Dynamic indication of repetition for Msg4

Abstract

Example embodiments of the present disclosure relate to apparatuses, methods, and computer-readable storage media for dynamic indication of repetition of message 4 (Msg4). In the method, a device receives, from a network element during a random access procedure, a downlink control information (DCI) message that schedules Msg4 transmissions to a first device. In turn, the apparatus receives a scheduled Msg4 transmission from the network element on a scheduled physical downlink shared channel (PDSCH) for performing the random access procedure based on the DCI message. At least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor that is used to transmit at least one Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) for scheduled Msg4 transmissions.

Description

Technical Field

[0001] Various exemplary embodiments of this disclosure generally relate to the field of telecommunications, and more particularly to apparatus, methods and computer-readable storage media for a dynamic indication of repetition of message 4 (Msg4). Background Technology

[0002] In the 3rd Generation Partnership Project (3GPP), it has been agreed that the Physical Uplink Control Channel (PUCCH) used for Message 4 (Msg4) Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) needs to be enhanced to meet coverage requirements. Support for PUCCH repetition for Msg4 HARQ-ACK is expected. For example, one or more repetition factors can be configured for the PUCCH used for Msg4 HARQ-ACK via the System Information Block (SIB). However, during the random access procedure, it is necessary to distinguish between User Equipment (UEs) with and without the capability to repetite PUCCH for Msg4 HARQ-ACK to avoid erroneous reception of DCI for scheduling Msg4 or PUCCH repetition for Msg4 HARQ-ACK when multiple UEs with different capabilities transmit the same preamble at the same RACH timing (RO). Summary of the Invention

[0003] In a first aspect of this disclosure, an apparatus is provided. The apparatus includes: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: receive a downlink control information (DCI) message from a network element, the DCI message scheduling a message 4 (Msg4) transmission to the apparatus during a random access procedure; and, based on the DCI message, receive a scheduled Msg4 transmission from the network element on a scheduled physical downlink shared channel (PDSCH) for performing the random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used to transmit at least one hybrid automatic repeat request acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0004] In a second aspect of this disclosure, an apparatus is provided. The apparatus includes: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform at least: transmitting a downlink control information (DCI) message to a user equipment prior to a scheduled message 4 (Msg4) transmission on a scheduled physical downlink shared channel (PDSCH); and performing a scheduled Msg4 transmission to a user equipment during a random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used by the user equipment to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0005] In a third aspect of this disclosure, a method is provided. The method includes: receiving a downlink control information (DCI) message from a network element, the DCI message scheduling a message 4 (Msg4) transmission during a random access procedure; and receiving the scheduled Msg4 transmission from the network element on a scheduled physical downlink shared channel (PDSCH) for performing the random access procedure, based on the DCI message, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used to transmit at least one hybrid automatic repeat request acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0006] In a fourth aspect of this disclosure, a method is provided. The method includes: transmitting a downlink control information (DCI) message to a user equipment prior to a scheduled message 4 (Msg4) transmission on a scheduled physical downlink shared channel (PDSCH); and performing the scheduled Msg4 transmission to the user equipment during a random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor to be used by the user equipment to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0007] In a fifth aspect of this disclosure, a first apparatus is provided. The first apparatus includes: components for receiving downlink control information (DCI) messages from a network element, the DCI messages being scheduled as message 4 (Msg4) transmissions to the apparatus during a random access procedure; and components for receiving scheduled Msg4 transmissions from the network element based on the DCI messages on a scheduled physical downlink shared channel (PDSCH) for performing the random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0008] In a sixth aspect of this disclosure, a second apparatus is provided. The second apparatus includes: means for transmitting a downlink control information (DCI) message to a user equipment prior to a scheduled message 4 (Msg4) transmission to the user equipment on a scheduled physical downlink shared channel (PDSCH); and means for performing the scheduled Msg4 transmission to the user equipment during a random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor to be used by the user equipment to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0009] In a seventh aspect of this disclosure, a computer-readable medium is provided. The computer-readable medium includes instructions stored thereon for causing a device to at least execute the method according to the third aspect.

[0010] In an eighth aspect of this disclosure, a computer-readable medium is provided. The computer-readable medium includes instructions stored thereon for causing a device to at least execute the method according to the fourth aspect.

[0011] It should be understood that the summary portion is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0012] Some exemplary embodiments will now be described with reference to the accompanying drawings, in which: Figure 1 An example communication environment in which example embodiments of this disclosure may be implemented is shown; Figure 2 A signaling diagram illustrating communication between a first device 110 and a second device 120 according to some example embodiments of the present disclosure is shown; Figure 3A Signaling diagrams of communication between a UE and a gNB according to some example embodiments of this disclosure are shown; Figure 3B Another signaling diagram illustrating communication between a UE and a gNB according to some example embodiments of this disclosure is shown; Figure 3C Another signaling diagram illustrating communication between a UE and a gNB according to some example embodiments of this disclosure is shown; Figure 3D A signaling diagram illustrating communication between a first UE, a second UE, and a gNB according to some example embodiments of the present disclosure is shown; Figure 4 A flowchart is shown illustrating a method implemented at a first device according to some exemplary embodiments of the present disclosure; Figure 5 A flowchart is shown illustrating a method implemented at a second device according to some example embodiments of the present disclosure; Figure 6 A simplified block diagram of a device suitable for implementing example embodiments of the present disclosure is shown; and Figure 7 A block diagram of an example computer-readable medium according to some example embodiments of the present disclosure is shown.

[0013] Throughout the accompanying drawings, the same or similar reference numerals denote the same or similar elements. Detailed Implementation

[0014] The principles of this disclosure will now be described with reference to some exemplary 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 implementing this disclosure, and do not imply any limitation on the scope of this disclosure. The embodiments described herein can be implemented in various ways other than those described below.

[0015] In the following description and claims, unless otherwise defined, 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 pertains.

[0016] References to "an embodiment," "embodiment," "example embodiment," etc., in this disclosure indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment needs to include that particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Additionally, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is believed that, to the knowledge of those skilled in the art, other embodiments can be combined to affect that feature, structure, or characteristic, whether explicitly described or not.

[0017] It should be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements are not limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the exemplary embodiments. As used herein, the term “and / or” includes any and all combinations of one or more of the listed terms.

[0018] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, wherein a list of two or more elements combined with “and” or “or” means at least one of the elements, or at least any two or more of the elements, or at least all of the elements.

[0019] As used herein, unless explicitly stated otherwise, the execution step “in response to A” does not indicate that the step is performed immediately after “A” occurs, and may include one or more intervention steps.

[0020] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments. As used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It will be further understood that the terms “comprising,” “including,” “having,” “having,” “containing,” and / or “comprising” as used herein specify the presence of the stated features, elements, and / or components, etc., but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0021] As used in this application, the term "circuit system" may refer to one or more of the following: (a) Hardware circuit implementation only (such as implementation only in analog and / or digital circuit systems) and (b) Combinations of hardware circuitry and software, for example (if applicable): (i) A combination of analog and / or digital software circuits with software / firmware, and (ii) Any part of a hardware processor (including multiple digital signal processors, software, and multiple memories, which work together to enable a device (such as a mobile phone or server) to perform various functions) (c) (Multiple) hardware circuits and / or (multiple) processors, such as (multiple) microprocessors or a portion thereof, which require software (e.g. firmware) to operate, but may not exist when the software is not required to operate.

[0022] This definition of circuit system applies to all uses of the term in this application (including any claim). As another example, as used in this application, the term circuit system also covers implementations of hardware circuitry or processors (or processors) or hardware circuitry or processors and their accompanying software and / or firmware. The term circuit system also covers, for example (and if applicable to a particular claim element), baseband integrated circuits or processor integrated circuits used in mobile devices or similar integrated circuits in servers, cellular network devices or other computing or networking devices.

[0023] As used herein, the term "communication network" refers to a network that conforms to any suitable communication standard, such as New Radio (NR), Long Term Evolution (LTE), LTE-A Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), etc. Furthermore, communication between terminal devices and network devices in a communication network can be performed according to any suitable generation of communication protocol, including but not limited to first-generation (1G), second-generation (2G), 2.5G, 2.75G, third-generation (3G), fourth-generation (4G), 4.5G, fifth-generation (5G), sixth-generation (6G) communication protocols and / or any other currently known or future-developed protocols. Embodiments of this disclosure can be applied to a variety of communication systems. Given the rapid development of communications, there will certainly be future types of communication technologies and systems that embody the future types of this disclosure. The scope of this disclosure should not be considered limited to the aforementioned systems.

