Pdsch coverage enhancement in random access procedure

Abstract

A user equipment (UE) configured to operate in a fifth generation new radio (5G NR) network can perform a four-step random access (4-step RACH) procedure for initial access. The UE can decode a downlink control information (DCI) format for scheduling a message 4 (Msg4) physical downlink shared channel (PDSCH) transmission. To achieve coverage enhancement in the initial access procedure, the UE can decode repeated transmissions of the Msg4 PDSCH transmission received from a gNB according to the scheduling. The repetitions of the Msg4 PDSCH transmission can be configured to the UE by means of higher layer signaling and / or signaled to the UE by means of a field in the DCI format. To communicate with the gNB via a non-terrestrial network (NTN), the DCI format and the Msg4 PDSCH transmission are received from the gNB via the NTN. When the UE communicates with the gNB via the NTN, the Msg4 PDSCH transmission can be repeatedly transmitted to achieve coverage enhancement.

Description

[0001] Priority requirements This application claims priority to U.S. Provisional Patent Application No. 63 / 574,023 (volume AG0399-Z), filed April 3, 2024, which is incorporated herein by reference in its entirety. Technical Field

[0002] The embodiments relate to wireless communications. Some embodiments relate to wireless networks including 3GPP (3rd Generation Partnership Project) and fifth-generation (5G) networks, which include 5G New Radio (NR) (or 5G-NR) networks. Some embodiments relate to sixth-generation (6G) networks. Background Technology

[0003] Mobile communications have evolved significantly from early voice systems into highly complex integrated communication platforms. The use of 3GPP 5G NR systems has also increased with the growing number of different types of devices communicating with various network devices. The increasing penetration of mobile devices (User Equipment) in modern society has continuously driven the demand for a wide variety of connected devices in many different environments. The upcoming 5G NR radio systems are expected to deliver higher speeds, connectivity, and availability, and are anticipated to increase throughput, coverage (range or coverage area), and robustness, while reducing latency, operating expenses, and capital expenditures. 5G-NR networks will continue to evolve on top of 3GPP LTE-Advanced, incorporating other potential New Radio Access Technologies (RATs) to enrich people's lives through seamless wireless connectivity solutions that provide fast, rich content, and services. Given the current saturation of cellular network frequencies, higher frequencies, such as millimeter wave (mmWave) frequencies, will be beneficial due to their high bandwidth.

[0004] One challenge in transmitting data over wireless networks is coverage. For cellular systems, coverage is a critical factor for successful operation. Compared to LTE, NR can be deployed at relatively higher carrier frequencies within Frequency Range 1 (FR1), such as 3.5 GHz. In this case, coverage loss is expected due to significant path loss, making it more challenging to maintain adequate quality of service. Typically, uplink coverage becomes a bottleneck for system operation, given the low transmit power at the UE side. This is particularly problematic for cellular systems using non-terrestrial networks (NTNs), where UEs receive service via satellite or high-altitude platform stations. Given the significant distance between the NTN and the UE, NTN deployments may require additional coverage enhancements. Attached Figure Description

[0005] Figure 1A The architecture of a network according to some embodiments is shown.

[0006] Figure 1B and Figure 1C A non-roaming 5G system architecture according to some embodiments is shown.

[0007] Figure 2 The four-step random access (4-step RACH) procedure performed for initial access according to some embodiments is shown.

[0008] Figure 3 The NTN-based NG Radio Access Network (RAN) and terrestrial NG-RAN are illustrated according to some embodiments.

[0009] Figure 4 A functional block diagram of a wireless communication device according to some embodiments is shown. Detailed Implementation

[0010] The following description and accompanying drawings fully illustrate specific embodiments that enable those skilled in the art to implement them. Other embodiments may include variations in structural, logical, electrical, technological, and other aspects. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The embodiments set forth in the claims cover all available equivalents of these claims.

[0011] The embodiments disclosed herein provide coverage enhancement for 5G NR systems. In some embodiments, such coverage enhancement may be applicable to NTN deployments; however, the scope of the embodiments is not limited thereto. In some embodiments, coverage enhancement is provided during the initial access process by repeatedly transmitting one or more messages via the NTN for initial access. In some embodiments, repeated transmission of Msg4PDSCH provides coverage enhancement during the initial access process via the NTN.

[0012] Some embodiments relate to a User Equipment (UE) configured to operate in a 5G New Radio (5G NR) network. To perform a four-step random access (4-step RACH) procedure for initial access, the UE may encode the Physical Uplink Shared Channel (PUSCH) transmission of Message 3 (Msg3) sent to the g Node B (gNB). The UE may also decode the Downlink Control Information (DCI) format used to schedule the Physical Downlink Shared Channel (PDSCH) transmission of Message 4 (Msg4). To achieve coverage enhancement during initial access, the UE may decode the retransmission of Msg4 PDSCH transmissions received from the gNB according to scheduling. In these embodiments, the retransmission of Msg4 PDSCH transmissions may be configured to the UE by means of higher-layer signaling or signaled to the UE by means of fields in the DCI format. In these embodiments, the retransmission of Msg4 PDSCH transmissions provides coverage enhancement during initial access. In these embodiments, the retransmission of Msg4 PDSCH transmissions provides coverage enhancement during initial access via the NTN. These and other embodiments are discussed in more detail here.

[0013] Some embodiments involve a gNode B (gNB) configured to operate in a 5G New Radio (NR) network. To utilize a User Equipment (UE) to perform a four-step random access (4-step RACH) procedure for initial access, the gNB can decode the Physical Uplink Shared Channel (PUSCH) transmission of Message 3 (Msg3) from the UE and encode the Downlink Control Information (DCI) format for scheduling the Physical Downlink Shared Channel (PDSCH) transmission of Message 4 (Msg4). In these embodiments, the gNB can encode the retransmission of the Msg4 PDSCH transmission sent to the UE according to scheduling. In these embodiments, the retransmission of the Msg4 PDSCH transmission can be configured to the UE by means of higher-layer signaling and / or signaled to the UE by means of fields in the DCI format.

[0014] Figure 1A An architecture of a network according to some embodiments is illustrated. Network 140A is shown as including user equipment (UE) 101 and UE 102. UE 101 and UE 102 are shown as smartphones (e.g., handheld touchscreen mobile computing devices capable of connecting to one or more cellular networks), but may also include any mobile or non-mobile computing device, such as a personal data assistant (PDA), pager, laptop computer, desktop computer, wireless phone, drone, or any other computing device including wired and / or wireless communication interfaces. UE 101 and UE 102 may be collectively referred to herein as UE 101 or UE 102, and UE 101 and / or UE 102 may be used to perform one or more of the techniques disclosed herein.

[0015] According to embodiments, UE 101 and / or UE 102 can be configured to operate in a 5G New Radio (5G NR) network. To perform a four-step random access (4-step RACH) procedure for initial access, the UE can encode the Physical Uplink Shared Channel (PUSCH) transmission of Message 3 (Msg3) sent to the g Node B (gNB). The UE can also decode the Downlink Control Information (DCI) format used to schedule the Physical Downlink Shared Channel (PDSCH) transmission of Message 4 (Msg4). To achieve coverage enhancement during initial access, the UE can decode the retransmission of Msg4 PDSCH transmissions received from the gNB according to scheduling. In these embodiments, the retransmission of Msg4 PDSCH transmissions can be configured to the UE by means of higher-layer signaling and / or signaled to the UE by means of fields in the DCI format. In these embodiments, the retransmission of Msg4 PDSCH transmissions provides coverage enhancement during initial access.

[0016] Any wireless link described herein (e.g., used in network 140A or any other network shown) may operate according to any exemplary wireless communication technology and / or standard.

[0017] LTE and LTE Advanced are standards for high-speed data wireless communication for UEs, such as mobile phones. In LTE Advanced and various wireless systems, carrier aggregation is a technique that uses multiple carrier signals operating at different frequencies to carry communication for a single UE, thereby increasing the bandwidth available to a single device. In some embodiments, carrier aggregation can be used when one or more component carriers operate at unlicensed frequencies.

[0018] The embodiments described herein can be used in any spectrum management scenario, including, for example, dedicated licensed spectrum, unlicensed spectrum, and (licensed) shared spectrum (e.g., licensed shared access (LSA) in 2.3 GHz - 2.4 GHz, 3.4 GHz - 3.6 GHz, 3.6 GHz - 3.8 GHz and other frequencies, and spectrum access systems (SAS) in 3.55 GHz - 3.7 GHz and other frequencies).

[0019] The embodiments described herein can also be applied to different single-carrier or OFDM modes (CP-OFDM, SC-FDMA, SC-OFDM, filter bank-based multicarrier (FBMC), OFDMA, etc.), especially 3GPP NR (New Radio), by allocating OFDM carrier data bit vectors (bit vectors) to corresponding symbol resources.

