCP SDU.

[0006] In the method executed by the user equipment UE described above, preferably, when the user equipment UE determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one AM RLC entity, if the PDCP entity corresponding to the multi-mode DRB or the multi-mode radio bearer has been suspended or paused during or before the PDCP reconstruction, then for each PDCP service data unit (PDCP SDU) that has been associated with a PDCP sequence number, if the user equipment UE determines that the PDCP protocol data unit (PDCP PDU) corresponding to the PDCP SDU has not yet been successfully confirmed by the lower-layer AM RLC entity, then the user equipment UE considers the PDCP SDU to have been received from the upper layer of PDCP and transmits the PDCP SDU.

[0007] In the method performed by the user equipment (UE) described above, preferably, the UE performs one or more of the following operations on each PDCP SDU during transmission:

[0008] - Start a timer for the PDCP SDU;

[0009] - Associate a count value COUNT with the PDCP SDU;

[0010] - Perform header compression on the PDCP SDU;

[0011] - Perform uplink data compression on the PDCP SDU;

[0012] - The PDCP SDU is protected for integrity and encrypted using the value of the state variable TX NEXT;

[0013] - Set the value of the PDCP sequence number of the PDCPPDU corresponding to the PDCP SDU. This value can be obtained based on the state variable TX NEXT.

[0014] - Update the value of the state variable TX NEXT by incrementing its value by 1;

[0015] - Submit the processed PDCP PDU to the corresponding RLC entity.

[0016] In the method executed by the user equipment UE described above, preferably, when the user equipment UE determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one AM RLC entity, if the PDCP entity corresponding to the multi-mode DRB or the multi-mode radio bearer was not suspended or had its transmission paused at the time of PDCP reconstruction or before PDCP reconstruction, then for each PDCP service data unit (PDCP SDU) that has been associated with a PDCP sequence number, if the user equipment UE determines that the PDCP protocol data unit (PDCP PDU) corresponding to the PDCP SDU has not yet been successfully confirmed by the lower-layer AM RLC entity, then the user equipment UE performs transmission or retransmission on the PDCP SDU.

[0017] In the method performed by the user equipment (UE) described above, it is preferred that the user equipment (UE) performs one or more of the following operations during transmission:

[0018] - Perform header compression on the PDCP SDU;

[0019] - Perform uplink data compression on the PDCP SDU;

[0020] - The PDCP SDU is then handed over to the integrity protection and encryption module for processing;

[0021] - Submit the processed PDCP PDU to the corresponding RLC entity.

[0022] In the above-described method executed by the user equipment (UE), preferably, the method further includes: receiving a request from the upper layer to restore PDCP data; and, if the user equipment (UE) determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one AM RLC entity, the transmitting PDCP entity retransmits PDCP service data units (PDCP PDUs) that have been delivered to an AM RLC entity that has been rebuilt or released before receiving the request and have not yet been confirmed by the lower layer as successfully transmitted.

[0023] According to another aspect of the present invention, a user equipment (UE) is provided, comprising: a processor; and a memory storing instructions; wherein the instructions, when executed by the processor, perform a method performed by the UE according to any one of claims 1 to 7.

[0024] Invention Effects

[0025] According to the present invention, PDCP entities that are associated with RLC entities of different modes can be reconstructed and data recovered. Attached Figure Description

[0026] The above and other features of this disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0027] Figure 1 This is a schematic diagram illustrating the association between PDCP entities and RLC entities.

[0028] Figure 2 This is a flowchart illustrating a method performed by a user equipment (UE) according to an embodiment of the present invention.

[0029] Figure 3 This is a simplified structural block diagram of the user equipment (UE) involved in the present invention. Detailed Implementation

[0030] The present disclosure will now be described in detail with reference to the accompanying drawings and specific embodiments. It should be noted that the present disclosure should not be limited to the specific embodiments described below. Furthermore, for the sake of simplicity, detailed descriptions of well-known technologies not directly related to the present disclosure have been omitted to prevent confusion in understanding the present disclosure.

