EP4691011A1

EP4691011A1 - Method, user equipment and access network node

Info

Publication number: EP4691011A1
Application number: EP24716887.5A
Authority: EP
Inventors: Xuelong Wang; Yuhua Chen; Pravjyot Deogun; Hisashi Futaki
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2023-03-31
Filing date: 2024-03-19
Publication date: 2026-02-11
Also published as: GB202304882D0; JP2026511468A; WO2024203646A1; GB2628669A; CN120917821A

Abstract

Various access network nodes and user equipment are disclosed that can operate both configuration grant and cell DTX/DRX. In some aspects, a user equipment, UE, receives from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node; receives first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; transmits first uplink data to the access network node in a first TO of said plurality of TOs at a timing when said access network node is in said active period; wherein the UE is configured to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO; determines from the configured grant and said first information if the access network node is in said inactive period during said second TO; and in a case where the access network node is in said inactive period during said second TO, delays, or stops, sending of said first retransmission of the first uplink data.

Description

METHOD, USER EQUIPMENT AND ACCESS NETWORK NODE

　　The present disclosure relates to a communication system and to parts thereof.

　　The disclosure has particular but not exclusive relevance to wireless communication systems and devices thereof operating according to the 3rd Generation Partnership Project (3GPP) standards or equivalents or derivatives thereof (including LTE-Advanced, Next Generation or 5G networks, future generations, and beyond). The disclosure has particular, although not necessarily exclusive, relevance to cell discontinuous reception (DRX) and cell discontinuous transmission (DTX) to reduce energy consumption within the network and the ramifications of using such network energy saving (NES) techniques with regard to Configured Grants (CG) that have been allocated to user equipment (UE) and Buffer Status Reporting (BSR).

　　Recent developments of the 3GPP standards are referred to as the Long-Term Evolution (LTE) of Evolved Packet Core (EPC) network and Evolved UMTS Terrestrial Radio Access Network (E-UTRAN), also commonly referred as '4G'. In addition, the term '5G' and 'new radio' (NR) refer to an evolving communication technology that is expected to support a variety of applications and services. Various details of 5G networks are described in, for example, the 'NGMN 5G White Paper' V1.0 by the Next Generation Mobile Networks (NGMN) Alliance, which document is available from https://www.ngmn.org/5g-white-paper.html. 3GPP intends to support 5G by way of the so-called 3GPP Next Generation (NextGen) radio access network (RAN) and the 3GPP NextGen core network.

　　Under the 3GPP standards, a NodeB (or an eNB in LTE, gNB in 5G) is the radio access network (RAN) node (or simply 'access node', 'access network node' or 'base station') via which communication devices (user equipment or 'UE') connect to a core network and communicate with other communication devices or remote servers. For simplicity, the present application will use the term RAN node or base station to refer to any such access nodes.

PTL 1: US2016/0088681A
PTL 2: US2023/0020254A

NPL 1: the 'NGMN 5G White Paper' V1.0 by the Next Generation Mobile Networks (NGMN) Alliance, available from https://www.ngmn.org/5g-white-paper.html

　　There is a need for improved wireless communication networks having improved energy efficiency. A reduction in the amount of energy needed to operate a communication network beneficially reduces the environmental impact of operating the system, and also reduces the operational costs. Moreover, for battery-powered devices (for example, a UE) reduced power consumption extends the battery life of the device.

　　One method of achieving a more efficient communication network is to reduce the energy requirements of the radio access network part of the system. The energy consumption of the radio access network includes a dynamic part that is associated with data transmission and reception, and a static part that is associated with operations of the radio access devices that are performed even when there is no ongoing data transmission or reception. The static part may include, for example, the power required to operate a UE in a mode in which the UE is able to receive and decode a physical downlink control channel (PDCCH) transmitted by a base station. Energy saving modes may be configured for one or more devices in the system (e.g. a UE). For example, a UE may be configured to operate in an energy saving mode (which may also be referred to as a sleep mode) in which the UE performs a reduced number of transmissions, or in which the UE is configured not to attempt to transmit or receive signals during a particular time period. Such operation is commonly referred to as DRX/DTX which stands for Discontinuous Reception (DRX) and Discontinuous Transmission (DTX).

　　Many proposals have been made for UE DTX/DRX operation and attention is turning now to such discontinuous operation of one or more base station cells - which are referred to as "cell DTX/DRX". With cell DTX/DRX, the cell (RAN node) stops transmitting and receiving during certain periods of time and the UEs that are served by the cell should know when the RAN node is in the active state (and is therefore able to communicate with the UE) and when it is in the inactive state (and is therefore not able to communicate with the UE). However, the introduction of such cell DTX/DRX has ramifications for other features of the communication system and in particular Configuration Grants (CG) that have been allocated to UEs.

　　More specifically, when a UE wishes to transmit data in the uplink to the base station, it must be configured with uplink resources on which it can transmit its uplink data. Typically, the UE transmits information to the base station indicating that it has uplink data to be transmitted. The base station then dynamically allocates specific resources for the UE to use to transmit its data. However, this process can be quite inefficient particularly when it is known in advance that the UE is going to want to transmit uplink data regularly (for instance when the UE is in a call). To cater for this, the base station can configure periodic resources that the UE can use for uplink transmissions without the user having to request those resources each time it has data to send. These resources are configured by the base station in a "Configuration Grant" message. Since a cell is only configured for cell DTX/DRX during periods when the cell is not busy, the base station does not know when it might transition into a cell DTX/DRX inactive period at the time that it establishes Configuration Grants for the different UEs it is serving and therefore it is possible that the base station may be in a DTX/DRX inactive period at the time when a particular UE has scheduled resources for an uplink transmission.

　　Further, to improve CG transmission reliability, the base station may allocate additional redundant allocations or Transmission Opportunities (TOs) within a predefined period thereby allowing multiple repeat transmissions of the uplink data in that period. The base station and the UEs need to know what to do in the situation where that period overlaps with a cell DTX/DRX inactive period.

　　There is therefore a need to provide solutions for these scenarios. The disclosure aims to provide apparatus and methods that at least partially addresses one or more of the above needs and/or issues.

　　According to one aspect, there is provided a method performed by a user equipment, UE, the method comprising: receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node; receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; transmitting first uplink data to the access network node in a first TO of said plurality of TOs at a timing when said access network node is in said active period; wherein the UE is configured to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO; determining from the configured grant and said first information if the access network node is in said inactive period during said second TO; and in a case where the access network node is in said inactive period during said second TO, delaying, or stopping, sending of said first retransmission of the first uplink data. Typically, the first information is received from the access network node, although in some aspects, the UE may obtain this information from another network node or from another UE.

In a case where the access network node is in said inactive period during said second TO, the method may include delaying sending of said first retransmission of the first uplink data in a case where the UE has not received an acknowledgement of receipt of the first uplink data.

In a case where the access network node is in said inactive period during said second TO, the method may include stopping sending of said first retransmission of the first uplink data in a case where the UE has received an acknowledgement of receipt of the first uplink data.

The UE may be configured to transmit a second retransmission of the first uplink data to the access network node in a third TO that is after the second TO; and wherein in the case that the second TO partially overlaps with said inactive period and partially overlaps with said active period, the method may send the first retransmission in the second TO and in a case where the access network node is in said inactive period during said third TO, the method may delay, or stop, sending of said second retransmission of the first uplink data.

　　The method may further comprise monitoring a first physical downlink control channel, PDCCH, occasion that follows the inactive period of the access network node to acquire a dynamic grant for an uplink transmission. In the case that a dynamic grant is acquired for the UE, the method may transmit uplink data to the access network node using resources allocated by the dynamic grant. The uplink data transmitted using the dynamic grant may comprise a retransmission of said first uplink data.

The method may further comprise transmitting a retransmission of said first uplink data in a first available TO that overlaps with the active period of the access network node following an inactive period of the access network node.

　　The method may further comprise running a CG Retransmission Timer, CGRT, and in the event that the first uplink data transmission is not acknowledged by the access network node before the start of the inactive period, stopping or extending the CGRT and not autonomously retransmitting the first uplink data in a subsequent TO. If a duration of the CGRT plus a duration of the inactive period of the access network node is larger than a delay budget for the first uplink data, the method may stop further retransmission of the first uplink data and transmitting second uplink data in a TO following the end of the inactive period. The method may also automatically disable CGRT based retransmissions during said inactive period.

　　In some aspects, the method further comprises running a CG Timer, CGT, for limiting a number repetitions that are transmitted of said first data; and stopping or suspending the CGT during said inactive period of the access network node. In this case, the method may further comprise restarting or recovering the CGT at the end of the inactive period of the access network node or it may comprise automatically disabling CRT based retransmissions during said inactive period.

　　The method may further comprise receiving second information from the access network node indicating that the UE should perform a retransmission of the first uplink data in a TO that overlaps with said inactive period, and in response to receiving said second information, transmitting a retransmission of said first uplink data during the inactive period of the access network node. The second information may comprise a UE specific drx-InactivityTimer.

　　The first uplink data may be transmitted on a Physical Uplink Shared Channel, PUSCH, and the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots. In this case, the UE may drop or suspend PUSCH repetition based uplink transmission during the inactive period of the access network node. Alternatively, the UE may reduce a repetition number of the PUSCH for any time slot that fully overlaps with the inactive period of the access network node. Or the UE may reduce a repetition number of the PUSCH for any time slot that fully overlaps and that partially overlaps with the inactive period of the access network node.

　　The method may comprise receiving from the access network node a plurality of Configured Grants, CGs, that each defines a plurality of periodic uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, and wherein the plural CGs configure the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node. The UE may drop or suspend PUSCH based uplink transmission during a period if any time slot within that period fully overlaps with the inactive period of the access network node. If a CG period partially overlaps with the inactive period of the access network node, then the UE may transmit the uplink data in a first available CG TO time slot of the CG period that overlaps with the inactive period of the access network node. The UE may drop or suspend PUSCH based uplink transmission during a period if any time slot within that period fully overlaps and if any time slot within that period partially overlaps with the inactive period of the access network node.

　　In some aspects, the UE reduces a repetition number of the PUSCH for any time slot that fully overlaps and that partially overlaps with the inactive period of the access network node. In this case, the UE may transmit the uplink data in a first available CG TO time slot of a CG period that fully overlaps with a next active period of the access network node.

　　The method may comprise receiving a Buffer Status Report, BSR, for transmission to the access network node during the inactive period of the access network node; and transmitting a Scheduling Request, SR, to the access network node to obtain a Dynamic Grant, DG, of uplink resources on which to transmit the BSR. The method may further comprise receiving the DG from the access network node and transmitting the BSR on the resources granted by the DG in a case where those resources are before a next available CG TO. Alternatively, the UE may transmit the BSR on the resources granted by the next available CG TO in a case where the resources granted by the DG are after the resources granted by the next available CG TO.

　　In some aspects, the method comprises determining when the access network node transitions from the inactive period to the active period and in response to such transition, transmitting the SR to the access network node. In other aspects, the method further comprises determining when the access network node transitions from the inactive period to the active period and a timing of a next available CG TO during the next access node active period and deciding not to transmit the SR to the access network node if the next available CG TO during the next access node active period falls within a threshold time period of a start of the access network node active period.

　　According to another aspect, there is provided a method performed by a user equipment, UE, the method comprising: receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, and the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node; receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; determining from the configured grant and said first information if the access network node is in said inactive period during any time slot configured for PUSCH transmission; in the case where the a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, the UE uses at least one transmission parameter associated with the (N+1)th repetition to transmit the first repetition of the PUSCH in the (N+1)th time slot and/or the UE uses at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to transmit the first repetition of the PUSCH in the (N+1)th time slot.

　　According to another aspect, there is provided a method performed by a user equipment, UE, the method comprising: configuring a first timer indicating how long after transmitting uplink data to an access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data; configuring a second timer that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data; receiving from an access network node a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node; transmitting first uplink data to the access network node using the one or more resources; receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; determining if the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node; and in a case where the first timer has started, extending the first timer to run until the end of the inactive period of the access network node and starting the second timer once the access network node is in the active period following the end of the inactive period.

