Demodulation reference signal transmission from multiple base stations

Abstract

Systems, apparatus, methods, and computer-readable media for user equipment (UE) idle mode operation are provided. In an embodiment, the UE wakes up more than once during a discontinuous reception (DRX) cycle. Inter-frequency measurement requirements may be relaxed based on the DRX cycle length. Some embodiments include RF circuit warm-up overhead reduction by on-duration separation with radio frequency (RF) circuit switching mode adaptation. Some embodiments include RF circuit warm-up overhead reduction by adaptive synchronization signal block (SSB) reference symbol down selection. Other embodiments are also described and / or protection is claimed.

Description

[0001] Related patent applications

[0002] This patent application claims priority to U.S. Provisional Patent Application No. 62 / 739,052 filed on September 28, 2018, the contents of which are hereby incorporated by reference in their entirety. Technical Field

[0003] Various embodiments of the present patent application relate generally to the field of wireless communications, and in particular to multiple transmission / reception points (TRPs) and / or coordinated multi-point communications. Background Art

[0004] The New Radio (NR) Demodulation Reference Signal (DM-RS) is a user-specific reference signal that can be used for channel estimation for downlink shared channel (PDSCH) and uplink shared channel (PUSCH) data demodulation. The receiver (e.g., UE 101 or RAN node 111) uses DMRS to estimate the radio channel for demodulating the corresponding physical channel. In Rel-15 NR, a Gold sequence of length 31 is used to generate DM-RS. There are two different DM-RS configurations, namely configuration type 1 and type 2. Type 1 DM-RS has 2 code division multiplexing (CDM) port groups, where each group occupies 6 orthogonal frequency resource elements (REs) within a physical resource block (PRB) on a single OFDM symbol. Type 1 single symbol DM-RS can support up to 4 orthogonal DM-RS ports, where 2 DM-RS ports are multiplexed within each CDM group using a frequency domain orthogonal cover code (FD-OCC). Type 2 DM-RS has 3 CDM port groups, each of which occupies 4 orthogonal REs within a PRB on a single OFDM symbol. Type 2 single symbol DM-RS can support up to 6 orthogonal DMRS ports, with each CDM group having 2 DM-RS ports multiplexed using FD-OCC. In addition, in addition to FD-OCC, both type 1 and type 2 DM-RS can occupy two OFDM symbols with ports multiplexed using time domain (TD) OCC. Dual symbol type 1 DM-RS can support up to 8 ports, with 4 ports in each CDM group. Dual symbol type 2 DM-RS can support up to 12 orthogonal ports, with 4 ports in each CDM group. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 The architecture of a system of networks according to some embodiments is shown. Figure 2 Different types of demodulation reference signals (DM-RS) for 5G / NR implementations are shown. Figure 3Various examples of multiple transmission reception points (TRPs) and multiple downlink control information (DCI) operations are shown. Figure 4 Examples of infrastructure equipment according to various embodiments are shown. Figure 5 An example of a communication circuit that can be used to practice the embodiments discussed herein is shown. Fig. 6A , Figure 6B and Figure 7 Example procedures for practicing the various embodiments discussed herein are shown. DETAILED DESCRIPTION

[0006] The embodiments discussed herein provide techniques for transmitting and receiving demodulation reference signals (DMRS) from multiple transmission / reception points (TRPs). Multiple TRPs transmitting / receiving DMRS can be connected by ideal or non-ideal backhaul links with different degrees of coordination between TRPs. In some embodiments, DMRS ports can be subdivided into DMRS port groups that can correspond to a single or multiple TRPs. The embodiments herein include DMRS transmission (Tx) and reception (Rx) techniques based on a single downlink control information (DCI) or multiple DCI configurations for multiple TRPs. Other embodiments are also described and / or protection is claimed.

[0007] See now Figure 1 , wherein an exemplary architecture of a system 100 of a network according to various embodiments is shown. The following description is provided for an exemplary system 100 operating in conjunction with a fifth generation (5G) or new radio (NR) system standard or a long term evolution (LTE) system standard as provided by the third generation partnership project (3GPP) technical specifications. However, the exemplary embodiments are not limited in this regard, and the embodiments may be applied to other networks that benefit from the principles described herein, such as future 3GPP systems (e.g., sixth generation (6G)) systems, IEEE 802.16 protocols (e.g., wireless metropolitan area networks (WMANs), world-wide interoperability for microwave access (WiMAX)), etc.), etc.

[0008] like Figure 1As shown, system 100 includes user equipment (UE) 101a and UE 101b (collectively referred to as "multiple UE 101" or "UE 101"). UE 101 is any device with radio communication capabilities (such as a wireless communication interface) and describes a remote user of network resources in a communication network. In this example, UE 101 is shown as a smart phone, but may also include any mobile or non-mobile computing device, such as a consumer tablet, wearable device, desktop computer, laptop computer, in-vehicle infotainment (IVI) device, head-up display (HUD) device, Internet of Things (IoT) device, embedded system or microcontroller, networking or "smart" device, etc. UE 101 includes various hardware elements, such as baseband circuits, memory circuits, radio frequency (RF) circuits, and interface circuits (e.g., input / output (I / O) interfaces), some or all of which may be coupled to each other via suitable interconnect (IX) technology. The RF circuit includes various hardware elements (e.g., switches, filters, amplifiers, digital signal processors (DSPs), etc.) that are configured to use electromagnetic radiation modulated by a non-solid medium to achieve communication with a wireless network. The electronic components may be arranged to receive a signal path (or receive (Rx) RF chain) to down-convert the received RF signal and provide the baseband signal to the baseband circuit, and may be arranged to transmit a signal path to up-convert the baseband signal provided by the baseband circuit and provide the RF output signal to the antenna array via the front-end module for transmission. The baseband circuit and the RF circuit allow the UE 101 to be connected or communicatively coupled to the radio access network (RAN) 110. In various embodiments, the UE 101 may have multiple panels or multiple antenna arrays and be configured to receive multiple independently scheduled data streams from different TRPs 111 in a multi-TRP / panel transmission based on multiple DCIs. These aspects will be discussed in more detail below.

[0009] UE 101b is shown as being configured to access access point (AP) 106 via connection 107. Connection 107 may include a wireless local area network (WLAN) connection conforming to any IEEE 802.11 protocol, where AP 106 may be a wireless local area network (WLAN) connection. Routers, gateway devices, etc. In this example, AP 106 is shown connected to the Internet without being connected to the core network of the wireless system (described in further detail below). In various embodiments, UE 101b, RAN 110 and AP 106 can be configured to utilize LTE-WLAN aggregation (LWA) operation and / or LTE / WLAN radio level operation integrated with IPsec tunnel (LWIP).

[0010] RAN 110 is a set of RAN nodes 111 that implement a radio access technology (RAT); as used herein, the term "RAT" refers to a type of technology used for radio access, such as NR, E-UTRA, WiFi / WLAN, etc. A set of RAN nodes 111 in RAN 110 are connected to each other via interface 112 and to CN 120 through interface 113. In an embodiment, when system 100 is a UTRAN or GERAN system, RAN 110 can be a universal terrestrial radio access network (UTRAN) or a mobile expert group (GSM) / enhanced data rate for GSM (EDGE) RAN (GERAN), when system 100 is an LTE or 4G system, RAN can be an evolved UTRAN (E-UTRAN), or when system 100 is a NR / 5G system, RAN can be a next generation (NG) RAN or 5G RAN. UE 101 utilizes connections (or channels) 103 and 104, respectively, each connection including a physical communication interface or layer. As used herein, the term "channel" or "link" refers to any tangible or intangible transmission medium for transmitting data or data streams. In addition, as used herein, the term "link" refers to a connection between two devices for transmitting and receiving information through a RAT. Figure 1 , connections 103 and 104 are shown as air interfaces to achieve communication coupling and may conform to cellular communication protocols such as GSM, code division multiple access (CDMA), push-to-talk (PTT) and / or PPT over cellular (POC), UMTS, LTE, 5G / NR, etc. UE 101 may also directly exchange data via a proximity service (ProSe) or sidelink (SL) interface 105 including one or more physical and / or logical SL channels.

[0011] The RAN 110 includes one or more RAN nodes 111a and 111b (collectively referred to as "multiple RAN nodes 111" or "RAN node 111") that enable connections 103 and 104. The RAN node 111 is an infrastructure equipment that provides radio baseband functions for data and / or voice connectivity between a network (e.g., core network (CN) 120) and one or more users (e.g., UE 101). The RAN node 111 may be referred to as a node B 111 in a UMTS system, an evolved node B (eNB) 111 in an LTE system, a next-generation node B (gNB) 111 or a next-generation eNB (ng-eNB) in a 5G / NR system, a road side unit (RSU) specifically implemented by vehicle-to-everything (V2X), and the like. In some embodiments, each RAN node 111 may be a transmission / reception point (TRP). In other embodiments, each RAN node 111 may have multiple antenna elements, each of which may be a separate TRP.

[0012] The RAN nodes 111 may include ground stations (e.g., terrestrial access points) or satellite stations that provide coverage within a geographic area (e.g., a cell). The RAN nodes 111 may be implemented as one or more dedicated physical devices such as macrocell base stations and / or low-power base stations for providing femtocells, picocells, or other similar cells with smaller coverage areas, smaller user capacities, or higher bandwidths than macrocells. Any of the RAN nodes 111 may serve as an endpoint for an air interface protocol and may be the first point of contact for the UE 101. In some embodiments, any of the RAN nodes 111 may perform various logical functions of the RAN 110, including but not limited to the functions of a radio network controller (RNC), such as radio bearer management, uplink and downlink dynamic radio resource management, data packet scheduling, and mobility management.

[0013] In some embodiments, all or part of the RAN node 111 may be implemented as one or more software entities running on a server computer as part of a virtual network (e.g., cloud RAN (CRAN), virtual baseband unit pool (vBBUP), etc.). In these embodiments, the RAN node 111 may implement RAN functional splitting, where different protocol entities are operated by different elements. The term "element" as used herein refers to a unit that is indivisible at a given level of abstraction and has clearly defined boundaries. One or more RAN nodes 111 may represent a RAN node 111 connected to a network via a corresponding FI interface ( Figure 1 In some implementations, the gNB-DU may include one or more remote radio heads or RFEMs, and the gNB-CU may be operated by a server (not shown) located in the RAN 110 or by a pool of servers in a manner similar to CRAN / vBBUP.

[0014] The RAN nodes 111 may be configured to communicate with each other via interfaces 112. The interfaces 112 may include a user plane interface for carrying user plane data between the RAN nodes 111, and a control plane interface for carrying control signaling between the RAN nodes 111. When the system 100 is an LTE system, the interface 112 may be an X2 interface 112, and when the system 100 is a 5G / NR system, the interface 112 may be an Xn interface 112. In some embodiments, the interface 112 may be a wireless backhaul connection.

[0015] According to various embodiments, the RAN node 111 supports multi-TRP transmission based on a single DCI and / or multi-TRP transmission scheme based on multiple DCI. Multi-TRP transmission based on a single DCI involves one TRP in a TRP transmitting a DCI on a corresponding PDCCH, which schedules a PDSCH to be transmitted by / from some or all TRPs, and each PDSCH is sent from a separate TRP. Multi-TRP transmission based on multiple DCI involves transmitting multiple DCIs on a corresponding PDCCH to schedule corresponding PDSCHs, and each PDSCH is sent from a separate TRP. Multi-TRP transmission based on multiple DCIs may be used when the TRPs / RAN nodes 111 are interconnected by non-ideal backhaul, since joint scheduling may not be feasible due to delays in data / CSI exchange between TRPs. In these embodiments, the UE 101 is able to receive multiple independently scheduled data streams from different TRPs in a multi-TRP / panel transmission based on multiple DCIs.

[0016] In an embodiment, UE 101 may be configured to communicate with each other or with any of RAN nodes 111 on a multi-carrier communication channel using orthogonal frequency division multiplexing (OFDM) communication signals according to various communication techniques, such as but not limited to OFDMA communication techniques (e.g., for DL ​​communication) or single carrier frequency division multiple access (SC-FDMA) communication techniques (e.g., for UL and ProSe / SL communication), although the scope of the embodiments is not limited in this respect. OFDM signals may include multiple orthogonal subcarriers.

[0017] DL transmissions and UL transmissions may be organized into frames having a duration of 10 ms, where each frame includes ten 1 ms subframes and each subframe includes an integer number of time slots. A time-frequency radio resource grid may be used to indicate the physical resources in the DL or UL in the corresponding time slot. Each column and each row of the DL resource grid corresponds to an OFDM symbol and an OFDM subcarrier, respectively, and each column and each row of the UL resource grid corresponds to an SC-FDMA symbol and an SC-FDMA subcarrier, respectively. There is one resource grid for a given antenna port p, a subcarrier spacing (SCS) configuration μ, and a transmission direction (DL or UL). The frequency position of a subcarrier refers to the center frequency of that subcarrier. Each element in the resource grid for antenna port p and SCS configuration μ is called a resource element (RE) and is represented by (k, l) p,μ uniquely identifies, where k is an index in the frequency domain (e.g., k is a subcarrier index relative to a reference or reference point), and l refers to a symbol position in the time domain relative to a certain reference point (e.g., l is an OFDM symbol index relative to a reference or reference point). RE(k,l) p,μ Corresponding to physical resources and complex values In other words, The value of RE(k,l) for antenna port p and SCS configuration μ. The set of REs constitutes a resource block (RB), which is usually defined as = 12 consecutive subcarriers in the frequency domain.

[0018] The antenna ports are defined so that the channel on which a symbol on the antenna port is transmitted can be inferred from the channel on which another symbol on the same antenna port is transmitted. Two antenna ports are said to be quasi co-located (QCLed) if large-scale properties of the channel on which a symbol on one antenna port is transmitted can be inferred from the channel on which a symbol on another antenna port is transmitted. Large-scale properties include one or more of delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial Rx parameters.

