Apparatus, method and computer program

Abstract

There is provided an apparatus comprising: means for receiving, at a user equipment, at least one downlink data transmission from a network node; means for determining that decoding of the at least one downlink data transmission at the user equipment is unsuccessful; means for determining soft buffer information based on a determination that decoding of the at least one downlink data transmission at the user equipment is unsuccessful and based at least in part on the downlink data transmission; means for providing soft buffer information from the user equipment to the network node; and means for receiving a schedule for another downlink data transmission, wherein the schedule for another downlink data transmission depends on the provided soft buffer information.

Description

Technical Field

[0001] The present application relates to a method, an apparatus, a system and a computer program, and in particular but not exclusively to UE assistance information. Background Art

[0002] A communication system can be viewed as a facility for enabling communication sessions between two or more entities such as user terminals, base stations and / or other nodes by providing carrier waves between the various entities involved in the communication path. A communication system can be provided, for example, by means of a communication network and one or more compatible communication devices. A communication session may include, for example, the communication of data for carrying communications such as voice, video, electronic mail (email), text messaging, multimedia and / or content data. Non-limiting examples of the services provided include two-way or multi-way calls, data communications or multimedia services, and access to data network systems such as the Internet.

[0003] In a wireless communication system, at least a portion of a communication session between at least two stations occurs over a wireless link. Examples of wireless systems include public land mobile networks (PLMNs), satellite-based communication systems, and different wireless local networks, such as wireless local area networks (WLANs). Some wireless systems can be divided into cells and are therefore often referred to as cellular systems.

[0004] A user can access the communication system with the aid of an appropriate communication device or terminal. The user's communication device may be referred to as a user equipment (UE) or user device. The communication device is provided with appropriate signal receiving and sending means for implementing communication, such as implementing access to a communication network or communicating directly with other users. The communication device may access a carrier provided by a site (e.g., a base station of a cell) and send and / or receive communications on the carrier.

[0005] Communication systems and associated equipment typically operate according to a given standard or specification that specifies what the various entities associated with the system are allowed to do and how it should be achieved. Communication protocols and / or parameters required for the connection are also typically defined. An example of a communication system is the Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN) (3G radio). Other examples of communication systems are the Long Term Evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio access technology and the so-called 5G or New Radio (NR) networks. NR is standardized by the Third Generation Partnership Project (3GPP). Other examples of communication systems include 5G-Advanced (NR Rel-18 and above) and 6G. Summary of the invention

[0006] In a first aspect, an apparatus is provided, comprising: a component for receiving at least one downlink data transmission from a network node at a user equipment; a component for determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful; a component for determining soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and at least partially based on the downlink data transmission; a component for providing soft buffer information from the user equipment to the network node; and a component for receiving scheduling for another downlink data transmission, wherein the scheduling for the another downlink data transmission depends on the provided soft buffer information.

[0007] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0008] Each of the at least one data transmission may be associated with a given hybrid automatic repeat request (HARQ) process.

[0009] The indication may be provided as HARQ feedback or uplink control information.

[0010] This indication may be provided as a separate bit from the HARQ feedback.

[0011] This indication may be jointly encoded with the HARQ feedback.

[0012] The apparatus may include means for determining whether to store soft bits for a downlink HARQ process based on at least one of a priority associated with the downlink data transmission, whether the downlink data transmission was successfully decoded, or available capacity of a soft buffer memory.

[0013] The soft buffer information may include an indication of available soft buffer capacity.

[0014] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0015] The indication may be provided via HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0016] The apparatus may include means for receiving, at a user equipment, a configuration from a network node to provide soft buffer information.

[0017] The apparatus may include means for receiving the configuration using radio resource control signaling or medium access control control elements.

[0018] The configuration may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0019] The apparatus may include means for providing, from the user equipment to the network node, an indication of the user equipment soft buffer information reporting capability; and means for receiving, at the user equipment, a configuration from the network node in response to providing the soft buffer information.

[0020] The received scheduling for another downlink data transmission may depend on at least one of: receiving a configuration of modified scheduling parameters for using a smaller number of HARQ processes, receiving an indication not to save soft buffer values ​​for the corresponding downlink data transmission, or receiving scheduling for another downlink data transmission on a smaller number of HARQ processes.

[0021] In a second aspect, a device is provided, comprising: a component for providing at least one downlink data transmission from a network node to a user equipment; a component for receiving soft buffer information determined based on at least one downlink data transmission from the user equipment at the network node; and a component for determining another downlink data transmission scheduling based on the received soft buffer information.

[0022] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0023] The indication may be provided as HARQ feedback or uplink control information.

[0024] This indication may be provided as a separate bit from the HARQ feedback.

[0025] This indication may be jointly encoded with the HARQ feedback.

[0026] The soft buffer information may include an indication of available soft buffer capacity.

[0027] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0028] The indication may be provided via HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0029] The apparatus may include means for providing an indication from a network node to a user equipment to provide soft buffer information.

[0030] The apparatus may include means for providing the indication using radio resource control signaling or a medium access control control element.

[0031] The indication may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0032] The apparatus may include means for receiving, from the user equipment to the network node, an indication of a user equipment soft buffer information reporting capability; and means for providing, at the user equipment, an indication from the network node in response to providing the soft buffer information.

[0033] The component for determining the transmission scheduling includes a component for at least one of the following: providing an indication to the user equipment that soft bits for another downlink data transmission should not be stored; configuring the user equipment to use a smaller number of HARQ processes, modified scheduling parameters, or scheduling downlink data transmission to the user equipment on a smaller number of HARQ processes.

[0034] In a third aspect, a method is provided, comprising: receiving at least one downlink data transmission from a network node at a user equipment; determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful; determining soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and at least partially based on the downlink data transmission; providing soft buffer information from the user equipment to the network node and receiving scheduling for another downlink data transmission, wherein the scheduling for the other downlink data transmission depends on the provided soft buffer information.

[0035] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0036] Each of the at least one data transmission may be associated with a given hybrid automatic repeat request (HARQ) process.

[0037] The indication may be provided as HARQ feedback or uplink control information.

[0038] This indication may be provided as a separate bit from the HARQ feedback.

[0039] This indication may be jointly encoded with the HARQ feedback.

[0040] The method may include determining whether to store soft bits for a downlink HARQ process based on at least one of: a priority associated with the downlink data transmission, whether the downlink data transmission was successfully decoded, or an available capacity of a soft buffer memory.

[0041] The soft buffer information may include an indication of available soft buffer capacity.

[0042] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0043] The indication may be provided via HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0044] The method may include receiving, at a user equipment, a configuration from a network node to provide soft buffer information.

[0045] The method may include receiving the configuration using radio resource control signaling or a medium access control control element.

[0046] The configuration may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0047] The method may comprise providing, from the user equipment to the network node, an indication of a soft buffer information reporting capability of the user equipment; and receiving, at the user equipment, a configuration from the network node in response to providing the soft buffer information.

[0048] Scheduling for receiving another downlink data transmission may depend on at least one of: receiving a configuration of modified scheduling parameters for using a smaller number of HARQ processes, receiving an indication not to save soft buffer values ​​for the corresponding downlink data transmission, or receiving scheduling for another downlink data transmission on a smaller number of HARQ processes.

