GB2624031A

GB2624031A - Communication system

Info

Publication number: GB2624031A
Application number: GB2216500.5A
Authority: GB
Inventors: Deogun Pravjyot
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2022-11-04
Filing date: 2022-11-04
Publication date: 2024-05-08
Also published as: GB202216500D0; WO2024095870A1

Abstract

The present disclosure relates to a method performed by an access network node for communicating with a user equipment, UE, the method comprising transmitting, to the UE, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication. UL subband configuration information is then transmitted to the UE comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain. The access network node then receives from the UE an uplink transmission in an uplink subband. The broadcast transmission may comprise a synchronisation signal block, SSB.

Description

Intellectual Property Office Application No GI32216500.5 RTM Date:9 May 2023 The following terms are registered trade marks and should be read as such wherever they occur in this document: 3 GP P Intellectual Property Office is an operating name of the Patent Office www.gov.uk/ipo Communication System The present invention relates to a communication system. The invention 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 invention has particular, although not necessarily exclusive relevance to, improved apparatus and methods that support full duplex communication and uplink subbands in time division duplex (TDD) communication bands.

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 '1.1E') 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.

In the current 5G architecture, for example, the gNB structure may be split into two parts known as the Central Unit (CU) and the Distributed Unit (DU), connected by an Fl interface. This enables the use of a 'split' architecture, whereby the, typically 'higher', CU layers (for example, but not necessarily or exclusively), PDCP and the, typically 'lower', DU layers (for example, but not necessarily or exclusively, RLC/MAC/PHY) to be implemented separately. Thus, for example, the higher layer CU functionality for a number of gNBs may be implemented centrally (for example, by a single processing unit, or in a cloud-based or virtualised system), whilst retaining the lower layer DU functionality locally, in each gNB.

For simplicity, the present application will use the term mobile device, user device, or UE to refer to any communication device that is able to connect to the core network via one or more base stations. Although the present application may refer to mobile devices in the description, it will be appreciated that the technology described can be implemented on any communication devices (mobile and/or generally stationary) 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.

Historically, communication systems have employed two core duplex schemes -frequency division duplex (FDD) and time division duplex (TDD). In FDD the frequency domain resource is split between downlink (DL) and uplink (UL) whereas in TDD the time domain resource is split between DL and UL.

The appropriate duplex scheme to be used in a given scenario is broadly spectrum dependent, albeit with some overlap. Where lower frequency bands are used for communication, paired spectrum UL and DL resource allocations are generally employed and hence FDD is used. In contrast, for higher frequency bands the use of unpaired spectrum, and hence TDD, is becoming increasingly prevalent. Thus, TDD is widely used in commercial NR deployments. Given the significantly higher carrier frequencies supported by 5G, and that will be supported by future communication generations (6G and beyond) as compared to earlier communication generations, improved techniques for providing efficient use of unpaired spectrum are, and will continue to be, increasingly critical.

However, allocation of too limited a time duration for the UL in TDD carriers has the potential to result in reduced coverage, increased latency, and reduced capacity.

Full duplex (FD) operation, involving sharing both frequency domain and time domain resources between the UL and the DL, within the bandwidth of a conventional TDD carrier, represents one way in which improvements may be achievable over conventional TDD performance. Accordingly, enhancements to implement full duplex operation at the gNB, within TDD carriers, are currently being developed -currently with no restriction on the possible frequency ranges used for such FD operation. At present half duplex operation within TDD carriers is still envisaged for the UE, although full duplex UE operation remains an option for the future. The use of FD has, however, the potential to cause serious interference issues, both at the base station and at the UE, which are difficult to address.

There are a number of possible FD implementations that can be implemented on TDD carriers including, for example, subband non-overlapping, subband overlapping, full overlapping.

Referring to Figs. 1 to 4, in subband non-overlapping FD ('SBFD', also referred to as cross division duplex (XDD)), non-overlapping UL and DL subbands may be configured in the TDD carrier (as seen in the general case illustrated in Fig. 1. As seen in Figs. 1 to 4 each subband comprises a respective relatively 'narrow' frequency band having a bandwidth that extends only part of the full available bandwidth within the current TDD carrier that is configured for communication in the associated cell. A base station can thus perform simultaneous (full duplex) transmission and reception at the same time, in different respective non-overlapping subbands, for different UEs.

Fig. 2) shows a particular example in which only one dedicated DL subband and one dedicated UL subband are configured in the TDD carrier. Fig. 3 shows an example in which, from the first slot to the fourth slot, full duplex operation is active where an UL subband is present in the centre of the frequency band and two DL subbands are present at either side of the DL subband. In the fifth slot, the base station uses legacy TDD operation (i.e. entire frequency band is used only for UL). Fig. 4 shows an example in which, from the first slot to the fifth slot, full duplex operation is active. In the first four slots an UL subband is present in the centre of the frequency band and two DL subbands are present at either side of the DL subband. In the fifth slot a complementary UL/DL configuration is present compared to the first four slots.

In subband overlapping FD, UL and DL may be configured in a similar way to subband non-overlapping FD, but the different subbands are allowed to overlap in frequency.

In full overlapping FD, the entire available bandwidth may be used for UL or DL transmissions.

One of the key benefits of SBFD is increased UL coverage because SBFD makes it easier to take advantage of multi-slot UL repetitions due to an increased number of consecutive UL occasions in SBFD. Currently, therefore, focus is on the development of techniques for implementing subband non-overlapping FD operation and potential related enhancements for dynamic or flexible TDD. It will be appreciated, however, that other FD implementations remain an option for the future and enhancements envisaged for sub-band non-overlapping FD may have benefits in other FD schemes.

Wien implementing such full duplex schemes there are a number of considerations that need to be taken into account. Among the considerations that are particularly relevant for SBFD (and other full duplex schemes), for example, is the need to avoid, or at least minimise, any impact on the operation of existing (legacy') UEs that were designed/implemented prior to the implementation of any such duplex schemes.

Moreover, the impact of full duplex on other procedures such as search space configuration, resource allocation for DL and UL channels, ULJDL transmission and configuration procedures (e.g., multi-slot transmission), retuning, and reception of synchronization signal block (SSB) and reference signals needs to be considered.

The invention aims to provide apparatus and methods that at least partially address the above needs and/or issues.

In a first aspect the invention provides a method performed by an access network node for communicating with a user equipment, UE, the method comprising: transmitting, to the UE, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; transmitting, to the UE, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and receiving, from the user equipment, an uplink transmission in an uplink subband.

The broadcast transmission may comprise a synchronization signal block, SSB.

The UL subband configuration information may comprise an indication of a repeating set of time resources for an UL subband, wherein: a repetition period of the repeating set of time resources for the UL subband is the same as a repetition period of the repeating broadcast transmission; or the repetition period of the repeating broadcast transmission is an integer multiple of the repetition period of the repeating set of time resources for the UL subband.

The repetition period of the repeating set of time resources for the UL subband may be different from a duration of an instance of the at least one repeating pattern of time resources for UL communication and time resources for DL communication indicated by the first information.

The first information may indicate a plurality of repeating patterns of time resources for UL communication and time resources for DL communication; and the UL subband configuration information may indicate a plurality of sets of time resources for an UL subband, wherein each set of time resources is for use with a different respective repeating pattern of the plurality of repeating patterns of time resources for UL communication and time resources for DL communication.

In a second aspect the invention provides a method performed by a user equipment, UE, for communicating with an access network node, the method comprising: receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; receiving, from the access network node, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and transmitting, to the access network node, an uplink transmission in an uplink subband.

The broadcast transmission may comprise a synchronization signal block, SSB.

In a third aspect the invention provides a method performed by a user equipment, UE, for communicating with an access network node, the method comprising: receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication, and at least one set of time resources for an UL subband; receiving, from the access network node, a broadcast transmission; determining whether the at least one set of time resources for the UL subband at least partially overlaps in the time domain with the broadcast transmission; transmitting, to the access network node, an uplink transmission in an UL subband using the at least one set of time resources for the UL subband if it is determined that the at least one set of time resources for the UL subband does not at least partially overlap in the time domain with the broadcast transmission; and determining to not transmit, to the access network node, an uplink transmission in an UL subband using at least one time resource of the at least one set of time resources for the UL subband, if it is determined that at least one time resource of the at least one set of time resources for the UL subband overlaps in the time domain with the broadcast transmission.

The method may further comprise determining to discard an UL transmission or UL grant when at least one corresponding time resource for an UL subband at least partially overlaps in the time domain with the broadcast transmission.

The method may further comprise determining to not monitor at least one control resource set, CORESET, or downlink control information, DCI, when at least one corresponding time resource for an UL subband at least partially overlaps in the time domain with the broadcast transmission.

The method may comprise determining, when a portion of the at least one set of time resources for the UL subband overlaps in the time domain with the broadcast transmission and a portion of the at least one set of time resources for the UL subband does not overlap in the time domain with the broadcast transmission, to transmit an UL transmission in an UL subband using the portion of the at least one set of time resources for the UL subband that does not overlap in the time domain with the broadcast transmission, and not using, for UL transmission in an UL subband, the portion of the at least one set of time resources for the UL subband that overlaps in the time domain with the broadcast transmission.

The method may comprise determining, when at least one symbol for the UL subband overlaps in the time domain with the broadcast transmission and at least one symbol for the UL subband does not overlap in the time domain with the broadcast transmission, to transmit an UL transmission in an UL subband using the at least one symbol for the UL subband that does not overlap in the time domain with the broadcast transmission, and not using, for UL transmission in an UL subband, the at least one symbol for the UL subband that overlaps in the time domain with the broadcast transmission.

The broadcast transmission may be for radio link monitoring or link recovery.

In a fourth aspect the invention provides a method performed by a user equipment, UE, for communicating with an access network node, the method comprising: receiving, from the access network node, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; receiving, from the access network node, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and transmitting, to the access network node, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.

The method may further comprise transmitting, to the access network node, when the when the first information indicates that a time resource is to be used for an UL subband and the second information indicates that a time resource is to be used for DL communication, an UL subband transmission in an UL subband using the time resource.

The method may further comprise determining not to transmit, to the access network node, an UL subband transmission in an UL subband using a time resource when the first information indicates that the time resource is to be used for an UL subband and the second information indicates that the time resource is to be used for DL communication, but the second information does not include an indication that the time resource is to be used for an UL subband.