[0031] The following describes some of the terms used in this disclosure. For the specific meanings of these terms, please refer to the latest relevant 3GPP documents, such as TS38.300, TS38.321, TS38.323, and TS38.331. Furthermore, the embodiments of this disclosure are not limited to broadcast / multicast services and can also be applied to other application scenarios.

[0032] UE: User Equipment.

[0033] RRC: Radio Resource Control (layer).

[0034] RRC_CONNECTED: RRC connection state.

[0035] RRC_INACTIVE: RRC inactive state.

[0036] RRC_IDLE: RRC idle state.

[0037] RAN: Radio Access Network.

[0038] NR; New RAT, New Wireless Access Technology.

[0039] PDCP: Packet Data Convergence Protocol (layer).

[0040] RLC: Radio Link Control (layer).

[0041] SDAP: Service Data Adaptation Protocol (Layer)

[0042] ROHC: Robust Header Compression

[0043] EHC: Ethernet Header Compression

[0044] UDC: Uplink Data Compression

[0045] SN: Sequence Number

[0046] As an example, an RLC can be an Acknowledged Mode (AM) RLC, an Unacknowledged Mode (UM) RLC, or a Transparent Mode (TM) RLC.

[0047] The UM RLC entity is configured to transmit or receive UM RLC entities and submit or receive RLC data PDUs.

[0048] An AM RLC entity comprises a transmitter and a receiver, and submits or receives RLC data PDUs and RLC control PDUs. In AM mode, the RLC entity submits or receives RLC data PDUs and RLC control PDUs (i.e., status PDUs). The AM RLC entity receiver uses the status PDUs to notify the peer RLC entity (i.e., the transmitter of another AM RLC entity) about successfully received RLC data PDUs and RLC data PDUs detected as lost.

[0049] SDU: Service Data Unit. A data packet received or delivered from an upper layer to a higher layer is called an SDU.

[0050] PDU: Protocol Data Unit. A PDU is a data packet received or delivered by one layer to another. For example, a PDCP data PDU is a PDCP SDU with a PDCP header added.

[0051] RB: Radio Bearer.

[0052] DRB: Data Radio Bearer.

[0053] In this disclosure, the network, base station, and RAN are interchangeable. The network may be a Long Term Evolution (LTE) network, an NR network, an enhanced Long Term Evolution (eLTE) network, or other networks defined in subsequent 3GPP versions.

[0054] PDCP entity

[0055] A PDCP entity resides at the PDCP layer. A PDCP entity can be associated with a radio bearer (RB) for transmitting data from that bearer. Such a PDCP can be referred to as the PDCP corresponding to a radio bearer, or it can be considered as the PDCP belonging to a radio bearer.

[0056] RLC entities reside in the RLC layer, and the functionality of the RLC layer is implemented by RLC entities. RLC entities can be configured in one of the following three modes:

[0057] Transparent Mode™

[0058] Unacknowledged Mode (UM)

[0059] Acknowledged Mode (AM)

[0060] An RLC entity configured in UM mode can be called a UM RLC, and an RLC entity configured in AM mode can be called an AM RLC.

[0061] A PDCP entity must be associated with at least one RLC entity. A PDCP can be associated with one UM RLC (e.g., ...). Figure 1 (a) can also be associated with multiple UM RLCs (such as Figure 1 (b) corresponds to Figure 1DRBs with structures like (a) and (b) can be called UM DRBs.

[0062] A PDCP can also be associated with an AM RLC (e.g. Figure 1 (c) can also be associated with multiple AM ​​RLCs (such as Figure 1 (d)), corresponding to Figure 1 DRBs with structures like (c) and (d) can be called AM DRBs.

[0063] A radio bearer corresponding to a PDCP or its associated PDCP can also be associated with at least one AM RLC and at least one UM RLC (e.g., Figure 1 (e)), corresponding to Figure 1 A radio bearer with a structure like (e) can be called a multi-mode radio bearer (RB). Alternatively, a radio bearer associated with at least one AM RLC and at least one UM RLC can be defined as a multi-mode radio bearer. Furthermore, it can be said that the RLC associated with this radio bearer, or the RLC associated with the PDCP of this radio bearer, has the same meaning. Such a multi-mode bearer can be used to transmit data and therefore can also be called a multi-mode data radio bearer (multi-mode DRB). Here, "multi-mode" means that the RLC entity can be in multiple modes.

