Patent Publication Number: US-2022225303-A1

Title: Communications device, infrastructure equipment and methods

Description:
BACKGROUND 
     Field 
     The present disclosure relates to communications devices, infrastructure equipment and methods for the reception of data by a communications device in a wireless communications network. The present application claims the Paris convention priority of EP19172640.5 filed 3 May 2019 the contents of which are incorporated herein 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. 
     Third and fourth generation mobile telecommunication systems, such as those based on the 3GPP defined UMTS and Long Term Evolution (LTE) architecture, are able to support more sophisticated 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, may be expected to increase ever more rapidly. 
     Future wireless communications networks will be expected to support communications routinely and efficiently with a wider range of devices associated with a wider range of data traffic profiles and types than current 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. 
     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) system/new radio access technology (RAT) systems [1], 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. 
     An example of such 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. URLLC type services therefore represent a challenging example for both LTE type communications systems and 5G/NR communications systems. 
     The increasing use of different types of communications devices associated with different traffic profiles gives rise to new challenges for efficiently handling communications in wireless telecommunications systems that need to be addressed. 
     SUMMARY 
     The present disclosure can help address or mitigate at least some of the issues discussed above. 
     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: 
         FIG. 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; 
         FIG. 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; 
         FIG. 3  is a schematic block diagram of an example infrastructure equipment and communications device which may be configured in accordance with example embodiments; 
         FIG. 4  illustrates a reception of downlink data in accordance with conventional techniques; 
         FIG. 5  illustrates an example downlink transmission of data in accordance with embodiments of the present disclosure; 
         FIG. 6  illustrates possible durations of allocated downlink shared channel resources in accordance with embodiments of the present technique; 
         FIG. 7  illustrates reception of downlink data in accordance with embodiments of the present disclosure; 
         FIG. 8  illustrates reception of downlink data in accordance with embodiments of the present disclosure; 
         FIG. 9  illustrates an example of downlink communications resources allocated by means of a downlink control channel transmission in accordance with embodiments of the present technique; 
         FIG. 10  illustrates an allocation of uplink communications resources in accordance with embodiments of the present technique; 
         FIG. 11  shows an example of a scheduled downlink shared channel transmission in accordance with embodiments of the present technique; 
         FIG. 12  illustrates a flowchart for a process of receiving data by a communications device from an infrastructure equipment in accordance with embodiments of the present technique; and 
         FIG. 13  illustrates a flowchart for a process of transmitting data to a communications device by an infrastructure equipment in accordance with embodiments of the present technique. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Long Term Evolution Advanced Radio Access Technology (4G) 
       FIG. 1  provides a schematic diagram illustrating some basic functionality of a mobile telecommunications network/system  100  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  FIG. 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 [2]. 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  100  includes a plurality of base stations  101  connected to a core network part  102 . Each base station provides a coverage area  103  (e.g. a cell) within which data can be communicated to and from communications devices  104 . Data is transmitted from the base stations  101  to the communications devices  104  within their respective coverage areas  103  via a radio downlink. Data is transmitted from the communications devices  104  to the base stations  101  via a radio uplink. The core network part  102  routes data to and from the communications devices  104  via the respective base stations  101  and provides functions such as authentication, mobility management, charging and so on. Communications devices may also be referred to as mobile stations, user equipment (UE), user terminals, mobile radios, terminal devices, and so forth. Base stations, which are an example of network infrastructure equipment/network access nodes, may also be referred to as transceiver stations/nodeBs/e-nodeBs, 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, example embodiments of the disclosure may be equally implemented in different generations of wireless telecommunications systems such as 5G or new radio as explained below, 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) 
       FIG. 2  is a schematic diagram illustrating a network architecture for a new RAT wireless communications network/system  200  based on previously proposed approaches which may also be adapted to provide functionality in accordance with embodiments of the disclosure described herein. The new RAT network  200  represented in  FIG. 2  comprises a first communication cell  201  and a second communication cell  202 . Each communication cell  201 ,  202 , comprises a controlling node (centralised unit)  221 ,  222  in communication with a core network component  210  over a respective wired or wireless link  251 ,  252 . The respective controlling nodes  221 ,  222  are also each in communication with a plurality of distributed units (radio access nodes/remote transmission and reception points (TRPs))  211 ,  212  in their respective cells. Again, these communications may be over respective wired or wireless links. The distributed units  211 ,  212  are responsible for providing the radio access interface for communications devices connected to the network. Each distributed unit  211 ,  212  has a coverage area (radio access footprint)  241 ,  242  where the sum of the coverage areas of the distributed units under the control of a controlling node together define the coverage of the respective communication cells  201 ,  202 . Each distributed unit  211 ,  212  includes transceiver circuitry for transmission and reception of wireless signals and processor circuitry configured to control the respective distributed units  211 ,  212 . 
     In terms of broad top-level functionality, the core network component  210  of the new RAT communications network represented in  FIG. 2  may be broadly considered to correspond with the core network  102  represented in  FIG. 1 , and the respective controlling nodes  221 ,  222  and their associated distributed units/TRPs  211 ,  212  may be broadly considered to provide functionality corresponding to the base stations  101  of  FIG. 1 . The term network infrastructure equipment/access node may be used to encompass these elements and more conventional base station type elements of wireless communications 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/centralised unit and/or the distributed units/TRPs. 
     A communications device or UE  260  is represented in  FIG. 2  within the coverage area of the first communication cell  201 . This communications device  260  may thus exchange signalling with the first controlling node  221  in the first communication cell via one of the distributed units  211  associated with the first communication cell  201 . In some cases communications for a given communications device are routed through only one of the distributed units, but it will be appreciated in some other implementations communications associated with a given communications device may be routed through more than one distributed unit, for example in a soft handover scenario and other scenarios. 
     In the example of  FIG. 2 , two communication cells  201 ,  202  and one communications device  260  are shown for simplicity, but it will of course be appreciated that in practice the system may comprise a larger number of communication cells (each supported by a respective controlling node and plurality of distributed units) serving a larger number of communications devices. 
     It will further be appreciated that  FIG. 2  represents merely one example of a proposed architecture for a new RAT communications 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 communications systems having different architectures. 
     Thus example 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  FIGS. 1 and 2 . It will thus be appreciated the specific wireless communications architecture in any given implementation is not of primary significance to the principles described herein. In this regard, example 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  101  as shown in  FIG. 1  which is adapted to provide functionality in accordance with the principles described herein, and in other examples the network infrastructure equipment/access node may comprise a control unit/controlling node  221 ,  222  and/or a TRP  211 ,  212  of the kind shown in  FIG. 2  which is adapted to provide functionality in accordance with the principles described herein. 
     A more detailed illustration of a UE  270  and an example network infrastructure equipment  272 , which may be thought of as a gNB  101  or a combination of a controlling node  221  and TRP  211 , is presented in  FIG. 3 . As shown in  FIG. 3 , the UE  270  is shown to transmit uplink data to the infrastructure equipment  272  via resources of a wireless access interface as illustrated generally by an arrow  274 . The UE  270  may similarly be configured to receive downlink data transmitted by the infrastructure equipment  272  via resources of the wireless access interface (not shown). As with  FIGS. 1 and 2 , the infrastructure equipment  272  is connected to a core network  276  via an interface  278  to a controller  280  of the infrastructure equipment  272 . The infrastructure equipment  272  includes a receiver  282  connected to an antenna  284  and a transmitter  286  connected to the antenna  284 . Correspondingly, the UE  270  includes a controller  290  connected to a receiver  292  which receives signals from an antenna  294  and a transmitter  296  also connected to the antenna  294 . 
     The controller  280  is configured to control the infrastructure equipment  272  and may comprise processor circuitry which may in turn comprise various sub-units/sub-circuits for providing functionality as explained further herein. These sub-units may be implemented as discrete hardware elements or as appropriately configured functions of the processor circuitry. Thus the controller  280  may comprise circuitry which is suitably configured/programmed to provide the desired functionality using conventional programming/configuration techniques for equipment in wireless telecommunications systems. The transmitter  286  and the receiver  282  may comprise signal processing and radio frequency filters, amplifiers and circuitry in accordance with conventional arrangements. The transmitter  286 , the receiver  282  and the controller  280  are schematically shown in  FIG. 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  272  will in general comprise various other elements associated with its operating functionality. 
     Correspondingly, the controller  290  of the UE  270  is configured to control the transmitter  296  and the receiver  292  and may comprise processor circuitry which may in turn comprise various sub-units/sub-circuits for providing functionality as explained further herein. These sub-units may be implemented as discrete hardware elements or as appropriately configured functions of the processor circuitry. Thus the controller  290  may comprise circuitry which is suitably configured/programmed to provide the desired functionality using conventional programming/configuration techniques for equipment in wireless telecommunications systems. Likewise, the transmitter  296  and the receiver  292  may comprise signal processing and radio frequency filters, amplifiers and circuitry in accordance with conventional arrangements. The transmitter  296 , receiver  292  and controller  290  are schematically shown in  FIG. 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 communications device  270  will in general comprise various other elements associated with its operating functionality, for example a power source, user interface, and so forth, but these are not shown in  FIG. 3  in the interests of simplicity. 
     The controllers  280 ,  290  may be 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. 
     5G, URLLC and Industrial Internet of Things 
     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 &amp; Low Latency Communications (URLLC) services are for a reliability of 1-10 −5  (99.999%) or higher for one transmission of a 32 byte packet with a user plane latency of 1 ms [3]. In some scenarios, there may be a requirement for a reliability of 1-10 −6  (99.9999%) or higher with either 0.5 ms or 1 ms of user plane latency. 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. 
     Industrial automation, energy power distribution and intelligent transport systems are examples of new use cases for Industrial Internet of Things (IIoT). In an example of industrial automation, the system may involve different distributed components working together. These components may include sensors, virtualized hardware controllers and autonomous robots, which may be capable of initiating actions or reacting to critical events occurring within a factory and communicating over a local area network. 
