Sounding reference signal resource indicator design for 8 transmit antenna uplink operation

Abstract

The present disclosure relates to techniques for configuring (8) transmit antenna uplink operation in a wireless communication system. A wireless link may be established between a wireless device and a cellular base station. The wireless device may perform sounding reference signal transmission on each of (8) sounding reference signal resources, wherein each resource is associated with a transmit antenna port. The wireless device may receive, from the cellular base station, an indication of a transmit antenna port uplink configuration to be used (8), which may include a sounding reference signal resource indicator. The wireless device may perform uplink communications with the cellular base station using the transmit antenna port configuration (8).

Description

Technical Field

[0001] The present application relates to wireless communications, and more particularly to systems, apparatuses, and methods for configuring 8-transmit antenna uplink operations in a wireless communication system.

[0002] Related technical description

[0003] The use of wireless communication systems is growing rapidly. In recent years, wireless devices such as smart phones and tablet computers have become increasingly sophisticated. In addition to supporting phone calls, many mobile devices (i.e., user equipment devices or UEs) now also provide access to the Internet, email, text messaging, and navigation using a global positioning system (GPS), and are capable of operating sophisticated applications that utilize these capabilities. In addition, there are many different wireless communication technologies and wireless communication standards. Some examples of wireless communication standards include GSM, UMTS (e.g., associated with WCDMA or TD-SCDMA air interfaces), LTE, Advanced LTE (LTE-A), NR, HSPA, 3GPP2 CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), IEEE 802.11 (WLAN or Wi-Fi), Bluetooth, and the like. TM wait.

[0004] The introduction of an ever-increasing number of features and functionalities in wireless communication devices has also created a continuing need for improved wireless communications and improved wireless communication devices. In particular, it is important to ensure the accuracy of signals transmitted and received by user equipment (UE) devices (e.g., by wireless devices such as cellular phones, base stations, and relay stations used in wireless cellular communications). In addition, increasing the functionality of UE devices may put a great strain on the battery life of UE devices. Therefore, it is also very important to reduce the power requirements in UE device designs while allowing UE devices to maintain good transmission and reception capabilities to improve communications. Therefore, improvements are desired in this area. Summary of the invention

[0005] Embodiments of apparatus, systems, and methods for configuring eight-transmit antenna uplink operations in a wireless communication system are presented herein.

[0006] According to the techniques described herein, it is possible to use a sounding reference signal resource indicator to configure an 8-transmit antenna port configuration for a wireless device for non-codebook based uplink communication with a cellular base station. For such operation, there may be several possible sounding reference signal resource indicator design options, including an option that allows selection of any possible combination of sounding reference signal resources, and an option that allows selection of a subset of possible combinations of sounding reference signal resources with lower signaling overhead.

[0007] The present invention also describes a technique for configuring an 8-transmit antenna port configuration for a wireless device for codebook-based uplink communication with a cellular base station using one or more transmit precoding matrix indicators. For such operation, there may be several possible transmit precoding matrix indicator design options, including a non-coherent codebook option that allows selection of any possible combination of sounding reference signal ports, and an option that allows selection of a subset of possible combinations of sounding reference signal ports with lower signaling overhead. Options for non-coherent codebook and partially coherent codebook designs are also described, which utilize multiple transmit precoding matrix indicators, each of which is configured to indicate a precoding matrix for a lower transmit antenna port count, and use these smaller precoding matrices to construct a precoding matrix for 8-transmit antenna port operation.

[0008] It should be noted that the techniques described herein may be implemented in and / or used with a number of different types of devices, including but not limited to base stations, access points, cellular telephones, portable media players, tablet computers, wearable devices, unmanned aerial vehicles, unmanned flight controllers, automobiles and / or motor vehicles, and various other computing devices.

[0009] This summary is intended to provide a brief overview of some of the topics described in this document. Therefore, it should be understood that the above features are only examples and should not be construed as narrowing the scope or essence of the topics described herein in any way. Other features, aspects, and advantages of the topics described herein will become apparent through the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] A better understanding of the present subject matter may be obtained when the following detailed description of various embodiments is considered in conjunction with the following drawings, in which:

[0011] Figure 1 illustrates an exemplary (and simplified) wireless communication system according to some embodiments;

[0012] Figure 2 illustrates an exemplary base station in communication with an exemplary wireless user equipment (UE) device according to some embodiments;

[0013] Figure 3 illustrates an exemplary block diagram of a UE according to some embodiments;

[0014] Figure 4 illustrates an exemplary block diagram of a base station according to some embodiments;

[0015] Figure 5is a flow chart illustrating aspects of an exemplary possible method for configuring 8 transmit antenna uplink operation in a wireless communication system according to some embodiments;

[0016] Figure 6 is a table illustrating possible SRI bit widths corresponding to a possible maximum number of uplink transmission layers according to some embodiments;

[0017] Figure 7 is a table illustrating possible SRI values ​​and corresponding selected SRS resources for a rank threshold based SRI design method according to some embodiments;

[0018] Figure 8 illustrates possible precoding matrices that may be indicated by TPMI values ​​for a rank threshold based TPMI design method according to some embodiments;

[0019] Fig. 9 illustrates aspects of one possible example scenario in which a TPMI design approach is used, wherein multiple TPMIs for a lower number of transmit antenna ports are provided for non-coherent codebook uplink operation, according to some embodiments;

[0020] FIG. 10A to FIG. 10D illustrates exemplary aspects of various possible partially coherent transmit antenna configurations according to some embodiments;

[0021] Fig.11 illustrates aspects of one possible example scenario in which the TPMI design method is used, according to some embodiments, wherein four 2-antenna-port TPMIs are provided for partially coherent codebook uplink operation; and

[0022] Fig.12 Aspects of one possible example scenario in which the TPMI design approach is used, according to some embodiments, are illustrated, where two 4-antenna-port TPMIs are provided for partially coherent codebook uplink operation.

[0023] Although the features described herein are susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and described in detail herein. However, it should be understood that the drawings and detailed description thereof are not intended to be limited to the specific forms disclosed, but on the contrary, are intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as defined by the appended claims. DETAILED DESCRIPTION

[0024] Acronyms

[0025] Various acronyms are used throughout this disclosure. Definitions of the most commonly used acronyms that may appear throughout this disclosure are provided below:

[0026] UE: User Equipment

[0027] RF: Radio Frequency

[0028] BS: Base Station

[0029] GSM: Global System for Mobile Communications

[0030] UMTS: Universal Mobile Telecommunications System

[0031] LTE: Long Term Evolution

[0032] NR: New Radio

[0033] TX: Send

[0034] RX: Receive

[0035] RAT: Radio Access Technology

[0036] TRP: Transmit Receive Point

[0037] RRC: Radio Resource Control

[0038] MAC: Media Access Control

[0039] DCI: Downlink Control Information

[0040] PUSCH: Physical Uplink Shared Channel

[0041] SRS: Sounding Reference Signal

[0042] SRI: SRS Resource Indicator

[0043] TPMI: Transmit Precoding Matrix Indicator

[0044] the term

[0045] The following is a glossary of terms that will appear in this disclosure:

[0046] Memory medium—any of various types of non-transitory memory devices or storage devices. The term "memory medium" is intended to include installation media, such as CD-ROM, floppy disk, or tape devices; computer system memory or random access memory, such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory, such as flash memory, magnetic media, such as hard disk drives or optical storage devices; registers or other similar types of memory elements, etc. The memory medium may also include other types of non-transitory memory or combinations thereof. In addition, the memory medium may be located in a first computer system executing a program, or may be located in a different second computer system connected to the first computer system via a network such as the Internet. In the latter example, the second computer system may provide program instructions to the first computer system for execution. The term "memory medium" may include two or more memory media, which may reside in different locations in different computer systems connected, for example, via a network. The memory medium may store program instructions (e.g., embodied as a computer program) that may be executed by one or more processors.

[0047] Carrier Media—Memory media as described above, as well as physical transmission media such as a bus, network, and / or other physical transmission media that convey signals such as electrical, electromagnetic, or digital signals.

[0048] Computer system (or computer)—any of various types of computing or processing systems, including a personal computer system (PC), a mainframe computer system, a workstation, a network appliance, an Internet appliance, a personal digital assistant (PDA), a television system, a grid computing system, or other devices or combinations of devices. In general, the term "computer system" may be broadly defined as any device (or combination of devices) that includes at least one processor that executes instructions from a memory medium.

[0049] User Equipment (UE) (or "UE device") - any of various types of computer systems or devices that are mobile or portable and that perform wireless communications. Examples of UE devices include mobile phones or smart phones (e.g., iPhone TM , based on Android TM phones), tablet computers (e.g., iPad TM 、Samsung Galaxy TM ), portable gaming devices (e.g., Nintendo DS TM , PlayStation Portable TM 、Gameboy Advance TM , iPhoneTM ), wearable devices (e.g., smart watches, smart glasses), laptops, PDAs, portable Internet devices, music players, data storage devices, other handheld devices, automobiles and / or motor vehicles, unmanned aerial vehicles (UAVs) (e.g., drones), UAV controllers (UACs), etc. In general, the term "UE" or "UE device" can be broadly defined to cover any electronic device, computing device, and / or telecommunication device (or a combination of these devices) that is easily transportable by a user and capable of wireless communication.

[0050] Wireless Device—Any of various types of computer systems or devices that perform wireless communications. A wireless device may be portable (or mobile), or may be stationary or fixed at a location. A UE is an example of a wireless device.

[0051] Communication device - any of various types of computer systems or devices that perform communication, where the communication may be wired or wireless. A communication device may be portable (or mobile), or may be stationary or fixed at a location. A wireless device is an example of a communication device. A UE is another example of a communication device.

[0052] Base Station (BS)—The term "base station" has the full breadth of its ordinary meaning and includes at least a wireless communication station installed at a fixed location and used to communicate as part of a wireless telephone system or radio system.

[0053] Processing element (or processor) - refers to various elements or combinations of elements that are capable of performing functions in a device (e.g., a user equipment device or a cellular network device). Processing elements may include, for example, processors and associated memory, portions or circuits of individual processor cores, entire processor cores, processor arrays, circuits such as ASICs (application specific integrated circuits), programmable hardware elements such as field programmable gate arrays (FPGAs), and any of the above combinations.

[0054] Wi-Fi—The term "Wi-Fi" has the full scope of its ordinary meaning and includes at least a wireless communication network or RAT that is served by wireless LAN (WLAN) access points and provides connectivity to the Internet through these access points. Most modern Wi-Fi networks (or WLAN networks) are based on the IEEE 802.11 standard and are marketed under the name "Wi-Fi". Wi-Fi (WLAN) networks are distinct from cellular networks.