[0019] For DM-RS associated with PDSCH, the channel on which a PDSCH symbol on one antenna port is transmitted can be inferred from the channel on which a DM-RS symbol on the same antenna port is transmitted only if both symbols are within the same resources as the scheduled PDSCH, in the same time slot, and in the same precoding RB group (PRG), as described in clause 5.1.2.3 of 3GPP TS 38.214 v15.2.0 (2018-06). For DM-RS associated with PDCCH, the channel on which a PDCCH symbol on one antenna port is transmitted can be inferred from the channel on which a DM-RS symbol on the same antenna port is transmitted only if both symbols are within the same resources as the scheduled PDSCH, in the same time slot, and in the same precoding RB group (PRG), as described in clause 7.3.2.2 of 38.211 v15.3.0 (2018-09). For DM-RS associated with PBCH, the channel on which a PBCH symbol on one antenna port is transmitted can be inferred from the channel on which a DM-RS symbol on the same antenna port is transmitted only when both symbols are within an SS / PBCH block transmitted in the same time slot and have the same block index according to clause 7.4.3.1, as described in clause 7.3.2.2 of 38.211v15.3.0(2018-09).

[0020] The bandwidth part (BWP) is the given parameter μ in BWP i for a given carrier. iA subset of contiguous common RBs. The UE 101 may be configured to have up to four BWPs in the DL, with a single downlink BWP being active at a given time. The UE 101 is not expected to receive PDSCH, PDCCH, or CSI-RS (except RRM) outside of the active BWP. The UE 101 may be configured to have up to four BWPs in the UL, with a single UL BWP being active at a given time. The UE 101 does not transmit PUSCH or PUCCH outside of the active BWP. For active cells, the UE 101 does not transmit SRS outside of the active BWP.

[0021] There are several different physical channels and physical signals transmitted using RBs, physical RBs (PRBs) and / or separate REs. A physical channel corresponds to a set of REs that carry information from higher layers. Physical channels include physical UL channels (e.g., physical UL shared channel (PUSCH), physical UL control channel (PUCCH), physical random access channel (PRACH), etc.) and physical DL channels (e.g., physical DL shared channel (PDSCH), physical DL control channel (PDCCH), physical broadcast channel (PBCH), etc.). Physical signals are used by the physical layer (PHY) but do not carry information from higher layers. Physical signals include physical UL signals (e.g., demodulation reference signal (DMRS or DM-RS), phase tracking reference signal (PTRS), sounding reference signal (SRS), etc.) and physical DL signals (e.g., DMRS, PTRS, channel state information reference signal (CSI-RS), primary synchronization signal (PSS), secondary synchronization signal (SSS), etc.).

[0022] The PDSCH carries user data and high-layer signaling to the UE 101, and the PDCCH carries DL resource allocation information for receiving the PDSCH. Each UE 101 monitors a PDCCH candidate set on one or more activated serving cells as configured by high-layer signaling for control information (e.g., downlink control information (DCI)), where monitoring means attempting to decode the PDCCH candidate set according to one or more monitored DCI formats (e.g., DCI formats 0 to 6-2, as discussed in Section 5.3.3 of 3GPP TS 38.212v15.3.0 (2018-09) (hereinafter "TS 38.212v15.3.0"), DCI formats 0_0 to 2_3, as discussed in Section 7.3 of TS 38.212v15.3.0, etc.). The DCI includes, among other things, DL allocations and / or UL scheduling grants, including, for example, modulation and coding formats, resource allocations, and HARQ information, as well as other information / commands. Each UE 101 monitors (or attempts to decode) a corresponding group of PDCCH candidates at one or more configured monitoring occasions according to a UE or cell-specific search space (for LTE / 4G), or monitors (or attempts to decode) a corresponding group of PDCCH candidates at one or more configured monitoring occasions in one or more configured control resource sets (CORESETs) according to a corresponding search space configuration (for NR / 5G). A CORESET includes a set of PRBs with a duration of 1 to 3 OFDM symbols. REGs and CCEs are defined in a CORESET, where each CCE includes a set of REGs. Interleaved and non-interleaved CCE to REG mappings are supported in a CORESET. Each REG that carries a PDCCH carries its own DMRS.

[0023] PDSCH transmission is scheduled by DCI format 1_0 and DCI format 1_1. DCI format 1_0 is used to schedule PDSCH in one DL cell, and DCI format 1_1 is used to schedule PDSCH in one cell. DCI format 1_0 includes, among others, frequency domain resource allocation, time domain resource allocation, and other fields / elements as discussed in TS 38.212 v15.3.0. DCI format 1_1 includes, among others, bandwidth part indicator, frequency domain resource allocation, time domain resource allocation, antenna ports, where the number of CDM groups without data of values ​​1, 2, and 3 refers to CDM groups {0}, {0,1}, and {0,1,2}, respectively, and antenna ports {p0,..,p v-1} Determined according to the ordering of DMRS ports given by Table 7.3.1.2.2-1 / 2 / 3 / 4 of TS 38.212v15.3.0 and other fields / elements discussed in TS 38.212v15.3.0.

[0024] RAN 110 is shown as being communicatively coupled to a core network (CN) 120, which includes one or more network elements 122 configured to provide various data and telecommunication services to customers / users (e.g., users of UE 101) connected to CN 120 via RAN 110. The term "network element" as used herein refers to a physical or virtualized device and / or infrastructure for providing wired or wireless communication network services, and may be considered synonymous with and / or referred to as a networked computer, networking hardware, network equipment, network node, router, switch, hub, bridge, radio network controller (RNC), RAN equipment, RAN node, gateway, server, cloud node, virtualized network function (VNF), NFV infrastructure (NFVI), etc. Network element 122 may be one or more server computer systems that may implement various CN elements (e.g., network functions (NF) and / or application functions (AF)), such as those discussed herein. The components of CN120 can be implemented in one physical node or in separate physical nodes, including components for reading and executing instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium). In some embodiments, network function virtualization (NFV) can be used to virtualize any or all network node functions (described in further detail below) via executable instructions stored in one or more computer-readable storage media. A logical instance of CN120 may be referred to as a network slice, and a logical instance of a portion of CN 120 may be referred to as a network sub-slice. As used herein, the term "instantiate / instantiation" and the like refer to the creation of an instance, and "instance" refers to the specific appearance of an object, which may occur, for example, during the execution of a program code. The NFV architecture and infrastructure can be used to virtualize one or more network functions onto physical resources comprising a combination of industry-standard server hardware, storage hardware, or switches (alternatively performed by proprietary hardware). In other words, the NFV system can be used to perform a virtual or reconfigurable implementation of one or more NF / AFs.

[0025] In embodiments where CN 120 is an evolved packet core (EPC) in an LTE system, one or more network elements 122 may include or operate one or more mobility management entities (MMEs), serving gateways (S-GWs), PDN gateways (P-GWs), home subscriber servers (HSSs), policy control and charging rules functions (PCRFs), and / or other similar LTE CN elements. In these embodiments, E-UTRAN 110 may be connected to EPC 120 via an S1 interface 113. In these embodiments, S1 interface 113 may be divided into two parts: an S1-U interface 114, which carries traffic data between RAN node 111 and S-GW; and an S1-MME interface 115, which is a signaling interface between RAN node 111 and MME. In addition, the P-GW within EPC 120 may route data packets between EPC 120 and external networks such as networks including packet data networks (PDNs) 130 via an Internet Protocol (IP) interface 125. The PDN 130 may be an operator-external public or private PDN (eg, an enterprise network, a cloud computing service, etc.) or an operator-internal PDN (eg, for providing IMS and / or IP-CAN services).

[0026] In an embodiment where the CN 120 is a 5GC 120, the network element 122 may implement one or more instances of an authentication server function (AUSF), an access and mobility management function (AMF), a session management function (SMF), a network exposure function (NEF), a policy control function (PCF), a NF repository function (NRF), a unified data management (UDM) entity, an AF, a user plane function (UPF), a short message service function (SMSF), a non-3GPP interworking function (N3IWF), a network slice selection function (NSSF), and / or other similar NR NFs. In such embodiments, the NG-RAN 110 may be connected to the 5GC 120 via an NG interface 113. In these embodiments, the NG interface 113 may be divided into two parts: an NG-U interface 114, which carries traffic data between the RAN node 111 and the UPF; and an NG-C interface 115, which is a signaling interface between the RAN node 111 and the AMF. In addition, the UPF within the 5GC 120 can perform packet routing, filtering, inspection, forwarding, etc. between the 5GC 120 and an external network such as a data network (DN) 130 via the IP interface 125. The DN 130 may represent one or more DNs including one or more local area DNs (LADNs), and may be an operator-external public, private PDN, or an operator-internal PDN, as described above.

[0027] The CN 120 is shown to be communicatively coupled to the PDN / DN 130 via an IP communication interface 125. The PDN / DN 130 may include one or more application servers (AS). The application server (and network element 122) includes one or more physical and / or virtualized systems for providing functions (or services) to one or more clients (e.g., UE 101) via a network. Such servers may include various computer devices having rack computing architecture components, tower computing architecture components, blade computing architecture components, etc. The server may represent a server cluster, a server group, a cloud computing service, or other groupings or pools of servers that may be located in one or more data centers. The server may also be connected to one or more data storage devices (not shown) or otherwise associated with one or more data storage devices. In general, the AS 130 provides applications or services that use IP / network resources. As an example, the server may provide traffic management services, cloud computing services, content streaming services, immersive gaming experiences, social networking and / or microblogging services, one or more communication services (e.g., VoIP sessions, PTT sessions, group communication sessions, social networking services, etc.), and / or other similar services to the UE 101 via the CN 120.

[0028] Figure 2 Different types of DM-RS for NR implementation are shown. A receiver (e.g., UE 101 for DL ​​transmission or RAN node 111 for UL transmission) uses DM-RS to estimate a radio channel for demodulating a corresponding physical channel. For example, UE 101 may use DM-RS for channel estimation for PDSCH data demodulation and PUSCH data demodulation. In NR, a front-loaded DM-RS structure is used as a baseline to achieve low-latency decoding. In a time-frequency resource grid, the front-loaded DM-RS may be located just after the control region, followed by the data region. Once the channel is estimated based on the front-loaded DM-RS, the receiver can coherently demodulate the data in the data region. The term "front-loaded" refers to the first appearance of DMRS in a scheduled time slot. Additional DM-RS opportunities / symbols may be present in (or configured for) the latter part of the time slot, which can be used to support high-speed (high mobility) scenarios. Various DMRS modes for data demodulation are supported, wherein at least one configuration supports a front-loaded DMRS mode mapped on 1 or 2 adjacent OFDM symbols. In some embodiments, the DMRS type and configuration of the front-loaded DMRS and the additional DMRS are the same.In addition, the DMRS configuration and the positioning / location of the corresponding DMRS in the time slot also depends on the PDSCH / PUSCH mapping type A or B (see, for example, TS 38.211 v15.3.0).

[0029] NR defines two time-domain PDSCH mapping types that differ in the position of the first DM-RS symbol: PDSCH mapping type A and PDSCH mapping type B. In mapping type A, the first DM-RS is located in the second symbol or the third symbol of the slot, and the DM-RS is mapped relative to the start of the slot boundary. The first DM-RS timing is located in the second symbol or the third symbol in the DL slot because the CORESET is located at the beginning of the slot. In mapping type B, the first DM-RS is located in the first symbol of the data allocation. In mapping type B, the DM-RS position is not given relative to the slot boundary, but relative to where the data is located.

[0030] DM-RS may be configured to each UE 101 using a dynamic mechanism (e.g., DCI-based configuration), a semi-static mechanism (e.g., RRC-based configuration), or a combination thereof. For example, the mapping type for PDSCH is typically signaled dynamically using DCI, while the mapping type for PUSCH is typically configured semi-statically using RRC. In another example, the DM-RS configuration type, the maximum number of front-loaded DMRS symbols (e.g., 1 or 2), and the additional DM-RS positions are semi-statically configured by RRC parameters; and the actual number of front-loaded symbols, the allocated DMRS ports, and the potential presence of other ports in the unallocated CDM group are dynamically indicated using DCI (see, e.g., TS 38.212 v15.3.0).

[0031] Different DM-RS patterns separated in time domain, frequency domain and code domain can be configured. DM-RS has two configuration types, including configuration type 1 and configuration type 2, which differ in frequency domain mapping and the maximum number of orthogonal reference signals (RS). Different configuration types are used to map PDSCH DM-RS to physical resources in different ways, and UE 101 determines from the RRC parameter dmrs-Type. DM-RS configuration type 1 can provide up to four orthogonal RSs using a single symbol DM-RS and up to eight orthogonal RSs using two symbols (or "double symbols") DM-RS, while DM-RS configuration type 2 can provide 6 and 12 orthogonal RSs depending on the number of symbols. Different PDSCH mapping types can be combined with different RS types. Both DM-RS configuration type 1 and DM-RS configuration type 2 can occupy two OFDM symbols with ports multiplexed using time domain (TD) OCC (TD-OCC) and frequency domain (FD) OCC (FD-OCC).

[0032] 3GPP NR supports multiple stream transmission, which allows a single UE 101 or TRP to transmit (or be scheduled to transmit) multiple streams (or multiple layers), or multiple UEs 101 or TRPs can transmit (or be scheduled to transmit) multiple streams simultaneously according to channel conditions. In order to support multi-stream (multi-layer) multiple-input multiple-output (MIMO) transmission, multiple orthogonal DMRS sequences are used, and each stream / layer uses a DMRS sequence. This is achieved by allocating a single antenna port to the demodulation of each stream / layer. Because the DMRS of a stream is decoded independently from other DMRSs of other streams for channel estimation of the stream, the DMRS sequences must be separated orthogonally to avoid interference. Orthogonality is achieved by frequency division multiplexing (FDM) (e.g., comb structure), time division multiplexing (TDM) and / or code division multiplexing (CDM) (e.g., cyclic shift with a base sequence or orthogonal cover code (OCC)). Different orthogonal DMRS sequences (each sequence corresponds to an antenna port) share the same time-frequency resources in a CDM group. Single-user (SU)-MIMO supports at least 8 orthogonal DL DMRS ports, and multi-user (MU)-MIMO supports a maximum of 12 orthogonal DL DMRS ports.