[0064] Furthermore, based on the content or service type carried by the radio bearer, a radio bearer can be defined to carry multi-mode services; this can be called a multi-modality radio bearer. Here, "multi-mode" refers to the service type having multiple modes. A multi-modality radio bearer corresponds to one PDCP entity and can be associated with one or more RLC entities. These RLC entities can have the same or different modes. Therefore, such a multi-modality radio bearer can be the aforementioned UM DRB, AM DRB, or the aforementioned multi-mode DRB. Thus, a multi-modality radio bearer associated with at least one AM RLC entity can be a multi-mode DRB or an AM RRB, while a multi-modality radio bearer associated with at least one UM RLC entity can be a multi-mode DRB or a UM DRB.

[0065] PDCP entities can be divided into transmitting PDCP entities and receiving PDCP entities, which can be located at the UE and base station sides, base station and UE sides, or UE and UE sides, respectively. When PDCP receives a PDCP SDU from an upper layer, such as the RRC layer or NAS layer, it can perform the following operations:

[0066] - Start a timer discardTimerForLowImportance or a timer discardTimer associated with this PDCP SDU. When the timer discardTimerForLowImportance or the timer discardTimer times out, the UE can discard this PDCP SDU, as well as another associated PDCP SDU.

[0067] -Associate the current value of the state variable TX NEXT as the value of COUNT with this PDCP SDU;

[0068] - Update the value of TX NEXT by incrementing its current value by 1 to obtain the new value of TX NEXT.

[0069] A PDCP PDU can be a PDCP data PDU containing data, or a PDCP control PDU containing control information.

[0070] The control PDU may include:

[0071] - PDCP status report;

[0072] - Distributed ROHC feedback;

[0073] -EHC feedback;

[0074] -UDC feedback.

[0075] In multi-mode DRB or multi-mode radio bearer, when an upper-layer PDCP SDU arrives, the PDCP entity can determine the RLC entity associated with the PDCP SDU from its multiple associated RLC entities, and then deliver the corresponding PDCP PDU to that RLC entity for transmission. This determination can be achieved through configuration information or based on indication information provided by the upper-layer SDAP; there are no restrictions here. Generally, a PDCP SDU is associated with only one RLC entity, which can be a UM RLC or an AMRLC. Specifically, this association means that after integrity inclusion, encryption, and possible other processing, the resulting PDCPPDU from the PDCP SDU will be delivered to this determined RLC entity for transmission. This operation can be called routing, and it is handled by the PDCP entity.

[0076] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0077] Example

[0078] Figure 2 This is a flowchart illustrating a method performed by a user equipment (UE) according to an embodiment of the present invention. Figure 2 As shown, the method includes steps S101 and S102.

[0079] In step S101, the PDCP entity receives a request from the upper-layer Reconstruct Packet Data Convergence Protocol (PDCP). In step S102, if the PDCP entity receiving the request is a transmitting PDCP entity, the user equipment (UE) determines whether the radio bearer (RB) to which the PDCP entity belongs is a multimode data radio bearer (DRB), a multimode radio bearer associated with at least one unacknowledged radio link control (UM) RLC entity, or a multimode radio bearer associated with at least one acknowledged radio link control (AM) RLC entity.

[0080] The following section explains the operations performed by a PDCP entity, depending on whether it is a transmitting or receiving PDCP entity.