[0055] Automatically—refers to an action or operation being performed by a computer system (e.g., software executed by a computer system) or a device (e.g., a circuit, a programmable hardware element, an ASIC, etc.) without the action or operation being directly specified or performed by a user input. Thus, the term "automatically" is in contrast to an operation being manually performed or specified by a user, where the user provides input to directly perform the operation. An automatic process may be initiated by input provided by a user, but subsequent actions performed "automatically" are not specified by the user, i.e., are not performed "manually," where the user specifies each action to be performed. For example, a user filling out an electronic form by selecting each field and providing input specifying information (e.g., by typing in information, selecting checkboxes, radio selections, etc.) is manually filling out the form, even though the computer system must update the form in response to the user action. The form may be automatically filled out by a computer system, where the computer system (e.g., software executed on the computer system) analyzes the fields of the form and fills out the form without any user input specifying the answers to the fields. As indicated above, a user may invoke automatic filling out of a form, but not participate in the actual filling out of the form (e.g., the user does not manually specify the answers to the fields but rather they are automatically completed). This specification provides various examples of operations that are automatically performed in response to actions that a user has taken.

[0056] Configured to—Various components may be described as being “configured to” perform one or more tasks. In such contexts, “configured to” is a broad statement that generally means “having a structure” that performs one or more tasks during operation. Thus, a component may be configured to perform a task even when the component is not currently performing the task (e.g., a collection of electrical conductors may be configured to electrically connect a module to another module even when the two modules are not connected). In some contexts, “configured to” may be a broad statement that generally means “having a circuit” that performs one or more tasks during operation. Thus, a component may be configured to perform a task even when the component is not currently turned on. Typically, circuits that form a structure corresponding to “configured to” may include hardware circuits.

[0057] For ease of description, various components may be described as performing one or more tasks. Such descriptions should be interpreted to include the phrase "configured to". The statement that a component is configured to perform one or more tasks is expressly intended not to invoke the interpretation of 35 U.S.C. § 112, section 6, for that component.

[0058] Figure 1 and Figure 2 -Exemplary Communication System

[0059] Figure 1 An exemplary (and simplified) wireless communication system that can implement various aspects of the present disclosure according to some embodiments is illustrated. Note that Figure 1The system is only one example of a possible system, and the embodiments may be implemented in any of a variety of systems as desired.

[0060] As shown, the exemplary wireless communication system includes a base station 102, which communicates with one or more (e.g., any number) user equipment 106A, 106B, etc. to 106N via a transmission medium. Each user equipment may be referred to herein as a "user equipment" (UE) or UE device. Therefore, user equipment 106 is referred to as a UE or UE device.

[0061] The base station 102 may be a base transceiver station (BTS) or a cell site, and may include hardware and / or software that implements wireless communication with UEs 106A to 106N. If the base station 102 is implemented in the context of LTE, it may be referred to as an "eNodeB" or "eNB". If the base station 102 is implemented in the context of 5G NR, it may alternatively be referred to as a "gNodeB" or "gNB". The base station 102 may also be equipped to communicate with a network 100 (e.g., a core network of a cellular service provider, a telecommunications network such as a public switched telephone network (PSTN), and / or the Internet, and various possible networks). Therefore, the base station 102 may facilitate communication between user devices and / or between user devices and the network 100. The communication area (or coverage area) of a base station may be referred to as a "cell". Also as used herein, with respect to a UE, sometimes a base station may be considered to represent a network in consideration of the uplink and downlink communications of the UE. Therefore, a UE communicating with one or more base stations in a network may also be understood as a UE communicating with a network.

[0062] It should be noted that, at least in some 3GPP NR contexts, the base station (gNB) functionality may be split between a centralized unit (CU) and a distributed unit (DU). At least according to some embodiments, in such a network deployment context, the base station 102 shown may support the functionality of either or both of the CU or DU. In some instances, the base station 102 may be configured to act as an integrated access and backhaul (IAB) donor (e.g., including IAB donor CU and / or IAB donor DU functionality). In some instances, the base station 102 may be configured to act as an IAB node (e.g., including IAB mobile terminal (MT) and IAB-DU functionality). Other specific implementations are also possible.

[0063] The base station 102 and the user equipment may be configured to communicate over a transmission medium using any of a variety of radio access technologies (RATs), also referred to as wireless communication technologies or telecommunication standards, such as GSM, UMTS (WCDMA), LTE, Advanced LTE (LTE-A), LAA / LTE-U, 5G NR, 3GPP2 CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), Wi-Fi, etc.

[0064] Base station 102 and other similar base stations operating according to the same or different cellular communication standards may thus be provided as one or more cell networks that may provide continuous or nearly continuous overlapping service to UE 106 and similar devices over a geographic area via one or more cellular communication standards.

[0065] Note that UE 106 is capable of communicating using multiple wireless communication standards. For example, UE 106 may be configured to communicate using either or both of the 3GPP cellular communication standard or the 3GPP2 cellular communication standard. In some embodiments, UE 106 may be configured to perform techniques for performing 8 transmit antenna uplink operations in a wireless communication system, such as according to the various methods described herein. UE 106 may also be configured or may alternatively be configured to use WLAN, Bluetooth, or other wireless communication standards. TM , one or more global navigation satellite systems (GNSS, such as GPS or GLONASS), one and / or more mobile television broadcast standards (e.g., ATSC-M / H), etc. Other combinations of wireless communication standards (including more than two wireless communication standards) are also possible.

[0066] Figure 2An exemplary user device 106 (e.g., one of devices 106A to 106N) communicating with a base station 102 according to some embodiments is illustrated. UE 106 may be a device with wireless network connectivity, such as a mobile phone, a handheld device, a wearable device, a computer or tablet computer, an unmanned aerial vehicle (UAV), an unmanned flight controller (UAC), a car, or almost any type of wireless device. UE 106 may include a processor (processing element) configured to execute program instructions stored in a memory. UE 106 may perform any method implementation in the method implementation scheme described herein by executing such stored instructions. Alternatively or in addition, UE 106 may include a programmable hardware element, such as an FPGA (field programmable gate array), an integrated circuit, and / or any of various other possible hardware components configured to perform (e.g., individually or in combination) any method implementation in the method implementation scheme described herein or any part of any method implementation in the method implementation scheme described herein. UE 106 may be configured to communicate using any of a plurality of wireless communication protocols. For example, UE 106 may be configured to communicate using two or more of CDMA2000, LTE, LTE-A, 5G NR, WLAN, or GNSS. Other combinations of wireless communication standards are also possible.

[0067] UE 106 may include one or more antennas for communicating using one or more wireless communication protocols according to one or more RAT standards. In some embodiments, UE 106 may share one or more parts of a receive chain and / or a transmit chain between multiple wireless communication standards. The shared radio component may include a single antenna, or may include multiple antennas (e.g., for a multiple-input, multiple-output or "MIMO" antenna system) for performing wireless communications. Typically, the radio component may include any combination of a baseband processor, an analog RF signal processing circuit (e.g., including filters, mixers, oscillators, amplifiers, etc.), or a digital processing circuit (e.g., for digital modulation and other digital processing). Similarly, the radio component may use the aforementioned hardware to implement one or more receive chains and transmit chains. For example, UE 106 may share one or more parts of a receive chain and / or a transmit chain between multiple wireless communication technologies such as those discussed above.

[0068] In some embodiments, UE 106 may include any number of antennas and may be configured to use the antennas to send and / or receive directional wireless signals (e.g., beams). Similarly, BS 102 may also include any number of antennas and may be configured to use the antennas to send and / or receive directional wireless signals (e.g., beams). In order to receive and / or send such directional signals, the antennas of UE 106 and / or BS 102 may be configured to apply different "weights" to different antennas. The process of applying these different weights may be referred to as "precoding".

[0069] In some embodiments, the UE 106 may include a separate transmit chain and / or receive chain (e.g., including separate antennas and other radio components) for each wireless communication protocol with which it is configured to communicate. As another possibility, the UE 106 may include one or more radio components shared between multiple wireless communication protocols, and one or more radio components used uniquely by a single wireless communication protocol. For example, the UE 106 may include shared radio components for communicating using any of LTE or CDMA2000 1xRTT (or LTE or NR, or LTE or GSM), and shared radio components for communicating using Wi-Fi and Bluetooth. TM Each of the independent radio components for communication. Other configurations are also possible.

[0070] Figure 3 - Block diagram of an exemplary UE device

[0071] Figure 3A block diagram of an exemplary UE 106 according to some embodiments is illustrated. As shown, the UE 106 may include a system on chip (SOC) 300, which may include parts for various purposes. For example, as shown, the SOC 300 may include a processor 302 that can execute program instructions for the UE 106, and a display circuit 304 that can perform graphics processing and provide display signals to a display 360. The SOC 300 may also include a sensor circuit 370, which may include a component for sensing or measuring any of various possible characteristics or parameters of the UE 106. For example, the sensor circuit 370 may include a motion sensing circuit that is configured to detect the motion of the UE 106, for example, using a gyroscope, an accelerometer, and / or any of various other motion sensing components. As another possibility, the sensor circuit 370 may include one or more temperature sensing components, which are used, for example, to measure the temperature of each of one or more antenna panels and / or other components of the UE 106. Any of a variety of other possible types of sensor circuits may also or alternatively be included in the UE 106, as desired. The processor 302 may also be coupled to a memory management unit (MMU) 340, which may be configured to receive addresses from the processor 302 and translate those addresses into locations in memory (e.g., memory 306, read-only memory (ROM) 350, NAND flash memory 310) and / or other circuits or devices, such as display circuit 304, radio 330, connector I / F 320, and / or display 360. The MMU 340 may be configured to perform memory protection and page table translation or setup. In some embodiments, the MMU 340 may be included as part of the processor 302.

[0072] As shown, SOC 300 may be coupled to various other circuits of UE 106. For example, UE 106 may include various types of memory (e.g., including NAND flash memory 310), connector interface 320 (e.g., for coupling to a computer system, a docking station, a charging station, etc.), display 360, and wireless communication circuitry 330 (e.g., for LTE, LTE-A, NR, CDMA2000, Bluetooth TM, Wi-Fi, GPS, etc.). The UE device 106 may include or be coupled to at least one antenna (e.g., 335a), and may include multiple antennas (e.g., illustrated by antennas 335a and 335b) for performing wireless communications with base stations and / or other devices. Antennas 335a and 335b are shown by way of example, and the UE device 106 may include fewer or more antennas. In general, one or more antennas are collectively referred to as antennas 335. For example, the UE device 106 may use antenna 335 with the aid of radio circuitry 330 to perform wireless communications. The communication circuit may include multiple receive chains and / or multiple transmit chains for receiving and / or transmitting multiple spatial streams, such as in a multiple-input multiple-output (MIMO) configuration. As mentioned above, in some embodiments, the UE may be configured to perform wireless communications using multiple wireless communication standards.

[0073] UE 106 may include hardware and software components for implementing methods for UE 106 to perform techniques for performing 8 transmit antenna uplink operations in a wireless communication system, such as those further described later herein. The processor 302 of the UE device 106 may be configured to implement part or all of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). In other embodiments, the processor 302 may be configured as a programmable hardware element, such as an FPGA (field programmable gate array) or as an ASIC (application-specific integrated circuit). In addition, as Figure 3 As shown, the processor 302 can be coupled to other components and / or can interoperate with other components to perform techniques for performing 8-transmit antenna uplink operations in a wireless communication system according to various embodiments disclosed herein. The processor 302 can also implement various other applications and / or end-user applications running on the UE 106.

