CN112585928B

CN112585928B - HARQ feedback transmission

Info

Publication number: CN112585928B
Application number: CN201880096459.2A
Authority: CN
Inventors: 骆喆; 陶涛; 刘建国; 武卓; 孟艳; 沈钢
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Current assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Priority date: 2018-08-09
Filing date: 2018-08-09
Publication date: 2023-10-27
Anticipated expiration: 2038-08-09
Also published as: TWI727385B; WO2020029189A1; CN112585928A; TW202015369A

Abstract

Embodiments of the present disclosure relate to a method, apparatus, and computer readable medium for HARQ feedback transmission. In an example embodiment, the method includes grouping, at a network device, a plurality of HARQ processes for a terminal device into at least one HARQ group; and in response to a failure to receive HARQ feedback for a HARQ process in the at least one HARQ group, transmitting to the terminal device first signaling for triggering transmission of the HARQ feedback, the first signaling comprising an indication for the at least one HARQ group.

Description

HARQ feedback transmission

Technical Field

Embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly, to a method, apparatus, and computer readable medium for hybrid automatic repeat request (HARQ) feedback transmission.

Background

In telecommunication networks such as those based on the third generation partnership project (3 GPP) specifications, HARQ mechanisms are employed. In the HARQ mechanism, the receiver detects whether there is an error in a packet received from the transmitter. If no error is detected in the received packet, the receiver will transmit a positive Acknowledgement (ACK) to the transmitter. On the other hand, if an uncorrectable error is detected in the received packet, the receiver will transmit a Negative Acknowledgement (NACK) to the transmitter. In response to the NACK, the transmitter retransmits the dropped packet. The ACK and NACK may be collectively referred to as HARQ feedback.

In a New Radio (NR) access network operating on an unlicensed spectrum, also called NR-U, a terminal device detects whether a slot is free or busy before it starts transmitting HARQ feedback to the network device in the slot, which is called a Listen Before Talk (LBT) procedure. If the LBT procedure fails, the terminal device may not be able to transmit HARQ feedback to the network device in that slot. Thus, HARQ feedback transmission opportunities are reduced due to LBT procedure failure.

Disclosure of Invention

In general, example embodiments of the present disclosure provide a method, apparatus, and computer-readable medium for HARQ feedback transmission.

In a first aspect, a method of communication is provided. The method comprises the following steps: at the network device, a plurality of hybrid automatic repeat request, HARQ, processes for the terminal device are grouped into at least one HARQ group. The method further comprises the steps of: in response to a failure to receive HARQ feedback for a HARQ process in at least one HARQ group, transmitting to the terminal device first signaling for triggering transmission of the HARQ feedback, the first signaling comprising an indication for the at least one HARQ group.

In some embodiments, grouping the plurality of HARQ processes comprises: determining a first timing indicator for a first HARQ process of the plurality of HARQ processes and a second timing indicator for a second HARQ process of the plurality of HARQ processes; determining whether the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity based on the first timing indicator and the second timing indicator; and in response to determining that the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity, grouping the first HARQ process and the second HARQ process into a first HARQ group.

In some embodiments, grouping the plurality of HARQ processes comprises: determining whether a first downlink grant associated with a third HARQ process of the plurality of HARQ processes and a second downlink grant associated with a fourth HARQ process of the plurality of HARQ processes are transmitted in a single set of control resources; and in response to determining that the first downlink grant and the second downlink grant are transmitted in a single set of control resources, grouping the third HARQ process and the fourth HARQ process into a second HARQ group of the at least one HARQ group.

In some embodiments, the indication for the at least one HARQ group comprises at least one of: an identification of at least one HARQ group, and a bitmap, the bits in the bitmap being associated with the at least one HARQ group.

In some embodiments, the method further comprises: transmitting to the terminal device second signaling for scheduling downlink transmissions, the second signaling comprising: an identification of a fifth HARQ process of the plurality of HARQ processes, the fifth HARQ process associated with the downlink transmission, and an indication of a HARQ group to which the fifth HARQ process is grouped.

In some embodiments, the method further comprises: transmitting to the terminal device third signaling for scheduling another downlink transmission, the third signaling comprising: an identification of a sixth HARQ process of the plurality of HARQ processes, the sixth HARQ process associated with another downlink transmission, and an index of the sixth HARQ process in another HARQ group, the sixth HARQ process being grouped into the other HARQ group.

In some embodiments, transmitting the first signaling includes: in response to a failure to receive HARQ feedback for the sixth HARQ process, transmitting first signaling comprising an indication for another HARQ group and another bitmap, bits in the other bitmap being associated with an index for the sixth HARQ process.

In a second aspect, a communication method is provided. The method comprises the following steps: a first signaling is received from a network device, the first signaling for triggering transmission of at least one HARQ feedback for at least one hybrid automatic repeat request, HARQ, process, the first signaling comprising an indication for at least one HARQ group. The method further comprises the steps of: a determination is made as to whether one or more HARQ groups to which at least one HARQ process is to be grouped are indicated. The method further comprises the steps of: in response to determining that the indication indicates one or more HARQ groups, HARQ feedback is transmitted to the network device.

In some embodiments, the method further comprises: receiving, from the network device, second signaling for scheduling downlink transmissions, the second signaling comprising: an identification of a HARQ process of the at least one HARQ process, a fifth HARQ process associated with the downlink transmission, and an indication of the HARQ group to which the HARQ process is grouped.

In some embodiments, determining whether the indication indicates one or more HARQ groups comprises: it is determined whether the indication for at least one HARQ group in the first signaling is the same as the indication for the HARQ group.

In some embodiments, determining whether the indication indicates one or more HARQ groups comprises: determining an initial HARQ feedback transmission occasion for a second HARQ process of the at least one HARQ process based on a timing indicator received from the network device for the second HARQ process; determining an HARQ group to which the second HARQ process is grouped based on the initial HARQ feedback transmission opportunity; and determining whether the indication for the at least one HARQ group in the first signaling indicates a HARQ group.

