Method and apparatus for obtaining downlink and uplink channel state information

Abstract

The present disclosure relates to a pre-fifth generation (5G) or 5G communication system that provides for higher data rates beyond fourth generation (4G) communication systems such as Long Term Evolution (LTE). Methods and apparatuses for a CSI reporting mechanism are provided. An apparatus of a user equipment (UE) includes at least one transceiver and at least one processor operably coupled to the at least one transceiver. The at least one processor is configured to determine channel state information (CSI) based on CSI settings, the CSI settings including at least one CSI reporting setting, at least one resource setting, and measurement settings. The at least one transceiver is configured to send the determined CSI to a base station (BS).

Description

[0001] This application is a divisional application of a patent application with an application date of September 1, 2017, an application number of 201780053745.6, and an invention title of "Methods and Apparatus for Downlink and Uplink Channel State Information Acquisition". Technical Field

[0002] The present disclosure generally relates to methods for enabling uplink MIMO. These methods can be used when a user equipment is equipped with multiple transmit antennas and transmit-receive units. Background Art

[0003] In order to meet the increasing demand for wireless data services since the deployment of the 4th generation (4G) communication systems, efforts have been made to develop improved 5th generation (5G) or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "beyond 4G networks" or "post-LTE systems".

[0004] 5G communication systems are considered to be implemented in higher frequency (mmWave) bands (e.g., 28 GHz or 60 GHz bands) in order to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technologies have been discussed in 5G communication systems.

[0005] In addition, in 5G communication systems, developments are underway based on system network improvements such as advanced small cells, cloud radio access network (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multipoint (CoMP), and receiver-side interference cancellation.

[0006] In 5G systems, hybrid FSK and QAM modulation (FQAM) and sliding window superimposed coding (SWSC) as advanced coding modulation (ACM), as well as filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as advanced access technologies, have been developed.

[0007] Wireless communication has been one of the most successful innovations in modern history. Due to the increasing popularity of smart phones and other mobile data devices such as tablets, "notepad" computers, netbooks, e-book readers, and machine types among consumers and enterprises, the demand for wireless data traffic is increasing rapidly. In order to meet the high growth of mobile data traffic and support new applications and deployments, improvements in wireless interface efficiency and coverage are crucial.

[0008] A mobile device or user equipment can measure the quality of a downlink channel and report the quality to a base station, such that various parameters can be determined whether they should be adjusted during communication with the mobile device. The existing channel quality reporting process in a wireless communication system is not sufficient to accommodate the reporting of channel state information associated with a large two-dimensional array of transmit antennas, or an antenna array geometry that generally accommodates a large number of antenna elements. Summary of the Invention

[0009] Various embodiments of the present disclosure provide methods and apparatuses for CSI reporting.

[0010] In one embodiment, a user equipment (UE) is provided. The UE includes a transceiver configured to receive configuration information for channel state information (CSI) calculation and reporting. The configuration information includes settings including at least one CSI reporting setting, at least one reference signal (RS) setting, and measurement settings. The UE further includes a processor operatively connected to the transceiver. The processor is configured to decode the configuration information according to the settings and calculate the CSI. The transceiver is further configured to transmit the calculated CSI on an uplink (UL) channel.

[0011] In another embodiment, a base station (BS) is provided. The BS includes a processor configured to generate configuration information for CSI calculation and reporting. The configuration information includes at least one CSI reporting setting, at least one RS setting, and measurement settings. The BS further includes a transceiver operatively connected to the processor. The transceiver is configured to send the configuration information to the UE via a DL channel and receive a CSI report calculated by the UE in accordance with the configuration information.

[0012] In another embodiment, a method for operating a UE is provided. The method includes the UE receiving configuration information for CSI calculation and reporting. The configuration information includes settings including at least one CSI reporting setting, at least one RS setting, and measurement settings. The method further includes the UE decoding the configuration information, the UE calculating the CSI according to the settings, and the UE transmitting the calculated CSI on an uplink (UL) channel.

[0013] According to various embodiments, an apparatus of a user equipment (UE) includes at least one transceiver and at least one processor operatively coupled to the at least one transceiver. The at least one processor is configured to determine channel state information (CSI) based on CSI settings including at least one CSI reporting setting, at least one resource setting, and measurement settings. The at least one transceiver is configured to send the determined CSI to a base station (BS).

[0014] According to various embodiments, a method for operating a UE includes determining CSI based on CSI settings including at least one CSI reporting setting, at least one resource setting, and measurement settings, and transmitting the determined CSI to a BS.

[0015] According to various embodiments, an apparatus of a BS includes at least one transceiver and at least one processor operatively coupled to the at least one transceiver. The at least one processor is configured to configure a UE to report CSI based on CSI settings including at least one CSI reporting setting, at least one resource setting, and measurement settings. The at least one transceiver is configured to receive the determined CSI from the UE.

[0016] According to various embodiments, a method for operating a BS includes configuring a UE to report CSI based on CSI settings including at least one CSI reporting setting, at least one resource setting, and measurement settings, and receiving the determined CSI from the UE.

[0017] This disclosure relates to providing a pre-fifth-generation (5G) or 5G communication system for supporting higher data rates beyond fourth-generation (4G) communication systems such as Long-Term Evolution (LTE).

[0018] Those skilled in the art can readily appreciate other technical features from the following drawings, description, and claims.

[0019] Before proceeding with the following detailed description, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term "coupled" and its derivatives refer to any direct or indirect communication between two or more elements, whether or not those elements are in physical contact with each other. The terms "transmit," "receive," and "communicate" and their derivatives include both direct and indirect communication. The terms "include" and "comprise" and their derivatives mean including but not limited to. The term "or" is inclusive and means and / or. The phrase "associated with" and its derivatives mean including, included within, interconnected with, containing, contained within, connected to or with, coupled to or with, communicating with, cooperating with, interlacing, juxtaposing, proximate to, bound to, having ownership of, having a relationship with, etc. The term "controller" represents any device, system, or part thereof that controls at least one operation. Such a controller can be implemented in hardware or in a combination of hardware and software and / or firmware. The functions associated with any particular controller can be centralized or distributed, whether locally or remotely. When used with a list of items, the phrase "at least one" means that different combinations of one or more of the listed items can be used and only one item in the list may be required. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C.

[0020] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed from computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, related data, or portions thereof adapted for implementation in a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as read-only memory (ROM), random access memory (RAM), hard disk drive, compact disc (CD), digital video disc (DVD), or any other type of memory. A "non-transitory" computer-readable medium does not include a wired, wireless, optical, or other communication link that transmits transient electrical or other signals. Non-transitory computer-readable media include media that can permanently store data and media that can store and later rewrite data, such as rewritable compact discs or erasable memory devices.

[0021] Definitions for certain other words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that, in many if not most instances, such definitions apply to the prior and future use of such defined words and phrases. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] To more fully understand the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

[0023] Figure 1 An exemplary wireless network is shown in accordance with various embodiments of the present disclosure;

[0024] Figure 2A and Figure 2B An example wireless transmit and receive path is shown in accordance with various embodiments of the present disclosure;

[0025] Figure 3A An example user equipment is shown in accordance with various embodiments of the present disclosure;

[0026] Figure 3B An example base station (BS) is shown in accordance with various embodiments of the present disclosure;

[0027] Figure 4 An example beamforming architecture is shown in which one CSI-RS port is mapped to a large number of analog controlled antenna elements;

[0028] Figure 5AShows an example embodiment of the DL with four CSI report settings and four reference signal settings according to an embodiment of the present disclosure;

[0029] Figure 5B Shows an example embodiment of the DL with four CSI report settings, three reference signal settings and one interference measurement setting according to an embodiment of the present disclosure;

[0030] Figure 5C Shows an example embodiment of the UL with two DL signaling settings, two reference signal settings and one interference measurement setting according to an embodiment of the present disclosure;

[0031] Figure 6 Shows an example CSI report setting according to an embodiment of the present disclosure;

[0032] Figure 7 Shows an example embodiment of the UL with two DL signaling settings and three reference signal settings according to an embodiment of the present disclosure;

[0033] Figure 8 Shows an example DL signaling setting according to an embodiment of the present disclosure;

[0034] Figure 9A Shows a continuous time-domain RS multiplexing scheme according to an embodiment of the present disclosure;

[0035] Figure 9B Shows a discontinuous time-domain RS multiplexing scheme according to an embodiment of the present disclosure;

[0036] Figure 9C Shows a frequency-domain RS multiplexing scheme according to an embodiment of the present disclosure;

[0037] Figure 10 Shows an example relationship between three groups for CSI report configuration according to an embodiment of the present disclosure;

[0038] Figure 11 Shows an example embodiment of the DL with two DL signaling settings and two reference signal settings according to an embodiment of the present disclosure;

[0039] Figure 12 Shows the process of configurable CSI reporting according to an embodiment of the present disclosure;

[0040] Figure 13 Shows a flowchart of an example method in which a UE receives configuration information for channel state information (CSI) calculation and reporting according to an embodiment of the present disclosure; and

[0041] Figure 14A flowchart showing an example method in which a BS generates configuration information (labeled as UE-k) for channel state information (CSI) calculation and reporting for a UE, according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0042] The following discussion Figures 1 to 14 and the various embodiments for describing the principles of the present disclosure in this patent document are merely exemplary and should not be construed in any way as limiting the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any appropriately arranged wireless communication system.

[0043] List of Abbreviations

[0044] · 2D: Two-dimensional

[0045] · MIMO: Multiple-Input Multiple-Output

[0046] · SU-MIMO: Single-User MIMO

[0047] · MU-MIMO: Multi-User MIMO

[0048] · 3GPP: Third Generation Partnership Project

[0049] · LTE: Long Term Evolution

[0050] · UE: User Equipment

[0051] · eNB: Evolved Node B or "eNB"

[0052] · BS: Base Station

[0053] · DL: Downlink

[0054] · UL: Uplink

[0055] · CRS: Cell-Specific Reference Signal

[0056] · DMRS: Demodulation Reference Signal

[0057] · SRS: Sounding Reference Signal

[0058] · UE-RS: UE-Specific Reference Signal

[0059] · CSI-RS: Channel State Information Reference Signal

[0060] · SCID: Scrambling Identity

[0061] · MCS: Modulation and Coding Scheme

[0062] · RE: Resource Element

[0063] ·CQI: Channel Quality Information

[0064] ·PMI: Precoding Matrix Indicator

[0065] ·RI: Rank Indicator

[0066] ·MU-CQI: Multi-User CQI

[0067] ·CSI: Channel State Information

[0068] ·CSI-IM: CSI Interference Measurement

[0069] ·CoMP: Coordinated Multi-Point

[0070] ·DCI: Downlink Control Information

[0071] ·UCI: Uplink Control Information

[0072] ·PDSCH: Physical Downlink Shared Channel

[0073] ·PDCCH: Physical Downlink Control Channel

[0074] ·PUSCH: Physical Uplink Shared Channel

[0075] ·PUCCH: Physical Uplink Control Channel

[0076] ·PRB: Physical Resource Block

[0077] ·RRC: Radio Resource Control

[0078] ·AoA: Angle of Arrival

[0079] ·AoD: Angle of Departure

[0080] The following documents and standards are incorporated herein by reference as if fully set forth herein: 3GPP Technical Specification (TS) 36.211 version 12.4.0, "E-UTRA, Physical Channels and Modulation" ("REF 1"); 3GPP TS 36.212 version 12.3.0, "E-UTRA, Multiplexing and Channel Coding" ("REF 2"); 3GPP TS 36.213 version 12.4.0, "E-UTRA, Physical Layer Procedures" ("REF 3"); 3GPP TS 36.321 version 12.4.0, "E-UTRA, Medium Access Control (MAC) Protocol Specification" ("REF 4"); and 3GPP TS 36.331 version 12.4.0, "E-UTRA, Radio Resource Control (RRC) Protocol Specification" ("REF 5").

[0081] Figure 1FIG. 0 illustrates an exemplary wireless network 100 in accordance with various embodiments of the present disclosure. Figure 1 The embodiments of the wireless network 100 shown in FIG. 0 are for illustration only. Other embodiments of the wireless network 100 may be used without departing from the scope of the present disclosure.

[0082] The wireless network 100 includes base stations (BSs) 101, 102, and 103. BS 101 communicates with BSs 102 and 103. BS 101 also communicates with at least one Internet Protocol (IP) network 130, such as the Internet, a proprietary IP network, or other data networks. Alternative terms such as “eNB” (evolved Node B) or “gNB” (gNode B) may be used instead of “BS”. Depending on the network type, other well-known terms may be used instead of “gNB” or “BS”, such as “base station” or “access point”. For convenience, the terms “gNB” and “BS” are used in this patent document to refer to network infrastructure components that provide wireless access to remote terminals. Additionally, depending on the network type, other well-known terms may be used instead of “user equipment” or “UE”, such as “mobile station”, “user station”, “remote terminal”, “wireless terminal”, or “user device”. For convenience, the terms “user equipment” and “UE” are used in this patent document to refer to remote wireless devices that wirelessly access the gNB, regardless of whether the UE is a mobile device (e.g., a mobile phone or smartphone) or is generally considered a fixed device (e.g., a desktop computer or a vending machine).