     The UEs in the network may therefore be expected to handle a mixture of different traffic, for example, associated with different applications and potentially different quality of service requirements (such as maximum latency, reliability, packet sizes, throughput). Some messages for transmission may be time sensitive and be associated with strict deadlines and the communications network may therefore be required to provide time sensitive networking (TSN) [6]. 
     URLLC services are required in order to meet the requirements for IIoT, which require high availability, high reliability, low latency, and in some cases, high-accuracy positioning [1]. Some IIoT services may be implemented by using a mixture of eMBB and URLLC techniques, where some data is transmitted by eMBB and other data is transmitted by URLLC. 
     Downlink Control Information 
     In 5G/NR, communications resources for both uplink and downlink communications are allocated by the infrastructure equipment, and may be signalled to the communications device in downlink control information (DCI), transmitted using a physical downlink control channel (PDCCH). 
     Each communications device may be configured with a specific search space within which the PDCCH may exist, the search space defining communications resources (and, optionally, other parameters) with which DCI allocating communications resources to that communications device may be transmitted. 
     A communications device may be configured with a PDCCH search space for each of a plurality of services. For example, communications resources allocated for the transmission or reception of URLLC data may be allocated by means of DCI transmitted in accordance with one search space, while communications resources allocated for the transmission or reception of eMBB data may be allocated by means of DCI transmitted in accordance with a different search space. The multiple PDCCH search spaces may be mutually exclusive, such that any PDCCH transmission which is in accordance with one PDCCH search space is necessarily not in accordance with a different PDCCH search space configured for the same communications device. 
     The PDCCH search space(s) may be configured for the communications device by means of RRC signalling. 
     Even within the constraints of a configured search space, there may be different parameters according to which DCI may be transmitted to a communications device, and there is no specific a priori indication to the communications device indicating if, or how, any DCI will be transmitted to the communications device. 
     Accordingly, it is necessary for a communications device to ‘blind decode’ multiple PDCCH ‘candidates’ within the search space, in order to attempt to determine if any DCI has been transmitted to it. Because of the different permitted parameters for transmitting the DCI, the communications device may have to attempt multiple blind decode attempts for given communications resources on which the DCI may (or may not) be transmitted. 
     Communications Resources for Downlink Data 
     Downlink data transmitted to a communications device may be transmitted using a Physical Downlink Shared Channel (PDSCH). The PDSCH can be dynamically scheduled by the infrastructure equipment in a Downlink (DL) Grant, i.e. scheduling information contained in a DCI. The DCI may be formatted in accordance with one of a plurality of predetermined (e.g. standardised) formats, such as DCI Format 1_0 and DCI Format 1_1. 
     The DL Grant comprises Frequency Domain Resource Assignment (FDRA) and Time Domain Resource Assignment (TDRA) fields, which indicate the frequency and time resources of the PDSCH respectively. The FDRA indicates a number and location of physical resource blocks (PRBs) occupied by the PDSCH. 
     The TDRA field may comprise an index to a row of a TDRA Table, where each entry/row in this table specifies a position of downlink measurement reference symbols (DMRS), a mapping type for the PDSCH (which may be a Type A or Type B mapping), a slot gap parameter K 0 , a start symbol offset S and a duration of the PDSCH resources L. 
       FIG. 4  illustrates a reception of downlink data in accordance with conventional techniques.  FIG. 4  illustrates an example of a use of the K 0 , S and L parameters for a PDSCH. 
       FIGS. 4  shows communications resources  402  of a downlink of a wireless access interface of a wireless communications network. The communications resources are divided into timeslots n, n+1, n+2, each of which is further subdivided into 14 orthogonal frequency division multiplexing (OFDM) symbol periods  404 . 
     A DL grant is transmitted within a PDCCH transmission  406  from time t 0  to time t 1  within timeslot n. The DL Grant comprises a TDRA index which points to an entry in the TDRA Table which indicates parameters K 0 =2, S=7 and L=7. Since the DL Grant is in Slot n, the allocated PDSCH resources therefore start in Slot n+K 0 , i.e. Slot n+2. The symbol offset from the slot boundary of Slot n+2 is indicated by the parameter S, which in this case is 7 symbols from the slot boundary. Accordingly, the start time of the PDSCH is at time t 5  (7 symbols from the start of timeslot n+2). The duration of the PDSCH is L=7 symbols. Hence, the TDRA parameters indicate a PDSCH transmission between time t 5  and t 6  as shown in  FIG. 4 . The entries in the TDRA table may be semi-statically configured by radio resource configuration (RRC) and the size of the table may be up to 16 entries. 
     Until a DCI has been successfully decoded, it is not possible for the communications device to determine which, if any, communications resources have been allocated to it for the uplink or downlink transmission of data. In the case of downlink transmissions, if the allocated communications resources may coincide in time with the blind decoding of the DCI, it is necessary for the communications device to pre-emptively receive and buffer signals received on downlink communications resources which may be allocated for the downlink transmission of data. These buffered signals may subsequently be processed (i.e. decoded) only if DCI is successfully decoded indicating that downlink data is (has been) transmitted using these downlink communications resources. 
     In the example of  FIG. 4 , a downlink PDCCH transmission  406  occurs from time t 0  to time t 1 . A communications device, such as the communications device  270  described above, controls its receiver  292  to receive the signals of the PDCCH, in accordance with a pre-configured PDCCH search space. 
     During the time period N PDCCH  from time t 1  to time t 2 , the communications device  270  performs blind decoding of the PDCCH received signals. The PDCCH transmission  406  may indicate that downlink communications resources starting at, or after, time t 1  are allocated for the downlink transmission of data to the communications device  270 . Accordingly, during the time period from t 1  to t 2 , the communications device  270  may configure its receiver to receive downlink signals of a PDSCH on which the downlink data may be being transmitted. 
     In the example of  FIG. 4 , as a result of the blind decoding of the PDCCH signals received from time t 0  to time t 1 , the communications device  270  determines that PDCCH transmission  406  comprises DCI. Furthermore, the communications device  270  determines that the DCI indicates that downlink communications resources  408  of the PDSCH, from time t 5  to time t 6 , are allocated for the downlink transmission of data to the communications device  270 . Accordingly, the communications device  270  may control its receiver  292  to receive signals of the PDSCH from time t 5  to time t 6 . These received PDSCH signals may be decoded, and the communications device  270  may accordingly receive the data transmitted by the infrastructure equipment. 
     It has been appreciated that requiring the communications device  270  to enable its receiver during the time period t 1  to t 2  (i.e. while blind decoding of the PDCCH signal is being carried out) is an inefficient use of power, especially in cases (as in  FIG. 4 ) where no PDSCH transmission is scheduled for the communications device  270  during that time. 
     To address this, one proposal within the context of ongoing work related to power-saving in 5G/NR [7] is that a DL grant may only allocate downlink communications resources which start in a slot occurring after the slot in which the DL grant is transmitted. In other words, K 0  may be constrained to be no less than 1. Such scheduling is referred to as ‘cross-slot scheduling’. In accordance with this proposal, the communications device  270  would not be required to enable its receiver between the end of the communications resources on which the DCI may be transmitted, and the beginning of the subsequent slot. 
     As described above, one of the targeted services for 5G is Ultra Reliable Low Latency Communications (URLLC) where it is required that a data packet at layer  2  is transmitted with a latency that is less than 1 ms or 0.5 ms with reliability of 99.999% to 99.9999%. Since the cross-slot scheduling power saving scheme introduces additional latency, and considering that a slot duration may be 1 ms for 15 kHz Subcarrier Spacing, it is not suitable for URLLC transmissions. Hence, a different power saving scheme is required for URLLC. 
     Embodiments of the present technique provide a method for receiving data by a communications device from a wireless communications network, the method comprising: receiving a downlink control message transmitted in first downlink communications resources of a wireless access interface provided by the wireless communications network, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, decoding the downlink control message to identify the second downlink communications resources for receiving the downlink data, and receiving the downlink data from the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded. 
     In accordance with embodiments of the present technique, downlink data is constrained to be transmitted within a certain PDSCH time window. In particular, the PDSCH time window may be characterised by a PDSCH time window end which may be referred to as a pre-configured end time, which occurs prior to the end of a time period during which the communications device  270  performs decoding of a received downlink control message, which may be transmitted using, for example, PDCCH signals. Accordingly, the communications device  270  is able to disable part or all of its receiver  292  after the end of the time window, thus reducing power consumption compared with conventional techniques, which may require the communications device to continue to receive signals until the downlink control message has been decoded. In addition, embodiments of the present technique can ensure that latency requirements associated with the data can be satisfied. 
       FIG. 5  illustrates an example downlink transmission of data in accordance with embodiments of the present disclosure. 
     In the example shown in  FIG. 5 , in accordance with the preconfigured PDCCH search space, the communications device  270  enables its receiver for receiving PDCCH signals from time t 0  to time t 1 . In the example of  FIG. 5 , the PDSCH time window end is time t 2 . That is, a transmission of downlink data on communications resources which are indicated by a DCI transmitted using the PDCCH from time t 0  to time t 1 , is constrained to be completed by time t 2 . 
     Accordingly, the communications device  270  enables its receiver  292  to receive signals of the PDSCH until at least time t 2 , and may disable its receiver  292  at time t 2 , even if it has not yet completed decoding of the PDCCH signals received from time t 0  to time t 1 . 
     In the example of  FIG. 5 , the PDSCH time window end or time t 2  (i.e. the time after which downlink data transmission cannot occur) is characterised by a parameter N END , which specifies a duration between the start of the PDCCH transmission (or potential PDCCH transmission) and time t 2 . However, the present disclosure is not so limited, and the PDSCH time window end may be determined in other ways, as will be described below. 
     In the example of  FIG. 5 , downlink data is scheduled to be transmitted using communications resources  504 , and an indication of the communications resources  504  is transmitted within DCI transmitted using PDCCH transmission  502 . 
     As described above, the communications device  270  may require N PDCCH  OFDM symbols (i.e. until time t 3 ) in order to decode the PDCCH transmission  502 . It will be appreciated that since time t 2  occurs prior to time t 3 , then in accordance with embodiments of the present technique, the power consumption of the communications device  270  may be reduced, compared with conventional techniques, since the communications device  270  is not required to enable its receiver  292  to receive signals between time t 2  and time t 3 . 
     Determination of PDSCH Time Window End 
     According to embodiments of the present technique, for each possible PDCCH instance (such as, in accordance with the preconfigured associated PDCCH search space), the communications device  270  determines the PDSCH time window end. Techniques by which the PDSCH time window end may be determined, in accordance with embodiment of the present technique, will now be presented. 
     TDRA Table Configuration 
     In some embodiments, the infrastructure equipment  292  configures the communications device  270  with a TDRA table, that is, a correspondence between TDRA indices and parameters defining the start time and duration of allocated PDSCH resources. The parameters may define the start time and duration relative to a slot in which DCI comprising the TDRA index is transmitted, as described above. 
     In some such embodiments, the PDSCH time window end is determined by calculating the latest end time for allocated PDSCH resources which can be indicated in accordance with any of the rows/indices of the TDRA table. 
     An example of a TDRA table is shown in Table 1, in which the PDSCH Mapping Type and DMRS position parameters are omitted for conciseness. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Example TDRA entries for PDSCH 
               
