WO2022148573A1

WO2022148573A1 - Methods, communications devices, and infrastructure equipment

Info

Publication number: WO2022148573A1
Application number: PCT/EP2021/083418
Authority: WO
Inventors: Shin Horng Wong; Naoki Kusashima; Yassin Aden Awad; Martin Warwick Beale
Original assignee: Sony Group Corporation; Sony Europe B.V.
Priority date: 2021-01-05
Filing date: 2021-11-29
Publication date: 2022-07-14

Abstract

A method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface is provided. The method comprises transmitting a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, and determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data. In accordance with the determination, the method comprises either transmitting the second portion of the data in the overlap region, or refraining from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Description

METHODS. COMMUNICATIONS DEVICES. AND INFRASTRUCTURE EQUIPMENT

BACKGROUND Field of Disclosure

The present disclosure relates to communications devices, infrastructure equipment and methods for the transmission of data by a communications device in a wireless communications network.

The present invention claims the Paris Convention priority from European patent application number EP21150311.5, the contents of which are hereby incorporated by reference.

Description of Related Art

The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present invention.

Latest generation mobile telecommunication systems, such as those based on the 3GPP defined UMTS and Long Term Evolution (LTE) architecture, are able to support a wider range of services than simple voice and messaging services offered by previous generations of mobile telecommunication systems. For example, with the improved radio interface and enhanced data rates provided by LTE systems, a user is able to enjoy high data rate applications such as mobile video streaming and mobile video conferencing that would previously only have been available via a fixed line data connection. The demand to deploy such networks is therefore strong and the coverage area of these networks, i.e. geographic locations where access to the networks is possible, is expected to continue to increase rapidly.

Future wireless communications networks will be expected to routinely and efficiently support communications with an ever-increasing range of devices associated with a wider range of data traffic profiles and types than existing systems are optimised to support. For example, it is expected future wireless communications networks will be expected to efficiently support communications with devices including reduced complexity devices, machine type communication (MTC) devices, high resolution video displays, virtual reality headsets and so on. Some of these different types of devices may be deployed in very large numbers, for example low complexity devices for supporting the “The Internet of Things”, and may typically be associated with the transmissions of relatively small amounts of data with relatively high latency tolerance. Other types of device, for example supporting high-definition video streaming, may be associated with transmissions of relatively large amounts of data with relatively low latency tolerance. Other types of device, for example used for autonomous vehicle communications and for other critical applications, may be characterised by data that should be transmitted through the network with low latency and high reliability. A single device type might also be associated with different traffic profiles / characteristics depending on the application(s) it is running. For example, different consideration may apply for efficiently supporting data exchange with a smartphone when it is running a video streaming application (high downlink data) as compared to when it is running an Internet browsing application (sporadic uplink and downlink data) or being used for voice communications by an emergency responder in an emergency scenario (data subject to stringent reliability and latency requirements).

In view of this there is expected to be a desire for future wireless communications networks, for example those which may be referred to as 5G or new radio (NR) systems / new radio access technology (RAT) systems, as well as future iterations / releases of existing systems, to efficiently support connectivity for a wide range of devices associated with different applications and different characteristic data traffic profiles and requirements.

One example of a new service is referred to as Ultra Reliable Low Latency Communications (URLLC) services which, as its name suggests, requires that a data unit or packet be communicated with a high reliability and with a low communications delay. Another example of a new service is Enhanced Mobile Broadband (eMBB) services, which are characterised by a high capacity with a requirement to support up to 20 Gb/s. URLLC and eMBB type services therefore represent challenging examples for both LTE type communications systems and 5G/NR communications systems.

The increasing use of different types of network infrastructure equipment and terminal devices associated with different traffic profiles give rise to new challenges for efficiently handling communications in wireless communications systems that need to be addressed.

SUMMARY OF THE DISCLOSURE

The present disclosure can help address or mitigate at least some of the issues discussed above.

Embodiments of the present technique can provide a method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface. The method comprises transmitting a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, and determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data. In accordance with the determination, the method comprises either transmitting the second portion of the data in the overlap region, or refraining from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Embodiments of the present technique, which, in addition to methods of operating communications devices, relate to methods of operating infrastructure equipment, communications devices and infrastructure equipment, and circuitry for communications devices and infrastructure equipment, allow for more efficient use of radio resources by a communications device.

Respective aspects and features of the present disclosure are defined in the appended claims.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the present technology. The described embodiments, together with further advantages, will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein like reference numerals designate identical or corresponding parts throughout the several views, and wherein:

Figure 1 schematically represents some aspects of an LTE-type wireless telecommunication system which may be configured to operate in accordance with certain embodiments of the present disclosure;

Figure 2 schematically represents some aspects of a new radio access technology (RAT) wireless telecommunications system which may be configured to operate in accordance with certain embodiments of the present disclosure;

Figure 3 is a schematic block diagram of an example infrastructure equipment and communications device which may be configured to operate in accordance with certain embodiments of the present disclosure;

Figure 4 illustrates an example of a New Radio Unlicensed (NR-U) Channel Access on a grid of radio communications resources;

Figure 5 illustrates an example of Type 1 and Type 2 Dynamic Channel Access (DCA) on an uplink and downlink grid of radio communications resources;

Figure 6 illustrates examples of Type 2 DCA on a grid of radio communications resources;

Figure 7 shows an example of a Fixed Frame Period (FFP) for Channel Occupancy Time (COT) initiation in Semi-static Channel Access (SCA);

Figure 8 shows an example of synchronised gNB FFPs in a controlled environment;

Figure 9 illustrates how separate FFPs for a gNB and for a User Equipment (UE) may be offset;

Figure 10 shows an example of a gNB initiating a COT while still under a UE-initiated COT;

Figure 11 illustrates how a gNB’s transmission may collide with a UE’s transmission after the gNB has initiated a COT;

Figure 12 illustrates how a UE’s COT duration may be reduced if the UE is no longer allowed to transmit after the idle period of a gNB’s FFP which is offset with the UE’s FFP;

Figure 13 shows a part schematic, part message flow diagram representation of a wireless communications network comprising a communications device and an infrastructure equipment in accordance with embodiments of the present technique;

Figure 14 shows an example of an explicit indication received within an overlap region between a UE- initiated COT and a gNB-initiated COT after the idle period of a gNB’s FFP of whether or not the UE can transmit during the overlap region in accordance with embodiments of the present technique;

Figure 15 shows an example of how the absence of a gNB transmission during an overlap region between a UE-initiated COT and a gNB-initiated COT may implicitly indicate that the UE is allowed to transmit in the overlap region in accordance with embodiments of the present technique;

Figure 16 shows an example of an explicit indication received before the idle period of a gNB’s FFP which indicates whether or not the UE can transmit during an overlap region between a UE-initiated COT and a gNB-initiated COT in accordance with embodiments of the present technique;

Figure 17 shows an example of how the presence of a gNB transmission received before the idle period of the gNB’s FFP can indicate whether or not the UE can transmit during an overlap region between a UE- initiated COT and a gNB-initiated COT in accordance with embodiments of the present technique;

Figure 18 shows an example of an uplink (UL) grant which indicates whether or not a UE can transmit during an overlap region between a UE-initiated COT and a gNB-initiated COT in accordance with embodiments of the present technique;

Figure 19 shows an example of how Downlink Feedback Information, DFI, can be used to indicate that a UE should not transmit during an overlap region between a UE-initiated COT and a gNB-initiated COT in accordance with embodiments of the present technique; Figure 20 shows an example of how a UE may determine whether or not to transmit during an overlap region between a UE-initiated COT and a gNB-initiated COT based on the length of the overlap region in accordance with embodiments of the present technique;

Figure 21 shows a first example of how a UE may determine whether or not to transmit during an overlap region between a UE-initiated COT and a gNB-initiated COT based on whether a response is received from the gNB to a request transmitted by the UE within a predetermined response period, where the predetermined response period starts and ends before the idle period of the gNB’s FFP, in accordance with embodiments of the present technique;

Figure 22 shows a second example of how a UE may determine whether or not to transmit during an overlap region between a UE-initiated COT and a gNB-initiated COT based on whether a response is received from the gNB to a request transmitted by the UE within a predetermined response period, where the predetermined response period starts before the idle period of the gNB’s FFP and ends between the end of the idle period of the gNB’s FFP and the UE-initiated COT, in accordance with embodiments of the present technique;

Figure 23 shows a third example of how a UE may determine whether or not to transmit during an overlap region between a UE-initiated COT and a gNB-initiated COT based on whether a response is received from the gNB to a request transmitted by the UE within a predetermined response period, where the predetermined response period starts after the idle period of the gNB’s FFP and ends before the end of the UE-initiated COT, in accordance with embodiments of the present technique; and Figure 24 shows a flow diagram illustrating a process of communications in a communications system in accordance with embodiments of the present technique.

DETAILED DESCRIPTION OF THE EMBODIMENTS Long Term Evolution Advanced Radio Access Technology (4G)

Figure 1 provides a schematic diagram illustrating some basic functionality of a mobile telecommunications network / system 6 operating generally in accordance with LTE principles, but which may also support other radio access technologies, and which may be adapted to implement embodiments of the disclosure as described herein. Various elements of Figure 1 and certain aspects of their respective modes of operation are well-known and defined in the relevant standards administered by the 3GPP (RTM) body, and also described in many books on the subject, for example, Holma H. and Toskala A [1] It will be appreciated that operational aspects of the telecommunications networks discussed herein which are not specifically described (for example in relation to specific communication protocols and physical channels for communicating between different elements) may be implemented in accordance with any known techniques, for example according to the relevant standards and known proposed modifications and additions to the relevant standards.

The network 6 includes a plurality of base stations 1 connected to a core network 2. Each base station provides a coverage area 3 (i.e. a cell) within which data can be communicated to and from communications devices 4. Although each base station 1 is shown in Figure 1 as a single entity, the skilled person will appreciate that some of the functions of the base station may be carried out by disparate, inter-connected elements, such as antennas (or antennae), remote radio heads, amplifiers, etc. Collectively, one or more base stations may form a radio access network.