[0020] In some embodiments, either UE 101 or UE 102 may include an Internet of Things (IoT) UE or a Cellular IoT (CIoT) UE, which may include a network access layer designed for low-power IoT applications utilizing short-lived UE connectivity. In some embodiments, either UE 101 or UE 102 may include a narrowband (NB) IoT UE (e.g., enhanced NB-IoT (eNB-IoT) UE and further enhanced (FeNB-IoT) UE). The IoT UE may utilize technologies such as machine-to-machine (M2M) or machine-type communication (MTC) to exchange data with an MTC server or device via a Public Land Mobile Network (PLMN), Proximity-Based Service (ProSe) or Device-to-Device (D2D) communication, sensor networks, or IoT networks. M2M or MTC data exchange may be machine-initiated data exchange. The IoT network includes IoT UEs interconnected using short-lived connectivity, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure). The IoT UE may execute background applications (e.g., keeping messages active, status updates, etc.) to facilitate connectivity within the IoT network.

[0021] In some embodiments, either UE 101 or UE 102 may include an enhanced MTC (eMTC) UE or a further enhanced MTC (FeMTC) UE.

[0022] UE 101 and UE 102 can be configured to connect to, for example, a radio access network (RAN) 110 for communication coupling. RAN 110 can be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), a Next Generation RAN (NGRAN), or some other type of RAN. UE 101 and UE 102 utilize connection 103 and connection 104 respectively, each of which includes a physical communication interface or physical communication layer (discussed in further detail below); in this example, connection 103 and connection 104 are shown as air interfaces for implementing communication coupling and can conform to cellular communication protocols, including, for example, the Global System for Mobile Communications (GSM) protocol, Code Division Multiple Access (CDMA) network protocol, Push-to-Talk (PTT) protocol, Cellular PTT (POC) protocol, Universal Mobile Telecommunications System (UMTS) protocol, 3GPP Long Term Evolution (LTE) protocol, 5G protocol, New Radio (NR) protocol, etc.

[0023] On the other hand, UE 101 and UE 102 can also directly exchange communication data via ProSe interface 105. ProSe interface 105 can be alternatively referred to as a sidelink interface including one or more logical channels, including but not limited to the Physical Sidelink Control Channel (PSCCH), Physical Sidelink Shared Channel (PSSCH), Physical Sidelink Discovery Channel (PSDCH), and Physical Sidelink Broadcast Channel (PSBCH).

[0024] UE 102 is shown and configured to access access point (AP) 106 via connection 107. For example, connection 107 may include a local wireless connection, such as a connection conforming to any IEEE 802.11 protocol, according to which AP 106 may include a Wi-Fi router. In this example, AP 106 is shown connected to the Internet but not to the core network of the wireless system (described in further detail below).

[0025] RAN 110 may include one or more access nodes that implement connections 103 and 104. These access nodes (ANs) may be referred to as base stations (BS), Node Bs, evolved Node Bs (eNBs), next-generation Node Bs (gNBs), RAN nodes, etc., and may include ground stations (e.g., ground access points) or satellite stations providing coverage within a geographic area (e.g., a cell). In some embodiments, RAN nodes 111 and RAN nodes 112 may be transmit / receive points (TRPs). When RAN nodes 111 and RAN nodes 112 are Node Bs (e.g., eNBs or gNBs), one or more TRPs are capable of operating within the communication cell of the Node B. RAN 110 may include one or more RAN nodes (e.g., macro RAN nodes) for providing macro cells and one or more RAN nodes (e.g., low-power (LP) RAN nodes) for providing femtocells or picocells (e.g., cells with smaller coverage areas, smaller user capacity, or higher bandwidth compared to macro cells).

[0026] RAN 110 may include a terrestrial network (TN) (i.e., terrestrial NG-RAN) and / or a non-terrestrial network (NTN) (i.e., NTN-based NG RAN). Figure 3 Examples of NTN-based NG RAN and terrestrial NG-RAN are shown in the figure.

[0027] Either RAN node 111 or RAN node 112 can terminate the air interface protocol and can serve as the first contact point for UE 101 and UE 102. In some embodiments, either RAN node 111 or RAN node 112 can implement various logical functions for RAN 110, including but not limited to Radio Network Controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management, data packet scheduling, and mobility management. In the example, either RAN node 111 and / or RAN node 112 can be a next-generation node B (gNB), an evolved Node B (eNB), or another type of RAN node.

[0028] RAN 110 is shown as communicatively coupled to core network (CN) 120 via S1 interface 113. In embodiments, CN 120 may be an evolved packet core (EPC) network, a next-generation packet core (NPC) network, or some other type of CN (e.g., as referenced). Figure 1B-1C (As shown). In this aspect, the S1 interface 113 is divided into two parts: the S1-U interface 114, which carries service data between RAN nodes 111 and RAN nodes 112 and the serving gateway (S-GW) 122; and the S1-MME interface 115, which is the signaling interface between RAN nodes 111 and RAN nodes 112 and the MME 121.

[0029] In this respect, CN 120 includes MME 121, S-GW 122, Packet Data Network (PDN) Gateway (P-GW) 123, and Home Subscriber Server (HSS) 124. MME 121 can functionally resemble the control plane of a Legacy Service General Packet Radio Service (GPRS) Support Node (SGSN). MME 121 can manage mobility implementations in access, such as gateway selection and tracking area list management. HSS 124 can include a database for network users, containing subscription-related information to support network entities in handling communication sessions. Depending on the number of mobile users, equipment capacity, network organization, etc., CN 120 may include one or more HSS 124s. For example, HSS 124 can provide support for routing / roaming, authentication, authorization, naming / addressing resolution, location dependencies, etc.

[0030] The S-GW 122 can terminate the S1 interface 113 toward RAN 110 and route data packets between RAN 110 and CN 120. Additionally, the S-GW 122 can serve as a local mobility anchor for inter-RAN node handover and can also provide an anchor for inter-3GPP mobility. Other responsibilities of the S-GW 122 may include lawful interception (blocking), billing, and some policy enforcement.

[0031] P-GW 123 can terminate an SGi interface toward the PDN. P-GW 123 can route data packets between CN 120 and external networks, such as a network including application server 184 (alternatively referred to as Application Function (AF)), via Internet Protocol (IP) interface 125. P-GW 123 can also transmit data to other external networks 131A, which may include the Internet, IP Multimedia Subsystem (IPS) networks, and other networks. Generally, application server 184 can be an element providing applications that use IP bearer resources with the core network (e.g., UMTS Packet Service (PS) domain, LTE PS Data Service, etc.). In this respect, P-GW 123 is shown communicatively coupled to application server 184 via IP interface 125. Application server 184 can also be configured to support one or more communication services (e.g., Voice over Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for UE 101 and UE 102 via CN 120.

[0032] P-GW 123 can also be a node for policy enforcement and charging data collection. The Policy and Charging Rule Function (PCRF) 126 is the policy and charging control element of CN 120. In some embodiments, in non-roaming scenarios, a single PCRF may exist in the Home Public Land Mobile Network (HPLMN) associated with the UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In roaming scenarios with local service branches, two PCRFs associated with the UE's IP-CAN session may exist: the Home PCRF (H-PCRF) within the HPLMMN and the Visited PCRF (V-PCRF) within the Visited Public Land Mobile Network (VPLMN). PCRF 126 may be communicatively coupled to application server 184 via P-GW 123.

[0033] In some embodiments, the communication network 140A may be an IoT network or a 5G network, which includes a 5G New Radio network using licensed (5G NR) and unlicensed (5G NR-U) spectrum for communication. One of the current enabling technologies (implementations) for the Internet of Things (IoT) is Narrowband Internet of Things (NB-IoT).

[0034] The NG system architecture may include a RAN 110 and a 5G network core (5GC). In these embodiments, the RAN 110 may include multiple nodes such as gNBs and NG-eNBs. The CN 120 (e.g., a 5G core network or 5GC) may include Access and Mobility Functions (AMF) and / or User Plane Functions (UPF). The AMF and UPF may be communicatively coupled to the gNBs and NG-eNBs via NG interfaces. More specifically, in some embodiments, the gNBs and NG-eNBs may be connected to the AMF via an NG-C interface and to the UPF via an NG-U interface. The gNBs and ng-eNBs may be coupled to each other via Xn interfaces.

[0035] In some embodiments, the NG system architecture may use various reference points between nodes as provided in 3GPP Technical Specification (TS) 23.501 (e.g., V15.4.0, 2018-12). In some embodiments, each of the gNB and NG-eNB may be implemented as a base station, a mobile edge server, a small cell, a home eNB, etc. In some embodiments, the gNB may be the master node (MN) in a 5G architecture, and the NG-eNB may be the secondary node (SN).

