WO2023000275A1

WO2023000275A1 - Method, device and computer readable medium for communication

Info

Publication number: WO2023000275A1
Application number: PCT/CN2021/107964
Authority: WO
Inventors: Da Wang; Lin Liang; Gang Wang
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2021-07-22
Filing date: 2021-07-22
Publication date: 2023-01-26
Anticipated expiration: 2024-01-22

Abstract

The present invention discloses methods, devices and computer readable media for communication. According to embodiments of the present invention, a terminal device receives, from a network device, a configuration for survival time. The terminal device monitors an unsuccessful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration. If a condition for triggering the survival time is satisfied, the terminal device transmits the data packet with packet data convergence protocol (PDCP) duplication or change a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity. In this way, the transmission reliability can be improved and the latency of transmissions can be reduced.

Description

METHOD, DEVICE AND COMPUTER READABLE MEDIUM FOR COMMUNICATION

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to methods, devices and computer storage media for communication.

BACKGROUND

With development of communication technologies, several solutions have been proposed to provide efficient and reliable solutions for communication. For example, duplication of transmissions has been proposed. When duplication is configured for a radio bearer by radio resource control (RRC) , at least one secondary radio link control (RLC) entity is added to a radio bearer to handle the duplicated packet data convergence protocol (PDCP) protocol data units (PDUs) , where the logical channel corresponding to the primary RLC entity is referred to as the primary logical channel, and the logical channel corresponding to the secondary RLC entity (ies) , the secondary logical channel (s) . All RLC entities have the same RLC mode. Duplication at PDCP therefore consists in submitting the same PDCP PDUs multiple times: once to each activated RLC entity for the radio bearer. With multiple independent transmission paths, packet duplication therefore increases reliability and reduces latency and is especially beneficial for URLLC services. When configuring duplication for a data radio bearer (DRB) , RRC also sets the state of PDCP duplication (either activated or deactivated) at the time of (re-) configuration. After the configuration, the PDCP duplication state can then be dynamically controlled by means of a medium access control (MAC) control element.

SUMMARY

In general, embodiments of the present disclosure provide methods, devices and computer storage media for communications.

In a first aspect, there is provided a method of communication. The method comprises: receiving, at a terminal device and from a network device, a configuration for survival time; monitoring an unsuccessful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and in accordance with a determination that a condition for triggering the survival time is satisfied, performing at least one of: transmitting the data packet with packet data convergence protocol (PDCP) duplication; or changing a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity.

In a second aspect, there is provided a method of communication. The method comprises: receiving, at a terminal device and from a network device, a configuration for survival time; in accordance with a determination that the survival time is triggered, monitoring a successful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and in accordance with a determination that a condition for leaving the survival time is satisfied, performing at least one of: transmitting the data packet without packet data convergence protocol (PDCP) duplication; or changing a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity.

In a third aspect, there is provided a terminal device. The terminal device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the terminal device to perform: receiving, from a network device, a configuration for survival time; monitoring an unsuccessful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and in accordance with a determination that a condition for triggering the survival time is satisfied, performing at least one of: transmitting the data packet with packet data convergence protocol (PDCP) duplication; or changing a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity.

In a fourth aspect, there is provided a terminal device. The terminal device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the terminal device to perform: receiving, from a network device, a configuration for survival time; in accordance with a determination that the survival time is triggered, monitoring a successful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and in accordance with a determination that a condition for leaving the survival time is satisfied, performing at least one of: transmitting the data packet without packet data convergence protocol (PDCP) duplication; or changing a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity.

In a fifth aspect, there is provided a computer readable medium having instructions stored thereon. The instructions, when executed on at least one processor, cause the at least one processor to perform the method according to the first or second aspect of the present disclosure.

Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

Fig. 1 is a schematic diagram of a communication environment in which embodiments of the present disclosure can be implemented;

Fig. 2 illustrates a schematic diagram of a survival time in accordance with some embodiments of the present disclosure;

Fig. 3 illustrates a flow chart of an example method of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

Fig. 4 illustrates a signaling flow for entering the survival time according to some embodiments of the present disclosure;

Fig. 5 illustrates a signaling flow for entering the survival time according to some embodiments of the present disclosure;

Fig. 6 illustrates a signaling flow for entering the survival time according to some embodiments of the present disclosure;

Fig. 7 illustrates a signaling flow for entering the survival time according to some embodiments of the present disclosure;

Fig. 8 illustrates a signaling flow for entering the survival time according to some embodiments of the present disclosure;

Fig. 9 illustrates a flow chart of an example method of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

Fig. 10 illustrates a signaling flow for leaving the survival time according to some embodiments of the present disclosure;

Fig. 11 illustrates a signaling flow for leaving the survival time according to some embodiments of the present disclosure;

Fig. 12 illustrates a signaling flow for leaving the survival time according to some embodiments of the present disclosure;

Fig. 13 illustrates a signaling flow for leaving the survival time according to some embodiments of the present disclosure;

Fig. 14 illustrates a signaling flow for leaving the survival time according to some embodiments of the present disclosure; and

Fig. 15 is a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitations as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

As used herein, the term “terminal device” refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, or image capture devices such as digital cameras, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. The term “terminal device” can be used interchangeably with a UE, a mobile station, a subscriber station, a mobile terminal, a user terminal or a wireless device. In addition, the term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an Evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a Transmission Reception Point (TRP) , a Remote Radio Unit (RRU) , a radio head (RH) , a remote radio head (RRH) , a low power node such as a femto node, a pico node, and the like.

In one embodiment, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In one embodiment, the first network device may be a first RAT device and the second network device may be a second RAT device. In one embodiment, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device and the second network device. In one embodiment, first information may be transmitted to the terminal device from the first network device and second information may be transmitted to the terminal device from the second network device directly or via the first network device. In one embodiment, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

As used herein, the singular forms ‘a’ , ‘an’ and ‘the’ are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term ‘includes’ and its variants are to be read as open terms that mean ‘includes, but is not limited to. ’ The term ‘based on’ is to be read as ‘at least in part based on. ’ The term ‘one embodiment’ and ‘an embodiment’ are to be read as ‘at least one embodiment. ’ The term ‘another embodiment’ is to be read as ‘at least one other embodiment. ’ The terms ‘first, ’ ‘second, ’ and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as ‘best, ’ ‘lowest, ’ ‘highest, ’ ‘minimum, ’ ‘maximum, ’ or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

As mentioned above, several solutions have been proposed to provide efficient and reliable solutions for communication. A technology “survival time” has been proposed. The term “survival time” used herein refers to a time period the communication service may not meet the application's requirement before the communication service is deemed to be in an unavailable state. During the survival time, reliability of communications needs to be improved.

