WO2022031617A1

WO2022031617A1 - Dmrs indication in special slots for unpaired spectrum operations

Info

Publication number: WO2022031617A1
Application number: PCT/US2021/044222
Authority: WO
Inventors: Gregory ERMOLAEV; Sergey Sosnin; Gang Xiong; Jie Zhu
Original assignee: Intel Corporation
Priority date: 2020-08-06
Filing date: 2021-08-02
Publication date: 2022-02-10

Abstract

For unpaired spectrum operation, a user equipment (UE) configured for operation in a fifth-generation (5G) new radio (NR) network may be configured with a semi-static uplink/downlink (UL/DL) configuration comprising uplink slots, downlink slots and special slots. At least some of the special slots precede the uplink slots. The UE may determine PUSCH DM-RS positions within the uplink slots for transmission of a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH). The UE may decode configuration information received from a generation Node B (gNB) to indicate if additional DMRS are to be transmitted in the special slots that precede the uplink slots of the UL/DL configuration. The UE may transmit the additional DMRS at one or more symbol locations in the special slots if indicated by the configuration information, transmit the DMRS at the PUSCH DM-RS positions in the uplink slots, and transmit the PUSCH within the uplink slots.

Description

DMRS INDICATION IN SPECIAL SLOTS FOR UNPAIRED SPECTRUM

OPERATIONS

PRIORITY CLAIMS

[0001] This application claims the benefit of priority to United States Provisional Patent Application Serial No. 63/062,295, filed August 06, 2020 [reference number AD1647-Z], United States Provisional Patent Application Serial No. 63/083,568, filed September 25, 2020 [reference number AD2675-Z], and United States Provisional Patent Application Serial No. 63/185,816, filed May 07, 2021 [reference number AD6423-Z], each of which is incorporated herein by reference in its entirety,

TECHNICAL FIELD

[0002] Some embodiments relate to wireless networks including 3 GPP (Third Generation Partnership Project) and fifth-generation (5G) networks including 5G new radio (NR) (or 5G-NR) networks. Some embodiments pertain to use of demodulation reference signals (DMRS ) for uplink channels for unpaired spectrum operations. Some embodiments relate to cover enhancement for user equipment (UEs).

BACKGROUND

[0003] Mobile communications have evolved significantly from early voice systems to today’s highly sophisticated integrated communication platform. With the increase in different types of devices communicating with various network devices, usage of 3GPP 5G NR systems has increased. The penetration of mobile devices (user equipment or UEs) in modern society has continued to drive demand for a wide variety of networked devices in many disparate environments. 5G NR wireless systems are forthcoming and are expected to enable even greater speed, connectivity, and usability, and are expected to increase throughput, coverage, and robustness and reduce latency and operational and capital expenditures. 5G-NR networks will continue to evolve based on 3GPP LTE-Advanced with additional potential new radio access technologies (RATs) to enrich people’s lives with seamless wireless connectivity solutions delivering fast, rich content and services. As current cellular network frequency is saturated, higher frequencies, such as millimeter wave (mmWave) frequency, can be beneficial due to their high bandwidth.

[0004] One issue in 5G NR is need for improved communications with UEs that are further from a generation node B (gNB).

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] FIG. 1 A illustrates an architecture of a network, in accordance with some embodiments.

[0006] FIG. IB and FIG. 1C illustrate a non-roaming 5G system architecture in accordance with some embodiments.

[0007] FIG. 2A illustrates different DMRS patterns in different PUSCH repetitions, in accordance with some embodiments.

[0008] FIG. 2B illustrates Repeated DMRS patterns during PUSCH repetition: example 1, in accordance with some embodiments.

[0009] FIG. 2C illustrates Repeated DMRS pattern during PUSCH repetition: example 2, in accordance with some embodiments.

[0010] FIG. 2D illustrates DMRS pattern in case of cancellation: option

1, in accordance with some embodiments.

[0011] FIG. 2E illustrates DMRS pattern in case of cancellation: option

2, in accordance with some embodiments.

[0012] FIG. 2F illustrates DMRS pattern for even distribution of DMRS symbols across frequency hops, in accordance with some embodiments.

[0013] FIG. 2G illustrates Shared DMRS for inter-slot frequency hopping, in accordance with some embodiments.

[0014] FIG. 2H illustrates Shared DMRS for inter-repetition frequency hopping, in accordance with some embodiments.

[0015] FIG. 3A illustrates additional DMRS symbol in the special slot, in accordance with some embodiments. [0016] FIG. 3B illustrates double symbol DMRS located m the special slot, in accordance with some embodiments.

[0017] FIG. 3C illustrates Handling overlapping between additional DMRS symbols and SRS: Option 1, in accordance with some embodiments. [0018] FIG. 3D illustrates Handling overlapping between additional DMRS symbols and SRS: Option 2, in accordance with some embodiments. [0019] FIG. 3E illustrates Handling overlapping between additional DMRS symbols and PUCCH: Option 1, in accordance with some embodiments. [0020] FIG. 3F illustrates Handling overlapping between additional DMRS symbols and PUCCH: Option 2, in accordance with some embodiments. [0021] FIG. 3G illustrates Handling overlapping between additional DMRS symbols and PUCCH: Option 3, in accordance with some embodiments. [0022] FIG. 4 illustrates a functional block diagram of a wireless communication device, in accordance with some embodiments.

DETAILED DESCRIPTION

[0023] The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

[0024] Some embodiments are directed to a user equipment (UE) configured for operation in a fifth-generation (5G) new radio (NR) network. In these embodiments, for unpaired spectrum operation (i.e., time-division duplexing (TDD) operation), the UE may be configured with a semi-static uplink/downlink (UL/DL) configuration comprising a plurality of slots including uplink slots, downlink slots and special slots. In these embodiments, at least some of the special slots precede the uplink slots. In these embodiments, the UE may be configured to determine PUSCH DM-RS positions within the uplink slots for transmission of a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH). In these embodiments, the UE may be configured to decode configuration information received from a generation Node B (gNB) to indicate if additional DMRS are to be transmited in the special slots that precede the uplink slots of the UL/DL configuration. In these embodiments, the UE may transmit the additional DMRS at one or more symbol locations in the special slots if indicated by the configuration information, transmit the DMRS at the PUSCH DM-RS positions in the uplink slots, and transmit the PUSCH within the uplink slots. In these embodiments, the additional DMRS that are transmitted in the special slots may improve PUSCH coverage (e.g., for coverage enhancement or enhanced coverage) for a UE by providing improved channel estimation and decoding performance. This may be beneficial for MU- MIMO, although the scope of the embodiments is not limited in this respect. [0025] In some embodiments, the UE may also be configured to determine whether transmission of the additional DMRS at the symbol locations in the special slots conflict (i.e., overlap) with a uplink transmission. The UE may either refrain from transmission of the additional DMRS at the symbol locations in the special slots or refrain from transmission of a least a portion of the uplink transmission in response to determination of a conflict. In these embodiments, the determination as to whether or not to transmit the additional DMRS at the symbol locations in the special slots or transmit the scheduled uplink transmission may be based on several factors including a priority of the scheduled uplink transmission. These embodiments are discussed in more detail below.

[0026] In some embodiments, the symbol locations in the special slots for transmission of the additional DMRS may comprise a single last symbol of a special slot when single symbol DMRS is configured for transmission of the PUSCH. In some embodiments, the symbol locations in the special slots for transmission of the additional DMRS may comprise two last symbols of the special slot when double symbol DMRS is configured for transmission of the PUSCH.

[0027] In these embodiments, the UE is only configured to transmit the additional DMRS within a special slot that is immediately before the uplink slot for transmission of the PUSCH. In some embodiments, the UE may be configured to refrain from transmission of the additional DMRS at the symbol locations in the special slots unless the UE is configured for PUSCH repetition. [0028] In some embodiments, the UE may be configured to refrain from transmission of the additional DMRS at the symbol locations in the special slots unless the UE is configured for PUSCH repetition with a number of repetitions less than a configured value, (e.g., N==2, at least two or more PUSCH repetitions in the uplink slot that follows the special slot). In these embodiments, UE may only transmit the additional DMRS when the number of repetitions is larger than N and/or when PUSCH repetition is transmitted in the uplink slot right after the special slot. Note that N can be predefined or configured by higher lay ers via minimum system information (MSI), remaining minimum system information (RMSI), other system information (OSI) or dedicated radio resource control (RRC) signalling. In some embodiments, N, the number of repetitions, is at least 2, while in other embodiments, N is at least 3,

[0029] In some embodiments, when transmission of the additional DMRS at the symbol locations in the special slots conflict with a physical uplink control channel (PUCCH) carrying uplink control information (UCI), and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, the UE may be configured to drop the PUCCH (i.e., refrain from transmission of the PUCCH with the UCI), and multiplex the UCI on the PUSCH in the uplink slot. In these embodiments, the UE may be configured to transmit the additional DMRS at one or more symbol locations in the special slots. An example of these embodiments is illustrated in FIG. 3G described below⁷.

[0030] In some embodiments, when transmission of the additional DMRS at the symbol locations in the special slots conflict with a physical uplink control channel (PUCCH) carrying uplink control information (UCI) that include HARQ/ACK feedback, the UE may refrain from transmission of the additional DMRS at one or more symbol locations in the special slots and transmit the PUCCH carrying the UCI as scheduled. In these embodiments, the additional DMRS transmission is dropped and the HARQ/ACK feedback is transmitted since the HARQ/ACK feedback may be important and have a high priority. In these embodiments, the priority of the information in a scheduled UL transmission may be used to determine whether the additional DMRS is to be dropped. For example, a PUCCH carrying a UCI with high priority information may be transmitted and the additional DMRS may be dropped. On the other hand, a PUCCH carrying a UCI with low priority information may be dropped and the additional DMRS may be transmitted.

[0031] In some embodiments, the configuration information to indicate if the additional DMRS are to be transmitted in the special slots comprises dedicated radio-resource control (RRC) signalling. In these embodiments, the UE may decode the RRC signalling to determine the symbol locations of additional DMRS in the special slots.

[0032] In some embodiments, the configuration information to indicate if the additional DMRS are to be transmitted in the special slots is dynamically indicated in a DCI format. In some embodiments, one field in the DCI may be included in the DCI format 0_l and/or 0_2 to indicate whether additional DMRS symbol(s) are located in the special slot for the associated PUSCH transmission. In these embodiments, the DCI format triggers the transmission of the DMRS at the symbol locations in the special slots. In these embodiments, the DCI format indicate whether additional DMRS symbols are to be transmitted in a special slot and may indicate the locations in the special slots where the DMRS symbols are to be transmitted.

[0033] In some other embodiments, the configuration information to indicate if the additional DMRS are to be transmitted in the special slots may be configured by higher layers via minimum system information (MSI), remaining minimum system information (RMSI), other system information (OSI). In these embodiments, the indication may only apply for unpaired spectrum operation or when a semi-static TDD UL/DL configuration is configured.

[0034] In some embodiments, the configuration information to indicate if the additional DMRS are to be transmitted in the special slots comprises one or more additional bits in a reserved field of antenna port configuration information in a downlink control information (DCI) format. In these embodiments that use additional DMRS, more DMRS antenna ports can be used with double symbol DMRS for increased capacity with MLT-MIMO.

[0035] In some embodiments, the special slots have an uplink part comprising one or more symbol locations for transmission of uplink symbols and a downlink part, comprising two or more symbol locations for reception of downlink symbols. In these embodiments, the symbol locations for transmission of the additional DMRS are within the uplink part of the special slots. In these embodiments, when two symbol locations of a special slot comprise the uplink pail, one of these symbol locations may be configured for the additional DMRS transmission. When four symbol locations of a special slot comprise the uplink part, two of these symbol locations may be configured for the additional DMRS transmission, although the scope of the embodiments is not limited in this respect.