[0083] gNB 102 provides wireless broadband access to the network 130 for a first plurality of user equipment (UEs) within the coverage area 120 of gNB 102. The first plurality of UEs includes UE 111, which may be located in a small business (SB); UE 112, which may be located in an enterprise (E); UE 113, which may be located in a WiFi hotspot (HS); UE 114, which may be located in a first residence (R); UE 115, which may be located in a second residence (R); UE 116, which may be a mobile device (M) such as a mobile phone, a wireless laptop, a wireless PDA, etc. gNB 103 provides wireless broadband access to the network 130 for a second plurality of UEs within the coverage area 125 of gNB 103. The second plurality of UEs includes UE 115 and UE 116. In some embodiments, one or more of the UEs include UE 115 and UE 116. gNBs 101 - 103 may communicate with each other and with UEs 111 - 116 using 5G, LTE, LTE-A, WiMAX, or other advanced wireless communication technologies.

[0084] The dashed lines illustrate the approximate extents of coverage areas 120 and 125, which are shown as approximately circular for purposes of illustration and explanation only. It should be clearly understood that coverage areas associated with gNBs, such as coverage areas 120 and 125, may have other shapes, including irregular shapes, depending on the configuration of the gNB and variations in the RF environment associated with natural and human-created obstacles.

[0085] As described in more detail below, one or more of gNB 101, gNB 102, and gNB 103 send measurement reference signals to UEs 111-116, and configure UEs 111-116 for CSI reporting as described in embodiments of the present disclosure. In various embodiments, one or more of UEs 111-116 receive CSI acquisition configuration information and send CSI reports accordingly.

[0086] although Figure 1 One example of a wireless network 100 is shown, but may be Figure 1 Various changes may be made. For example, wireless network 100 may include any number of gNBs and any number of UEs in any suitable arrangement. In addition, gNB 101 may communicate directly with any number of UEs and provide those UEs with wireless broadband access to network 130. Similarly, each gNB 102-103 may communicate directly with network 130 and provide UEs with direct wireless broadband access to network 130. In addition, gNBs 101, 102, and / or 103 may provide access to other or additional external networks, such as an external telephone network or other type of data network.

[0087] Figure 2A and Figure 2B Exemplary wireless transmit and receive paths according to the present disclosure are shown. In the following description, transmit path 200 may be described as being implemented in a gNB (such as gNB 102) and receive path 250 may be described as being implemented in a UE (such as UE 116). However, it should be understood that receive path 250 may be implemented in a gNB and transmit path 200 may be implemented in a UE. In some embodiments, receive path 250 is configured to acquire CSI configuration information and send CSI reports accordingly, as described in embodiments of the present disclosure.

[0088] The transmit path 200 includes a channel coding and modulation block 205, a serial-to-parallel (S-to-P) block 210, an inverse fast Fourier transform (IFFT) block 215 of size N, a parallel-to-serial (P-to-S) block 220, a "add cyclic prefix" block 225, and an upconverter (UC) 230. The receive path 250 includes a downconverter (DC) 255, a "remove cyclic prefix" block 260, a serial-to-parallel (S-to-P) block 265, a fast Fourier transform (FFT) block 270 of size N, a parallel-to-serial (P-to-S) block 275, and a channel decoding and demodulation block 280.

[0089] In the transmit path 200, the channel coding and modulation block 205 receives a set of information bits, applies coding (e.g., convolutional, Turbo, or low-density parity-check (LDPC) coding), and modulates the input bits (e.g., using quadrature phase shift keying (QPSK) or quadrature amplitude modulation (QAM)) to generate a sequence of frequency-domain modulation symbols. The S-to-P block 210 converts the serial modulation symbols (e.g., demultiplexes) into parallel data to generate N parallel symbol streams, where N is the IFFT / FFT size used in gNB 102 and UE 116. The IFFT block 215 of size N performs an IFFT operation on the N parallel symbol streams to generate a time-domain output signal. The P-to-S block 220 converts (e.g., multiplexes) the parallel time-domain output symbols from the IFFT block 215 of size N to generate a serial time-domain signal. The "add cyclic prefix" block 225 inserts a cyclic prefix into the time-domain signal. The UC 230 modulates (e.g., upconverts) the output of the "add cyclic prefix" block 225 to an RF frequency for transmission via the wireless channel. Before transforming to the RF frequency, the signal may also be filtered at baseband.

[0090] The RF signal transmitted from gNB 102 arrives at UE 116 after passing through the wireless channel, and the operations opposite to those at gNB 102 are performed at UE 116. The DC 255 downconverts the received signal to baseband frequency, and the "remove cyclic prefix" block 260 removes the cyclic prefix to generate a serial time-domain baseband signal. The serial-to-parallel block 265 converts the time-domain baseband signal into a parallel time-domain signal. The FFT block 270 of size N performs the FFT algorithm to generate N parallel frequency-domain signals. The parallel-to-serial block 275 converts the parallel frequency-domain signals into a sequence of modulation data symbols. The channel decoding and demodulation block 280 demodulates and decodes the modulation symbols to recover the original input data stream.

[0091] As described in more detail below, the transmit path 200 or the receive path 250 may perform signaling for CSI reporting. Each of the gNBs 101 - 103 may implement a transmit path 200 similar to that transmitted to the UEs 111 - 116 in the downlink, and may implement a receive path 250 similar to that received from the UEs 111 - 116 in the uplink. Similarly, each of the UEs 111 - 116 may implement a transmit path 200 for transmitting to the gNBs 101 - 103 in the uplink, and may implement a receive path 250 for receiving from the gNBs 101 - 103 in the downlink.

[0092] may be implemented using only hardware or using a combination of hardware and software / firmware Figure 2A and Figure 2B each component in. As a specific example, Figure 2A and Figure 2B at least some of the components in may be implemented in software, while other components may be implemented by configurable hardware or a mixture of software and configurable hardware. For example, the FFT block 270 and the IFFT block 215 may be implemented as configurable software algorithms, where the value of the size N may be modified according to the implementation.

[0093] Furthermore, although described as using FFT and IFFT, this is merely exemplary and should not be construed as limiting the scope of the present disclosure. Other types of transforms may be used, such as the discrete Fourier transform (DFT) and the inverse discrete Fourier transform (IDFT) functions. It should be understood that the value of the variable N may be any integer for the DFT and IDFT functions (e.g., 1, 2, 3, 4, etc.), while the value of the variable N may be any integer that is a power of 2 for the FFT and IFFT functions (e.g., 1, 2, 4, 8, 16, etc.).

[0094] Although Figure 2A and Figure 2B show examples of wireless transmit and receive paths, various changes may be made to Figure 2A and Figure 2B . For example, Figure 2A and Figure 2B the various components in may be combined, further subdivided, or omitted, and additional components may be added according to specific requirements. Moreover, Figure 2A and Figure 2B are intended to show examples of the types of transmit and receive paths that may be used in a wireless network. Other suitable architectures may be used to support wireless communication in a wireless network.

[0095] Figure 3A shows an example UE 116 according to the present disclosure. Figure 3A The embodiment of the UE 116 shown in is for illustration only, and Figure 1The UEs 111-115 can have the same or similar configurations. However, UEs have a wide variety of configurations, and Figure 3A does not limit the scope of the present disclosure to any particular implementation of the UE.

[0096] UE 116 includes an antenna 305, a radio frequency (RF) transceiver 310, a transmit (TX) processing circuit 315, a microphone 320, and a receive (RX) processing circuit 325. UE 116 also includes a speaker 330, a processor 340, an input / output (I / O) interface 345, an input 350, a display 355, and a memory 360. The memory 360 includes an operating system (OS) program 361 and one or more applications 362.

[0097] The RF transceiver 310 receives an input RF signal transmitted by the gNB of the Figure 1 wireless network 100 from the antenna 305. The RF transceiver 310 down-converts the input RF signal to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is sent to the RX processing circuit 325 that generates a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. The RX processing circuit 325 sends the processed baseband signal to the speaker 330 (e.g., for voice data) or to the processor 340 for further processing (e.g., for web browsing data).

[0098] The TX processing circuit 315 receives analog or digital voice data from the microphone 320 or other output baseband data (such as network data, email, or interactive video game data) from the processor 340. The TX processing circuit 315 encodes, multiplexes, and / or digitizes the output baseband data to generate a processed baseband or IF signal. The RF transceiver 310 receives the output processed baseband or IF signal from the TX processing circuit 315 and up-converts the baseband or IF signal to an RF signal transmitted via the antenna 305.

[0099] The processor 340 can include one or more processors or other processing devices and runs the OS program 361 stored in the memory 360 to control the overall operation of the UE 116. For example, the processor 340 can control the reception of forward channel signals and the transmission of reverse channel signals by the RF transceiver 310, the RX processing circuit 325, and the TX processing circuit 315 according to well-known principles. In some embodiments, the processor 340 includes at least one microprocessor or microcontroller.

[0100] The processor 340 is also capable of running other processes and programs resident in the memory 360, such as operations for CQI measurement and reporting of the systems described in embodiments of the present disclosure. The processor 340 can move data into or out of the memory 360 as needed for running processes. In some embodiments, the processor 340 is configured to run the application 362 based on the OS program 361 or in response to signals received from the gNB or the operator. The processor 340 is also coupled to an I / O interface 345 that provides the UE 116 with the ability to connect to other devices such as laptop computers and handheld computers. The I / O interface 345 is a communication path between these accessories and the processor 340.

[0101] The processor 340 is also coupled to an input 350 (e.g., keypad, touch screen, buttons, etc.) and a display 355. The operator of the UE 116 can use the input 350 to input data into the UE 116. The display 355 can be a liquid crystal display or other display capable of presenting text and / or at least limited graphics (e.g., from a website).

[0102] The memory 360 is coupled to the processor 340. A portion of the memory 360 can include random access memory (RAM), and another portion of the memory 360 can include flash memory or other read-only memory (ROM).

[0103] As described in more detail below, the UE 116 can perform signaling and calculations for CSI reporting. Although Figure 3A one example of the UE 116 is shown, various changes can be made. For example, depending on specific needs, Figure 3A the various components in Figure 3A can be combined, further subdivided, or omitted, and additional components can be added. As a specific example, the processor 340 can be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). Moreover, although Figure 3A the UE 116 is shown configured as a mobile phone or a smart phone, the UE can be configured to operate as other types of mobile or fixed devices.

[0104] According to various embodiments, a user equipment (UE) includes a transceiver configured to receive configuration information for channel state information (CSI) calculation and reporting, where the configuration information includes settings including at least one CSI reporting setting, at least one reference signal (RS) setting, and measurement settings; and a processor operably connected to the transceiver, the processor being configured to decode the configuration information and calculate CSI according to the settings. The transceiver is also configured to transmit the calculated CSI on an uplink (UL) channel.

[0105] In some embodiments, configuration information is received via higher layer signaling.

[0106] Figure 3B An exemplary gNB 102 according to the present disclosure is shown. Figure 3B The embodiment of the gNB 102 shown is for illustration only, and Figure 1 other gNBs may have the same or similar configurations. However, gNBs have a wide variety of configurations, and Figure 3B the scope of the present disclosure is not limited to any particular implementation of the gNB. gNB 101 and gNB 103 may include structures the same as or similar to those of gNB 102.

[0107] As Figure 3B shown, gNB 102 includes a plurality of antennas 370a - 370n, a plurality of RF transceivers 372a - 372n, transmit (TX) processing circuitry 374, and receive (RX) processing circuitry 376. In certain embodiments, one or more of the plurality of antennas 370a - 370n includes a 2D antenna array. gNB 102 also includes a controller / processor 378, a memory 380, and a backhaul or network interface 382.

[0108] The RF transceivers 372a - 372n receive input RF signals from the antennas 370a - 370n, such as signals transmitted by a UE or other gNBs. The RF transceivers 372a - 372n down-convert the input RF signals to generate IF or baseband signals. The IF or baseband signals are sent to the RX processing circuitry 376 that generates a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. The RX processing circuitry 376 sends the processed baseband signal to the controller / processor 378 for further processing.

[0109] The TX processing circuitry 374 receives analog or digital data (such as voice data, network data, email, or interactive video game data) from the controller / processor 378. The TX processing circuitry 374 encodes, multiplexes, and / or digitizes the output baseband data to generate a processed baseband or IF signal. The RF transceivers 372a - 372n receive the output processed baseband or IF signal from the TX processing circuitry 374 and up-convert the baseband or IF signal to an RF signal transmitted via the antennas 370a - 370n.

[0110] The controller / processor 378 may include one or more processors or other processing devices that control the overall operation of the gNB 102. For example, the controller / processor 378 may control the reception of forward channel signals and the transmission of reverse channel signals by the RF transceivers 372a - 372n, the RX processing circuitry 376, and the TX processing circuitry 374 according to well-known principles. The controller / processor 378 may also support additional functions, such as more advanced wireless communication functions. In some embodiments, the controller / processor 378 includes at least one microprocessor or microcontroller.

[0111] The controller / processor 378 is also capable of executing programs and other processes residing in the memory 380, such as the OS. As described in embodiments of the present disclosure, the controller / processor 378 is also capable of supporting channel quality measurement and reporting for a system with a 2D antenna array. In some embodiments, the controller / processor 378 supports communication between entities such as web RTC. The controller / processor 378 may move data into or out of the memory 380 as needed during the operation process.

[0112] The controller / processor 378 is also coupled to the backhaul or network interface 382. The backhaul or network interface 382 allows the gNB 102 to communicate with other devices or systems via a backhaul connection or via a network. The backhaul or network interface 382 may support communication via any suitable wired or wireless connection. For example, when the gNB 102 is implemented as part of a cellular communication system (such as one that supports 5G or new radio access technology or NR, LTE, or LTE-A), the backhaul or network interface 382 may allow the gNB 102 to communicate with other gNBs via a wired or wireless backhaul connection. When the gNB 102 is implemented as an access point, the backhaul or network interface 382 may allow the gNB 102 to communicate with a larger network (such as the Internet) via a wired or wireless local area network or via a wired or wireless connection. The backhaul or network interface 382 includes any suitable structure that supports communication via a wired or wireless connection, such as Ethernet or an RF transceiver.