[0036] Figure 1B A non-roaming 5G system architecture according to some embodiments is illustrated. (Reference) Figure 1B The 5G system architecture 140B is illustrated using reference point notation. More specifically, UE 102 can communicate with RAN 110 and one or more other 5G core (5GC) network entities. The 5G system architecture 140B includes multiple network functions (NFs), such as Access and Mobility Management Function (AMF) 132, Session Management Function (SMF) 136, Policy Control Function (PCF) 148, Application Function (AF) 150, User Plane Function (UPF) 134, Network Slice Selection Function (NSSF) 142, Authentication Server Function (AUSF) 144, and Unified Data Management (UDM) / Home Subscriber Server (HSS) 146. UPF 134 can provide connectivity to a data network (DN) 152, which may include, for example, operator services, internet access, or third-party services. AMF 132 can be used to manage access control and mobility, and may also include network slice selection functionality. SMF 136 can be configured to establish and manage various sessions according to network policies. UPF 134 can be deployed in one or more configurations depending on the desired service type. PCF 148 can be configured to provide a policy framework using network slicing, mobility management, and roaming (similar to PCRF in 4G communication systems). UDM can be configured to store user profiles and data (similar to HSS in 4G communication systems).

[0037] In some embodiments, the 5G system architecture 140B includes an IP Multimedia Subsystem (IMS) 168B and multiple IP Multimedia Core Network Subsystem entities, such as a Call Session Control Function (CSCF). More specifically, the IMS 168B includes a CSCF that can act as a proxy CSCF (P-CSCF) 162B, a serving CSCF (S-CSCF) 164B, and an emergency CSCF (E-CSCF). Figure 1B (Not shown in the image) or query the CSCF (I-CSCF) 166B. The P-CSCF 162B can be configured as the first contact point for UE 102 within the IM subsystem (IMS) 168B. The S-CSCF 164B can be configured to handle session states in the network, and the E-CSCF can be configured to handle specific implementations of emergency sessions, such as routing emergency requests to the correct emergency center or PSAP. The I-CSCF 166B can be configured as a contact point within the operator's network for all IMS connections whose destination is a user of that network operator or a roaming user currently within the service area of ​​that network operator. In some embodiments, the I-CSCF 166B can connect to another IP multimedia network 170E, such as an IMS operated by a different network operator.

[0038] In some embodiments, UDM / HSS 146 may be coupled to application server 160E, which may include a telephone application server (TAS) or another application server (AS). AS 160B may be coupled to IMS 168B via S-CSCF 164B or I-CSCF 166B.

[0039] Reference point notation indicates that interactions can exist between corresponding NF services. For example, Figure 1BThe following reference points are shown: N1 (between UE 102 and AMF 132), N2 (between RAN 110 and AMF 132), N3 (between RAN 110 and UPF 134), N4 (between SMF 136 and UPF 134), N5 (between PCF 148 and AF 150, not shown), N6 (between UPF 134 and DN 152), N7 (between SMF 136 and PCF 148, not shown), N8 (between UDM / HSS 146 and AMF 132, not shown), N9 (between the two UPF 134, not shown), N10 (between UDM / HSS 146 and SMF 136, not shown), N11 (between AMF 132 and SMF 134). N11 (between AMF 136, not shown), N12 (between AMF 144 and AMF 132, not shown), N13 (between AMF 144 and UDM / HSS 146, not shown), N14 (between two AMF 132, not shown), N15 (between PCF 148 and AMF 132 in non-roaming scenarios, or between PCF 148 and the visited network and AMF 132 in roaming scenarios, not shown), N16 (between two SMF 136, not shown), and N22 (between AMF 132 and NSSF 142, not shown). Alternatively, you can use... Figure 1B Other reference point representations not shown in the diagram.

[0040] Figure 1C The 5G system architecture 140C and its service-based representation are shown. Besides... Figure 1B In addition to the network entities shown, system architecture 140C may also include Network Open Function (NEF) 154 and Network Storage Function (NRF) 156. In some embodiments, the 5G system architecture may be service-based, and the interaction between network functions may be represented by corresponding point-to-point reference points Ni or as service-based interfaces.

[0041] In some embodiments, such as Figure 1CAs shown, service-based notation can be used to represent network functions within the control plane that enable other authorized network functions to access the services of those authorized network functions. In this regard, the 5G system architecture 140C may include the following service-based interfaces: Namf 158H (a service-based interface presented by AMF 132), Nsmf 158I (a service-based interface presented by SMF 136), Nnef158B (a service-based interface presented by NEF 154), Npcf 158D (a service-based interface presented by PCF 148), Nudm 158E (a service-based interface presented by UDM / HSS 146), Naf 158F (a service-based interface presented by AF 150), Nnrf 158C (a service-based interface presented by NRF 156), Nnssf 158A (a service-based interface presented by NSSF 142), and Nausf 158G (a service-based interface presented by AUSF 144). Alternatively, it can use... Figure 1C Other service-based interfaces not shown (e.g., Nudr, N5g-eir, and Nudsf).

[0042] In some embodiments, combined with Figures 1A to 1C Any UE or base station described herein can be configured to perform the functions described herein.

[0043] Mobile communications have evolved significantly from early voice systems into highly complex integrated communication platforms. Next-generation wireless communication systems, 5G systems, or New Radio (NR) systems, aim to provide access to information and data sharing for a wide range of users and applications. NR is envisioned as a unified network / system designed to meet diverse and sometimes conflicting performance dimensions and services. This diverse, multidimensional demand is driven by different services and applications. Generally, NR will evolve from 3GPP LTE Advanced and incorporate additional potential New Radio Access Technologies (RATs) to enrich people's lives with superior, simpler, and seamless wireless connectivity solutions. NR will support everything made possible by wireless connectivity and deliver fast, rich content and services.

[0044] Version 15 of the NR system was designed to operate on licensed spectrum. NR-Unlicensed (NR-U) is an abbreviation for NR-based unlicensed spectrum access, a technology that enables NR systems to operate on unlicensed spectrum.

[0045] In NR Release 15, a four-step procedure is defined for initial access. In the first step, the UE transmits the Physical Random Access Channel (PRACH) in the uplink (UL) by randomly selecting a preamble signature. This allows the gNB to estimate the delay between the gNB and the UE for subsequent UL timing adjustments. Subsequently, in the second step, the gNB sends back a Random Access Response (RAR), which carries timing advance (TA) command information and uplink grants for uplink transmission in the third step. The UE expects to receive the RAR within a time window, the start (start point) and end (end point) of which are configured by the gNB via a System Information Block (SIB). The UE then transmits Msg3 based on the uplink grant in the RAR. Msg3 may include the Physical Uplink Shared Channel (PUSCH). The gNB then transmits Msg4 for contention resolution.

[0046] For NTN deployments, it may be necessary to improve the coverage of Physical Downlink Shared Channel (PDSCH) transmissions during the 4-step RACH process and / or 2-step RACH process to meet target requirements. In this case, it may be necessary to define specific mechanisms to enhance the coverage of Msg2 PDSCH and Msg4 PDSCH transmissions during random access.

[0047] In some embodiments, PDSCH coverage enhancement is provided during random access. In some embodiments, Msg2 PDSCH coverage enhancement is provided for initial access. In some embodiments, Msg4 PDSCH coverage enhancement is provided for initial access. In some embodiments, conditions are provided for requesting Msg2 / Msg4 PDSCH repetition during random access.

[0048] For initial access, coverage enhancement of Msg2 PDSCH is implemented. As mentioned above, for NTN deployments, it may be necessary to improve the coverage of Physical Downlink Shared Channel (PDSCH) transmissions during the 4-step RACH process and / or 2-step RACH process to meet target requirements. In this case, it may be necessary to define specific mechanisms to enhance the coverage of Msg2 PDSCH and Msg4 PDSCH transmissions during the random access process. An example of enhancing Msg2 PDSCH coverage for initial access is described below.

[0049] In some embodiments, the UE may report its ability to support repeated transmission of Msg2 Physical Downlink Shared Channel (PDSCH), MsgB PDSCH, and / or Msg4 PDSCH to the gNB using Physical Random Access Channel (PRACH) resource allocation. In some embodiments, a set of PRACH resources may be configured (via SIB1) for the UE to indicate support for repeated transmission of Msg2 PDSCH, MsgB PDSCH, and / or Msg4 PDSCH. Similarly, the UE may send a request to the gNB to repeat Msg2 PDSCH, MsgB PDSCH, and / or Msg4 PDSCH transmissions using PRACH resource allocation.