[0036] In some embodiments, the UE may be configured to use (e.g., follow) a DMRS configuration for the uplink slot for transmission of the additional DMRS in the special slot. In these embodiments, a same DMRS AP is used for the transmission of DMRS in special slot and in the uplink slot for the PUSCH transmission. The DMRS AP may be indicated by a field in the DCI for scheduling the PUSCH transmission or may be configured by higher layers for a configured grant (CG) CG-PUSCH transmission.

[0037] In some embodiments, the UE may determine the PUSCH DMRS positions within the uplink slots for transmission of the DMRS based on one or more of: a duration of the PUSCH (e.g., the scheduled data duration); additional positions for the DMRS configured by higher layer parameter “dmrs- AdditionalPosition”; whether mapping type A or type B is used for transmission of the PUSCH transmission, whether single symbol or double symbol DMRS is used for transmission of the PUSCH; and whether frequency hopping is employed for transmission of the PUSCH.

[0038] In some embodiments, the UE may be configured by a system information block 1 (SIB1) with the UL/DL configuration. In some embodiments, the UE may be configured by higher layer signalling such RRC signall ing, with the UL/DL configuration, although the scope of the embodiments is not limited in this respect.

[0039] Some embodiments are directed to a non- transitory computer- readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE) configured for operation in a fifthgeneration (5G) new radio (NR) network.

[0040] Some embodiments are directed to a generation Node B (gNB) configured for operation in a fifth-generation (5G) new radio (NR) network. In these embodiments, for unpaired spectrum operation (i.e., TDD operation), the gNB may configure a user equipment (UE) with a semi-static uplink/downlink (UL/DL) configuration comprising a plurality of slots including uplink slots, downlink slots and special slots. In these embodiments, at least some of the special slots precede the uplink slots. In these embodiments, the gNB may determine PUSCH DM-RS positions within the uplink slots for reception of a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH). In these embodiments, the gNB may also encode configuration information for transmission to a UE to indicate if additional DMRS are to be transmitted by the UE in the special slots that precede the uplink slots of the UL/DL configuration. In these embodiments, the gNB may also decode the additional DMRS, received from the UE, at one or more symbol locations in the special slots if indicated by the configuration information. In these embodiments, the gNB may also decode the DMRS, received from the UE, at the PUSCH DM- RS positions in the uplink slots. In these embodiments, the gNB may also decode the PUSCH, received from the UE, within the uplink slots based on the additional DMRS received from the UE in the special slots and the DMRS received from the UE at the PUSCH DM-RS positions in the uplink slots.

[0041] In some of these embodiments, the configuration information to indicate if the additional DMRS are to be transmitted in the special slots comprises one or more additional bits in antenna port configuration information in a downlink control information (DCI) format provided by the gNB.

[0042] These embodiments are described in more detail below.

[0043] FIG. 1 A illustrates an architecture of a network in accordance with some embodiments. The network 140A is shown to include user equipment (UE) 101 and UE 102. The UEs 101 and 102 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks) but may also include any mobile or non-mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, drones, or any other computing device including a wired and/or wireless communications interface. The UEs 101 and 102 can be collectively referred to herein as UE 101, and UE 101 can be used to perform one or more of the techniques disclosed herein. [0044] Any of the radio links described herein (e.g., as used m the network 140A or any other illustrated network) may operate according to any exemplary radio communication technology and/or standard.

[0045] LTE and LTE- Advanced are standards for wireless communications of high-speed data for UE such as mobile telephones. In LTE- Advanced and various wireless systems, carrier aggregation is a technology according to which multiple carrier signals operating on different frequencies may be used to cany communications for a single UE, thus increasing the bandwidth available to a single device. In some embodiments, carrier aggregation may be used where one or more component carriers operate on unlicensed frequencies.

[0046] Embodiments described herein can be used in the context of any spectrum management scheme including, for example, dedicated licensed spectrum, unlicensed spectrum, (licensed) shared spectrum (such as Licensed Shared Access (LSA) in 2.3-2.4 GHz, 3.4-3.6 GHz, 3.6-3.8 GHz, and further frequencies and Spectrum Access System (SAS) in 3.55-3.7 GHz and further frequencies).

[0047] Embodiments described herein can also be applied to different Single Carrier or OFDM flavors (CP-OFDM, SC-FDMA, SC-OFDM, filter bank-based multicarrier (FBMC), OFDMA, etc.) and in particular 3GPP NR (New Radio) by allocating the OFDM carrier data bit vectors to the corresponding symbol resources.

[0048] In some embodiments, any of the UEs 101 and 102 can comprise an In ternet-of- Things (loT) UE or a Cellular loT (CIoT) UE, which can comprise a network access layer designed for low-power loT applications utilizing short-lived UE connections. In some embodiments, any of the UEs 101 and 102 can include a narrowband (NB) loT UE (e.g., such as an enhanced NB- loT (eNB-IoT) UE and Further Enhanced (FeNB-IoT) UE). An loT UE can utilize technologies such as machine-to-machine (M2M) or machine-type communications (MTC) for exchanging 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 loT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An loT network includes interconnecting loT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The loT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the loT network.

[0049] In some embodiments, any of the UEs 101 and 102 can include enhanced MTC (eMTC) UEs or further enhanced MTC (FeMTC) UEs.

[0050] The UEs 101 and 102 may be configured to connect, e.g,, communicatively couple, with a radio access network (RAN) 110. The RAN 110 may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), a NextGen RAN (NG RAN), or some other type of RAN. The UEs 101 and 102 utilize connections 103 and 104, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 103 and 104 are illustrated as an air interface to enable communicative coupling and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to- Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3GPP Long Term Evolution (LTE) protocol, a fifth-generation (5G) protocol, a New Radio (NR.) protocol, and the like.

[0051] In an aspect, the UEs 101 and 102 may further directly exchange communication data via a ProSe interface 105. The ProSe interface 105 may alternatively be referred to as a sidelink interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a Physical Sidelink Broadcast Channel (PSBCH).

[0052] The UE 102 is shown to be configured to access an access point (AP) 106 via connection 107. The connection 107 can comprise a local wireless connection, such as, for example, a connection consistent with any IEEE 802. 11 protocol, according to which the AP 106 can comprise a wireless fidelity (WiFi®) router. In this example, the AP 106 is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below).

[0053] The RAN 110 can include one or more access nodes that enable the connections 103 and 104. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), Next Generation NodeBs (gNBs), RAN nodes, and the like, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). In some embodiments, the communication nodes 111 and 112 can be transmi ssion/recepti on points (TRPs). In instances when the communication nodes 11 1 and 112 are NodeBs (e.g., eNBs or gNBs), one or more TRPs can function within the communication cell of the NodeBs. The RAN 110 may include one or more RAN nodes for providing macrocells, e.g., macro RAN node 111, and one or more RAN nodes for providing femtocells or picocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node 112.

[0054] Any of the RAN nodes 111 and 112 can terminate the air interface protocol and can be the first point of contact for the UEs 101 and 102. In some embodiments, any of the RAN nodes 111 and 112 can fulfill various logical functions for the RAN 110 including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. In an example, any of the nodes 111 and/or 112 can be a new generation Node-B (gNB), an evolved node-B (eNB), or another type of RAN node.

[0055] The RAN 1 10 i s shown to be communicatively coupled to a core network (CN) 120 via an S I interface 113. In embodiments, the CN 120 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN (e.g., as illustrated in reference to FIGS. 1B-1C). In this aspect, the SI interface 113 is split into two parts: the Sl-U interface 114, which carries traffic data between the RAN nodes 1 1 1 and 112 and the serving gateway (S-GW) 122, and the SI -mobility management entity (MME) interface 115, which i s a signaling interface between the RAN nodes 111 and 112 and MMEs 121.

[0056] In this aspect, the CN 120 comprises the MMEs 121, the S-GW 122, the Packet Data Network (PDN) Gateway (P-GW) 123, and a home subscriber server (HSS) 124. The MMEs 121 may be similar in function to the control plane of legacy Serving General Packet Radio Service (GPRS) Support Nodes (SGSN). The MMEs 121 may manage mobility embodiments in access such as gateway selection and tracking area list management. The HSS 124 may comprise a database for network users, including subscription-related information to support the network entities' handling of communication sessions. The CN 120 may comprise one or several HSSs 124, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 124 can provide support for routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc.

[0057] The S-GW 122 may terminate the S I interface 113 towards the RAN 110, and routes data packets between the RAN 110 and the CN 120. In addition, the S-GW 122 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3 GPP mobility. Other responsibilities of the S-GW 122 may include a lawful intercept, charging, and some policy enforcement.

[0058] The P-GW 123 may terminate an SGI interface toward a PDN. The P-GW 123 may route data packets between the EPC network 120 and external networks such as a network including the application server 184 (alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 125. The P-GW 123 can also communicate data to other external networks 131 A, which can include the Internet, IP multimedia subsystem (IPS) network, and other networks. Generally, the application server 184 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this aspect, the P-GW 123 is shown to be communicatively coupled to an application server 184 via an IP interface 125. The application server 184 can also be configured to support one or more communication sendees (e.g., Voice-over- Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UEs 101 and 102 via the CN 120.

[0059] The P-GW 123 may further be a node for policy enforcement and charging data collection. Policy and Charging Rules Function (PCRF) 126 is the policy and charging control element of the CN 120. In a non-roaming scenario, in some embodiments, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with a local breakout of traffic, there may be two PCRFs associated with a UE’s IP- CAN session: a Home PCRF (H-PCRF) within an HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 126 may be communicatively coupled to the application server 184 via the P- GW 123.

[0060] In some embodiments, the communication network 140A can be an loT network or a 5G network, including 5G new radio network using communications in the licensed (5G NR) and the unlicensed (5G NR-U) spectrum. One of the current enablers of loT is the narrowband-IoT (NB~IoT). [0061] An NG system architecture can include the RAN 1 10 and a 5G network core (5GC) 120. The NG-RAN 110 can include a plurality of nodes, such as gNBs and NG-eNBs. The core network 120 (e.g., a 5G core network or 5GC) can include an access and mobility function (AMF) and/or a user plane function (UPF). The AMF and the UPF can be communicatively coupled to the gNBs and the NG-eNBs via NG interfaces. More specifically, in some embodiments, the gNBs and the NG-eNBs can be connected to the AMF by NG- C interfaces, and to the UPF by NG-U interfaces. The gNBs and the NG-eNBs can be coupled to each other via Xn interfaces.

[0062] In some embodiments, the NG system architecture can use reference points between various nodes as provided by 3GPP Technical Specification (TS) 23.501 (e.g., VI 5.4.0, 2018-12). In some embodiments, each of the gNBs and the NG-eNBs can be implemented as a base station, a mobile edge server, a small cell, a home eNB, and so forth. In some embodiments, a gNB can be a master node (MN) and NG-eNB can be a secondary node (SN) in a 5G architecture. [0063] FIG. IB illustrates a non-roaming 5G system architecture m accordance with some embodiments. Referring to FIG. IB, there is illustrated a 5G system architecture 140B in a reference point representation. More specifically, UE 102 can be in communication with RAN 110 as well as one or more other 5G core (5GC) network entities. The 5G system architecture 140B includes a plurality of 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. The UPF 134 can provide a connection to a data network (DN) 152, which can include, for example, operator services, Internet access, or third-party services. The AMF 132 can be used to manage access control and mobility and can also include network slice selection functionality. The SMF 136 can be configured to set up and manage various sessions according to network policy. The UPF 134 can be deployed in one or more configurations according to the desired service type. The PCF 148 can be configured to provide a policy framework using network slicing, mobility management, and roaming (similar to PCRF in a 4G communication system). The UDM can be configured to store subscriber profiles and data (similar to an HSS in a 4G communication system).

