Flexible Aperiodic SRS Triggering in Cellular Communication Systems

Abstract

The present invention provides a cellular base station (BS) and a UE, where the BS transmits more flexible downlink control information (DCI) to the UE, and the UE is capable of receiving and processing the received DCI message. The DCI message can have a DCI format of 0_1 or 0_2, and can also include a UL-SCH set to 0, a CSI request field all of 0, and an SRS request field with a non-zero value. The DCI message can indicate to the UE that the UE should: 1) transmit an aperiodic SRS corresponding to the SRS request; and 2) the UE should not transmit on the PUSCH. The DCI can include an existing field specifying a time slot offset or beam information that can be used when transmitting the aperiodic SRS. For higher efficiency, the base station can also generate a DCI message with an SRS trigger, which targets multiple UEs or multiple UE groups in a group.

Description

Technical Field

[0001] The present invention relates to wireless communication and, more particularly, to apparatuses, systems, and methods for more flexibly providing trigger signaling to trigger UE transmissions of aperiodic sounding reference signals.

[0002] Description of Related Art

[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 telephone calls, many mobile devices now also provide access to the Internet, email, text messaging, and navigation using the Global Positioning System (GPS), and are capable of operating sophisticated applications that utilize these features.

[0004] Long Term Evolution (LTE) is the preferred technology for most wireless network operators globally, thereby providing mobile broadband data and high-speed Internet access to their user bases. LTE was first proposed in 2004 and first standardized in 2008. Since then, as the use of wireless communication systems has grown exponentially, the demand on wireless network operators has increased to support higher capacities for a higher density of mobile broadband users. Accordingly, research on new radio access technologies began in 2015, and in 2017, the first version of the fifth-generation New Radio (5G NR) was standardized.

[0005] 5G-NR (also simply referred to as NR), compared to LTE, provides higher capacity for a higher density of mobile broadband users, while also supporting device-to-device ultra-reliable and massive machine-type communication, as well as lower latency and / or lower battery consumption. In addition, compared to current LTE, NR allows for more flexible UE scheduling. Accordingly, efforts are being made to leverage the potentially higher throughput at higher frequencies in the continued development of 5G NR.

[0006] One aspect of current cellular communication operations is for a UE to provide a sounding reference signal (SRS) to a base station so that the base station can evaluate the quality of the uplink channel. Improvements in this area are desired. Summary of the Invention

[0007] Embodiments relate to wireless communication and, more particularly, to apparatuses, systems, and methods for more flexibly triggering aperiodic SRS transmissions by a UE.

[0008] Some embodiments relate to a cellular base station (BS) that includes a plurality of antennas, radio components operably coupled to the plurality of antennas, and a processor operably coupled to the radio components. The cellular base station can be configured to determine that a UE should transmit an aperiodic sounding reference signal (SRS) to the base station. In response to that determination, the base station can transmit downlink control information (DCI) to the UE. The downlink control information (DCI) can also indicate to the UE that the UE should transmit an aperiodic SRS to the base station. The DCI can also include one or more parameter fields that are set to indicate that no uplink shared channel data is requested from the UE. Thus, the DCI message can specify that the UE will transmit an SRS message on the uplink shared channel without any accompanying data from the UE.

[0009] The DCI message can have a DCI format of 0_1 or 0_2. Additionally, the DCI message can include an uplink shared channel indicator that is set to 0, a channel state information (CSI) request field that is all 0s, and an SRS request field that has a non-zero value. The DCI message can indicate to the UE that the UE should: 1) transmit an aperiodic SRS corresponding to the non-zero value in the SRS request field to the base station; and 2) the UE should not transmit on the physical uplink shared channel.

[0010] The DCI can include a time domain resource allocation field having a value that specifies a time slot offset for the aperiodic SRS. The DCI can also include an SRS resource indicator field that specifies beam information that can be used by the UE when transmitting the aperiodic SRS to the base station.

[0011] In the case where the DCI includes a channel state information (CSI) request field with a value of 0, an uplink shared channel indicator (UL-SCH) field with a value of 0, and an SRS request field with a value of 0, the DCI message can be interpreted by the UE as an invalid DCI.

[0012] The base station can also be configured to generate a DCI message with an SRS trigger that targets multiple UEs in a group, or even further targets multiple groups of UEs, where each group includes multiple UEs. This allows the base station to more efficiently provide an SRS trigger to each of the multiple UEs with reduced transmission overhead.

[0013] The embodiments described herein also relate to a user equipment (UE) that is capable of receiving and processing the received DCI message as described above and is capable of transmitting an SRS in response thereto.

[0014] The present invention content aims 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 topic described herein in any way. Other features, aspects, and advantages of the topic described herein will become apparent from the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] A better understanding of the subject matter can be obtained when considering the following detailed description of various embodiments in conjunction with the following drawings, in which:

[0016] Figure 1A An exemplary wireless communication system is shown in accordance with some embodiments.

[0017] Figure 1B An example of a base station (BS) and an access point communicating with a user equipment (UE) device is shown in accordance with some embodiments.

[0018] Figure 2 An exemplary block diagram of a BS is shown in accordance with some embodiments.

[0019] Figure 3 An exemplary block diagram of a UE is shown in accordance with some embodiments.

[0020] Figure 4 An exemplary block diagram of a cellular communication circuit is shown in accordance with some embodiments.

[0021] Figure 5 An example of a baseband processor architecture for a UE is shown in accordance with some embodiments;

[0022] Figure 6A and Figure 6B is a flowchart showing the transmission of an SRS trigger to a UE in accordance with some embodiments;

[0023] Figure 7A and Figure 7B is a flowchart showing a method for transmitting DCI information operable to trigger multiple UEs in accordance with some embodiments; and

[0024] Figure 8 shows a format of downlink control information (DCI) operable to trigger multiple UEs in two or more groups in accordance with some embodiments.

[0025] Although the features described herein may be susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and are described in detail herein. However, it should be understood that the drawings and the detailed description thereof are not intended to limit the present disclosure to the particular forms disclosed, but on the contrary, the intention is 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

[0026] Acronyms

[0027] Various acronyms are used throughout this disclosure. The definitions of the most prominent acronyms that may appear throughout this disclosure are as follows:

[0028] ··3GPP: 3rd Generation Partnership Project

[0029] ··UE: User Equipment

[0030] ·RF: Radio Frequency

[0031] ·BS: Base Station

[0032] ·DL: Downlink

[0033] ·UL: Uplink

[0034] ·LTE: Long Term Evolution

[0035] ·NR: New Radio

[0036] ·5GS: 5G System

[0037] ·5GMM: 5GS Mobility Management

[0038] ·5GC / 5GCN: 5G Core Network

[0039] ·SRS: Sounding Reference Signal

[0040] ·AP-SRS: Aperiodic Sounding Reference Signal

[0041] ·IE: Information Element

[0042] ·CE: Control Element

[0043] ·MAC: Medium Access Control

[0044] ·SSB: Synchronization Signal Block

[0045] ·CSI-RS: Channel State Information Reference Signal

[0046] ·PDCCH: Physical Downlink Control Channel

[0047] · PDSCH: Physical Downlink Shared Channel

[0048] · RRC: Radio Resource Control

[0049] · RRM: Radio Resource Management

[0050] · TCI: Transmission Configuration Indicator

[0051] · DCI: Downlink Control Information

[0052] · RNTI: Radio Network Temporary Identifier

[0053] Terminology

[0054] The following is a glossary of terms used in this disclosure:

[0055] 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-ROMs, floppy disks, or magnetic 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 that executes a program, or may be located in a different second computer system that is connected to the first computer system via a network such as the Internet. In the latter case, the second computer system may provide program instructions to the first computer for execution. The term "memory medium" may include two or more memory media that 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) executable by one or more processors.

