Dynamic Packet Aggregation Protocol Configuration

Abstract

The present disclosure relates generally to wireless communications, and more particularly to systems and methods for dynamic configuration of a packet convergence protocol (PDCP) configuration. In one embodiment, the method performed by a communication device includes: receiving configuration information from a communication node; and for a packet convergence protocol of each data radio bearer, determining a number of replicas or logical paths based on the configuration information.

Description

Technical Field

[0001] The present disclosure relates generally to wireless communications and, more particularly, to systems and methods for dynamic configuration of Data Packet Convergence Protocol (PDCP) configurations. Background Art

[0002] As the number of digital data applications and services continues to proliferate, the demands and challenges on network resources and operators will continue to increase. Being able to deliver the full range of network performance features required for future services is one of the major technical challenges facing service providers today. Summary of the invention

[0003] The exemplary embodiments disclosed herein are directed to solving problems related to one or more of the problems presented in the prior art, as well as providing additional features that will become apparent when referring to the following detailed description in conjunction with the accompanying drawings. According to various embodiments, exemplary systems, methods, devices, and computer program products are disclosed herein. However, it should be understood that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who have read this disclosure that various modifications may be made to the disclosed embodiments while remaining within the scope of the invention.

[0004] In one embodiment, a method performed by a communication device includes: receiving configuration information from a communication node; and determining, for a packet aggregation protocol per data radio bearer, a number of replicas or a logical path based on the configuration information.

[0005] In another embodiment, a method performed by a communication node includes sending configuration information to a communication device, wherein the communication device includes a centralized unit and a distributed unit, wherein the communication device is configured to determine, for a packet aggregation protocol for each data radio bearer, a number of replicas or a logical path based on the configuration information.

[0006] In another embodiment, a communication device includes a receiver configured to receive configuration information from a communication node and a processor configured to determine, for a packet aggregation protocol per data radio bearer, a number of replicas or a logical path based on the configuration information.

[0007] In another embodiment, a communication node includes: a centralized unit; a distributed unit; and a transmitter, the transmitter being configured to: send configuration information to a communication device, wherein the communication device is configured to determine, for a packet aggregation protocol for each data radio bearer, a number of replicas or a logical path based on the configuration information. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Various exemplary embodiments of the present invention are described in detail below with reference to the accompanying drawings. The accompanying drawings are provided for illustrative purposes only and only depict exemplary embodiments of the present invention to facilitate the reader's understanding of the present invention. Therefore, the accompanying drawings should not be considered as limiting the breadth, scope or applicability of the present invention. It should be noted that for clarity and ease of description, these drawings are not necessarily drawn to scale.

[0009] Figure 1 An exemplary wireless communication network is shown in which the techniques disclosed herein may be implemented in accordance with some embodiments.

[0010] Figure 2 A block diagram of an exemplary wireless communication system for transmitting and receiving wireless communication signals according to some embodiments of the present invention is shown.

[0011] Figure 3 is a block diagram of Data Packet Convergence Protocol (PDCP) replication with more than two replicas according to some embodiments.

[0012] Figure 4 is a flow chart illustrating a process of user equipment (UE) behavior when a current uplink (UL) transmission does not match the reliability requirement according to some embodiments.

[0013] Figure 5A is a sequence diagram illustrating a process in which the number of replicas (eg, for PDCP duplication) is configured through radio resource control (RRC) signaling in a network-based solution according to some embodiments.

[0014] Figure 5B is a sequence diagram illustrating a process in which the number of replicas (eg, for PDCP duplication) is configured by a medium access control (MAC) control element (CE) in a network-based solution according to some embodiments.

[0015] Figure 5C is a sequence diagram illustrating a process in which the number of replicas (eg, for PDCP duplication) is configured in a UE-based solution according to some embodiments.

[0016] Figure 5D is a sequence diagram illustrating a process in which the number of replicas (eg, for PDCP duplication) is configured in a UE and BS based solution according to some embodiments.

[0017] Fig. 6Ais a sequence diagram illustrating a process of determining a logical path with a set number of replicas (eg, for PDCP duplication) for radio link control (RLC) entity determination in a UE-based solution according to some embodiments.

[0018] Figure 6B is a sequence diagram illustrating a process of determining a logical path with a set number of copies (eg, for PDCP duplication) for RLC entity determination in a network (NW) based solution according to some embodiments.

[0019] Figure 6C is a sequence diagram illustrating a process of determining a logical path with a set number of replicas (eg, for PDCP duplication) for cell (eg, serving cell) determination in a UE-based solution according to some embodiments.

[0020] Fig.6D is a sequence diagram illustrating a process of determining a logical path with a set number of replicas (eg, for PDCP duplication) for serving cell determination in a NW-based solution according to some embodiments.

[0021] Fig. 7A is a sequence diagram illustrating a process of UE behavior when the current UL transmission does not match the reliability requirement according to some embodiments.

[0022] Figure 7B is a sequence diagram illustrating the process of UE and BS behaviors when the current UL transmission does not match the reliability requirement according to some embodiments. DETAILED DESCRIPTION

[0023] Various exemplary embodiments of the present invention are described below with reference to the accompanying drawings to enable those of ordinary skill in the art to make and use the present invention. As will be apparent to those of ordinary skill in the art, after reading this disclosure, various changes or modifications may be made to the examples described herein without departing from the scope of the present invention. Therefore, the present invention is not limited to the exemplary embodiments and applications described and illustrated herein. In addition, the specific order or hierarchy of steps in the methods disclosed herein are merely exemplary methods. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes may be rearranged while remaining within the scope of the present invention. Therefore, it should be understood by those of ordinary skill in the art that the methods and techniques disclosed herein present various steps or actions in a sample order, and that the present invention is not limited to the specific order or hierarchy presented, unless otherwise expressly stated.

[0024] The following discussion may involve functional entities or processes similar to those mentioned above with respect to conventional communication systems. However, as will be appreciated by those of ordinary skill in the art, such conventional functional entities or processes do not perform the functions described below, and therefore, will need to be modified or specifically configured to perform one or more of the operations described below. Furthermore, those of ordinary skill in the art, after reading this disclosure, should be able to configure the functional entities to perform the operations described herein.

[0025] Figure 1 An exemplary wireless communication network 100 is shown in which the techniques disclosed herein may be implemented according to an embodiment of the present disclosure. Such exemplary network 100 includes a base station 102 (hereinafter referred to as "BS 102") and a plurality of user equipment terminals 104 (hereinafter referred to as "UE 104") that may communicate with each other via respective communication links 110 (e.g., wireless communication channels), and a cluster of conceptual cells 126, 130, 132, 134, 136, 138, and 140 covering a geographic area with the network 101. Each UE 104 may undergo a random access procedure to join the network 101. In Figure 1 1, BS 102 and each UE 104 are contained within the respective geographic boundaries of cell 126. Each of the other cells 130, 132, 134, 136, 138, and 140 may include at least one base station operating under its allocated bandwidth to provide adequate radio coverage to its intended users. Thus, reference to a cell may be a brief reference to a BS having an associated coverage area or region (e.g., a cell). In some embodiments, a cell may be interchangeably referred to as a BS or a node.

[0026] For example, BS102 can operate under the allocated channel transmission bandwidth (e.g., spectrum) to provide sufficient coverage to each UE 104. The spectrum can be adjusted to define an authorized range and / or an unauthorized range. BS102 and each UE 104 can communicate via a downlink radio frame 118 and an uplink radio frame 124, respectively. Radio frames can also be more simply referred to as frames. Each frame 118 / 124 can be further divided into subframes 120 / 127, which can include data symbols 122 / 128. In the present disclosure, BS102 and each UE 104 are described herein as non-limiting examples of "communication nodes" that can generally practice the methods disclosed herein. According to various embodiments of the present invention, such communication nodes are capable of wireless and / or wired communication. In some embodiments, a communication device can more specifically refer to a UE associated with a BS, and a communication node can more specifically refer to a BS associated with a UE.

[0027] Figure 2A block diagram of an exemplary wireless communication system 200 for transmitting and receiving wireless communication signals (e.g., OFDM / OFDMA signals) according to some embodiments of the present invention is shown. System 200 may include components and elements configured to support known or conventional operating features that need not be described in detail herein. In an exemplary embodiment, as described above, system 200 may be used in applications such as Figure 1 Data symbols are transmitted and received in a wireless communication environment such as the wireless communication environment of the network 100 or the wireless communication environment of the network 100.