[0050] In addition, the UE can use a separate PRACH preamble when sharing the PRACH timing (RO) or use a separate RO that is different from the PRACH resource to send PRACH when the UE does not support Msg2 PDSCH repetition and Msg4 PDSCH repetition.

[0051] In some embodiments, when the UE uses PRACH resources configured for PRACH repetition to repeatedly send PRACH, this can instruct the UE to support Msg2 PDSCH repetition and Msg4 PDSCH repetition.

[0052] Similarly, when the UE repeatedly sends Msg3 PUSCH or indicates support for Msg3 PUSCH repetition, this can instruct the UE to support Msg4 PDSCH repetition or the UE to request Msg4 PDSCH repetition.

[0053] In some embodiments, the UE request may include information related to the number of repetitions recommended by the UE for DL ​​transmission.

[0054] In another alternative, the UE can indicate support for Msg4 PDSCH repetition in the Media Access Control-Control Element (MAC-CE) within the Msg3 PUSCH. In this case, a Logical ID (LCID) can be defined to indicate that the MAC-CE is used to carry the indication of support for Msg4 PDSCH repetition.

[0055] Figure 2 A four-step random access (4-step RACH) procedure performed for initial access is illustrated according to some embodiments. The (4-step RACH) procedure 200 can be performed between UE 102 and gNB 210 for initial access. Figure 2A four-step RACH procedure is illustrated, which can support Msg2 PDSCH repetition and / or Msg4 PDSCH repetition to achieve coverage enhancement during initial access. In operation 202, UE 102 can use a PRACH resource to transmit a PRACH preamble configured to indicate support for Msg2 PDSCH and Msg4 PDSCH repetition. In operation 204, gNB 210 can indicate the number of Msg2 PDSCH repetitions in DCI format 1_0 with a CRC scrambled with RA-RNTI, and can transmit the Msg2 PDSCH using the indicated number of repetitions. In operation 206, the UE can transmit Msg3 PUSCH carrying L2 and L3 messages with or without repetition. In operation 208, gNB 210 can indicate the number of repetitions of Msg4 PDSCH in DCI format 1_0 with CRC scrambled with TC-RNTI, and can use the indicated number of repetitions to send Msg4PDSCH.

[0056] In some embodiments, a field for the number of repetitions for Msg2 PDSCH transmissions may be explicitly included in the downlink control information (DCI) used for scheduling Msg2 PDSCH. Specifically, the number of repetitions for Msg2 PDSCH transmissions may be included in DCI format 1_0, which has a cyclic redundancy check (CRC) scrambled with a random access radio network temporary identifier (RA-RNTI) used for the 4-step RACH procedure.

[0057] In these embodiments, after the UE sends Msg1 PRACH, the UE can begin monitoring the DCI in the control resource set (CORESET) / search space set during the random access response (RAR) window. The UE can attempt to decode the DCI within the RAR window.

[0058] In some embodiments, the set of repetitions for Msg2 PDSCH transmissions can be configured by higher layers using NR Residual Minimum System Information (RMSI), NR Other System Information (OSI), or dedicated Radio Resource Control (RRC) signaling. Furthermore, a field indicating the number of repetitions from the Msg2 PDSCH transmission set can be included in DCI format 1_0 with a CRC scrambled with RA-RNTI. If the set of repetitions has not been configured, a default set of repetitions for Msg2 PDSCH transmissions can be predefined. In some embodiments, after the UE successfully detects an SSB, it begins searching for system information such as RMSI (=SIB1), OSI (=SIBx), etc. After initial access, the UE can receive dedicated RRC signaling (typically UE-specific RRC configuration) from the gNB.

[0059] In some embodiments, the set of repetitions for Msg2 PDSCH transmission may include a repetition count as one (i.e., to indicate a single transmission of Msg2 PDSCH (a Msg2 PDSCH transmission without repetition)).

[0060] In some embodiments, when the number of repetitions configured for the Msg2 PDSCH transmission is one, the field in the DCI for the number of repetitions for the Msg2 PDSCH transmission may not exist. In this case, the number of repetitions for the Msg2 PDSCH transmission can be determined based on the configured number of repetitions. When more than one repetition is configured for the Msg2 PDSCH transmission, the field in the DCI for the number of repetitions for the Msg2 PDSCH transmission may exist. DCI format 1_0 is applicable to scheduling PDSCH and can therefore be used to indicate the number of repetitions for the Msg2 PDSCH transmission or the number of repetitions for the Msg4 PDSCH transmission.

[0061] The following text in Clause 7.3.1.2.1 of 3GPP TS 38.212 concerning PDSCH scheduling can be updated to include the repetition count as shown below. Since a portion of the reserved bits is used to indicate the repetition count, the reserved bits can also be updated (as shown below).

[0062] 7.3.1.2.1 Format 1_0 DCI format 1_0 is used to schedule PDSCH in a DL cell.

[0063] The following information is transmitted using DCI format 1_0 with CRC scrambled using C-RNTI, CS-RNTI, or MCS-C-RNTI: - Frequency domain resource allocation – bits - If CORESET 0 is configured for this cell, then This refers to the size of CORESET 0; if CORESET 0 is not configured for this cell, then... It is the size of the initial DL bandwidth portion.

[0064] - Time-domain resource allocation – 4 bits, defined in clause 5.1.2.1 of [6, TS38.214].

[0065] - VRB to PRB mapping – 1 bit, according to Table 7.3.1.2.2-5.

[0066] - Modulation and coding scheme – 5 bits, defined in Clause 5.1.3 of [6, TS38.214] using Table 5.1.3.1-1.

[0067] - TB scaling – 2 bits, defined in clause 5.1.3.2 of [6, TS38.214].

[0068] - SFN LSB – If msgB-responseWindow is configured to be greater than 10 ms, then it is 2 bits for DCI format 1_0 with CRC scrambled with MsgB-RNTI (as defined in Clause 8.2A of [5, TS 38.213]); or, if ra-ResponseWindow or ra-ResponseWindow-v1610 is configured to be greater than 10 ms, then it is 2 bits for DCI format 1_0 with CRC scrambled with RA-RNTI (as defined in Clause 8.2 of [5, TS 38.213]) and for operation in cells with shared spectrum channel access; otherwise, it is 0 bits.

[0069] - Number of repetitions – X bits - Reserved bits – (16–A–X) bits for operations in cells without shared spectrum access in frequency range 1 and frequency range 2-1; (18–A–X) bits for operations in cells with shared spectrum access in frequency range 1 or for operations in cells in frequency range 2-2, where the value of A is the number of bits used for the “LSB of SFN” field above.

[0070] In some embodiments, the number of repetitions used for scheduling Msg2 PDSCH can be implicitly determined in the DCI. In some embodiments, the X most significant bits (MSB) or least significant bits (LSB) of the Modulation and Coding Scheme (MCS) field in DCI format 1_0 with RA-RNTI scrambled CRC can be used to indicate the number of repetitions used for Msg2 PDSCH transmission. Additionally, the set of repetition counts can be configured by higher layers using RMSI, OSI, or RRC signaling. Furthermore, the X MSBs or LSBs of the MCS field in the DCI format with RA-RNTI scrambled CRC can be used to indicate the number of repetitions in the set of repetition counts for Msg2 PDSCH transmission. Furthermore, a set of MCS indices can be configured by higher layers using RMSI, OSI, or RRC signaling. For repeatedly transmitted Msg2 PDSCH transmissions, the MCS field is used to indicate one MCS in a set of MCS indices configured by the higher layer. In one example, the two MSBs of the MCS field in DCI format 1_0 with RA-TNTI scrambled CRC can be reused to indicate the number of repetitions of the Msg2 PDSCH transmission. Additionally, the remaining three LSBs of the MCS field can be used to indicate the MCS in an index of eight MCS values ​​configured by higher layers.

[0071] In some embodiments, the default PDSCH time-domain resource allocation (e.g., in Tables 5.1.2.1.1-2 and 5.1.2.1.1-3 in TS38.214) may include a parameter indicating the number of repetitions for Msg2 PDSCH transmission. In these embodiments, when the UE indicates support for Msg2 PDSCH repetition, the UE can use a new table to determine the time-domain resource allocation for Msg2 PDSCH transmission, which includes the number of repetitions for Msg2 PDSCH transmission as a parameter.

[0072] These embodiments can be applied to the transmission of MsgB PDSCH, which is scheduled by PDCCH (or DCI) format 1_0 for a 2-step RACH process, wherein the PDCCH format 1_0 has a CRC scrambled by MsgB-RNTI; however, the scope of the embodiments is not limited in this respect.

