Performance enhancement of pusch repetition method in wireless communication system

Abstract

A method of enhancing performance of a physical uplink shared channel, PUSCH, repetition type B, for repetitions in a PUSCH transmission of a UE to a base station of a wireless communication network is disclosed. The method is performed by the UE and includes receiving a scheduled resource and a number of repetitions in the PUSCH transmission, receiving an indication of a procedure to employ when one-symbol repetitions occur, performing a listen-before-talk procedure to acquire the PUSCH, continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition type B, and performing an additional listen-before-talk procedure in a time interval of the one-symbol repetitions when the one-symbol repetitions occur and based on the indication.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method of enhancing the performance of PUSCH repetition Type B for repeated transmissions in Physical Uplink Shared Channel (PUSCH) transmissions from a User Equipment (UE) to a base station (gNB) in a wireless communication system, for licensed and unlicensed spectrum for Ultra-Reliable and Low-Latency Communication (URLLC) with stringent requirements on latency and reliability. BACKGROUND

[0002] Wireless communication systems such as those defined by third-generation (3G) mobile telephone standards and technologies are well known. Such 3G standards and technologies have been developed by the Third Generation Partnership Project (3GPP) (RTM). Third generation wireless communication has evolved to support macro cellular mobile telephony. Communication systems and networks have developed towards broadband and mobile systems.

[0003] In cellular wireless communication systems, User Equipment (UE) connects to a Radio Access Network (RAN) over a wireless link. The RAN comprises a set of base stations which provide the wireless link to UEs located in cells of the base stations, and an interface to a Core Network (CN) which provides overall network control. It will be appreciated that the RAN and CN each perform their own respective functions in relation to the overall network. For convenience, the term cellular network will be used to refer to the combined RAN & CN, and it will be understood that this term is used to refer to the respective systems for performing the disclosed functionality.

[0004] The Third Generation Partnership Project developed the so-called Long Term Evolution (LTE) system, i.e. the Evolved Universal Mobile Telecommunication System Territorial Radio Access Network (E-UTRAN), for mobile access networks, where one or more macro cells are supported by base stations called eNodeBs or eNBs (Evolved Node Bs). More recently, LTE is further evolving towards the so-called 5G or NR (New Radio) system, where one or more cells are supported by base stations called gNB. NR is proposed to use an Orthogonal Frequency Division Multiplexed (OFDM) physical transmission format.

[0005] The NR protocol aims at providing an option to operate in unlicensed radio bands, called NR-U. When operating in unlicensed radio bands, gNBs and UEs have to contend for physical medium / resource access with other devices. For example, Wi-Fi (RTM), NR-U and LAA can use the same physical resources.

[0006] To share resources, a Listen Before Talk (LBT) protocol is proposed, where a gNB or a UE monitors the available resources and starts a transmission only if there is no collision with another device that has already used the resources. Once the LBT procedure is successful (the resources are "won"), the gNB or the UE will get access to the resources for a maximum Channel Occupancy Time (MCOT), provided there is no transmission interruption for more than a predefined interval, e.g. 16 microseconds.

[0007] A trend in wireless communications is to provide services with lower latency and higher reliability. For example, NR aims at supporting Ultra-reliable and low-latency communication (URLLC), while Massive Machine-Type Communications (mMTC) aims at providing low latency and high reliability for small data packet sizes, typically 32 bytes. A user plane latency of 1 ms is proposed, with a reliability of 99.99999%, and a packet loss rate of 10 -5 or 10 -6 at the physical layer is proposed.

[0008] After a transmitter of a node obtains access to a channel, regulations only allow the node to transmit for a limited duration, MCOT, and for one or more transmissions, the use of COT can be selected, which is equal to or only a fraction of the duration of MCOT. Based on the type of traffic served (e.g. VoIP, video, best effort, or background), to provide differentiation of channel access priority, four LBT priority classes are defined, which have different CWS and MCOT.

[0009] The physical design for URLLC is challenging because two conflicting factors, reliability and latency, must be addressed simultaneously. For URLLC service requirements, the term reliability is generally defined as the probability of success R of transmitting X bits within L seconds, where L is the time taken to transfer a small data packet from the radio protocol layer 2 / 3 SDU ingress point to the radio protocol layer 2 / 3 SDU egress point of the wireless interface at some channel quality Q (e.g. coverage edge). The latency bound L includes transmission latency, processing latency, retransmission latency (if any), and queuing / scheduling latency (including scheduling request and grant reception, if any). Spectrum efficiency should also be considered when attempting to achieve the reliability target.

[0010] With respect to the reliability target for URLLC scenarios, NR defines a general URLLC reliability requirement of 10 -5 for a one packet transmission of 32 bytes. For enhanced URLLC, this URLLC reliability requirement has been updated to 10 -6 . This stringent reliability requirement requires very careful design of the transmit-receive techniques within a very low latency budget (ranging between 0.5 to 1 millisecond).

[0011] Development for the physical design of URLLC to address the reliability and latency factors includes PUCSH enhancements. In uplink (UL) transmissions, one PUSCH transmission instance is not allowed to cross the slot boundary of dynamic grant (DG) and configured grant (CG) PUSCH.

[0012] To avoid transmitting long PUSCH transmissions across slot boundaries, a UE transmits small PUSCH transmissions multiple times in repetitions scheduled by the UL resource grant or radio resource control (RRC) in consecutive available transmission slots. This method is referred to as PUSCH repetition Type A. Using such PUSCH repetitions for one transport block (TB) can reduce the latency and improve the reliability of the PUSCH transmission, where the UE can be configured to transmit the multiple repetitions across consecutive transmission slots without feedback. In the PUSCH repetition Type A method, each slot contains only one TB repetition, and the time domain of the TB repetition is the same in each slot.

[0013] A new method, PUSCH repetition Type B, was developed to address the issue of the time interval between repetitions in the PUSCH repetition Type A method. In PUSCH repetition Type B, the repetitions are made in consecutive mini-slots, so one slot can contain more than one TB repetition. However, the repetitions can be split into smaller repetitions due to the slot boundary, the presence of DL symbols, the presence of symbols in the invalid pattern.

[0014] The use of PUSCH includes dynamic grant (DG) and configured grant (CG) of PUSCH resources. CG is configured with two types. In Type 1 CG, RRC signaling indicates full time domain resource allocation, including periodicity, offset, starting symbol, PUSCH transmission length, and repK of K repetitions on K slots / sub-slots, without any layer 1 signaling as downlink control information (DCI). For Type 2 CG, only periodicity and repK are given by RRC signaling. Other time domain resource allocation parameters are provided by DCI activation scrambled with CS-RNTI.

[0015] In unlicensed spectrum usage, there is a channel access procedure. The transmitter of a UE needs to perform a listen-before-talk (LBT) procedure to check the availability of the channel before transmission. In UL DG transmission, the UE can access the channel according to Type 1 or Type 2 UL channel access defined by the UL resource grant.

[0016] In Type 1 UL channel access, the UE senses the energy of the channel for a defer time period. The length of the defer time depends on the channel access priority, as shown in Figure 1 16 + 9*m p(microseconds). If the energy detection is below the threshold, the channel is considered idle during the defer duration, otherwise the channel is busy. After detecting an idle channel for the defer duration, the UE detects the channel for additional slots. The number of additional slots (N) is randomly selected from a uniform distribution between 0 and CWp, whose value depends on the channel priority access class, again as shown in Figure 1 The UE decrements N by 1 each time it listens for an idle channel in an additional slot. When N reaches 0, the UE transmits data.

[0017] In Type 2 UL channel access, the UE transmits data immediately after sensing that the channel obtained by the gNB is idle for a duration of 16 microseconds (Type 2B) or 25 microseconds (Type 2A). If the interval between two UL transmissions is less than 16 microseconds, the client does not have to perform an LBT procedure before transmitting the second UL transmission.