[0033] Each CDM group includes DM-RS ports mapped to REs as a group. Figure 2 , which are shown as differently shaded REs in the figure. The DM-RS ports in the same CDM group are multiplexed using the same resources and using OCC. For example, FD-OCC is used to multiplex two DMRS ports together into a pair of symbols, so each pair of REs in the two symbol DM-RS configuration uses an OCC of length 2. In addition, TD-OCC can be used to extend the multiplexing capacity of the CDM group to four ports. This means that in Figure 2 In each shadow RE in , there may be four ports. In other words, for DM-RS configuration type 1, a total of four DM-RS ports may be multiplexed into one symbol, and a total of eight DM-RS ports may be multiplexed into two symbols. The DMRS ports and their association with the OCC and CDM groups of the DL DMRS are shown in Tables 1 and 2 below (see, for example, Tables 7.4.1.1.2-1 and 7.4.1.1.2-2 in 3GPP TS38.211v15.3.0 (2018-09) (hereinafter referred to as "TS 38.211v15.3.0")).

[0034] DM-RS configuration type 1 has two CDM port groups, where each group occupies six orthogonal frequency REs within a PRB on a single OFDM symbol. DM-RS configuration type 1 uses a comb 2 structure with two CDM groups, and each pair of alternating REs in each CDM group is an FD-OCC of length 2. Since DM-RS configuration type 1 has two CDM port groups, a single symbol DM-RS configuration type 1 is able to multiplex four DMRS ports, with two DMRS ports per CDM group. A single symbol DM-RS configuration type 1 can support up to four orthogonal DM-RS ports, with two DM-RS ports multiplexed within each CDM group using FD-OCC. For a single symbol DM-RS configuration type 1, each CDM group supports two orthogonally multiplexed DM-RS ports or MIMO layers (e.g., a single symbol DM-RS configuration type 1 supports a total of four orthogonal DM-RS ports). Double S symbol DM-RS configuration type 1 can support up to eight ports, with four ports in each CDM group. For dual-symbol DM-RS configuration type 1, additional multiplexing of DMRS ports in TD is achieved using a time domain OCC of length 2. In this case, each CDM group includes FD-OCC and TD-OCC multiplexing and supports four orthogonal DM-RS ports (e.g., a total of eight orthogonal DM-RS ports are supported).

[0035] DM-RS configuration type 2 has three CDM port groups, where each group occupies six orthogonal REs within a PRB on a single OFDM symbol. DM-RS configuration type 2 uses a comb 3 structure with three CDM groups, and each pair of adjacent REs in each CDM group is an FD-OCC of length 2. A single symbol DM-RS configuration type 2 can support up to 6 orthogonal DMRS ports, where each CDM group has two DM-RS ports multiplexed using FD-OCC. For a single symbol DM-RS configuration type 2, each CDM group supports two orthogonal DMRS ports, and a total of 6 orthogonal DMRS ports are supported. Two symbol DM-RS configuration type 2 can support up to twelve orthogonal ports, with four ports in each CDM group. For two symbol DM-RS configuration type 2, TD-OCC is used to multiplex a total of four ports in each CDM group and a total of twelve orthogonal DMRS ports across three CDM groups.

[0036] When receiving a PDSCH scheduled by DCI format 1_0 or receiving a PDSCH prior to a dedicated higher layer configuration of any of the parameters dmrs-AdditionalPosition, maxLength, and dmrs-Type, UE 101 assumes that PDSCH is not present in any symbol carrying DM-RS, except for PDSCH with an allocated duration of 2 symbols of PDSCH mapping type B (e.g., as described in subclause 7.4.1.1.2 of TS 38.211v15.3.0), and a front-loaded single symbol DM-RS configuration type 1 on transmission DM-RS port 1000, and all remaining orthogonal antenna ports are not associated with the transmission of PDSCH to another UE 101. Additionally or alternatively, for PDSCH with mapping type A, UE 101 assumes that dmrs-AdditionalPosition = "pos2 (position 2)" and that up to two additional single symbol DM-RSs (e.g., single symbol DM-RS configuration type 1) are present in the timeslot according to the PDSCH duration indicated in the DCI, as defined in subclause 7.4.1.1 of TS 38.211v15.3.0. Additionally or alternatively, for PDSCH with an allocation duration of 7 symbols for a normal CP or 6 symbols for an extended CP with mapping type B, when the current loaded DM-RS symbol is located in the 1st or 2nd symbol of the PDSCH allocation duration, respectively, UE 101 assumes that there is one additional single symbol DM-RS (e.g., single symbol DM-RS configuration type 1) in the 5th or 6th symbol, otherwise UE 101 assumes that there are no additional DM-RS symbols. Additionally or alternatively, for a PDSCH with an allocation duration of 4 symbols of mapping type B, UE 101 assumes that no additional DM-RS is present. Additionally or alternatively, for a PDSCH with an allocation duration of 2 symbols of mapping type B, UE 101 assumes that no additional DM-RS is present, and UE 101 assumes that PDSCH is present in symbols carrying DM-RS.

[0037] When receiving a PDSCH scheduled by DCI format 1_1 via a PDCCH with a CRC scrambled by a C-RNTI, MCS-C-RNTI, or CS-RNTI, the UE 101 may be configured with a higher-level parameter dmrs-Type, and the configured DM-RS configuration type is used to receive the PDSCH defined in subclause 7.4.1.1 of TS 38.211v15.3.0. Additionally or alternatively, the UE 101 may be configured with a maximum number of front-loaded DM-RS symbols for the PDSCH via a higher-level parameter maxLength given by DMRS-DownlinkConfig. If maxLength is set to "len1", a single symbol DM-RS may be scheduled for the UE via DCI, and the UE 101 may be configured with multiple additional DM-RSs for the PDSCH via a higher-level parameter dmrs-AdditionalPosition, which may be set to "position 0", "position 1", "position 2", or "position 3". If maxLength is set to "length 2", both single symbol DM-RS and dual symbol DM-RS may be scheduled for UE 101 via DCI, and UE 101 may be configured with multiple additional DM-RS for PDSCH via the higher layer parameter dmrs-AdditionalPosition, which may be set to "position 0" or "position 1". Additionally or alternatively, UE 101 assumes reception of additional DM-RS as specified in Tables 3 and 4, as described in subclause 7.4.1.1.2 of TS 38.211 v15.3.0.

[0038] For UE-specific reference signal generation defined in subclause 7.4.1.1 of TS 38.211 v15.3.0, UE 101 may be identified by one or two scrambling codes. For the higher layer configuration of i=0,1, for both PDSCH mapping type A and type B, the scrambling code identifier is the same.

[0039] UE 101 may be scheduled with multiple DM-RS ports via antenna port index in DCI format 1 1, as described in subclause 7.3.1.2 of TS 38.212 v15.3.0. For DM-RS configuration type 1, if UE 101 is scheduled with one codeword and is assigned an antenna port mapping with index {2, 9, 10, 11, or 30} in Table 7.3.1.2.2-1 and Table 7.3.1.2.2-2 in subclause 7.3.1.2 of TS 38.212 v15.3.0, or if UE 101 is scheduled with two codewords, UE 101 may assume that all remaining orthogonal antenna ports are not associated with transmission of PDSCH to another UE 101.

[0040] For DM-RS configuration type 2, if UE 101 is scheduled with one codeword and is assigned an antenna port mapping with index {2, 10 or 23} in Table 7.3.1.2.2-3 and Table 7.3.1.2.2-4 in subclause 7.3.1.2 of TS 38.212 v15.3.0, or if UE 101 is scheduled with two codewords, UE 101 may assume that all remaining orthogonal antenna ports are not associated with transmission of PDSCH to another UE 101.

[0041] By setting the higher layer parameter maxLength equal to "length 2" and giving more than one additional DM-RS symbol by the higher layer parameter dmrs-AdditionalPosition, it is not expected that the UE 101 is simultaneously configured with the maximum number of front-loaded DM-RS symbols for PDSCH.

[0042] With respect to the actual number of front-loaded DM-RS symbols, the actual number of additional DM-RS, the DM-RS symbol positions, and the DM-RS configuration type, it is not expected that UE 101 assumes co-scheduled UEs with different DM-RS configurations, as described herein and in subclause 7.4.1.1 of TS38.211v15.3.0.

[0043] UE 101 does not expect the precoding of potential co-scheduled UEs in other DM-RS ports of the same CDM group to be different in the PRG level grid configured for UE 101 with PRG=2 or 4. UE 101 does not expect the resource allocation of potential co-scheduled UEs in other DM-RS ports of the same CDM group to be misaligned in the PRG level grid configured for UE 101 with PRG=2 or 4. When receiving a PDSCH scheduled by DCI format 1_1, UE 101 assumes that the CDM groups indicated in the configuration indexes of 7.3.1.2.2-1, 7.3.1.2.2-2, 7.3.1.2.2-3, 7.3.1.2.2-4 of Tables TS 38.212v15.3.0 contain potential co-scheduled downlink DM-RS and are not used for data transmission, where the number of DM-RS CDM groups "1", "2" and "3" in Tables 7.3.1.2.2-1, 7.3.1.2.2-2, 7.3.1.2.2-3, 7.3.1.2.2-4 of TS 38.212v15.3.0 corresponds to CDM groups 0, {0,1}, {0,1,2}, respectively.

[0044] When receiving a PDSCH scheduled by DCI format 1_0, UE 101 assumes that the number of DM-RS CDM groups without data is 1, which corresponds to CDM group 0 for a PDSCH with an allocation duration of 2 symbols, and UE 101 assumes that the number of DM-RS CDM groups without data is 2, which corresponds to CDM groups {0,1} for all other cases.

[0045] It is undesirable for a UE 101 to receive a PDSCH scheduling DCI indicating a CDM group with potential DM-RS ports overlapping with any configured CSI-RS resources of the UE 101 .

[0046] If UE 101 receives DM-RS and SS / PBCH blocks for PDSCH in the same OFDM symbol, then if "QCL-Type D" is applicable, UE 101 may assume that the DM-RS and SS / PBCH blocks are quasi-co-located with "QCL-Type D". In addition, UE 101 may not expect to receive DM-RS in resource elements that overlap with resource elements of SS / PBCH blocks, and UE 101 may expect the same or different subcarrier spacing to be configured for DM-RS and SS / PBCH blocks in a CC, except for the case of 240kHz where only different subcarrier spacing is supported.

[0047] In addition, UE 101 may be configured with a list of up to M TCI-state (TCI-State) configurations within the high-level parameter PDSCH-Config (PDSCH-Config) to decode the PDSCH based on a detected PDCCH with DCI intended for UE 101 and a given serving cell, where M is a number and depends on the UE capability maxNumberActiveTCI-PerBWP. Each TCI-state contains parameters for configuring a quasi-co-site (QCL) relationship between one or two DL RSs and a DM-RS port of a PDSCH, a DM-RS port of a PDCCH, or a CSI-RS port of a CSI-RS resource. The QCL relationship is configured by the high-level parameters qcl-Type1 (qcl-type 1) of the first DL RS and qcl-Type2 (qcl-type 2) of the second DL RS (if configured). For the case of two DL RSs, the QCL type is different regardless of whether the reference is to the same DL RS or to different DL RSs. The QCL type corresponding to each DL RS is given by the high-level parameter qcl-Type in QCL-Info, and can take one of the following values: "QCL-Type A": {Doppler shift, Doppler spread, average delay, average spread}; "QCL-Type B": {Doppler shift, Doppler spread}; "QCL-Type C": {Doppler shift, average delay}; and / or "QCL-Type D": {spatial Rx parameters}.

[0048] UE 101 may receive an activation command as described in subclause 6.1.3.14 of 3GPP TS 38.321 v15.3.0 (2018-09) for mapping up to 8 transmission configuration indicator / indication (TCI) states to code points of the DCI field "Transmission Configuration Indication". When a HARQ-ACK corresponding to a PDSCH carrying an activation command is transmitted in time slot n, the HARQ-ACK corresponding to the PDSCH carrying the activation command shall be transmitted from time slot n. Starting from the first timeslot thereafter, the indicated mapping between the TCI states and the code points of the DCI field "Transmission Configuration Indication" applies. After the UE 101 receives the initial higher layer configuration of the TCI states, and before receiving the activation command, the UE 101 may assume that the DM-RS ports of the PDSCH of the serving cell are quasi-co-located with the SS / PBCH blocks determined during the initial access procedure with respect to "QCL-Type A" and, when applicable, also with respect to "QCL-Type D".

[0049] If the UE 101 is configured with the higher layer parameter tci-PresentInDCI set to "enabled" for the CORESET scheduling PDSCH, the UE 101 assumes that the TCI field is present in DCI format 1_1 of the PDCCH transmitted on the CORESET. If tci-PresentInDCI is not configured for the CORESET scheduling PDSCH or the PDSCH is scheduled by DCI format 1_0, and the time offset between the reception of the DL DCI and the corresponding PDSCH is equal to or greater than a threshold timeDurationForQCL (duration for QCL), where the threshold is based on the reported UE capabilities 3GPP TS 38.306 v15.2.0 (2018-06), for the purpose of determining PDSCH antenna port quasi co-location, the UE 101 assumes that the TCI state or QCL assumption for the PDSCH is the same as whatever TCI state or QCL assumption applied to the CORESET for PDCCH transmission.

[0050] If tci-PresentInDCI is set to "enabled", the TCI field in the DCI in the scheduled component carrier points to the activated TCI state in the scheduled component carrier or DL ​​BWP, and when the PDSCH is scheduled by DCI format 1_1, the UE 101 uses the TCI state according to the value of the "Transmission Configuration Indication" field in the detected PDCCH with the DCI for determining the PDSCH antenna port quasi-co-location. If the time offset between the reception of the DL DCI and the corresponding PDSCH is equal to or greater than the threshold timeDurationForQCL, the UE 101 may assume that the DM-RS ports of the PDSCH of the serving cell are quasi-co-located with the RS in the TCI state relative to the QCL type parameter given by the indicated TCI state, where the threshold is based on the reported UE capabilities 3GPP TS 38.306 v15.2.0 (2018-06). When the UE 101 is configured with a single slot PDSCH, the indicated TCI state should be based on the activated TCI state in the slot with the scheduled PDSCH. When the UE 101 is configured with a multi-slot PDSCH, the indicated TCI state shall be based on the activated TCI state in the first slot with scheduled PDSCH, and the UE 101 expects the activated TCI state to be the same on the slots with scheduled PDSCH. When the UE 101 is configured with a CORESET associated with a search space set for cross-carrier scheduling, the UE 101 expects tci-PresentInDci to be set to "enabled" for the CORESET, and if one or more of the TCI states configured for the serving cells scheduled by the search space set includes "QCL-Type D", the UE 101 expects the time offset between the reception of the PDCCH detected in the search space set and the corresponding PDSCH to be greater than or equal to the threshold timeDurationForQCL.