            
           
           
               
               
               
               
               
            
               
                   
                 TDRA Index 
                 K 0   
                 S 
                 L 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 0 
                 0 
                 0 
                 2 
               
               
                   
                 1 
                 0 
                 0 
                 4 
               
               
                   
                 2 
                 0 
                 2 
                 2 
               
               
                   
                 3 
                 0 
                 2 
                 3 
               
               
                   
                   
               
            
           
         
       
     
       FIG. 6  illustrates possible PDSCH durations in accordance with embodiments of the present technique. Specifically,  FIG. 6  illustrates a potential PDCCH transmission  602  from time t 0  to time t 1  in accordance with a PDCCH search space. In addition, by means of arrows  604   a ,  604   b ,  604   c ,  604   d ,  FIG. 6  also shows durations of PDSCH transmissions scheduled by means of the inclusion of an indication of the TDRA indices  0  to  3  respectively within DCI transmitted using the PDCCH transmission  602 . (The relative vertical positioning of the arrows  604  has no significance). 
     In the example of  FIG. 6 , the communications device  270  first determines that DCI may be transmitted using a PDCCH transmission  602  in accordance with a PDCCH search space with which the communications device  270  is configured. 
     The communications device  270  may then determine that, in accordance with the TDRA table shown in Table 1, the latest possible end time for a PDSCH scheduled by such a DCI is time t 2  (the end time of a PDSCH transmission scheduled using TDRA index  3 ). 
     Accordingly the communications device  270  determines that the PDSCH time window end is at time t 2 . 
     In some embodiments, the TDRA table is configured by the infrastructure equipment  272  in response to an indication by the communications device  270  of a requested N END  value and/or of the communications device&#39;s N PDCCH  value. For example, in some embodiments, the communications device  270  may transmit a PDSCH time window end request indication to the infrastructure equipment  272 , the PDSCH time window end request indication comprising an indication that the N PDCCH  value of the communications device  270  is 5 OFDM symbols. 
     In response, the infrastructure equipment  272  may transmit an indication of a TDRA table in which all indices are associated with a PDSCH time window end occurring at or prior to 5 OFDM symbols after the end of the associated PDCCH transmission. Preferably, the infrastructure equipment  272  transmits an indication of a TDRA table in which all indices are associated with a PDSCH time window end occurring prior to N PDCCH  OFDM symbols after the end of the associated PDCCH transmission. 
     Explicit Configuration of N END    
     In some embodiments, the communications device determines the PDSCH time window end based on a predetermined parameter. In some embodiments, an indication of the predetermined parameter may be transmitted by the infrastructure equipment  272 . 
     In some embodiments, the infrastructure equipment  272  may transmit an indication of the N END  value. Accordingly, the communications device  270  determines that the PDSCH time window end occurs N END  OFDM symbols after the start of a corresponding PDCCH transmission. 
     In some embodiments, the communications device may first transmit an indication of a requested value for a parameter (such as a requested N END  parameter value). The request may comprise an indication of the N PDCCH  value of the communications device. 
     In some embodiments, the communications device  270  transmits an indication of its PDCCH processing time N PDCCH  to the infrastructure equipment  272 . The predetermined parameter (such as N END ) may be determined based on the N PDCCH  value indicated to the infrastructure equipment  272 . The predetermined parameter may be determined based on the N PDCCH  value in accordance with a predetermined rule. For example, N END  may be set to be equal to N PDCCH . Thus, in some embodiments, no explicit indication of the predetermined value is transmitted by the infrastructure equipment  272  to the communications device  270 . 
     In some embodiments, the PDCCH processing time N PDCCH  may be implicitly determined based on a maximum number of blind decoding attempts that may be required by the communications device  270  to decode a particular PDCCH transmission. The maximum number of blind decoding attempts may be determined by RRC signalling from the infrastructure equipment  272  or a UE capability of the communications device  270 . The maximum number of blind decoding attempts may further depend on, for example, a number of possible code rates with which the PDCCH transmission is encoded, a number of different communications resources on which the PDCCH transmission may occur, and a number of redundancy options with which the PDCCH transmission may be encoded. 
     An indication of a relationship between the maximum number of blind decodes and the PDCCH processing time N PDCCH  may be transmitted by the communications device  270  to the infrastructure equipment  272 . Accordingly, in some embodiments, the infrastructure equipment  272  may determine the PDCCH processing time N PDCCH  based on the indication of the relationship between the maximum number of blind decodes and the PDCCH processing time N PDCCH . 
     For example, if the maximum number of blind decodes are 22 (respectively 44), the PDCCH processing time N PDCCH  may be 2 (respectively, 4) OFDM symbols. 
     Inapplicable Rows 
     In some embodiments, one or more rows of the configured TDRA table may be incompatible with the predetermined parameter. In some such embodiments, the infrastructure equipment  272  may select for allocation communications resources which are compatible both with the predetermined parameter and which are in accordance with one of the rows of the configured TDRA table. In other words, the infrastructure equipment  272  may refrain from allocating communications resources which are in accordance with (i.e. can be indicated by means of) one or more rows of the configured TDRA table, if the resulting communications resources would be incompatible with the predetermined parameter and thus extend beyond the PDSCH time window end, when determined based on the predetermined parameter. 
     To illustrate an example of such embodiments, Table 2 shows a further example of a configured TDRA table. Table 2 omits for conciseness the PDSCH Mapping Type and DMRS position parameters. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Example TDRA entries for PDSCH 
               
            
           
           
               
               
               
               
               
            
               
                   
                 TDRA Index 
                 K 0   
                 S 
                 L 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 0 
                 0 
                 2 
                 4 
               
               
                   
                 1 
                 0 
                 10 
                 4 
               
               
                   
                 2 
                 1 
                 0 
                 2 
               
               
                   
                 3 
                 2 
                 7 
                 7 
               
               
                   
                   
               
            
           
         
       