The first information may indicate a first pattern that is common to UEs in a cell of the access network node, and the second information may indicate a second pattern that is a dedicated pattern for the UE.

In a fifth aspect the invention provides a method performed by an access network node for communicating with a user equipment, UE, the method comprising: transmitting, to the user equipment, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; transmitting, to the user equipment, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and receiving, from the use equipment, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.

The method may further comprise receiving, from the user equipment, when the when the first information indicates that a time resource is to be used for an UL subband and the second information indicates that a time resource is to be used for DL communication, an UL subband transmission in an UL subband using the time resource.

In a sixth aspect the invention provides a method performed by an access network node for communicating with a user equipment, UE, the method comprising: transmitting, to the UE, time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.

The time gap configuration information indication may configure at least one of: the at least one UL communication time gap to be within the first time resource; or the at least one DL communication time gap to be within the third time resource.

The time gap configuration information indication may configure at least one of: the at least one UL communication time gap to be within the UL subband in the second time resource; or the at least one DL communication time gap to be within the DL subband in fourth time resource.

The time gap configuration information indication may configure at least one of: in a case where the first time resource is before the second time resource, the at least one UL communication time gap to be at the end of the first time resource; or in a case where the third time resource is before the fourth time resource, the at least one DL communication time gap to be at the end of the third time resource.

The time gap configuration information indication may configure at least one of: in a case where the first time resource is before the second time resource, the at least one UL communication time gap to be at the beginning of the second time resource; or in a case where the third time resource is before the fourth time resource, the at least one DL communication time gap to be at the beginning of the fourth time resource.

The time gap configuration information indication may configure at least one of: in a case where the first time resource is after the second time resource, the at least one UL communication time gap to be at the beginning of the first time resource; or in a case where the third time resource is after the fourth time resource, the at least one DL communication time gap to be at the beginning of the third time resource.

The time gap configuration information indication may configure at least one of: in a case where the first time resource is after the second time resource, the at least one UL communication time gap to be at the end of the second time resource; or in a case where the third time resource is after the fourth time resource, the at least one DL communication time gap to be at the end of the fourth time resource.

The time gap configuration information indication may configure at least one of: the at least one UL communication time gap to be within the UL subband in the second time resource regardless of whether the first time resource is before or after the second time resource; or the at least one DL communication time gap to be within the DL subband in fourth time resource regardless of whether the third time resource is before or after the fourth time resource.

The time gap configuration information may comprise a configuration of one or more flexible symbols.

In a seventh aspect the invention provides a method performed by user equipment, UE, for communicating with an access network node, the method comprising: obtaining time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.

Obtaining the time gap configuration information may comprise receiving the time gap configuration information from the access network node.

The time gap configuration information may be preconfigured at the UE.

In an eighth aspect the invention provides an access network node for communicating with a user equipment, UE, the access network node comprising: means for transmitting, to the UE, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; means for transmitting, to the UE, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and means for receiving, from the user equipment, an uplink transmission in an uplink subband.

In an ninth aspect the invention provides a user equipment, UE, for communicating with an access network node, the UE comprising: means for receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; means for receiving, from the access network node, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and means for transmitting, to the access network node, an uplink transmission in an uplink subband.

In a tenth aspect the invention provides a user equipment, UE, for communicating with an access network node, the UE comprising: means for receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication, and at least one set of time resources for an UL subband; means for receiving, from the access network node, a broadcast transmission; means for determining whether the at least one set of time resources for the UL subband at least partially overlaps in the time domain with the broadcast transmission; means for transmitting, to the access network node, an uplink transmission in an UL subband using the at least one set of time resources for the UL subband if it is determined that the at least one set of time resources for the UL subband does not at least partially overlap in the time domain with the broadcast transmission; and means for determining to not transmit, to the access network node, an uplink transmission in an UL subband using at least one time resource of the at least one set of time resources for the UL subband, if it is determined that at least one time resource of the at least one set of time resources for the UL subband overlaps in the time domain with the broadcast transmission.

In an eleventh aspect the invention provides a user equipment, UE, for communicating with an access network node, the UE comprising: means for receiving, from the access network node, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; means for receiving, from the access network node, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and means for transmitting, to the access network node, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.

In a twelfth aspect the invention provides an access network node for communicating with a user equipment, UE, the access network node comprising: means for transmitting, to the user equipment, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; means for transmitting, to the user equipment, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and means for receiving, from the use equipment, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.

In a thirteenth aspect the invention provides an access network node for communicating with a user equipment, UE, the access network node comprising: means for transmitting, to the UE, time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.

In a fourteenth aspect the invention provides a user equipment, UE, for communicating with an access network node, the UE comprising: means for obtaining time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings in which: Figures 1 to 4 are simplified time frequency diagrams illustrating a subband non-overlapping full duplex scheme and various exemplary implementations of such a scheme; Figure 5 schematically illustrates a mobile ('cellular' or 'wireless') telecommunication system; Figure 6 illustrates a typical frame structure that may be used in the telecommunication system of Figure 5; Figure 7 is a simplified sequence diagram illustrating different slot configuration procedures that can be employed in the telecommunication system of Figure 5; Figure 8 shows illustrative examples of slot configurations configured by the procedures of Figure 7, Figure 9 shows further illustrative examples of slot configurations configured by the procedures of Figure 7; Figure 10 is a simplified time frequency diagram showing illustrative examples of a non-interleaved CORESET design that may be used in the telecommunication system of Figure 5; Figure 11 is a simplified time frequency diagram showing an illustrative example of a full duplex configuration that may be used in the telecommunication system of Figure 5; Figure 12 is a simplified time frequency diagram showing an illustrative example of another full duplex configuration that may be used in the telecommunication system of Figure 5; Figure 13 is a simplified time frequency diagram showing an illustrative example of another full duplex configuration that may be used in the telecommunication system of Figure 5; Figure 14 shows an example in which an SSB is configured with a periodicity of 20 ms, and a TDD pattern is configured with a periodicity of 5 ms; Figure 15 shows an example in which a periodicity of an UL subband is the same as a periodicity of an SSB; Figure 16 shows an example in which a first SBFD pattern is used for TDD occasions that may overlap with the SSB, and a second SBFD pattern is used for TDD occasions that do not overlap with the SSB; Figure 17 shows an example in which UL subbands overlap with the SSB, but a conflict between the UL subbands and the SSB is nevertheless avoided; Figure 18 shows an example in which a common TDD configuration includes an indication of UL subband occasions, and a dedicated TDD configuration is also 30 provided; Figure 19 shows a modification of the example of figure 18 in which the dedicated TDD configuration comprises an indication of UL subband occasions; Figure 20 shows an example of when retuning may occur at the interfaces of different UL bandwidths; Figure 21 shows an example in which a guard period is provided from the start of the first UL-only symbol when a transition occurs from an UL-subband slot/symbol to an UL-only slot/symbol, and from the start of the first UL-subband symbol when a transition occurs from an UL-only slot/symbol to an UL-subband slot/symbol Figure 22 shows an example in which the guard period is provided at the end of the UL-subband slots/symbols when a transition occurs from an UL-subband slot/symbol to an UL-only slot/symbol, and at the end of the UL-only slots/symbols when a transition occurs from an UL-only slot/symbol to an UL-subband slot symbol; Figure 23 shows an example in which the guard period is provided at the end of the UL-subband slots/symbols when a transition occurs from an UL-subband slot/symbol to an UL-only slot/symbol, and at from the start of the first UL-subband symbol when a transition occurs from an UL-only slot/symbol to an UL-subband slot/symbol; Figure 24 is a schematic block diagram illustrating the main components of a UE for the telecommunication system of Figure 5; and Figure 25 is a schematic block diagram illustrating the main components of a base station for the telecommunication system of Figure 5.

Overview An exemplary telecommunication system will now be described in general terms, by way of example only, with reference to Figs. 5 to 12.

Fig. 5 schematically illustrates a mobile ('cellular' or 'wireless') telecommunication system 'I to which embodiments of the present invention are applicable.

In the network 1 user equipment (UEs) 3-1, 3-2, 3-3 (e.g. mobile telephones and/or other mobile 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 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. 5 for illustration purposes, the system, when implemented, will typically include other base stations 5 and UEs 3.

Each base station 5 controls the associated cell(s) 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) 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 Ni reference point (analogous to the Si reference point in LTE). It will be appreciated, that Ni communications are routed transparently via the base station 5.

The UPF(s) 11 are connected to an external data network (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 nonNAS 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 stations 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 and for transmission of a number of physical signals. The DL physical channels correspond to resource elements (REs) carrying information originated from a higher layer, and the DL physical signals 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, 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 UE 3 may receive a Synchronization Signal Block (SSB), and the UE 3 may assume that reception occasions of a PBCH, primary synchronization signal (PSS) and secondary synchronization signal (SSS) are in consecutive symbols and form a SS/PBCH block. The base station 5 may transmit a number of synchronization signal (SS) blocks corresponding to different DL beams. The total number of SS blocks may be confined, for example, within a 5 ms duration as an SS burst. The periodicity of the SSB transmissions may be indicated to the UE using any suitable signalling (e.g. per serving cell using ssb-periodicityServingCell).

The periodicity value for the SSB may be, for example, greater than or equal to 20 ms. For initial cell selection, the UE 3 may be configured to assume that an SS burst occurs with a periodicity of 2 frames. The UE 3 may also be provided with an indication of which SSBs within a 5 ms duration are transmitted (e.g. using ssb-PositionsInBurst).

The DL physical signals may include, 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 a UL control/data signal, and/or sounding reference signals (SRS) used for UL channel measurement.

Referring to Fig. 6, which illustrates the typical frame structure that may be used in the telecommunication system 1, the base station Sand UEs 3 of the telecommunication system 1 communicate with one another using resources that are organised, in the time domain, into frames 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 Orthogonal frequency-division multiplexing (OFDM) symbols of equal length.

As seen in Fig. 6, 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, p, where p=0 represents 15 kHz (corresponding to the LTE SCS). Currently, the SCS for other values of p can, in effect, be derived from p=0 by scaling up in powers of 2 (i.e. SCS = 15 x 2P kHz). The relationship between the parameter, p, and SCS (Af) is as shown in Table 1: a Af = 2/' *15 [kHz] Number of slots Slot length (ms) per subframe 0 15 1 1 1 30 2 0.5 2 60 4 0.25 3 120 8 0.125 4 240 16 0.0625 Table 1 -5G Numerology General Slot Configuration Referring to Figs. 7 and 8 the base station 5 configures the slot usage within each cell 9 operated on a TDD carrier appropriately.

