Notification of discarded PDCP SDUs in wireless network devices

Abstract

This invention relates to notification of discarded PDCP SDUs in a wireless network device. A method is disclosed, comprising: receiving a plurality of PDCP SDUs for transmission via a Packet Data Convergence Protocol (PDCP) entity; discarding at least one PDCP SDU from the plurality of PDCP SDUs for transmission; and sending a discard notification indicating the discarding of the PDCP SDU.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 665,684, filed June 28, 2024, which is incorporated herein by reference in its entirety. Technical Field

[0003] This application generally relates to discarding PDCP SDUs in wireless network devices and providing a discard notification. Background Technology

[0004] As wireless devices send and receive larger volumes of data, making data communication more efficient becomes increasingly important. In the PDCP layer, discarding PDCP SDUs becomes crucial in certain situations. However, discarding PDCP SDUs at the transmitting PDCP entity can lead to inefficiencies in the receiving PDCP entity's operation. Therefore, when PDCP SDUs are discarded at the transmitting PDCP entity, it is desirable to improve the efficiency of the receiving PDCP entity. Summary of the Invention

[0005] Various aspects of the invention are set forth in the claims.

[0006] One or more embodiments may provide an apparatus, a computer-readable medium, a non-transitory computer-readable medium, a computer program product, and / or a method for receiving a plurality of PDCP SDUs for transmission via a Packet Data Convergence Protocol (PDCP) entity, discarding at least one PDCP SDU from the plurality of PDCP SDUs for transmission, and sending a discard notification indicating the discarding of the PDCP SDU.

[0007] One or more embodiments may provide an apparatus, a computer-readable medium, a computer program product, and / or a non-transitory computer-readable medium having means for receiving, through a Packet Data Convergence Protocol (PDCP) entity, a plurality of PDCP SDUs for transmission, discarding at least one PDCP SDU from the plurality of PDCP SDUs for transmission, and sending a discard notification indicating the discarding of the PDCP SDU.

[0008] In at least one example embodiment, the PDCP entity consists of user equipment.

[0009] In at least one example embodiment, the PDCP entity consists of a base station.

[0010] One or more example embodiments further perform receiving configuration information that indicates that drop notifications have been enabled.

[0011] In at least one example embodiment, the configuration information indicates that a drop notification, including a bitmap indication, has been enabled.

[0012] In at least one example embodiment, the configuration information indicates that drop notifications, including range indications, have been enabled.

[0013] In at least one example embodiment, the drop notification is a PDCP control PDU.

[0014] One or more example embodiments further perform the generation of a discard notification.

[0015] In at least one example embodiment, the drop notification is generated based on the drop of at least one PDCP SDU.

[0016] In at least one example embodiment, the discard notification indicates the discard of the PDCP SDU via a bitmap indication.

[0017] In at least one example embodiment, the discard notification includes a bitmap indication and a first discard PDCP SDU indication.

[0018] In at least one example embodiment, the first discarded PDCP SDU indication is a count.

[0019] In at least one example embodiment, the first discarded PDCP SDU indication is the serial number (SN).

[0020] In at least one example embodiment, each bit position indicated by the bitmap corresponds to a PDCP SDU, which is followed by a PDCP SDU indicated by a first discarded PDCP SDU.

[0021] In at least one example embodiment, the first bit in the bitmap corresponds to a PDCP SDU that immediately follows the PDCP SDU indicated by the first discarded PDCP SDU indication.

[0022] In at least one example embodiment, the nth bit in the bitmap corresponds to a PDCP SDU, which is the nth PDCP SDU following the PDCP SDU indicated by the first discarded PDCP SDU.

[0023] In at least one example embodiment, each bit value in the bitmap indicates whether the corresponding PDCP SDU is discarded.

[0024] In at least one example embodiment, each bit value in the bitmap indicates whether the corresponding PDCP SDU is discarded or sent by the PDCP entity to a lower layer for transmission.

[0025] One or more example embodiments further perform the generation of bitmap instructions.

[0026] In at least one example embodiment, generating a bitmap indication includes determining the size of the bitmap indication.

[0027] In at least one example embodiment, the size of the bitmap indication is an integer multiple of 8.

[0028] In at least one example embodiment, the size of the bitmap indicator is determined such that the bitmap includes bits corresponding to the last discarded PDCP SDU.

[0029] In at least one example embodiment, the discard notification includes a range indicator and determines the size of a bitmap indicator such that the last bit of the bitmap corresponds to a PDCP SDU immediately preceding the PDCP SDU indicated by the range indicator.

[0030] In at least one example embodiment, the discard notification indicates the discard of the PDCP SDU by means of a range indication.

[0031] In at least one example embodiment, the range indication includes a first discarded PDCP SDU indication.

[0032] In at least one example embodiment, the first discarded PDCP SDU indication is a count.

[0033] In at least one example embodiment, the first discarded PDCP SDU indication is SN.

[0034] In at least one example embodiment, the range indication includes the last discarded PDCP SDU indication.

[0035] In at least one example embodiment, the last discarded PDCP SDU indication indicates the last discarded PDCP SDU included by the range indication.

[0036] In at least one example embodiment, the last discarded PDCP SDU indication directly indicates the last discarded PDCP SDU included by the range indication.

[0037] In at least one example embodiment, the last discarded PDCP SDU is indicated by a count.

[0038] In at least one example embodiment, the last discarded PDCP SDU indication is SN.

[0039] In at least one example embodiment, the last discarded PDCP SDU indicates an indirect PDCP SDU.

[0040] In at least one example embodiment, the last discarded PDCP SDU indicates the offset from the first discarded PDCP SDU.

[0041] One or more example embodiments further perform the generation of a range indication.

[0042] In at least one example embodiment, discarding at least one PDCP SDU includes discarding multiple PDCP SDUs.

[0043] In at least one example embodiment, the multiple PDCP SDUs discarded are consecutive.

[0044] In at least one example embodiment, the drop notification includes a range indication.

[0045] One or more example embodiments further perform the determination that the multiple PDCP SDUs discarded are sufficiently consecutive.

[0046] One or more example embodiments further perform the determination based on the fact that the multiple PDCP SDUs being discarded are sufficiently consecutive and that a range indication is included in the discard notification.

[0047] In at least one example embodiment, the number of consecutively discarded PDCP SDUs exceeds a range threshold.

[0048] One or more example embodiments further perform the determination that the number of consecutively discarded PDCP SDUs exceeds a range threshold.

[0049] In at least one example embodiment, it is determined that including a range indication in the discard notification is based on determining that the number of consecutively discarded PDCP SDUs exceeds a range threshold.

[0050] In at least one example embodiment, the discarded PDCP SDUs are non-continuous.

[0051] In at least one example embodiment, the discard notification includes a bitmap indication and a corresponding first discard PDCP SDU indication.

[0052] In at least one example embodiment, the discarded multiple PDCP SDUs are sufficiently discontinuous.

[0053] In at least one example embodiment, the discard notification includes a bitmap indication and a corresponding first discard PDCP SDU indication.