[0024] As used herein, the term "network device" refers to a node in a communications network through which terminal devices access the network and receive services. Network devices can refer to base stations (BS) or access points (APs), such as Node B (or NB), evolved Node B (e Node B or eNB), NR NB (also known as gNB), Remote Radio Unit (RRU), Radio Header (RH), Remote Radio Header (RRH), relay, Integrated Access and Backhaul (IAB) node, low-power nodes such as femtoseconds, picoseconds, non-terrestrial network (NTN) or non-terrestrial network equipment (such as satellite network equipment, low Earth orbit (LEO) satellites and geostationary Earth orbit (GEO) satellites), spacecraft network equipment, etc., depending on the terminology and technology applied. In some example embodiments, the Radio Access Network (RAN) split architecture includes a Central Unit (CU) and a Distributed Unit (DU) at the IAB donor node. An IAB node includes a Mobile Terminal (IAB-MT) portion that behaves as if facing a UE to the parent node, and the DU portion of the IAB node behaves as if facing a base station to the next-hop IAB node.

[0025] The term "terminal device" or "user equipment" refers to any terminal device capable of wireless communication. By way of example and not limitation, a terminal device may also be referred to as a communication device, user equipment (UE), subscriber station (SS), portable subscriber station, mobile station (MS), or access terminal (AT). Terminal devices can include, but are not limited to, mobile phones, cellular phones, smartphones, Voice over IP (VoIP) phones, wireless local loop phones, tablet computers, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image acquisition terminal devices such as digital cameras, gaming terminal devices, music storage and return devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), laptop-mounted devices (LMEs), USB dongles, smart devices, wireless customer premises equipment (CPEs), Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronic devices, devices operating on commercial and / or industrial wireless networks, etc. The terminal device may also correspond to the mobile terminal (MT) portion of an IAB node (e.g., a relay node). In the following description, the terms "terminal device," "communication device," "terminal," "user equipment," and "UE" are used interchangeably.

[0026] As used herein, the terms “resource,” “transmission resource,” “resource block,” “physical resource block” (PRB), “uplink resource,” or “downlink resource” can refer to any resource used to perform communication, such as communication between a terminal device and a network device, including time-domain resources, frequency-domain resources, spatial-domain resources, code-domain resources, or any other resources capable of communication. In the following, unless explicitly stated otherwise, resources in the frequency and time domains may be used as examples of transmission resources used to describe some exemplary embodiments of this disclosure. Note that the exemplary embodiments of this disclosure are equally applicable to other resources in other domains.

[0027] Version 18 (Rel-18) Non-Terrestrial Network (NTN) targets focus on the applicability of solutions developed for NTN coverage enhancements by Universal New Radio (NR). Furthermore, if necessary, the Rel-18 NTN targets identify potential problems and enhancements, taking into account NTN characteristics including large propagation delays and satellite movement.

[0028] In the 3rd Generation Partnership Project (3GPP), it was concluded that the Physical Uplink Control Channel (PUCCH) used for Message 4 (Msg4) Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) could be enhanced to meet the coverage requirements for Parameter Set-1 of Low Earth Orbit (LEO)-1200 operating in line-of-sight (LOS) mode, assuming a User Equipment (UE) antenna gain of -5 dBi, as existing designs could not meet performance requirements with a gap of 1.8 to 6 dB. Later, the expected loss of the UE antenna gain was reduced from -5 dBi to -5.5 dBi, but the overall conclusion remained unchanged.

[0029] Furthermore, it is expected that Rel-18 can support PUCCH repetition for Msg4 HARQ-ACK. One or more repetition factors can be configured via the System Information Block (SIB) for the PUCCH for Msg4 HARQ-ACK. If multiple factors from {1, 2, 4, 8} are configured via the SIB, PUCCH repetition for Msg4 HARQ-ACK can be dynamically determined and indicated by the NR Node B (also known as the NR NB or gNB).

[0030] Fields in the downlink control information (DCI) of the scheduling Msg4 physical downlink shared channel (PDSCH) can be used for dynamic indication of the repetition factor from the gNB. For this purpose, in one example, one or two bits of the modulation and coding scheme (MCS) field can be used. In another example, one or two bits of the PUCCH resource indicator field (e.g., with repetition factor configuration per PUCCH resource) can be used. In yet another example, one or two bits of the HARQ process number field can be used. In yet another example, one or two bits of the downlink allocation index (DAI) field can be used. In yet another example, one or two bits of the PDSCH to HARQ feedback timing indicator field can be used. In yet another example, a new field with one or two bits can be used.

[0031] Alternatively, the fields in the uplink (UL) grant of the Physical Uplink Shared Channel (PUSCH) in Scheduling Message 3 (Msg3) can be used for dynamic indication of the repetition factor from the gNB. The PUCCH repetition factor and the Msg3 repetition factor can be jointly indicated by using a predefined or configured relationship between the PUCCH repetition factor and the Msg3 repetition factor.

[0032] Alternatively, the cyclic redundancy check (CRC) scrambling of the DCI of the scheduling Msg4 PDSCH can be used for dynamic indication of the repetition factor from the gNB. For example, one or two CRC bits in addition to the bits scrambled by TC-RNTI can be used for dynamic indication.

[0033] Alternatively, the implicit mapping between the Msg4 HARQ ACK repeat factor and the Msg3 PUSCH repeat factor can be used for dynamic indication of repeat factors from the gNB, and this implicit mapping does not have reinterpreted fields or new fields (i.e., it does not change the DCI design).

[0034] Regarding the indication of PUCCH repetition capability from UE to gNB, the following assumptions are also made. For PUCCH repetition for Msg4HARQ-ACK, the Physical Random Access Channel (PRACH) preamble and / or timing can be used as a container for the repetition request or capability report indicated by the UE. In this case, it is necessary to further investigate whether PRACH resource allocation is required for the indication of repetition request or capability report. Furthermore, it is necessary to further investigate whether the indication of repetition factor is assumed. The relationship with REL-18 NR coverage enhancement for PRACH may also need to be considered. Alternatively, higher-layer signaling in Msg3 PUSCH can be used as a container for the repetition request or capability report indicated by the UE. In this case, it is necessary to further investigate which signaling to use. Alternatively, physical layer signaling in Msg3 PUSCH can be used as a container for the repetition request or capability report indicated by the UE. In this case, it is necessary to further investigate which signaling (e.g., demodulation reference signal (DMRS) port) to use.

[0035] The latter two options are currently preferred because indicating UE capabilities via PRACH resources will lead to an increased probability of collisions during PRACH, which will significantly increase UE access latency, especially in NTN systems affected by large round-trip times, or require reserving unnecessary additional PRACH resources for the selected UE to indicate potential support for features.

[0036] In the existing design, the fields of DCI format 1_0 are defined for PDSCH scheduling. The DCI format 1_0 of scheduling Msg4, scrambled by the Temporary Cell Radio Network Temporary Identifier (TC-RNTI), includes a reserved bit field. If the DCI format is monitored in the common search space for operation in cells within frequency range 2-2, and the number of bits used for the “ChannelAccess-CPext” field is 0, then the reserved bit field may include 2 bits. Otherwise, these reserved bit fields may include 0 bits.

[0037] Observation: If there is no distinction in the PUCCH between UEs with and without the ability to repeat PUCCH for Msg4 HARQ-ACK, multiple UEs with such different capabilities can transmit the same preamble in the same RACH timing (RO). In this case, the gNB will not be able to distinguish those multiple UEs that have been allocated the same uplink (UL) grant and TC-RNTI for subsequent Msg3 transmissions. Therefore, multiple UEs with different capabilities transmit Msg3 in the same time-frequency resources, using the same TC-RNTI scrambling payload. However, the gNB may only be able to detect the UE with the dominant signal among the multiple UEs and can use the contention resolution message addressing these dominant UEs to transmit subsequent Msg4. Furthermore, Msg4 is carried in the PDSCH scheduled by DCI 1_0, which has a CRC scrambled by the TC-RNTI used by multiple UEs for Msg3 transmission. However, since multiple UEs do not know which of them is the dominant UE in Msg3 (i.e., each of the multiple UEs is unaware of the other UEs), they may all attempt to receive and decode this DCI 1_0 with a CRC scrambled by TC-RNTI that carries the scheduling information for Msg4. This scenario may be referred to below as a "preamble collision (PC)". This PC typically occurs under conditions of high cell load.