　　In a case where the first timer has not started, the method may skip the running of the first timer and start the second timer once the access network node is in the active period following the end of the inactive period.

　　In some aspects, the UE sleeps in a period between transmitting the first uplink data and the running of the second timer.

　　According to another aspect, there is provided a method performed by an access network node, the method comprising: transmitting to a User Equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node; transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; receiving first data corresponding to first uplink data transmitted from the UE in a first TO of said plurality of TOs at a timing when said access network node is in said active period; wherein the CG configures resources for the UE to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO; wherein in a case where the second TO is in said inactive period of the access network node and the access network node has not acknowledged receipt of the first uplink data: i) maintaining the first data in an uplink buffer associated with the UE, ii) receiving, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recovering the first uplink data using the first data and the second data.

　　In a case where the second TO is in said inactive period of the access network node and the access network node has acknowledged receipt of the first uplink data, the method may provide the first uplink data to higher layers and flush the uplink buffer associated with the UE. In the case that the second TO partially overlaps with said inactive period and partially overlaps with said active period, the method may receive the first retransmission in the second TO.

　　The method may further comprise providing a dynamic grant to the UE for an uplink transmission and receiving uplink data from the UE using resources allocated by the dynamic grant. The uplink data transmitted using the dynamic grant may comprise a retransmission of said first uplink data.

　　The method may further comprise receiving a retransmission of said first uplink data in a first available TO that overlaps with an active period of the access network node following an inactive period of the access network node.

　　The method may further comprise transmitting second information to the UE indicating that the UE should perform a retransmission of the first uplink data in a TO that overlaps with said inactive period, and receiving a retransmission of said first uplink data during the inactive period of the access network node. The second information may comprise a UE specific drx-InactivityTimer.

　　The first uplink data may be received on a Physical Uplink Shared Channel, PUSCH, and the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots. In some aspects, the method comprises transmitting to the UE a plurality of Configured Grants, CGs, that each defines a plurality of periodic uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, and wherein the plural CGs configure the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node. In this case, if a CG period partially overlaps with the inactive period of the access network node, the method may receive uplink data in a first available CG TO time slot of the CG period that overlaps with the inactive period of the access network node.

　　The method may comprise receiving a Scheduling Request, SR, from the UE to obtain a Dynamic Grant, DG, of uplink resources on which to transmit a Buffer Status Report, BSR; transmitting the DG to the UE and receiving the BSR on the resources granted by the DG in a case where those resources are before a next available CG TO. The method may receive the BSR on the resources granted by the next available CG TO in a case where the resources granted by the DG are after the resources granted by the next available CG TO.

　　According to another aspect, there is provided a method performed by an access network node, the method comprising: transmitting to a user equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, to the access network node and wherein the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node; transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; in the case where a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, receiving a first repetition of the PUSCH from the UE in the (N+1)th time slot, wherein the access network node uses at least one transmission parameter associated with the (N+1)th repetition to receive the first repetition of the PUSCH in the (N+1)th time slot and/or the access network node uses at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to receive the first repetition of the PUSCH in the (N+1)th time slot.

　　According to another aspect, there is provided a method performed by an access network node, the method comprising: transmitting first timer data to a user equipment, UE, that configures a first timer in the UE indicating how long after transmitting uplink data to the access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data; transmitting second timer data to the UE that configures a second timer in the UE that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data; transmitting to the UE a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node; receiving first data corresponding to first uplink data transmitted from the UE using the one or more resources; transmitting third data indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; and wherein in a case where the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node: i) maintaining the first data in an uplink buffer associated with the UE, ii) receiving, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recovering the first uplink data using the first data and the second data.

　　The disclosure also provides corresponding apparatus according to any of the above aspects.

　　According to another aspect, there is provided a user equipment, UE, comprising: means for receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node; means for receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; means for transmitting first uplink data to the access network node in a first TO of said plurality of TOs at a timing when said access network node is in said active period; wherein the UE is configured to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO; means for determining from the configured grant and said first information if the access network node is in said inactive period during said second TO; and in a case where the access network node is in said inactive period during said second TO, the UE is configured to delay, or stop, sending said first retransmission of the first uplink data.

　　According to another aspect, there is provided a user equipment, UE, comprising: means for receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, and the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node; means for receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; means for determining from the configured grant and said first information if the access network node is in said inactive period during any time slot configured for PUSCH transmission; in the case where the a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, the UE is configured to use at least one transmission parameter associated with the (N+1)th repetition to transmit the first repetition of the PUSCH in the (N+1)th time slot and/or the UE is configured to use at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to transmit the first repetition of the PUSCH in the (N+1)th time slot.

　　According to another aspect, there is provided a user equipment, UE, comprising: means for configuring a first timer indicating how long after transmitting uplink data to an access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data; means for configuring a second timer that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data; means for receiving from an access network node a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node; means for transmitting first uplink data to the access network node using the one or more resources; means for receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; means for determining if the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node; and in a case where the first timer has started, the UE is configured to extend the first timer to run until the end of the inactive period of the access network node and to start the second timer once the access network node is in the active period following the end of the inactive period.

　　According to another aspect, there is provided an access network node comprising: means for transmitting to a User Equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node; means for transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; means for receiving first data corresponding to first uplink data transmitted from the UE in a first TO of said plurality of TOs at a timing when said access network node is in said active period; wherein the CG configures resources for the UE to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO; wherein in a case where the second TO is in said inactive period of the access network node and the access network node has not acknowledged receipt of the first uplink data, the access network node is configured to: i) maintain the first data in an uplink buffer associated with the UE, ii) receive, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recover the first uplink data using the first data and the second data.

　　According to another aspect, there is provided an access network node comprising: means for transmitting to a user equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, to the access network node and wherein the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node; means for transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; in the case where a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, the access network node is configured to receive a first repetition of the PUSCH from the UE in the (N+1)th time slot, and is configured to use at least one transmission parameter associated with the (N+1)th repetition to receive the first repetition of the PUSCH in the (N+1)th time slot and/or the access network node is configured to use at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to receive the first repetition of the PUSCH in the (N+1)th time slot.

　　According to another aspect, there is provided an access network node, the method comprising: means for transmitting first timer data to a user equipment, UE, that configures a first timer in the UE indicating how long after transmitting uplink data to the access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data; means for transmitting second timer data to the UE that configures a second timer in the UE that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data; means for transmitting to the UE a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node; means for receiving first data corresponding to first uplink data transmitted from the UE using the one or more resources; means for transmitting third data indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; and wherein in a case where the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node, the access network node is configured to: i) maintain the first data in an uplink buffer associated with the UE, ii) receive, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recover the first uplink data using the first data and the second data.

　　The various functional means defined above that are part of the UE may be provided by a memory and one or more processors that execute instructions stored in the memory. Similarly, the various functional means defined above that are part of the access network node may be provided by a memory and one or more processors that execute instructions stored in the memory.

　　The disclosure may also provide a computer program product comprising computer implementable instructions for causing a programmable computer to carry out the method of any of the aspects described above. The computer implementable instructions may be provided as a signal or on a tangible computer readable medium.

　　Example embodiments of the disclosure will now be described, by way of example, with reference to the accompanying drawings in which:

Fig. 1 schematically illustrates a mobile ('cellular' or 'wireless') telecommunication system; Fig. 2 illustrates a typical frame structure that may be used in the telecommunication system of Fig. 1; Fig.3 illustrates a typical resource grid that may be used in the telecommunication system of Fig.1; Fig. 4 illustrates an example of a DRX cycle or pattern; Fig. 5 illustrates an example of a conventional Configuration Grant that includes multiple retransmission opportunities; Fig. 6 illustrates three other examples of conventional Configuration Grants that include multiple retransmission opportunities; Fig. 7 illustrates a situation in which transmission opportunities defined by a Configuration Grant overlap with a cell DRX inactive period; Fig. 8 illustrates the situation shown in Fig. 7 in which transmission opportunities defined by a Configuration Grant overlap with a cell DRX inactive period and showing timings of HARQ retransmissions in accordance with one proposal; Fig. 9 illustrates the situation shown in Fig. 7 in which transmission opportunities defined by a Configuration Grant overlap with a cell DRX inactive period and showing timings of HARQ retransmissions in accordance with another proposal; Fig. 10 illustrates a situation in which repetitions aggregated over consecutive slots overlap with a cell DRX inactive period; Fig. 11 illustrates another situation in which repetitions aggregated over consecutive slots overlap with a cell DRX inactive period; Fig. 12 illustrates a situation in which multiple Configuration Grants have been granted for different data communications and these overlap with the cell DRX inactive time; Fig. 13 illustrates an example of a Configuration Grant that includes multiple retransmission opportunities that overlap with a cell inactive period that is used for Buffer Status Reporting (BSR); Fig. 14 illustrates a further example of a Configuration Grant that includes multiple retransmission opportunities that overlap with a cell inactive period that is used for Buffer Status Reporting (BSR); Fig. 15 illustrates an example of an overlap between timers run in the UE to control a sleep period of the UE and the cell DRX inactive period; Fig. 16 illustrates a proposed increase in duration for a timer run by the UE until an end of the cell DRX inactive period; Fig. 17 is a schematic block diagram illustrating the main components of a UE for the telecommunication system of Fig. 1; and Fig. 18 is a schematic block diagram illustrating the main components of a base station for the telecommunication system of Fig. 1.

Overview
　　An exemplary telecommunication system will now be described in general terms, by way of example only, with reference to Figs. 1, 2 and 3.

　　Fig. 1 schematically illustrates a mobile ('cellular' or 'wireless') communication system 1 to which example embodiments of the present disclosure are applicable.

　　In the communication system 1, user equipment (UEs) 3-1, 3-2, 3-3 (e.g. mobile telephones and/or other mobile or stationary devices) can communicate with each other via a radio access network (RAN) node 5 that operates according to one or more compatible radio access technologies (RATs). In the illustrated example, the RAN node 5 (base station 5) comprises a NR/5G base station or 'gNB' 5 operating one or more associated cells 9. Communication via the base station 5 is typically routed through a core network 7 (e.g. a 5G core network or evolved packet core network (EPC)).

　　As those skilled in the art will appreciate, whilst three UEs 3 and one base station 5 are shown in Fig. 1 for illustration purposes, the system, when implemented, will typically include other base stations 5 and UEs 3.

　　Each base station 5 controls one or more associated cells 9 either directly, or indirectly via one or more other nodes (such as home base stations, relays, remote radio heads, distributed units, and/or the like). It will be appreciated that the base stations 5 may be configured to support 4G, 5G, 6G, and/or any other 3GPP or non-3GPP communication protocols.

　　The UEs 3 and their serving base station 5 are connected via an appropriate air interface (for example the so-called 'Uu' interface and/or the like). Neighbouring base stations 5 may be connected to each other via an appropriate base station to base station interface (such as the so-called 'X2' interface, 'Xn' interface and/or the like).

　　The core network 7 includes a number of logical nodes (or 'functions') for supporting communication in the telecommunication system 1. In this example, the core network 7 comprises control plane functions (CPFs) 10 and one or more user plane functions (UPFs) 11. The CPFs 10 include one or more Access and Mobility Management Functions (AMFs) 10-1, one or more Session Management Functions (SMFs) 10-2 and a number of other functions 10-n.

　　The base station 5 is connected to the core network nodes via appropriate interfaces (or 'reference points') such as an N2 reference point between the base station 5 and the AMF 10-1 for the communication of control signalling, and an N3 reference point between the base station 5 and each UPF 11 for the communication of user data. The UEs 3 are each connected to the AMF 10-1 via a logical non-access stratum (NAS) connection over an N1 reference point (analogous to the S1 reference point in LTE). It will be appreciated that N1 communications are routed transparently via the base station 5.

　　One or more UPFs 11 are connected to an external data network 20 (e.g. an IP network such as the internet) via reference point N6 for communication of the user data.