[0073] For initial access, implement coverage enhancement for Msg4 PDSCH. The following provides an example of coverage enhancement for initial access implementation of Msg4 PDSCH: In some embodiments, a field for the number of repetitions for Msg4 PDSCH transmissions may be included in the DCI format used for scheduling Msg4 PDSCH transmissions. Specifically, the number of repetitions for Msg4 PDSCH transmissions may be included in DCI format 1_0, which has a CRC scrambled with the Temporary Cell Radio Network Temporary Identifier (TC-RNTI) used for the 4-step RACH procedure. In these embodiments, the UE may begin monitoring the CORESET / search space to decode the DCI (used for Msg4 PDSCH scheduling) after transmitting Msg3.

[0074] In some embodiments, the set of repetitions for Msg4 PDSCH transmissions can be configured by higher layers using RMSI, OSI, or RRC signaling. Additionally, a field indicating the number of repetitions from the set of repetitions for Msg4 PDSCH transmissions can be included in DCI format 1_0, which has CRC scrambled with TC-RNTI. If the set of repetitions is not already configured, a default set of repetitions for Msg4 PDSCH transmissions can be predefined in the specification. As a further extension, the same set of repetitions for Msg2 PDSCH transmissions can be configured or predefined for Msg4 PDSCH transmissions. In some embodiments, the set of repetitions for Msg4 PDSCH transmissions can include repetitions that are counted as one.

[0075] In some embodiments, when the number of repetitions configured for the Msg4 PDSCH transmission is one, the field for the number of repetitions for the Msg4 PDSCH transmission in the DCI may not exist. In this case, the number of repetitions for the Msg4 PDSCH transmission is determined based on the configured number of repetitions. When more than one repetition is configured for the Msg2 PDSCH transmission, the field for the number of repetitions for the Msg4 PDSCH transmission in the DCI may exist. In some embodiments, the number of repetitions may be implicitly determined in the DCI used for scheduling the Msg4 PDSCH.

[0076] In some embodiments, the X most significant bits (MSBs) or least significant bits (LSBs) of the Modulation and Coding Scheme (MCS) field in DCI format 1_0 with RX-RNTI scrambled CRC can be used to indicate the number of repetitions for Msg3 PDSCH transmissions. Additionally, the set of repetition counts can be configured by higher layers using RMSI, OSI, or RRC signaling. Furthermore, the X MSBs or LSBs of the MCS field in DCI format with TC-RNTI scrambled CRC can be used to indicate the number of repetitions from the set of repetition counts for Msg4 PDSCH transmissions. Furthermore, a set of MCS indices can be configured by higher layers using RMSI, OSI, or RRC signaling. For repeatedly transmitted Msg2 PDSCH transmissions, the MCS field is used to indicate one MCS in a set of MCS indices configured by higher layers. In one example, the two MSBs of the MCS field in DCI format 1_0 with RA-TNTI scrambled CRC can be reused to indicate the number of repetitions for Msg2 PDSCH transmissions. Additionally, the remaining 3 LSBs of the MCS field can be used to indicate the MCS that comes from the 8 MCS indexes configured at the higher level.

[0077] In some embodiments, a parameter may be included in the default PDSCH time-domain resource allocation (e.g., in Tables 5.1.2.1.1-2 and 5.1.2.1.1-3 of TS38.214) to indicate the number of repetitions for Msg4 PDSCH transmissions. In this case, when the UE indicates support for Msg4 PDSCH repetitions, the UE can use a new table including a parameter with the number of repetitions for Msg4 PDSCH transmissions to determine the time-domain resource allocation for Msg4 PDSCH transmissions.

[0078] In some embodiments, an association (correspondence) can be defined between the number of repetitions of PRACH or Msg3 PUSCH transmissions and the number of repetitions of Msg4 PUSCH transmissions. In this case, the association can be explicitly configured by higher layers using RMSI, OSI, or RRC signaling, or it can be predefined in the specification.

[0079] In some embodiments, a one-to-one association can be defined between the number of repetitions for a PRACH or Msg3 PUSCH transmission and the number of repetitions for a Msg4 PUSCH transmission. Specifically, a first repetition for a PRACH or Msg3 PUSCH transmission is associated with a first repetition for a Msg4 PUSCH transmission, a second repetition for a PRACH or Msg3 PUSCH transmission is associated with a second repetition for a Msg4 PUSCH transmission, and so on. In this case, when the UE transmits a PRACH or Msg3 PUSCH with a first repetition, the gNB can use the associated repetition for the Msg4 transmission, and so on.

[0080] In some embodiments, a one-to-many association can be defined between the number of repetitions of a PRACH or Msg3 PUSCH transmission and the number of repetitions of a Msg4 PUSCH transmission. Specifically, a first repetition for a PRACH or Msg3 PUSCH transmission is associated with a first set of repetitions for a Msg4 PUSCH transmission, a second repetition for a PRACH or Msg3 PUSCH transmission is associated with a second set of repetitions for a Msg4 PUSCH transmission, and so on. In this case, a field in the DCI can be explicitly included or reused to indicate the number of repetitions of Msg4 PDSCH transmissions from the associated set of repetitions.

[0081] In some embodiments, for a PDSCH transmission scheduled by DCI format 1_0 with a CRC scrambled with C-RNTI, a field in DCI format 1_0 may be explicitly included or reused to indicate the number of repetitions of the PDSCH transmission.

[0082] In some embodiments, a parameter may be included in the time-domain resource allocation table for PDSCH transmission to indicate the number of repetitions of PDSCH transmissions scheduled by DCI format 1_0, wherein the CRC is scrambled by C-RNTI.

[0083] In some embodiments, the number of repetitions of PDSCH transmissions scheduled via DCI format 1_0 with a CRC scrambled by C-RNTI is associated with the number of repetitions of PDSCH transmissions scheduled via DCI format 1_0 with a CRC scrambled by TC-RNTI. In one example, the same number of repetitions for PDSCH transmissions scheduled via DCI format 1_0 with a CRC scrambled by TC-RNTI applies to the number of repetitions for PDSCH transmissions scheduled via DCI format 1_0 with a CRC scrambled by C-RNTI. In some embodiments, this may apply to the case prior to the UE receiving RRC configuration from the gNB. In one example, this may include PDSCH transmissions prior to RRC connection establishment.

[0084] Conditions for requesting Msg2 / Msg4 PDSCH repetition during random access The following provides an example of a condition for requesting the repetition of Msg2 / Msg4 PDSCH during random access: In some embodiments, the UE sends a request to repeat Msg2 PDSCH, MsgB PDSCH and / or Msg4 PDSCH only when certain conditions are met.

[0085] In some embodiments, if the RSRP (Reference Signal Received Power) measured at the UE is lower than the RSRP threshold, the UE sends a request to repeat Msg2 PDSCH, MsgB PDSCH, and / or Msg4 PDSCH. Furthermore, the RSRP threshold is configured by higher layers via RMSI, OSI, or RRC signaling. RSRP may correspond to the higher-layer filtered RSRP, L1-RSRP, and / or SS-RSRP.

[0086] In some embodiments, if the RSRQ (Reference Signal Received Quality) measured at the UE is below the RSRQ threshold, the UE sends a request to repeat Msg2 PDSCH, MsgB PDSCH, and / or Msg4 PDSCH. Furthermore, the RSRQ threshold is configured by higher layers via RMSI, OSI, or RRC signaling. The RSRQ may correspond to a higher-layer filtered RSRQ and / or SS-RSRQ.

[0087] Furthermore, if the SINR (signal-to-noise ratio) measured at the UE is lower than the SINR threshold, the UE can send repeated requests for Msg2PDSCH, MsgB PDSCH, and / or Msg4 PDSCH. Additionally, the SINR threshold can be configured by higher layers using RMSI, OSI, or RRC signaling. SINR can correspond to the higher-layer filtered SINR, L1-SINR, and / or SS-SINR.

[0088] Additionally, if the assumed PDSCH BLER (block error rate / block error rate) measured at the UE is higher than the BLER threshold, the UE can send requests for duplicate Msg2 PDSCH, MsgB PDSCH, and / or Msg4 PDSCH. Furthermore, the BLER threshold can be configured by higher layers using RMSI, OSI, or RRC signaling.

[0089] In some embodiments, a hypothetical BLER is calculated for a hypothetical PDSCH transmission with a hypothetical repetition count N, where N can be configured by higher layers using RMSI, OSI, or RRC signaling. Furthermore, multiple hypothetical BLER values ​​are calculated for different repetition counts, and the UE determines the recommended repetition count for the PDSCH transmission based on the largest hypothetical BLER value below a BLER threshold. Additionally, if the CQI measured at the UE is below a CQI threshold, the UE can send a request to repeat Msg2 PDSCH, MsgB PDSCH, and / or Msg4 PDSCH. Furthermore, the CQI threshold can be configured by higher layers using RMSI, OSI, or RRC signaling.

