Method and device for saving network energy by closing transmission chain

Abstract

In one embodiment, a method includes transmitting a first set of one or more probe messages to a UE, the first set of one or more probe messages including a set of reference signals. The method includes receiving a first channel state information (CSI) report from the UE in response to a first set of one or more sounding messages, the first CSI report including a first CSI derived from measurements of a reference signal set; the method includes transmitting a second set of one or more sounding messages to the UE, the second set of one or more sounding messages including a subset of the reference signals. The method also includes receiving, in response to a second set of one or more probe messages, a second CSI report comprising a second CSI derived from the measurement of the subset of reference signals.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based upon and claims priority to U.S. patent application No. 63 / 396,457 filed on August 9, 2022, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates generally to communication systems, and more particularly to methods and apparatus for saving network energy by shutting down transmission chains. Background Art

[0004] In a conventional multiple-input and multiple-output (MIMO) system, multiple ports (e.g., channel state information reference signal (CSI-RS) ports) or data streams can be mapped to multiple transmit radio distribution units (TXRUs). This operation can be called port virtualization and can be considered as digital precoding. The output of the TXRU can then be mapped to antenna elements in the analog domain through TXRU virtualization. The output of the TXRU can be mapped to a set of co-polarized antenna elements through analog phase shifters or variable gain amplifiers. The terms transmit chain and TXRU can be used interchangeably. The TXRU may include power amplifiers, filters, digital / analog converters, etc. Since these components consume most of the power in the gNB, shutting down the TXRU can be used to save energy in the network.

[0005] Turning off transmit antenna chains or antenna elements can be performed by the gNB or network implementation, where turning off transmit chains results in a reduction in transmit energy from the base station. However, since turning off transmit chains is performed without UE coordination, the energy savings may be limited or the impact on UE performance may be large. In particular, the lack of UE coordination cannot ensure that those UEs that are most affected by the loss of received power can maintain acceptable communication performance. In addition, the inability to dynamically turn on / off base station components can result in non-optimal energy savings and performance losses.

[0006] This article describes some improvements that may also be applicable to other multiple access technologies and the telecommunications standards that employ them. Summary of the invention

[0007] The following briefly summarizes one or more embodiments of the present disclosure in order to provide a basic understanding of such embodiments. This summary is not an exhaustive overview of all contemplated embodiments, is not intended to identify the key or decisive elements of all embodiments, and is not intended to define the scope of any or all embodiments. Its sole purpose is to introduce some concepts of one or more embodiments of the present disclosure in a simplified form as a prelude to a more detailed description later.

[0008] The present disclosure discloses a method, an apparatus, and a non-transitory computer-readable medium for saving network energy by shutting down a transmission chain.

[0009] According to an exemplary embodiment, a method performed by at least one processor of a base station includes sending a first set of one or more sounding messages to a UE in a first state, the first set of one or more sounding messages including a reference signal set. The method also includes receiving a first channel state information (CSI) report from the UE in response to the first set of one or more sounding messages, the report including a first CSI obtained from a measurement of the reference signal set. The method also includes sending a second set of one or more sounding messages to the UE in a second state, the second set of one or more sounding messages including a subset of reference signals. The method also includes receiving a second CSI report in response to the second set of one or more sounding messages, the report including a second CSI obtained from a measurement of the subset of reference signals.

[0010] According to an exemplary embodiment, an apparatus includes at least one memory configured to store computer program code; and at least one processor configured to access the at least one memory and operate according to the instructions of the computer program code. The computer program code includes a first sending code configured to cause at least one of the at least one processor to send a first set of one or more sounding messages to a UE in a first state, the first set of one or more sounding messages including a reference signal set. The computer program code includes a first receiving code configured to cause at least one of the at least one processor to receive a first channel state information (CSI) report from the UE in response to the first set of one or more sounding messages, the first CSI report including a first CSI obtained from a measurement of a reference signal set. The computer program code includes a second sending code configured to cause at least one of the at least one processor to send a second set of one or more sounding messages to the UE in a second state, the second set of one or more sounding messages including a subset of reference signals. The computer program code includes receiving a second CSI report in response to the second set of one or more sounding messages, the second CSI report including a second CSI obtained from a measurement of a subset of reference signals.

[0011] According to an exemplary embodiment, a non-transitory computer-readable medium stores instructions, which, when executed by a processor in a base station, cause the processor to perform a method, the method comprising: sending a first group of one or more detection messages to a UE in a first state, the first group of one or more detection messages including a reference signal set. The method also includes: receiving a first channel state information (CSI) report from the UE in response to the first group of one or more detection messages, the report including a first CSI obtained from a measurement of a reference signal set. The method also includes: sending a second group of one or more detection messages to the UE in a second state, the second group of one or more detection messages including a subset of reference signals. The method also includes: receiving a second CSI report in response to the second group of one or more detection messages, the report including a second CSI obtained from a measurement of a subset of reference signals.

[0012] Additional embodiments will be set forth in the description which follows and, in part, will be apparent from the description, and / or may be learned by practice of embodiments presented in the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and other aspects, features and aspects of the embodiments of the present disclosure will be clearly seen from the following description in conjunction with the accompanying drawings, in which:

[0014] Figure 1 is a diagram of an example network device according to various embodiments of the present disclosure.

[0015] Figure 2 is a schematic diagram of an example wireless communication system according to various embodiments of the present disclosure.

[0016] Figure 3 is an example time series diagram illustrating a normal state and a time hopping window according to various embodiments of the present disclosure.

[0017] Figure 4 is an example time series diagram illustrating time hopping windows according to various embodiments of the present disclosure.

[0018] Figure 5 is an example time series diagram illustrating aperiodic activation of energy conservation states according to various embodiments of the present disclosure.

[0019] Figure 6 is an example flow chart of one embodiment of a process for performing network power conservation by shutting down transmission chains.