In some embodiments, determining whether the indication indicates one or more HARQ groups comprises: determining, based on the set of control resources, a HARQ group to which a third HARQ process of the at least one HARQ process is grouped, a downlink grant associated with the third HARQ process being transmitted on the set of control resources; and determining whether the indication for the at least one HARQ group in the first signaling indicates a HARQ group.

In some embodiments, the method further comprises: receiving third signaling from the network device for scheduling another downlink transmission, the third signaling comprising: an identification of a fourth HARQ process of the at least one HARQ process, the fourth HARQ process being associated with another downlink transmission, and an index of the fourth HARQ process in another HARQ group, the fourth HARQ process being grouped into the other HARQ group.

In some embodiments, receiving the first signaling comprises: first signaling is received that includes an indication for another HARQ group and another bitmap, bits in the other bitmap being associated with an index of a fourth HARQ process.

In a third aspect, a network device is provided. The network device includes: at least one processor; and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform the method according to the first aspect.

In a fourth aspect, a terminal device is provided. The terminal device includes: at least one processor; and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform the method according to the second aspect.

In a fifth aspect, a computer readable medium is provided on which a computer program is stored. The computer program, when executed by a processor, causes the processor to perform the method according to the first aspect.

In a sixth aspect, a computer readable medium is provided on which a computer program is stored. The computer program, when executed by a processor, causes the processor to perform the method according to the second aspect.

It should be understood that the summary is not intended to identify key or essential features of the embodiments of the disclosure, nor is it intended to be used to limit the scope of the disclosure. Other features of the present disclosure will become apparent from the description that follows.

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent from the following more detailed description of some embodiments thereof in the accompanying drawings in which:

FIG. 1 illustrates an example communication network in which embodiments of the present disclosure may be implemented;

fig. 2 is a signaling diagram of an example process for HARQ feedback transmission, according to some embodiments of the present disclosure;

fig. 3 is a flow chart of a HARQ feedback transmission method according to some embodiments of the present disclosure;

fig. 4 is a flow chart of a HARQ feedback transmission method according to some embodiments of the present disclosure;

fig. 5 is a block diagram of an apparatus suitable for implementing embodiments of the present disclosure.

The same or similar reference numbers will be used throughout the drawings to refer to the same or like elements.

Detailed Description

Principles of the present disclosure will now be described with reference to some example embodiments. It should be understood that these embodiments are described for illustrative purposes only and to assist those skilled in the art in understanding and practicing the present disclosure without implying any limitation on the scope of the present disclosure. The disclosure described herein may be implemented in various ways other than those described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

As used herein, the term "communication network" refers to a network that conforms to any suitable communication standard or protocol, such as Long Term Evolution (LTE), LTE-advanced (LTE-a), and 5G NR, and employs any suitable communication technology including, for example, MIMO, OFDM, time Division Multiplexing (TDM), frequency Division Multiplexing (FDM), code Division Multiplexing (CDM), bluetooth, zigBee, machine Type Communication (MTC), embbc, mctc, and ul lc technologies. For discussion purposes, in some embodiments, an LTE network, an LTE-a network, a 5G NR network, or any combination thereof is taken as an example of a communication network.

As used herein, the term "network device" refers to any suitable device on the network side of a communication network. The network devices may include any suitable devices in an access network of a communication network, including, for example, base Stations (BSs), repeaters, access Points (APs), node BS (nodebs or NB), evolved node BS (eNodeB or eNB), gigabit NodeB (gNB), remote radio modules (RRU), radio Heads (RH), remote Radio Heads (RRH), low power nodes such as femto, pico, etc. For discussion purposes, in some embodiments, an eNB is taken as an example of a network device.

The network devices may also include any suitable devices in the core network, including, for example, multi-standard radio (MSR) radio devices such as MSR BS, network controllers such as Radio Network Controllers (RNC) or Base Station Controllers (BSC), multi-cell/Multicast Coordination Entities (MCEs), mobile Switching Centers (MSCS) and MMEs, operations and management (O & M) nodes, operations Support System (OSS) nodes, self-organizing network (SON) nodes, location nodes such as enhanced services mobile location centers (E-SMLCs), and/or Mobile Data Terminals (MDTs).

As used herein, the term "terminal device" refers to a device that is capable of, configured, arranged and/or operable to communicate with a network device or other terminal devices in a communication network. Communication may involve the transmission and/or reception of wireless signals using electromagnetic signals, radio waves, infrared signals, and/or other types of signals suitable for conveying information over the air. In some embodiments, the terminal device may be configured to transmit and/or receive information without direct human interaction. For example, the terminal device may transmit information to the network device according to a predetermined schedule when triggered by an internal or external event, or in response to a request from the network side.

Examples of terminal devices include, but are not limited to, user Equipment (UE) such as smart phones, wireless enabled tablet computers, laptop embedded devices (LEs), laptop installed devices (LMEs), and/or wireless Customer Premise Equipment (CPE). For discussion purposes, some embodiments will be described below with reference to a UE as an example of a terminal device, and the terms "terminal device" and "user equipment" (UE) may be used interchangeably in the context of the present disclosure.

As used herein, the term "cell" refers to the area covered by radio signals transmitted by a network device. Terminal devices within a cell may be served by a network device and access a communication network via the network device.

As used herein, the term "circuitry" may refer to one or more or all of the following: (a) Hardware-only circuit implementations (such as implementations in analog and/or digital circuits only); and (b) a combination of hardware circuitry and software, for example (if applicable): (i) A combination of analog and/or digital hardware circuit(s) and software/firmware, and (ii) any portion of a hardware processor(s) (including digital signal processor (s)), software, and memory(s) with software that work together to cause a device, such as a mobile phone or server, to perform various functions; and (c) hardware circuit(s) and/or processor(s), such as microprocessor(s) or portion of microprocessor(s), that require software (e.g., firmware) to operate, but when software is not required for operation, the software may not be present.