[0018] UL transmission of a TB supports multiple repetitions of the TB to meet the stringent URLLC requirements on reliability. The time domain resource assignment (TDRA) field in the DCI indicates the resources for the first “nominal” repetition of the TB. The time domain resources for the remaining repetitions of the TB are derived based at least on the UL / DL direction of the resources and symbols used for the first TB repetition. The dynamic indication of the number of DG repetitions is jointly encoded with the start and length indicator value (SLIV), which indicates the starting symbol and the length of the PUSCH transmission, by adding an additional column in the TDRA table for indicating the number of repetitions in the TDRA table for DCI formats 0_1 and 0_2. The maximum TDRA table size is increased to 64. For CG PUSCH transmission, if the number of repetitions is not included in the TDRA table, it is provided by the RRC parameter repK.

[0019] The number of PUSCH repetitions indicates the “nominal” number of repetitions. The actual number of repetitions can be greater than the nominal number. If a nominal repetition encounters a slot boundary or the presence of a DL symbol in the time division duplex (TDD) configuration, this repetition is split into multiple actual repetitions.

[0020] In unlicensed spectrum, interruption of UL transmission of a TB repetition results in LBT overhead. Figure 2Two cases of UL transmission in TDD configuration are shown. In both cases, the UE is scheduled by gNB to transmit four nominal TB repetitions using PUSCH repetition Type B (DG or CG transmission). The time window of valid symbols for transmission is K x L, where K is the four nominal repetitions and L is the length of the nominal repetition. Before the transmission, the UE has to perform LBT Type 1 procedure to acquire the channel and is allowed to use the channel for the Channel Occupancy Time (COT) duration.

[0021] In Figure 2 Scenario 1, there are four consecutive UL sub-slots, so the UE can transmit all four repetitions uninterruptedly after successfully performing the LBT Type 1 procedure. However, in Scenario 2, the UL transmission is interrupted due to the presence of a DL symbol in the middle of the second repetition. The UE cannot transmit UL data during the DL transmission occasion, so the second repetition is split into two actual repetitions. For SCS from 15 kHz to 120 kHz and 2, 4, 7 symbols sub-slot, the time length of a DL sub-slot is greater than 16 microseconds. In some cases, the DL symbols are pre-configured in a semi-static way. If the gNB has no DL data to transmit on those semi-static DL symbols, there will be a gap between the two UL bursts. When the gap between the two UL transmissions is greater than 16 microseconds, due to the presence of empty semi-static DL symbols, the UE has to perform an additional LBT procedure, i.e. LBT Type 2 procedure, to continue transmitting the remaining repetitions. This COT is initiated by the LBT Type 1 procedure before the first repetition. The additional LBT Type 2 procedure consumes at least 25 microseconds. This LBT procedure time can exceed 25 microseconds if the channel is busy. The time window K x L is fixed, so the increase of the LBT procedure time reduces the time for data transmission. The UE transmits less data than configured in the repetitions, which results in reduced reliability. In Figure 2 Scenario 2, the UL repetitions have to be scheduled in the UL transmission resources, segmented by DL sub-slots, to meet the 1 ms URLLC latency budget, the UL repetition transmission cannot wait for the next available four consecutive UL sub-slots to transmit all repetitions.

[0022] In licensed spectrum, the presence of DL symbols in the middle of PUSCH repetition also reduces the number of valid symbols that the UE can use for PUSCH transmission in the time window K x L. This affects the reliability of the UL transmission of TB.

[0023] The gap in the UL TB repetition transmission is also due to encountering the slot boundary, even if the nominal repetition is split into two actual repetitions. In Figure 3In scenario 2 of FIG. 2, two repetitions of a TB are scheduled using PUSCH repetition Type B. Each repetition has four symbols. After the first repetition, the second repetition is segmented by a slot boundary between slot 1 and slot 2. There is one symbol of the second repetition in slot 1 and 3 symbols in slot 2. However, a repetition with a single symbol is not transmitted. Therefore, the UE does not transmit a repetition in the last symbol of slot 1, so that symbol is empty. The UE only transmits the second repetition starting from the first symbol of slot 2. This creates a gap of one symbol between the two repetitions. For SCS from 15 kHz to 60 kHz, the length of a symbol is greater than 16 microseconds. Therefore, in unlicensed spectrum, at least a 25-microsecond LBT procedure needs to be performed before the transmission of the second repetition. This results in LBT overhead and reduces the time interval in which the UE can transmit the second repetition. SUMMARY

[0024] The summary is provided to introduce some concepts in a simplified form, which will be further described in the detailed description below. The summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0025] A method of enhancing performance of a physical uplink shared channel (PUSCH) repetition Type B is provided for repetitions in a PUSCH transmission from a user equipment (UE) to a base station of a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a listen-before-talk procedure to be employed upon interruption of the PUSCH transmission; the UE receiving the scheduled resources in the PUSCH transmission and the number of repetitions; the UE receiving the indication of the listen-before-talk procedure to be employed upon interruption of the PUSCH transmission; the UE performing a listen-before-talk procedure to acquire the PUSCH; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; wherein the indication of a listen-before-talk procedure to be employed upon interruption of the PUSCH transmission causes the UE to continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B without performing an additional listen-before-talk procedure when an interruption in transmission of the repetitions in the PUSCH transmission is encountered.

[0026] The method can be used for PUSCH transmissions of ultra-reliable, low latency communications (URLLC) with high priority.

[0027] The indication of a listen-before-talk procedure to be employed upon interruption of the PUSCH transmission comprises an explicit signal for the indication.

[0028] The explicit signal for the indication comprises any of a value of an additional bit in a downlink control information, DCI, transmitted by the base station to the UE, an additional parameter in radio resource control, RRC, signaling.

[0029] The indication to employ the listen-before-talk procedure at interruption of the PUSCH transmission comprises an implicit signal for the indication.

[0030] The implicit signal for the indication comprises a high value of a priority index for the PUSCH transmission.

[0031] The method can be used when the interruption of the repeated transmissions in the PUSCH transmission is due to the presence of DL symbols during the repeated transmissions, and the indication of the listen-before-talk procedure employed at interruption of the PUSCH transmission due to the presence of the DL symbols comprises an explicit signal comprising any of a value of an additional bit in a DCI transmitted by the base station to the UE, an additional parameter in RRC signaling.

[0032] The method can be used when the interruption of the repeated transmissions in the PUSCH transmission is due to the presence of invalid symbols during the repeated transmissions, and the indication of the listen-before-talk procedure employed at interruption of the PUSCH transmission due to the presence of the invalid symbols comprises an explicit signal comprising any of a value of an additional bit in a DCI transmitted by the base station to the UE, an additional parameter in RRC signaling.

[0033] The method can be used when the interruption of the repeated transmissions in the PUSCH transmission is due to a slot boundary resulting in one-symbol repetition, and the indication of the listen-before-talk procedure employed at interruption of the PUSCH transmission due to the slot boundary resulting in one-symbol repetition comprises an explicit signal comprising any of a value of an additional bit in a DCI transmitted by the base station to the UE, an additional parameter in RRC signaling.

[0034] The indication to employ the listen-before-talk procedure at interruption of the PUSCH transmission comprises an explicit signal for the indication. The explicit signal comprises a value of a first additional bit in a DCI for interruption due to presence of any of DL symbols and invalid symbols and a value of a second additional bit in a DCI for interruption due to a slot boundary resulting in one-symbol repetition.

[0035] The indication to employ a listen-before-talk procedure at an interruption of the PUSCH transmission comprises an explicit signal for the indication. The explicit signal comprises a first additional parameter in RRC signaling for an interruption caused by the presence of any DL symbol and invalid symbol and a second additional parameter in RRC signaling for an interruption caused by a slot boundary resulting in one symbol repetition.