[0020] Figure 7 is an example flow chart of one embodiment of a process for probing a UE. DETAILED DESCRIPTION

[0021] The following detailed description of example embodiments refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements.

[0022] The foregoing disclosure provides explanation and description, but is not intended to be exhaustive or to limit the implementation mode to the disclosed precise form. In view of the foregoing disclosure, modifications and variations can be made, or can be obtained from the practice of the implementation mode. In addition, one or more features or components of an embodiment can be incorporated into or combined with another embodiment (or one or more features of another embodiment). In addition, in the flow charts and operation descriptions provided below, it should be understood that one or more operations can be omitted, one or more operations can be added, one or more operations can be performed simultaneously (at least in part), and the order of one or more operations can be switched.

[0023] It will be apparent that the systems and / or methods described herein may be implemented in various forms of hardware, firmware, or a combination of hardware and software. The actual dedicated control hardware or software code used to implement these systems and / or methods does not limit the implementation. Thus, the operation and behavior of the systems and / or methods are described herein without reference to specific software code—it should be understood that software and hardware may be designed to implement the systems and / or methods based on the description herein.

[0024] Although particular combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of possible implementations. In fact, many of these features may be combined in ways not explicitly recited in the claims and / or disclosed in the specification. Although each dependent claim listed below may only directly depend on one claim, the disclosure of possible implementations includes each dependent claim in combination with every other claim in the claim set.

[0025] Unless explicitly stated, any element, action or instruction used herein should not be interpreted as critical or essential. In addition, the articles "one" and "an" used herein are intended to include one or more items and can be used interchangeably with "one or more". When only one item is represented, the term "one" or similar language is used. In addition, the terms "have", "have", "include", "include with", etc. used in this article are intended to be open terms. In addition, unless explicitly stated otherwise, the phrase "based on" is intended to mean "based at least in part". In addition, expressions such as "at least one of [A] and [B]" or "at least one of [A] or [B]" should be understood to include only A, only B, or both A and B.

[0026] Reference in this specification to "one embodiment," "an embodiment," or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment of the inventive solution. Thus, the phrases "in one embodiment," "in an embodiment," and similar language in this specification may (but do not necessarily) all refer to the same embodiment.

[0027] In addition, the features, advantages and characteristics of the present disclosure may be combined in any suitable manner in one or more embodiments. Those skilled in the relevant art will recognize from the description herein that the present disclosure may be implemented without one or more specific features or advantages of a particular embodiment. In other cases, additional features and advantages may be recognized in certain embodiments, which may not be present in all embodiments of the present disclosure.

[0028] Embodiments of the present disclosure are intended to perform network energy saving by shutting down transmission chains. In some embodiments, the gNB may enter one of various energy saving states (e.g., a normal state and an energy saving state in which multiple transmission chains are shut down) at a given time and dynamically indicate the current state and future state to the UE. In some embodiments, the gNB may collect feedback from the UE and classify the UE into one of at least two groups based on the feedback: (1) UEs that can maintain acceptable performance when some transmission chains are shut down, and (2) UEs that cannot maintain acceptable performance when some transmission chains are shut down. The UEs in the second group may be configured with coverage enhancement technology. The gNB may dynamically turn on / off multiple transmission chains. When the gNB is in an energy saving state, the UEs in the second group may suspend certain communication activities.

[0029] Figure 1 1 is a schematic diagram of an example device for performing an embodiment of the present disclosure. Device 100 may correspond to any type of known computer, server, or data processing device. For example, device 100 may include a processor, a personal computer (PC), a printed circuit board (PCB) including a computing device, a microcomputer, a mainframe computer, a microcomputer, a telephone computing device, a wired / wireless computing device (e.g., a smartphone, a personal digital assistant (PDA)), a laptop, a tablet computer, a smart device, or any other device with similar functions.

[0030] In some embodiments, Figure 1 As shown, device 100 may include a set of components, such as a processor 120 , a memory 130 , a storage component 140 , an input component 150 , an output component 160 , and a communication interface 170 .

[0031] The bus 110 may include one or more components that allow communication between the components of the device 100. For example, the bus 110 may be a communication bus, a crossbar, a network, etc. Although the bus 110 is not limited to a single bus, it may be a plurality of bus components. Figure 1 Although depicted as a single line in FIG. 1 , bus 110 may be implemented using multiple (two or more) connections between the set of components of device 100. The present disclosure is not limited in this regard.

[0032] Device 100 may include one or more processors, such as processor 120. Processor 120 may be implemented in hardware, firmware, and / or a combination of hardware and software. For example, processor 120 may include a central processing unit (CPU), a graphics processing unit (GPU), an accelerated processing unit (APU), a microprocessor, a microcontroller, a digital signal processor (DSP), a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a general purpose single-chip or multi-chip processor, or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination designed to perform the functions described herein. A general purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. Processor 120 may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors and a DSP core, or any other such configuration. In some embodiments, specific processes and methods may be performed by circuit systems specific to a given function.

[0033] Processor 120 may control the overall operation of device 100 and / or a set of components of device 100 (eg, memory 130 , storage component 140 , input component 150 , output component 160 , communication interface 170 ).

[0034] Device 100 may also include memory 130. In some embodiments, memory 130 may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), flash memory, magnetic memory, optical memory, and / or another type of dynamic or static storage device. Memory 130 may store information and / or instructions used (e.g., executed) by processor 120.

[0035] The storage component 140 of the device 100 may store information and / or computer-readable instructions and / or code related to the operation and use of the device 100. For example, the storage component 140 may include a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optical disk, and / or a solid-state disk), a compact disk (CD), a digital versatile disk (DVD), a universal serial bus (USB) flash drive, a Personal Computer Memory Card International Association (PCMCIA) card, a floppy disk, a cassette, a magnetic tape, and / or another type of non-transitory computer-readable medium, and a corresponding drive.