This definition of circuit applies to all uses of this term in this application (including in any claims). As another example used in this disclosure, the term circuitry also encompasses implementations of only a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also encompasses, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a server, a cellular network device, or other similar integrated circuit in a computing or network device.

As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term "comprising" and variants thereof is to be construed as open-ended terms, meaning "including, but not limited to. The term "based on" is to be understood as "based at least in part on". The terms "one embodiment" and "an embodiment" will be understood as "at least one embodiment". The term "another embodiment" will be understood to mean "at least one other embodiment". Other explicit and implicit definitions may be included below.

Fig. 1 illustrates an example communication network 100 in which embodiments of the present disclosure may be implemented. The network 100 includes a network device 110 and a terminal device 120 served by the network device 110. The service area of network device 110 is referred to as cell 102. It should be understood that the number of network devices and terminal devices is for illustration purposes only and does not imply any limitation. Network 100 may include any suitable number of network devices and terminal devices suitable for implementing embodiments of the present disclosure. Although not shown, it is to be appreciated that one or more terminal devices can be located in cell 102 and served by network device 110.

Communications in network 100 may conform to any suitable standard including, but not limited to, global system for mobile communications (GSM), global system for mobile communications extended coverage (EC-GSM-IoT), long Term Evolution (LTE), LTE-evolution, LTE-advanced (LTE-a), wideband Code Division Multiple Access (WCDMA), code Division Multiple Access (CDMA), GSM EDGE Radio Access Network (GERAN), and the like. Furthermore, the communication may be performed according to any generation communication protocol currently known or to be developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G) communication protocols.

In the communication network 100, the network device 110 may transmit data and control information to the terminal device 120, and the terminal device 120 may also transmit data and control information to the network device 110. The link from network device 110 to terminal device 120 is referred to as the Downlink (DL), and the link from terminal device 120 to network device 110 is referred to as the Uplink (UL).

For NR, the HARQ feedback transmission opportunity for a Physical Downlink Shared Channel (PDSCH) is determined based on the PDSCH-to-HARQ feedback timing indicator given in the corresponding DL grant. The terminal device will report feedback for one or more DL HARQ processes at a feedback transmission opportunity determined based on the PDSCH-to-HARQ feedback timing indicator. However, on unlicensed spectrum, HARQ feedback transmissions may be blocked due to LBT process failure. The NR does not provide additional feedback transmission opportunities for those feedback transmission opportunities that are blocked.

For MuLTEFire 1.X, in order to handle blocked HARQ feedback transmissions for PDSCH, a mechanism is proposed to report feedback of all DL HARQ processes via a short physical uplink control channel (sPUCCH) or an extended physical uplink control channel (ePUCCH) by triggering. Since HARQ feedback is reported for many unused DL HARQ processes, the main problem of this mechanism is high overhead if the number of all DL HARQ processes is large or Code Block Group (CBG) based transmission is used.

It is also proposed to transmit HARQ feedback for all DL HARQ processes transmitted in slot #n-4 or earlier in the same transmission opportunity (TxOP) as well as HARQ feedback not yet transmitted in the previous TxOP (because the initial feedback report is blocked or there is not enough processing time). If the network device misses the feedback report, the main problem of this scheme is misunderstanding between the terminal device and the network device.

To address at least some of the above problems and other potential problems, in accordance with embodiments of the present disclosure, a solution for dynamic group-based HARQ feedback transmission is presented. In this solution, the network device groups a plurality of HARQ processes for the terminal device into at least one HARQ group. Each HARQ group is assigned an indication for that group. If the network device fails to receive HARQ feedback for one or more HARQ processes in one or more HARQ groups, the network device transmits signaling to the terminal device for triggering transmission of the HARQ feedback. The signaling includes an indication of one or more HARQ groups.

With this solution, in response to a trigger from the network device, the terminal device may transmit HARQ feedback for HARQ processes in one or more HARQ groups indicated by the network device, instead of transmitting HARQ feedback for all configured HARQ processes. Thus, feedback overhead may be reduced. Furthermore, since the network device provides an explicit indication for one or more HARQ groups, misunderstandings between the network device and the terminal device can be avoided.

The principles and implementations of the present disclosure will be described in detail below with reference to fig. 2, fig. 2 showing a process 200 for HARQ feedback transmission according to an embodiment of the present disclosure. For discussion purposes, process 200 will be described with reference to FIG. 1. Process 200 may relate to network device 110 and terminal device 120 in fig. 1.

Network device 110 groups (210) the plurality of HARQ processes for terminal device 120 into at least one HARQ group.

In some embodiments, for packet purposes, network device 110 determines a first timing indicator for a first HARQ process of the plurality of HARQ processes and a second timing indicator for a second HARQ process of the plurality of HARQ processes. The timing indicator for the HARQ process may indicate a time from receiving the DL transmission to transmitting initial HARQ feedback for the HARQ process associated with the DL transmission. Based on the first timing indicator and the second timing indicator, network device 110 may determine whether the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity. Examples of timing indicators include, but are not limited to, PDSCH-to-HARQ feedback timing indicators.

Consider an example in which network device 110 transmits a first DL transmission at slot #0, a second DL transmission at slot #1, a third DL transmission at slot #3, and a fourth DL transmission at slot # 4. The first DL transmission is associated with a first HARQ process having an Identification (ID) of 6 (also referred to as first HARQ process # 6). The second DL transmission is associated with a second HARQ process having an ID of 3 (also referred to as second HARQ process # 3). The third DL transmission is associated with a third HARQ process having an ID of 2 (also referred to as third HARQ process # 2). The fourth DL transmission is associated with a fourth HARQ process having an ID of 9 (also referred to as fourth HARQ process # 9).