　　The AMF 10-1 performs mobility management related functions, maintains the NAS signalling connection with each UE 3 and manages UE registration. The AMF 10-1 is also responsible for managing paging. The SMF 10-2 provides session management functionality (that formed part of MME functionality in LTE) and additionally combines some control plane functions (provided by the serving gateway and packet data network gateway in LTE). The SMF 10-2 also allocates IP addresses to each UE 3.

　　The base station 5 of the communication system 1 is configured to operate at least one cell 9 on an associated TDD carrier that operates in unpaired spectrum. It will be appreciated that the base station 5 may also operate at least one cell 9 on an associated FDD carrier that operates in paired spectrum.

　　The base station 5 is also configured for transmission of, and the UEs 3 are configured for the reception of, control information and user data via a number of downlink (DL) physical channels. The DL physical channels correspond to resource elements (REs) carrying information originated from a higher layer. The physical channels may include, for example, a physical downlink shared channel (PDSCH), a physical broadcast channel (PBCH), and a physical downlink control channel (PDCCH). The PDSCH carries data sharing the PDSCH's capacity on a time and frequency basis. The PDSCH can carry a variety of items of data including, for example, user data, UE-specific higher layer control messages mapped down from higher channels, system information blocks (SIBs), and paging. The PDCCH carries downlink control information (DCI) for supporting a number of functions including, for example, scheduling the downlink transmissions on the PDSCH and also the uplink data transmissions on a physical uplink shared channel (PUSCH). The PBCH provides UEs 3 with the Master Information Block, MIB. It also, in conjunction with the PDCCH, supports the synchronisation of time and frequency, which aids cell acquisition, selection and re-selection.

　　The base station 5 also transmits DL physical signals that do not carry any data, such as, for example, reference signals (RSs) and synchronization signals (SSs). A reference signal (sometimes known as a pilot signal) is a signal with a predefined special waveform known to both the UE 3 and the base station 5. The reference signals may include, for example, cell specific reference signals, UE-specific reference signal (UE-RS), downlink demodulation signals (DMRS), and channel state information reference signal (CSI-RS).

　　Similarly, the UEs 3 are configured for transmission of, and the base station 5 is configured for the reception of, control information and user data via a number of uplink (UL) physical channels corresponding to REs carrying information originated from a higher layer, and UL physical signals which are used in the physical layer and correspond to REs which do not carry information originated from a higher layer. The physical channels may include, for example, the PUSCH, a physical uplink control channel (PUCCH), and/or a physical random-access channel (PRACH). The UL physical signals may include, for example, demodulation reference signals (DMRS) for an UL control/data signal, and/or sounding reference signals (SRS) used for UL channel measurement.

Frame Structure
　　Referring to Fig. 2, which illustrates the typical frame structure that may be used in the communication system 1, the base station 5 and UEs 3 of the communication system 1 communicate with one another using resources that are organised, in the time domain, into frames in this case of length 10ms. Each frame comprises ten equally sized subframes of 1 ms length. Each subframe is divided into one or more slots comprising 14 (or in some cases 12) orthogonal frequency-division multiplexing (OFDM) symbols of equal length.

　　As seen in Fig. 2, the communication system 1 supports multiple different numerologies (subcarrier spacing (SCS), slot lengths and hence OFDM symbol lengths). Specifically, each numerology is identified by a parameter, μ, where μ=0 represents 15 kHz (corresponding to the LTE SCS). Currently, the SCS for other values of μ can, in effect, be derived from μ=0 by scaling up in powers of 2 (i.e. SCS = 15 x 2μ kHz). The relationship between the parameter, μ, and SCS (Δf) is as shown in Table 1:

　　Fig. 3 illustrates the resource grid of a subframe shown in Fig. 2. As shown, the subcarrier spacing, the number of OFDM symbols within a subframe varies depending on the numerology. A single block shown in Fig. 3 corresponds to a single Resource Element and this is the smallest unit of the resource grid and is made up of one subcarrier in the frequency domain and one OFDM symbol in the time domain. A Resource Block 25 is defined only for the frequency domain and is defined as twelve consecutive subcarriers in the frequency domain in one OFDM symbol.

DTX/DRX
　　A UE 3 may be configured to operate using a discontinuous reception (DRX) method. In a DRX method, the UE 3 is configured with a DRX configuration that includes a DRX pattern and a periodicity (DRX cycle) and optionally a number of DRX cycles. The DRX pattern defines "ON durations" in which the UE 3 is configured for receiving transmissions and "OFF durations" in which the UE 3 is not configured for receiving transmissions (e.g. transmissions from a base station 5). During the OFF durations the physical layer processing may be turned off within the UE 3. Advantageously, the energy consumption of the UE 3 is reduced in the periods in which the UE 3 is not configured for receiving transmissions.

　　The UE 3 is typically provided with its DRX configuration by or via the base station 5. A DRX configuration provided to the UE 3 (for example, using a DRX configuration information element (IE) included in a transmission from the base station 5 to the UE 3) may include, as mentioned above, an indication of a time period (OFF duration) for which the UE 3 is to be configured in a state in which the UE 3 does not receive and decode downlink transmissions, and an indication of a time period (ON duration) for which the UE 3 is to be configured for receiving downlink transmissions (e.g. a multicast or unicast transmission from the base station 5). The DRX configuration may also include a time offset, which may be useful for controlling the relative timing of the DRX configurations of different UEs 3 (e.g. to synchronise or offset the DRX patterns). The DRX configuration may also include an indication of a time period in which the UE is to remain configured for receiving transmissions following the reception of a PDCCH.

　　The ON duration may also be referred to as the 'DRX active time', and the OFF duration may also be referred to as a 'sleep period', or a 'DRX inactive time'. An example of a DRX pattern having an ON duration of t1, and an OFF duration of t2, and which is repeated in accordance with a DRX cycle is illustrated in Fig. 4.

　　DRX may be configured per UE 3 by the network (e.g. via any suitable signalling from the base station 5). For example, the timing and/or duration of the ON durations in the DRX cycle may be different for different UEs 3. During the OFF durations, the UE 3 may be configured to not monitor a PDCCH, but may initiate an uplink transmission based on configured resources (for example, using a PUCCH, a random access channel (RACH), scheduling request (SR) or a configured grant PUSCH (CG-PUSCH)). During an OFF duration, the system may be configured for no transmission/reception between the UE 3 and the base station 5 in a corresponding cell. The base station 5 may nevertheless be configured for reduced or limited transmission/reception in the cell during the OFF duration of the DRX cycle. For example, the base station 5 may be configured to transmit only a subset of periodic signals or channels, such as common channels/signals or UE-specific channels/signals that would normally be transmitted in the cell.

　　DRX may be used when the UE 3 is in an RRC idle mode or when the UE 3 is in an RRC connected mode. For example, DRX may be used when the UE 3 is in an RRC idle mode to control the monitoring of paging messages transmitted by the base station 5. This advantageously prevents the UE 3 from monitoring all of the PDCCH transmission opportunities, thereby reducing the energy usage of the UE 3. Similarly, DRX may be used when the UE 3 is in the RRC connected state (referred to as C-DRX) to reduce the energy usage of the UE 3, for example by configuring periods in which the UE 3 is not required to monitor a PDCCH.

　　Within a C-DRX cycle, when the UE 3 is in an RRC connected state, the UE 3 periodically monitors the PDCCH during the ON durations, and does not monitor PDCCH outside of the ON durations (i.e. in the DRX inactive periods), thereby beneficially reducing the power consumption of the UE 3. Currently, during a C-DRX inactive time, the UE 3 is allowed to initiate an uplink transmission based on configured resources (for example, using a PUCCH, a random access channel (RACH), scheduling request (SR) or on a configured grant PUSCH (CG-PUSCH)).

　　A DRX configuration may also include a long DRX cycle in which the time between the ON durations is relatively large (t2 shown in Fig. 4 is relatively large), and a short DRX cycle in which the time between the ON durations is relatively small (t2 shown in Fig. 4 is relatively small). Whilst the long DRX cycle improves the energy efficiency of the system (because the overall percentage of time in which the UE 3 is in the ON state is smaller), latency of communications may be increased because the base station 5 cannot communicate with the UE 3 via downlink transmissions when the UE 3 is in the sleep state (the DRX inactive state). When the UE 3 is configured to use DRX after a period of inactivity following a data transfer, the UE 3 may be configured to initially use the short DRX cycle configuration, and after a further period of time (which may be defined by a Short DRX Cycle timer) the UE 3 may then operate using the long DRX cycle configuration. The short and long DRX configurations may be indicated to the UE 3, for example, using any suitable signalling from the base station 5 (or alternatively could be preconfigured in the UE 3).

　　Whilst DRX has been described above with reference to discontinuous reception performed by the UE 3, a similar DTX pattern can be defined to control the discontinuous transmission of data by the UE 3. When defined, the UE DTX pattern typically overlaps with the UE DRX pattern - so that when the UE 3 is not receiving data it is also normally not transmitting data.

　　As mentioned above, a base station 5 may also operate one or more of its cells in a DTX/DRX mode in substantially the same way as UE DTX/DRX - stopping the base station's transmissions and receptions during periods of time (OFF duration) when the base station 5 is inactive or asleep and resuming transmissions and receptions with the UEs 3 during periods of time (ON duration) when the base station 5 is active. The cell DTX/DRX configuration can be defined by a number of parameters such as the periodicity (DRX cycle), the start slot/offset, the ON duration (t1), the OFF duration (t2) and the number of cycles etc. as shown in Fig 4.

Configuration Grant
　　As discussed in above, normally when a UE 3 wishes to transmit data in the uplink to the base station 5, it must be configured with uplink resources (resource blocks 25) on which it can transmit its uplink data. Typically, the UE 3 informs the base station 5 that it has uplink data to be transmitted and in response the base station 5 allocates specific time-frequency resource blocks 25 for the UE 3 to use to transmit its data. The control data allocating these resources is transmitted to the UE 3 in the PDCCH. However, this process is inefficient particularly when it is known in advance that the UE 3 will need to transmit regular uplink data (for instance when the UE is in a call) to the base station 5. To cater for this, the base station 5 can configure periodic resource blocks 25 that the UE 3 can use for uplink transmissions without the UE 3 having to request those resources each time it has data to send. These periodic resources are configured by the base station 5 in a "Configuration Grant" (CG). These resources can be configured with two types of procedural signalling, which are Type 1 CG and Type 2 CG.

　　For Type 1 CG, the resource allocation is fully configured using Radio Resource Control (RRC) signalling and do not require any layer 1 signalling on the PDCCH. The RRC signalling defines parameters such as timeDomainOffset, timeDomainAllocation and frequencyDomainAllocation parameters in a ConfiguredGrantConfig information element which provides the information required for the UE 3 to determine the time and frequency resource blocks 25 that have been allocated.

　　For Type 2 CG, the resource allocation uses a combination of RRC signalling and layer 1 signalling on the PDCCH. The RRC signalling provides a subset of the resource allocation information and the remaining information is provided by the PDCCH which also acts as an activation trigger. A subsequent PDCCH transmission can be used as a deactivation trigger. Type 2 CG is very useful for Ultra-Reliable Low Latency Communications (URLLC) services.

　　To improve CG transmission reliability, the allocation can be supported with K consecutive redundant allocations or Transmission Occasions (TOs) within a pre-defined period which allow multiple Transport Blocks (TBs) to be transmitted repeatedly in that period. Repetitions are autonomous and do not require the UE 3 to wait for a request from the base station 5.

　　The length of the period can be established as per the latency budget of the transmission, where the TOs are assigned with a definitive Redundancy Version (RV) pattern. There are four types of RVs defined in NR, RV0, RV1, RV2, and RV3. Data encoded by RV0 and RV3 are self-decodable. As those skilled in the art will be aware, the RV indicates a puncturing pattern that is applied to the data after channel encoding. The details of this processing are not important to the disclosure and will not be described further here.