[0049] In a fourth aspect, a method is provided, comprising: providing at least one downlink data transmission from a network node to a user equipment; receiving, at the network node, soft buffer information determined based on the at least one downlink data transmission from the user equipment; and determining another downlink data transmission scheduling based on the received soft buffer information.

[0050] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0051] The indication may be provided as HARQ feedback or uplink control information.

[0052] This indication may be provided as a separate bit from the HARQ feedback.

[0053] This indication may be jointly encoded with the HARQ feedback.

[0054] The soft buffer information may include an indication of available soft buffer capacity.

[0055] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0056] The indication may be provided via HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0057] The method may comprise providing, from the network node to the user equipment, an indication to provide the soft buffer information.

[0058] The method may include providing the indication using radio resource control signaling or a medium access control control element.

[0059] The indication may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0060] The method may include: receiving, from the user equipment to the network node, an indication of a soft buffer information reporting capability of the user equipment; and providing, at the user equipment, an indication from the network node in response to providing the soft buffer information.

[0061] Determining the transmission scheduling may include at least one of the following: providing an indication to the user equipment that soft bits used for another downlink data transmission should not be stored; configuring the user equipment to use a smaller number of HARQ processes, modified scheduling parameters, or scheduling downlink data transmission to the user equipment on a smaller number of HARQ processes.

[0062] In a fifth aspect, a device is provided, comprising: at least one processor; and at least one memory storing instructions, which, when executed by the at least one processor, causes the device to at least: receive at least one downlink data transmission from a network node at a user equipment; determine that decoding of at least one downlink data transmission at the user equipment is unsuccessful; determine soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and at least partially based on the downlink data transmission; provide the soft buffer information to the network node from the user equipment and receive scheduling for another downlink data transmission, wherein the scheduling for the other downlink data transmission depends on the provided soft buffer information.

[0063] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0064] Each of the at least one data transmission may be associated with a given hybrid automatic repeat request (HARQ) process.

[0065] The indication may be provided via HARQ feedback or uplink control information.

[0066] This indication may be provided as a separate bit from the HARQ feedback.

[0067] This indication may be jointly encoded with the HARQ feedback.

[0068] The apparatus may determine whether to store soft bits for a downlink HARQ process based on at least one of: a priority associated with the downlink data transmission, whether the downlink data transmission is successfully decoded, or an available capacity of a soft buffer memory.

[0069] The soft buffer information may include an indication of available soft buffer capacity.

[0070] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0071] The indication may be provided with HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0072] The apparatus may be configured to provide soft buffer information by receiving, at a user equipment, from a network node.

[0073] The apparatus may receive the configuration using radio resource control signaling or a medium access control control element.

[0074] The configuration may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0075] The apparatus may be provided, from the user equipment, to the network node, an indication of the user equipment soft buffer information reporting capability, and receiving, at the user equipment, a configuration from the network node in response to providing the soft buffer information.

[0076] The received scheduling for another downlink data transmission may depend on at least one of: receiving a configuration of modified scheduling parameters for using a smaller number of HARQ processes, receiving an indication not to save soft buffer values ​​for the corresponding downlink data transmission, or receiving a scheduling for another downlink data transmission on a smaller number of HARQ processes.

[0077] In a sixth aspect, a device is provided, comprising: at least one processor; and at least one memory storing instructions which, when executed by the at least one processor, cause the device to at least: provide at least one downlink data transmission from a network node to a user equipment; receive soft buffer information determined based on at least one downlink data transmission from the user equipment at the network node; and determine another downlink data transmission scheduling based on the received soft buffer information.

[0078] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0079] The indication may be provided via HARQ feedback or uplink control information.

[0080] This indication may be provided as a separate bit from the HARQ feedback.

[0081] This indication may be jointly encoded with the HARQ feedback.

[0082] The soft buffer information may include an indication of available soft buffer capacity.

[0083] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0084] The indication may be provided via HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0085] The means may be provided from a network node to a user equipment with an indication to provide soft buffer information.

[0086] The apparatus may be configured to provide the indication using radio resource control signaling or a medium access control control element.

[0087] The indication may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0088] The apparatus may be configured to receive, from the user equipment to the network node, an indication of a user equipment soft buffer information reporting capability, and provide, at the user equipment, an indication from the network node in response to providing the soft buffer information.

[0089] Determining the transmission scheduling may include at least one of the following: providing an indication to the user equipment that soft bits for another downlink data transmission should not be stored; configuring the user equipment to use a smaller number of HARQ processes, modified scheduling parameters, or scheduling downlink data transmission to the user equipment on a smaller number of HARQ processes.

[0090] In a seventh aspect, a computer-readable medium is provided, comprising instructions, which, when executed by an apparatus, cause the apparatus to at least perform the following operations:

[0091] receiving at least one downlink data transmission from a network node at a user equipment;

[0092] Determine that decoding of at least one downlink data transmission at the user equipment is unsuccessful, determine soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and at least partially based on the downlink data transmission, provide the soft buffer information to the network node from the user equipment and receive scheduling for another downlink data transmission, wherein the scheduling for the another downlink data transmission depends on the provided soft buffer information.

[0093] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0094] Each of the at least one data transmission may be associated with a given hybrid automatic repeat request (HARQ) process.

[0095] The indication may be provided via HARQ feedback or uplink control information.

[0096] This indication may be provided as a separate bit from the HARQ feedback.

[0097] This indication may be jointly encoded with the HARQ feedback.

[0098] The apparatus may be operable to determine whether to store soft bits for a downlink HARQ process based on at least one of: a priority associated with the downlink data transmission, whether the downlink data transmission is successfully decoded, or an available capacity of a soft buffer memory.

[0099] The soft buffer information may include an indication of available soft buffer capacity.

[0100] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0101] The indication may be provided with HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0102] The apparatus may be caused to perform receiving, from a network node at a user equipment, a configuration to provide soft buffer information.

[0103] The apparatus may be configured to receive signals using radio resource control signaling or medium access control elements.

[0104] The configuration may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0105] The apparatus may be executable to provide, from a user equipment to a network node, an indication of a user equipment soft buffer information reporting capability, and to receive, at the user equipment, a configuration from the network node in response to providing the soft buffer information.

[0106] The received scheduling for another downlink data transmission may depend on at least one of: receiving a configuration of modified scheduling parameters for using a smaller number of HARQ processes, receiving an indication not to save soft buffer values ​​for the corresponding downlink data transmission, or receiving scheduling for another downlink data transmission on a smaller number of HARQ processes.

[0107] In an eighth aspect, a computer-readable medium is provided, comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least the following operations: provide at least one downlink data transmission from a network node to a user equipment; receive, at the network node, soft buffer information determined based on at least one downlink data transmission from the user equipment; and determine another downlink data transmission schedule based on the received soft buffer information.

[0108] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

[0109] The indication may be provided via HARQ feedback or uplink control information.

[0110] This indication may be provided as a separate bit from the HARQ feedback.

[0111] This indication may be jointly encoded with the HARQ feedback.

[0112] The soft buffer information may include an indication of available soft buffer capacity.

[0113] The soft buffer information may include an indication of available soft buffer capacity relative to at least one threshold capacity value.

[0114] The indication may be provided via HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0115] The apparatus may be caused to perform providing, from a network node to a user equipment, an indication to provide soft buffer information.

[0116] The means may be performed using radio resource control signaling or medium access control control elements to provide the indication.