[0074] In some embodiments, radio 330 may include a separate controller dedicated to controlling communications for each corresponding RAT standard. Figure 3 As shown, the radio component 330 may include a Wi-Fi controller 352, a cellular controller (e.g., an LTE and / or LTE-A controller) 354, and a Bluetooth TM Controller 356, and in at least some embodiments, one or more or all of these controllers may be implemented as respective integrated circuits (referred to as ICs or chips) that communicate with each other and with SOC 300 (and more specifically, with processor 302). For example, Wi-Fi controller 352 may communicate with cellular controller 354 via a cell-ISM link or WCI interface, and / or Bluetooth controller 355 may communicate with cellular controller 354 via a cell-ISM link or WCI interface. TMThe controller 356 may communicate with the cellular controller 354 via a cell-ISM link, etc. Although three separate controllers are illustrated within the radio 330, other embodiments may be implemented in the UE device 106 having fewer or more similar controllers for various different RATs.

[0075] Additionally, embodiments are contemplated in which the controller may implement functionality associated with multiple radio access technologies. For example, according to some embodiments, in addition to hardware and / or software components for performing cellular communications, the cellular controller 354 may also include hardware and / or software components for performing one or more activities associated with Wi-Fi, such as Wi-Fi preamble detection, and / or generation and transmission of Wi-Fi physical layer preamble signals.

[0076] Figure 4 - Block diagram of an exemplary base station

[0077] Figure 4 1 illustrates a block diagram of an exemplary base station 102 according to some embodiments. Note that Figure 4 The base station of is only one example of a possible base station. As shown, the base station 102 may include a processor 404 that may execute program instructions for the base station 102. The processor 404 may also be coupled to a memory management unit (MMU) 440 or other circuit or device, which may be configured to receive addresses from the processor 404 and convert these addresses to locations in memory (e.g., memory 460 and read-only memory (ROM) 450).

[0078] Base station 102 may include at least one network port 470. Network port 470 may be configured to couple to a telephone network and provide access to the telephone network described above. Figure 1 and Figure 2 The network port 470 may be configured to couple to a plurality of devices such as the UE device 106 to the telephone network described in the foregoing. The network port 470 (or an additional network port) may also or alternatively be configured to couple to a cellular network, such as a core network of a cellular service provider. The core network may provide mobility-related services and / or other services to a plurality of devices such as the UE device 106. In some cases, the network port 470 may be coupled to the telephone network via the core network, and / or the core network may provide the telephone network (e.g., in other UE devices served by the cellular service provider).

[0079] In some embodiments, base station 102 may be a next generation base station, e.g., a 5G New Radio (5G NR) base station, or "gNB". In such embodiments, base station 102 may be connected to a legacy evolved packet core (EPC) network and / or to an NR core (NRC) network. Furthermore, base station 102 may be considered a 5G NR cell and may include one or more transmit and receive points (TRPs). Furthermore, a UE capable of operating in accordance with 5G NR may be connected to one or more TRPs within one or more gNBs.

[0080] The base station 102 may include at least one antenna 434 and possibly multiple antennas. The antenna 434 may be configured to operate as a wireless transceiver and may also be configured to communicate with the UE device 106 via the radio component 430. The antenna 434 communicates with the radio component 430 via a communication chain 432. The communication chain 432 may be a receive chain, a transmit chain, or both. The radio component 430 may be designed to communicate via various wireless telecommunication standards, including but not limited to 5G NR, 5G NR SAT, LTE, LTE-A, GSM, UMTS, CDMA2000, Wi-Fi, etc.

[0081] The base station 102 may be configured to perform wireless communications using multiple wireless communication standards. In some cases, the base station 102 may include multiple radio components that enable the base station 102 to communicate according to multiple wireless communication technologies. For example, as one possibility, the base station 102 may include an LTE radio component for performing communications according to LTE and a 5G NR radio component for performing communications according to 5G NR. In this case, the base station 102 may be able to operate as both an LTE base station and a 5GNR base station. As another possibility, the base station 102 may include a multimode radio component that can perform communications according to any one of a plurality of wireless communication technologies (e.g., 5G NR and Wi-Fi, 5G NR SAT and Wi-Fi, LTE and Wi-Fi, LTE and UMTS, LTE and CDMA2000, UMTS and GSM, etc.).

[0082] As further described later herein, BS 102 may include hardware and software components for implementing or supporting a specific implementation of the features described herein. The processor 404 of the base station 102 may be configured to implement and / or support a specific implementation of part or all of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively, the processor 404 may be configured as a programmable hardware element such as an FPGA (field programmable gate array), or as an ASIC (application-specific integrated circuit) or a combination thereof. In the case of certain RATs (e.g., Wi-Fi), the base station 102 may be designed as an access point (AP), in which case the network port 470 may be implemented to provide access to a wide area network and / or one or more local area networks, for example, it may include at least one Ethernet port, and the radio component 430 may be designed to communicate according to the Wi-Fi standard.

[0083] Furthermore, as described herein, processor 404 may include one or more processing elements. Thus, processor 404 may include one or more integrated circuits (ICs) configured to perform the functions of processor 404. Furthermore, each integrated circuit may include circuits (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of one or more processors 404.

[0084] Additionally, as described herein, radio 430 may include one or more processing elements. Thus, radio 430 may include one or more integrated circuits (ICs) configured to perform the functions of radio 430. Additionally, each integrated circuit may include circuits (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of radio 430.

[0085] Reference signal

[0086] A wireless device (such as a user equipment) may be configured to perform various tasks including using reference signals (RS) provided by one or more cellular base stations. For example, initial access and beam measurements of the wireless device may be performed based at least in part on synchronization signal blocks (SSBs) provided by one or more cells provided by one or more cellular base stations within the communication range of the wireless device. Another type of reference signal commonly provided in a cellular communication system may include a channel state information (CSI) RS. Various types of CSI-RS may be provided for tracking (e.g., for time and frequency offset tracking), beam management (e.g., CSI-RS configured with repetitions to help determine one or more beams for uplink and / or downlink communications), and / or channel measurement (e.g., CSI-RS configured in a resource set for measuring the quality of a downlink channel and reporting information related to the quality measurement to a base station), as well as various possibilities. For example, in the case where the CSI-RS is used for CSI acquisition, the UE may periodically perform channel measurements and transmit channel state information (CSI) to the BS. The base station may then receive and use the channel state information during communication with the wireless device to determine adjustments to various parameters. In particular, the BS may use the received channel state information to adjust the coding of its downlink transmissions to improve downlink channel quality.

[0087] In many cellular communication systems, a base station may periodically transmit some or all such reference signals (or pilot signals), such as SSB and / or CSI-RS. In some cases, aperiodic reference signals (e.g., aperiodic reference signals for aperiodic CSI reporting) may also or alternatively be provided.

[0088] As a detailed example, at least according to some embodiments, in the 3GPP NR cellular communication standard, the channel state information fed back from the UE based on the CSI-RS for CSI acquisition may include one or more of a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), a CSI-RS resource indicator (CRI), a SSBRI (SS / PBCH resource block indicator, and a layer indicator (LI).

[0089] Channel quality information may be provided to the base station for link adaptation, for example, to provide guidance on which modulation and coding scheme (MCS) the base station should use when sending data. For example, when the downlink channel communication quality between the base station and the UE is determined to be high, the UE may feedback a high CQI value, which may cause the base station to send data using a relatively high modulation order and / or a low channel coding rate. For another example, when the downlink channel communication quality between the base station and the UE is determined to be low, the UE may feedback a low CQI value, which may cause the base station to send data using a relatively low modulation order and / or a high channel coding rate.

[0090] The PMI feedback may include preferred precoding matrix information and may be provided to the base station to indicate which MIMO precoding scheme the base station should use. In other words, the UE may measure the quality of the downlink MIMO channel between the base station and the UE based on the pilot signal received on the channel, and may recommend which MIMO precoding the desired base station applies through PMI feedback. In some cellular systems, the PMI configuration is represented in matrix form, which provides linear MIMO precoding. The base station and the UE may share a codebook consisting of multiple precoding matrices, wherein each MIMO precoding matrix in the codebook may have a unique index. Therefore, as part of the channel state information fed back by the UE, the PMI may include an index (or possibly multiple indexes) corresponding to the most preferred MIMO precoding matrix (or multiple matrices) in the codebook. This may enable the UE to minimize the amount of feedback information. Therefore, at least according to some embodiments, the PMI may indicate which precoding matrix from the codebook should be used for transmission to the UE.

[0091] For example, when the base station and UE have multiple antennas, the rank indicator information (RI feedback) may indicate the number of transmission layers that the UE determines can be supported by the channel, which can achieve multi-layer transmission through spatial multiplexing. RI and PMI together may allow the base station to know which precoding needs to be applied to which layer, for example, depending on the number of transmission layers.

[0092] In some cellular systems, the PMI codebook is defined based on the number of transmission layers. In other words, for R layer transmission, N N codebooks can be defined. t ×R matrix (for example, where R represents the number of layers, N t denotes the number of transmitter antenna ports, and N denotes the size of the codebook). In such a scenario, the number of transmission layers (R) may conform to the rank value of the precoding matrix (N t ×R matrix), and thus R in this context may be referred to as a “rank indicator (RI)”.

[0093] Thus, the channel state information may include an assigned rank (e.g., a rank indicator or RI). For example, a MIMO-enabled UE communicating with a BS may include four receiver chains, e.g., may include four antennas. The BS may also include four or more antennas to implement MIMO communication (e.g., 4×4 MIMO). Thus, the UE is able to simultaneously receive up to four (or more) signals (e.g., layers) from the BS. Layer-to-antenna mapping may be applied, e.g., each layer may be mapped to any number of antenna ports (e.g., antennas). Each antenna port may transmit and / or receive information associated with one or more layers. The rank may include multiple bits and may indicate the number of signals that the BS may transmit to the UE in an upcoming time period (e.g., during an upcoming transmit time interval or TTI). For example, an indication of rank 4 may indicate that the BS will transmit 4 signals to the UE. As one possibility, the length of the RI may be two bits (e.g., because two bits are sufficient to distinguish 4 different rank values). Note that other numbers and / or configurations of antennas (e.g., at either or both of the UE or BS) and / or other numbers of data layers are also possible according to various embodiments.

[0094] At least in some systems, uplink MIMO is also possible. At least as one possibility, codebook-based uplink MIMO can be performed, in which a transmit precoding matrix indicator (TPMI) is used to indicate a precoding matrix for use by the wireless device for uplink transmission. Codebook-based uplink MIMO may include non-coherent codebook operation (e.g., when there is no coherence between different uplink / transmit antennas), partially coherent codebook operation (e.g., when there is coherence between certain antenna elements but no coherence between different coherent antenna groups), or fully coherent codebook operation (e.g., when there is coherence between all antenna elements). For example, in scenarios where the downlink channel and the uplink channel are understood to be reciprocal, non-codebook-based uplink MIMO is also possible. In such non-codebook based uplink MIMO, the wireless device may perform sounding reference signal transmission using different configurations on different sounding reference signal resources (e.g., using different transmit antenna ports), and a sounding reference signal resource indicator may be used to indicate for which sounding reference signal resources the associated configuration for the uplink transmission configuration should be included.