[0113] The memory 380 is coupled to the controller / processor 378. A portion of the memory 380 may include RAM, and another portion of the memory 380 may include flash memory or other ROM. In certain embodiments, multiple instructions, such as BIS algorithms, are stored in the memory. The multiple instructions are configured such that the controller / processor 378 performs BIS processing and decodes the received signal after subtracting at least one interference signal determined by the BIS algorithm.

[0114] As described in more detail below, the transmit and receive paths of gNB 102 (implemented using RF transceivers 372a - 372n, TX processing circuitry 374, and / or RX processing circuitry 376) perform configuration and signaling for CSI acquisition.

[0115] Although Figure 3B an example of gNB 102 is shown, various changes may be made to Figure 3B it. For example, gNB 102 may include any number of Figure 3A each of the components shown in. As a specific example, an access point may include multiple backhaul or network interfaces 382, and the controller / processor 378 may support routing functions to route data between different network addresses. As another specific example, although shown as including a single instance of TX processing circuitry 374 and a single instance of RX processing circuitry 376, gNB 102 may include multiple instances of each (such as one for each RF transceiver).

[0116] According to various embodiments, a base station (BS) includes a processor configured to generate configuration information for channel state information (CSI) calculation and reporting, and a transceiver operably connected to the processor. The configuration information includes at least one CSI reporting setting, at least one reference signal (RS) setting, and measurement settings. The transceiver is configured to send the configuration information to a UE via a downlink (DL) channel and receive a CSI report calculated based on the configuration information from the UE.

[0117] In some embodiments, the configuration information is sent / received via higher layer signaling.

[0118] Rel.13 LTE supports up to 16 CSI - RS antenna ports, which enables a gNB to be equipped with a large number of antenna elements (e.g., 64 or 128). In this case, multiple antenna elements are mapped to one CSI - RS port. Additionally, up to 32 CSI - RS ports will be supported in Rel.14 LTE. For next - generation cellular systems such as 5G, the maximum number of CSI - RS ports is expected to remain more or less the same.

[0119] For the mmWave band, although the number of antenna elements may be larger for a given form factor, as Figure 4As shown in Example 400, the number of CSI-RS ports (which may correspond to the number of digital precoding ports) tends to be limited due to hardware limitations (such as the feasibility of installing a large number of ADC / DACs at mmWave frequencies). In this case, one CSI-RS port is mapped to a large number of antenna elements that can be controlled by a set of analog phase shifters 401. Then, one CSI-RS port can correspond to a subarray that generates a narrow analog beam through analog beamforming 405. The analog beam can be configured to scan a wider range of angles 420 by changing the set of phase shifters across symbols or subframes or time slots (where a subframe or time slot includes a set of symbols). The number of subarrays (equal to the number of RF chains) is the same as the number of CSI-RS ports N CSI-PORT The digital beamforming unit 410 performs a linear combination across N CSI-PORT analog beams to further increase the precoding gain. Although the analog beam is broadband (and thus not frequency selective), the digital precoding can vary across frequency subbands or resource blocks.

[0120] To implement digital precoding, an effective design of CSI-RS is a key factor. For this purpose, three types of CSI reporting mechanisms corresponding to three types of CSI-RS measurement behaviors are supported in Rel.13 LTE: 1) "CLASS A" CSI reporting corresponding to non-precoded CSI-RS; 2) "CLASS B" using K=1 CSI-RS resource reporting, which corresponds to UE-specific beamforming CSI-RS; 3) "CLASS B" using K>1 CSI-RS resource reporting, which corresponds to cell-specific beamforming CSI-RS. For non-precoded (NP) CSI-RS, a cell-specific one-to-one mapping between the CSI-RS port and the TXRU is used. Here, different CSI-RS ports have the same wide beam width and direction and thus generally the same cell coverage. For beamformed CSI-RS, cell-specific or UE-specific beamforming operations are applied to non-zero power (NZP) CSI-RS resources (which include multiple ports). Here, (at least at a given time / frequency) the CSI-RS ports have a narrow beam width and thus do not have cell-wide coverage, and (at least from the gNB perspective) at least some of the CSI-RS port resource combinations have different beam directions.

[0121] In the case of measuring DL long-term channel statistics by UL signals at the serving gNB, UE-specific BF CSI-RS can be easily used. This is generally feasible when the UL-DL duplex distance is small enough. However, when this condition does not hold, some UE feedback is used for the gNB to obtain an estimate of the DL long-term channel statistics (or any representation thereof). To facilitate such a process, the first BF CSI-RS is sent periodically at T1 (ms, milliseconds) and the second NP CSI-RS is sent periodically at T2 (ms), where T1 ≤ T2. This method is called hybrid CSI-RS. The implementation of hybrid CSI-RS depends to a large extent on the CSI process and the definition of NZP CSI-RS resources.

[0122] In LTE, there are multiple CSI reporting modes for both periodic (based on PUCCH) and aperiodic (based on PUSCH) CSI reporting. Each CSI reporting mode depends on (is coupled with) many other parameters (e.g., codebook selection, transmission mode, eMIMO type, RS type, number of CRS or CSI-RS ports). At least two drawbacks can be perceived. First, there are complex "nested loops" (IF...ELSE...) and coupling / connection networks. This complicates the testing work. Second, forward compatibility is limited, especially when introducing new features.

[0123] Although the above drawbacks apply to DL CSI measurements, the same can be said for UL CSI measurements. In LTE, the UL CSI measurement framework exists in its original form and has not evolved as much as its DL counterpart. With the emergence of TDD or reciprocity-based systems for next-generation systems and the potential significance of OFDMA or OFDMA-based multiple access for UL, it is beneficial to have the same (or at least similar) CSI measurement and reporting frameworks for both DL and UL.

[0124] Therefore, considering the above new challenges of the 5G NR system, a flexible and modular CSI measurement and reporting framework applicable to both DL and UL is needed.

[0125] This disclosure includes the following components for implementing CSI acquisition for DL and UL. The first component (Component 1) includes a framework for supporting DL CSI acquisition and its associated embodiments. The second component includes a framework and embodiments for supporting UL CSI acquisition. The third component includes another framework for supporting DL CSI acquisition and its related embodiments.

[0126] Component 1 - DL CSI Framework

[0127] For the first component (i.e., the DL CSI acquisition framework), the DL CSI framework is partially designed to facilitate DL CSI acquisition at the gNB / TRP. This involves DL CSI reports from the UE, DL CSI measurements of UL signals at the gNB / TRP (for DL-UL reciprocity-based operations), or both.

[0128] In one example embodiment, for a single UE, the DL CSI framework includes at least one CSI report setting, at least one RS setting (which includes at least one RS for CSI measurement), and a CSI measurement setting. The CSI report setting configures for the UE the CSI report parameters that need to be calculated and reported. The RS setting configures for the UE one or more RS resources for CSI measurement and calculation. For example, one of the configured RSs can be a CSI-RS, which also includes a special case of CSI-IM (thus a zero-power CSI-RS). The CSI measurement setting provides the link / coupling between the CSI report and the RS setting.

[0129] Note that the above specifications (CSI report setting, RS setting, and CSI measurement setting) are exemplary and for illustrative purposes only. Other names can also be used to represent the functions. For example, the RS setting can be referred to as a resource setting or a CSI resource setting, indicating the resource configuration of the signal (e.g., reference signal) for measurement. In other words, hereinafter, the RS setting can refer to the resource setting. Examples of signals that can be used for a reference signal include CSI-RS, DMRS (demodulation reference signal), or SRS (sounding reference signal).

[0130] For example, when the UE is configured with N CSI report settings and M RS settings, the CSI measurement setting links each of the N CSI report settings to at least one of the M RS settings. This is shown in Figure 5A where N = 4 (CSI report settings indexed by 0, 1, 2, and 3, which are associated with embodiments 510, 511, 512, and 513 respectively) and M = 4 (RS settings indexed by 0, 1, 2, and 3, which are associated with embodiments 515, 516, 517, and 518 respectively).

[0131] The CSI measurement settings can be described as follows. Four CSI report settings and four RS settings are linked to the CSI measurement setting 520. In this example, CSI report settings 0 and 1 are linked to RS setting 0. CSI report setting 2 is linked to RS setting 1. On the other hand, CSI report setting 3 is linked to RS settings 2 and 3. As a final example, where one CSI report setting is linked to two RS settings, it applies to hybrid CSI operations (where one RS setting is cell- or TRP-specific or gNB-specific, and the other is UE-specific and beamformed) and CoMP (where one RS setting is associated with one interference hypothesis and the other RS setting is associated with another interference hypothesis). Generally, in the CSI measurement settings, there can be L≥1 links that link N CSI report settings and M RS settings.

[0132] In addition to the above links, the timing relationship between the CSI report and its corresponding RS can be included in the CSI measurement settings. For example, when CSI report setting 0 is associated with RS setting 0, the UE behavior is defined as follows. When the UE receives the RS associated with RS setting 0 in subframe or slot n, the UE will report the CSI associated with CSI report setting 0 in subframe or slot n+D 0-0 where the parameter D 0-0 is configurable. In the example shown in Figure 5A , there are at least five such parameters (D 0-0 , D 1-0 , D 2-1 , D 3-2 and D 3-3 ). Optionally, each link can be associated with a set of possible values, and the value applied to a specific measurement and reporting instance can be dynamically selected from this set of values.

[0133] Furthermore, measurement limitations (not only location but also the extent of measuring CSI in the time domain, frequency domain, or both) associated with each link can be included in the CSI measurement settings.

[0134] In addition, quasi-colocation (QCL) in more than one antenna port can be included in the CSI measurement settings.

[0135] At least one (or a combination of several) of the above example contents of the CSI measurement settings can be selected to form the CSI measurement settings.

[0136] In a variation of the above embodiment, instead of using one CSI measurement setting that utilizes all (L≥1) links between N CSI report settings and M RS settings, L≥1 separate CSI measurement settings (one CSI measurement setting per link) can be used. In this case, one CSI measurement setting can include at least one of the following: link, timing relationship, measurement restriction, and / or QCL. The detailed description of using L≥1 CSI measurement settings follows the settings for one CSI measurement setting.

[0137] The above settings can be configured for the UE via higher layer (RRC) signaling, or MAC control element (MAC CE), or L1 control signaling (DL control signaling via the DL control channel). There are several possibilities. First, all of the above settings (CSI report settings, RS settings, and CSI measurement settings) can be configured via higher layer (RRC) signaling or MAC control element (MAC CE). Second, the CSI report settings and RS settings can be configured via higher layer (RRC) signaling, while the CSI measurement settings can be configured via MAC control element (MAC CE). Third, the CSI report settings and RS settings can be configured via higher layer (RRC) signaling, while the CSI measurement settings can be configured via L1 control signaling (DL control signaling via the DL control channel). Fourth, the CSI report settings and CSI measurement settings can be configured via higher layer (RRC) signaling, while the RS settings can be configured via L1 control signaling (DL control signaling via the DL control channel).

[0138] Optionally, for at least one of the above three settings, some setting parameters can be configured via higher layer (RRC) signaling or MAC CE, while some other setting parameters can be configured via L1 DL control signaling (using UL-related or DL-related DCI). Some examples will be given below.

[0139] The DL transmission scheme / method is configured separately. How the DL transmission scheme / method is used together with CSI-related settings is left to the gNB implementation. Optionally, this DL transmission scheme can be used as a condition for CQI calculation.

[0140] As described below, the time-domain behavior of CSI reporting, DL CSI-RS, and UL SRS transmission includes periodic (P), semi-persistent (SP), and aperiodic (AP). Several possible implementation schemes are given below.

[0141] In an example embodiment, CSI report settings can be dynamically selected for aperiodic and semi-persistent CSI reporting. When a UE is configured with n > 1 CSI report settings each of which configures one of n CSI report settings including aperiodic CSI reporting, the DCI for triggering aperiodic CSI reporting can include a CSI report setting index (which indicates one associated with the n CSI report settings) as part of a separate DCI field or CSI request field. Similarly, when a UE is configured with n' > 1 CSI report settings each of which configures one of n' CSI report settings including semi-persistent CSI reporting, the DCI or MAC CE for activating semi-persistent CSI reporting can include a CSI report setting index (which indicates one associated with the n' CSI report settings) as part of a separate field or activation message. This embodiment also applies when not all configuration links between each CSI report setting and all RS settings can be dynamically selected. That is, when a CSI report setting is dynamically selected, all RS settings linked to the selected CSI report setting are used for CSI measurement.

[0142] In another example embodiment, RS or resource settings can be dynamically selected for aperiodic and semi-persistent CSI reporting. When a UE is configured with m > 1 RS or resource settings each of which configures one of m aperiodic CSI-RS RS settings, the DCI for triggering aperiodic CSI reporting can include an RS setting index (which indicates one associated with the m RS settings) as part of a separate DCI field or CSI request field. Similarly, when a UE is configured with m' > 1 RS settings each of which configures one of m' semi-persistent CSI-RS RS settings, the DCI for triggering aperiodic CSI reporting, or the DCI or MAC CE for activating semi-persistent CSI reporting, can include an RS setting index (which indicates one associated with the m' CSI report settings) as part of a separate field or activation message or (for aperiodic CSI reporting) part of a CSI request field. This embodiment also applies when not all configuration links between each RS setting and all CSI report settings can be dynamically selected. That is, when an RS setting is dynamically selected, all CSI report settings linked to the selected RS setting are active.

