GB2572586A

GB2572586A - A method and system to support UL multiplexing with repetition

Info

Publication number: GB2572586A
Application number: GB1805524.4A
Authority: GB
Inventors: Liu Guang; Marco Olivier; Teicher Haim
Original assignee: TCL Communication Ltd
Current assignee: TCL Communication Ltd
Priority date: 2018-04-04
Filing date: 2018-04-04
Publication date: 2019-10-09
Also published as: CN112055991A; WO2019192330A1; GB201805524D0

Abstract

The invention relates to the use of bundles of repeatedly transmitted transport blocks in a method to support uplink multiplexing of packets with different transmission durations, such as Ultra Low Latency Communication (URLLC) and Enhanced Mobile Broadband (eMBB) packets. Scheduled resources for each packet may overlap, and the short duration packets are transmitted with bundle repetition and/or power control. Transmissions of the longer duration packets may fail due to the overlap but can be recovered using HARQ retransmission. Disclosed is a method for enabling a wireless communication device to access services provided by a Radio Access Network between a base station and user equipment, the method comprising the steps of: repeating a transport block before it is buffered and repeating the transmission of a buffered transport block a predetermined number of times, until the packet is successfully decoded.

Description

Technical Field

Embodiments of the present invention generally relate to wireless communication systems and in particular to devices and methods for enabling a wireless communication device, such as a User Equipment (UE) or mobile device to access a Radio Access Technology (RAT) or Radio Access Network (RAN), particularly but nor exclusively multiplexing UL transmissions with different reliabilities.

Background

Wireless communication systems, such as the third-generation (3G) of mobile telephone standards and technology are well known. Such 3G standards and technology have been developed by the Third Generation Partnership Project (3GPP). The 3^rd generation of wireless communications has generally been developed to support macro-cell mobile phone communications. Communication systems and networks have developed towards a broadband and mobile system.

The 3rd Generation Partnership Project has developed the so-called Long Term Evolution (LTE ™) system, namely, an Evolved Universal Mobile Telecommunication System Territorial Radio Access Network, (E-UTRAN), for a mobile access network where one or more macro-cells are supported by a base station known as an eNodeB or eNB (evolved NodeB). More recently, LTE is evolving further towards the so-called 5G or NR (new radio) systems where one or more cells are supported by a base station known as a gNB.

Ultra Reliable Low Latency Communication (URLLC) and some MTC (Machine Type Communication) services require a very short latency (less than 1ms) for small data packets. URLLC is likely to be used for factory control and requires a very high reliability (packet loss rate less than 10^-5). Data packets often arrive in an infrequent and sporadic manner.

To meet the short latency requirement of URLLC type services, NR uses uplink transmission without grant (also called grant free).

Normally Up Link (UL) transmission is scheduled by the base station which uses a UL grant message to indicate a UE which resource can be used for the next UL transmission. This option is called grant based UL transmission. For UL transmission without grant, a set of resources are pre-allocated to the UE for a certain period and the UE can start its transmission without waiting for the downlink scheduling message. Both are illustrated in figure 1 (LHS: grant based; RHS: grant free).

For grant based UL transmission, there is at least one Round Trip Time (RTT) delay (Scheduling Request (SR) + UL Grant) before the initial transmission. For grant free UL transmission, if the pre-allocated resources are available frequently enough, the latency for initial transmission could be very short.

To meet the high reliability requirement of URLLC type services, NR uses transmission repetition which means one data packet could be transmitted K times repeatedly with same or different Redundancy Version (RV), where K is high layer configurable.

The agreed solution is illustrated in Figure 2. Resources are grouped in time period P which is high layer configured, and the UE can start transmission from any occasion marked by an arrow in the figure, but it has to stop at the end of the period P. The starting transmission occasion could be different for different RV sequences and is also high layer configured. The starting occasion needs to be associated with an RV value 0, e.g., a UE can start from any occasion with the RV sequence of {0 0 0 0} or start from any odd occasion with the RV sequence of {0 3 0 3} or start only from the initial occasion with the RV sequence of {0 2 3 1}.