[0117] The indication may include configuration of soft buffer information reporting or activation of soft buffer information reporting.

[0118] The apparatus may be operable to: receive from the user equipment to the network node an indication of the user equipment soft buffer information reporting capability; and provide, at the user equipment, an indication from the network node in response to means for providing the soft buffer information.

[0119] Determining the transmission scheduling may include at least one of the following: providing an indication to the user equipment that soft bits for another downlink data transmission should not be stored; configuring the user equipment to use a smaller number of HARQ processes, modified scheduling parameters, or scheduling downlink data transmission to the user equipment on a smaller number of HARQ processes.

[0120] In a ninth aspect, a non-transitory computer-readable medium is provided, comprising program instructions for causing an apparatus to at least perform the method according to the third or fourth aspect.

[0121] In the above, many different embodiments have been described. It should be appreciated that further embodiments may be provided by combining any two or more of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0122] Embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0123] Figure 1 A schematic diagram of an example 5GS communication system is shown;

[0124] Figure 2 A schematic diagram of an example mobile communication device is shown;

[0125] Figure 3 A schematic diagram of an example control device is shown;

[0126] Figure 4 A flow chart showing a method according to an example embodiment is shown;

[0127] Figure 5 A flow chart showing a method according to an example embodiment is shown;

[0128] Figure 6 shows a signaling flow diagram between a UE and a BS according to an example embodiment;

[0129] Figure 7 A flowchart of a method at a UE according to an example embodiment is shown;

[0130] Figure 8 shows a signaling flow diagram between a UE and a BS according to an example embodiment;

[0131] Fig. 9 A flow chart of a method at a UE according to an example embodiment is shown. DETAILED DESCRIPTION

[0132] Before explaining the examples in detail, refer to Figure 1 , Figure 2 and Figure 3 Certain general principles of wireless communication systems and mobile communication devices are briefly explained to aid understanding of the technology behind the described examples.

[0133] An example of a suitable communication system is the 5G or NR concept. The network architecture in NR may be similar to that of advanced LTE. The base station of the NR system may be referred to as the next generation Node B (gNB). Changes to the network architecture may depend on the need to support various radio technologies and more sophisticated quality of service (QoS) support, as well as some on-demand requirements for QoS levels such as supporting user quality of experience (QoE). In addition, network-aware services and applications, as well as service and application-aware networks, may bring changes to the architecture. Those involve information-centric networks (ICNs) and user-centric content distribution networks (UC-CDN) approaches. NR may use multiple-input-multiple-output (MIMO) antennas, more base stations or nodes than LTE (the so-called small cell concept), including macro base stations that operate in collaborative operation with smaller base stations and may also employ various radio technologies for better coverage and enhanced data rates.

[0134] Future networks may utilize network function virtualization (NFV), which is a network architecture concept that proposes virtualizing network node functions into "building blocks" or entities that can be operably connected or linked together to provide services. Virtualized network functions (VNFs) may include one or more virtual machines that use standard or general-purpose servers rather than custom hardware to run computer program codes. Cloud computing or data storage may also be utilized. In radio communications, this may mean that node operations are at least partially performed in a server, host, or node that is operably coupled to a remote radio head. Node operations may also be distributed among multiple servers, nodes, or hosts. It should also be understood that the distribution of work between core network operations and base station operations may be different from that of LTE or even non-existent.

[0135] Figure 1 A schematic diagram of a 5G system (5GS) 100 is shown. The 5GS may include a user equipment (UE) 102 (which may also be referred to as a communication device or terminal), a 5G radio access network (5GRAN) 104, a 5G core network (5GCN) 106, one or more internal or external application functions (AFs) 108, and one or more data networks (DNs) 110.

[0136] An example 5G core network (CN) includes functional entities. The 5G CN 106 may include one or more access and mobility management functions (AMFs) 112, one or more session management functions (SMFs) 114, an authentication server function (AUSF) 116, a unified data management (UDM) 118, one or more user plane functions (UPFs) 120, a unified data repository (UDR) 122, and / or a network exposure function (NEF) 124. The UPF is controlled by the SMF (session management function), which receives policies from the PCF (policy control function).

[0137] The CN is connected to the UE via the RAN. The 5G RAN may include one or more gNodeB (gNB) distributed unit (DU) functions connected to one or more gNodeB (gNB) centralized unit (CU) functions. The RAN may include one or more access nodes.

[0138] A user plane function (UPF) called a PDU Session Anchor (PSA) may be responsible for forwarding frames back and forth between the DN and the tunnel established over 5G to the UE exchanging traffic with the DN.

[0139] Now refer to Figure 2 describing in more detail possible mobile communication devices, Figure 2 A schematic partial cutaway view of a communication device 200 is shown. Such a communication device is generally referred to as a user equipment (UE) or a terminal. Suitable mobile communication devices can be provided by any device capable of sending and receiving radio signals. Non-limiting examples include a mobile station (MS) or a mobile device such as a mobile phone or a so-called smart phone, a computer with a wireless interface card or other wireless interface facilities (e.g., a USB dongle), a personal data assistant (PDA) or a tablet computer with wireless communication capabilities, a voice over IP (VoIP) phone, a portable computer, a desktop computer, an image capture terminal device such as a digital camera, a game terminal device, a music storage and playback device, a vehicle-mounted wireless terminal device, a wireless endpoint, a mobile station, a laptop embedded device (LEE), a laptop device (LME), an intelligent device, a wireless customer premises equipment (CPE) or any combination of these, etc. A mobile communication device can provide, for example, a communication for carrying data for communication, such as voice, email (email), text message, multimedia, etc. Therefore, users can supply and provide many services via their communication devices. Non-limiting examples of these services include two-way or multi-way calls, data communications or multimedia services or simply access to a data communications network system such as the Internet. Users may also be provided with broadcast or multicast data. Non-limiting examples of content include downloads, television and radio programs, videos, advertisements, various alerts and other information.

[0140] The mobile device is typically provided with at least one data processing entity 201, at least one memory 202 and other possible components 203 in software and hardware for assisting in the execution of the tasks it is designed to perform, including control of access and communication to access systems and other communication devices. Data processing, storage and other related components can be provided on appropriate circuit boards and / or chipsets. This feature is represented by reference numeral 204. The user can control the operation of the mobile device through a suitable user interface such as a keyboard 205, voice commands, a touch-sensitive screen or tablet, a combination thereof, etc. A display 208, a speaker and a microphone may also be provided. In addition, the mobile communication device may include appropriate connectors (wired or wireless) to other devices and / or for connecting external accessories (e.g., hands-free devices).

[0141] The mobile device 200 may receive signals over the air interface or radio interface 207 via appropriate means for receiving, and may transmit signals via appropriate means for transmitting radio signals. Figure 2 In the embodiment of the present invention, the transceiver arrangement is schematically designated by the block 206. The transceiver arrangement 206 may be provided, for example, by means of a radio part and an associated antenna arrangement. The antenna arrangement may be arranged internally or externally to the mobile device.