[0036] A method of enhancing PUSCH repetition Type B performance is provided for repetition in a PUSCH transmission from a UE to a base station of a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a transmission procedure to employ when one symbol repetition occurs; the UE receiving the scheduled resources in the PUSCH transmission and the number of repetitions; the UE receiving the indication of the transmission procedure to employ when the one symbol repetition occurs; the UE performing a listen-before-talk procedure to acquire the PUSCH; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; the indication of the transmission procedure to employ when the one symbol repetition occurs causing the UE to continue transmission of the one symbol repetition and further repetitions in the PUSCH transmission using the PUSCH repetition Type B when the one symbol repetition occurs.

[0037] The method can be used for PUSCH transmission of Ultra-Reliable, Low-Latency Communication (URLLC) with high priority.

[0038] The one symbol repetition contains a DMRS.

[0039] The indication of the transmission procedure to employ when the one symbol repetition occurs comprises an explicit signal for the indication.

[0040] The explicit signal for the indication comprises any of a value of an additional bit in a downlink control information, DCI, transmitted by the base station to the UE, an additional parameter in radio resource control, RRC, signaling.

[0041] The indication of the transmission procedure to employ when the one symbol repetition occurs comprises an implicit signal for the indication, the implicit signal comprising a high value of a priority index for the PUSCH transmission.

[0042] A method of enhancing performance of a physical uplink shared channel (PUSCH) repetition Type B is provided for repetitions in a PUSCH transmission of a UE to a base station in a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a procedure to be employed when one-symbol repetition occurs; the UE receiving the scheduled resources in the PUSCH transmission and the number of repetitions; the UE receiving the indication of the procedure to be employed when the one-symbol repetition occurs; the UE performing a listen-before-talk procedure to acquire the PUSCH; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; wherein when the one-symbol repetition occurs, the indication of the procedure to be employed when the one-symbol repetition occurs causes the UE to perform an additional listen-before-talk procedure within a time interval of the one-symbol repetition.

[0043] The time interval of the one-symbol repetition and the additional listen-before-talk procedure is equal to a time interval of one OFDM symbol. The time interval of the additional listen-before-talk procedure is configured to fit within the time interval of the one OFDM symbol.

[0044] A method of enhancing performance of a PUSCH repetition Type B is provided for repetitions in a PUSCH transmission of a UE to a base station in a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a transmission procedure to be employed when interruption of the PUSCH transmission occurs; the UE receiving the scheduled resources in the PUSCH transmission, the number of repetitions, and DL symbols; the UE receiving the indication of the transmission procedure to be employed when interruption of the PUSCH transmission occurs; the UE performing a listen-before-talk procedure to acquire the PUSCH in unlicensed spectrum; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; when encountering interruption of transmission of the repetitions in the PUSCH transmission, the indication of the transmission procedure to be employed when interruption of the PUSCH transmission occurs causes the UE to switch at least some DL symbols to UL symbols and continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B through UL symbols.

[0045] When the base station has no DL data to transmit through the DL symbols, the indication of the transmission procedure to be employed when interruption of the PUSCH transmission occurs causes the UE to switch all DL symbols to UL symbols.

[0046] The indication of the transmission procedure to employ upon interruption of the PUSCH transmission causes the UE to switch all DL symbols to UL symbols when the base station has DL data to transmit over the DL symbols and the repeated UL data has a higher priority than the DL data.

[0047] For DG transmissions, the indication of the transmission procedure to employ upon interruption of the PUSCH transmission comprises any one of a dynamic SFI signal sent to the UE, a value of an additional bit of a DCI for UL resource grant, a high value of a priority index for the PUSCH transmission.

[0048] For CG transmissions, the indication of the transmission procedure to employ upon interruption of the PUSCH transmission comprises a high value of the priority index of the PUSCH transmission, any one of a DCI format 20.

[0049] A method of enhancing PUSCH repetition Type B performance for repetitions in a PUSCH transmission from a UE to a base station in a wireless communication network is provided, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a transmission procedure to employ upon interruption of the PUSCH transmission; the UE receiving the scheduled resources and the number of repetitions in the PUSCH transmission; the UE receiving the indication of the transmission procedure to employ upon interruption of the PUSCH transmission; the UE performing a listen-before-talk procedure to acquire the PUSCH (in unlicensed spectrum); and the UE continuing to transmit the repetitions in the PUSCH transmission using the PUSCH repetition Type B; when an interruption in transmission of the repetitions in the PUSCH transmission is encountered, the indication of the transmission procedure to employ upon interruption of the PUSCH transmission causes the UE to continue to transmit the repetitions in the PUSCH transmission using the PUSCH repetition Type B over semi-static flexible symbols in the scheduled resources.

[0050] A UE configured to perform any of the above methods is provided.

[0051] A non-transitory computer readable medium storing instructions which, when executed by a computer, perform any of the above methods is provided. The non-transitory computer readable medium can comprise at least one of the following group: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read-Only Memory, a Programmable Read-Only Memory, an Erasable Programmable Read-Only Memory, an EPROM, an Electrically Erasable Programmable Read-Only Memory, and a Flash memory. BRIEF DESCRIPTION OF DRAWINGS

[0052] Further details, aspects and embodiments of the application will be described, by way of example only, with reference to the drawings. Components in the drawings are shown schematically and not necessarily to scale. Like reference numerals have been included in corresponding drawings to facilitate understanding.

[0053] Figure 1 Channel access priority for UL is shown.

[0054] Figure 2 Two cases of UL transmission in TDD configuration are shown.

[0055] Figure 3 UL repetition transmission interruption due to slot boundary is shown.

[0056] Figure 4 A schematic diagram showing three base stations forming a cellular network is shown.

[0057] Figure 5 PUSCH transmission interruption in repetition transmission caused by a DL symbol is shown.

[0058] Figure 6 PUSCH transmission interruption in repetition transmission caused by a slot boundary resulting in one symbol repetition is shown.

[0059] Figure 7 Transmission of one symbol repetition is shown.

[0060] Figure 8 Switching from a DL symbol to an UL symbol for repetition transmission in PUSCH transmission is shown. DETAILED DESCRIPTION

[0061] Those skilled in the art will recognize and appreciate that the details of the described examples are merely illustrative and that the teachings set forth herein are applicable to a variety of alternative settings.

[0062] Figure 4 A schematic diagram showing three base stations (e.g. eNBs or gNBs depending on the particular cellular standard and terminology) forming a cellular network is shown. Typically, each base station will be deployed by one cellular network operator to provide geographical coverage for UEs in that area. The base stations form a Radio Area Network (RAN). Each base station provides wireless coverage for UEs in its area or cell. The base stations are interconnected by means of an X2 interface and connected to a core network by means of an S1 interface. It will be appreciated that only basic details are shown for the purpose of illustrating key features of a cellular network.

[0063] Each base station includes hardware and software for implementing RAN functionality, including communication with the core network and other base stations, control and data signal transmission between the core network and UEs, and maintaining wireless communication with UEs associated with each base station. The core network includes hardware and software for implementing network functionality, such as overall network management and control, and routing of calls and data.

[0064] According to a first embodiment of the present application, a method for enhancing performance of Physical Uplink Shared Channel (PUSCH) repetition Type B is provided for repetition in PUSCH transmission from a UE to a base station in a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a Listen Before Talk (LBT) procedure to be employed upon interruption of the PUSCH transmission; the UE receiving the scheduled resources in the PUSCH transmission and the number of repetitions; the UE receiving the indication of the LBT procedure to be employed upon interruption of the PUSCH transmission; the UE performing a LBT procedure to acquire the PUSCH; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; wherein the indication of a LBT procedure to be employed upon interruption of the PUSCH transmission causes the UE to continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B without performing an additional LBT procedure when an interruption in transmission of the repetitions in the PUSCH transmission is encountered.