[0036] Device 100 may also include input component 150. Input component 150 may include one or more components that allow device 100 to receive information, such as through user input (e.g., a touch screen, keyboard, keypad, mouse, stylus, buttons, switches, microphone, camera, etc.). Alternatively, or in addition, input component 150 may include a sensor for sensing information (e.g., a global positioning system (GPS) component, an accelerometer, a gyroscope, an actuator, etc.).

[0037] Output components 160 of device 100 may include one or more components that can provide output information from device 100 (e.g., a display, a liquid crystal display (LCD), a light emitting diode (LED), an organic light emitting diode (OLED), a tactile feedback device, a speaker, etc.).

[0038] The device 100 may also include a communication interface 170. The communication interface 170 may include a receiver component, a transmitter component, and / or a transceiver component. The communication interface 170 may enable the device 100 to establish a connection and / or transmit communication with other devices (e.g., a server, another device). Communication may be achieved by a wired connection, a wireless connection, or a combination of a wired and wireless connection. The communication interface 170 may allow the device 100 to receive information from another device and / or provide information to another device. In some embodiments, the communication interface 170 may communicate with another device via a network, such as a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), a private network, a self-organizing network, an intranet, the Internet, a fiber-based network, a cellular network (e.g., a fifth generation (5G) network, a long-term evolution (LTE) network, a third generation (3G) network, a code division multiple access (CDMA) network, etc.), a public land mobile network (PLMN), a telephone network (e.g., a public switched telephone network (PSTN)), etc., and / or a combination of these or other types of networks. Alternatively or additionally, the communication interface 170 may provide communication with another device via a device-to-device (D2D) communication link such as FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi, LTE, 5G, etc. In other embodiments, the communication interface 170 may include an Ethernet interface, a fiber optic interface, a coaxial interface, an infrared interface, a radio frequency (RF) interface, etc.

[0039] Device 100 may perform one or more processes described herein. Device 100 may perform operations based on processor 120 executing computer-readable instructions and / or code, which may be stored by a non-transitory computer-readable medium (such as memory 130 and / or storage component 140). Computer-readable media may refer to non-transitory memory devices. Memory devices may include storage space within a single physical storage device and / or storage space distributed across multiple physical storage devices.

[0040] Computer-readable instructions and / or code may be read into memory 130 and / or storage component 140 from another computer-readable medium or from another device through communication interface 170. The computer-readable instructions and / or code stored in memory 130 and / or storage component 140, if or when executed by processor 120, may cause device 100 to perform one or more processes described herein.

[0041] Alternatively or additionally, hardwired circuitry may be used in place of or in combination with software instructions to perform one or more of the processes described herein.Thus, the embodiments described herein are not limited to any specific combination of hardware circuitry and software.

[0042] Figure 1The number and arrangement of components shown in the figure are provided as examples only. In practice, there may be more than Figure 1 The components shown in the figure may be more components, fewer components, different components, or components arranged differently. In addition, Figure 1 Two or more of the components shown in may be implemented in a single component, or Figure 1 The single component shown in can be implemented as multiple distributed components. Additionally or alternatively, Figure 1 A set (one or more) of components shown in can be executed by Figure 1 One or more functions performed by another set of components shown in FIG.

[0043] Figure 2 2 is a diagram showing an example of a wireless communication system according to various embodiments of the present disclosure. The wireless communication system 200 (which may also be referred to as a wireless wide area network (WWAN)) may include one or more user equipments (UEs) 210, one or more base stations 220, at least one transport network 230, and at least one core network 240. Device 100 ( Figure 1 ) can be incorporated into UE 210 or base station 220.

[0044] One or more UEs 210 may access at least one core network 240 and / or IP services 250 via a connection to one or more base stations 220 through a RAN domain 224 and at least one transport network 230. Examples of UE 210 may include a cellular phone, a smart phone, a Session Initiation Protocol (SIP) phone, a laptop, a personal digital assistant (PDA), a satellite radio, a global positioning system (GPS), a multimedia device, a video device, a digital audio player (e.g., an MP3 player), a camera, a game console, a tablet, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor / actuator, a display, or any other similarly functional device. Some of the one or more UEs 210 may be referred to as Internet of Things (IoT) devices (e.g., a parking meter, a gas pump, a toaster, a vehicle, a heart monitor, etc.). One or more UEs 210 may also be referred to as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile agent, a client, or some other suitable terminology.

[0045] The one or more base stations 220 may communicate wirelessly with the one or more UEs 210 via the RAN domain 224. Each of the one or more base stations 220 may provide communication coverage for one or more UEs 210 located within the geographic coverage area of ​​the base station 220. Figure 2 As shown, the base station 220 may transmit one or more beamformed signals in one or more transmission directions to one or more UEs 210. The one or more UEs 210 may receive the beamformed signals from the base station 220 in one or more reception directions. Alternatively or additionally, the one or more UEs 210 may transmit the beamformed signals in one or more transmission directions to the base station 220. The base station 220 may receive the beamformed signals from the one or more UEs 210 in one or more reception directions.

[0046] One or more base stations 220 may include macro cells (e.g., high-power cellular base stations) and / or small cells (e.g., low-power cellular base stations). Small cells may include femto cells, pico cells, and micro cells. Base stations 220 (whether macro cells or macro cells) may include and / or be referred to as access points (APs), evolved (or evolved universal terrestrial radio access network (E-UTRAN)) Node Bs (eNBs), next generation Node Bs (gNBs), or any other type of base station known to those skilled in the art.

[0047] The one or more base stations 220 may be configured to interface (e.g., establish a connection, transmit data, etc.) with at least one core network 240 via at least one transport network 230. Among other functions, the one or more base stations 220 may perform one or more of the following functions: transmit data (e.g., uplink data) received from one or more UEs 210 to at least one core network 240 via at least one transport network 230, and transmit data (e.g., downlink data) received from at least one core network 240 to one or more UEs 210 via at least one transport network 230.