[0038] If it is assumed that the dynamic indication of the repetition factor from the gNB for a UE with PUCCH repetition capability is performed by reusing the DCI field as, for example, the MCS field, but the dominant Msg3 comes from a UE among multiple UEs that does not have PUCCH repetition capability, then the gNB transmits the DCI with the non-reused MCS field for the scheduled Msg4 (and its CRC scrambled with TC-RNTI). Otherwise, the DCI with the reused MCS field can be transmitted.

[0039] The two sub-cases of PC will be described in detail below. For the first sub-case of PC, in the case where the gNB transmits a DCI with a non-repurposed MCS field for Msg4, a UE with this capability may have problems decoding Msg4 because it assumes the field has been repurposed and therefore may misinterpret the MCS index. It may also send a duplicate negative acknowledgment (NACK) to the gNB in ​​a resource that is not allocated for such duplication because the MCS field is not actually repurposed. Therefore, interference may be introduced on time-frequency resources not allocated for PUCCH transmission.

[0040] In the second sub-case of the PC, in the case of DCI with modified MCS that schedules Msg4 in gNB transmission, the incapable UE may have problems decoding Msg4 due to misinterpretation of the MCS index, and cause RACH to be retried after the contention resolution timer expires (i.e., the RACH process restarts from the PRACH transmission).

[0041] Even though the example uses one or two bits of the MCS field, the same ambiguity exists for other of the above alternatives and generally whenever an existing field in the DCI is repurposed.

[0042] An exemplary embodiment of this disclosure proposes a scheme for indicating a PUCCH repetition factor for a Msg4 HARQ-ACK. Using this scheme, reserved bits in the DCI message used to schedule Msg4 transmissions are multiplexed in association with an indication of the repetition factor, which is used to transmit at least one HARQ-ACK for the scheduled Msg4 transmission.

[0043] The proposed scheme avoids ambiguity in PC scenarios. For example, in the first PC sub-case (the field where reserved bits are not reused), even UEs with PUCCH repeat capability can correctly interpret the DCI (because the reserved bits may simply be set to 0), decode Msg4, and immediately restart the RACH procedure without waiting for the contention resolution window to end and without transmitting a "NACK" that occupies resources not allocated for repeating. In the second PC sub-case (the field where reserved bits are reused), even UEs without PUCCH repeat capability can decode the message (because they can ignore the contents of the reserved bit field) and immediately restart the RACH procedure without waiting for the contention resolution window to end, thus improving RACH performance. Therefore, the random access procedure can be more efficient and effective.

[0044] Figure 1 An example communication environment 100 in which exemplary embodiments of the present disclosure may be implemented is shown. In the communication environment 100, the first device 110 and the second device 120 may communicate with each other.

[0045] In the following description, for illustrative purposes, some exemplary embodiments are depicted in which the first device 110 operates as a terminal device and the second device 120 operates as a network device. However, in some exemplary embodiments, the operations described in connection with the terminal device can be implemented at the network device or other devices, and the operations described in connection with the network device can be implemented at the terminal device or other devices.

[0046] In some example embodiments, if the first device 110 is a terminal device and the second device 120 is a network device, the link from the second device 120 to the first device 110 is referred to as a downlink (DL), and the link from the first device 110 to the second device 120 is referred to as an uplink (UL). In the DL, the second device 120 is a transmitting (TX) device (or transmitter), and the first device 110 is a receiving (RX) device (or receiver). In the UL, the first device 110 is a TX device (or transmitter), and the second device 120 is an RX device (or receiver).

[0047] Communication in communication environment 100 can be implemented according to any suitable communication protocol(s), including but not limited to cellular communication protocols such as first-generation (1G), second-generation (2G), third-generation (3G), fourth-generation (4G), fifth-generation (5G), and sixth-generation (6G), wireless local area network communication protocols such as IEEE 802.11, and / or any other currently known or future-developed protocols. Furthermore, communication can utilize any suitable wireless communication technology, including but not limited to: Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple-Input Multiple-Output (MIMO), Orthogonal Frequency Division Multiple Access (OFDM), Discrete Fourier Transform Extended OFDM (DFT-s-OFDM), and / or any other currently known or future-developed technologies.

[0048] Figure 2 Signaling diagram 200 illustrates communication between a first device 110 and a second device 120 according to some example embodiments of the present disclosure. Although in Figure 2 A first device 110 and a second device 120 are shown, but it should be understood that there may be multiple first devices performing operations similar to those described below with respect to the first device 110 and multiple second devices performing operations similar to those described below with respect to the second device 120.

[0049] The second device 120 transmits a (205) DCI message to the first device 110 on the scheduled PDSCH prior to the scheduler's Msg4 transmission. Accordingly, the first device 110 receives a (210) DCI message from the second device 120. The DCI message includes at least one reserved bit multiplexed in association with an indication of a repetition factor used to transmit at least one HARQ-ACK for the scheduled Msg4 transmission.

[0050] After transmitting the (205) DCI message, the second device 120 performs the (215) scheduled Msg4 transmission to the first device 110 during the random access procedure. Accordingly, the first device 110 receives the (220) scheduled Msg4 transmission from the second device 120 on the scheduled PDSCH for performing the random access procedure.

[0051] After receiving the scheduled Msg4, the first device 110 may also transmit (225) at least one HARQ-ACK for the scheduled Msg4 to the second device 120 via PUCCH. Accordingly, the second device 120 may receive (230) at least one HARQ-ACK from the first device 110.

[0052] In some example embodiments, reserved bits in DCI 1_0 with a CRC scrambled by TC-RNTI can be repurposed to carry a PUCCH repetition factor for Msg4 HARQ-ACK. Alternatively, as a fallback, reserved bits can be repurposed to extend the use of reserved bits currently present in DCI 1_0 (or, referred to herein as replacement bits) when a new field for PUCCH repetition is introduced in DCI 1_0 with a CRC scrambled by TC-RNTI, but this field is absent in a particular instance of DCI 1_0 with a CRC scrambled by TC-RNTI due to, for example, the UE not supporting the ability to PUCCH repetition for Msg4 HARQ-ACK, or because only one repetition factor is configured for PUCCH repetition, or because no repetition factor is configured for PUCCH repetition. In practice, for example, in the absence of a repetition factor configured, the UE can be expected to transmit HARQ-ACK without repetition, such that no bits are allocated to the newly introduced field for dynamic indication of PUCCH repetition. In this context, to maintain a constant DCI size, which is important for the DCI size alignment rules defined in TS 38.212, it is necessary to replace missing bits (replacing missing bits in the newly introduced field used for dynamic indication of PUCCH repetition), which is the objective of this disclosure. According to some example embodiments of this disclosure, the operation of the currently existing reserved bits can be extended, which will be described in detail below.

[0053] In some example embodiments, at least one reserved bit is multiplexed to indicate a repetition factor, which is used to transmit at least one HARQ-ACK in response to a scheduled Msg4 transmission. In some example embodiments, a first device 110 (which may operate as a user equipment) may receive a configuration for multiple repetition factors from a second device 120 (which may operate as a network unit), which can be used for at least one HARQ-ACK for a scheduled Msg4 transmission. In this example, the indicated repetition factor is selected from multiple repetition factors.

[0054] In the example, when multiple values ​​for the repeat factor are configured and the UE supports the capability for PUCCH repeating, the purpose of the reserved bit can be extended to map code points to values ​​of the PUCCH repeat factor. When only one repeat factor is configured, or when the repeat factor is not configured via a higher layer, the reserved bit can be forcibly ignored, matched to the configured repeat factor, or used to provide the UE with confirmation regarding whether to use a configured repeat factor. Alternatively, in this scenario, the reserved bit may not exist, and the field size of the reserved bit may be equal to 0 bits. Furthermore, when multiple values ​​for the repeat factor are configured but the UE does not support the capability for PUCCH repeating, the reserved bit can be forcibly set to 0 or may not exist.

[0055] In some example embodiments, the repetition factor can be indicated via a field in the DCI message, wherein when the field is not present in the DCI message, at least one reserved bit can be extended to be used as a backoff bit(s).

[0056] In some example embodiments, this field in the DCI message may be absent in the following situations: no repetition factor is configured; a repetition factor is configured for at least one HARQ-ACK for a scheduled Msg4 transmission; the device is not capable of supporting repetition for at least one HARQ-ACK for a scheduled Msg4 transmission.

[0057] In the example, the use of reserved bits can be extended to serve as backoff bits in situations where a new field for PUCCH repetition is introduced, but this field does not exist for a specific instance of DCI 1_0 scrambled with TC-RNTI. For example, the new field may not exist in one of the following situations: the PUCCH repetition factor is not configured, or only one repetition factor is configured, or the UE does not support PUCCH repetition capability. This example embodiment will be described in detail later.