[0065] The method is for PUSCH transmission with high priority, such as URLLC.

[0066] The indication of a LBT procedure to be employed upon interruption of the PUSCH transmission comprises an explicit signal for the indication.

[0067] The explicit signal for the indication comprises a value of an additional bit in a Downlink Control Information (DCI) sent by the base station to the UE. In dynamic grant (DG) of PUSCH resources, the additional bit is added to the DCI for UL resource grant. In configured grant (CG) Type 2 of PUSCH resources, the additional bit is added to the DCI to activate a CG configuration.

[0068] Alternatively, the explicit signal for the indication comprises an additional parameter in Radio Resource Control (RRC) signaling. This allows the design of DCI to remain unchanged. The method embodiment is applicable to DG and CG transmission, especially CG Type 1 transmission, configured by RRC without any DCI.

[0069] In an alternative embodiment of the method, the indication of a LBT procedure to be employed upon interruption of the PUSCH transmission comprises an implicit signal for the indication.

[0070] The implicit signal for indication includes a high value of priority index for PUSCH transmission. For DG transmission, the high value of priority index for PUSCH transmission is indicated by a 1-bit priority field in the DCI for UL resource grant. For CG transmission, the high value of priority index for PUSCH transmission is indicated by a RRC parameter or an activation DCI.

[0071] The method is used when the interruption of repeated transmission in PUSCH transmission is caused by the presence of DL symbols during the repeated transmission.

[0072] The explicit signal for indication of LBT procedure employed when PUSCH transmission is interrupted due to the presence of DL symbols includes the value of an additional bit in the downlink control information (DCI) sent by the gNB to the UE. Alternatively, the explicit signal for indication of LBT procedure employed when PUSCH transmission is interrupted due to the presence of DL symbols includes an additional parameter in the radio resource control (RRC) signaling.

[0073] Currently, in TDD configuration, DL symbols can be pre-configured in a semi-static manner. If the gNB has no DL data to transmit on those semi-static DL symbols, there will be a transmission interruption or gap between the repeated transmission before the empty DL symbol and the repeated transmission after the empty DL symbol. Due to the empty semi-static DL symbol, one repetition can be split into two repetitions. If the transmission gap is larger than 16 microseconds, the UE has to perform an additional LBT procedure before continuing the transmission repetition. The 16 microseconds gap is the value defined in the current standard. If the future standard changes the gap value, the method is still applicable.

[0074] The present invention sends an indication from the gNB to the UE of the LBT procedure employed when PUSCH transmission is interrupted. The LBT procedure enables the UE to continue the transmission repetition after the transmission interruption due to the presence of DL symbols without performing an additional LBT procedure. This is in Figure 5 Scenario 2 of the present invention is shown when the repeated transmission is split into two repeated transmissions due to the empty semi-static DL symbol, the UE continues the transmission of Rep 3 without performing the LBT procedure.

[0075] The method is used when the interruption of repeated transmission in PUSCH transmission is caused by the presence of invalid symbols during the repeated transmission.

[0076] The explicit signal for indication of LBT procedure employed when PUSCH transmission is interrupted due to the presence of invalid symbols includes the value of an additional bit in the downlink control information (DCI) sent by the gNB to the UE. Alternatively, the explicit signal for indication of LBT procedure employed when PUSCH transmission is interrupted due to the presence of invalid symbols includes an additional parameter in the radio resource control (RRC) signaling.

[0077] The presence of invalid symbols is indicated by the InvalidSymbolPattern parameter. The InvalidSymbolPattern parameter can be an RRC parameter and / or an activation DCI parameter. The configuration and activation of the InvalidSymbolPattern parameter results in interruption of PUSCH transmission, especially for CG transmission, as the gNB cannot predict the arrival of data to the UE for the entire active time of the CG configuration and cannot avoid the collision between invalid symbols and UL PUSCH transmission.

[0078] The principle of this method can be extended to DL transmission in TDD configuration. If a DL transmission with high priority is split by an UL symbol, the gNB performs an LBT procedure, and before resuming the DL transmission, the gNB does not perform an additional LBT procedure if the UL symbol is empty.

[0079] This method is used when the interruption of a repetition transmission in PUSCH transmission is caused by a slot boundary that generates one-symbol repetition.

[0080] The explicit signal for indicating the LBT procedure when the interruption of PUSCH transmission is caused by a slot boundary that generates one-symbol repetition includes the value of an additional bit in the downlink control information (DCI) sent by the gNB to the UE. This can be applied to DG transmission and CG Type 2 transmission. Alternatively, the explicit signal for indicating the LBT procedure when the interruption of PUSCH transmission is caused by a slot boundary that generates one-symbol repetition includes an additional parameter in the radio resource control (RRC) signaling. This can be applied to DG transmission and CG Type 1 and Type 2 transmission.

[0081] Currently, if one repetition is split into two repetitions by a slot boundary and one repetition has only one symbol when the transmission repetition, the one-symbol repetition is not transmitted. This causes interruption in UL PUSCH transmission and requires an additional LBT procedure to be performed after the interruption. In turn, this causes delay in unlicensed spectrum.

[0082] When the gNB schedules resources and the number of repetitions to the UE, the gNB is aware of the generation of one-symbol repetition by the position of the repetition resource relative to the slot boundary. Therefore, the gNB knows the interruption of a repetition transmission in PUSCH transmission and sends the indication of the LBT procedure used when the PUSCH transmission is interrupted to the UE. This results in the UE continuing the transmission repetition after the interruption of transmission caused by a slot boundary that generates one-symbol repetition without performing an additional LBT procedure. This is illustrated in Figure 6 .

[0083] Alternatively, the explicit signal for indicating the LBT procedure employed at the interruption of PUSCH transmission due to the presence of any DL symbol, the presence of invalid symbol, slot boundary resulting in one symbol repetition comprises the value of an additional bit in the downlink control information (DCI) sent by the gNB to the UE. Alternatively, the explicit signal for indicating the LBT procedure employed at the interruption of PUSCH transmission due to any of the presence of DL symbol, the presence of invalid symbol, slot boundary resulting in one symbol repetition comprises an additional parameter in the radio resource control (RRC) signaling.

[0084] Alternatively, the explicit signal for indicating the LBT procedure employed at the interruption of PUSCH transmission comprises an explicit signal for said indication. The explicit signal comprises the value of a first additional bit in the DCI for the interruption due to the presence of any DL symbol and invalid symbol and the value of a second additional bit in the DCI for the interruption due to the slot boundary resulting in one symbol repetition sent by the gNB to the UE.

[0085] Alternatively, the explicit signal for indicating the LBT procedure employed at the interruption of PUSCH transmission comprises a first additional parameter in the RRC signaling for the interruption due to the presence of any DL symbol and invalid symbol and a second additional parameter in the RRC signaling for the interruption due to the slot boundary resulting in one symbol repetition sent by the gNB to the UE.

[0086] In the first embodiment of the invention, no additional LBT procedure is required to be performed, i.e. skipped, after the interruption of repeated transmission in PUSCH due to any DL symbol or invalid symbol or slot boundary. This happens when the PUSCH repetition carries URLLC transport block with strict reliability and delay requirements. The LBT skipping indication signal is indicated by the gNB to the UE by using an additional bit in the DCI, RRC or association with the priority index in the DCI. This embodiment is most suitable for unlicensed spectrum.