[0051] For both cases where tci-PresentInDCI is set to "enabled" and tci-PresentInDCI is not configured in RRC connected mode, if the offset between the reception of the DL DCI and the corresponding PDSCH is less than the threshold timeDurationForQCL, the UE 101 may assume that the DM-RS ports of the PDSCH of the serving cell are quasi-co-located with the RS relative to the QCL parameters of the PDCCH quasi-co-location indication for the CORESET associated with the monitored search space with the lowest CORESET-ID in the most recent slot, where one or more CORESETs within the active BWP of the serving cell are monitored by the UE 101. In this case, if the "QCL-Type D" of the PDSCH DM-RS is different from the "QCL-Type D" of the PDCCH DM-RS with which they overlap in at least one symbol, the UE 101 is expected to prioritize the reception of the PDCCH associated with the CORESET. This also applies to the intra-band CA case (when the PDSCH and the CORESET are in different component carriers). If none of the configured TCI states of the serving cell of a scheduled PDSCH contains "QCL-Type D", UE 101 derives other QCL assumptions from the indicated TCI state of its scheduled PDSCH regardless of the time offset between reception of the DL DCI and the corresponding PDSCH.

[0052] For the DM-RS of the PDCCH, the UE 101 expects the TCI-State to indicate one of the following quasi-co-location types: "QCL-Type A" with CSI-RS resources in an NZP-CSI-RS-ResourceSet configured with the higher-level parameter trs-Info, and "QCL-Type D" with the same CSI-RS resources when applicable; "QCL-Type D" with CSI-RS resources in an NZP-CSI-RS-ResourceSet configured with the higher-level parameter trs-Info. "QCL-Type A" of CSI-RS resources, and when applicable, "QCL-Type D" having CSI-RS resources in an NZP-CSI-RS-resource set configured with the higher-level parameter repetition; or "QCL-Type A" of CSI-RS resources in an NZP-CSI-RS-resource set not configured with the higher-level parameter trs-Info and not configured with the higher-level parameter repetition, and when applicable, "QCL-Type D" having the same CSI-RS resources.

[0053] For the DM-RS of the PDSCH, the UE 101 expects the TCI-state to indicate one of the following quasi-co-location types: "QCL-Type A" with CSI-RS resources in the NZP-CSI-RS-resource set configured with the higher-level parameter trs-Info, and "QCL-Type D" with the same CSI-RS resources when applicable; "QCL-Type A" with CSI-RS resources in the NZP-CSI-RS-resource set configured with the higher-level parameter trs-Info, and "QCL-Type D" with CSI-RS resources in the NZP-CSI-RS-resource set configured with the higher-level parameter repetition when applicable, or "QCL-Type A" with CSI-RS resources in the NZP-CSI-RS-resource set not configured with the higher-level parameter trs-Info and not configured with the higher-level parameter repetition, and "QCL-Type D" with the same CSI-RS resources when applicable.

[0054] Figure 3 Multiple examples of multi-TRP and multi-DCI operations are shown. In the case where DMRS is transmitted and received from multiple TRPs, there may be different cases, namely based on a single DCI or multiple DCI. Example scenario 300a-1 shows DCI (DPS) dynamically transmitted from TRP_0 (of RAN node 111a) for frequency range 2 (FR2), and example scenario 300a-2 shows DCI dynamically transmitted from TRP0 (of RAN node 111a) for frequency range 1 (FR1) using dynamic point switching (DPS). Example scenario 300b-1 shows DCI dynamically transmitted from TRP_1 (of RAN node 111b) for FR2, and example scenario 300b-2 shows FR1a DCI (DPS) dynamically transmitted from TRP2 (of RAN node 111b). Example scenario 300c-1 shows DCI transmitted from TRP_0 (of RAN node 111a) and TRP_1 (of RAN node 111b) in an orthogonal manner (e.g., repetition) or SFN (subframe number or system frame number) manner for FR2. Example scenario 300c-2 shows DCI transmitted from TRP_0 (of RAN node 111a) and TRP_1 (of RAN node 111b) in an orthogonal manner or SFN manner for FR1. DPS refers to the ability of UE 101 to switch between two TRPs for PDSCH reception / PUSCH transmission, where transmission to / reception from only one TRP occurs at any given time instance.

[0055] According to various implementations, the configured DM-RS ports may be subdivided into one or more DM-RS antenna port groups (or simply referred to as "DM-RS port groups", etc.). The grouping of DM-RS ports may be based on whether a single DCI-based multi-TRP transmission scheme and / or a multi-DCI-based multi-TRP transmission scheme is used.

[0056] Single DCI multiple TRP transmission solution

[0057] In one embodiment, the DM-RS port group may be a predefined DMRS port set such that all ports within the CDM group belong to the same DMRS-port group. For example, for type 1 DM-RS, the DM-RS port group may include the following port group set {0, CDM-group 1, CDM-group 2, CDM-group 1+2}, where 0 indicates that no DMRS-port group is configured. In this embodiment, the CDM group means that all ports mapped to the CDM group are part of the DMRS port group. For type 2 DMRS, the configurable group set may be given by {0, CDM-group 1, CDM-group 2, CDM-group 3, CDM-group 1+2, CDM-group 1+3, CDM-group 2+3, CDM-group 1+2+3} or a subset thereof.

[0058] In one embodiment, the DMRS port group configuration may be semi-statically signaled to the UE 101 using a high-level parameter DMRS-Port-Group (DMRS-Port Group) (e.g., in an appropriate RRC message). The parameter DMRS-Port-Group may have a value {0, 1}, where 0 indicates no DMRS-Port Group configuration and 1 indicates a possible DMRS-Port Group configuration. When the UE 101 is configured with one or more DMRS-Port-Groups having a value of 1, the actual DM-RS port group to be used may be dynamically indicated via DCI signaling from a predetermined configurable group value as discussed previously.

[0059] In one embodiment, the port set corresponding to the DMRS-port group may be dynamically indicated to the UE 101 through DCI signaling with or without RRC DMRS-port group configuration.

[0060] Additionally or alternatively, each DMRS port group configured to UE 101 may correspond to transmissions from a single TRP. In this embodiment, UE 101 may implicitly determine the MIMO layers arriving from different TRPs from the DMRP port group configuration. This embodiment may utilize dynamic and semi-static signaling, or may use only dynamic DCI-based indications.

[0061] Additionally or alternatively, multiple DMRS-port groups may be associated with the same TRP. In this embodiment, the transmission configuration indicator / indication (TCI) may be enhanced to support two QCL information for different DM-RS antenna port groups. For example, DCI format 1_1 currently includes a TCI field, which is 0 bits if the high-level parameter tci-PresentInDCI is not enabled; otherwise, the field is 3 bits as defined in subclause 5.1.5 of 3GPP TS 38.214v15.2.0 (2018-06). In this embodiment, the DCI (e.g., DCI format 1_1) may include a second TCI field indicating additional QCL information for a second DM-RS port group. Alternatively, the TCI field / data structure in the RRC configuration, DCI, or MAC control element (CE) TCI code point may be extended or expanded to support additional QCL information for a second DM-RS port group. Additionally or alternatively, each DMRS-port group may be associated with a different TCI state.

[0062] Additionally or alternatively, in addition to the signaling support available in Rel-15 NR DMRS antenna port indication tables 7.3.1.1.2-6 to 7.3.1.1.2-23 for UL DM-RS indication in TS 38.212v15.3.0 and tables 7.3.1.2.2-2 to 7.3.1.2.2-4 for DL ​​DMRS indication in TS38.212v15.3.0, cross-CDM group DMRS port scheduling support is introduced. For example, for level 3 transmission with type 1 single symbol DMRS, an option for signaling DMRS antenna ports 0, 2, and 3 may be included. In this case, port 0 from CDM-group 1 may belong to DMRS port group 1, and ports 2 and 3 from CDM-group 2 may belong to DMRS port group 2. When one or more DMRS port groups are associated with different TRPs, UE101 may implicitly determine the layer group received from the same TRP.

[0063] In one embodiment, the DMRS port groups configured for UE 101 may include ports from different CDM groups. For example, in the case of a single symbol type 1 DMRS, the first DMRS-port group may include ports {0, 1, 2}, and the second DMRS-port group may include port 3.

[0064] Additionally or alternatively, the DM-RS CDM groups may contain different DMRS-port groups, and the total number of TRPs that may be orthogonally transmitted to the UE 101 is limited only by the total number of MIMO layers supported in the downlink.

[0065] Additionally or alternatively, DMRS ports in the same DMRS port group may be spatially QCLed. In this case, the UE 101 receives a single DCI and may be dynamically configured with the DMRS port group.

[0066] In one embodiment, multi-TRP DM-RS transmissions to UE 101 may be configured in a transparent manner in UE 101, where UE 101 is unaware of the identity of the TRP transmitting each MIMO layer.

[0067] Additionally or alternatively, the TRP identity of each MIMO layer may be made known to the UE 101 by configuring the DMRS port groups. This may be used to design an advanced receiver at the UE 101 that may have improved interference suppression.

[0068] Additionally or alternatively, each DMRS-port group may have a different cell ID (N) for DMRS PN sequence initialization. ID ) or scrambling code ID (n SCID ). Additionally or alternatively, each CDM group may also have a different cell ID.

[0069] Multi-DCI Multi-TRP Transmission Solution

[0070] In one embodiment, each DCI received by UE 101 may correspond to a different TRP, and UE 101 is configured with a different DMRS-port set with associated DMRS ports for the corresponding TRP. Each PDCCH and corresponding DCI then becomes associated with a different TCI state.

[0071] In addition, the DMRS configuration with respect to DMRS type, number of front-loaded symbols, number and position of additional DMRS symbols within a timeslot should be the same for different TRPs transmitted to the same UE 101.

[0072] Additionally or alternatively, the PDSCH mapping type (e.g., DM-RS mapping type A or DM-RS mapping type B) may be the same when multiple TRPs are transmitted to the same UE 101. In this embodiment, the duration and / or scheduling may be the same or different for each of the multiple TRPs.

[0073] Additionally or alternatively, the PDSCH mapping types (e.g., PDSCH mapping type A or PDSCH mapping type B) for multiple TRPs transmitted to the same UE 101 may have different time domain durations. In this embodiment, the UE 101 may assume that the same DMRS configuration is applicable in terms of the DMRS type, position, and number of additional DMRS symbols from the multiple TRPs. The UE 101 may implicitly determine the presence of additional DMRS symbols from each TRP by the scheduled time domain duration. If the additional DMRS symbols configured for the UE 101 fall outside the time domain duration of the scheduled PDSCH from a given TRP, it may be assumed that they are discarded from the UE 101 perspective for the MIMO layer transmitted from that TRP.

[0074] Additionally or alternatively, the PDSCH mapping type (e.g., PDSCH mapping type A or PDSCH mapping type B) for different TRPs transmitted to the same UE 101 can be different. The DMRS configuration type can be the same, but the additional DMRS symbols and positions can be different. In this embodiment, the UE 101 can still assume the same DMRS configuration, but the number and position of the additional DMRS can implicitly depend on the time domain duration of the PDSCH mapping from each TRP.

[0075] Additionally or alternatively, the PDSCH mapping type (e.g., PDSCH mapping type A or PDSCH mapping type B) for different TRPs transmitted to the same UE 101 may be different. The DMRS configuration type may also be different for different DCIs. In this embodiment, the RRC parameters may be extended to support multiple DMRS configuration types. The UE 101 may be expected to be configured with DMRS information via high-layer signaling for different DCIs.

[0076] Additionally or alternatively, multiple TRPs may transmit DMRS in a quasi-orthogonal manner. Quasi-orthogonal transmission may involve using the same time-frequency resources and different PN sequences with different seed values, resulting in low cross-correlation of the sequences used in the quasi-orthogonal ports. Quasi-orthogonal transmission of DMRS may be used when the DMRS resources are not completely orthogonal to each other, such as when the cross-correlation is 0.

[0077] Exemplary Implementations

[0078] UE 101, RAN node 111, AP 106, network element 122, application server 130 and / or previously related Figure 1 Each of any other devices or systems discussed in connection with FIG. 6 may include various hardware and / or software elements, such as those described below with respect to FIG. Figure 4 and Figure 5 those discussed.

[0079] Figure 4 An example of infrastructure equipment 400 according to various embodiments is illustrated. Infrastructure equipment 400 (or "system 400") can be implemented as a base station, a radio head, a RAN node (such as the RAN node 111 and / or AP 106 shown and described previously), an application server 130, and / or any other element / device discussed herein. In other examples, system 400 can be implemented in or by a UE.