　　In Release 15, transmission is allowed to begin only at the first TO. However, Release 16 supports flexible beginning of transmission, which provides flexibility in the trade-off between reliability and latency. The transmission reliability is guaranteed as the transmission is always with K repetitions.

　　Fig. 5 illustrates multiple transmission occasions, TOs, 27-1 to 27-4. The UE runs an internal CG Retransmission Timer (CGRT) that defines the spacing between one TO and the next TO. In this example configuration, the uplink data is an HARQ transmission that is transmitted with two repeats in TO 27-2 and 27-3. A second counter Configured Grant Timer defines the timing when the HARQ buffer is flushed and new HARQ data is to be transmitted in this case in the TO 27-4. The Configured Grant Timer defines the period that a UE 3 waits for a retransmission request from the base station 5 after transmitting an uplink packet. The UE 3 assumes a positive acknowledgment if the timer expires and a retransmission request has not been received. This allows the UE 3 to subsequently transmit a new packet using the same HARQ process. The UE 3 may of course have multiple data streams of communication with the base station and a separate HARQ process and CG may be provided for dealing with each HARQ process. In Fig. 5, the CG configuration is for the HARQ process having HARQ ID x.

　　Fig. 6 illustrates other examples of CGs with different repetitions that may be configured. Specifically, in the upper timing diagram in Fig. 6, the period of the Configured Grant Timer is set at 4 slots and in this case the two repetitions are configured to be transmitted in the first two slots of that period. This provides slot aggregation (repetition over consecutive slots). The middle timing diagram illustrates a situation where there are 2 repetitions of mini-slots (illustrated here as 2 OFDM symbols that are spaced apart by 12 OFDM symbols) which again are repeated every 4 slots. In the lower plot, two repetitions of mini-slots (again here corresponding to 2 OFDM symbols) are provided. The two repetitions are consecutive and repeat every 4 slots. In this case, the starting position for the period is not the start of a slot, but the first TO within the slot.

Overlap between CG and Cell DRX
　　As discussed above, issues can occur when TOs overlap with periods when the base station 5 is in a cell DRX/DTX inactive state. Such a scenario is illustrated in Fig. 7, where the second and third TOs (TO-2 and TO-3) overlap with the base station's cell DRX inactive period 29, whereas the first and fourth TOs (TO-1 and TO-4) overlap with the base station's cell DRX active periods 31-1 and 31-2 respectively.

　　In this case the inventors have made the following proposals:

Proposal 1
　　If the initial uplink transmission at CG TO-1 is acknowledged by the base station 5, then the UE 3 automatically (without instruction) skips retransmissions on CG TO-2 and CG TO-3 before any new transmission. Alternatively, the network (for example the base station 5) indicates to the UE to perform such skipping via a piggybacked indication in the acknowledgement (of the transmission in TO-1) to the UE 3.

　　Such initial transmission means the transmission right before the Cell DRX inactive period 29 (in other words, the last CG TO before the following Cell DRX inactive period 29), and in Fig. 7 it is TO-1.

　　The UE 3 monitors the first PDCCH occasion that follows the cell DRX inactive period 29 to determine if the base station 5 has provided any dynamic grant for uplink transmissions to the UE 3.

　　In the case that the CG TO is partially overlapped with the cell DRX inactive period 29 (i.e., part of the CG TO also falls in the cell DRX active period 31), then the inventors propose that the initial transmission and/or retransmission is allowed by the UE 3.

　　Referring now to Fig. 8, if the initial uplink transmission at CG TO-1 (illustrated here as the initial HARQ transmission 35-1) is not acknowledged by the network (e.g. by the base station 5), then the network (e.g. the base station 5) may schedule a dynamic grant to the UE 3 for an HARQ retransmission 35-2, that skips the DRX inactive period 29. This means that the UE 3 needs to monitor the PDCCH to retrieve the dynamic grant for the HARQ retransmission when the base station enters its active period 31-2. As shown in Fig. 8, this dynamic grant may be before CG TO-4 to enable a quick retransmission.

Proposal 2
　　As an alternative to the above in the case where the initial uplink transmission at CG TO-1 (illustrated here as the initial HARQ transmission 35-1) is not acknowledged by the network (e.g. by the base station 5), then the UE 3 may be configured to retransmit the same uplink data (Transport Block, TB) as it transmitted in TO-1 to the base station 5 with the first follow up TO that skips the whole cell DRX inactive period 29 - in Fig. 8 that is TO-4. For such retransmission, the UE 3 uses RV0 or RV3 which ensures that the data is self-decodable by the base station 5 (without requiring another transmission using a different RV). The network (e.g. the base station 5) is configured to decode the retransmitted uplink data (TB) with its previous reception for the same TB based on what was received by the base station 5 when that TB was transmitted by the UE 3 in TO-1 (assuming that successful decoding for that TB was not achieved). The network HARQ buffer (e.g. the HARQ buffer associated with the IE in the base station 5) is not flushed during the cell DRX inactive period 29 to allow the base station 5 to maintain the previously received data for the uplink data. Once the base station 5 has successfully recovered the uplink data it is then passed on to higher layers for further processing before the base station 5 flushes the HARQ buffer associated with that UE 3 so that it is ready for reception of the next uplink data from the UE 3.

Proposal 3
　　In the case where the initial transmission of an uplink TB is performed at CG TO-1 and if the CG Retransmission Timer (CGRT) and the Configured Grant Timer (CGT) are configured, then the UE 3 applies the following for HARQ retransmission if the UE does not receive a CG-DFI (Configured Grant Downlink Feedback Information) from the network acknowledging the receipt of the initial transmission before the start of the cell DRX inactive period 29:
-　　The CG Retransmission Timer (CGRT) is stopped and autonomous CG retransmission is not triggered. UE autonomous CG retransmission is therefore delayed.
-　　The Configured Grant Timer (CGT) is stopped or suspended during the cell DRX inactive period 29, and new data is not transmitted on the first available CG TO following the end of the cell DRX inactive period 29 (i.e., TO-4 shown in Fig. 9 is not used for new data transmission).
-　　The UE automatically performs a retransmission of the initial transmission (performed in TO-1) for HARQ at the first CG TO following the end of the cell DRX inactive period 29 (i.e., TO-4 in Fig. 9).
-　　The Configured Grant Timer (CGT) is restarted or recovered at the end of the cell DRX inactive period 29, or after the first autonomous retransmission by the UE 3.

　　With regard to the Configured Grant Retransmission Timer (CGRT), this would be extended to be the length of the original CGRT plus the length of the cell DRX inactive period 29. However, this extension may make the UE 3 retransmission unnecessary, because that extended retransmission timer may go beyond the Delay Budget for the data transmission (which in turn depends on the allowed latency for the corresponding data stream). Therefore, if the CGRT + the cell DRX inactive period 29 is larger than the Delay Budget for the data transmission (stored in the UE 3), then the UE does not seek to retransmit the HARQ transmission and instead the UE 3 stops the CGRT timer which will be started again when the next uplink transmission (of new data) is made.

Proposal 4
　　As a simpler alternative, in the case where the initial transmission of an uplink TB is performed at CG TO-1 and if the CG Retransmission Timer (CGRT) and the Configured Grant Timer (CGT) are configured, then the UE 3 automatically disables the CGRT/CGT timer based retransmission operation during the cell DTX/DRX operation and therefore the UE disables all new CG transmissions and abandons all retransmissions during the cell DRX inactive period 29.

Proposal 5
　　During the operation of cell DRX and DTX for Rel-18 Network Energy Saving (NES) capable UEs, the disabling of the CG TO (i.e., TO-2 and TO-3 shown in Fig. 9) can be subject to control from the network (e.g. from the base station 5).

　　For example, the base station 5 may detect the UE's need for a retransmission for some particular data, and in this case, the base station 5 may instruct the UE 3 to start a UE specific drx-InactivityTimer that causes the UE 3 to perform some data retransmissions. The base station 5 may instruct the UE 3 using signalling sent to the UE 3 via an L1/L2/L3 message (typically via Downlink Control Information (DCI) transmitted at L1).

　　When the UE 3 receives the drx-InactivityTimer, the UE 3 is configured to take one or more subsequent CG TOs (i.e., TO-2, or both TO-2 and TO-3 as shown in Fig. 9) to perform one or more uplink data retransmissions even though these CG TOs may be overlapped with the cell DRX inactive period. In this case, the disabling of the CG TOs is delayed. For example, if TO-2 shown in Fig. 9 is used for a retransmission, then the first disabled CG TO is TO-3.

Proposal 6
　　In low latency communications, the Physical Uplink Shared Channel (PUSCH) does not cross slot boundaries for both a Dynamic Grant (DG) and a Configured Grant (CG). To avoid transmitting a long PUSCH, the UE 3 transmits small PUSCHs in several repetitions. As shown in Fig. 6, these repetitions can be in adjacent slots and may only use part of each slot or they may be in adjacent mini-slots in the same overall slot (as shown in the lower timing diagram in Fig. 6). In Fig. 10, slot aggregation is depicted, where the repetitions over consecutive slots are supported for Configured Grant (CG) based UL transmission for the UE 3. In Fig. 10, it is assumed that one slot is a transmission occasion of the Configured Grant (CG) and then there are three slots within one transmission period (i.e., 4 slots) for this CG. When cell DTX/DRX is introduced for network energy saving purposes, the situation where a follow-up slot for PUSCH repetition overlaps with the cell DRX inactive period 29 needs to be considered. In this context the follow-up slot means that there is at least one earlier slot falling within the active period 31 of the cell DRX. The inventors propose the following alternatives to deal with this scenario:
Alt-0 - the PUSCH Repetition operation ignores the inactive period of the cell DRX period 29 (which is what legacy UEs will do).
Alt-1 - the PUSCH Repetition based UL transmission is dropped/suspended during the cell DRX inactive period 29 and restored when the cell resumes its cell DRX active period 31.
Alt-2 - the PUSCH Repetition number is reduced so that it only occupies one or more previous slots and the slot that leads the overlap with the cell DRX inactive period 29. In the example shown in Fig. 10, the PUSCH is initially transmitted in slot-1 and is supposed to be repeated in slot-2 and slot-3. However, slot-2 partially overlaps with the cell DRX inactive period 29; and slot-3 fully overlaps with the cell DRX inactive period 29. According to this alternative, the PUSCH is transmitted in slot-1 and, PUSCH Repetition is only based on Slot-1 and Slot-2. Thus, the repetition slots are reduced from K=3 to K=2.
Alt-3 - the PUSCH Repetition number is reduced, i.e., only occupies one or more slots that are not overlapping with the cell DRX inactive period 29. In the example shown in Fig. 10, PUSCH Repetition is only based on Slot-1. Thus, the repetition slots are reduced from K=3 to K=1.

Proposal 7
　　The alternatives discussed above deal with the situation where the first PUSCH repetition is transmitted during the cell DRX active period 31. There may be situations where the first PUSCH repetition overlaps with the cell DRX inactive period 29. Such a scenario is illustrated in Fig. 11 for the slot-5 and slot-6. This causes additional issues as from a PUSCH repetition perspective, the physical layer parameters (e.g., HARQ RV, frequency/time resource allocation, and HARQ process ID selection when different PUSCHs are transmitted) for consecutive slots (e.g., slot-2 and slot-3) are determined based on parameter selection in slot-1.

　　For example, 3GPP specifies an HARQ RV sequence that is to be used for repetitions and is typically of form: {0,2,3,1} where the first RV= 0 is used for the first repetition, RV=2 is used for second repetition and so on. If the UE 3 does not transmit for one or more first repetitions/slots 1 to N, the inventors have realised that the physical layer parameters to be used by the UE 3 in the (N+1)th repetition should be decided without the full knowledge of the physical layer parameters that were supposed to be used for slots 1 to N, had they not overlapped with the cell DRX inactive period 29. The inventors propose the following solutions to this problem:
Option-1: the UE 3 uses the transmission parameters (e.g., frequency resource allocation) associated with (N+1)th repetition for its first transmission (i.e., Slot-7 after the cell DRX inactive period) when the first N repetitions are not used by the UE 3 (i.e., Slot-5 and Slot-6 shown in Fig. 11).
Option-2: UE uses the transmission parameters (e.g., HARQ RV) associated with the 1st repetition for its first actual transmission (i.e., the transmission in Slot-7 after the cell DRX inactive period) when the first N repetitions are not used by the UE 3.
Different options may be used for the determination of different transmission parameters. For example, for frequency resource allocation, Option-1 can be used while for HARQ RV determination, Option-2 can be used.