[0048] The transport network 230 may transmit data (e.g., uplink data, downlink data) and / or signaling between the RAN domain 224 and the CN domain 244. For example, the transport network 230 may provide one or more backhaul links between one or more base stations 220 and at least one core network 240. The backhaul link may be wired or wireless.

[0049] The core network 240 may be configured to provide one or more services (e.g., enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), and massive machine type communications (mMTC), etc.) to one or more UEs 210 connected to the RAN domain 224 via the TN domain 234. Alternatively or additionally, the core network 240 may serve as an entry point for IP services 250. The IP services 250 may include the Internet, an intranet, an IP multimedia subsystem (IMS), streaming services (e.g., video, audio, games, etc.), and / or other IP services.

[0050] In some embodiments, the gNB (e.g., 220) may deactivate (e.g., turn off, not use) a subset of the transceiver chains, e.g., to save energy. Depending on the mapping of ports to TXRUs, this deactivation may result in one or more ports (e.g., CSI-RS ports) being deactivated. The deactivated resources may not be available to the UE. The state when the TXRU is turned off may be referred to as a power saving state. The state when the TXRU is not turned off may be referred to as a normal state.

[0051] The TXRU may not be visible to the UE (e.g., the UE may not know the exact number of TXRUs used by the gNB). However, deactivating multiple TXRUs may cause multiple ports to be unavailable to the UE. In some embodiments, the gNB may configure at least two separate configurations for the UE. The first configuration may include a first group of ports (e.g., CSI-RS ports) and the second configuration may include a second group of ports. The second group may include a smaller number of antenna ports than the first group. The second configuration may be used when the TXRU chain is deactivated. For example, when there is a one-to-one mapping between CSI-RS ports and TXRUs, with K (e.g., K=32) TXRUs, K CSI-RS ports can be supported. For example, if K / 2 TXRUs are deactivated, K / 2 CSI-RS ports can be supported. In another example, when the TXRU is deactivated, the number of supported ports may not change, but the total transmit power and / or beamwidth may still be reduced to a lower number of active TXRUs. The received signal energy may also be reduced.

[0052] The embodiments of the present disclosure are disclosed assuming that the gNB and / or the network may be in two states (a normal state and a power-saving state). However, the embodiments may be extended to more than two states. For example, there may be multiple power-saving states depending on how much energy each state can save. For example, for K TXRUs, two separate power-saving states may correspond to situations where K / 4 and K / 2 TXRUs are turned off. Although the power-saving state may be achieved by turning off multiple TXRUs, the same embodiments may apply if the power-saving state is enabled by other mechanisms (e.g., turning off antenna elements, etc.).

[0053] In some embodiments, the energy saving process may include detecting UE, UE classification, UE configuration, energy saving state indication, and energy saving application. When detecting the UE, the gNB may instruct the UE to feedback the channel state information (CSI) obtained for normal and / or energy saving state. The UE may also be instructed to report quantities other than CSI. The condition in which the gNB is in when detecting the UE may be referred to as the detection phase. In UE classification, based on UE feedback, UEs may be classified into separate groups. For example, based on their communication capabilities with a reduced number of TXRUs. As an example, UEs that may require enhancement (e.g., coverage enhancement) when multiple TXRUs are turned off may be classified into a first group. UEs that can continue to operate without enhancement may be classified into a second group.

[0054] In the UE configuration, the gNB may configure coverage enhancement or other enhancement techniques for the UEs in the first group. These techniques may be used when the gNB is in an energy saving state. For example, these UEs may be configured to monitor a physical downlink control channel (PDCCH) only when the gNB is in a normal state and not monitor the PDCCH when the gNB is in an energy saving state. In another example, these UEs may be configured to apply the specified coverage enhancement techniques when the gNB is in an energy saving state. During the energy saving state indication, the gNB may adjust the energy saving state behavior over time. For example, the gNB may be in a normal state (e.g., all TXRUs are turned on) in some time slots, and the gNB may be in an energy saving state (e.g., multiple TXRUs are turned off) in some time slots. The gNB state progression over time may be referred to as an energy saving mode, where the current and / or future state of the gNB may be indicated to the UE based on the energy saving mode. After indicating the energy state, the gNB may apply energy saving (e.g., turn off the TXRU according to the indicated energy saving mode). The condition in which the gNB is applying energy saving may be referred to as an energy saving phase. The detection phase and the energy saving phase may overlap partially or completely in time.

[0055] In some embodiments, the gNB may transmit reference signals and / or other signals (e.g., CSI-RS, synchronization signal blocks (SSBs)) that the UE may use to measure and derive CSI. The UE may derive at least two types of CSI (type 1 and type 2). Type 1 may correspond to a reference signal transmitted by the gNB when the gNB is in a normal state. Type 2 may correspond to a reference signal transmitted by the gNB when the gNB is in a power saving state. For example, the gNB may have 32 TXRUs and 32 CSI-RS ports. The UE may use this configuration to obtain a first type of CSI. In a specific interval, the gNB may shut down 16 TXRUs and use the remaining active TXRUs to transmit reference signals. In this specific interval, the number of CSI-RS ports may be set to 16. This configuration may be used to obtain a second type of CSI.

[0056] In some embodiments, the UE may be configured with two CSI reporting configurations. The parameters in one configuration (e.g., the number of CSI-RS ports, the number of CSI-RS resources, etc.) may correspond to a normal state, while the other configuration parameters may correspond to an energy-saving state. The CSI configuration types may be periodic, aperiodic, and semi-static.