     
     In this example, it is clear that some TDRA table entries indicate a PDSCH transmission which occurs significantly after the PDCCH transmission. For example, TDRA index=3 indicates PDSCH resources which start 2 timeslots after the timeslot in which the PDCCH transmission occurs. 
     In this example, the communications device  270  determines that, in accordance with the predetermined parameter, N END =6. That is, the PDSCH time window end occurs 6 OFDM symbols after the start of the corresponding PDCCH transmission. In this example, N PDCCH  for the communications device  270  is 6 OFDM symbols. 
       FIG. 7  shows a PDCCH transmission  702  from time t 1  to time t 2  in accordance with a PDCCH search space, and four possible PDSCH transmissions  704   a - d  whose start time and duration can be indicated by the TDRA table shown in Table 2. 
     Based on the determination that N END =6 and the start time t 1 , the communications device determines that the PDSCH time window end is at time t 4 , being  6  OFDM symbols after time t 1 . 
     Accordingly, the communications device  270  may in some embodiments determine that TDRA indices which may indicate PDSCH communications resources which finish after the PDSCH time window end are inapplicable, i.e. may not be used by the infrastructure equipment  272  for indicating the allocated communications resources for the transmission of downlink data. 
     A corresponding determination may be made by the infrastructure equipment  272 . That is, based on the predetermined parameter, the PDCCH location and the TDRA table configured for the communications device  270 , the infrastructure equipment  272  may determine that one or more TDRA table entries may not be used to indicate an allocation of PDSCH resources for the transmission of downlink data to the communications device  270 . 
     Similarly, the infrastructure equipment  272  and/or communications device  270  may determine that the downlink data must be scheduled for transmission using allocated PDSCH resources which finish at or before the PDSCH time window end and that the allocated PDSCH resources must be selected from those which can be indicated by means of TDRA table indices which are not determined to be inapplicable, as described above. 
     In the example of  FIG. 7 , therefore, the PDSCH resources  704   d , which finish at time t 8  (t 8  &gt;t 4 ) cannot be used for the transmission of the downlink data. Accordingly, the row corresponding to TDRA index  3  is determined to be inapplicable. 
     It should be noted that PDSCH resources  704   a  occur prior to the PDCCH transmission  702 . However, because these resources finish before t 4 , in at least some embodiments, the corresponding index (TDRA index  0 ) is not determined to be inapplicable. 
     Applicable Rows Depend on PDCCH Location 
     In some embodiments, the TDRA entries which are inapplicable may be dependent on the location of the PDCCH. 
       FIG. 8  shows an example of a PDCCH transmission  802  from time t 0  to t 1 , and four possible PDSCH communications resources  804   a - d , in accordance with the TDRA table shown in Table 2. 
     As in the example of  FIG. 7 , the communications device determines that the PDSCH time window end is 6 OFDM symbols after the start time of the PDCCH transmission, i.e. at time t 2 . Accordingly, in the example of  FIG. 8 , only the resources corresponding to TDRA table index  0  can be validly used, since the resources corresponding to each of the other index values finish later than time t 2 . The communications device  270  and/or the infrastructure equipment  272  thus may determine that, for the PDCCH transmission  802 , the TDRA index values 1, 2 and 3 are inapplicable. 
     Replace Inapplicable Rows With Other values 
     In some embodiments, one or more rows of a configured TDRA table which are determined to be inapplicable may be adapted to correspond to parameters indicating allocated resources which comply with the PDSCH time window end. 
     For example, in the example of  FIG. 7  shown above, in which the row corresponding to index  3  is determined to be inapplicable, the parameters associated with index  3  may be changed, as shown in Table 3 below: 
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 Modified TDRA entries for PDSCH 
               
            
           
           
               
               
               
               
               
            
               
                   
                 TDRA Index 
                 K 0   
                 S 
                 L 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 0 
                 0 
                 2 
                 4 
               
               
                   
                 1 
                 0 
                 10 
                 4 
               
               
                   
                 2 
                 1 
                 0 
                 2 
               
               
                   
                 3 
                 0 
                 12 
                 2 
               
               
                   
                   
               
            
           
         
       
     
     Accordingly, for the example in  FIG. 7 , TDRA index  3  may be used to indicate PDSCH resources starting at time t 2  (i.e. the 12 th  OFDM symbol of timeslot n) and finishing at time t 4  (i.e. 4 OFDM symbols later). 
     In some embodiments, where there are two or more TDRA index values which are determined to be inapplicable, these may all be adapted to correspond to the same parameters. That is, each of the inapplicable TDRA index values refer to a same PDSCH communications resource allocation. 
     In some embodiments, the replacement parameters to be associated with non-applicable TDRA row entries may be preconfigured, for example by means of RRC signalling transmitted by the infrastructure equipment  272  to the communications device  270 . 
     Different Power-saving Schemes 
     A communications device may serve URLLC and eMBB traffic, i.e. the PDSCH/PUSCH allocated for the transmission or reception of data can be associated with a low latency requirement (for the transmission of URLLC data within its latency threshold) or may be associated with no, or little, latency restriction (e.g. for the transmission of eMBB data). 
     In some embodiments of the present technique, different power saving schemes are associated with the scheduling of downlink communications resources for the transmission of data having different latency requirements. For example, in some embodiments, resources for eMBB data transmission use the cross-slot scheduling power saving scheme described above. 
     In some embodiments, resources for the transmission of the URLLC data are scheduled using a power saving scheme that defines a PDSCH time window end, as described herein. 
     Where different power saving schemes may be used by the same communications device, the communications device needs to be aware of which scheme is applicable prior to detecting/decoding the PDCCH, since each scheme permits the communications device  270  to disable its receiver  290  at different times. 
     Thus in accordance with embodiments of the present technique, there are provided methods and apparatus for indicating when a particular scheme is to be applied. Accordingly, in some embodiments, the communications device  270  can determine whether a particular power saving scheme is applicable in respect of a PDCCH transmission (or potential PDCCH transmission) and/or which of a plurality of power saving schemes is applicable. 
     For example, in some embodiments, the communications device  270  may determine whether, for a particular PDCCH transmission (or potential PDCCH transmission), PDSCH communications resources will be allocated in accordance with either i) a power saving mode defining a PDSCH time window end as described herein, ii) a cross-slot power saving mode as described above, or iii) no power saving mode. 
     PDCCH Search Space 
     In some embodiments, a PDCCH search space is associated with a particular power-saving scheme (or no power-saving scheme). As described above, a PDCCH search space may characterise communications resources on which the infrastructure equipment  272  may transmit DCI allocating communications resources for the transmission and/or reception of data. Accordingly, the communications device  270  determines that a particularly power-saving scheme is associated with a PDCCH transmission (or potential PDCCH transmission) which is in accordance with a particular PDCCH search space, based on the power saving scheme (if any) associated with the PDCCH search space. 
     Other Options 
     In some embodiments, a power saving mode may be activated by means of a transmission of RRC signalling comprising an indication of the activated power saving mode. 
     In some embodiments, a power saving mode may be activated by means of a transmission of MAC signalling comprising an indication of the activated power saving mode. 
     In some embodiments, a power saving mode may be activated by means of a transmission of DCI comprising an indication of the activated power saving mode. In such embodiments, the DCI may be a group common (GC) DCI. In some embodiments, the DCI comprising the indication of the activated power saving mode comprises an indication of uplink or downlink communications resources. 
     As described above, if a power saving mode is changed or deactivated in respect of a particular PDCCH transmission, then the communications device must be able to determine this prior to the start of the PDCCH transmission. Therefore, preferably, a change or deactivation of a power saving mode is notified in a transmission preceding the first PDCCH transmission to which the new scheme applies. 
     If a power saving mode is newly activated, from a state in which no power saving mode which imposes restrictions on the scheduling of the PDSCH is active, then the communications device need not be able to determine this prior to the start of the PDCCH transmission. Therefore, in some embodiments, a change or deactivation of a power saving mode may be notified in a DCI transmitted using a first PDCCH transmission to which the new scheme applies. 
     The indicated power saving mode may be considered active until a further indication is received to the contrary. 
     In some embodiments, an indication of the activated power saving mode may comprise an indication that one or more rows the preconfigured TDRA table will not be used, i.e. will be ‘deactivated’. For example, activation of a power saving mode defining a PDSCH time window end as described herein may be indicated by means of an indication that one or more rows of the preconfigured TDRA table are not applicable, the one or more rows being those which may be used to indicate PDSCH resources which finish later than N PDCCH  symbols after an associated DCI. 
     The indication of the one or more deactivated rows may comprise a bitmap, with each bit corresponding to a row of the preconfigured TDRA table, a first setting (e.g. ‘1’) of the bit indicating that the row is not deactivated, and a second setting (e.g. ‘0’) of the bit indicating that the row is deactivated. 
     In some embodiments, the communications device  270  is preconfigured with two or more TDRA tables, one or more of which is associated with a respective power saving mode. For example, a first preconfigured table may comprise only entries which indicate PDSCH resources finishing no later than N PDCCH  symbols after the end of a corresponding DCI, associated with a power saving mode defining a PDSCH time window end as described herein. A second preconfigured table may comprise entries which indicate PDSCH resources finishing later than N PDCCH  symbols after the end of a corresponding DCI. The indication of the activated power saving mode may comprise an indication of which of the two or more preconfigured TDRA tables are to be used (i.e. activated) for subsequent resource allocations. 
     Different Inapplicable Rows 
     As described above, where a power saving scheme based on a PDSCH time window end is used, a row of a configured TDRA table may be determined to be inapplicable, based on a determination that communications resources allocated in accordance with the parameters of that row would not be compatible with the power saving scheme. 
     In some embodiments, a similar determination may be made in respect of a row for other power savings schemes. For example, returning to the example of  FIG. 7 , if cross-slot scheduling is applied, then TDRA index values 0 and 1 may be determined to be inapplicable, because the corresponding PDSCH resource allocation would start prior to the slot (slot n+1) after the slot in which the PDCCH transmission  702  occurs. 
     As described above, parameters associated with inapplicable rows may be adapted in accordance with predetermined rules, such that each row is associated with parameters indicating PDSCH resources which are in compliance with the applicable power saving mode. 
     In some embodiments, one or both of the inapplicable rows and the adapted parameters corresponding to those rows may be associated with a particular power savings scheme. 
     Accordingly, the communications device  270  may determine which (if any) power saving mode is activated. Based on the activated power saving mode, the communications device  270  may determine which (if any) rows of the configured TDRA table are inapplicable and, for an inapplicable row, may determine adapted parameters for that row based on the activated power saving mode. 
     An example of such adapted parameters corresponding to the TDRA table of Table 2, in the example of  FIG. 7  is shown in Table 4. 
     