[0087] According to a second embodiment of the present application, there is provided a method of enhancing performance of PUSCH repetition Type B for repetitions in a PUSCH transmission from a UE to a base station in a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a transmission procedure to be employed when one-symbol repetitions occur; the UE receiving the scheduled resources in the PUSCH transmission and the number of repetitions; the UE receiving the indication of the transmission procedure to be employed when the one-symbol repetitions occur; the UE performing a listen-before-talk procedure to acquire the PUSCH; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; when the one-symbol repetitions occur, the indication of the transmission procedure to be employed when the one-symbol repetitions occur causes the UE to continue transmission of the one-symbol repetitions and further repetitions in the PUSCH transmission using the PUSCH repetition Type B.

[0088] Transmission of repetitions in a PUSCH transmission is therefore avoided from being interrupted by the occurrence of one-symbol repetitions. The UE transmits one-symbol repetitions, so transmission of repetitions in a PUSCH transmission is continuous. There is no need to perform an LBT procedure after the occurrence of one-symbol repetitions. This is shown in Figure 7 Transmission of one-symbol repetitions by the UE preserves PUSCH resources, so the UE can immediately transmit further repetitions in the PUSCH transmission.

[0089] The method of the second aspect of the present application is for PUSCH transmissions with high priority, such as URLLC.

[0090] One-symbol repetitions contain a signal to ensure continuous transmission between repetitions. One of the signals that can be used in one-symbol repetitions is a DMRS. A DMRS one-symbol repetition is not considered in the calculation of the RV sequence of repetitions.

[0091] Transmission of a DMRS one-symbol repetition provides the UE with an opportunity to perform channel estimation and improves the performance of high-priority UL transmissions. Since a DMRS one-symbol repetition does not contain data, it is not considered in the calculation of the RV sequence of repetitions. In other words, a DMRS one-symbol repetition is transmitted but not considered to be an actual repetition.

[0092] The indication of the transmission procedure to be employed when one-symbol repetitions occur comprises an explicit signal for the indication.

[0093] The explicit signal for the indication comprises a value of an additional bit in downlink control information (DCI) sent by the gNB to the UE. Alternatively, the explicit signal for the indication comprises an additional parameter in radio resource control (RRC) signalling.

[0094] In UL DG transmission, the indication includes a value of an additional bit in downlink control information (DCI) for UL resource grant. The value of the additional bit causes the UE to transmit a signal such as DMRS in one-symbol repetition. In UL Type 1 CG transmission, the indication includes an additional parameter in radio resource control (RRC) signaling. The value of the additional parameter causes the UE to transmit a signal such as DMRS in one-symbol repetition. In UL Type 2 CG transmission, the indication includes an additional bit in activation downlink control information (DCI). The value of the additional bit causes the UE to transmit a signal such as DMRS in one-symbol repetition.

[0095] In one alternative embodiment of the method, the indication transmission procedure employed when one-symbol repetition occurs includes an implicit signal for the indication.

[0096] The implicit signal for the indication includes a high value of a priority index for PUSCH transmission. For DG transmission, the high value of the priority index for PUSCH transmission is indicated by a 1-bit priority field in DCI for UL resource grant. For CG transmission, the high value of the priority index for PUSCH transmission is indicated by an RRC parameter or activation DCI.

[0097] According to a third embodiment of the present application, there is provided a method of enhancing performance of physical uplink shared channel (PUSCH) repetition Type B for repetition in PUSCH transmission from a user equipment (UE) to a base station in a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a procedure employed when one-symbol repetition occurs; the UE receiving the scheduled resources in the PUSCH transmission and the number of repetitions; the UE receiving the indication of the procedure employed when the one-symbol repetition occurs; the UE performing a listen-before-talk procedure to acquire the PUSCH; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; wherein when the one-symbol repetition occurs, the indication of the procedure employed when the one-symbol repetition occurs causes the UE to perform an additional listen-before-talk procedure within a time interval of the one-symbol repetition.

[0098] The time interval of the one-symbol repetition and the additional listen-before-talk procedure is equal to a time interval of one OFDM symbol. A time between an end of the additional LBT procedure and a start of a next repetition transmission is less than 16 microseconds. The time interval of the additional listen-before-talk procedure is configured to fit the time interval of the one OFDM symbol. A time interval of the additional LBT procedure is a function of sub-carrier spacing (SCS) pre-configured between the gNB and the UE.

[0099] According to a fourth embodiment of the present application, there is provided a method of enhancing PUSCH repetition Type B performance for repetition in a PUSCH transmission of a UE to a base station in a wireless communication network, comprising: the base station scheduling a number of resource repetitions and DL symbols in the PUSCH transmission; the base station establishing an indication of a transmission procedure to be employed upon interruption of the PUSCH transmission; the UE receiving the scheduled resources, the number of repetitions and the DL symbols in the PUSCH transmission; the UE receiving the indication of the transmission procedure to be employed upon interruption of the PUSCH transmission; the UE performing a listen-before-talk procedure to acquire the PUSCH in unlicensed spectrum; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; when an interruption of transmission of the repetitions in the PUSCH transmission is encountered, the indication of the transmission procedure to be employed upon interruption of the PUSCH transmission causes the UE to switch at least some DL symbols to UL symbols and to continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B through UL symbols.

[0100] Currently, in TDD configurations, DL symbols can be configured in a semi-static manner so that the gNB can transmit DL data (using PDCCH, PDSCH, SSB). Due to time constraints, the gNB can also schedule PUSCH transmissions using repetitions segmented by semi-static DL symbols. This results in interruptions of transmission of repetitions in the segmented PUSCH transmission of PUSCH repetitions. This happens even if the gNB has no DL data to transmit using the semi-static DL symbols in the PUSCH transmission. This is in Figure 8 Scenario 1. The DL symbols are pre-scheduled in a semi-static manner, so the gNB does not know if it has DL data to transmit using the semi-static DL symbols.

[0101] When the gNB has no DL data to transmit through the DL symbols, the indication of the transmission procedure to be employed upon interruption of the PUSCH transmission causes the UE to switch all DL symbols to UL symbols.

[0102] When the gNB schedules repetitions in a PUSCH transmission, if it realizes that it has no DL data to transmit through the DL symbols, it causes the UE to switch all (empty) semi-static DL symbols to UL symbols. This is shown in Figure 8In scenario 2 of FIG. 2, it shows a transmission in unlicensed spectrum. The DL-to-UL symbol switching has two benefits: 1) the UE can transmit the PUSCH repetition without interruption or segmentation, thus ensuring K x L valid symbols for the UL transmission, and 2) no additional LBT procedure is performed due to the interruption. The empty semi-static DL symbol-to-UL symbol switching also applies to the PUSCH repetition in licensed spectrum, so that the UE can send all repetitions in the configured manner in the time window to guarantee reliability.

[0103] When the gNB has DL data to transmit through the DL symbols and the repeated UL data has higher priority than the DL data, the transmission procedure indication adopted at the interruption of the PUSCH transmission is for the UE to switch all the DL symbols to UL symbols.

[0104] When the gNB has DL data to transmit through the semi-static DL symbols, if the UL data has higher priority than the DL data, the gNB causes the UE to switch the semi-static DL symbols to UL symbols and delays the DL data transmission to the next available occasion so that the UE can transmit the continuous high-priority UL data.

[0105] The DL-symbol-to-UL-symbol switching applies to both DG and CG transmissions.

[0106] For DG transmission, the transmission procedure indication adopted at the interruption of the PUSCH transmission includes a dynamic SFI signal sent to the UE. The dynamic SFI signal is a DCI format 2_0.

[0107] Alternatively, for DG transmission, the indication of the transmission procedure adopted at the interruption of the PUSCH transmission includes a value of an additional bit of the DCI for the UL resource grant.

[0108] Alternatively, for DG transmission, the indication of the transmission procedure adopted at the interruption of the PUSCH transmission includes a high value of a priority index of the PUSCH transmission. For DG transmission, the high value of the priority index of the PUSCH transmission is indicated by a 1-bit priority field in the DCI for the UL resource grant. For CG transmission, the high value of the priority index of the PUSCH transmission is indicated by an RRC parameter or an activation DCI.