[0028] The system 200 generally includes a base station 202 (hereinafter referred to as a “station environment”) and a user equipment terminal 204 (hereinafter referred to as a “station environment”). The BS 202 includes a BS (base station) transceiver module 210, a BS antenna 212, a BS processor module 214, a BS memory module 216, and a network communication module 218, each of which is coupled and interconnected to each other via a data communication bus 220 as needed. The UE 204 includes a UE (user equipment) transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each of which is coupled and interconnected to each other via a data communication bus 240 as needed. The BS 202 communicates with the UE 204 via a communication channel 250, which may be any wireless channel or other medium known in the art suitable for the transmission of the data described herein.

[0029] As will be appreciated by those skilled in the art, the system 200 may also include Figure 2 Any number of modules other than the modules shown in . It will be appreciated by those skilled in the art that the various illustrative blocks, modules, circuits, and processing logic described in conjunction with the embodiments disclosed herein can be implemented in hardware, computer-readable software, firmware, or any actual combination thereof. In order to clearly illustrate the interchangeability and compatibility of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps are generally described according to their functions. Whether such functions are implemented as hardware, firmware, or software depends on specific applications and design constraints imposed on the entire system. People familiar with the concepts described herein can implement such functions in a manner suitable for each specific application, but the decision of such an embodiment should not be interpreted as limiting the scope of the present invention.

[0030] According to some embodiments, the UE transceiver module 230 may be referred to herein as an "uplink" transceiver module 230, which includes RF transmitter and receiver circuitry each coupled to an antenna 232. A duplex switch (not shown) may alternatively couple the uplink transmitter or receiver to the uplink antenna in a time duplex manner. Similarly, according to some embodiments, the BS transceiver module 210 may be referred to herein as a "downlink" transceiver module 210, which includes RF transmitter and receiver circuitry each coupled to an antenna 212. The downlink duplex switch may alternatively couple the downlink transmitter or receiver to the downlink antenna 212 in a time duplex manner. The operation of the two transceiver modules 210 and 230 is coordinated in time so that the uplink receiver is coupled to the uplink antenna 232 for receiving transmissions over the wireless transmission link 250 while the downlink transmitter is coupled to the downlink antenna 212.

[0031] The UE transceiver module 230 and the BS transceiver module 210 are configured to communicate via a wireless data communication link 250 and cooperate with an appropriately configured RF antenna device 212 / 232 capable of supporting a specific wireless communication protocol and modulation scheme. In some exemplary embodiments, the UE transceiver module 230 and the BS transceiver module 210 are configured to support industry standards such as Long Term Evolution (LET) and emerging 5G standards. However, it should be understood that the present invention is not necessarily limited to specific standards and associated protocols in application. On the contrary, the UE transceiver module 230 and the BS transceiver module 210 can be configured to support alternative or additional wireless data communication protocols, including future standards or variants thereof.

[0032] According to various embodiments, BS202 may be, for example, an evolved Node B (eNB), a serving BS, a target BS, a femtocell or a microcell. In some embodiments, UE 204 may be embodied in various types of UEs, such as mobile phones, smart phones, personal digital assistants (PDAs), tablet computers, laptop computers, wearable computing devices, and the like. Processor module 214 and processor module 236 may be implemented or implemented using a general-purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, a discrete gate or transistor logic, a discrete hardware component, or any combination thereof designed to perform the functions described herein. In this way, the processor may be implemented as a microprocessor, a controller, a microcontroller, a state machine, and the like. The processor may also be implemented as a combination of computing devices, such as a combination of a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a digital signal processor core, or any other such configuration.

[0033] In addition, the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, firmware, software modules executed by the processor module 214 and the processor module 236, respectively, or in any practical combination thereof. The memory module 216 and the memory module 234 may be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage and / or computer-readable medium known in the art. In this regard, the memory module 216 and the memory module 234 may be coupled to the transceiver module 210 and the transceiver module 230, respectively, so that the transceiver module 210 and the transceiver module 230 may read information from and write information to the memory module 216 and the memory module 234, respectively. The memory module 216 and the memory module 234 may also be integrated into their respective transceiver modules 210 and 230. In some embodiments, the memory module 216 and the memory module 234 may each include a cache memory for storing temporary variables or other intermediate information during the execution of instructions to be executed by the transceiver module 210 and the transceiver module 230, respectively. The memory module 216 and the memory module 234 may also each include a non-volatile memory for storing instructions to be executed by the transceiver module 210 and the transceiver module 230, respectively.

[0034] The network communication module 218 generally represents the hardware, software, firmware, processing logic and / or other components of BS202, which enables bidirectional communication between the BS transceiver module 210 and other network components and communication nodes configured to communicate with BS202. For example, the network communication module 218 can be configured to support Internet or WiMAX services. In a typical deployment, but not limited to this, the network communication module 218 provides an 802.3 Ethernet interface so that the BS transceiver module 210 can communicate with a traditional Ethernet-based computer network. In this way, the network communication module 218 may include a physical interface for connecting to a computer network (e.g., a mobile switching center (MSC)). The terms "configured for", "configured to" and their variations, as used herein with respect to a specific operation or function, refer to a device, component, circuit, structure, machine, signal, etc. that is physically or virtually constructed, programmed, formatted and / or arranged to perform a specific operation or function.

[0035] It may be desirable to introduce replication with multiple copies for a Packet Data Convergence Protocol (PDCP) to increase robustness of uplink (UL) transmissions. Such PDCP replication with multiple copies may affect issues with UL transmission operations that may have multiple radio link control (RLC) entities associated with the PDCP. Moreover, such PDCP replication with multiple copies may affect activation and / or deactivation of the PDCP replication with multiple copies.

[0036] 5G New Radio (NR) may introduce a dual connection structure for communication. More specifically, the UE may be configured with two RLC entities for PDCP. For example, the UE may perform selection of an RLC entity. PDCP data packet data units (PDUs) may also be used by the RLC entity, and the PDCP data PDUs are generated for activation duplication or deactivation duplication. For ease of discussion, reference to duplication may refer to PDCP duplication, and reference to duplication may refer to duplication made during the PDCP duplication process.

[0037] In various embodiments, when PDCP duplication is activated, PDCP may generate two copies of the PDCP data PDU and transmit them to two associated RLC entities respectively. When PDCP duplication is deactivated, PDCP may transmit the PDCP data PDU to the RLC entity when at least one of the following two conditions is met. The first condition may be when the total amount of data waiting for initial transmission in the PDCP entity and the two associated RLC entities is greater than or equal to ul-dataSplitThreshold. The PDCP entity may then submit the generated PDCP data PDU to the primary RLC entity or the secondary RLC entity. The second condition may be when the PDCP entity submits the generated PDCP data PDU to the primary RLC entity.

[0038] In certain embodiments, activation / deactivation of PDCP duplication may be based on RRC configuration or reconfiguration. More specifically, an information element (IE) or field "pdcp-Duplication" configured in the PDCP configuration may be set or reset to a "true" or "false" value for activating or deactivating PDCP duplication.

[0039] In another embodiment, the activation / deactivation of PDCP duplication may be based on the activation or deactivation of PDCP duplication as indicated in a medium access control (MAC) control element (CE). More specifically, a data radio bearer identifier (ID) may be included in the MAC CE to indicate the activation or deactivation of PDCP duplication. The MAC entity may notify higher layers upon receiving this MAC CE.

[0040] In various embodiments, PDCP duplication may be introduced to improve the robustness of data transmission for the New Radio Internet of Things (NRIIOT). For example, PDCP duplication may be applied to Layer 2 (L2) and / or Layer 3 (L3) to improve the robustness of data transmission. Specifically, resource-efficient PDCP duplication may be coordinated between nodes for PDCP duplication activation to ensure resource efficiency, thereby avoiding unnecessary duplicate transmissions. In addition, PDCP duplication with more than 2 copies may utilize a combination of dual connectivity (DC) and / or carrier aggregation (CA), where data transmission is performed from a maximum of two nodes.