[0143] The above embodiments apply to other types of RS such as SRS. It also applies to non-zero power (NZP) or zero power (ZP) CSI-RS or SRS.

[0144] In another example embodiment, CSI report settings and RS / resource settings can be dynamically selected for aperiodic and semi-persistent CSI reporting. In this case, the selected links within the CSI measurement settings (including a total of L links) can be signaled dynamically. When the UE is configured with l>1 links for aperiodic CSI reporting, the DCI for triggering the aperiodic CSI report can include a link index (which indicates the associated one of the l links), either as a separate DCI field or as part of a CSI request field. Similarly, when the UE is configured with l'>1 links for semi-persistent CSI reporting, the DCI or MAC CE for activating the semi-persistent CSI report can include a link index (which indicates the associated one of the l' links), either as a separate DCI field or as part of an activation message. When using link-based dynamic signaling, the UE can measure resources / RS from different RS settings for the same CSI report settings based on the selected / triggered links.

[0145] In the above embodiment for the first component (for DL CSI), the RS for interference measurement (IM or CSI-IM) is included in the RS settings (e.g., in the RS power setting, RS type, and / or RS function). In an alternative embodiment, instead of including the RS for IM in the RS settings, a separate IM (interference measurement) setting can be used. In this case, the UE can be configured with one CSI measurement setting that includes all (L≥1) links among N CSI report settings, M RS settings, and P IM settings. This is shown in Figure 5B where L = 5 links are included in the CSI measurement setting 550, and N = 4 CSI report settings (540, 541, 542, and 543), M = 3 RS settings (545, 546, and 547), and P = 1 IM setting (548). The content of the IM setting can include at least one of the content of the RS settings, as disclosed in the above description of the first component.

[0146] In a variation of the above alternative embodiment, instead of using one CSI measurement setting that includes all (L≥1) links among N CSI report settings, M RS settings, and P IM settings, L≥1 separate CSI measurement settings (one CSI measurement setting per link) can be used. In this case, one CSI measurement setting can include at least one of the following: link, timing relationship, measurement limit, and / or QCL. The detailed description of using L≥1 CSI measurement settings follows the settings for one CSI measurement setting. Using Figure 5B the example in, L = 5 separate CSI measurement settings are used.

[0147] This variant is also applicable to the second component (described later), where instead of including an RS for IM in the RS setting, a separate IM setting can be used. For example, when the UE is configured with N signaling settings, M RS settings, and P IM settings, the CSI measurement setting links each of the N signaling settings with at least one of the M RS settings and P IM settings. This is shown in Figure 5C where N = 2 (DL signaling settings indexed by 0 and 1, which are associated with Embodiments 570 and 571 respectively), M = 2 (RS settings indicated by 0 and 1, which are associated with Embodiments 575 and 576 respectively), and P = 1 (IM setting indicated by 0, which is associated with Embodiment 577).

[0148] Component 1.1 - Settings for DL CSI reporting

[0149] The following embodiments pertain to a sub-component of the settings regarding DL CSI reporting (denoted as sub-component 1.1 in the present disclosure).

[0150] In Figure 6 an example of the DL CSI reporting setting 600 is shown. Here, the CSI reporting setting first includes general setting information 601 such as (but not limited to) "mode" (whether the CSI report is periodic, aperiodic / on-demand, or semi-persistent / multi-slot), subframe or slot configuration, which includes subframe or slot offset and periodicity (only applicable to periodic and / or semi-persistent / multi-slot), and the reporting bandwidth (the number of DL frequency domain resources associated with the DL CSI report - which may include location). The "mode" configuration indicates the manner in which the DL CSI report is performed in the time domain. The "mode" takes values from {periodic, aperiodic / on-demand, semi-persistent / multi-slot}. The "mode" may also only take values from, for example, {periodic, aperiodic / on-demand} or {periodic, semi-persistent / multi-slot} or {aperiodic / on-demand, semi-persistent / multi-slot}.

[0151] In an example embodiment, a setting 600 for four CSI parameters is included: BI (beam indicator / index), RI (rank indicator), PMI (precoding matrix indicator), and CQI (channel quality indicator). In LTE, BI is equivalent to CRI (CSI-RS resource indicator) because one beam is formed per CSI-RS resource. Hereinafter, BI may refer to CRI. When all four of these CSI parameters are reported within a CSI reporting setting: the value of BI is selected, RI is calculated conditional on the current BI within the same setting, PMI is calculated conditional on the current BI and RI, and CQI is calculated conditional on the current BI, RI, and PMI. When any one of these four CSI parameters is neither reported nor fixed to a value (and thus does not need to be reported), the above adjustment rules still apply. When any one of these four CSI parameters is neither reported nor fixed to a value, the unreported CSI parameter is not a condition for the calculation of subsequent CSI parameters. For example, if BI is neither reported nor fixed to a value (set to NULL in setting 602) and a value of RI is selected, PMI is calculated conditional on the current RI, and CQI is calculated based on the current RI and PMI.

[0152] Although this embodiment includes four CSI parameters, other CSI parameters may also be included (or a subset of only these four parameters may be used, or a subset of these four parameters may be used in combination with other parameters). The use of four CSI parameters (and thus four CSI parameter settings) in the foregoing and following discussions is exemplary and for illustrative purposes.

[0153] In addition to the general setting information 601, sub-settings may be defined for each of the four CSI parameters. For example, in setting 602, the BI setting may include a possible set of values and a frequency granularity. For example, when the value set is {0, 1, 2, 3}, a 2-bit BI may be reported. When the value set is {2}, BI reporting does not have to be performed. However, the value of BI is set to 2 (i.e., the UE is configured with beam #2). When the set of values is empty (NULL), BI is not reported and BI is not used in this CSI reporting setting. If the frequency granularity is set to, for example, 20 RBs, BI is calculated and reported for each 20-RB sub-band. In 603, similar to 602, the RI setting may also include a set of possible values and a frequency granularity. For example, when the set of values is {1, 2}, a 1-bit RI may be reported. When the value set is {2}, RI reporting does not have to be performed. However, the value of RI is set to 2 (i.e., the UE will assume RI = 2 for RI calculation). When the set of values is NULL, RI is not reported and RI is not used in this CSI reporting setting.

[0154] In setting 604, the PMI setting may include a possible set of values, "type", codebook selection / configuration, and frequency granularity. The definition of this set of values and the frequency granularity is similar to that of BI or RI. The PMI "type" may include a set of possible types, such as "precoder" (which indicates the selection of a precoding vector or a matrix obtained from a codebook), "precoder group" (which indicates a group / subset of precoding vectors or a matrix obtained from a codebook), or "explicit" (which indicates explicit feedback, such as channel quantization based on a channel quantizer or a codebook, eigenvector quantization). The codebook selection / configuration may include information related to the selection of the codebook for PMI reporting.

[0155] In setting 605, the CQI setting may include CQI calculation settings and frequency granularity. The frequency granularity may be defined similarly to that of BI, RI, or PMI. The CQI calculation settings, whose possible set of values includes NULL (CQI is not reported and not used in this CSI reporting setting), may indicate the CQI calculation process. In one example of the CQI calculation process option, the CQI may be calculated by assuming data transmission along a precoder indicated / recommended by the value of PMI. In another example of the CQI calculation process option, the CQI may be calculated by assuming data transmission along multiple precoders indicated / recommended by the value of PMI, where a precoder loop is performed. That is, the precoder is changed across the frequency domain, time domain, or both. In yet another example of the CQI calculation process option, the CQI may be calculated to represent the power of the associated RS (based on the RS setting linked to this DL CSI reporting setting via the DL CSI measurement setting). In this case, the CQI may act similarly to the RSRP. Additionally, the number of bits (payload size) of the CQI may be configured as part of the CQI setting or associated with the CQI calculation settings.

[0156] The names selected above are exemplary and for illustrative purposes.

[0157] In any of the above examples, the value NULL indicating non - existence may be specified and replaced by another value providing the same function.

[0158] Settings for Component 1.2 - DL CSI Measurement

[0159] The following embodiments belong to the sub - components regarding the settings of DL CSI measurement (represented as sub - component 1.2 in this disclosure).

[0160] Examples of RS settings for DL CSI measurement are given in the following embodiments.

[0161] The RS setting may include an "RS type", which is the type of RS for DL CSI measurement. Some examples of "RS type" include DL CSI-RS, UL CSI-RS (or SRS - which is used for DL CSI measurement based on reciprocity), DL DMRS, UL DMRS, and an RS that is functionally equivalent to beam RS (BRS). In a sub-embodiment, the supported "RS type" may include at least one of the foregoing types. In another sub-embodiment, the supported "RS types" include DL CSI-RS and UL-CSI-RS (or SRS). In this sub-embodiment, two RS settings may be associated with one or two CSI report settings such that both DL CSI-RS and UL CSI-RS (or SRS) can be used for CSI calculation.

[0162] The RS setting may also include an "RS bandwidth", which indicates the amount of DL (for DL CSI-RS) or UL (for UL CSI-RS or SRS) frequency domain resources occupied by the RS transmission - the possible included locations. This may correspond to the "report bandwidth" setting of the DL CSI report setting.

[0163] The RS setting may also be configured with values including an "RS resource parameter", which may include several parameters, such as the number of RS beams / resources K (i.e., within one RS resource configuration / setting, one or more RS beams / resources may be configured - functionally similar to LTE with type B eMIMO and K≥1 NMP CSI-RS resources), K associated RS resource identifiers or indices, the number of RS ports {N1, N2,... N K} for each RS beam / resource, "RS mode", "RS power", and "RS function".

[0164] Regarding the use of the "RS resource parameter", the UE may be configured with K NZP CSI-RS resources via higher layer (RRC) signaling, while a subset of size N of the K CSI-RS (K≥N) resources may be selected or activated (for measurement or monitoring on the UE side). The selection of the subset of size N may be done via MAC control element (MAC CE) signaling or L1 DL control signaling (UL-related or DL-related DCI). In this case, if the "RS resource parameter" is included in the RS setting configured via higher layer (RRC) signaling, the number of RS resources K and the associated resource indices / identities are included in the "RS resource parameter", but the selection of the subset of size N is not performed. On the other hand, the value of N may be configured via higher layer (RRC) signaling or via MAC CE signaling (along with the selection of the size N subset).

[0165] The utilization of the “RS resource parameters” described in the previous paragraph and the subset selection of RS resources can be used for DL CSI-RS, UL CSI-RS (SRS), and / or other types of RS. Additionally, a common resource pool / set for DL CSI-RS and UL CSI-RS (SRS) can be used.

[0166] “RS pattern” indicates the RS pattern configuration in time (within one OFDM symbol) and frequency domain (spanning REs, i.e., selecting one from multiple RE patterns). Such multiple possible patterns can also include patterns with different RE densities. For a given number of RS beams / resources K, this pattern can be defined individually or jointly for each of all K≥1 RS beams / resources.

[0167] The RS pattern of an N-port RS (such as DL CSI-RS or SRS) can also correspond to the aggregation of multiple RS resources, where each resource corresponds to a smaller number of ports. For example, an N-port CSI-RS can consist of K CSI-RS resources, where the number of ports of the K CSI-RS resources are {N1, N2, …, N K}, and N1 + N2 + … + N K = N. This aggregation can be included or signaled as part of a higher layer (RRC) configuration, MAC CE, L1 DL control signaling, or a combination of the three. For example, a UE can be configured with multiple possible RS aggregation patterns and dynamically select or activate one of these aggregation patterns via MAC CE or L1 DL control signaling. Optionally, a UE can be configured with multiple possible RS aggregation patterns and dynamically select or activate a smaller subset of these aggregation patterns via MAC CE, and select and activate one of these aggregation patterns in the activated subset via L1 DL control signaling.

[0168] “RS power” indicates the RS power level relative to the power setting associated with data transmission. For example, this can be represented by the energy per RE or per EPRE (e.g., similar to LTE's P A 、P B and P C ). This RS power setting can also include ZERO, which represents a zero-power RS (similar to ZP CSI-RS for CSI-IM in LTE). Just like the “RS pattern”, for a given number of RS beams / resources K, “RS power” can be defined individually or jointly for each of all K≥1 RS beams / resources.

[0169] If only ZP CSI-RS can be used for CSI-IM, the RS for CSI-IM (interference measurement) can be distinguished from the RS region for channel measurement only by the power setting. Therefore, no further distinction between the two is required. However, if other interference measurement mechanisms (e.g., CSI-IM using NZP CSI-RS or DL DMRS) are possible, the separate RS power may not be sufficient to separate the RS for channel measurement from the RS region for interference measurement. In this case, an additional indication for IM or CSI-IM can be used. This indication can be included, for example, in the RS type (above) or RS function (below).

[0170] The "RS function" indicates whether the RS is used as "UE-specific RS" or "coverage RS" (non-UE-specific or gNB-specific or beam-specific RS). Generally, UE-specific RS can be dynamically precoded / beamformed and is specific to the UE, while non-UE-specific RS can be cell-specific or gNB-specific or beam-specific (for coverage, which can include K≥1 RS beams / resources). Additionally, when the number of RS beams / resources K>1, the "RS function" can also indicate whether beam scanning is performed across K RS beams in the time domain (e.g., across K different and consecutive OFDM symbols, within one subframe / slot / TTI or across multiple subframes / slots / TTIs). This beam scanning can be performed for DL CSI-RS or UL CSI-RS (SRS).