       
         
           
               
             
               
                 TABLE 4 
               
             
            
               
                   
               
               
                 Modified TDRA entries for PDSCH based on power saving scheme 
               
            
           
           
               
               
               
            
               
                   
                 Replacement for scheme 
                 Replacement for 
               
            
           
           
               
               
               
               
            
               
                   
                 Configured 
                 defining PDSCH 
                 cross-slot 
               
               
                 TDRA 
                 parameters 
                 time window end 
                 scheduling scheme 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                 Index 
                 K 0   
                 S 
                 L 
                 K 0   
                 S 
                 L 
                 K 0   
                 S 
                 L 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                 0 
                 0 
                 2 
                 4 
                 n/a 
                 n/a 
                 n/a 
                 1 
                 2 
                 4 
               
               
                 1 
                 0 
                 10 
                 4 
                 n/a 
                 n/a 
                 n/a 
                 1 
                 10 
                 4 
               
               
                 2 
                 1 
                 0 
                 2 
                 n/a 
                 n/a 
                 n/a 
                 n/a 
                 n/a 
                 n/a 
               
               
                 3 
                 2 
                 7 
                 7 
                 0 
                 12 
                 2 
                 n/a 
                 n/a 
                 n/a 
               
               
                   
               
            
           
         
       
     
     As can be seen in Table 4, the configured parameters associated with index values 0 and 1 are incompatible with a cross-slot scheduling scheme, since they indicate an allocation of communications resources within the same timeslot as the PDCCH transmission. Accordingly, replacement parameters having K 0 =1 are defined for those index values where cross-slot scheduling is activated. 
     TDRA Delay Parameters 
     As described above, in accordance with conventional techniques, each row of a TDRA table may be associated with a K 0  parameter which indicates a timeslot within which the allocated PDSCH communications resources begin, and an S parameter which indicates an offset from the beginning of the timeslot, measured in OFDM symbol periods. 
     However, it has been recognised that a K 0  value indicating that the allocated PDSCH communications resources begin in a slot after that in which the PDCCH transmission occurs (i.e. K 0  equal to 1 or greater) may not be suitable for a power saving scheme which is suited for low latency data transmission, such as that described herein which defines a PDSCH time window end. 
     Accordingly, in some embodiments, the parameter K 0  is defined to indicate a delay in units of less than one timeslot. For example, in some embodiments, the K 0  parameter indicates a number of symbol periods. 
     In some embodiments of the present technique, a parameter associated with a row of a TDRA table may indicate a start offset relative to one of the start of the PDCCH, the end of the PDCCH, the earliest start time of any possible PDCCH transmission within the PDCCH search space, and the latest end time of any possible PDCCH transmission within the PDCCH search space. The start offset may be indicated in units of OFDM symbols. 
     For example, the parameter may indicate a number of OFDM symbol periods between the start of a PDCCH transmission and the start of the allocated PDSCH communications resources. 
     In some embodiments, instead of a ‘slot’ parameter (such as K 0 ) and a ‘symbol’ parameter (such as S), only a single parameter (which may be referred to as K 0 ′ or S′) is used to indicate a delay between a reference time point and a start time of the allocated resources. 
       FIG. 9  shows an example of downlink communications resources  904  allocated by means of a PDCCH transmission  902  in accordance with embodiments of the present technique. The PDCCH transmission  902  starts at time t 0 . The PDCCH transmission  902  comprises DCI which indicates a TDRA index to a row of a configured TDRA table. In the example of  FIG. 9 , the indicated table row is associated with a K 0 ′ value of 2, which indicates that the PDSCH communications resources  904  begin 2 OFDM symbols after time t 0  (the start time of the PDCCH), i.e. at time t 1 . 
     Since URLLC has a low latency requirement, large K 0  values in the TDRA table are unlikely to be used and hence it more beneficial to use a smaller granularity indicator. For power saving purposes, the value of K 0  is also limited in order to ensure PDSCH ends within a predetermined time period after the start of the PDCCH i.e. by the PDSCH time window end. 
     In some embodiments, the TDRA table for uplink (e.g. PUSCH) communications resource assignments provides a K 0 ′ parameter as described above. 
       FIG. 10  illustrates an allocation of uplink communications resources in accordance with embodiments of the present technique. In  FIG. 10 , uplink communications resources  950  and downlink communications resources  952  of a wireless access interface are shown. 
     A PDCCH transmission  954  is shown from time t 0  to time t 1 , which may be in accordance with a PDCCH search space. 
     The communications device  270  is configured with a TDRA table in which the delay from the start of the PDCCH transmission  954  to a start of allocated PDSCH resources is indicated, by means of a K 0 ′ parameter, in units of OFDM symbol periods. An example of such a table is shown in Table 5. 
     
       
         
           
               
             
               
                 TABLE 5 
               
             
            
               
                   
               
               
                 TDRA entries for PUSCH 
               
            
           
           
               
               
               
            
               
                 TDRA Index 
                 K 0 ′ 
                 L 
               
               
                   
               
            
           
           
               
               
               
            
               
                 0 
                 0 
                 4 
               
               
                 1 
                 5 
                 4 
               
               
                 2 
                 0 
                 2 
               
               
                 3 
                 5 
                 2 
               
               
                   
               
            
           
         
       
     