Data is transmitted from base stations 1 to communications devices 4 within their respective coverage areas 3 via a radio downlink. Data is transmitted from communications devices 4 to the base stations 1 via a radio uplink. The core network 2 routes data to and from the communications devices 4 via the respective base stations 1 and provides functions such as authentication, mobility management, charging and so on. Terminal devices may also be referred to as mobile stations, user equipment (UE), user terminal, mobile radio, communications device, and so forth. Services provided by the core network 2 may include connectivity to the internet or to external telephony services. The core network 2 may further track the location of the communications devices 4 so that it can efficiently contact (i.e. page) the communications devices 4 for transmitting downlink data towards the communications devices 4.

Base stations, which are an example of network infrastructure equipment, may also be referred to as transceiver stations, nodeBs, e-nodeBs, eNB, g-nodeBs, gNB and so forth. In this regard different terminology is often associated with different generations of wireless telecommunications systems for elements providing broadly comparable functionality. However, certain embodiments of the disclosure may be equally implemented in different generations of wireless telecommunications systems, and for simplicity certain terminology may be used regardless of the underlying network architecture. That is to say, the use of a specific term in relation to certain example implementations is not intended to indicate these implementations are limited to a certain generation of network that may be most associated with that particular terminology.

New Radio Access Technology (5G)

An example configuration of a wireless communications network which uses some of the terminology proposed for and used in NR and 5G is shown in Figure 2. In Figure 2 a plurality of transmission and reception points (TRPs) 10 are connected to distributed control units (DUs) 41, 42 by a connection interface represented as a line 16. Each of the TRPs 10 is arranged to transmit and receive signals via a wireless access interface within a radio frequency bandwidth available to the wireless communications network. Thus, within a range for performing radio communications via the wireless access interface, each of the TRPs 10, forms a cell of the wireless communications network as represented by a circle 12. As such, wireless communications devices 14 which are within a radio communications range provided by the cells 12 can transmit and receive signals to and from the TRPs 10 via the wireless access interface. Each of the distributed units 41, 42 are connected to a central unit (CU) 40 (which may be referred to as a controlling node) via an interface 46. The central unit 40 is then connected to the core network 20 which may contain all other functions required to transmit data for communicating to and from the wireless communications devices and the core network 20 may be connected to other networks 30.

The elements of the wireless access network shown in Figure 2 may operate in a similar way to corresponding elements of an LTE network as described with regard to the example of Figure 1. It will be appreciated that operational aspects of the telecommunications network represented in Figure 2, and of other networks discussed herein in accordance with embodiments of the disclosure, which are not specifically described (for example in relation to specific communication protocols and physical channels for communicating between different elements) may be implemented in accordance with any known techniques, for example according to currently used approaches for implementing such operational aspects of wireless telecommunications systems, e.g. in accordance with the relevant standards.

The TRPs 10 of Figure 2 may in part have a corresponding functionality to a base station or eNodeB of an LTE network. Similarly, the communications devices 14 may have a functionality corresponding to the UE devices 4 known for operation with an LTE network. It will be appreciated therefore that operational aspects of a new RAT network (for example in relation to specific communication protocols and physical channels for communicating between different elements) may be different to those known from LTE or other known mobile telecommunications standards. However, it will also be appreciated that each of the core network component, base stations and communications devices of a new RAT network will be functionally similar to, respectively, the core network component, base stations and communications devices of an LTE wireless communications network. In terms of broad top-level functionality, the core network 20 connected to the new RAT telecommunications system represented in Figure 2 may be broadly considered to correspond with the core network 2 represented in Figure 1, and the respective central units 40 and their associated distributed units / TRPs 10 may be broadly considered to provide functionality corresponding to the base stations 1 of Figure 1. The term network infrastructure equipment / access node may be used to encompass these elements and more conventional base station type elements of wireless telecommunications systems. Depending on the application at hand the responsibility for scheduling transmissions which are scheduled on the radio interface between the respective distributed units and the communications devices may lie with the controlling node / central unit and / or the distributed units / TRPs. A communications device 14 is represented in Figure 2 within the coverage area of the first communication cell 12. This communications device 14 may thus exchange signalling with the first central unit 40 in the first communication cell 12 via one of the distributed units / TRPs 10 associated with the first communication cell 12.

It will further be appreciated that Figure 2 represents merely one example of a proposed architecture for a new RAT based telecommunications system in which approaches in accordance with the principles described herein may be adopted, and the functionality disclosed herein may also be applied in respect of wireless telecommunications systems having different architectures.

Thus, certain embodiments of the disclosure as discussed herein may be implemented in wireless telecommunication systems / networks according to various different architectures, such as the example architectures shown in Figures 1 and 2. It will thus be appreciated the specific wireless telecommunications architecture in any given implementation is not of primary significance to the principles described herein. In this regard, certain embodiments of the disclosure may be described generally in the context of communications between network infrastructure equipment / access nodes and a communications device, wherein the specific nature of the network infrastructure equipment / access node and the communications device will depend on the network infrastructure for the implementation at hand. For example, in some scenarios the network infrastructure equipment / access node may comprise a base station, such as an LTE-type base station 1 as shown in Figure 1 which is adapted to provide functionality in accordance with the principles described herein, and in other examples the network infrastructure equipment may comprise a control unit / controlling node 40 and / or a TRP 10 of the kind shown in Figure 2 which is adapted to provide functionality in accordance with the principles described herein.

A more detailed diagram of some of the components of the network shown in Figure 2 is provided by Figure 3. In Figure 3, a TRP 10 as shown in Figure 2 comprises, as a simplified representation, a wireless transmitter 30, a wireless receiver 32 and a controller or controlling processor 34 which may operate to control the transmitter 30 and the wireless receiver 32 to transmit and receive radio signals to one or more UEs 14 within a cell 12 formed by the TRP 10. As shown in Figure 3, an example UE 14 is shown to include a corresponding transmitter 49, a receiver 48 and a controller 44 which is configured to control the transmitter 49 and the receiver 48 to transmit signals representing uplink data to the wireless communications network via the wireless access interface formed by the TRP 10 and to receive downlink data as signals transmitted by the transmitter 30 and received by the receiver 48 in accordance with the conventional operation.

The transmitters 30, 49 and the receivers 32, 48 (as well as other transmitters, receivers and transceivers described in relation to examples and embodiments of the present disclosure) may include radio frequency filters and amplifiers as well as signal processing components and devices in order to transmit and receive radio signals in accordance for example with the 5G/NR standard. The controllers 34, 44 (as well as other controllers described in relation to examples and embodiments of the present disclosure) may be, for example, a microprocessor, a CPU, or a dedicated chipset, etc., configured to carry out instructions which are stored on a computer readable medium, such as a non-volatile memory. The processing steps described herein may be carried out by, for example, a microprocessor in conjunction with a random access memory, operating according to instructions stored on a computer readable medium. The transmitters, the receivers and the controllers are schematically shown in Figure 3 as separate elements for ease of representation. However, it will be appreciated that the functionality of these elements can be provided in various different ways, for example using one or more suitably programmed programmable computer(s), or one or more suitably configured application-specific integrated circuit(s) / circuitry / chip(s) / chipset(s). As will be appreciated the infrastructure equipment / TRP / base station as well as the UE / communications device will in general comprise various other elements associated with its operating functionality.

As shown in Figure 3, the TRP 10 also includes a network interface 50 which connects to the DU 42 via a physical interface 16. The network interface 50 therefore provides a communication link for data and signalling traffic from the TRP 10 via the DU 42 and the CU 40 to the core network 20.

The interface 46 between the DU 42 and the CU 40 is known as the FI interface which can be a physical or a logical interface. The FI interface 46 between CU and DU may operate in accordance with specifications 3GPP TS 38.470 and 3GPP TS 38.473, and may be formed from a fibre optic or other wired or wireless high bandwidth connection. In one example the connection 16 from the TRP 10 to the DU 42 is via fibre optic. The connection between a TRP 10 and the core network 20 can be generally referred to as a backhaul, which comprises the interface 16 from the network interface 50 of the TRP 10 to the DU 42 and the FI interface 46 from the DU 42 to the CU 40. eURLLC and NR-U

Systems incorporating NR technology are expected to support different services (or types of services), which may be characterised by different requirements for latency, data rate and/or reliability. For example, Enhanced Mobile Broadband (eMBB) services are characterised by high capacity with a requirement to support up to 20 Gb/s. The requirements for Ultra Reliable and Low Latency Communications (URLLC) services are for one transmission of a 32 byte packet to be transmitted from the radio protocol layer 2/3 SDU ingress point to the radio protocol layer 2/3 SDU egress point of the radio interface within 1 ms with a reliability of 1 - 10⁵ (99.999 %) or higher (99.9999%) [2]

Massive Machine Type Communications (mMTC) is another example of a service which may be supported by NR-based communications networks. In addition, systems may be expected to support further enhancements related to Industrial Internet of Things (IIoT) in order to support services with new requirements of high availability, high reliability, low latency, and in some cases, high-accuracy positioning. Enhanced URLLC (eURLLC) [3] [4] specifies features that require high reliability and low latency, such as factory automation, transport industry, electrical power distribution, etc.

Another such service incorporating NR technology is 5G NR in Unlicensed Spectrum (NR-U) [5], which enables devices to make use of shared and unlicensed spectrum bandwidth. Such features as Listen Before Talk (LBT), as specified by [5], may be incorporated into the NR frame structure for NR-U operation in unlicensed bands. One of the objectives of eURLLC as laid out in [4] is to introduce UE initiated Channel Occupancy Time (COT) phases in a Semi-Static Channel Access Scheme (also known as Frame Based Equipment) in an unlicensed URLLC operation.