As seen in Fig. 7, which is a simplified sequence diagram illustrating different slot configuration procedures (3710, 3714, 3718) that can be employed in the communication system 1, the base station 5 is capable of employing a number of different procedures for configuring slot usage in each cell 9 operated on the TDD carrier.

As seen in procedure 3710, for example, the base station 5 of the communication system 1 is configured for providing a respective common (or 'cell specific') slot configuration, for each cell 9 operated on a TDD carrier. This common slot configuration can be provided using system information (as illustrated at S710a) to all UEs 3 within the cell (for example in a tdd-UL-DL-ConfigurationCommon information element (1E) of system information block type 1 (SIB1)). This common slot configuration can also be provided using dedicated (e.g., radio resource control (RRC)) signalling (as illustrated at 3710b) to specific UEs 3 within the cell (for example in a tdd-UL-DL-ConfigurationCommon IE of an RRC message such as an RRC reconfiguration message or the like). On receipt of the common slot configuration a UE 3 can thus set a common slot format configuration per slot over a number of slots (as seen at 3712).

As seen in Fig. 8, which shows illustrative examples of slot configurations configured by the procedures of Fig. 7, the slots may be configured as downlink only slots, as uplink only slots, or as unallocated or 'flexible' slots (that may be downlink or uplink).

The common slot configuration is defined by a number of parameters provided by the base station 5 as part of the common UL/DL configuration. These parameters include: a slot configuration period (e.g., configured by a dl-UL-TransmissionPeriodicity 1E); a number of slots with only downlink symbols (e.g., configured by a nrofDownlinkSlots 1E); a number of downlink symbols (e.g., configured by a nrofDownlinkSymbols 1E); a number of slots with only uplink symbols (e.g., configured by a nrofUplinkSlots 1E); and a number of uplink symbols (e.g., configured by a nrofUplinkSymbols 1E). As seen in Fig. 8, these effectively configure a repeating pattern of slot types (repeating at the slot configuration period), which in this example comprises DL only slots and symbols, followed by flexible slots and symbols, followed by UL only slots and symbols. The repeating pattern starts with a DL group comprising the defined number of DL only slots followed by the defined number of DL only symbols in the next slot. The repeating pattern ends with a UL group comprising the defined number of UL only slots preceded by the defined number of UL only symbols in the preceding slot. The flexible symbols and slots are those between the DL group of DL only slots and symbols and the UL group of UL only slots and symbols.

Fig. 9 shows a further example in which two TDD patterns are configured (for example using the procedures of Fig. 7). The first pattern (Pattern 1) has a first period P1 and is followed by a second patten having a second period P2. The combined periodicity of the TDD configuration is the sum of the first period and the second period, P1+P2. In other words, for each cycle, for a first duration of P1 the first TDD pattern is used, and for the following duration of P2 the second TDD pattern is used (resulting in a total periodicity P3, equal to P1+P2, for the entire sequence). It will be appreciated that the first periodicity P1 need not necessarily be equal to the second periodicity P2.

As seen in procedure S714, the base station 5 of the communication system 1 is also configured for providing, if required, a dedicated (or 'UE specific') slot configuration for a specific UE 3. This dedicated slot configuration can be provided using dedicated (e.g., radio resource control (RRC)) signalling (as illustrated at S715) to a specific UE 3 within the cell (for example in a tdd-UL-DL-ConfigurationDedicated IE of an RRC message such as an RRC reconfiguration message or the like). Various methods of handing the case in which the UE 3 is provided with the dedicated slot configuration in addition to the common slot configuration will be described in more detail later.

The dedicated configuration, if provided, includes individual slot specific configuration(s) (e.g., using a slotSpecificConfigurationsToAddModList 1E) in which each slot configuration contains information (e.g., a slotindex 1E) identifying a specific slot within the slot configuration period defined by the common slot configuration, and information defining a symbol structure (e.g., a symbols 1E). The information defining the symbol structure provides the direction (downlink or uplink) for the symbols within the specific slot that is being configured. The information defining the symbols structure may, for example: indicate that all symbols in the specific slot are used for the downlink (e.g., by setting the symbols IE to callDownlink1); indicate that all symbols in the specific slot are used for the uplink (e.g., by setting the symbols IE to allUplinki); or explicitly indicate how many symbols at the beginning and the end of the specific slot are allocated to downlink and uplink, respectively (e.g., a nrofDownlinkSymbols IE may indicate the number of consecutive downlink symbols in the beginning of the slot identified by the slot index, and a nrofUplinkSymbols IE may indicate the number of consecutive uplink symbols at the end of the slot identified by the slot index).

A UE 3 can thus set a dedicated slot format configuration per slot over a number of slots (as seen at S716).

A UE 3 thus treats symbols in a slot indicated as downlink by the common slot configuration, or the dedicated slot configuration, to be available for receptions. Similarly a UE 3 treats symbols in a slot indicated as uplink by the common slot configuration, or the dedicated slot configuration to be available for transmissions.

Even after the slot configurations in a cell-specific and UE-specific manner described above, the slot configuration may have some more flexible slots/symbols left unallocated. By making use of layer 1 signalling, the remaining Of any) flexible symbols can dynamically be reconfigured.

As seen in procedure S718, for example, the base station 5 of the communication system 1 is also configured for providing one or more dynamic slot configurations to a group of one or more UEs 3 by means of a physical downlink control channel (PDCCH). The dynamic slot configuration(s) can be provided using downlink control information (DCI) using an appropriate DCI format (e.g., DCI format 2_0), as illustrated at S719, to a specific group of one or more UEs 3 within the cell 9.

Indexes atone or more slot format indicators (SFIs) are provided within the payload of the DCI for the group of one or more UEs 3. To allow the DCI to be addressed to and decoded by the UE(s) 3 of the group, cyclic redundancy check (CRC) bits of the DCI are scrambled with an associated radio network temporary identifier (RNTI), for example a slot format indicator RNTI (SFI-RNTI') or the like. The UE(s) in the group are allocated with the same RNTI. Each UE 3 of the group is configured to extract its own SFI-index based on the position of the SFI-index within the DCI payload (this position may, for example, be configured by UE specific RRC signalling). The RRC configuration may, for example, be by means of an RRC message carrying a PDCCH serving cell configuration I E having a slot format indicator (SFI) IE that, for a specific serving cell (identified by a serving cell ID (e.g., by a servingCellId IE)): provides an SFI-RNTI; defines one or more slot format combinations (e.g., by a slotFormatCombinations 1E); and specifies the starting position (bit), in the DCI, of the SFI index that is applicable for the configured UE (e.g., by a positionl nDCI 1E).

Each SFI-index provided by the DCI acts as a pointer to a combination of slot formats (where each slot format corresponds to a respective combination of downlink, uplink, and/or flexible symbols) for defining a slot format for each slot in a number of slots starting from a slot where the UE detects the dynamic slot configuration DCI format.

Thus, for any slot indicated to a UE 3 as flexible by both a common slot configuration and a dedicated slot configuration, the DCI can be used to dynamically configure downlink, uplink, and/or flexible symbols within that slot (as seen in the example of Fig. 8) A UE 3 can thus set a dynamic slot format configuration per slot over a number of slots (as seen at S720).

Bandwidth Parts (BWPs) In the communication system 1 the cell bandwidth can be divided into multiple bandwidth parts (BVVPs) that each start at a respective common resource block (RB) and respectively comprises of a set of contiguous RBs with a given numerology (sub-carrier spacing, 'SOS', and cyclic prefix, 'CP') on a given carrier. It will be appreciated that conventionally the number of downlink symbols, uplink symbols, and flexible symbols in each slot of the slot configuration (e.g., common or dedicated) would be common to each configured BWP.

The UEs 3 and base station 5 of the communication system 1 are thus configured for operation using BWPs. For each serving cell of a UE 3, the base station Scan configure at least one downlink (DL) BWP (e.g. an initial DL BWP). The base station 5 may configure the UE 3 with up to a maximum (typically four) DL BWPs with only a single DL BWP being active at a given time. The UE 3 is not expected to receive PDSCH, PDCCH, or CSI-RS (except for radio resource management (RRM)) outside an active bandwidth part. Where the serving cell is configured with an uplink (UL), the base station 5 can configure at least one UL BWP (e.g. an initial UL BWP). The base station 5 may configure the UE 3 with up to a maximum (typically four) UL BWPs with only one UL BWP being active at a given time. The UE 3 does not transmit PUSCH or PUCCH outside an active bandwidth part. For an active cell, the UE 3 does not transmit SRS outside an active bandwidth part. It will be appreciated that the slot format indicator (e.g., an SF1-index field value) in the dynamic slot configuration DCI format may indicate to a UE 3 a slot format for each slot in a number of slots for each DL BWP or each UL BWP.

A BWP identifier or index (BWP-ID) is used to refer to BWPs (in UL and DL independently). Various radio resource control (RRC) configuration procedures can thus use the BWP-ID to associate themselves with a particular BWP.

VVhile for paired spectrum (FDD), DL BWPs and UL BWPs are configured separately, for unpaired spectrum (TDD), a DL BWP is effectively linked to (paired with) a UL BWP, with the paired DL BWP and UL BWP sharing the same BWP-ID and centre frequency (but possibly different bandwidths).

Specifically, the base station 5 is able to configure an initial DL BWP (e.g. by means of an initialDownlinkBWP 1E) via system information (e.g. system information block 1, '31131') and/or via dedicated (e.g. RRC) signalling (e.g. an RRC reconfiguration, RRC resume, or RRC setup message). For example, the common parameters for the initial DL BWP may be provided via system information whereas UE specific parameters may be provided via dedicated signalling (e.g. in a ServingCellConfig IE within an RRC message that contains a dedicated, UE-specific, BWP configuration). The dedicated signalling may also contain some cell-specific information which may be useful for specific scenarios (e.g. handover).

The base station 5 is able to configure an initial UL BWP (e.g. by means of an initialUplinkBWP 1E) via system information (e.g. system information block 1, (SIBI) and/or via dedicated (e.g. RRC) signalling (e.g. an RRC reconfiguration, RRC resume, or RRC setup message). For example, the common parameters for the initial UL BWP(s) may be provided via system information whereas UE specific parameters may be provided via dedicated signalling (e.g. in a ServingCellConfig IF within an RRC message that contains a dedicated, UE-specific, BWP configuration). This provides configuration information either for a so-called special cell (SpCell) -which is a primary cell (PCell) of a master cell group (MCG) or secondary cell group (SCG) -or a secondary cell (SCell).