[0056] Carrier medium - The memory medium as described above, as well as physical transmission media such as buses, networks, and / or other physical transmission media that convey signals such as electrical, electromagnetic, or digital signals.

[0057] Programmable hardware element - Includes various hardware devices that include a plurality of programmable function blocks connected via programmable interconnects. Examples include FPGA (Field Programmable Gate Array), PLD (Programmable Logic Device), FPOA (Field Programmable Object Array), and CPLD (Complex PLD). The programmable function blocks can vary from fine-grained (combinational logic components or look-up tables) to coarse-grained (arithmetic logic units or processor cores). Programmable hardware elements may also be referred to as "configurable logic components".

[0058] Computer system (or computer) - Any one of various types of computing or processing systems, including personal computer systems (PCs), mainframe computer systems, workstations, network appliances, Internet appliances, personal digital assistants (PDAs), television systems, grid computing systems, or other devices or combinations of devices. Generally speaking, the term "computer system" can be broadly defined to cover any device (or combination of devices) having at least one processor that executes instructions from a memory medium.

[0059] User equipment (UE) (or "UE device") - Any one of various types of computer system devices that are mobile or portable and perform wireless communication. Examples of UE devices include mobile phones or smartphones (e.g., iPhone TM , Android TM -based phones), portable gaming devices (e.g., Nintendo DS TM , PlayStation Portable TM , Gameboy Advance TM , iPhone TM ), laptop computers, wearable devices (e.g., smartwatches, smart glasses), PDAs, portable Internet devices, music players, data storage devices, other handheld devices, unmanned aerial vehicles (UAVs) (e.g., drones), UAV controllers (UACs), etc. Generally speaking, the term "UE" or "UE device" can be broadly defined to cover any electronic, computing, and / or telecommunications device (or combination of devices) that is easily transportable by a user and capable of wireless communication.

[0060] Base station - The term "base station" has the full scope of its ordinary meaning and includes at least a wireless communication station that is installed at a fixed location and used for communication as part of a wireless telephone system or radio system.

[0061] Processing element (or processor) - Refers to various elements or combinations of elements that can perform functions in a device such as a user equipment or a cellular network device. Processing elements can include, for example: a processor 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 combination of the above.

[0062] Channel - A medium for conveying information from a transmitter to a receiver. It should be noted that since the characteristics of the term "channel" can vary according to different wireless protocols, the term "channel" as used in the present invention can be considered to be used in a manner that conforms to the standards of the type of device to which the term usage refers. In some standards, the channel width can be variable (e.g., depending on device capabilities, frequency band conditions, etc.). For example, LTE can support scalable channel bandwidths from 1.4 MHz to 20 MHz. In contrast, a WLAN channel can be 22 MHz wide, while a Bluetooth channel can be 1 MHz wide. Other protocols and standards can include different definitions of channels. Additionally, some standards can define and use multiple types of channels, such as different channels for uplink or downlink and / or different channels for different purposes such as data, control information, etc.

[0063] Frequency Band - The term "frequency band" has its full range of ordinary meanings and at least includes a segment of the spectrum (e.g., radio frequency spectrum) in which channels are used or set aside for the same purpose.

[0064] Wi-Fi - The term "Wi-Fi" (or WiFi) has its full range of ordinary meanings and at least includes 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 different from cellular networks.

[0065] 3GPP Access - Refers to access (e.g., radio access technology) specified by 3GPP standards. These accesses include, but are not limited to, GSM / GPRS, LTE, LTE-A, and / or 5G NR. Generally speaking, 3GPP access refers to various types of cellular access technologies.

[0066] Non-3GPP Access - Refers to any access (e.g., radio access technology) not specified by 3GPP standards. These accesses include, but are not limited to, WiMAX, CDMA2000, Wi-Fi, WLAN, and / or fixed networks. Non-3GPP access can be divided into two categories, "trusted" and "untrusted": Trusted non-3GPP access can directly interact with the evolved packet core (EPC) and / or 5G core (5GC), while untrusted non-3GPP communicates with the EPC / 5GC via network entities such as the evolved packet data gateway and / or 5G NR gateway. Generally speaking, non-3GPP access refers to various types of non-cellular access technologies.

[0067] Automatically - means that an action or operation is 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 through user input. Thus, the term "automatically" is contrary to an operation being performed or specified manually by a user, where the user provides input to directly perform the operation. An automatic process can be initiated by input provided by the user, but the subsequent actions that are "automatically" performed are not specified by the user, i.e., they are not performed "manually", where the user specifies each action to be performed. For example, a user fills out a spreadsheet manually by selecting each field and providing input to specify information (e.g., by typing information, selecting checkboxes, radio selections, etc.), even though the computer system must update the spreadsheet in response to the user's actions. The spreadsheet can be filled out automatically by the computer system, where the computer system (e.g., software executed on the computer system) analyzes the fields of the spreadsheet and fills out the spreadsheet without any user input specifying the answers to the fields. As indicated above, the user can invoke the automatic filling of the spreadsheet but does not participate in the actual filling of the spreadsheet (e.g., the user does not manually specify the answers to the fields but they are completed automatically). This specification provides various examples of operations that are automatically performed in response to actions taken by the user.

[0068] About - means close to the correct or exact value. For example, about can mean a value within 1% to 10% of the exact (or desired) value. However, it should be noted that the actual threshold (or tolerance) can depend on the application. For example, in some embodiments, "about" can mean within 0.1% of some specified or desired value, while in various other embodiments, depending on the expectations or requirements of the particular application, the threshold can be, for example, 2%, 3%, 5%, etc.

[0069] Concurrent - means parallel execution or implementation, where tasks, processes, or programs are executed in at least a partially overlapping manner. For example, concurrency can be achieved using "strong" or strict parallelism, where tasks are executed (at least partially) in parallel on corresponding computing elements; or using "weak parallelism", where tasks are executed in an interleaved manner (e.g., through time multiplexing of execution threads).

[0070] Various components may be described as “configured to” perform one or more tasks. In such an environment, “configured to” is a broad statement that generally means “having” the “structure” to perform one or more tasks during operation. Thus, even when a component is not currently performing a task, the component can be configured to perform the task (e.g., a set of electrical conductors can be configured to electrically connect a module to another module even when the two modules are not connected). In some contexts, “configured to” can be a broad statement that generally means “having” the “circuitry” to perform one or more tasks during operation. Thus, even when a component is not currently powered on, the component can be configured to perform a task. Generally, the circuitry that forms the structure corresponding to “configured to” may include hardware circuitry.

[0071] For ease of description, various components may be described as performing one or more tasks. Such a description should be interpreted to include the phrase “configured to”. A component described as configured to perform one or more tasks is expressly intended not to invoke an interpretation under 35 U.S.C. § 112(f) for that component.

[0072] Figure 1A and 1B : communication system

[0073] Figure 1A illustrates a simplified exemplary wireless communication system according to some embodiments. Note that Figure 1A the system is merely an example of a possible system, and features of the present disclosure may be implemented in any one of various systems as needed.

[0074] As shown, the exemplary wireless communication system includes a base station 102A that communicates with one or more user devices 106A, user devices 106B through user device 106N, etc. via a transmission medium. Each user device may be referred to herein as a “user equipment” (UE). Thus, user device 106 is referred to as a UE or a UE device.

[0075] The base station (BS) 102A may be a transceiver base station (BTS) or a cell site (“cellular base station”), and may include hardware that enables wireless communication with UEs 106A through 106N.

[0076] The communication area (or coverage area) of a base station can be referred to as a "cell". Base station 102A and UE 106 can be configured to communicate via a transmission medium using any one of various radio access technologies (RATs), which are also referred to as wireless communication technologies or telecommunication standards, such as GSM, UMTS (associated with, for example, WCDMA or TD-SCDMA air interfaces), LTE, Advanced LTE (LTE-A), 5G New Radio (5G NR), HSPA, 3GPP2 CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), and so on. Note that if base station 102A is implemented in the context of LTE, it may alternatively be referred to as an "eNodeB" or "eNB". Note that if base station 102A is implemented in the context of 5G NR, it may alternatively be referred to as a "gNodeB" or "gNB".