Channel Access in an Unlicensed Band In the following paragraphs, an explanation is provided of current proposals for accessing communications from an unlicensed frequency band. In an unlicensed band, two or more systems may operate to communicate using the same communications resources. As a result, transmissions from different systems can interfere with each other especially when for example, each of the different systems are configured according to different technical standards, for example Wi-Fi (IEEE 802.11-based systems) and 5G. As such, there is a regulatory requirement to use an LBT protocol for each transmitter operating in an unlicensed band to reduce interferences among different systems sharing that band. In LBT, a device that wishes to transmit a packet will firstly sense the band for any energy levels above a threshold to determine if any other device is transmitting, i.e. it listens, and if there is no detected transmission, the device will then transmit its packet. Otherwise, if the device senses a transmission from another device it will back-off and try again at a later time.

In NR-U the channel access can be Dynamic (also known as Load Based Equipment) or Semi-Static (also known as Frame Based Equipment). The dynamic channel access schemes consist of one or more Clear Channel Assessment (CCA) phases 51 in a Contention Window 52 followed by a Channel Occupancy Time (COT) phase 53 as shown Figure 4. LBT is performed during the CCA phase 51 by an NR-U device (e.g. gNB or UE) that wishes to perform a transmission. According to the CCA phase 51, the NR- U device listens to one or more of the CCA slots and if no other transmission is detected (i.e. energy level is determined to be below a threshold for the duration of the one or more CCA slots) after the CCA phase 51, the NR-U device moves into the COT phase 53 where it can transmit its packet in the COT resources. As shown in and described with reference to the drawings of the present disclosure, the term “COT” is used to indicate either a period of time where a UE or infrastructure equipment can potentially transmit, or it is used to indicate a period of time where a UE or infrastructure equipment actually does transmit. The sense in which the term “COT” is used in the description and drawings would be clear to a skilled artisan.

In Dynamic Channel Access (DCA) the CCA 51 and COT 53 phases can be different length between different systems and devices of the same system, whilst in Semi-static Channel Access, the CCA 51 and COT 53 phases have fixed time windows and can be synchronised for all systems sharing the band. Further details on channel access in NR-U may be found in co-pending European patent application with application number EP20187799.0 [6]

In NR-U a device can be an initiating device or a responding device. The initiating device acquires the COT by performing CCA and typically it initiates a first transmission, e.g. a gNB transmits an uplink grant. The responding device receives the transmission from the initiating device and responds with a transmission to the initiating device, e.g. a UE receiving an uplink grant and transmitting the corresponding PUSCH. As will be appreciated a UE can also be an initiating device, for example when it is transmitting a Configured Grant (CG) PUSCH, and the gNB can be a responding device.

A COT can be shared by multiple devices; i.e., a gNB can initiate the COT which it can then share with one or more UE. For example, a gNB can initiate a COT, and then can transmit an UL Grant to a UE, and the UE can then use this COT to transmit the PUSCH. A device using a COT initiated by another device may not need to perform CCA, or may need to perform just a short CCA.

Dynamic Channel Access

There are two types of Dynamic Channel Access (DCA), which are referred to as Type 1 and Type 2. In a Type 1 DCA, a counter N is generated as a random number between 0 and CW_P, where a Contention Window size CW_P is set between CW_min,P and CW_max,P. The duration of the COT and the values {CW_min,p, CW_max,P} depend on the value p, which is the Channel Access Priority Class (CAPC) of the transmission. The CAPC may be determined, for example, by a QoS of the transmitting packet. A Type 1 DCA is performed by an initiating device, and once the COT is acquired, one or more responding devices can use Type 2 DCA for their transmissions within the COT. Type 2 DCA may require a short CCA or no CCA prior to transmission if the gap between one transmission of two devices is less than a predefined value, such as, for example, 25 pis . If the gap is greater than this predefined value such as 25 pis. then the responding device needs to perform Type 1 DCA.

Figure 5 provides an illustration of frequency against time for transmission in an unlicensed band. As shown for the example of Figure 5, an example of a Type 1 DCA transmission and an example of a Type 2 DCA transmission are shown. According to the example shown in Figure 5, at time to, the gNB performs a Type 1 DCA 54 starting with a Contention Window 55 with four CCAs (it should be appreciated that here the number of CCAs N = 4 is merely an example). The gNB detects no energy during the Contention Window 55, thereby acquiring the COT 56 between time t_\ to ts. The gNB then transmits an uplink grant UG1 to the UE scheduling PUSCH1 at time U. The gNB then transmits PDSCH2 to the UE or another UE between time ti and h. The UE receiving UG1 can use Type 2 DCA 57 if the gap between the end of PDSCH2 and the start of its PUSCH1 transmission, i.e. between time h & , is below a threshold. If this is not the case however, the UE will have to perform a Type 1 DCA. Here, it should be noted that the UE’s processing time for UG1 is typically larger than the gap (time h & fi), and so the gNB would normally fill up the channel with other DL transmissions such as PDSCH2 in the example of Figure 5 to the same UE, or to another UE.

There are three types of Type 2 DCA, as shown in Figure 6, which are defined with respect to a length of the gap 61 between transmission 62 by a first device (initiating device) and transmission 64 by a second device (responding device) within a COT, and are therefore defined by whether the second responding device needs to perform a CCA. These types are:

• Type 2A: The gap between two transmissions is not more than 25 pis and is more than 16 ps and the UE performs a single Clear Channel Assessment (CCA) within this gap 61;

• Type 2B: The gap between two transmissions is not more than 16 ps and the UE performs a single CCA within this gap 61 ; and

• Type 2C: The gap between two transmissions is not more than 16 ps and no CCA is required within this gap 61.

Semi-static Channel Access

In Semi-static Channel Access (SCA), a Fixed Frame Period (FFP) is defined for COT initiation. The FFP 71 consists of a COT period 72 and an Idle period 73 at the end, as shown in Figure 7. The CCA 74 (e.g. LBT) is required prior to an initiation of a COT 72, and it is performed during the Idle period 73.

The COT period 72 of the FFP exists irrespective of whether the CCA succeeds or not. If the CCA is successful for a device, the device initiates a COT within the COT period. If the CCA is not successful, the device does not initiate a COT within the COT period. In Rel-16 NR-U, FFP is defined for the gNB and its parameters; i.e. an offset (relative to the start of radio frame SFN=0) and a period (duration of the FFP), are configurable and are broadcast in SIB 1. The FFP parameters can be reconfigured every 200 ms after they have been used; i.e. once the gNB has transmitted using a FFP configuration, it must maintain that configuration for at least 200 ms before it can be reconfigured (if required). In Rel-16, though either a gNB or a UE may have something to transmit, and thus performs LBT during the CCA, it is only the gNB that can initiate a COT under a Semi-Static Channel Access operation. Semi-static Channel Access is used in a controlled environment where the deployed unlicensed network is not expected to be interfered with by another unlicensed system. For example, an unlicensed network may be deployed using SCA in a factory where other unlicensed systems such as Wi-Fi are not deployed. In such an environment, the FFP of each gNB in the network can be aligned and synchronised, thereby allowing it to operate like a licensed band. An example is shown in Figure 8, where gNBl and gNB2 are deployed in a controlled environment, e.g. a factory, and they operate in an unlicensed band using Semi- Static Channel Access. The FFPs for both gNBs are configured to be aligned such that their FFP idle periods 81, 82 occur at the same time. Hence, with this arrangement, the gNBs would be unlikely to detect any energy during their CCA phases 83, 84 since both gNBl and gNB2 would not transmit during each other’s CCA phase 83, 84. This allows the system to satisfy regulatory requirements for LBT and also enable the gNB’s scheduler to operate in a predictable manner; i.e. similar to a licensed band operation.

UE Initiated COT in Rel 17

In Rel- 17, UE initiated COT is introduced for Semi-static Channel Access (SCA) where a UE FFP is defined. It was agreed that the UE FFP can be RRC configured (it is configurable and changeable) and may be RRC configured to have a different offset and period to the gNB’s FFP, or to other UEs’ FFPs.

An example is shown in Figure 9, where there is an offset 91 between the start of the gNB’s FFP and the UE’s FFP. The gNB FFP period is P_gm and the UE FFP period is configured to be PUE where P_gm is different to PUE (in this case P_g > PUE). While the gNB would be able to align the COTs of the gNB and UE and thus make offset 91 zero, doing so would essentially prevent the UE from controlling its own COT when initiating it.

When a device initiates a COT, it transmits according to its FFP frame. Taking the example shown by Figure 9, if the gNB initiates a COT, it shall transmit in the gNB’s COT within its FFP period P_gNB. Similarly, if the UE initiates a COT, it shall transmit in the UE’s COT within its FFP period PUE. However, it has been suggested in [7] and [8] that the UE should not transmit during the gNB’s FFP idle period even when the UE has initiated a COT. That is, in addition to the UE’s own FFP idle period, the UE should also not transmit within gNB’s idle period. In [7], it is argued that a UE’s transmission during the gNB FFP idle period would cause interference to other gNBs during their CCA phase thereby preventing them from accessing the channel since in Semi-Static Channel Access under a controlled environment, the gNBs’ FFPs are synchronised. In [8], it is suggested that this additional constraint on the UE initiated COT transmission allows the gNB to initiate a COT whilst still under a UE initiated COT.

An example is shown in Figure 10, where the UE’s FFP is offset to that of the gNB. At time i_\. the UE performed LBT in the CCA phase and successfully initiated a COT that extends from time h to A The UE transmits a PUSCH at time h. As per the proposals described in [7] and [8], the UE stops transmitting during the gNB’s idle period between time h and A This allows the gNB to perform LBT during its CCA phase between time t_\ and ts and initiate a COT that starts from time ts to h without interfering signals being transmitted by the UE. After initiating the COT, the gNB transmits a DCI, e.g. a DL Grant to another UE, between time ts and Hence, it is possible that the gNB initiates a COT whilst still under the UE’s COT, due to this offset between the UE’s and gNB’s FFP periods.