[0090] Figure 3 NTN-based NG RAN and terrestrial NG-RAN are illustrated according to some embodiments. For example... Figure 3 As shown, UE 102 can communicate with NTN-based NG RAN 302 via the NR-Uu interface. UE 102 can also communicate with terrestrial NGRAN 304 via the NR-Uu interface. The NTN-based NG RAN 302 can be at least one of a satellite and an upper-level platform station configured to provide communication between UE 102 and gNB 210. In these embodiments, the satellite and / or upper-level platform station acts as a repeater.

[0091] According to an embodiment, UE 102 can be configured to operate in a 5G New Radio (5G NR) network. To perform a four-step random access (4-step RACH) procedure for initial access, the UE can encode the Physical Uplink Shared Channel (PUSCH) transmission of Message 3 (Msg3) sent to the g Node B (gNB). The UE can also decode the Downlink Control Information (DCI) format used to schedule the Physical Downlink Shared Channel (PDSCH) transmission of Message 4 (Msg4). To achieve coverage enhancement during initial access, the UE can decode the retransmission of Msg4 PDSCH transmissions received from the gNB according to scheduling. In these embodiments, the retransmission of Msg4 PDSCH transmissions can be configured to the UE by means of higher-layer signaling and / or signaled to the UE by means of fields in the DCI format. In these embodiments, the retransmission of Msg4 PDSCH transmissions provides coverage enhancement during initial access.

[0092] In some embodiments, when the number of repetitions of Msg4 PDSCH is signaled to the UE via a field in the DCI format, the DCI format is DCI format 1_0 with cyclic redundancy check (CRC) bits scrambled with a Temporary Cell Radio Network Temporary Identifier (TC-RNTI). In these embodiments, when the number of repetitions of Msg4 PDSCH is configured via higher-layer signaling, the higher-layer signaling indicates a set of repetition counts, and the field in the DCI format indicates the number of repetitions of Msg4 PDSCH from that set of repetition counts.

[0093] In some embodiments, when the field indicating the number of repetitions of Msg4 PDSCH in the DCI format is absent, the processing circuitry is configured to decode non-repeating Msg4 PDSCH transmissions received from the gNB. In some other embodiments, the field indicating the number of repetitions of Msg4 PDSCH in the DCI format may indicate once, to indicate that the Msg4 PDSCH transmission received from the gNB has no repetitions.

[0094] In some embodiments, the UE can be configured to repeatedly transmit Msg3 PUSCH transmissions to indicate that the UE supports repeated transmission of Msg4 PDSCH transmissions.

[0095] In some embodiments, the UE can be configured to encode the Msg3PUSCH transmission using a Media Access Control-Control Element (MAC-CE), which instructs the UE to support the retransmission of the Msg4PDSCH transmission during the 4-step RACH process performed for initial access. In these embodiments, a Logical ID (LCID) can be used to indicate that the MAC-CE is used to carry an indication of supporting Msg4 PDSCH retransmission; however, the scope of the embodiments is not limited in this respect.

[0096] In some embodiments, the UE is configured to encode a UE capability information element (IE) sent to the gNB, the UE capability IE indicating that the UE supports repeated transmission of Msg4 PDSCH transmissions during the 4-step RACH process performed for initial access.

[0097] In some embodiments, the UE is configured to encode a request to repeatedly transmit Msg4 PDSCH transmissions to the gNB during a 4-step RACH process when the signal quality condition determined at the UE is below a threshold, wherein the request to repeatedly transmit Msg4 PDSCH transmissions is indicated in the Msg3 PUSCH transmission.

[0098] In some embodiments, as part of the 4-step RACH process, the processing circuitry is further configured to encode the Message 1 (Msg1) Physical Random Access Channel (PRACH) transmission sent to the gNB for initial access, the Msg1 PRACH transmission including one or more PRACH preambles transmitted at one or more PRACH timings (ROs), and to decode the Message 2 (Msg2) PDSCH Random Access Response (RAR) transmission received from the gNB, the Msg2 PDSCH including timing advance (TA) information. In these embodiments, the Msg1 PRACH transmission is configured to indicate whether the UE supports retransmission of at least one of the following: retransmission of the Msg2 PDSCH transmission during the 4-step RACH process performed for initial access; and retransmission of the Msg4 PDSCH transmission during the 4-step RACH process performed for initial access.

[0099] In some embodiments, to indicate that the UE does not support the repetition of Msg2 PDSCH, the processing circuitry configures the UE to transmit Msg1 PRACH transmissions using PRACH resources configured to the UE by means of higher-layer signaling. In these embodiments, to indicate that the UE supports the repetition of Msg2 PDSCH transmissions, the processing circuitry configures the UE to transmit Msg1 PRACH transmissions using a separate PRACH preamble for sharing PRACH timing (RO), or to transmit Msg1 PRACH transmissions using a separate RO different from the configured PRACH resources.

[0100] In some embodiments, using PRACH resources configured to the UE for PRACH repetition to send Msg1 PRACH transmissions may also instruct the UE to support repeated transmissions of Msg4 PDSCH transmissions; however, the scope of the embodiments is not limited in this respect.

[0101] In some embodiments, in order to transmit via a non-terrestrial network (NTN) (e.g., NTN-based NG RAN 302), Figure 3 The UE communicates with the gNB and receives DCI format and Msg4 PDSCH transmissions from the gNB via the NTN. In these embodiments, when the UE communicates with the gNB via the NTN, the Msg4 PDSCH transmission is repeatedly sent to achieve coverage enhancement. In these embodiments, when the UE communicates with the gNB via a terrestrial network (e.g., Figure 3 When the ground NG RAN 304 (shown) communicates with the gNB, the Msg4 PDSCH transmission is sent without repetition.

[0102] In some embodiments, the NTN includes at least one of a satellite and an upper-level platform station, both configured to provide communication between the UE and the gNB. In these embodiments, the satellite and the upper-level platform station may act as repeaters, transponders, or bends (transparent forwarding channels); however, since some functions of the gNB can be performed by either the satellite or the upper-level platform station, the scope of the embodiments is not limited in this respect.

[0103] Some embodiments involve a gNode B (gNB) configured to operate in a 5G New Radio (NR) network. To perform a four-step random access (4-step RACH) procedure for initial access using a User Equipment (UE), the gNB can decode the Physical Uplink Shared Channel (PUSCH) transmission of Message 3 (Msg3) from the UE and encode the Downlink Control Information (DCI) format for scheduling the Physical Downlink Shared Channel (PDSCH) transmission of Message 4 (Msg4). In these embodiments, the gNB can encode the retransmission of the Msg4 PDSCH transmission to the UE according to the schedule. In these embodiments, the retransmission of the Msg4 PDSCH transmission can be configured to the UE by means of higher-layer signaling and / or signaled to the UE by means of fields in the DCI format.

[0104] Figure 4 A functional block diagram of a wireless communication device according to some embodiments is shown. The wireless communication device 400 may be adapted to function as a UE or gNB configured to operate in a 5G NR or 6G network. Some embodiments relate to an apparatus for a UE or gNB including processing circuitry and memory configured to operate in a 5G NR or 6G network.

[0105] Wireless communication device 400 can also be used as a handheld device, mobile device, cellular phone, smartphone, tablet computer, netbook, wireless terminal, laptop computer, wearable computing device, femtocell, high data rate (HDR) user equipment, access point, access terminal or other personal communication system (PCS) device.

[0106] The wireless communication device 400 may include communication circuitry 402 and a transceiver 410, the transceiver 410 being used to transmit signals to and receive signals from other communication devices using one or more antennas 401. Communication circuitry 402 may include circuitry capable of operating physical layer (PHY) communication and / or media access control (MAC) communication to control access to a wireless medium, and / or operating any other communication layer for transmitting and receiving signals. The wireless communication device 400 may also include processing circuitry 406 and a memory 408 arranged to perform the operations described herein. In some embodiments, communication circuitry 402 and processing circuitry 406 may be configured to perform the operations detailed in the foregoing figures, schematic diagrams, and flowcharts.