[0077] As shown, base station 102A can also be equipped to communicate with network 100 (e.g., among various possibilities, the core network of a cellular service provider, a telecommunication network such as the Public Switched Telephone Network (PSTN) and / or the Internet). Thus, base station 102A can facilitate communication between user devices and / or between user devices and network 100. In particular, cellular base station 102A can provide UE 106 with various communication capabilities such as voice, SMS, and / or data services.

[0078] Base station 102A and other similar base stations operating according to the same or different cellular communication standards (such as base stations 102B... 102N) can thus be provided as a network of cells that can provide continuous or nearly continuous overlapping services to UEs 106A-N and similar devices over a geographical area via one or more cellular communication standards.

[0079] Thus, although base station 102A can act as the "serving cell" of UEs 106A-N as shown in Figure 1A , each UE 106 may also be able to receive signals (and potentially be within its communication range) from one or more other cells (which can be provided by base stations 102B-N and / or any other base stations), and these one or more other cells can be referred to as "adjacent cells". Such cells may also be able to facilitate communication between user devices and / or between user devices and network 100. Such cells can include "macro" cells, "micro" cells, "pico" cells, and / or any various other granularities of cells providing service area sizes. For example, base stations 102A to 102B shown in Figure 1A can be macro cells, while base station 102N can be a micro cell. Other configurations are also possible.

[0080] In some embodiments, base station 102A may be a next-generation base station, e.g., a 5G New Radio (5G NR) base station or a "gNB". In some embodiments, the gNB may be connected to a traditional Evolved Packet Core (EPC) network and / or connected to a NR Core (NRC) network. Additionally, a gNB cell may include one or more Transmission and Reception Points (TRPs). Further, a UE capable of operating according to 5G NR may be connected to one or more TRPs within one or more gNBs.

[0081] Note that UE 106 is capable of communicating using multiple wireless communication standards. For example, in addition to at least one cellular communication protocol (e.g., GSM, UMTS (associated with, e.g., WCDMA or TD-SCDMA air interfaces), LTE, LTE-A, 5G NR, HSPA, 3GPP2 CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), etc.), UE 106 may be configured to communicate using wireless networking (e.g., Wi-Fi) and / or peer-to-peer wireless communication protocols (e.g., Bluetooth, Wi-Fi peer-to-peer, etc.). If desired, UE 106 may also or alternatively be configured to communicate using one or more Global Navigation Satellite Systems (GNSS, e.g., GPS or GLONASS), one or more mobile television broadcast standards (e.g., ATSC-M / H or DVB-H), and / or any other wireless communication protocol. Other combinations of wireless communication standards (including more than two wireless communication standards) are also possible.

[0082] Figure 1B Shown is a user equipment 106 (e.g., one of devices 106A to 106N) communicating with base station 102 and access point 112 according to some embodiments. UE 106 may be a device having cellular communication capabilities and non-cellular communication capabilities (e.g., Bluetooth, Wi-Fi, etc.), such as a mobile phone, a handheld device, a computer or a tablet computer, or almost any type of wireless device.

[0083] UE 106 may include a processor configured to execute program instructions stored in a memory. UE 106 may perform any of the method embodiments described herein by executing such stored instructions. Alternatively or in addition, UE 106 may include programmable hardware elements, such as a Field Programmable Gate Array (FPGA) configured to perform any of the method embodiments described herein or any part of any of the method embodiments described herein.

[0084] UE 106 may include one or more antennas for communicating using one or more wireless communication protocols or technologies. In some embodiments, UE 106 may be configured to communicate using, for example, CDMA2000 (1xRTT / 1xEV-DO / HRPD / eHRPD), LTE / Advanced LTE, or 5G NR and / or GSM, LTE, Advanced LTE, or 5G Nr using a single shared radio component. The shared radio may be coupled to a single antenna or may be coupled to multiple antennas (e.g., for MIMO) for performing wireless communication. Generally, the radio component may include any combination of a baseband processor, analog radio frequency (RF) signal processing circuitry (e.g., including filters, mixers, oscillators, amplifiers, etc.) or digital processing circuitry (e.g., for digital modulation and other digital processing). Similarly, the radio component may implement one or more receive chains and transmit chains using the foregoing hardware. For example, UE 106 may share one or more portions of a receive chain and / or a transmit chain among multiple wireless communication technologies such as those discussed above.

[0085] In some embodiments, UE 106 may include separate transmit chains and / or receive chains (e.g., including separate antennas and other radio components) for each wireless communication protocol it is configured to communicate with. As another possibility, UE 106 may include one or more radio components shared among multiple wireless communication protocols and one or more radio components uniquely used by a single wireless communication protocol. For example, UE 106 may include a shared radio component for communicating using either LTE or 5GNR (or LTE or 1xRTT, or LTE or GSM) and separate radio components for communicating using each of Wi-Fi and Bluetooth. Other configurations are possible.

[0086] Figure 2 : Base Station Block Diagram

[0087] Figure 2 An exemplary block diagram of base station 102 is shown in accordance with some embodiments. Note that Figure 3 the base station shown is merely one example of possible base stations. As shown, base station 102 may include a processor 204 that may execute program instructions for base station 102. Processor 204 may also be coupled to a memory management unit (MMU) 240 or other circuits or devices that may be configured to receive addresses from processor 204 and translate those addresses to locations in a memory (e.g., memory 260 and read-only memory (ROM) 250).

[0088] Base station 102 may include at least one network port 270. The network port 270 may be configured to couple to a telephone network and provide access to the telephone network for a plurality of devices, such as UE device 106, as described above in Figure 1A , Figure 1B and Figure 2 .

[0089] The network port 270 (or an additional network port) may also be configured or alternatively configured to couple to a cellular network, such as the 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 UE device 106. In some cases, the network port 270 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).

[0090] In some embodiments, base station 102 may be a next-generation base station, e.g., a 5G New Radio (5G NR) base station, or a "gNB". In such embodiments, base station 102 may be connected to a legacy Evolved Packet Core (EPC) network and / or connected to a NR Core (NRC) network. Additionally, base station 102 may be considered a 5G NR cell and may include one or more Transmission and Reception Points (TRPs). Additionally, a UE capable of operating according to 5G NR may be connected to one or more TRPs within one or more gNBs.

[0091] Base station 102 may include at least one antenna 234 and possibly a plurality of antennas. The at least one antenna 234 may be configured to operate as a wireless transceiver and may be further configured to communicate with UE device 106 via radio component 230. Antenna 234 communicates with radio component 230 via communication link 232. Communication link 232 may be a receive link, a transmit link, or both. Radio component 230 may be configured to communicate via various wireless communication standards, including but not limited to 5G NR, LTE, LTE-A, GSM, UMTS, CDMA2000, Wi-Fi, etc.

[0092] Base station 102 may be configured to perform wireless communication using multiple wireless communication standards. In some cases, base station 102 may include multiple radios that enable base station 102 to communicate according to multiple wireless communication technologies. For example, as one possibility, base station 102 may include an LTE radio component for performing communication according to LTE and a 5G NR radio component for performing communication according to 5G NR. In this case, base station 102 may be capable of operating as both an LTE base station and a 5G NR base station. As another possibility, base station 102 may include a multi-mode radio component capable of performing communication according to any one of multiple wireless communication technologies (such as 5G NR and Wi-Fi, LTE and Wi-Fi, LTE and UMTS, LTE and CDMA2000, UMTS and GSM, etc.).