Two issues may be identified regarding whether or not a UE is able to transmit under its own FFP, when offset with a gNB’s FFP, after the gNB’s FFP idle period but before its own FFP idle period (i.e. the period between times C and h, as shown in Figure 10). If the UE is allowed to transmit after the gNB’s FFP idle period, then the UE may interfere with the gNB’s transmission if the gNB decides to initiate its own COT. An example is shown in Figure 11, where the UE initiated a COT at time h_ and transmits PUSCH1 between time h_ to h and stops its transmission during the gNB’s FFP idle period between time h and A The gNB initiates a COT and transmits a DCI between time ts and h and here the UE also transmits PUSCH2 at ts until the end of its COT at time , thereby colliding 110 with the gNB’s transmission, which is not desirable. Because such systems as that shown in Figure 11 operate in accordance with Time Division Duplexing (TDD), where both the gNB and UE transmit in the same frequency band, collisions in time will prevent the signals involved in the collision from being received correctly.

If the UE is not allowed to transmit after the gNB’s FFP idle period, then if the gNB initiates a COT, its transmission would not collide with that of the UE. However, when the gNB and UE COTs are offset, preventing the UE from transmitting after the gNB’s FFP idle period would reduce the COT duration of the UE, i.e. reducing its transmission opportunity. An example is shown in Figure 12, where once again the UE initiated a COT and transmits a PUSCH between time C to h, i.e. until the start of gNB’s FFP idle period at time h. if the UE is not allowed to transmit after the gNB’s FFP idle period, i.e. between time ts and it, then the UE’s COT is reduced from between h and it, to being between h and h as illustrated by region 120. Since the gNB did not actually initiate any COT here, the portion 120 of the UE’s COT between time ts and is unused and wasted, as neither the UE nor the gNB are transmitting signals during that period 120. In NR systems, particularly in low-latency applications, unused resource is particularly undesirable. The amount of reduction in the UE’s COT depends on the position of the gNB’s FFP idle period relative to the UE’s FFP, which can be significant.

Hence, a technical issue to solve is to allow the gNB to initiate a COT within a UE’s COT without collision with the UE’s transmission, yet in a way that avoids reducing the UE’s COT in times when the gNB does not initiate a COT. Embodiments of the present disclosure propose solutions to such an issue, by making better use of resources but in a manner which avoids collisions between transmissions from a UE and a gNB.

UE Transmission After gNB’s FFP Idle Period

Figure 13 shows a part schematic, part message flow diagram representation of a wireless communications network comprising a communications device 131 and an infrastructure equipment 132 in accordance with at least some embodiments of the present technique. The communications device 131 is configured to transmit signals to and/or receive signals from the wireless communications network, for example, to and from the infrastructure equipment 132, within communications resources of an unlicensed channel of a wireless access interface provided by the wireless communications network. Specifically, the communications device 131 may be configured to transmit data to the wireless communications network (e.g. to the infrastructure equipment 132) via the wireless access interface. The communications device 131 and the infrastructure equipment 132 each comprise a transceiver (or transceiver circuitry) 131.1, 132.1, and a controller (or controller circuitry) 131.2, 132.2. Each of the controllers 131.2, 132.2 may be, for example, a microprocessor, a CPU, or a dedicated chipset, etc.

As shown in the example of Figure 13, the transceiver circuitry 131.1 and the controller circuitry 131.2 of the communications device 131 are configured in combination to transmit 134 a first portion of data to the wireless communications network (e.g. to the infrastructure equipment 132) in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network (e.g. of the infrastructure equipment 132)), determining 135 whether the communications device 131 can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network (e.g. of the infrastructure equipment 132) used by the wireless communications network (e.g. by the infrastructure equipment 132) for transmitting signals to the communications device 131 in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data, and, in accordance with the determination 135, either to transmit 136 the second portion of the data to the wireless communications network (e.g. to the infrastructure equipment 132) in the overlap region, or to refrain from restarting the transmission 137 of the data to the wireless communications network (e.g. to the infrastructure equipment 132) in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Here, in some arrangements of embodiments of the present disclosure, the UE’s FFP may be offset in time from the gNB’s FFP and/or the UE’s FFP and the gNB’s FFP may have different FFP periods.

While the example of Figure 13 shows the communications device 131 transmitting the data to the wireless communications network (e.g. to the infrastructure equipment 132), those skilled in the art would appreciate that embodiments of the present technique would equally and similarly apply to cases where the communications device 131 may alternatively be transmitting data to, for example, another communications device via a sidelink.

Essentially, embodiments of the present technique propose that the gNB indicates to the UE (or the UE otherwise determines) whether the UE can continue to transmit after the gNB’s FFP idle period or whether the UE should stop its transmission at this point. The gNB can indicate to the UE to stop its transmission after the gNB’s FFP idle period if the gNB wishes to initiate a COT, thereby avoiding colliding with the UE’s transmission. If the gNB does not wish to initiate a COT, it can indicate to the UE to continue its transmission (if any) after the gNB’s FFP idle period, thereby minimising any reduction in the UE’s COT duration and ensuring efficient resource usage. Such an indication can be dynamic or semi-static.

In some arrangements of embodiments of the present disclosure, the said indication is used if the UE is configured not to transmit in the gNB’s FFP idle period. This recognises that in known solutions, for example in [8], it is proposed that the UE can be configured to either transmit or not transmit during the gNB’s FFP idle period when the UE has itself initiated a COT. If the UE is configured to transmit during the gNB’s FFP idle period, then the said indication is therefore not required. On the other hand, if it is fixed in the specifications or it is configured that the UE cannot transmit during the gNB’s FFP idle period, then this indication will be used. In other words, in such arrangements, the determination is made by the communications device if the communications device determines that it is not able to transmit the second portion of the data during the idle period of the FFP of the wireless communications network.

In some arrangements of embodiments of the present disclosure, which are described below with reference to Figures 14 to 19, the gNB may dynamically indicate to the UE, either explicitly or implicitly, whether or not it can transmit after the gNB’s FFP idle period. In other words, the determination is made by the communications device based on an indication received from the wireless communications network.

In an arrangement of embodiments of the present technique, a silence period P _after is introduced after the gNB’s FFP idle period where the UE does not transmit. During this period P _afte , the gNB can indicate to the UE whether it is allowed to transmit after P _after has ended. In other words, the indication is received from the wireless communications network within a silence period of the COT period of the communications device, wherein the silence period is located at the start of the overlap region and beginning at the end of the idle period of the FFP of the wireless communications network. This silence period and its parameters (e.g. duration of P _after) can be RRC configured or fixed in the specifications.

In an arrangement of embodiments of the present disclosure, the said indicator used during the said silence period P _afte may be an explicit indicator, which indicates to the UE that it is allowed to continue to transmit data after the gNB’s FFP idle period. Alternatively, this explicit indicator may indicate to the UE that it is not allowed to continue to transmit data after the end of the gNB’s FFP idle period. In other words, based on receiving the indication, the communications device either determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region, or the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network. This explicit indicator can be transmitted using a DCI, GC-DCI (Group Common DCI) or a sequence such as a DMRS. For an example, if a Slot Format Indicator (SFI) carried by GC-DCI is indicated as “downlink” on a UE’s remaining COT duration after the gNB’s FFP idle period, the UE recognises that it is not allowed to continue to transmit data during this remaining COT duration.

An example is shown in Figure 14, where the UE initiates a COT at time i i and transmits PUSCH1 at time C- The UE stops its transmission during the gNB’s FFP idle period between time h and A The UE further refrains from transmitting after the gNB’s FFP idle period during the said silence period P _afte 141 duration between time ts and it,: i.e. during a first portion of the overlap region 142. During the period P _after, the gNB sends an explicit indicator via a DCI to the UE and in this example, the gNB did not initiate a COT and so it indicates to the UE that it can continue to transmit in the remaining part of its COT, i.e. between time t₍, to h i.e. during a second portion of the overlap region 142. The UE then decides to transmit PUSCH2 between time it, to h. It should be appreciated that the UE may not transmit anything even if the gNB allows it, e.g. if the UE has no further uplink traffic. Furthermore, it should be appreciated that while the example of Figure 14 shows that PUSCH2 is transmitted at time U, directly after the reception of the DCI during the period P _after, there may be a gap in time between the DCI and PUSCH2. In other words, the time taken to transmit the DCI may be less than the duration of P _after, and this may allow the UE time to decode the DCI before transmission of PUSCH2.

In an arrangement of embodiments of the present disclosure, the said indicator used during the said silence period P _after is an implicit indicator. Here the UE determines that the gNB allows it to transmit after if the UE does not detect any transmission from the gNB, otherwise it refrains from transmission. However, the UE may alternatively determine that it is not allowed to transmit after P _after if the UE detects any transmission from the gNB during this time. In other words, based on not receiving the indication within the silence period of the COT period of the communications device, the communications device either determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region or the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network. The gNB’s transmission during P _after does not need to be a message to the UE that initiated the COT and it can be a message to other UEs or a broadcast message such as SIB. It should be noted here that this message can be longer than P _after, e.g. a PDSCH to a UE. That is to say, if the UE detects any transmission from the gNB during P _after, it is an implicit indication that the UE is not allowed to transmit (or alternatively in some cases, that the UE is allowed to transmit) and an absence of any gNB’s transmission implicitly indicates that the UE is allowed to transmit (or in some cases, that it is not). An example is shown in Figure 15, where the UE initiates a COT and transmits PUSCH1 at time h_. The UE stops its transmission during the gNB’s FFP idle period and refrains from transmitting for a further P _after, i.e. the silence period 151. During P _after, i.e. between time ri and it, (the first half of the overlap region 152), the UE monitors for any transmission from the gNB. In this example, the gNB did not make any transmission and thus the absence of any gNB transmission implicitly indicates to the UE that it can transmit in the remaining portion of its COT, i.e. between time it, and ii. where it transmits PUSCH2.

In an arrangement of embodiments of the present disclosure, a silence period

is introduced before the gNB’s FFP idle period where the UE does not transmit. In other words, the indication is received from the wireless communications network within a silence period of the COT period of the communications device, wherein the silence period is located outside of the overlap region and ending before the beginning of the idle period of the FFP of the wireless communications network. During this period P _before, the gNB can indicate to the UE whether it is allowed to transmit after the gNB’s FFP idle period has ended. This said silence period and its parameters (e.g. duration of P_{befo e}) can be RRC configured or fixed in the specifications.