Proposal 8
　　UEs 3 may be configured with multiple parallel Configuration Grants for different data streams. Referring to Fig. 12, the inventors have realised that procedures are needed to address the situation when there is an overlap between a cell DRX inactive period 29 and at least one slot expressed by a CG transmission occasion (e.g. slot-2/3/4) or a whole period (e.g., the second period), in the case of multiple CG based PUSCH. The inventors propose the following alternatives to handle the situation where uplink data arrives in a UE's transmit buffer (from a higher layer) for transmission to the base station 5 during the cell DRX inactive period (e.g. slot-2 shown in Fig. 12):
Alt-0 - the multiple CG based PUSCH operation ignores the inactive period 29 of the cell DRX (which is what legacy UEs will do).
Alt-1 - the PUSCH based UL transmission is dropped/suspended during the whole period if the period partially or completely falls into the cell DRX inactive period 29 (e.g., the first period and the second period) and the UL transmission is restored when the cell enters its cell DRX active period 31. In this case, the uplink data received in the transmit buffer in slot-2 can be transmitted by the first available CG TO among the multiple CGs in the first period to overlap fully with the cell DRX active period, i.e., slot-9 of CG-1 in the example scenario shown in Fig. 12.
Alt-2 - the PUSCH based UL transmission is dropped/suspended during the whole period if the period completely falls into the cell DRX inactive period 29 (e.g., the second period) and the UL transmission is restored when the cell enters its cell DRX active period 31. In the example illustrated in Figure 12, the uplink data received in the UE's transmit buffer in slot-2 can be transmitted by the first available CG TO among the multiple CGs in the first period as it only partially overlaps with the cell DRX inactive period 29, i.e., by slot-3 of CG-3 in the example scenario shown in Fig. 12.

BSR Report
　　When a UE 3 has data to send to the base station 5 in its transmit buffer, it sends the serving base station a Buffer Status Report (BSR) indicating how much data the UE 3 has to send. The network (e.g. the base station 5) would then allocate resources in the PUSCH to allow the UE 3 to transmit the data within its transmit buffer. However, if the serving cell is in its cell DRX inactive period, then the BSR may be delayed until the cell comes out of its cell DRX inactive period.

　　The UE 3 may have an available grant, but the grant may not be used during the cell DRX inactive period. In this scenario, if the serving cell is in a cell DRX inactive period, the current specifications require the UE 3 to include a BSR into the MAC PDU generated for UL transmission based on the available grant instead of triggering a Scheduling Request (SR) for a dynamic grant (DG), even though the available UL grant might not be useable due to cell DRX. This will delay the sending of the BSR to the base station 5. The inventors propose the following solutions to this problem depending on whether or not SR is active during cell DRX inactive periods.

　　If the SR is not useable during cell DRX inactive periods (as illustrated in Fig. 13), then the BSR is delayed to be reported until the cell transitions from its cell DRX inactive period 29 to its cell DRX active period 31-2. The UE triggers a SR 37 at the start of the cell DRX active period 31-2 to get a dynamic grant (to send the BSR report) from the network (e.g. the base station 5), provided the resources used for transmitting the SR 37 are before the first available Configured Grant resources (in the example shown in Fig. 13 TO 27-4). The UE can then use the dynamic grant (allocated by the base station 5 in response to the SR 37) to send the BSR report if the dynamic grant is scheduled before the first available Configured Grant resources (in the example shown in Fig. 13, CG TO 27-4). Otherwise (i.e., if the first available Configured Grant TO is ahead of the SR resource or the dynamic grant), then the UE 3 can send the BSR report via the first available Configured Grant resources. In the example illustrated in Fig. 13, the SR resource is before the first available CG TO 27-4, and therefore the UE transmits the SR 37 to the base station 5. However, the dynamic grant 39 provided by the base station 5 is delayed until after CG TO 27-4 and therefore, in this example, the UE 3 transmits the BSR 41 to the base station 5 using the CG TO 27-4.

　　If the SR is useable during cell DRX inactive periods (as illustrated in Fig. 14), then the SR to request resources for the BSR is triggered following the availability of the BSR. In the example shown in Fig. 14, the SR 37 is used to request a dynamic grant for transmitting the BSR. The network (e.g. the base station 5), may schedule a dynamic grant which should follow the end of a cell DRX inactive period 29, and the UE can transmit the BSR using the resources granted by the dynamic grant. However, if the resources allocated by the dynamic grant are overly delayed, then the UE can transmit the BSR in the first available CG resources (in this example using CG TO 27-4). Similarly, if the first available CG transmission occasion (TO) following the cell DRX inactive period 29 closely follows the end of the cell DRX inactive period (for example falls within a threshold time period from the start of the active period), then the UE 3 can decide not to transmit the SR 37 for the BSR and instead decide to transmit the BSR at the first available CG TO 27-4.

Dynamic UL Transmission
　　In order for a UE 3 to be awake during the time when the base station 5 may request the UE 3 to retransmit a previous uplink transmission and not before, two timers are defined in 3GPP. The first timer drx-HARQ-RTT-TimerUL (in number of symbols) defines after how long the UE 3 can expect a grant for an uplink re-transmission; and the second timer drx-RetransmissionTimerUL (in number of slots) defines the time duration for which the UE 3 has to be awake to receive the request for uplink re-transmission.. This second timer specifies the maximum number of slots for which the UE 3 should be monitoring the PDCCH when a request for uplink re-transmission is expected. The UE should start the timer drx-HARQ-RTT-TimerUL in the immediate first symbol after transmitting PUSCH. If PUSCH repetition is configured, then this timer is started after the first PUSCH transmission within a bundle of repetitions. Once the drx-HARQ-RTT-TimerUL timer has expired, the UE 3 starts the drx-RetransmissionTimerUL timer in the next symbol and becomes active for the number of slots defined by this second timer. When the UE 3 detects a DL transmission for the corresponding HARQ process, drx-RetransmissionTimerUL is stopped. Fig. 15 illustrates the operation of these timers and the possibility that the UE may become active during a cell DRX inactive period when the base station 5 will not be sending any dynamic grant.

　　In particular, for Uplink PUSCH based initial transmission, if the network (e.g. the base station 5) does not decode the initial transmission when there is any overlapping between the started drx-HARQ-RTT-TimerUL and/or drx-RetransmissionTimerUL and the cell DRX inactive period (as shown in Fig. 16), the expected UL dynamic grant for PUSCH retransmission from the network (e.g. the base station 5) to the UE 3 can be delayed until the cell returns to its Cell DRX active period. To cater for this, the inventors propose that the UE should adjust its own PDCCH monitoring accordingly for power saving. More specifically, and as shown in Fig. 16, the started drx-HARQ-RTT-TimerUL is only stopped at the end of the cell DRX inactive period, if this timer overlaps with the cell DRX inactive period 29. Alternatively, if the drx-HARQ-RTT-TimerUL was not started, this timer can be skipped by the UE, as long as the cell DRX inactive period is larger than the length of drx-HARQ-RTT-TimerUL. In practice, the drx-RetransmissionTimerUL can be started at the start of the cell DRX active period 31, if the drx-RetransmissionTimerUL falls into the cell DRX inactive period 29.

User Equipment
　　Fig. 17 is a schematic block diagram illustrating the main components of a UE 3 as shown in Fig. 1.

　　As shown, the UE 3 has a transceiver circuit 310 that is operable to transmit signals to and to receive signals from a base station 5 via one or more antennas 330 (e.g., comprising one or more antenna elements). The UE 3 has a controller 370 to control the operation of the UE 3. The controller 370 is associated with a memory 390 and is coupled to the transceiver circuit 310. Although not necessarily required for its operation, the UE 3 might, of course, have all the usual functionality of a conventional UE 3 (e.g. a user interface 350, such as a touch screen / keypad / microphone / speaker and/or the like for, allowing direct control by and interaction with a user) and this may be provided by any one or any combination of hardware, software, and firmware, as appropriate. Software may be pre-installed in the memory 390 and/or may be downloaded via the telecommunications network or from a removable data storage device (RMD), for example.

　　The controller 370 is configured to control overall operation of the UE 3 by, in this example, program instructions or software instructions stored within memory 390. As shown, these software instructions include, among other things, an operating system 410, and a communications control module 430.

　　The communications control module 430 is operable to control the communication between the UE 3 and its one or more serving base stations 5 (and other communication devices connected to the base station 5, such as further UEs and/or core network nodes). The communications control module 430 is configured for the overall handling of uplink communications via associated uplink channels (e.g. via a physical uplink control channel (PUCCH), random access channel (RACH), and/or a physical uplink shared channel (PUSCH)) including both dynamic and semi-static signalling (e.g., SRS). The communications control module 430 is also configured for the overall handling of receipt of downlink communications via associated downlink channels (e.g. via a physical downlink control channel (PDCCH) and/or a physical downlink shared channel (PDSCH)) including both dynamic and semi-static signalling (e.g., CSI-RS). The communications control module 430 is responsible, for example: for determining where to monitor for downlink control information (e.g., the location of CSSs / USSs, CORESETs, and associated PDCCH candidates to monitor); for determining the resources to be used by the UE 3 for transmission/reception of UL/DL communications (including interleaved resources and resources subject to frequency hopping); for managing frequency hopping at the UE side; for determining how slots/symbols are configured (e.g., for UL, DL or SBFD communication, or the like); for determining which one or more bandwidth parts are configured for the UE 3; for determining how uplink transmissions should be encoded; for applying any SBFD specific communication configurations appropriately; and the like. The communications control module 430 is configured to control communications in accordance with any of the proposals and options described for dealing with the overlapping of CG TOs and cell DTX/DRX inactive periods. The communications control module 430 includes a cell DRX/DTX configuration 450 which is provided by the serving base station 5 and identifies the cell DRX/DTX inactive and active periods. As those skilled in the art will appreciate, this information is needed by the UE to control its operation in accordance with the above proposals. The communications control module 430 also includes a CG configuration 460 which defines the periodic grants that have been allocated to the UE 3 as well as DG configuration 470 for any dynamic grants that have been allocated to the UE 3. The communications control module 430 also includes a BSR module 480 that is used to control the buffer status reporting and timers 490 used to define the various timings discussed above.

Base Station
　　Fig. 18 is a schematic block diagram illustrating the main components of the base station 5 for the communication system 1 shown in Fig. 1. As shown, the base station 5 has a transceiver circuit 510 for transmitting signals to and for receiving signals from the communication devices (such as UEs 3) via one or more antennas 530 (e.g. a single or multi-panel antenna array / massive antenna), and a core network interface 550 (e.g. comprising the N2, N3 and other reference points/interfaces) for transmitting signals to and for receiving signals from network nodes in the core network 7. Although not shown, the base station 5 may also be coupled to other base stations via an appropriate interface (e.g. the so-called 'Xn' interface in NR). The base station 5 has a controller 570 to control the operation of the base station 5. The controller 570 is associated with a memory 590. Software may be pre-installed in the memory 590 and/or may be downloaded via the communication system 1 or from a removable data storage device (RMD), for example. The controller 570 is configured to control the overall operation of the base station 5 by, in this example, program instructions or software instructions stored within memory 590.

　　As shown, these software instructions include, among other things, an operating system 610 and a communications control module 630.