The initial DL and UL BWPs are used at least for initial access before an RRC connection is established. The initial BWP is known as BWP#0 as it has a BWP identifier (or index') of zero. Prior to receiving system information defining a UE's initial DL BWP, the DL BWP for each UE 3 has a frequency range and numerology corresponding to a control resource set (CORESET) -e.g. CORESET #0 -defined by a master information block (MIS) (or possibly dedicated RRC signalling). The CORESET is used to carry downlink control information (DCI) transmitted via a PDCCH for scheduling system information blocks.

After receiving the system information (e.g. SI B1) a UE 3 uses the BWP configuration defined by that system information to configure the initial DL BWP and initial UL BWP. The configured initial UL BWP is then used to initiate a random-access procedure for setting up an RRC connection. The base station 5 configures the frequency domain location and bandwidth of the initial DL BWP in the system information so that the initial DL BWP contains the entire CORESET #0 in the frequency domain.

For each DL BWP in a set of DL BWPs for a primary cell (PCell), a UE 3 can be configured with CORESETs for every type of common search space (CSS) set (sometimes referred to as a cell-specific search space (CSS)) and for a UE-specific search space (USS) set. For each UL BWP in a set of UL BWPs of a PCell, or of a PUCCH-secondary cell, the UE 3 is configured resource sets for PUCCH transmissions.

The UE 3 is configured for switching its active BWP between its configured BWPs when required. For example, switching at the UE 3 may be initiated by receipt of a scheduling DCI, by expiry of an inactivity timer (e.g., a BWPInactivityTimer), and/or by initiation of a random-access procedure.

PDCCH Configuration Each UE 3 is configured to monitor a set of PDCCH candidates in one or more CORESETs on the currently active DL BWP according to corresponding search space sets. This monitoring involves decoding each PDCCH candidate according to corresponding monitored DCI formats.

Each set of PDCCH candidates for a UE 3 to monitor is defined in terms of PDCCH search space sets, where a search space set may be a CSS set or a USS set as described above. For example, a given UE 3 may monitor PDCCH candidates in one or more of the following search spaces sets: * a PDCCH CSS set related to transmission of a PDCCH for a system information (SI) message (e.g., SIB1 carrying remaining minimum system information ('RMS1')). Such a CSS may be referred to as a Type 0 PDCCH CSS and may be configured by an appropriate search space configuration IE for a DCI format with a CRC scrambled by a system information RNTI (SI-RNTI) on a PCell (e.g., in a so-called pdcch-ConfigSIB1' IE provided in the MIB, or in a so-called csearchSpaceSIBI or csearchSpaceZero' in a PDCCH-ConfigCommon' IE of an appropriate RRC message); * a PDCCH CSS set related to transmission of a PDCCH for other system information (e.g., carried by other SIBs). Such a CSS may be referred to as a Type OA PDCCH CSS set and may be configured by an appropriate search space configuration IE for a DCI format with CRC scrambled by a SI-RNTI on a PCell (e.g., in a so-called 'searchSpaceOtherSysteml nformation' IE provided in a PDCCH-ConfigCommon' IF of an appropriate RRC message); * a PDCCH CSS set related to a random-access procedure. Such a CSS may be referred to as a Type 1 PDCCH CSS set and may be configured by an appropriate search space configuration IE for a DCI format with CRC scrambled by an appropriate RNTI on a PCell (e.g., random access RNTI (RARNTI), a random-access response message (RAR / MsgB) RNTI (MsgB-RNTI), or a temporary cell RNTI (TC-RNTI). The search space configuration IE may, for example, be a so-called cra-SearchSpace' IE provided in a 'POOCH-ConfigCommon' IE of an appropriate RRC message; * a PDCCH CSS set related to paging. Such a CSS may be referred to as a Type 2 PDCCH CSS set and may be configured by an appropriate search space configuration IE for a DCI format with CRC scrambled by an appropriate RNTI on a PCell (e.g., paging RNTI (P-RNTI)). The search space configuration IE may, for example, be a so-called cpagingSearchSpace' IF provided in a PDCCH-ConfigCommon' IE of appropriate RRC message; * a PDCCH CSS set related to other procedures (such as scheduling, power control etc.). Such a CSS may be referred to as a Type 3 PDCCH CSS set and may be configured by an appropriate search space configuration IE for a DCI format with CRC scrambled by an appropriate RNTI on an SCell or PCell. The RNTI may, for example, be an interruption RNTI (INT-RNTI), an SFI-RNTI, a PUSCH power control RNTI (TPC-PUSCH-RNTI), a PUCCH power control RNTI (TPC-PUCCH-RNTI), an SRS trigger and power control RNTI (TPC-SRSRNTI), a cancellation indication RNTI (CI-RNTI), a cell RNTI (C-RNTI), a modulation and coding scheme cell RNTI (MCS-C-RNTI), one or more configured scheduling CS-RNTI(s), or a power saving RNTI (PS-RNTI). The search space configuration IF may, for example, be a so-called 'SearchSpace' IE provided in a PDCCH-Config' IE of appropriate RRC message; * a USS set for DCI formats with CRC scrambled by an appropriate RNTI. The RNTI may, for example, be a C-RNTI, an MCS-C-RNTI, a semi-persistent (SP) channel state information (CSI) RNTI (SP-CSI-RNTI), and or one or more CSRNTI(s). The search space configuration IE may, for example, be a so-called 'SearchSpace' IF provided in a PDCCH-Config' IF of appropriate RRC message.

For each search space set, the UE 3 is provided with information for configuring: an association between the search space set and a CORESET; a PDCCH monitoring periodicity and a PDCCH monitoring offset; a PDCCH monitoring pattern within a slot; an indication that search space set is either a CSS set or a USS as appropriate; and/or one or more DCI format(s) to monitor.

It will be appreciated that CSS sets are expected to be used by both older 'legacy' UEs that are not configured for SBFD communication, and more modern UEs that are configured to support SBFD communication, at least for monitoring broadcast channels.

The way in which CORESETs may be configured will now be described in more detail with reference to Fig. 10, which is a simplified time frequency diagram showing illustrative examples of a non-interleaved CORESET design.

Each CORESET may be described in terms of resource groupings at different levels of granularity as follows: * A resource element (RE), which is the smallest unit within the 5G NR resource grid and consists of one subcarrier in the frequency domain and one symbol in time domain; * A resource element group (REG), which comprises a single RB in the frequency domain (where each RB comprises 12 subcarriers/REs in the frequency domain) and one symbol in the time domain; * A REG bundle, which comprises multiple REGs. The bundle size is (in number of REGs) is variable (typically specified by a parameter indicated in RRC signalling using an appropriate IE (e.g. teg-bundle-sizen * A control channel element (CCE), which comprises a number of REGs (six in current 5G systems but hypothetically variable) in units of one or more REG bundles (depending on REG bundle size); and * An aggregation level, which indicates the number CCEs allocated for a PDCCH.

Currently NR supports both distributed and localised resource allocation for a DCI in a CORESET. Distributed resource allocation for a DCI may be achieved by configuring an interleaved CCE-to-REG mapping for each CORESET whereas localised resource allocation (as illustrated in Fig. 10) for a DCI may be achieved by configuring a non-interleaved CCE-to-REG mapping for each CORESET.

For non-interleaved CCE-to-REG mapping, all CCEs for a DCI with a given aggregation level L are mapped to consecutive REG bundles of the CORESET. For interleaved CCE-to-REG mapping, REG bundles constituting the CCEs for a PDCCH are distributed in the frequency domain in units of REG bundles. To support this, block interleaving is used where the interleaving spans across all REGs present in the CORESET.

A given DCI having a specific aggregation level, L, may therefore comprise L continuously numbered CCEs in which the CCEs are mapped on to a number of REGs (which may be grouped in non-contiguous REG bundles in the case of interleaving) in a given CORESET.

As explained above, a serving cell can have up to four BWPs. Each of these BWPs can currently have up to three CORESETs. The base station 5 provides the UE 3 with information for configuring the CORESET(s).

This configuration information typically includes, for example, information for identifying a number of consecutive symbols (e.g., 1, 2, or 3) representing a duration of the CORESET. The configuration information also typically includes information identifying a set of frequency domain resources (e.g., a set of RBs) -for example, in the form of an appropriate frequency domain resources IE (e.g., a frequencyDomainResources 1E) defining the resources. The frequency domain resources IE may, for example be in the form of a bitmap, or the like, in which each bit corresponds a group of frequency resources (e.g., a group of six RBs) in which the grouping starts from an initial physical frequency resource (e.g., physical RB (PRB 0) that is fully contained in the BWP within which the corresponding CORESET is configured. It will be appreciated that the term PRB generally refers to RBs that are indexed in frequency order in the frequency domain. This contrasts with virtual RBs (VRBs) which, when arranged in numerical order, may (but does not have to) correspond to physical frequency resources (subcarriers, PRBs, groups thereof, or the like) that are not arranged in frequency order.

The configuration information also typically comprises CCE-to-REG mapping information for use in identifying the resources forming each CCE and hence each PDCCH candidate. The CCE-to-REG mapping information typically includes information defining the REG bundle size (e.g., 'mg-bundle-size') and, where interleaving is used, information identifying an interleaver size and potentially a shift index (which may be a physical cell identity).

The configuration information defining a CORESET is typically provided using RRC signalling. However, the CORESET having index 0 (CORESET #0) is a special CORESET that is configured using a four-bit information element in the MIB.

An example of an interleaved CCE-to-Reg bundle mapping is illustrated in Table 2 below. The mapping shown is for a 48 PRB CORESET in which the PRBs are indexed consecutively (from 0 to 47) in the frequency domain. The REG bundle size is 6 REGs (PRBs), the duration of the CORESET is 1 symbol in the time domain, the interleaver size is 2, and the shift index is 160.

CCE(j) REG Bundle Indices of REGs Index (PRBs) in bundle 0 0 0, 1, 2, 3, 4, 5 1 4 24,25,26,27,28,29 2 1 6" 9, 10, 11 3 5 30, 31, 32, 33, 34, 35 4 2 12, 13, 14, 15, 16, 17 6 36, 37, 38, 39, 40, 41 6 3 18, 19, 20, 21, 22, 23 7 7 42, 43, 44, 45, 46, 47

Table 2

It can be seen that in this example, every even numbered CCE is mapped to the next REG bundle in increasing frequency from the bottom to the middle of the available 48 RB CORESET frequency range. Every odd numbered CCE is mapped to the next REG bundle in increasing frequency from the middle to the top of the available 48 RB CORESET frequency range.