[0054] One or more example embodiments further perform the determination that the multiple PDCP SDUs to be discarded are sufficiently discontinuous and that the discard notification includes a bitmap indication and a corresponding first discarded PDCP SDU indication.

[0055] One or more example embodiments further perform the determination that the multiple PDCP SDUs discarded are sufficiently discontinuous.

[0056] One or more example embodiments further perform the determination that the multiple PDCP SDUs to be discarded are sufficiently discontinuous and that the discard notification includes a bitmap indication and a corresponding first discarded PDCP SDU indication.

[0057] In at least one example embodiment, the number of consecutively discarded PDCP SDUs does not exceed a range threshold.

[0058] One or more example embodiments further perform the determination that the number of consecutively discarded PDCP SDUs does not exceed a range threshold.

[0059] One or more example embodiments further perform the determination to include a bitmap indication and a corresponding first discarded PDCP SDU indication in the discard notification based on the determination that the number of consecutively discarded PDCP SDUs does not exceed a range threshold.

[0060] In at least one example embodiment, the multiple PDCP SDUs that are discarded are PDCPSDUs belonging to the same PDCP PDU set. Attached Figure Description

[0061] To gain a more complete understanding of embodiments of the invention, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0062] Figure 1 This is a block diagram illustrating an apparatus according to at least one example embodiment;

[0063] Figure 2 This is a block diagram illustrating a wireless communication system according to at least one example embodiment;

[0064] Figure 3 It is a diagram illustrating a protocol stack according to at least one example embodiment;

[0065] Figure 4 It is a diagram illustrating a set of PDCP PDUs according to at least one example embodiment;

[0066] Figure 5 It is a flowchart illustrating an activity associated with sending a discard notification according to at least one example embodiment; and

[0067] Figure 6 This is a flowchart illustrating an activity associated with sending a discard notification according to at least one example embodiment. Detailed Implementation

[0068] Embodiments of the present invention and their potential advantages are illustrated with reference to the accompanying drawings. Figures 1 to 6 To understand.

[0069] Some embodiments will now be described more fully with reference to the accompanying drawings, which illustrate some, but not all, of the embodiments. Various embodiments of the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these examples are provided so that this disclosure will satisfy applicable legal requirements. Similar reference numerals refer to similar elements throughout. As used herein, the terms “data,” “content,” “information,” and similar terms are used interchangeably to refer to data that can be transmitted, received, and / or stored according to embodiments of the invention. Therefore, the use of any such terms should not be construed as limiting the spirit and scope of the embodiments of the invention.

[0070] Additionally, as used herein, the term 'circuit' refers to (a) a purely hardware circuit implementation (e.g., an implementation in analog and / or digital circuitry); (b) a combination of a circuit and one or more computer program products including software and / or firmware instructions stored on one or more computer-readable storage media, which work together to enable a device to perform one or more functions described herein; and (c) a circuit, such as, for example, one or more microprocessors or portions thereof, which requires software or hardware to operate, even if the software or firmware is not physically present. This definition of 'circuit' applies to all uses of the term herein, including its use in any claim. As a further example, as used herein, the term 'circuit' also includes implementations comprising one or more processors and / or portions thereof, along with accompanying software and / or firmware. As another example, the term 'circuit' as used herein also includes, for example, a baseband integrated circuit or application processor integrated circuit for a mobile phone, or a similar integrated circuit in a server, cellular network device, other network device, and / or other computing device.

[0071] As defined herein, a “non-transitory computer-readable medium” referring to a physical medium (e.g., a volatile or non-volatile memory device) can be distinguished from a “transitory computer-readable medium” referring to an electromagnetic signal.

[0072] Figure 1This is a block diagram illustrating an apparatus (such as electronic device 100) according to at least one example embodiment. However, it should be understood that the electronic device shown and described below is merely an illustration of an electronic device that can benefit from embodiments of the invention and should not be considered as limiting the scope of the invention. While electronic device 100 is illustrated and will be described below for illustrative purposes, other types of electronic devices can readily employ embodiments of the invention. Electronic device 100 may be a network node, such as a user equipment (UE) or base station, or may be a personal digital assistant (PDA), pager, mobile computer, desktop computer, television, gaming device, laptop computer, tablet computer, media player, camera, video recorder, mobile phone, global positioning system (GPS) device, automobile, self-service machine, electronic desk, and / or any other type of electronic system. Furthermore, the apparatus of at least one example embodiment need not be the entire electronic device, while in other example embodiments it may be a component or a set of components of an electronic device. For example, the device may be an integrated circuit, a set of integrated circuits, etc.

[0073] Furthermore, devices can readily employ embodiments of the invention, regardless of their intended purpose of providing mobility. In this regard, although embodiments of the invention can be described in conjunction with mobile applications, it should be understood that embodiments of the invention can be used in conjunction with a wide variety of other applications both within and outside the mobile communications industry. For example, a device can be at least part of a non-portable device, such as a large-screen television, electronic table, self-service machine, automobile, etc.

[0074] In at least one example embodiment, electronic device 100 includes a processor 110 and a memory 140. The processor 110 can be any type of processor, controller, embedded controller, processor core, etc. In at least one example embodiment, the processor 110 uses computer program code to cause the device to perform one or more actions. The memory 140 may include volatile memory (such as volatile random access memory (RAM) including a cache area for temporarily storing data) and / or other memory, for example, it may be embedded and / or may be removable non-volatile memory. Non-volatile memory may include EEPROM, flash memory, etc. The memory 140 may store any of a number of pieces of information and data. The information and data can be used by electronic device 100 to implement one or more functions of electronic device 100, such as the functions described herein. In at least one example embodiment, the memory 140 includes computer program code such that the memory and the computer program code are configured to work with the processor to cause the device to perform one or more actions described herein.

[0075] Electronic device 100 may further include transceiver 120. In at least one example embodiment, transceiver 120 is coupled to one or more antennas 130. In at least one example embodiment, processor 110 provides signals to transceiver 120 and / or receives signals from transceiver 120. Signals may include signaling information according to a communication interface standard, user voice, received data, user-generated data, etc. Transceiver 120 may operate using one or more air interface standards, communication protocols, modulation types, and access types. For illustration, the electronic transceiver 120 can operate according to second-generation (2G) wireless communication protocols such as IS-136 (Time Division Multiple Access (TDMA)), Global System for Mobile Communications (GSM) and IS-95 (Code Division Multiple Access (CDMA)), third-generation (3G) wireless communication protocols such as Universal Mobile Telecommunications System (UMTS), CDMA2000, Wideband CDMA (WCDMA) and Time Division Synchronous CDMA (TD-SCDMA), and / or according to fourth-generation (4G) wireless communication protocols such as LTE, fifth-generation (5G) protocols such as New Radio (NR) wireless network protocols such as 802.11, short-range wireless protocols such as Bluetooth, etc.