Therefore, solutions on properly triggering the survival time are needed. According to embodiments of the present disclosure, a terminal device receives, from a network device, a configuration for survival time. The terminal device monitors an unsuccessful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration. If a condition for triggering the survival time is satisfied, the terminal device transmits the data packet with packet data convergence protocol (PDCP) duplication or change a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity. In this way, it improves transmission reliability and reduces latency of transmissions.

Fig. 1 illustrates a schematic diagram of a communication system in which embodiments of the present disclosure can be implemented. The communication system 100, which is a part of a communication network, comprises a terminal device 110-1, a terminal device 110-2, ..., a terminal device 110-N, which can be collectively referred to as “terminal device (s) 110. ” The number N can be any suitable integer number.

The communication system 100 further comprises a network device 120. In the communication system 100, the network devices 120 and the terminal devices 110 can communicate data and control information to each other. The numbers of devices shown in Fig. 1 are given for the purpose of illustration without suggesting any limitations.

Communications in the communication system 100 may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) and the fifth generation (5G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Divided Multiple Address (CDMA) , Frequency Divided Multiple Address (FDMA) , Time Divided Multiple Address (TDMA) , Frequency Divided Duplexer (FDD) , Time Divided Duplexer (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Divided Multiple Access (OFDMA) and/or any other technologies currently known or to be developed in the future.

Embodiments of the present disclosure can be applied to any suitable scenarios. For example, embodiments of the present disclosure can be implemented at reduced capability NR devices. Alternatively, embodiments of the present disclosure can be implemented in one of the followings: NR multiple-input and multiple-output (MIMO) , NR sidelink enhancements, NR systems with frequency above 52.6GHz, an extending NR operation up to 71GHz, narrow band-Internet of Thing (NB-IOT) /enhanced Machine Type Communication (eMTC) over non-terrestrial networks (NTN) , NTN, UE power saving enhancements, NR coverage enhancement, NB-IoT and LTE-MTC, Integrated Access and Backhaul (IAB) , NR Multicast and Broadcast Services, or enhancements on Multi-Radio Dual-Connectivity.

Fig. 2 illustrates a schematic diagram of a survival time in accordance with some embodiments of the present disclosure. The terminal device 110-1 may perform transmissions to the network device 120. As shown in Fig. 2, the transmission 2050 is failed and the survival time can be triggered at the time instant 210. The terminal device 110-1 may improve the reliability of the transmissions after the time instant 210. If the transmission 2060 is successful, the terminal device 110-1 can leave the survival time.

Fig. 3 shows a flowchart of an example method 300 for entering the survival time in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 300 can be implemented at the terminal device, for example, the terminal device 110-1 as shown in Fig. 1.

At block 310, the terminal device 110-1 receives a configuration for survival time from the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

At block 320, the terminal device 110-1 monitors an unsuccessful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration. In some embodiments, the terminal device 110-1 may receive an indication of the unsuccessful transmission of the data packet. For example, the terminal device 110-1 may receive downlink control information (DCI) which comprises the indication of the unsuccessful transmission. The terminal device 110-1 may determine that the unsuccessful transmitted data packet comprises the data from the radio bearer or the logical channel configured with the survival time.

At block 330, if the condition for triggering the survival time is satisfied, the terminal device 110-1 transmits the data packet with the PDCP duplication. Alternatively or in addition, the terminal device 110-1 may change a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity.

An unsuccessful transmission of one data packet can be considered as the condition for the entering of survival time. In some embodiments, unsuccessful transmission of one data packet can be determined by unsuccessful transmission of MAC packet. In some embodiments, unsuccessful transmission of one data packet can be determined by unsuccessful initial transmission of the MAC data packet. In other words, a failure re-transmission at MAC entity should not be considered. Unsuccessful transmission of one data can be determined by a reception of a hybrid automatic repeat request non-acknowledged (HARQ-NACK) feedback for the initial transmission of the data packet. In this case, the corresponding data packet is an initial or a new transmission of the data packet. Alternatively, the network device 120 may only feedback HARQ-NACK for the initial transmission of a data packet.

Alternatively or in addition, unsuccessful transmission of one data can be determined by a reception of an UL-grant for retransmission (i.e. the new data indicator (NDI) bit is not toggled) and this is used for the first time of re-transmission. In other words that the previous MAC PDU is an initial transmission.

In other embodiments, unsuccessful transmission of one data can be determined by an expiration of a cg-RetransmissionTimer timer for one initial transmitted packet. The term “cg-RetransmissionTimer” used herein can refer to a duration after a configured grant (re) transmission of a HARQ process when the UE shall not autonomously retransmit that HARQ process.

In some embodiments, unsuccessful transmission of one data can be determined by a listen-before-talk (LBT) failure for the initial transmission of data packet. In some embodiments, unsuccessful transmission of one data can be determined by a reception of DCI information to indicate which radio bearer (ID) to enter survival state directly.

In some embodiments, unsuccessful transmission of one data can be determined by one unsuccessful transmission of one RLC packet. In some embodiments, unsuccessful transmission of one data can be determined by unsuccessful transmission of one PDCP packet.

In some embodiments, if the PDCP entity is configured with two RLC entities, the terminal device 110-1 may activate PDCP duplication upon entering survival time state. Alternatively, the PDCP entity can be configured with more than two RLC entities. In this case, before entering PDCP duplication, the PDCP duplication can be configured by the network device 120. For example, the network device 120 may pre-configure the RLC entities that shall be activated when the terminal device 110-1 enters survival time state. Upon the terminal device 110-1enters survival time state, the terminal device 110-1 may activate the RLC entities according to the network configuration if the RLC entities are not activated. Only as an example, for four RLC entities, the network device 120 may configure that RLC entity 1 and 2 shall be activated when the terminal device 110-1 enters survival time state. If the duplication state of the terminal device 110-1 is RLC 1 and 4 are activated before entering survival state, then the terminal device 110-1 may activate RLC entity 2.

Alternatively or in addition, the network device 120 may pre-configure the duplication status that the terminal device 110-1 shall use when the terminal device 110-1 enters survival time state. Upon the terminal device 110-1 enters survival time state, the terminal device 110-1 can apply the PDCP duplication state accordingly. For example, for RLC entities, the network device 120 may configure PDCP duplication state as 1 1 0 0 which means that RLC entities 1 and 2 are activated, and RLC entities 3 and 4 are deactivated. If the duplication state of the terminal device 110-1 is RLC 1 and 4 are activated before entering survival state, then the terminal device 110-1 may activate RLC entity 2, and deactivate RLC 4.

In some embodiments, only RLC unacknowledged mode (UM) can be supported for the radio bearer or the logical channel configured with the survival time. Alternatively, the terminal device 110-1 may determine whether the RLC packet consisted in the unsuccessfully transmitted MAC packet is the initial transmission of the RLC packet. In this way it avoids entering the survival time for the retransmission.