[0080] System 400 includes: application circuit 405, baseband circuit 410, one or more radio front end modules (RFEM) 415, memory circuit 420, power management integrated circuit (PMIC) 425, power three-way circuit 430, network controller circuit 435, network interface connector 440, satellite positioning circuit 445 and user interface 450. In some embodiments, device 400 may include additional elements, such as, for example, memory / storage, display, camera, sensor or input / output (I / O) interface. In other embodiments, the above components may be included in more than one device. For example, the circuit may be separately included in more than one device for CRAN, vBBU or other similar specific implementations. The term "circuit" as used herein refers to a circuit or a system of multiple circuits configured to perform a specific function in an electronic device. A circuit or system of circuits may be part of or include one or more hardware components configured to provide the functions, such as logic circuits, processors (shared, dedicated or group) and / or memories (shared, dedicated or group), integrated circuits (ICs), application specific ICs (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), etc. In addition, the term "circuit" may also refer to a combination of one or more hardware elements and program code for executing the functions of the program code. Some types of circuits may execute one or more software or firmware programs to provide at least some of the functions. Such combinations of hardware elements and program codes may be referred to as specific types of circuits. As used herein, the term "processor circuit" refers to a circuit capable of sequentially and automatically performing a sequence of arithmetic or logical operations or recording, storing and / or transmitting digital data and / or any other device capable of executing or otherwise operating computer executable instructions such as program code, software modules and / or functional processes, being a part of or including them. As used herein, the term "module" refers to one or more independent electronic circuits packaged on a circuit board, FPGA, ASIC, SoC, SiP, etc., configured to provide basic functions within a computer system. A "module" may include a processor circuit (shared, dedicated, or group) and / or a memory circuit (shared, dedicated, or group) that executes one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that provide the functionality. As used herein, the term "interface circuit" may refer to, be part of, or include: a circuit that provides information exchange between two or more components or devices. The term "interface circuit" refers to one or more hardware interfaces, such as a bus, an input / output (I / O) interface, a peripheral component interface, a network interface card, and the like.

[0081] The application circuit 405 includes, for example, but not limited to, one or more processors (or processor cores), cache memory, and one or more low dropout regulators (LDO), an interrupt controller, a serial interface such as SPI, 2 C or general programmable serial interface module, real-time clock (RTC), timer-counter including interval timer and watchdog timer, general input / output (I / O or IO), memory card controller such as secure digital (SD) multimedia card (MMC) or similar products, universal serial bus (USB) interface, mobile industry processor interface (MIPI) interface and joint test access group (JTAG) test access port. The processor (or core) of application circuit 405 can be coupled with memory / storage element or can include memory / storage element, and can be configured to execute instructions stored in memory / storage element to enable various applications or operating systems to run on system 400. In some specific implementations, the memory / storage element can be an on-chip memory circuit, which can include any suitable volatile and / or non-volatile memory, such as DRAM, SRAM, EPROM, EEPROM, flash memory, solid-state memory and / or any other type of memory device technology, such as those discussed herein.

[0082] The processor of the application circuit 405 may include, for example, one or more processor cores (CPUs), one or more application processors, one or more graphics processing units (GPUs), one or more reduced instruction set computing (RISC) processors, one or more Acorn RISC Machine (ARM) processors, one or more complex instruction set computing (CISC) processors, one or more digital signal processors (DSPs), one or more FPGAs, one or more PLDs, one or more ASICs, one or more microprocessors or controllers, or any suitable combination thereof. In some embodiments, the application circuit 405 may include or may be a dedicated processor / controller for operating according to various embodiments herein. As an example, the processor of the application circuit 405 may include one or more Intel or Processor: Advanced Micro Devices (AMD) Processor, Accelerated Processing Unit (APU) or processors; ARM-based processors licensed from ARM Holdings, LTD., such as the ARM Cortex-A series processors provided by Cavium (TM), Inc. and MIPS-based designs from MIPS Technologies, Inc., such as the MIPS Warrior P-class processor; etc. In some embodiments, system 400 may not utilize application circuit 405, and instead may include a dedicated processor / controller to process IP data received, for example, from an EPC or 5GC.

[0083] In some implementations, the application circuit 405 may include one or more hardware accelerators, which may be microprocessors, programmable processing devices, etc. The one or more hardware accelerators may include, for example, computer vision (CV) and / or deep learning (DL) accelerators. For example, the programmable processing device may be one or more field programmable devices (FPDs), such as field programmable gate arrays (FPGAs), etc.; programmable logic devices (PLDs), such as complex PLDs (CPLDs), high capacity PLDs (HCPLDs), etc.; ASICs, such as structured ASICs, etc.; programmable SoCs (PSoCs); etc. In such implementations, the circuits of the application circuit 405 may include logic blocks or logic architectures, as well as other interconnected resources that may be programmed to perform various functions, such as the processes, methods, functions, etc. of the various embodiments discussed herein. In such an embodiment, the circuitry of the application circuit 405 may include a memory unit (e.g., an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a static memory (e.g., a static random access memory (SRAM), an anti-fuse, etc.)) for storing logic blocks, logic architectures, data, etc. in a look-up table (LUT), etc.

[0084] The baseband circuit 410 may be implemented, for example, as a solder-in substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board, or a multi-chip module containing two or more integrated circuits. The baseband circuit 410 includes one or more processing devices (e.g., baseband processors) for performing various protocols and radio control functions. The baseband circuit 410 may interact with the application circuits of the system 400 to generate and process baseband signals and control the operation of the RFEM circuit 415. The baseband circuit 410 may handle various radio control functions to implement communication with one or more radio networks via the RFEM 415. The baseband circuit 410 may include circuits such as, but not limited to, one or more single-core or multi-core processors (e.g., one or more baseband processors) or control logic components to process baseband signals received from a receive signal path of the RFEM 415 and generate baseband signals to be provided to the RFEM 415 via a transmit signal path. In various embodiments, the baseband circuit 410 may implement an RTOS to manage resources of the baseband circuit 410, schedule tasks, etc. Examples of an RTOS may include a processor that is configured to perform a RTOS. Operating System Embedded (OSE) provided TM , by Mentor Nucleus RTOS provided TM , by Mentor Versatile Real-Time Executive (VRTX) provided by Express Provided by ThreadX TM ,Depend on FreeRTOS and REX OS provided by Open Kernel (OK) OKL4 provided, or any other suitable RTOS, such as those discussed herein.

[0085] User interface circuitry 450 may include one or more user interfaces designed to enable a user to interact with system 400 or a peripheral component interface designed to enable a peripheral component to interact with system 400. User interfaces may include, but are not limited to, one or more physical or virtual buttons (e.g., a reset button), one or more indicators (e.g., light emitting diodes (LEDs)), a physical keyboard or keypad, a mouse, a touch pad, a touch screen, a speaker or other audio transmitting device, a microphone, a printer, a scanner, a headset, a display screen or display device, etc. Peripheral component interfaces may include, but are not limited to, a non-volatile memory port, a universal serial bus (USB) port, an audio jack, a power interface, etc.

[0086] The radio front end module (RFEM) 415 may include a millimeter wave (mm-wave) RFEM and one or more sub-mm-wave radio frequency integrated circuits (RFICs). In some implementations, the one or more sub-mm-wave RFICs may be physically separated from the mm-wave RFEM. The RFIC may include connections to one or more antennas or antenna arrays, and the RFEM may be connected to multiple antennas. In alternative implementations, both mm-wave and sub-mm-wave radio functionality may be implemented in the same physical RFEM 415 incorporating both mm-wave antennas and sub-mm-waves.

[0087] The memory circuit 420 may include one or more of the following: a volatile memory such as a dynamic random access memory (DRAM) and / or a synchronous dynamic random access memory (SDRAM), a non-volatile memory (NVM) including a high-speed electrically erasable memory (commonly referred to as a "flash memory"), a phase change random access memory (PRAM), a magnetoresistive random access memory (MRAM), etc., and may be combined with and The memory circuit 420 may be implemented as one or more of the following: a solder-in package integrated circuit, a socket memory module, and a plug-in memory card.

[0088] The PMIC 425 may include a voltage regulator, a surge protector, a power alarm detection circuit, and one or more backup power sources, such as a battery or capacitor. The power alarm detection circuit may detect one or more of a brownout (undervoltage) and a surge (overvoltage) condition. The power tee circuit 430 may provide power extracted from the network cable to provide both power and data connections for the infrastructure equipment 400 using a single cable.

[0089] The network controller circuit 435 can provide a connection to the network using a standard network interface protocol such as Ethernet, Ethernet based on a GRE tunnel, Ethernet based on a multi-protocol label switching (MPLS), or some other suitable protocol. A physical connection can be used to provide a network connection to / from the infrastructure equipment 400 via a network interface connector 440, which can be an electrical connection (commonly referred to as a "copper interconnect"), an optical connection, or a wireless connection. The network controller circuit 435 may include one or more dedicated processors and / or FPGAs for communicating using one or more of the aforementioned protocols. In some specific implementations, the network controller circuit 435 may include multiple controllers for providing connections to other networks using the same or different protocols.

[0090] The positioning circuit 445 includes circuits for receiving and decoding signals transmitted / broadcasted by the positioning network of the global navigation satellite system (GNSS). Examples of navigation satellite constellations (or GNSS) include the Global Positioning System (GPS) of the United States, the Global Navigation System (GLONASS) of Russia, the Galileo system of the European Union, the Beidou Navigation Satellite System of China, regional navigation systems or GNSS augmentation systems (e.g., using the Indian constellation (NAVIC), the Quasi-Zenith Satellite System (QZSS) of Japan, the Doppler Orbit Chart and Satellite Integrated Radio Positioning (DORIS) of France, etc. for navigation), etc. The positioning circuit 445 includes various hardware elements (e.g., including hardware devices such as switches, filters, amplifiers, antenna elements, etc. for facilitating OTA communication) to communicate with components of the positioning network such as navigation satellite constellation nodes. In some embodiments, the positioning circuit 445 may include a micro technology (micro PNT) IC for positioning, navigation and timing, which uses a master timing clock to perform position tracking / estimation without GNSS assistance. The positioning circuit 445 may also be part of or interact with the baseband circuit 410 and / or the RFEM 415 to communicate with nodes and components of the positioning network. The positioning circuit 445 may also provide location data and / or time data to the application circuit 405, which may use the data to synchronize operations with various infrastructure (e.g., RAN node 111, etc.), etc.

[0091] Figure 4 The components shown may communicate with each other using an interface circuit 406 or IX 406, which may include any number of bus and / or IX technologies, such as an Industry Standard Architecture (ISA), an Extended ISA, an Inter-Integrated Circuit (I 2 C), Serial Peripheral Interface (SPI), Point-to-Point Interface, Power Management Bus (PMBus), Peripheral Component Interconnect (PCI), PCI express (PCIe), PCI extension (PCIx), Super Path Interconnect (UPI), Accelerator Link (IAL), Coherent Accelerator Processor Interface (CAPI), OpenCAPI, QuickPath Interconnect (QPI), Omni-Path Architecture (OPA) IX, RapidIO TM System IX, Cache Coherent Interconnect for Accelerators (CCIA), Gen-Z Consortium IX, HyperTransport Interconnect, and / or any number of other IX technologies. The IX technology may be a proprietary bus, such as used in SoC-based systems.

[0092] Figure 5An example of a communication circuit 500 that may be used to practice the embodiments discussed herein is shown. Figure 5 The components shown are shown for illustrative purposes and may include Figure 5 other components not shown, or Figure 5 The elements shown may alternatively be grouped according to function.

[0093] The communication circuit 500 includes a protocol processing circuit 505, which operates or implements various protocol layers / entities of one or more wireless communication protocols. In one example, when the communication circuit 500 is a cellular radio frequency communication system such as a millimeter wave (mm wave) communication circuit or some other suitable cellular communication circuit, the protocol processing circuit 505 can operate a long-term evolution (LTE) protocol entity and / or a fifth generation (5G) / new air interface (NR) protocol entity. In this example, the protocol processing circuit 505 will operate medium access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), radio resource control (RRC) and non-access layer (NAS) functions. In another example, when the communication circuit 500 is a WiFi communication system, the protocol processing circuit 505 can operate one or more IEEE-based protocols. In this example, the protocol processing circuit 505 will operate MAC and logical link control (LLC) functions.

[0094] The protocol processing circuit 505 may include one or more memory structures (not shown) for storing program code and data information for operating protocol functions, and one or more processing cores (not shown) for executing program code and performing various operations using data information. The protocol processing circuit 505 may include one or more instances of control circuits (not shown) to provide control functions for the digital baseband circuit 510, the transmission circuit 515, the reception circuit 520, and / or the radio frequency (RF) circuit 525. In some embodiments, the protocol processing circuit 505 and / or the baseband circuit 510 correspond to Figure 4 Baseband circuit 410.

[0095] The communication circuit 500 also includes a digital baseband circuit 510, which implements physical layer (PHY) functions, including: hybrid automatic repeat request (HARQ) functions, scrambling and / or descrambling, encoding and / or decoding, layer mapping and / or demapping, modulation symbol mapping, received symbol and / or bit metric determination, multi-antenna port encoding and / or decoding, which may include space-time, space-frequency or space coding, reference signal generation and / or detection, preamble sequence generation and / or decoding, synchronization sequence generation and / or detection, control channel signal blind decoding, radio frequency shift and other related functions. One or more. The modulation / demodulation function may include a fast Fourier transform (FFT), precoding or constellation mapping / demapping function. The encoding / decoding function may include convolution, tail-truncation convolution, turbo, Viterbi, low-density parity check (LDPC) coding, polar coding, etc. The implementation of the modulation / demodulation and encoder / decoder functions is not limited to these examples, and other suitable functions may be included in other implementations.

[0096] The baseband processing circuit 510 and / or the protocol processing circuit 505 may be connected to an application platform (eg, Figure 4 The digital baseband circuit 510 may interact with the application circuit 405 of the RF circuit 525 for baseband signal generation and processing and for controlling the operation of the RF circuit 525. The digital baseband circuit 510 may handle various radio control functions that enable communication with one or more radio networks via the R circuit 525. The digital baseband circuit 510 may include circuits such as, but not limited to, one or more single-core or multi-core processors (e.g., one or more baseband processors) or control logic components to process baseband signals received from the receive signal path of the RF circuit 525 (e.g., via the Rx circuit 520) and generate baseband signals for the transmit signal path of the RF circuit 525 (e.g., via the Tx circuit 515). The digital baseband circuit 510 may include a multi-protocol baseband processor, etc.

[0097] As previously described, the digital baseband circuit 510 may include or implement an encoder circuit that accepts input data, generates coded data based on the input data, and outputs the coded data to a modulation mapper. The encoder may also perform one or more of error detection, error correction, rate matching, and interleaving. The encoder may also include a scrambling code based on a scrambling code sequence such as those discussed herein.