[0093] As further described subsequently herein, BS102 may include hardware and software components for implementing or supporting the specific implementation of the features described herein. The processor 204 of base station 102 may be configured to implement or support the implementation of part or all of the methods described herein, for example, by executing program instructions stored on a memory medium (such as a non-transitory computer-readable memory medium). Alternatively, processor 204 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. Alternatively (or in addition), in combination with one or more of the other components 230, 232, 234, 240, 250, 260, 270, the processor 204 of BS102 may be configured to implement or support the implementation of part or all of the features described herein.

[0094] In addition, as described herein, processor 204 may be composed of one or more processing elements. In other words, one or more processing elements may be included in processor 204. Therefore, processor 204 may include one or more integrated circuits (ICs) configured to perform the functions of processor 204. In addition, each integrated circuit may include circuits (such as a first circuit, a second circuit, etc.) configured to perform the functions of one or more processors 204.

[0095] Furthermore, as described herein, radio component 230 may be composed of one or more processing elements. In other words, one or more processing elements may be included in radio component 230. Therefore, radio component 230 may include one or more integrated circuits (ICs) configured to perform the functions of radio component 230. In addition, each integrated circuit may include circuits (such as a first circuit, a second circuit, etc.) configured to perform the functions of radio component 230.

[0096] Figure 3 : UE Block Diagram

[0097] Figure 3 An exemplary simplified block diagram of a communication device 106 according to some embodiments is shown. Note that Figure 3 the block diagram of the communication device is only one example of a possible communication device. According to an embodiment, the communication device 106 can be a user equipment (UE) device, a mobile device or mobile station, a wireless device or wireless station, a desktop computer or computing device, a mobile computing device (e.g., a laptop computer, notebook or portable computing device), a tablet computer, an unmanned aerial vehicle (UAV), a UAV controller (UAC), and / or a combination of devices, and other devices. As shown, the communication device 106 can include a set of components 300 configured to perform core functions. For example, the set of components can be implemented as a system on a chip (SOC), which can include parts for various purposes. Alternatively, the set of components 300 can be implemented as separate components or groups of components for various purposes. This set of components 300 can be (e.g., communicatively; directly or indirectly) coupled to various other circuits of the communication device 106.

[0098] For example, the communication device 106 can include various types of memories (e.g., including NAND flash memory 310), input / output interfaces such as connector I / F 320 (e.g., for connecting to a computer system; docking station; charging station; input devices such as a microphone, camera, keyboard; output devices such as a speaker; etc.), a display 360 that can be integrated with or external to the communication device 106, and cellular communication circuits 330 such as for 5G NR, LTE, GSM, etc., and short-range to medium-range wireless communication circuits 329 (e.g., Bluetooth TM and WLAN circuits). In some embodiments, the communication device 106 can include a wired communication circuit (not shown), such as a network interface card for Ethernet, for example.

[0099] The cellular communication circuits 330 can be (e.g., communicatively; directly or indirectly) coupled to one or more antennas, such as the antennas 335 and 336 shown. The short-range to medium-range wireless communication circuits 329 can also be (e.g., communicatively; directly or indirectly) coupled to one or more antennas, such as the antennas 337 and 338 shown. Alternatively, the short-range to medium-range wireless communication circuits 329, in addition to (e.g., communicatively; directly or indirectly) being coupled to the antennas 337 and 338 or as an alternative, can be (e.g., communicatively; directly or indirectly) coupled to the antennas 335 and 336. The short-range to medium-range wireless communication circuits 329 and / or the cellular communication circuits 330 can 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.

[0100] In some embodiments, as further described below, the cellular communication circuitry 330 may include dedicated receive chains for multiple RATs (including and / or coupled to (e.g., communicatively; directly or indirectly) dedicated processors and / or radio components) (e.g., a first receive chain for LTE and a second receive chain for 5G-NR). Additionally, in some embodiments, the cellular communication circuitry 330 may include a single transmit chain that may be switched between radio components dedicated to a particular RAT. For example, a first radio component may be dedicated to a first RAT, such as LTE, and may communicate with the dedicated receive chain as well as a transmit chain shared with additional radio components, such as a second radio component that may be dedicated to a second RAT (e.g., 5G NR) and may communicate with the dedicated receive chain as well as the shared transmit chain.

[0101] The communication device 106 may also include one or more user interface elements and / or be configured to work with one or more user interface elements. The user interface elements may include various elements such as a display 360 (which may be a touchscreen display), a keyboard (which may be a discrete keyboard or may be implemented as part of a touchscreen display), a mouse, a microphone and / or speaker, one or more cameras, one or more buttons, and / or any of various other elements capable of providing information to the user and / or receiving or interpreting user input.

[0102] The communication device 106 may also include one or more smart cards 345 having SIM (Subscriber Identity Module) functionality, such as one or more UICC cards (one or more Universal Integrated Circuit Cards) 345. Note that the term "SIM" or "SIM entity" is intended to include any of various types of SIM implementations or SIM functionality, such as one or more UICC cards 345, one or more eUICC, one or more eSIM, removable or embedded, etc. In some embodiments, the UE 106 may include at least two SIMs. Each SIM may execute one or more SIM applications and / or otherwise implement SIM functionality. Thus, each SIM may be a single smart card that may be embedded, e.g., soldered to a circuit board within the UE 106, or each SIM 345 may be implemented as a removable smart card. Thus, the SIM may be one or more removable smart cards (such as UICC cards sometimes referred to as "SIM cards"), and / or the SIM 345 may be one or more embedded cards (such as embedded UICC (eUICC) sometimes referred to as "eSIM" or "eSIM card"). In some embodiments (such as when the SIM includes an eUICC), one or more of the SIMs in the SIM may implement embedded SIM (eSIM) functionality; in such embodiments, a single SIM in the SIM may execute multiple SIM applications. Each SIM may include components such as a processor and / or memory; instructions for performing SIM / eSIM functionality may be stored in the memory and executed by the processor. In some embodiments, the UE 106 may include a combination of removable smart cards and fixed / non-removable smart cards (such as one or more eUICC cards implementing eSIM functionality) as needed. For example, the UE 106 may include a combination of two embedded SIMs, two removable SIMs, or one embedded SIM and one removable SIM. Various other SIM configurations are also contemplated.

[0103] As described above, in some embodiments, the UE 106 may include two or more SIMs. The inclusion of two or more SIMs in the UE 106 may allow the UE 106 to support two different telephone numbers and may allow the UE 106 to communicate on two corresponding or more respective networks. For example, a first SIM may support a first RAT such as LTE, and a second SIM 345 may support a second RAT such as 5G NR. Of course, other implementations and RATs are possible. In some embodiments, when the UE 106 includes two SIMs, the UE 106 may support the Dual SIM Dual Active (DSDA) function. The DSDA function may allow the UE 106 to be connected to two networks simultaneously (and use two different RATs), or may allow two connections supported by two different SIMs using the same or different RATs to be maintained simultaneously on the same or different networks. The DSDA function may also allow the UE 106 to receive voice calls or data traffic simultaneously on either telephone number. In certain embodiments, the voice call may be a packet-switched communication. In other words, Voice over LTE (VoLTE) technology and / or Voice over NR (VoNR) technology may be used to receive voice calls. In some embodiments, the UE 106 may support the Dual SIM Dual Standby (DSDS) function. The DSDS function may allow either of the two SIMs in the UE 106 to standby waiting for a voice call and / or a data connection. In DSDS, when a call / data is established on one SIM, the other SIM is no longer active. In some embodiments, the DSDx function (DSDA or DSDS function) may be implemented using a single SIM (e.g., eUICC) that executes multiple SIM applications for different carriers and / or RATs.