     The PDCCH transmission  954  comprises DCI indicating a TDRA table index, which in the example of  FIG. 10  and Table 5 is index  1 . According to the TDRA table shown in Table 5, an index of 1 corresponds to a K 0 ′ value of 5. Accordingly, allocated PUSCH resources  956  start at time t 2  (being 5 OFDM symbols after the start of the PDCCH transmission) and have a duration of 4 OFDM symbols. 
     In some embodiments, as shown in the example of Table 5, a row of the TDRA table which is associated with a K 0 ′ parameter is not associated with any S parameter, or any associated S parameter is not used to indicate or determine the PDSCH or PUSCH resources. 
     If, as in some embodiments, a row of the TDRA table is associated with an S parameter providing an indication of a delay in symbols from a reference time to a PDSCH resource start time, then in some embodiments such a row is not associated with any K 0  parameter, or any associated K 0  parameter is not used to indicate or determine the PDSCH resources. 
     PDSCH Time Window Start 
     As described above, in some embodiments of the present technique, a PDSCH time window end is defined, according to which the infrastructure equipment  272  schedules a PDSCH transmission to end at or prior to the PDSCH time window end, and the communications device  270  may disable part or all of its receiver  292  after the PDSCH time window end, even if it has not completed decoding of a corresponding PDCCH transmission (or potential PDCCH transmission). 
     In some embodiments, in addition or alternatively, a PDSCH time window start is defined. According to such embodiments, the infrastructure equipment  272  schedules a PDSCH transmission to begin no sooner than the PDSCH time window start, and the communications device  270  may disable part or all of its receiver  292  prior to the PDSCH time window start. 
     In some embodiments, the PDSCH time window start may occur prior to the start of the PDCCH transmission. 
     In some embodiments, the PDSCH time window start may occur between the start of the PDCCH transmission and the end of the PDCCH transmission. 
     In some embodiments, the PDSCH time window start may occur after the end of the PDCCH transmission. In such embodiments, prior to the PDSCH time window start, the communications device  270  may configure its receiver to receive signals which may be used for the PDCCH transmission in accordance with the PDCCH search space. Because the PDCCH transmission may use a narrower bandwidth (i.e. fewer resources when measured in the frequency domain), power consumption associated with receiving signals which may be used for the PDCCH transmission in accordance with the PDCCH search space may be lower than a power consumption associated with receiving signals which may be used for a PDSCH transmission. 
     Where both a PDSCH time window start and a PDSCH time window end are defined, the PDSCH time window start occurs prior to the PDSCH time window end. 
       FIG. 11  shows an example of a scheduled PDSCH transmission in accordance with embodiments of the present technique. 
     In the example of  FIG. 11 , a DL Grant within a DCI  1002  transmitted on a PDCCH starts at time t 0  and ends at time t 1 . The PDSCH time window start is determined based on a predetermined parameter N START . Accordingly, the PDSCH time window start occurs at time t 2 , which is N START  symbols after the start of the PDCCH  1002 . During the time between t 1  and t 2 , the communications device  270  may disable part or all of its RF receiver for receiving and buffering of downlink signals, since the communications device  270  does not expect any PDSCH communications resources to be allocated before time t 2 . Examples of disabling part or all of the RF receiver chain may include turning off certain oscillators, clock sources, analogue to digital conversion circuits and/or amplifiers within the receiver  292 . It may additionally or alternatively comprise operating the RF receiver chain at a lower operating voltage, leading to a performance degradation of the RF receiver chain. In any case, power consumption associated with the receiver  292  may be lowered as a result of disabling the parts or all of the RF receiver chain and/or operating the RF receiver chain at the lower operating voltage. 
     In the example of  FIG. 11 , PDSCH communications resources  1004  are allocated starting at time t 3 , i.e. no earlier than the PDSCH time window start at time t 2 . 
     In some embodiments, the configured TDRA table may comprise rows which indicate PDSCH resources which start prior to the PDSCH time window start. In some embodiments, the PDSCH time window start takes precedence over these rows. That is, instead of controlling the receiver  290  to receive and buffer signals which may comprise allocated PDSCH resources, based on the allocations which may be indicated by means of an index to a row of the TDRA table, the communications device  270  controls its receivers  290  based on the PDSCH time window start. 
     Accordingly, one or more of the TDRA table rows which indicate PDSCH resources which start prior to the PDSCH time window start may be determined to be inapplicable by the communications device  290  and/or by the infrastructure equipment  272 . 
     Following the same principle described above in the context of the PDSCH time window end, parameters associated with one or more of the TDRA rows which are determined to be inapplicable based on the determined PDSCH time window start may be adapted in accordance with predetermined rules, such that the associated TDRA row index instead corresponds to parameters indicating PDSCH communications resources which are compliant with (i.e. do not start before) the determined PDSCH time window start. 
     An indication of a predetermined parameter by which the PDSCH time window start can be determined (such as the N START  parameter described above) may be transmitted by the infrastructure equipment  272  to the communications device  270  using one or more of RRC signalling, MAC signalling, or DCI signalling. 
     In the case of the indication by DCI signalling, an indication of the N START  value can be included within a different DCI from a DCI scheduling the PDSCH to which the N START  value is applicable. The DCI comprising the N START  indication can be transmitted prior to a DCI scheduling the PDSCH, e.g. in a previous slot. 
     In some embodiments, the PDSCH time window start may correspond to the end of the PDCCH transmission. For example, the N START  parameter may be equal to T PDCCH , where T PDCCH  is the transmission time of the PDCCH transmission. 
     In the example of  FIG. 11 , the PDSCH time window start is at time t 2 . According to conventional techniques, the PDCCH transmission  1002  may allocate PDSCH communications resources starting at the first symbol of the same timeslot in which the PDCCH transmission  1002  occurs, i.e. at time t 0 . However, in accordance with embodiments of the present technique, from time t 0  until t 1 , in accordance with the PDCCH search space, the communications device  270  is required to receive only signals which may correspond to the PDCCH transmission  1002 . 
     This means that, at least between time t 0  and time t 1 , the UE may operate its receiver  292  in a manner sufficient to receive the PDCCH. This manner may be associated with a lower power consumption than a manner in which reception of PDSCH signals is possible. For example, the receiver  292  may be configured to receive using only a narrow bandwidth for PDCCH between t 0  and t 1 , thereby reducing the power consumption of the communications device  270 . Furthermore, where the PDSCH time window start occurs after the end of the PDCCH transmission (as in the example of  FIG. 11 ), the communications device  270  may disable part or all of its receiver  290  during the time period between the end of the PDCCH transmission  1002  and the PDSCH time window start, i.e. between time t 1  and t 2  in the example of  FIG. 11 . 
     In other examples, the receiver may be configured to operate to receive PDCCH signals using a smaller number of receive antennas or MIMO layers than would be required to receive PDSCH signals, thus saving power. 
     In some embodiments, the infrastructure equipment  272  determines that the communications device  270  configures its receiver  292  to operate in a different manner when receiving PDCCH signals, as described above, and adapts the scheduling and/or transmission of PDCCH signals accordingly, in order to ensure the reliable reception of messages (such as DCI) via the PDCCH. For example, the infrastructure equipment  272  may determine an effective signal to noise ratio (SNR) at the communications device  270 , taking into account (for example) the number of receive antennas used by the communications device  270 , and apply a suitable level of redundancy to the PDCCH transmissions. 
     In some embodiments, the PDSCH time window start is determined implicitly based on the PDCCH processing time N PDCCH  mentioned above. The PDCCH processing time N PDCCH  may be implicitly determined by the infrastructure equipment  272  based on a maximum number of blind decoding attempts that may be required by the communications device  270  to successfully decode the PDCCH transmission (or to determine that no PDCCH transmission has occurred in accordance with the PDCCH search space). Because the infrastructure equipment  272  configures the PDCCH search space, it is able to determine the maximum number of blind decoding attempts that may be required. The PDCCH processing time N PDCCH  for the communications device  270  may be determined in accordance with a predetermined mapping which may be based on a capability of the communications device  270 . The PDCCH processing time is an example of a decoding delay. A maximum decoding delay may be a maximum time that the communications device  270  requires to decode a message (such as DCI) transmitted using the PDCCH, and may be signalled as a capability of the communications device, be derived from a capability of the communications device and/or be preconfigured at both the communication device and the infrastructure equipment in accordance with a standards specification. 
     For example, if the maximum number of blind decoding attempts is 22 (respectively 44), then in accordance with such a mapping, the PDCCH processing time N PDCCH  may be determined to be 2 (respectively 4) symbols. 
     In some embodiments, one or more of the methods for determining N PDCCH  described above in the context of determining the PDSCH time window end may be used. 
     UE Process Flowchart 
       FIG. 12  illustrates a flowchart for a process of receiving data by the communications device  270  from the infrastructure equipment  272  in accordance with embodiments of the present technique. 
     The process starts at step S 1102  in which the communication device  270  determines a PDCCH search space, which characterises communication resources on which a downlink control information may be transmitted by the infrastructure equipment  272 . The downlink control information may indicate allocated downlink communication resources for the transmission of data to the communications device  270 . 
     Control then passes to step S 1104 , in which the communications device  270  determines whether a power saving mode is associated with the PDCCH search space. Control then passes to step S 1106 , in which the communications device  270  determines whether the power saving mode determined in step S 1104  defines a PDSCH time window end. 
     If, at step S 1106 , it is determined that the power saving mode associated with the PDCCH search space does not define a PDSCH time window end, then control passes to S 1108  in which the communications device  270  uses conventional techniques to receive the PDCCH transmission and to determine if a PDSCH transmission is scheduled. Furthermore if it is determined that a PDSCH transmission is scheduled then in step S 1108 , the communications device  270  receives the signals associated with the PDSCH and decodes them in accordance with conventional techniques. The process then ends. 
     If, at step S 1106 , it is determined that the power saving mode defines a PDSCH time window end, then control passes to step S 1110 , in which the communications device  270  determines the PDSCH time window end associated with the PDCCH search space. As described above, the PDSCH time window end may be determined by reference to the start of the PDCCH transmission, the end of the PDCCH transmission or the start or end of the communications resources within which the PDCCH transmission may occur. 
     Control passes then to step S 1112 , in which the communications device  270  determines whether one or more rows of the TDRA table are inapplicable based on the end time of PDSCH communication resources as indicated by the configured TDRA table, and based on the determined PDSCH time window end. 
     Control then passes to step S 1114 , in which the communications device  270  determines adapted parameters for any inapplicable TDRA rows, the adapted parameters being compliant with the determined PDSCH time window end. 
     Control then passes to step S 1116 , in which the communications device  270  controls its receiver  292  to receive signals transmitted using communication resources associated with the PDCCH search space, in which the downlink control information may be transmitted. 
     In step S 1118 , the communications device  270  controls its receiver  292  to receive signals transmitted on communication resources on which a PDSCH transmission to the communications device  270  may occur in accordance with the determined PDSCH time window end parameter and the parameters associated with the rows of the TDRA table. The parameters associated with the rows of the TDRA table may be those of the configured table, which have been determined to be applicable in step S 1112 , or may be parameters which have been adapted in step S 1114 . 
     Control then passes to step S 1120 , in which the communications device  270  controls its receiver to buffer signals received which may comprise a PDSCH transmission. Control then passes to step S 1122 , in which the communications device  270  determines whether the PDSCH time window end determined at step S 1110  has passed. If the PDSCH time window end has not passed, then control returns to step S 1120 . 
     If at step S 1122  it is determined that the PDSCH time window end has passed, then control passes to step S 1124 . At step S 1124 , the communications device  270  may control its receiver  292  to terminate reception of signals, based on the determination that the PDSCH time window has now passed, and therefore that in accordance with the PDSCH time window end, the infrastructure equipment  272  is no longer transmitting a PDSCH transmission to the communications device  270 . 
     As described above, because of the requirement for the communications device  270  to perform blind decoding of signals associated with the PDCCH search space, the communications device  270  is required to receive and buffer signals which may be corresponding to a PDSCH transmission to the communications device while the decoding of the PDCCH signals is taking place. 
     Accordingly, at step S 1126  the communications device  270  decodes the signals which were received in accordance with the enabling of the receiver  292  at step S 1116 . That is, the communications device  270  attempts to blind decode a PDCCH transmission comprising downlink control information transmitted to the communications device in accordance with the PDCCH search space determined at step S 1102 . 