The PDSCH-to-HARQ feedback timing indicator for the first HARQ process #6 indicates 5 slots from receiving the first DL transmission to transmitting the initial HARQ feedback for the first HARQ process # 6. The PDSCH-to-HARQ feedback timing indicator for the second HARQ process #3 indicates 4 slots from receiving the second DL transmission to transmitting the initial HARQ feedback for the second HARQ process # 3. The PDSCH-to-HARQ feedback timing indicator for the third HARQ process #2 indicates 4 slots from receiving the third DL transmission to transmitting the initial HARQ feedback for the third HARQ process # 2. The PDSCH-to-HARQ feedback timing indicator for the fourth HARQ process #9 indicates 3 slots from receiving the fourth DL transmission to transmitting the initial HARQ feedback for the fourth HARQ process # 9.

The network device 110 determines an initial HARQ feedback transmission occasion for the HARQ feedback of the first HARQ process #6 as slot #5. The network device 110 determines an initial HARQ feedback transmission occasion for the HARQ feedback of the second HARQ process #3 as slot #5. Thus, network device 110 may determine that first HARQ process #6 and second HARQ process #3 share the same initial HARQ feedback transmission occasion at slot #5. Thus, network device 110 groups first HARQ process #6 and second HARQ process #3 into a first HARQ group. In the case where the total number of all HARQ groups is four, the network device 110 may determine the ID for the first HARQ group to be #1 (i.e., 5 modulo 4).

The network device 110 determines an initial HARQ feedback transmission occasion for the HARQ feedback of the third HARQ process #2 as slot #7. The network device 110 determines the initial HARQ feedback transmission occasion for the HARQ feedback of the fourth HARQ process #9 as slot #7. Thus, network device 110 may determine that third HARQ process #2 and fourth HARQ process #9 share the same initial HARQ feedback transmission occasion at slot #7. Thus, network device 110 groups third HARQ process #2 and fourth HARQ process #9 into a second HARQ group. In the case where the total number of all HARQ groups is four, the network device 110 may determine the ID for the second HARQ group to be #3 (i.e., 7 modulo 4).

In some embodiments, for packet purposes, network device 110 determines whether to transmit a first DL grant associated with a fifth HARQ process of the plurality of HARQ processes and a second DL grant associated with a sixth HARQ process of the plurality of HARQ processes in a single control resource set (CORSET). For example, if both the first DL grant and the second DL grant are transmitted in the CORSET of slot #0, the network device 110 may determine that the first DL grant and the second DL grant are transmitted in a single (same) CORSET. Thus, network device 110 may group the fifth HARQ process and the sixth HARQ process into a third HARQ group.

It should be understood that packets according to the present disclosure are dynamic packets, which vary with scheduling. Dynamic grouping avoids inefficiency of static grouping.

With continued reference to fig. 2, if the network device 110 fails to receive HARQ feedback for HARQ processes in at least one HARQ group, the network device 110 transmits (220) first signaling to the terminal device 120 for triggering HARQ feedback transmission. The first signaling includes an indication for at least one HARQ group. Since the first signaling for triggering includes an indication for at least one HARQ group instead of an explicit identification for the triggered HARQ process, overhead for triggering may be reduced.

Accordingly, the terminal device 120 receives the first signaling for triggering HARQ feedback transmission.

In some embodiments, the indication for the at least one HARQ group in the first signaling for triggering may include an identification of the at least one HARQ group.

In other embodiments, the indication for the at least one HARQ group in the first signaling for triggering comprises a bitmap. Bits in the bitmap are associated with at least one HARQ group. For example, a first bit in the bitmap may be associated with a first HARQ group #1 and a second bit in the bitmap may be associated with a second HARQ group # 3. If the bit in the bitmap is set to 1, HARQ feedback for the HARQ process in the associated HARQ group is indicated to be triggered for transmission. If the bit in the bitmap is set to 0, it indicates that HARQ feedback for the HARQ processes in the associated HARQ group is not triggered for transmission.

In some embodiments, the first signaling for triggering may include Downlink Control Information (DCI) for UL grant of a Physical Uplink Control Channel (PUCCH) of Uplink Control Information (UCI) of HARQ feedback. For example, in the case of using an identification of a HARQ group to indicate the triggered group, the DCI may include the following: the triggered HARQ group ID (2 bits) and PUCCH resource indicator (3 bits). For another example, in the case where a bitmap is used to indicate one or more trigger groups, the DCI may include the following: the triggered HARQ group bitmap (4 bits) and PUCCH resource indicator (3 bits).

In some embodiments, network device 110 may trigger transmission of HARQ feedback for HARQ processes in more than one HARQ group. In some such embodiments, the network device 110 may transmit first signaling for triggering to the terminal device 120, the first signaling including a bitmap for more than one HARQ group. For example, the first signaling for triggering may include a bitmap 0101 indicating that the first HARQ group #1 and the second HARQ group #3 are to be triggered.

In some embodiments, network device 110 may trigger transmission of HARQ feedback for a portion of the HARQ processes in the HARQ group. In such embodiments, network device 110 may assign an index to each HARQ process in the HARQ group. The index may be different from the ID of the corresponding HARQ process. Before triggering transmission of HARQ feedback for a portion of the HARQ processes, network device 110 may transmit signaling to terminal device 120, the signaling including an ID of the HARQ process and an index of the HARQ process in the HARQ group. In some embodiments, the signaling may include DCI of one or more DL grants of a PDSCH for DL transmissions. For example, DL grant of PDSCH for DL transmission may include the following: HARQ process ID (3 bits), index of HARQ process (2 bits), downlink allocation index (2 bits), PDSCH-to-HARQ timing indicator (3 bits) and CBG transmission information (4 bits).