[0057] When the base station is not in a power saving state (e.g., normal state), the UE can be configured to measure and report regular CSI. For example, in the normal state, the base station can transmit 64 antennas. In some embodiments, the UE can be instructed to skip CSI-RS measurements in a specific time window. In this time window, the UE can be instructed to measure CSI-RS and report CSI corresponding to the power saving state. For example, for a given interval / window, the gNB instructs the UE to use 8 antennas instead of 64 antennas. This window can be called a time hopping window. Figure 3 An example time sequence 300 with a time hopping window 302 is shown in FIG. During the time hopping window, the base station may be in a power saving state and the UE does not use the original configuration of 64 antennas. Therefore, the UE skips measuring 64 CSI-RS and reporting the corresponding CSI. Instead, during the time hopping window / interval, the UE may only measure 8 antennas and report the CSI of the 8 antennas. As shown in the time sequence 400 with the time window 402 ( Figure 4 ), the UE may measure another set of CSI-RS associated with the energy saving state and report the associated CSI. CSI reporting may be performed outside the window, while DL transmission may only be performed within the window.

[0058] In some embodiments, the hopping window may be configured by the gNB. The window may be periodic and may be configured with the periodicity of the start (or end) of the window, an offset value of the offset start (or end), and a time length (e.g., in time slots or milliseconds). In another approach, each k-th CSI report configured may be configured to be associated with an energy saving state. The reference signal used to obtain each k-th CSI report may be indicated to the UE. For example, it may be assumed that the last CSI-RS and / or the last SSB before the k-th CSI reporting occasion is transmitted with multiple TXRUs turned off. In another example, a window may be defined for the k-th CSI reporting occasion, and it may be assumed that the reference signal within the window is transmitted with the TXRU turned off.

[0059] In another example, the UE may be configured with a CSI report configuration corresponding to a normal state, and the values ​​of certain parameters in the configuration may be temporarily updated. For example, the number of CSI-RS ports in the normal state may be 32. Figure 3During the time window 302 shown, the number of ports may be temporarily set to 16. Similarly, in order to obtain the kth CSI report, the number of ports may also be set to 16.

[0060] In some embodiments, a non-periodic indication may be used to activate CSI reporting in an energy-saving state, such as Figure 5 , which shows an example time sequence 500. The UE may be configured with a type 2 CSI configuration, which may be activated using the PDCCH. The activated type 2 CSI configuration may be deactivated after the validity period ends. The activation of the type 2 CSI reporting configuration may deactivate the type 1 CSI reporting configuration, which means that the UE may skip (e.g., suspend) the type 1 CSI reporting configuration until the validity period ends.

[0061] In some embodiments, the PDCCH may set / reset the values ​​of certain parameters of the CSI configuration. In this regard, after the validity period ends, the values ​​of these parameters may be set to above the values ​​before the PDCCH indication. For example, the MAC CE may indicate the CSI-RS parameters shown in Table 1 to the UE. The bits and / or code points in the PDCCH may set the number of CSI-RS ports in the configuration to one of the values ​​in the table by indicating a row index. The values ​​of other parameters may be added to the table as columns.

[0062]

[0063]

[0064] Table 1

[0065] The detection phase and the energy saving phase may overlap partially or completely, and the embodiments disclosed above may be used during the energy saving phase.

[0066] During the probing phase (e.g., when multiple TXRUs are turned off), certain UE procedures may be skipped and / or suspended. For example, one or more of the following may apply:

[0067] The UE does not monitor the PDCCH;

[0068] The UE suspends evaluating the radio link quality;

[0069] The UE suspends sending an indication to a higher layer (e.g., MAC layer) that the radio link quality is worse than a threshold;

[0070] The UE suspends sending the Physical Random Access Channel (PRACH);

[0071] The UE suspends sending scheduling requests (SR);

[0072] The UE MAC layer suspends incrementing the beam failure indication (BFI) counter and / or starts the beam failure detection timer;

[0073] Set the parameter beamFailureInstanceMaxCount to a large value, for example, infinity; and

[0074] When the UE evaluates the link quality, the UE may use the threshold (Q out,LR +Q out_offset ) and / or (Q in,LR +Q in_offset ), the offset value may be configured by the gNB and may only apply during the probing phase (e.g., within the probing time window). Similarly, the offset value may be added to the parameter Q in and Q out middle.

[0075] In addition to the CSI, the UE may also feedback one or more additional quantities:

[0076] Power margin (tolerance) for beam failure events. For example, reference signal received power (RSRP)-Q out,LR and / or RSRP-Q in_LR ;

[0077] Power margin (tolerance) for radio link failure events. For example, RSRP-Q out and / or RSRP-Q in ;as well as

[0078] The RSRP / SINR measured during the probing phase is subtracted from the RSRP / SINR measured before the probing phase (eg, the last value of RSRP / SINR before the probing phase).

[0079] In some embodiments, using the collected feedback, UEs may be classified based at least on whether the UEs can continue to operate normally when the gNB is in an energy-saving state. For example, a first group of UEs may be located at the center of a cell and may maintain acceptable performance with a certain number of TXRUs turned off. A second group of UEs may be located on the edge of a cell and may maintain acceptable performance if some enhancements are applied (e.g., coverage enhancement when a certain number of TXRUs are turned off). A third group of UEs may not have acceptable performance when a certain number of TXRUs are turned off, even if the enhancements are applied. Different classifications may apply to different levels of energy-saving states.

[0080] In some embodiments, when the gNB enters the power saving state, the behavior of the UEs may be determined by the group they are in. A group ID may be assigned to the UE. Based on the group ID, the UE may adjust its behavior when the gNB is in the power saving state. For example, the UE may be in group 3 and enter sleep mode when the gNB is in the power saving state. In another example, the gNB may send an entry sleep signal before the gNB enters the power saving state and instruct one or more UEs to enter the sleep state. The entry sleep signal may be monitored by UEs belonging to a specific group and / or configured with a specific tag / parameter. The entry sleep signal may be based on the PDCCH, where a bit in the PDCCH may indicate whether a group of UEs enter the sleep state.