     At step S 1128 , the communications device  270  determines whether the signals received in accordance with the PDCCH search space and blindly decoded at step S 1126  include downlink control information allocating communication resources on the PDSCH for the communication of data by the infrastructure equipment  272  to the communications device  270 . If it is determined that no such PDSCH allocation has occurred, for example because no downlink control information has been transmitted, then control passes to step S 1130  and the process ends. 
     If it is determined at step S 1128  that downlink control information was transmitted by the infrastructure equipment to the communications device allocating communication resources on the PDSCH, then control passes to step S 1132 , in which the communications device  270  decodes data from the signals which were received and buffered in step S 1118  and step S 1120 . Control then passes to step S 1130  and the process ends. 
     gNB Process 
     In accordance with embodiments of the present technique, a corresponding process is described for the infrastructure equipment  272  and illustrated in  FIG. 13 . 
     The process starts at step S 1202  in which the infrastructure equipment  272  configures a PDCCH search space and associated power saving mode for the communications device  270 . This step may comprise transmitting, for example in RRC signalling, an indication of the PDCCH search space parameters, an indication of the associated power saving mode and an indication of parameters associated with the power saving mode. For example, the associated power saving mode may be one which defines both a PDSCH time window start and a PDSCH time window end, for each PDSCH allocated by means of DCI transmitted in accordance with the PDCCH search space. Accordingly, the parameters associated with the power saving mode may comprise an N START  parameter and an N END  parameter. 
     The process continues with step S 1204  in which the infrastructure equipment  272  determines that it has downlink data for transmission to the communications device  270 . 
     At step S 1206 , the infrastructure equipment allocates PDSCH communications resources for the transmission of the data and allocates PDCCH communications resources for transmission of DCI indicating the allocated PDSCH communications resources. The infrastructure equipment ensures that the PDCCH communications resources are in accordance with the PDCCH search space configured in step S 1202 , and that the PDSCH communications resources are compliant with the power saving mode and associated parameters. For example, the infrastructure equipment  272  may ensure that the PDSCH communications resources do not start prior to the PDSCH time window start (in accordance with the N START  parameter) and do not extend beyond the PDSCH time window end (in accordance with the N END  parameter). 
     In step S 1208  the infrastructure equipment  272  transmits the DCI using the determined PDCCH communications resources, and at step S 1210 , the infrastructure equipment  272  transmits the downlink data using the determined PDSCH communications resources. 
     In some embodiments, the infrastructure equipment  272  may configure PDCCH search spaces, power saving modes and associated parameters for multiple communications devices. In some embodiments, these are configured so that the corresponding PDSCH time windows do not overlap, or overlap to a minimal extent. In some embodiments, this may comprise configuring PDCCH search spaces for different communications devices such that the PDCCH search spaces start at different time and/or do not overlap. Accordingly, embodiments of the present technique provide for power saving techniques to be implemented in respect of multiple communications devices while ensuring efficient usage of PDSCH and/or PDCCH communications resources. 
     It will be appreciated that within the scope of the present disclosure, the processes illustrated in  FIG. 12  and in  FIG. 13  and described above may be adapted by means of the modification, addition, removal or re-ordering of one or more steps. For example, where the configured TDRA table indicates that allocated PDSCH may start earlier than the beginning of the PDCCH transmission, the order of steps S 1116  and S 1118  may be reversed. Similarly, step S 1126  may be carried out in parallel with one or more of steps S 1118 , S 1120 , S 1122  and S 1124 . 
     Aspects of embodiments described herein may be combined in manners not otherwise explicitly described. For example, in some embodiments, the PDSCH time window may be characterised by both a PDSCH time window start, as described herein, and by a PDSCH time window end, as described above. Accordingly, the infrastructure equipment  272  may schedule the transmission of DCI scheduling resources on a shared channel such as a PDSCH, wherein the shared channel resources are compliant with (i.e. do not extend beyond) the PDSCH time window start or the PDSCH time window end. 
     Similarly, the communications device  270  may control its receiver  292  (and in particular its RF receiver chain) to receive signals of the shared channel after the PDSCH time window start and before the PDSCH time window end, and to operate its receiver  292  in a lower power mode of operation before and after the PDSCH time window. 
     Thus there has been described a method for receiving data by a communications device from a wireless communications network, the method comprising: receiving a downlink control message transmitted in first downlink communications resources of a wireless access interface provided by the wireless communications network, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, decoding the downlink control message to identify the second downlink communications resources for receiving the downlink data, and receiving the downlink data from the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded. 
     There has also been described a method for receiving data by a communications device from a wireless communications network, the method comprising: receiving a downlink control message transmitted in first downlink communications resources of a wireless access interface provided by the wireless communications network, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, decoding the downlink control message to identify the second downlink communications resources for receiving the downlink data, and receiving the downlink data from the second downlink communications resources, wherein the second downlink communications resources are within a time period of the wireless access interface which starts at a pre-configured start time, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Corresponding communications devices, infrastructure equipment and methods therefore, and circuitry for a communications device and circuitry for infrastructure equipment have also been described. 
     It will be appreciated that while the present disclosure has in some respects focused on implementations in an LTE-based and/or 5G network for the sake of providing specific examples, the same principles can be applied to other wireless telecommunications systems. Thus, even though the terminology used herein is generally the same or similar to that of the LTE and 5G standards, the teachings are not limited to the present versions of LTE and 5G and could apply equally to any appropriate arrangement not based on LTE or 5G and/or compliant with any other future version of an LTE, 5G or other standard. 
     It may be noted various example approaches discussed herein may rely on information which is predetermined/predefined in the sense of being known by both the base station and the communications device. It will be appreciated such predetermined/predefined information may in general be established, for example, by definition in an operating standard for the wireless telecommunication system, or in previously exchanged signalling between the base station and communications devices, for example in system information signalling, or in association with radio resource control setup signalling, or in information stored in a SIM application. That is to say, the specific manner in which the relevant predefined information is established and shared between the various elements of the wireless telecommunications system is not of primary significance to the principles of operation described herein. It may further be noted various example approaches discussed herein rely on information which is exchanged/communicated between various elements of the wireless telecommunications system and it will be appreciated such communications may in general be made in accordance with conventional techniques, for example in terms of specific signalling protocols and the type of communication channel used, unless the context demands otherwise. That is to say, the specific manner in which the relevant information is exchanged between the various elements of the wireless telecommunications system is not of primary significance to the principles of operation described herein. 
     It will be appreciated that the principles described herein are not applicable only to certain types of communications device, but can be applied more generally in respect of any types of communications device, for example the approaches are not limited to machine type communication devices/IoT devices or other narrowband communications devices, but can be applied more generally, for example in respect of any type of communications device operating with a wireless link to the communication network. 
     It will further be appreciated that the principles described herein are not applicable only to LTE-based wireless telecommunications systems, but are applicable for any type of wireless telecommunications system that supports a dynamic scheduling of shared communications resources. 
     Further particular and preferred aspects of the present invention are set out in the accompanying independent and dependent claims. It will be appreciated that features of the dependent claims may be combined with features of the independent claims in combinations other than those explicitly set out in the claims. 
     Thus, the foregoing discussion discloses and describes merely exemplary embodiments of the present invention. As will be understood by those skilled in the art, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the disclosure of the present invention is intended to be illustrative, but not limiting of the scope of the invention, as well as other claims. The disclosure, including any readily discernible variants of the teachings herein, define, in part, the scope of the foregoing claim terminology such that no inventive subject matter is dedicated to the public. 
     Respective features of the present disclosure are defined by the following numbered paragraphs: 
     Paragraph 1. A method for receiving data by a communications device from a wireless communications network, the method comprising: receiving a downlink control message transmitted in first downlink communications resources of a wireless access interface provided by the wireless communications network, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, decoding the downlink control message to identify the second downlink communications resources for receiving the downlink data, and receiving the downlink data from the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded. 
     Paragraph 2. A method according to paragraph 1, wherein the decoding starts after an end of the first downlink communications resources. 
     Paragraph 3. A method according to paragraph 1 or paragraph 2, wherein the decoding starts after the first downlink communications resources begin. 
     Paragraph 4. A method according to any of paragraphs 1 to 3, the method comprising controlling a receiver of the communications device to receive signals during the time window and controlling the receiver to operate with a reduced power consumption after the pre-configured end time. 
     Paragraph 5. A method according to paragraph 4 wherein controlling the receiver to operate with a reduced power consumption comprises disabling one or more radio frequency (RF) components within the receiver. 
     Paragraph 6. A method according to any of paragraphs 1 to 5, wherein the pre-configured end time is a predetermined duration after the end of the first downlink communications resources. 
     Paragraph 7. A method according to any of paragraphs 1 to 6, wherein the pre-configured end time is before a maximum decoding delay for decoding the downlink control message after the end of the first downlink communications resources. 
     Paragraph 8. A method according to any of paragraphs 1 to 5, wherein the pre-configured end time is a predetermined duration after the start of the first downlink communications resources. 
     Paragraph 9. A method according to any of paragraphs 1 to 8, wherein the downlink control message comprises an indication of an index value of a predetermined table, the predetermined table comprising a plurality of index values and, for each of the plurality of index values, an indication of communications resources, and the second downlink communications resources are associated with the index value indicated by the downlink control message. 
     Paragraph 10. A method according to any of paragraphs 1 to 9, wherein the pre-configured end time is a latest end time of any communications resources associated with an index value of the predetermined table. 
     Paragraph 11. A method according to paragraph 9, the method comprising receiving an indication that one or more index values of the predetermined table are deactivated, wherein the pre-configured end time is a latest end time of any communications resources associated with an index value of the predetermined table which is not deactivated. 
     Paragraph 12. A method according to any of paragraphs 9 to 11, the method comprising receiving an indication that the predetermined table is activated, wherein the predetermined table is one of a plurality of predetermined tables. 
     Paragraph 13. A method according to any of paragraphs 1 to 9, wherein the downlink control message comprises an indication of an index value of a predetermined table, the predetermined table comprising a plurality of index values and, for each of the plurality of index values, an indication of communications resources, the method comprising determining that the communications resources associated with the index value indicated by the downlink control message end after the pre-configured end time, and determining the second communications resources based on the index value indicated by the downlink control message in accordance with a predetermined rule for adapting the communications resources which are associated with an index value indicated by a downlink control message and which end after the pre-configured end time. 
     Paragraph 14. A method according to any of paragraphs 9 to 13, wherein each index value of the predetermined table is associated with a delay value, the delay value indicating a number of orthogonal frequency division multiplexing (OFDM) symbol periods between a start of the first downlink communications resources and a start of the second downlink communications resources. 
     Paragraph 15. A method according to any of paragraphs 1 to 14, the method comprising: determining that a first power-saving mode is in operation, wherein according to the first power-saving mode, the pre-configured end time is no later than a maximum decoding delay for decoding the downlink control message after the end of the first downlink communications resources. 
     16. A method according to paragraph 15, the method comprising determining the pre-configured end time in response to determining that the first power-saving mode is in operation. 