In other embodiments, the terminal device 110-1 may ensure that there is no segmentation of the RLC packets (initial transmitted) of the radio bearer configured with survival time. For example, the terminal device 110-1 may ensure no segmentation by using configuration grant and LCP restriction. Alternatively, the terminal device 110-1 may determine whether RLC PDUs corresponding to all RLC SDU segments are successfully transmitted.

In some embodiments, there may be two or more RLC entities activated before entering survival time. In this case, in some embodiments, the PDCP duplication should not be activated when not in survival time, i.e. only the primary RLC entity is activated. Alternatively, all activated RLC entities provide a successful or unsuccessful transmission indication to the PDCP entity, the PDCP entity can determine the unsuccessful transmission of one PDCP PDU if all activated RLC entities indicate failure transmission indication of the RLC SDU to the PDCP entity.

Some example embodiments of the present disclosure for entering the survival time are described with the reference to Fig. 4-8. As shown in Figs. 4-8, the terminal device 110-1 can comprise a RRC entity 1101, a MAC entity 1102, a PHY entity 1103, a PDCP entity 1104, and a RLC entity 1105.

Fig. 4 shows a signaling chart illustrating process 400 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 4001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 4005 to the MAC entity a survival time related configuration. The MAC entity use the survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 4006 an indication of an unsuccessful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 4010 the unsuccessful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 4015 that the unsuccessful transmitted MAC data packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may indicate 4020 the unsuccessful transmission of the data packet to other entities, for example, the RRC entity 1101, the PDCP entity 1104, the RLC entity 1105, or the PHY entity 1103.

After entering the survival time, at least one RLC entity for the PDCP duplication can be activated. The configuration of the PHY entity 1103 and the configuration of the MAC entity 1102 can be changed. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed.

Fig. 5 shows a signaling chart illustrating process 500 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 5001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 5005 the MAC entity a survival time related configuration. The MAC entity uses the survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 5006 an indication of an unsuccessful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 5010 the unsuccessful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 5015 that the unsuccessful transmitted data packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may determine the condition of survival time is fulfilled for the corresponding radio bearer, and indicate 5020 the unsuccessful transmission of the data packet or entering of survival time for the corresponding radio bearer to the RRC entity 1101.

After entering the survival time, the RRC entity 1101 may indicate 5025 to the PDCP entity 1104 to activate at least one RLC entity for the PDCP duplication. The RRC entity 1101 may indicate 5030 to the PHY entity 1103 to a configuration of the PHY entity 1103 and indicate 5035 to the MAC entity 1102 to change a configuration of the MAC entity 1102. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed.

Fig. 6 shows a signaling chart illustrating process 600 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 6001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 6005 the MAC entity a survival time related configuration and/or a reliability boost configuration. The MAC entity uses survival time related configuration and/or the reliability boost configuration to determine which radio bearer or logical channel is configured with the survival time.

The RRC entity may configure 6010 a configuration (i.e., the fourth configuration) corresponding to the survival time to the MAC entity 1102. The RRC entity may configure 6015 a configuration (i.e., the fifth configuration) corresponding to the survival time to the PHY entity 1103. The RRC entity may configure 6020 a configuration (i.e., the third configuration) corresponding to the survival time to the PDCP entity 1104.

In some embodiments, the network device 120 may transmit 6016 an indication of an unsuccessful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 6020 the unsuccessful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 6025 that the unsuccessful transmitted data packet comprises data from a radio bearer/logical channel configured with the survival time.

The MAC entity 1102 may determine that the condition of entering survival time is fulfilled, and may indicate 6030 to the PHY entity 1103 to change the configuration at the PHY entity. The MAC entity 1102 may indicate 6035 to the PDCP entity 1104 to change the configuration at the PDCP entity. The MAC entity 1102 may change 6040 the MAC configuration itself. After receiving the indication from the MAY entity 1102, the PDCP entity 1104 may activate 6045 at least one RLC entity for the PDCP duplication. The MAC entity 1102 may change the MAC configuration based on the configuration (i.e., the fourth configuration) corresponding to the survival time. The PHY entity 1103 may change the PHY configuration based the configuration (i.e., the fifth configuration) corresponding to the survival time. The PDCP entity 1104 may change the PDCP configuration based on the configuration (i.e., the third configuration) corresponding to the survival time. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed.

Fig. 7 shows a signaling chart illustrating process 700 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 7001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may configure 7005 a MAC entity survival time related configuration. The MAC entity uses survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 7006 an indication of an unsuccessful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 7010 the unsuccessful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 7015 that the unsuccessful transmitted data packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may indicate 7020 the unsuccessful transmission of the data packet to the RLC entity 1105.

The RLC entity 1105 may detect 7025 the unsuccessful transmission of a RLC packet considering the segmentation and/or retransmission. In some embodiments, the RLC entity 1105 may determine whether the RLC packet consisted in the unsuccessful transmitted MAC packet is the initial transmission of the RLC packet. If the RLC entity 1105 determines the initial transmission of the RLC SDU or RLC PDU is unsuccessful, the unsuccessful transmission of RLC packets is detected. In some embodiments, the RLC entity 1105 may also determine if a transmission of at least one segmentation of one RLC SDU fails, the unsuccessful transmission of the RLC packet is detected.

The RLC entity 1105 may indicate 7026 the RRC entity 1101 the unsuccessful transmission of a RLC packet or the entering of survival time. After entering the survival time, the RRC entity 1101 may activate 7030 at least one RLC entity for the PDCP duplication. The RRC entity 1101 may change a configuration of the PHY entity 1103 and a configuration of the MAC entity 1102.

The RLC entity 1105 may also indicate to the PDCP entity 1104, the MAC entity 1102 and the PHY entity 1103 to change their configurations. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed.

Fig. 8 shows a signaling chart illustrating process 800 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 8001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 8005 to MAC entity 1102 a survival time related configuration. The MAC entity 1102 uses survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 8006 an indication of an unsuccessful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 8010 the unsuccessful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 8015 that the unsuccessful transmitted data packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may indicate 8020 the unsuccessful transmission of the data packet to the RLC entity 1105.

The RLC entity 1105 may detect 8025 the unsuccessful transmission of a RLC packet considering the segmentation and/or retransmission. In some embodiments, the RLC entity 1105 may determine whether the RLC packet consisted in the unsuccessful transmitted MAC packet is the initial transmission of the RLC packet. If the RLC entity 1105 may determine the initial transmission of the RLC SDU or RLC PDU is unsuccessful, the unsuccessful transmission of RLC packets is detected. In some embodiments, if a transmission of at least one segmentation of one RLC SDU fails, the unsuccessful transmission of the RLC packet is detected., the unsuccessful transmission of the RLC packet is detected. In this case, the RLC entity 1105 may indicate 8030 the unsuccessful transmission of the RLC packet to the PDCP entity 1104.