[0142] Figure 3 An example of a control device 300 for a communication system is shown, for example, coupled to and / or used to control a station of an access system, such as a RAN node, for example, a base station, an eNB or a gNB, a relay node or a core network node, such as an MME or a serving gateway (S-GW) or a packet data network gateway (P-GW), or a core network function, such as an AMF / SMF, or a server or a host. The method can be implemented in a single control device or on more than one control device. The control device can be integrated with a node or module of the core network or RAN or external to it. In some embodiments, the base station includes a separate control device unit or module. In other embodiments, the control device can be other network elements such as a radio network controller or a spectrum controller. In some embodiments, each base station can have such a control device as well as a control device provided in a radio network controller. The control device 300 can be arranged to provide control of communications in a service area of ​​the system. The control device 300 includes at least one memory 301, at least one data processing unit 302, 303 and an input / output interface 304. Via the interface, the control device can be coupled to a receiver and a transmitter of the base station. The receiver and / or the transmitter may be implemented as a radio front end or a remote radio head.

[0143] Cellular radio communication systems support several different mechanisms for error handling on the radio interface between a base station (BS) (e.g., gNB) and a terminal (e.g., UE) of the network to reduce data loss over the air interface.

[0144] Some higher layer error recovery mechanisms such as TCP (Transmission Control Protocol) retransmission or RLC (Radio Link Control) retransmission may cause high delay and overhead. Systems such as 3G, 4G and 5G also support L1 / physical layer retransmission using HARQ (Hybrid Automatic Repeat Request).

[0145] HARQ operations in 4G / LTE and 5G / NR are based on operations in terms of addressable HARQ processes. For PDSCH operations, the BS knows successful reception (ie, "ACK") or unsuccessful reception (ie, "NACK") based on HARQ-ACK feedback from the UE to the BS.

[0146] When a "NACK" is received for a certain HARQ process, the BS can schedule a retransmission to the UE of the transport block associated with the HARQ process. The same situation can occur when the BS fails to receive a "NACK" or "ACK", which indicates that the UE failed to receive the DL resource allocation grant for the scheduled HARQ process (which means that the UE did not even send a "NACK" or "ACK"), or the BS failed to receive the HARQ-ACK feedback (i.e., "ACK" or "NACK" is interpreted as "DTX" (discontinuous transmission), i.e., "no transmission")). In order to be able to combine the received data of an earlier transmission attempt and a later retransmission, the UE stores the soft buffer data of the transport block in its soft buffer memory so that the initial (i.e., first) transmission and potential retransmissions can be combined to improve the detection reliability of the BS for all transmission attempts.

[0147] Currently two different combining mechanisms are defined. The first is chase combining (CC), where all transmissions (e.g., original transmission and retransmissions) use the same coded data of a transport block, while the second is incremental redundancy (IR), where different parts of the coded data are transmitted in a transmission attempt, allowing for increased coding redundancy of the underlying shared channel (SCH) channel codec, which may lead to further improved PDSCH detection reliability.

[0148] 4G and 5G support HARQ for shared channel (SCH) operation in UL and DL, i.e., for PUSCH and PDSCH. There is an inherent assumption in the system design and operation that the UE has enough soft buffer memory to achieve full capability in terms of DL data rate & HARQ processes to support DL HARQ soft combining (soft buffer memory is required).

[0149] Currently, if the UE is indicated a new initial PDSCH transmission for a HARQ process through dynamic scheduling based on the switched NDI (New Data Indicator field) in the DCI, the UE will clear the soft buffer of the HARQ process. When a new semi-persistent scheduling grant for the same HARQ process is available, the UE clears the soft buffer for the SPS PDSCH.

[0150] The HARQ retransmission operation can be efficient because UE combining BS transmission attempts improves reliability and reduces required radio resources (in terms of transmission power, radio resource consumption, etc.) compared to retransmission without L1 layer combining of received signals without initial transmission and retransmission.

[0151] On the other hand, as the data rate supported by the UE continues to increase and the number of HARQ processes increases, the demand for the soft buffer memory increases to store the soft buffer values ​​for PDSCH reception.

[0152] The UE is only rarely scheduled at a data rate that requires a full soft buffer memory. Most of the time only a portion of the soft buffer memory is used. Such very fast memory suitable for the soft buffer memory can be expensive, so for 6G an attempt is made to operate the UE with less soft buffer memory to keep the 6G technology cost reasonable compared to current 4G / 5G.

[0153] The expensive soft buffer memory of the UE does not need to be sized according to the peak throughput supported by the UE, because most of the time the expensive memory will be only partially utilized. However, when the UE does not have enough soft buffers for all HARQ processes, the decoding performance for retransmissions is degraded. This leads to non-optimal link adaptation and performance when the BS is unaware of how the UE manages the soft buffer shortage with respect to the HARQ processes.

[0154] Removing L1 HARQ retransmissions from 6G systems will eliminate the need for soft buffer memory in the UE. However, this will occur at the expense of reduced DL system performance, as the DL HARQ combining gain in the case of operating only with L1ARQ (i.e., PDSCH retransmissions without signal combining of received transmission attempts) will be lost.

[0155] Figure 4 A flow chart of a method according to an example embodiment is shown.

[0156] In 401, the method comprises receiving at a user equipment at least one downlink data transmission from a network node.

[0157] In 402, the method includes determining that decoding of at least one downlink data transmission at a user equipment is unsuccessful.

[0158] In 403, the method includes determining soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and based at least in part on the downlink data transmission.

[0159] In 404, the method includes providing soft buffer information from the user equipment to the network node.

[0160] In 405, the method includes receiving a schedule for another downlink data transmission, wherein the schedule for the another downlink data transmission depends on the provided soft buffer information.

[0161] Figure 5 A flow chart of a method according to an example embodiment is shown.

[0162] In 501, the method comprises providing at least one downlink data transmission from a network node to a user equipment.

[0163] In 502, the method includes receiving, at a network node, from a user equipment, soft buffer information determined based on at least one downlink data transmission.

[0164] In 503, the method includes determining another downlink data transmission schedule based on the received soft buffer information.

[0165] At least one DL transmission may be sent via the PDSCH.The at least one DL transmission may include one or more spatial layers, one or more transport blocks, and / or one or more HARQ processes sent during one or more time slots.

[0166] Determining that decoding of at least one downlink data transmission at the user equipment was unsuccessful may be based on, for example, cyclic redundancy bits (using, for example, a cyclic redundancy check (CRC)), or any other suitable method of identifying reliability of a data transmission.

[0167] Receiving a schedule for another downlink data transmission may include, for example, PDCCH monitoring (also known as blind detection), reading downlink control information DCI from the detected PDCCH, and operating according to the received DCI. The DCI may include PDSCH resource information (e.g., which PRB and OFDM symbol of the UE does not map data). The DCI may also include modulation and coding (MCS) related information and / or HARQ related information, such as HARQ process ID, RV and / or NDI.

[0168] The method may provide a mechanism to manage soft buffer usage for UEs with limited soft buffer memory.An alternative solution for managing soft buffer usage shortage is proposed as follows.

[0169] As reference Figure 4The described method may include receiving, at a user equipment, a configuration from a network node to provide soft buffer information. The configuration may be received using RRC signaling or MAC CE. The configuration may include configuration of soft buffer information reporting or activation or deactivation of soft buffer information reporting.

[0170] The configuration may be provided from the network node to the user equipment in response to an indication of the user equipment soft buffer information reporting capability from the user equipment to the network node.