[0076] Processor 110 may include components such as circuitry for implementing audio, video, communication, navigation, logic functions, and embodiments of the invention, including one or more functions as described herein. For example, processor 110 may include components such as digital signal processor devices, microprocessor devices, various analog-to-digital converters, digital-to-analog converters, processing circuitry, and other support circuitry for performing various functions, including one or more functions as described herein. The device may perform control and signal processing functions of electronic device 100 within these devices, depending on their respective capabilities. Therefore, processor 110 may include the ability to encode and interleave messages and data prior to modulation and transmission. Processor 110 may additionally include an internal voice encoder and may include an internal data modem. Further, processor 110 may include the ability to operate one or more software programs, which may be stored in memory and, among other things, enable processor 110 to implement at least a portion of an embodiment, including one or more functions as described herein. For example, processor 110 may operate a connectivity program, such as a conventional internet browser. For example, the connection program may allow electronic device 100 to send and receive Internet content, such as location-based content and / or other web page content, according to Transmission Control Protocol (TCP), Internet Protocol (IP), User Datagram Protocol (UDP), Internet Message Access Protocol (IMAP), Post Office Protocol (POP), Simple Mail Transfer Protocol (SMTP), Wireless Application Protocol (WAP), Hypertext Transfer Protocol (HTTP), etc.

[0077] Electronic device 100 may include a user interface for providing output and / or receiving input. Electronic device 100 may include output devices, such as audio output devices (e.g., ringers, headphones, speakers), haptic output devices (e.g., vibration transducers, electronically deformable surfaces, electronically deformable structures), and visual output devices (e.g., displays and / or lights). Electronic device 100 may include input devices, such as light sensors, proximity sensors, microphones, touch sensors, force sensors, buttons, keyboards, motion sensors, magnetic field sensors, cameras, etc. In at least one example embodiment, the device receives an indication of input. The device may receive indications from sensors, drivers, individual devices, etc. The information indicating input may include information conveying the indication of input, the aspect of the indication of input, the occurrence of the indication of input, etc.

[0078] Figure 2An example of a wireless communication system 200 according to at least one exemplary embodiment is illustrated. The wireless communication system 200 includes one or more base stations 202, user equipment (UE) 201, and a core network 203. The term network node refers to a base station or a UE. In some examples, the wireless communication system 200 may be a Long Term Evolution (LTE), LTE-A Advanced (LTE-A) network, or a New Radio (NR) network. In some cases, the wireless communication system 200 may support enhanced broadband communication, ultra-reliable (i.e., mission-critical) communication, low-latency communication, and communication with low-cost and low-complexity devices. To improve the reliability of some communications (e.g., Ultra-Reliable Low-Latency Communication (URLLC) packets), the wireless communication system 200 may be configured to generate and transmit duplicate packets. In such a duplication system, a transmitting device (e.g., base station 202 or UE 201) may duplicate packets. The original packets and the duplicated packets may be transmitted to a receiving device (e.g., base station 202 or UE 201). Transmitting multiple packets containing the same information can improve the likelihood that the receiving device will receive the information included in multiple packets.

[0079] One or more base stations 202 can wirelessly communicate with one or more UEs 201 via one or more base station antennas. Each base station 202 can provide communication coverage for its respective geographic coverage area. The communication links in the wireless communication system 200 can include uplink transmissions from UE 201 to base station 202 or downlink transmissions from base station 202 to UE 201. According to various technologies, control information and data can be multiplexed on the uplink channel or the downlink channel. Control information and data can be multiplexed on the downlink channel, for example, using time division multiplexing (TDM), frequency division multiplexing (FDM), or hybrid TDM-FDM technologies. In some examples, control information transmitted during the transmission time interval (TTI) of the downlink channel can be distributed in a cascaded manner between different control areas (e.g., between a common control area and one or more UE-specific control areas).

[0080] Multiple UEs can be distributed throughout the wireless communication system 200, and each UE 201 can be fixed or mobile. UE 201 can also be referred to as a mobile station, user station, mobile unit, user unit, radio unit, remote unit, mobile device, radio device, wireless communication device, remote device, mobile user station, access terminal, mobile terminal, radio terminal, remote terminal, mobile phone, user agent, mobile client, client, or some other suitable terminology. UE 201 can also be a cellular phone, personal digital assistant (PDA), wireless modem, wireless communication device, handheld device, tablet computer, laptop computer, cordless phone, personal electronic device, handheld device, personal computer, wireless local loop (WLL) station, Internet of Things (IoT) device, Internet of Everything (IoE) device, machine-type communication (MTC) device, home appliance, automobile, etc.

[0081] In some cases, UE 201 may also be able to communicate directly with other UEs (e.g., using point-to-point (P2P) or device-to-device (D2D) protocols). One or more of a group of UEs using D2D communication may be within the cell's coverage area. Other UEs in such a group may be outside the cell's coverage area or otherwise unable to receive transmissions from base station 202. In some cases, a group of UEs communicating via D2D communication may utilize a one-to-many (1:M) system, where each UE transmits to every other UE in the group. In some cases, base station 202 facilitates the scheduling of resources for D2D communication. In other cases, D2D communication is implemented independently of base station 202.

[0082] Some UEs, such as MTC or IoT devices, can be low-cost or low-complexity devices that can provide automated communication between machines, i.e., machine-to-machine (M2M) communication. M2M or MTC can refer to data communication technologies that allow devices to communicate with each other or with a base station without human intervention. For example, M2M or MTC can refer to communication from devices that integrate sensors or instruments to measure or capture information and relay that information to a central server or application, which can then utilize or present the information to people interacting with the program or application. Some UEs can be designed to collect information or enable automated machine behavior. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based service charging.

[0083] In some cases, MTC devices can operate using half-duplex (one-way) communication at reduced peak rates. MTC devices can also be configured to enter a power-saving "deep sleep" mode when not actively communicating. In some cases, MTC or IoT devices can be designed to support mission-critical functions, and the wireless communication system can be configured to provide ultra-reliable communication to these functions.

[0084] Base station 202 can communicate with core network 203 and with one or more other base stations. For example, the base station can interface with core network 203 via a round-trip link (e.g., S1, etc.). Base stations can communicate with each other directly or indirectly (e.g., via core network 203) via other backhaul links (e.g., X2, etc.). The base station can perform radio configuration and scheduling for communicating with the UE, or it can operate under the control of a base station controller (not shown). In some examples, base station 202 can be a macro cell, small cell, hotspot, etc. The base station can also be referred to as an evolved NodeB (NB), such as eNB, gNB, etc.

[0085] Base station 202 can be connected to core network 203 via the S1 interface. The core network can be an evolved packet core (EPC), which may include at least one mobility management entity (MME), at least one serving gateway (S-GW), and at least one packet data network (PDN) gateway (P-GW). The MME can be a control node handling signaling between UE 201 and the EPC. All user Internet Protocol (IP) packets can be transmitted through the S-GW, which itself can be connected to the P-GW. The P-GW can provide IP address allocation and other functions. The P-GW can be connected to network operator IP services. Operator IP services may include the Internet, intranets, IP Multimedia Subsystem (IMS), and packet-switched (PS) streaming services.