The PDCP entity 1104 may detect 8035 the unsuccessful transmission of the RLC packet considering the PDCP duplication. As mentioned above, in some embodiments, there may be two or more RLC entities activated before entering survival time. In this case, all activated RLC entities can provide a successful or unsuccessful transmission indication to the PDCP entity 1104. The PDCP entity 1104 can determine the unsuccessful transmission of one PDCP PDU if all activated RLC entities indicate failure transmission indication of the RLC packet correspond to the same PDCP PDU to the PDCP entity 1104.

The PDCP entity 1105 may indicate to the RRC entity 1101 the unsuccessful transmission of the PDCP packet or the entering of survival time. The RRC entity may further indicate the MAC entity 1102 and the PHY entity 1103 to change their configurations. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed. After entering the survival time, the PDCP entity 1101 may activate at least one RLC entity for the PDCP duplication.

The PDCP entity 1105 may also indicate to the MAC entity 1102 and the PHY entity 1103 to change their configurations for entering survival time. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed. The PDCP entity 1105 may also active at least one RLC entity for PDCP duplication for entering survival time.

Fig. 9 shows a flowchart of an example method 900 for leaving the survival time in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 900 can be implemented at the terminal device, for example, the terminal device 110-1 as shown in Fig. 1.

At block 910, the terminal device 110-1 receives a configuration for survival time from the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

At block 920, the terminal device 110-1 monitors a successful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration if the survival time is triggered. In some embodiments, the terminal device 110-1 may receive an indication of the successful transmission of the data packet. For example, the terminal device 110-1 may receive downlink control information (DCI) which comprises the indication of the successful transmission. The terminal device 110-1 may determine that the data packet comprises the data from the radio bearer or the logical channel configured with the survival time.

At block 930, if the condition for leaving the survival time is satisfied, the terminal device 110-1 transmits the data packet without the PDCP duplication. Alternatively or in addition, the terminal device 110-1 may change a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity.

One successful transmission of one data packet can be considered as the condition for leaving the survival time. In some embodiments, unsuccessful transmission of one data packet can be determined by unsuccessful transmission of MAC packets. In some embodiments, successful transmission of one data packet can be determined by successful initial transmitted MAC data packet. Successful transmission of one data can be determined by a reception of a HARQ-ACK feedback for the one initial transmission of the data packet. Alternatively, the network device 120 may only feedback HARQ-ACK for the initial transmission of the data packet. Alternatively or in addition, successful transmission of one data can be determined by a reception of a dynamic UL grant for a new initial transmission (i.e., the NDI is toggled) and previous transmission being an initial transmission.

In other embodiments, successful transmission of one data can be determined by an expiration of a configuredGrantTimer for the corresponding HARQ process. The configuredGrantTimer can start upon transmission on CG resource, and re-start upon dynamic re-transmission. Upon expiry, it considers that the MAC PDU is successfully received.

In some embodiments, successful transmission of one data can be determined by a reception of downlink control information indicating which radio bearer to leave survival time state directly. Upon receiving the DCI, the MAC entity or PHY entity of the terminal device 110-1 can indicate the upper entity to leave survival time.

Alternatively or in addition, successful transmission of one data can be determined by a reception of a MAC control element (CE) which can indicate which DRB terminates/leave the survival time.

In some embodiments, successful transmission of one data can be determined by one successful transmission of one RLC packet. In some embodiments, successful transmission of one data can be determined by successful transmission of one PDCP packet.

In some embodiments, the PDCP duplication can be with two RLC entities. In this case, if the terminal device 110-1 leaves/exists the survival time, the terminal device 110-1 may deactivate the PDCP duplication.

In other embodiments, the PDCP duplication can be with more than two RLC entities. In this case, if the terminal device 110-1 leaves/exists the survival time, the terminal device 110-1 may deactivate the PDCP duplication. Alternatively or in addition, the terminal device 110-1 may fallback to an original PDCP duplication state before entering the survival time state. In some embodiments, the terminal device 110-1 may apply a PDCP duplication status which is pre-configured by the network device 120. The network device 120 may pre-configure PDCP duplication status to be used when the terminal device 110-1 leaves the survival time, via RRC signaling. In some embodiments, the network device 120 may pre-configure one or more RLC entities which should be deactivated when the terminal device 110-1 leaves the survival time. In some embodiments, the terminal device 110-1 may deactivate at least one RLC entity which is not the primary RLC, if the ACK corresponding to the RLC entity is not received or a NACK corresponding to the RLC entity is received. In other embodiments, the terminal device 110-1 may apply the PDCP duplication state carried in one of: a MAC CE, DCI or RRC signaling.

In some embodiments, only RLC unacknowledged mode (UM) can be supported for the radio bearer or the logical channel configured with the survival time. Alternatively, the terminal device 110-1 may determine whether the RLC packet consisted in the successfully transmitted MAC packet is the initial transmission of the RLC packet. In this way it avoids leaving the survival time for the retransmission.

In some embodiments, there may be two or more RLC entities activated before entering survival time. In this case, in some embodiments, the PDCP duplication should not be activated when not in survival time, i.e. only the primary RLC entity is activated. Alternatively, all activated RLC entities provide a successful or unsuccessful transmission indication to the PDCP entity, the PDCP entity can determine the successful transmission of one PDCP PDU if at least one of the activated RLC entities indicate he successful transmission of the RLC SDT to the PDCP entities.

Some example embodiments of the present disclosure for leaving the survival time are described with the reference to Fig. 10-14. As shown in Figs. 10-14, the terminal device 110-1 can comprise a RRC entity 1101, a MAC entity 1102, a PHY entity 1103, a PDCP entity 1104, and a RLC entity 1105.

Fig. 10 shows a signaling chart illustrating process 1000 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 10001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 10005 to the MAC entity 1102 a survival time related configuration. The MAC entity may use survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 10006 an indication of a successful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 10010 the successful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 10015 that the successful transmitted MAC packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may indicate 10020 the successful transmission of the data packet to other entities, for example, the RRC entity 1101, the PDCP entity 1104, the RLC entity 1105, or the PHY entity 1103.

After entering the survival time, at least one RLC entity for the PDCP duplication can be deactivated. The configuration of the PHY entity 1103 and the configuration of the MAC entity 1102 can be changed. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed.

Fig. 11 shows a signaling chart illustrating process 1100 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 11001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 11005 to the MAC entity a survival time related configuration. The MAC entity may use the survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 11006 an indication of a successful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 11010 the successful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 11015 that the successful transmitted MAC packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may indicate 11020 the successful transmission of the data packet to the RRC entity 1101.