If the configured resources are not shared by any other UE, the resource itself can be used to identify the UE and if two or more UEs are configured to share the same set of resources, different UEs can be differentiated by the used Demodulation Reference Signal (DMRS) sequence and the DMRS sequence is also high layer configured.

Multiple Hybrid Automatic Repeat reQuest (HARQ) processes can be supported for UL grant free transmission, and the HARQ process ID can be obtained with the following agreements from RAN1 #91.

• For UL transmission without UL grant, the HARQ ID associated with the K repetitions of a Transport Block (TB) is derived from the following equation:

HARQ Process ID = floor (X I UL-TWG-periodicity) mod UL-TWGnumbHARQproc • Where X= (SFN * SlotPerFrame * SymbolPerSlot + Slot_index_ln_SF * SymbolPerSlot + Symbol_lndex_ln_Slot) • X refers to the symbol index of the first transmission occasion of repetition bundle that takes place.

The formula can be explained with reference to figure 3. UL-TWG-periodicity is the period P in the number of OS (Orthogonal Frequency Division Multiplexing (OFDM) Symbols), UL-TWG-numbHARQproc is the total number of configured HARQ processes, X is basically the absolute symbol index and each HARQ process has fixed resources in time domain.

A further problem is also illustrated in Figure 3. When a packet is received from an upper layer, after some processing time, there is only one (or any small number) mini-slot of 2 symbols left in the current period P so the UE can only use this mini-slot to transmit the packet. Assuming there is another packet for the other HARQ process, this second packet can be transmitted with all 3 mini-slots of 6 symbols. Obviously, packet #2 is more reliable than packet #1. If packet #1 cannot be decoded, the gNB may switch this UE to the grant based by scheduling dedicated resources together with a Negative Acknowledgement (Nack) indication. This has two drawbacks:

1) The latency of packet #1 is increased and the likelihood of it exceeding the 1 ms limit is dramatically increased, especially in Time Division Duplex (TDD) mode when the Nack indication needs to be delayed until the next Down Link (DL) symbol;

2) since reliability of packet #1 is very low, it increases the reliability requirement of DL Downlink Control Information (DCI) which will result in a higher control signalling overhead. Note that the product of the reliability of the initial transmission bundle (including repetitions) multiplying the reliability of DCI should ideally be well below 10^-5.

One remaining issue is the uplink channel efficiency. For the current solution as above, when a configured resource is not used (all UEs have no data to transmit), it is just wasted and when two or more UEs who want to access this resource occasion simultaneously, collision happens. It is understood that channel waste and collision can be traded but cannot be achieved simultaneously, for instance, when the number of channel resources is infinite, collisions can be completely avoided but the number of wasted channel resources is infinite too.

Figure 4 shows a curve of collision probability vs. channel usage. For URLLC type services, a very high reliability requires a very low collision probability which in turn results in a very low channel usage, for instance, 10^-3 collision probability corresponds to 4.5% channel usage which means 95.5% channel resources are not used and just wasted.

The following possible enhancements have been proposed. For simplicity, URLLC is used as an example of short duration transmission and eMBB is used as an example of long duration transmission but note that the transmission duration is configurable for any service.

In one proposal (1) semi-static multiplexing, resources are pre-allocated to URLLC UEs which access the resources without UL grant (i.e., grant free) and eMBB UEs are dynamically scheduled with two possible designs: (a) Resources not preallocated to URLLC UEs can be scheduled to an eMBB UE (i.e., FDD); and (b) All resources including those pre-allocated to URLLC UEs can be scheduled to an eMBB UE and in this design, URLLC UEs transmit with a higher power than eMBB UEs.

A further proposal (2) suggests two types of dynamic multiplexing. In a first: (a) the eMBB UEs to do the job and resources are pre-allocated to URLLC UEs which access these resources without UL grant, eMBB UEs have to avoid interfering the URLLC UEs by following the indication from the gNB. This is illustrated in figure 5. In a second (b) the URLLC UEs to do the job and resources are dynamically scheduled to both URLLC UEs and eMBB UEs, i.e., UL multiplexing is supported by not differentiating the UE type.