[0086] Core network 203 can provide user authentication, access authorization, tracking, IP connectivity, and other access, routing, or mobility functions. At least some of the network devices, such as base station 202, may include sub-components, such as access network entities, which may be examples of access node controllers (ANCs). Each access network entity can communicate with several UEs through several other access network transport entities, each of which may be an example of a smart radio headend or a transmit / receive point (TRP). In some configurations, the various functions of each access network entity or base station may be distributed across various network devices (e.g., radio headends and access network controllers) or consolidated into a single network device (e.g., base station 202).

[0087] Wireless communication system 200 can operate in the ultra-high frequency (UHF) frequency region using a frequency band from 700 MHz to 2600 MHz (2.6 GHz), although some networks (e.g., wireless local area networks (WLANs)) can use frequencies up to 4 GHz. This region can also be referred to as the decimeter band because the wavelength ranges from approximately 1 decimeter to 1 meter. UHF waves can propagate primarily through the line of sight and may be blocked by buildings and environmental features. However, the waves can penetrate walls sufficiently to provide service to UEs located indoors. Compared to transmission at smaller frequencies (and longer waves) in the high frequency (HF) or very high frequency (VHF) portions of the spectrum, UHF wave transmission is characterized by smaller antennas and shorter ranges (e.g., less than 100 km). In some cases, wireless communication system 200 can also utilize the extremely high frequency (EHF) portion of the spectrum (e.g., from 30 GHz to 300 GHz). This region can also be referred to as the millimeter band because the wavelength ranges from approximately 1 millimeter to 1 centimeter. Therefore, EHF antennas can be even smaller and more closely spaced than UHF antennas. In some cases, this can facilitate the use of antenna arrays within the UE 201 (e.g., for directional beamforming). However, EHF transmissions may suffer from even greater atmospheric attenuation and shorter range than UHF transmissions.

[0088] Therefore, the wireless communication system 200 can support millimeter-wave (mmW) communication between the UE and the base station. Devices operating in the mmW or EHF bands can have multiple antennas to allow beamforming. That is, the base station 202 can use multiple antennas or antenna arrays to perform beamforming operations for directional communication with the UE 201. Beamforming (also known as spatial filtering or directional transmission) is a signal processing technique that can be used at the transmitter (e.g., the base station) to shape and / or propagate the entire antenna beam in the direction of the target receiver (e.g., the UE). This can be achieved by combining elements in the antenna array in such a way that the transmitted signal at a specific angle experiences constructive interference, while other signals experience destructive interference.

[0089] Multiple-input multiple-output (MIMO) wireless systems use a transmission scheme between a transmitter (e.g., a base station) and a receiver (e.g., a UE), where both the transmitter and receiver are equipped with multiple antennas. Some portions of the wireless communication system 200 may use beamforming. For example, base station 202 may have an antenna array with several rows and columns of antenna ports, which the base station can use for beamforming when communicating with UE 201. Signals can be transmitted multiple times in different directions (e.g., the beamforming can be different each time). The mmW receiver (e.g., the UE) can attempt multiple beams (e.g., antenna subarrays) when receiving synchronization signals.

[0090] In some cases, the antennas of base station 202 or UE 201 may be located within one or more antenna arrays that can support beamforming or MIMO operation. One or more base station antennas or antenna arrays may be placed side-by-side in an antenna assembly, such as an antenna tower. In some cases, the antennas or antenna arrays associated with base station 202 may be located in different geographical locations. Base station 202 may use multiple antennas or antenna arrays to perform beamforming operations for directional communication with UE 201.

[0091] In some cases, the wireless communication system 200 may be a packet-based network operating according to a layered protocol stack. In the user plane, communication at the bearer layer or PDCP layer may be IP-based. In some cases, the RLC layer may perform packet segmentation and reassembly for communication over logical channels. The Media Access Control (MAC) layer may perform priority processing and multiplexing logical channels into transport channels. The MAC layer may also provide retransmissions at the MAC layer using Hybrid Automatic Repeat Request (HARQ) to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide the establishment, configuration, and maintenance of RRC connections between the UE 201 and network equipment or core network 203 supporting user plane data radio bearers. At the physical (PHY) layer, transport channels may be mapped to physical channels.

[0092] The time interval in LTE or NR can be expressed in a basic time unit (which can be T). s = 1 / 30,720,000 seconds of sampling period) is used to represent time resources. Time resources can be expressed as multiples of a sampling period of 10 ms (T). f =307200T s Radio frames are organized into units, identified by System Frame Numbers (SFNs) ranging from 0 to 1023. Each frame may consist of ten 1ms subframes numbered from 0 to 9. Subframes may be further divided into two 0.5ms slots, each containing six or seven modulation symbol periods (depending on the length of the cyclic prefix preceding each symbol). Each symbol contains 2048 sample periods, excluding the cyclic prefix. In some cases, a subframe may be the minimum scheduling unit, also known as the Time Interval (TTI). In other cases, the TTI may be shorter than the subframe, or it may be dynamically selected (e.g., in short TTI bursts or in selected component carriers using short TTIs).

[0093] A resource element can consist of one symbol period and one subcarrier (e.g., a 15 kHz frequency range). A resource block can contain 12 consecutive subcarriers in the frequency domain and, for each normal cyclic prefix in an Orthogonal Frequency Division Multiplexing (OFDM) symbol, 7 consecutive OFDM symbols in the time domain (one timeslot), or it can contain 84 resource elements. The number of bits carried by each resource element can depend on the modulation scheme (the configuration of symbols selectable within each symbol period). Therefore, the more resource blocks the UE receives and the higher the modulation scheme, the higher the data rate may be.

[0094] The wireless communication system 200 can support operation on multiple cells or carriers; this feature can be referred to as carrier aggregation (CA) or multi-carrier operation. A carrier can also be referred to as a component carrier (CC), layer, channel, etc. The terms "carrier," "component carrier," "cell," and "channel" are used interchangeably herein. The UE 201 can be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation. Carrier aggregation can be used in conjunction with both frequency division duplex (FDD) component carriers and time division duplex (TDD) component carriers.

[0095] In some cases, wireless communication system 200 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, wireless communication system 200 may employ LTE Licensed Assisted Access (LTE-LAA) or LTE Unlicensed (LTE U) radio access technology or NR technology in unlicensed frequency bands (such as the 5 GHz Industrial, Scientific, and Medical (ISM) band). When operating in unlicensed radio frequency spectrum bands, wireless devices (such as base station 202 and UE 201) may employ a Listen-After-Speak (LBT) procedure to ensure the channel is open before transmitting data. In some cases, operation in unlicensed frequency bands may be based on a CA configuration combined with CC operation in licensed frequency bands. Operation in unlicensed spectrum may include downlink transmission, uplink transmission, or both. Duplexing in unlicensed spectrum may be based on FDD, TDD, or a combination of both.

[0096] Figure 3 This is a diagram illustrating a protocol stack 300 according to at least one example embodiment. Figure 3 The examples provided are merely examples and do not necessarily limit the scope of the claims.