After entering the survival time, the RRC entity 1101 may indicate 11025 the PDCP entity 1104 to deactivate at least one RLC entity for the PDCP duplication. The RRC entity 1101 may indicate 11030 the PHY entity 11030 to change a configuration of the PHY entity 1103 and indicate 11035 the MAC entity 1102 to change a configuration of the MAC entity 1102. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed.

Fig. 12 shows a signaling chart illustrating process 1200 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 12001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 12005 to the MAC entity survival time related configuration. The MAC entity uses the survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

The RRC entity may configure 12010 a configuration (i.e., the fourth configuration) corresponding to the survival time to the MAC entity 1102. The RRC entity may configure 12015 a configuration (i.e., the fifth configuration) corresponding to the survival time to the PHY entity 1103. The RRC entity may configure 12020 a configuration (i.e., the third configuration) corresponding to the survival time to the PDCP entity 1104.

In some embodiments, the network device 120 may transmit 12016 an indication of a successful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 12020 the successful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 12025 that the successful transmitted data packet comprises data from a radio bearer/logical channel configured with the survival time.

The MAC entity 1102 may indicate 12030 to the PHY entity 1103 to change the configuration at the PHY entity. The MAC entity 1102 may indicate 12035 to the PDCP entity 1104 to change the configuration at the PDCP entity. The MAC entity 1102 may change 12040 the MAC configuration itself. After receiving the indication from the MAY entity 1102, the PDCP entity 1104 may deactivate 12045 at least one RLC entity for the PDCP duplication. The MAC entity 1102 may change the MAC configuration based on the configuration (i.e., the fourth configuration) corresponding to the survival time. The PHY entity 1103 may change the PHY configuration based the configuration (i.e., the fifth configuration) corresponding to the survival time. The PDCP entity 1104 may change the PDCP configuration based on the configuration (i.e., the third configuration) corresponding to the survival time to. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed.

Fig. 13 shows a signaling chart illustrating process 1300 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 13001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 13005 to the MAC entity 1102 a survival time related configuration and. The MAC entity may use survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 13006 an indication of a successful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 13010 the successful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 13015 that the successful transmitted data packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may indicate 13020 the successful transmission of the data packet to the RLC entity 1105.

The RLC entity 1105 may detect 13025 the successful transmission of a RLC packet considering the segmentation and/or retransmission. In some embodiments, the RLC entity 1105 may determine whether the RLC packet consisted in the successful transmitted MAC packet is the initial transmission of the RLC packet. If the RLC entity 1105 determines the initial transmission of the SDU or RLC PDU is successful, the successful transmission of RLC packets is detected. In some embodiments, the RLC entity 1105 may determine whether the RLC PDUs corresponding to all RLC service data unit (SDU) segments are successfully transmitted. In this case, if all transmissions of the RLC PDUs are successful, the RLC entity 1105 may determine that the transmission of the RLC packet is successful.

The RLC entity 1105 may indicate 13026 the RRC entity 1101 the successful transmission of a RLC packet or leaving survival time. After leaving the survival time, at least one RLC entity for the PDCP duplication can be deactivated. The RRC entity 1101 may change a configuration of the PHY entity 1103 and a configuration of the MAC entity 1102.

Fig. 14 shows a signaling chart illustrating process 1400 for entering the survival time among entities of the terminal device 110-1 according to some example embodiments of the present disclosure.

The network device 120 may transmit 14001 a configuration for survival time to the RRC entity 1101 of the network device 120. For example, the configuration for the survival time can be transmitted via radio resource control (RRC) signaling. The configuration may indicate at least one radio bearer configured with the survival time. Alternatively or in addition, the configuration may indicate at least one logical channel configured with the survival time.

The RRC entity 1101 may indicate 14005 to the MAC entity 1102 a survival time related configuration. The MAC entity may use the survival time related configuration to determine which radio bearer or logical channel is configured with the survival time.

In some embodiments, the network device 120 may transmit 14006 an indication of a successful transmission of a data packet to the PHY entity 1103 of the terminal device 110-1. The indication can be included in downlink control information.

The PHY entity 1103 may indicate 14010 the successful transmission of the data packet to the MAC entity 1102. The MAC entity 1102 may detect 14015 that the successful transmitted data packet comprises data from a radio bearer/logical channel configured with the survival time. The MAC entity 1102 may indicate 14020 the successful transmission of the data packet to the RLC entity 1105.

The RLC entity 1105 may detect 14025 the successful transmission of a RLC packet considering the segmentation and/or retransmission. In some embodiments, the RLC entity 1105 may determine whether the RLC packet consisted in the successful transmitted MAC packet is the initial transmission of the RLC packet. If the RLC entity 1105 may determine the initial transmission of the RLC SDU or RLC PDU is successful, the successful transmission of RLC packets is detected. In some embodiments, the RLC entity 1105 may determine whether the RLC PDUs corresponding to all RLC service data unit (SDU) segments are successfully transmitted. In some embodiments, if all transmissions of the RLC PDUs are successful, the RLC entity 1105 may determine that the transmission of the RLC packet is successful. In this situation, the RLC entity 1105 may indicate 14030 the successful transmission of the RLC packet to the PDCP entity 1104.

The PDCP entity 1104 may detect 14035 the successful transmission of the RLC packet considering the PDCP duplication. As mentioned above, in some embodiments, there may be two or more RLC entities activated before entering survival time. In this case, all activated RLC entities can provide a successful or unsuccessful transmission indication to the PDCP entity 1104. The PDCP can determine the successful transmission of one PDCP PDU if at least one of the activated RLC entities indicate he successful transmission of the RLC SDU corresponding to the same PDU to the PDCP entities.

The PDCP entity 1105 may indicate to the RRC entity 1101 the successful transmission of the PDCP packet or the leaving of survival time. The RRC entity may further indicate the MAC entity 1102 and the PHY entity 1103 to change their configurations. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed. After leaving the survival time, at least one RLC entity for the PDCP duplication can deactivated.

The PDCP entity 1105 may also indicate to the MAC entity 1102 and the PHY entity 1103 to change their configurations for leaving survival time. For example, the logical channel priority (LCP) at the MAC entity 1102 can be changed. Alternatively or in addition, modulation and coding scheme (MCS) at the PHY entity 1103 can be changed. The PDCP entity 1105 may also active at least one RLC entity for PDCP duplication for leaving survival time.

In some embodiments, a terminal device comprises circuitry configured to receive, from a network device, a configuration for survival time; monitor an unsuccessful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and in accordance with a determination that a condition for triggering the survival time is satisfied, perform at least one of: transmitting the data packet with packet data convergence protocol (PDCP) duplication; or changing a first configuration of a physical (PHY) entity 1 and a second configuration of a medium access control (MAC) entity.

In some embodiments, the configuration indicates at least one radio bearer configured with the survival time.