[0098] In various embodiments, the digital baseband circuit 510 may include or implement a sequence generator to generate, for example, a low peak-to-average power ratio (low PAPR) sequence (see, for example, Section 5.2.2 of TS 38.211 v15.3.0), a pseudo-random noise (PN) sequence (see, for example, Section 5.2.1 of TS 38.211 v15.3.0), and / or a reference signal sequence. In some embodiments, the sequence generator may be part of an encoder circuit. The PN sequence consists of bits (e.g., 1s and 0s) that should be random. The PN sequence generator may include a linear feedback shift register (LSFR) to generate the PN sequence. A scrambling code based on a GOLD code is used to scramble a physical signal before transmission. The GOLD code is obtained by combining two PN sequences and performing a modulo-2 addition or an exclusive-OR (XOR) operation on the PN sequence. In an embodiment, the sequence generator is used for QPSK modulation using a pseudo-random GOLD sequence c(n), which is obtained by combining two M sequences x1 and x2 of length 31, as described herein.

[0099] For example, a universal pseudo-random sequence is defined by a length 31 Gold sequence, where the length is M PN The output sequence c(n) (where 0,1,...,M PN -1) is defined by the following formula:

[0100] c(n)=(x1(n+N c )+x Z (n+N C ))mod2

[0101] x1(n+31)=(x1(n+3)+x1(n))mod2

[0102] x2(n+31)=(x2(n+3)+x2(n+2)+x2(n+1)+x2(n))mod2

[0103] Where Nc = 1600 and the first m-sequence x1(n) is initialized with x1(0) = 1, x1(n) = 0, n = 1, 2, ..., 30. In this example, "c(2n)" and "c(2n+1)" in the reference signal sequence formula may refer to the PN sequence c(n). The second m-sequence x2(n) is initialized by represents, whose value depends on the application of the sequence, where c init is the initialization condition or initialization seed value of the second m-sequence x2(n).

[0104] In various embodiments, the sequence generator generates a DM-RS sequence including a pseudo-random sequence. For example, UE 101 may assume that the sequence r(n) of the DM-RS for PDSCH is defined by:

[0105]

[0106] The pseudo-random sequence c(i) is defined in clause 5.2.1 of TS 38.211v15.3.0. The pseudo-random sequence generator is initialized as:

[0107]

[0108] where j is an imaginary unit / number equal to the square root of -1 (e.g. ), l is the number of OFDM symbols in a time slot; n μ s,f is the number of time slots in the frame; if provided, N 0 ID 、N 1 ID ∈{0,1,…,65535} are given by the higher layer parameters scramblingID0 and scramblingID1 in the DMRS-DownlinkConfig IE, respectively, and PDSCH is scheduled by PDCCH using DCI format 1_1 with CRC scrambled by C-RNTI, MCS-C-RNTI or CS-RNTI; if provided, N 0 ID ∈{0,1,...,65535} is given by the higher layer parameter scramblingID0 in the DMRS-Downlink Configuration IE, and the PDSCH is scheduled by the PDCCH using DCI format 1_0 with CRC scrambled by C-RNTI, MCS-C-RNTI or CS-RNTI; otherwise And if DCI format 1_1 in TS38.212v15.3.0 is used, the number n SCID ∈{0,1} is given by the DM-RS sequence initialization field in the DCI associated with the PDSCH transmission, otherwise n SCID =0.

[0109] UE 101 may assume that the sequence r of the DM-RS used for the PDCCH l (m) is defined by the above equation, using r l UE 101 may assume that the sequence r(m) of the DM-RS for the PBCH is defined by the above equation, replacing r(n) with m and n with m, and as further discussed in clause 7.4.1.3 of TS 38.211 v15.3.0. l(m) replaces r(n) and n is replaced by m, and as further discussed in clause 7.4.1.4 of TS 38.211 v15.3.0.

[0110] In various embodiments, the digital baseband circuit 510 may include or implement a modulation mapper that takes binary digits as input (e.g., encoded data from an encoder) and produces complex-valued modulation symbols as output. For example, for QPSK modulation, pairs of bits b(2i), b(2i+1) are mapped to complex-valued modulation symbols d(i) according to the following formula:

[0111]

[0112] The modulation mapper may operate any other suitable modulation scheme, such as those discussed in section 5.1 of TS 38.211 v15.3.0.The modulation mapper may map groups containing one or more binary digits selected from the encoded data to complex-valued modulation symbols according to one or more mapping tables.

[0113] In some embodiments, the complex-valued modulation symbols may be input to a layer mapper to be mapped to one or more layer-mapped modulation symbol streams. The one or more layer-mapped symbol streams may be input to a precoder that generates one or more precoded symbol streams, which may be represented as vector blocks. The precoder may be configured to perform direct mapping using a single antenna port, transmit diversity using space-time block coding or spatial multiplexing. Each precoded symbol stream may be input to a resource mapper that generates a resource-mapped symbol stream (e.g., resource elements). The resource mapper may map the precoded symbols to frequency domain subcarriers and time domain symbols according to a mapping, which may include contiguous block mapping, random mapping, and / or sparse mapping according to a mapping code.

[0114] According to various embodiments, the modulation mapper (or resource mapper) maps the DM-RS sequence to the physical resources (also referred to as "DM-RS resources", etc.) according to the DMRS configuration type. For example, UE 101 assumes that the PDSCH DM-RS is mapped to the physical resources according to DM-RS configuration type 1 or DM-RS configuration type 2 given by the higher layer parameter dmrs-Type. UE 101 assumes that the sequence r(m) is mapped by the factor Scaled to comply with the transmit power specified in 3GPP TS 38.214v15.2.0 (2018-06) and mapped to resource elements (.k,l) according to p,μ :

[0115]

[0116]

[0117] k′=0,1

[0118]

[0119] n=0,1,...

[0120] where w f (k'), w t (l') and Δ are given by Tables 7.4.1.1.2-1 and 7.4.1.1.2-2, and when the resource element is within a common resource block allocated for PDSCH transmission. If the corresponding PDCCH is associated with CORESET0 and Type 0-PDCCH common search space and is addressed to SI-RNTI, then the reference point for k is subcarrier 0 of the lowest numbered resource block in CORESET 0; otherwise, subcarrier 0 in common resource block 0.

[0121] The reference point of l and the position l0 of the first DM-RS symbol depend on the mapping type. For PDSCH mapping type A, l is defined relative to the start of the time slot, and if the high-level parameter dmrs-TypeA-Position (dmrs-TypeA-Position) is equal to "Position 3", then l0=3, otherwise l0=2. For PDSCH mapping type B, l is defined relative to the start of the scheduled PDSCH resource, and l0=0.

[0122] According to Tables 7.4.1.1.2-3 and 7.4.1.1.2-4, the position of the DM-RS symbol is determined by and duration l d Given, where for PDSCH mapping type A, l d is the duration between the first OFDM symbol of a slot and the last OFDM symbol of a PDSCH resource scheduled in the slot. For PDSCH mapping type B, l d is the duration, is the number of OFDM symbols of the scheduled PDSCH resources. The case where dmrs-AdditionalPosition is equal to "Position 3" is supported only when dmrs-TypeA-Position is equal to "Position 2". For PDSCH mapping type A, l in Tables 7.4.1.1.2-3 and 7.4.1.1.2-4 d = 3 symbols and l d= 4 symbols only applies when dmrs-TypeA-Position is equal to "Position 2". For PDSCH mapping type A single symbol DM-RS, l1 = 11, except that all of the following conditions are met, in which case l1 = 12: the higher-level parameter lte-CRS-ToMatchAround is configured and any PDSCH DM-RS symbol coincides with any symbol containing an LTE cell-specific reference signal, as indicated by the higher-level parameter lte-CRS-ToMatchAround; the higher-level parameter dmrs-AdditionalPosition is equal to "Position 1" and l0 = 3; and UE 101 has indicated that it is capable of additionalDMRS-DL-Alt.

[0123] For PDSCH mapping type B, if PDSCH duration l d is 2, 4, or 7 OFDM symbols for a normal cyclic prefix or 2, 4, or 6 OFDM symbols for an extended cyclic prefix, and the PDSCH allocation conflicts with resources reserved for the search space set associated with the CORESET, then l shall be incremented so that the first DM-RS symbol occurs immediately after the CORESET, and if (a) the PDSCH duration l d If the PDSCH duration is 2 symbols, the UE is not expected to receive DM-RS symbols beyond the second symbol. (b) PDSCH duration l d If the PDSCH duration is 4 symbols, the UE is not expected to receive DM-RS symbols beyond the third symbol. (c) PDSCH duration l d 7 symbols for a normal cyclic prefix or 6 symbols for an extended cyclic prefix, wherein the UE 101 is not expected to receive the first DM-RS beyond the fourth symbol, and if an additional single symbol DM-RS is configured, the UE is only expected to transmit the additional DM-RS on the fifth or sixth symbol when the current loaded DM-RS symbol is in the first or second symbol of the PDSCH duration, respectively, otherwise the UE 101 should expect no additional DM-RS to be transmitted, and / or (d) if the PDSCH duration is l d If the number of OFDM symbols is 2 or 4, only single symbol DM-RS is supported.

[0124] The time domain index l' and the supported antenna ports P are given in Table 5, where if the higher-level parameter maxLength in the DMRS-DownlinkConfigIE is not configured, a single symbol DM-RS is used, and / or if the higher-level parameter maxLength in the DMRS-DownlinkConfigIE is equal to "length 2", a single symbol or dual symbol DM-RS is determined by the associated DCI.

[0125] In the absence of a CSI-RS configuration, and unless configured otherwise, the UE may assume that the PDSCH DM-RS and SS / PBCH blocks are quasi-co-located with respect to Doppler shift, Doppler spread, average delay, delay spread, and (when applicable) spatial Rx parameters. The UE may assume that the PDSCH DM-RS within the same CDM group are quasi-co-located with respect to Doppler shift, Doppler spread, average delay, delay spread, and spatial Rx. The UE may assume that the DMRS port associated with the PDSCH is a QCL with QCL type A, type D (when applicable), and average gain. In addition, the UE 101 may assume that the DM-RS does not conflict with the SS / PBCH block.

[0126] Table 1: Parameters for PDSCH DM-RS configuration type 1

[0127]

[0128] Table 2: Parameters for PDSCH DM-RS configuration type 2

[0129]

[0130] Table 3: PDSCH DM-RS positions for single symbol DM-RS

[0131]

[0132] Table 4: PDSCH DM-RS positions for dual-symbol DM-RS

[0133]

[0134] Table 5: PDSCH DM-RS time index l' and antenna port p

[0135]

[0136] UE 101 assumes that the sequence r of the DM-RS used for PDCCH l (m) is mapped to resource element (k,l) p,μ , as discussed in 7.4.1.3.2 of TS 38.211 v15.3.0. UE 101 assumes that the sequence r(m) of the DM-RS for the PBCH is mapped to resource elements (k, l)p,μ , as described in clause 7.4.3 of TS 38.211v15.3.0.

[0137] In various embodiments, the digital baseband circuit 510 includes or implements a baseband signal generator (also referred to as a "multi-carrier generator") to generate OFDM baseband signals and / or other baseband signals. In these embodiments, the resource mapping symbols from the resource mapper are input to a baseband signal generator that generates time domain baseband symbols. The baseband signal generator can generate a filter bank using, for example, an inverse discrete Fourier transform (usually implemented as an inverse fast Fourier transform (IFFT)) or including one or more filters to generate time domain symbols (e.g., a time domain symbol set). The time domain signal generated by the IFFT is transmitted through a radio channel. At the receiver, the FFT block is used to process the received signal and bring it to the frequency domain for recovering the original data bits.

[0138] For example, the OFDM baseband signal of DM-RS is generated as follows: the time continuous signal s on antenna port p l (p,μ) (t) and the subcarrier spacing configuration μ of OFDM symbol l in a subframe for any physical channel or signal other than PRACH is defined by:

[0139]

[0140]

[0141] in is the time within a subframe,

[0142]

[0143]

[0144] And among them is the resource mapping symbol; k is the subcarrier index; is the number of symbols per time slot; Δf is the SCS (see, for example, Table 6 below) and μ is the SCS configuration; μ0 is the maximum μ value in the subcarrier spacing configuration of the high-level parameter scs-SpecificCarrierList (scs-specific subcarrier list); Configure μ for SCS and the CP length of OFDM symbol l, where in The number of time slots per subframe is configured for subcarrier spacing μ. And is the number of symbols per time slot); is the start of the resource grid, and is the size of the resource grid (where x is “DL” or “UL” for a DL resource grid or a UL resource grid, respectively); is the number of subcarriers for each resource block; T c is the basic time unit of NR; and the starting position of OFDM symbol l in the subframe for SCS configuration μ is given by:

[0145]

[0146] Table 6: Supported transmission parameters

[0147] μ <![CDATA[Δf=2 μ ·15[kHz]]]> Cyclic prefix 0 15 normal 1 30 normal 2 60 Normal, Extended 3 120 normal 4 240 normal

[0148] Multiple OFDM parameters are supported, as given in Table 6, where Δf is SCS, and where μ and CP for BWP are obtained from high-level parameters subcarrierSpacing and cyclicPrefix, respectively. In Table 1, normal CP refers to 4.7 microseconds (μs) (or 5.2μs) and a CP duration of seven symbols / slots, and extended CP refers to 16.67μs and a CP duration of 6 symbols / slots.

[0149] In various embodiments, the digital baseband circuit 510 includes or implements a RIM-RS detection circuit, wherein the digital baseband circuit 510 monitors (or attempts to detect) one or more RIM-RS candidates in one or more (pre-)configured RIM-RS monitoring opportunities. The RIM-RS monitoring opportunities may be based on Figure 4 The RIM-RS time and frequency resource allocation 400, the previously discussed RIM-RS resource mapping implementation, and / or the previously discussed RIM-RS configuration implementation.

[0150] The communication circuit 500 also includes a transmit (Tx) circuit 515 and a receive (Rx) circuit 520. The Tx circuit 515 is configured to convert a digital baseband signal into an analog signal for transmission by the RF circuit 525. To this end, in one embodiment, the Tx circuit 515 includes various components such as a digital-to-analog converter (DAC), an analog baseband circuit, an up-conversion circuit, and a filtering and amplification circuit. Additionally or alternatively, the Tx circuit 515 may include a digital transmission circuit and an output circuit.