[0058] In some example embodiments, a first device 110 (which may operate as a user equipment) may transmit an indication of a preference repetition factor to a second device 120 (which may operate as a network element). This preference repetition factor is used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission. In this example, at least one reserved bit may be multiplexed to indicate whether the preference repetition factor is applied. In some example embodiments, the second device 120 may determine that at least one reserved bit indicates that the preference repetition factor is not applied. The first device 110 may then transmit a HARQ-ACK for the scheduled Msg4 transmission to the network element, the HARQ-ACK having no repetitions or having a predetermined number of repetitions.

[0059] In the example, the UE may be able to indicate a preference for a given (e.g., pre-configured) repetition factor from a larger set. As an example, and not a limitation, the set could include 1, 2, 4, and 8. In this case, the UE can indicate one of the values ​​in the set to the gNB. The gNB can use a single reserved bit of DCI 1_0 to represent "acknowledgment" of the UE's preference. In this case, if the UE indicates a preference for repetition factor 4, the gNB can trigger a repetition by the UE by setting a value of "1," while a value of "0" can indicate "no repetition will be used." Alternatively, Table 2 shown below can be updated to be compatible where repetitions indicated by the UE and repetitions determined by the gNB can coexist, meaning that 2 bits are also used.

[0060] In some example embodiments, at least one reserved bit may be multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission.

[0061] In the example, the purpose of the reserved bit can be extended to allow the UE to understand whether a field in DCI 1_0 with a CRC scrambled by TC-RNTI has been repurposed. As an example and not a limitation, this field can be one of the following: MCS field, PUCCH resource indicator field, HARQ process number field, DAI field, PDSCH to HARQ feedback timing indicator field.

[0062] Based on the solutions according to some example embodiments of this disclosure, no ambiguity is expected, and thus the above-mentioned PC problem is solved.

[0063] For illustrative purposes, several examples of higher-layer configurations and physical layer signaling are listed below. Table 1 shows an example configuration of the PUCCH repeat indicator for Msg4 HARQ-ACK in pucch-ResourceCommon.

[0064] Table 1. Configuration of PUCCH repeat indicator in pucch-ResourceCommon

[0065] Table 2 shows an example of the PUCCH repeat indicator for Msg4 HARQ-ACK in a DCI scrambled by TC-RNTI in format 1_0.

[0066] Table 2. PUCCH repeat indicators corresponding to the repeat factor in pucch-RepetitionNrofSlot-r18

[0067] Table 3 shows an example of the confirmation of the repetition factor for UE reporting preferences.

[0068] Table 3 Confirmation of UE Preference Repetition Factor

[0069] Table 4 shows an example of a two-bit refactoring indicator for a field in the DCI of the scheduled Msg4 PDSCH.

[0070] Table 4. Reuse Indicators with 2 Bits

[0071] Table 5 shows an example of a refactoring indicator for a single bit of a field in the DCI for scheduling Msg4 PDSCH.

[0072] Table 5 shows the repurpose indicator with 1 bit.

[0073] In some example implementations, both ACK and NACK can be repeated in order to take advantage of the gain from repeated combinations.

[0074] The purpose of the reserved bit extension will be described in detail below to indicate the PUCCH repetition factor used for Msg4 HARQ feedback.

[0075] In some example embodiments, when the UE has not yet been provided with a C-RNTI, in response to a PUSCH transmission scheduled by a Random Access Response (RAR) UL grant, the UE may attempt to detect a DCI format 1_0 with a CRC scrambled by the corresponding TC-RNTI, which schedules a PDSCH including the UE contention resolution identifier. Fields included in the DCI format 1_0 with a CRC scrambled by the TC-RNTI are defined. Specifically, the “ChannelAccess-CPext” feature occupies the last two bits along with reserved bits.

[0076] In some example embodiments, if channelAccessMode-r16 = "semi-static" is provided, ChannelAccess-CPext may include 2 bits indicating a combination of channel access type and cyclic prefix (CP) extension for operation in cells with shared spectrum channel access in frequency range 1. If channelAccessMode2-r17 is provided for operation in cells in frequency range 2-2, ChannelAccess-CPext may include 2 bits indicating the channel access type. Otherwise, ChannelAccess-CPext may include 0 bits. Additionally, when the DCI format is monitored in the common search space for operation in cells in frequency range 2-2 and the number of bits for the "ChannelAccess-CPext" field is 0, reserved bit fields may include 2 bits. Otherwise, these reserved bit fields may include 0 bits.

[0077] In some example embodiments, NTN operation is expected to be mutually exclusive with the "ChannelAccess-CPext" feature, which can be used for operation in unlicensed bands or frequency range 2-2. Based on this assumption, the description of reserved bits can be updated, for example, as follows: a new field for indicating the PUCCH repetition factor (called the PUCCH repetition indicator) is introduced in DCI 1_0 with a CRC scrambled by TC-RNTI, and the use of reserved bits is extended to be used as replacement bits in the case of missing bits in the new field (e.g., because no repetition factor is configured). For example, the PUCCH repetition indicator may include 2 bits when pucch-RepetitionNrofSlot-r18 is present in the SIB. Otherwise, the PUCCH repetition indicator may include 0 bits. The reserved bit field may include 2 bits when the DCI format is monitored in the common search space for operation in cells in frequency range 2-2 and the number of bits in the "ChannelAccess-CPext" field is 0. When the DCI format is monitored in a common search space for operation in cells within a frequency range different from frequency range 2-2 and the number of bits in the "PUCCH Repeat Indicator" field is 0, the reserved bit field may include 2 bits. Otherwise, the reserved bit field may include 0 bits. In this case, the reserved bit field is modified to account for the case where the PUCCH Repeat Indicator field is 0 bits in size.

[0078] In some example implementations, without introducing any new fields, the reserved bits are directly reused to indicate the PUCCH repetition factor from the configured table pucch-RepetitionNrofSlot-r18, and the canonical text can be updated, for example, as follows: - Reserved bits - when the DCI format is in a common search space for operation in cells within frequency range 2-2. When monitored and the "ChannelAccess-CPext" field has 0 bits, it uses 2 bits; when the DCI format is used in conjunction with frequency... The operation of cells in different frequency ranges 2-2 is monitored in the common search space and exists in the SIB. When `pucch-RepetitionNrofSlot-r18`, use 2 bits; otherwise, use 0 bits. In some example embodiments, when the UE indicates a preference for a given pre-configured repetition factor to the gNB, the gNB may instead use one of the reserved bits to indicate an entry in the configured Table 3 to indicate whether the UE prefers the repetition factor to be applied (the third example embodiment described above). The gNB may transmit a "0" to discard the preferred repetition factor. The preferred repetition factor may be indicated by the UE via, for example, Msg3 signaling. When the gNB transmits a "0", the UE may not perform repetition, or may perform a fixed number of repetitions, which may be configured by a higher layer or hard-coded in the specification. Furthermore, the gNB may transmit a "1" to acknowledge the repetition factor as the UE's preference.

[0079] As an example, and not a limitation, the reserved bit can be updated as follows: -Reserved bits- When the DCI format is in the common search space for operation in cells within frequency range 2-2 When monitored and the "ChannelAccess-CPext" field has 0 bits, it uses 2 bits; when the DCI format is used in conjunction with frequency... The operation of cells in different frequency ranges 2-2 is monitored in the common search space and exists in the SIB. When `pucch-RepetitionNrofSlot-r18`, 1 bit; otherwise, 0 bits. Alternatively, if the repetition indicated by the UE and the repetition determined by the gNB can coexist, Table 2 can be updated to be compatible, meaning that 2 bits are also used. In this case, the reserved bits can be updated as follows: -Reserved bits- When the DCI format is in the common search space for operation in cells within frequency range 2-2 When monitored and the "ChannelAccess-CPext" field has 0 bits, it uses 2 bits; when the DCI format is used in conjunction with frequency... The operation of cells in different frequency ranges 2-2 is monitored in the common search space and exists in the SIB. 2 bits for acknowledgment indicator; 0 bits otherwise. In some example embodiments, the use of reserved bits is extended to indicate whether a DCI field has been repurposed (fourth example embodiment above), and Table 4 is configured. For example, the gNB can transmit "01" to indicate that a field in the DCI (i.e., MCS / DAI, etc.) has not been repurposed because the gNB detects that the UE does not have repetition capability. Rel-18 UEs with and without capability can interpret the MCS / DAI (not repurposed) in the conventional manner. The gNB can transmit "10" to indicate that the DCI (i.e., MCS / DAI) has been repurposed because the gNB detects that the UE has repetition capability. UEs with PUCCH repetition capability can decode the MCS / DAI using the repurposed method and perform the indicated repetition. UEs without PUCCH repetition capability will not transmit NACK because they understand that Msg4 is not directed at themselves and quickly restart the RACH procedure without waiting for the contention resolution window to end.