Consider an example in which network device 110 transmits three DL grants in the same CORSET for slot # 0. These three DL grants are used to schedule DL transmissions associated with HARQ processes #6, #3, and #10, respectively. HARQ processes #6, #3, and #10 may then be grouped into HARQ group #0 (0 modulo 4, where "0" represents slot #0 and the total number of all HARQ groups is four). Network device 110 may assign indexes #0, #1, and #2 to HARQ processes #6, #3, and # 10. If network device 110 fails to receive HARQ feedback for HARQ processes #6 and #10, network device 110 may transmit signaling to trigger HARQ feedback transmissions for HARQ processes #6 and # 10. In this case, the signaling for triggering may include an ID of the HARQ group (HARQ group # 0) and a bitmap. The bits in the bitmap are associated with the index of the triggered HARQ process. For example, the bitmap may be 1010 indicating that HARQ processes with indices #0 and #2 are to be triggered.

Returning to fig. 2, upon receiving the first signaling for triggering, the terminal device 120 determines (230) whether the indication in the first signaling indicates one or more HARQ groups to which at least one HARQ process is grouped.

In some embodiments, based on an explicit indication (e.g., an identification or bitmap) received from network device 110 for one or more HARQ groups, terminal device 120 determines whether the indication in the first signaling indicates one or more HARQ groups to which at least one HARQ process is grouped.

In some embodiments, the network device 110 transmits second signaling for scheduling DL transmissions to the terminal device 120 prior to the first signaling for triggering. The second signaling may include at least: an identification of a HARQ process associated with the DL transmission; and an indication of the HARQ group to which the HARQ process is grouped.

In some embodiments, the second signaling for scheduling DL transmissions may include DCI for DL grants of a PDSCH for DL transmissions. For example, DCI may include the following: HARQ group ID (2 bits), HARQ process ID (3 bits), downlink allocation index (2 bits), PDSCH-to-HARQ timing indicator (3 bits), code Block Group (CBG) transmission information (4 bits).

In embodiments where the second signaling for scheduling DL transmissions includes an identification of the HARQ process and an indication of the HARQ group to which the HARQ process is grouped, upon receiving the second signaling, the terminal device 120 may be aware that the HARQ process is grouped into the HARQ group indicated by the indication in the second signaling. Upon receiving the first signaling for triggering, the terminal device 120 may determine whether the indication for at least one HARQ group in the first signaling is the same as the indication for the HARQ group in the second signaling. If the terminal device 120 determines that the indication for at least one HARQ group in the first signaling is the same as the indication for the HARQ group in the second signaling, the terminal device 120 determines that the indication in the first signaling indicates one or more HARQ groups to which the at least one HARQ process is grouped.

In other embodiments, no explicit indication for one or more HARQ groups is received in the second signaling from network device 110. Instead, the terminal device 120 determines the identity of the HARQ group to which the HARQ process is grouped based on the initial HARQ feedback transmission occasion for the HARQ process.

For example, terminal device 120 may receive the PDSCH-to-HARQ timing indicator for the HARQ process in second signaling for scheduling DL transmissions associated with the HARQ process. The terminal device 120 may determine an initial HARQ feedback transmission occasion for the HARQ process based on the PDSCH-to-HARQ timing indicator. For example, based on the PDSCH-to-HARQ timing indicator, the terminal device 120 may determine the initial HARQ feedback transmission occasion for the HARQ process as slot #5. In case that the total number of all HARQ groups is four, the terminal device 120 may determine the identity of the HARQ group to be #1 (i.e., 5 modulo 4). The total number of all HARQ groups may be preconfigured or signaled by the network device 110.

In other embodiments, no explicit indication for one or more HARQ groups is received in the second signaling from network device 110. Instead, based on the CORSET in which the DL grant associated with the HARQ process is received, terminal device 120 determines the identity of the HARQ group to which the HARQ process is grouped. For example, if a DL grant is received in the CORSET of slot #0 and the total number of all HARQ groups is four, the terminal device 120 may determine the identity for the HARQ group as #0 (i.e., 0 modulo 4).

With continued reference to fig. 2, if the terminal device 120 determines that the indication in the first signaling indicates one or more HARQ groups, the terminal device 120 transmits (240) HARQ feedback to the network device 110.

In some embodiments, the signaling for triggering may include a PUCCH resource indicator indicating resources for transmitting one or more HARQ feedback.

In some embodiments, the signaling for scheduling DL transmissions may include a Downlink Allocation Index (DAI). The terminal device 120 may determine the position of the bits of the HARQ feedback based on the DAI.

In embodiments where HARQ feedback for more than one HARQ group is triggered, the terminal device 120 may determine the location of the bits of HARQ feedback for each triggered HARQ group based on the DAI received in the signaling for scheduling DL transmissions. The terminal device 120 may then transmit a concatenation of bits of HARQ feedback for each triggered HARQ group to the network device 110. For example, the bit of the HARQ feedback for HARQ group #1 is 1110|0110|1111 and the bit of the HARQ feedback for HARQ group #3 is 1111|1011. Terminal device 120 may transmit 1110|0110|1111 and 1111|1011 in series, i.e., 1110|0110|1111|1111|1011, to network device 110.

Fig. 3 is a flow chart of a method 300 for HARQ feedback transmission according to some embodiments of the present disclosure. For example, the method 300 may be implemented at the network device 110 as shown in fig. 1. It should be understood that method 300 may include additional blocks not shown and/or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this respect.

At block 310, network device 110 groups a plurality of HARQ processes for terminal device 120 into at least one HARQ group.

In response to failure to receive HARQ feedback for the HARQ processes in the at least one HARQ group, the network device 110 transmits first signaling to the terminal device 120 triggering HARQ feedback transmission, block 320. The first signaling includes an indication for at least one HARQ group.

In some embodiments, grouping the plurality of HARQ processes includes: determining a first timing indicator for a first HARQ process of the plurality of HARQ processes and a second timing indicator for a second HARQ process of the plurality of HARQ processes; determining whether the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity based on the first timing indicator and the second timing indicator; and in response to determining that the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity, grouping the first HARQ process and the second HARQ process into a first HARQ group.