In some embodiments, the terminal device comprises circuitry configured to monitor the unsuccessful transmission of the data packet on the radio bearer or the logical channel configured with the survival time based on the configuration by: receiving, at a physical (PHY) entity of the terminal device and from the network device, an indication of the unsuccessful transmission of the data packet; and determining, at a medium access control (MAC) entity of the terminal device, that the data packet comprises data from the radio bearer configured with the survival time based on the configuration.

In some embodiments, the terminal device comprises circuitry configured to indicate, by the MAC entity of the terminal device and to a radio resource control (RRC) entity of the terminal device, the unsuccessful transmission of the data packet; and the terminal device comprises circuitry configured to transmit the data packet with the PDCP duplication by: activating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and/or the terminal device comprises circuitry configured to change the first configuration and the second configuration by: changing, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity.

In some embodiments, the terminal device comprises circuitry configured to configure, by a radio resource control (RRC) entity of the terminal device, a third configuration corresponding to the survival time to a PDCP entity of the terminal device; configure, by a radio resource control (RRC) entity of the terminal device, a fourth configuration corresponding to the survival time to the MAC entity; and configure, by a radio resource control (RRC) entity of the terminal device, a fifth configuration corresponding to the survival time to the PHY entity of the terminal device.

In some embodiments, the terminal device comprises circuitry configured to indicate, by the MAC entity and to the PDCP entity and the PHY entity, to change configurations.

In some embodiments, the terminal device comprises circuitry configured to: change, by the MAC entity, a MAC configuration based on the fourth configuration; change, by the PHY entity, a PHY configuration based on the fifth configuration; and the terminal device comprises circuitry configured to transmit the data packet with the PDCP duplication by activating, by the PDCP entity, at least one RLC entity for the duplication based on the third configuration.

In some embodiments, the data packet on the radio bearer or the logical channel configured with survival time is in a radio link control (RLC) unacknowledged mode.

In some embodiments, the terminal device comprises circuitry configured to: indicate, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the unsuccessful transmission of the data packet; determine, at the RLC entity, whether a RLC packet is an initial transmission of the RLC packet; in accordance with a determination that the RLC packet is the initial transmission of the RLC packet, perform at least one of: indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations; or indicating by the RLC entity to the RRC entity, and activating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and changing, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity.

In some embodiments, there is no segmentation of a radio link control (RLC) packet related to the data packet on the radio bearer configured with the survival time based on the configuration.

In some embodiments, the terminal device comprises circuitry configured to: indicate, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the unsuccessful transmission of the data packet; determine, at the RLC entity, whether RLC protocol data units (PDUs) corresponding to all RLC service data unit (SDU) segments are successfully transmitted; and in accordance with a determination that a transmission of at least one RLC PDU fails, indicate, to the MAC entity and the PHY entity, to change configurations; or indicate, by the RLC entity to the RRC entity, that the RRC entity further indicates the PDCP entity, MAC entity and the PHY entity to change configurations.

In some embodiments, the terminal device comprises circuitry configured to: indicate, by the MAC entity of the terminal device and to a set of radio link control (RLC) entities of the terminal device, the unsuccessful transmission of the data packet; indicate, by the set of RLC entities and to the PDCP entity, a successful or a unsuccessful transmissions of a RLC packet; in accordance with a determination that all of the set of RLC entities indicate that the unsuccessful transmission of the RLC packet, perform at least one of: indicating, by the PDCP entity and to the MAC entity and the PHY entity, to change configurations; activating, by the PDCP entity, a radio link control (RLC) entity for the PDCP duplication; or indicating, by the PDCP entity to the RRC entity, that the RRC entity further indicates the MAC entity and the PHY entity to change configurations.

In some embodiments, the terminal device comprises circuitry configured to determine that the data packet comprises data from the radio bearer configured with the survival time, in accordance with a determination that at least one of the following is met: an initial transmission of the data packet is failed, or downlink control information received from the network device indicating to trigger the survival time.

In some embodiments, an initial transmission of the data packet being failed comprises at least one of: receiving, from the network device, a hybrid automatic repeat request non-acknowledge (HARQ-NACK) for the initial transmission; receiving an uplink grant with new data indicator not toggled; an expiration of configured grant retransmission timer for the initial transmission of the data packet; or a listen-before-talk failure for the initial transmission of the data packet.

In some embodiments, no duplication is activated out of the survival time.

In some embodiments, the terminal device comprises circuitry configured to receive, a further configuration indicating a duplication status for the terminal device when the survival time is triggered.

In some embodiments, a terminal device comprises circuitry configured to receive, from a network device, a configuration for survival time; in accordance with a determination that the survival time is triggered, monitor a successful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and in accordance with a determination that a condition for leaving the survival time is satisfied, perform at least one of: transmitting the data packet without packet data convergence protocol (PDCP) duplication; or changing a first configuration of a physical (PHY) entity 1 and a second configuration of a medium access control (MAC) entity.

In some embodiments, the configuration for leaving the survival time indicates at least one radio bearer configured with the survival time.

In some embodiments, the terminal device comprises circuitry configured to monitor the successful transmission of the data packet on the radio bearer or the logical channel configured with the survival time based on the configuration by: receiving, at a physical (PHY) entity of the terminal device and from the network device, an indication of the successful transmission of the data packet; and determining, at a medium access control (MAC) entity of the terminal device, that the data packet comprises data from the radio bearer or the logical channel configured with the survival time based on the configuration.

In some embodiments, the terminal device comprises circuitry configured to indicate, by the MAC entity of the terminal device and to a radio resource control (RRC) entity of the terminal device, the successful transmission of the data packet; and the terminal device comprises circuitry configured to transmit the data packet without the PDCP duplication by: deactivating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and the terminal device comprises circuitry configured to change the first configuration and the second configuration by: changing, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity; or indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations.

In some embodiments, the terminal device comprises circuitry configured to configure, by a radio resource control (RRC) entity of the terminal device, a third configuration corresponding to leaving the survival time to a PDCP entity of the terminal device; configure, by a radio resource control (RRC) entity of the terminal device, a fourth configuration corresponding to leaving the survival time to the MAC entity; and configure, by a radio resource control (RRC) entity of the terminal device, a fifth configuration corresponding to leaving the survival time to the PHY entity of the terminal device.

In some embodiments, the terminal device comprises circuitry configured to change, by the MAC entity, a MAC configuration based on the fourth configuration; change, by the PHY entity, a PHY configuration based on the fifth configuration; and the terminal device comprises circuitry configured to transmit the data packet without the PDCP duplication by: deactivating, by the PDCP entity, at least one RLC entity for the duplication based on the third configuration.

In some embodiments, the terminal device comprises circuitry configured to indicate, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the successful transmission of the data packet; determine, at the RLC entity, whether a RLC packet is an initial transmission of the RLC packet; in accordance with a determination that the RLC packet is the initial transmission of the RLC packet, perform at least one of: indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations; or indicate by the RLC entity to the RRC entity, and deactivating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and change, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity.