For many reasons none of the proposed enhancements address the outstanding issues and problems. The problems that are addressed by the present invention are thus in general to seek a solution to some or all of the problems in this domain. In particular, the invention seeks to address at least one of the following problems: increased eMBB UEs power consumption; increased control signalling overhead; impacted reliability for some packets when the corresponding transmissions do not have enough repetitions due to the random packet arrival moments; and any increased inter-cell interference when a URLLC UE uses a boosted output power when it is located in the cell edge area.

The present invention is accordingly seeking to solve at least some of the outstanding problems in this domain.

Summary

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

According to a first aspect of the present invention there is provided a method for enabling a wireless communication device to access services provided by a Radio Access Network between a base station BS and user equipment UE in which transmissions of one packet crosses multiple resource occasions, the method comprising at least one of: repeating a transport block before it is buffered; repeating the transmission of a buffered transport block a predetermined number of times, until the packet is successfully decoded.

Preferably, the step of repeating the transmission occurs during the period for transmission of the transport block.

Preferably, the step of repeating the transmission occurs at a bundle level and a bundle is a set of transmission occasions configured by an upper layer

Preferably, the step of repeating comprises at least one of: configuring the repetition at the BS; configuring the repetition at the UE; configuring the repetition based on a power control level.

Preferably, the start or end or a repetition is marked by a flag.

Preferably, different Demodulation Reference Signal sequences are used for different flags.

Preferably, there is a mapping between a value of the flag and the Demodulation Reference Signal sequence.

Preferably, the mapping is configures by the BS.

Preferably, different flags are indicated by a separately encoded indicator.

Preferably, the separately encoded indicator is piggybacked with each transmission.

Preferably, the step of repeating a transport block comprises at least one of: configuring the repetition at the BS; configuring the repetition at the UE; configuring the repetition based on the number of remaining occasions in a bundle and a bundle is a set of transmission occasions configured by an upper layer.

Preferably, the Radio Access Network is a New Radio/5G network.

According to a second aspect of the present invention there is provided equipment to perform the method of another aspect of the present invention.

According to a third aspect of the present invention there is provided a non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform the method of another aspect of the present invention.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory.

Brief description of the drawings

Further details, aspects and embodiments of the invention will be described, by way of example only, with reference to the drawings. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. Like reference numerals have been included in the respective drawings to ease understanding.

Figure 1 is a simplified diagram showing grant based and grant free transmission.

Figure 2 is a simplified diagram showing transmission repetition.

Figure 3 is a simplified diagram showing packets in a number of HARQ processes.

Figure 4 is a graph of collision probability versus channel usage.

Figure 5 is a simplified diagram showing a potential enhancement.

Figure 6 is a simplified diagram showing an overlap of resources, according to an embodiment of the present invention.

Figure 7 is a simplified diagram showing transmission of one packet crossing resources, according to an embodiment of the present invention.

Figure 8 is a simplified diagram showing a starting flag, according to an embodiment of the present invention.

Figure 9 is a simplified diagram showing TB repetition, according to an embodiment of the present invention.

Figure 10 is a simplified diagram showing the effects of TB repetition, according to an embodiment of the present invention.

Detailed description of the preferred embodiments

Those skilled in the art will recognise and appreciate that the specifics of the examples described are merely illustrative of some embodiments and that the teachings set forth herein are applicable in a variety of alternative settings.

The present invention relates to the wireless communication systems and more specifically, to a method and system to support UL multiplexing by bundle repetition and additionally power control.

This invention discloses a method to support UL multiplexing with different transmission durations. For transmissions with short duration, a set of resources are pre-allocated, UEs access the resources without UL grant and the transmission can be repeated for K times where K is upper layer configurable. Transmissions with long duration can be scheduled on resources fully or partially overlapping with resources pre-allocated to transmissions with short duration. Transmissions with short duration can be transmitted with bundle repetition and/or power control. One or more parameters for bundle repetition can be indicated by the gNB or selected by the UE.

As illustrated in figure 6, resource for a URLLC UE and resource for an eMBB UE may overlap each other. As a result, transmission of the eMBB UE may fail but it can be recovered with HARQ retransmission while transmission of the URLLC UE is expected to have a very high reliability and at least one of two following enhancements can be considered, i.e., boosted power and more repetitions.