[0097] In at least one example embodiment, the physical (PHY) layer 304 provides information transmission services to higher layers using a physical channel. The PHY layer 304 can be connected to the media access control (MAC) layer 303 located on a higher layer via a transport channel. Data can be transmitted between the MAC layer 303 and the PHY layer 304 via the transport channel. Data can be transmitted between the physical layers on the transmitting and receiving sides via the physical channel. The physical channel uses time and frequency as radio resources. In some cases, the physical channel is modulated using an orthogonal frequency division multiple access (OFDMA) scheme in the downlink and a single-carrier frequency division multiple access (SC-FDMA) scheme in the uplink.

[0098] In at least one example embodiment, MAC layer 303 provides services to the higher-layer Radio Link Control (RLC) layer 302 via a logical channel. The second-layer RLC layer 302 supports reliable data transmission. The functionality of RLC layer 302 can be implemented by function blocks of MAC layer 303. Packet Data Convergence Protocol (PDCP) layer 301 performs header compression to reduce unnecessary control information for efficient transmission of Internet Protocol (IP) packets (such as IP version 4 (IPv4) packets or IP version 6 (IPv6) packets) over a radio interface with relatively limited bandwidth.

[0099] In at least one example embodiment, the PDCP layer is implemented through PDCP entities that perform various actions of the PDCP layer. In this way, the operating network node includes one or more PDCP entities for performing PDCP layer activities. In operation, the PDCP entity receives data for transmission from higher layers in PDCP Service Data Units (SDUs). The PDCP entity performs various operations on the PDCP SDUs received from higher layers for transmission, such as header compression, uplink data compression, integrity protection, encryption, etc. The PDCP performs these operations on the received PDCP SDUs to generate PDCP Packet Data Units (PDUs), which are then sent to lower layers for transmission by means of PDCP entity transmission of PDCP SDUs.

[0100] The sending PDCP entity can track the successful transmission of PDCP SDUs to the receiving PDCP entity. For example, the sending PDCP entity can receive PDCP status reports from the receiving PDCP entity, which indicate which PDCP SDUs have been received and which have not yet been received. This allows the sending PDCP entity to take action on received and unreceived PDCP SDUs.

[0101] In at least one example embodiment, the PDCP entity has multiple SDUs for transmission received from higher layers. For example, the PDCP entity may use a buffer to store multiple PDCP SDUs for transmission.

[0102] In some cases, it may be desirable to discard one or more PDCP SDUs so that network nodes (such as UEs or base stations) do not transmit SDUs. For example, there could be a timer that tracks the amount of time since a PDCP SDU was received from an upper layer to determine whether to discard it; this timer could be called a discard timer. In such an example, the discard timer can be started or restarted when the PDCP entity receives a PDCP SDU for transmission from a higher layer. In another example, it may be desirable to discard the PDCP SDU when the discard timer expires. In this way, when circumstances prevent the transmission of multiple PDCP SDUs for transmission before the discard timer expires, the PDCP entity can discard one or more PDCP SDUs from the multiple PDCP SDUs for transmission to reduce the number of buffered PDCP SDUs for transmission.

[0103] In some cases, it may be desirable to limit the discarding of PDCP SDUs to low-importance SDUs. For example, a timer could be used to track the amount of time since a low-importance PDCP SDU was received from an upper layer to determine whether to discard it; this timer could be called a low-importance discard timer. In such an example, the low-importance discard timer could be started or restarted when the PDCP entity receives a low-importance PDCP SDU for transmission from a higher layer. In another example, it may be desirable to discard the low-importance PDCP SDU when the discard timer expires. In this way, when circumstances prevent the transmission of low-importance PDCP SDUs from multiple PDCP SDUs for transmission before the low-importance discard timer expires, the PDCP entity can discard one or more low-importance PDCP SDUs from the multiple PDCP SDUs for transmission to reduce the number of buffered low-importance PDCP SDUs for transmission. This may have the effect of providing an improved opportunity to transmit higher-importance PDCP SDUs instead of low-importance ones.

[0104] Figure 4 This is a diagram illustrating a set of PDCP PDU 400s according to at least one example embodiment. Figure 4 The examples provided are merely illustrative and do not necessarily limit the scope of the claims. In at least one example embodiment, the PDCP entity receives PDCP SDUs 401 to 410 for transmission.

[0105] In some cases, there can be multiple closely related PDCP PDUs. In such cases, these PDCP PDUs can belong to a PDCP PDU set. In this case, the PDCP SDUs corresponding to the PDCP PDUs in the PDCP PDU set also belong to the PDCP PDU set. For example, PDCP SDUs 401 to 410 and their corresponding PDCP PDUs can belong to a single PDCP PDU set. In another example, PDCP SDUs 401 to 403, 406, 408, and 410, along with their corresponding PDCP PDUs, belong to a first PDCP PDU set, while PDCP SDUs 404, 405, 407, and 409, along with their corresponding PDCP PDUs, belong to a second PDCP SDU set.

[0106] In some cases, when any PDCP SDU from the PDCP SDU set is discarded, it may be desirable to discard all PDCP SDUs in the PDCP SDU set. For example, in some cases, the receiving PDCP entity may not benefit from receiving only a subset of PDCP SDUs from the PDCP SDU set. In such examples, when one or more PDCP SDUs are discarded from the PDCP SDU set, discarding the remaining PDCP SDUs in the PDCP SDU set improves efficiency by avoiding the transmission of PDCP SDUs that the receiving PDCP entity does not need. In at least one example embodiment, when the PDCP entity discards PDCP SDUs in the PDCP SDU set, the PDCP entity discards the remaining PDCP SDUs from the PDCP SDU set used for transmission. In some cases, it may be desirable to discard only the untransmitted PDCP SDUs from the multiple PDCP SDUs used for transmission, and retain the transmitted PDCP SDUs from the multiple PDCP SDUs used for transmission. For example, if the first set of PDCP SDUs from the PDCP SDU set has been sent before being discarded, it might be desirable to discard the remaining unsent PDCP SDUs from the multiple PDCP SDUs used for transmission, and retain the first set of PDCP SDUs in the PDCPSDUs used for transmission. In this way, by retaining the first set of PDCP SDUs that has already been sent, the PDCP entity can still process PDCP status reports, which include PDCP status information related to the PDCP SDUs in the first set.

[0107] In some cases, discarding one or more PDCP SDUs can lead to inefficiency for the receiving PDCP entity. For example, the receiving PDCP entity may continue to wait to receive the discarded PDCP SDU. It may be desirable to improve the efficiency of the receiving PDCP entity by notifying it of the discarded PDCP SDU. In at least one example embodiment, the PDCP entity sends a discard notification. In at least one example embodiment, the discard notification is a notification instructing the PDCP entity to discard one or more PDCP SDUs. In at least one example embodiment, the discard notification includes information indicating one or more discarded SDUs. In at least one example embodiment, the discard notification is a PDCP control PDU. For example, the discard notification could be a PDCP SDU discard report control PDU, a PDCP SN gap report control PDU, etc.

[0108] In at least one example embodiment, the PDCP entity generates a discard notification based on the discard of at least one PDCP SDU. For example, the discard notification may be generated based on the SN associated with the discarded PDCP SDU. In such an example, the discard notification may be generated based on the SN of the discarded PDCP SDU, such that the SN is indicated by the discard notification.