In some embodiments, grouping the plurality of HARQ processes includes: determining whether to transmit a first downlink grant associated with a third HARQ process of the plurality of HARQ processes and a second downlink grant associated with a fourth HARQ process of the plurality of HARQ processes in a single set of control resources; and in response to determining to transmit the first downlink grant and the second downlink grant in a single set of control resources, grouping the third HARQ process and the fourth HARQ process into a second HARQ group of the at least one HARQ group.

In some embodiments, the method 300 further comprises: transmitting to the terminal device second signaling for scheduling downlink transmissions, the second signaling comprising: an identification of a fifth HARQ process of the plurality of HARQ processes, the fifth HARQ process associated with the downlink transmission, and an indication of a HARQ group to which the fifth HARQ process is grouped.

In some embodiments, the method 300 further comprises: transmitting to the terminal device third signaling for scheduling another downlink transmission, the third signaling comprising: an identification of a sixth HARQ process of the plurality of HARQ processes, the sixth HARQ process associated with the other downlink transmission, and an index of a sixth HARQ process of the other HARQ group to which the sixth HARQ process is grouped.

In some embodiments, transmitting the first signaling includes: in response to failure to receive HARQ feedback for the sixth HARQ process, transmitting first signaling comprising an indication for the further HARQ group and a further bitmap, bits in the further bitmap being associated with an index for the sixth HARQ process.

Fig. 4 is a flow chart of a method 400 for HARQ feedback transmission according to some embodiments of the present disclosure. For example, the method 400 may be implemented at the terminal device 120 as shown in fig. 1. It should be understood that method 400 may include additional blocks not shown and/or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this respect.

At block 410, terminal device 120 receives first signaling from network device 110 for triggering transmission of at least one HARQ feedback for at least one HARQ process. The first signaling includes an indication for at least one HARQ group.

At block 420, terminal device 120 determines whether the indication indicates one or more HARQ groups to which at least one HARQ process is grouped.

At block 430, if the terminal device 120 determines that the indication indicates one or more HARQ groups, the terminal device 120 transmits HARQ feedback to the network device 110.

In some embodiments, the indication for the at least one HARQ group comprises at least one of: an identification of the at least one HARQ group, and a bitmap, the bits in the bitmap being associated with the at least one HARQ group.

In some embodiments, the method 400 further comprises: receiving, from the network device, second signaling for scheduling downlink transmissions, the second signaling comprising: an identification of a HARQ process of the at least one HARQ process, a fifth HARQ process associated with the downlink transmission, and an indication of the HARQ group to which the HARQ process is grouped.

In some embodiments, determining whether the indication indicates one or more HARQ groups comprises: determining an initial HARQ feedback transmission occasion for a second HARQ process of the at least one HARQ process based on a timing indicator for the second HARQ process received from the network device; determining an HARQ group to which the second HARQ process is grouped based on the initial HARQ feedback transmission opportunity; and determining whether the indication for the at least one HARQ group in the first signaling indicates a HARQ group.

In some embodiments, determining whether the indication indicates one or more HARQ groups comprises: determining, based on the control resource set, a HARQ group to which a third HARQ process of the at least one HARQ process is grouped, a downlink grant associated with the third HARQ process transmitted on the control resource set; and determining whether the indication for the at least one HARQ group in the first signaling indicates a HARQ group.

In some embodiments, the method 400 further comprises: receiving third signaling from the network device for scheduling another downlink transmission, the third signaling comprising: an identification of a fourth HARQ process of the at least one HARQ process, the fourth HARQ process being associated with the further downlink transmission, and an index of the fourth HARQ process in a further HARQ group into which the fourth HARQ process is grouped.

In some embodiments, receiving the first signaling comprises: a first signaling is received, the first signaling comprising an indication for the further HARQ group and a further bitmap, bits in the further bitmap being associated with an index of a fourth HARQ process.

In some embodiments, an apparatus (e.g., network device 110) capable of performing method 300 may include means for performing the various steps of method 300. The apparatus may be implemented in any suitable form. For example, the apparatus may be implemented in a circuit or in a software module.

In some embodiments, the apparatus comprises: means for grouping a plurality of hybrid automatic repeat request (HARQ) processes for a terminal device into at least one HARQ group. The apparatus also includes means for transmitting, to the terminal device, first signaling for triggering HARQ feedback transmission in response to a HARQ feedback reception failure for a HARQ process in the at least one HARQ group, the first signaling comprising an indication for the at least one HARQ group.

In some embodiments, an apparatus for grouping a plurality of HARQ processes comprises: means for determining a first timing indicator for a first HARQ process of the plurality of HARQ processes and a second timing indicator for a second HARQ process of the plurality of HARQ processes; means for determining whether the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity based on the first timing indicator and the second timing indicator; and means for grouping the first HARQ process and the second HARQ process into a first HARQ group in response to determining that the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity.

In some embodiments, an apparatus for grouping a plurality of HARQ processes comprises: means for determining whether a first downlink grant associated with a third HARQ process of the plurality of HARQ processes and a second downlink grant associated with a fourth HARQ process of the plurality of HARQ processes are transmitted in a single set of control resources; and means for grouping the third HARQ process and the fourth HARQ process into a second HARQ group of the at least one HARQ group in response to determining that the first downlink grant and the second downlink grant are transmitted in a single set of control resources.

In some embodiments, the indication for the at least one HARQ group comprises at least one of: the identification of the at least one HARQ group, and a bitmap, the bits in the bitmap being associated with the at least one HARQ group.

In some embodiments, the apparatus further comprises: means for transmitting to the terminal device second signaling for scheduling downlink transmissions, the second signaling comprising: an identification of a fifth HARQ process of the plurality of HARQ processes, the fifth HARQ process associated with the downlink transmission, and an indication of a HARQ group to which the fifth HARQ process is grouped.