[0171] Such different RS functions can be enumerated. For example, "RS function" = 1 indicates the UE-specific RS function, "RS function" = 2 indicates the non-UE-specific or TRP / gNB-specific RS function (with K≥1 RS beams / resources), and "RS function" = 3 indicates using K>1 consecutive OFDM symbols to transmit K>1 RS beams / resources. For this last function, each instance of RS transmission (in one OFDM symbol) can be associated with one RS beam / resource. For DL CSI-RS, the UE will assume that the RS received via DL on K>1 consecutive OFDM symbols corresponds to K>1 DL RS beams / resources. For UL CSI-RS, the UE will assume that the RS transmitted via UL on K>1 consecutive OFDM symbols corresponds to K>1 UL RS beams / resources. Thus, beam scanning applies to both DL and UL CSI-RS.

[0172] For some cases, it can be further simplified. For example, when "RS Type" is set to UL CSI-RS, the setting of "RS function" for UL CSI measurement can be simplified by combining "UE-specific" and "non-UE-specific" into one value (e.g., "default" applies to non-scanning operations). This is because UL CSI-RS (SRS) is UE-specific. Additionally, when "RS type" is set to DL or UL DMRS (if applicable), since DMRS does not exist in subframes / slots / TTIs where UE data transmission does not exist, "RS function" is not required.

[0173] Similar to DL CSI report settings, RS settings can also include "RS mode" (CSI reports are periodic, aperiodic / on-demand, or semi-persistent / multi-slot). The "mode" configuration indicates the way of transmitting the associated RS in the time domain. "Mode" takes values from {periodic, aperiodic / on-demand, semi-persistent / multi-slot}. "Mode" may also only take values from, for example, {periodic, aperiodic / on-demand} or {periodic, semi-persistent / multi-slot} or {aperiodic / on-demand, semi-persistent / multi-slot}.

[0174] When "RS mode" is periodic or semi-persistent ("multi-slot"), the RS settings can also include "RS subframe or slot configuration", which indicates the periodicity and subframe / slot offset associated with RS transmission. Such "RS subframe or slot configuration" can be configured individually or jointly for each of all K RS beams / resources.

[0175] The names selected above are exemplary and for illustrative purposes. The RS settings in this disclosure include at least one of the above settings or sub-settings.

[0176] Regarding the use of "RS function", when the number of RS resources or beams K is greater than 1, some sub-embodiments can be described as follows.

[0177] In a sub - embodiment, the "RS function" is configured via higher - layer (RRC) signaling and is included or not included as part of the RS setup. The "RS function" indicates whether the RS is a non - UE - specific RS (coverage RS) or a UE - specific RS. In addition to this first signaling, a second signaling is performed that indicates the transmission of an RS resource (either SRS via the uplink or DL CSI - RS via the downlink) associated with one RS resource / beam identifier / indicator or multiple RS resource identifiers / indicators. This second signaling is performed via MAC CE or L1 DL control signaling (UL - related or DL - related DCI). For example, when the second signaling indicates the transmission of only one RS resource / beam, the resource / beam index can be signaled via L1 DL control signaling (e.g., carried in a DCI field). Optionally, a precoding matrix indicator (PMI) defined based on a codebook can be signaled via L1 DL control signaling (e.g., carried in a DCI field). This last option can be related to UL CSI - RS (SRS), where the PMI indicates the precoder that the UE applies to SRS transmission. On the other hand, when the second signaling indicates the transmission of multiple RS resources / beams, a beam - scanning operation is performed where the RS associated with the multiple resources / beams is transmitted across time and / or frequency units. For example, scanning N beams can indicate the transmission of N consecutive SRSs in time. A predefined scan / cyclic pattern is defined or the selected scan / cyclic pattern (from multiple options) is signaled via L1 DL control signaling (e.g., carried in a DCI field).

[0178] In another sub - embodiment, the "RS function" is configured via MAC CE, which may or may not be part of the RS settings. The "RS function" indicates whether the RS is a non - UE - specific RS (coverage RS) or a UE - specific RS. In addition to this first signaling, a second signaling is performed to indicate the transmission of an RS resource (either SRS via the uplink or DL CSI - RS via the downlink) associated with one RS resource / beam identifier / indicator or multiple RS resource identifiers / indicators. This second signaling is performed via L1 DL control signaling (UL - related or DL - related DCI). For example, when the second signaling indicates the transmission of only one RS resource / beam, the resource / beam index can be signaled via L1 DL control signaling (e.g., carried in a DCI field). Optionally, a precoding matrix indicator (PMI) defined based on a codebook can be signaled via L1 DL control signaling (e.g., carried in a DCI field). This last option can be related to UL CSI - RS (SRS), where the PMI indicates the precoder that the UE applies to SRS transmission. On the other hand, when the second signaling indicates the transmission of multiple RS resources / beams, a beam - scanning operation is performed where the RS associated with the multiple resources / beams is transmitted across time and / or frequency units. For example, scanning N beams can indicate the transmission of N consecutive SRSs in time. A predefined scanning / cyclic pattern is defined or the selected scanning / cyclic pattern (from multiple options) is signaled via L1 DL control signaling (e.g., carried in a DCI field).

[0179] Each of the above two sub - embodiments can be used for DL CSI - RS and UL CSI - RS (SRS).

[0180] When any of the above sub - embodiments is used for SRS and the second signaling utilizes L1 DL control signaling (via UL - related or DL - related DCI), the following example scenarios can be used based on the above options.

[0181] In one example (Example 1), when the DCI (UL-related or DL-related) includes an indication of the SRS resource index - separately from or as part of the SRS transmission request DCI field - in addition to the assumption of indicating the selection of 1 out of K SRS resources (or 1 out of N), the associated DCI field also includes at least one assumption of performing beam scanning on N ≤ K SRS resources (consecutive transmissions of SRS over a number of SRS resources spanning time and / or frequency units). As described above, the K SRS resources can be configured via higher layer (RRC) signaling or MAC CE. Similarly, the value of N can be configured via higher layer (RRC) signaling or MAC CE, or signaled as part of the SRS resource index indication. The number of SRS resources is denoted as N, which can be equal to K (configured via higher layer signaling) or less than K. When N < K, a subset of the K resources can be selected for the purpose of SRS triggering (in the case of aperiodic SRS) or SRS activation (in the case of semi-persistent or multi-slot SRS). An example of such a definition of the SRS transmission request (SRS trigger) DCI field for aperiodic SRS is given in Table 1.

[0182] Table 1: Example SRS Trigger Scheme

[0183]

[0184]

[0185] In another example (Example 2), the UL-related or DL-related DCI includes a PMI, which indicates the precoder that the UE uses for precoding the SRS. In this case, the PMI (referred to as PMI in the present disclosure SRS ) is used to indicate the precoder selected from a codebook. For UL-related DCI, the PMI SRSIt can be a second (additional) PMI different from the PMI for authorized UL transmission on PUSCH, or the same PMI as the PMI for authorized UL data / UCI transmission on PUSCH (referred to as TPMI in Component 2). For the latter case, the function of the PMI field (for SRS or for PUSCH data / UCI transmission) can be configured via higher layer (RRC) signaling (e.g., with an RRC parameter indicating the PMI function or a higher layer indication of the SRS type such as "non-precoded" or "precoded"), MAC CE, or indicated in the same DCI. If indicated in the same DCI, the indicator can be a separate 1-bit field (e.g., called the "PMI function" field) or jointly encoded into the PMI field. Optionally, when a single PMI is used for SRS and for authorized UL data / UCI transmission on PUSCH, the same precoder indicated by the PMI can be used (applied to) both SRS and authorized UL data / UCI transmission on PUSCH.

[0186] If UL frequency-selective precoding is configured for the UE (and thus multiple PMIs can be included in the DCI), only one PMI is used for SRS. This single PMI for SRS can be one of the multiple PMIs or a separate (additional) PMI.

[0187] In another example (Example 3), an SRS resource indicator and a PMI SRS can both be used in the DCI (DL or UL related) to request the transmission of an aperiodic SRS. The SRS resource indicator selects 1 out of N resources, while the PMI SRS indicates the precoder for the selected SRS resource. Additionally, when the SRS resource indicator indicates a request for the UE to transmit SRS in a scanning manner across N SRS resources, the PMI can indicate N precoders for the N SRS resources. The N precoders can be represented as a set of N PMIs or an indicator of a precoder group. When using a two-stage codebook (W = W1*W2, where i1 and i2 are used to indicate the two-stage precoder), the first PMI i1 can be interpreted as signaling a precoder group, where the grouping of precoders can be predefined. Thus, the interpretation of the PMI SR S field can depend on the value of the SRS resource indicator field. That is, when the SRS resource indicator signals the selection of 1 out of N SRS resources, the PMI SRS signals the selected precoder for aperiodic SRS transmission. When the SRS resource indicator signals a request for a scanning SRS transmission (across N resources), the PMI SRS signals the selected N precoder group for aperiodic SRS transmission.

[0188] As in the previous example (Example 2), the PMI SRS can be a second (additional) PMI different from the PMI used for authorized UL transmission on PUSCH, or the same PMI as the PMI (referred to as TPMI in Component 2) used for authorized UL data / UCI transmission on PUSCH. For the latter case, the function of the PMI field (for SRS or for PUSCH data / UCI transmission) can be configured via higher layer (RRC) signaling (e.g., with an RRC parameter indicating the PMI function or a higher layer indication of SRS type such as "non-precoded" or "precoded"), MAC CE, or indicated in the same DCI. If indicated in the same DCI, the indicator can be a separate 1-bit field (e.g., called the "PMI function" field) or jointly coded into the PMI field. Optionally, when a single PMI is used for SRS and for authorized UL data / UCI transmission on PUSCH, the same precoder indicated by the PMI can be used (applied) for both SRS and authorized UL data / UCI transmission on PUSCH.

[0189] If UL frequency selective precoding is configured for the UE (and thus multiple PMIs can be included in the DCI), only one PMI is used for SRS. This single PMI for SRS can be one of the multiple PMIs or a separate (additional) PMI.

[0190] The following example embodiments belong to the use cases of the first component (DL CSI framework).

[0191] In one example use case (denoted as Use Case 1.A) for DMRS-based DL dynamic or adaptive beamforming / precoding (with implicit PMI feedback), a DL CSI reporting setting of N = 1 and an RS setting of M = 1 can be used. For the DL CSI reporting setting, the value of the BI setting is set to NULL (no BI reporting), the value of the PMI setting is set to "precoder" (where PMI represents the recommended precoder obtained from the codebook), and the CQI calculation setting is configured to calculate CQI conditional on the reported RI and PMI.

[0192] For the RS setting, the "RS type" can be set to "DL CSI-RS", where the number of RS beams / resources K is set to 1. The "RS function" can be "UE-specific RS" or "non-UE-specific RS" (specific to the cell or gNB). The DL CSI measurement setting links the CSI reporting setting and the RS setting. The configuration of other settings can be flexibly selected according to the gNB implementation.

[0193] In one example use case (denoted as Use Case 1.B) for DL beam cycling (with implicit PMI feedback) based on DMRS, DL CSI reporting settings with N = 1 and M = 1 RS settings can be used.

[0194] For the DL CSI reporting settings, the value of the BI setting is set to NULL (no BI reporting), the value of the PMI setting is set to "precoder group" (where PMI represents the recommended precoder group obtained from the codebook), and assuming the UE receives DL data transmissions along a set of precoders that cycle in the time domain and / or frequency domain, the CQI calculation settings are configured to calculate the CQI conditional on the reported RI and PMI.

[0195] For the RS settings, the "RS type" can be set to "DL CSI-RS", where the number of RS beams / resources K is set to 1. The "RS function" can be "UE-specific RS" or "non-UE-specific RS" (specific to the cell or gNB).

[0196] The DL CSI measurement settings link the CSI reporting settings with the RS settings. The configuration of other settings can be flexibly selected according to the gNB implementation.

[0197] In one example use case (denoted as Use Case 1.C) for DL beam management with K > 1 RS beams, DL CSI reporting settings with N = 1 and M = K RS settings can be used.

[0198] For the DL CSI reporting settings, the value of the BI setting is set to NULL (no BI reporting), the value of the RI setting is set to NULL (no RI reporting), the value of the PMI setting is set to NULL (no PMI reporting), and the CQI calculation settings are configured to be similar to the RS signal power of LTE RSRP.

[0199] For the RS settings, the "RS type" can be set to "DL CSI-RS", where the number of RS beams / resources is K. The "RS function" can be "non-UE-specific RS" (specific to the cell or gNB) or optionally, "beam scanning" (where K DL RS beams / resources are sent using K consecutive OFDM symbols).

[0200] The DL CSI measurement settings link N = 1 CSI reporting settings with M = K > 1 RS settings. The configuration of other settings can be flexibly selected according to the gNB implementation.

[0201] In one example use case for virtual sectorization with K > 1 RS beams (denoted as use case 1.D), similar to LTE Category B with K > 1, an N = 1 DL CSI reporting setting and an M = K RS setting can be used.

[0202] For the DL CSI reporting setting, the values of the BI setting are set to {0, 1,..., K - 1}.

[0203] For the RS setting, the "RS type" can be set to "DL CSI-RS", where the number of RS beams / resources is K. The "RS function" can be "non-UE-specific RS" (cell- or gNB-specific).

[0204] The DL CSI measurement setting links the N = 1 CSI reporting setting with the M = K > 1 RS setting. The configuration of other settings can be flexibly selected according to the gNB implementation.