　　The communications control module 630 is operable to control the communication between the base station 5 and UEs 3 and other network entities that are connected to the base station 5. The communications control module 630 is configured for the overall control of the reception and decoding of uplink communications, via associated uplink channels (e.g. via a physical uplink control channel (PUCCH), a random-access channel (RACH), and/or a physical uplink shared channel (PUSCH)) including both dynamic and semi-static signalling (e.g., SRS). The communications control module 630 is also configured for the overall control of the transmission of downlink communications via associated downlink channels (e.g. via a physical downlink control channel (PDCCH) and/or a physical downlink shared channel (PDSCH)) including both dynamic and semi-static signalling (e.g., CSI-RS). The communications control module 630 is responsible for managing full duplex (e.g., SBFD) communication including, where appropriate, the segregation of UL and DL communication via different physical antenna elements. The communications control module 630 is responsible, for example: for determining where to configure the UE 3 to monitor for downlink control information (e.g., the location of CSSs / USSs, CORESETs, and associated PDCCH candidates to monitor); for determining the resources to be scheduled for UE transmission/reception of UL/DL communications (including interleaved resources and resources subject to frequency hopping); for managing frequency hopping at the base station side; for configuring slots/symbols appropriately (e.g., for UL, DL or SBFD communication, or the like); for configuring one or more bandwidth parts for the UE 3; for providing related configuration signalling to the UE 3; and the like.

　　The communications control module 630 is configured to control communications with the UEs 3 in accordance with any of the proposals and options described above for allocating resources to the UEs to allow them to manage their uplink transmissions whilst the base station transitions between cell DTX/DRX inactive and active periods. The communications control module 630 includes a cell DRX/DTX configuration 650 which the base station broadcasts to UEs it is serving and is used by the base station 5 to define its cell DRX/DTX inactive and active periods. The communications control module 630 also includes CG configurations 660 which defines the periodic grants that the base station has allocated to the UEs it is serving as well as DG configurations 670 for dynamic grants that have been allocated to UEs the base station is serving. The communications control module 630 also includes timers 680 used to define the various timings discussed above.

Modifications and Alternatives
　　As those skilled in the art will appreciate, a number of modifications and alternatives can be made to the above example embodiments whilst still benefiting from the disclosure embodied therein.

　　Whilst the Configured Grant process described above is for the case of New Radio (5G) communication systems, there are other proposals for 5G implementation in an unlicensed frequency band (normally designated as NR-U) and the present disclosure is applicable in this deployment scenario as well. NR-U supports three deployment modes: Carrier Aggregation (where the unlicensed spectrum is used to augment the downstream user plane and control data is transported over the licensed spectrum only); Dual Connectivity (which supports both uplink and downlink user plane traffic over the unlicensed spectrum and again the control data is transported over the licensed spectrum only); and standalone (in which all data transmission including control data is performed within the unlicensed frequency band). One difference between NR-CG and NR-UCG is that in NR-UCG, the UE assumes a negative acknowledgement if it does not receive a positive acknowledgement of receipt for the uplink data from the base station within the period defined by the Configured Grant Timer.

　　As those skilled in the art will appreciate, the timing of the slots/TOs shown in the figures relative to the timing of the cell DRX active and inactive periods is just given for explanation. In practice, the cell DRX inactive and active periods may span many TO periods. Similarly, in many of the attached figures, the gap between adjacent CG TOs is shown to equal the CGRT length. This is not essential as in practice these can be different.

　　It will be appreciated, that whilst cellular communication generation (2G, 3G, 4G, 5G, 6G etc.) specific terminology may be used, in the interests of clarity, to refer to specific communication entities, the technical features described for a given entity are not limited to devices of that specific communication generation. The technical features may be implemented in any functionally equivalent communication entity regardless of any differences in the terminology used to refer to them.

　　In the above description, the UEs and the base station are described for ease of understanding as having a number of discrete functional components or modules. Whilst these modules may be provided in this way for certain applications, for example where an existing system has been modified to implement the disclosure, in other applications, for example in systems designed with the inventive features in mind from the outset, these modules may be built into the overall operating system or code and so these modules may not be discernible as discrete entities.

　　In the above example embodiments, a number of software modules were described. As those skilled in the art will appreciate, the software modules may be provided in compiled or un-compiled form and may be supplied as a signal over a computer network, or on a recording medium. Further, the functionality performed by part, or all of this software may be performed using one or more dedicated hardware circuits. However, the use of software modules is preferred as it facilitates the updating of the base station or the UE in order to update their functionalities.

　　Each controller may comprise any suitable form of processing circuitry including (but not limited to), for example: one or more hardware implemented computer processors; microprocessors; central processing units (CPUs); arithmetic logic units (ALUs); input/output (IO) circuits; internal memories / caches (program and/or data); processing registers; communication buses (e.g. control, data and/or address buses); direct memory access (DMA) functions; hardware or software implemented counters, pointers and/or timers; and/or the like. Various other modifications will be apparent to those skilled in the art and will not be described in further detail here.

　　The base station may comprise a 'distributed' base station having a central unit 'CU' and one or more separate distributed units (DUs).

　　The User Equipment (or "UE", "mobile station", "mobile device" or "wireless device") in the present disclosure is an entity connected to a network via a wireless interface.

　　It should be noted that the present disclosure is not limited to a dedicated communication device and can be applied to any device having a communication function as explained in the following paragraphs.

　　The terms "User Equipment" or "UE" (as the term is used by 3GPP), "mobile station", "mobile device", and "wireless device" are generally intended to be synonymous with one another, and include standalone mobile stations, such as terminals, cell phones, smart phones, tablets, cellular IoT devices, IoT devices, and machinery. It will be appreciated that the terms "mobile station" and "mobile device" also encompass devices that remain stationary for a long period of time.

　　A UE may, for example, be an item of equipment for production or manufacture and/or an item of energy related machinery (for example equipment or machinery such as: boilers; engines; turbines; solar panels; wind turbines; hydroelectric generators; thermal power generators; nuclear electricity generators; batteries; nuclear systems and/or associated equipment; heavy electrical machinery; pumps including vacuum pumps; compressors; fans; blowers; oil hydraulic equipment; pneumatic equipment; metal working machinery; manipulators; robots and/or their application systems; tools; molds or dies; rolls; conveying equipment; elevating equipment; materials handling equipment; textile machinery; sewing machines; printing and/or related machinery; paper converting machinery; chemical machinery; mining and/or construction machinery and/or related equipment; machinery and/or implements for agriculture, forestry and/or fisheries; safety and/or environment preservation equipment; tractors; precision bearings; chains; gears; power transmission equipment; lubricating equipment; valves; pipe fittings; and/or application systems for any of the previously mentioned equipment or machinery etc.).

　　A UE may, for example, be an item of transport equipment (for example transport equipment such as: rolling stocks; motor vehicles; motorcycles; bicycles; trains; buses; carts; rickshaws; ships and other watercraft; aircraft; rockets; satellites; drones; balloons etc.). A UE may, for example, be an item of information and communication equipment (for example information and communication equipment such as: electronic computer and related equipment; communication and related equipment; electronic components etc.).

　　A UE may, for example, be a refrigerating machine, a refrigerating machine applied product, an item of trade and/or service industry equipment, a vending machine, an automatic service machine, an office machine or equipment, a consumer electronic and electronic appliance (for example a consumer electronic appliance such as: audio equipment; video equipment; a loud speaker; a radio; a television; a microwave oven; a rice cooker; a coffee machine; a dishwasher; a washing machine; a dryer; an electronic fan or related appliance; a cleaner etc.).

　　A UE may, for example, be an electrical application system or equipment (for example an electrical application system or equipment such as: an x-ray system; a particle accelerator; radio isotope equipment; sonic equipment; electromagnetic application equipment; electronic power application equipment etc.).

　　A UE may, for example, be an electronic lamp, a luminaire, a measuring instrument, an analyser, a tester, or a surveying or sensing instrument (for example a surveying or sensing instrument such as: a smoke alarm; a human alarm sensor; a motion sensor; a wireless tag etc.), a watch or clock, a laboratory instrument, optical apparatus, medical equipment and/or system, a weapon, an item of cutlery, a hand tool, or the like.

　　A UE may, for example, be a wireless-equipped personal digital assistant or related equipment (such as a wireless card or module designed for attachment to or for insertion into another electronic device (for example a personal computer, electrical measuring machine)).

　　A UE may be a device or a part of a system that provides applications, services, and solutions described below, as to "internet of things (IoT)", using a variety of wired and/or wireless communication technologies.

　　Internet of Things devices (or "things") may be equipped with appropriate electronics, software, sensors, network connectivity, and/or the like, which enable these devices to collect and exchange data with each other and with other communication devices. IoT devices may comprise automated equipment that follow software instructions stored in an internal memory. IoT devices may operate without requiring human supervision or interaction. IoT devices might also remain stationary and/or inactive for a long period of time. IoT devices may be implemented as a part of a (generally) stationary apparatus. IoT devices may also be embedded in non-stationary apparatus (e.g. vehicles) or attached to animals or persons to be monitored/tracked.

　　It will be appreciated that IoT technology can be implemented on any communication devices that can connect to a communications network for sending/receiving data, regardless of whether such communication devices are controlled by human input or software instructions stored in memory.

　　It will be appreciated that IoT devices are sometimes also referred to as Machine-Type Communication (MTC) devices or Machine-to-Machine (M2M) communication devices. It will be appreciated that a UE may support one or more IoT or MTC applications. Some examples of MTC applications are listed in the following table. This list is not exhaustive and is intended to be indicative of some examples of machine type communication applications.

　　Applications, services, and solutions may be an MVNO (Mobile Virtual Network Operator) service, an emergency radio communication system, a PBX (Private Branch eXchange) system, a PHS/Digital Cordless Telecommunications system, a POS (Point of sale) system, an advertise calling system, an MBMS (Multimedia Broadcast and Multicast Service), a V2X (Vehicle to Everything) system, a train radio system, a location related service, a Disaster/Emergency Wireless Communication Service, a community service, a video streaming service, a femto cell application service, a VoLTE (Voice over LTE) service, a charging service, a radio on demand service, a roaming service, an activity monitoring service, a telecom carrier/communication NW selection service, a functional restriction service, a PoC (Proof of Concept) service, a personal information management service, an ad-hoc network/DTN (Delay Tolerant Networking) service, etc.

　　Further, the above-described UE categories are merely examples of applications of the technical ideas and example embodiments described in the present document. Needless to say, these technical ideas and example embodiments are not limited to the above-described UE and various modifications can be made thereto.

　　Various other modifications will be apparent to those skilled in the art and will not be described in further detail here.