In some embodiments, the terminal device comprises circuitry configured to indicate, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the successful transmission of the data packet; determine, at the RLC entity, whether RLC protocol data units (PDUs) corresponding to all RLC service data unit (SDU) segments are successfully transmitted; and in accordance with a determination that all RLC PDUs are successfully transmitted, indicate, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations; or indicate, by the RLC entity to the RRC entity, that the RRC entity further indicates the PDCP entity, MAC entity and the PHY entity to change configurations.

In some embodiments, the terminal device comprises circuitry configured to indicate, by the MAC entity of the terminal device and to a set of radio link control (RLC) entities of the terminal device, the unsuccessful transmission of the data packet; indicate, by the set of RLC entities and to the PDCP entity, a successful or a unsuccessful transmissions of a RLC packet; in accordance with a determination that at least one of the set of RLC entity indicates the successful transmission of the RLC packet, perform at least one of: indicating, by the PDCP entity and to the MAC entity and the PHY entity, to change configurations; deactivating, by the PDCP entity, a radio link control (RLC) entity for the PDCP duplication; or indicating, by the PDCP entity to the RRC entity, that the RRC entity further indicates the MAC entity and the PHY entity to change configurations.

In some embodiments, determining that the data packet comprises data from the radio bearer configured with the survival time, in accordance with a determination that at least one of the following is met: an initial transmission of the data packet is successful, downlink control information received from the network device indicating to leaving the survival time, or a medium access control control element (MEC CE) received from the network device indicating to leaving the survival time.

In some embodiments, an initial transmission of the data packet being successful comprises at least one of: receiving, from the network device, a hybrid automatic repeat request acknowledge (HARQ-ACK) for the initial transmission; receiving an uplink grant for transmission with a toggled new data indicator; or an expiration of configured grant timer for the HARQ of the data packet.

In some embodiments, the terminal device comprises circuitry configured to apply an original duplication status which is applied before triggering the survival time; apply a duplication status, wherein the duplication status is received via one of: radio resource control signaling, a medium access control control element (MAC CE) , or downlink control information; or deactivate a radio link control (RLC) entity on which a NACK is received.

Fig. 15 is a simplified block diagram of a device 1500 that is suitable for implementing embodiments of the present disclosure. The device 1500 can be considered as a further example implementation of the network device 120, or the terminal device 110 as shown in Fig. 1. Accordingly, the device 1500 can be implemented at or as at least a part of the terminal device 110, or the network device 120.

As shown, the device 1500 includes a processor 1510, a memory 1520 coupled to the processor 1510, a suitable transmitter (TX) and receiver (RX) 1540 coupled to the processor 1510, and a communication interface coupled to the TX/RX 1540. The memory 1510 stores at least a part of a program 1530. The TX/RX 1540 is for bidirectional communications. The TX/RX 1540 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 1530 is assumed to include program instructions that, when executed by the associated processor 1510, enable the device 1500 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to Figs. 3 to 14. The embodiments herein may be implemented by computer software executable by the processor 1510 of the device 1500, or by hardware, or by a combination of software and hardware. The processor 1510 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 1510 and memory 1520 may form processing means adapted to implement various embodiments of the present disclosure.

The memory 1520 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 1520 is shown in the device 1500, there may be several physically distinct memory modules in the device 1500. The processor 1510 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 1500 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to Figs. 2 to 10. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A communication method, comprising:

receiving, at a terminal device and from a network device, a configuration for survival time;

monitoring an unsuccessful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and

in accordance with a determination that a condition for triggering the survival time is satisfied, performing at least one of:

transmitting the data packet with packet data convergence protocol (PDCP) duplication; or

changing a first configuration of a physical (PHY) entity 1 and a second configuration of a medium access control (MAC) entity.
The method of claim 1, wherein the configuration indicates at least one radio bearer configured with the survival time.
The method of claim 1, wherein monitoring the unsuccessful transmission of the data packet on the radio bearer or the logical channel configured with the survival time based on the configuration comprises:

receiving, at a physical (PHY) entity of the terminal device and from the network device, an indication of the unsuccessful transmission of the data packet; and

determining, at a medium access control (MAC) entity of the terminal device, that the data packet comprises data from the radio bearer configured with the survival time based on the configuration.
The method of claim 3, further comprising:

indicating, by the MAC entity of the terminal device and to a radio resource control (RRC) entity of the terminal device, the unsuccessful transmission of the data packet; and

wherein transmitting the data packet with the PDCP duplication comprises:

activating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and/or

wherein changing the first configuration and the second configuration comprises:

changing, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity.
The method of claim 3, further comprising:

configuring, by a radio resource control (RRC) entity of the terminal device, a third configuration corresponding to the survival time to a PDCP entity of the terminal device;

configuring, by a radio resource control (RRC) entity of the terminal device, a fourth configuration corresponding to the survival time to the MAC entity; and

configuring, by a radio resource control (RRC) entity of the terminal device, a fifth configuration corresponding to the survival time to the PHY entity of the terminal device.
The method of claim 5, further comprising:

indicating, by the MAC entity and to the PDCP entity and the PHY entity, to change configurations.
The method of claim 6, further comprising at least one of:

changing, by the MAC entity, a MAC configuration based on the fourth configuration;

changing, by the PHY entity, a PHY configuration based on the fifth configuration; and wherein transmitting the data packet with the PDCP duplication comprises:

activating, by the PDCP entity, at least one RLC entity for the duplication based on the third configuration.
The method of claim 1, wherein the data packet on the radio bearer or the logical channel configured with survival time is in a radio link control (RLC) unacknowledged mode.
The method of claim 3, further comprising:

indicating, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the unsuccessful transmission of the data packet;

determining, at the RLC entity, whether a RLC packet is an initial transmission of the RLC packet;

in accordance with a determination that the RLC packet is the initial transmission of the RLC packet, performing at least one of:

indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations; or

indicating by the RLC entity to the RRC entity, and activating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and

changing, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity.
The method of claim 1, wherein there is no segmentation of a radio link control (RLC) packet related to the data packet on the radio bearer configured with the survival time based on the configuration.
The method of claim 3, further comprising:

indicating, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the unsuccessful transmission of the data packet;

in accordance with a determination that a transmission of at least one RLC PDU fails, indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations; or

indicating, by the RLC entity to the RRC entity, that the RRC entity further indicates the PDCP entity, MAC entity and the PHY entity to change configurations.
The method of claim 3, further comprising:

indicating, by the MAC entity of the terminal device and to a set of radio link control (RLC) entities of the terminal device, the unsuccessful transmission of the data packet;

indicating, by the set of RLC entities and to the PDCP entity, a successful or a unsuccessful transmissions of a RLC packet;