[0041] Figure 3300 is a block diagram of Packet Convergence Protocol (PDCP) replication with more than two replicas according to some embodiments. Block diagram 300 may include a UE 302 utilizing four RLC entities 304. Each two of the RLC entities 304 may utilize respective MACs 306. Each RLC entity 304 may facilitate transmission of a respective replica. Additionally, a combination of a particular RLC entity and a particular MAC and an associated serving cell / BS (not shown) may be referred to as a logical path (which may include an RLC entity and a corresponding logical channel (LCH) and a corresponding air interface). Thus, block diagram 300 may include 4 replicas (e.g., due to four RLC entities), which is greater than an implementation utilizing 2 replicas.

[0042] Therefore, PDCP replication with more than 2 copies is easier to meet the reliability requirements of data transmission than only 2 copies. However, more copies means greater waste of resources. Therefore, it may be desirable to design a technology to improve data transmission reliability while reducing resource consumption.

[0043] Systems and methods according to various embodiments disclose dynamic PDCP configuration. More specifically, dynamic PDCP configuration can address how to activate or deactivate PDCP replication with multiple copies, and how to operate UL transmission under both activated and deactivated PDCP replication. This deactivation or activation of PDCP replication can be UE-based, network (NW)-based, or a combination of both UE-based and NW-based. By being network-based, the dynamic PDCP configuration can determine the PDCP replication configuration from a cell or BS (from which the UE is connected to the NW). Moreover, by being UE-based, the dynamic PDCP configuration can determine the PDCP replication configuration from the UE in a flexible manner.

[0044] In various embodiments for UL transmissions utilizing more than two RLC entities associated with a PDCP entity, the following two steps may be referred to as baseline steps. Baseline step 1 may be when the UE receives a PDCP duplication configuration from the NW. Baseline step 2 may be activating or deactivating PDCP duplication and determining the number of copies (e.g., duplicate copies) based on measurements from the UE side and / or through control signals from the NW side (e.g., as indicated by the NW side), as well as determining the radio link control entity and / or serving cell to be used for each copy transmission. For ease of discussion, various exemplary issues will be discussed in turn below with reference to these baseline steps.

[0045] A first exemplary question may be which parameters may be used for PDCP duplication. In various embodiments, the initial state of PDCP duplication may be indicated for carrier aggregation (CA) duplication and / or dual connection (DC) duplication. The primary path used for duplication may indicate the primary path that may be used for the transmission of PDCP data PDUs while duplication is deactivated, and for the transmission of PDCP control PDUs while duplication is activated. This primary path may be configured per cell group. Moreover, the primary path may include a cell group (CG) indication (e.g., a CG identifier) ​​and / or a logical channel (LCH) identifier (ID). Thresholds for PDCP duplication may be used to activate or deactivate PDCP duplication, including CA duplication and DC duplication. Thresholds for UL transmission operations may be used for UE-based UL transmission operations. Moreover, time window configuration parameters may be used for UE monitoring of the current wireless environment.

[0046] Various embodiments may include a network (e.g., a cell or BS) with a centralized (CU) unit and a distributed unit (DU), also referred to as a CU / DU separation case. In the CU / DU separation case, the DU may inform the CU of the configured LCH ID. The CU may then allocate an LCH ID for the initial state of PDCP duplication. Similarly, the DU may inform the CU of the configured primary path for each cell group. This notification may be performed over a radio link.

[0047] The second exemplary problem to be solved is how to handle multiple PDCP replication copies during baseline step 2. In various embodiments, for situations where PDCP replication utilizes multiple copies (e.g., more than 2 copies), the following options can be utilized. As a first option, the multiple PDCP replication copies can be directly processed the same, whether they are used for CA or for DC. As a second option, CA replication and DC replication are handled separately. More specifically, they can be handled separately in the following situations: NW controls CA replication and DC replication activation / deactivation; NW controls DC replication, while CA replication is handled by the UE itself; NW controls CA replication, while DC replication is handled by the UE itself; or finally, both CA and DC replication can be handled by the UE itself. Therefore, PDCP replication control can be considered as two layers. That is, one for DC replication and the other for CA replication.

[0048] In another embodiment, in the case where the NW has a separate CU-DU (e.g., separate CU / DU), the CU may notify the DU of the configuration or reconfiguration of the PDCP duplication state for scheduling UL grants by the DU. This notification may also include the number of activated RLC entities, LCH indicators, cell group indicators, and / or PDCP duplication indicators.

[0049] A third exemplary problem to be solved may be how to determine the number of copies when PDCP duplication is activated in the context of baseline step 2. For this third exemplary problem, if duplication is activated, the number of duplicate copies (e.g., more than 2) may be dynamically determined based on the current wireless environment. The following three alternative embodiments may illustrate aspects of an exemplary solution to this third exemplary problem. The first alternative embodiment may focus on a NW-based solution. More specifically, as a standard approach, the NW may configure the number of copies based on the current wireless environment and the service reliability requirements determined by a MAC CE or a radio resource control (RRC) configuration. For example, a MAC CE may include an indication of the number of copies, or an indication of a duplicated activated LCH, or an indication of whether there is CA or DC duplication. In some embodiments, this MAC CE may be the same as or different from a MAC CE indicating PDCP duplication activation or deactivation.

[0050] Certain embodiments may utilize dual connection (DC) replication. More specifically, an inter-node configuration may be introduced that specifies the configuration between a master node (MN) and a secondary node (SN) to determine whether DC replication should be used. This determination may be communicated to the UE via, for example, RRC signaling, PDCP control PDU, or MAC CE communication. The PDCP control PDU may be sent from the MN and the SN to the UE. However, in some embodiments, a MAC CE may be sent from only one node. For example, when the MN determines that its signal quality is not good enough (e.g., does not meet a threshold), the MN may request the SN to send a MAC CE for itself.

[0051] In another embodiment, in the case where the NW is configured with separate CU / DU, the DU may derive the replication status information through CU notification or buffer state report (BSR) MAC CE from the UE side.

[0052] A second alternative embodiment may focus on a UE-based solution. This UE-based solution may be contrasted with a NW-based solution, which may react slower to current wireless communications than this UE-based solution due to, for example, uncertainty as to how to perform communications on other nodes. Therefore, a UE-based solution may be used for PDCP replication with multiple copies (e.g., 2+ copies). In certain embodiments, this UE-based solution may have a first step in which a PDCP entity is established or rebuilt at the UE. The establishment or reconstruction of the PDCP entity may be based on configuration information. For example, this configuration information may include any of the following: a minimum number of copies of each data radio bearer; a maximum number of copies; a cell group identifier; a serving cell identifier; a logical channel identifier; a carrier aggregation replication indicator; a dual connection replication indicator; an initial number of copies; an activation timer; a deactivation timer; a measurement window length of a data packet aggregation protocol; a copy determination threshold for determining the number of copies; a logical path selection threshold for selecting a logical path; a carrier aggregation determination threshold for determining activation of carrier aggregation replication; a dual connection determination threshold for determining activation of dual connection replication; a carrier aggregation determination threshold for determining deactivation of carrier aggregation replication; and / or a dual connection determination threshold for determining deactivation of dual connection replication.

[0053] As a second step, if the current number of replicas does not meet the reliability requirements of the data radio bearer (DRB) during the measurement window, the UE may increment the current number of replicas by 1, or activate additional CA replicas, or activate additional DC replicas.

[0054] The third step may include two alternative embodiments after the PDCP replica is incremented. As a first alternative embodiment, if the previous number of copies of the PDCP replica or the previous state of the PDCP replica transmission can meet the reliability requirements of the DRB within the measurement window, the UE may perform a decrement of the current number of copies by 1, or deactivate additional CA replication, or deactivate additional DC replication. As a second alternative embodiment, when the additional replica is activated, a timer may be started or restarted. An indicator of any of the numbers of original copies for transmission received from the upper or lower layers or a measurement performed by the PDCP layer, which means that the current measurement result of the number of any original copies is lower than the threshold configured in the configuration information, and the associated timer should be restarted. If no indication is received from the lower or upper layers for any transmission with the original number of copies, or if the measurement performed by the PDCP layer itself means that the current measurement result of the number of original copies is greater than the threshold configured in the configuration information, the additional number of copies or additional CA replication or additional DC replication should be deactivated immediately when the timer expires. In various embodiments, the UE may repeat the second step until the measurement results meet the reliability requirements of the DRB during the measurement window.