[0080] It is understandable that the features “ChannelAccess-CPext” and PUCCH repetition are assumed to be mutually exclusive, because NTN does not expect to operate in unlicensed frequency bands or in frequency range 2-2.

[0081] The following will refer to Figures 3A to 3D This section discusses some example procedures for the repeated dynamic indication of Msg4. In these examples, such as... Figure 1 and Figure 2 The first device 110 shown can operate as a UE, and as... Figure 1 and Figure 2 The second device 120 shown can be operated as a gNB.

[0082] Figure 3A Signaling diagram 300 illustrates communication between a UE and a gNB according to some example embodiments of this disclosure.

[0083] exist Figure 3A In the example embodiment shown, if puchRepetitionNrofSlots-r18 exists in the SIB, in Figure 3A If represented as 302, then the size of the PUCCH repeat indicator field in DCI format 1_0 scrambled by TC-RNTI can be 2 bits. The UE can indicate the ability to repeat PUCCH for Msg4 HARQ feedback in Msg3 scrambled by TC-RNTI. Figure 3A This is represented as 304. After the transmission of Msg3, the UE can attempt to detect DCI format 1_0 scrambled by TC-RNTI, which carries a PUCCH repeat indicator (as described above) to indicate the repeat factor for the UE supporting repeating. Figure 3AIn this context, it is represented as 306. For UEs that support PUCCH repetition, the PUCCH repetition indicator is "00", and the corresponding repetition factor is "1" (only 1 PUCCH transmission). The UE can be instructed to use PUCCH resources in the time slot. Upload PUCCH, in Figure 3A The value is represented as 308, where Provided by the PUCCH repeat factor in Table 2.

[0084] Figure 3B Another signaling diagram 310 illustrates communication between a UE and a gNB according to some example embodiments of this disclosure.

[0085] exist Figure 3B In the example embodiments shown, when the PUCCH repetition factor is not configured, or only one repetition factor is configured, or the UE does not support PUCCH repetition capability, Figure 3B Represented as 312, the DCI of scheduling Msg4 can retain 2 bits reserved for a constant DCI size. Figure 3B The value is represented as 316, regardless of the UE's capabilities. Figure 3B This is represented as 314. If a PUCCH repetition factor is not configured, or the UE does not support PUCCH repetition capability, the UE should not transmit a PUCCH with repetition. If only one repetition factor is configured, the UE should transmit a PUCCH with the configured repetition factor. Figure 3B The value is represented as 318.

[0086] Figure 3C Another signaling diagram 320 illustrates communication between a UE and a gNB according to some example embodiments of this disclosure.

[0087] exist Figure 3C In the example embodiment shown, the UE can, for example, report the preference repetition factor in Msg3, in Figure 3C This is represented as 324. The gNB can transmit DCI with an acknowledged schedule Msg4, for example, by using one or two bits of the reserved field instead. Figure 3C This is represented as 326. If an acknowledgment is received, the UE can transmit PUCCH repeats according to its preferred repeat factor. Figure 3C This is represented as 328. If a negative acknowledgment is received, the UE may choose not to transmit duplicates or transmit a fixed number of duplicates.

[0088] Figure 3D Signaling diagram 330 illustrates communication between a first UE, a second UE, and a gNB according to some example embodiments of the present disclosure.

[0089] exist Figure 3DIn the example embodiment shown, the first UE UE1 and the second UE UE2 are in a PC scenario. For example, the gNB can receive Msg3 from UE2 (which is a Rel-18 UE with repeatability), and then transmit a DCI with a modified MCS (as an example, even if any field in the DCI can be modified) and a modification indicator. Figure 3D Represented as 338, UE2 can transmit repeated PUCCHs based on the repetition factor carried in the DCI. Figure 3D The value is represented as 340.

[0090] In view of the above, there is no ambiguity regarding PC scenarios in the solutions of some example embodiments of this disclosure. In the first PC sub-case (non-repurposed field of reserved bits), even UEs with PUCCH repeat capability will be able to correctly interpret the DCI (because the reserved bits will be set to 0), decode Msg4, and immediately restart the RACH process without waiting for the contention resolution window to end and without transmitting a "NACK" with a repeat that occupies resources not allocated for repeating. In the second PC sub-case (repurposed field of reserved bits), even UEs without PUCCH repeat capability will be able to decode the message (because they will ignore the contents of the reserved bit field) and immediately restart the RACH process without waiting for the contention resolution window to end, thus improving RACH performance. PC scenarios typically occur under high cell load conditions, which are not extreme cases. Conversely, alternatives that repurpose existing fields cannot avoid these problems and lead to a degraded RACH performance.

[0091] Example Method Figure 4 A flowchart of an example method 400 implemented at a first device according to some example embodiments of the present disclosure is shown. For the purposes of discussion, [the following will be discussed]. Figure 1 The angle description method of the first device 110 in the middle is 400.

[0092] At frame 410, the first device 110 receives a DCI message from the network unit, which is scheduled to be transmitted to the device as message 4 (Msg4) during the random access procedure.

[0093] At block 420, the first device 110 receives a scheduled Msg4 transmission from a network element on a scheduled PDSCH used for performing a random access procedure, based on a DCI message. At least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, which is used to transmit at least one HARQ-ACK for the scheduled Msg4 transmission.

[0094] In some example embodiments, at least one reserved bit may be multiplexed as an indicator of a repetition factor, which is used to transmit at least one HARQ-ACK in response to a scheduled Msg4 transmission.

[0095] In some example embodiments, the first device 110 may receive configuration for multiple repetition factors from a network element, which can be used for at least one HARQ-ACK for a scheduled Msg4 transmission. The indicated repetition factors may be selected from the multiple repetition factors.

[0096] In some example embodiments, the first device 110 may transmit an indication of a preference repetition factor to the network element, the preference repetition factor being used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission. At least one reserved bit may be multiplexed to indicate whether the preference repetition factor is applied.

[0097] In some example embodiments, based on determining that at least one reserved bit indicates that a preference repetition factor has not been applied, the first device 110 may transmit a HARQ-ACK for a scheduled Msg4 transmission to a network unit, the HARQ-ACK having no repetitions or having a predetermined number of repetitions.

[0098] In some example embodiments, at least one reserved bit may be multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, which is used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission.

[0099] In some example embodiments, the first device 110 may transmit to the network element an indication of the ability to repeat at least one HARQ-ACK for a scheduled Msg4 transmission. At least one reserved bit may be multiplexed based on the indicated capability.

[0100] In some example embodiments, the repetition factor can be indicated via a field in the DCI message, wherein when the field is not present in the DCI message, at least one reserved bit can be extended to be used as a backoff bit(s).

[0101] In some example embodiments, fields in a DCI message may be absent in response to one or more of the following: no repetition factor is configured; a repetition factor is configured for at least one HARQ-ACK for a scheduled Msg4 transmission; and the device does not have the capability to support repetition of at least one HARQ-ACK for a scheduled Msg4 transmission.

[0102] In some example embodiments, at least one HARQ-ACK for a scheduled Msg4 transmission may be transmitted via the Physical Uplink Control Channel (PUCCH).

[0103] Figure 5 A flowchart of an example method 500 implemented at a second device according to some example embodiments of the present disclosure is shown. For the purposes of discussion, [the following will be discussed]. Figure 1 The second device 120 in the method of angle description 500.

[0104] At frame 510, the second device 120, prior to the scheduled transmission of message 4 (Msg4) to the user equipment on the scheduled PDSCH, transmits the DCI message to the user equipment; and In block 520, the second device 120 performs a scheduled Msg4 transmission to the user equipment during the random access procedure. At least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor to be used by the user equipment to transmit at least one HARQ-ACK for the scheduled Msg4 transmission.

[0105] In some example embodiments, at least one reserved bit may be multiplexed as an indicator of a repetition factor, which is used to transmit at least one HARQ-ACK in response to a scheduled Msg4 transmission.

[0106] In some example embodiments, the second device 120 transmits a configuration for multiple repetition factors to the user equipment, which can be used for at least one HARQ-ACK for a scheduled Msg4 transmission. The indicated repetition factors may be selected from the multiple repetition factors.