[0081] In some embodiments, when the gNB is in an energy-saving state, the UE may be instructed and / or configured to apply coverage enhancement techniques. For example, one or more PDCCH, physical downlink shared channel (PDSCH), physical uplink shared channel (PUSCH), physical uplink control channel (PUCCH) may be repeated depending on the energy-saving state of the gNB. The activation / deactivation of coverage enhancement techniques may be determined by the energy-saving state of the gNB.

[0082] In some embodiments, the gNB may be in different power saving states depending on the specific time. For example, in some time slots, the gNB may be in a normal state, and in some time slots, the gNB may be in a power saving state. The gNB may send an indication of the power saving state to the UE. For example, the UE common PDCCH may be used for indication. The UE may be configured with a search space to monitor the PDCCH. One or more bits in the downlink control information (DCI) may indicate the power saving state for a fixed amount of time. For example, if the duration is N time slots, the bits [1 1 0 0 1] may indicate that the gNB will be in a power saving state (bit 1) during the first, second, and fifth cycles of the N time slots; and the gNB will be in a normal state (bit 0) during the third and fourth cycles of the N time slots. By allocating more bits to each duration, more than two states can be indicated. In another example, the UE may monitor the PDCCH based on the search space. The DCI in the PDCCH may indicate the power saving state and the corresponding duration.

[0083] Embodiments for indicating a probing phase may be used to indicate a power saving state. For example, the power saving phase may occur periodically, and a window similar to a "probing window" may be defined as the time interval during which the gNB is in the power saving phase. As another example, similar to the DRX ON cycle definition, certain time slots may be indicated as belonging to a normal state (e.g., the TXRU is not shut down in these time slots), and the remaining time slots may be indicated as being in a power saving state. In some embodiments, the power saving state may be activated by non-periodic signaling using PDCCH and / or MAC CE, as disclosed for the probing phase.

[0084] Figure 6 A flow chart of an embodiment of a process 600 for performing network energy saving is shown. The process 600 may be performed by a gNB. The process 600 may begin at operation S602, where the gNB sends one or more sounding messages to one or more UEs. The sounding messages may include reference signals, such as CSI reference signals.

[0085] The process continues to operation S604, where the gNB receives one or more CSI reports in response to the one or more sounding messages. The process continues to operation S606, where each UE is classified into one of a plurality of category groups based on the one or more CSI reports. For example, the category groups may include groups 1 to 3 discussed above. The process continues to operation S608, where, based on the category, the UE is configured. For example, the UE may be configured for type 1 or type 2 reference signals as described above. The process continues to operation S610, where, based on the category, the gNB sends a power saving state indication to the UE. For example, the gNB may send a bit pattern (e.g., 1101) to indicate which timeslot the gNB will be in the power saving state. The process continues to operation S612, where, based on the power saving state indication, the gNB applies a power saving mode by shutting down one or more transmission chains.

[0086] Figure 7 A flow chart of an embodiment of a process 700 for probing a UE is shown. Process 700 may begin at operation S702, where a base station sends one or more probing messages to a UE in a first state. For example, the base station may be in a normal state, where each antenna of the base station is turned on. The first group of one or more probing messages may include a reference signal set (e.g., 64 beams). The process proceeds to operation S704, where the base station receives a first CSI report in response to the one or more first group of probing messages. For example, the first CSI report may provide a first CSI corresponding to a measurement of the reference signal set (e.g., 64 beams).

[0087] The process proceeds to operation S706, where the base station sends a second set of one or more sounding messages to the UE in the second state. As an example, the second state may be an energy-saving state in which the base station turns off one or more antennas. The second set of one or more sounding messages may include a subset of reference signals (e.g., 8 beams). An indication may be provided to the UE, indicating the timing of when the base station enters the energy-saving state. The process proceeds to operation S708, where the base station receives a second CSI report in response to the second set of one or more sounding messages. The second CSI report may include a second CSI based on a measurement of the reference signal subset (e.g., 8 beams). Thus, the second CSI report may provide CSI corresponding to the network energy-saving state.

[0088] The above disclosure provides illustration and description, but is not intended to be exhaustive or to limit the embodiments to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of the embodiments.

[0089] It should be understood that the specific order or hierarchy of the blocks in the process / flowchart disclosed herein is an illustration of an example method. According to design preferences, it should be understood that the specific order or hierarchy of the blocks in the process / flowchart can be rearranged. In addition, some blocks can be combined or omitted. The accompanying method claims present the elements of various blocks in an example order and are not meant to be limited to the specific order or hierarchy presented.

[0090] Some embodiments may involve systems, methods, and / or computer-readable media at any possible level of technical detail integration. In addition, one or more of the above components may be implemented as instructions stored on a computer-readable medium and executable by at least one processor (and / or may include at least one processor). The computer-readable medium may include a computer-readable non-transitory storage medium (or medium) having computer-readable program instructions thereon for causing a processor to perform operations.

[0091] A computer-readable storage medium may be a tangible device that can retain and store instructions for use by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the above. A non-exhaustive list of more specific examples of computer-readable storage media includes the following: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), a memory stick, a floppy disk, a mechanical encoding device (such as a punched card or a raised structure in a groove on which instructions are recorded), and any suitable combination of the above. The computer-readable storage medium used herein should not be interpreted as a transient signal itself, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagated through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0092] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to a corresponding computing / processing device, or downloaded to an external computer or external storage device via a network (e.g., the Internet, a local area network, a wide area network, and / or a wireless network). The network can include copper transmission cables, optical transmission fibers, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions to be stored in a computer-readable storage medium in the corresponding computing / processing device.

[0093] The computer readable program code / instructions for performing operations may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, configuration data for integrated circuit systems, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and procedural programming languages, such as "C" programming language or similar programming languages. The computer readable program instructions may be executed entirely on the user's computer, partially on the user's computer, executed as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, an electronic circuit system (e.g., including a programmable logic circuit system, a field programmable gate array (FPGA), or a programmable logic array (PLA)) may be personalized by utilizing the state information of the computer readable program instructions to execute the computer readable program instructions so as to perform various aspects or operations.