In an arrangement of embodiments of the present disclosure, the said indicator used during the said silence period P_before is an explicit indicator, where this explicit indicator works in a similar manner as that described for the silence period described above and with reference to the example of Figure 14. That is, based on receiving the indication, the communications device either determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region, or the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network. This explicit indicator can be transmitted using a DCI, GC-DCI (Group Common DCI) or a sequence such as a DMRS.

An example is shown in Figure 16, where the UE initiates a COT and transmits PUSCH1 at time h. The UE stops its transmission at time h, i.e. P_before (i.e. the silence period) 161 before the gNB’s FFP idle period. The gNB transmits an explicit indicator during P_before, between time h and ri, to indicate that the UE is not allowed to transmit after the gNB’s FFP Idle Period. The gNB initiates a COT and transmits a DL Grant at time t₍, to schedule PDSCH1 at time h to i_f. i.e. in the overlap period 162.

In an arrangement of embodiments of the present disclosure, the said indicator used during the said silence period P_before is an implicit indicator, where this implicit indicator works in a similar manner as that described for the silence period P _after described above and with reference to the example of Figure 14. That is, based on not receiving the indication within the silence period of the COT period of the communications device, the communications device either determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region or the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network. Here the UE determines that the gNB allows it to transmit after the gNB’s FFP idle period if the UE does not detect any transmission from the gNB otherwise it refrains from transmission. The gNB’s transmission during P_before does not need to be a message to the UE that initiated the COT and it can be a message to other UEs or a broadcast message such as SIB.

An example is shown in Figure 17, where the UE initiates a COT and transmits PUSCH1 at time h_. The UE stops transmitting at time h, i.e. P _{befo e} (i.e. the silence period) 171 prior to the gNB’s FFP idle period. During P _before i.e. between time h and U, the gNB transmits a DL Grant to schedule PDSCH1 between time it, to h. The UE detecting the presence of transmission from the gNB during P_before, implicitly determines that the UE is not allowed to transmit after gNB’s FFP idle period, i.e. in the remaining portion of its COT between time to to h i.e. the overlap period 172. It should be noted here that the DL Grant and PDSCH1 can be targeted at a different UE or the same UE that had initiated the COT.

In an arrangement of embodiments of the present technique, the gNB indicates whether a UE is allowed to transmit in a gNB’s FFP idle period in an UL Grant or a DL Grant, where the scheduled PUSCH by the UL Grant or the PUCCH by the DL Grant starts at the beginning of the UE’s FFP. In other words, the indication is received within a resource grant for a signal to be transmitted by the communications device within the first set of communications resources. Here the UE may initiate a COT to transmit the scheduled uplink transmission, e.g. by a command in the UL Grant or DL Grant or implicitly.

An example is shown in Figure 18, where the gNB initiates a COT and transmits an UL Grant 181 to the UE at time to. The UL Grant 181 schedules PUSCH1 to transmit at time h and indicates to the UE to initiate a COT prior to transmitting PUSCH1. Here the UL Grant 181 also tells the UE not to transmit after the gNB’s FFP idle period in the remaining portion of its COT between time to to , i.e. in the overlap region 182. The gNB initiates another COT at time It, and transmits a DL Grant to schedule PDSCH1 to another UE.

In an arrangement of embodiments of the present technique, the said UL Grant or DL Grant that indicates to the UE to initiate a COT can also tell the UE whether it can transmit during the gNB’s FFP idle period. In other words, the indication further indicates whether or not the communications device can transmit the first portion of the data in a region of the first set of communications resources that overlaps with the idle period of the FFP of the wireless communications network. Using the example in Figure 18, the UL Grant 181 at time to can indicate whether the UE can transmit during the gNB’s FFP idle period between time h to It, or not.

In an arrangement of embodiments of the present technique, the DFI (Downlink Feedback Information) is used to indicate (explicitly or implicitly) whether the UE is allowed to transmit after the gNB’s FFP idle period. In other words, the indication is received within a downlink feedback information, DFI, signal, the DFI comprising feedback from the wireless communications network for signals transmitted by the communications device to the wireless communications network.

The DFI is used to feedback HARQ-ACK to the UE’s CG-PUSCH (CG = “configured grant”) transmissions in an unlicensed band. If the CG-PUSCH consists of repetitions, the DFI can be used to terminate the repetitions, e.g. by sending an ACK prior to the completion of the set of repetitions. In this arrangement, the UE has a set of PUSCH repetitions that extends after the gNB’s FFP idle period and if the DFI indicates prior to the completion of the set of repetitions that the gNB has received the PUSCH, the UE will then terminate the remaining repetitions. Since the repetitions extend beyond the gNB’s FFP idle period, such termination would also implicitly indicate that the UE should not transmit after the gNB’s FFP idle period.

An example is shown in Figure 19, where the UE initiates a COT and transmits CG-PUSCH with 4 repetitions at time h. which are labeled as #1, #2, #3 and #4. PUSCH repetitions #3 and #4 occur after the gNB’s FFP idle period, which is between time ri to h. After the 2^nd PUSCH repetition i.e. PUSCH #2, the gNB transmits a DFI 191 indicating an ACK for the PUSCH thereby terminating the set of repetitions. Since the remaining repetitions occur after the gNB’s FFP idle period, the UE refrains from transmitting in that remaining portion of the COT between time h to rii; i.e. during the overlap region 192. The DFI 191 therefore implicitly indicates that the UE should not transmit after the gNB’s FFP idle period and here the gNB initiates its own COT and transmit a DF Grant at time U>. to schedule PDSCH1.

In an arrangement where the CG-PUSCH repetitions extend beyond the overlapping gNB’s FFP idle period, the presence of a DFI prior to the gNB’s FFP idle period would indicate that the UE cannot transmit after the gNB’s FFP idle period regardless of whether the DFI indicates an ACK or a NACK. If the UE detects the absence of a DFI, then this implicitly indicates that the UE can transmit after the gNB’s FFP idle period. In other words, wherein the indication comprises whether or not a DFI signal is received by the communications device. This UE behaviour of using presence and absence of DFI to determine whether it can or cannot transmit after the gNB’s FFP idle period can be RRC configured.

In an arrangement of embodiments of the present technique the gNB indicates using Group Common-DCI (GC-DCI) whether a group of UEs can transmit after the gNB’s FFP idle period or not. In other words, the indication is received within downlink control information, DCI, the DCI being common for the communications device and one or more other communications devices.

In some arrangements of embodiments of the present disclosure, as described below, the indication received by the UE relating to whether or not it is allowed to transmit following the idle period of the gNB’s FFP is a semi-static indication. Here, in at least one such arrangement, the gNB may RRC configure whether the UE is allowed to transmit after the gNB’s FFP idle period or not. In other words, the determination is made by the communications device based on a Radio Resource Control, RRC, configuration signal received from the wireless communications network. This RRC configuration can be UE specific (i.e. the RRC configuration signal is transmitted specifically to the communications device by the wireless communications network).

In an arrangement of embodiments of the present technique, the gNB can broadcast using RRC signalling to, for example, a group of UEs, whether these UEs can transmit after the gNB’s FFP idle period or not.

In other words, the RRC configuration signal is broadcast by the wireless communications network and is receivable by the communications device and optionally is receivable by one or more other communications devices.

Here, it will be appreciated by those skilled in the art that this broadcasting or RRC configuring is done so for a longer period rather than on a per-FFP basis. Such a semi-static configuration is therefore valid for a certain period (e.g. a period of time, a number of FFPs, an indefinite period that may last until indicated otherwise or overridden, etc.). In some arrangements of embodiments of the present technique however, the gNB configures the UE via semi-static signalling a default behaviour. In other words, the RRC configuration signal indicates whether or not the communications device can transmit the second portion of the data in the overlap region of the first set of communications resources as a default configuration, and the RRC configuration signal may indicate that the default configuration may be overridden by a later indication dynamically received by the communications device from the wireless communications network. That is, the UE may be allowed to transmit (or alternatively may be prevented from transmitting) after the gNB’s FFP idle period, but this can be overridden by the gNB dynamically for each occurrence individually or for M occurrences where the gNB’s FFP idle period overlaps with a UE initiated COT. It would be understood by the skilled person that the gNB can use any one or more of the herein described dynamic configuration examples described with respect to Figures 14 to 19 to override the configured default behaviour, though it should be appreciated that such examples are not limiting here.

In some arrangements of embodiments of the present disclosure, the UE may determine whether it can transmit after the gNB’s FFP idle period based on the duration of the remaining portion of its COT, T_remam· Here, it can be understood that is essentially the period of the overlap region, assuming that the remaining portion of the UE’s COT after the idle period of the gNB’s FFP period is not longer than the gNB’s entire next COT after that idle period. Thus, the determination may be made by the communications device based on the duration of the overlap region.

In an arrangement of embodiments of the present disclosure, if the

portion is less than a threshold X, the UE does not transmit after the gNB’s FFP idle period, otherwise it can transmit. In other words, if the duration of the overlap region is less than a threshold time, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network, and if the duration of the overlap region is greater than a threshold time, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region. This arrangement recognises that if the remaining portion of the COT is small, it may not contain sufficient resource for the UE to make a reliable transmission and so the UE ceases transmitting to reduce interference. That is, the UE effectively determines that there is not much point continuing its own transmission in this COT, and doing so would impact the gNB’s transmission. The value of can be RRC configured or fixed in the specifications.

An example is shown in Figure 20, where the UE initiates a COT and transmits PUSCH1 at time h. The UE stops its transmission at time h, before the start of the gNB’s FFP idle period between time h and A In this example, the remaining portion 201 (i.e. the overlap portion) of the UE’s COT which lasts for time T_remain 202, i.e. between time ts and l_<„ is below a configured threshold Hence, the UE does not transmit after the gNB’s FFP idle period.