[0107] In some example embodiments, the second device 120 may receive an indication of a preference repetition factor from the user equipment, the preference repetition factor being used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission. At least one reserved bit may be multiplexed to indicate whether the preference repetition factor is applied.

[0108] In some example embodiments, at least one reserved bit indicates that a preference repetition factor has not been applied. The second device 120 may receive at least one HARQ-ACK for a scheduled Msg4 transmission from the user equipment, wherein the at least one HARQ-ACK has no repetition or has a predetermined number of repetitions.

[0109] In some example embodiments, at least one reserved bit may be multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, which will be used by additional means to transmit at least one HARQ-ACK for the scheduled Msg4 transmission.

[0110] In some example embodiments, the second device 120 may receive from the user equipment an indication of the user equipment's ability to support at least one HARQ-ACK repetition for a scheduled Msg4 transmission. At least one reserved bit may be multiplexed based on the indicated capability.

[0111] In some example embodiments, the repetition factor can be indicated via a field in the DCI message, wherein when the field is not present in the DCI message, at least one reserved bit can be extended to be used as a backoff bit(s).

[0112] In some example embodiments, fields in a DCI message may be absent in response to one or more of the following: no repetition factor is configured; a repetition factor is configured for at least one HARQ-ACK; and the device does not support the ability to repeat for at least one HARQ-ACK.

[0113] In some example embodiments, the HARQ-ACK of the scheduled Msg4 transmission can be received via the Physical Uplink Control Channel (PUCCH).

[0114] Example devices, equipment and media In some example embodiments, a first means capable of performing any of the methods in method 400 (e.g., Figure 1 The first device 110 may include a component for performing the corresponding operation of method 400. This component may be implemented in any suitable form. For example, the component may be implemented in a circuit or software module. The first device may be implemented as or included in... Figure 1 In the first device 110.

[0115] In some example embodiments, the first apparatus includes: components for receiving downlink control information (DCI) messages from a network element, the DCI messages being scheduled as message 4 (Msg4) transmissions to the first apparatus during a random access procedure; and components for receiving scheduled Msg4 transmissions from the network element based on the DCI messages on a scheduled physical downlink shared channel (PDSCH) for performing the random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0116] In some example embodiments, at least one reserved bit is multiplexed as an indicator of the repetition factor, which is used to transmit at least one HARQ-ACK in response to a scheduled Msg4 transmission.

[0117] In some example embodiments, the first device includes: a component for receiving from a network element a configuration for a plurality of repetition factors, the plurality of repetition factors being available for at least one HARQ-ACK for a scheduled Msg4 transmission, wherein the indicated repetition factor is selected from the plurality of repetition factors.

[0118] In some example embodiments, the first device includes: a component for transmitting an indication of a preference repetition factor to a network element, the preference repetition factor being used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission, wherein at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

[0119] In some example embodiments, the first apparatus includes: a component for transmitting a HARQ-ACK for a scheduled Msg4 transmission to a network unit based on determining that at least one reserved bit indicates that a preference repetition factor has not been applied, the HARQ-ACK having no repetition or having a predetermined number of repetitions.

[0120] In some example embodiments, at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, which is used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission.

[0121] In some example embodiments, the first means includes: a component for transmitting to a network element an indication of the ability to repeat at least one HARQ-ACK for a scheduled Msg4 transmission, wherein at least one reserved bit is multiplexed based on the indicated capability.

[0122] In some example embodiments, the repetition factor may be indicated via a field in the DCI message, wherein when the field is not present in the DCI message, at least one reserved bit may be extended to be used as a backoff bit(s).

[0123] In some example embodiments, a field in the DCI message is absent in response to one or more of the following: no repetition factor is configured; a repetition factor is configured for at least one HARQ-ACK of the scheduled Msg4 transmission; the first device does not have the capability to support repetition of at least one HARQ-ACK for the scheduled Msg4 transmission.

[0124] In some example embodiments, at least one HARQ-ACK for a scheduled Msg4 transmission is transmitted via the Physical Uplink Control Channel (PUCCH).

[0125] In some example embodiments, the first device also includes components for performing other operations in some example embodiments of method 400 or the first device 110. In some example embodiments, the device includes at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first device to perform.

[0126] In some example embodiments, a second means capable of performing any of the methods in method 500 (e.g., Figure 1 The second device 120 may include components for performing the corresponding operations of method 500. This device may be implemented in any suitable form. For example, the device may be implemented in a circuit or software module. The second device may be implemented as or included in... Figure 1 The second device 120 in the middle.

[0127] In some example embodiments, the second apparatus includes components for scheduling a downlink control information (DCI) message to the user equipment for transmitting a message 4 (Msg4) to the user equipment on a scheduled physical downlink shared channel (PDSCH); and components for performing the scheduled Msg4 transmission to the user equipment during a random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, which will be used by the user equipment to transmit at least one hybrid automatic repeat request acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

[0128] In some example embodiments, at least one reserved bit is multiplexed as an indicator of the repetition factor, which will be used to transmit at least one HARQ-ACK in response to a scheduled Msg4 transmission.

[0129] In some example embodiments, the second means includes: a component for transmitting to a user equipment a configuration for a plurality of repetition factors, the plurality of repetition factors being available for at least one HARQ-ACK for a scheduled Msg4 transmission, wherein the indicated repetition factor is selected from the plurality of repetition factors.

[0130] In some example embodiments, the second apparatus includes: a component for receiving an indication of a preference repetition factor from a user equipment, the preference repetition factor being used to transmit at least one HARQ-ACK for a scheduled Msg4 transmission, wherein at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

[0131] In some example embodiments, at least one reserved bit indicates that a preference repetition factor is not applied, and at least one memory and a second means include: a component for receiving at least one HARQ-ACK from a user equipment for a scheduled Msg4 transmission, wherein the at least one HARQ-ACK has no repetition or has a predetermined number of repetitions.

[0132] In some example embodiments, at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, which will be used by additional means to transmit at least one HARQ-ACK for the scheduled Msg4 transmission.

[0133] In some example embodiments, the second means includes: a component for receiving from the user equipment an indication of the user equipment's ability to support at least one HARQ-ACK repeat for a scheduled Msg4 transmission, wherein at least one reserved bit is multiplexed based on the indicated capability.

[0134] In some example embodiments, the repetition factor is indicated via a field in the DCI message, wherein when the field is not present in the DCI message, at least one reserved bit is expanded to serve as a backoff bit(s).

[0135] In some example embodiments, a field in the DCI message is absent in response to one or more of the following: no repeat factor is configured; a repeat factor is configured for at least one HARQ-ACK; and the second device does not support the ability to repeat for at least one HARQ-ACK.

[0136] In some example embodiments, the HARQ-ACK of the scheduled Msg4 transmission is received via the Physical Uplink Control Channel (PUCCH).

[0137] In some example embodiments, the second device further includes components for performing other operations in some example embodiments of method 500 or the second device 120. In some example embodiments, the device includes at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second device to perform.

[0138] Figure 6 This is a simplified block diagram of a device 600 suitable for implementing an example embodiment of the present disclosure. Device 600 may be provided to implement a communication device, such as... Figure 1 The first device 110 or the second device 120 shown in the figure. As shown, device 600 includes one or more processors 610, one or more memories 620 coupled to processor 610, and one or more communication modules 640 coupled to processor 610.

[0139] Communication module 640 is used for bidirectional communication. Communication module 640 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interface can represent any interface necessary for communicating with other network units. In some example embodiments, communication module 640 may include at least one antenna.

[0140] As a non-limiting example, processor 610 can be any type suitable for a local technology network and can include one or more of the following: general-purpose computer, special-purpose computer, microprocessor, digital signal processor (DSP), and processor based on a multi-core processor architecture. Device 600 can have multiple processors, such as application-specific integrated circuit chips that are time-dependent on a clock of a synchronous main processor.

[0141] Memory 620 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 624, electrically programmable read-only memory (EPROM), flash memory, hard disk, optical disc (CD), digital video disc (DVD), optical disc, laser disc, and other magnetic and / or optical storage. Examples of volatile memories include, but are not limited to, random access memory (RAM) 622 and other volatile memories that may not persist during a power outage.

[0142] Computer program 630 includes computer-executable instructions that are executed by an associated processor 610. The instructions of program 630 may include instructions for performing operations / actions of some example embodiments of this disclosure. Program 630 may be stored in memory, such as ROM 624. Processor 610 can perform any suitable actions and processes by loading program 630 into RAM 622.