In some embodiments, the apparatus further comprises: means for transmitting to the terminal device third signaling for scheduling another downlink transmission, the third signaling comprising: an identification of a sixth HARQ process of the plurality of HARQ processes, the sixth HARQ process associated with the other downlink transmission, and an index in another HARQ group of the sixth HARQ process, the sixth HARQ process being grouped into the other HARQ group.

In some embodiments, the means for transmitting the first signaling comprises: means for transmitting, in response to a failure to receive HARQ feedback for the sixth HARQ process, first signaling comprising an indication for another HARQ group and another bitmap, bits in the other bitmap being associated with an index for the sixth HARQ process.

In some embodiments, an apparatus (e.g., terminal device 120) capable of performing method 400 may include means for performing the various steps of method 400. The apparatus may be implemented in any suitable form. For example, the apparatus may be implemented in a circuit or in a software module.

In some embodiments, the apparatus includes means for receiving, from a network device, first signaling to trigger transmission of at least one hybrid automatic repeat request (HARQ) feedback for at least one HARQ process, the first signaling including an indication for at least one HARQ group. The apparatus also includes means for determining whether the indication indicates one or more HARQ groups to which at least one HARQ process is grouped. The apparatus also includes means for transmitting HARQ feedback to the network device in response to determining that the indication indicates one or more HARQ groups.

In some embodiments, the indication for the at least one HARQ group comprises at least one of: an identification of at least one HARQ group and a bitmap, the bits in the bitmap being associated with the at least one HARQ group.

In some embodiments, the apparatus further comprises: means for receiving second signaling from the network device for scheduling downlink transmissions, the second signaling comprising: an identification of a HARQ process of the at least one HARQ process, a fifth HARQ process associated with the downlink transmission, and an indication of the HARQ group to which the HARQ process is grouped.

In some embodiments, the means for determining whether the indication indicates one or more HARQ groups comprises: means for determining whether the indication for at least one HARQ group in the first signaling is the same as the indication for the HARQ group.

In some embodiments, the means for determining whether the indication indicates one or more HARQ groups comprises: means for determining an initial HARQ feedback transmission occasion for a second HARQ process of the at least one HARQ process based on a timing indicator received from the network device for the second HARQ process; means for determining a HARQ group to which the second HARQ process is grouped based on the initial HARQ feedback transmission occasion; and means for determining whether the indication for the at least one HARQ group in the first signaling indicates a HARQ group.

In some embodiments, the means for determining whether the indication indicates one or more HARQ groups comprises: means for determining, based on the set of control resources, a HARQ group to which a third HARQ process of the at least one HARQ process is grouped, a downlink grant associated with the third HARQ process being transmitted on the set of control resources; and means for determining whether the indication for the at least one HARQ group in the first signaling indicates a HARQ group.

In some embodiments, the apparatus further comprises: means for receiving third signaling from the network device for scheduling another downlink transmission, the third signaling comprising: an identification of a fourth HARQ process of the at least one HARQ process, the fourth HARQ process being associated with the further downlink transmission, and an index of the fourth HARQ process in a further HARQ group into which the fourth HARQ process is grouped.

In some embodiments, the means for receiving the first signaling comprises: means for receiving a first signaling comprising an indication for another HARQ group and another bitmap, bits in the other bitmap being associated with an index of a fourth HARQ process.

Fig. 5 is a simplified block diagram of an apparatus 500 suitable for implementing embodiments of the present disclosure. Device 500 may be considered another example implementation of network device 101 as shown in fig. 1. Thus, device 500 may be implemented at network device 110 or terminal device 120, or as at least a portion of network device 110 or terminal device 120.

As shown, device 500 includes a processor 510, a memory 520 coupled to processor 510, suitable Transmitters (TX) and Receivers (RX) 540 coupled to processor 510, and a communication interface coupled to TX/RX 540. Memory 520 stores at least a portion of program 530. TX/RX 540 is used for two-way communication. TX/RX 540 has at least one antenna to facilitate communications, although in practice the access node referred to in the present application may have several antennas. The communication interface may represent any interface required for communication with other network elements, such as an X2 interface for bi-directional communication between enbs, an S1 interface for communication between a Mobility Management Entity (MME)/serving gateway (S-GW) and enbs, a Un interface for communication between enbs and Relay Nodes (RNs), or a Uu interface for communication between enbs and UEs.

The program 530 is assumed to include program instructions that, when executed by the associated processor 510, enable the apparatus 500 to operate in accordance with embodiments of the present disclosure, as discussed herein with reference to fig. 1-10. The embodiments herein may be implemented by computer software executable by the processor 510 of the device 500, or by hardware, or by a combination of software and hardware. Processor 510 may be configured to implement various embodiments of the present disclosure. Further, the combination of processor 510 and memory 520 may form a processing device 550 suitable for implementing various embodiments of the present disclosure.

Memory 520 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as non-transitory computer readable storage media, semiconductor-based storage devices, magnetic storage devices and systems, optical storage devices and systems, fixed memory, and removable memory, as non-limiting examples. Although only one memory 520 is shown in device 500, there may be several physically distinct memory modules in device 500. The processor 510 may be of any type suitable to the local technology network and may include, as non-limiting examples, one or more of a general purpose computer, a special purpose computer, a microprocessor, a Digital Signal Processor (DSP), and a processor based on a multi-core processor architecture. The device 500 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock that is synchronized to the master processor.