　　For example, the whole or part of the exemplary embodiments disclosed above can be described as, but not limited to, the following supplementary notes.
　　　　(Supplementary note 1)
　　A method performed by a user equipment, UE, the method comprising:
　　receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node;
　　receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　transmitting first uplink data to the access network node in a first TO of said plurality of TOs at a timing when said access network node is in said active period;
　　wherein the UE is configured to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO;
　　determining from the configured grant and said first information if the access network node is in said inactive period during said second TO; and
　　in a case where the access network node is in said inactive period during said second TO, delaying, or stopping, sending of said first retransmission of the first uplink data.
　　　　(Supplementary note 2)
　　The method according to supplementary note 1, wherein in a case where the access network node is in said inactive period during said second TO, delaying sending of said first retransmission of the first uplink data in a case where the UE has not received an acknowledgement of receipt of the first uplink data.
　　　　(Supplementary note 3)
　　The method according to supplementary note 1, wherein in a case where the access network node is in said inactive period during said second TO, stopping sending of said first retransmission of the first uplink data in a case where the UE has received an acknowledgement of receipt of the first uplink data.
　　　　(Supplementary note 4)
　　The method according to any one of supplementary notes 1 to 3, wherein the UE is configured to transmit a second retransmission of the first uplink data to the access network node in a third TO that is after the second TO; and wherein in the case that the second TO partially overlaps with said inactive period and partially overlaps with said active period, sending the first retransmission in the second TO and in a case where the access network node is in said inactive period during said third TO, delaying, or stopping, sending of said second retransmission of the first uplink data.
　　　　(Supplementary note 5)
　　The method according to any one of supplementary notes 1 to 4, further comprising monitoring a first physical downlink control channel, PDCCH, occasion that follows the inactive period of the access network node to acquire a dynamic grant for an uplink transmission.
　　　　(Supplementary note 6)
　　The method according to supplementary note 5, wherein in the case that a dynamic grant is acquired for the UE, transmitting uplink data to the access network node using resources allocated by the dynamic grant.
　　　　(Supplementary note 7)
　　The method according to supplementary note 6, wherein the uplink data transmitted using the dynamic grant comprises a retransmission of said first uplink data.
　　　　(Supplementary note 8)
　　The method according to any one of supplementary notes 1 to 7, further comprising transmitting a retransmission of said first uplink data in a first available TO that overlaps with the active period of the access network node following an inactive period of the access network node.
　　　　(Supplementary note 9)
　　The method according to any one of supplementary notes 1 to 8, further comprising running a CG Retransmission Timer, CGRT, and in the event that the first uplink data transmission is not acknowledged by the access network node before the start of the inactive period, stopping or extending the CGRT and not autonomously retransmitting the first uplink data in a subsequent TO.
　　　　(Supplementary note 10)
　　The method according to supplementary note 9, wherein if a duration of the CGRT plus a duration of the inactive period of the access network node is larger than a delay budget for the first uplink data, stopping further retransmission of the first uplink data and transmitting second uplink data in a TO following the end of the inactive period.
　　　　(Supplementary note 11)
　　The method according to supplementary note 9, comprising automatically disabling CGRT based retransmissions during said inactive period.
　　　　(Supplementary note 12)
　　The method according to any one of supplementary notes 1 to 11, further comprising running a CG Timer, CGT, for limiting a number repetitions that are transmitted of said first data; and stopping or suspending the CGT during said inactive period of the access network node.
　　　　(Supplementary note 13)
　　The method according to supplementary note 12, further comprising restarting or recovering the CGT at the end of the inactive period of the access network node.
　　　　(Supplementary note 14)
　　The method according to supplementary note 12, comprising automatically disabling the CRT based retransmissions during said inactive period.
　　　　(Supplementary note 15)
　　The method according to any one of supplementary notes 1 to 14, further comprising receiving second information from the access network node indicating that the UE should perform a retransmission of the first uplink data in a TO that overlaps with said inactive period, and in response to receiving said second information, transmitting a retransmission of said first uplink data during the inactive period of the access network node.
　　　　(Supplementary note 16)
　　The method according to supplementary note 15, wherein said second information comprises a UE specific drx-InactivityTimer.
　　　　(Supplementary note 17)
　　The method according to any one of supplementary notes 1 to 16, wherein the first uplink data is transmitted on a Physical Uplink Shared Channel, PUSCH, and the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots.
　　　　(Supplementary note 18)
　　The method according to supplementary note 17, wherein the UE drops or suspends PUSCH repetition based uplink transmission during the inactive period of the access network node.
　　　　(Supplementary note 19)
　　The method according to supplementary note 17, wherein the UE reduces a repetition number of the PUSCH for any time slot that fully overlaps with the inactive period of the access network node.
　　　　(Supplementary note 20)
　　The method according to supplementary note 17, wherein the UE reduces a repetition number of the PUSCH for any time slot that fully overlaps and that partially overlaps with the inactive period of the access network node.
　　　　(Supplementary note 21)
　　The method according to any one of supplementary notes 17 to 20, comprising receiving from the access network node a plurality of Configured Grants, CGs, that each defines a plurality of periodic uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, and wherein the plural CGs configure the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node.
　　　　(Supplementary note 22)
　　The method according to supplementary note 21, wherein the UE drops or suspends PUSCH based uplink transmission during a period if any time slot within that period fully overlaps with the inactive period of the access network node.
　　　　(Supplementary note 23)
　　The method according to supplementary note 22, wherein if a CG period partially overlaps with the inactive period of the access network node, the UE transmits the uplink data in a first available CG TO time slot of the CG period that overlaps with the inactive period of the access network node.
　　　　(Supplementary note 24)
　　The method according to supplementary note 21, wherein the UE drops or suspends PUSCH based uplink transmission during a period if any time slot within that period fully overlaps and if any time slot within that period partially overlaps with the inactive period of the access network node.
　　　　(Supplementary note 25)
　　The method according to supplementary note 17, wherein the UE reduces a repetition number of the PUSCH for any time slot that fully overlaps and that partially overlaps with the inactive period of the access network node.
　　　　(Supplementary note 26)
　　The method according to supplementary note 25, wherein the UE transmits the uplink data in a first available CG TO time slot of a CG period that fully overlaps with a next active period of the access network node.
　　　　(Supplementary note 27)
　　The method according to any one of supplementary notes 1 to 26, comprising receiving a Buffer Status Report, BSR, for transmission to the access network node during the inactive period of the access network node; and transmitting a Scheduling Request, SR, to the access network node to obtain a Dynamic Grant, DG, of uplink resources on which to transmit the BSR.
　　　　(Supplementary note 28)
　　The method according to supplementary note 27, comprising receiving the DG from the access network node and transmitting the BSR on the resources granted by the DG in a case where those resources are before a next available CG TO.
　　　　(Supplementary note 29)
　　The method according to supplementary note 27 or 28, comprising transmitting the BSR on the resources granted by the next available CG TO in a case where the resources granted by the DG are after the resources granted by the next available CG TO.
　　　　(Supplementary note 30)
　　The method according to any one of supplementary notes 27 to 29, further comprising determining when the access network node transitions from the inactive period to the active period and in response to such transition, transmitting the SR to the access network node.
　　　　(Supplementary note 31)
　　The method according to any one of supplementary notes 27 to 30, further comprising determining when the access network node transitions from the inactive period to the active period and a timing of a next available CG TO during the next access node active period and deciding not to transmit the SR to the access network node if the next available CG TO during the next access node active period falls within a threshold time period of a start of the access network node active period.
　　　　(Supplementary note 32)
　　A method performed by a user equipment, UE, the method comprising:
　　receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, wherein the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node;
　　receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　determining from the configured grant and said first information if the access network node is in said inactive period during any time slot configured for PUSCH transmission;
in the case where the a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, the UE uses at least one transmission parameter associated with the (N+1)th repetition to transmit the first repetition of the PUSCH in the (N+1)th time slot and/or the UE uses at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to transmit the first repetition of the PUSCH in the (N+1)th time slot.
　　　　(Supplementary note 33)
　　A method performed by a user equipment, UE, the method comprising:
configuring a first timer indicating how long after transmitting uplink data to an access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data;
configuring a second timer that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data;
receiving from an access network node a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node;
transmitting first uplink data to the access network node using the one or more resources;
receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　determining if the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node; and
　　in a case where the first timer has started, extending the first timer to run until the end of the inactive period of the access network node and starting the second timer once the access network node is in the active period following the end of the inactive period.
　　　　(Supplementary note 34)
　　The method according to supplementary note 33, wherein in a case where the first timer has not started, skipping the running of the first timer and starting the second timer once the access network node is in the active period following the end of the inactive period.
　　　　(Supplementary note 35)
　　The method according to supplementary note 33 or 34, wherein the UE sleeps in a period between transmitting the first uplink data and the running of the second timer.
　　　　(Supplementary note 36)
　　A method performed by an access network node, the method comprising:
　　transmitting to a User Equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node;
　　transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　receiving first data corresponding to first uplink data transmitted from the UE in a first TO of said plurality of TOs at a timing when said access network node is in said active period;
　　wherein the CG configures resources for the UE to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO;
　　wherein in a case where the second TO is in said inactive period of the access network node and the access network node has not acknowledged receipt of the first uplink data: i) maintaining the first data in an uplink buffer associated with the UE, ii) receiving, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recovering the first uplink data using the first data and the second data.
　　　　(Supplementary note 37)
　　The method according to supplementary note 36, wherein in a case where the second TO is in said inactive period of the access network node and the access network node has acknowledged receipt of the first uplink data, providing the first uplink data to higher layers and flushing the uplink buffer associated with the UE.
　　　　(Supplementary note 38)
　　The method according to supplementary note 36 or 37, wherein in the case that the second TO partially overlaps with said inactive period and partially overlaps with said active period, receiving the first retransmission in the second TO.
　　　　(Supplementary note 39)
　　The method according to any one of supplementary notes 36 to 38, further comprising providing a dynamic grant to the UE for an uplink transmission and receiving uplink data from the UE using resources allocated by the dynamic grant.
　　　　(Supplementary note 40)
　　The method according to supplementary note 39, wherein the uplink data transmitted using the dynamic grant comprises a retransmission of said first uplink data.
　　　　(Supplementary note 41)
　　The method according to any one of supplementary notes 36 to 40, further comprising receiving a retransmission of said first uplink data in a first available TO that overlaps with an active period of the access network node following an inactive period of the access network node.
　　　　(Supplementary note 42)
　　The method according to any one of supplementary notes 36 to 41, further comprising transmitting second information to the UE indicating that the UE should perform a retransmission of the first uplink data in a TO that overlaps with said inactive period, and receiving a retransmission of said first uplink data during the inactive period of the access network node.
　　　　(Supplementary note 43)
　　The method according to supplementary note 42, wherein said second information comprises a UE specific drx-InactivityTimer.
　　　　(Supplementary note 44)
　　The method according to any one of supplementary notes 36 to 43, wherein the first uplink data is received on a Physical Uplink Shared Channel, PUSCH, and the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots.
　　　　(Supplementary note 45)
　　The method according to supplementary note 44, comprising transmitting to the UE a plurality of Configured Grants, CGs, that each defines a plurality of periodic uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, and wherein the plural CGs configure the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node.
　　　　(Supplementary note 46)
　　A method according to supplementary note 45, wherein if a CG period partially overlaps with the inactive period of the access network node, receiving uplink data in a first available CG TO time slot of the CG period that overlaps with the inactive period of the access network node.
　　　　(Supplementary note 47)
　　The method according to any one of supplementary notes 36 to 46, comprising receiving a Scheduling Request, SR, from the UE to obtain a Dynamic Grant, DG, of uplink resources on which to transmit a Buffer Status Report, BSR.
　　　　(Supplementary note 48)
　　The method according to supplementary note 47, comprising transmitting the DG to the UE and receiving the BSR on the resources granted by the DG in a case where those resources are before a next available CG TO.
　　　　(Supplementary note 49)
　　The method according to supplementary note 48, comprising receiving the BSR on the resources granted by the next available CG TO in a case where the resources granted by the DG are after the resources granted by the next available CG TO.
　　　　(Supplementary note 50)
　　A method performed by an access network node, the method comprising:
　　transmitting to a user equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, to the access network node and wherein the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node;
　　transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
in the case where a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, receiving a first repetition of the PUSCH from the UE in the (N+1)th time slot, wherein the access network node uses at least one transmission parameter associated with the (N+1)th repetition to receive the first repetition of the PUSCH in the (N+1)th time slot and/or the access network node uses at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to receive the first repetition of the PUSCH in the (N+1)th time slot.
　　　　(Supplementary note 51)
　　A method performed by an access network node, the method comprising:
transmitting first timer data to a user equipment, UE, that configures a first timer in the UE indicating how long after transmitting uplink data to the access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data;
transmitting second timer data to the UE that configures a second timer in the UE that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data;
transmitting to the UE a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node;
receiving first data corresponding to first uplink data transmitted from the UE using the one or more resources;
transmitting third data indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; and
　　wherein in a case where the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node: i) maintaining the first data in an uplink buffer associated with the UE, ii) receiving, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recovering the first uplink data using the first data and the second data.
　　　　(Supplementary note 52)
　　A user equipment, UE, comprising:
　　means for receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node;
　　means for receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　means for transmitting first uplink data to the access network node in a first TO of said plurality of TOs at a timing when said access network node is in said active period;
　　wherein the UE is configured to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO;
　　means for determining from the configured grant and said first information if the access network node is in said inactive period during said second TO; and
　　in a case where the access network node is in said inactive period during said second TO, the UE is configured to delay, or stop, sending said first retransmission of the first uplink data.
　　　　(Supplementary note 53)
　　A user equipment, UE, comprising:
　　means for receiving from an access network node a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, and the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node;
　　means for receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　means for determining from the configured grant and said first information if the access network node is in said inactive period during any time slot configured for PUSCH transmission;
in the case where the a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, the UE is configured to use at least one transmission parameter associated with the (N+1)th repetition to transmit the first repetition of the PUSCH in the (N+1)th time slot and/or the UE is configured to use at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to transmit the first repetition of the PUSCH in the (N+1)th time slot.
　　　　(Supplementary note 54)
　　A user equipment, UE, comprising:
means for configuring a first timer indicating how long after transmitting uplink data to an access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data;
means for configuring a second timer that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data;
means for receiving from an access network node a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node;
means for transmitting first uplink data to the access network node using the one or more resources;
means for receiving first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　means for determining if the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node; and
　　in a case where the first timer has started, the UE is configured to extend the first timer to run until the end of the inactive period of the access network node and to start the second timer once the access network node is in the active period following the end of the inactive period.
　　　　(Supplementary note 55)
　　An access network node comprising:
　　means for transmitting to a User Equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data to the access network node;
　　means for transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
　　means for receiving first data corresponding to first uplink data transmitted from the UE in a first TO of said plurality of TOs at a timing when said access network node is in said active period;
　　wherein the CG configures resources for the UE to transmit a first retransmission of the first uplink data to the access network node in a second TO that is after the first TO;
　　wherein in a case where the second TO is in said inactive period of the access network node and the access network node has not acknowledged receipt of the first uplink data, the access network node is configured to: i) maintain the first data in an uplink buffer associated with the UE, ii) receive, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recover the first uplink data using the first data and the second data.
　　　　(Supplementary note 56)
　　An access network node comprising:
　　means for transmitting to a user equipment, UE, a Configured Grant, CG, that defines a plurality of uplink Transmission Occasions, TOs, for the UE to transmit data on a Physical Uplink Shared Channel, PUSCH, to the access network node and wherein the CG configures the UE to transmit plural repetitions of the PUSCH over consecutive time slots to the access network node;
　　means for transmitting first information indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE;
in the case where a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the inactive period, the access network node is configured to receive a first repetition of the PUSCH from the UE in the (N+1)th time slot, and is configured to use at least one transmission parameter associated with the (N+1)th repetition to receive the first repetition of the PUSCH in the (N+1)th time slot and/or the access network node is configured to use at least one transmission parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot, to receive the first repetition of the PUSCH in the (N+1)th time slot.
　　　　(Supplementary note 57)
　　An access network node, the method comprising:
means for transmitting first timer data to a user equipment, UE, that configures a first timer in the UE indicating how long after transmitting uplink data to the access network node the UE can expect to wait before receiving a request from the access network node for the UE to retransmit the first uplink data;
means for transmitting second timer data to the UE that configures a second timer in the UE that runs after the first timer and which indicates a time period over which the UE should be awake to monitor for said request from the access network node to retransmit the uplink data;
means for transmitting to the UE a Dynamic Grant, DG, that allocates one or more resources for the UE to use to transmit uplink data to the access network node;
means for receiving first data corresponding to first uplink data transmitted from the UE using the one or more resources;
means for transmitting third data indicating a discontinuous reception, DRX, configuration of the access network node defining an active period in which the access network node is supposed to be active and configured to communicate with the UE and an inactive period in which the access network node is supposed to be inactive and configured not to communicate with the UE; and
　　wherein in a case where the first timer and/or the second timer in respect of the transmitted first uplink data overlaps with said inactive period of the access network node, the access network node is configured to: i) maintain the first data in an uplink buffer associated with the UE, ii) receive, when the access network node returns to the active period, second data corresponding to a retransmission of the first uplink data from the UE, and iii) recover the first uplink data using the first data and the second data.