[0109] For DG transmission, the high value of the priority index of the PUSCH transmission is indicated by a 1-bit priority field in the DCI for the UL resource grant.

[0110] For CG transmission, the high value of the priority index of the PUSCH transmission is indicated by an RRC parameter or an activation DCI.

[0111] For CG transmission, the indication of transmission procedure to be adopted at the interruption of PUSCH transmission includes a dynamic SFI signal. The dynamic SFI signal can be a DCI format 2_0.

[0112] The gNB can send the DCI format 2_0 periodically. The periodicity of sending the DCI format 2_0 depends on the priority of the CG configuration, the rate of UL data arrival to the UE using the configuration, and the rate of DL data arrival to the gNB.

[0113] This method can be extended to switch semi-static UL symbols to DL symbols. Then, the gNB can switch semi-static UL symbols to DL symbols for DL transmission. This is useful when the gNB has a high rate of URLLC DL data arrival and needs to use the switched symbols to meet the URLLC requirement of DL transmission. The gNB sends a dynamic SFI signal to inform the UE to switch semi-static UL symbols to DL symbols so that the UE decodes the DL transmission in these symbols instead of transmitting UL data.

[0114] In this aspect of the invention, a dynamic signal (DCI, additional bits in RRC or association with priority index in DCI / RRC) from the gNB is used to switch DL symbols in the middle of URLLC PUSCH repetition that causes interruption of the repetition transmission to UL symbols. The interruption of URLLC PUSCH repetition is eliminated, thus also the LBT overhead in unlicensed spectrum to reduce latency. Furthermore, in both licensed and unlicensed spectrum, the UE can be guaranteed to meet the reliability requirement with the configured repetition transmission in the scheduled time window.

[0115] According to a fifth embodiment of the invention, there is provided a method of enhancing PUSCH repetition Type B performance for repetition in a UE-to-base station PUSCH transmission of a wireless communication network, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a transmission procedure to be adopted at an interruption of the PUSCH transmission; the UE receiving the scheduled resources and the number of repetitions in the PUSCH transmission; the UE receiving the indication of the transmission procedure to be adopted at the interruption of the PUSCH transmission; the UE performing a listen-before-talk procedure to acquire the PUSCH (in unlicensed spectrum); and the UE continuing to transmit the repetitions in the PUSCH transmission using the PUSCH repetition Type B; when encountering an interruption of transmission of the repetitions in the PUSCH transmission, the indication of the transmission procedure to be adopted at the interruption of the PUSCH transmission causing the UE to continue to transmit the repetitions in the PUSCH transmission using the PUSCH repetition Type B through semi-static flexible symbols in the scheduled resources.

[0116] For CG transmissions in licensed and unlicensed spectrum, if dynamic SFI is configured but the UE fails to decode the DCI format 2_0 indicating the SFI due to channel conditions, the UE uses the semi-static flexible symbols in the scheduled resources as UL symbols to transmit the repetition without any interruption. In other words, the repetition is not split around the semi-static flexible symbols or dropped due to collision with semi-static flexible symbols. Therefore, in unlicensed spectrum, no additional LBT procedure needs to be performed during PUSCH repetition transmission. Also in licensed and unlicensed spectrum, the configured number of repetitions is ensured.

[0117] Various embodiments of the present invention have the following advantages: reduce LBT latency, increase time for UE to transmit data, improve UL transmission reliability, eliminate gap between repetitions, avoid dropping CG PUSCH repetition in case of collision with semi-static flexible symbols.

[0118] Although not shown in detail, any device or apparatus forming part of a network can comprise at least a processor, a memory, and a communication interface, wherein the processor, the memory, and the communication interface are configured to perform any aspect of the present invention. Further options and choices are described below.

[0119] The signal processing functionality of embodiments of the present invention, in particular of gNB and UE, can be implemented using a computing system or architecture known to those of skill in the relevant art. A computing system, such as a desktop, laptop or notebook computer, hand-held computing device (PDA, cell phone, palmtop, etc.), mainframe, server, client, or any other type of special or general purpose computing device, can be desirable or suitable for implementing the present invention for a given application or environment. The computing system can include one or more processors, which can be implemented using a general or special purpose processing engine such as a microprocessor, microcontroller or other control module.

[0120] The computing system can further include a main memory, such as random access memory (RAM) or other dynamic storage devices, for storing information and instructions to be executed by the processor. Such main memory also can be for storing temporary variables or other intermediate information during execution of instructions to be executed by the processor. The computing system likewise can include a read only memory (ROM) or other static storage device for storing static information and instructions for the processor.

[0121] The computing system can also include an information storage system, which can include, for example, a memory drive and a removable storage interface. The memory drive can include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a Compact Disk (CD) or Digital Video Drive (DVD) (R or RW) drive, or other removable or fixed media drive. Storage media can include, for example, a hard disk, floppy disk, magnetic tape, optical disk, CD or DVD, or other fixed or removable medium that is read by and written to by the media drive. Storage media can include a computer-readable storage medium, having stored therein particular computer software or data.

[0122] In alternative embodiments, the information storage system can include other similar components for allowing computer programs or other instructions or data to be loaded into the computing system. Such components can include, for example, a removable storage unit and an interface, such as a program cartridge and cartridge interface, a removable memory (for example, a flash memory or other removable memory module) and memory slot, and other removable storage units and interfaces that allow software and data to be transferred from the removable storage unit to the computing system.

[0123] The computing system can also include a communications interface. Such a communications interface can be used to allow software and data to be transferred between the computing system and external devices. Examples of communications interfaces can include a modem, a network interface (such as an Ethernet or other NIC card), a communications port (such as a Universal Serial Bus (USB) port), a PCMCIA slot and card, etc. Software and data transferred via the communications interface are in the form of signals, which can be electronic, electromagnetic, and optical or other signals capable of being received by a communications interface.

[0124] In this document, the terms “computer program product,” “computer-readable medium,” and the like can be used to generally refer to tangible media, such as memory, storage devices, or storage units. These, and other forms of computer-readable media, can store one or more instructions for use by a processor of the computing system to cause the processor to perform a specified operation. Such instructions, generally referred to as “computer program code” (which can be grouped in the form of computer programs or other groupings), when executed, enable the computing system to perform the functions of embodiments of the present application. Note that the code can directly cause a processor to perform specified operations, be compiled to

[0125] The non-transitory computer readable medium can include at least one from among the group consisting of a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a read-only memory, a programmable read-only memory, an erasable memory programmable read-only memory, an EPROM, an electrically erasable programmable read-only memory, and a flash memory. In embodiments where components are implemented using software, the software can be stored in a computer readable medium and loaded into the computing system using, for example, a removable storage drive. The control modules, in this example software instructions or executable computer program code, when executed by a processor in the computer system, cause the processor to perform the functions of the application as described herein.

[0126] Furthermore, the inventive concept can be applied to any circuitry for performing signal processing functions within a network element. It is further envisaged that, for example, a semiconductor manufacturer can employ the inventive concept in the design of a stand-alone device, such as a microcontroller of a digital signal processor (DSP), or an application specific integrated circuit (ASIC), and / or any other sub-system component.

[0127] It will be appreciated that, for clarity, the above description has described embodiments of the application with reference to a single processing logic. However, the inventive concept can equally be implemented by means of a plurality of distinct functional units and processors to provide the signal processing functionality, and as such the reference to a particular functional unit is understood to refer to a suitable means for providing that described functionality, rather than necessarily being a reference to an entity that functions in that manner.

[0128] Aspects of the application can be implemented in any suitable form including hardware, software, firmware or any combination of these. The application can optionally be implemented at least partly as computer software running on one or more data processors and / or digital signal processors or configurable module components such as FPGA devices.