[0064] In some embodiments, the 5G system architecture 140B includes an IP multimedia subsystem (IMS) 168B as well as a plurality of IP multimedia core network subsystem entities, such as call session control functions (CSCFs). More specifically, the IMS 168B includes a CSCF, which can act as a proxy CSCF (P-CSCF) 162BE, a serving CSCF (S-CSCF) 164B, an emergency CSCF (E-CSCF) (not illustrated in FIG. IB), or interrogating CSCF (I-CSCF) 166B. The P-CSCF 162B can be configured to be the first contact point for the UE 102 within the IM subsystem (IMS) 168B. The S-CSCF 164B can be configured to handle the session states in the network, and the E-CSCF can be configured to handle certain embodiments of emergency sessions such as routing an emergency request to the correct emergency center or PSAP. The I-CSCF 166B can be configured to function as the contact point within an operator's network for all IMS connections destined to a subscriber of that network operator, or a roaming subscriber currently located within that network operator's service area. In some embodiments, the I-CSCF 166B can be connected to another IP multimedia network 170E, e.g., an IMS operated by a different network operator.

[0065] In some embodiments, the UDM/HSS 146 can be coupled to an application server 160E, which can include a telephony application server (TAS) or another application server (AS). The AS 160B can be coupled to the IMS 168B via the S-CSCF 164B or the I-CSCF 166B.

[0066] A reference point representation shows that interaction can exist between corresponding NF services. For example, FIG. IB illustrates the following reference points: N1 (between the UE 102 and the AMF 132), N2 (between the RAN 110 and the AMF 132), N3 (between the RAN 110 and the UPF 134), N4 (between the SME 136 and the UPF 134), N5 (between the PCF 148 and the AF 150, not shown), N6 (between the UPF 134 and the DN 152), N7 (between the SMF 136 and the PCF 148, not shown), N8 (between the UDM 146 and the AMF 132, not shown), N9 (between two UPFs 134, not shown), N10 (between the UDM 146 and the SMF 136, not shown), N1 1 (between the AMF 132 and the SMF 136, not shown), N12 (between the AUSF 144 and the AMF 132, not shown), N13 (between the AUSF 144 and the UDM 146, not shown), N14 (between two AMFs 132, not shown), N15 (between the PCF 148 and the AMF 132 in case of a non-roaming scenario, or between the PCF 148 and a visited network and AMF 132 in case of a roaming scenario, not shown), N16 (between two SMFs, not shown), and N22 (between AMF 132 and NSSF 142, not shown). Other reference point representations not shown in FIG. IB can also be used.

[0067] FIG. 1C illustrates a 5G system architecture 140C and a sendeebased representation. In addition to the network entities illustrated in FIG. IB, system architecture 140C can also include a network exposure function (NEF) 154 and a network repository function (NRF) 156. In some embodiments, 5G system architectures can be service-based and interaction between network functions can be represented by corresponding point-to-point reference points Ni or as service-based interfaces. [0068] In some embodiments, as illustrated m FIG. 1C, service-based representations can be used to represent network functions within the control plane that enable other authorized network functions to access their services. In this regard, 5G system architecture 140C can include the following service-based interfaces: Namf 158H (a service-based interface exhibited by the AMF 132), Nsmf 1581 (a sendee-based interface exhibited by the SMF 136), Nnef 158B (a service-based interface exhibited by the NEF 154), Npcf 158D (a service-based interface exhibited by the PCF 148), a Nudm 158E (a service-based interface exhibited by the UDM 146), Naf 158F (a service-based interface exhibited by the AF 150), Nnrf 158C (a service-based interface exhibited by the NRF 156), Nnssf 158A (a service-based interface exhibited by the NSSF 142), Nausf 158G (a service-based interface exhibited by the AUSF 144). Other service-based interfaces (e.g., Nudr, N5g-eir, and Nudsf) not shown in FIG. 1C can also be used.

[0069] In some embodiments, any of the UEs or base stations described in connection with FIGS. 1 A-1C can be configured to perform the functionalities described herein.

[0070] Mobile communication has evolved significantly from early voice systems to today's highly sophisticated integrated communication platform. The next generation wireless communication system, 5G, or new radio (NR) will provide access to information and sharing of data anywhere, anytime by various users and applications. NR is expected to be a unified network/ system that target to meet vastly different and sometime conflicting performance dimensions and sendees. Such diverse multi-dimensional requirements are driven by different services and applications. In general, NR will evolve based on 3 GPP LTE- Advanced with additional potential new Radio Access Technologies (RATs) to enrich people lives with better, simple and seamless wireless connectivity solutions. NR will enable everything connected by wireless and deliver fast, rich contents and services.

[0071] For cellular system, coverage is an important factor for successful operation. Compared to LTE, NR can be deployed at relatively higher carrier frequency in frequency range 1 (FR1), e.g., at 3.5GHz. In this case, coverage loss is expected due to larger path-loss, which makes it more challenging to maintain an adequate quality of service. Typically, uplink coverage is the bottleneck for system operation considering the low transmit power at UE side. [0072] For NR, dynamic grant and configured grant based physical uplink shared channel (PUSCH) transmission are supported. For dynamic grant PUSCH transmission, PUSCH is scheduled by downlink control information (DCO) format 0 _0 , 0_1 or 0_2. Further, two types of configured grant PUSCH transmission are specified. In particular, for Type 1 configured grant PUSCH transmission, UL data transmission is only based on radio resource control (RRC) (re)configuration without any layer 1 (LI) signalling. In particular, semistatic resource may be configured for one UE, which includes time and frequency resource, modulation and coding scheme, reference signal, etc. For Type 2 configured grant PUSCH transmission, UL. data transmission is based on both RRC configuration and LI signaling to activate/ deactivate UL data transmission.

[0073] In NR Rel-15, PUSCH transmissions include configured number of demodulation reference signal (DMRS) symbols that can be used to provide a predictable quality of channel estimation. As defined in TS38.211 , up to four DMRS symbols can be used. More specifically:

[0074] If intra-slot frequency hopping is disabled, up to four DMRS symbols are configured for the whole PUSCH transmission, and

[0075] If intra-slot frequency hopping is enabled, up to two DMRS symbols are configured for each hop of PUSCH transmission

[0076] Further, in NR Rel-15, a number of repetiti ons can be configured for the transmission of PUSCH to help improve the coverage performance. When repetition is employed for the transmi ssion of PUCCH and PUSCH, same time domain resource allocation (TDRA) is used in each slot. In addition, interslot frequency hopping can be configured to improve the performance by exploiting frequency diversity. In Rel-16, the number of repetitions for PUSCH can be dynamically indicated in the DCI.

[0077] As mentioned above, DMRS overhead and number of DMRS symbols for PUSCH are configured by higher layers via RRC signalling and is fixed during certain period of time. When repetition is applied for PUSCH transmission, and when UE is in stationary condition such that the channel condition does not change much, DMRS may not be needed or the number of DMRS symbols may be reduced m some of slots during repetition. In this case, the unused DMRS symbols can be allocated for PUSCH transmission, thereby reducing code rate and improving decoding performance. Hence, certain mechanisms may need to be defined to dynamically indicate the DMRS patterns for PUSCH transmission.

[0078] This disclosure includes embodiments of mechanisms for dynamic indication of DMRS patterns for PUSCH transmission with repetition.

[0079] Improve coverage of NR PU SCH

[0080] Dynamic indication of DMRS patterns for PUSCH transmission with repetition

[0081] As mentioned above, when repetition is applied for PUSCH transmission, and when UE is in stationary' condition such that the channel condition does not change much, DMRS may not be needed or the number of DMRS symbols may be reduced in some of slots during repetition. In this case, the unused DMRS symbols can be allocated for PUSCH transmission, thereby reducing code rate and improving decoding performance. Hence, certain mechanisms may need to be defined to dynamically indicate the DMRS patterns for PUSCH transmission.

[0082] Note that DMRS-less operation may be applied for different scenarios as follows:

[0083] PUSCH repetition type A where static channel spans across several slots.

[0084] PUSCH repetition type B where channel for subsequent repetitions may be inferred from the channel estimate for first repetition.

[0085] Embodiments of dynamic indication of DMRS patterns for PUSCH transmission with repetition are provided as follows:

[0086] In one embodiment set, different DMRS patterns or configurations including PUSCH mapping type, DMRS type 1 or 2 the number of DMRS symbols and positions of DMRS symbols may be used in one or more repetitions for PUSCH transmission. In particular, a first DMRS configuration or pattern including number of DMRS symbols and DMRS position is configured in a first. PUSCH repetition or transmission occasion or slot, while a second DMRS configuration or pattern is configured in a second PUSCH repetition or transmission occasion or slot, [0087] In one option, the first DMRS configuration or pattern in the first PUSCH repetition or transmission occasion or slot may include a greater number of DMRS symbols than the second DMRS configuration or pattern in the second PUSCH repetition or transmission occasion or slot. In this case, DMRS symbols from multiple PUSCH repetitions or transmission occasions or slots may be jointly employed for channel estimation. This cross-slot channel estimation may help in improving channel estimation performance, and thereby improving decoding performance, especially when relatively large repetition level is used for PUSCH repetition.

[0088] In another option, the second DMRS configuration or pattern may not include DMRS symbols in the second PUSCH repetition or transmission occasion or slot. In this case, estimated channel from the first PUSCH repetition or transmission occasion or slot can be used for the second PUSCH repetition or transmission occasion or slot.

[0089] In one example, for PUSCH repetition type A, four DMRS symbols can be configured in the first slot while DMRS symbol is not present in the second slot. FIG . 2A illustrates this example of different DMRS patterns in different PUSCH repetitions.

[0090] In another embodiment set, a set of DMRS configurations or patterns over one or more PUSCH repetitions or slots can be predefined in the specification or configured by higher layers via minimum system information (MSI), remaining minimum system information (RMSI), other system information (OSI) or dedicated radio resource control (RRC) signalling or dynamically indicated in medium access control --- control element (MAC-CE) or a downlink control information (DCI) or a combination thereof.

[0091] In one option, for PUSCH scheduled by a DCI format 0_l and/or 0 2, a set of DMRS configurations or patterns over one or more PUSCH repetitions or slots can be configured by dedicated RRC signalling. Further, one field in the DCI format 0 1 and/or 0 2 can be used to indicate one DMRS configuration or pattern over one or more PUSCH repetitions or slots from the set of configured DMRS configurations or patterns.

[0092] Note that this option may apply for the case when no repetition is applied for PUSCH transmission. In particular, a set of DMRS configurations for one PUSCH transmission can be configured by higher layers via RRC signalling. Further, one field m the DCI format 0 1 and/or 0 2 is used to indicate one DMRS configuration from the set of DMRS configurations for PUSCH transmission. Similar to above, this DMRS configuration may include additional DMRS positions.

[0093] In another option, for configured grant PUSCH, a DMRS configuration or pattern over one or more PUSCH repetitions or slots can be configured by higher layers via dedicated RRC signalling when PUSCH repetition is configured.

[0094] Yet in another option, for PUSCH scheduled by fallback DCI or DCI format 0 0 or random-access response (RAR) uplink grant or fallback RAR uplink grant, DMRS configuration or pattern over one slot or transmission occasion is used.