[0109] There are various ways in which a discard notification can provide information indicating the discarded PDCP SDU. For example, a discard notification can indicate the discarded PDCP SDU through a count or SDN associated with the PDCP SDU. As mentioned earlier, in some cases, there can be multiple discarded PDCP SDUs. In some cases, multiple discarded PDCP SDUs can be consecutive. For example, there can be a situation where PDCP SDUs 402 to 407 are discarded from multiple PDCP SDUs 400. In such a case, the multiple discarded PDCP SDUs are consecutive. In other cases, multiple discarded PDCP SDUs can be non-consecutive. For example, there can be a situation where PDCP SDUs 401, 404, and 408 are discarded from multiple PDCP SDUs 400. In such a case, the multiple discarded PDCP SDUs are non-consecutive.

[0110] In the presence of multiple discarded PDCP SDUs, the discard notification may include a bitmap indication and / or range indication indicating the multiple discarded PDCP SDUs. In at least one example embodiment, the UE receives configuration information indicating that discard notification, bitmap indication, and / or range indication are enabled. The configuration information may be received via one or more RRC messages (such as RRC reconfiguration messages). For example, the configuration may be included in an information element included in an RRC message. In some cases, the configuration information may be included in an information element when the corresponding discard notification, bitmap indication, and / or range indication is enabled. For example, the configuration information may indicate that the corresponding discard notification, bitmap indication, and / or range indication is disabled by not being present in an information element. In at least one example embodiment, the configuration information indicates that discard notification has been enabled. In at least one example embodiment, the configuration information indicates that discard notification including a bitmap indication has been enabled. In at least one example embodiment, the configuration information indicates that discard notification including a range indication has been enabled.

[0111] In at least one example embodiment, the PDCP entity determines whether to generate a drop notification based on configuration information. In at least one example embodiment, the PDCP entity determines whether to include a bitmap indication in the drop notification based on configuration information. In at least one example embodiment, the PDCP entity determines whether to include a range indication in the drop notification based on configuration information.

[0112] In at least one example embodiment, the discard notification indicates the discarding of a PDCP SDU via a bitmap indication and a first discarded PDCP SDU indication. In at least one example embodiment, the first discarded PDCP SDU indication identifies a PDCP SDU that initiates a plurality of discarded PDCP SDUs. In at least one example embodiment, the first discarded PDCP SDU indication is a count. In at least one example embodiment, the first discarded PDCP SDU indication is a sequence number (SN).

[0113] In at least one example embodiment, the bitmap indicator is a set of bits, wherein each bit position of the bitmap indicator corresponds to a PDCP SDU following the first discarded PDCP SDU. In at least one example embodiment, each bit position of the bitmap indicator corresponds to a PDCP SDU following the first discarded PDCP SDU. In at least one example embodiment, the first bit in the bitmap corresponds to a PDCP SDU immediately following the PDCPSDU corresponding to the first discarded PDCP SDU indicator. In at least one example embodiment, the nth bit in the bitmap corresponds to a PDCP SDU that is n PDCP SDUs following the PDCP SDU corresponding to the first discarded PDCP SDU indicator. For example, the nth bit in the bitmap may correspond to a PDCP SDU having a count or a count or a SN+n of the first discarded PDCP SDU. In at least one example embodiment, each bit value in the bitmap indicator indicates whether the corresponding PDCP SDU was discarded. For example, a bit value of 1 may indicate that the corresponding PDCP SDU was discarded, and a bit value of 0 indicates that the corresponding PDCP SDU was not discarded. In another example, a bit value of 0 can indicate that the corresponding PDCP SDU was discarded, while a bit value of 1 indicates that the corresponding PDCP SDU was not discarded. In at least one example embodiment, each bit value in the bitmap indicates whether the corresponding PDCP SDU was discarded or transmitted (e.g., sent by the PDCP entity to a lower layer for transmission). For example, a bit value of 1 can indicate that the corresponding PDCP SDU was discarded, while a bit value of 0 indicates that the corresponding PDCP SDU was transmitted. In another example, a bit value of 0 can indicate that the corresponding PDCP SDU was discarded, while a bit value of 1 indicates that the corresponding PDCP SDU was transmitted.

[0114] In at least one example embodiment, the PDPC entity generates a bitmap indication. In at least one example embodiment, generating the bitmap indication includes determining the size of the bitmap indication. In some cases, it may be desirable for the bitmap indication to be an integer number of bytes. In at least one example embodiment, the size of the bitmap indication is an integer multiple of 8. In at least one example embodiment, the size of the bitmap indication is determined such that the bitmap includes bits corresponding to the last discarded PDCP SDU and fewer than 8 subsequent additional bits that make the size of the bitmap indication an integer multiple of 8.

[0115] In at least one example embodiment, the discard notification indicates the discarding of a PDCP SDU via one or more bitmap indicators and multiple discarded PDCP SDU indicators. For example, the discard notification may include multiple bitmap indicators and a first discarded PDCP SDU indicator pair. However, in some cases, to ensure the overhead associated with the bitmap, a discarded PDCP SDU may not be sufficiently close to another discarded PDCP SDU. In such cases, it may be desirable to indicate the discarded PDCP SDU via a first discarded PDCP SDU indicator, without requiring any corresponding bitmap indicator.

[0116] In at least one example embodiment, the discard notification indicates the discarding of a PDCP SDU via a range indication. In at least one example embodiment, the range indication indicates a set of consecutively discarded PDCP SDUs. In at least one example embodiment, the range indication includes a first discarded PDCP SDU indication. The first discarded PDCP SDU indication may be a count, SN, etc. In at least one example embodiment, the range indication includes a first discarded PDCP SDU indication and a last discarded PDCP SDU indication. In at least one example embodiment, the last discarded PDCP SDU indication indicates the last PDCP SDU included in the range indication. It should be noted that the term "last PDCP SDU" does not necessarily refer to the absolutely final discarded PDCP SDU, but rather to the last PDCP SDU included in the range indication. Specifically, there may be another discarded PDCP SDU in a subsequent count or SN that is not included in the range indication. For example, other discarded SDUs may be included in different range indications, bitmap indications, etc. In at least one example embodiment, the last discarded PDCP SDU indication directly indicates the last PDCP SDU of the range indication. For example, the last discarded PDCP SDU indication could be a count, SN, etc., identifying the last discarded PDCP SDU. In at least one example embodiment, the last discarded PDCPSDU indication indirectly indicates the PDCP SDU. For example, the last discarded PDCP SDU indication could be a PDCP SDU indicated by an offset from the first discarded PDCPSDU. In at least one example embodiment, the PDCP entity generates a range notification.