[0104] As shown, the SOC 300 may include a processor 302 and a display circuit 304. The processor may execute program instructions for the communication device 106, and the display circuit may perform graphics processing and provide a display signal to the display 360. One or more processors 302 may also be coupled to a Memory Management Unit (MMU) 340 (the MMU may be configured to receive addresses from one or more processors 302 and translate those addresses into locations in a memory (e.g., memory 306, Read Only Memory (ROM) 350, NAND flash memory 310)) and / or be coupled to other circuits or devices (such as, the display circuit 304, short-range to medium-range wireless communication circuit 329, cellular communication circuit 330, connector I / F 320, and / or the 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.

[0105] As described above, the communication device 106 may be configured to communicate using wireless and / or wired communication circuitry. The communication device 106 may be configured to perform the method for more flexible triggering of an aperiodic SRS transmission by the UE as further described herein.

[0106] As described herein, the communication device 106 may include hardware and software components for implementing the above-described features of the communication device 106 to send a scheduling profile for power saving to the network. For example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium), the processor 302 of the communication device 106 may be configured to implement some or all of the features described in the present invention. Alternatively (or in addition), the processor 302 may be configured as a programmable hardware element, such as an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit). Alternatively (or in addition), in combination with one or more of the other components 300, 304, 306, 310, 320, 329, 330, 340, 345, 350, 360, the processor 302 of the communication device 106 may be configured to implement some or all of the features described herein.

[0107] Furthermore, as described in the present invention, the processor 302 may include one or more processing elements. Thus, the processor 302 may include one or more integrated circuits (ICs) configured to perform the functions of the processor 302. In addition, each integrated circuit may include circuitry (e.g., a first circuit, a second circuit, etc.) configured to perform one or more of the functions of the processor 302.

[0108] Further, as described herein, the cellular communication circuitry 330 and the short-range to medium-range wireless communication circuitry 329 may each include one or more processing elements. In other words, one or more processing elements may be included in the cellular communication circuitry 330, and similarly, one or more processing elements may be included in the short-range to medium-range wireless communication circuitry 329. Thus, the cellular communication circuitry 330 may include one or more integrated circuits (ICs) configured to perform the functions of the cellular communication circuitry 330. In addition, each integrated circuit may include circuitry (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of the cellular communication circuitry 330. Similarly, the short-range to medium-range wireless communication circuitry 329 may include one or more ICs configured to perform the functions of the short-range to medium-range wireless communication circuitry 329. In addition, each integrated circuit may include circuitry (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of the short-range to medium-range wireless communication circuitry 329.

[0109] Figure 4 : Block diagram of cellular communication circuitry

[0110] Figure 4Shows an exemplary simplified block diagram of a cellular communication circuit according to some embodiments. Note that Figure 4 The block diagram of the cellular communication circuit is only one example of a possible cellular communication circuit. According to an embodiment, the cellular communication circuit 430 may be included in a communication device such as the communication device 106 described above. As described above, in addition to other devices, the communication device 106 may be a user equipment (UE) device, a mobile device or mobile station, a wireless device or wireless station, a desktop computer or computing device, a mobile computing device (e.g., a laptop computer, notebook or portable computing device), a tablet computer, and / or a combination of devices.

[0111] The cellular communication circuit 430 may be (e.g., communicatively; directly or indirectly) coupled to one or more antennas, such as the antennas 435a - 435b and 436 shown in ( Figure 4 ) In some embodiments, the cellular communication circuit 330 may include dedicated receive chains for multiple RATs (including and / or coupled to (e.g., communicatively; directly or indirectly) dedicated processors and / or radio components) (e.g., a first receive chain for LTE and a second receive chain for 5G - NR). For example, as Figure 4 shown, the cellular communication circuit 430 may include a modem 410 and a modem 420. The modem 410 may be configured for communication according to a first RAT (e.g., such as LTE or LTE - A), and the modem 420 may be configured for communication according to a second RAT (e.g., such as 5G NR).

[0112] As shown, the modem 410 may include one or more processors 412 and a memory 416 in communication with the processors 412. The modem 410 may communicate with a radio frequency (RF) front - end 480. The RF front - end 480 may include circuitry for transmitting and receiving radio signals. For example, the RF front - end 480 may include a receive circuit (RX) 482 and a transmit circuit (TX) 484. In some embodiments, the receive circuit 482 may communicate with a downlink (DL) front - end 450, which may include circuitry for receiving radio signals via the antenna 435a.

[0113] Similarly, the modem 420 may include one or more processors 422 and a memory 426 in communication with the processors 422. The modem 420 may communicate with an RF front - end 490. The RF front - end 490 may include circuitry for transmitting and receiving radio signals. For example, the RF front - end 490 may include a receive circuit 492 and a transmit circuit 494. In some embodiments, the receive circuit 492 may communicate with a DL front - end 460, which may include circuitry for receiving radio signals via the antenna 435b.

[0114] In some embodiments, switch 470 may couple transmission circuit 494 to uplink (UL) front end 472. Additionally, switch 470 may couple transmission circuit 494 to UL front end 472. UL front end 472 may include circuitry for transmitting radio signals via antenna 436. Thus, when cellular communication circuit 430 receives an instruction to transmit according to a first RAT (e.g., supported via modem 410), switch 470 may be switched to a first state that permits modem 410 to transmit signals according to the first RAT (e.g., via a transmission chain including transmission circuit 434 and UL front end 472). Similarly, when cellular communication circuit 430 receives an instruction to transmit according to a second RAT (e.g., supported via modem 420), switch 470 may be switched to a second state that permits modem 420 to transmit signals according to the second RAT (e.g., via a transmission chain including transmission circuit 494 and UL front end 472).

[0115] In some embodiments, cellular communication circuit 430 may be configured to perform methods for more flexibly triggering aperiodic SRS transmissions by a UE as further described herein.

[0116] As described herein, modem 410 may include hardware and software components for implementing the above-described features or for time-division multiplexing UL data for NSANR operation and various other techniques described herein. For example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium), processor 412 may be configured to implement some or all of the features described herein. Alternatively (or in addition), processor 412 may be configured as a programmable hardware element, such as an FPGA (field programmable gate array) or as an ASIC (application specific integrated circuit). Alternatively (or in addition), in combination with one or more of the other components 430, 432, 434, 450, 470, 472, 435, and 436, processor 412 may be configured to implement some or all of the features described herein.

[0117] Furthermore, as described herein, processor 412 may include one or more processing elements. Thus, processor 412 may include one or more integrated circuits (ICs) configured to perform the functions of processor 412. Additionally, each integrated circuit may include circuitry (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of processor 412.

[0118] As described herein, modem 420 may include hardware and software components for implementing the above-described features for communicating a scheduling profile for power savings to the network and various other techniques described herein. For example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium), processor 422 may be configured to implement some or all of the features described herein. Alternatively (or in addition), processor 422 may be configured as a programmable hardware element, such as an FPGA (field programmable gate array) or as an ASIC (application specific integrated circuit). Alternatively (or in addition), in combination with one or more of the other components 440, 442, 444, 450, 470, 472, 435, and 436, processor 422 may be configured to implement some or all of the features described herein.

[0119] In addition, as described herein, processor 422 may include one or more processing elements. Thus, processor 422 may include one or more integrated circuits (ICs) configured to perform the functions of processor 422. In addition, each integrated circuit may include circuitry (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of processor 422.

[0120] Figure 5 : UE Baseband Processor Architecture

[0121] Figure 5 An example of a baseband processor architecture for a UE (e.g., such as UE 106) according to some embodiments is shown. Figure 5The baseband processor architecture 500 described in can be implemented on one or more radio components (e.g., radio components 329 and / or 330 as described above) and / or modems (e.g., modems 410 and / or 420) as described above. As shown, the non-access stratum (NAS) 510 can include a 5G NAS 520 and a legacy NAS 550. The legacy NAS 550 can include a communication connection with a legacy access stratum (AS) 570. The 5G NAS 520 can include communication connections with both a 5G AS 540 and a non-3GPP AS 530 as well as a Wi-Fi AS 532. The 5G NAS 520 can include functional entities associated with both access strata. Thus, the 5G NAS 520 can include multiple 5G MM entities 526 and 528 and 5G session management (SM) entities 522 and 524. The legacy NAS 550 can include functional entities such as a short message service (SMS) entity 552, an evolved packet system (EPS) session management (ESM) entity 554, a session management (SM) entity 556, an EPS mobility management (EMM) entity 558, and a mobility management (MM) / GPRS mobility management (GMM) entity 560. Additionally, the legacy AS 570 can include functional entities such as an LTE AS 572, a UMTS AS 574, and / or a GSM / GPRS AS 576.