[0095] In another embodiment set, dmrs-AdditionalPosition parameter in DMRS-UplmkConfig can be extended to indicate more than one additional DMRS positions which correspond to PUSCH in different repetitions or transmission occasions or slots. Note that for this option, first DMRS symbol in each PUSCH repetition or transmission occasion or slot, if present, can be in the same position. Further, same PUSCH mapping type and DMRS type, (e.g., whether DMRS type I or 2 is used) can be used in each PUSCH repetition or transmission occasion or slot.

[0096] In one example, dmrs-AdditicmalPctsition {post , posO, pos 0, posO} can be used to indicate that the additional DMRS position with pos 1 is used for DMRS in the first PUSCH repetition and the additional DMRS positions with posO is used for DMRS in the second to fourth PUSCH repetition. [0097] In another embodiment set, a new RRC parameter or existing parameter dmrs-AdditionalPosition can be used to indicate one row from a configured or predefined table for a set of DMRS configurations or patterns.

Note that this may help reduce signalling overhead.

[0098] Table 1 illustrates one example of a set of additional DMRS positions in different PUSCH slots. In the example, one row in the table is used to indicate one or more additional DMRS positions in different PUSCH repetitions or transmission occasions or slots. Note that the first four rows provide behavior similar to Rel- 15 with same number of DMRS symbols configured for each PUSCH repetition. [0099]

[00100] Table 1. A set of additional DMRS positions in different PUSCH slots: Example 1

[00101] Table 2 illustrates one example of a set of additional DMRS positions in different PUSCH slots. In the example, one row in the table is used to indicate one or more additional DMRS positions in different PUSCH repetitions or transmission occasions or slots. Note that in the table, “none” indicates that DMRS symbol is not present in the corresponding PUSCH repetition or transmission occasion or slot.

[00102] Table 2. A set of additional DMRS positions in different PUSCH slots: Example 2

[00103] In another option, multiple set of additional DMRS positions may be configured by RRC signalling based on the indicated row from a table as mentioned above. Further, one field in the DCI can be used to indicate a set of additional DMRS positions from the multiple set of additional DMRS positions for PUSCH repetitions, transmission occasions, or slots.

[00104] In one example, multiple set of additional DMRS positions can be configured as {0, 1, 4, 5} from Table 2. Further, one field in the DCI can be used to indicate row {4} or additional DMRS positions {posl, post)} for PUSCH repetitions, transmission occasions, or slots.

[00105] In another embodiment set, when the number of repetitions for PUSCH transmission is larger than the size of the set of configured DMRS patterns, the set of configurated DMRS patterns repeats across the PUSCH repetition. [00106] In one option, assuming the size of set of configured DMR S patterns as N, and the number of repetitions for PUSCH transmission as M, the DMRS pattern index used from the set of configured DMRS patterns can be given as

[00107]

[00108] Where is the DMRS pattern index and is the

PUSCH repetition index.

[00109] FIG. 2B illustrates one example of repeated DMRS patterns during PUSCH repetition. In the example, {pos3, none} are configured for a set of additional DMRS positions. When the number of repetitions is 4, based on the repeated DMRS patterns, 4 DMRS symbols are allocated within the slot #0 and #2 and DMRS symbols are not present in the slot #1 and #3.

[00110] In another option, the DMRS pattern may be repeated within one frequency hop when enhanced frequency hopping is applied for PUSCH repetition, where N contiguous PUSCH repetitions use a first same frequency resource before they switch to a second frequency resource. As a further extension, the size of set of DMRS patterns may be aligned with N for enhanced frequency hopping pattern.

[00111] FIG. 2C illustrates one example of repeated DMRS patterns during PUSCH repetition. In the example, {pos3, post } are configured for a set of additional DMRS positions. Further, enhanced frequency hopping pattern is used, where PUSCH transmission occupies the same frequency resource for two slots before it switches to another frequency resource. Based on this option, 4 DMRS symbols are allocated within the slot #0 and #2 and 2 DMRS symbols are allocated in the slot #1 and #3.

[00112] In another embodiment set, in case when a repetition or transmission occasion of the PUSCH transmission is cancelled during the repetition, e.g., due to overlapping of other physical channels or semi-static TDD DL/UL configuration, the repeated DMRS pattern is continued regardless of whether one PUSCH repetition or transmission occasion is dropped.

[00113] FIG. 2D illustrates one example of repeated DMRS pattern in case of cancellation of PUSCH transmission with repetition. In the example, PUSCH transmission in the slot# 1 is dropped. Based on this option, UE will follow' the repeated DMRS pattern without considering the cancellation of PUSCH transmission. In this case, 4 DMRS symbols are allocated within the slot #0 and #2 and DMRS symbols are not present in the slot #3.

[00114] Yet in another option, when a PUSCH repetition or transmission occasion is cancelled during the repetition, the repeated DMRS pattern is resumed after the cancellation. [00115] FIG. 2E illustrates one example of repeated DMRS pattern m case of cancellation of PUSCH transmission with repetition. In the example, PUSCH transmission in the slot# 1 is dropped. Based on this option, UE will resume the repeated DMRS pattern in slot #2. In this case, 4 DMRS symbols are allocated within the slot #0 and #3 and DMRS symbols are not present in the slot #2.

[00116] Note that the above embodiments can be straightforwardly applied and extended for dynamic indication of DMRS patterns for PUCCH and/or PDSCH with and without repetition. For instance, different DMRS patterns can be configured in different PUCCH and/or PDSCH repetitions by higher layers via RMSI (SIB 1), OSI or RRC signalling or dynamically indicated in the DCI. Note that this can be configured per PUCCH format, or per PUCCH resource or per PUCCH resource set.

[00117] In another embodiment set, in case when PUSCH repetitions with intra-slot frequency hopping is enabled with different numbers of DMRS symbols per different hops, even distribution of DMRS overhead across repetitions can be provided by switching of DMRS configurations between hops. When cross-slot channel estimation is used, such scheme helps to ensure channel estimation performance across intra-slot frequency hops.

[00118] In one example, shown on FIG . 2F, if PUSCH mapping Type A, Id = 7 symbols per hop, DMRS initial position lo = 3 and dmrs- AdditionalPosition = pos1 is configured, then one DMRS symbol is used for the 1^st hop and two DMRS symbols are used for the 2^nd hop. As shown on FIG. 2F, to provide evenly distributed DMRS overhead across PUSCH repetition, above configuration (from current specification) can be used for odd transmission occasions or repetitions and inverse configuration with two DMRS symbols for the 1^st hop and one DMRS symbol for the 2^nd hop can be used for even transmission occasions or repetitions.

[00119] In another embodiment, of the disclosure, in case when PUSCH mapping Type B is configured, DMRS symbols can be shared across PUSCH repetitions. In particular, the DMRS symbols in one or more repetitions may not be needed for PUSCH repetition type B. In one example, DMRS is allocated in every N repetition, where DMRS symbols between every N repetition are not used, which can help reduce coding rate and improve decoding performance. [00120] In one option, indication of shared DMRS for PUSCH repetition type B may be configured by RRC signalling, dynamically indicated in the DCI format 0 1 and/or , or a combination thereof. For instance, a set of shared

DMRS patterns can be configured by RRC signaling, where one field in the DCI can be used to dynamically indicate one shared DMRS pattern from the set of shared DMRS patterns. In one example, whether DMRS may be allocated in every 2 or 4 repetitions can be configured by higher layers via RRC signalling. [00121] Note that shared DMRS may be applied for PUSCH repetitions when same frequency resource is applied. In one option, when inter-slot frequency hopping is used, shared DMRS may be applied for the repetition within the same slot. This may apply for the case for actual repetition or nominal PUSCH repetition.

[00122] FIG. 2G illustrates one example of shared DMRS for inter-slot frequency hopping. In the example, it is assumed that starting symbol of first nominal PUSCH repetition is 6 and length of PUSCH repetition is 14 symbols. Further, 2 repetitions are applied for PUSCH transmission. Based on the PUSCH repetition type B, PUSCH repetition is divided into two segments for each repetition due to across slot boundary. In particular, repetition #1-1 and repetition #1-2 are the first and second actual repetition within nominal repetition #1, while repetition #2-1 and repetition #2-2 are the first and second actual repetition within nominal repetition #2. In this case, shared DMRS is applied for repetition #1-2 and #2-1 when inter-slot frequency hopping is used. In particular, DMRS is allocated for repetition #1-2, but not for repetition #2-1. [00123] In another option, when inter-repetition frequency hopping is used, shared DMRS may be applied for the nominal repetition. In case of multiple actual repetitions in a nominal repetition, DMRS in a first actual repetition can be used for the DMRS for the subsequent actual repetitions. In this case, DMRS in the subsequent actual repetitions may not be needed.

[00124] FIG. 2H illustrates one example of shared DMRS for interrepetition frequency hopping. In the example, it is assumed that starting symbol of first nominal PUSCH repetition is 6 and length of PUSCH repetition is 14 symbols. Further, 2 repetitions are applied for PUSCH transmission. Based on the PUSCH repetition type B, PUSCH repetition is divided into two segments for each repetition due to across slot boundary. In particular, repetition #1-1 and repetition #1-2 are the first, and second actual repetition within nominal repetition #1, while repetition #2-1 and repetition #2-2 are the first and second actual repetition within nominal repetition #2, In this case, shared DMRS is applied for repetition #1-1 and #1-2, and repetition #2-1 and #1-2, e.g., within the same nominal repetition, when inter-repetition frequency hopping is used. In particular, DMRS is allocated for repetition #1-1 and #2-1, but not for repetition #1-2 and #2-2.

[00125] Further, in case when a repetition or transmission occasion of the PUSCH transmission is cancelled during the repetition, e.g., due to overlapping of other physical channels or semi-static TDD DL/UL configuration, DMRS can be allocated in the first available PUSCH repetition. In this case, DMRS in the subsequent repetitions may not be needed.

[00126] For semi-static TDD UL/DL configuration, a special slot may be configured, which may include DL symbols, flexible symbols, and uplink symbols. Further, full uplink slots may follow the special slot for TDD system. To further improve the coverage for PUSCH transmission, additional DMRS symbols may be allocated within the uplink symbols of the special slots, which can help in improving channel estimation performance and overall decoding performance.

[00127] FIG. 3 A illustrates one example of allocating additional DMRS symbols in the special slot for associated PUSCH transmission. In the example, one additional DMRS symbol is inserted in the last uplink symbol of special slots before the actual transmission of PUSCH, which can help in improving the channel and frequency offset estimation, and overall decoding performance for PUSCH repetition.

[00128] When additional DMRS symbol(s) is allocated in the special slot, and if the additional DMRS symbols overlap with other uplink transmission, including physical uplink control channel (PUCCH), other PUSCH transmission, and/or sounding reference signal (SRS), certain mechanisms may need to be defined to handle the collision.

[00129] Various embodiments herein include mechanisms of allocating additional DMRS symbols in special slot. For example, aspects of various embodiments include : [00130] Indication of additional DMRS symbols m special slot; and/or [00131] Handling collision between additional DMRS symbols in special slot and other uplink transmissions.

[00132] Embodiments herein may improve coverage of NR PUSCH and/or PUCCH.

[00133] Indication of additional DMRS symbols in special slot

[00134] For semi-static TDD UL/DL configuration, a special slot may be configured, which may include DL symbols, flexible symbols and uplink symbols. Further, full uplink slots may follow the special slot for TDD system. To further improve the coverage for PUSCH transmission, additional DMRS symbols may be allocated within the uplink symbols of the special slots, which can help in improving channel estimation performance and overall decoding performance.