[0095] Figures 5 to 8 Transmit antenna uplink operation configuration

[0096] As previously described herein, at least some cellular communication technologies may be capable of supporting, for example, multiple-input multiple-output (MIMO) uplink communications utilizing up to four uplink transmit antenna ports. In at least some cases, supporting uplink communications using multiple antenna ports may have the potential to increase throughput, provide additional robustness for challenging channel conditions, and / or provide any of a variety of other possible benefits, but may have a higher cost (e.g., in terms of price, power consumption, form factor, complexity, etc.) compared to designs and communication technologies with fewer antenna counts. For at least some devices, the benefits of supporting uplink operations utilizing a relatively large number (e.g., more than four) of transmit antenna ports may outweigh the costs. Therefore, in at least some cases, it may be useful to provide techniques for supporting such operations in a cellular communication system.

[0097] Therefore, it may be beneficial to specify techniques for supporting configuration 8 transmit antenna uplink operation. To illustrate a set of such possible techniques, Figure 5 is a flow chart illustrating a method for configuring eight transmit antenna uplink operations in a wireless communication system according to at least some embodiments.

[0098] Figure 5 Aspects of the methods of can be implemented by a wireless device, for example, in conjunction with one or more cellular base stations (such as UE 106 and BS 102 shown and described with respect to various figures herein), or more generally, as desired, in conjunction with any of the computer circuits, systems, devices, elements or components, etc. shown in the above figures. For example, a processor (and / or other hardware) of such a device can be configured to cause the device to perform any combination of the illustrated method elements and / or other method elements.

[0099] It is noted that although the present invention is described in a manner involving the use of communication techniques and / or features associated with 3GPP and / or NR specification documents, Figure 5 However, this description is not intended to limit the present disclosure and may be used in any suitable wireless communication system as needed. Figure 5 In various embodiments, some of the elements of the method shown may be performed simultaneously in an order different from that shown, may be replaced by other method elements, or may be omitted. Additional method elements may also be performed as needed. As shown in the figure, Figure 5 The method can be operated as follows.

[0100] In 502, the wireless device may establish a wireless link with a cellular base station. According to some embodiments, the wireless link may include a cellular link according to 5G NR. For example, the wireless device may establish a session with an AMF entity of a cellular network through one or more gNBs that provide radio access to the cellular network. As another possibility, the wireless link may include a cellular link according to LTE. For example, the wireless device may establish a session with a mobility management entity of a cellular network through an eNB that provides radio access to the cellular network. According to various embodiments, other types of cellular links are also possible, and the cellular network may also or alternatively operate according to another cellular communication technology (e.g., UMTS, CDMA2000, GSM, etc.).

[0101] Establishing a wireless link may include establishing an RRC connection with a serving cellular base station according to at least some embodiments. Establishing a first RRC connection may include configuring various parameters for communication between the wireless device and the cellular base station, establishing environmental information of the wireless device, and / or any of a variety of other possible features, for example, involving establishing an air interface of the wireless device for cellular communication with a cellular network associated with the cellular base station. After establishing the RRC connection, the wireless device may operate in an RRC connected state. In some instances, the RRC connection may also be released (e.g., after a certain period of inactivity relative to data communication), in which case the wireless device may operate in an RRC idle state or an RRC inactive state. In some instances, the wireless device may perform a handover (e.g., when in an RRC connected mode) or a cell reselection (e.g., when in an RRC idle mode or an RRC inactive mode) to a new serving cell, for example, due to wireless device mobility, changes in wireless medium conditions, and / or any of a variety of other possible reasons.

[0102] According to at least some embodiments, a wireless device may establish multiple wireless links according to a multi-TRP configuration, for example, with multiple TRPs of a cellular network. In this case, the wireless device may be configured (e.g., via RRC signaling) with one or more transmit control indicators (TCIs), for example, which may correspond to various beams that may be used to communicate with the TRPs. In addition, there may be situations where one or more configured TCI states may be activated by a medium access control (MAC) control element (CE) of the wireless device at a particular time.

[0103] In at least some instances, establishing the wireless link may include the wireless device providing capability information of the wireless device. Such capability information may include information related to any of a plurality of types of wireless device capabilities.

[0104] At 504, the wireless device may receive from a cellular base station an indication of a TX antenna port configuration to be used to perform uplink communications. According to at least some embodiments, the configuration may be for more than 4 TX antenna ports (e.g., as one possibility, for 8 TX antenna ports). In at least some embodiments, the indication may be provided in downlink control information (DCI) that schedules uplink communications.

[0105] The cellular base station may provide multiple possible types of indications to configure the wireless device for uplink communication. As one possibility, for a non-codebook configuration, the wireless device may perform SRS transmission on each of a plurality of (e.g., as one possibility, 8) sounding reference signal (SRS) resources, wherein each of the SRS resources is associated with a TX antenna port of the wireless device, and the cellular base station may provide an SRS resource indicator (SRI) to the wireless device to indicate which of the available TX antenna ports to use (e.g., by indicating the SRS resources associated with the TX antenna ports).

[0106] For such a non-codebook approach, there may be multiple possible SRI designs that can support indications of 8TX antenna port (and / or other number of TX antenna ports) uplink configurations. As one possibility, the SRI may have a bit width equal to the number of uplink TX antenna ports of the wireless device (e.g., such that for an 8TX antenna port uplink configuration, the SRI may have a bit width of 8 bits). In such a case, it is possible that each bit in the SRI is associated with an SRS resource, and the cellular base station may indicate which TX antenna ports are used for the uplink configuration by setting the bits of the SRI to 1 for the SRS resources associated with the selected TX antenna port.

[0107] As another SRI design approach, the SRI bit width may not be fixed, and may instead depend at least in part on how many uplink transmit layers are configured to be scheduled by the cellular base station for the wireless device for non-codebook based uplink operation (e.g., an upper limit or maximum number of configurations of uplink transmit layers for the wireless device). In at least some instances, such as if the number of configurable uplink transmit layers is less than the number of uplink TX antenna ports available at the wireless device, such an approach may potentially reduce the bit width (and thus potentially reduce the signaling overhead of configuring the uplink TX antenna port configurations for the wireless device). For example, in such a scenario, the total number of possible uplink TX antenna port combinations may be less than or equal to the number that can be represented using fewer bits than the number of uplink TX antenna ports, in which case a correspondingly shorter SRI bit width may still be able to represent all possible uplink TX antenna port combinations that meet the maximum number of configurations of uplink transmit layers for the wireless device.

[0108] The number of uplink transmission layers for non-codebook based uplink operation that can be scheduled by the cellular base station for the wireless device may be determined based on wireless device capability information provided from the wireless device to the cellular base station (e.g., indicating the number of uplink transmission layers for non-codebook based uplink operation supported by the wireless device), radio resource control (RRC) configuration information provided from the cellular base station to the wireless device indicating the maximum number of uplink transmission layers configured to be scheduled by the cellular base station, or a combination thereof and various possibilities. According to various embodiments, if the wireless device reports such capability information, such capability information may be provided at any of various possible granularity levels (e.g., per wireless device, per component carrier, per frequency band, per frequency band combination, per component carrier per frequency band per frequency band combination, etc.). If different capabilities are reported for different scenarios (e.g., as one possibility, for different component carriers in the same frequency band for each frequency band combination), it may be possible to always use the minimum reporting number, or always use the maximum reporting number, or the RRC configuration information may be used to determine which reporting number to use on a more dynamic basis.

[0109] As another option for SRI design (which can reduce the bit width required to signal TX antenna port configurations for a relatively large number of uplink TX antenna ports), it is possible to implement a method that utilizes a rank threshold in a manner that limits the number of possible combinations of SRS resources that can be selected for rank values ​​equal to or greater than a rank threshold. In such a scenario, an uplink rank threshold can be determined for a wireless link between a wireless device and a cellular base station. As various possibilities, the uplink rank threshold can be predetermined (e.g., in a 3GPP technical specification) or configured by the network (e.g., using RRC or medium access control (MAC) control element (CE) signaling). For rank values ​​below the uplink rank threshold (e.g., the number of uplink transmission layers), the SRI can be designed to support the selection of any combination of SRS resources from the SRS resources on which the wireless device performs SRS transmission.

[0110] For rank values ​​equal to or greater than an uplink rank threshold, the SRI may be designed to support selection of a subset of possible combinations of SRS resources on which the wireless device performs SRS transmission. For example, for each possible number N of uplink transmission layers, it may be the case that the SRI supports selection of any combination of SRS resources from the first M SRS resources on which the wireless device performs SRS transmission O, where N≤M≤O. In such an example, it may be the case that the value of M is selected by the network, for example depending on N (e.g., M=N, M=N+1, etc.), as a way to effectively manage the balance between the flexibility of selecting uplink TX configurations from a greater number of possible numbers of choices and the higher signaling overhead to support such greater flexibility. It should be noted that other techniques for limiting a subset of possible combinations of SRS resources for rank values ​​equal to or greater than the uplink rank threshold are also possible.

[0111] In some instances, as a possible alternative to using a single rank threshold, it is possible to implement a method of utilizing two complementary subsets of uplink rank values ​​in a manner that limits the number of possible combinations of SRS resources that can be selected for a rank value in one of the subsets of uplink rank values. In such a scenario, a first subset of uplink rank values ​​may include one or more uplink ranks, and a second subset of uplink rank values ​​includes uplink ranks not included in the first subset. As various possibilities, the subsets may be predetermined (e.g., in a 3GPP technical specification) or configured by the network (e.g., using RRC or MAC CE signaling). In some instances, as a possibility, the first subset may include rank values ​​with relatively few possible combinations of SRS resources, such as rank 1 and a rank equal to the number of TX antenna ports of the wireless device. Other ways of configuring rank subsets are also possible.

[0112] For rank values ​​in the first subset, the SRI may be designed to support selecting any combination of SRS resources from the SRS resources on which the wireless device performs SRS transmission. For rank values ​​in the second subset, the SRI may be designed to support selecting a subset of possible combinations of SRS resources on which the wireless device performs SRS transmission. For example, for each possible number N of uplink transmission layers, it may be the case that the SRI supports selecting any combination of SRS resources from the first M SRS resources of the SRS resources on which the wireless device performs SRS transmission O, where N≤M≤O. In such an example, it may be the case that the value of M is selected by the network, for example depending on N (e.g., M=N, M=N+1, etc.), as a way to effectively manage the balance between the flexibility of selecting uplink TX configurations from a greater number of possible numbers of choices and the higher signaling overhead to support such greater flexibility. It should be noted that other techniques for limiting the subset of possible combinations of SRS resources for rank values ​​in the second subset are also possible.