In some arrangements of embodiments of the present technique, the UE may indicate (e.g. via a request) whether it wishes to transmit after the gNB’s FFP idle period. The said UE request indication can be a CG-UCI in a CG-PUSCH, a UCI piggybacked onto a DG-PUSCH, or carried by a PUCCH, e.g. an SR (Scheduling Request). The gNB can then decide whether to grant the UE access to the remaining portion of its COT or initiate its own COT and share that COT with the UE, and respond accordingly.

In some such arrangements of embodiments of the present technique, after the UE indicates that it wishes to transmit after the gNB’s FFP idle period, the UE monitors for a response from the gNB within a pre determined time period T_respome· In other words, the determination is made by the communications device based on a response from the wireless communications network monitored for by the communications device within a predetermined response period, the response being to a request transmitted by the communications device to the wireless communications network to transmit the second portion of the data in the overlap region. The time period 7

can be configured in various ways, as shown by the examples in Figures 21, 22, and 23.

In some arrangements, 7 may start prior to the gNB’s FFP idle period and ends at the start of gNB’s FFP idle period. In other words, the predetermined response period starts and ends before the beginning of the idle period of the FFP of the wireless communications network. An example is shown in Figure 21, where the UE transmits a request 211 as a UCI piggybacked onto a PUSCH after it has initiated a COT at time t , to request for transmission after the gNB’s FFP idle period. Here the predetermined response period T_response 212 is between time t_\ and U,. where the gNB responds 213 with a DCI to indicate whether it allows or not allows the UE to transmit after the gNB’s FFP idle period in the overlap region 214.

In some arrangements, T_resp0me may start prior to the gNB’s FFP idle period and ends after the gNB’s FFP idle period but before the end of the UE’s (initiated) COT. In other words, the predetermined response period starts before the beginning of the idle period of the FFP of the wireless communications network and ends after the end of the idle period of the FFP of the wireless communications network but before the end of the COT period of the communications device. An example is shown in Figure 22, where after the UE sends a request 221, it monitors for the gNB’s response 223 within the predetermined response period T_response 223 that is between u to U>. which indicates whether it allows or not allows the UE to transmit after the gNB’s FFP idle period in the overlap region 224.

In some arrangements, //„_/«»«- may start after the gNB’s FFP idle period and ends before the UE’s (initiated) COT. In other words, the predetermined response period starts after the end of the idle period of the FFP of the wireless communications network and ends before the end of the COT period of the communications device. An example is shown in Figure 23, where after the UE sends a request 231, it monitors for a response 233 from the gNB after the gNB’s FFP idle period between time h to U>. in the predetermined response period 232, which indicates whether it allows or not allows the UE to transmit after the gNB’s FFP idle period in the overlap region 234. It should be noted here that the UE can perform other transmissions after its PUSCH and before the gNB’s FFP idle period, i.e. it can perform other transmission between time h to ; the skilled person would understand that the operations shown by Figures 21 to 23 are merely examples.

In an arrangement of embodiments of the present disclosure, the said response from the gNB within time period T_reSponse is explicit, i.e. whether the gNB allows or not allows the UE to transmit is explicitly indicated, e.g. in a DCI. In other words, if the response is received within the predetermined response period, the communications device either determines based on this response that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region or the communications device determines based on this response that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

In an arrangement of embodiments of the present disclosure, an absence of a gNB’s response within time T_response, indicates that the UE can transmit after the gNB’s FFP idle period. In other words, if the response is not received within the predetermined response period, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region. If the UE does however receive a response from the gNB then it means the UE cannot transmit after the gNB’s FFP idle period.

In an arrangement of embodiments of the present disclosure, an absence of a gNB’s response within time T_response, indicates that the UE cannot transmit after the gNB’s FFP idle period. In other words, if the response is not received within the predetermined response period, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network. If the UE does however receive a response from the gNB then it means the UE can transmit after the gNB’s FFP idle period.

Figure 24 shows a flow diagram illustrating a first example process of communications in a communications system in accordance with embodiments of the present technique. The process shown by Figure 24 is a method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network (e.g. to or from an infrastructure equipment of the wireless communications network within communications resources of an unlicensed channel of a wireless access interface). The method begins in step SI. The method comprises, in step S2, transmitting a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network. In step S3, the process comprises determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data. In accordance with the determination made in step S3, the method then comprises either transmitting the second portion of the data in the overlap region in step S4, or refraining from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network in step S5. The process ends in step S6.

Those skilled in the art would appreciate that the method shown by Figure 24 may be adapted in accordance with embodiments of the present technique. For example, other intermediate steps may be included in the method, or the steps may be performed in any logical order.

Though embodiments of the present technique have been described largely by way of the example communications system shown in Figure 13, and described by way of the arrangements shown by Figures 14 to 23, it would be clear to those skilled in the art that they could be equally applied to other systems to those described herein.

Those skilled in the art would further appreciate that such infrastructure equipment and/or communications devices as herein defined may be further defined in accordance with the various arrangements and embodiments discussed in the preceding paragraphs. It would be further appreciated by those skilled in the art that such infrastructure equipment and communications devices as herein defined and described may form part of communications systems other than those defined by the present disclosure.

The following numbered paragraphs provide further example aspects and features of the present technique:

Paragraph 1. A method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface, the method comprising transmitting a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data, and, in accordance with the determination, either transmitting the second portion of the data in the overlap region, or refraining from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 2. A method according to Paragraph 1, wherein the determination is made by the communications device if the communications device determines that it is not able to transmit the second portion of the data during the idle period of the FFP of the wireless communications network.

Paragraph 3. A method according to Paragraph 1 or Paragraph 2, wherein the determination is made by the communications device based on an indication received from the wireless communications network. Paragraph 4. A method according to Paragraph 3, wherein, based on receiving the indication, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

Paragraph 5. A method according to Paragraph 3 or Paragraph 4, wherein, based on receiving the indication, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 6. A method according to any of Paragraphs 3 to 5, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

Paragraph 7. A method according to any of Paragraphs 3 to 6, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 8. A method according to any of Paragraphs 3 to 7, wherein the indication is received from the wireless communications network within a silence period of the COT period of the communications device.

Paragraph 9. A method according to any of Paragraphs 6 to 8, wherein the silence period is located at the start of the overlap region and beginning at the end of the idle period of the FFP of the wireless communications network. Paragraph 10. A method according to any of Paragraph 6 to 8, wherein the silence period is located outside of the overlap region and ending before the beginning of the idle period of the FFP of the wireless communications network.

Paragraph 11. A method according to any of Paragraphs 3 to 10, wherein the indication is received within a resource grant for a signal to be transmitted by the communications device within the first set of communications resources.

Paragraph 12. A method according to Paragraph 11, wherein the indication further indicates whether or not the communications device can transmit the first portion of the data in a region of the first set of communications resources that overlaps with the idle period of the FFP of the wireless communications network.

Paragraph 13. A method according to any of Paragraphs 3 to 12, wherein the indication is received within a downlink feedback information, DFI, signal, the DFI comprising feedback from the wireless communications network for signals transmitted by the communications device to the wireless communications network.

Paragraph 14. A method according to any of Paragraphs 3 to 13, wherein the indication comprises whether or not a DFI signal is received by the communications device.

Paragraph 15. A method according to any of Paragraphs 3 to 14, wherein the indication is received within downlink control information, DCI, the DCI being common for the communications device and one or more other communications devices.

Paragraph 16. A method according to any of Paragraphs 1 to 15, wherein the determination is made by the communications device based on a Radio Resource Control, RRC, configuration signal received from the wireless communications network.

Paragraph 17. A method according to Paragraph 16, wherein the RRC configuration signal is transmitted specifically to the communications device by the wireless communications network.

Paragraph 18. A method according to Paragraph 16 or Paragraph 17, wherein the RRC configuration signal is broadcast by the wireless communications network and is receivable by the communications device and one or more other communications devices.

Paragraph 19. A method according to any of Paragraphs 16 to 18, wherein the RRC configuration signal indicates whether or not the communications device can transmit the second portion of the data in the overlap region of the first set of communications resources as a default configuration.

Paragraph 20. A method according to Paragraph 19, wherein the RRC configuration signal indicates that the default configuration may be overridden by a later indication dynamically received by the communications device from the wireless communications network.

Paragraph 21. A method according to any of Paragraphs 1 to 20, wherein the determination is made by the communications device based on the duration of the overlap region.

Paragraph 22. A method according to Paragraph 21, wherein if the duration of the overlap region is less than a threshold time, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 23. A method according to Paragraph 21 or Paragraph 22, wherein if the duration of the overlap region is greater than a threshold time, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region. Paragraph 24. A method according to any of Paragraphs 1 to 23, wherein the determination is made by the communications device based on a response from the wireless communications network monitored for by the communications device within a predetermined response period, the response being to a request transmitted by the communications device to the wireless communications network to transmit the second portion of the data in the overlap region.

Paragraph 25. A method according to Paragraph 24, wherein the predetermined response period starts and ends before the beginning of the idle period of the FFP of the wireless communications network. Paragraph 26. A method according to Paragraph 24 or Paragraph 25, wherein the predetermined response period starts before the beginning of the idle period of the FFP of the wireless communications network and ends after the end of the idle period of the FFP of the wireless communications network but before the end of the COT period of the communications device.

Paragraph 27. A method according to any of Paragraphs 24 to 26, wherein the predetermined response period starts after the end of the idle period of the FFP of the wireless communications network and ends before the end of the COT period of the communications device.