[00135] When additional DMRS symbol(s) is allocated in the special slot, and if the additional DMRS symbols overlap with other uplink transmission, including physical uplink control channel (PUCCH), other PUSCH transmission, and/or sounding reference signal (SRS), certain mechanisms may need to be defined to handle the collision.

[00136] Embodiments of indication of additional DMRS symbols in special slot are provided as follows:

[00137] In one embodiment, indication of additional DMRS symbol(s) in the special slot can be configured by higher layers via minimum system information (MSI), remaining minimum system information (RMSI), other system information (OSI) or dedicated radio resource control (RRC) signalling or dynamically indicated in the downlink control information (DCI) or a combination thereof. Note that this indication may only apply for unpaired spectrum or for the case when semi-static TDD UL/DL configuration is configured.

[00138] In one option, indication of additional DMRS symbol(s) in the special slot can be configured by higher layers via RRC signalling for unpaired spectrum. Further, UE only transmits when the number of repetitions is larger than N and/or when PUSCH repetition is transmitted in the uplink slot right after the special slot. Note that N can be predefined in the specification or configured by higher layers via minimum system information (MSI), remaining minimum system information (RMSI ). other system information (OST) or dedicated radio resource control (RRC) signalling. For instance, N = 2.

[00139] In one example, a new position for DMRS symbols in the special slot, “pos4” may be configured for PUSCH transmission. When pos4 is configured, e.g., indicated with “-l”m DMRS symbols are transmitted in the special slot for the corresponding PUSCH transmission.

[00140] In another option, for configured grant PUSCH (CG-PUSCH), or PUSCH transmission without associated DC I, indication of additional DMRS symbol(s) in the special slot is configured by higher layers as part of configured grant configuration.

[00141] Yet in another option, for PUSCH scheduled by a non-fallback DCI format, including DCI format 0 1 and/or 0 2, additional DMRS symbol(s) can be inserted in the special slot if configured or indicated and the above conditions are met. For PUSCH scheduled by a fallback DCI format, e.g., DCI format 0_0, additional DMRS symbol(s) are not inserted in the special slot.

[00142] In one embodiment, one or more than one DMRS symbols can be allocated in the last symbol(s) in the special slots. This may also depend on whether double symbol is used for associated PUSCH transmission. In particular, if double symbol DMRS is configured or indicated for associated PUSCH transmission, double symbol DMRS can be allocated in the special slot. In addition, if single symbol DMRS is configured or indicated for associated PUSCH transmission, single symbol DMRS can be allocated in the special slot.

[00143] Further, same DMRS AP is used for the transmission of DMRS in special slot and in uplink slot for PUSCH transmission. The DMRS AP is indicated by DMRS AP in the DCI for scheduling PUSCH transmission or configured by higher layers for CG-PUSCH transmission.

[00144] In one option, if the higher-layer parameter maxi length in DMRS- UplinkConfig is equal to 'len2', and if the associated DCI or configured grant configuration determines double-symbol DM-RS is used, if configured, double symbol DMRS can be located in the special slot for the associated PUSCH transmission. Further, if the associated DCI or configured grant configuration determines single-symbol DM-RS is used, if configured, single-symbol DMRS can be located in the special slot for the associated PUSCH transmission. [00145] In another option, if single symbol DMRS is configured or indicated for associated PUSCH transmission, more than one single symbol DMRS or K single symbol DMRS can be located in the special slot for the PUSCH transmission, where K can be configured by higher layers via MSI, RMSI (SIBl), OSI or RRC signalling.

[00146] As a further extension, when the number of UL symbols in special slot is less than the double symbol or less than the configured number of symbols for single symbol DMRS, in one option, the DMRS symbol(s) in special slot is dropped. Alternatively, when the number of UL symbols in special slot is less than the configured number of symbols for single symbol DMRS, DMRS symbol(s) are only transmitted in the uplink symbols in the special slots and the remaining DMRS symbol(s) are dropped.

[00147] FIG. 3B illustrates one example of double symbol DMRS located in the special slot. In the example, maxLength in DMRS-UplinkConfig is equal to 'len2', and antenna port in the DCI indicates that double symbol DMRS is used for associated PUSCH transmission. In this case, if configured, double symbol DMRS is also transmitted in the special slot.

[00148] In another embodiment, indication of additional DMRS symbol(s) in the special slot can be dynamically indicated in the DCI.

[00149] In one option, one field in the DCI may be included in the DCI format 0_l and/or 0__2 to indicate whether additional DMRS symbol(s) are located in the special slot for the associated PUSCH transmission. In particular, bit "1" may be used to indicate that additional DMRS symbol(s) are located in the special slot for the associated PUSCH transmission; while bit “0” may be used to indicate that additional DMRS symbol(s) are not located in the special slot for the associated PUSCH transmission.

[00150] In another option, some reserved fields in the antenna port field in the DCI may be used to indicate whether additional DMRS symbol (s) are located in the special slot for the associated PUSCH transmission.

[00151] In one example, reserved states from Table 7.3.1.1 .2-7 from TS 38.212 can be used for indication of presence of additional DMRS symbol(s) in the special slot. Example of the enhanced table is provided below; where changes are indicated in underline: [00152] Table 7.3.1 , 1 .2-7 : Antenna port(s), transform precoder i s enabled, dmrs-Type=1, maxLength=2, except that dmrs-UplinkTransformPrecoding-r 16 and tp-pi2BPSK are both configured and -BPSK modulation is used

00153] [00154] In another example, whether additional DMRS symbol(s) are transmitted in the special slot can be included as a part, of antenna port configuration port. Note that this option may be applied for the case when less than 5 bits indication is used for antenna port configuration . The update of part of section 7.3.1.1.2 in TS 38.212 is indicated in underline: [00155] Antenna ports - number of bits determined by the following

[00156] - 3 in total, 3 bits as defined by Tables 7.3.1.1.2-6, if transform precoder is enabled,

and

, except that dmrs- UplinkTransformPrecoding-rl6 and tp-pi2BPSK are both configured and

BPSK modulation is used: and 1 bit for indication of additional PAIRS symbol(s) in the special slot [00157] - 3 in total, 2 bits as defined by Tables 7.3. 1 .1.2-6 A, it transform precoder is enabled and dmrsUplinkTransformPrecoding-r 16 and tp-pi2BPSK are both configured,

BPSK modulation is used,

_: and

, where nSCID is the scrambling identity for antenna ports defined in [Clause 6.4.1.1. 1.2, TS38.211]; and 1 bit for indication of additional DAIRS symbol(s) in the special slot

[00158] - 5 in total, 4 bits as defined by Tables 7.3.1.1.2-7, if transform precoder is enabled, dmrs-Type=1 , and maxLength =2, except that dmrs-

and tp-pi2BPSK are both configured and

BPSK modulation i s used; and 1 bit for indication of additional DMRS symbol(s) in the special slot

[00159] - 5 in total, 4 bits as defined by Tables 7.3.1.1.2-7 A, if transform precoder is enabled and dmrsUplinkTransformPrecoding-r 16 and tp-pi2BPSK are both configured,

BPSK modulation is used,

yp , and maxLength= 2, where nSCID is the scrambling identity for antenna ports defined in [Clause 6.4. 1.1.1.2, TS38.211]; and 1 bit for indication of additional PAIRS symbol(s) in the special slot

[00160] - 4 in total, 3 bits as defined by Tables 7.3. 1.1.2-8/9/10/11, if transform precoder is disabled,

, and

, and the value of rank is determined according to the SRS resource indicator field if the higher layer parameter and according to the Precoding

information and number of layers field if the higher layer parameter txConfig -- codebook, and 1 bit for indication of additional DMRS symbol (s) in the special slot

[00161] - 5 in total, 4 bits as defined by Tables 7.3. 1.1 .2-12/13/14/15, if transform precoder is disabled,

, and maxLength=2, and the value of rank is determined according to the SRS resource indicator field if the higher layer parameter txConfig nonCodebook and according to the Preceding information and number of layers field if the higher layer parameter txConfig = codebook, and 1 bit for indication of additional DMRS symbol(s) in the special slot

[00162] - 5 in total, 4 bits as defined by Tables 7.3.1 .1.2-16/17/18/19, if transform precoder is disabled,

yp , and and the value

of rank is determined according to the SRS resource indicator field if the higher layer parameter txConfig = nonCoaebook and according to the Precoding information and number of layers field if the higher layer parameter txConfig --- codebook,’ and 1 bit for indication of additional DMRS svmbol(s) in the special slot

[00163] - 5 bits as defined by Tables 7.3.1.1.2-20/21/22/23 , if transform precoder is disabled, dmrs-Type=2, and maxLengtlr=2, and the value of rank is determined according to the SRS resource indicator field if the higher layer parameter

and according to the Precoding information and number of layers field if the higher layer parameter

[00164] In another embodiment, the above embodiments can also apply for the PUCCH transmission or repetition. In particular, the indication on whether additional DMRS symbol(s) in the special slot can be configured by higher layers via MSI, RMSI (SIB 1), OSI or RRC signalling or dynamically indicated in the DCI or a combination of thereof,

[00165] Handling collision between additional DMRS symbols in special slot and other uplink transmissions

[00166] Embodiments of handling collision between additional DMRS symbols in special slot and other uplink transmissions are provided as follows: [00167] In one embodiment, when the additional DMRS symbol(s) in the special slot overlaps with other uplink transmissions including a physical uplink control channel (PUCCH), another PUSCH transmission, sounding reference signal (SRS), and/or physical random-access channel (PRACH), the overlapped DMRS symbols are dropped, and UE transmits other uplink signals/channels in the overlapped symbols.

[00168] FIG. 3C illustrates one example of handling overlapping between additional DMRS symbols and SRS in accordance with the above option. In the example, last symbol in the special slot is allocated for the additional DMRS symbol, which overlaps with the SRS transmission. In this example, the additional DMRS symbol is dropped, and UE transmits SRS in the overlapped symbols.

[00169] In another option, in case when double symbol DMRS is located in the special slot for the associated PUSCH transmission, and when the double symbol DMRS overlaps with other uplink signals/channels at least in one symbol, the whole double symbol DMRS is dropped, and UE transmits other uplink signal s/chann els in the overlapped symbols.

[00170] In another options, the additional DMRS syrnbol(s) in the special slot overlaps with other uplink channel s/signals, the overlapped DMRS symbols are transmitted, and UE cancels the other uplink signal s/channels in the overlapped symbols. Further, for PUSCH, PUCCH and PRACH, the cancellation unit is the whole transmission, while for SRS, the cancellation unit is the overlapped symbol. In this case, when the additional DMRS symbol(s) in the special slot overlaps with SRS, SRS is only dropped in the overlapped symbols and the other symbols for SRS are still transmitted.

[00171] FIG. 3D illustrates one example of handling overlapping between additional DMRS symbols and SRS in accordance with the above option. In the example, last symbol in the special slot is allocated for the additional DMRS symbol, which overlaps with the SRS transmission. In this example, the additional DMRS symbol is transmitted. In addition, UE transmits the SRS in the non-overlapping symbols and drops the SRS in the overlapped symbols, e.g., last symbol in the special slot.

[00172] In another embodiment, when the additional DMRS symbol(s) in the special slot overlaps with a physical uplink control channel (PUCCH), and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, the overlapped additional DMRS symbols are dropped and the PUCCH is transmitted in the special slot. Note that the timeline requirement is defined at the start of the additional DMRS symbols in the special slot associated with the PUSCH transmission.

[00173] In addition, if more than one symbols in the special slots are allocated for the additional DMRS, and when a subset of the DMRS symbols overlap with PUCCH in the special slot, the overlapped DMRS symbols are dropped and the remaining DMRS symbol(s) is transmitted in the special slot.