[0055] The fourth step may include two alternative embodiments. If an additional replica or an additional CA replication or an additional DC replication is activated, the first alternative embodiment may be applied to UL transmissions with multiple replicas. In this first alternative embodiment, a cache status reporting process may be triggered to notify the network (e.g., an associated BS, cell, or gNB) that the newly activated replica has data to be transmitted. If the replica or CA replication or DC replication is deactivated, the second alternative embodiment may be applied to UL transmissions with multiple replicas. In this second alternative embodiment, a cache status reporting process may be triggered to notify the network (e.g., an associated BS, cell, or gNB) of the deactivated replica (e.g., where the associated cache status and / or deactivated replica of the logical path may be calculated).

[0056] For the second and third steps, one or more of the following information can be measured to determine whether the current transmission can match the reliability requirements: channel state information of each service cell, including physical (PHY) layer measurements or higher layers other than PHY layer measurements; a successful RLC PDU transmission ratio within a specific time period (for example, related to the reliability calculation of each RLC entity); and a successful PDCP PDU transmission ratio within a specific time period (for example, related to the calculation of PDCP reliability).

[0057] A third alternative embodiment may focus on the activation or deactivation of PDCP duplication requested by the UE. For this alternative embodiment, the UE may request authorization from the NW side to perform activation or deactivation of CA duplication or DC duplication or additional duplication copies. For ease of discussion, this alternative embodiment may be described in three steps. As a first step, the UE may receive a PDCP duplication configuration from the NW side. As a second step, if the current number of copies during the measurement window does not meet the reliability requirements of the DRB, the UE may generate a MAC CE to notify the NW that an additional copy is required or that additional CA duplication is activated or that additional DC duplication is activated. In some embodiments, the MAC CE may include a logical channel ID (LCH ID) indicating an additional PDCP duplication request. In another embodiment, the MAC CE may include an indication of the number of copies or additional CA duplication or additional DC duplication. This indication may also include an LCH ID, a serving cell ID, and / or a cell group ID. In yet another embodiment, the MAC CE may include an activation / deactivation indicator (e.g., for activation / deactivation of DC duplication / CA duplication / additional duplication). As a third step, the NW may generate a MAC CE in response to receiving a requirement from the UE side. Otherwise, no feedback information is provided from the NW to the UE. In some embodiments, the MAC CE may include a logical channel ID (LCHID) indicating an additional PDCP duplication request. In another embodiment, the MAC CE may include an indication of the number of copies or additional CA duplications or additional DC duplications. This indication may be an LCH ID, a serving cell ID and / or a cell group ID. In yet another embodiment, the MAC CE may include an activation / deactivation indicator (e.g., activation / deactivation for DC duplication / CA duplication / additional duplication).

[0058] A fourth exemplary problem may involve how to ensure the reliability of UL transmission when the number of copies is predetermined. For example, when PDCP duplication is activated, PDCP may generate multiple copies for UL transmission data. Moreover, PDCP may select an associated RLC entity to transmit the generated copies. Therefore, the RLC selection scheme and / or the cell selection scheme may be used to achieve a 10^-8 error rate of NRIIOT and compensate for an unstable wireless environment.

[0059] In various embodiments, an RLC selection scheme may be used when the number of RLC entities is greater than the current number of copies. Various embodiments of the RLC selection scheme may include a UE-based solution and a NW-based solution. The UE-based solution may include a first step, a second step, and a third step. As a first step, if PDCP duplication is activated, multiple RLC entities may be configured by the UE through RRC configuration. This configuration may be based on criteria for selecting RLC entities, including a handover threshold Lout for PDCP and a handover threshold Lin for PDCP. In certain embodiments, the criteria for selecting an RLC entity may include, for example, channel state information (e.g., received signal reference power (RSRP) and / or reference signal received quality (RSRQ) and / or signal to interference and noise ratio (SINR) or other information that may indicate the current transmission state of the LCH associated with the RLC entity). As a second step, if any current measurement result of the associated available RLC entity for PDCP duplication is lower than the Lout threshold, and if the measurement result of other RLC entities is greater than the Lin threshold, the UE should select or reselect a suitable RLC entity, rather than the current RLC entity, as the RLC entity that can be used for PDCP duplication transmission. As a third step, a cache status reporting procedure may be triggered to notify the network (e.g., an associated BS, cell, or gNB) of the RLC entity handover that occurred. In some embodiments, the cache status reporting procedure may generate a cache status calculation of the handover-in RLC entity, which may be added to the cache status of the PDCP. In other embodiments, the cache status reporting procedure may generate a cache status calculation of the handover-out RLC entity, which may be subtracted from the cache status of the PDCP.

[0060] In addition to the UE-based solution, various embodiments may also provide a NW-based solution for the RLC selection scheme. This NW-based solution may reconfigure the associated RLC entity for PDCP duplication via an RRC reconfiguration message or a MAC CE message. This MAC CE message may include an RLC entity identifier, an activation / deactivation indication, or an identifier of a cell group. In some embodiments, the identifier of the RLC entity may be an LCH ID. The activation / deactivation indication may be used as needed according to the structure of the identifier of the RLC entity in the MACCE (e.g., since in some embodiments, deactivation and activation indications for the RLC entity may occur simultaneously). In addition, when a MAC CE is sent across different nodes (e.g., a MN sends a MAC CE to a UE to control an RLC entity belonging to a SN), the identifier of the cell group may be used. In various embodiments, the RRC message may include the identity of the associated RLC entity for which the PDCP duplication is activated (e.g., an LCH ID), as well as an identifier of the cell group. In some embodiments, after transmitting the relevant ACK / NACK (e.g., confirmation / non-confirmation) by receiving the RRC reconfiguration message and / or MAC CE message, the corresponding PDCP data PDU copy can be sent to the newly configured RLC entity. In an embodiment with a separate CU / DU case, the DU can derive RLC selection information (e.g., for LCH selection) through a CU notification or BSR MAC CE from the UE side. The RLC selection information may include an LCH ID, which may be associated with an activated duplicate transmission or a deactivated duplicate transmission, a cell group ID, or an LCH subset.

[0061] In various embodiments, a cell selection scheme may be used to optimize a specific replica transmission (e.g., reconfiguring the mapping relationship between LCH and cells). This cell selection scheme may include a UE-based solution or a NW-based solution. For a UE-based solution, this cell selection scheme may be used across three exemplary steps. As a first step, when PDCP duplication is activated, multiple serving cells may be configured for each replica transmission via an RRC message (e.g., via an LCH to cell restriction method). In addition, criteria for selecting one or more serving cells may be included in the RRC message (e.g., Lout and Lin thresholds). For this step, the criteria for selecting one or more serving cells may be channel state information (e.g., for measuring or determining RSRP, RSRQ, SINR, etc.) or other information that may indicate the current transmission state of the serving cell associated with each replica. The criteria may include a switching-out threshold Lout and a switching-in threshold Lin. As a second step, if the measurement of one or more current serving cells associated with a replica transmission is lower than Lout and the measurement of the serving cells from the candidate serving cell set, the UE may perform selection or reselection of one or more restricted serving cells (e.g., currently used serving cells). In addition, if the measurement of any one or more serving cells is greater than the Lin threshold, the UE may select these serving cells as restricted serving cells associated with the replica transmission. As a third step, a MAC CE may be generated to inform the NW about selecting or reselecting serving cells (e.g., as a set) used for the corresponding replica transmission configuration. Such a MAC CE may include a logical channel identifier and / or a serving cell ID, which indicates one or more serving cells that are configured as restricted associated with an LCH in a logical channel priority (LCP) process (e.g., associated with a currently used logical path).

[0062] In addition to the UE-based solution, according to various embodiments, this LCH cell selection scheme may include a NW-based solution. This NW-based solution may reconfigure the set of serving cells for a copy transmission responsible for PDCP duplicate transmission based on current channel state information or other information through an RRC message or a MAC CE message. The MACCE message may include, for example, an identifier of a logical channel and / or an identifier of a serving cell. In an embodiment with a separate CU / DU case, the DU may derive the reconfiguration of the serving cell information for the associated LCH information through a CU notification or a BSR MAC CE from the UE side. The reconfiguration of the serving cell information may include a serving cell ID activated for duplicate transmission, a serving cell ID deactivated for duplicate transmission, and an associated LCH ID and CG ID.