[0113] As another SRI design option, it may be possible to configure a custom SRI to SRS resource selection mapping. For example, if such a technique is supported, it may be the case that a cellular base station may provide SRI to SRS resource selection mapping information for the wireless device to the wireless device. The mapping information may indicate which SRI values ​​indicate which SRS resources are selected. Such information may be used by the cellular base station to select an SRI to provide to the wireless device to indicate the selected SRS resource for uplink communication. Such information may also be stored by the wireless device and used to identify which SRS resource (and corresponding TX antenna port) the wireless device selects for uplink communication when the wireless device receives an SRI for uplink communication. In at least some embodiments, the wireless device may provide capability information to the cellular base station to indicate whether the wireless device supports such a custom SRI to SRS resource selection mapping, and / or indicate a memory limit for the wireless device to store such SRI to SRS resource selection mapping information (e.g., as a possibility, as a maximum number of SRI to SRS resource selection mapping entries supported by the wireless device). According to at least some embodiments, if the wireless device indicates limited capability for storing such SRI to SRS resource selection mapping information, it may be the case that the cellular base station limits the SRI to SRS resource selection mapping information for the wireless device to within the capabilities of the wireless device.

[0114] In some embodiments, it is possible that the indication of the TX antenna port configuration for uplink communication from the cellular base station includes one or more transmit precoding matrix indicators (TPMIs). For example, one or more TPMIs can be used to provide a wireless device with a codebook-based TX antenna port configuration, potentially including a non-coherent codebook-based TX antenna port configuration, or a partially coherent codebook-based TX antenna port configuration.

[0115] As one possibility, for a non-coherent codebook based TX antenna port configuration, the TPMI may have a bit width equal to the number of uplink TX antenna ports of the wireless device (e.g., such that for an 8 TX antenna port uplink configuration, the TPMI may have a bit width of 8 bits). In such a case, it is possible that each bit in the TPMI is associated with a TX antenna port (or associated with an SRS resource, which in turn is associated with a TX antenna port), and the cellular base station may indicate which TX antenna ports are used for the uplink configuration by setting the bits of the TPMI to 1 for the selected TX antenna port / SRS resource.

[0116] As another possibility, a rank threshold-based approach designed for TPMI can be used for certain TX antenna port counts (e.g., higher TX antenna port counts, such as 8 TX antenna ports). Similar to the rank threshold-based approach designed for SRI, such an approach has the potential to reduce the bit width required to signal the TX antenna port configuration for a relatively large number of uplink TX antenna ports, although scheduling flexibility may be sacrificed. In such a scenario, an uplink rank threshold may be determined for a wireless link between a wireless device and a cellular base station. As various possibilities, the uplink rank threshold may be predetermined (e.g., in a 3GPP technical specification) or configured by the network (e.g., using RRC or MAC CE signaling). For rank values ​​below the uplink rank threshold, the TPMI may be designed to support the selection of any combination of TX antenna ports / SRS resources. For rank values ​​equal to or greater than the uplink rank threshold, the TPMI may be designed to support the selection of a subset of possible combinations of TX antenna ports / SRS resources. For example, for an 8TX antenna port wireless device, for each possible number N of uplink transmit layers, it may be that the TPMI supports selecting any combination of TX antenna ports / SRS resources from the first MTX antenna ports / SRS resources, where N≤M≤8. In such an example, it may be that the value of M is selected by the network, for example depending on N (e.g., M=N, M=N+1, etc.), as a way to effectively manage the balance between the flexibility of selecting uplink TX configurations from a greater number of possible choices and the higher signaling overhead to support such greater flexibility. It is noted that other techniques for limiting a subset of possible combinations of TX antenna ports / SRS resources for rank values ​​equal to or greater than the uplink rank threshold are also possible.

[0117] Methods designed for TPMI in which two rank subsets are used for certain TX antenna port counts (e.g., higher TX antenna port counts, such as 8 TX antenna ports) are also possible. Similar to rank subset-based methods designed for SRI, such methods have the potential to reduce the bit width required to signal TX antenna port configurations for a relatively large number of uplink TX antenna ports, although scheduling flexibility may be sacrificed. In such a scenario, a first subset of uplink rank values ​​may be determined for a wireless link between a wireless device and a cellular base station. As various possibilities, the first subset may be predetermined (e.g., in a 3GPP technical specification) or configured by the network (e.g., using RRC or MAC CE signaling). In some instances, as one possibility, the first subset may include rank values ​​with relatively few possible combinations of TX antenna ports, such as rank 1 and a rank equal to the number of TX antenna ports of the wireless device. Other ways of configuring rank subsets are also possible.

[0118] For rank values ​​in the first subset, the TPMI may be designed to support the selection of any combination of TX antenna ports / SRS resources. For rank values ​​in the second subset (which may include any rank value that is possible for a wireless device that is not in the first subset, at least according to some embodiments), the TPMI may be designed to support the selection of a subset of possible combinations of TX antenna ports / SRS resources. For example, for an 8TX antenna port wireless device, for each possible number N of uplink transmit layers, it is possible that the TPMI supports the selection of any combination of TX antenna ports / SRS resources from the first MTX antenna ports / SRS resources, where N≤M≤8. In such an example, it is possible that the value of M is selected by the network, for example depending on N (e.g., M=N, M=N+1, etc.), as a way to effectively manage the balance between the flexibility of selecting uplink TX configurations from a greater number of possible choices and the higher signaling overhead to support such greater flexibility. It should be noted that other techniques for limiting a subset of possible combinations of TX antenna ports / SRS resources for rank values ​​in the second subset are also possible.

[0119] As yet another possibility, by providing multiple TPMIs for a smaller number of TX antenna ports, it is possible to support a greater number of TX antenna ports for non-coherent codebook and / or partial codebook uplink operations of the wireless device. For example, for an 8TX antenna port non-coherent codebook uplink configuration, a cellular base station may provide two 4TX antenna port TPMIs. According to such a design, it may be the case that the uplink transmit layer splitting between TPMIs is performed in a fixed manner (e.g., performed as evenly as possible, where as one possibility, the previous The first TPMI indicates the number of PUSCH layers, and the remaining PUSCH layers are indicated by a second TPMI). As another possibility, it may be that the uplink transmit layer split between TPMIs may be flexibly determined by the network; for example, as one possibility, the network may indicate the total number of uplink transmit layers and the number of uplink transmit layers allocated to the first TPMI. Note that the number of uplink transmit layers for a TPMI may be limited to the number of TX antenna ports for the TPMI (e.g., for a 4TX antenna port TPMI, no more than 4 uplink transmit layers). A wireless device receiving multiple such TPMIs may construct a precoding matrix for uplink transmission based on the precoding matrices indicated by the multiple TPMIs; for example, each precoding matrix indicated by the indicated TPMI may be used to fill a corresponding portion of the precoding matrix for uplink transmission, wherein the remaining (e.g., non-diagonal) portion of the precoding matrix for uplink transmission is filled with zeros.

[0120] For a partially coherent codebook uplink configuration, it is possible to provide a TPMI for each coherent antenna group of a wireless device. For example, for an 8TX antenna port partially coherent codebook uplink configuration, a cellular base station may provide four 2TX antenna port TPMIs (e.g., for a wireless device with 4 coherent antenna groups, each of which has 2 antenna elements), where one TPMI in the 2TX antenna port TPMIs is associated with each coherent antenna group. Similarly, a cellular base station may provide two 4TX antenna port TPMIs (e.g., for a wireless device with 2 coherent antenna groups, each of which has 4 antenna elements), where one TPMI in the 4TX antenna port TPMIs is associated with each coherent antenna group.

[0121] According to such a design, it is possible that the uplink transmit layer splitting between TPMIs is performed in a fixed manner (e.g., performed as evenly as possible, where as one possibility, if the rank is divisible by the number of coherent antenna groups, each antenna group contains the same number of uplink transmit layers, and if the rank is not divisible by the number of coherent antenna groups, an additional uplink transmit layer is assigned to the coherent antenna group in a consecutive order to account for any additional uplink transmit layers). As another possibility, it is possible that the uplink transmit layer splitting between TPMIs can be flexibly determined by the network. Note again that the number of uplink transmit layers for a TPMI can be limited to the number of TX antenna ports for the TPMI (e.g., for a 4TX antenna port TPMI, no more than 4 uplink transmit layers). A wireless device receiving multiple such TPMIs may construct a precoding matrix for uplink transmission based on the precoding matrices indicated by the multiple TPMIs; for example, each precoding matrix indicated by the indicated TPMI may be used to fill a corresponding portion of the precoding matrix for uplink transmission, wherein the remaining (e.g., non-diagonal) portion of the precoding matrix for uplink transmission is filled with zeros.

[0122] In 506, the wireless device may perform uplink communications with the cellular base station using the TX antenna port uplink configuration. According to some embodiments, the uplink communications may include physical uplink shared channel (PUSCH) communications scheduled by the cellular base station using the same DCI that provides an indication of the TX antenna port uplink configuration. Thus, for example, for a scenario in which the wireless device is an 8TX antenna port wireless device, for example, according to any of the various SRI and / or TPMI design methods described herein or variations thereof, the wireless device may perform PUSCH transmissions to the cellular base station using the selected 8TX antenna port uplink configuration, and the selected 8TX antenna port uplink configuration may be a non-codebook, non-coherent codebook, or partially coherent codebook 8TX antenna port uplink configuration.

[0123] Thus, at least according to some embodiments, Figure 5 The method may be used to provide a framework by which a wireless device may be configured to utilize a greater number of transmit antennas than are currently supported to perform cellular uplink communications, which may allow, at least in some cases, greater diversity in wireless device types and possible use cases, among other possible benefits.

[0124] Figures 6 to 12 and additional information

[0125] Figures 6 to 12 This example shows that if necessary, you can combine Figure 5 However, it should be noted that Figures 6 to 12 The exemplary details illustrated in and described with respect to these figures are not intended to limit the disclosure as a whole: many variations and alternatives to the details provided below are possible and should be considered within the scope of the disclosure.

[0126] Cellular communication technology may support multiple modes for uplink multiple-input multiple-output (MIMO) operation. For example, 3GPP 5G NR may support codebook-based physical uplink shared channel (PUSCH) operation and non-codebook-based PUSCH operation. For codebook-based PUSCH operation, it is possible to indicate the precoding information and the number of layers by scheduling the "precoding information and number of layers" field in the downlink control information (DCI). At least according to some embodiments, existing possible precoding (e.g., transmit precoding matrix indicator (TPMI)) may be specified in 3GPP TS38.211v.17.2.0 and 3GPP TS 38.212v.17.2.0. For non-codebook-based PUSCH operation, the precoding and number of layers may be indicated by scheduling the sounding reference signal (SRS) resource indicator (SRI) field in the DCI.

[0127] In NR, for codebook-based uplink MIMO operation, NR may also support three different coherence modes. At least according to some embodiments, these modes may include non-coherent (e.g., codebookSubset = "nonCoherent"), partially coherent (e.g., codebookSubset = "partialAndNonCoherent"), and fully coherent (e.g., codebookSubset = "fullyandPartialandNonCoherent"). In existing NR operations, for uplink MIMO operation, it is possible to support up to 4 transmit (TX) antenna port operations and up to 4 layers of PUSCH.