In general, the various embodiments of the disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of the embodiments of the disclosure are illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product comprises computer executable instructions, such as those included in program modules, for execution in a device on a target real or virtual processor to perform the methods 300, 400 described above with reference to fig. 3 and 4. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or split between program modules as desired. Machine-executable instructions of program modules may be executed within local or distributed devices. In distributed devices, program modules may be located in both local and remote memory storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program code may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, causes the functions/operations specified in the flowchart and/or block diagram to be implemented. The program code may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of this disclosure, computer program code or related data may be carried by any suitable carrier to enable an apparatus, device or processor to perform the various processes and operations described above. Examples of the carrier include a signal, a computer-readable medium.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of a computer-readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Moreover, although operations are described in a particular order, this should not be construed as requiring that such operations be performed in the particular order or sequence illustrated, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Also, while the above discussion contains several specific implementation details, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Although the disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method of communication, comprising:

Grouping, at the network device, a plurality of hybrid automatic repeat request, HARQ, processes for the terminal device into at least one HARQ group; and

in response to a failure to receive HARQ feedback for a HARQ process in the at least one HARQ group, transmitting to the terminal device first signaling for triggering transmission of the HARQ feedback, the first signaling comprising an indication for the at least one HARQ group.

2. The method of claim 1, wherein grouping the plurality of HARQ processes comprises:

determining a first timing indicator for a first HARQ process of the plurality of HARQ processes and a second timing indicator for a second HARQ process of the plurality of HARQ processes;

determining, based on the first timing indicator and the second timing indicator, whether the first HARQ process and the second HARQ process share an initial HARQ feedback transmission opportunity; and

in response to determining that the first HARQ process and the second HARQ process share the initial HARQ feedback transmission opportunity, the first HARQ process and the second HARQ process are grouped into a first HARQ group.

3. The method of claim 1, wherein grouping the plurality of HARQ processes comprises:

Determining whether a first downlink grant associated with a third HARQ process of the plurality of HARQ processes and a second downlink grant associated with a fourth HARQ process of the plurality of HARQ processes are transmitted in a single set of control resources; and

in response to determining that the first downlink grant and the second downlink grant are transmitted in a single set of control resources, the third HARQ process and the fourth HARQ process are grouped into a second HARQ group of the at least one HARQ group.

4. A method according to any of claims 1 to 3, wherein the indication for the at least one HARQ group comprises at least one of:

an identification of the at least one HARQ group, and

a bitmap, bits in the bitmap being associated with the at least one HARQ group.

5. A method according to any one of claims 1 to 3, further comprising:

transmitting second signaling for scheduling downlink transmissions to the terminal device, the second signaling comprising:

an identification of a fifth HARQ process of the plurality of HARQ processes, the fifth HARQ process associated with the downlink transmission, and

an indication of the HARQ group to which the fifth HARQ process is grouped.

6. A method according to any one of claims 1 to 3, further comprising:

transmitting third signaling to the terminal device for scheduling another downlink transmission, the third signaling comprising:

an identification of a sixth HARQ process of the plurality of HARQ processes, the sixth HARQ process associated with the other downlink transmission, and

an index of the sixth HARQ process in another HARQ group to which the sixth HARQ process is grouped.

7. The method of claim 6, wherein transmitting the first signaling comprises:

in response to a failure to receive HARQ feedback for the sixth HARQ process, transmitting the first signaling comprising an indication for the further HARQ group and a further bitmap, bits in the further bitmap being associated with the index of the sixth HARQ process.

8. A method of communication, comprising:

receiving first signaling from a network device, the first signaling for triggering transmission of at least one HARQ feedback for at least one hybrid automatic repeat request, HARQ, process, the first signaling comprising an indication for at least one HARQ group;

determining whether the indication indicates one or more HARQ groups to which the at least one HARQ process is grouped; and

The HARQ feedback is transmitted to the network device in response to determining that the indication indicates the one or more HARQ groups.

9. The method of claim 8, wherein the indication for the at least one HARQ group comprises at least one of:

an identification of the at least one HARQ group, and

a bitmap, bits in the bitmap being associated with the at least one HARQ group.

10. The method of claim 8 or claim 9, further comprising:

receiving second signaling from the network device for scheduling downlink transmissions, the second signaling comprising:

an identification of a fifth HARQ process of the at least one HARQ process, the fifth HARQ process associated with the downlink transmission, and

an indication of the HARQ group to which the fifth HARQ process is grouped.

11. The method of claim 10, wherein determining whether the indication indicates the one or more HARQ groups comprises:

determining whether the indication for the at least one HARQ group in the first signaling is the same as the indication for the HARQ group.

12. The method of claim 8 or claim 9, wherein determining whether the indication indicates the one or more HARQ groups comprises:

Determining an initial HARQ feedback transmission occasion for a second HARQ process of the at least one HARQ process based on a timing indicator received from the network device for the second HARQ process;

determining an HARQ group to which the second HARQ process is grouped based on the initial HARQ feedback transmission opportunity; and

determining whether the indication for the at least one HARQ group in the first signaling indicates the HARQ group.

13. The method of claim 8 or claim 9, wherein determining whether the indication indicates the one or more HARQ groups comprises:

determining, based on a set of control resources, a HARQ group to which a third HARQ process of the at least one HARQ process is grouped, a downlink grant associated with the third HARQ process being transmitted on the set of control resources; and

14. The method of claim 8 or claim 9, further comprising:

receiving third signaling from the network device for scheduling another downlink transmission, the third signaling comprising:

an identification of a fourth HARQ process of the at least one HARQ process, the fourth HARQ process being associated with the further downlink transmission, and

An index of the fourth HARQ process in another HARQ group to which the fourth HARQ process is grouped.

15. The method of claim 14, wherein receiving the first signaling comprises:

the first signaling is received comprising an indication for the further HARQ group and a further bitmap, bits in the further bitmap being associated with the index of the fourth HARQ process.

16. A network device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform the method of any one of claims 1 to 7.

17. A terminal device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform the method of any one of claims 8 to 15.

18. A computer readable medium having stored thereon a computer program which, when executed by a processor, causes the processor to perform the method according to any of claims 1 to 7.

19. A computer readable medium having stored thereon a computer program which, when executed by a processor, causes the processor to perform the method according to any of claims 8 to 15.