[0143] Example embodiments of this disclosure can be implemented by means of program 630, enabling device 600 to perform as described in the reference. Figures 1 to 5 Any process discussed in this disclosure. Exemplary embodiments of this disclosure may also be implemented in hardware or a combination of software and hardware.

[0144] In some example embodiments, program 630 may be tangibly contained in a computer-readable medium, which may be included in device 600 (such as in memory 620) or other storage devices accessible to device 600. Device 600 may load program 630 from the computer-readable medium into RAM 622 for execution. In some example embodiments, the computer-readable medium may include any type of non-transitory storage medium, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. As used herein, the term "non-transitory" refers to a limitation on the medium itself (i.e., tangible, not tactile), rather than a limitation on the persistence of data storage (e.g., RAM versus ROM).

[0145] Figure 7 An example of a computer-readable medium 700, which may be in the form of a CD, DVD, or other optical storage disc, is shown. A program 630 is stored on the computer-readable medium 700.

[0146] In general, the various embodiments of this disclosure can be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while others may be implemented in firmware or software executable by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of this disclosure are shown and described as block diagrams, flowcharts, or using some other graphical representation, it should be understood that, as non-limiting examples, the blocks, apparatuses, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof.

[0147] Some exemplary embodiments of this disclosure also provide at least one computer program product tangibly stored on a computer-readable medium, such as a non-transitory computer-readable medium. The computer program product includes computer-executable instructions, such as those included in a program module that executes in a device on a target physical or virtual processor, to perform any of the methods described above. Typically, a program module includes routines, programs, libraries, objects, classes, components, data structures, etc., that perform a particular task or implement a particular abstract data type. In various embodiments, the functionality of a program module can be combined or split among program modules as needed. The machine-executable instructions for a program module can execute within a local or distributed device. In a distributed device, the program module can reside on both local and remote storage media.

[0148] The program code used to perform the methods of this disclosure may be written in any combination of one or more programming languages. The 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 when executed by the processor or controller, the program code enables the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a stand-alone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0149] In the context of this disclosure, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, etc.

[0150] Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable media can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any suitable combination thereof. More specific examples of computer-readable storage media will include electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable optical disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0151] Furthermore, although operations are described in a specific order, this should not be construed as requiring such operations to be performed in the specific order shown or sequentially, or to perform all shown operations to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the above discussion, these details should not be construed as limiting the scope of this disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated otherwise, certain features described in the context of a single embodiment may also be implemented in combination in a single embodiment. Conversely, unless explicitly stated otherwise, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0152] Although this disclosure has been described in language specific to structural features and / or methodological actions, it should be understood that the disclosure as defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as exemplary forms for implementing the claims.

Claims

1. An apparatus comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the device to at least: The device receives downlink control information (DCI) messages from the network unit, the DCI messages being scheduled to be transmitted to message 4 (Msg4) during the random access procedure. as well as Based on the DCI message, a scheduled Msg4 transmission is received from the network element on the scheduled Physical Downlink Shared Channel (PDSCH) for performing the random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

2. The apparatus of claim 1, wherein the at least one reserved bit is multiplexed as an indicator repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK in response to the scheduled Msg4 transmission.

3. The apparatus of claim 2, wherein the at least one memory and the at least one processor further enable the apparatus to: Receive configuration for multiple repetition factors from the network element, the multiple repetition factors being usable for at least one HARQ-ACK for the scheduled Msg4 transmission. The indicated repeating factor is selected from the plurality of repeating factors.

4. The apparatus of claim 1, wherein the at least one memory and the at least one processor further enable the apparatus to: An indication of a preference repetition factor is transmitted to the network element, the preference repetition factor being used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

5. The apparatus of claim 4, wherein the at least one memory and the at least one processor further enable the apparatus to: Based on the determination that the at least one reserved bit indicates that the preference repetition factor has not been applied, the HARQ-ACK for the scheduled Msg4 transmission is transmitted to the network unit, the HARQ-ACK having no repetition or having a predetermined number of repetitions.

6. The apparatus of claim 1, wherein the at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission.

7. The apparatus according to any one of claims 1 to 6, wherein the at least one memory and the at least one processor further enable the apparatus to: The network element is informed of its ability to support the repetition of at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is reused based on the indicated capability.

8. The apparatus according to any one of claims 1 to 7, wherein the repetition factor is indicated via a field in the DCI message, wherein when the field is not present in the DCI message, the at least one reserved bit is expanded to serve as one or more backoff bits.

9. The apparatus of claim 8, wherein the field in the DCI message is absent in response to one or more of the following: No repeat factor was configured; A repetition factor is configured for the at least one HARQ-ACK for the scheduled Msg4 transmission; and The device does not support the repetition of the at least one HARQ-ACK for the scheduled Msg4 transmission.

10. The apparatus according to any one of claims 1 to 9, wherein the at least one HARQ-ACK for the scheduled Msg4 transmission is transmitted via the Physical Uplink Control Channel (PUCCH).

11. An apparatus comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the device to at least: Prior to scheduling message 4 (Msg4) to the user equipment on the scheduled physical downlink shared channel (PDSCH), downlink control information (DCI) messages are transmitted to the user equipment. as well as During a random access procedure, a scheduled Msg4 transmission is performed to the user equipment, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, which is to be used by the user equipment to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

12. The apparatus of claim 11, wherein the at least one reserved bit is multiplexed as an indicator repetition factor to be used to transmit the at least one HARQ-ACK in response to a scheduled Msg4 transmission.

13. The apparatus of claim 12, wherein the at least one memory and the at least one processor further enable the apparatus to: The configuration for multiple repetition factors is transmitted to the user equipment, the multiple repetition factors being usable for at least one HARQ-ACK for the scheduled Msg4 transmission. The indicated repeating factor is selected from the plurality of repeating factors.

14. The apparatus of claim 11, wherein the at least one memory and the at least one processor further enable the apparatus to: The user equipment receives an indication of a preference repetition factor, which is used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

15. The apparatus of claim 14, wherein the at least one reserved bit indicates that the preference repetition factor is not applied, and the at least one memory and the at least one processor further enable the apparatus to: The user equipment receives at least one HARQ-ACK for the scheduled Msg4 transmission, wherein the at least one HARQ-ACK has no repetitions or has a predetermined number of repetitions.

16. The apparatus of claim 11, wherein the at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, the repetition factor being used by the additional apparatus to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission.

17. The apparatus according to any one of claims 11 to 16, wherein the at least one memory and the at least one processor further enable the apparatus to: Receive from the user equipment an indication of the user equipment's ability to support at least one HARQ-ACK repetition for the scheduled Msg4 transmission. The at least one reserved bit is reused based on the indicated capability.

18. The apparatus according to any one of claims 11 to 17, wherein the repetition factor is indicated via a field in the DCI message, wherein when the field is not present in the DCI message, the at least one reserved bit is expanded to serve as one or more backoff bits.

19. The apparatus of claim 18, wherein the field in the DCI message is absent in response to one or more of the following: No repeat factor was configured; A repetition factor is configured for the at least one HARQ-ACK; and The device does not support the ability to repeat the at least one HARQ-ACK.

20. The apparatus according to any one of claims 11 to 19, wherein the HARQ-ACK transmitted by the scheduled Msg4 is received via the Physical Uplink Control Channel (PUCCH).

21. A method comprising: Receive downlink control information (DCI) messages from network units, the DCI messages being scheduled for message 4 (Msg4) transmission during the random access procedure; as well as Based on the DCI message, a scheduled Msg4 transmission is received from the network element on the scheduled Physical Downlink Shared Channel (PDSCH) for performing the random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

22. The method of claim 21, wherein the at least one reserved bit is multiplexed as an indicator repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK in response to the scheduled Msg4 transmission.

23. The method of claim 22, wherein the at least one memory and the at least one processor further cause the first device to perform: Receive configuration for multiple repetition factors from the network element, the multiple repetition factors being usable for at least one HARQ-ACK for the scheduled Msg4 transmission. The indicated repeating factor is selected from the plurality of repeating factors.

24. The method of claim 21, wherein the at least one memory and the at least one processor further cause the first device to perform: An indication of a preference repetition factor is transmitted to the network element, the preference repetition factor being used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

25. The method of claim 24, wherein the at least one memory and the at least one processor further cause the first device to perform: Based on the determination that the at least one reserved bit indicates that the preference repetition factor has not been applied, the HARQ-ACK for the scheduled Msg4 transmission is transmitted to the network unit, the HARQ-ACK having no repetition or having a predetermined number of repetitions.