[0205] In one example use case for explicit (quantized channel) feedback for "partial port" DL CSI-RS and UE-specific beamforming CSI-RS (denoted as use case 1.E), an N = K + 1 DL CSI reporting setting and an M = K + 1 RS setting can be used.

[0206] For the first K DL CSI reporting settings, the values of the BI setting are set to NULL (no BI reporting), the values of the PMI setting are set to "explicit" (where PMI represents the parameterization of the recommended quantized channel obtained from a quantized codebook), and the CQI calculation setting is set to NULL (no CQI reporting). For the last DL CSI reporting setting, the values of the BI setting are set to NULL (no BI reporting), the values of the PMI setting are set to "precoder" (where PMI indicates the recommended precoder obtained from another codebook), and the CQI calculation setting is configured to calculate CQI conditional on the reported RI and PMI.

[0207] For the first K RS settings, the "RS type" can be set to "DL CSI-RS", and the number of RS beams / resources is K (where K represents the number of partitions, and N1 + N2 + … + N K is the total number of DL antenna ports for DL transmission). The "RS function" can be "non-UE-specific RS" (cell- or gNB-specific). For the last RS setting, one RS beam / resource can be used to set the "RS type" to "DL CSI-RS". The "RS function" can be "UE-specific RS". The last RS setting can be configured in such a way that the associated RS is transmitted more frequently than the RS associated with the first K RS settings.

[0208] The DL CSI measurement setup links the first K CSI report setups to the first K RS setups in a one-to-one manner. It also links the last CSI report setup to the last RS setup. The configuration of other setups can be flexibly selected according to the gNB implementation.

[0209] In one example use case (denoted as use case 1.F) of DMRS-based DL dynamic beamforming for assuming DL-UL reciprocity (TDD), N = 1 DL CSI report setup and M = 2 RS setups can be used.

[0210] For the DL CSI report setup, the value of the BI setup is set to NULL (no BI reporting), the value of the PMI setup is set to NULL (no PMI reporting), and the CQI calculation setup is configured to calculate the CQI conditional on the reported RI.

[0211] For the first RS setup, the "RS type" can be set to "DL CSI-RS", where the number of RS beams / resources K is set to 1. The "RS function" can be either "UE-specific RS" or "non-UE-specific RS" (cell or gNB-specific). For the second RS setup, the "RS type" can be set to "UL CSI-RS (SRS)", where the number of RS beams / resources K is set to 1. The "RS function" can be either "UE-specific RS" or "non-UE-specific RS" (cell or gNB-specific).

[0212] The DL CSI measurement setup links a single CSI report setup to two RS setups. In this case, the gNB can use the second RS setup (associated with UL CSI-RS / RS) to calculate the DL precoder for DL data transmission.

[0213] The configuration for other setups can be flexibly selected according to the gNB implementation.

[0214] Optionally, N = 1 DL CSI report setup and M = 1 RS setup can be used. In this case, the use of the second RS setup (either DL CSI-RS or SRS) is configured separately from the DL CSI report setup. Thus, the DL CSI measurement setup links a single CSI report setup to a single RS setup of DL CSI-RS.

[0215] Component 2 - UL CSI Framework

[0216] For a second component (i.e., the UL CSI acquisition framework), the UL CSI framework is partially designed to facilitate UL CSI acquisition at the gNB / TRP. This involves UL CSI measurement of UL signals at the gNB / TRP, UL CSI measurement of DL signals at the UE (for DL-UL reciprocity-based operations), or both. Some example embodiments are given below.

[0217] In one example embodiment, for a single UE, the UL CSI framework includes at least one "signaling setting", at least one "RS setting" (which includes at least one RS for UL CSI measurement), and a "UL CSI measurement setting". The "signaling setting" configures the necessary signaling for the UE, either DL signaling (via, e.g., DL data or control channels) or UL (via, e.g., UL data or control channels). The RS setting configures one or more RS resources for the UE for UL CSI measurement and calculation. For example, one of the configured RSs can be a DL or UL CSI-RS, which also includes CSI-IM (thus a zero-power CSI-RS) as a special case. The CSI measurement setting provides a link / coupling between the CSI report and the RS setting.

[0218] It should be noted that the above specifications (signaling setting, RS setting, and CSI measurement setting) are exemplary and for illustrative purposes only. Other specifications can also be used to represent the functions.

[0219] In a variation of the above embodiment, the "signaling setting" can also be divided into two settings: a "DL signaling setting" and a "UL signaling setting".

[0220] The "RS setting" for UL CSI measurement can be the same as the "RS setting" for DL CSI measurement. Optionally, a separate RS setting can be defined for UL CSI measurement, which uses a subset of the features or parameters of the RS setting for DL CSI measurement.

[0221] For example, when the UE is configured with N signaling settings and M RS settings, the CSI measurement setting links each of the N signaling settings with at least one of the M RS settings. This is shown in Figure 7 where N = 2 (DL signaling settings indexed by 0 and 1, which are associated with embodiments 710 and 711 respectively) and M = 3 (RS settings indexed by 0, 1, and 2, which are associated with embodiments 720, 721, and 722 respectively).

[0222] In this example, the UL CSI measurement setup can be described as follows. Two signaling setups and three RS setups are linked to the CSI measurement setup 730. In this example, signaling setup 0 is linked to RS setup 0, and signaling setup 1 is linked to RS setups 1 and 2. The first link (1-to-1) applies to typical UL scenarios, while the second link (1-to-2) applies to TDD scenarios where DL-UL reciprocity can be exploited to achieve higher-resolution precoding / beamforming at the UE.

[0223] In addition to the above links, the timing relationship between a signaling and its corresponding RS can be included in the CSI measurement setup. For example, when signaling setup 1 (UL signaling) is linked to RS setup 2 (DL CSI-RS), the UE behavior can be defined as follows. When the UE receives the RS associated with RS setup 2 in subframe or slot n, the UE will report the CSI associated with signaling setup 1 in subframe or slot n+D 1-2 where the parameter D 1-2 is configurable. In Figure 7 the example depicted, signaling setup 1 can share the same design as the DL CSI reporting setup in component 1.1 above.

[0224] Furthermore, especially related to the UL signaling setup (and thus the same as the DL CSI reporting setup), the measurement limitations associated with each link (not only the location but also the extent of measuring CSI in the time domain, frequency domain, or both) can be included in the CSI measurement setup.

[0225] In addition, quasi-colocation (QCL) between more than one antenna port can be included in the signaling setup.

[0226] At least one (or a combination of several) of the above example elements of the signaling setup can be selected to form the signaling setup for UL CSI measurement for DL or UL.

[0227] In a variation of the above embodiment, instead of using one UL CSI measurement setup that includes all (L≥1) links between N signaling setups and M RS setups, L≥1 separate UL CSI measurement setups (one CSI measurement setup per link) can be used. In this case, one CSI measurement setup can include at least one of the following: link, timing relationship, measurement limitation, and / or QCL. The detailed description of using L≥1 CSI measurement setups follows the setup for one CSI measurement setup.

[0228] The above settings can be configured for the UE via higher layer (RRC) signaling, or MAC control element (MAC CE), or L1 control signaling (DL control signaling via the DL control channel). There are several possibilities. First, all of the above settings (signaling settings, RS settings, and UL CSI measurement settings) can be configured via higher layer (RRC) signaling or MAC control element (MAC CE). Second, the signaling settings and RS settings can be configured via higher layer (RRC) signaling, while the UL CSI measurement settings can be configured via MAC control element (MAC CE). Third, the signaling settings and RS settings can be configured via higher layer (RRC) signaling, while the UL CSI measurement settings can be configured via L1 control signaling (DL control signaling via the DL control channel). Fourth, the signaling settings and CSI measurement settings can be configured via higher layer (RRC) signaling, while the RS settings can be configured via L1 control signaling (DL control signaling via the DL control channel).

[0229] The UL transmission scheme / method is configured separately. How the UL transmission scheme / method is used together with the UL CSI-related settings is an implementation of the gNB.

[0230] The following embodiments belong to a sub-component regarding the settings of DL or UL signaling (denoted as sub-component 2.1 in the present disclosure).

[0231] In one exemplary embodiment, the "signaling settings" include the parameter "signaling type" (a term selected as an example), which can be configured as "UL signaling" or "DL signaling" (values selected as examples). UL signaling includes using DL CSI reports (which are performed via the UL channel) for UL CSI acquisition at the gNB. Thus, the signaling settings configuration can follow the configuration in component 1.1 (exactly or loosely). DL signaling includes signaling of UL transmission parameters (such as transmit precoding matrix indicator, transmit rank indicator, or other relevant UL CSI parameters) via the DL channel (similar to LTE UL-related DCI carried via the DL control channel or control information carried via the DL data channel).

[0232] In another embodiment, the "signaling settings" can be further divided into two settings: "DL signaling settings" and "UL signaling settings". Their interpretations or designs are similar to the above embodiment. However, in this case, the parameter "signaling type" is unnecessary.

[0233] In yet another embodiment, only DL signaling settings are supported.

[0234] Although the UL signaling settings can strictly follow component 1.1, the DL signaling settings 800 can adopt as Figure 8A simpler form is shown, where the transmit beam indicator (TBI) setting is configured in 801, the transmit rank indicator (TRI) setting is configured in 802, and the transmit PMI (TPMI) setting is configured in 803. How to interpret each of these three settings is similar to the DL CSI reporting settings in Component 1.1 - except that TBI, TRI, and TPMI are UL transmission parameters rather than CSI parameters recommended by the UE. These settings affect, for example, the size of UL-related DCI and the need for additional DL control signaling (e.g., for signaling subband TBI, TRI, and / or TPMI to support UL frequency-selective precoding).

[0235] Although the DL signaling setting 800 includes three DL signaling parameters, other signaling parameters may also be included (or only a subset of these three parameters may be used, or a subset of these parameters combined with other parameters). The use of three signaling parameters (and thus three DL signaling parameter settings) in the foregoing and subsequent discussions is exemplary and for illustrative purposes.

[0236] Regarding the TBI setting, this can be utilized (signaled) when the UE is configured to transmit K > 1 UL CSI-RS or SRS beams / resources. In this case, the gNB measures those K "sounding" beams and signals to the UE the RS beam / resource on which the UE will transmit its UL data (selected by the gNB). The TBI signaling can be turned off by setting the TBI value to NULL. Similar to Component 1, further down-selection of N from the K configured SRS resources can be performed. Although the K resources can be configured via higher layer (RRC) signaling, N of the K resources can be configured via MAC CE or L1 DL control signaling (via DCI).

[0237] As described in Component 1, the SRS resource indicator field can be included in UL-related DCI. This field can be separate from the TBI, or the same field as the TBI, but can be interpreted differently according to additional assumptions. This additional assumption can be part of the TBI, a separate one-bit DCI field, or part of the SRS transmission request field.

[0238] Regarding the TRI setting, the value of TRI determines the number of UL data layers transmitted by the UE. When UL SU-MIMO operation is not configured for the UE, the TRI signaling can be turned off by setting the TRI value to NULL (or, optionally, setting it to {1}).

[0239] Regarding the TPMI configuration, the "type" parameter can be used to configure the UE using "precoder", "precoder group" (for precoder cycling), or "explicit" - similar to the DL CSI reporting configuration in Component 1.1. However, for UL MIMO, "explicit" may not be required. Therefore, the "type" parameter can be set to "precoder" or "precoder group".

[0240] As described in Component 1, the PMI SRS field can be included in the UL-related DCI. This field can be separate from the TPMI, or the same field as the TPMI, but can be interpreted differently based on additional assumptions. This additional assumption can be part of the TPMI, a separate one-bit DCI field, or part of the SRS transmission request field.

[0241] The names chosen above are exemplary and for illustrative purposes.

[0242] In any of the above examples, the value NULL indicating non-existence can be specified and replaced by another value providing the same function.

[0243] The following exemplary embodiments relate to the usage of a second component (UL CSI framework).

[0244] In one example use case for DMRS-based UL SU-MIMO (denoted as Use Case 2.A), an N = 1 signaling configuration (set to "DL signaling") and an M = 1 RS configuration can be used.

[0245] For the DL signaling configuration, if conventional dynamic beamforming is configured, the value of the TBI configuration is set to NULL (no BI reporting) and the value of the TPMI configuration is set to "precoder" (where the TPMI indicates a specified precoder obtained from the codebook). If precoder cycling is configured, the value of the TPMI configuration is set to "precoder group" (where the TPMI indicates a specified precoder group obtained from the codebook). The TPMI frequency granularity can indicate whether frequency non-selective or frequency selective precoding / beamforming is configured.

[0246] For the RS configuration, "RS type" can be set to "UL CSI-RS / SRS", where the number of RS beams / resources K is set to 1. "RS function" can be "default".

[0247] The UL CSI measurement configuration links the DL signaling configuration with the RS configuration. The configuration of other settings can be flexibly selected according to the gNB implementation.

[0248] In one example use case (denoted as Use Case 2.B) for DMRS-based UL SU-MIMO with DL-UL reciprocity (TDD), an N = 1 signaling setting (set to "DL signaling") and an M = 2 RS setting can be used.

[0249] For the DL signaling setting, if conventional dynamic beamforming is configured, the value of the TBI setting is set to NULL (no BI reporting) and the value of the TPMI setting is set to "precoder" (where TPMI indicates a specified precoder obtained from the codebook). If precoder cycling is configured, the value of the TPMI setting is set to "precoder group" (where TPMI indicates a specified precoder group obtained from the codebook). The TPMI frequency granularity can indicate whether frequency non-selective or frequency selective precoding / beamforming is configured.