[0081] When a PDCP entity that receives a request for PDCP entity re-establishment from an upper layer (above the PDCP layer, such as the RRC layer) is a transmitting PDCP entity, the transmitting PDCP entity can perform the following operations:

[0082] Preferably, the UE can first determine whether the RB to which the PDCP entity belongs is a multi-mode DRB, and if it is determined that the RB to which it belongs is a multi-mode DRB, perform the following operations:

[0083] Alternatively, the UE can first determine whether the RB to which the PDCP entity belongs is a multi-model radio bearer associated with at least one UMRLC entity, and if it is determined that the RB to which it belongs is a multi-model radio bearer associated with at least one UM RLC entity, perform the following operations:

[0084] Alternatively, the UE can first determine whether the RB to which the PDCP entity belongs is a multi-model radio bearer associated with at least one AM RLC entity, and if it is determined that the RB to which it belongs is a multi-model radio bearer associated with at least one AM RLC entity, perform the following operations:

[0085] For multi-mode DRBs (or multi-mode radio bearers associated with at least one UM RLC entity), for each PDCP SDU already associated with a PDCP SN, if the UE determines that the corresponding PDCPPDU has not yet been delivered to the lower layer, where the lower layer refers to the RLC layer, preferably an RLC entity configured in UM mode, i.e., the PDCPSDU or its corresponding PDCPPDU is associated with a UMRLC entity, then the UE can consider that this or these PDCP SDUs were received from the upper layer of PDCP and can transmit this or these PDCP SDUs.

[0086] For a multi-mode DRB (or a multi-mode radio bearer associated with at least one AM RLC entity), if the PDCP entity corresponding to the multi-mode DRB (or the multi-mode radio bearer) has been suspended or had its transmission paused at the time of PDCP reconstruction or before PDCP reconstruction, then for each PDCP SDU that has been associated with a PDCP SN, if the UE determines that the PDCP PDU corresponding to the PDCPSDU has not yet been successfully delivered by the lower layer, where the lower layer refers to the RLC layer, preferably the RLC entity configured in AM mode in the lower layer, since successful delivery confirmation is always performed by the AM RLC entity, it is implied that the PDCP SDU or its corresponding PDCP PDU is associated with an AM RLC entity. Only these PDCP SDUs or PDUs associated with AM RLC entities need to wait for confirmation. For PDCP SDUs or PDCP PDUs associated with UM RLC entities, there is no need for the aforementioned confirmation of reception. Therefore, PDCP SDUs associated with UM RLC entities are not the PDCP SDUs that need to be considered above. In this case, the UE can assume that this or these PDCP SDUs are received from the upper layer of PDCP, and can transmit this or these PDCPSDUs.

[0087] For a multi-model radio bearer associated with at least one UM RLC entity, it can also be associated with at least one AM RLC entity. Then, the UE can perform an operation on the multi-model radio bearer associated with at least one AM RLC entity after performing an operation on the multi-model radio bearer associated with at least one UM RLC entity or at the same time.

[0088] For a multi-model radio bearer associated with at least one AM RLC entity, it can also be associated with at least one UMRLC entity. Then the UE can perform the operation for the multi-model radio bearer associated with at least one UM RLC entity after performing the operation for the multi-model radio bearer associated with at least one AM RLC entity or at the same time.

[0089] In the above operation, "the UE may consider that this or these PDCP SDUs are received from the upper layer of PDCP, and transmit this or these PDCP SDUs" can mean that the UE performs one or more of the following operations for each PDCP SDU during transmission:

[0090] - Start a timer discardTimerForLowImportance or a timer discardTimer for this PDCP SDU.

[0091] - Associate a COUNT value with this PDCP SDU

[0092] Perform header compression on this PDCP SDU.

[0093] Perform uplink data compression on this PDCP SDU.

[0094] - The TX NEXT value is used to perform integrity protection and ciphering on this PDCP SDU.

[0095] - Set the PDCP SN value of the PDCP PDU corresponding to this PDCP SDU. This value can be obtained based on TX NEXT.

[0096] - Update the TX NEXT value by incrementing it by 1 (increment TX NEXT by one).

[0097] - The processed PDCP PDU is handed over to the lower layer, that is, to the corresponding RLC entity.