[0117] In at least one example embodiment, a discard notification indicates the discarding of multiple PDCP SDUs by a combination of one or more range indicators, one or more bitmap indicators, and one or more corresponding first discarded PDCP SDU indicators. For example, a discard notification may indicate the discarding of a first plurality of PDCP SDUs by one or more range indicators, and may indicate the discarding of a second plurality of PDCP SDUs by one or more bitmap indicators and one or more corresponding first discarded PDCP SDU indicators. In some cases, there may be a number of non-contiguous discarded PDCP SDUs followed by a number of consecutively discarded PDCP SDUs. In such cases, the discard notification may include a first discarded PDCP SDU indicator and a corresponding bitmap indicator for the non-contiguous discarded PDCP SDUs, and a range indicator for the consecutively discarded PDCP SDUs. In at least one example embodiment, the size of the bitmap indicator is determined such that the last bit of the bitmap corresponds to a discarded PDCP SDU immediately preceding the PDCP SDU included in the range indicator.

[0118] Figure 5 This is a flowchart illustrating an activity 500 associated with sending a discard notification according to at least one example embodiment. In at least one example embodiment, there is a set of operations related to... Figure 5 The corresponding activity. Device (e.g.) Figure 1 The electronic device 100 or a portion thereof can utilize this group of operations. The device may include components for performing such operations, including, for example... Figure 1 The processor 110. In an example embodiment, the device (e.g., Figure 1 The electronic device 100) uses a memory (e.g., containing computer code) to... Figure 1 The computer code is configured to be transformed using a memory 140, and the memory 140 is used to transform the computer code. Figure 1 The processor 110 works together to enable the device to perform Figure 5 A set of operations.

[0119] At block 501, the device receives multiple PDCP SDUs for transmission. For example, the multiple PDCP SDUs may be received by the device's PDCP entity, and may be received from a higher layer (such as a layer above the PDCP layer).

[0120] At box 502, the device discards at least one PDCP SDU from the plurality of PDCP SDUs used for transmission. Discarding can be similar to... Figure 3 and Figure 4 The described discard.

[0121] At box 503, the device sends a discard notification. As previously described, the discard notification can indicate the discard of the PDCP SDU, similar to the notification regarding... Figure 4 The discussion continues. For example, the content of a discard notification could be based on the discard of at least one PDCP SDU.

[0122] Figure 6 This is a flowchart illustrating an activity 600 associated with sending a drop notification according to at least one example embodiment. In at least one example embodiment, there is a set of operations related to... Figure 6 The corresponding activity. Device (e.g.) Figure 1 The electronic device 100 or a portion thereof can utilize this group of operations. The device may include components for performing such operations, including, for example... Figure 1 The processor 110. In an example embodiment, the device (e.g., Figure 1 The electronic device 100) uses a memory (e.g., containing computer code) to... Figure 1 The computer code is configured to be transformed using a memory 140, and the memory 140 is used to transform the computer code. Figure 1 The processor 110 works together to enable the device to perform Figure 6 A set of operations.

[0123] As previously described, a drop notification may include a bitmap indication or a range indication. However, there are cases where a bitmap indication is more effective than a range indication, and other cases where a range indication is more effective than a bitmap indication. For example, if there is a large number of consecutively dropped PDCP SDUs, a range indication may be more effective than a bitmap indication. However, if the number of consecutively dropped PDCP SDUs is low, a bitmap indication may be more effective than a range indication. In at least one example embodiment, when the combination of a bitmap indication and a first dropped PDCP SDU is larger than the corresponding range indication, the device determines to use a range notification to indicate a group of consecutively dropped PDCP SDUs, rather than the combination of a bitmap indication and a first dropped PDCP SDU. In at least one example embodiment, when the combination of a bitmap indication and a first dropped PDCP SDU is larger than the corresponding range indication, a group of consecutively dropped PDCP SDUs is considered sufficiently consecutive. In at least one example embodiment, when the combination of range indications is larger than the corresponding bitmap indication and a first dropped PDCP SDU, the device determines to use the combination of a bitmap indication and a first dropped PDCP SDU to indicate a group of consecutively dropped PDCP SDUs, rather than a range notification. In at least one example embodiment, a set of consecutively discarded PDCP SDUs is considered sufficiently discontinuous when the combination of range indications is greater than the corresponding bitmap indication and the first discarded PDCP SDU.

[0124] In at least one example embodiment, the apparatus determines whether to include a bitmap indication or a range indication based on whether the discarded PDCP SDUs are sufficiently contiguous. In at least one example embodiment, determining whether the discarded PDCP SDUs are sufficiently contiguous includes determining whether the number of consecutive PDCP SDUs exceeds a range threshold. For example, when the number of consecutive PDCP SDUs is less than the range threshold (and in some embodiments, also includes a case where the number of consecutive PDCP SDUs equals the range threshold), the apparatus may determine that the discarded PDCP SDUs are sufficiently discontinuous for the purpose of discard notification, and when the number of consecutive PDCP SDUs is greater than the range threshold (and in some embodiments, also includes a case where the number of consecutive PDCP SDUs equals the range threshold), the apparatus may determine that the discarded PDCP SDUs are sufficiently contiguous for the purpose of discard notification. The range threshold may be a number corresponding to the number of consecutive discarded SDUs, which, for the range indication, must be fewer bits (or fewer octets) than the combination of a bitmap indication and a corresponding first discarded PDCP SDU indication.

[0125] At frame 601, the device receives multiple PDCP SDUs for transmission, similar to the information regarding... Figure 5 As described in box 501.

[0126] At box 602, the device discards at least one PDCP SDU from the plurality of PDCP SDUs used for transmission, similar to the description of... Figure 5 As described in box 502.

[0127] At block 603, the apparatus determines whether the discarded PDCP SDUs are sufficiently contiguous. If the discarded PDCP SDUs are sufficiently contiguous, the process continues to block 604. If the discarded PDCP SDUs are sufficiently discontinuous, the process continues to block 605. As previously described, determining whether the discarded PDCP SDUs are sufficiently contiguous includes determining whether the number of consecutive PDCP SDUs among the discarded PDCP SDUs exceeds a range threshold. Therefore, in at least one example embodiment, at block 603, the apparatus determines whether the number of consecutive PDCP SDUs among the discarded PDCP SDUs exceeds a range threshold. In such an embodiment, if the number of consecutive PDCP SDUs among the discarded PDCP SDUs exceeds the range threshold, the process continues to block 604, and if the number of consecutive PDCP SDUs among the discarded PDCP SDUs does not exceed the range threshold, the process continues to block 605.

[0128] At box 604, the device includes a range indication in the discard notification to indicate the discard of multiple PDCP SDUs.

[0129] At box 605, the device includes a bitmap indication and a corresponding first discarded PDCP SDU indication in the discard notification to indicate the discard of multiple PDCP SDUs.

[0130] Embodiments of the present invention can be implemented in software, hardware, application logic, or a combination of software, hardware, and application logic. The software, application logic, and / or hardware may reside on a device, a separate device, or multiple separate devices. If desired, portions of the software, application logic, and / or hardware may reside on a device, portions of the software, application logic, and / or hardware may reside on a separate device, and portions of the software, application logic, and / or hardware may reside on multiple separate devices. In exemplary embodiments, the application logic, software, or instruction set is held on any of a variety of conventional computer-readable media.