As is known, boosted power may cause severe inter-cell interference so it can only be used when the UE is close to the gNB. Further repetitions can be considered when boosted power cannot be used. Relevant parameters, i.e., how many bundles to repeat, can be obtained in two possible ways, one is for the UE to determine based on DL measurement and the other is for the gNB to indicate based on UL measurement and/or DL measurement report.

For the UE determination, there are at least two parameters that can be considered, one is the signal strength of the serving cell which can be used to estimate the distance from the UE to the gNB. This is not always accurate, as the signal strength could be weak when the UE is close to the gNB but inside a building or the signal strength could be strong when the UE is far from the gNB but has line of sight propagation path with the gNB. Another parameter is the signal strength difference between the serving cell and any neighbour cell. Normally the signal strength difference is small when the UE is close the cell edge area. Combining the two parameters, the following possible situations arise.

Table 1

		Signal strength of the serving cell
		Strong	Weak
Signal strength difference	Big	Area A	Area B
Small	Area C	Area D

With bundle repetition, in each short period P, a Transport Block (TB) can be transmitted repeatedly on occasions and in addition, all occasions in the period P as a bundle can be further repeated to improve the reliability. Referring to table 1, in area A, boost power and single bundle repetition can achieve the required reliability. In area B, boosted power and bundle repetition together can help to achieve the required reliability and when the configured number of repetitions of a bundle is insufficient the UE can consider repeating the bundle repetition. In areas C and D, power cannot be boosted and the UE can only use bundle repetition. Thresholds between different areas can be configured by the gNB.

For the gNB indication, the gNB can at least make the decision based on the UE reported DL measurement results and UL measurement results of Sounding Reference Signal (SRS) sent by the UE. Boosted power can be indicated in the normal power control procedure and the number of bundle repetition can be indicated via Radio Resource Control (RRC) reconfiguration procedure. Or, it is also possible to associate the number of bundle repetitions with the indicated power control level, and the UE can obtain the number of bundle repetitions from the indicated output power level. In principle, more bundle repetitions are required when a higher power is indicated. Or, it is also possible to indicate the number of bundle repetitions in the DCI. As already specified, two types of grant free transmission are supported, the first type is that all parameters are pre-configured and cannot be changed until the next configuration; the second type is that all parameters are pre-configured but some can be modified by the DCI. The said number of bundle repetitions can be included in the DCI of the second type of grant free transmission.

For the problem as illustrated in Figure 3, the present invention provides the configurations as shown in Figure 7. The bundle size (i.e., period P) is reduced to 2 OFDM symbols, but the transmission can be repeated 3 times on a bundle level so in total, a packet can be transmitted 3 times maximum which is same as the best case of the specified solution. Compared with the specified solution as shown in Figure 3, the invention as shown in Figure 7 has a higher reliability for packet #1. As mentioned above, the number of bundle level repetitions can be either indicated by the gNB or determined by the UE.

As can be seen in figure 7, transmissions of one packet crossing the resources of multiple HARQ processes and this confuses the gNB when determining the HARQ process for each received packet. In addition, there is a risk for the gNB to combine different packets’ transmissions in the same soft combining. The HARQ process is essentially a control signalling process which is a combination of high-rate forward error-correcting coding and ARQ error-control.

A “stopping flag” can be introduced; it is transmitted together with the URLLC packet and can be obtained before channel decoding. “1” indicates this is not the final bundle and “0” indicates this is the final bundle. With the flag received, the gNB can merge all 3 received transmissions before the one (included) with flag value “0”. It is assumed that the gNB knows the number of bundle repetitions (3 in this example) in the case it was configured by the gNB otherwise the gNB can merge all received transmissions backward in time until either the last bundle (not included) with flag value “0” or with no DMRS detected whichever comes last. Additionally, the gNB can obtain the HARQ process ID from the bundle with flag value “0” in the same way as specified, i.e., the HARQ process ID is determined by the time domain position of the bundle with flag value “0”. It is understood that the method is similar to obtain the HARQ process ID from the first bundle of the same packet as the gNB is aware of the total number of bundle repetitions.