[00174] FIG. 3E illustrates one example of handling overlapping between additional DMRS symbols and PUCCH in accordance with the above option. In the example, last symbol in the special slot is allocated for the additional DMRS symbol, which overlaps with the PUCCH transmission. If the timeline requirement is satisfied, the additional DMRS symbol is dropped and the PUCCH is transmitted in the special slot, [00175] In another embodiment, when the additional DMRS symbol(s) in the special slot overlaps with a PUCCH, and if the timeline requirement as defined in Section 9/2.5 in TS38.2I3 is satisfied, the PUCCH is dropped and the additional DMRS symbol(s) are transmited.

[00176] FIG. 3F illustrates one example of handling overlapping between additional DMRS symbols and PUCCH in accordance with the above option. In the example, last symbol in the special slot is allocated for the additional DMRS symbol, which overlaps with the PUCCH transmission. If the timeline requirement is satisfied, the PUCCH is dropped and the additional DMRS symbol is transmitted in the special slot.

[00177] In another embodiment, when the additional DMRS symbol(s) in the special slot overlaps with a PUCCH carrying tiplink control information (UCI), and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, the PUCCH is dropped and the additional DMRS symbol(s) are transmited. Further, the UCI is multiplexed on the PUSCH.

[00178] FIG. 3G illustrates one example of handling overlapping between additional DMRS symbols and PUCCH in accordance with the above option. In the example, last symbol in the special slot is allocated for the additional DMRS symbol, which overlaps with the PUCCH transmission. If the timeline requirement is satisfied, the PUCCH is dropped and the additional DMRS symbol is transmitted in the special slot. Further, the UCI is multiplexed on the PUSCH.

[00179] In another embodiment, when the additional DMRS symbol(s) in the special slot overlaps with a PUCCH cartying uplink control information (UCI), and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, whether to drop the additional DMRS symbols or PUCCH may depend on the priority of UCI carried by the PUCCH.

[00180] In one option, when a PUCCH cartying hybrid automatic repeat request - acknowledgement (HARQ-ACK) feedback or scheduling request (SR) overlaps the additional DMRS symbol(s) in the special slot, the additional DMRS(s) in the special slot is dropped and the PUCCH is transmitted.

[00181] In another option, when a PUCCH carrying channel state information (CSI) report overlaps with the additional DMRS symbol(s) in the special slot, the additional DMRS(s) in the special slot is transmitted and the PUCCH is dropped. Note that other permutation of priority order can be straightforwardly extended from the aforementioned options.

[00182] In another embodiment, when the additional DMRS symbol(s) in the special slot overlaps with other uplink channel s/signals, whether to drop the additional DMRS symbol(s) in the special slot or the other uplink channel s/signals may depend on the priority of associated PUSCH transmission and other uplink signals/channels.

[00183] In one option, if lower priority is configured or indicated for the transmission of the additional DMRS symbol(s) in the special slot and associated PUSCH, and if higher priority is configured or indicated for the transmission of the other uplink channel s/signals, and when the additional DMRS symbol(s) in the special slot overlaps with other uplink channel s/signals, the additional DMRS symbol(s) in the special slot is dropped and UE transmits the other uplink channel s/signals with higher priority.

[00184] In another option, if higher priority is configured or indicated for the transmission of the additional DMRS symbol(s) in the special slot and associated PUSCH, and if lower priority is configured or indicated for the transmission of the other uplink channel s/signals, and when the additional DMRS symbol(s) in the special slot overlaps with other uplink channel s/signals, the additional DMRS symbol(s) in the special slot is transmitted and UE cancels the other uplink channel s/signals with lower priority.

[00185] In another option, the additional DMRS symbol(s) in the special slot and associated PUSCH are defined with lower priority, and when the additional DMRS symbol(s) in the special slot overlaps with other uplink channel s/signals with higher priority, the additional DMRS symbol(s) in the special slot is dropped and UE transmits the other uplink channels/signals with higher priority.

[00186] In another embodiment, the above embodiments can also apply for the transmission of PUCCH with or without repetition. In one example, when the additional DMRS symbol(s) in the special slot overlaps with other uplink transmissions including a physical uplink control channel (PUCCH), another PUSCH transmission, sounding reference signal (SRS), and/or physical randomaccess channel (PRACH), the overlapped DMRS symbols are dropped, and UE transmits other uplink signals/channels in the overlapped symbols. [00187] FIG. 4 illustrates a functional block diagram of a wireless communication device, in accordance with some embodiments. In some embodiments, FIG. 4 illustrates a functional block diagram of user equipment (UE). In some embodiments, FIG. 4 illustrates a functional block diagram of a gNB. The communication device 400 may also be suitable for use as a handheld device, a mobile device, a cellular telephone, a smartphone, a tablet, a netbook, a wireless terminal, a laptop computer, a wearable computer device, a femtocell, a high data rate (HDR) subscriber device, an access point, an access terminal, or other personal communication system (PCS) device.

[00188] The communication device 400 may include communications circuitry 402 and a transceiver 410 for transmitting and receiving signals to and from other communication devices using one or more antennas 401. The communications circuitry 402 may include circuitry that can operate the physical layer (PHY) communications and/or medium access control (MAC) communications for controlling access to the wireless medium, and/or any other communications layers for transmitting and receiving signals. The communication device 400 may also include processing circuitry 406 and memory 408 arranged to perform the operations described herein. In some embodiments, the communications circuitry 402 and the processing circuitry 406 may be configured to perform operations detailed in the above figures, diagrams, and flows.

[00189] In accordance with some embodiments, the communications circuitry 402 may be arranged to contend for a wireless medium and configure frames or packets for communicating over the wireless medium. The communications circuitry' 402 may be arranged to transmit and receive signals. The communications circuitry' 402 may also include circuitry' for m odul ation/dem odul ation, upconver si on/ downcon ver si on, fil tering, amplification, etc. In some embodiments, the processing circuitry 406 of the communication device 400 may include one or more processors. In other embodiments, two or more antennas 401 may be coupled to the communications circuitry-' 402 arranged for sending and receiving signals. The memory 408 maystore information for configuring the processing circuitry 406 to perform operations for configuring and transmitting message frames and performing the various operations described herein. The memory 408 may include any type of memory, including non-transitory memory, for storing information m a form readable by a machine (e.g., a computer). For example, the memory 408 may include a computer-readable storage device, read-only memory (ROM), randomaccess memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices and other storage devices and media.

[00190] In some embodiments, the communication device 400 may be part of a portable wireless communication device, such as a personal digital assistant (PDA ), a laptop or portable computer with wireless communication capability, a web tablet, a wireless telephone, 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 may receive and/or transmit information wirelessly.

[00191] In some embodiments, the communication device 400 may include one or more antennas 401 . The antennas 401 may include one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmission of RF signals. In some embodiments, instead of two or more antennas, a single antenna with multiple apertures may be used. In these embodiments, each aperture may be considered a separate antenna. In some multiple-input multiple-output (MIMO) embodiments, the antennas may be effectively separated for spatial diversity and the different channel characteristics that may result between each of the antennas and the antennas of a transmitting device.

[00192] In some embodiments, the 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, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen.

[00193] Although the communication device 400 is illustrated as having several separate functional elements, two or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as 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 circuitry for performing at least the functions described herein. In some embodiments, the functional elements of the communication device 400 may refer to one or more processes operating on one or more processing elements. [00194] [00195]

[00196] EXAMPLE SET 1

[00197] Example 1 may include the system and method of wireless communication for a fifth generation (5G) or new radio (NR) system:

[00198] Configured, by gNB, a set of demodulation reference signal (DMRS) patterns over one or more physical uplink shared channel (PUSCH) transmission occasions or repetitions,

[00199] Indicated, by gNB, a DMRS pattern over one or more PUSCH transmission occasions or repetitions from the configured set of DMRS patterns. [00200] Example 2 may include the method of example 1 or some other example herein, wherein different DMRS patterns or configurations including PUSCH mapping type, the number of DMRS symbols and positions of DMRS symbols may be used in one or more repetitions for PUTSCH transmission.

[00201] Example 3 may include the method of example 2 or some other example herein, wherein a first DMRS configuration or pattern including number of DMRS symbols and DMRS position is configured in a first PUSCH repetition or transmission occasion or slot, while a second DMRS configuration or pattern is configured in a second PUSCH repetition or transmission occasion or slot.

[00202] Example 4 may include the method of example 2 or some other example herein, wherein the first DMRS configuration or pattern in the first PUSCH repetition or transmission occasion or slot may include a greater number of DMRS symbols than the second DMRS configuration or pattern in the second PUSCH repetition or transmission occasion or slot.

[00203] Example 5 may include the method of example 2 or some other example herein, wherein the second DMRS configuration or pattern may not include DMRS symbols m the second PUSCH repetition or transmission occasion or slot.

[00204] Example 6 may include the method of example 1 or some other example herein, wherein a set of DMRS configurations or patterns over one or more PUSCH repetitions or slots can be predefined in the specification or configured by higher layers via minimum system information (MSI), remaining minimum system information (RMSI), other system information (OSI) or dedicated radio resource control (RRC) signalling or dynamically indicated in medium access control - control element (MAC-CE) or a downlink control information (DCI) or a combination thereof.

[00205] Example 7 may include the method of example 1 or some other example herein, wherein for PUSCH scheduled by a DCI format 0 1 and/or 0 2, a set of DMRS configurations or patterns over one or more PUSCH repetitions or slots can be configured by dedicated RRC signalling, wherein one field in the DCI format 0_l and/or 0__2 can be used to indicate one DMRS configuration or pattern over one or more PUSCH repetitions or slots from the set of configured DMRS configurations or patterns.

[00206] Example 8 may include the method of example 1 or some other example herein, wherein for configured grant PUSCH, a DMRS configuration or pattern over one or more PUSCH repetitions or slots can be configured by higher layers via dedicated RRC signalling when PUSCH repetition is configured.

[00207] Example 9 may include the method of example 1 or some other example herein, wherein for PUSCH scheduled by fallback DCI or DCI format 0_0 or random-access response (RAR) uplink grant or fallback RAR uplink grant, DMRS configuration or pattern over one slot or transmission occasion is used.

[00208] Example 10 may include the method of example 1 or some other example herein, wherein dmrs-AdditionalPosition parameter in DMRS- UplinkConfig can be extended to indicate more than one additional DMRS positions which correspond to PUSCH in different repetitions or transmission occasions or slots.

[00209] Example 1 1 may include the method of example 1 or some other example herein, wherein a new⁷ RRC parameter or existing parameter dmrs- AdditionalPosition can be used to indicate one row from a configured or predefined table for a set of DMRS configurations or patterns.

[00210] Example 12 may include the method of example 1 or some other example herein, wherein when the number of repetitions for PUSCH transmission is larger than the size of the set of configured DMRS patterns, the set of configurated DMRS patterns repeats across the PUSCH repetition.

[00211] Example 13 may include the method of example 1 or some other example herein, wherein in case when a repetition or transmission occasion of the PUSCH transmission is cancelled during the repetition, the repeated DMRS pattern is continued regardless of whether one PUSCH repetition or transmission occasion is dropped.

[00212] Example 14 may include the method of example 1 or some other example herein, wherein when a PUSCH repetition or transmission occasion is cancelled during the repetition, the repeated DMRS pattern is resumed after the cancellation.

[00213] Example 15 may include the method of example 1 or some other example herein, wherein the above embodiments can be straightforwardly applied and extended for dynamic indication of DMRS patterns for PUCCH repetition.