[0098] For a multi-mode DRB (or a multi-mode radio bearer associated with at least one AM RLC entity), if the PDCP entity corresponding to the multi-mode DRB (or the multi-mode radio bearer) was not suspended or had its transmission paused at the time of PDCP reconstruction or before PDCP reconstruction, then for each PDCP SDU that has been associated with a PDCP SN, if the UE determines that the PDCP PDU corresponding to the PDCP SDU has not yet been successfully delivered by the lower layer (where the lower layer refers to the RLC layer, preferably the RLC entity configured in AM mode), since successful delivery confirmation is always performed by the AM RLC entity, it is implied that the PDCP SDU or its corresponding PDCP PDU is associated with an AM RLC entity. Only these PDCP SDUs or PDUs associated with AM RLC entities need to wait for confirmation. For PDCP SDUs or PDCPPDUs associated with UMRLC entities, the aforementioned need for confirmation of reception does not exist. Therefore, PDCPSDUs associated with UMRLC entities are not the PDCP SDUs that need to be considered. The UE can perform transmission or retransmission of the PDCP SDU. This can be done during transmission by one or more of the following operations:

[0099] Perform header compression on this PDCP SDU.

[0100] -Perform uplink data compression on this PDCP SDU. Preferably, if uplink data compression has already been performed on this PDCP SDU before PDCP reconstruction, then the compressed PDCP SDU can be submitted to the integrity protection and encryption function module for processing.

[0101] - Submit this PDCP SDU to the integrity protection and ciphering function module for processing.

[0102] - The processed PDCP PDU is handed over to the lower layer, that is, to the corresponding RLC entity.

[0103] When an entity receives a request for PDCP data recovery from an upper layer (above the PDCP layer, such as the RRC layer) for a multi-mode DRB (or for a multi-mode radio bearer associated with at least one AMRLC entity), and the transmitting PDCP entity is the transmitting PDCP entity, the transmitting PDCP entity can also perform the following operations:

[0104] Preferably, the UE can first determine whether the RB to which the PDCP entity belongs is a multi-mode DRB, and if it is determined that the RB to which it belongs is a multi-mode DRB, perform the following operations:

[0105] Alternatively, the UE can first determine whether the RB to which the PDCP entity belongs is a multi-model radio bearer associated with at least one AM RLC entity, and if it is determined that the RB to which it belongs is a multi-model radio bearer associated with at least one AM RLC entity, perform the following operations:

[0106] Retransmission of PDC / PPDUs is performed. Here, PDCP / PDCU refers to those previously submitted to the AM RLC entity. "Previously" preferably means before receiving the aforementioned request to recover PDCP data. The RLC entity submitted here refers to an AM RLC entity that has been rebuilt or released, and these PDCP PDUs are those whose successful delivery has not yet been confirmed by lower layers. When retransmitting these PDCP PDUs, they can be retransmitted in a certain order. This order can be determined based on the COUNT value associated with each PDCP PDU, for example, retransmitting in ascending order of COUNT values.

[0107] As a supplement, upon receiving a request to recover PDCP data for a multi-mode DRB, the aforementioned retransmission operation is not required for the PDCP PDUs delivered to the UM RLC entity in the multi-mode DRB or the multi-mode radio bearer.

[0108] When a PDCP entity that receives a request for PDCP entity re-establishment from an upper layer (above the PDCP layer, such as the RRC layer) is an accepting PDCP entity, the accepting PDCP entity can also perform the following operations:

[0109] - For multi-mode DRBs (or multi-mode radio bearers associated with at least one AM RLC entity), set RX_NEXT and RX_DELIV to their initial values.

[0110] - For multi-mode DRBs (or multi-mode radio bearers associated with at least one AM RLC entity), reset the ROHC protocol for the downlink.

[0111] ROHC protocol for downlink

[0112] - For multi-mode DRBs (or multi-mode radio bearers associated with at least one AM RLC entity), ROHC execution header decompression is performed on all stored PDCP SDUs.

[0113] (perform header decompression using ROHC for all stored PDCP

[0114] SDUs).

[0115] PDCP entities can be configured to use uplink data compression. For a DRB, the UE can perform uplink data compression on received PDCP SDUs from the upper layer. However, for multi-mode DRBs (or multi-mode radio bearers associated with at least one AMRLC entity), the UE does not need to perform uplink data compression on all PDCP SDUs from the upper layer, but only on PDCP SDUs sent to a specified RLC entity. For example, the PDCP configuration information received by the UE can indicate the identification information of the RLC entity that needs uplink data compression, such as the logical channel number. If more than one associated RLC entity needs uplink data compression and uses different compression dictionaries, the UE's transmitting PDCP entity can enable the receiving PDCP entity to distinguish UDC feedback control PDUs in the following way.