     Paragraph 17. A method according to paragraph 15 or paragraph 16, wherein the first downlink communications resources are determined in accordance with a predetermined schedule defining a plurality of downlink communications resources which may be used for the transmission of downlink control messages to the communications device. 
     Paragraph 18. A method according to paragraph 17, wherein the predetermined schedule comprises a physical downlink control channel (PDCCH) search space. 
     Paragraph 19. A method according to paragraph 17 or paragraph 18, wherein the predetermined schedule is associated with the first power saving mode. 
     Paragraph 20. A method according to any of paragraphs 15 to 19, the method comprising receiving radio resource control signalling, the radio resource control signalling comprising an indication indicating that the first power saving mode is in operation. 
     Paragraph 21. A method according to any of paragraphs 15 to 20, the method comprising receiving medium access control signalling, the medium access control signalling comprising an indication indicating that the first power saving mode is in operation. 
     Paragraph 22. A method according to any of paragraphs 15 to 21, the method comprising receiving a second downlink control message, the second downlink control message comprising an indication that the first power-saving mode is in operation. 
     Paragraph 23. A method according to any of paragraphs 1 to 22, wherein the time period starts earlier than the first downlink communications resources. 
     Paragraph 24. A method according to any of paragraphs 1 to 22, the method comprising determining a pre-configured start time of a second time period within the time period, the second downlink communications resources being within the second time period, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Paragraph 25. A method according to paragraph 24, the method comprising controlling the receiver of the communications device to stop receiving signals after the end of the first downlink communications resources, and controlling the receiver of the communications device to receive signals after the pre-configured start time of the second time period. 
     Paragraph 26. A method according to paragraph 24 or paragraph 25, wherein the pre-configured start time of the second time period is a predetermined start time delay after the start of the first downlink communications resources. 
     Paragraph 27. A method according to paragraph 26, the method comprising receiving an indication of the predetermined start time delay. 
     Paragraph 28. A method according to paragraph 26 or paragraph 27, wherein the predetermined start time delay is equal to a duration of the first communications resources. 
     Paragraph 29. A method according to any of paragraphs 1 to 28, wherein the downlink control message is transmitted in a first manner allowing reception using less power consumption, and the downlink data is transmitted in a second manner that requires more power consumption than used to receive the first downlink communications resources. 
     Paragraph 30. A method according to paragraph 29 wherein the first manner comprises transmitting over a first bandwidth, and the second manner comprises transmitting over a second bandwidth having a greater range than the first bandwidth. 
     Paragraph 31. A method according to paragraph 29 or paragraph 30 whereby in accordance with the first manner, one or more transmission parameters are determined based on a reception by the communications device using a first number of receive antennas, and in accordance with the second manner, the one or more transmission parameters are determined based on a reception by the communications device using a second number of receive antennas greater than the first number. 
     Paragraph 32. A method for receiving data by a communications device from a wireless communications network, the method comprising: receiving a downlink control message transmitted in first downlink communications resources of a wireless access interface provided by the wireless communications network, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, decoding the downlink control message to identify the second downlink communications resources for receiving the downlink data, and receiving the downlink data from the second downlink communications resources, wherein the second downlink communications resources are within a time period of the wireless access interface which starts at a pre-configured start time, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Paragraph 33. A method for transmitting data to a communications device in a wireless communications network, the method comprising: transmitting a downlink control message in first downlink communications resources of a wireless access interface provided by the wireless communications network, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, and transmitting the downlink data using the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded by the communications device. 
     Paragraph 34. A method according to paragraph 33, the method comprising transmitting a second downlink control message in third downlink communications resources of the wireless access interface, the second downlink control information providing an indication of fourth downlink communications resources from which another communications device can receive second downlink data, and transmitting the second downlink data using the fourth downlink communications resources, wherein the third downlink communications resources and the fourth downlink communications resources are within a third time period of the wireless access interface which ends at a second pre-configured end time, the pre-configured end time being before the downlink control message is decoded by the other communications device, the time period and the third time period being non-overlapping. 
     Paragraph 35. A method according to paragraph 34, wherein the first downlink communications resources are determined in accordance with a first predetermined schedule defining a first plurality of downlink communications resources which may be used for the transmission of downlink control messages to the communications device, the third downlink communications resources are determined in accordance with a second predetermined schedule defining a second plurality of downlink communications resources which may be used for the transmission of downlink control messages to the other communications device, and the first plurality of downlink communications resources and the second plurality of downlink communications resources do not overlap in time. 
     Paragraph 36. A method according to paragraph 35, the method comprising: transmitting an indication of the first predetermined schedule to the communications device, and transmitting an indication of the second predetermined schedule to the other communications device. 
     Paragraph 37. A method for transmitting data to a communications device in a wireless communications network, the method comprising: transmitting a downlink control message in first downlink communications resources of a wireless access interface provided by the wireless communications network, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, and transmitting the downlink data using the second downlink communications resources, wherein the second downlink communications resources are within a time period of the wireless access interface which starts at a pre-configured start time, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Paragraph 38. A communications device for use in a wireless communications network, the wireless communications network comprising an infrastructure equipment providing a wireless access interface, the communications device comprising a transmitter configured to transmit uplink data via the wireless access interface, a receiver configured to receive signals, and a controller configured to control the transmitter and the receiver so that the communications device is operable: to receive a downlink control message transmitted in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, to decode the downlink control message to identify the second downlink communications resources for receiving the downlink data, and to receive the downlink data from the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded. 
     Paragraph 39. Circuitry for a communications device for use in a wireless communications network, the wireless communications network comprising an infrastructure equipment providing a wireless access interface, the circuitry comprising transmitter circuitry configured to transmit data via the wireless access interface, receiver circuitry configured to receive signals, and controller circuitry configured to control the transmitter circuitry and the receiver circuitry so that the communications device is operable: to receive a downlink control message transmitted in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, to decode the downlink control message to identify the second downlink communications resources for receiving the downlink data, and to receive the downlink data from the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded. 
     Paragraph 40. A communications device for use in a wireless communications network, the wireless communications network comprising an infrastructure equipment providing a wireless access interface, the communications device comprising a transmitter configured to transmit uplink data via the wireless access interface, a receiver configured to receive signals, and a controller configured to control the transmitter and the receiver so that the communications device is operable: to receive a downlink control message transmitted in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, to decode the downlink control message to identify the second downlink communications resources for receiving the downlink data, and to receive the downlink data from the second downlink communications resources, wherein the second downlink communications resources are within a time period of the wireless access interface which starts at a pre-configured start time, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Paragraph 41. Circuitry for a communications device for use in a wireless communications network, the wireless communications network comprising an infrastructure equipment providing a wireless access interface, the circuitry comprising transmitter circuitry configured to transmit data via the wireless access interface, receiver circuitry configured to receive signals, and controller circuitry configured to control the transmitter circuitry and the receiver circuitry so that the communications device is operable: to receive a downlink control message transmitted in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, to decode the downlink control message to identify the second downlink communications resources for receiving the downlink data, and to receive the downlink data from the second downlink communications resources, wherein the second downlink communications resources are within a time period of the wireless access interface which starts at a pre-configured start time, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Paragraph 42. Infrastructure equipment for use in a wireless communications network, the infrastructure equipment providing a wireless access interface, the infrastructure equipment comprising a transmitter configured to transmit signals to a communications device via the wireless access interface in a cell, a receiver configured to receive data from the communications device, and a controller, configured to control the transmitter and the receiver so that the infrastructure equipment is operable: to transmit a downlink control message in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, and to transmit the downlink data using the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded by the communications device. 
     Paragraph 43. Circuitry for an infrastructure equipment for use in a wireless communications network, the infrastructure equipment providing a wireless access interface, the circuitry comprising transmitter circuitry configured to transmit signals to a communications device via the wireless access interface in a cell, receiver circuitry configured to receive data from the communications device, and controller circuitry, configured to control the transmitter circuitry and the receiver circuitry so that the infrastructure equipment is operable: to transmit a downlink control message in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, and to transmit the downlink data using the second downlink communications resources, wherein the first and the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured end time, the pre-configured end time being before the downlink control message is decoded by the communications device. 
     Paragraph 44. Infrastructure equipment for use in a wireless communications network, the infrastructure equipment providing a wireless access interface, the infrastructure equipment comprising a transmitter configured to transmit signals to a communications device via the wireless access interface in a cell, a receiver configured to receive data from the communications device, and a controller, configured to control the transmitter and the receiver so that the infrastructure equipment is operable: to transmit a downlink control message in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, and to transmit the downlink data using the second downlink communications resources, wherein the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured start time, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Paragraph 45. Circuitry for an infrastructure equipment for use in a wireless communications network, the infrastructure equipment providing a wireless access interface, the circuitry comprising transmitter circuitry configured to transmit signals to a communications device via the wireless access interface in a cell, receiver circuitry configured to receive data from the communications device, and controller circuitry, configured to control the transmitter circuitry and the receiver circuitry so that the infrastructure equipment is operable: to transmit a downlink control message in first downlink communications resources of the wireless access interface, the downlink control information providing an indication of second downlink communications resources from which the communications device can receive downlink data, and to transmit the downlink data using the second downlink communications resources, wherein the second downlink communications resources are within a time period of the wireless access interface which ends at a pre-configured start time, the pre-configured start time being before the downlink control data is decoded and after the first downlink communications resources. 
     Further particular and preferred aspects of the present invention are set out in the accompanying independent and dependent claims. It will be appreciated that features of the dependent claims may be combined with features of the independent claims in combinations other than those explicitly set out in the claims. 
     REFERENCES 
     [1] RP-182090, “Revised SID: Study on NR Industrial Internet of Things (IoT),” 3GPP RAN#81. 
     [2] Holma H. and Toskala A, “LTE for UMTS OFDMA and SC-FDMA based radio access”, John Wiley and Sons, 2009 
     [3] 3GPP TS 38.321, “Medium Access Control (MAC) protocol specification (Rel-15)”, v15.3.0 
     [4] 3GPP TS 38.214 “NR; Physical layer procedures for data (Release 15)”, version 15.2.0 
     [5] 3GPP TS 38.300 v. 15.4.0 “NR; NR and NG-RAN Overall Description; Stage 2 (Release 15)” 
     [6] 3GPP TS 38.825 
     [7] RP-190727, “New WID: UE Power Saving in NR”, CATT, CAICT, 3GPP RAN#83