26. The method of claim 21, wherein the at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission.

27. The method according to any one of claims 21 to 26, wherein the at least one memory and the at least one processor further cause the first means to perform: The network element is informed of its ability to support the repetition of at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is reused based on the indicated capability.

28. The method of any one of claims 21 to 27, wherein the repetition factor is indicated via a field in the DCI message, wherein when the field is not present in the DCI message, the at least one reserved bit is expanded to serve as one or more backoff bits.

29. The method of claim 28, wherein the field in the DCI message is absent in response to one or more of the following: No repeat factor was configured; A repetition factor is configured for the at least one HARQ-ACK for the scheduled Msg4 transmission; and The first device does not support the repetition of the at least one HARQ-ACK for the scheduled Msg4 transmission.

30. The method according to any one of claims 21 to 29, wherein the at least one HARQ-ACK for the scheduled Msg4 transmission is transmitted via the Physical Uplink Control Channel (PUCCH).

31. A method comprising: Prior to the scheduled transmission of message 4 (Msg4) to the user equipment on the scheduled physical downlink shared channel (PDSCH), downlink control information (DCI) is transmitted to the user equipment. as well as During a random access procedure, a scheduled Msg4 transmission is performed to the user equipment, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, which will be used by the user equipment to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

32. The method of claim 31, wherein the at least one reserved bit is multiplexed as an indicator repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK in response to a scheduled Msg4 transmission.

33. The method of claim 32, wherein the at least one memory and the at least one processor further cause the second means to perform: The configuration for multiple repetition factors is transmitted to the user equipment, and these multiple repetition factors can be used for at least one HARQ-ACK for the scheduled Msg4 transmission. The indicated repeating factor is selected from the plurality of repeating factors.

34. The method of claim 31, wherein the at least one memory and the at least one processor further cause the second means to perform: The user equipment receives an indication of a preference repetition factor, which is used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

35. The method of claim 34, wherein the at least one reserved bit indicates that the preference repetition factor has not been applied, and the at least one memory and the at least one processor further cause the second means to perform: Receive at least one HARQ-ACK from the user equipment for the scheduled Msg4 transmission, wherein the HARQ-ACK has no repetitions or has a predetermined number of repetitions.

36. The method of claim 31, wherein the at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, the repetition factor being used by the additional second means to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission.

37. The method according to any one of claims 31 to 36, wherein the at least one memory and the at least one processor further cause the second means to perform: Receive from the user equipment an indication of the user equipment's ability to support at least one HARQ-ACK repetition for the scheduled Msg4 transmission. The at least one reserved bit is reused based on the indicated capability.

38. The method of any one of claims 31 to 37, wherein the repetition factor is indicated via a field in the DCI message, wherein when the field is not present in the DCI message, the at least one reserved bit is expanded to serve as one or more backoff bits.

39. The method of claim 38, wherein the field in the DCI message is absent in response to one or more of the following: No repeat factor was configured; A repetition factor is configured for the at least one HARQ-ACK; and The second device supports the ability to repeat the at least one HARQ-ACK.

40. The method according to any one of claims 31 to 39, wherein the HARQ-ACK of the scheduled Msg4 transmission is received via the Physical Uplink Control Channel (PUCCH).

41. An apparatus comprising: A component for receiving downlink control information (DCI) messages from a network unit, the DCI messages being scheduled to be transmitted to the first device as message 4 (Msg4) during a random access procedure. as well as A component for receiving a scheduled Msg4 transmission from the network element on a scheduled physical downlink shared channel (PDSCH) for performing the random access procedure based on the DCI message, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, the repetition factor being used to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

42. The apparatus of claim 41, wherein the at least one reserved bit is multiplexed as an indicator repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK in response to the scheduled Msg4 transmission.

43. The apparatus of claim 42, comprising: Components for receiving configurations for multiple repetition factors from the network element, the multiple repetition factors being usable for at least one HARQ-ACK for the scheduled Msg4 transmission. The indicated repeating factor is selected from the plurality of repeating factors.

44. The apparatus of claim 41, comprising: A component for transmitting an indication of a preference repetition factor to the network element, the preference repetition factor being used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

45. The apparatus of claim 44, comprising: A component for transmitting the HARQ-ACK for the scheduled Msg4 transmission to the network unit based on determining that the preference repetition factor has not been applied by at least one reserved bit, wherein the HARQ-ACK has no repetition or has a predetermined number of repetitions.

46. ​​The apparatus of claim 41, wherein the at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission.

47. The apparatus according to any one of claims 41 to 46, comprising: A component for transmitting to the network element an indication of the ability to repeat at least one HARQ-ACK for the scheduled Msg4 transmission. The at least one reserved bit is reused based on the indicated capability.

48. The apparatus according to any one of claims 41 to 47, wherein the repetition factor is indicated via a field in the DCI message, wherein when the field is not present in the DCI message, the at least one reserved bit is expanded to serve as one or more backoff bits.

49. The apparatus of any one of claims 48, wherein the field in the DCI message is absent in response to one or more of the following: No repeat factor was configured; A repetition factor is configured for the at least one HARQ-ACK for the scheduled Msg4 transmission; and The first device does not support the repetition of the at least one HARQ-ACK for the scheduled Msg4 transmission.

50. The apparatus according to any one of claims 41 to 49, wherein the at least one HARQ-ACK for the scheduled Msg4 transmission is transmitted via the Physical Uplink Control Channel (PUCCH).

51. An apparatus comprising: A component for transmitting downlink control information (DCI) messages to the user equipment prior to the scheduled transmission of message 4 (Msg4) to the user equipment on the scheduled physical downlink shared channel (PDSCH); as well as A component for performing a scheduled Msg4 transmission to the user equipment during a random access procedure, wherein at least one reserved bit in the DCI message is multiplexed in association with an indication of a repetition factor, which will be used by the user equipment to transmit at least one Hybrid Automatic Repeat Request Acknowledgment (HARQ-ACK) for the scheduled Msg4 transmission.

52. The apparatus of claim 51, wherein the at least one reserved bit is multiplexed as an indicator repetition factor, the repetition factor being used to transmit the at least one HARQ-ACK in response to a scheduled Msg4 transmission.

53. The apparatus of claim 51, wherein the second apparatus comprises: Components for transmitting to the user equipment a configuration for a plurality of repetition factors, the plurality of repetition factors being available for the at least one HARQ-ACK for a scheduled Msg4 transmission, wherein the indicated repetition factor is selected from the plurality of repetition factors.

54. The apparatus of claim 51, wherein the second apparatus comprises: A component for receiving an indication of a preference repetition factor from the user equipment, the preference repetition factor being used to transmit at least one HARQ-ACK for the scheduled Msg4 transmission, wherein the at least one reserved bit is multiplexed to indicate whether the preference repetition factor is applied.

55. The apparatus of claim 54, wherein the at least one reserved bit indicates that the preference repetition factor has not been applied, and the at least one memory and the second apparatus comprise: A component for receiving at least one HARQ-ACK from the user equipment for a scheduled Msg4 transmission, wherein the at least one HARQ-ACK has no repetitions or has a predetermined number of repetitions.

56. The apparatus of claim 51, wherein the at least one reserved bit is multiplexed to indicate whether at least one field in the DCI message is multiplexed to indicate a repetition factor, the repetition factor being used by the additional apparatus to transmit the at least one HARQ-ACK for the scheduled Msg4 transmission.

57. The apparatus according to any one of claims 51 to 56, wherein the second apparatus comprises: A component for receiving from the user equipment an indication of the user equipment's ability to support at least one HARQ-ACK repetition for a scheduled Msg4 transmission, wherein the at least one reserved bit is multiplexed based on the indicated capability.

58. The apparatus according to any one of claims 51 to 57, wherein the repetition factor is indicated via a field in the DCI message, wherein when the field is not present in the DCI message, the at least one reserved bit is expanded to serve as one or more backoff bits.

59. The apparatus of claim 58, wherein the field in the DCI message is absent in response to one or more of the following: no repetition factor is configured; a repetition factor is configured for the at least one HARQ-ACK; and the second apparatus does not support the ability to repeat for the at least one HARQ-ACK.

60. The apparatus according to any one of claims 51 to 59, wherein the HARQ-ACK transmitted by the scheduled Msg4 is received via the Physical Uplink Control Channel (PUCCH).

61. A computer-readable medium comprising instructions stored thereon, the instructions being configured to cause a device to perform at least the method according to any one of claims 21 to 30 or the method according to any one of claims 31 to 40.

Images