It can be seen, therefore, that for interleaved CCE to REG mapping, frequency resources for each PDCCH candidate will be distributed (essentially randomly) over the CORESET bandwidth. This has the potential to present a challenge for SBFD implementations in which UL communications from one UE 3 could interfere with the communication of DCI in a PDCCH for another UE 3.

PDSCH/PUSCH Resource Allocation Resource allocation for communication on the PDSCH or the PUSCH, in the communication system 1, can be based on either of two types of resource allocation schemes.

In the first type of resource allocation (referred to as Type-0), the allocation is indicated by means of resource block assignment information that includes a bitmap indicating one or more resource block groups (RBGs) that have been allocated to the scheduled UE. Each RBG is a set of consecutive virtual resource blocks (VRBs). The size of the RBG On number of resource blocks) is defined by a higher layer RBG size parameter (e.g., 'rbg-Size') and the size of the BVVF' to which the allocation relates. The RBG size parameter essentially indicates one of a plurality of possible RBG size configurations and the actual RBG size for each RBG size configuration is dependent on the BWP bandwidth. For example, for a 36 RB bandwidth the RBG size for a first RBG size configuration may be two RBs, whereas the RBG size for a second RBG size configuration may be four RBs. Contrastingly, for a 144 RB bandwidth the RBG size for the first RBG size configuration may be eight RBs, whereas the RBG size for the second RBG size configuration is sixteen RBs. Each RBG of a given BWP is therefore addressable via the bitmap without needing to increase the bitmap size for larger BWPs.

In the second type of resource allocation (referred to as Type-1), the allocation is indicated by means of resource block assignment information that indicates a set of contiguously allocated non-interleaved, or interleaved, VRBs within the active BWP.

For non-interleaved VRBs, a VRB having index n is mapped to a corresponding PRB having the same index n. For interleaved VRBs, the VRB-to-PRB mapping involves bundling the RBs (both virtual and physical) into RB bundles (RBBs) in increasing order of RB indices and RBB indices. Each virtual RBB (VRBB) is mapped to a physical RBB (PRBB) based on block interleaving such that a given VRBB index may not be the same as the corresponding PRBB index. Thus, if a set of contiguous VRBBs are assigned to a UE 3 the corresponding PRBBs may not be contiguous in frequency, and may, instead, be distributed at different (separated) positions in the bandwidth of the corresponding BWP.

Dynamic switching between the different types of resource allocation is possible by means of an indication included within DCI having an appropriate DCI format (e.g. DCI format 0_1 (for PUSCH), DCI format 1_1 (for PDSCH), 'compact' DCI format 0_2 (for PUSCH), or 'compact' DCI format 1_2 (for PDSCH)).

It will be appreciated that for multi-slot PUSCH/PDSCH, frequency domain resource allocations will remain the same for all slots. Nevertheless, frequency resources for adjacent slots may still be different where frequency hopping is used (as described in more detail later).

It can be seen, therefore, that for the second type (Type-1) resource allocation (with interleaving) frequency resources for PDSCH/PUSCH may be distributed (essentially randomly) over the BWP bandwidth. This has the potential to present a challenge for SBFD implementations in which UL/DL communications of one UE 3 could interfere with the PDSCH/PUSCH communication of another UE 3.

Frequency Hopping For communication on the PUSCH, in the communication system 1, one of a plurality of different frequency hopping modes can be configured.

A first hopping mode, for example, comprises intra-slot frequency hopping in which frequency hopping can occur within a slot. Intra-slot frequency hopping is applicable both to single slot and multi-slot PUSCH transmission.

A first hopping mode, for example, comprises inter-slot frequency hopping in which frequency hopping can occur from slot-to-slot. Inter-slot frequency hopping is applicable to multi-slot PUSCH transmission.

For intra-slot hopping, the starting RB in each hop is given by: RB,art RBstart =(RBstart RBoffset) mod ntrir where 1=0 and 1=1 are the first hop and the second hop respectively, and RBstart is the starting RB within the UL BWP, as calculated from the resource block assignment 1=0 i = 1 information (e.g., of a Type-1 resource allocation), RBoffset is the frequency offset in RBs between the two frequency hops, and NAZ is the size of the BWP in RBs. For inter-slot hopping, the starting RB during slot nsu, is given by: RBst", n isf mod 2 = 0 = (RBstar, + RBoffset) mod Nsigep mod 2 = 1 where rtsu is the current slot number within a radio frame, where a multi-slot PUSCH transmission can take place, RBstart is the starting RB within the UL BVVP, as calculated from the resource block assignment information (e.g., of a Type-1 resource allocation), RBoffset is the frequency offset in RBs between the two frequency hops, and NOgp is the size of the BVVP in RBs.

For the second type of resource allocation (e.g., Type-1), the UE 3 performs PUSCH frequency hopping if the frequency hopping field in a corresponding detected DCI format (or in a random-access response UL grant) is set to 1. The frequency offsets may be configured by a higher layer parameter (e.g., a frequencyHoppingOffsetLists parameter), where one of the higher layer configured offsets may be indicated in the UL grant.

Provision of Full Duplex The UEs 3 and base station 5 of the communication system 1 are mutually configured for providing full duplex (FD) communication on a TDD carrier. Specifically, the UEs 3 and base station 5 of the communication system 1 are configured to facilitate subband non-overlapping FD (SBFD) communication.

For example, as seen in Fig. 11, which is a simplified time frequency diagram showing an illustrative example of a full duplex configuration that may be used in the communication system 1, the different UE specific slot configurations allow a slot within the cell bandwidth to effectively be configured as an FD slot by configuring that slot for one UE as an uplink slot, while the same slot is configured as a downlink slot for another UE (or vice versa). Thus, UL communication from one UE 3 in the cell bandwidth may occur in parallel with DL communication to another UE 3. It will be appreciated that while not specifically illustrated the parallel ULJDL communication may be configured at a symbol level as well as at the slot level.

It will be appreciated that the base station 5 is configured to schedule frequency resources of any slot configured as an FD slot, to ensure that the frequency resources scheduled for UL communication by one UE 3 are part of a different subband than the frequency resources scheduled for DL communication to another UE 3. Accordingly, subband non-overlapping FD communication can thus take place at the base station while half-duplex communication takes place at the UEs 3.

The base station 5 is thus able to configure one or more of the slots (and/or symbols) of the TDD carrier as FD slots (and/or symbols) or more specifically, in a case where, subband non-overlapping full duplex (SBFD) is used for full duplex operation, SBFD slots (and/or symbols). For convenience, slots/symbols which contain both UL and DL subbands, from the base station's perspective, will be referred to generally as SBFD' slots/symbols, or slots/symbols with a configured UL subband/DL subband. Other slots/symbols, which only contains communication in a single transmission direction (UL or DL) will generally be referred to as legacy (UL or DL) slots/symbols or non-SBFD (UL or DL) slots/symbols.

It will be appreciated that, from a UE perspective, an SBFD slot or symbol may appear to be a legacy UL, DL, or flexible symbol because the UE 3 is operating using half duplex on the TDD carrier. Nevertheless, a UE 3 may be informed of the FD/SBFD slots/symbols, either implicitly or explicitly, to allow the UE 3 to assist with interference avoidance / alleviation. For example, if the UE 3 can identify the FD/SBFD slots/symbols then the UE 3 may: contribute to the implementation of an appropriate frequency gap between the frequency resources used by that UE 3 (e.g., for UL or DL) and the frequency resources used by another UE 3 (e.g., for DL or UL); avoid, reconfigure, and/or apply updated resources, in respect of certain transmissions/receptions (e.g., for semi-static transmission such as SPS).

For example, the base station 5 may explicitly indicate which slots/symbols are configured as FD/SBFD type slots/symbols, for example, dynamically using DCI with an appropriate DCI format and/or using a Medium Access Control (MAC) Control Element (CE). The base station 5 may, alternatively or additionally explicitly indicate which slots/symbols are configured as FD/SBFD type slots/symbols via system information or dedicated (RRC) signalling (for example, by means of frame structure signalling similar to that used for the cell specific and/or dedicated TDD ULJDL slot configuration). A UE 3 may implicitly determine whether a slot/symbol is configured as an FD/SBFD type slots/symbol based on other information received from the network (base station 5). For example, the UE may assume that an SBFD slot occurs when the base station 5 indicates that an UL transmission is to take place during a DL configured slot or that a DL transmission is to take place during a UL configured slot.

It will be appreciated that there are different variations which exist for implementation of SBFD, and the communication system 1 may be configured to provide support for any suitable SBFD schemes. Such schemes may include, for example, inter-BWP full duplex and/or intra-BWP full duplex.

Referring to Fig. 12, for example, which is a simplified time frequency diagram showing an illustrative example of an inter-BWP type of full duplex configuration, inter-BWP full duplex involves parallel UL and DL transmission in different BWPs in which a particular slot of one BWP may be configured as an uplink slot while the corresponding slot (i.e., having the same timing) in another BWP may be configured as a downlink slot (or vice versa). Thus, UL from one UE 3 in one BWP may occur in parallel with DL communication to another UE 3 in another BWP.

Referring to Fig. 13, on the other hand, which is a simplified time frequency diagram showing an illustrative example of an intra-BWP type of full duplex configuration, intra-BWP full duplex involves parallel UL and DL transmission in the same BWP. In the example illustrated in Fig. 13, an UL subband is effectively inserted within a slot/symbol configured as a (legacy) DL or flexible slot/symbol of a BWP. Specifically, each time resource of the BWP is configured as a DL, a UL, or a flexible slot/symbol (for example using a TDD configuration technique as described with reference to Figs. 4 and 5). An UL subband (e.g., a set of contiguous UL frequency resources) is then configured within the BWP for at least a subset of one or more of the DL or flexible slots/symbols to effectively form a slot/symbol that consists of a UL subband and one or two DL subbands. The configuration of the UL subband(s) may be achieved in any suitable way, for example by semi-static configuration and/or dynamic configuration. A guard band (frequency gap) may be configured, between the UL subband and each DL subband, where no transmission is performed, thereby helping to avoid interference. The base station 5 can then schedule UL transmission in the UL subband and DL transmission in DL subband(s) as necessary. It will be appreciated that while Fig. 13 shows a UL subband being inserted in a downlink or flexible slot/symbol, a similar mechanism may also be used to insert a DL subband within an UL or flexible slot/symbol to achieve SBFD.