Alternatively, a “starting flag” can be used, and different from the example in Figure 7, this may be indicated as shown in Figure 8. “1” indicates this is the first bundle while “0” indicates this is NOT the first bundle. The gNB will try to detect the bundle with “flag=1 ”, optionally it can try to decode this bundle, and if it is unsuccessful, the gNB can make another try by merging the next bundle with “flag=0”; this procedure can be repeated until any of the following occur:

• The packet is successfully decoded;

• No bundle detected with DMRS detection (i.e., no signal received);

• A bundle of the same UE is detected with “flag=1” (i.e., a new packet).

As in the existing standards, the HARQ process ID can be obtained from the starting bundle (flag=1) position in time domain, for instance, the starting bundle of packet #1 is transmitted in an occasion associated with HARQ process #0 as shown in Figure 7 so packet #1 belongs to HARQ process #0.

One way to indicate the flag is to use different Demodulation Reference Signal (DMRS) sequences as shown in figure 8, one sequence is used to indicate value “1” and the other is used to indicate value “0” and at the gNB side, the DMRS sequence is blindly detected. This means when the connection is setup with a URLLC UE, the gNB can configure two sequences to the UE and either sequence can be used as UE identification.

Other than to use DMRS sequence to indicate the flag, it can also be indicated by a 1 -bit indicator which is separately encoded and piggybacked with the URLLC data transmission.

Optionally, TB repetition can be used with or without bundle repetition and TB repetition is explained with Figure 9. When a packet is received, it is prepared as a transport block (TB) which is then repeated a few times and finally all TBs (including repeated TBs) of all packets are stored into buffers of multiple HARQ processes. The buffered TBs are transmitted in either specified way when bundle repetition is not configured or in the proposed way above when bundle repetition is configured. The number of repetitions of a TB can be configured by the gNB or determined by the UE in the same way as that of bundle repetition.

It is not precluded that the numbers of repetitions of different TBs could be different and even associated with individual conditions. For example, a certain number of repetitions could only be trigger by the time of packet arrival, the TB could be repeated if the number of remaining occasions from the packet arrival to the end of period P (processing time excluded) is less than a pre-defined threshold otherwise no or less repetition(s).

Referring to figure 10, if we assume the number of TB repetitions is 2, we have the following results with the same example as shown in Figure 3. Compared with Figure 3, latency is slightly increased but the reliability problem is solved. When a packet is received successfully more than once, L2 of the receiver will keep one packet and discard all duplicated others.

An outcome of the present invention is that a number of advantages are provided. These include, but are not limited to the following. The eMBB UEs are not required to monitor DL in mini-slot level thus avoiding increasing UE power consumption. The eMBB UEs can transmit with normal power so the spectrum efficiency can be improved. The need to boost the output power in cell edge area so inter-cell interference is not increased is thus avoided. The URLLC UEs can transmit with bundle repetition so the required reliability can be achieved. Clearly other advantages are provided these are merely shown as examples.

The present invention can apply to other technical situations in which the same or similar problems are encountered and in which the above described solutions will apply. These include for example UCI (Uplink Control information) with extra reliability requirement.....

Although not shown in detail any of the devices or apparatus that form part of the network may include at least a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method of any aspect of the present invention. Further options and choices are described below.

The signal processing functionality of the embodiments of the invention especially the gNB and the UE may be achieved using computing systems or architectures known to those who are skilled in the relevant art. Computing systems such as, a desktop, laptop or notebook computer, hand-held computing device (PDA, cell phone, palmtop, etc.), mainframe, server, client, or any other type of special or general purpose computing device as may be desirable or appropriate for a given application or environment can be used. The computing system can include one or more processors which can be implemented using a general or special-purpose processing engine such as, for example, a microprocessor, microcontroller or other control module.

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

The computing system may also include an information storage system which may include, for example, a media drive and a removable storage interface. The media drive may include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a compact disc (CD) or digital video drive (DVD) read or write drive (R or RW), or other removable or fixed media drive. Storage media may include, for example, a hard disk, floppy disk, magnetic tape, optical disk, CD or DVD, or other fixed or removable medium that is read by and written to by media drive. The storage media may include a computer-readable storage medium having particular computer software or data stored therein.