[0122] Thus, the baseband processor architecture 500 allows for a common 5G-NAS for both 5G cellular and non-cellular (e.g., non-3GPP access). Note that, as shown, 5G MM can maintain separate connection management and registration management state machines for each connection. Additionally, a device (e.g., UE 106) can register with a single PLMN (e.g., 5GCN) using both 5G cellular access and non-cellular access. Further, a device can be in a connected state in one access and in an idle state in another access, and vice versa. Finally, there can be common 5G-MM procedures (e.g., registration, deregistration, identification, authentication, etc.) for both accesses.

[0123] Note that in various embodiments, one or more of the above-described functional entities of the 5G NAS and / or 5G AS can be configured to perform methods for, e.g., flexibly triggering non-periodic SRS transmissions by a UE as further described herein.

[0124] Non-periodic sounding reference signal

[0125] In the current cellular communication system, a UE can be configured to transmit sounding reference signals (SRS) to a base station periodically, semi-persistently, or aperiodically on an uplink channel. The base station uses the SRS signals to evaluate the uplink channel quality between the UE and the base station. More specifically, in a cellular system, the base station typically allocates only a portion of the total system bandwidth to a specific UE at any given time. The base station can use the received SRS signals to determine which portion of the total system bandwidth has the best relative uplink channel quality. In other words, the base station can use the SRS signals received from each UE to allocate the "best" frequency region to each of these UEs based on the uplink channel quality determined from the received SRS signals.

[0126] The UE can transmit SRS signals for various purposes or use cases, including antenna switching, beam management, codebook-based and non-codebook-based purposes, and for carrier switching. Antenna switching refers to the process by which the UE can cycle through transmitting SRS signals on each of its multiple antennas so that the base station can evaluate the downlink channel quality via the uplink channel quality estimation for each antenna. The UE can also transmit SRS for beam management purposes, for example, to allow the base station to evaluate the best beam orientation for improved uplink channel quality. The non-codebook-based use case refers to the situation where, assuming the uplink and downlink channels are similar (e.g., in the TDD case), the base station uses the received SRS to evaluate the downlink channel and helps select a codebook for downlink communication. The term "carrier switching" refers to the case where one or more UEs can switch to using a different component carrier or a different bandwidth part when communicating with the base station.

[0127] The UE can be configured to transmit SRS signals at predefined intervals (i.e., according to a set period). However, the base station can also issue a specific aperiodic request to the UE to transmit SRS signals. The base station's request for aperiodic SRS can take the form of an SRS trigger transmitted from the base station to the UE. The base station can decide to send an aperiodic SRS trigger due to the detection of a degradation in the uplink channel quality or other reasons.

[0128] In the current specific implementation, the base station can perform an aperiodic SRS (AP-SRS) trigger in various DCI formats, including UL DCI formats 0_1 and 0_2, DL DCI formats 1_1 and 1_2, and DL format 2_3. The downlink control information has multiple fields configured during RRC, as defined in 3GPP technical specification 38.212. The relevant fields in DCI format 0_1 are described below, noting that DCI format 0_2 is similar.

[0129] According to Section 7.3.1.1.2 of 3GPP Technical Specification 38.212, DCI format 0_1 is used to schedule one or more PUSCHs in a cell or to indicate to the UE a configured grant (CG) PUSCH. The following information (among other information) is transmitted by DCI format 0_1 with a CRC scrambled by C-RNTI or CS-RNTI or SP-CSI-RNTI or MCS-C-RNTI:

[0130] 1) Time domain resource allocation - 0, 1, 2, 3, 4, 5, or 6 bits

[0131] 2) SRS resource indicator

[0132] 3) SRS request - 2 bits, as defined in Table 7.3.1.1.2-24, for UEs not configured with supplementaryUplink in ServingCellConfig in the cell; 3 bits, for UEs configured with supplementaryUplink in ServingCellConfig in the cell, where the first bit is the non-SUL / SUL indicator as defined in Table 7.3.1.1.1-1, and the second and third bits are defined by Table 7.3.1.1.2-24. According to Clause 6.1.1.2 of [6, TS 38.214], this bit field may also indicate the associated CSI-RS.

[0133] 4) CSI request - 0, 1, 2, 3, 4, 5, or 6 bits, determined by the higher layer parameter reportTriggerSize.

[0134] 5) UL-SCH indicator - 0 or 1 bit.

[0135] Note that it is not desirable for the UE to receive downlink control information of DCI format 0_1 or DCI format 0_2 with the UL-SCH indicator being "0" and the CSI request all being zero.

[0136] In addition, the special DCI format 2_3 can be used to trigger AP-SRS for multiple UEs in a cell. Currently, DCI format 2_3 is only used for SRS carrier switching, i.e., when the UE switches to a different component carrier.

[0137] The current method for triggering aperiodic SRS lacks sufficient flexibility to accommodate all the various scenarios where aperiodic SRS may be desired. Therefore, an improvement in the art is desired.

[0138] Figure 6A and Figure 6B : Flexible aperiodic SRS triggering

[0139] The various embodiments described herein relate to improved methods for allowing a base station to trigger a UE-generated aperiodic SRS.

[0140] Figure 6A and Figure 6B is a flowchart showing operations according to one embodiment, whereby the base station has increased flexibility when transmitting an SRS trigger to a UE. Figure 6A shows base station operations, and Figure 6B shows UE operations

[0141] As Figure 6A shown, at 602, the base station may determine that the UE should transmit an aperiodic sounding reference signal (SRS) to the base station. This determination may be made for any of a variety of reasons, such as detection of signal quality degradation on the uplink channel, etc.

[0142] At 604, the base station may transmit downlink control information (DCI) to the UE. The downlink control information may include one or more parameter fields set to specific values. For example, the downlink control information may include a first parameter field set to a first specific value and a second parameter field set to a second specific value. The first parameter field set to the first specific value and the second parameter field set to the second specific value may together indicate to the UE that the UE should transmit an aperiodic SRS to the base station without any accompanying data. Examples of these fields include the CSI request field and the UL-SCH indicator field, as well as other possible fields.

[0143] More specifically, in one embodiment, the base station (e.g., gNB) is allowed to schedule the fields of DCI formats 0_1 and 0_2 as follows:

[0144] “UL-SCH indicator” field: 0

[0145] “CSI request” field: 0;

[0146] “SRS request” field: non-zero

[0147] When the above fields have the values indicated above, the expected behavior of the UE is as follows:

[0148] The UE will not transmit on the physical uplink shared channel (PUSCH)

[0149] The UE will transmit an AP-SRS corresponding to the non-zero value in the “SRS request” field in the DCI.

[0150] Thus, in some embodiments, for DCI formats 0_1 and 0_2, the base station may indicate an aperiodic SRS trigger while also specifying a uplink shared channel (UL-SCH) indicator of 0 and a channel state information (CSI) request all zeros. When the UE receives the downlink control information of DCI formats 0_1 and 0_2 and the (UL-SCH) indicator is set to 0 and the channel state information (CSI) request is all zeros, the combination of values may indicate that no uplink data is being requested on the uplink shared channel. Additionally, the SRS request may have a non-zero value, which indicates to the UE an aperiodic SRS trigger.