[0063] In view of the third and fourth exemplary problems, if the current UL transmission does not match the reliability requirements, the fifth exemplary problem may refer to UE behavior. In some embodiments, when the current UL transmission does not match the reliability requirements, RLC selection / reselection and / or service cell selection / reselection may be utilized before increasing the number of copies (e.g., activating additional PDCP copies). For example, before determining to increase the number of PDCP copies or activating additional CA or DC copies, each branch associated with the PDCP entity (e.g., a separate logical path including an RLC entity and a corresponding LCH and a corresponding air interface) may be modified to meet the reliability requirements when any of the following two situations are met. As a first case, for RLC selection / reselection, there may be no candidate RLC entity that can meet the reliability requirements. More specifically, all measurement results of the service cells associated with the candidate RLC entities may be lower than the Lin threshold. As a second case, for service cell selection / reselection for a specific copy transmission, no candidate service cell meets the reliability requirements. More specifically, the measurement results of the candidate service cell are lower than the Lin threshold.

[0064] Figure 4 4 is a flow chart illustrating a process 400 of UE behavior when the current UL transmission does not match the reliability requirement according to some embodiments. Process 400 may be performed by the UE. Note that process 400 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that in Figure 4 Additional operations (eg, blocks) may be provided before, during, and after process 400, some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0065] At operation 402, process 400 may begin by determining whether certain reliability requirements are met regarding the current transmission. As described above, these requirements may be, for example, predetermined communication requirements (e.g., communication reliability requirements). If yes, process 400 may proceed to process 400 completion 403. If no, process 400 may proceed to operation 404.

[0066] At operation 404, it is determined whether the pre-configured branch meets the requirements. A pre-configured branch may refer to a single logical path for PDCP. This pre-configured branch may, for example, have a predetermined configuration set in system information or other information accessible at system initialization or at an initial execution of process 400. If yes, process 400 may proceed to operation 406. If no, process 400 may proceed to operation 408.

[0067] At operation 408, the number of replicas may be incremented by 1. Alternatively, DC replication and / or CA replication may be performed. Incrementing the number of replicas, DC replication, or additional CA replication may be performed in a predetermined manner (eg, as set forth in the system information).

[0068] At operation 406, it may be determined whether a portion of the preconfigured branches meets certain requirements. For example, this may refer to a portion of a separate logical path for PDCP, such as a separate RLC entity, MAC entity, or serving cell. If yes, process 400 may proceed back to operation 402. If no, process 400 may proceed to operation 410.

[0069] At operation 410, the UE may adjust the preconfigured branch. The UE may adjust the preconfigured branch by, for example, replacing a separate RLC entity for another RLC entity, replacing a separate MAC entity for another MAC entity, replacing a separate serving cell for another serving cell, or replacing the entire separate branch for another branch. This other branch that may be replaced for the preconfigured branch may be, for example, a saved branch (e.g., a branch that is preconfigured for replacement in operation 410).

[0070] The sixth exemplary question may relate to UE behavior on UL transmission, where the primary path is configured per CG. This may refer to, for example, a first case in which PDCP duplication is activated and a second case in which PDCP duplication is deactivated. An embodiment in which PDCP duplication is activated may refer to a first sub-case in which only CA duplication is activated. When only CA duplication is activated, the PDCP control PDU may be transmitted only through the primary path (e.g., a predetermined path referred to as the primary path) in the cell group in which CA duplication is activated. However, when only DC duplication is activated, the PDCP control PDU may be transmitted only through the primary path belonging to the master node (MN). An embodiment in which PDCP duplication is activated may refer to a second sub-case in which only DC duplication is activated. When only DC duplication is activated, the PDCP control PDU may be transmitted through the primary path associated with the MN or the primary path associated with the secondary node (SN). An embodiment in which PDCP duplication is activated may refer to a third sub-case in which CA and DC duplication are activated. In this sub-case, the PDCP control PDU is transmitted through the primary path of the MN. Alternatively, the PDCP control PDU may be transmitted through the primary path of the MN or the primary path of the SN. Therefore, certain embodiments may disclose PDCP control PDU uplink transmission operations.

[0071] Various embodiments may also cover the case where PDCP duplication is deactivated. When PDCP duplication is deactivated, if the amount of data contained in the buffers in both the PDCP entity and the RLC entity is less than the configured threshold ULdataThreshold, the generated PDCP PDU may be transmitted in the primary path configured in the MN. Otherwise, the generated PDCP PDU may be sent via the primary path configured in the MN or the primary path configured in the SN. Therefore, certain embodiments may disclose PDCP PDU uplink transmission operations.

[0072] Figure 5A 5 is a sequence diagram illustrating a process 500 according to some embodiments, wherein the number of replicas (e.g., for PDCP duplication) is configured via radio resource control (RRC) signaling in a network-based solution. Process 500 may provide a solution to, for example, the third exemplary problem discussed above. Process 500 may be performed by UE 502A and BS 504A (e.g., NW), which may include DU 506A and CU 508A (e.g., separate DU / CU). Note that process 500 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that the process 500 may be performed in a manner that is not limited to the present disclosure. Figure 5A Additional operations (eg, blocks) may be provided before, during, and after process 500, some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0073] At operation 510, CU 508A of BS 504A may generate RRC configuration signaling (eg, configuration information via RRC) and send the RRC configuration signaling to UE 502A for controlling the number of PDCP replicas. The RRC configuration signaling may refer to any configuration, whether new or reconfigured.

[0074] At operation 512, UE 502A may transmit an ACK (e.g., confirmation) for the RRC configuration signaling to DU 506A of BS 504A. This ACK may indicate to BS 504A that the UE will begin performing UL transmissions with the configured number of replicas (e.g., after transmitting the ACK). In an optional embodiment, DU 506A may derive other PDCP replication related information (e.g., configuration of CA or / and DC replication or replicas) based on information received from CU 508A or a BSR MAC CE sent from UE 502A to DU 506A.

[0075] Figure 5B5 is a sequence diagram illustrating a process 520 according to some embodiments, wherein the number of replicas (e.g., for PDCP duplication) is configured by a medium access control (MAC) control element (CE) in a network-based solution. Process 520 may provide a solution to, for example, the third exemplary problem discussed above. Process 520 may be performed by UE 502B and BS 504B (e.g., NW), which may include DU 506B and CU 508B (e.g., separate DU / CU). Note that process 520 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that process 520 may be performed in a plurality of embodiments. Figure 5B Additional operations (eg, blocks) may be provided before, during, and after process 520 , some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0076] At operation 522, CU 508B may send configuration information to DU 506B via configuration signaling. At operation 524, UE 506B may transmit a MAC CE to the UE, the MAC CE instructing the UE to activate or reactivate CA replication, DC replication, and / or increase or decrease the number of replication copies for PDCP replication.

[0077] At operation 526, UE 502B may transmit an ACK (eg, acknowledgement) for the MAC CE to UE 506B of BS 504B. This ACK may indicate to BS 504B that the UE will begin performing UL transmissions with the configured number of copies or the configured replication method (eg, after transmitting the ACK).

[0078] Figure 5C 5 is a sequence diagram illustrating a process 540 according to some embodiments, in which the number of replicas (e.g., for PDCP duplication) is configured in a UE-based solution. Process 540 may provide a solution to, for example, the third exemplary problem discussed above. Process 540 may be performed by UE 502C and BS 504C (e.g., NW). Note that process 540 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that the process 540 may be performed in Figure 5C Additional operations (eg, blocks) are provided before, during, and after process 540 , some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0079] At operation 542, UE 502C may receive a PDCP duplication configuration (e.g., configuration information) from a BS (e.g., NW side). This PDCP duplication configuration (e.g., configuration information) may include, for example, any one of the following: a minimum number of copies of each data radio bearer; a maximum number of copies; a cell group identifier; a serving cell identifier; a logical channel identifier; a carrier aggregation duplication indicator; a dual-connectivity duplication indication; an initial number of copies; an activation timer; a deactivation timer; a measurement window length of a packet aggregation protocol; a duplication determination threshold for determining the number of copies; a logical path selection threshold for selecting a logical path; a carrier aggregation determination threshold for determining activation of carrier aggregation duplication; a dual-connectivity determination threshold for determining activation of dual-connectivity duplication; a carrier aggregation determination threshold for determining deactivation of carrier aggregation duplication; and / or a dual-connectivity determination threshold for determining deactivation of dual-connectivity duplication.