[0116] Method 1: For a transmitting PDCP entity associated with a multi-mode DRB (or a multi-mode radio bearer associated with at least one AM RLC entity),

[0117] If the UE determines that a PDCP PDU is a PDCP DATAPDU, it submits the PDCP DATAPDU to the corresponding or associated RLC entity.

[0118] If the UE determines that a PDCP PDU is not a PDCP DATA PDU, that is, if the UE determines that a PDCP PDU is a PDCP Control PDU,

[0119] If the PDCP Control PDU is a PDCP Control PDU for UDC feedback

[0120] Then it can be submitted to the corresponding or associated RLC entity, which can be the aforementioned RLC entity that is instructed to perform uplink data compression processing.

[0121] If the PDCP Control PDU is not a PDCP Control PDU for UDC feedback (e.g., it's a PDCP Control PDU for interspersed ROHC feedback), or it's a PDCP status report, then it can be submitted to a default RLC entity. Such a default RLC entity can be indicated in the configuration information. For example, the default RLC entity can be set to a logical channel number, and the RLC entity identified by that logical channel number will be the default RLC entity. A default RLC entity can also be implicitly indicated. For example, the RLC entity managed by the logical channel number with the smallest or largest value can always be used as the default RLC entity. Another example is comparing the channel priority values ​​of all RLC entities associated with a PDCP, and always using the RLC entity with the smallest or largest channel priority value as the default RLC entity.

[0122] Another implementation of the above solution could be

[0123] For a transmit PDCP entity associated with a multi-mode DRB (or a multi-mode radio bearer associated with at least one AM RLC entity),

[0124] If the UE determines that a PDCP PDU is a PDCP DATAPDU, it submits the PDCP DATAPDU to the corresponding or associated RLC entity.

[0125] If the UE determines that a PDCP PDU is not a PDCP DATA PDU, that is, if the UE determines that a PDCP PDU is a PDCP Control PDU,

[0126] If the PDCP Control PDU is a PDCP status report, it can be submitted to a default RLC entity. Such a default RLC entity can be indicated in the configuration information, or the default RLC entity can be set to a certain logical channel number, then the RLC entity identified by that logical channel number is the default RLC entity.

[0127] If the PDCP Control PDU is not a PDCP status report, for example, if the PDCP Control PDU could be a PDCP Control PDU for UDC feedback, then it can be submitted to the corresponding or associated RLC entity. The corresponding or associated RLC entity can be the aforementioned RLC entity that is instructed to perform uplink data compression processing.

[0128] Method 2:

[0129] The PDCP Control PDU generated by the UE can contain identification information of RLC entities, such as logical channel numbers, or identification information that indicates the RLC entity. For example, for a PDCP associated with two RLC entities, sequence number 1 corresponds to the first RLC entity associated with this PDCP entity, and sequence number 2 corresponds to the second RLC entity associated with this PDCP entity. The RLC entities can be sorted in ascending order according to the magnitude of their logical signals, with the RLC entity with the smaller logical channel number value being the first RLC entity and the RLC entity with the larger logical channel number value being the second RLC entity. By including identification information in the PDCP Control PDU, the receiving PDCP entity can distinguish which RLC entity the control PDU is used to control and manage. Taking the UDC feedback PDCP control PDU as an example, a PDCP control PDU can be designed that includes feedback information and RLC entity identification information.

[0130] When the UE determines that a PDCP PDU is a PDCP Control PDU.

[0131] If the PDCP Control PDU contains the identification information of the RLC entity,

[0132] Then it can be submitted to the corresponding or associated RLC entity, that is, the RLC entity indicated by the identification information or the corresponding entity;

[0133] If the PDCP Control PDU does not contain the identification information of the RLC entity,

[0134] Then it can be submitted to a default RLC entity.