[0131] If necessary, the different functions discussed herein can be executed in different orders and / or in parallel with each other. Furthermore, if necessary, one or more of the functions described above can be optional or can be combined.

[0132] Although various aspects of the invention are set forth in the independent claims, other aspects of the invention include other combinations of features from the described embodiments and / or features of dependent claims having the features of the independent claims, and not only the combinations expressly set forth in the claims.

[0133] This document also notes that while exemplary embodiments of the invention have been described above, these descriptions should not be interpreted in a limiting sense. Rather, variations and modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

1. An apparatus for notifying the disposal of a PDCP SDU, comprising: At least one processor; as well as The device includes at least one memory containing a computer program, the memory and the computer program being configured to work with the processor to cause the device to perform at least the following operations: Receive Radio Resource Control (RRC) messages, which include configuration information for enabling drop notification, configuration information for including bitmap information in the drop notification, and configuration information for including range indication in the drop notification; The device receives multiple PDCP Service Data Units (SDUs) for transmission via the Packet Data Convergence Protocol (PDCP) entity. Discard multiple PDCP SDUs from the multiple PDCP SDUs used for transmission; Based on the configuration information for enabling drop notifications, a drop notification is generated indicating the drop of the multiple PDCP SDUs, including: Determine whether the following conditions are met: the plurality of PDCP SDUs include a first plurality of non-continuously discarded SDUs, wherein the number of continuously discarded PDCP SDUs does not exceed a range threshold, and then a second plurality of continuously discarded SDUs, wherein the number of continuously discarded PDCPSDUs exceeds a range threshold; Based on configuration information that enables the inclusion of bitmap information in the drop notification and the determination that the number of consecutively dropped PDCP SDUs in the first plurality of non-contiguously dropped SDUs does not exceed a range threshold, a bitmap indication and a first dropped PDCPSDU indication are generated to be included in the drop notification, wherein the first bit in the bitmap corresponds to the PDCP SDU immediately following the PDCP SDU indicated by the first dropped PDCPSDU indication. Based on configuration information enabling the inclusion of a range indication in the drop notification and a determination that the number of consecutively dropped PDCP SDUs in the second plurality of consecutively dropped SDUs exceeds a range threshold, a range indication is generated to be included in the drop notification, wherein the range threshold includes an indication of the last dropped PDCP SDU, wherein the size of the bitmap indication is determined such that the last bit of the bitmap corresponds to the PDCPSDU immediately preceding the PDCP SDU indicated by the range indication; and Send the discard notification, which includes a bitmap indication, a first discarded PDCP SDU indication, and a range indication including a last discarded PDCP SDU indication.

2. The apparatus of claim 1, wherein each bit position of the bitmap indication corresponds to a PDCP SDU, the PDCP SDU being followed by a PDCP SDU indicated by the first discarded PDCP SDU indication, and each bit value in the bitmap indication indicates whether the corresponding PDCP SDU has been discarded.

3. A method for notifying the discarding of a PDCP SDU, comprising: Receive Radio Resource Control (RRC) messages, which include configuration information for enabling drop notification, configuration information for including bitmap information in the drop notification, and configuration information for including range indication in the drop notification; Receive multiple PDCP Service Data Units (SDUs) for transmission through the Packet Data Convergence Protocol (PDCP) entity. Discard multiple PDCP SDUs from the multiple PDCP SDUs used for transmission; Based on the configuration information for enabling drop notifications, a drop notification is generated indicating the drop of the multiple PDCP SDUs, including: Determine whether the following conditions are met: the plurality of PDCP SDUs include a first plurality of non-continuously discarded SDUs, wherein the number of continuously discarded PDCP SDUs does not exceed a range threshold, and then a second plurality of continuously discarded SDUs, wherein the number of continuously discarded PDCPSDUs exceeds a range threshold; Based on configuration information that enables the inclusion of bitmap information in the drop notification and the determination that the number of consecutively dropped PDCP SDUs in the first plurality of non-contiguously dropped SDUs does not exceed a range threshold, a bitmap indication and a first dropped PDCPSDU indication are generated to be included in the drop notification, wherein the first bit in the bitmap corresponds to the PDCP SDU immediately following the PDCP SDU indicated by the first dropped PDCPSDU indication. Based on configuration information enabling the inclusion of a range indication in the drop notification and a determination that the number of consecutively dropped PDCP SDUs in the second plurality of consecutively dropped SDUs exceeds a range threshold, a range indication is generated to be included in the drop notification, wherein the range threshold includes an indication of the last dropped PDCP SDU, wherein the size of the bitmap indication is determined such that the last bit of the bitmap corresponds to the PDCPSDU immediately preceding the PDCP SDU indicated by the range indication; and Send the discard notification, which includes a bitmap indication, a first discarded PDCP SDU indication, and a range indication including a last discarded PDCP SDU indication.

4. The method of claim 3, wherein each bit position of the bitmap indication corresponds to a PDCP SDU, the PDCP SDU being followed by a PDCP SDU indicated by the first discarded PDCP SDU indication, and each bit value in the bitmap indication indicates whether the corresponding PDCP SDU has been discarded.

5. At least one non-transitory computer-readable medium, said medium being encoded with a computer program that, when executed by a processor, performs the following: Receive Radio Resource Control (RRC) messages, which include configuration information for enabling drop notification, configuration information for including bitmap information in the drop notification, and configuration information for including range indication in the drop notification; Receive multiple PDCP Service Data Units (SDUs) for transmission through the Packet Data Convergence Protocol (PDCP) entity. Discard multiple PDCP SDUs from the multiple PDCP SDUs used for transmission; Based on the configuration information for enabling drop notifications, a drop notification is generated indicating the drop of the multiple PDCP SDUs, including: Determine whether the following conditions are met: the plurality of PDCP SDUs include a first plurality of non-continuously discarded SDUs, wherein the number of continuously discarded PDCP SDUs does not exceed a range threshold, and then a second plurality of continuously discarded SDUs, wherein the number of continuously discarded PDCPSDUs exceeds a range threshold; Based on configuration information that enables the inclusion of bitmap information in the drop notification and the determination that the number of consecutively dropped PDCP SDUs in the first plurality of non-contiguously dropped SDUs does not exceed a range threshold, a bitmap indication and a first dropped PDCPSDU indication are generated to be included in the drop notification, wherein the first bit in the bitmap corresponds to the PDCP SDU immediately following the PDCP SDU indicated by the first dropped PDCPSDU indication. Based on configuration information enabling the inclusion of a range indication in the drop notification and a determination that the number of consecutively dropped PDCP SDUs in the second plurality of consecutively dropped SDUs exceeds a range threshold, a range indication is generated to be included in the drop notification, wherein the range threshold includes an indication of the last dropped PDCP SDU, wherein the size of the bitmap indication is determined such that the last bit of the bitmap corresponds to the PDCPSDU immediately preceding the PDCP SDU indicated by the range indication; and Send a discard notification, which includes a bitmap indication, a first discarded PDCP SDU indication, and a range indication including the last discarded PDCP SDU indication.

Images