[0080] At operation 544, UE 502C may increment the number of replicas used for PDCP duplication by 1, or activate additional CA duplications or additional DC duplications, until the current number of replicas meets the reliability requirement of the DRB during the measurement window, or until the number of replicas or used branches reaches the maximum value configured to the UE from the NW. In certain embodiments, PDCP duplication may be performed similar to the techniques discussed in conjunction with the first exemplary problem, as discussed above. Moreover, in various embodiments, the UE may perform measurements and determinations to determine the reliability requirement of the DRB during the measurement window.

[0081] At operation 546, UE 502C may send a Buffer Status Report (BSR) MAC CE to BS 504C. As described above, this may be implemented, for example, in an alternative embodiment where the NW is configured with separate CUs / DUs (where the DUs may derive duplicate status information via BSR MAC CE).

[0082] Figure 5D 5 is a sequence diagram illustrating a process 560 according to some embodiments, in which the number of replicas (e.g., for PDCP duplication) is configured in a UE and BS based solution. Process 560 may provide a solution to, for example, the third exemplary problem discussed above. Process 560 may be performed by UE 502D and BS 504D (e.g., NW). Note that process 560 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that the process 560 may be performed in Figure 5D Additional operations (eg, blocks) are provided before, during, and after process 560 , some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0083] At operation 562, UE 502D may receive a PDCP duplication configuration (e.g., configuration information) from BS 504D (e.g., NW side). This PDCP duplication configuration (e.g., configuration information) may include, for example, any of the following: a minimum number of copies of each data radio bearer; a maximum number of copies; a cell group identifier; a serving cell identifier; a logical channel identifier; a carrier aggregation duplication indicator; a dual-connection duplication indicator; an initial number of copies; an activation timer; a deactivation timer; a measurement window length of a packet aggregation protocol; a duplication determination threshold for determining the number of copies; a logical path selection threshold for selecting a logical path; a carrier aggregation determination threshold for determining activation of carrier aggregation duplication; a dual-connection determination threshold for determining activation of dual-connection duplication; a carrier aggregation determination threshold for determining deactivation of carrier aggregation duplication; and / or a dual-connection determination threshold for determining deactivation of dual-connection duplication.

[0084] At operation 564, UE 502D may determine that the current number of replicas during the measurement window does not meet the reliability requirement of the DRB. Therefore, the UE may determine to send activation of an additional replication requirement (e.g., increase the number of replicas used for PDCP replication) to meet the reliability requirement. In various embodiments, the UE may perform measurements and determinations to determine the reliability requirement of the DRB during the measurement window.

[0085] At operation 566, UE 502D may transmit the PDCP duplication requirement to BS 504D in a MAC CE.

[0086] At operation 568, BS 504D may transmit ACK to UE 502D to approve UE 502D to generate multiple copies for PDCP duplication to meet reliability requirements. Alternatively, at operation 568, BS 504D may transmit NACK to disapprove UE 502D to generate multiple copies for PDCP duplication to meet reliability requirements.

[0087] Fig. 6A 6 is a sequence diagram illustrating a process 600 of determining a logical path with a set number of copies (e.g., for PDCP duplication) for determination of a radio link control (RLC) entity in a UE-based solution according to some embodiments. The process 600 may provide a solution to, for example, the fourth exemplary problem discussed above. The process 600 may be performed by a UE 602A and a BS 604B (e.g., a NW). Note that the process 600 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that the process 600 may be performed in the embodiment of the present invention. Fig. 6AAdditional operations (eg, blocks) may be provided before, during, and after process 600, some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0088] At operation 610, a PDCP duplication configuration may be received at UE 602A from BS 604A. This PDCP duplication configuration may specify how to configure multiple RLC entities. For example, this PDCP duplication configuration may include criteria for selecting an RLC entity, including a PDCP handover threshold Lout and a PDCP handover threshold Lin.

[0089] At operation 612, when any current measurement result of the associated available RLC entity for PDCP duplication is lower than Lout, the UE 602A may perform selection or reselection of a suitable RLC entity for PDCP duplication transmission. Also, when the measurement result of any RLC entity not currently used for PDCP duplication transmission is greater than the Lin threshold, the UE 602A may perform selection or reselection of a suitable RLC entity for PDCP duplication transmission.

[0090] At operation 614, UE 602A may send a buffer status report (BSR) MAC CE to BS 604A. As described above, for example, this may be implemented in embodiments where the NW is configured with separate CU / DUs (where the DUs may derive duplicate status information via the BSR MAC CE). In various embodiments, the BSR MAC CE may be used to notify BS 604A that the data buffer of the logical channel associated with the selected or reselected RLC entity may be used for data transmission.

[0091] Figure 6B 6 is a sequence diagram illustrating a process 620 of determining a logical path with a set number of replicas (e.g., for PDCP duplication) in a network (NW) based solution according to some embodiments. The process 620 may provide a solution to, for example, the fourth exemplary problem discussed above. The process 620 may be performed by a UE 602B and a BS 604B (e.g., a NW), which may include a DU 606B and a CU 608B (e.g., separate DU / CU). Note that the process 620 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that the process 620 may be performed in the embodiment of the present invention. Figure 6B Additional operations (eg, blocks) are provided before, during, and after process 620 , some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0092] At operation 622, the PDCP duplication configuration may be received at the UE 602A from the BS 604A. In an alternative embodiment with separate DU / CUs, the PDCP duplication configuration may be received at the UE 602A from the CU 608B.

[0093] At operation 624, RLC entity selection / reselection information may be received at UE 602A from BS 604A. In various embodiments, the RLC entity selection / reselection information may be determined by BS 604B based on a measurement report or a sounding reference signal (SRS) measurement result received from UE 602B. Alternatively, this RLC entity selection / reselection information may be sent in a MAC CE. In addition, this RLC entity selection / reselection information may be used for configuration or reconfiguration of the current RLC entity for UL transmission with multiple PDCP PDU copies. In an optional embodiment with separate DU / CU, the RLC entity selection / reselection information may be received at UE 602A from CU 608B.

[0094] As an alternative to operation 624, when there are separate CU / DUs, operations 626 and 628 (indicated as optional by dashed lines) may be performed. At operation 626, CU 608B may indicate to DU 606B information about RLC entity selection / reselection, which may be used for configuration or reconfiguration of the current RLC entity for UL transmission using multiple PDCP PDU copies. At operation 628, DU 606B may send a MAC CE including the RLC entity selection / reselection information to UE 602B.

[0095] At operation 630, the UE may apply the received RLC entity selection / reselection information and send an ACK to confirm reception and application of the RLC entity selection / reselection information or the received MAC CE.

[0096] In an alternative embodiment with separate DU / CU, if the RLC entity selection or reselection process is performed by RLC entity selection / reselection, DU 606B can derive RLC selection (LCH selection) information through CU notification or BSR MAC CE from UE 602B. The RLC selection information may include an LCH ID. This LCH ID may indicate an activated duplicate transmission or a deactivated duplicate transmission, a CG ID, or an LCH subset.

[0097] Figure 6C640 is a sequence diagram illustrating a process 640 of determining a logical path with a set number of replicas (e.g., for PDCP duplication) for determination of a cell (e.g., a serving cell) in a UE-based solution according to some embodiments. Process 640 may provide a solution to, for example, the fourth exemplary problem discussed above. Process 640 may be performed by UE 602A and BS 604B (e.g., a NW). Note that process 640 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that the process 640 may be performed in Figure 6C Additional operations (eg, blocks) are provided before, during, and after process 640 , some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0098] At operation 642, a PDCP duplication configuration may be received at the UE 602A from the BS 604A. The PDCP duplication configuration may identify one or more serving cells configured for each LCH via an RRC message. For example, the PDCP duplication configuration may include criteria for selecting one or more serving cells, including a switch-out threshold Lout for PDCP duplication transmission and a switch-in threshold Lin for PDCP duplication transmission.

[0099] At operation 644, when any current measurement result of the currently associated serving cell for each copy of the PDCP duplication is lower than Lout, the UE 602A may perform selection or reselection of a serving cell (e.g., a restricted serving cell) for each copy of the PDCP duplication. In addition, when the measurement result of any serving cell not currently used for PDCP duplication transmission is greater than the Lin threshold, the UE 602A may perform selection or reselection of a serving cell (e.g., a restricted serving cell) for each LCH used for the PDCP duplication.