[00214] Example 16 may include the method of example 1 or some other example herein, wherein when PUSCH repetitions with intra-slot frequency hopping is enabled with different numbers of DMRS symbols per different hops, even distribution of DMRS overhead across repetitions can be provided by switching of DMRS configurations between hops.

[00215] Example 17 may include the method of example 1 or some other example, wherein when PUSCH mapping Type B is configured, DMRS symbols can be shared across PUSCH repetitions; wherein DMRS symbols in one or more repetitions may not be needed for PUSCH repetition type B.

[00216] Example 18 may include the method of example 1 or some other example herein, wherein indication of shared DMRS for PUSCH repetition type B may be configured by RRC signalling, dynamically indicated in the DCI format 0__l and/or 0_2, or a combination thereof. [00217] Example 19 may include the method of example 1 or some other example herein, wherein when inter-slot frequency hopping is used, shared DMRS may be applied for the repetition within the same slot.

[00218] Example 20 may include the method of example 1 or some other example herein, wherein when inter-repetition frequency hopping is used, shared DMRS may be applied for the nominal repetition.

[00219] Example 21 may include a method comprising: determining that PUSCH repetitions with intra-slot frequency hopping is enabled with different numbers of DMRS symbols per different hops; and based on the determination, evenly distributing DMRS overhead across repetitions.

[00220] Example 22 may include the method of example 21 or some other example herein, wherein the evenly distributing includes switching of DMRS configurations between hops.

[00221] Example 23 may include the method of example 21-22 or some other example, wherein when PUSCH mapping Type B is configured, sharing DMRS symbols across PUSCH repetitions.

[00222] Example 24 may include the method of example 23 or some other example herein, further comprising omitting DMRS symbols in one or more of the repetitions.

[00223] Example 25 may include the method of example 23-24 or some other example herein, further comprising receiving an indication of the shared DMRS for PUSCH repetition type B via RRC signalling, DCI (e.g., DCI format and/or ), or a combination thereof.

[00224] Example 26 may include the method of example 21-25 or some other example herein, wherein inter-slot frequency hopping is used for the repetitions, and wherein the method further comprises applying shared DMRS for repetitions within a same slot.

[00225] Example 27 may include the method of example 21-26 or some other example herein, wherein inter-repetition frequency hopping is used, and wherein the method further comprises applying a shared DMRS for a nominal repetition.

[00226] Example 28 may include an apparatus comprising means to perform one or more elements of a method described in or related to any of examples 1-27, or any other method or process described herein. [00227] Example 29 may include one or more non-transitory computer- readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of a method described in or related to any of examples 1-27, or any other method or process described herein.

[00228] Example 31 may include an apparatus comprising logic, modules, or circuitry to perform one or more elements of a method described in or related to any of examples 1-27, or any other method or process described herein.

[00229] Example 32 may include a method, technique, or process as described in or related to any of examples 1-27, or portions or parts thereof [00230] Example 33 may include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform the method, techniques, or process as described in or related to any of examples 1-27, or portions thereof.

[00231] Example 34 may include a signal as described in or related to any of examples 1-27, or portions or parts thereof.

[00232] Example 35 may include a datagram, packet, frame, segment, protocol data unit (PDU), or message as described in or related to any of examples 1-27, or portions or parts thereof, or otherwise described in the present disclosure.

[00233] Example 36 may include a signal encoded with data as described in or related to any of examples 1-27, or portions or parts thereof, or otherwise described in the present disclosure.

[00234] Example 37 may include a signal encoded with a datagram, packet, frame, segment, protocol data unit (PDU), or message as described in or related to any of examples 1-27, or portions or parts thereof, or otherwise described in the present disclosure.

[00235] Example 38 may include an electromagnetic signal carrying computer-readable instructions, wherein execution of the computer-readable instructions by one or more processors is to cause the one or more processors to perform the method, techniques, or process as described in or related to any of examples 1-27, or portions thereof. [00236] Example 39 may include a computer program composing instructions, wherein execution of the program by a processing element is to cause the processing element to carry out the method, techniques, or process as described in or related to any of examples 1-27, or portions thereof.

[00237] Example 40 may include a signal in a wireless network as shown and described herein.

[00238] Example 41 may include a method of communicating in a wireless network as shown and described herein.

[00239] Example 42 may include a system for providing wireless communication as shown and described herein.

[00240] Example 43 may include a device for providing wireless communication as shown and described herein.

[00241] EXAMPLE SET 2

[00242] Example 1 may include a method of wireless communication comprising:

[00243] receiving, by a UE from a gNodeB (gNB), an indication of one or more than one demodulation reference signal (DMRS) symbols in a special slot associated with a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH) in a next uplink slot in unpaired spectrum; and [00244] transmitting, by the UE, the one or more than one DMRS symbols in the special slot and the associated PUSCH or PUCCH in the next uplink slot in accordance with the indication.

[00245] Example 2 may include the method of example 1 or some other example herein, wherein indication of additional DMRS symbol(s) in the special slot can be configured by higher layers via minimum system information (MSI), remaining minimum system information ( RMSI), other system information (OSI) or dedicated radio resource control (RRC) signalling or dynamically indicated in the downlink control information (DCI) or a combination thereof. [00246] Example 3 may include the method of example 1 or some other example herein, wherein UE only transmits when the number of repetitions is larger than N and/or when PUSCH repetition is transmitted in the uplink slot right after the special slot, wherein N can be predefined in the specification or configured by higher layers. [00247] Example 4 may mclude the method of example I or some other example herein, wherein for configured grant PUSCH (CG-PUSCH), or PUSCH transmission without associated DCI, indication of additional DMRS symbol(s) in the special slot is configured by higher layers as part of configured grant configuration.

[00248] Example 5 may include the method of example 1 or some other example herein, wherein one or more than one DMRS symbols can be allocated in the last symbol(s) in the special slots.

[00249] Example 6 may include the method of example 1 or some other example herein, wherein same DMRS AP is used for the transmission of DMRS in special slot and in uplink slot for PUSCH transmission. The DMRS AP is indicated by DMRS AP in the DCI for scheduling PUSCH transmission or configured by higher layers for CG-PUSCH transmission.

[00250] Example 7 may include the method of example 1 or some other example herein, wherein when the number of UL symbols in special slot is less than the double symbol or less than the configured number of symbols for single symbol DMRS, in one option, the DMRS symbol(s) in special slot is dropped.

[00251] Example 8 may include the method of example 1 or some other example herein, wherein if double symbol DMRS is configured or indicated for associated PUSCH transmission, double symbol DMRS can be allocated in the special slot; wherein if single symbol DMRS is configured or indicated for associated PUSCH transmission, single symbol DMRS can be allocated in the special slot.

[00252] Example 9 may include the method of example I or some other example herein, wherein if single symbol DMRS is configured or indicated for associated PUSCH transmission, more than one single symbol DMRS or K single symbol DMRS can be located in the special slot for the PUSCH transmission, where K can be configured by higher layers via MSI, RMSI (SIB1), OSI or RRC signalling.

[00253] Example 10 may include the method of example 1 or some other example herein, wherein indication of additional DMRS symbol(s) in the special slot can be dynamically indicated in the DCI.

[00254] Example 11 may include the method of example 1 or some other example herein, wherein when the additional DMRS symbol(s) in the special slot overlaps with other uplmk transmissions including a physical uplink control channel (PUCCH), another PUSCH transmission, sounding reference signal (SRS), and/or physical random-access channel (PRACH), the overlapped DMRS symbols are dropped, and UE transmits other uplink signals/channels in the overlapped symbols.

[00255] Example 12 may include the method of examples 1 or some other example herein, wherein case when double symbol DMRS is located in the special slot for the associated PUSCH transmission, and when the double symbol DMRS overlaps with other uplink signals/channels at least in one symbol, the whole double symbol DMRS is dropped, and UE transmits other uplink signals/channels in the overlapped symbols.

[00256] Example 13 may include the method of example 1 or some other example herein, wherein when the additional DMRS symbol(s) in the special slot overlaps with a physical uplink control channel (PUCCH), and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, the overlapped additional DMRS symbols are dropped and the PUCCH is transmitted in the special slot.

[00257] Example 14 may include the method of example 1 or some other example herein, wherein more than one symbols in the special slots are allocated for the additional DMRS, and when a subset of the DMRS symbols overlap with PUCCH in the special slot, the overlapped DMRS symbols are dropped and the remaining DMRS symbol(s) is transmitted in the special slot.

[00258] Example 15 may include the method of example 1 or some other example herein, wherein when the additional DMRS symbol(s) in the special slot overlaps with a PUCCH, and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, the PUCCH is dropped and the additional DMRS symbol(s) are transmited.

[00259] Example 16 may include the method of example 1 or some other example herein, wherein when the additional DMRS symbol(s) in the special slot overlaps with a PUCCH carrying uplink control information (UCI), and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, the PUCCH is dropped and the additional DMRS symbol (s) are transmitted. Further, the UCI is multiplexed on the PUSCH. [00260] Example 17 may include the method of example 1 or some other example herein, wherein when the additional DMRS symbol(s) in the special slot overlaps with a PUCCI! carrying uplink control information (UCI), and if the timeline requirement as defined in Section 9.2.5 in TS38.213 is satisfied, whether to drop the additional DMRS symbols or PUCCH may depend on the priority of UCI carried by the PUCCH.

[00261] Example 18 may include the method of example 1 or some other example herein, wherein when the additional DMRS symbol(s) in the special slot overlaps with other uplink channel s/signals, whether to drop the additional DMRS symbol(s) in the special slot or the other uplink channels/ signals may depend on the priority of associated PUSCH transmission and other uplink signal s/chann el s.

[00262] Example 19 may include the method of example 1 or some other example herein, wherein if lower priority is confi gured or indicated for the transmission of the additional DMRS symbol(s) in the special slot and associated PUSCH, and if higher priority is configured or indicated for the transmission of the other uplink channel s/signals, and when the additional DMRS symbol(s) in the special slot overlaps with other uplink channel s/signals, the additional DMRS symbol(s) in the special slot is dropped and UE transmits the other uplink channel s/signals with higher priority.

[00263] Example 20 may include the method of example 1 or some other example herein, wherein if higher priority is configured or indicated for the transmission of the additional DMRS symbol(s) in the special slot and associated PUSCH, and if lower priority is configured or indicated for the transmission of the other uplink channel s/signals, and when the additional DMRS symbol(s) in the special slot overlaps with other uplink channel s/signals, the additional DMRS symbol(s) in the special slot is transmitted and UE cancels the other uplink channel s/signals with lower priority.

[00264] Example 21 may include a method of a UE, the method comprising:

[00265] receiving, from a gNodeB (gNB), an indication of one or more demodulation reference signal (DMRS) symbols in a special slot associated with a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH) to be transmitted in a next uplink slot in unpaired spectrum; and [00266] encoding, for transmission, the one or more DMRS symbols in the special slot and the associated PUSCH or PUCCH in the next uplink slot in accordance with the indication.

[00267] Example 22 may include the method of example 21 or some other example herein, wherein the indication of the one or more DMRS symbol in the special slot is received via minimum system information (MSI), remaining minimum system information (RMSI), other system information (OSI) dedicated radio resource control (RRC) signalling, a downlink control information (DCI), or a combination thereof.

[00268] Example 23 may include the method of example 21-22 or some other example herein, wherein the one or more DMRS symbols are transmitted based on a determination that a number of repetitions is larger than N and/or when PUSCH repetition is transmitted in the uplink slot right after the special slot.

[00269] Example 24 may include the method of example 23 or some other example herein, wherein a value of N is predefined.

[00270] Example 25 may include the method of example 23 or some other example herein, further comprising receiving a configuration of a value of N.