It will be appreciated that while several procedures are described that may be implemented in the communication system 1 to provide a corresponding benefit, not all the procedures need to be implemented to achieve a beneficial result. Specifically, any one of the following procedures may be implemented independently of the others. Nevertheless, many of the procedures are not mutually exclusive and can be implemented together where it is technically appropriate to do so.

UL Subband and SSB / Type-0 PDDCH / Broadcast Channels The present inventors have realised that improved methods of dealing with a situation in which both SSB and SBFD are provided for a UE 3 are needed. Reception of the SSW-Type-0 PDCCH/broadcast channels may be prioritized by the UE, and therefore the configuration of the UL subbands must be carefully considered in order to achieve sufficient utilization of SBFD whilst also ensuring that there is no conflict with the SSBs.

Configuration of UL Subbands Fig. 14 shows an example in which an SSB is configured with a periodicity of 20 ms, and a TDD pattern is configured with a periodicity of 5 ms. The resources allocated for the UL subband and the configuration of the SSB/Type-0 PDCCH are controlled by the network, and the network performs control such that the UL subband and the SSW-Type-0 PDCCH do not overlap in the time domain. The periodicity of the SSB may be, for example, 20 ms or 40 ms, with an SSB window (duration) of 5 ms. In contrast, the TDD periodicity may be up to 10 ms (e.g. 5 ms). In the example shown in Fig. 14 the TDD has a duration of 5 ms, of which 4 ms is used for DL and 1 ms is used for UL. In this example the SSB occupies the first 3 ms of the TDD pattern, and therefore the UL subband is not configured in the first 3 ms of the TDD pattern in order to avoid conflict with the SSB; if the UL subband overlapped with the SSB then the UE 3 would not be able to use the UL subband if the UE 3 is configured for half duplex operation and reception of the SSB or broadcast signal has a higher priority. Since the period of the TDD pattern (5 ms) is shorter than the period of the SSB (20 ms), during many of the TDD occasions no corresponding SSB is transmitted. However, since only one TDD pattern is used for all of the TDD occasions, the UL subband is not configured in the first 3 ms of the TDD pattern even when there is no corresponding SSB to avoid conflict with. Therefore, there is a problem that SBFD is under-utilized in the periods in which there is no SSB transmission. In the example of Fig. 14, only 25% of the symbols available for SBFD are utilized in TDD occasions for which there is no SSB. It will be appreciated that whilst Fig. 14 is described with reference to SSB, this problem also occurs with any other Type-0 PDCCH or broadcast transmission to be prioritised for reception by the UE 3.

An improved method of scheduling the UL subbands will now be described with reference to Fig. 15, in which the periodicity of the UL subband is advantageously different from the TDD periodicity. In this example, the periodicity of the UL subband is the same as the periodicity of the SSB. Beneficially, as shown in Fig. 15, this enables the SBFD to be configured such that the UL subbands do not overlap with the SSB, but makes improve use of the available resources in TDD occasions in which there is no SSB that overlaps in the time domain. Whilst in the example of Fig. 14 only 25% of the symbols available for SBFD are utilized in TDD occasions for which there is no SSB, in the improved configuration of Fig. 15 all of the available symbols are utilized for SBFD in TDD occasions for which there is no SSB, improving the efficiency of the communications between the UE 3 and the base station 5. The configuration for the UL subbands may be indicated to the UE 3 using any suitable signalling or transmissions. For example, the network may indicate the slots/symbols in which the UL subband occurs using RRC signalling.

Fig. 16 shows a further example in which two SBFD patterns are used. In this example, a first SBFD pattern (SBFD Pattern 1) is used for TDD occasions that may overlap with the SSB, and a second SBFD pattern (SBFD Pattern 2) is used for TDD occasions that do not overlap with the SSB. The second SBFD pattern contains a larger number of UL subband symbols than the first SBFD pattern, increasing the utilization of SBFD in the TDD occasions that do not overlap with the SSB, whilst the configuration of the first SBFD pattern ensures that there is no conflict between the UL subband occurrences and the SSB. The first and second SBFD patterns need not necessarily have the same duration; this may be particularly useful when more than one TDD pattern is used (e.g. in the example illustrated in Fig. 9). The two SBFD patterns may be associated with (e.g. mapped) to respective TDD patterns (for example, first and second TDD patterns indicated in tdd-UL-DL-ConfigurafionCommon) such that each SBFD pattern has the same duration as associated TDD pattern.

It will be appreciated that Figs. 14 to 16 illustrate the relationship between the UL subbands, TDD pattern and SSB in the time domain, and that any suitable configuration for the UL subbands in the frequency domain may be used (e.g. one or more of the configurations illustrated in Figs. 1 to 4).

UE Procedure A method in which UL subbands overlap with the SSB, but a conflict between the UL subbands and the SSB is nevertheless avoided, will now be described with reference to Fig. 17.

As shown in the figure, in this example the UL subbands are configured to span the duration of the DL transmissions, achieving full utilization of SBFD in the TDD occasions in which there is no overlap with SSB. In this example, in the TDD occasions that overlap with SSB, the UE 3 is configured to determine that there is overlap between an UL subband and the SSB, and is configured to determine that the overlapping UL subband is not to be used (e.g. the overlapping UL subband is discarded by the UE 3). The UE 3 may determine that an UL subband is overlapping with the SSB (or any other suitable broadcast channel or reference signal) if a subset of the symbols of the UL subband are the same as those used for the SSB, or if the UL subband starting symbol is less than a threshold time duration after the end of the SSB transmission. The threshold time duration may be preconfigured at the UE 3, or alternatively may be determined, for example, based on a UE timing advance value.

The threshold time duration may be determined at the UE 3, or may alternatively be indicated to the UE 3 by the network (via the base station 5).

When the UE 3 determines that an UL subband overlaps with the SSB, the UE 3 may determine to discard an UL transmission or UL grant associated with the UL subband. 20 The UE 3 may determine to not monitor CORESET/DCI associated with the UL subband.

The UE 3 may be configured to discard (e.g. not use for uplink transmissions) only the portion of the UL subband (e.g. symbol(s) of the UL subband) that overlaps with the SSB in the time domain, and to use the non-overlapping portions (e.g. the symbols that do not overlap with the SSB) of that UL subband for UL transmissions.

The UE 3 may be configured to only discard an UL subband that overlaps with the SSB if the UL subband overlaps with a particular subset of SSBs. The subset of SSBs may be the SSB(s) currently selected or camped on by the UE 3, or may be, for example, SSBs that are transmitted in proximity of the UE's 3 currently selected or camped SSB.

The UE 3 may be configured to only discard an UL subband that overlaps with a reference signal if the reference signal is to be used for radio link monitoring or link recovery.

The UE 3 may be configured to discard or utilise an UL subband that overlaps with SSB based on a determination that the UE 3 should receive the SSB (or other suitable broadcast channel or reference signal). For example, if the UL subband overlaps with RMSI, but the UE 3 is not required to receive RMSI, then the UE 3 may determine to not discard the UL subband, and may use the UL subband for uplink transmissions.

Advantageously, in the example shown in Fig. 17, SBFD is efficiently utilized whilst conflict between the UL subbands and the SSB is beneficially avoided as a result of the detection, by the UE 3, of overlaps between the UL subbands and the SSB.

Common and Dedicated TDD Configurations Examples in which both a common TDD configuration and a dedicated TDD configuration are provided to a UE 3 will now be described. Examples of how common TDD configurations (e.g. tdd-UL-DL-ConfigurationCommon 1E) and dedicated TDD configurations (e.g. tdd-UL-DL-ConfigurationDedicated 1E) may be provided have been described above with reference to Fig. 7.

A common TDD configuration provided to the UE 3 may provide UL subband time occasions that can overlap with flexible and DL slots/symbols configured by the common TDD configuration. However, the present inventors have realised that improved methods are needed for handing the case in which both a common TDD configuration and a dedicated TDD configuration are provided to the UE 3, to achieve a more efficient configuration in the time domain for the UL subbands.

In the present examples, for slots/symbols configured in a dedicated TDD configuration as UL slots/symbols, if those UL slots/symbols contain UL subband configured by the common TDD configuration, then the UE 3 is configured to discard (e.g. treat as invalid) the UL subband for those slots/symbols.

Fig. 18 shows an example in which the common TDD configuration includes an indication of UL subband occasions, and a dedicated TDD configuration is also provided. The resulting UL subband configuration in the time domain is also shown. In this example, the UE 3 is configured to treat the UL subband occasions indicated in the common TDD configuration as valid UL subband occasions (that the UE 3 may use for subband uplink transmissions) when the corresponding slots/symbols of the dedicated TDD configuration are indicated as DL or flexible slots/symbols. The UE 3 is configured to discard the UL subband when the corresponding slots/symbols in the dedicated TDD configuration are indicated as UL slots/symbols.

Fig. 19 shows a modification of the example of Fig. 18 in which the dedicated TDD configuration comprises an indication of UL subband occasions. The base station 5 provides an indication, to the UE 3, of a configuration for UL subband time occasions for slots/symbols configured as DL or flexible slots/symbols. In the example shown in Fig. 19, for each TDD period the dedicated TDD configuration includes an indication of time occasions for corresponding UL subband occasions. As shown in the figure, when the dedicated TDD configuration indicates that slots/symbols are for use as DL slots/symbols, and also indicates UL subband for those slots/symbols, the UE 3 is configured to use the indicated UL subband (or treat the indicated UL subband as valid). When the dedicated TDD configuration indicates that slots/symbols are for use as DL slot/symbols but does not indicate that those slots/symbols are for UL subband, then the UE 3 does not use UL subband for those slots/symbols. The UE 3 may be configured to discard (e.g. not use, or treat as invalid) UL subband time occasions indicated in the common TDD configuration for slots/symbols indicated as DL or flexible slots/symbols without UL subband in the dedicated TDD configuration.

Alternatively, the UE 3 may be configured not to discard the UL subband time occasions indicated in the common TDD configuration when no UL subband time occasion configuration is provided in the dedicated TDD configuration.