[0250] For the first RS setting, the "RS type" can be set to "UL CSI-RS / SRS", where the number of RS beams / resources K is set to 1. The "RS function" can be "default".

[0251] For the second RS setting, the "RS type" can be set to "DL CSI-RS", where the number of RS beams / resources K is set to 1. The "RS function" can be "UE-specific" or "non-UE-specific". Or if the two values are combined to "default", it can be set to "default". The purpose of this second RS setting is to assist UE precoder / beamforming. For example, thus, the UE can refine the beamforming / precoding resolution signaled in the DL TPMI.

[0252] The UL CSI measurement setting links the DL signaling setting and the RS setting. The configuration of other settings can be flexibly selected according to the gNB implementation.

[0253] Optionally, an N = 1 signaling setting (set to "DL signaling") and an M = 1 RS setting (set to "ULCSI-RS / SRS") can also be set, while using another RS setting set to "DL CSI-RS" without linking it to the DL signaling setting.

[0254] In one example use case (denoted as Use Case 2.C) for UL beam management with K > 1 UL CSI-RS (SRS) beams - which is related to the non-reciprocity scenario - an N = 1 DL signaling setting and an M = K RS setting (set to "ULCSI-RS / SRS") can be used.

[0255] For the DL signaling setting, the value of the TBI setting is set to {0, 1,..., K - 1}.

[0256] For the RS setting, the "RS type" can be set to "UL CSI-RS / SRS", where the number of RS beams / resources is K. The "RS function" can be "default" or optionally "beam scanning" (where K UL CSI-RS / SRS beams / resources are transmitted using K consecutive OFDM symbols).

[0257] The UL CSI measurement setting links the N = 1 DL signaling setting with the M = K > 1 RS setting. The configuration of other settings can be flexibly selected according to the gNB implementation.

[0258] For the third component (i.e., another DL CSI acquisition framework), several exemplary embodiments are given below.

[0259] In some embodiments, a flexible CSI reporting framework is supported in advanced communication systems such as 5G or New Radio (NR). In this framework, the UE is configured with a CSI reporting mode or configuration, which includes the following modules.

[0260] The first module 0 includes CSI-RS and CSI-IM configurations. The CSI reporting configuration includes K downlink reference signals (CSI-RS) for estimating channel state information (CSI), where K ≥ 1. The time-domain and frequency-domain CSI-RS patterns in the PRBs where the CSI-RS are located can also be configured by the TRP. For all K CSI-RS, the pattern can be the same, or for a subset / all of them, it can be different. The configurable set of time-frequency CSI-RS patterns may or may not include the CSI-RS patterns for LTE (up to Release 14).

[0261] The multiplexing of the K CSI-RS can also be configured by the TRP. For example, one of the following time-domain (subframe / slot index) or / and frequency-domain (PRB index) multiplexings can be configured. The K CSI-RS can be multiplexed in consecutive or non-consecutive subframes / slots in the time domain. Examples showing two time-domain multiplexing patterns are shown respectively in Figure 9A and Figure 9B are shown. The K CSI-RS can also be multiplexed in the frequency domain. Figure 9C Shows an example showing frequency-domain multiplexing, where each CSI-RS is transmitted in at least one PRB. Another example of frequency-domain multiplexing is that in some PRBs, one or more CSI-RS can be transmitted in the same PRB. The K CSI-RS can also be multiplexed in the time domain and frequency domain. The TRP can configure a combination of the first two multiplexing methods for CSI-RS transmission.

[0262] Each CSI-RS can be configured by the TRP or the network individually and flexibly as cell-specific, or TRP-specific, or UE-specific, or non-UE-specific. For example, K CSI-RSs can all be UE-specific, or all non-UE-specific, or a mixture of UE-specific and non-UE-specific. In another example, K CSI-RSs are configured to be transmitted from a single TRP, or optionally, a subset of them can be transmitted from one TRP while another subset can be transmitted from a different TRP.

[0263] Each CSI-RS can also be configured with the number of ports associated therewith. The configuration of the number of ports can be individual or common for all K CSI-RSs, or individual for a subset of the K CSI-RSs and common for the remaining CSI-RSs.

[0264] In addition to CSI-RS, the UE can also be configured with CSI-IM resources for interference measurement. The configuration of CSI-IM regarding the time-domain and frequency-domain positions within a PRB, regarding the time-domain and frequency-domain multiplexing methods, regarding cell / TRP / UE / non-UE-specific characteristics, and regarding the number of transmission ports can be similar to the CSI-RS mentioned above.

[0265] The CSI-RS or / and CSI-IM transmission can also be configured to be periodic after each T sub-frame / slot or aperiodic on demand. For example, a subset of K CSI-RSs can be transmitted periodically, and another subset can be transmitted aperiodically.

[0266] The second module includes CSI reporting or MIMO type configuration (referred to as eMIMO type configuration in this disclosure).

[0267] Each CSI-RS can be associated with the same or different CSI reporting or eMIMO types. Examples of eMIMO types include Class A, Class B, K>1 and Class B, K=1 as in LTE Rel.13, or new eMIMO-Types in Rel.14, if any.

[0268] The CSI report generated based on each CSI-RS can be configured to include at least one of the CSI contents, such as precoding matrix indicator (PMI), channel quality indicator (CQI), rank indicator (RI), CSI resource indicator (CRI), beam indicator (BI), beam group indicator (BGI), and linear combination coefficient indicator (LCCI). The time-domain and frequency-domain granularity of the CSI can also be further configured. The reporting of the CSI components in each CSI report can be fixed (e.g., WB or SB) or configured to be one of WB and SB.

[0269] K CSI reports, or a subset of the K CSI reports, may be configured to be generated independently or dependently. For example, L (L≤K) CSI reports generated based on L CSI-RSs may be configured to be generated independently of each other, and the remaining K-L CSI reports, generated based on the remaining K-L CSI-RSs, may be configured to be generated dependently.

[0270] In the proposed flexible CSI report configuration, the CSI type may also be configured as one of implicit, explicit, analog, or semi-dynamic.

[0271] If the CSI type is configured as implicit, at least one of CQI / PMI / RI / CRI is reported based on an LTE-like codebook. For example, a single-stage codebook such as an LTE Rel.8 2-Tx, Rel.10 4-Tx, and Rel.12 Class B codebook is used to report CSI including a single PMI. In another example, a two-stage codebook W = W1 W2 such as an LTE Rel.10 8-Tx, Rel.12 4-Tx, Rel.13 Class A codebook is used to report a pair of PMIs (PMI1, PMI2). In this two-stage codebook, the first PMI (PMI1) indicates a broadband beam group, and the second PMI (PMI2) selects a beam from the indicated beam group and determines the in-phase value of two polarizations (assuming cross-polarized antenna ports are used at the TRP). In yet another example, the two-stage codebook is a linear combination (LC) codebook, where the first PMI (PMI1) indicates a broadband beam group, and the second PMI (PMI2) indicates the linear combination coefficient (and in-phase) for combining the beams in the indicated beam group..

[0272] If the CSI report is configured to be explicit, the CSI corresponds to at least one of all the information of the channel, the principal eigenvector (with or without the corresponding eigenvalue), and the covariance matrix. To reduce the overhead and complexity of explicit CSI reporting, a simplified form of explicit CSI may be configured to be reported. For example, a linear combination of basis vectors representing explicit CSI such as an eigenvector may be configured to be reported as reduced-dimension explicit CSI instead of full explicit CSI.

[0273] If the CSI report is configured to be reported for semi-dynamic beamforming, the reported CSI indicates information about a set of beams. For example, the CSI may be configured to be reported using the first-stage W1 codebook of the two-stage codebook used for implicit CSI reporting. In this example, only PMI1 indicating the broadband beam group is reported in the CSI.

[0274] The third module includes a CQI calculation configuration.

[0275] In the proposed flexible CSI reporting configuration, for each CSI report or eMIMO type, a CQI report can also be configured, where the reported CQI can be wideband (WB) or subband (SB). If the CQI is configured to be reported in the CSI report, the CQI calculation method can also be configured. The configuration of CQI calculation can be related to the transmission scheme or independent of the transmission scheme. For example, the configured CQI calculation method can correspond to one of the transmission schemes such as dynamic beamforming, semi-dynamic beamforming, or transmit diversity-based transmission, as in LTE. For example, if the CQI calculation method corresponds to dynamic beamforming, a single precoder or beamformer is assumed in the CQI calculation (WB or each SB). If the CQI calculation method corresponds to semi-dynamic beamforming, multiple precoders or beamformers are considered in the CQI calculation, where multiple precoder cycles can be assumed, e.g., across RBs or REs. If the CQI calculation method corresponds to transmit diversity-based transmission, transmit diversity schemes such as space-frequency block coding (SFBC) and frequency-switching transmit diversity (FSTD) can be assumed to calculate the CSI. As another example, the configured CQI calculation method can be independent of the transmission scheme and be directly configured by the TRP. For example, the CQI calculation method can be configured as a single precoder or multiple precoders that cycle across RBs or REs.

[0276] The fourth module includes a rank indicator (RI) indicator. In the proposed flexible CSI reporting configuration, for each CSI report or eMIMO type, an RI report can also be configured. The configuration of the RI can be independent of the configuration of other CSI report components or can depend on the configuration of other CSI report components. For example, if the CSI type is configured to be implicit, the RI is configured to be reported in the CSI report. In another example, if the CSI type is configured to explicitly represent the downlink channel, the RI report is not configured. In yet another example, if the CSI type is configured to be semi-dynamic, the RI report is configured or not configured (e.g., in the latter case RI = 1).

[0277] In the flexible CSI reporting configuration scheme, each of the K CSI reports or eMIMO types in the fifth module can be configured by the TRP to be one of periodic, semi-persistent, or aperiodic. Similar to LTE, an example of a periodic CSI report is a PUCCH-based report, and an example of an aperiodic CSI report is a PUSCH-based report.

[0278] If the CSI report type is configured to be periodic, the duty cycle (or period) in the time domain granularity can also be configured by the TRP. Additionally, if the CSI report includes multiple CSI components configured to be reported separately in multiple periodic CSI report instances, for each CSI component, the periodicity and offset are also configured, where the periodicity and offset of one CSI component such as CQI / PMI can be defined relative to another CSI component such as RI.

[0279] If the CSI report type is configured to be aperiodic, the time domain (subframe or slot) and frequency domain (PRB) positions for reporting the CSI are also configured by the TRP.

[0280] The sixth module includes panel configuration. In a flexible CSI report configuration scheme, the number of antenna panels at the TRP can be configured by the TRP and indicated to the UE to derive / report the CSI report. The configuration of the number of panels can correspond to a single panel or multiple panels. For example, for a millimeter wave 5G or NR communication system, multiple (e.g., 4) antenna panels can be arranged in a 2D (e.g., 2 by 2) structure, and this arrangement can be indicated to the UE to assist in generating the CSI report. In one example of multiple panels, the UE is also configured to separately derive or / and report the CSI for each panel. In another example, the UE is configured to jointly derive or / and report the CSI for each group.

[0281] The seventh module includes CSI report BW configuration. In a flexible CSI report configuration scheme, the bandwidth or set of (contiguous or distributed) PRBs corresponding to the CSI report can be configured by the TRP and indicated to the UE. The configuration of the CSI report bandwidth can be the entire bandwidth or a part of the bandwidth. For example, the TRP can indicate that a specific UE reports the CSI on a desired part of the bandwidth, and can indicate to another UE to report the CSI on another part of the bandwidth. This bandwidth information is configured by the TRP and helps the UE generate the corresponding CSI report.

[0282] The eighth module includes RF beamforming configuration. In a flexible CSI report configuration scheme, if the TRP has a hybrid beamforming architecture (e.g., 5G or NR millimeter wave communication system), the CSI reporting process for TRP RF beamforming can be configured to be independent of the CSI reporting process for digital beamforming, or in conjunction with the CSI reporting process for digital beamforming.

[0283] If the CSI reporting process for TRP RF beamforming is configured to be independent of the CSI reporting process for digital beamforming, two separate CSI reporting processes are performed. The CSI reporting process associated with digital beamforming is similar to LTE, and the CSI reporting process associated with RF beamforming is an independent process.

[0284] If the CSI reporting procedure for TRP RF beamforming is configured to be joint with the CSI reporting procedure for digital beamforming, only a single CSI reporting procedure is performed, where, for example, RF beam selection is first performed in the joint procedure, followed by digital beamforming.

[0285] In a flexible CSI reporting configuration scenario, if the UE also has a hybrid beamforming architecture, the CSI reporting procedure for UE RF beamforming can also be configured. The UE RF beamforming configuration can be independent or joint with digital beamforming, similar to TRP RF beamforming. The UE RF beamforming configuration can be independent or joint with the TRP RF beamforming configuration.

[0286] The ninth module includes configurations belonging to network coordination, i.e., the setup for a single or multiple TRPs. In a flexible CSI reporting configuration scenario, the configuration of CSI reporting can come from a single or multiple TRPs. If the configuration comes from multiple TRPs, the CSI configuration method \ CSI derivation method and CSI reporting method in each configuration component can also be configured to be independent of each other, or joint with a subset or all other configuration components.

[0287] In one embodiment, the UE is configured with a CSI reporting mode or configuration that includes all or some of the above CSI configuration modules 0 - 8.

[0288] In another embodiment, some of the above CSI configuration modules 0 - 8 can be common to all possible CSI configurations. For example, beam group selection can be common to all CSI reporting modes.