[0128] For some devices (e.g., with fewer form factors, price points, power consumption, and / or other constraints), uplink operation with more than 4 TX antenna ports may be desired. To support such operation, it may be useful to provide techniques for configuring an uplink TX configuration for a wireless device for higher TX antenna port count operation (e.g., 8 TX antenna port operation and / or other TX antenna port counts).

[0129] Such techniques may include providing SRI design and / or TPMI design options for one or more of nonCodebook PUSCH operation, non-coherent codebook PUSCH operation, partially coherent codebook PUSCH operation, and / or fully coherent codebook PUSCH operation. Techniques for SRI design and TPMI design options for at least nonCodebook PUSCH operation, non-coherent codebook PUSCH operation, and partially coherent codebook PUSCH operation are described herein. For codebook-based PUSCH operation, a "precoding information and number of layers" field design modification that may be used in some instances is also described herein.

[0130] For 8TX nonCodebook uplink operation, it is possible to configure 8 SRS resources in the SRS-ResourceSet configuration information, where the usage parameter is set to "nonCodebook" so that each SRS resource is configured with one port. In the scheduling DCI, the SRI field can be used to indicate the number of layers (e.g., the number of selected SRS resources) and, for a given number of selected SRS resources, to identify which SRS resources are selected.

[0131] As an option for the SRI field design that can indicate such information, it is possible to use an 8-bit bitmap (e.g., for 8TX antenna port uplink operation, the bit width of SRI can be fixed to 8), where each bit of the bitmap is associated with an SRS resource, and if the bit associated with the SRS resource is set, this can indicate that the corresponding SRS resource is set. In such a scenario, SRI can be {S0, S1, S2, S3, S4, S5, S6, S7}, S i , i=0,1,…,7 indicates whether the i-th SRS resource is selected.

[0132] In some instances, for a given wireless device, the number of PUSCH layers that can be scheduled by the network may be limited. In such scenarios, at least in some cases, it may be possible to reduce the bit width of the SRI, such as if the bit width of the SRI is designed to depend on the maximum number of PUSCH layers that can be scheduled by the network. The maximum number of PUSCH layers that can be scheduled by the network (“L max”) may be determined based on the NR RRC configuration for the wireless device (e.g., in a parameter such as maxMIMO layers in PUSCH-ServingCellConfig) and / or based on a capability reported by the UE (e.g., a capability indication by the UE for the maximum number of PUSCH layers for non-codebook based operation supported by the serving cell), which may be reported per component carrier per feature set (per component carrier per band per band combination). In some examples, in the same band per band combination, if the UE reports multiple maximum numbers corresponding to different component carriers, it may be the case that the smallest reported maximum number of PUSCH layers is considered to be L max Alternatively, in the same band per band combination, if the UE reports multiple maximum numbers corresponding to different component carriers, it may be the case that the maximum reported maximum number of the PUSCH layer is considered to be L max .

[0133] As used when configuring L max One possibility to potentially limit the bit width of the SRI field is to specify or configure that the SRI may be used to indicate up to L of the 8 SRS resources for 8TX non-codebook PUSCH operation. max Any combination of SRS resources of SRS resources. In such a scenario, the bit width of SRI can be calculated as:

[0134]

[0135] in is the number of possible choices for selecting k candidate values ​​from 8 candidate values, and L max is the maximum number of uplink transmission layers configured to be scheduled by the cellular base station. Figure 6 is an example of using this method according to some embodiments corresponding to possible L max Table of possible SRI bit widths for values.

[0136] As another approach, it is possible to predetermine or configure a rank threshold (which may also be referred to as R) for a wireless device or more generally for a network or serving cell via RRC. th ). When the number of PUSCH layers is less than R th When the number of PUSCH layers is equal to or greater than R, it is possible that SRI can be used to select any combination of SRS resources from among the eight SRS resources. thFor the restricted subset, for each possible number N of PUSCH layers, it is possible that SRI can be used to select any combination of SRS resources from only the first M SRS resources out of the 8 SRS resources, where N≤M≤8. Note that it is possible to use a variant design where N≤M<8, in the special case that M=8 is allowed only when N=8, for example, because it may be the case that the number of possible combinations is meaningful only when M<8 is true. Figure 7 is exemplified in L max =8, R th TABLE 1 Table of possible SRI values ​​and corresponding selected SRS resources according to such an approach in an exemplary scenario where M = 2 and M = N.

[0137] As another approach, it is possible to predetermine or configure a subset of uplink rank values ​​for the wireless device or more generally for the network or serving cell via RRC. When the number of PUSCH layers is in the subset, it is possible that SRI can be used to select any combination of SRS resources from 8 SRS resources. When the number of PUSCH layers is not in the subset, it is possible that SRI can be used to select only a restricted subset of combinations of SRS resources from 8 SRS resources. For the restricted subset, for each possible number N of PUSCH layers, it is possible that SRI can only be used to select any combination of SRS resources from the first M SRS resources out of 8 SRS resources, where N≤M≤8. As in the rank threshold-based approach, it is also possible to use a variant design where N≤M<8, in which case M=8 is allowed only when N=8, for example, because it may be that the number of possible combinations of rank values ​​in the second subset is meaningful only when M<8 is true. Alternatively, for this design variant of the rank subset based approach, it may not be necessary to have a special case for N=8, e.g., if rank 8 is generally configured or specified as being in the subset of uplink rank values, then SRI may be used to select any combination of SRS resources for that uplink rank value.

[0138] As yet another possibility, for 8TX non-codebook PUSCH operation, it may be possible to perform network configuration of a customized SRI to SRS resource selection mapping for the UE. The UE may provide an indication of whether the UE supports this mode of operation. Additionally or alternatively, it may be possible for the UE to report the maximum number of entries that may be configured in the network configuration of such a customized SRI to SRS resource selection mapping, for example to limit UE memory requirements to support such an approach. For such a UE, the customized SRI to SRS resource selection mapping may be configured using RRC signaling or MAC CE signaling, as various possibilities.

[0139] For non-coherent codebook PUSCH operation, there may be several TPMI design options for supporting 8TX antenna port operation. As one possibility, it may be the case that all possible port selections are allowed and can be signaled using the TPMI field. For example, similar to the 8-bit SRI field design, it is possible to use an 8-bit bitmap (e.g., for 8TX antenna port uplink operation, the bit width of the TPMI may be fixed to 8), where each bit of the bitmap is associated with a TX antenna port, and if the bit associated with the TX antenna port is set, this may indicate that the corresponding TX antenna port is selected.

[0140] According to at least some embodiments, a rank threshold (R th ) is also possible for non-coherent codebook PUSCH operation. In such a scenario, when the number of PUSCH layers is less than R th When the number of PUSCH layers is equal to or greater than R th When , it is possible that TPMI can be used to select only a restricted subset of combinations of TX antenna ports from the 8 TX antenna ports. For the restricted subset, for each possible number N of PUSCH layers, it is possible that TPMI can be used to select any combination of TX antenna ports from only the first M TX antenna ports out of the 8 TX antenna ports, where N≤M≤8. Note that it is possible to use a variant design where N≤M<8, in the special case that M=8 is allowed only when N=8, for example, because it may be the case that the number of possible combinations is meaningful only when M<8 is true. Figure 8 An example is shown in which R th Possible precoding matrices that can be indicated by the TPMI values ​​used in this rank threshold based TPMI design method in the exemplary scenario where M=2 and M=N.

[0141] At least according to some embodiments, methods in which a subset of uplink rank values ​​may be pre-determined or configured for a wireless device (or more generally for a network or serving cell) are also possible for non-coherent codebook PUSCH operation. In such a scenario, when the number of PUSCH layers is in a subset, it is possible that the TPMI can be used to select any combination of TX antenna ports from 8 TX antenna ports. When the number of PUSCH layers is not in a subset, it is possible that the TPMI can be used to select only a restricted subset of combinations of TX antenna ports from 8 TX antenna ports. For the restricted subset, for each possible number N of PUSCH layers, it is possible that the TPMI can only be used to select any combination of TX antenna ports from the first M TX antenna ports out of the 8 TX antenna ports, where N≤M≤8. As in the rank threshold-based method, it is also possible to use a variant design where N≤M<8, in which case M=8 is allowed only when N=8, for example, because it is possible that the number of possible combinations of rank values ​​in the second subset is meaningful only when M<8 is true. Alternatively, for this design variant of the rank subset based approach, there may not be a need for a special case for N=8, e.g., if rank 8 is generally configured or specified as being in the subset of uplink rank values, then TPMI may be used to select any combination of TX antenna ports for that uplink rank value.

[0142] As another possibility, multiple independent TPMIs may be indicated to support 8TX antenna port non-coherent codebook PUSCH operation. Each TPMI may correspond to a 4TX antenna port TPMI. For a given number N of PUSCH layers indicated by the network, it is possible to split the PUSCH layers as equally as possible between the first TPMI and the second TPMI, for example, so that the first The PUSCH layer can be indicated by the first TPMI on the first 4 SRS ports, and then The first TPMI may be indicated by the second TPMI on the last 4 SRS ports. As another possibility, the network may be able to flexibly split the PUSCH layer between the first TPMI and the second TPMI. In such a scenario, the network may indicate the number of PUSCH layers based on the first TPMI; for each TPMI, it is possible that the number of PUSCH layers may be equal to or less than 4. Fig. 9 Aspects of a possible example scenario in which such a method is used are illustrated. As shown, in the illustrated scenario, a first TPMI may be provided to indicate a codebook selection for the first 4 SRS ports, while a second TPMI may be provided to indicate a codebook selection for the last 4 SRS ports. These selections may be used to fill the diagonal quadrants of the 8TX antenna port precoding matrix, while the remaining non-diagonal quadrants of the 8TX antenna port precoding matrix may be filled with 0s.

[0143] For 8TX partially coherent codebook PUSCH operation, there may be multiple possible partially coherent TX antenna configurations. Figure 10 illustrates several such possible configurations. FIG. 10A to FIG. 10B In , a 4×2 configuration is illustrated, where there may be 4 coherent antenna groups, where each antenna group has 2 coherent antenna elements. According to at least some embodiments, there may be no coherence across different antenna groups. FIG. 10C to FIG. 10D , a 2×4 configuration is illustrated, where there may be 2 coherent antenna groups, where each antenna group has 4 coherent antenna elements. Similar to the 4×2 configuration, at least according to some embodiments, there may be no coherence across different antenna groups.

[0144] For both 4×2 and 2×4 partially coherent codebook 8TX PUSCH operations, it is possible to provide multiple coherent TPMIs, for example where each TPMI corresponds to a 2TX or 4TX antenna port TPMI. Across different antenna groups, it is possible to use a fixed rank (number of layers) splitting approach, for example such that if the number of layers is divisible by the number of coherent antenna groups, each coherent antenna group may contain the same number of PUSCH layers, and in addition one more PUSCH layer may be allocated to the first consecutive coherent antenna group to account for any remaining PUSCH layers. Thus, as an example, in a 4-coherent antenna group configuration with rank=6, the rank splitting may be assigned in a fixed manner as {2,2,1,1}. As another possibility, the rank splitting may be flexible and may be indicated by the network.