[0129] The components and features of the embodiments of the application can each be implemented in any suitable way. Indeed, the functionality can be implemented in a single unit, in a plurality of units or as part of other functional units. Although the application has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the application is intended to embrace all such alternatives, modifications and variations as can fall within the scope of the appended claims. In the claims, the term "include" does not exclude other parts but allows to include further components. The term "coupled" does not exclude the presence of intermediate components between the coupled parts.

[0130] Furthermore, although individual features can be included in different claims, these can advantageously be combined, and the inclusion of different claims does not imply that a combination of features is not feasible and / or advantageous. Also, a dependency of a claim on another claim does not mean that a combination of features is not feasible and / or advantageous, even if this dependency is not recited in each claim. Furthermore, inclusion of a particular feature in one category of claims does not mean that the feature cannot be or is not advantageously used in other claim categories. The scope of the application is limited only by the following claims.

[0131] Furthermore, the sequence of features in the claims does not imply any specific order of performing the features, especially in method claims, unless explicitly stated otherwise. In other words, the order of features in the claims does not imply that the features must be performed in that order. Rather, the features can be performed in any suitable order. Furthermore, singular references do not exclude a plurality. Thus references to "a", "an", "first", "second", etc do not exclude a plurality. Also, reference to "one" does not exclude a plurality.

[0132] Although the application has been described in connection with some embodiments, it is not intended to be limited to the particular form set forth herein. Rather, the scope of the present application is limited only by the claims. Furthermore, although features can appear to be described in conjunction with a particular embodiment, one of ordinary skill in the art will understand that a variety of features can be combined in accordance with the application. In the claims, the terms "including" and "comprising" are not restrictive, although the terms "consisting essentially of and "consisting of are restrictive.

Claims

1. A method of enhancing performance of a physical uplink shared channel (PUSCH) repetition type B, for repetition in PUSCH transmission of a UE to a base station in a wireless communication network, the method being performed by the UE, characterized in that, including: receiving a number of repetitions and scheduled resources in the PUSCH transmission; receiving an indication of a procedure to employ when one-symbol repetition occurs; performing a listen-before-talk procedure to acquire the PUSCH; continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition type B; and when the one-symbol repetition occurs, performing an additional listen-before-talk procedure in a time interval of the one-symbol repetition based on the indication.

2. The method of claim 1, wherein, the time interval of the one-symbol repetition and the additional listen-before-talk procedure is equal to a time interval of one OFDM symbol.

3. The method of claim 2, wherein, the time interval of the additional listen-before-talk procedure is configured to fit in the time interval of the one OFDM symbol.

4. The method of claim 1, wherein, the PUSCH transmission is a PUSCH transmission of ultra-reliable, low-latency communication, URLLC, with high priority.

5. The method of claim 1, wherein, receiving the indication includes receiving an explicit signal for the indication.

6. The method of claim 5, wherein, the explicit signal for the indication includes any of a value of an additional bit in a downlink control information, DCI, transmitted by the base station to the UE, an additional parameter in radio resource control, RRC, signaling.

7. The method of claim 1, wherein, receiving the indication includes receiving an implicit signal for the indication.

8. The method of claim 7, wherein, the implicit signal for the indication includes a high value of a priority index for the PUSCH transmission.

9. A UE comprising a processor configured to perform the method of any one of claims 1-8.

10. A non-transitory computer-readable medium storing instructions that, when executed by a computer, perform the method of any one of claims 1-8. 11.A method for enhancing performance of a physical uplink shared channel (PUSCH) repetition type B, for repetitions in PUSCH transmissions of a UE to a base station of a wireless communication network, the method comprising: including: the base station scheduling a number of repetitions and scheduled resources in the PUSCH transmission; the base station establishing an indication of a procedure to employ when one-symbol repetition occurs; the UE receiving the number of repetitions and the scheduled resources in the PUSCH transmission; the UE receiving the indication of the procedure to employ when the one-symbol repetition occurs; the UE performing a listen-before-talk procedure to acquire the PUSCH; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition type B; wherein when the one-symbol repetition occurs, the indication of the procedure to employ when the one-symbol repetition occurs causes the UE to perform an additional listen-before-talk procedure in a time interval of the one-symbol repetition. 12.A method for enhancing performance of a physical uplink shared channel (PUSCH) repetition type B, for repetition in PUSCH transmission of a UE to a base station in a wireless communication network, the method being performed by the UE, characterized in that, including: receiving a number of repetitions and scheduled resources in the PUSCH transmission; receiving an indication to employ a listen-before-talk procedure when the PUSCH transmission is interrupted; performing the listen-before-talk procedure to acquire the PUSCH; and continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition type B; wherein when an interruption in transmission of the repetitions in the PUSCH transmission is encountered, the indication to employ a listen-before-talk procedure when the PUSCH transmission is interrupted causes the UE to continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition type B without performing an additional listen-before-talk procedure.

13. The method of claim 12, wherein, The PUSCH transmission is a PUSCH transmission of high priority ultra-reliable low latency communication, URLLC.

14. The method of claim 12, wherein, The indication to employ a listen-before-talk procedure at interruption of the PUSCH transmission comprises an explicit signal for the indication.

15. The method of claim 14, wherein, The explicit signal for the indication comprises any of a value of an additional bit in a downlink control information, DCI, transmitted by the base station to the UE, an additional parameter in radio resource control, RRC, signaling.

16. The method of claim 12, wherein, The indication to employ a listen-before-talk procedure at interruption of the PUSCH transmission comprises an implicit signal for the indication.

17. The method of claim 16, wherein, The implicit signal for the indication comprises a high value of a priority index for the PUSCH transmission.

18. The method of claim 12, wherein, The interruption of the repeated transmissions in the PUSCH transmission is due to presence of DL symbols during the repeated transmissions, and the indication to employ the listen-before-talk procedure at interruption of the PUSCH transmission due to the presence of the DL symbols comprises an explicit signal comprising any of a value of an additional bit in a DCI transmitted by the base station to the UE, an additional parameter in RRC signaling.

19. The method of claim 12, wherein, The interruption of the repeated transmissions in the PUSCH transmission is due to presence of invalid symbols during the repeated transmissions, and the indication to employ the listen-before-talk procedure at interruption of the PUSCH transmission due to the presence of the invalid symbols comprises an explicit signal comprising any of a value of an additional bit in a DCI transmitted by the base station to the UE, an additional parameter in RRC signaling.

20. The method of claim 12, wherein, The interruption of the repeated transmissions in the PUSCH transmission is due to a slot boundary that results in one-symbol repetition, and the indication to employ the listen-before-talk procedure at interruption of the PUSCH transmission due to the slot boundary that results in one-symbol repetition comprises an explicit signal comprising any of a value of an additional bit in a DCI transmitted by the base station to the UE, an additional parameter in RRC signaling.

21. The method of claim 14, wherein, The explicit signal comprises a value of a first additional bit in a DCI for interruption due to any of presence of DL symbols, presence of invalid symbols, and a value of a second additional bit in a DCI for interruption due to a slot boundary that results in one-symbol repetition.

22. The method of claim 14, wherein, The explicit signal comprises a first additional parameter in RRC signaling for interruption due to any of presence of DL symbols, presence of invalid symbols, and a second additional parameter in RRC signaling for interruption due to a slot boundary that results in one-symbol repetition.

23. A UE comprising a processor configured to perform the method of any one of claims 12 to 22.

24. A non-transitory computer-readable medium storing instructions that, when executed by a computer, perform the method of any one of claims 12 to 22.