[0151] The Rx circuit 520 is configured to convert the analog signal received by the RF circuit 525 into a digital baseband signal to be provided to the digital baseband circuit 510. To this end, in one embodiment, the Rx circuit 520 includes one or more instances of parallel receive circuits and / or combined receive circuits. Examples of parallel receive circuits and combined receive circuits may include intermediate frequency (IF) down-conversion circuits, IF processing circuits, baseband down-conversion circuits, baseband processing circuits, and analog-to-digital converter (ADC) circuits.

[0152] The communication circuit 500 also includes a radio frequency (RF) circuit 525 to communicate with a wireless network through a non-solid medium using modulated electromagnetic radiation. The RF circuit 525 includes a receive signal path, which may include circuits for converting an analog RF signal (e.g., an existing or received modulated waveform) into a digital baseband signal to be provided to the digital baseband circuit 510 via the Rx circuit 520. The RF circuit 525 also includes a transmit signal path, which may include circuits configured to convert a digital baseband signal provided by the digital baseband circuit 510 via the Tx circuit 515 into an analog RF signal (e.g., a modulated waveform) to be amplified and transmitted via the antenna array 530.

[0153] In various embodiments, assume that in a subframe starting at t=0, the RIM-RS modulation (e.g., provided by RF circuitry 525) and up-conversion to carrier frequency f0 (e.g., provided by Tx circuitry 515) of a complex-valued OFDM baseband signal for antenna port p, SCS configuration μ, and OFDM symbol l is given by: where f0 RIM It is the configuration reference point of RIM-RS.

[0154] RF circuit 525 may include one or more examples of radio frequency link circuits, which may include one or more filters, power amplifiers, low noise amplifiers, programmable phase shifters, and power supplies (not shown). RF circuit 525 may also include power combining and distribution circuits. Power combining and distribution circuits may work bidirectionally so that the same physical circuit may be configured to work as a power divider when the device is transmitting and work as a power combiner when the device is receiving. In some embodiments, power synthesis and distribution circuits may include fully or partially independent circuits to perform power distribution when the device is transmitting and perform power synthesis when the device is receiving. Power synthesis and distribution circuits may include passive circuits including one or more bidirectional power dividers / synthesizers arranged in a tree shape. In some embodiments, power synthesis and distribution circuits may include active circuits containing amplifier circuits.

[0155] The communication circuit 500 also includes an antenna array 530. The antenna array 530 includes one or more antenna elements. The antenna array 530 may be a plurality of microstrip antennas or printed antennas fabricated on the surface of one or more printed circuit boards. The antenna array 530 may be formed as a patch of metal foil of various shapes (e.g., a patch antenna) and may be coupled to the RF circuit 525 using a metal transmission line or the like.

[0156] Fig. 6A , Figure 6B and Figure 7 1 and 2. Exemplary processes 600A, 600B, and 700 are shown, respectively, according to various embodiments. For illustrative purposes, various operations of processes 600A and 600B are described as being performed by Figure 1 UE 101 or its elements are performed, and process 700 is described as being performed by Figure 1 In some embodiments, the process 600A, the process 600B, and the process 700 may be embodied as one or more computer-readable storage media including program codes, instructions, or other similar computer program products (or data to create a computer program product), which will cause a computing device (e.g., UE 101 or RAN node 111) to perform electronic operations and / or perform operations related to Fig. 6A , Figure 6B and Figure 7 A specific sequence or flow of actions is described. Fig. 6A , Figure 6B and Figure 7 Specific examples and operation sequences are shown, but the order of operations depicted should not be understood as limiting the scope of the embodiments in any way. Rather, the operations depicted may be reordered, divided into additional operations, combined, and / or omitted entirely while remaining within the spirit and scope of the present disclosure.

[0157] FIG. 6 illustrates an example DM-RS configuration process 600A and process 600B according to various embodiments. Process 600A begins at operation 605, where the baseband circuitry of UE 101 determines one or more DM-RS port groups to be used for channel estimation based on the received DCI. At operation 610, the baseband circuitry of UE 101 performs channel estimation using one or more configured DM-RS ports belonging to the one or more DM-RS port groups. Process 600B begins at operation 615, where the baseband circuitry of UE 101 obtains corresponding DCI from each of a plurality of TRPs via RF circuitry and interface circuitry therebetween. At operation 620, the baseband circuitry of UE 101 determines one or more DM-RS port groups for each TRP based on the corresponding DCI received from each TRP. At operation 625, the baseband circuitry of UE 101 performs channel estimation using one or more configured DM-RS ports belonging to corresponding ports in the one or more DM-RS port groups.

[0158] Figure 7 An example DM-RS configuration process 700 is shown according to various embodiments. Process 700 begins at operation 705, where a TRP (e.g., RAN node 111) generates an RRC message to include a DM-RS configuration, the DM-RS configuration including a plurality of DM-RS port groups. At operation 710, the TRP transmits the RRC message to UE 101. At operation 715, the TRP generates a DCI to indicate one or more DM-RS port groups from the plurality of configured DM-RS port groups, and at operation 720, the TRP transmits the DCI to UE 101 to activate the one or more DM-RS port groups for channel estimation purposes.

[0159] Below are some non-limiting examples. The following examples relate to additional embodiments, and the details in the examples can be used anywhere in one or more embodiments previously discussed. Any of the following examples can be combined with any other example or any embodiment discussed herein.

[0160] Example A01 includes a method comprising: determining, by a baseband circuit, one or more demodulation reference signal (DM-RS) port groups to be used for channel estimation based on received downlink control information (DCI); and performing channel estimation by the baseband circuit using one or more configured DM-RS ports belonging to the one or more DM-RS port groups.

[0161] Example A02 includes a method according to Example A01 and / or some other examples herein, wherein the DCI is a single DCI for scheduling one or more corresponding physical downlink shared channels (PDSCHs) from multiple transmission reception points (TRPs) in a single DCI multiple TRP transmission scheme.

[0162] Example A03 includes a method according to Example A02 and / or some other examples herein, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group in the one or more DM-RS port groups belong to the same code division multiplexing (CDM) group.

[0163] Example A04 includes a method according to Example A02 and / or some other examples herein, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group in the one or more DM-RS port groups belong to different CDM groups.

[0164] Example A05 includes a method according to Examples A02 to A04 and / or some other examples herein, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group in the one or more DM-RS port groups are quasi-co-located in space.

[0165] Example A06 includes a method according to Examples A02 to A05 and / or some other examples herein, wherein each DM-RS port group in a plurality of configured DM-RS port groups corresponds to a separate transmission from a corresponding TRP in a plurality of TRPs, the plurality of configured DM-RS port groups include the one or more DM-RS port groups, and the method includes: implicitly determining, by the baseband circuit, a multiple-input multiple-output (MIMO) layer arriving from the corresponding TRP based on the DM-RS port group indicated by the DCI.

[0166] Example A07 includes a method according to Examples A02 to A05 and / or some other examples herein, wherein at least two of a plurality of configured DM-RS port groups correspond to the same TRP, the plurality of configured DM-RS port groups include the one or more DM-RS port groups, and the method further includes: determining, by the baseband circuit, quasi co-site (QCL) information for each of the at least two DM-RS port groups based on the received DCI.

[0167] Example A08 includes a method according to Example A07 and / or some other examples herein, wherein the method further includes: determining, by the baseband circuit, the QCL information for each of the at least two DM-RS port groups based on a corresponding transmission configuration indicator (TCI) field in the DCI or based on a single TCI field in the DCI.

[0168] Example A09 includes a method according to Example A08 and / or some other examples herein, wherein each of the multiple configured DM-RS port groups is associated with a TCI state that is different from at least one other DM-RS port group in the multiple configured DM-RS port groups.

[0169] Example A10 includes a method according to Examples A02 to A09 and / or some other examples herein, wherein the method further includes: determining, by the baseband circuit based on a received radio resource control (RRC) message, a plurality of configured DM-RS port groups including the one or more DM-RS port groups, wherein the DCI will activate the use of the one or more DM-RS port groups from the plurality of configured DM-RS port groups.

[0170] Example A11 includes a method according to Example A10 and / or some other examples herein, wherein each of the multiple configured DM-RS port groups corresponds to a separate transmission from a corresponding TRP from a plurality of TRPs, and the method further includes: determining, by the baseband circuit based on the RRC message, an identity of each TRP from the multiple TRPs from which a separate MIMO layer is provided.

[0171] Example A12 includes a method according to Examples A10 to A11 and / or some other examples herein, wherein each of the multiple configured DM-RS port groups is associated with a different cell identifier (ID) or a different scrambling code ID for initializing a DM-RS pseudo-random sequence.

[0172] Example A13 includes the method of Examples A10 to A12 and / or some other examples, wherein the separate CDM groups indicated by the RRC message are associated with different cell IDs.

[0173] Example A14 includes a method according to Example A01 and / or some other examples herein, wherein the DCI schedules corresponding PDSCH transmissions in a multiple DCI multiple TRP transmission scheme.

[0174] Example A15 includes a method according to Example A14 and / or some other examples herein, wherein the DCI is received from a single TRP among multiple TRPs in the multiple DCI multiple TRP transmission schemes via a physical downlink control channel (PDCCH), the one or more DM-RS port groups correspond to the single TRP, and the PDCCH and the DCI are associated with a TCI state.

[0175] Example A16 includes a method according to Examples A14 to A15 and / or some other examples herein, wherein each TRP in the multiple DCI multi-TRP transmission schemes uses the same DM-RS configuration type, number of front-loaded symbols, and number and position of additional DM-RS symbols within a time slot.

[0176] Example A17 includes a method according to Example A16 and / or some other examples herein, wherein each TRP in the multiple DCI multiple TRP transmission schemes also uses the same DM-RS mapping type.

[0177] Example A18 includes a method according to Example A16 and / or some other examples herein, wherein the DM-RS mapping type used by each TRP in the multiple DCI multiple TRP transmissions has a different time domain duration, and the method further includes: the baseband circuit implicitly determines the presence of additional DM-RS symbols from each TRP based on the scheduling of the different time domain durations.

[0178] Example A19 includes a method according to Example A16 and / or some other examples herein, wherein each TRP in the multiple DCI multiple TRP transmission schemes also uses the same DM-RS configuration type and different PDSCH mapping types, and the additional DM-RS symbols and positions are different.

[0179] Example A20 includes a method according to Examples A14 to A19 and / or some other examples herein, wherein the one or more configured DM-RS ports are quasi-orthogonal to each other.

[0180] Example B01 includes a method performed by a user equipment (UE), the method comprising: receiving corresponding downlink control information (DCI) from each transmission reception point (TRP) in a plurality of TRPs; determining one or more demodulation reference signal (DM-RS) port groups for each TRP based on the corresponding DCI received from each TRP; and performing channel estimation using one or more configured DM-RS ports belonging to a corresponding one of the one or more DM-RS port groups.

[0181] Example B02 includes a method according to Example B01 and / or some other examples herein, wherein the corresponding DCI received from each of the multiple TRPs is associated with a different transmission configuration indicator (TCI) state.

[0182] Example B03 includes a method according to Examples B01 to B02 and / or some other examples herein, wherein the corresponding DCI indicates the same DM-RS configuration type, the same number of front-loaded symbols, and the same number and position of additional DM-RS symbols within a time slot for detecting a separate DM-RS transmitted from each TRP.

[0183] Example B04 includes a method according to Example B03 and / or some other examples herein, wherein the corresponding DCI further indicates the same DM-RS mapping type for the separate DM-RS.

[0184] Example B05 includes a method according to Examples B01 to B02 and / or some other examples herein, wherein the DM-RS mapping type used by each TRP has a different time domain duration, and the method includes: implicitly determining the presence of additional DM-RS symbols from each TRP based on the scheduling of the different time domain durations.

[0185] Example B06 includes a method according to Examples B01 to B02 and B05 and / or some other examples herein, wherein the corresponding DCIs indicate the same DM-RS configuration type, and at least one of the corresponding DCIs indicates a DM-RS mapping type that is different from other DCIs in the corresponding DCIs, and at least one of the corresponding DCIs indicates additional DM-RS symbols and positions that are different from other DCIs in the corresponding DCIs.

[0186] Example B07 includes a method according to Examples B01 to B06 and / or some other examples herein, wherein the one or more configured DM-RS ports are quasi-orthogonal to each other.

[0187] Example C01 includes a method to be performed by a radio access network (RAN) node, the method comprising: generating downlink control information (DCI) to indicate one or more demodulation reference signal (DM-RS) port groups, each of the one or more DM-RS port groups including one or more configured DM-RS ports to be used for channel estimation; transmitting the DCI to a user equipment (UE); and transmitting the DM-RS in time-frequency resources according to the one or more configured DM-RS ports.

[0188] Example C02 includes a method according to Example C01 and / or some other examples in this document, wherein the DCI schedules a corresponding physical downlink shared channel (PDSCH) transmission; and transmits the PDSCH transmission to the UE according to the scheduling indicated by the DCI.

[0189] Example C03 includes a method according to Example C02 and / or some other examples herein, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group among the one or more DM-RS port groups belong to the same code division multiplexing (CDM) group or to different CDM groups.

[0190] Example C04 includes a method according to Examples C02 to C03 and / or some other examples herein, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group in the one or more DM-RS port groups are quasi-co-located in space.

[0191] Example C05 includes a method according to Examples C02 to C04 and / or some other examples herein, wherein each of the one or more DM-RS port groups corresponds to a multiple-input multiple-output (MIMO) layer to be transmitted by a transmission reception point (TRP) of a plurality of TRPs, and the RAN node is a TRP among the plurality of TRPs.

[0192] Example C06 includes a method according to Examples C02 to C04 and / or some other examples herein, wherein the one or more DM-RS port groups correspond to corresponding MIMO layers to be transmitted by the same TRP, and the method includes: generating the DCI to include quasi-co-site (QCL) information for each DM-RS port group in the one or more DM-RS port groups or for each corresponding MIMO layer in the corresponding MIMO layers.

[0193] Example C07 includes a method according to Example C06 and / or some other examples herein, wherein the method includes: generating the DCI to include a transmission configuration indicator (TCI) field for corresponding QCL information or including a single TCI field for indicating the corresponding QCL information.