in accordance with a determination that all of the set of RLC entities indicate that the unsuccessful transmission of the RLC packet, performing at least one of

indicating, by the PDCP entity and to the MAC entity and the PHY entity, to change configurations;

activating, by the PDCP entity, a radio link control (RLC) entity for the PDCP duplication; or

indicating, by the PDCP entity to the RRC entity, that the RRC entity further indicates the MAC entity and the PHY entity to change configurations.
The method of claim 3, wherein determining that the data packet comprises data from the radio bearer configured with the survival time, in accordance with a determination that at least one of the following is met:

an initial transmission of the data packet is failed, or

downlink control information received from the network device indicating to trigger the survival time.
The method of claim 13, wherein an initial transmission of the data packet being failed comprises at least one of:

receiving, from the network device, a hybrid automatic repeat request non-acknowledge (HARQ-NACK) for the initial transmission;

receiving an uplink grant with new data indicator not toggled;

an expiration of configured grant retransmission timer for the initial transmission of the data packet; or

a listen-before-talk failure for the initial transmission of the data packet.
The method of claim 1, wherein no duplication is activated out of the survival time.
The method of claim 1, further comprising:

receiving, a further configuration indicating a duplication status for the terminal device when the survival time is triggered.
A communication method, comprising:

receiving, at a terminal device and from a network device, a configuration for survival time;

in accordance with a determination that the survival time is triggered, monitoring a successful transmission of a data packet on a radio bearer or a logical channel configured with the survival time based on the configuration; and

in accordance with a determination that a condition for leaving the survival time is satisfied, performing at least one of:

transmitting the data packet without packet data convergence protocol (PDCP) duplication; or

changing a first configuration of a physical (PHY) entity and a second configuration of a medium access control (MAC) entity.
The method of claim 17, wherein the configuration indicates at least one radio bearer configured with the survival time.
The method of claim 17, wherein monitoring the successful transmission of the data packet on the radio bearer or the logical channel configured with the survival time based on the configuration comprises:

receiving, at a physical (PHY) entity of the terminal device and from the network device, an indication of the successful transmission of the data packet; and

determining, at a medium access control (MAC) entity of the terminal device, that the data packet comprises data from the radio bearer or the logical channel configured with the survival time based on the configuration.
The method of claim 19, further comprising:

indicating, by the MAC entity of the terminal device and to a radio resource control (RRC) entity of the terminal device, the successful transmission of the data packet; and

wherein transmitting the data packet without the PDCP duplication comprises:

deactivating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and

wherein changing the first configuration and the second configuration comprises:

changing, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity; or

indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations.
The method of claim 19, further comprising:

configuring, by a radio resource control (RRC) entity of the terminal device, a third configuration corresponding to leaving the survival time to a PDCP entity of the terminal device;

configuring, by a radio resource control (RRC) entity of the terminal device, a fourth configuration corresponding to leaving the survival time to the MAC entity; and

configuring, by a radio resource control (RRC) entity of the terminal device, a fifth configuration corresponding to leaving the survival time to the PHY entity of the terminal device.
The method of claim 21, further comprising:

indicating, by the MAC entity and to the PDCP entity and the PHY entity, to change configurations.
The method of claim 21, further comprising at least one of:

changing, by the MAC entity, a MAC configuration based on the fourth configuration;

changing, by the PHY entity, a PHY configuration based on the fifth configuration; and wherein transmitting the data packet without the PDCP duplication comprises:

deactivating, by the PDCP entity, at least one RLC entity for the duplication based on the third configuration.
The method of claim 17, wherein the data packet on the radio bearer or the logical channel configured with survival time is in a radio link control (RLC) unacknowledged mode.
The method of claim 19, further comprising:

indicating, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the successful transmission of the data packet;

determining, at the RLC entity, whether a RLC packet is an initial transmission of the RLC packet;

in accordance with a determination that the RLC packet is the initial transmission of the RLC packet, performing at least one of:

indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations; or

indicating by the RLC entity to the RRC entity, and deactivating, by the RRC entity of the terminal device, a radio link control (RLC) entity for the PDCP duplication; and

changing, by the RRC entity of the terminal device, the first configuration of the PHY entity and the second configuration of the MAC entity.
The method of claim 17, wherein there is no segmentation of a radio link control (RLC) packet related to the data packet on the radio bearer configured with the survival time based on the configuration.
The method of claim 19, further comprising:

indicating, by the MAC entity of the terminal device and to a radio link control (RLC) entity of the terminal device, the successful transmission of the data packet;

determining, at the RLC entity, whether RLC protocol data units (PDUs) corresponding to all RLC service data unit (SDU) segments are successfully transmitted; and

in accordance with a determination that all RLC PDUs are successfully transmitted, indicating, by the RLC entity and to the PDCP entity, the MAC entity and the PHY entity, to change configurations; or

indicating, by the RLC entity to the RRC entity, that the RRC entity further indicates the PDCP entity, MAC entity and the PHY entity to change configurations.
The method of claim 19, further comprising:

indicating, by the MAC entity of the terminal device and to a set of radio link control (RLC) entities of the terminal device, the unsuccessful transmission of the data packet;

indicating, by the set of RLC entities and to the PDCP entity, a successful or a unsuccessful transmissions of a RLC packet;

in accordance with a determination that at least one of the set of RLC entity indicates the successful transmission of the RLC packet, performing at least one of:

indicating, by the PDCP entity and to the MAC entity and the PHY entity, to change configurations;

deactivating, by the PDCP entity, a radio link control (RLC) entity for the PDCP duplication; or

indicating, by the PDCP entity to the RRC entity, that the RRC entity further indicates the MAC entity and the PHY entity to change configurations.
The method of claim 19, wherein determining that the data packet comprises data from the radio bearer configured with the survival time, in accordance with a determination that at least one of the following is met:

an initial transmission of the data packet is successful,

downlink control information received from the network device indicating to leaving the survival time, or

a medium access control control element (MEC CE) received from the network device indicating to leaving the survival time.
The method of claim 29, wherein an initial transmission of the data packet being successful comprises at least one of:

receiving, from the network device, a hybrid automatic repeat request acknowledge (HARQ-ACK) for the initial transmission;

receiving an uplink grant for transmission with a toggled new data indicator ; or

an expiration of configured grant timer for the HARQ of the data packet.
The method of claim 17, further comprising at least one of:

applying an original duplication status which is applied before triggering the survival time;

applying a duplication status, wherein the duplication status is received via one of: radio resource control signaling, a medium access control control element (MAC CE) , or downlink control information; or

deactivating a radio link control (RLC) entity on which a NACK is received.
A terminal device comprising:

circuitry, configured to perform the method according to any one of claims 1-16 or any one of claims 17-31.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method according to any of claims 1-16 or any one of claims 17-31.