[0171] Determining the scheduling of another downlink transmission may include at least one of the following: providing an indication to the user equipment that soft bits for another downlink data transmission should not be stored; configuring the user equipment to use a smaller number of HARQ processes; modifying scheduling parameters; or scheduling downlink data transmission to the user equipment in a smaller number of HARQ processes (for example, the BS may schedule an indication of retransmission of a HARQ process / PDSCH for which soft buffer bits are not stored).

[0172] In an example embodiment, based on the indication provided by the UE, for a (group of) HARQ processes, the UE does not expect retransmissions with any other RV than RV0, which indicates that the soft buffer bits have not been stored. Similarly, the BS in its potential retransmission decisions will take this information into account and will not schedule retransmissions of HARQ processes with any other RV than RV0, which processes (part of the HARQ process group) are indicated as not stored soft buffer bits. This is an example of determining another downlink data transmission scheduling based on the received soft buffer information. The retransmission may include only a code block or part of a code block group of the PDSCH.

[0173] The soft buffer information may include an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment. Each of the at least one data transmission is associated with a given hybrid automatic repeat request HARQ process such that the soft buffer information is associated with the given HARQ process.

[0174] In a first example embodiment, the UE indicates (eg, as part of a HARQ-ACK feedback) that the soft bits of the HARQ process concerned have not been stored (or have been stored) in the UE soft buffer memory.

[0175] For example, if the soft buffer memory of the UE is insufficient, the UE selects some PDSCHs whose soft bits are not stored. The UE can decide whether to store the soft bits of the decoded PDSCH from the HARQ process in its soft buffer memory and indicate to the BS whether the soft bits of the HARQ process will be used for potential retransmission soft combining. This is an example of an indication of whether the soft bits of the downlink data transmission are stored in the soft buffer memory of the user equipment.

[0176] In the example embodiment, the implicit assumption is that the UE stores soft bits in case of unsuccessful reception (i.e., the UE will indicate NACK) and will not store soft bits in case of successful reception (i.e., the UE will indicate ACK). Therefore, the reporting of 'ACK' will implicitly indicate that soft bits are not stored and 'NACK' indicates that soft bits are stored. When soft bits are not stored, the UE may also flush the soft buffer of the corresponding HARQ process without waiting for NDI.

[0177] For this alternative, no additional signaling overhead is required for HARQ feedback besides ACK / NACK reporting.

[0178] An indication of whether the soft bits for the downlink data transmission are stored in the soft buffer memory of the user equipment may be provided by HARQ feedback.

[0179] In an example embodiment, as part of the HARQ-ACK feedback report, the UE indicates whether to store soft bits in the soft buffer memory for that HARQ process in addition to 'ACK' or 'NACK'.

[0180] This indication may be provided as a separate bit from the HARQ feedback.

[0181] For example, in addition to the (multiple) HARQ-ACK bits for the HARQ process, there may also be a separate bit for the HARQ process for which the HARQ-ACK is to be reported, which indicates by a state of '0' (or '1') that the soft bits for the HARQ process are stored by the UE or by a state of '1' (or '0') that the soft buffer bits for the HARQ-ACK process have not yet been stored. For this case, N+1 bits are required for HARQ-ACK feedback instead of N bits of HARQ-ACK for traditional HARQ-ACK reports. For this example embodiment, the HARQ-ACK bits of the HARQ process are appended with an additional bit to indicate that the soft bits of the HARQ process are stored. N bits can be used to provide HARQ-ACK for multiple transport block code blocks or code block groups for downlink transmissions. This information can provide decoding reliability information, for example, based on a decoded log-likelihood ratio rather than simple ACK / NACK information.

[0182] The HARQ-ACK feedback codebook construction may be based on each HARQ process or each PDSCH, but instead of N bits, N+1 bits will be mapped for a certain HARQ-ACK process (or PDSCH).

[0183] The indication may be jointly encoded with the HARQ feedback. In an example embodiment, the UE's 'ACK / NACK' information together with the indication on the soft buffer memory are jointly encoded using M bits for the HARQ process (or PDSCH).

[0184] Some states of the joint indication will be associated with stored soft bits and some indication states will be associated with non-stored soft bits.

[0185] The association with the status may be defined in the specification (hard coded) or defined by higher layer signaling (such as MAC CE or RRC).

[0186] For a correctly received PDSCH there may be an implicit association that the UE will not store soft bits, and for a reported 'ACK' the BS automatically assumes that no soft bits are stored.

[0187] This may allow for smaller size information per HARQ process, or combined with additional enhanced HARQ-ACK feedback information such as related to detection reliability.

[0188] The HARQ-ACK feedback codebook construction may be done based on the HARQ process or the received PDSCH or PDSCH opportunity, but instead of N bits for the HARQ-ACK process (or PDSCH), M bits will be mapped for a certain HARQ-ACK process.

[0189] As an example, for a scheduled HARQ process with two transport blocks (resulting in N=2), for example, M=2 bits may be used to indicate 4 states, including:

[0190] {ACK, ACK}, 'The soft bits are not stored.

[0191] {NACK, ACK}, 'The soft bits are not stored.

[0192] {ACK, NACK}, 'The soft bits are not stored.

[0193] {NACK, NACK}, 'Soft bits are stored'

[0194] In another example embodiment, the indication is appended to the HARQ-ACK codebook (and jointly encoded).

[0195] The additional information stored in the soft bits may be based on a bitmap of size K, where each bit is mapped to a HARQ process (or PDSCH) or a group / set of HARQ processes (or PDSCH) for which HARQ-ACK is provided in the codebook (one-to-one mapping with the HARQ-ACK position in the codebook). Alternatively, a bitmap of size L may cover all HARQ processes configured for UEs in one DL serving cell or all DL serving cells.

[0196] If a bit is mapped to more than one HARQ-ACK process or PDSCH (e.g., to a HARQ process or PDSCH group / set), the soft bit is stored for the HARQ-ACK process based on a '0' (or '1') being associated with the soft bit, and a '1' (or '0') being associated with the soft bit of the HARQ process or PDSCH and not being stored, so that a logical "AND" or "OR" operation can be used between individual HARQ processes / PDSCHs within the group.

[0197] The HARQ-ACK process or PDSCH grouping to K additional bits may be defined in the specification or by higher layer signaling (such as MAC CE or RRC).

[0198] Alternatively or additionally, the indication may be provided as part of the UCI.

[0199] In an example embodiment, the UE's indication to the BS is reported on the PUCCH or PUSCH as uplink control information (UCI) independent of the HARQ-ACK reporting.

[0200] There may be a bitmap of size K where there is a bit for each HARQ process (or PDSCH) or a bit for a group / set of HARQ processes (or PDSCH) where HARQ-ACK is also reported.

[0201] There may be logic and / or operations applied within more than one HARQ process (or PDSCH) group / set, and the definition of HARQ process (or PDSCH) groups / sets may be defined by specifications or higher layer signaling (such as RRC or MAC-CE).

[0202] Regardless of whether HARQ-ACK is provided, there may be a bitmap of size L for each HARQ process or HARQ process group / set for one DL serving cell or all DL serving cells.

[0203] The logic and / or operations may be applied within a group / set of more than one HARQ process, and the definition of the group / set of HARQ processes may be defined by specifications or higher layer signaling (such as RRC or MAC-CE).

[0204] The method may include determining whether to store soft bits for a downlink HARQ process based on at least one of: a priority associated with the downlink data transmission, whether the downlink data transmission was successfully decoded, or an available capacity of a soft buffer memory.