[0151] As Figure 6B shown, in 606, the UE receives DCI with a specified configuration (the configuration in 604) and may interpret it as an AP-SRS trigger, and the UE will not transmit any accompanying data on the PUSCH. In other words, the UE is configured to infer that when it receives the downlink control information with the configuration as described above in 804, the UE interprets it as an SRS trigger and no uplink data is requested on the uplink shared channel.

[0152] In 608, the UE may transmit an SRS in response to the specified DCI configuration (i.e., based on the non-zero value in the SRS request field). Thus, here the UE has interpreted the received DCI configuration as meaning to generate an SRS and also meaning that no accompanying data needs to be generated on the PUSCH.

[0153] In some embodiments, for DCI formats 0_1 and 0_2, the following DCI formats are determined by the UE to be invalid:

[0154] "CSI request" field: 0

[0155] "UL-SCH indicator" field: 0

[0156] "SRS request" field: 0

[0157] In another embodiment, the base station (e.g., gNB) is allowed to schedule the fields of DCI formats 0_1 and 0_2 as follows:

[0158] "CSI request" field: 0

[0159] "UL-SCH indicator" field: 0

[0160] "SRS request" field: non-zero

[0161] The following fields in the DCI may be interpreted by the UE as having the following new meanings:

[0162] "Time domain resource allocation" field: slot offset of AP-SRS

[0163] "SRS Resource Indicator" field: QCL (beam) of AP-SRS

[0164] Therefore, the "Time Domain Resource Allocation" field can be re-specified with a new meaning: now indicating the time slot offset of AP-SRS. In addition, the "SRS Resource Indicator" field can be re-specified with a new meaning: now indicating the quasi-co-location (QCL) or beam of AP-SRS. Note that other fields can be used to replace or supplement the above fields.

[0165] Aperiodic SRS trigger for fallback DCI format

[0166] In another embodiment, the base station can use DCI format 2_3 to trigger any type of aperiodic SRS transmission. In other words, in this embodiment, DCI format 2_3 can be used to trigger aperiodic SRS transmissions for any of various purposes, including codebook-based, non-codebook-based, and beam management, as well as antenna switching and carrier switching. Therefore, the base station can generate and transmit downlink control information (DCI) of format 2_3 and use this DCI format 2_3 to specify an aperiodic SRS transmission to the UE for any of various purposes. When the UE receives DCI of format 2_3 and is configured to indicate an SRS trigger, the UE can respond by transmitting the SRS with an appropriate time slot offset.

[0167] Figure 7A and Figure 7B : Aperiodic SRS trigger for UE group

[0168] In the current cellular standard, DCI format 2_3 is used to trigger aperiodic SRS for a group of UEs. However, additional flexibility is desired, that is, it is desired to have another DCI format that can be used to trigger SRS for multiple UEs. Therefore, in another embodiment, the base station can utilize a new DCI format that can be used to trigger aperiodic SRS for a group of UEs. In other words, this new DCI format can be used to trigger each UE in a group of UEs to generate aperiodic SRS and may have reduced latency compared to the previous format.

[0169] Figure 7A and Figure 7B is a flowchart showing the operation of the base station to configure multiple UEs in a group and then use this new DCI format to trigger AP-SRS for each UE in the group or each UE in multiple groups. This can provide higher efficiency. For example, the base station can use a single DCI message to more effectively trigger SRS in a group of UEs. Figure 7A shows the base station operation, and Figure 7B shows the UE operation.

[0170] As shown in the figure, in 731, during RRC configuration, the base station may configure each of a plurality of UEs to belong to a UE group. In other words, for each UE, during RRC configuration, the network (or the base station) may configure the group to which the corresponding UE belongs. Assigning a plurality of UEs to a group allows the use of a new DCI format, which can be used to target or address one or more UE groups for SRS triggering. For each UE in the group, the AP-SRS trigger status may be indicated independently, or alternatively, the same AP-SRS trigger status may be indicated for all UEs in the same group in order to reduce the DCI size.

[0171] Later, during UE operation, at 732, the base station may determine that a group of UEs should generate SRS signals. As described above, this determination may be based on an assessment of the uplink channel quality degradation of individual UEs in the group, as well as other possible reasons.

[0172] At 734, the base station may create and transmit a DCI message that contains an SRS trigger and includes a group identifier that identifies the UE group for which the SRS trigger is desired.

[0173] The cyclic redundancy check (CRC) of the new DCI format may be scrambled using aperiodic sounding reference signal - radio network temporary identifier (SRS-RNTI), which is common to all UEs in the group. This aperiodic SRS-RNTI can be used to identify the UEs in the targeted group. Thus, when each UE in the group receives DCI information with the aperiodic SRS-RNTI, each UE can identify the AP-SRS-RNTI, and the identification of the AP-SRS-RNTI along with the new DCI format itself indicates to the UE that it should generate an aperiodic SRS.

[0174] Alternatively or in addition, the cyclic redundancy check (CRC) of the new DCI format may be scrambled using a group aperiodic SRS-RNTI that is different for each UE group. This group AP-SRS-RNTI can be used to identify the UEs in the targeted group.

[0175] The DCI message transmitted by the base station may include information identifying a plurality of UE groups, where each group includes a plurality of UEs. Thus, the new DCI format is not limited to providing an SRS trigger to a single group, but can target or identify multiple groups, where each group itself includes a plurality of UEs.

[0176] Figure 8Two different UE groups are shown, and a new DCI format for addressing multiple UE groups is also shown. As shown, in the case where a DCI message is targeted at two separate groups, the DCI message may include a first part for group 1 and a second part for group 2. Each corresponding part may include the AP-SRS trigger status for each UE in the group. In other words, for each group part, the DCI message may include a sub-part for each UE that independently indicates the AP-SRS trigger status information for each UE in the corresponding group.

[0177] Figure 7B UE operation is shown. As shown, at 736, each UE (or most UEs) in the group receives a DCI message with an RNTI that identifies the group to which the UE belongs. The UE may process the information in the DCI message and, specifically, may locate and process the AP-SRS trigger status specific to the corresponding UE.

[0178] In 738, each UE may then transmit an SRS to the base station in response to receiving a DCI with a group RNTI.

[0179] Aperiodic SRS Trigger for Fallback DCI Format

[0180] In another embodiment, the aperiodic SRS may be triggered by a large number of DCI formats (e.g., more DCI formats than currently allowed by the standard). More specifically, an SRS request field may be introduced for the "fallback" DCI format 0_0 for the uplink and DCI format 1_0 for the downlink. In this embodiment, an AP-SRS field is now included or introduced in the downlink control information for DCI formats 0_0 and 1_0.

[0181] The following is some background on DCI formats. Current cellular standards allow for multiple DCI formats. For regular (or non-fallback) DCI formats, the size and bit width of each field are RRC-configurable. However, there is a possibility that the RRC configuration may have some ambiguity or that the UE may not correctly interpret the RRC configuration. The fallback DCI 0_0 and 1_0 formats are statically defined in the specification and are used by the base station to communicate with the UE as a "last resort" or as a mechanism to ensure that the RRC configuration between the base station and the UE remains in sync. These DCI formats are called "fallback DCI" because they are DCI formats that the base station can always use to communicate with the UE, regardless of any errors or ambiguities in the previous RRC configuration. By including an AP-SRS field in the fallback DCI format, this helps ensure that the base station can always trigger the AP-SRS, regardless of any previous issues with the RRC configuration or other DCI format configurations.

[0182] Multi-TRP Aperiodic SRS Trigger

[0183] In many cases, a UE operates in a multi-transmit receive point (multi-TRP) scenario, where the UE communicates with multiple base stations. In a multi-TRP scenario, the UE may desire (or be instructed) to dynamically transmit an aperiodic SRS to one of these TRPs. When this occurs, the UE may need to dynamically change its transmit beam. However, the current transmit beam of the UE is statically configured as the spatialRelationInfo in the SRS-Resource during RRC. The UE may also need to dynamically change its open-loop power control. However, the current power control is statically configured by RRC in the SRS-ResourceSet. Therefore, improvements in the art are desired.