　　This application is based upon and claims the benefit of priority from Great Britain Patent Application No. 2304882.0, filed on March 31, 2023, the disclosure of which is incorporated herein in its entirety by reference.

1 COMMUNICATION SYSTEM
3 USER EQUIPMENT
5 BASE STATION
7 CORE NETWORK
9 CELL
10 CONTROL PLANE FUNCTIONS
11 USER PLANE FUNCTIONS
20 EXTERNAL DATA NETWORK
310 TRANSCEIVER CIRCUIT
330 ANTENNA
350 USER INTERFACE
370 CONTROLLER
390 MEMORY
410 OPERATING SYSTEM
430 COMMUNICATIONS CONTROL MODULE
450 CELL DTX/DRX CONFIGURATION
460 CG CONFIGURATION
470 DG CONFIGURATION
480 BSR MODULE
490 TIMERS
510 TRANSCEIVER CIRCUIT
530 ANTENNA
550 CORE NETWORK INTERFACE
570 CONTROLLER
590 MEMORY
610 OPERATING SYSTEM
630 COMMUNICATIONS CONTROL MODULE
650 CELL DTX/DRX CONFIGURATION
660 UE CG CONFIGURATION
670 UE DG CONFIGURATION
680 TIMERS

Claims

　　A method performed by a user equipment, UE, the method comprising:
　　configuring at least one configured grant, CG, which specifies at least one transmission occasion, TO, for the UE to transmit data to an access network node without scheduling grants;
　　determining that one of the at least one TO overlaps a cell discontinuous reception, DRX, inactive period of a cell of the access network node; and
　　delaying, or stopping, transmitting data on the cell, in at least a part of one or more of the at least one TO each of which overlaps the cell DRX inactive period.
　　The method according to claim 1, wherein
　　in a case where reception of initial data transmitted in another TO before the one of the at least one TO which overlaps the cell DRX inactive period is acknowledged by the access network node, the delaying, or the stopping, transmitting the data is performed.
　　The method according to claim 1 or 2, further comprising:
　　in a case where reception of initial data transmitted in another TO before the one of the at least one TO which overlaps the cell DRX inactive period is acknowledged by the access network node, receiving, from the access network node, information indicating the delaying, or the stopping, transmitting the data, in a message indicating acknowledgement of the reception of the initial data.
　　The method according to any one of claims 1 to 3, further comprising:
　　monitoring a first physical downlink control channel occasion following the cell DRX inactive period, to acquire a scheduling grant to transmit the data.
　　The method according to any one of claims 1 to 4, wherein
　　in a case where the one of the at least one TO is completely covered by the cell DRX inactive period, the delaying, or the stopping, transmitting the data, is performed.
　　The method according to claim 1, wherein
　　in a case where reception of initial data transmitted in another TO before the one of the at least one TO which overlaps the cell DRX inactive period is not acknowledged by the access network node, a scheduling grant to retransmit the initial data is schedued following the cell DRX inactive period.
　　The method according to claim 1, further comprising:
　　in a case where reception of initial data transmitted in another TO before the one of the at least one TO which overlaps the cell DRX inactive period is not acknowledged by the access network node, retransmitting the initial data in one of the at least one TO following the cell DRX inactive period.
　　The method according to claim 1, further comprising:
　　in a case where configured grant downlink feedback information, CG-DFI corresponding to initial data transmitted in another TO before the one of the at least one TO which overlaps the cell DRX inactive period is not received from the access network node, stopping or suspending a configuration grant retransmission timer.
　　The method according to claim 8, further comprising:
　　in a case where a duration based on the configuration grant retransmission timer and the cell DRX inactive period is equal to or smaller than a delay budget value, delaying, or stopping, autonomous retransmission of the initial data on the cell, in at least a part of one or more of the at least one TO each of which overlaps the cell DRX inactive period.
　　The method according to claim 8 or 9, further comprising:
　　in a case where the CG-DFI corresponding to the initial data transmitted in another TO before the one of the at least one TO which overlaps the cell DRX inactive period is not received from the access network node:
　　　　stopping or suspending a configured grant timer; and
　　　　performing the autonomous retransmission of the initial data on the cell, in one of the at least one TO following the cell DRX inactive period.
　　The method according to claim 10, wherein
　　data other than the initial data is not transmitted in the one of the at least one TO following the cell DRX inactive period.
　　The method according to claim 10 or 11, further comprising:
　　resuming or restarting the configured grant timer upon an expiry of the cell DRX inactive period or the autonomous retransmission of the initial data.
　　The method according to claim 1, further comprising:
　　disabling a retransmission operation using a configured grant transmission timer and a configured grant timer during a cell DRX operation by the access network node.
　　The method according to claim 1, further comprising:
　　in a case where reception of initial data transmitted in another TO before the one of the at least one TO which overlaps the cell DRX inactive period is not acknowledged by the access network node:
　　　　receiving, from the access network node, information to cause the UE to start a drx-inactivitytimer to retransmit the initial data; and
　　　　retransmitting the initial data in one of the at least one TO following the receiving the information.
　　The method according to any one of claims 1 to 14, wherein
　　the configuring is performed by configuring the at least one CG to transmit a plurality of repetitions of a physical uplink shared chanel, PUSCH, over a plurality of time slots, to the access network node, and
　　the determining is performed by determining that one of the time slots overlaps the cell DRX inactive period of the cell of the access network node; and
　　the delaying or the stopping is performed by delaying, or stopping, transmitting repetition of the PUSCH on the cell, in at least a part of one or more of the time slots each of which overlaps the cell DRX inactive period.
　　The method according to claim 15, wherein
　　the delaying or the stopping is performed by delaying, or stopping, transmitting repetition of the PUSCH on the cell, in any of the time slots each of which fully overlaps with the cell DRX inactive period.
　　The method according to claim 15, wherein
　　the delaying or the stopping is performed by delaying, or stopping, transmitting repetition of the PUSCH on the cell, in any of the time slots each of which fully or partially overlaps with the cell DRX inactive period.
　　The method according to any one of claims 15 to 17, further comprising:
　　in the case where a first N time slots corresponding to a first N repetitions of the PUSCH overlap with the cell DRX inactive period:
　　　　using at least one parameter associated with the (N+1)th repetition to transmit a first repetition of the PUSCH in the (N+1)th time slot; and/or
　　　　using at least one parameter associated with the first repetition of the PUSCH that should have been transmitted in the first time slot,
　　to transmit the first repetition of the PUSCH in the (N+1)th time slot.
　　The method according to any one of claims 1 to 18, further comprising:
　　transmitting a buffer status report using either:
　　　　a scheduling grant obtained by a scheduling request which is transmitted following the the cell DRX inactive period, or
　　　　one of the at least one CG following the the cell DRX inactive period.
　　The method according to any one of claims 1 to 18, further comprising:
　　transmitting a buffer status report using a scheduling grant obtained by a scheduling request which is transmitted during the the cell DRX inactive period.
　　A method performed by an access network node, the method comprising:
　　configuring a user equipment with at least one configured grant, CG, which specifies at least one transmission occasion, TO, for the UE to transmit data to the access network node without scheduling grants, and
　　wherein in a case where one of the at least one TO overlaps a cell discontinuous reception, DRX, inactive period of a cell of the access network node, transmitting, by the UE, data on the cell, in at least a part of one or more of the at least one TO each of which overlaps the cell DRX inactive period, is delayed or stopped.
　　A user equipment, UE comprising:
　　means for configuring at least one configured grant, CG, which specifies at least one transmission occasion, TO, for the UE to transmit data to an access network node without scheduling grants;
　　means for determining that one of the at least one TO overlaps a cell discontinuous reception, DRX, inactive period of a cell of the access network node; and
　　means for delaying, or stopping, transmitting data on the cell, in at least a part of one or more of the at least one TO each of which overlaps the cell DRX inactive period.
　　An access network node comprising:
　　means for configuring a user equipment with at least one configured grant, CG, which specifies at least one transmission occasion, TO, for the UE to transmit data to the access network node without scheduling grants, and
　　wherein in a case where one of the at least one TO overlaps a cell discontinuous reception, DRX, inactive period of a cell of the access network node, transmitting, by the UE, data on the cell, in at least a part of one or more of the at least one TO each of which overlaps the cell DRX inactive period, is delayed or stopped.