[0205] The decision to store or not store soft bits in its soft buffer memory may be UE implementation specific. The soft bit storage decision may be based on, for example, an MCS threshold or a transport block size threshold (e.g., because a smaller MCS may be decoded more reliably, soft bit storage may not be required). However, the UE may be restricted, for example by specification or configuration, to decide to store / not store soft bits only in lower priority PDSCHs, and high priority PDSCHs are received correctly (i.e., based on cyclic redundancy bits, cyclic redundancy check (CRC) passes). In other words, soft bits of a high priority PDSCH with a failed CRC are always stored. The 'priority' of a PDSCH may be determined by at least one of the logical channel priority (LCP) of the HARQ-ACK associated with the PDSCH and the L1 layer / PHY priority.

[0206] This is an example of determining whether to store soft bits for a downlink HARQ process based on at least a priority level associated with downlink data transmission.

[0207] Since the PDSCH transport block associated with the HARQ process has been successfully received and the data has been delivered to higher layers (including HARQ-ACK "ACK" to MAC) even if a retransmission will be scheduled, the UE may not store the soft bits of the successfully received / decoded PDSCH HARQ process in its soft buffer memory. Alternatively, the UE may only store the hard bits for the successfully received PDSCH TBs (with minimal memory consumption). The UE may also choose not to store the successfully received code blocks or code block groups that form part of the PDSCH transport block. For this case, the assumption may be implicit that soft bits are not stored for 'ACK' and soft bits are stored for 'NACK', and the relevant signaling will be implicit here. This is an example of determining whether to store soft bits for a downlink HARQ process based at least on whether the downlink data transmission is successfully decoded.

[0208] If the UE is approaching the soft buffer limit and cannot correctly decode the PDSCH transport blocks of a HARQ process, depending on the priority of the PDSCH associated with the HARQ process, the UE may decide to store or not store the soft bits in its soft buffer memory.

[0209] The decision to store or not store soft bits for a particular priority PDSCH may also be influenced by the soft buffer memory still available. For example, if the soft buffer is empty, soft bits for lower priority PDSCHs may be stored, whereas as the soft buffer fills and becomes close to the limit, lower priority PDSCHs may be deemed not worth saving soft bits to still keep some soft buffer memory available for potential scheduling of high (higher) priority PDSCHs associated with the HARQ process.

[0210] If there is not enough soft buffer memory available to store the soft bits of the HARQ process, the UE may decide not to store the soft bits of the HARQ process in its soft buffer memory. This is an example of determining whether to store soft bits for a downlink HARQ process based at least on the available capacity of the soft buffer memory.

[0211] Figure 6 A flow chart between a UE and a BS for an example embodiment is shown, wherein the UE indicates that soft bits of a related HARQ process have not been stored in a soft buffer memory of the UE. This is an example, wherein the soft buffer information includes an indication of whether soft bits for a downlink data transmission are stored in a soft buffer memory of the user equipment.

[0212] In step 0, the BS sends high-level signaling to the UE regarding the UE soft buffer feedback report. The high-level signaling may be sent using RRC or MAC CE. The high-level signaling may include activation or configuration of the UE soft buffer feedback report. The signaling may include further information provided by the BS regarding the prioritization of soft buffer usage. This is an example of receiving a configuration from a network node at a user equipment to provide soft buffer information.

[0213] Activation / configuration may be done based on earlier UE signaling indicating its capability for soft buffer feedback reporting.This is an example of providing an indication of user equipment soft buffer information reporting capability from a user equipment to a network node and receiving at the user equipment a configuration from the network node to provide soft buffer information in response.

[0214] In step 1, the BS transmits a PDSCH to the UE. This is an example of providing at least one downlink data transmission from a network node to the user equipment.

[0215] In step 2, the UE receives and decodes the PDSCH. This is an example of receiving at least one downlink data transmission at the user equipment from the network node and determining that decoding of the at least one downlink data transmission at the user equipment was unsuccessful.

[0216] In step 3, the UE determines whether the PDSCH soft bits are to be stored. This is an example of determining soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and based at least in part on the downlink data transmission. The decision to store or not store soft bits in its soft buffer memory may be UE implementation specific. Alternatively or additionally, the UE may be restricted by specification or configuration to decide to store / not store soft bits only in lower priority PDSCHs (i.e., soft bits for high priority PDSCHs are always stored), as described above.

[0217] In step 4, the decision to store and not store (i.e., have or not have available) soft bits for the DL HARQ process is indicated by the UE to the BS. The indication may be transmitted jointly with the HARQ feedback or as a separate UCI transmission. This is an example of providing soft buffer information from the user equipment to the network node, wherein the soft buffer information includes an indication of whether the soft bits for the downlink data transmission are stored in the soft buffer memory of the user equipment.

[0218] In step 5, based on the indication provided by the UE and received by the BS in step 4, the BS is only allowed to apply RV0 to retransmissions of HARQ processes / PDSCHs for which no soft buffer bits have been stored. The BS applies this restriction when preparing for potential L1 retransmissions of the PDSCH. This is an example of determining another downlink data transmission schedule based on the received soft buffer information.

[0219] In step 6, the BS transmits the L1 retransmission of the DL HARQ process or PDSCH (transport block) to the UE.

[0220] In step 7, when the UE receives L1 retransmission of a DL HARQ process or PDSCH (transport block), if it is indicated in step 4 that soft bits are not saved for PDSCH, the UE only expects RV0, and the UE will not perform soft combining on the soft bits of multiple (re) transmissions. Otherwise, the UE receives PDSCH and can apply soft combining on the soft bits of multiple (re) transmissions.

[0221] Figure 7 A flow chart of an example method from a UE perspective is shown.

[0222] In 700, the UE receives high-level signaling of UE soft buffer configuration from the BS. The signaling may be performed via RRC or MAC CE. The signaling may inform the UE to enable UE soft buffer indication. The signaling may contain further information from the BS regarding prioritization of soft buffer usage.

[0223] In 701 , a UE receives an initial (ie, first) PDSCH transmission and decodes the PDSCH.

[0224] In 702, the UE determines whether PDSCH soft bits are stored.

[0225] In 703, the UE indicates to the BS whether the PDSCH soft bits are stored (or not stored) based on the determination in step 702. The indication may be transmitted jointly with the HARQ feedback or as a separate UCI transmission.

[0226] In 704, the UE receives the PDSCH retransmission.

[0227] In 705, the UE determines whether, for the received PDSCH retransmission of step 704, the soft bits of the initial PDSCH transmission have been indicated as not saved as determined in step 702 ('Yes'), or not indicated as not saved ('No').

[0228] If 'yes', the UE proceeds to step 706 .

[0229] In 706, the UE may only expect PDSCH retransmissions to be scheduled with redundancy version RV0.

[0230] In 707, the UE decodes the PDSCH retransmission without soft bit combining the multiple (re)transmitted soft bits.

[0231] If 'No', the UE proceeds to step 708 .

[0232] At 708, the UE may expect PDSCH retransmissions to be scheduled with any supported HARQ retransmission redundancy version.

[0233] In 709, the UE decodes the PDSCH retransmission and may apply soft bit combining to the multiple (re)transmitted soft bits.

[0234] The soft buffer information may include an indication of available soft buffer capacity.