[0135] It can also be

[0136] When the UE determines that a PDCP PDU is a PDCP Control PDU.

[0137] If the PDCPControlPDU contains the identification information of an RLC entity, it can be submitted to a default RLC entity.

[0138] Furthermore, the meaning of the parameters involved in the embodiments of this disclosure is briefly described below. For details, please refer to the latest 3GPP technical specifications. t-Reordering is used to detect the loss of PDCP data PDUs. The COUNT value is composed of a superframe number (HFN) and the PDCP sequence number (SN). TX_NEXT is a state variable indicating the COUNT value of the next transmitted PDCP SDU; the initial value of TX_NEXT is zero. RX_NEXT is a state variable indicating the COUNT value of the next expected received PDCP SDU. RX_DELIV is a state variable indicating the COUNT value of the first PDCP SDU that has not yet been delivered to the upper layer but is still waiting to be received. HFN is the superframe number. The initial values ​​(COUNT) of RX_NEXT and RX_DELIV are determined by HFN Initial. The PDCP SN is determined by the sequence number x of the first received PDCP PDU or SDU, for example, the PDCP SN is (x-0.5×2[pdcp-SN-SizeDL-1])modulo(2[pdcp-SN-SizeDL]). pdcp-SN-SizeDL is the downlink PDCP sequence number size.

[0139] Figure 3 This is a simplified structural block diagram of the user equipment (UE) involved in this invention. Figure 3As shown, the user equipment UE300 includes a processor 301 and a memory 302. The processor 301 may include, for example, a microprocessor, a microcontroller, an embedded processor, etc. The memory 302 may include, for example, volatile memory (such as random access memory, RAM), a hard disk drive (HDD), non-volatile memory (such as flash memory), or other memory. Program instructions are stored on the memory 302. When executed by the processor 301, these instructions can perform the methods described in detail herein, executed by the user equipment.

[0140] Additionally, the computer-executable instructions or program running on the device according to this disclosure may be a program that enables the computer to perform the functions of the embodiments of this disclosure by controlling the central processing unit (CPU). The program or the information processed by the program may be temporarily stored in volatile memory (such as random access memory, RAM), hard disk drive (HDD), non-volatile memory (such as flash memory), or other memory systems.

[0141] Computer-executable instructions or programs for implementing the functions of the embodiments of this disclosure can be recorded on a computer-readable storage medium. The corresponding functions can be implemented by causing a computer system to read and execute the programs recorded on the recording medium. The term "computer system" herein can refer to a computer system embedded in the device, and may include an operating system or hardware (such as peripheral devices). "Computer-readable storage medium" can be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a short-time dynamic program storage medium, or any other computer-readable recording medium.

[0142] Various features or functional modules of the devices used in the above embodiments can be implemented or executed by circuits (e.g., monolithic or multi-chip integrated circuits). Circuits designed to perform the functions described in this specification may include general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination of the above devices. A general-purpose processor may be a microprocessor, or any existing processor, controller, microcontroller, or state machine. The circuits described above may be digital circuits or analog circuits. In cases where advancements in semiconductor technology have led to new integrated circuit technologies that replace existing integrated circuits, one or more embodiments of this disclosure may also be implemented using these new integrated circuit technologies.

[0143] Furthermore, this disclosure is not limited to the embodiments described above. Although various examples of the embodiments have been described, this disclosure is not limited thereto. Fixed or non-mobile electronic devices installed indoors or outdoors can be used as terminal devices or communication devices, such as AV equipment, kitchen equipment, cleaning equipment, air conditioners, office equipment, vending machines, and other household appliances.

[0144] As described above, embodiments of this disclosure have been described in detail with reference to the accompanying drawings. However, the specific structure is not limited to the above embodiments, and this disclosure also includes any design modifications that do not depart from the spirit of this disclosure. Furthermore, various modifications can be made to this disclosure within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included within the technical scope of this disclosure. In addition, components with the same effects described in the above embodiments can be substituted for each other.