Paragraph 28. A method according to any of Paragraphs 24 to 27, wherein if the response is received within the predetermined response period, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

Paragraph 29. A method according to any of Paragraphs 24 to 28, wherein if the response is received within the predetermined response period, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 30. A method according to any of Paragraphs 24 to 29, wherein if the response is not received within the predetermined response period, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region. Paragraph 31. A method according to any of Paragraphs 24 to 30, wherein if the response is not received within the predetermined response period, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 32. A communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface, the communications device comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface, and controller circuitry configured in combination with the transceiver circuitry to transmit a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data, and, in accordance with the determination, either to transmit the second portion of the data in the overlap region, or to refrain from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 33. Circuitry for a communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface, the circuitry comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface, and controller circuitry configured in combination with the transceiver circuitry to transmit a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data, and, in accordance with the determination, either to transmit the second portion of the data in the overlap region, or to refrain from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 34. A method of operating an infrastructure equipment forming part of a wireless communications network configured to transmit signals to and/or to receive signals from a communications device within communications resources of an unlicensed channel of a wireless access interface, the method comprising receiving a first portion of data from the communications device in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the infrastructure equipment stops reception of the data, and, in accordance with the determination, either receiving the second portion of the data from the communications device in the overlap region, or determining that the communications device has refrained from restarting transmission of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 35. A method according to Paragraph 34, wherein the infrastructure equipment stops the reception of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network only if the infrastructure equipment did not schedule any signals to be transmitted by the communications device in the overlap region.

Paragraph 36. A method according to Paragraph 34 or Paragraph 35, wherein the determination is made by the infrastructure equipment if the infrastructure equipment determines that the communications device is not able to transmit the second portion of the data during the idle period of the FFP of the wireless communications network.

Paragraph 37. A method according to any of Paragraphs 34 to 36, wherein the determination is made by the infrastructure equipment based on an indication transmitted to the communications device by the infrastructure equipment. Paragraph 38. A method according to Paragraph 37, wherein, based on transmitting the indication, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

Paragraph 39. A method according to Paragraph 37 or Paragraph 38, wherein, based on receiving the indication, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 40. A method according to any of Paragraphs 37 to 39, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

Paragraph 41. A method according to any of Paragraphs 37 to 40, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 42. A method according to any of Paragraphs 37 to 41, wherein the indication is transmitted to the communications device within a silence period of the COT period of the communications device. Paragraph 43. A method according to any of Paragraph 40 to 42, wherein the silence period is located at the start of the overlap region and beginning at the end of the idle period of the FFP of the wireless communications network.

Paragraph 44. A method according to any of Paragraph 40 to 42, wherein the silence period is located outside of the overlap region and ending before the beginning of the idle period of the FFP of the wireless communications network.

Paragraph 45. A method according to any of Paragraphs 37 to 44, wherein the indication is transmitted within a resource grant for a signal to be transmitted by the communications device within the first set of communications resources.

Paragraph 46. A method according to Paragraph 45, wherein the indication further indicates whether or not the communications device can transmit the first portion of the data in a region of the first set of communications resources that overlaps with the idle period of the FFP of the wireless communications network.

Paragraph 47. A method according to any of Paragraphs 37 to 46, wherein the indication is transmitted within a downlink feedback information, DFI, signal, the DFI comprising feedback from the infrastructure equipment for signals received by the infrastructure equipment from the communications device.

Paragraph 48. A method according to any of Paragraphs 37 to 47, wherein the indication comprises whether or not a DFI signal is received by the communications device.

Paragraph 49. A method according to any of Paragraphs 37 to 48, wherein the indication is transmitted within downlink control information, DCI, the DCI being common for the communications device and one or more other communications devices.

Paragraph 50. A method according to any of Paragraphs 34 to 49, wherein the determination is made by the infrastructure equipment based on a Radio Resource Control, RRC, configuration signal transmitted by the infrastructure equipment to the communications device.

Paragraph 51. A method according to Paragraph 50, wherein the RRC configuration signal is transmitted specifically to the communications device by the infrastructure equipment. Paragraph 52. A method according to Paragraph 50 or Paragraph 51, wherein the RRC configuration signal is broadcast by the infrastructure equipment and is receivable by the communications device and one or more other communications devices.

Paragraph 53. A method according to any of Paragraphs 50 to 52, wherein the RRC configuration signal indicates whether or not the communications device can transmit the second portion of the data in the overlap region of the first set of communications resources as a default configuration.

Paragraph 54. A method according to Paragraph 53, wherein the RRC configuration signal indicates that the default configuration may be overridden by a later indication dynamically transmitted by the infrastructure equipment to the communications device.

Paragraph 55. A method according to any of Paragraphs 34 to 54, wherein the determination is made by the infrastructure equipment based on the duration of the overlap region.

Paragraph 56. A method according to Paragraph 55, wherein if the duration of the overlap region is less than a threshold time, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 57. A method according to Paragraph 55 or Paragraph 56, wherein if the duration of the overlap region is greater than a threshold time, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

Paragraph 58. A method according to any of Paragraphs 34 to 57, wherein the infrastructure equipment is configured to transmit a response to the communications device within a predetermined response period, the response being to a request received by the infrastructure equipment from the communications device to transmit the second portion of the data in the overlap region, wherein the determination is made by the infrastructure equipment in accordance with the response.

Paragraph 59. A method according to Paragraph 58, wherein the predetermined response period starts and ends before the beginning of the idle period of the FFP of the wireless communications network. Paragraph 60. A method according to Paragraph 58 or Paragraph 59, wherein the predetermined response period starts before the beginning of the idle period of the FFP of the wireless communications network and ends after the end of the idle period of the FFP of the wireless communications network but before the end of the COT period of the communications device.

Paragraph 61. A method according to any of Paragraphs 58 to 60, wherein the predetermined response period starts after the end of the idle period of the FFP of the wireless communications network and ends before the end of the COT period of the communications device.

Paragraph 62. A method according to any of Paragraphs 58 to 61, wherein if the response is received within the predetermined response period, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

Paragraph 63. A method according to any of Paragraphs 58 to 62, wherein if the response is received within the predetermined response period, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 64. A method according to any of Paragraphs 58 to 63, wherein if the response is not received within the predetermined response period, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

Paragraph 65. A method according to any of Paragraphs 58 to 64, wherein if the response is not received within the predetermined response period, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 66. An infrastructure equipment forming part of a wireless communications network configured to transmit signals to and/or to receive signals from a communications device within communications resources of an unlicensed channel of a wireless access interface, the infrastructure equipment comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface provided by the infrastructure equipment, and controller circuitry configured in combination with the transceiver circuitry to receive a first portion of data from the communications device in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, to determine whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the infrastructure equipment stops reception of the data, and, in accordance with the determination, either to receive the second portion of the data from the communications device in the overlap region, or to determine that the communications device has refrained from restarting transmission of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

Paragraph 67. Circuitry for an infrastructure equipment forming part of a wireless communications network configured to transmit signals to and/or to receive signals from a communications device within communications resources of an unlicensed channel of a wireless access interface, the circuitry comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface provided by the circuitry, and controller circuitry configured in combination with the transceiver circuitry to receive a first portion of data from the communications device in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, to determine whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the infrastructure equipment stops reception of the data, and, in accordance with the determination, either to receive the second portion of the data from the communications device in the overlap region, or to determine that the communications device has refrained from restarting transmission of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network. It will be appreciated that the above description for clarity has described embodiments with reference to different functional units, circuitry and/or processors. However, it will be apparent that any suitable distribution of functionality between different functional units, circuitry and/or processors may be used without detracting from the embodiments. Described embodiments may be implemented in any suitable form including hardware, software, firmware or any combination of these. Described embodiments may optionally be implemented at least partly as computer software running on one or more data processors and/or digital signal processors. The elements and components of any embodiment may be physically, functionally and logically implemented in any suitable way. Indeed the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units. As such, the disclosed embodiments may be implemented in a single unit or may be physically and functionally distributed between different units, circuitry and/or processors.

Although the present disclosure has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognise that various features of the described embodiments may be combined in any manner suitable to implement the technique.

References

[1] Holma H. and Toskala A, “LTE for UMTS OFDMA and SC-FDMA based radio access”, John Wiley and Sons, 2009.

[2] TR 38.913, “Study on Scenarios and Requirements for Next Generation Access Technologies (Release 14)”, third Generation Partnership Project, vl4.3.0.

[3] RP- 190726, “Physical layer enhancements for NR ultra-reliable and low latency communication (URFFC)”, Huawei, HiSilicon, RAN#83.

[4] RP-201310, “Revised WID: Enhanced Industrial Internet of Things (IoT) and ultra-reliable and low latency communication (URFFC) support for NR,” Nokia, Nokia Shanghai Bell, RAN#88e. [5] RP-191575, “NR-based Access to Unlicensed Spectrum,” Qualcomm, RAN#84.

[6] European patent application number EP20187799.0.

[7] Rl-2008161, “Enhancements for unlicensed band URFFC/IIoT,” Samsung, RANl#103e.

[8] Rl-2008568, “UF enhancements for IIoT/URFFC in unlicensed controlled environment,” Nokia, Nokia Shanghai Bell, RANl#103e.

Claims

CLAIMS What is claimed is:

1. A method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface, the method comprising transmitting a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data, and, in accordance with the determination, either transmitting the second portion of the data in the overlap region, or refraining from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

2. A method according to Claim 1, wherein the determination is made by the communications device if the communications device determines that it is not able to transmit the second portion of the data during the idle period of the FFP of the wireless communications network.

3. A method according to Claim 1, wherein the determination is made by the communications device based on an indication received from the wireless communications network.

4. A method according to Claim 3, wherein, based on receiving the indication, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

5. A method according to Claim 3, wherein, based on receiving the indication, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

6. A method according to Claim 3, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

7. A method according to Claim 3, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

8. A method according to Claim 3, wherein the indication is received from the wireless communications network within a silence period of the COT period of the communications device.

9. A method according to any of Claims 6 to 8, wherein the silence period is located at the start of the overlap region and beginning at the end of the idle period of the FFP of the wireless communications network.

10. A method according to any of Claims 6 to 8, wherein the silence period is located outside of the overlap region and ending before the beginning of the idle period of the FFP of the wireless communications network.

11. A method according to Claim 3, wherein the indication is received within a resource grant for a signal to be transmitted by the communications device within the first set of communications resources.