[0194] Example C08 includes a method according to Examples C02 to C09 and / or some other examples herein, wherein the method includes: generating a radio resource control (RRC) message to indicate a plurality of configured DM-RS port groups including the one or more DM-RS port groups; and transmitting the RRC message to the UE.

[0195] Example C09 includes a method according to Examples C01 to C08 and / or some other examples herein, wherein the method includes: generating the RRC message to indicate a cell identifier (ID) of each DM-RS port group in the one or more DM-RS port groups and a scrambling code ID for initializing a DM-RS pseudo-random sequence.

[0196] Example C10 includes the method of Examples C01-C09 and / or some other examples, wherein the separate CDM groups indicated by the RRC message are associated with different cell IDs.

[0197] Example C11 includes a method according to Examples C01 to C09 and / or some other examples herein, wherein the time-frequency resources for transmitting the DM-RS according to the one or more configured DM-RS ports are quasi-orthogonal to each other.

[0198] Example Z01 may include an apparatus comprising components for performing one or more elements of a method described or related to any of Examples A01 to A20, B01 to B07, C01 to C11, or any other method or process described herein.

[0199] Example Z02 may include one or more non-transitory computer-readable media, which include instructions that, when executed by one or more processors of an electronic device, cause the processors to perform one or more elements of a method described in or related to any of Examples A01 to A20, B01 to B07, C01 to C11, or any other method or process described herein.

[0200] Example Z03 may include a device comprising logic components, modules, or circuits for performing one or more elements of a method described or related to any of Examples A01 to A20, B01 to B07, C01 to C11, or any other method or process described herein.

[0201] Example Z04 may include methods, techniques, or processes described or related to any of Examples A01 to A20, B01 to B07, C01 to C11, or parts or some thereof.

[0202] Example Z05 may include a device comprising: one or more processors and one or more computer-readable media, wherein the one or more computer-readable media include instructions that, when executed by the one or more processors, cause the one or more processors to perform a method, technique, or process, or portion thereof, described in or related to any one of Examples A01 to A20, B01 to B07, C01 to C11.

[0203] Example Z06 may include a signal or part or some thereof as described or related to any of Examples A01 to A20, B01 to B07, C01 to C11.

[0204] Example Z07 may include a datagram, packet, frame, segment, protocol data unit (PDU) or message as described or associated with any of Examples A01 to A20, B01 to B07, C01 to C11, or part or some thereof, or otherwise described in the present disclosure.

[0205] Example Z08 may include a signal encoded with data as described or associated with any of Examples A01 to A20, B01 to B07, C01 to C11, or a portion or some thereof, or otherwise described in the present disclosure.

[0206] Example Z09 may include a signal encoded with a datagram, packet, frame, segment, protocol data unit (PDU) or message as described or associated with any of Examples A01 to A20, B01 to B07, C01 to C11, or a portion or some thereof, or otherwise described in the present disclosure.

[0207] Example Z10 may include an electromagnetic signal carrying computer-readable instructions, wherein execution of the computer-readable instructions by one or more processors will cause the one or more processors to perform a method, technique, or process, or portion thereof, described in or related to any of Examples A01 to A20, B01 to B07, C01 to C11.

[0208] Example Z11 may include a computer program comprising instructions, wherein execution of the program by a processing element will cause the processing element to perform a method, technique, or process, or a portion thereof, described in or related to any one of Examples A01 to A20, B01 to B07, C01 to C11.

[0209] Example Z12 may include a signal in a wireless network as shown and described herein. Example Z13 may include a method of communicating in a wireless network as shown and described herein. Example Z14 may include a system for providing wireless communication as shown and described herein. Example Z15 may include an apparatus for providing wireless communication as shown and described herein.

[0210] Unless otherwise expressly stated, any of the above examples may be combined with any other example (or combination of examples). The terms used herein are only intended to describe specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "a / an" and "the" are intended to include plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the terms "include" and / or "comprise" are used in this specification to specify the presence of stated features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or their grouping. For the purposes of this disclosure, the phrase "A and / or B" means (A), (B) or (A and B). For the purposes of this disclosure, the phrase "A, B and / or C" refers to (A), (B), (C), (A and B), (A and C), (B and C) or (A, B and C). The description may use the phrase "in one embodiment" or "in some embodiments", which may each refer to one or more of the same or different embodiments. In addition, the terms "comprising," "including," "having," and the like used with the embodiments of the present disclosure are synonymous. The term "coupled" (or variations thereof) may mean that two or more elements are in direct physical or electrical contact with each other, may mean that two or more elements are in indirect contact with each other but still cooperate or interact with each other, and / or may mean that one or more other elements are coupled or connected between the elements said to be coupled to each other. The term "communicatively coupled" may mean that two or more elements can contact each other by means of communication, including through a wire or other interconnect connection, through a wireless communication channel or link, and the like.

[0211] The foregoing description provides an illustration and description of various exemplary embodiments, but is not intended to be exhaustive or to limit the scope of the embodiments to the precise form disclosed. In view of the above teachings, modifications and variations are possible, or modifications and variations can be obtained from the practice of various embodiments. Where specific details are set forth for the purpose of describing the exemplary embodiments of the present disclosure, it should be apparent to those skilled in the art that the present disclosure can be practiced without these specific details or with variations of these specific details. However, it should be understood that there is no intention to limit the concepts of the present disclosure to the specific form disclosed, but on the contrary, it is intended to cover all modifications, equivalents, and alternatives consistent with the present disclosure and the appended claims.

Claims

1. A system on chip (SoC) to be implemented in a user equipment (UE), the SoC comprising: Interface circuit; and A baseband circuit, the baseband circuit is coupled to the interface circuit, the interface circuit is used to communicatively couple the baseband circuit to a radio frequency (RF) circuit, and the baseband circuit is used to: determining one or more demodulation reference signal (DM-RS) port groups to be used for channel estimation based on downlink control information (DCI) received via the RF circuit, wherein the one or more DM-RS port groups are activated based on the DCI and are selected from a plurality of DM-RS port groups configured based on a DM-RS configuration, the DM-RS configuration being transmitted to the UE using a radio resource control (RRC) message; as well as Channel estimation is performed using one or more configured and activated DM-RS ports belonging to the one or more DM-RS port groups.

2. The SoC according to claim 1, wherein the DCI is a single DCI for scheduling one or more corresponding physical downlink shared channels (PDSCH) from multiple TRPs in a single DCI multiple transmission receiving point (TRP) transmission scheme.

3. The SoC according to claim 2, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group among the one or more DM-RS port groups belong to the same code division multiplexing CDM group or belong to different CDM groups, and wherein the one or more configured DM-RS ports belonging to the same DM-RS port group among the one or more DM-RS port groups are quasi-co-located in space.

4. The SoC of claim 3, wherein each of a plurality of configured DM-RS port groups corresponds to a separate transmission from a corresponding TRP in a plurality of TRPs, the plurality of configured DM-RS port groups comprising the one or more DM-RS port groups, and the baseband circuitry is further configured to: The multiple-input multiple-output MIMO layer arriving from the corresponding TRP is implicitly determined based on the DM-RS port group indicated by the DCI.

5. The SoC of claim 3, wherein at least two of a plurality of configured DM-RS port groups correspond to the same TRP, the plurality of configured DM-RS port groups including the one or more DM-RS port groups, and the baseband circuit is further configured to: Quasi co-located QCL information for each of the at least two DM-RS port groups is determined based on the received DCI.

6. The SoC according to claim 5, wherein the baseband circuit is further configured to: The QCL information of each of the at least two DM-RS port groups is determined based on a corresponding transmission configuration indicator (TCI) field in the DCI or based on a single TCI field in the DCI.

7. The SoC of claim 6, wherein each of the plurality of configured DM-RS port groups is associated with a TCI state that is different from at least one other DM-RS port group of the plurality of configured DM-RS port groups.

8. The SoC according to any one of claims 2 to 7, wherein the baseband circuit is further configured to: The plurality of DM-RS port groups including the one or more DM-RS port groups are determined based on the RRC message.

9. The SoC of claim 8, wherein each of the plurality of configured DM-RS port groups corresponds to a separate transmission from a corresponding TRP of a plurality of TRPs, and the baseband circuitry is further configured to: An identity of each TRP among the multiple TRPs from which a separate MIMO layer is provided is determined based on the RRC message, wherein each DM-RS port group among the multiple configured DM-RS port groups is associated with a different cell identification ID or a different scrambling code ID for initialization of a DM-RS pseudo-random sequence, and wherein the separate CDM groups indicated by the RRC message are associated with different cell IDs.

10. The SoC according to claim 1, wherein the DCI will schedule corresponding PDSCH transmission in multiple DCI multiple TRP transmission schemes, wherein the DCI is received from a single TRP among multiple TRPs in the multiple DCI multiple TRP transmission schemes via a physical downlink control channel PDCCH, the one or more DM-RS port groups correspond to the single TRP, and the PDCCH and the DCI are associated with a TCI state.

11. The SoC of claim 10, wherein each TRP in the multiple DCI multiple TRP transmission schemes uses the same DM-RS configuration type, number of front-loaded symbols, and number and position of additional DM-RS symbols within a time slot.

12. The SoC of claim 11, wherein each TRP in the multiple DCI multiple TRP transmission schemes also uses the same DM-RS mapping type.

13. The SoC according to claim 11, wherein the DM-RS mapping type used by each TRP in the plurality of DCI multiple TRP transmissions has a different time domain duration, and the baseband circuit is further configured to: The presence of additional DM-RS symbols from each TRP is implicitly determined based on the scheduling of the different time domain durations.

14. The SoC according to claim 11, wherein each TRP in the multiple DCI multiple TRP transmission schemes also uses the same DM-RS configuration type and a different PDSCH mapping type, and the additional DM-RS symbols and positions are different.

15. The SoC according to any one of claims 10 to 14, wherein the one or more configured DM-RS ports are quasi-orthogonal to each other.

16. One or more computer readable media CRM, the CRM comprising instructions, which when executed by one or more processors of a user equipment UE, will cause the UE to: Receiving corresponding downlink control information DCI from each of the plurality of transmission reception points TRP, One or more demodulation reference signal (DM-RS) port groups for each TRP are determined based on the corresponding DCI received from each TRP, wherein: The one or more DM-RS port groups of each TRP are activated based on the corresponding DCI and are selected from a plurality of DM-RS port groups configured based on a DM-RS configuration, the DM-RS configuration being transmitted to the UE using a radio resource control RRC message; as well as Channel estimation is performed using one or more configured and activated DM-RS ports belonging to a corresponding one of the one or more DM-RS port groups.

17. One or more CRMs according to claim 16, wherein the corresponding DCI received from each TRP of the multiple TRPs is associated with different transmission configuration indicator TCI states, wherein the corresponding DCI indicates the same DM-RS configuration type within a time slot, the same number of front-loaded symbols, and the same number and position of additional DM-RS symbols for detecting a separate DM-RS transmitted from each TRP.

18. The one or more CRMs of claim 17, wherein the corresponding DCI further indicates the same DM-RS mapping type for the separate DM-RS.

19. The one or more CRMs of claim 17, wherein the DM-RS mapping type used by each TRP has a different time domain duration, and execution of the instructions causes the UE to: The presence of additional DM-RS symbols from each TRP is implicitly determined based on the scheduling of the different time domain durations, wherein the corresponding DCIs indicate the same DM-RS configuration type, and at least one of the corresponding DCIs indicates a DM-RS mapping type different from other DCIs in the corresponding DCIs, and at least one of the corresponding DCIs indicates additional DM-RS symbols and positions different from other DCIs in the corresponding DCIs.

20. The one or more CRMs of any one of claims 16 to 19, wherein the one or more configured DM-RS ports are quasi-orthogonal to each other.

21. An apparatus to be implemented in a Radio Access Network (RAN) node, the apparatus comprising: a processor component configured to generate downlink control information DCI to indicate one or more demodulation reference signal DM-RS port groups, each of the one or more DM-RS port groups comprising one or more configured DM-RS ports to be used for channel estimation, wherein the one or more DM-RS port groups are activated based on the DCI and are selected from a plurality of DM-RS port groups configured based on a DM-RS configuration, the DM-RS configuration being transmitted using a radio resource control RRC message; and A radio frequency (RF) component is used to transmit the DCI to a user equipment (UE), and to transmit a DM-RS in a time-frequency resource according to the one or more configured DM-RS ports, wherein the time-frequency resources used to transmit the DM-RS according to the one or more configured DM-RS ports are orthogonal or quasi-orthogonal to each other.

22. The apparatus of claim 21, wherein the DCI is to schedule a corresponding physical downlink shared channel (PDSCH) transmission, and the RF component is to transmit the PDSCH transmission to the UE according to the schedule indicated by the DCI.

23. An apparatus according to claim 22, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group among the one or more DM-RS port groups belong to the same code division multiplexing CDM group or belong to different CDM groups, wherein the one or more configured DM-RS ports belonging to the same DM-RS port group among the one or more DM-RS port groups are quasi-co-located in space, and wherein each DM-RS port group among the one or more DM-RS port groups corresponds to a multiple-input multiple-output MIMO layer to be transmitted by a TRP among multiple transmission reception points TRPs, and the RAN node is a TRP among the multiple TRPs.

24. The apparatus of claim 23, wherein the one or more DM-RS port groups correspond to respective MIMO layers to be transmitted by the same TRP, and the processor component is further configured to: generating the DCI to include quasi-co-site QCL information for each DM-RS port group in the one or more DM-RS port groups or for each MIMO layer in the corresponding MIMO layers; and The DCI is generated to include a transmission configuration indicator TCI field for corresponding QCL information or to include a single TCI field to indicate the corresponding QCL information.

25. The device according to any one of claims 21 to 24, wherein: The processor component is used to generate the RRC message to indicate a plurality of configured DM-RS port groups including the one or more DM-RS port groups, and to indicate a cell identification ID for each DM-RS port group in the one or more DM-RS port groups and a scrambling code ID initialized for a DM-RS pseudo-random sequence, wherein separate CDM groups indicated by the RRC message are associated with different cell IDs; and The RF component is used to transmit the RRC message to the UE.

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