[00271] Example 26 may include the method of example 21-25 or some other example herein, wherein the indication of the one or more DMRS symbols is included in a configured grant configuration associated with the PUSCH.

[00272] Example 27 may include the method of example 21-26 or some other example herein, wherein the one or more DMRS symbols are allocated in the one or more last symbols in the special slot.

[00273] Example 28 may include the method of example 21-27 or some other example herein, wherein a same DMRS AP is used for the transmission of one or more DMRS symbols in the special slot and for the transmission of the PUSCH in the uplink slot.

[00274] Example 29 may include the method of example 28 or some other example herein, wherein the DMRS AP is indicated by a DMRS AP in a DCI that schedules the PUSCH.

[00275] Example 30 may include the method of example 28 or some other example herein, wherein the DMRS AP is configured by higher layers and the PUSCH is a configured grant PUSCH. [00276] Example 31 may include the method of example 21-30 or some other example herein, wherein the DMRS symbols in the special slot are dropped if a number of UL symbols in the special slot is less than a double symbol DMRS or less than a configured number of symbols for single symbol DMRS. [00277] Example 32 may include the method of example 21-31 or some other example herein, wherein if double symbol DMRS is configured or indicated for the associated PUSCH transmission, double symbol DMRS is allocated in the special slot, and wherein if single symbol DMRS is configured or indicated for the associated PUSCH transmission, single symbol DMRS is allocated in the special slot.

[00278] Example 33 may include a method of a gNB, the method comprising:

[00279] encoding, for transmission to a UE, an indication of one or more demodulation reference signal (DMRS) symbols in a special slot associated with a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH) to be transmitted in a next uplink slot in unpaired spectrum; and [00280] receiving the one or more DMRS symbols in the special slot and the associated PUSCH or PUCCH in the next uplink slot in accordance with the indication.

[00281] Example 34 may include the method of example 33 or some other example herein, wherein the indication of the one or more DMRS symbol in the special slot is transmitted via minimum system information (MSI), remaining minimum system information (RMSI), other system information (OSI) dedicated radio resource control (RRC) signalling, a downlink control information (DCI), or a combination thereof.

[00282] Example 35 may include the method of example 33-34 or some other example herein, wherein the one or more DMRS symbols are received based on a determination that a number of repetitions is larger than N and/or when PUSCH repetition is transmitted in the uplink slot right after the special slot.

[00283] Example 36 may include the method of example 35 or some other example herein, wherein a value of N is predefined.

[00284] Example 37 may include the method of example 35 or some other example herein, further compri sing receiving a configuration of a value of N. [00285] Example 38 may include the method of example 33-37 or some other example herein, wherein the indication of the one or more DMRS symbols is included in a configured grant configuration associated with the PUSCH.

[00286] Example 39 may include the method of example 33-38 or some other example herein, wherein the one or more DMRS symbols are allocated in the one or more last symbols in the special slot.

[00287] Example 40 may include the method of example 33-39 or some other example herein, wherein a same DMRS AP is used for the reception of one or more DMRS symbols in the special slot and for the reception of the PUSCH in the uplink slot.

[00288] Example 41 may include the method of example 40 or some other example herein, wherein the DMRS AP is indicated by a DMRS AP in a DC I that schedules the PUSCH.

[00289] Example 42 may include the method of example 40 or some other example herein, wherein the DMRS AP is configured by higher layers and the PUSCH is a configured grant PUSCH.

[00290] Example 43 may include the method of example 33-42 or some other example herein, wherein the DMRS symbols in the special slot are dropped if a number of UL symbols in the special slot is less than a double symbol DMRS or less than a configured number of symbols for single symbol DMRS. [00291] Example 44 may include the method of example 33-43 or some other example herein, wherein if double symbol DMRS is configured or indicated for the associated PUSCH transmission, double symbol DMRS is allocated in the special slot; and wherein if single symbol DMRS is configured or indicated for the associated PUSCH transmission, single symbol DMRS is allocated in the special slot.

[00292] Any of the above-described examples may be combined wi th any other example (or combination of examples), unless explicitly stated otherwise. The foregoing description of one or more implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of embodiments to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of various embodiments. [00293] The Abstract is provided to comply with 37 C.F.R. Section

1.72(b) requiring an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims. The following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment.

Claims

CLAIMS What is claimed is:

1. An apparatus for a user equipment (UE) configured for operation in a fifth -generation (5G) new radio (NR) network, the apparatus comprising: processing circuitry; and memory, wherein for unpaired spectrum operation, the UE is configured with a semi-static uplink/downlink (UL/DL) configuration comprising a plurality of slots including uplink slots, downlink slots and special slots, wherein at least some of the special slots precede the uplink slots, wherein the processing circuitry is configured to: determine PUSCH DM-RS positions within the uplink slots for transmission of a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH); decode configuration information received from a generation Node B (gNB) to indicate if additional DMRS are to be transmitted in the special slots that precede the uplink slots of the UL/DL configuration; configure the UE to transmit the additional DMRS at one or more symbol locations in the special slots if indicated by the configuration information; configure the UE to transmit the DMRS at the PUSCH DM-RS positions in the uplink slots; and configure the UE to transmit the PUSCH within the uplink slots.

2. The apparatus of claim 1, wherein the processing circuitry is further configured to: determine whether transmission of the additional DMRS at the symbol locations in the special slots conflict with a uplink transmission; and configure the UE to either refrain from transmission of the additional DMRS at the symbol locations in the special slots or refrain from transmission of a least a portion of the uplink transmission in response to determination of a conflict.

3. The apparatus of claim 2, wherein the symbol locations m the special slots for transmission of the additional DMRS comprise a single last symbol of a special slot when single symbol DMRS is configured for transmission of the PUSCH, and wherein the symbol locations in the special slots for transmission of the additional DMRS comprise two last symbols of the special slot when double symbol DMRS is configured for transmission of the PUSCH.

4. The apparatus of claim 2 wherein the processing circuitry' is configured to cause the UE to refrain from transmission of the additional DMRS at the symbol locations in the special slots unless the UE is configured for PUSCH repetition.

5. The apparatus of claim 4 wherein the processing circuitry is configured to cause the UE to refrain from transmission of the additional DMRS at the symbol locations in the special slots unless the UE is configured for PUSCH repetition with a number of repetitions less than a configured value.

6. The apparatus of claim 2, wherein when transmission of the additional DMRS at the symbol locations in the special slots conflict with a physical uplink control channel (PUCCH) carrying uplink control information (UCI), the processing circuitry is configured to: drop the PUCCH, and multiplex the UCI on the PUSCH in the uplink slot, wherein the UE is configured to transmit the additional DMRS at one or more symbol locations in the special slots.

7. The apparatus of claim 2, wherein when transmission of the additional DMRS at the symbol locations in the special slots conflict with a physical uplink control channel (PUCCH) carrying uplink control information (UCI) that include HARQ/ACK feedback, the processing circuitry is to configure the UE to: refrain from transmission of the additional DMRS at one or more symbol locations in the special slots, and transmit the PUCCH carrying the UCI as scheduled.

8. The apparatus of claim 2, wherein the configuration information to indicate if the additional DMRS are to be transmitted in the special slots comprises dedicated radio-resource control (RRC) signalling, and wherein the processing circuitry is to decode the RRC signalling to determine the symbol locations of additional DMRS in the special slots.

9. The apparatus of claim 2, wherein the configuration information to indicate if the additional DMRS are to be transmitted in the special slots is dynamically indicated in a DCI format.

10. The apparatus of claim 2, wherein the configuration information to indicate if the additional DMRS are to be transmitted in the special slots comprises one or more additional bits in antenna port configuration information in a downlink control information (DCI) format.

1 1 . The apparatus of claim 2, wherein the special slots have an uplink part comprising one or more symbol locations for transmission of uplink symbols, and wherein the symbol locations for transmission of the additional DMRS are within the uplink part of the special slots.

12. The apparatus of claim 2, wherein the processing circuitry is to configure the UE to use a DMRS configuration for the uplink slot for transmission of the additional DMRS in the special slot.

13. The apparatus of claim 12, wherein the processing circuitry' is to determine the PUSCH DM-RS positions within the uplink slots for transmission of the DM RS based on one or more of: a duration of the PUSCH; additional positions for the DMRS configured by higher layer parameter “ dmr s- Additi onalPositi on” ; whether mapping type A or type B is used for transmission of the PUSCH transmission; whether single symbol or double symbol DMRS is used for transmission of the PUSCH; and whether frequency hopping is employed for transmission of the PUSCH.

14. The apparatus of claim 1, wherein the memory' is configured to store the configuration information, and wherein the processing circuitry comprises a baseband processor.

15. A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE) configured for operation in a fifth-generation (5G) new radio (NR) network, wherein for unpaired spectrum operation, the UE is configured with a semi-static uplink/downlink (UL/DL) configuration comprising a plurality of slots including uplink slots, downlink slots and special slots, wherein at least some of the special slots precede the uplink slots, wherein the processing circuitry is configured to: determine PUSCH DM-RS positions within the uplink slots for transmission of a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH); decode configuration information received from a generation Node B (gNB) to indicate if additional DMRS are to be transmitted in the special slots that precede the uplink slots of the UL/DL configuration, configure the UE to transmit the additional DMRS at one or more symbol locations in the special slots if indicated by the configuration information; configure the UE to transmit the DMRS at the PUSCH DM-RS positions in the uplink slots; and configure the UE to transmit the PUSCH within the uplink slots.

16. The non-transitory' computer-readable storage medium of claim 15, wherein the processing circuitry? is further configured to: determine whether transmission of the additional DMRS at the symbol locations in the special slots conflict with a uplink transmission; and configure the UE to either refrain from transmission of the additional DMRS at the symbol locations in the special slots or refrain from transmission of a least a portion of the uplink transmission m response to determination of a conflict.

17. The non-transitory computer-readable storage medium of claim 16, wherein the symbol locations in the special slots for transmission of the additional DMRS comprise a single last symbol of a special slot when single symbol DMRS is configured for transmission of the PUSCH, and wherein the symbol locations in the special slots for transmission of the additional DMRS comprise two last symbols of the special slot when double symbol DMRS is configured for transmission of the PUSCH.

18. The non-transitory computer-readable storage medium of claim 17 wherein the processing circuitry is configured to cause the UE to refrain from transmission of the additional DMRS at the symbol locations in the special slots unless the UE is configured for PUSCH repetition with a number of repetitions less than a configured value.

19. An apparatus for a generation Node b (gNB) configured for operation in a fifth-generation (5G) new radio (NR) network, the apparatus comprising: processing circuitry; and memory, wherein for unpaired spectrum operation, the gNB is to configure a user equipment (UE) with a semi-static uplink/downlink (UL/DL) configuration comprising a plurality of slots including uplink slots, downlink slots and special slots, wherein at least some of the special slots precede the uplink slots, wherein the processing circuitry is configured to: determine PUSCH DM-RS positions within the uplink slots for reception of a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH); encode configuration information for transmission to a UE to indicate if additional DMRS are to be transmitted by the UE in the special slots that precede the uplink slots of the UL/DL configuration; decode the additional DMRS, received from the UE, at one or more symbol locations in the special slots if indicated by the configuration information, decode the DMRS, received from the UE, at the PUSCH DM-RS positions in the uplink slots; and decode the PUSCH, received from the UE, within the uplink slots based on the additional DMRS received from the UE in the special slots and the DMRS received from the UE at the PUSCH DM-RS positions in the uplink slots.

20. The apparatus of claim 19, wherein the configuration information to indicate if the additional DMRS are to be transmitted in the special slots comprises one or more additional bits in antenna port configuration information in a downlink control information (DCI) format.