[0100] At operation 646, UE 602A may generate and send a MAC CE to inform BS 604C of the serving cell associated with each transmission copy for PDCP duplication (e.g., determined after the processing in operation 612). UE 602A may then transmit the PDCP PDU via the selected serving cell (e.g., determined after the processing in operation 612). In other words, UE 602A may communicate using the logical path determined in operation 612.

[0101] Fig.6D6 is a sequence diagram illustrating a process 670 for determining a logical path with a set number of replicas (e.g., for PDCP duplication) for serving cell determination in a network (NW) based solution in accordance with some embodiments. Process 670 may provide a solution to, for example, the fourth exemplary problem discussed above. Process 670 may be performed by UE 602D and BS 604D (e.g., NW), which may include DU 606D and CU 608D (e.g., separate DU / CU). Note that process 670 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that process 670 may be performed in the embodiment of the present invention. Fig.6D Additional operations (eg, blocks) are provided before, during, and after process 670 , some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0102] At operation 672, the PDCP duplication configuration may be received at the UE 602D from the BS 604D. In an alternative embodiment with separate DU / CUs, the PDCP duplication configuration may be received at the UE 602D from the CU 608B.

[0103] At operation 674, RLC entity selection / reselection information may be received at UE 302A from BS 304A. In various embodiments, the RLC entity selection / reselection information may be determined by BS 604B based on a measurement report or a sounding reference signal (SRS) measurement result received from UE 602B. This RLC entity selection / reselection information may be sent in a MAC CE. In addition, this RLC entity selection / reselection information may be used for configuration or reconfiguration of a serving cell (e.g., a current or restricted serving cell) associated with each copy, such as in the case of PDCP duplication (e.g., for UL transmission with multiple PDCP PDU copies). In an optional embodiment with separate DU / CU, the RLC entity selection / reselection information may be received at UE 302A from CU 608B.

[0104] As an alternative to operation 674, when there are separate CU / DUs, operations 676 and 678 (indicated as optional by dashed lines) may be performed. At operation 676, CU 608D may indicate to DU 606D information about RLC entity selection / reselection, which may be used for configuration or reconfiguration of LCH to cell mapping relationships. These LCH to cell mapping relationships may specify a serving cell (e.g., current or restricted serving cell) associated with each LCH for PDCP duplication (e.g., for UL transmission using multiple PDCP PDU copies). At operation 678, DU 606D may send a MAC CE including serving cell selection / reselection for each copy transmission to UE 602D.

[0105] At operation 680, the UE 602D may apply the received RLC entity selection / reselection information and / or the MAC CE including the serving cell selection / reselection for each duplicate transmission. The UE 602D may then send an ACK to confirm the reception and application of the RLC entity selection / reselection information and / or the MAC CE including the LCH to cell mapping relationship.

[0106] In an optional embodiment with separate DU / CU, DU 606D may determine the configuration or reconfiguration of the serving cell (e.g., current or restricted serving cell) associated with each LCH for PDCP duplication (e.g., for UL transmission with multiple PDCP PDU copies) through a CU notification or BSR MAC CE from UE 602B. In certain embodiments, the configuration or reconfiguration of the serving cell (e.g., current or restricted serving cell) associated with each LCH for PDCP duplication (e.g., for UL transmission with multiple PDCP PDU copies) may be indicated by a serving cell ID (which is activated for duplicate transmission), an LCH ID, and / or a CG ID.

[0107] Fig. 7A 700 is a sequence diagram illustrating a process 700 of UE behavior when a current UL transmission does not match a reliability requirement according to some embodiments. Process 700 may provide a solution to, for example, the fifth exemplary problem discussed above. Process 700 may be performed by UE 702A and BS 704A (e.g., NW). Note that process 700 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that the process 700 may be performed in Fig. 7A Additional operations (eg, blocks) may be provided before, during, and after process 700, some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0108] At operation 710, the UE 702A may receive a PDCP duplication configuration from a BS (e.g., NW side). This PDCP duplication configuration may include at least one of the following: a minimum number of duplications "n", a maximum number of duplications "m", an initial PDCP duplication state (which may include: a cell group ID, a logical channel ID, a CA / DC duplication indication, and an initial number of duplications "x"), a measurement window, or a threshold value of a measurement result when establishing or reestablishing a PDCP entity.

[0109] At operation 712, UE 702A may perform measurements of a serving cell in order to determine the reliability of a logical path and / or a portion of a logical path (e.g., a PDCP entity, an RLC entity, a MAC entity, and / or a serving cell) (e.g., the reliability of a DRB during a measurement window). If the corresponding logical path and / or a portion of a logical path does not meet the reliability requirement, the UE may perform selection and / or reselection toward a logical path and / or a portion of a logical path that can meet the reliability requirement (e.g., the reliability requirement of a DRB during a measurement window). However, if there is no logical path and / or a portion of a logical path that can meet the reliability requirement, the UE may increment the number of copies used for PDCP replication by 1, or activate additional CA replication or additional DC replication until the current number of copies meets the reliability requirement of the DRB during the measurement window, or until the current number of copies and logical paths reaches a maximum value configured by the NW. In addition, in various embodiments, the UE may perform measurements and determinations during the measurement window to determine the reliability requirement of the DRB.

[0110] Figure 7B 7 is a sequence diagram illustrating a process 750 of UE and BS behavior when the current UL transmission does not match the reliability requirement according to some embodiments. Process 750 may provide a solution to, for example, the fifth exemplary problem discussed above. Process 750 may be performed by UE 702B and BS 704B (e.g., NW). Note that process 750 is merely an example and is not intended to limit the present disclosure. Therefore, it should be understood that in Figure 7B Additional operations (eg, blocks) may be provided before, during, and after process 750, some operations may be omitted, some operations may be performed concurrently with other operations, and some other operations may be briefly described herein.

[0111] At operation 752, UE 702B may receive a PDCP duplication configuration from BS 704B (e.g., NW side). This PDCP duplication configuration may include: a minimum number of duplications "n", a maximum number of duplications "m", an initial PDCP duplication state (which may include: a cell group ID, a logical channel ID, a CA / DC duplication indicator, an initial number of duplications "x"), a measurement window, or a threshold value of a measurement result when establishing or reestablishing a PDCP entity.

[0112] At operation 754, UE 702B may perform measurement of the serving cell to determine the reliability of the logical path and / or a portion of the logical path (e.g., a PDCP entity, an RLC entity, a MAC entity, and / or a serving cell) (e.g., the reliability of a DRB during a measurement window). If the corresponding logical path and / or a portion of the logical path does not meet the reliability requirement, the UE may perform selection and / or reselection toward a logical path and / or a portion of the logical path that can meet the reliability requirement (e.g., the reliability requirement of a DRB during a measurement window).

[0113] However, if there is no logical path and / or portion of a logical path that can meet the reliability requirement, the UE may determine a replication requirement (e.g., the number of copies for PDCP replication) to meet the reliability requirement. In various embodiments, the UE may perform measurements and determinations during a measurement window to determine the reliability requirement for the DRB.

[0114] At operation 756, UE 702D may transmit the PDCP duplication request to BS 504D in a MAC CE.

[0115] At operation 758, BS 704D may transmit ACK to UE 702D to approve UE 702D to generate multiple copies for PDCP duplication to meet reliability requirements. Alternatively, at operation 568, BS 704D may transmit NACK to disapprove UE 702D to generate multiple copies for PDCP duplication to meet reliability requirements.

[0116] Although various embodiments of the present invention have been described above, it should be understood that they are presented only as examples rather than as limitations. Similarly, various figures can depict example architectures or configurations, which are provided to enable those of ordinary skill in the art to understand the exemplary features and functions of the present invention. However, these people should understand that the present invention is not limited to the example architectures or configurations shown, but can be implemented using various alternative architectures and configurations. In addition, as those of ordinary skill in the art will appreciate, one or more features of an embodiment can be combined with one or more features of another embodiment described herein. Therefore, the breadth and scope of the present disclosure should not be limited by any of the above-mentioned exemplary embodiments.

[0117] It should also be understood that any reference to an element or embodiment using designations such as "first," "second," etc. herein does not generally limit the number or order of these elements. Instead, these designations may be used herein as a convenient means of distinguishing two or more elements or instances of elements. Thus, reference to a first element and a second element does not mean that only two elements can be used, or that the first element must precede the second element in some manner.