Advantageously, in the examples shown in Figs. 18 and 19, the UL subband occasions can be efficiently and unambiguously configured, and the utilization of the available slots/symbols for SBFD is high, even when both a common TDD configuration and a dedicated TDD configuration are provided.

Transitions between UL Subbands and an UL-only slot When a transition between a slot/symbol containing UL subband and an UL-only slot/symbol occurs, the base station 5 may need to reconfigure a filter (e.g. an analog filter) to account for the change in the UL bandwidth. Fig. 20 shows an example of when such retuning may occur at the interfaces of different UL bandwidths. This reconfiguration can result in interruption of UL reception, which has a negative impact on, for example, physical channel procedures. This is because it is possible that when an UL-only slot/symbol and an UL subband slot/symbol are adjacent, the base station 5 may not receive an UL transmission during the consequential retuning for the new bandwidth. A corresponding issue may occur at the UE 3 when the UE 3 uses similar filters for transmission and/or reception. The inventors have realised that improved methods for handling the transition from an UL-only slot/symbol to an UL subband slot/symbol (and for transitions from an UL subband slot/symbol to an UL-only slot/symbol) are needed, to improve the efficiency and reliability of communications in the system.

In one example, the base station 5 configures a time gap between UL subband slot/symbols and UL-only slot symbols in which no UL transmissions are scheduled.

The time gap may also be referred to as a guard period. Advantageously, the base station 5 can perform reconfiguration of the filter during the guard period, reducing the risk that the UE 3 transmits an uplink transmission to the base station 5 whilst the base station is performing the reconfiguration. The base station 5 may provide an indication of the time gap to the UE 3 in any suitable transmission or signalling (e.g. RRC signalling). Alternatively, a time delay (guard period) may be preconfigured at the UE 3 for use at transitions from an UL-only slot/symbol to an UL subband slot/symbol (and from an UL subband slot/symbol to an UL-only slot/symbol). In a further alternative, the time gap may be configured in the form of one or more flexible symbols configured by the base station at transitions from an UL-only slot/symbol to an UL subband slot/symbol (and/or from an UL subband slot/symbol to an UL-only slot/symbol). The time gap may be a fraction of a symbol, one or multiple symbols, or a slot.

Restriction, prevention, or reduction of UL transmissions in the guard period may be achieved in any suitable manner, by any suitable signalling between the UE 3 and the base station 5. The base station 5 may provide an UL configuration such that an UL-subband is not configured/present within the guard period. For example, if flexible symbols are used for the guard period, then the base station 5 may configure no UL subband occasions within a number of N flexible symbols that are arranged before the start (or after the end) of an UL slot/symbol at which a change in the UL bandwidth occurs. Alternatively, the base station 5 may simply not schedule any UL transmissions within the time gap. In a further alternative, the UE 3 may perform rate-matching/puncturing in the UL transmissions, or discard UL resources, in order to avoid UL transmission during the guard periods. If discarding is performed, then the UE 3 may discard only a part of the UL transmission that overlaps the guard period if the UL transmission partially overlaps the guard period. Alternatively, the UE 3 may discard the complete UL transmission if the UL transmission partially overlaps the guard period.

Fig. 21 shows an example in which the guard period is provided from the start of the first UL-only symbol when a transition occurs from an UL-subband slot/symbol to an UL-only slot/symbol, and from the start of the first UL-subband symbol when a transition occurs from an UL-only slot/symbol to an UL-subband slot/symbol.

Fig. 22 shows an example in which the guard period is provided at the end of the ULsubband slots/symbols when a transition occurs from an UL-subband slot/symbol to an UL-only slot/symbol, and at the end of the UL-only slots/symbols when a transition occurs from an UL-only slot/symbol to an UL-subband slot symbol.

Fig. 23 shows a particularly advantageous example in which the guard period is provided at the end of the UL-subband slots/symbols when a transition occurs from an UL-subband slot/symbol to an UL-only slot/symbol, and at from the start of the first ULsubband symbol when a transition occurs from an UL-only slot/symbol to an ULsubband slot/symbol. This configuration is particularly beneficial since the UL radio resource wastage is reduced by providing the guard periods in the relatively low bandwidth UL-subband slots/symbols, rather than the in the relatively high bandwidth UL-only slots/symbols.

Whilst guard bands in the frequency domain are shown in the examples of Figs. 20 to 23, it will be appreciated that these need not necessarily be provided.

It will be appreciated that whilst the guard period has been described with reference to UL transmissions, the same principles and methods also apply to DL transmissions. For example, the guard period can be implemented in the same manner when a transition occurs between an UL-subband slot and a DL-only slot.

User Equipment Fig. 24 is a schematic block diagram illustrating the main components of a UE 3 as shown in Fig. 5.

As shown, the UE 3 has a transceiver circuit 31 that is operable to transmit signals to and to receive signals from a base station 5 via one or more antenna 33 (e.g., comprising one or more antenna elements). The UE 3 has a controller 37 to control the operation of the UE 3. The controller 37 is associated with a memory 39 and is coupled to the transceiver circuit 31. 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 35, 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 39 and/or may be downloaded via the telecommunications network or from a removable data storage device (RMD), for example.

The controller 37 is configured to control overall operation of the UE 3 by, in this example, program instructions or software instructions stored within memory 39. As shown, these software instructions include, among other things, an operating system 41, and a communications control module 43.

The communications control module 43 is operable to control the communication between the UE 3 and its serving base station(s) 5 (and other communication devices connected to the base station 5, such as further UEs and/or core network nodes). The communications control module 43 is configured for the overall handling 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 43 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 43 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 bandwidth part(s) 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 43 may be configured to control communications in accordance with any of the methods described above (for example, to perform UL subband transmissions).

Base Station Fig. 25 is a schematic block diagram illustrating the main components of the base station 5 for the communication system 1 shown in Fig. 5. As shown, the base station has a transceiver circuit 51 for transmitting signals to and for receiving signals from the communication devices (such as UEs 3) via one or more antenna 53 (e.g. a single or multi-panel antenna array / massive antenna), and a core network interface 55 (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 57 to control the operation of the base station 5. The controller 57 is associated with a memory 59. Software may be pre-installed in the memory 59 and/or may be downloaded via the communications network 1 or from a removable data storage device (RMD), for example. The controller 57 is configured to control the overall operation of the base station 5 by, in this example, program instructions or software instructions stored within memory 59.

As shown, these software instructions include, among other things, an operating system 61 and a communications control module 63.

The communications control module 63 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 63 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 63 is also configured for the overall handling 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 63 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 43 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 ULJDL 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 bandwidth part(s) for the UE 3; for providing related configuration signalling to the UE 3; and the like. The communications control module 43 may be configured to control communications in accordance with any of the methods described above (for example, to control transmission of the dedicated TDD configuration or the common TDD configuration).

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

It will be appreciated, for example, 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 invention, 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 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 (10) 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 loT devices, loT 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 (loT)", 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, loT devices may comprise automated equipment that follow software instructions stored in an internal memory. loT devices may operate without requiring human supervision or interaction. loT devices might also remain stationary and/or inactive for a long period of time. loT devices may be implemented as a part of a (generally) stationary apparatus. loT 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 loT 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 loT 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 loT 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.

Service Area MTC applications Security Surveillance systems Backup for landline Control of physical access (e.g. to buildings) Car/driver security Tracking & Tracing Fleet Management Order Management Pay as you drive Asset Tracking Navigation Traffic information Road tolling Road traffic optimisation/steering Payment Point of sales Vending machines Gaming machines Health Monitoring vital signs Supporting the aged or handicapped Web Access Telemedicine points Remote diagnostics Remote Maintenance/Control Sensors Lighting Pumps Valves Elevator control Vending machine control Vehicle diagnostics Metering Power Gas Water Heating Grid control Industrial metering Digital photo frame Consumer Devices Digital camera eBook 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 Mulficast 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 exemplary embodiments described in the present document.

Needless to say, these technical ideas and 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.