[0094] These computer-readable program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device create a means for implementing the functions / actions specified in the flowchart and / or block diagram box. These computer-readable program instructions may also be stored in a computer-readable storage medium, which may instruct the computer, programmable data processing device, and / or other device to operate in a specific manner, so that the computer-readable storage medium storing the instructions includes an article of manufacture, which includes instructions for implementing various aspects of the functions / actions specified in the flowchart and / or block diagram box.

[0095] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device, so that a series of operating steps are performed on the computer, other programmable apparatus, or other device to produce a computer-implemented process, so that the instructions executed on the computer, other programmable apparatus, or other device implement the functions / actions specified in the flowchart and / or block diagram.

[0096] The flowchart and block diagram in the figure show the possible implementation architecture, function and operation of the system, method and computer-readable medium according to various embodiments.In this regard, each frame in the flowchart or block diagram can represent a part of a module, segment or instruction, which includes one or more executable instructions for implementing a specified logical function.The method, computer system and computer-readable medium may include more frames, fewer frames, different frames or frames of different arrangements compared to the frames shown in the figure.In some alternative implementations, the function indicated in the frame may be different from the order indicated in the figure.For example, two frames displayed continuously can actually be executed simultaneously or substantially simultaneously, or sometimes can be executed in reverse order, depending on the functions involved.It should also be noted that each frame in the block diagram and / or flowchart and the combination of frames in the block diagram and / or flowchart can be implemented by a dedicated hardware system that performs a specified function or action or performs a combination of dedicated hardware and computer instructions.

[0097] Obviously, the systems and / or methods described herein can be implemented in various forms of hardware, firmware, or a combination of hardware and software. The actual dedicated control hardware or software code used to implement these systems and / or methods does not limit the implementation. Therefore, the operation and behavior of the systems and / or methods are described herein without reference to specific software code - it should be understood that software and hardware can be designed according to the description herein to implement the systems and / or methods.

[0098] The above disclosure also includes the following embodiments:

[0099] (1) A method executed by at least one processor of a base station, the method comprising:

[0100] In a first state, sending a first set of one or more sounding messages to a UE, wherein the first set of one or more sounding messages includes a reference signal set;

[0101] receiving, in response to the first set of one or more sounding messages, a first channel state information (CSI) report from the UE, the first CSI report comprising first CSI obtained from a measurement of the reference signal set;

[0102] in a second state, sending a second set of one or more sounding messages to the UE, the second set of one or more sounding messages comprising a subset of the reference signal; and

[0103] In response to the second set of one or more sounding messages, a second CSI report is received, the second CSI report comprising second CSI derived from measurements of the subset of the reference signals.

[0104] (2) The method according to feature (1), wherein the first state is a normal state and the second state is a power saving state.

[0105] (3) The method according to feature (2), wherein in the energy saving state, the base station turns off one or more antennas.

[0106] (4) A method according to any one of features (1) to (3), wherein the first set of one or more detection messages includes an indication of a window having a duration for the UE to measure the subset of the reference signals.

[0107] (5) The method according to feature (4), wherein the base station configures the window at periodic time intervals.

[0108] (6) The method according to feature (4) or (5), wherein the second CSI report is transmitted from the UE to the base station at a timing outside the window.

[0109] (7) The method according to any one of features (2) to (6), further comprising:

[0110] A predetermined downlink signal is transmitted to the UE so that the UE terminates measurement of the reference signal set in the normal energy state and initiates measurement of the subset of the reference signals in the energy saving state.

[0111] (8) The method according to feature (7), wherein the predetermined downlink signal is a physical downlink control channel (PDCCH) signal.

[0112] (9) A method according to features (7) or (8), wherein the measurement of the subset of the reference signals is terminated after a predetermined time interval.

[0113] (10) According to any one of features (1) to (9), the method also includes classifying each of the one or more UEs into one of a plurality of category groups based on the one or more CSI reports.

[0114] (11) A method according to feature (10), wherein the multiple category groups include: (i) a first category group, wherein each UE assigned to the first category group does not utilize cell enhancement coverage when the base station is in the energy saving state; and (ii) a second category group, wherein each UE assigned to the second category group utilizes cell enhancement coverage when the base station is in the energy saving state.

[0115] (12) A method according to feature (11), wherein the cell enhancement coverage includes repetition of one or more downlink signals or repetition of one or more uplink signals.

[0116] (13) A method according to feature (12), wherein the one or more downlink signals include one of a physical downlink control channel (PDCCH) signal and a physical downlink shared channel (PDSCH) signal, and wherein the one or more uplink signals include one of a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH) signal.

[0117] (14) The method according to any one of features (2) to (13), further comprising:

[0118] A power saving state indication is transmitted to the UE, the power saving state indication comprising one or more bits specifying one or more time slots in which the power saving state is applied.

[0119] (15) A device comprising:

[0120] at least one memory configured to store computer program code; and

[0121] at least one processor configured to access the at least one memory and to operate according to the instructions of the computer program code, the computer program code comprising:

[0122] a first transmission code configured to cause at least one of the at least one processor to transmit a first set of one or more sounding messages to a UE in a first state, the first set of one or more sounding messages comprising a reference signal set;

[0123] a first receiving code configured to cause at least one of the at least one processor to receive a first channel state information (CSI) report from the UE in response to the first set of one or more sounding messages, the first CSI report comprising first CSI obtained from measurement of the reference signal set;

[0124] a second transmission code configured to cause at least one of the at least one processor to transmit a second set of one or more sounding messages to the UE in a second state, the second set of one or more sounding messages comprising a subset of the reference signal; and

[0125] In response to the second set of one or more sounding messages, a second CSI report is received, the second CSI report comprising second CSI derived from measurements of the subset of the reference signals.