[0235] In an example embodiment, the UE indicates to the BS the current status of its available (or used) soft buffer memory, and the BS takes this information into account in its scheduling decisions.

[0236] P bits may be appended to the HARQ-ACK feedback to indicate the soft buffer status. The combined HARQ-ACK feedback (i.e., consisting of S bits for the HARQ-ACK codebook and the additional P bits for the soft buffer status indication) is jointly encoded and then fed back to the BS as part of the HARQ-ACK feedback operation on the PUCCH or PUSCH.

[0237] The soft buffer information may include an indication of available soft buffer capacity compared to at least one threshold capacity value.

[0238] For example, the UE may indicate with '0' that the current soft buffer usage is below the soft buffer threshold and with '1' that the soft buffer usage is above a certain threshold. The threshold may be fixed in the specification or may be defined by higher layer signaling such as MAC CE or RRC.

[0239] The threshold may be defined according to a share or percentage of the total available soft buffer memory of the UE, or may be defined by the share of HARQ processes occupying the soft buffer memory.

[0240] More than one threshold may be defined to provide higher granularity reporting, for example Q bits allows 2^Q-1 thresholds to be defined. For a single threshold, Q will be equal to 1.

[0241] The indication of the threshold may be considered overall from the UE perspective or may also be for each DL serving cell configured and / or activated for DL ​​carrier aggregation.

[0242] For the indication per UE, P = Q. For the indication per serving cell, P will be equal to P = Q * R, where R is the number of serving cells configured and / or activated for DL ​​carrier aggregation. If the threshold number is defined per serving cell or the indication operates per serving cell (i.e., whether there is an indication or not), then typically the number of bits required will be

[0243] The indication of available soft buffer capacity may be provided in HARQ feedback, periodic uplink control information, aperiodic uplink control information, or a medium access control control element.

[0244] For example, the indication of the soft buffer status may be fed back by the UE as part of the uplink control information (UCI) with P bits as described above. The report will not be tied to the HARQ-ACK feedback, but may be a new type of UCI utilizing the associated UL resources. The related reports may be periodic or aperiodic based on higher layer signaling (such as RRC or MAC CE), possibly using L1 signaling activation procedures (similar to the CSI reporting framework).

[0245] In another example embodiment, the signaling is carried from the UE to the gNB via a MAC CE. Table 1 shows an example of such a MAC CE. In this example embodiment, the soft buffer status (SBS) is transmitted via a 4-bit SBS field. The soft buffer status may have a dedicated LCID (Logical Channel Identifier) ​​for the UL-SCH (Uplink Shared Channel). Table 1

[0246] Based on the provided information, the BS may take the UE's soft buffer status into account in its further operations.In an example embodiment, the BS may decide not to schedule new transmissions to the UE on HARQ processes on previously unused HARQ processes, but may schedule new data transmissions only on HARQ processes with soft buffer bits.

[0247] In another example embodiment, the BS may indicate to the UE for a PDSCH transmission that soft bits for the PDSCH should not be stored. The BS may also apply different link adaptation (in transmit power or MCS setting) for PDSCH transmissions where soft bits are not stored and PDSCH transmissions where soft bits are stored.

[0248] Figure 8 A signaling flow between a UE and a BS for an example embodiment is shown, where the UE indicates to the BS the current status of its soft buffer memory availability to be taken into account by the BS in its further PDSCH operations for the UE. This is an example where the soft buffer information includes an indication of the available soft buffer capacity.

[0249] In step 0, the BS sends high-layer signaling to the UE regarding the UE soft buffer status report. The high-layer signaling may be sent using RRC or MAC CE. The high-layer signaling may contain activation or configuration of the UE soft buffer status report and related operating parameters, such as a reporting threshold. The threshold may be defined based on a share or percentage of the available soft buffer memory, or may be defined by a share of the HARQ process occupying the soft buffer memory. The threshold may be defined per UE (overall) or per DL serving cell. The activation / configuration may be done based on earlier UE signaling indicating its capability for soft buffer reporting.

[0250] In step 1, the BS transmits a PDSCH to the UE.

[0251] In step 2, the UE receives and decodes the PDSCH.

[0252] In step 3, the UE determines its current soft buffer status after decoding the relevant PDSCH. This is an example of determining the soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and based at least in part on the downlink data transmission.

[0253] In step 4, the UE feeds back information about its soft buffer usage based on the determination of step 3. An indication of the soft buffer status in the UE may be appended by the UE to the HARQ-ACK codebook feedback, that is, P bits may be appended to the HARQ-ACK to indicate the soft buffer status. The combined HARQ-ACK feedback (i.e., consisting of S bits for the HARQ-ACK codebook and an additional P bits for the soft buffer status indication) is part of the feedback operation on the PUCCH or PUSCH in step 4. Alternatively, the P bits may be transmitted as periodic or aperiodic uplink control information feedback or as signaling from the UE to be carried by a MAC CE. This is an example of providing soft buffer information from a user equipment to a network node, wherein the soft buffer information includes an indication of the available soft buffer capacity.

[0254] In step 5, based on the information provided by the UE in step 4, the BS may consider the soft buffer status of the UE in further operations by determining whether the UE needs to store more soft buffer bits.

[0255] For example, the BS may decide not to schedule new transmissions to the UE on HARQ processes that were previously unused, but may schedule new data transmissions only on HARQ processes that have soft buffer bits.

[0256] In another example, the BS may indicate to the UE for a PDSCH transmission that the soft buffer bits for the PDSCH should not be stored.

[0257] In step 6 , the BS transmits the PDSCH to the UE based on the BS consideration and / or the determination of step 5 .

[0258] Fig. 9 A flow chart showing the operation from the UE perspective is shown.

[0259] In 900, the UE receives signaling regarding the UE soft buffer configuration. The signaling may be performed by higher layer signaling such as RRC or MAC CE. The signaling may include activation of the UE soft buffer status report and related operating parameters such as a reporting threshold. The threshold may be defined based on a share or percentage of available soft buffer memory, or may be defined by a share of HARQ processes occupying the soft buffer memory. The threshold may be defined per UE (overall) or per DL serving cell.

[0260] In 901, the UE receives and decodes the PDSCH.

[0261] In 902, the UE determines its current soft buffer usage / status after decoding of the relevant PDSCH.

[0262] In 903, the UE indicates its soft buffer usage / status to the BS based on the determination of step 902. The indication of the soft buffer status in the UE can be attached by the UE to the HARQ-ACK codebook feedback, that is, P bits can be attached to the HARQ-ACK to indicate the soft buffer status. The combined HARQ-ACK feedback (i.e., consisting of S bits for the HARQ-ACK codebook and the additional P bits for the soft buffer status indication) is part of the feedback operation on the PUCCH or PUSCH in step 4. Alternatively, the P bits can be transmitted as periodic or aperiodic uplink control information feedback or as signaling from the UE to be carried by the MAC CE.

[0263] Note that there may also be combinations of different examples, eg where the UE reports its current soft buffer status and the HARQ processes that have (or have not) stored soft bits.

[0264] Alternatively, the UE shall only report the soft buffer status, but when the UE reports the soft buffer status above a certain threshold, the UE shall not store soft bits for any PDSCH or for any PDSCH with lower priority or for a preconfigured portion of the HARQ processes.