Claims

Claims 1. A method performed by an access network node for communicating with a user equipment, UE, the method comprising: transmitting, to the UE, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; transmitting, to the UE, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and receiving, from the user equipment, an uplink transmission in an uplink subband.
2. The method according to claim 1, wherein the broadcast transmission comprises a synchronization signal block, SSB.
3. The method according to any preceding claim, wherein the UL subband configuration information comprises an indication of a repeating set of time resources for an UL subband, wherein: a repetition period of the repeating set of time resources for the UL subband is the same as a repetition period of the repeating broadcast transmission; or the repetition period of the repeating broadcast transmission is an integer multiple of the repetition period of the repeating set of time resources for the UL subband.
4. The method according to claim 3, wherein the repetition period of the repeating set of time resources for the UL subband is different from a duration of an instance of the at least one repeating pattern of time resources for UL communication and time resources for DL communication indicated by the first information.
5. The method according to any preceding claim, wherein the first information indicates a plurality of repeating patterns of time resources for UL communication and time resources for DL communication; and wherein the UL subband configuration information indicates a plurality of sets of time resources for an UL subband, wherein each set of time resources is for use with a different respective repeating pattern of the plurality of repeating patterns of time resources for UL communication and time resources for DL communication.
6. A method performed by a user equipment, UE, for communicating with an access network node, the method comprising: receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; receiving, from the access network node, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and transmitting, to the access network node, an uplink transmission in an uplink subband.
7. The method according to claim 6, wherein the broadcast transmission comprises a synchronization signal block, SSB.
8. The method according to claim 6 or 7, wherein the UL subband configuration information comprises an indication of a repeating set of time resources for an UL subband, wherein: a repetition period of the repeating set of time resources for the UL subband is the same as a repetition period of the repeating broadcast transmission; or the repetition period of the repeating broadcast transmission is an integer multiple of the repetition period of the repeating set of time resources for the UL subband.
9. The method according to claim 8, wherein the repetition period of the repeating set of time resources for the UL subband is different from a duration of an instance of the at least one repeating pattern of time resources for UL communication and time resources for DL communication indicated by the first information.
10. The method according to any one of claims 6 to 9, wherein the first information indicates a plurality of repeating patterns of time resources for UL communication and time resources for DL communication; and wherein the UL subband configuration information indicates a plurality of sets of time resources for an UL subband, wherein each set of time resources is for use with a different respective repeating pattern of the plurality of repeating patterns of time resources for UL communication and time resources for DL communication.
11. A method performed by a user equipment, UE, for communicating with an access network node, the method comprising: receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication, and at least one set of time resources for an UL subband; receiving, from the access network node, a broadcast transmission; determining whether the at least one set of time resources for the UL subband at least partially overlaps in the time domain with the broadcast transmission; transmitting, to the access network node, an uplink transmission in an UL subband using the at least one set of time resources for the UL subband if it is determined that the at least one set of time resources for the UL subband does not at least partially overlap in the time domain with the broadcast transmission; and determining to not transmit, to the access network node, an uplink transmission in an UL subband using at least one time resource of the at least one set of time resources for the UL subband, if it is determined that at least one time resource of the at least one set of time resources for the UL subband overlaps in the time domain with the broadcast transmission.
12. The method according to claim 11, the method further comprising determining to discard an UL transmission or UL grant when at least one corresponding time resource for an UL subband at least partially overlaps in the time domain with the broadcast transmission.
13. The method according to claim 11 or 12, the method further comprising determining to not monitor at least one control resource set, CORESET, or downlink control information, DCI, when at least one corresponding time resource for an UL subband at least partially overlaps in the time domain with the broadcast transmission.
14. The method according to any one of claims 11 to 13, wherein the method comprises determining, when a portion of the at least one set of time resources for the UL subband overlaps in the time domain with the broadcast transmission and a portion of the at least one set of time resources for the UL subband does not overlap in the time domain with the broadcast transmission, to transmit an UL transmission in an UL subband using the portion of the at least one set of time resources for the UL subband that does not overlap in the time domain with the broadcast transmission, and not using, for UL transmission in an UL subband, the portion of the at least one set of time resources for the UL subband that overlaps in the time domain with the broadcast transmission.
15. The method according to claim 14, wherein the method comprises determining, when at least one symbol for the UL subband overlaps in the time domain with the broadcast transmission and at least one symbol for the UL subband does not overlap in the time domain with the broadcast transmission, to transmit an UL transmission in an UL subband using the at least one symbol for the UL subband that does not overlap in the time domain with the broadcast transmission, and not using, for UL transmission in an UL subband, the at least one symbol for the UL subband that overlaps in the time domain with the broadcast transmission.
16. The method according to any one of claims 11 to 15, wherein the broadcast transmission is for radio link monitoring or link recovery.
17. A method performed by a user equipment, UE, for communicating with an access network node, the method comprising: receiving, from the access network node, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; receiving, from the access network node, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and transmitting, to the access network node, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.
18. The method according to claim 17, wherein the method further comprises transmitting, to the access network node, when the when the first information indicates that a time resource is to be used for an UL subband and the second information indicates that a time resource is to be used for DL communication, an UL subband transmission in an UL subband using the time resource.
19. The method according to claim 17, wherein the method further comprises determining not to transmit, to the access network node, an UL subband transmission in an UL subband using a time resource when the first information indicates that the time resource is to be used for an UL subband and the second information indicates that the time resource is to be used for DL communication, but the second information does not include an indication that the time resource is to be used for an UL subband.
20. The method according to any one of claims 17 to 19, wherein the first information indicates a first pattern that is common to UEs in a cell of the access network node, and the second information indicates a second pattern that is a dedicated pattern for the UE.
21. A method performed by an access network node for communicating with a user equipment, UE, the method comprising: transmitting, to the user equipment, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; transmitting, to the user equipment, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and receiving, from the use equipment, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.
22. The method according to claim 21, wherein the method further comprises receiving, from the user equipment, when the when the first information indicates that a time resource is to be used for an UL subband and the second information indicates that a time resource is to be used for DL communication, an UL subband transmission in an UL subband using the time resource.
23. The method according to claim 21 to 22, wherein the first information indicates a first pattern that is common to UEs in a cell of the access network node, and the second information indicates a second pattern that is a dedicated pattern for the UE.
24. A method performed by an access network node for communicating with a user equipment, UE, the method comprising: transmitting, to the UE, time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.
25. The method according to claim 24, wherein the time gap configuration information indication configures at least one of: the at least one UL communication time gap to be within the first time resource; or the at least one DL communication time gap to be within the third time resource.
26. The method according to claim 24, wherein the time gap configuration information indication configures at least one of: the at least one UL communication time gap to be within the UL subband in the second time resource; or the at least one DL communication time gap to be within the DL subband in fourth time resource.
27. The method according to claim 24, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is before the second time resource, the at least one UL communication time gap to be at the end of the first time resource; or in a case where the third time resource is before the fourth time resource, the at least one DL communication time gap to be at the end of the third time resource.
28. The method according to claim 24, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is before the second time resource, the at least one UL communication time gap to be at the beginning of the second time resource; or in a case where the third time resource is before the fourth time resource, the at least one DL communication time gap to be at the beginning of the fourth time resource.
29. The method according to claim 24, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is after the second time resource, the at least one UL communication time gap to be at the beginning of the first time resource; or in a case where the third time resource is after the fourth time resource, the at least one DL communication time gap to be at the beginning of the third time resource.
30. The method according to claim 24, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is after the second time resource, the at least one UL communication time gap to be at the end of the second time resource; or in a case where the third time resource is after the fourth time resource, the at least one DL communication time gap to be at the end of the fourth time resource.
31. The method according to claim 24, wherein the time gap configuration information indication configures at least one of: the at least one UL communication time gap to be within the UL subband in the second time resource regardless of whether the first time resource is before or after the second time resource; or the at least one DL communication time gap to be within the DL subband in fourth time resource regardless of whether the third time resource is before or after the fourth time resource.
32. The method according to claim 24, wherein the time gap configuration information comprises a configuration of one or more flexible symbols.
33. A method performed by user equipment, UE, for communicating with an access network node, the method comprising: obtaining time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.
34. The method according to claim 33, wherein the time gap configuration information indication configures at least one of: the at least one UL communication time gap to be within the first time resource: or the at least one DL communication time gap to be within the third time resource.
35. The method according to claim 33, wherein the time gap configuration information indication configures at least one of: the at least one UL communication time gap to be within the UL subband in the second time resource; or the at least one DL communication time gap to be within the DL subband in fourth time resource.
36. The method according to claim 33, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is before the second time resource, the at least one UL communication time gap to be at the end of the first time resource; or in a case where the third time resource is before the fourth time resource, the at least one DL communication time gap to be at the end of the third time resource.
37. The method according to claim 33, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is before the second time resource, the at least one UL communication time gap to be at the beginning of the second time resource; or in a case where the third time resource is before the fourth time resource, the at least one DL communication time gap to be at the beginning of the fourth time resource.
38. The method according to claim 33, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is after the second time resource, the at least one UL communication time gap to be at the beginning of the first time resource; or in a case where the third time resource is after the fourth time resource, the at least one DL communication time gap to be at the beginning of the third time resource.
39. The method according to claim 33, wherein the time gap configuration information indication configures at least one of: in a case where the first time resource is after the second time resource, the at least one UL communication time gap to be at the end of the second time resource; or in a case where the third time resource is after the fourth time resource, the at least one DL communication time gap to be at the end of the fourth time resource.
40. The method according to claim 33, wherein the time gap configuration information indication configures at least one of: the at least one UL communication time gap to be within the UL subband in the second time resource regardless of whether the first time resource is before or after the second time resource; or the at least one DL communication time gap to be within the DL subband in fourth time resource regardless of whether the third time resource is before or after the fourth time resource.
41. The method according to claim 33, wherein the time gap configuration information comprises a configuration of one or more flexible symbols.
42. The method according to any one of claims 33 to 41, wherein obtaining the time gap configuration information comprises receiving the time gap configuration information from the access network node.
43. The method according to any one of claims 33 to 41, wherein the time gap configuration information is preconfigured at the UE.
44. An access network node for communicating with a user equipment, UE, the access network node comprising: means for transmitting, to the UE, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; means for transmitting, to the UE, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and means for receiving, from the user equipment, an uplink transmission in an uplink subband.
45. A user equipment, UE, for communicating with an access network node, the UE comprising: means for receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication; means for receiving, from the access network node, UL subband configuration information comprising an indication of a first set of at least one time resource for an UL subband when an instance of the at least one repeating pattern does not overlap in the time domain with a repeating broadcast transmission, and a second set of at least one time resource for an UL subband when an instance of the at least one repeating pattern at least partially overlaps with the broadcast transmission in the time domain; and means for transmitting, to the access network node, an uplink transmission in an uplink subband.
46. A user equipment, UE, for communicating with an access network node, the UE comprising: means for receiving, from the access network node, first information indicating at least one repeating pattern of time resources for uplink, UL, communication and time resources for downlink, DL, communication, and at least one set of time resources for an UL subband, means for receiving, from the access network node, a broadcast transmission; means for determining whether the at least one set of time resources for the UL subband at least partially overlaps in the time domain with the broadcast transmission; means for transmitting, to the access network node, an uplink transmission in an UL subband using the at least one set of time resources for the UL subband if it is determined that the at least one set of time resources for the UL subband does not at least partially overlap in the time domain with the broadcast transmission; and means for determining to not transmit, to the access network node, an uplink transmission in an UL subband using at least one time resource of the at least one set of time resources for the UL subband, if it is determined that at least one time resource of the at least one set of time resources for the UL subband overlaps in the time domain with the broadcast transmission.
47. A user equipment, UE, for communicating with an access network node, the UE comprising: means for receiving, from the access network node, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; means for receiving, from the access network node, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and means for transmitting, to the access network node, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.
48. An access network node for communicating with a user equipment, UE, the access network node comprising: means for transmitting, to the user equipment, first information indicating a first pattern of at least one of time resources for uplink, UL, communication, time resources for downlink, DL, communication, and time resources for an UL subband; means for transmitting, to the user equipment, second information indicating a second pattern of at least one of time resources for UL communication and time resources for DL communication, and time resources for an UL subband; and means for receiving, from the use equipment, when the first information indicates that a time resource is to be used for an UL subband and DL communication, an uplink transmission in an UL subband using the time resource.
49. An access network node for communicating with a user equipment, UE, the access network node comprising: means for transmitting, to the UE, time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.
50. A user equipment, UE, for communicating with an access network node, the UE comprising: means for obtaining time gap configuration information for configuring at least one of: at least one uplink, UL, communication time gap adjacent an interface between a first time resource that is configured for UL communication, and a UL subband in a second time resource that is configured for DL communication; or at least one downlink, DL, communication time gap adjacent an interface between a third time resource that is configured for DL communication, and a DL subband in a fourth time resource that is configured for UL communication.