[0107] According to some embodiments, communication circuitry 402 may be arranged to contend for the wireless medium and configure framing or packetization of communications over the wireless medium. Communication circuitry 402 may be arranged to transmit and receive signals. Communication circuitry 402 may also include circuitry for modulation / demodulation, up-conversion / down-conversion, filtering, amplification, etc. In some embodiments, processing circuitry 406 of wireless communication device 400 may include one or more processors. In other embodiments, two or more antennas 401 may be coupled to communication circuitry 402 arranged for transmitting and receiving signals. Memory 408 may store information used to configure processing circuitry 406 to perform operations for configuring and transmitting message frames and performing various operations described herein. Memory 408 may include any type of memory for storing information in a machine-readable (e.g., computer) form, including non-transitory memory. For example, memory 408 may include computer-readable storage devices, read-only memory (ROM), random access memory (RAM), disk storage media, optical storage media, flash memory devices, and other storage devices and media.

[0108] In some embodiments, the wireless communication device 400 may be part of a portable wireless communication device, which includes, for example, a personal digital assistant (PDA), a laptop or portable computer with wireless communication capabilities, a network tablet, a cordless phone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), a wearable computer device, or another device that can wirelessly receive and / or transmit information.

[0109] In some embodiments, the wireless communication device 400 may include one or more antennas 401. Antenna 401 may include one or more directional or omnidirectional antennas, such as dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmitting RF signals. In some embodiments, a single antenna with multiple apertures may be used instead of two or more antennas. In these embodiments, each aperture can be considered a separate antenna. In some multiple-input multiple-output (MIMO) embodiments, antennas can be effectively separated to achieve spatial diversity and different channel characteristics can be generated between each antenna and the antenna of the transmitting device.

[0110] In some embodiments, the wireless communication device 400 may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, a speaker, and other mobile device components. The display may be an LCD screen including a touchscreen.

[0111] Although the wireless communication device 400 is shown as having multiple individual functional elements, two or more of these functional elements can be combined and implemented by combinations of software-configurable elements (e.g., processing elements including digital signal processors (DSPs)) and / or other hardware elements. For example, some elements may include one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), radio frequency integrated circuits (RFICs), and combinations of various hardware and logic circuits for performing at least the functions described herein. In some embodiments, a functional element of the wireless communication device 400 may refer to one or more processes operating on one or more processing elements.

[0112] Embodiments can be implemented as one or a combination of hardware, firmware, and software. Embodiments can also be implemented as instructions stored on a computer-readable storage device that can be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device can include any non-transitory mechanism for storing information in a machine-readable (e.g., computer) form. For example, a computer-readable storage device can include read-only memory (ROM), random access memory (RAM), disk storage media, optical storage media, flash memory devices, and other storage devices and media. Some embodiments may include one or more processors and can be configured to have instructions stored on the computer-readable storage device. Some embodiments relate to a non-transitory computer-readable storage medium storing instructions for execution by processing circuitry of a user equipment (UE) configured to operate in a fifth-generation new radio (5G NR) network.

[0113] Example Example 1: A wireless communication system and method for a fifth-generation (5G) system or a new radio (NR) system: indicating, via the gNB, the number of repetitions for the Msg2 Physical Downlink Shared Channel (PDSCH) and the Msg4 PDSCH in a downlink control information (DCI) format; and transmitting the Msg2 PDSCH and the Msg4 PDSCH via the gNB according to the indicated number of repetitions.

[0114] Example 2: According to the method in Example 1, a set of Physical Random Access Channel (PRACH) resources is configured by the gNB, the set of PRACH resources being used to indicate support for Msg2 PDSCH repetition and Msg4 PDSCH repetition during random access, wherein the UE uses the configured PRACH resources to send a PRACH preamble to indicate support for Msg2 PDSCH repetition and Msg4 PDSCH repetition.

[0115] Example 3: According to the method described in Example 1, the DCI format is a DCI format 1_0 with cyclic redundancy check (CRC) scrambled with random access radio network temporary identifier (RA-RNTI), MsgB-RNTI and / or temporary cell-RNTI (TC-RNTI).

[0116] Example 4: According to the method described in Example 1, the UE may indicate support for repeating the Msg4 PDSCH in the Media Access Control-Control Element (MAC-CE) in the Msg3 PUSCH.

[0117] Example 5: According to the method described in Example 1, a field for the number of repetitions for the Msg2 PDSCH transmission may be explicitly included in the downlink control information (DCI) used to schedule the Msg2 PDSCH.

[0118] Example 6: According to the method described in Example 1, the set of repetitions for the Msg2PDSCH transmission can be configured by a higher layer using NR Residual Minimum System Information (RMSI), NR Other System Information (OSI), or Dedicated Radio Resource Control (RRC) signaling.

[0119] Example 7: According to the method described in Example 1, when the number of repetitions configured for the Msg2 PDSCH transmission is one, the field for the number of repetitions for the Msg2 PDSCH transmission in the DCI may not exist.

[0120] Example 8: According to the method of Example 1, X most significant bits (MSB) or least significant bits (LSB) of the modulation and coding scheme (MCS) field in DCI format 1_0 with CRC scrambled by RA-RNTI can be used to indicate the number of repetitions for the Msg2 PDSCH transmission.

[0121] Example 9: According to the method described in Example 1, a parameter may be included in the default PDSCH time-domain resource allocation A to indicate the number of repetitions for the Msg2 PDSCH transmission.

[0122] Example 10: According to the method of Example 1, a field for the number of repetitions for the Msg4 PDSCH transmission may be included in the DCI format used for scheduling Msg4 PDSCH transmissions.

[0123] Example 11: According to the method described in Example 1, the set of repetitions for the Msg4 PDSCH transmission can be configured by a higher layer using RMSI, OSI, or RRC signaling.

[0124] Example 12: According to the method described in Example 1, wherein when the number of repetitions configured for the Msg4 PDSCH transmission is one, the field for the number of repetitions for the Msg4 PDSCH transmission in the DCI may not exist.

[0125] Example 13: According to the method of Example 1, the X most significant bits (MSB) or least significant bits (LSB) of the modulation and coding scheme (MCS) field in DCI format 1_0 with CRC scrambled with RX-RNTI can be used to indicate the number of repetitions for Msg3 PDSCH transmission.

[0126] Example 14: According to the method described in Example 1, the correlation between the number of repetitions for PRACH or Msg3 PUSCH transmission and the number of repetitions for Msg4 PUSCH transmission can be defined.

[0127] Example 15: According to the method of Example 1, wherein for a PDSCH transmission scheduled by DCI format 1_0 with a CRC scrambled with C-RNTI, a field of DCI format 1_0 may be explicitly included or reused to indicate the number of repetitions of the PDSCH transmission.

[0128] Example 16: According to the method described in Example 1, the UE only sends a request to repeat Msg2 PDSCH, MsgB PDSCH and / or Msg4 PDSCH if certain conditions are met.

[0129] Example 17: According to the method of Example 1, if the RSRP (Reference Signal Received Power) measured at the UE is lower than the RSRP threshold, the UE sends a request to repeat Msg2 PDSCH, MsgB PDSCH and / or Msg4 PDSCH.

[0130] Example 18: According to the method of Example 1, if the RSRQ (Reference Signal Receive Quality) measured at the UE is lower than the RSRQ threshold, the UE sends a request to repeat Msg2 PDSCH, MsgB PDSCH and / or Msg4 PDSCH.

[0131] Example 19: According to the method described in Example 1, if the SINR (signal-to-noise ratio) measured at the UE is lower than the SINR threshold, the UE sends a request to repeat Msg2 PDSCH, MsgB PDSCH and / or Msg4 PDSCH.

[0132] Example 20: According to the method described in Example 1, if the hypothetical PDSCH BLER (block error rate / block error rate) measured at the UE is higher than the BLER threshold, the UE sends a request to repeat Msg2 PDSCH, MsgB PDSCH and / or Msg4PDSCH.

[0133] An abstract is provided to comply with 37 CFR. Section 1.72(b) requires an abstract that enables the reader to determine the nature and essence of the technical disclosure. Submitting an abstract can be understood as not being used to limit or interpret the scope or meaning of the claims. The appended claims are incorporated herein by reference, wherein each claim is itself an independent embodiment.

Claims

1. An apparatus for a user equipment (UE) configured to operate in a fifth-generation new radio (5G NR) network, the apparatus comprising: Processing circuitry; as well as memory, In order to perform a four-step random access (4-step RACH) procedure for initial access, the processing circuit is configured to perform the following operations: Encode the Physical Uplink Shared Channel (PUSCH) transmission of message 3 (Msg3) sent to node B (gNB); Decode the downlink control information (DCI) format used for the transmission of scheduling message 4 (Msg4) physical downlink shared channel (PDSCH); The repeated transmissions of the Msg4 PDSCH received from the gNB are decoded according to the schedule. The repeated transmission of the Msg4 PDSCH is performed in at least one of the following ways: The signaling is configured to the UE via higher-layer signaling; and The UE is informed by signaling using fields in the DCI format.