[0126] (16) The device according to feature (15), wherein the first state is a normal state and the second state is a power saving state.

[0127] (17) An apparatus according to feature (16), wherein in the energy saving state, the base station turns off one or more antennas.

[0128] (18) An apparatus according to any one of features (15) to (17), wherein the first set of one or more detection messages includes an indication of a window having a duration for the UE to measure a subset of the reference signals.

[0129] (19) An apparatus according to special feature (18), wherein the base station configures the window at periodic time intervals.

[0130] (20) A non-transitory computer-readable medium having instructions stored therein, wherein when the instructions are executed by a processor in a base station, the processor performs a method, comprising:

[0131] In a first state, sending a first set of one or more sounding messages to a UE, wherein the first set of one or more sounding messages includes a reference signal set;

[0132] receiving, in response to the first set of one or more sounding messages, a first channel state information (CSI) report from the UE, the first CSI report comprising first CSI obtained from a measurement of the reference signal set;

[0133] in a second state, sending a second set of one or more sounding messages to the UE, the second set of one or more sounding messages comprising a subset of the reference signal; and

[0134] In response to the second set of one or more sounding messages, a second CSI report is received, the second CSI report comprising second CSI derived from measurements of the subset of the reference signals.

Claims

1. A method performed by at least one processor of a base station, the method comprising: In a first state, sending a first set of one or more sounding messages to a UE, wherein the first set of one or more sounding messages includes a reference signal set; receiving, in response to the first set of one or more sounding messages, a first channel state information (CSI) report from the UE, the first CSI report comprising first CSI obtained from a measurement of the reference signal set; in a second state, sending a second set of one or more sounding messages to the UE, the second set of one or more sounding messages comprising a subset of the reference signal; as well as In response to the second set of one or more sounding messages, a second CSI report is received, the second CSI report comprising second CSI derived from measurements of the subset of the reference signals. 2 . The method according to claim 1 , wherein the first state is a normal state and the second state is a power saving state. The method of claim 2 , wherein in the energy saving state, the base station turns off one or more antennas.

4. The method of claim 1 , wherein the first set of the one or more probe messages comprises: An indication of a window having a duration during which the UE measures the subset of the reference signals. The method according to claim 4 , wherein the base station configures the window at periodic time intervals. 6 . The method according to claim 4 , wherein the second CSI report is transmitted from the UE to the base station at a timing outside the window.

7. The method according to claim 2, further comprising: A predetermined downlink signal is transmitted to the UE so that the UE terminates measurement of the reference signal set in the normal energy state and initiates measurement of the subset of the reference signals in the energy saving state.

8. The method according to claim 7, wherein the predetermined downlink signal is a Physical Downlink Control Channel (PDCCH) signal.

9. The method of claim 7, wherein the measuring of the subset of the reference signals is terminated after a predetermined time interval.

10. The method according to claim 1, further comprising: Each of the one or more UEs is classified into one of a plurality of category groups based on the one or more CSI reports.

11. The method of claim 10, wherein the plurality of category groups comprises: (i) a first category group, wherein each UE allocated to the first category group does not utilize cell enhancement coverage when the base station is in the energy-saving state; and (ii) a second category group, wherein each UE allocated to the second category group utilizes cell enhanced coverage when the base station is in the energy saving state.

12. The method according to claim 11, wherein the cell enhanced coverage comprises: A repetition of one or more downlink signals, or a repetition of one or more uplink signals.

13. The method of claim 12, wherein the one or more downlink signals comprise: One of a physical downlink control channel (PDCCH) signal and a physical downlink shared channel (PDSCH) signal, and wherein the one or more uplink signals include: one of a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH) signal.

14. The method according to claim 2, further comprising: A power saving state indication is transmitted to the UE, the power saving state indication comprising: one or more bits specifying one or more time slots in which the power saving state is applied.

15. An apparatus comprising: at least one memory configured to store computer program code; as well as at least one processor configured to access the at least one memory and to operate according to the instructions of the computer program code, the computer program code comprising: a first transmission code configured to cause at least one of the at least one processor to transmit a first set of one or more sounding messages to a UE in a first state, the first set of one or more sounding messages comprising a reference signal set; a first receiving code configured to cause at least one of the at least one processor to receive, in response to the first set of one or more sounding messages, a first channel state information (CSI) report from the UE, the first CSI report comprising first CSI obtained from a measurement of the reference signal set; a second transmission code configured to cause at least one of the at least one processor to transmit a second set of one or more sounding messages to the UE in a second state, the second set of one or more sounding messages comprising a subset of the reference signal; and In response to the second set of one or more sounding messages, a second CSI report is received, the second CSI report comprising second CSI derived from measurements of the subset of the reference signals. The apparatus according to claim 15 , wherein the first state is a normal state, and the second state is a power saving state.

17. The apparatus of claim 16, wherein in the power saving state, the base station turns off one or more antennas.

18. The apparatus of claim 15, wherein the first set of the one or more probe messages comprises: An indication of a window having a duration during which the UE measures the subset of the reference signals. The apparatus according to claim 18 , wherein the base station configures the window at periodic time intervals.

20. A non-transitory computer readable medium having instructions stored therein, which, when executed by a processor in a base station, causes the processor to perform a method comprising: In a first state, sending a first set of one or more sounding messages to a UE, wherein the first set of one or more sounding messages includes a reference signal set; receiving, in response to the first set of one or more sounding messages, a first channel state information (CSI) report from the UE, the first CSI report comprising first CSI obtained from a measurement of the reference signal set; in a second state, sending a second set of one or more sounding messages to the UE, the second set of one or more sounding messages comprising a subset of the reference signal; as well as In response to the second set of one or more sounding messages, a second CSI report is received, the second CSI report comprising second CSI derived from measurements of the subset of the reference signals.

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