12. A method according to Claim 11, wherein the indication further indicates whether or not the communications device can transmit the first portion of the data in a region of the first set of communications resources that overlaps with the idle period of the FFP of the wireless communications network.

13. A method according to Claim 3, wherein the indication is received within a downlink feedback information, DFI, signal, the DFI comprising feedback from the wireless communications network for signals transmitted by the communications device to the wireless communications network.

14. A method according to Claim 3, wherein the indication comprises whether or not a DFI signal is received by the communications device.

15. A method according to Claim 3, wherein the indication is received within downlink control information, DCI, the DCI being common for the communications device and one or more other communications devices.

16. A method according to Claim 1, wherein the determination is made by the communications device based on a Radio Resource Control, RRC, configuration signal received from the wireless communications network.

17. A method according to Claim 16, wherein the RRC configuration signal is transmitted specifically to the communications device by the wireless communications network.

18. A method according to Claim 16, wherein the RRC configuration signal is broadcast by the wireless communications network and is receivable by the communications device and one or more other communications devices.

19. A method according to Claim 16, wherein the RRC configuration signal indicates whether or not the communications device can transmit the second portion of the data in the overlap region of the first set of communications resources as a default configuration.

20. A method according to Claim 19, wherein the RRC configuration signal indicates that the default configuration may be overridden by a later indication dynamically received by the communications device from the wireless communications network.

21. A method according to Claim 1, wherein the determination is made by the communications device based on the duration of the overlap region.

22. A method according to Claim 21, wherein if the duration of the overlap region is less than a threshold time, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

23. A method according to Claim 21, wherein if the duration of the overlap region is greater than a threshold time, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

24. A method according to Claim 1, wherein the determination is made by the communications device based on a response from the wireless communications network monitored for by the communications device within a predetermined response period, the response being to a request transmitted by the communications device to the wireless communications network to transmit the second portion of the data in the overlap region.

25. A method according to Claim 24, wherein the predetermined response period starts and ends before the beginning of the idle period of the FFP of the wireless communications network.

26. A method according to Claim 24, wherein the predetermined response period starts before the beginning of the idle period of the FFP of the wireless communications network and ends after the end of the idle period of the FFP of the wireless communications network but before the end of the COT period of the communications device.

27. A method according to Claim 24, wherein the predetermined response period starts after the end of the idle period of the FFP of the wireless communications network and ends before the end of the COT period of the communications device.

28. A method according to Claim 24, wherein if the response is received within the predetermined response period, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

29. A method according to Claim 24, wherein if the response is received within the predetermined response period, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

30. A method according to Claim 24, wherein if the response is not received within the predetermined response period, the communications device determines that it can transmit the second portion of the data, and transmits the second portion of the data in the overlap region.

31. A method according to Claim 24, wherein if the response is not received within the predetermined response period, the communications device determines that it cannot transmit the second portion of the data, and refrains from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

32. A communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface, the communications device comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface, and controller circuitry configured in combination with the transceiver circuitry to transmit a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data, and, in accordance with the determination, either to transmit the second portion of the data in the overlap region, or to refrain from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

33. Circuitry for a communications device configured to transmit signals to and/or to receive signals from a wireless communications network within communications resources of an unlicensed channel of a wireless access interface, the circuitry comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface, and controller circuitry configured in combination with the transceiver circuitry to transmit a first portion of data in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the communications device stops transmission of the data, and, in accordance with the determination, either to transmit the second portion of the data in the overlap region, or to refrain from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

34. A method of operating an infrastructure equipment forming part of a wireless communications network configured to transmit signals to and/or to receive signals from a communications device within communications resources of an unlicensed channel of a wireless access interface, the method comprising receiving a first portion of data from the communications device in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications, determining whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the infrastructure equipment stops reception of the data, and, in accordance with the determination, either receiving the second portion of the data from the communications device in the overlap region, or determining that the communications device has refrained from restarting transmission of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

35. A method according to Claim 34, wherein the infrastructure equipment stops the reception of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network only if the infrastructure equipment did not schedule any signals to be transmitted by the communications device in the overlap region.

36. A method according to Claim 34, wherein the determination is made by the infrastructure equipment if the infrastructure equipment determines that the communications device is not able to transmit the second portion of the data during the idle period of the FFP of the wireless communications network.

37. A method according to Claim 34, wherein the determination is made by the infrastructure equipment based on an indication transmitted to the communications device by the infrastructure equipment.

38. A method according to Claim 37, wherein, based on transmitting the indication, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

39. A method according to Claim 37, wherein, based on receiving the indication, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

40. A method according to Claim 37, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

41. A method according to Claim 37, wherein, based on not receiving the indication within a silence period of the COT period of the communications device, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

42. A method according to Claim 37, wherein the indication is transmitted to the communications device within a silence period of the COT period of the communications device.

43. A method according to any of Claims 40 to 42, wherein the silence period is located at the start of the overlap region and beginning at the end of the idle period of the FFP of the wireless communications network.

44. A method according to any of Claims 40 to 42, wherein the silence period is located outside of the overlap region and ending before the beginning of the idle period of the FFP of the wireless communications network.

45. A method according to Claim 37, wherein the indication is transmitted within a resource grant for a signal to be transmitted by the communications device within the first set of communications resources.

46. A method according to Claim 45, wherein the indication further indicates whether or not the communications device can transmit the first portion of the data in a region of the first set of communications resources that overlaps with the idle period of the FFP of the wireless communications network.

47. A method according to Claim 37, wherein the indication is transmitted within a downlink feedback information, DFI, signal, the DFI comprising feedback from the infrastructure equipment for signals received by the infrastructure equipment from the communications device.

48. A method according to Claim 37, wherein the indication comprises whether or not a DFI signal is received by the communications device.

49. A method according to Claim 37, wherein the indication is transmitted within downlink control information, DCI, the DCI being common for the communications device and one or more other communications devices.

50. A method according to Claim 34, wherein the determination is made by the infrastructure equipment based on a Radio Resource Control, RRC, configuration signal transmitted by the infrastructure equipment to the communications device.

51. A method according to Claim 50, wherein the RRC configuration signal is transmitted specifically to the communications device by the infrastructure equipment.

52. A method according to Claim 50, wherein the RRC configuration signal is broadcast by the infrastructure equipment and is receivable by the communications device and one or more other communications devices.

53. A method according to Claim 50, wherein the RRC configuration signal indicates whether or not the communications device can transmit the second portion of the data in the overlap region of the first set of communications resources as a default configuration.

54. A method according to Claim 53, wherein the RRC configuration signal indicates that the default configuration may be overridden by a later indication dynamically transmitted by the infrastructure equipment to the communications device.

55. A method according to Claim 34, wherein the determination is made by the infrastructure equipment based on the duration of the overlap region.

56. A method according to Claim 55, wherein if the duration of the overlap region is less than a threshold time, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

57. A method according to Claim 55, wherein if the duration of the overlap region is greater than a threshold time, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

58. A method according to Claim 34, wherein the infrastructure equipment is configured to transmit a response to the communications device within a predetermined response period, the response being to a request received by the infrastructure equipment from the communications device to transmit the second portion of the data in the overlap region, wherein the determination is made by the infrastructure equipment in accordance with the response.

59. A method according to Claim 58, wherein the predetermined response period starts and ends before the beginning of the idle period of the FFP of the wireless communications network.

60. A method according to Claim 58, wherein the predetermined response period starts before the beginning of the idle period of the FFP of the wireless communications network and ends after the end of the idle period of the FFP of the wireless communications network but before the end of the COT period of the communications device.

61. A method according to Claim 58, wherein the predetermined response period starts after the end of the idle period of the FFP of the wireless communications network and ends before the end of the COT period of the communications device.

62. A method according to Claim 58, wherein if the response is received within the predetermined response period, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

63. A method according to Claim 58, wherein if the response is received within the predetermined response period, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

64. A method according to Claim 58, wherein if the response is not received within the predetermined response period, the infrastructure equipment determines that it will receive the second portion of the data from the communications device, and receives the second portion of the data in the overlap region.

65. A method according to Claim 58, wherein if the response is not received within the predetermined response period, the infrastructure equipment determines that it will not receive the second portion of the data from the communications device, and determines that the communications device has refrained from restarting the transmission of the data in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

66. An infrastructure equipment forming part of a wireless communications network configured to transmit signals to and/or to receive signals from a communications device within communications resources of an unlicensed channel of a wireless access interface, the infrastructure equipment comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface provided by the infrastructure equipment, and controller circuitry configured in combination with the transceiver circuitry to receive a first portion of data from the communications device in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, to determine whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the infrastructure equipment stops reception of the data, and, in accordance with the determination, either to receive the second portion of the data from the communications device in the overlap region, or to determine that the communications device has refrained from restarting transmission of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.

67. Circuitry for an infrastructure equipment forming part of a wireless communications network configured to transmit signals to and/or to receive signals from a communications device within communications resources of an unlicensed channel of a wireless access interface, the circuitry comprising transceiver circuitry configured to transmit signals and receive signals via a wireless access interface provided by the circuitry, and controller circuitry configured in combination with the transceiver circuitry to receive a first portion of data from the communications device in a first set of the communications resources in accordance with a fixed frame period, FFP, wherein the first set of the communications resources is a channel occupancy time, COT, period, and wherein the FFP overlaps in time with an FFP of the wireless communications network, to determine whether the communications device can transmit a second portion of the data in an overlap region of the first set of communications resources, wherein the overlap region is a portion of the COT period that overlaps in time with a COT period of the wireless communications network used by the wireless communications network for transmitting signals to the communications device in accordance with the FFP of the wireless communications network, and wherein the overlap region and the COT period of the wireless communications network each begin at the end of an idle period of the FFP of the wireless communications network before which the infrastructure equipment stops reception of the data, and, in accordance with the determination, either to receive the second portion of the data from the communications device in the overlap region, or to determine that the communications device has refrained from restarting transmission of the data from the communications device in the first set of communications resources after the end of the idle period of the FFP of the wireless communications network.