[0118] In addition, it will be understood by those skilled in the art that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, and symbols (e.g., which may be referenced in the above description) may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0119] It will be further understood by those of ordinary skill in the art that any of the various illustrative logic blocks, modules, processors, devices, circuits, methods, and functions described in conjunction with the various aspects disclosed herein may be implemented by electronic hardware (e.g., digital implementation, analog implementation, or a combination of both), firmware, various forms of programs or design codes in conjunction with instructions (which may be referred to herein as "software" or "software modules" for convenience), or any combination of these technologies. In order to clearly illustrate this interchangeability of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps have been described above in their functional aspects as a whole. Whether such functionality is implemented as hardware, firmware, or software, or a combination of these technologies, depends on the specific application and the design constraints imposed on the entire system. A skilled technician may implement the described functionality in various ways for each specific application, but such implementation decisions will not result in a departure from the scope of this disclosure.

[0120] In addition, it will be appreciated by those of ordinary skill in the art that the various illustrative logic blocks, modules, devices, components, and circuits described herein may be implemented within or performed by an integrated circuit (IC), which may include a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, or any combination thereof. The logic blocks, modules, and circuits may further include antennas and / or transceivers to communicate with various components within a network or within a device. The general purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other suitable configuration for performing the functions described herein.

[0121] If implemented in software, the function can be stored as one or more instructions or codes on a computer-readable medium. Therefore, the steps of the method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium. Computer-readable media include both computer storage media and communication media, and the communication media include any medium that can be enabled to transfer a computer program or code from one place to another. The storage medium can be any available medium that a computer can access. As an example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other medium that can be used to store the desired program code in the form of instructions or data structures and can be accessed by a computer.

[0122] In this document, the term "module" as used herein refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. In addition, for the purpose of discussion, various modules are described as discrete modules; however, as is apparent to one of ordinary skill in the art, according to embodiments of the present invention, two or more modules may be combined to form a single module that performs the associated functions.

[0123] In addition, one or more functions described in this document may be performed by computer program code stored in a "computer program product", "computer readable medium", etc., which are used herein to generally refer to media such as memory storage devices or storage units. These and other forms of computer readable media may involve storing one or more instructions for use by a processor to cause the processor to perform specified operations. These instructions, generally referred to as "computer program code" (which may be in the form of a computer program or other data package), when executed enable a computing system to perform the desired operations.

[0124] In addition, in embodiments of the present invention, memory or other storage devices and communication components may be used. It should be understood that, for the sake of clarity, the above description has described embodiments of the present invention with reference to different functional units and processors. However, it is apparent that any suitable functional distribution between different functional units, processing logic elements or domains may be used without departing from the present invention. For example, functions shown as being performed by separate processing logic elements or controllers may be performed by the same processing logic elements or controllers. Therefore, references to specific functional units are merely references to suitable means for providing the described functionality, rather than indicating a strict logical or physical structure or organization.

[0125] Various modifications to the embodiments described in this disclosure should be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the embodiments shown herein, but is to be consistent with the broadest scope consistent with the novel features and principles disclosed herein, as set forth in the above claims.

Claims

1. A method performed by a communication device, the method comprising: The communication device receives packet data convergence protocol PDCP configuration information from a communication node; For each PDCP of a data radio bearer, the communication device determines a number of logical paths based on the PDCP configuration information, wherein more than two radio link control, RLC, entities are associated with a PDCP entity of the communication device; The PDCP configuration information indicates an identifier of an RLC entity; and If the total amount of data of both the PDCP entity and the RLC entity is equal to or greater than the configured threshold ULdataThreshold, in response to PDCP duplication being deactivated, the communication device sends a PDCP data packet data unit PDU through the first primary path or the second primary path, Therein, the first primary path is configured in the master node MN and the second primary path is configured in the secondary node SN.

2. The method according to claim 1, wherein: The PDCP configuration information is received from the communication node using a medium access control MAC control element or a radio resource control RRC message.

3. The method according to claim 1, wherein: The identifier of the RLC entity includes a logical channel identifier LCH ID.

4. The method according to claim 1, wherein: The identifier of the RLC entity indicates the identity of the related RLC entity for which PDCP duplication is activated.

5. The method according to claim 1, wherein: The PDCP configuration information further indicates an activation indicator or a deactivation indicator.

6. A method performed by a communication node, the method comprising: The communication node sends packet data convergence protocol PDCP configuration information to the communication device, so that the communication device can determine the number of logical paths for each PDCP of a data radio bearer based on the PDCP configuration information, wherein more than two radio link control, RLC, entities are associated with a PDCP entity of the communication device, The PDCP configuration information indicates an identifier of an RLC entity; and If the total amount of data of both the PDCP entity and the RLC entity is equal to or greater than a configured threshold ULdataThreshold, in response to PDCP duplication being deactivated, receiving a PDCP data packet data unit PDU by the communication node through the first primary path or the second primary path, Therein, the first primary path is configured in the master node MN and the second primary path is configured in the secondary node SN.

7. The method according to claim 6, wherein the communication node sends the PDCP configuration information using a medium access control MAC control element or a radio resource control RRC message.

8. The method according to claim 6, wherein: The identifier of the RLC entity includes a logical channel identifier LCH ID.

9. The method according to claim 6, wherein: The identifier of the RLC entity indicates the identity of the related RLC entity for which PDCP duplication is activated.

10. The method according to claim 6, wherein: The PDCP configuration information further indicates an activation indicator or a deactivation indicator.

11. The method according to claim 6, further comprising: In response to the communication node comprising a centralized unit and a distributed unit: The centralized unit sends the PDCP configuration information to the distributed unit; and The distributed unit sends the PDCP configuration information to the communication device via a media access control MAC control unit.

12. A communication device comprising A processor, the processor being configured to: receiving packet data convergence protocol PDCP configuration information from a communication node; For each PDCP of the data radio bearer, determining a number of logical paths based on the PDCP configuration information, in, More than two Radio Link Control, RLC, entities are associated with a PDCP entity of the communication device, The PDCP configuration information indicates an identifier of an RLC entity; and If the total amount of data of both the PDCP entity and the RLC entity is equal to or greater than a configured threshold ULdataThreshold, in response to PDCP duplication being deactivated, a PDCP data packet data unit PDU is sent through the first primary path or the second primary path, Therein, the first primary path is configured in the master node MN and the second primary path is configured in the secondary node SN.

13. The communication device according to claim 12, wherein: The PDCP configuration information is received from the communication node using a medium access control MAC control element or a radio resource control RRC message.

14. The communication device according to claim 12, wherein: The identifier of the RLC entity includes a logical channel identifier LCH ID.

15. The communication device according to claim 12, wherein: The identifier of the RLC entity indicates the identity of the related RLC entity for which PDCP duplication is activated.

16. The communication device according to claim 12, wherein: The PDCP configuration information further indicates an activation indicator or a deactivation indicator.

17. A communication node, comprising a processor, the processor being configured to: send packet data convergence protocol (PDCP) configuration information to a communication device, so that the communication device can determine the number of logical paths for each PDCP of a data radio bearer based on the PDCP configuration information, in, More than two Radio Link Control, RLC, entities are associated with a PDCP entity of the communication device, The PDCP configuration information indicates an identifier of an RLC entity; and If the total amount of data of both the PDCP entity and the RLC entity is equal to or greater than a configured threshold ULdataThreshold, in response to PDCP duplication being deactivated, receiving a PDCP data packet data unit PDU through the first primary path or the second primary path, Therein, the first primary path is configured in the master node MN and the second primary path is configured in the secondary node SN.

18. The communication node according to claim 17, the processor is further configured to: send the PDCP configuration information using a medium access control MAC control element or a radio resource control RRC message.

19. The communication node according to claim 17, wherein: The identifier of the RLC entity includes a logical channel identifier LCH ID.

20. The communication node according to claim 17, wherein: The identifier of the RLC entity indicates the identity of the related RLC entity for which PDCP duplication is activated.

21. The communication node according to claim 17, wherein: The PDCP configuration information further indicates an activation indicator or a deactivation indicator.

22. The communication node of claim 17, wherein the processor is further configured to: In response to the communication node comprising a centralized unit and a distributed unit: Sending PDCP configuration information to the distributed unit; and The PDCP configuration information is sent to the communication device via a medium access control MAC control unit.

23. A non-transitory computer-readable medium having instructions stored thereon, which when executed by at least one processor cause the at least one processor to perform the method according to any one of claims 1-11.

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