[0265] This approach can provide good link adaptation and performance while relaxing the amount of expensive soft buffer memory the UE is required to have and allowing the UE to face situations with soft buffer shortage.

[0266] An apparatus may include: a component for receiving at least one downlink data transmission from a network node at a user equipment; a component for determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful; a component for determining soft buffer information based on determining that decoding of at least one downlink data transmission at the user equipment is unsuccessful and at least partially based on the downlink data transmission; a component for providing soft buffer information from the user equipment to the network node; and a component for receiving scheduling for another downlink data transmission, wherein the scheduling for the another downlink data transmission depends on the provided soft buffer information.

[0267] The apparatus may include a user equipment, such as a mobile phone, as the user equipment, or included in the user equipment or a chipset, for performing at least some actions of or for the user equipment.

[0268] Alternatively or additionally, an apparatus may include: a component for providing at least one downlink data transmission from a network node to a user equipment; a component for receiving soft buffer information determined based on at least one downlink data transmission from the user equipment at the network node; and a component for determining another downlink data transmission scheduling based on the received soft buffer information.

[0269] The apparatus may include a network node, such as a gNB, as the network node, or included in a network node or a chipset, for performing at least some actions of or for the network node.

[0270] It should be understood that the device may include or be coupled to other units or modules in or for transmission and / or reception, such as a radio component or a radio head. Although the device has been described as one entity, the different modules and memories may be implemented in one or more physical or logical entities.

[0271] Note that even though some embodiments have been described with respect to 5G networks, similar principles may apply with respect to other networks and communication systems, such as 6G networks or 5G-Advanced networks. Thus, although certain embodiments are described above by way of examples with reference to certain example architectures for wireless networks, technologies, and standards, the embodiments may be applied to any other suitable form of communication system than those illustrated and described herein.

[0272] It is also noted herein that while the above describes exemplifying embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention.

[0273] As used herein, “at least one of: ” and “at least one of ” and similar expressions, where a list of two or more elements is connected by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all of the elements.

[0274] In general, various embodiments may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects of the present disclosure may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by a controller, microprocessor, or other computing device, but the present disclosure is not limited thereto. Although various aspects of the present disclosure may be illustrated and described as block diagrams, flow charts, or using some other graphical representation, it should be understood that the boxes, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general hardware or controllers or other computing devices, or some combination thereof as non-limiting examples.

[0275] As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) hardware circuit implementation only (such as implementation in analog and / or digital circuits only) and (b) a combination of hardware circuitry and software, such as (where applicable): (i) A combination of analog and / or digital hardware circuits with software / firmware (ii) any portion of a hardware processor with software (including a digital signal processor), and the software and memory that work together to enable a device such as a mobile phone or server to perform various functions, and (iii) one or more hardware circuits and / or one or more processors, such as a microprocessor or portion of a microprocessor, that requires software (e.g., firmware) for operation, but the software may not be present when the software is not needed for operation.

[0276] This definition of circuitry applies to all uses of the item in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of only a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its accompanying software and / or firmware. For example, if applicable to the particular claim element, the term circuitry also covers a baseband integrated circuit or processor integrated circuit used in a mobile device or similar integrated circuit in a server, cellular network device, or other computing or network device.

[0277] Embodiments of the present disclosure may be implemented by computer software executable by a data processor of a mobile device, such as in a processor entity, or by hardware, or by a combination of software and hardware. Computer software or programs, also referred to as program products (including software routines, applets and / or macros), may be stored in any device-readable data storage medium, and they include program instructions for performing specific tasks. A computer program product may include one or more computer executable components that are configured to implement an embodiment when the program is running. One or more computer executable components may be at least one software code or part thereof.

[0278] In addition, in this regard, it should be noted that any box of the logic flow in the accompanying drawings can represent program steps, or interconnected logic circuits, boxes and functions, or a combination of program steps and logic circuits, boxes and functions. Software can be stored on such physical media as memory chips or memory blocks implemented in processors, magnetic media (such as hard disks or floppy disks) and optical media (such as, for example, DVDs and their data variants CDs). The physical media is a non-transitory medium. As used herein, the term "non-transitory" is a limitation of the medium itself (i.e., tangible rather than signals), rather than a limitation on data storage persistence (e.g., RAM vs. ROM).

[0279] The memory may be of any type suitable for the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. As non-limiting examples, the data processor may be of any type suitable for the local technical environment and may include one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an FPGA, a gate-level circuit, and a processor based on a multi-core processor architecture.

[0280] Embodiments of the present disclosure may be practiced in various components such as integrated circuit modules. The design of integrated circuits is essentially a highly automated process. Complex and powerful software tools are available to convert logic level designs into semiconductor circuit designs that are ready to be etched and formed on semiconductor substrates.

[0281] The scope of protection sought for various embodiments of the present disclosure is set out by the independent claims. The embodiments and features described in this specification shall be interpreted as examples useful for understanding various embodiments of the present disclosure if they do not fall within the scope of the independent claims.

[0282] The above description provides a complete and informative description of exemplary embodiments of the present disclosure by way of non-limiting examples. However, in view of the foregoing description, various modifications and adaptations may become apparent to those skilled in the relevant art when read in conjunction with the accompanying drawings and the appended claims. However, all of these and similar modifications of the teachings of the present disclosure will still fall within the scope of the present invention as defined in the appended claims. In fact, further embodiments include combinations of one or more embodiments with any other embodiments previously discussed.

Claims

1. A device for communication, comprising: means for receiving at least one downlink data transmission from a network node at a user equipment; means for determining that decoding of the at least one downlink data transmission at the user equipment was unsuccessful; means for determining soft buffer information based on determining that decoding of the at least one downlink data transmission at the user equipment was unsuccessful and based at least in part on the downlink data transmission; means for providing the soft buffer information from the user equipment to the network node; as well as Means for receiving a schedule for another downlink data transmission, wherein the schedule for the another downlink data transmission is dependent on the provided soft buffer information.

2. The apparatus of claim 1, wherein the soft buffer information comprises an indication of whether soft bits of the downlink data transmission are stored in a soft buffer memory of the user equipment.

3. An apparatus according to claim 1 or claim 2, wherein each of the at least one data transmission is associated with a given hybrid automatic repeat request (HARQ) process.

4. The apparatus of claim 2 or claim 3, wherein the indication is provided using HARQ feedback or uplink control information.

5. The device according to any one of claims 1 to 3, comprising: Means for determining whether to store soft bits for the downlink HARQ process based on at least one of: a priority associated with the downlink data transmission, whether the downlink data transmission was successfully decoded, or an available capacity of the soft buffer memory.

6. An apparatus according to any one of claims 1 to 3, wherein the soft buffer information comprises an indication of available soft buffer capacity.

7. The apparatus of claim 6, wherein the soft buffer information comprises an indication of available soft buffer capacity relative to at least one threshold capacity.

8. The apparatus according to any one of claims 1 to 3, comprising means for receiving, at the user equipment, from the network node a configuration to provide the soft buffer information.

9. The apparatus of claim 8, wherein the configuration comprises configuration of soft buffer information reporting or activation of soft buffer information reporting.

10. The apparatus of claim 8, comprising a component for providing an indication of a user equipment soft buffer information reporting capability from the user equipment to the network node; and a component for receiving, at the user equipment, a configuration from the network node to provide the soft buffer information in response.

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