Claims

1. A method executed by a user equipment (UE), comprising: The PDCP entity receives requests from the upper-layer Reconstruction Packet Data Convergence Protocol (PDCP); and If the PDCP entity receiving the request is a transmitting PDCP entity, the user equipment (UE) determines whether the radio bearer (RB) to which the PDCP entity belongs is a multimode data radio bearer (DRB), a multimode radio bearer associated with at least one unacknowledged radio link control (UMRLC) entity, or a multimode radio bearer associated with at least one acknowledged radio link control (AMRLC) entity. The multimodal DRB is a DRB that associates at least one UM RLC entity and at least one AM RLC entity.

2. The method executed by the user equipment (UE) according to claim 1, wherein, When the user equipment (UE) determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one UM RLC entity, For each PDCP Service Data Unit (PDCPSDU) that has been associated with a PDCP sequence number, if the User Equipment (UE) determines that the PDCP Protocol Data Unit (PDCPPDU) corresponding to the PDCP SDU has not yet been delivered to the lower-layer UMRLC entity, then the UE considers the PDCP SDU to have been received from the upper layer of PDCP and transmits the PDCP SDU.

3. The method executed by the user equipment (UE) according to claim 1, wherein, When the user equipment (UE) determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one AM RLC entity. If the PDCP entity corresponding to the multi-mode DRB or the multi-mode radio bearer has been suspended or paused during or before the PDCP reconstruction, then for each PDCP Service Data Unit (PDCP SDU) associated with a PDCP sequence number, if the UE determines that the PDCP Protocol Data Unit (PDCP PDU) corresponding to the PDCP SDU has not yet been successfully confirmed by the lower-layer AM RLC entity, then the UE considers the PDCP SDU to have been received from the upper layer of PDCP and transmits the PDCP SDU.

4. The method performed by the user equipment (UE) according to claim 2 or 3, wherein, The user equipment (UE) performs one or more of the following operations on each PDCPSDU during transmission: - Start a timer for the PDCP SDU; - Associate a count value COUNT with the PDCP SDU; - Perform header compression on the PDCP SDU; - Perform uplink data compression on the PDCP SDU; - The PDCP SDU is protected for integrity and encrypted using the value of the state variable TX NEXT; - Set the value of the PDCP sequence number of the PDCPPDU corresponding to the PDCP SDU. This value can be obtained based on the state variable TXNEXT. - Update the value of the state variable TX NEXT by incrementing its value by 1; - Submit the processed PDCP PDU to the corresponding RLC entity.

5. The method performed by the user equipment (UE) according to claim 1, wherein, When the user equipment (UE) determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one AM RLC entity. If the PDCP entity corresponding to the multi-mode DRB or the multi-mode radio bearer is not suspended or interrupted during or before the PDCP reconstruction, then for each PDCP service data unit (PDCP SDU) associated with a PDCP sequence number, if the user equipment (UE) determines that the PDCP protocol data unit (PDCP PDU) corresponding to the PDCP SDU has not yet been successfully confirmed by the lower-layer AM RLC entity, then the UE performs transmission or retransmission of the PDCP SDU.

6. The method performed by the user equipment (UE) according to claim 5, wherein, The user equipment (UE) performs one or more of the following operations during transmission: - Perform header compression on the PDCP SDU; - Perform uplink data compression on the PDCP SDU; - The PDCP SDU is then handed over to the integrity protection and encryption module for processing; - Submit the processed PDCP PDU to the corresponding RLC entity.

7. The method performed by the user equipment (UE) according to claim 1, wherein, The method executed by the device UE further includes: Receive requests from the upper layer to restore PDCP data; and When the user equipment (UE) determines that the RB to which the PDCP entity belongs is a multi-mode DRB or a multi-mode radio bearer associated with at least one AM RLC entity, the transmitting PDCP entity retransmits PDCP service data units (PDCP PDUs) that have been delivered to an AM RLC entity that has been rebuilt or released before the request was received, and which have not yet been confirmed by the lower layer as successfully transmitted.

8. A user equipment (UE), comprising: processor; as well as A memory storing instructions; wherein the instructions, when executed by the processor, perform a method performed by the user equipment (UE) according to any one of claims 1 to 7.

Images