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

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

In this document, the terms ‘computer program product’, ‘computer-readable medium’ and the like may be used generally to refer to tangible media such as, for example, a memory, storage device, or storage unit. These and other forms of computer-readable media may store one or more instructions for use by the processor comprising the computer system to cause the processor to perform specified operations. Such instructions, generally referred to as ‘computer program code’ (which may be grouped in the form of computer programs or other groupings), when executed, enable the computing system to perform functions of embodiments of the present invention. Note that the code may directly cause a processor to perform specified operations, be compiled to do so, and/or be combined with other software, hardware, and/or firmware elements (e.g., libraries for performing standard functions) to do so.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory

In an embodiment where the elements are implemented using software, the software may be stored in a computer-readable medium and loaded into computing system using, for example, removable storage drive. A control module (in this example, software instructions or executable computer program code), when executed by the processor in the computer system, causes a processor to perform the functions of the invention as described herein.

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

It will be appreciated that, for clarity purposes, the above description has described embodiments of the invention with reference to a single processing logic. However, the inventive concept may equally be implemented by way of a plurality of different functional units and processors to provide the signal processing functionality. Thus, references to specific functional units are only to be seen as references to suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organisation.

Aspects of the invention may be implemented in any suitable form including hardware, software, firmware or any combination of these. The invention may optionally be implemented, at least partly, as computer software running on one or more data processors and/or digital signal processors or configurable module components such as FPGA devices. Thus, the elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognize that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ does not exclude the presence of other elements or steps.

Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by, for example, a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. Also, the inclusion of a feature in one category of claims does not imply a limitation to this category, but rather indicates that the feature is equally applicable to other claim categories, as appropriate.

Furthermore, the order of features in the claims does not imply any specific order in which the features must be performed and in particular the order of individual steps in a method claim does not imply that the steps must be performed in this order. Rather, the steps may be performed in any suitable order. In addition, singular references do not exclude a plurality. Thus, references to ‘a’, ‘an’, ‘first’, ‘second’, etc. do not preclude a plurality.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognise that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ or “including” does not exclude the presence of other elements.

Claims

1. A method for enabling a wireless communication device to access services provided by a Radio Access Network between a base station BS and user equipment UE in which transmissions of one packet crosses multiple resource occasions, the method comprising at least one of: repeating a transport block before it is buffered; repeating the transmission of a buffered transport block a predetermined number of times, until the packet is successfully decoded.

2. The method of claim 1, wherein the step of repeating the transmission occurs during the period for transmission of the transport block.

3. The method of claim 1 or claim 2, wherein the step of repeating the transmission occurs at a bundle level and a bundle is a set of transmission occasions configured by an upper layer

4. The method of any preceding claim, wherein the step of repeating comprises at least one of: configuring the repetition at the BS; configuring the repetition at the UE; configuring the repetition based on a power control level.

5. The method of any preceding claim, wherein the start or end or a repetition is marked by a flag.

6. The method of claim 5, wherein different Demodulation Reference Signal sequences are used for different flags.

7. The method of claim 6, wherein there is a mapping between a value of the flag and the Demodulation Reference Signal sequence.

8. The method of claim 7, wherein the mapping is configures by the BS.

9. The method of any of claim 5 to 8, wherein different flags are indicated by a separately encoded indicator.

10. The method of claim 9, wherein the separately encoded indicator is piggybacked with each transmission.

11. The method of any preceding claim, wherein the step of repeating a transport block comprises at least one of: configuring the repetition at the BS; configuring the repetition at the UE; configuring the repetition based on the number of remaining occasions in a bundle and a bundle is a set of

5 transmission occasions configured by an upper layer.

12. The method of any preceding claims, wherein the Radio Access Network is a New Radio/5G network.

13. A device such as a UE or a BS, comprising a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and

10 communications interface are configured to perform the method as claimed in any one of claims 1 -12.

14. A non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform the method according to any of claims 1-12.