2. The apparatus of claim 1, wherein when the number of repetitions of Msg4PDSCH is signaled to the UE by means of the field in the DCI format, the DCI format is DCI format 1_0, the DCI format 1_0 having a cyclic redundancy check (CRC) scrambled with a temporary cell radio network temporary identifier (TC-RNTI), and When the repetition count of the Msg4 PDSCH is configured using the higher-layer signaling, the higher-layer signaling indicates a set of repetition counts, and the field in the DCI format indicates the repetition count of the Msg4 PDSCH from the set of repetition counts.

3. The apparatus of claim 2, wherein when the field in the DCI format indicating the number of repetitions of the Msg4 PDSCH is absent, the processing circuitry is configured to decode a non-repeating Msg4 PDSCH transmission received from the gNB.

4. The apparatus of claim 2, wherein the processing circuitry is configured to configure the UE to repeatedly transmit the Msg3 PUSCH transmission, thereby instructing the UE to support repeated transmission of the Msg4 PDSCH transmission.

5. The apparatus of claim 2, wherein the processing circuitry is configured to encode the Msg3 PUSCH transmission using a Media Access Control-Control Element (MAC-CE), the MAC-CE instructing the UE to support repeated transmission of the Msg4 PDSCH transmission during the 4-step RACH process performed for initial access.

6. The apparatus of claim 2, wherein the UE is configured to encode a UE capability information element (IE) sent to the gNB, the UE capability IE indicating that the UE supports repeated transmission of the Msg4 PDSCH transmission during the 4-step RACH process performed for initial access.

7. The apparatus of claim 2, wherein the UE is configured to encode a request to repeatedly transmit the Msg4 PDSCH transmission sent to the gNB during the 4-step RACH process when a signal quality condition determined at the UE is below a threshold, and to indicate the request to repeatedly transmit the Msg4 PDSCH transmission in the Msg3 PUSCH transmission.

8. The apparatus of claim 2, wherein, as part of the four-step RACH process, the processing circuitry is further configured to perform the following operations: The Physical Random Access Channel (PRACH) transmission of Message 1 (Msg1) sent to the gNB for initial access is encoded, the Msg1 PRACH transmission including one or more PRACH preambles transmitted in one or more PRACH timings (ROs); and The message 2 (Msg2) PDSCH random access response (RAR) transmission received from the gNB is decoded, wherein the Msg2 PDSCH includes timing advance (TA) information. The Msg1 PRACH transmission is configured to indicate whether the UE supports retransmission of at least one of the following: Repeated transmission of the Msg2 PDSCH transfer during the 4-step RACH process performed for initial access; and Repeated transmission of the Msg4 PDSCH transmission during the 4-step RACH process performed for initial access.

9. The apparatus of claim 8, wherein, in order to indicate that the UE does not support repeated transmission of the Msg2 PDSCH, the processing circuit configures the UE to use the PRACH resources configured for the UE to transmit the Msg1 PRACH transmission, and In order to instruct the UE to support repeated transmission of the Msg2 PDSCH, the processing circuit configures the UE to transmit the Msg1 PRACH transmission using a separate PRACH preamble for sharing the PRACH timing (RO) or to transmit the Msg1 PRACH transmission using a separate RO that is different from the configured PRACH resource.

10. The apparatus of claim 2, wherein, in order to communicate with the gNB via a non-terrestrial network (NTN), the DCI format and the Msg4 PDSCH transmission are received from the gNB via the NTN. When the UE communicates with the gNB via the NTN, the Msg4 PDSCH transmission is repeatedly sent to enhance coverage, and When the UE communicates with the gNB via the terrestrial network, the Msg4 PDSCH transmission is sent without duplication.

11. The apparatus of claim 10, wherein the NTN comprises at least one of a satellite and an upper-level platform station, the satellite and the upper-level platform station being configured to provide communication between the UE and the gNB.

12. A non-transitory computer-readable storage medium storing instructions for execution by processing circuitry of a user equipment (UE) configured to operate in a fifth-generation new radio (5G NR) network, wherein, in order to perform a four-step random access (4-step RACH) procedure for initial access, the processing circuitry is configured to perform the following operations: Encode the Physical Uplink Shared Channel (PUSCH) transmission of message 3 (Msg3) sent to node B (gNB); Decode the downlink control information (DCI) format used for the transmission of scheduling message 4 (Msg4) physical downlink shared channel (PDSCH); The repeated transmissions of the Msg4 PDSCH received from the gNB are decoded according to the schedule. The repeated transmission of the Msg4 PDSCH is performed in at least one of the following ways: The signaling is configured to the UE via higher-layer signaling; and The UE is informed by signaling using fields in the DCI format.

13. The non-transitory computer-readable storage medium of claim 12, wherein when the number of repetitions of the Msg4 PDSCH is signaled to the UE by means of the field in the DCI format, the DCI format is DCI format 1_0, the DCI format 1_0 having cyclic redundancy check (CRC) scrambled with a temporary cell radio network temporary identifier (TC-RNTI), and When the repetition count of the Msg4 PDSCH is configured using the higher-layer signaling, the higher-layer signaling indicates a set of repetition counts, and the field in the DCI format indicates the repetition count of the Msg4 PDSCH from the set of repetition counts.

14. The non-transitory computer-readable storage medium of claim 13, wherein the processing circuitry is configured to configure the UE to repeatedly transmit the Msg3 PUSCH transmission to indicate that the UE supports repeated transmission of the Msg4 PDSCH transmission.

15. The non-transitory computer-readable storage medium of claim 13, wherein the UE is configured to encode a request to repeatedly transmit the Msg4 PDSCH transmission sent to the gNB during the 4-step RACH process when a signal quality condition determined at the UE is below a threshold, and to indicate the request to repeatedly transmit the Msg4 PDSCH transmission in the Msg3 PUSCH transmission.

16. The non-transitory computer-readable storage medium of claim 13, wherein, as part of the four-step RACH process, the processing circuitry is further configured to perform the following operations: The Physical Random Access Channel (PRACH) transmission of Message 1 (Msg1) sent to the gNB for initial access is encoded, the Msg1 PRACH transmission including one or more PRACH preambles transmitted in one or more PRACH timings (ROs); and The message 2 (Msg2) PDSCH random access response (RAR) transmission received from the gNB is decoded, wherein the Msg2 PDSCH includes timing advance (TA) information. The Msg1 PRACH transmission is configured to indicate whether the UE supports retransmission of at least one of the following: Repeated transmission of the Msg2 PDSCH transfer during the 4-step RACH process performed for initial access; and Repeated transmission of the Msg4 PDSCH transmission during the 4-step RACH process performed for initial access.

17. The non-transitory computer-readable storage medium of claim 13, wherein, in order to communicate with the gNB via a non-terrestrial network (NTN), the DCI format and the Msg4 PDSCH transmission are received from the gNB via the NTN. When the UE communicates with the gNB via the NTN, the Msg4 PDSCH transmission is repeatedly sent to enhance coverage, and When the UE communicates with the gNB via the terrestrial network, the Msg4 PDSCH transmission is sent without duplication.

18. An apparatus for a g-Node B (gNB) configured to operate in a 5G New Radio (5G NR) network, the apparatus comprising: Processing circuitry; as well as memory, In order to utilize the User Equipment (UE) to perform a four-step random access (4-step RACH) procedure for initial access, the processing circuit is configured to perform the following operations: Decode the Physical Uplink Shared Channel (PUSCH) transmission of message 3 (Msg3) from the UE; The downlink control information (DCI) format used for the transmission of scheduling message 4 (Msg4) physical downlink shared channel (PDSCH) is encoded; The repeated transmission of the Msg4 PDSCH transmission sent to the UE is encoded according to the scheduling. The repeated transmission of the Msg4 PDSCH is performed in at least one of the following ways: The signaling is configured to the UE via higher-layer signaling; and The UE is informed to transmit by means of fields in the DCI format.

19. The apparatus of claim 18, wherein when the UE is signaled the number of repetitions of the Msg4 PDSCH by means of the field in the DCI format, the DCI format is DCI format 1_0, the DCI format 1_0 having a cyclic redundancy check (CRC) scrambled with a Temporary Cell Radio Network Temporary Identifier (TC-RNTI), and When the repetition count of the Msg4 PDSCH is configured using the higher-layer signaling, the higher-layer signaling indicates a set of repetition counts, and the field in the DCI format indicates the repetition count of the Msg4 PDSCH from the set of repetition counts.

20. The apparatus of claim 19, wherein when the UE communicates with the gNB via a non-terrestrial network (NTN), the Msg4 PDSCH transmission is repeatedly sent to achieve coverage enhancement, and When the UE communicates with the gNB via the terrestrial network, the Msg4 PDSCH transmission is sent without duplication.

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