[0289] In another embodiment, the above CSI configuration modules 0 - 8 can be divided into three groups for the CSI reporting procedure: CSI-RS configuration, CSI measurement and generation configuration, and CSI reporting or eMIMO type configuration. The dependencies of the three groups or subsets of the three groups can be configured to be coupled or decoupled. FIG. 1000 showing the relationship of the groups is shown in Figure 10 is shown.

[0290] In another embodiment, the CSI measurement and generation configuration includes a mapping that links between N CSI reporting configurations and M CSI-RS configurations, where N and M can be different and do not need to be one-to-one. For example, Figure 11Shows an example of CSI-RS and CSI report mapping for N = 3 (n = 0, 1, 2) and M = 2 (m = 0, 1), where the links are configured such that: the CSI reports configured in settings 0 and 1 are calculated based on CSI-RS measurements configured in CSI-RS setting 0 (0→0 and 1→0 in the figure), while the CSI report configured in setting 2 is calculated based on CSI-RS measurements configured in CSI-RS setting 1 (2→1 in Figure 1100). These links can be included in the CSI measurement configuration. The CSI measurement and generation configuration can also include measurement limits or QCL (if applicable) for each mapping link. For example, the limits can include the timing relationship between the CSI report and the CSI-RS, which is optionally part of the transmission scheme configuration (e.g., in LTE).

[0291] The following discussion focuses on CSI report or eMIMO type configurations.

[0292] In another embodiment, the CSI report configuration can include a mode (periodic, aperiodic, or semi-persistent), subframe or slot configuration in the period and offset, and CSI parameter configuration (e.g., BI, RI, PMI, and CQI). An example showing this configuration is shown in Figure 6 setting 600. In this example, if the BI report is not configured as NULL, the RI is calculated conditional on the reported (or hypothesized) BI. Similarly, the PMI is calculated based on the reported (or hypothesized) BI and / or RI. And the CQI is calculated conditional on the reported (or hypothesized) BI, RI, and / or PMI.

[0293] In another embodiment, the configuration of CSI report parameters included in the module is decoupled from the transmission scheme. How to use the transmission scheme / method in combination with CSI-related settings is a TRP implementation. Regardless of the transmission scheme, the CSI report parameters can be configured independently or dependently of each other. For example, the UE can configure CSI report parameters, including:

[0294]

[0295] In this example, the UE can be configured with explicit feedback and report full channel information. As another example, the UE can configure CSI report parameters, including:

[0296]

[0297] In this example, the UE can be configured with explicit feedback and report eigenvectors. As another example, the UE can configure CSI report parameters, including:

[0298]

[0299] In this example, the UE can be configured with implicit feedback. For another example, the UE can be configured with CSI reporting parameters, including:

[0300]

[0301] In this example, the UE can be configured with semi-dynamic / semi-open loop feedback. For another example, the UE can be configured with two sets of CSI reporting parameters, as follows:

[0302]

[0303]

[0304]

[0305] In this example, the UE can be configured with type A eMIMO type reporting using a first configuration, and type B eMIMO type reporting using a second configuration. The dependency relationship between the two configurations is also configurable. For example, the two configurations can be configured to be transparent to each other. For another example, the second configuration can be configured to depend on the first configuration.

[0306] In another embodiment, some configurable CSI reporting modes may only support a subset of the combinations of the above modules 0-8, which means that the configuration of a module can depend on the configuration of other modules. This dependency can avoid functional duplication in CSI reporting configurations. For example, if the UE is configured with an explicit CSI type (module 1), it may not be configured with a periodic CSI reporting type, but only with an aperiodic CSI reporting type (module 4). For another example, the periodic or semi-persistent CSI reporting type (module 4) may only be configured with a broadband report (module 6), and the aperiodic CSI reporting type (module 4) may only be configured with a subband report (module 6).

[0307] In another embodiment, if a CSI reporting configuration does not configure one of modules 0-8 (module X) and a CSI that requires module X is derived, the default configuration of module X can be assumed to derive the CSI report. For example, if the TRP does not configure an RI report (module 3), the UE can assume that the RI default configuration is 1 and generate a CSI report.

[0308] In another embodiment, the UE may only be able to support a subset of the set of all CSI reporting configurations, and the TRP knows the CSI reporting capabilities of the UE. The TRP can only configure the CSI reporting configuration within the capabilities of the UE. For example, the UE may not be able to perform explicit (high-resolution) CSI reporting (module 1), so the TRP should not configure this UE with any CSI reporting configuration that includes an explicit CSI type.

[0309] In another embodiment, the UE may be able to support multiple CSI reporting configurations, and the TRP knows this. Then, the TRP may indicate one of the supported CSI reporting configurations to the UE, and the UE will generate a CSI report based on the configured CSI reporting configuration. For example, the UE may support both explicit and implicit CSI types, and the TRP schedules the UE using SU transmission and configures it using the implicit CSI type. Thus, the UE will generate a CSI report corresponding to the implicit CSI type even though it has the ability to generate a CSI report corresponding to the explicit CSI type.

[0310] In another embodiment, after collecting CSI reports of multiple modules including CSI reporting configurations, a transmission scheme or method may be selected, examples of which may include spatial multiplexing (e.g., beamforming and precoder cycling), and transmit diversity (e.g., SFBC).

[0311] Figure 12 A flowchart showing a process 1200 of configurable CSI reporting is shown. After the TRP knows the UE's capabilities on CSI reporting, it configures the CSI reporting process, including CSI-RS / CSI-IM configuration, CSI measurement and calculation configuration, CSI reporting or eMIMO type configuration, and indicates the configuration to the UE. The UE measures and generates a CSI report based on the configuration and gives the configured CSI report to the TRP. The TRP schedules the next transmission based on the CSI report.

[0312] In another embodiment, a flexible CSI reporting configuration may be signaled by a single or multiple TRPs to quickly obtain CSI. For example, the CSI reporting configuration may be configured by a single TRP, where the CSI reporting configuration information is sent to the target UE via PDCCH in DCI. In another example, the CSI reporting configuration may be configured by multiple TRPs, where the CSI reporting configuration information is sent to the target UE via PDCCH in the DCI of each TRP.

[0313] In another embodiment, the flexible CSI reporting configuration may also be signaled by a higher layer in a semi-static manner. For example, the CSI reporting configuration may be configured by radio resource control (RRC).

[0314] Figure 13 A flowchart showing an example method 1300 according to an embodiment of the present disclosure is shown, where the UE receives configuration information for channel state information (CSI) calculation and reporting. For example, method 1300 may be executed by UE 116.

[0315] Method 1300 begins with the UE receiving configuration information for channel state information (CSI) calculation and reporting, where the configuration includes N ≥ 1 CSI report settings, M ≥ 1 reference signal (RS) settings, and measurement settings (step 1301). The measurement settings include a link between the CSI report settings and the RS settings, where CSI reports associated with the CSI report settings are calculated based on measurements of reference signals (RSs) associated with the RS settings. Thus, the link determines the dependence of the CSI measurements and calculations on the RSs associated with the RS settings. The RS settings are configured for channel measurements or interference measurements. The CSI report settings are configured to report CSI reports in a periodic, aperiodic, or semi-persistent manner. Similarly, the RS settings are associated with CSI-RSs, which are configured to be measured in a periodic, aperiodic, or semi-persistent manner. The CSI report settings include CSI parameter settings for at least a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), or a CSI-RS resource indicator (CRI). The configuration information is received via higher layer signaling. The UE decodes the CSI configuration information (step 1302). The CSI reports are calculated using the decoded information (step 1303). The calculated CSI reports are then transmitted on an uplink (UL) channel (step 1304).

[0316] Figure 14 A flowchart of an example method 1400 in accordance with an embodiment of the present disclosure is shown, where a BS generates configuration information for channel state information (CSI) calculation and reporting for a UE (labeled UE-k). For example, method 1400 may be performed by BS 102.

[0317] Method 1400 begins with the BS generating configuration information for channel state information (CSI) calculation and reporting for UE-k, where the configuration includes N ≥ 1 CSI report settings, M ≥ 1 reference signal (RS) settings, and measurement settings (step 1401).

[0318] The measurement setup includes a link between CSI report setup and RS setup, where CSI reports associated with the CSI report setup are calculated based on measurements of reference signals (RSs) associated with the RS setup. Thus, the link determines the dependence of CSI measurements and calculations on the RSs associated with the RS setup. The RS setup is configured for channel measurements or interference measurements. The CSI report setup configures the CSI report to be reported in a periodic, aperiodic, or semi-persistent manner. Similarly, the RS setup is associated with CSI-RS, which is configured to be measured in a periodic, aperiodic, or semi-persistent manner. The CSI report setup includes CSI parameter settings for at least a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), or a CSI-RS resource indicator (CRI). Configuration information is received via higher layer signaling. Then, the BS sends CSI configuration information to UE-k (step 1402) and receives a CSI report from UE-k via an uplink (UL) channel (step 1403).

[0319] Although Figure 13 and Figure 14 respectively show examples of methods for receiving configuration information and configuring a UE, various changes can be made to Figure 13 and Figure 14 . For example, although shown as a series of steps, the individual steps in each figure can overlap, occur in parallel, occur in a different order, occur multiple times, or not be performed in one or more embodiments.

[0320] Although the present disclosure has been described using example embodiments, those skilled in the art can suggest or propose various changes and modifications to those skilled in the art. The present disclosure is intended to cover such changes and modifications that fall within the scope of the appended claims.

Claims

1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: Receiving, from a base station (BS), a radio resource control (RRC) message, the RRC message including information about K sounding reference signal (SRS) resource sets and information indicating semi-persistent SRS transmission, where K is the number of SRS resource sets; Receiving, from the BS, a media access control (MAC) control element (CE) indicating a subset of N out of the K SRS resource sets, where K ≥ N; Determining, based on the MAC CE, whether to transmit the SRS; and Transmitting, based on the determination result, the SRS to the BS on the SRS resource.

2. The method according to claim 1, wherein, The MAC CE indicates whether to activate semi-persistent SRS transmission.

3. The method according to claim 1, wherein, The method further comprises: Receiving, from the BS, downlink control information (DCI) for triggering an aperiodic SRS transmission when the RRC message includes information indicating aperiodic SRS transmission.

4. The method according to claim 3, wherein The method further comprises: Determining, based on the DCI, whether to transmit the SRS when the RRC message includes information indicating aperiodic SRS transmission; and Transmitting, based on the determination result, the SRS to the BS on the SRS resource.

5. The method according to claim 1, wherein, The method further comprises: Receiving, from the BS, a transmit beam indicator (TBI) for configuring the SRS resource.

6. A method performed by a base station (BS) in a wireless communication system, the method comprising: Transmitting, to a user equipment (UE), a radio resource control (RRC) message, the RRC message including information about K sounding reference signal (SRS) resource sets and information indicating semi-persistent SRS transmission, where K is the number of SRS resource sets; Transmitting, to the UE, a media access control (MAC) control element (CE) indicating a subset of N out of the K SRS resource sets, where K ≥ N; and Receiving, from the UE, the SRS based on the SRS resource configured by the UE according to the MAC CE, the MAC CE indicating whether to activate semi-persistent SRS transmission.

7. The method according to claim 6, wherein, The method further comprises: Transmitting, to the UE, downlink control information (DCI) for triggering an aperiodic SRS transmission when the RRC message includes information indicating aperiodic SRS transmission.

8. The method according to claim 6, wherein, The method further comprises: Transmitting, to the UE, a transmit beam indicator (TBI) for configuring the SRS resource.

9. A user equipment (UE) in a wireless communication system, the UE comprising: A transceiver; And At least one processor, coupled to the transceiver and configured to: Receive, from a base station (BS), a radio resource control (RRC) message, the RRC message including information about K sounding reference signal (SRS) resource sets and information indicating semi-persistent SRS transmission, where K is the number of SRS resource sets, Receive, from the BS, a media access control (MAC) control element (CE) indicating a subset of N out of the K SRS resource sets, where K ≥ N, Determine, based on the MAC CE, whether to transmit the SRS, and Transmit, based on the determination result, the SRS to the BS on the SRS resource.

10. The UE according to claim 9, wherein, The MAC CE indicates whether to activate semi-persistent SRS transmission.

11. The UE according to claim 9, wherein, The at least one processor is further configured to: In the case where the RRC message includes information indicating an aperiodic SRS transmission, receive downlink control information DCI from the BS for triggering the aperiodic SRS transmission.

12. The UE according to claim 11, wherein, The at least one processor is further configured to: In the case where the RRC message includes information indicating an aperiodic SRS transmission, determine whether to transmit the SRS based on the DCI, and Transmit the SRS to the BS on the SRS resource based on the determination result.

13. The UE according to claim 11, wherein, The at least one processor is further configured to: Receive a transmit beam indicator TBI for configuring the SRS resource.

14. A base station BS in a wireless communication system, the BS comprising: A transceiver; And At least one processor, coupled to the transceiver and configured to: Transmit a radio resource control RRC message to a user equipment UE, the RRC message including information about K sounding reference signal SRS resource sets and information indicating a semi-persistent SRS transmission, where K is the number of SRS resource sets; Transmit a media access control MAC control element CE indicating a subset of N of the K SRS resource sets to the UE, where K≥N; And Receive the SRS from the UE based on the SRS resource configured by the UE according to the MAC CE, the MAC CE indicating whether to activate the semi-persistent SRS transmission.

15. The BS according to claim 14, wherein The at least one processor is further configured to: In the case where the RRC message includes information indicating an aperiodic SRS transmission, transmit downlink control information DCI for triggering the aperiodic SRS transmission.

16. The BS according to claim 14, wherein The at least one processor is further configured to: Transmit a transmit beam indicator TBI for configuring the SRS resource.

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