[0145] For 8TX partially coherent codebook PUSCH operation, for a 4×2 configuration, a TPMI may be created based on a coherent TPMI with 2 ports. As one possibility, it may be assumed that ports (0,4) form the first coherent antenna group, ports (1,5) form the second coherent antenna group, ports (2,6) form the third coherent antenna group, and ports (3,7) form the fourth coherent antenna group. Fig.11 Various aspects of a possible example scenario in which such an approach is used are illustrated. As shown, in the illustrated scenario, 4 different 2-antenna port TPMIs may be provided and may be used by the UE to populate the 8TX precoding matrix. Two of the 2-antenna port precoding matrices may be used for dual-layer transmission and may be used to allocate two PUSCH layers to each of the first coherent antenna group and the second coherent antenna group. The remaining two 2-antenna port precoding matrices may be used for single-layer transmission and may be used to allocate one PUSCH layer to each of the third coherent antenna group and the fourth coherent antenna group. Note that, as another possibility, other antenna port groupings for 4×2 configurations are also possible, such as (0,2) / (1,3) / (4,6) / (5,7).

[0146] For 8TX partially coherent codebook PUSCH operation, for a 2×4 configuration, a TPMI may be created from a coherent TPMI with 4 ports. As one possibility, it may be assumed that ports (0, 2, 4, 6) form a first coherent antenna group and ports (1, 3, 5, 7) form a second coherent antenna group. Fig.12 Aspects of a possible example scenario in which such an approach is used are illustrated. As shown, in the illustrated scenario, 2 different 4-antenna port TPMIs may be provided and may be used by the UE to populate the 8TX precoding matrix. Each of the 4-antenna port precoding matrices may be used for three-layer transmission and may be used to allocate three PUSCH layers to each of the first coherent antenna group and the second coherent antenna group.

[0147] In the following, further exemplary embodiments are provided.

[0148] A set of embodiments may include an apparatus comprising: a processor configured to cause a wireless device to: establish a wireless link with a cellular base station; perform SRS transmission on each of 8 sounding reference signal (SRS) resources, wherein each SRS resource is associated with a transmit (TX) antenna port; receive an indication of an 8TX antenna port uplink configuration to be used from the cellular base station, wherein the indication of the 8TX antenna port uplink configuration includes an SRS resource indicator (SRI); and perform uplink communication with the cellular base station using the 8TX antenna port uplink configuration.

[0149] According to some embodiments, the SRI comprises an 8-bit bitmap, wherein each bit of the 8-bit bitmap indicates a TX antenna port associated with an SRS resource selected for the 8TX antenna port configuration.

[0150] According to some embodiments, the processor is also configured to cause the wireless device to: determine a maximum number of uplink transmission layers configured to be scheduled by the cellular base station; and determine a bit width of the SRI based at least in part on the maximum number of uplink transmission layers configured to be scheduled by the cellular base station.

[0151] According to some embodiments, the processor is also configured to cause the wireless device to: receive radio resource control (RRC) configuration information indicating the maximum number of uplink transmission layers configured to be scheduled by the cellular base station, wherein the maximum number of uplink transmission layers configured to be scheduled by the cellular base station is determined at least in part based on the RRC configuration information.

[0152] According to some embodiments, the processor is also configured to cause the wireless device to: send wireless device capability information indicating the number of uplink transmission layers supported by the wireless device for non-codebook based uplink operation, wherein the maximum number of uplink transmission layers configured to be scheduled by the cellular base station is determined at least in part based on the wireless device capability information.

[0153] According to some embodiments, the wireless device capability information indicating the number of uplink transmission layers supported by the wireless device for non-codebook based uplink operation is reported on a per component carrier per frequency band per frequency band combination basis.

[0154] According to some embodiments, the bit width of the SRI is determined as: in is the number of possible choices for selecting k candidate values ​​from 8 candidate values, where L max is the maximum number of uplink transmission layers configured to be scheduled by the cellular base station.

[0155] Another set of embodiments may include a method comprising: by a wireless device: establishing a wireless link with a cellular base station; performing SRS transmission on each of 8 sounding reference signal (SRS) resources, wherein each SRS resource is associated with a transmit (TX) antenna port; receiving an indication of an 8TX antenna port uplink configuration to be used from the cellular base station, wherein the indication of the 8TX antenna port uplink configuration includes an SRS resource indicator (SRI); and performing uplink communication with the cellular base station using the 8TX antenna port uplink configuration.

[0156] According to some embodiments, the method also includes: determining a first subset of possible uplink rank values ​​for the wireless link with the cellular base station, wherein for uplink rank values ​​in the first subset of possible uplink rank values, the SRI supports selecting any combination of SRS resources from the 8 SRS resources, and wherein for uplink rank values ​​not in the first subset of possible uplink rank values, the SRI supports selecting a subset of possible combinations of SRS resources from the 8 SRS resources.

[0157] In accordance with some embodiments, for rank values ​​that are not in the first subset of possible uplink rank values, for each possible number N of uplink transmission layers, the SRI supports selecting any combination of the SRS resources from the first M SRS resources of the 8 SRS resources, where N≤M≤8.

[0158] According to some embodiments, the method also includes: receiving SRI to SRS resource selection mapping information for the wireless device from the cellular base station, wherein the SRI indicates using the SRS resource selection associated with the SRI in the SRI to SRS resource selection mapping information as the 8TX antenna port uplink configuration.

[0159] According to some embodiments, the method further includes: sending to the cellular base station an indication of one or more of: whether the wireless device supports configuration of SRI to SRS resource selection mapping information; or the number of SRI to SRS resource selection mapping entries supported by the wireless device.

[0160] Another set of embodiments may include a cellular base station comprising: an antenna; a radio component that is operably coupled to the antenna; and a processor that is operably coupled to the radio component; wherein the cellular base station is configured to: establish a wireless link with a wireless device; receive an SRS transmission from the wireless device on each of 8 sounding reference signal (SRS) resources, wherein each SRS resource is associated with a transmit (TX) antenna port; provide an indication of an 8TX antenna port uplink configuration to the wireless device, wherein the indication of the 8TX antenna port uplink configuration includes an SRS resource indicator (SRI) configured to indicate a non-codebook uplink configuration; and receive uplink communications from the wireless device, wherein the uplink communications are sent using the 8TX antenna port uplink configuration.

[0161] According to some embodiments, the SRI comprises an 8-bit bitmap, wherein each bit of the 8-bit bitmap indicates a TX antenna port associated with an SRS resource selected for the 8TX antenna port configuration.

[0162] According to some embodiments, the cellular base station is also configured to: determine a maximum number of uplink transmission layers to be scheduled for the wireless device; and determine a bit width of the SRI based at least in part on the maximum number of uplink transmission layers to be scheduled for the wireless device.

[0163] According to some embodiments, the cellular base station is further configured to provide to the wireless device an indication of the maximum number of uplink transmission layers to be scheduled for the wireless device.

[0164] According to some embodiments, the cellular base station is also configured to: receive wireless device capability information, the wireless device capability information indicating the number of uplink transmission layers supported by the wireless device for non-codebook based uplink operation, wherein the maximum number of uplink transmission layers to be scheduled for the wireless device is determined at least in part based on the wireless device capability information.

[0165] According to some embodiments, the cellular base station is also configured to: determine an uplink rank threshold for a wireless link with the cellular base station, wherein for rank values ​​below the uplink rank threshold, the SRI supports selecting any combination of SRS resources from the 8 SRS resources, wherein for rank values ​​equal to or greater than the uplink rank threshold, the SRI supports selecting a subset of possible combinations of SRS resources from the 8 SRS resources.

[0166] According to some embodiments, the cellular base station is also configured to: send SRI to SRS resource selection mapping information to the wireless device; and select the SRI for the wireless device based at least in part on the SRI to SRS resource selection mapping information, wherein the SRI indicates use of the SRS resource selection associated with the SRI in the SRI to SRS resource selection mapping information as the 8TX antenna port uplink configuration.

[0167] According to some embodiments, the cellular base station is also configured to: receive from the wireless device an indication of one or more of: whether the wireless device supports configuration of SRI to SRS resource selection mapping information; or the number of SRI to SRS resource selection mapping entries supported by the wireless device.

[0168] Another set of embodiments may include an apparatus comprising: a processor configured to cause a wireless device to: establish a wireless link with a cellular base station; receive an indication of an 8-transmit (TX) antenna port uplink configuration to be used from the cellular base station, wherein the indication of the 8TX antenna port uplink configuration includes one or more transmit precoding matrix indicators (TPMIs) configured to indicate a codebook uplink configuration; and perform uplink communication with the cellular base station using the 8TX antenna port uplink configuration.

[0169] According to some embodiments, the indication of the 8TX antenna port uplink configuration includes one or more TPMIs configured to indicate a non-coherent codebook uplink configuration.

[0170] According to some embodiments, the TPMI comprises an 8-bit bitmap, wherein each bit of the 8-bit bitmap indicates a selected TX antenna port for the 8TX antenna port configuration.

[0171] According to some embodiments, the processor is also configured to cause the wireless device to: determine a subset of uplink rank values ​​for the wireless link with the cellular base station, wherein for uplink rank values ​​in the subset of uplink rank values, the TPMI supports selecting any combination of TX antenna ports from 8 TX antenna ports, wherein for uplink rank values ​​not in the subset of uplink rank values, the TPMI supports selecting a subset of possible combinations of TX antenna ports from the 8 TX antenna ports.

[0172] According to some embodiments, for rank values ​​that are not in the subset of uplink rank values ​​used for the wireless link with the cellular base station, for each possible number N of uplink transmit layers, the TPMI supports selecting any combination of the TX antenna ports from the first M TX antenna ports of the 8 TX antenna ports, where N≤M≤8.

[0173] According to some embodiments, the indication of the 8TX antenna port uplink configuration includes two 4TX antenna port TPMIs.

[0174] Another set of embodiments may include a method comprising: by a wireless device: establishing a wireless link with a cellular base station; receiving an indication of an 8-transmit (TX) antenna port uplink configuration to be used from the cellular base station, wherein the indication of the 8TX antenna port uplink configuration includes one or more transmit precoding matrix indicators (TPMIs) configured to indicate a codebook uplink configuration; and performing uplink communication with the cellular base station using the 8TX antenna port uplink configuration.

[0175] According to some embodiments, the indication of the 8TX antenna port uplink configuration includes a plurality of TPMIs configured to indicate a partially coherent codebook uplink configuration.

[0176] According to some embodiments, the plurality of TPMIs includes a TPMI for each antenna group in a plurality of coherent antenna groups of the wireless device.

[0177] According to some embodiments, the plurality of TPMIs include TPMIs configured with different numbers of uplink transmission layers.

[0178] According to some embodiments, the 8TX antenna port configuration includes 4 coherent antenna groups, each of which includes 2 antenna elements, and the indication of the 8TX antenna port uplink configuration includes a 2TX antenna port TPMI for each of the 4 coherent antenna groups.