25. A method for enhancing the performance of Physical Uplink Shared Channel (PUSCH) repetition type B, used for repetition in PUSCH transmission from UE to base station in a wireless communication network, characterized in that, comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a listen-before-talk procedure to employ at interruption of the PUSCH transmission; the UE receives the indication of the listen-before-talk procedure to employ upon interruption of the PUSCH transmission; the UE employs the listen-before-talk procedure to acquire the PUSCH; and the UE continues transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; wherein the indication of the listen-before-talk procedure to employ upon interruption of the PUSCH transmission causes the UE to continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B without performing an additional listen-before-talk procedure when an interruption in transmission of the repetitions in the PUSCH transmission is encountered. comprising: 26.A method of enhancing performance of PUSCH repetition Type B, for repetition in PUSCH transmission of a UE to a base station of a wireless communication network, the method being performed by the UE, the method comprising: receiving scheduled resources in the PUSCH transmission and a number of repetitions; receiving an indication of a transmission procedure to employ when the one-symbol repetition occurs; employing the listen-before-talk procedure to acquire the PUSCH; and continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; wherein the indication of the transmission procedure to employ when the one-symbol repetition occurs causes the UE to continue transmission of the one-symbol repetition and further repetitions in the PUSCH transmission using the PUSCH repetition Type B. the PUSCH transmission is a PUSCH transmission of ultra-reliable, low-latency communication (URLLC) with high priority.

27. The method of claim 26, wherein, the one-symbol repetition includes a DMRS.

28. The method of claim 26, wherein, the indication of the transmission procedure to employ when the one-symbol repetition occurs includes an explicit signal for the indication.

29. The method of the preceding claim 26, characterized by, the explicit signal for the indication includes any one of a value of an additional bit in downlink control information (DCI) transmitted by the base station to the UE, an additional parameter in radio resource control (RRC) signaling.

30. The method of claim 29, wherein, the indication of the transmission procedure to employ when the one-symbol repetition occurs includes an implicit signal for the indication, the implicit signal including a high value of a priority index for the PUSCH transmission.

31. The method of claim 26, wherein, 32. A UE comprising a processor configured to perform the method of any one of claims 26-31.

33. A non-transitory computer-readable medium storing instructions that, when executed by a computer, perform the method of any one of claims 26-31. comprising: 34.A method of enhancing performance of PUSCH repetition Type B for repetitions in PUSCH transmissions from a UE to a base station of a wireless communication network, the method comprising: the base station schedules resources in the PUSCH transmission and a number of repetitions; the base station establishes an indication of a transmission procedure to employ when the one-symbol repetition occurs; the UE receives the scheduled resources in the PUSCH transmission and the number of repetitions; the UE receives the indication of the transmission procedure to employ when the one-symbol repetition occurs; the UE employs the listen-before-talk procedure to acquire the PUSCH; and the UE continues transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; the indication of the transmission procedure to employ when the one-symbol repetition occurs causes the UE to continue transmission of the one-symbol repetition and further repetitions in the PUSCH transmission using the PUSCH repetition Type B. ​ When the one-symbol repetition occurs, the indication of the transmission procedure employed upon interruption of the PUSCH transmission causes the UE to continue transmission of the one-symbol repetition and further repetitions in the PUSCH transmission using the PUSCH repetition Type B. 35.A method of enhancing performance of PUSCH repetition Type B, for repetition in PUSCH transmission of a UE to a base station of a wireless communication network, the method being performed by the UE, characterized in that, Comprising: receiving scheduled resources, number of repetitions, and DL symbols in the PUSCH transmission; receiving an indication of a transmission procedure employed upon interruption of the PUSCH transmission; performing a listen-before-talk procedure to acquire the PUSCH in unlicensed spectrum; and continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B. When encountering an interruption in transmission of the repetitions in the PUSCH transmission, the indication of the transmission procedure employed upon interruption of the PUSCH transmission causes the UE to switch at least some DL symbols to UL symbols and continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B through UL symbols.

36. The method of claim 35, wherein, When the base station has no DL data to transmit through the DL symbols, the indication of the transmission procedure employed upon interruption of the PUSCH transmission causes the UE to switch all DL symbols to UL symbols.

37. The method of claim 35, wherein, When the base station has DL data to transmit through the DL symbols and the repeated UL data has a higher priority than the DL data, the indication of the transmission procedure employed upon interruption of the PUSCH transmission causes the UE to switch all DL symbols to UL symbols.

38. The method of claim 35, wherein, For dynamic grant, DG, transmission, the indication of the transmission procedure employed upon interruption of the PUSCH transmission includes any one of a dynamic SFI signal sent to the UE, a value of an additional bit of a DCI for UL resource grant, a high value of a priority index for the PUSCH transmission.

39. The method of claim 35, wherein, For configured grant, CG, transmission, the indication of the transmission procedure employed upon interruption of the PUSCH transmission includes any one of a high value of a priority index for the PUSCH transmission, a DCI format 2 0.

40. A UE comprising a processor configured to perform the method of any one of claims 35-39.

41. A non-transitory computer-readable medium storing instructions that, when executed by a computer, perform the method of any one of claims 35-39.

42. A method of enhancing performance of PUSCH repetition Type B for repetitions in PUSCH transmissions of a UE to a base station of a wireless communication network, the method comprising: Comprising: the base station scheduling resources, number of repetitions, and DL symbols in the PUSCH transmission; the base station establishing an indication of a transmission procedure employed upon interruption of the PUSCH transmission; the UE receiving scheduled resources, number of repetitions, and DL symbols in the PUSCH transmission; the UE receiving the indication of the transmission procedure employed upon interruption of the PUSCH transmission; the UE performing a listen-before-talk procedure to acquire the PUSCH in unlicensed spectrum; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B. the UE receiving scheduled resources, number of repetitions, and DL symbols in the PUSCH transmission; the UE receiving the indication of the transmission procedure employed upon interruption of the PUSCH transmission; the UE performing a listen-before-talk procedure to acquire the PUSCH in unlicensed spectrum; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B. When an interruption in transmission of the repetitions in the PUSCH transmission is encountered, the indication of the transmission procedure employed at the interruption in the PUSCH transmission causes the UE to switch at least some DL symbols to UL symbols and continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B through UL symbols.

43. A method of enhancing performance of PUSCH repetition Type B for repetitions in PUSCH transmissions of a UE to a base station of a wireless communication network, the method being performed by the UE, the method comprising: comprising: receiving a number of repetitions and scheduled resources in the PUSCH transmission; receiving an indication of a transmission procedure employed at an interruption in the PUSCH transmission; performing a listen-before-talk procedure to gain access to the PUSCH in unlicensed spectrum; and continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B through the scheduled resources; When an interruption in transmission of the repetitions in the PUSCH transmission is encountered, the indication of the transmission procedure employed at the interruption in the PUSCH transmission causes the UE to continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B through semi-static flexible symbols in the scheduled resources.

44. A UE comprising a processor configured to perform the method of claim 43.

45. A non-transitory computer-readable medium storing instructions that, when executed by a computer, perform the method of claim 43. 46.A method of enhancing performance of PUSCH repetition Type B for repetitions in PUSCH transmissions from a UE to a base station of a wireless communication network, the method comprising: comprising: the base station scheduling resources and a number of repetitions in the PUSCH transmission; the base station establishing an indication of a transmission procedure employed at an interruption in the PUSCH transmission; the UE receiving a number of repetitions and scheduled resources in the PUSCH transmission; the UE receiving the indication of the transmission procedure employed at the interruption in the PUSCH transmission; the UE performing a listen-before-talk procedure to gain access to the PUSCH in unlicensed spectrum; and the UE continuing transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B; When an interruption in transmission of the repetitions in the PUSCH transmission is encountered, the indication of the transmission procedure employed at the interruption in the PUSCH transmission causes the UE to continue transmission of the repetitions in the PUSCH transmission using the PUSCH repetition Type B through semi-static flexible symbols in the scheduled resources. ​

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