[0184] In some embodiments, for AP-SRS, the base station may use DCI to dynamically change the beam and / or spatial relation of the AP-SRS. This change information may be indicated as: 1) a separate SRI, i.e., an SRS resource indicator; 2) a separate spatial relation configuration; or 3) a separate TCI (transmission configuration indicator)

[0185] In some embodiments, for AP-SRS, DCI or MAC-CE may be allowed to dynamically change the open-loop power control. This may include settings including one or more or all of the following: α; p0, pathlossReferenceRS.

[0186] Therefore, the method may use DCI or MAC-CE to optimize the power for AP-SRS to better meet the needs of the base station. This may allow the UE to find the best Tx / Rx relationship corresponding to a specific base station.

[0187] It is well known that the use of personally identifiable information should follow privacy policies and practices that are recognized as meeting or exceeding industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of inadvertent or unauthorized access or use, and the nature of the authorized use should be clearly explained to the user.

[0188] Embodiments of the present disclosure may be implemented in any of a variety of forms. For example, some embodiments may be implemented as a computer-implemented method, a computer-readable memory medium, or a computer system. Other embodiments may be implemented using one or more custom-designed hardware devices such as an ASIC. Other embodiments may be implemented using one or more programmable hardware elements such as an FPGA.

[0189] In some embodiments, a non-transitory computer-readable memory medium may be configured such that it stores program instructions and / or data, where if executed by a computer system, the program instructions cause the computer system to perform a method, such as any of the method embodiments described herein, or any combination of the method embodiments described herein, or any subset of any of the method embodiments described herein, or any combination of such subsets.

[0190] In some embodiments, a device (e.g., UE 106) may be configured to include a processor (or a set of processors) and a memory medium, where the memory medium stores program instructions, where the processor is configured to read and execute the program instructions from the memory medium, where the program instructions are executable to implement any of the various method embodiments described herein (or any combination of the method embodiments described herein, or any subset of any of the method embodiments described herein, or any combination of such subsets). The device may be implemented in any of a variety of forms.

[0191] Any of the methods described herein for operating a UE can form the basis for a corresponding method for operating a base station by interpreting each message / signal X received by the user equipment (UE) in the downlink as a message / signal X transmitted by the base station, and interpreting each message / signal Y transmitted by the UE in the uplink as a message / signal Y received by the base station.

[0192] While the above embodiments have been described in considerable detail, many variations and modifications will become apparent to those skilled in the art once the above disclosure is fully understood. The present disclosure is intended that the following claims be construed to cover all such variations and modifications.

Claims

1. A wireless communication method, comprising: Transmitting downlink control information (DCI) to a user equipment (UE), wherein when the DCI includes at least one first parameter field, at least one second parameter field, and at least one third parameter field, the DCI includes an indication to transmit an aperiodic sounding reference signal (SRS), where the at least one first parameter field is set to indicate that no uplink shared channel (UL-SCH) data is requested from the UE, the at least one second parameter field is set to indicate that no channel state information (CSI) is requested from the UE, and the at least one third parameter field requests transmission of an aperiodic SRS to a base station, wherein when the UE is communicating with multiple transmit receive points (TRP), the DCI further includes an indication to the UE to adjust its open-loop power control and perform at least one of changing a beam for transmitting the aperiodic SRS or changing a spatial relationship of the aperiodic SRS; and Receiving an aperiodic SRS signal from the UE, wherein the aperiodic SRS signal is received from the UE in response to transmission of the DCI.

2. The wireless communication method according to claim 1, wherein the downlink control information has a DCI format 0_1 or 0_2.

3. The wireless communication method according to claim 2, wherein the at least one first parameter field includes: an uplink shared channel (UL-SCH) indicator set to 0; wherein the at least one second parameter field includes a channel state information (CSI) request field set to all 0s; wherein the at least one third parameter field includes an SRS request field having a non-zero value; wherein the DCI indicates to the UE that the UE should transmit an aperiodic SRS corresponding to the non-zero value in the SRS request field to the base station, and wherein no request is made to transmit uplink data on the uplink shared channel.

4. The wireless communication method according to claim 1, wherein when the DCI includes a channel state information (CSI) request field with a value of 0, an uplink shared channel indicator (UL-SCH) field with a value of 0, and an SRS request field with a value of 0, the DCI is interpreted by the UE as an invalid DCI.

5. The wireless communication method according to claim 1, wherein the DCI includes a time domain resource allocation field having a value specifying a time slot offset of the aperiodic SRS.

6. The wireless communication method according to claim 5, wherein the DCI includes an SRS resource indicator field that specifies beam information that can be used by the UE when transmitting the aperiodic SRS to the base station.

7. The wireless communication method according to claim 1, further comprising: Determining that the UE should transmit an aperiodic sounding reference signal (SRS) to the base station; and Transmitting the DCI in response to determining that the UE should transmit the aperiodic SRS to the base station.

8. The wireless communication method according to claim 1, further comprising: Transmit downlink control information (DCI) having one of DCI format 0_0 or 0_1 and including an SRS request field that can be used to trigger the UE to transmit SRS.

9. A wireless communication method, comprising: Receiving downlink control information DCI from a base station; Processing the DCI received from the base station, when the DCI includes at least one first parameter field, at least one second parameter field, and at least one third parameter field, the DCI includes an indication to transmit an aperiodic sounding reference signal SRS, wherein the at least one first parameter field is set to indicate that no uplink shared channel UL-SCH data is requested from a user equipment UE, the at least one second parameter field is set to not request channel state information CSI from the UE, and the at least one third parameter field requests transmission of an aperiodic SRS to the base station, wherein, when the UE is communicating with multiple transmit receive points TRP, the DCI further includes an indication to the UE to adjust its open-loop power control and perform at least one of changing the beam for transmitting the aperiodic SRS or changing the spatial relationship of the aperiodic SRS; and Transmitting an aperiodic SRS transmission to the base station in response to the reception of the DCI.

10. The wireless communication method according to claim 9, further comprising: Wherein the UE does not transmit data on a physical uplink shared channel (PUSCH) in response to receiving the DCI in which the UL-SCH is set to 0 and the CSI request field is set to 0.

11. The wireless communication method according to claim 9, Wherein the DCI has DCI format 0_1 or 0_2.

12. The wireless communication method according to claim 9, further comprising: Receiving a second DCI from the base station, wherein when the downlink control information includes a UL-SCH indicator set to 0, a CSI request field set to 0, and an SRS request field having a zero value, the method further comprises: Interpreting the DCI as an invalid DCI.

13. The wireless communication method according to claim 9, Wherein the DCI includes a time domain resource allocation field having a value specifying a time slot offset of the aperiodic SRS.

14. The wireless communication method according to claim 9, Wherein the DCI includes an SRS resource indicator field that specifies beam information that can be used by the UE when transmitting the aperiodic SRS to the base station.

15. A wireless communication device, comprising: A processor configured to perform the method according to any one of claims 1 to 8 when executing instructions stored in a memory.

16. The wireless communication device according to claim 15, further comprising: One or more antennas; And Radio components operably coupled to the processor.

17. A wireless communication device, comprising: A processor configured to perform the method according to any one of claims 9 to 14 when executing instructions stored in a memory.

18. The wireless communication device according to claim 17, further comprising: At least one antenna; And A radio component operably coupled to the processor for communicating with a cellular network.

19. A non-transitory computer-readable storage medium storing program instructions that can be executed by one or more processors to cause a base station (BS) to perform the method according to any one of claims 1 to 8.

20. A non-transitory computer-readable storage medium storing program instructions that can be executed by one or more processors to cause a user equipment (UE) to perform the method according to any one of claims 9 to 14.

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