[0179] According to some embodiments, the 8TX antenna port configuration includes 2 coherent antenna groups, each of which includes 4 antenna elements, and the indication of the 8TX antenna port uplink configuration includes a 4TX antenna port TPMI for each of the 2 coherent antenna groups.

[0180] Yet another set of embodiments may include a cellular base station comprising: an antenna; a radio component operably coupled to the antenna; and a processor operably coupled to the radio component; wherein the cellular base station is configured to: establish a wireless link with a wireless device; provide an indication of an 8-transmit (TX) antenna port uplink configuration to be used to the wireless device, wherein the indication of the 8TX antenna port uplink configuration includes one or more transmit precoding matrix indicators (TPMIs) configured to indicate a codebook uplink configuration; and receive uplink communications from the wireless device, wherein the uplink communications are sent using the 8TX antenna port uplink configuration.

[0181] According to some embodiments, the indication of the 8TX antenna port uplink configuration includes one or more TPMIs configured to indicate a non-coherent codebook uplink configuration.

[0182] According to some embodiments, the TPMI comprises an 8-bit bitmap, wherein each bit of the 8-bit bitmap indicates a selected TX antenna port for the 8TX antenna port configuration.

[0183] According to some embodiments, the cellular base station is also configured to: determine a subset of possible uplink rank values ​​for the wireless device, wherein for uplink rank values ​​in the determined subset of possible uplink rank values ​​for the wireless device, the TPMI supports selecting any combination of TX antenna ports from 8 TX antenna ports, wherein for uplink rank values ​​that are not in the determined subset of possible uplink rank values ​​for the wireless device, the TPMI supports selecting a subset of possible combinations of TX antenna ports from the 8 TX antenna ports.

[0184] According to some embodiments, the indication of the 8TX antenna port uplink configuration includes a plurality of TPMIs configured to indicate a partially coherent codebook uplink configuration.

[0185] According to some embodiments, the plurality of TPMIs includes a TPMI for each antenna group in a plurality of coherent antenna groups of the wireless device.

[0186] According to some embodiments, the one or more TPMIs include a plurality of TPMIs configured with different numbers of uplink transmission layers.

[0187] According to some embodiments, the cellular base station is further configured to provide an indication of an uplink transmit layer split between the plurality of TPMIs.

[0188] Yet another example embodiment may include a method comprising: performing, by a wireless device, any or all of the foregoing examples.

[0189] Another example embodiment may include a device comprising: an antenna; a radio coupled to the antenna; and a processor operably coupled to the radio, wherein the device is configured to implement any or all of the foregoing examples.

[0190] Another set of exemplary embodiments may include a non-transitory computer-accessible storage medium including program instructions that, when executed at a device, cause the device to implement any or all portions of any of the foregoing examples.

[0191] Yet another set of exemplary embodiments may include a computer program comprising instructions for performing any or all portions of any of the foregoing examples.

[0192] Yet another set of exemplary embodiments may include an apparatus comprising means for performing any or all elements of any of the preceding examples.

[0193] Another exemplary set of embodiments may include an apparatus comprising a processor configured to cause a wireless device to perform any or all elements of any of the foregoing examples.

[0194] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

[0195] By interpreting each message / signal X received by a user equipment (UE) in the downlink as a message / signal X sent by the base station, and interpreting each message / signal Y sent by the UE in the uplink as a message / signal Y received by the base station, any of the methods for operating a UE described herein may become the basis for the corresponding method for operating a base station.

[0196] The embodiments of the present disclosure may be implemented in any of a variety of forms. For example, in some embodiments, the subject matter may be implemented as a computer-implemented method, a computer-readable storage medium, or a computer system. In other embodiments, one or more custom-designed hardware devices such as ASICs may be used to implement the subject matter. In other embodiments, one or more programmable hardware elements such as FPGAs may be used to implement the subject matter.

[0197] In some embodiments, a non-transitory computer-readable storage medium (e.g., a non-transitory storage element) may be configured to store program instructions and / or data, wherein if the program instructions are executed by a computer system, the computer system is caused to perform a method, such as any method implementation of the method embodiments described herein, or any combination of the method implementations described herein, or any subset of any method implementation of the method embodiments described herein, or any combination of such subsets.

[0198] In some embodiments, a device (e.g., a UE) may be configured to include a processor (or a group of processors) and a memory medium (or a memory element), wherein the memory medium stores program instructions, wherein the processor is configured to read and execute these program instructions from the memory medium, wherein these program instructions are executable to implement any method implementation in the various method implementations described herein (or any combination of the method implementations described herein, or any subset of any method implementation in the method implementations described herein, or any combination of such subsets). The device may be implemented in any of various forms.

[0199] Although the above embodiments have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to include all such variations and modifications.

Claims

1. A device, comprising: A processor configured to cause the wireless device to: performing a sounding reference signal (SRS) transmission on each of eight SRS resources, wherein each SRS resource is associated with a transmit (TX) antenna port; receiving an indication of an 8TX antenna port uplink configuration from a cellular base station, wherein the indication of the 8TX antenna port uplink configuration comprises an SRS resource indicator (SRI); and Uplink communications with the cellular base station are performed using the 8TX antenna port uplink configuration.

2. The device according to claim 1, The SRI comprises an 8-bit bitmap, wherein each bit of the 8-bit bitmap indicates whether a TX antenna port associated with an SRS resource is selected for the 8TX antenna port configuration.

3. The apparatus of claim 1 , wherein the processor is further configured to cause the wireless device to: determining a maximum number of uplink transmission layers configured to be scheduled by the cellular base station; and The bit width of the SRI is determined based at least in part on the maximum number of uplink transmission layers configured to be scheduled by the cellular base station.

4. The apparatus of claim 3, wherein the processor is further configured to cause the wireless device to: receiving radio resource control (RRC) configuration information indicating the maximum number of uplink transmission layers configured to be scheduled by the cellular base station, The maximum number of uplink transmission layers configured to be scheduled by the cellular base station is determined based at least in part on the RRC configuration information.

5. The apparatus of claim 3, wherein the processor is further configured to cause the wireless device to: transmitting wireless device capability information indicating a number of uplink transmit layers supported by the wireless device for non-codebook based uplink operation, Wherein the maximum number of uplink transmission layers configured to be scheduled by the cellular base station is determined based at least in part on the wireless device capability information.

6. The apparatus of claim 5, wherein the wireless device capability information indicating the number of uplink transmission layers supported by the wireless device for non-codebook based uplink operation is reported on a per component carrier per frequency band per frequency band combination basis.

7. The apparatus of claim 3, wherein the bit width of the SRI is determined as: in is the number of possible choices for selecting k candidate values ​​from 8, Where L max is the maximum number of uplink transmission layers configured to be scheduled by the cellular base station.

8. A method comprising: performing a sounding reference signal (SRS) transmission on each of eight SRS resources, wherein each SRS resource is associated with a transmit (TX) antenna port; receiving an indication of an 8TX antenna port uplink configuration from a cellular base station, wherein the indication of the 8TX antenna port uplink configuration comprises an SRS resource indicator (SRI); and Uplink communications with the cellular base station are performed using the 8TX antenna port uplink configuration.

9. The method according to claim 8, wherein the method further comprises: determining a first subset of possible uplink rank values ​​for a wireless link with the cellular base station, wherein for an uplink rank value in the first subset of possible uplink rank values, the SRI supports any combination of selecting SRS resources from the 8 SRS resources, Wherein for uplink rank values ​​that are not in the first subset of possible uplink rank values, the SRI supports selecting a subset of possible combinations of SRS resources from the 8 SRS resources.

10. The method according to claim 9, Wherein for rank values ​​not in the first subset of possible uplink rank values, for each possible number N of uplink transmission layers, the SRI supports selecting any combination of the SRS resources from the first M SRS resources of the 8 SRS resources, where N≤M≤8.

11. The method according to claim 8, wherein the method further comprises: receiving SRI to SRS resource selection mapping information for the wireless device from the cellular base station, The SRI indicates using the SRS resource selection associated with the SRI in the SRI to SRS resource selection mapping information as the 8TX antenna port uplink configuration.

12. The method according to claim 11, wherein the method further comprises: Sending to the cellular base station an indication of one or more of the following: Whether the wireless device supports configuration of SRI to SRS resource selection mapping information; or The number of SRI to SRS resource selection mapping entries supported by the wireless device.

13. A cellular base station, the cellular base station comprising: antenna; a radio operably coupled to the antenna; and a processor operatively coupled to the radio; The cellular base station is configured as follows: receiving a sounding reference signal (SRS) transmission from a wireless device on each of eight SRS resources, wherein each SRS resource is associated with a transmit (TX) antenna port; providing an indication of an 8TX antenna port uplink configuration to the wireless device, wherein the indication of the 8TX antenna port uplink configuration comprises an SRS resource indicator (SRI) configured to indicate a non-codebook uplink configuration; and An uplink communication is received from the wireless device, wherein the uplink communication is sent using the 8TX antenna port uplink configuration.

14. The cellular base station according to claim 13, The SRI comprises an 8-bit bitmap, wherein each bit of the 8-bit bitmap indicates whether a TX antenna port associated with an SRS resource is selected for the 8TX antenna port configuration.

15. The cellular base station according to claim 13, wherein the cellular base station is further configured to: determining a maximum number of uplink transmission layers to be scheduled for the wireless device; and A bit width of the SRI is determined based at least in part on the maximum number of uplink transmission layers to be scheduled for the wireless device.

16. The cellular base station according to claim 15, wherein the cellular base station is further configured to: An indication of the maximum number of uplink transmission layers to be scheduled for the wireless device is provided to the wireless device.

17. The cellular base station according to claim 15, wherein the cellular base station is further configured to: receiving wireless device capability information indicating a number of uplink transmit layers supported by the wireless device for non-codebook based uplink operation, Wherein the maximum number of uplink transmission layers to be scheduled for the wireless device is determined based at least in part on the wireless device capability information.

18. The cellular base station according to claim 13, wherein the cellular base station is further configured to: determining an uplink rank threshold for a wireless link with the cellular base station, wherein for a rank value lower than the uplink rank threshold, the SRI supports selecting any combination of SRS resources from the 8 SRS resources, Wherein for rank values ​​equal to or greater than the uplink rank threshold, the SRI supports selecting a subset of possible combinations of SRS resources from the 8 SRS resources.

19. The cellular base station according to claim 13, wherein the cellular base station is further configured to: sending SRI to SRS resource selection mapping information to the wireless device; and The SRI for the wireless device is selected based at least in part on the SRI to SRS resource selection mapping information, wherein the SRI indicates use of the SRS resource selection associated with the SRI in the SRI to SRS resource selection mapping information as the 8TX antenna port uplink configuration.

20. The cellular base station according to claim 19, wherein the cellular base station is further configured to: Receiving from the wireless device an indication of one or more of: Whether the wireless device supports configuration of SRI to SRS resource selection mapping information; or The number of SRI to SRS resource selection mapping entries supported by the wireless device.

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