Patent Application
20240121065
The present disclosure relates generally to wireless communication systems and, more specifically, to methods and apparatuses for channel state information (CSI) reporting based on a window of basis vectors.
5th generation (5G) or new radio (NR) mobile communications is recently gathering increased momentum with all the worldwide technical activities on the various candidate technologies from industry and academia. The candidate enablers for the 5G/NR mobile communications include massive antenna technologies, from legacy cellular frequency bands up to high frequencies, to provide beamforming gain and support increased capacity, new waveform (e.g., a new radio access technology (RAT)) to flexibly accommodate various services/applications with different requirements, new multiple access schemes to support massive connections, and so on.
This disclosure relates to compression-based CSI reporting.
In one embodiment, a user equipment (UE) is provided. The UE includes a transceiver configured to receive a configuration about a CSI report. The configuration includes information about (i) NTRP non-zero power (NZP) CSI-reference signal (RS) resources, where NTRP≥1, and (ii) a parameter codebookType set to type-II-CJT-r18 or type-II-PortSelection-CJT-r18. The UE further includes a processor operably coupled to the transceiver. The processor, based on the configuration, is configured to determine, for each layer l=1, . . . , v, an indicator i1,8,l for indicating an index (i*l, f*l, r*l) of a strongest coefficient among KlNZ coefficients, where KlNZ is a total number of non-zero coefficients that are associated with Z NZP CSI-RS resources, and Z≤NTRP and a number of bits Pl for the indicator i1,8,l. The transceiver is further configured to transmit the CSI report including, for each layer l=1, . . . , v, Pl bits for the indicator i1,8,l. When codebookType=type-II-CJT-r18, a value of Pl depends on: a value of KlNZ, when v=1, and a value of Σr=1Z Lr, when 1<v≤4. When codebookType=type-II-PortSelection-CJT-r18, the value of Pl depends on a value of 2Mv Σr=1Z Lr for all values of v. Here, v is a total number of layers, Lr is a number of first basis vectors associated with an r-th NZP CSI-RS resource from the Z NZP CSI-RS resources, where r=1, . . . , Z, Mv is a number of second basis vectors, il*∈{0, . . . , 2Lr*
In another embodiment, a base station (BS) is provided. The BS includes a processor and a transceiver operably coupled to the processor. The transceiver is configured to transmit a configuration about a CSI report and receive the CSI report including, for each layer l=1, . . . , v, a number of Pl bits for an indicator i1,8,l. The configuration include information about (i) NTRP NZP CSI-RS resources, where NTRP≥1, and (ii) a parameter codebookType set to type-II-CJT-r18 or type-II-PortSelection-CJT-r18. The indicator i1,8,l is for indicating an index (i*l, f*l, r*l) of a strongest coefficient among KlNZ coefficients, where KlNZ is a total number of non-zero coefficients that are associated with Z NZP CSI-RS resources, and Z≤NTRP. When codebookType=type-II-CJT-r18, a value of Pl depends on: a value of KlNZ, when v=1 and a value of Σr=1Z Lr, when 1<v≤4. When codebookType=type-II-PortSelection-CJT-r18, the value of Pl depends on a value of 2Mv Σr=1Z Lr for all values of v. Here, v is a total number of layers, Lr is a number of first basis vectors associated with an r-th NZP CSI-RS resource from the Z NZP CSI-RS resources, where r=1, . . . , Z, Mv is a number of second basis vectors, i*l∈{0, . . . , 2Lr*
In yet another embodiment, a method performed by a UE is provided. The method includes receiving a configuration about a CSI report. The configuration includes information about (i) NTRP NZP CSI-RS resources, where NTRP≥1, and (ii) a parameter codebookType set to type-II-CJT-r18 or type-II-PortSelection-CJT-r18. The method further includes determining, based on the configuration, for each layer l=1, . . . , v, an indicator i1,8,l for indicating an index (i*l, f*l, r*l) of a strongest coefficient among KlNZ coefficients, where KlNZ is a total number of non-zero coefficients that are associated with Z NZP CSI-RS resources, and Z≤NTRP and a number of bits Pl for the indicator i1,8,l. The method further includes transmitting the CSI report including, for each layer l, Pl bits for the indicator i1,8,l. When codebookType=type-II-CJT-r18, a value of Pl depends on a value of KlNZ, when v=1 and a value of Σr=1Z Lr, when 1<v≤4. When codebookType=type-II-PortSelection-CJT-r18, the value of Pl depends on a value of 2Mv Σr=1Z Lr for all values of v. Here, v is a total number of layers, Lr is a number of first basis vectors associated with an r-th NZP CSI-RS resource from the Z NZP CSI-RS resources, where r=1, . . . , Z, Mv is a number of second basis vectors, i*l∈{0, . . . , 2Lr*
Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.
Before undertaking the DETAILED DESCRIPTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term “couple” 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 one another. The terms “transmit,” “receive,” and “communicate,” as well as derivatives thereof, encompass both direct and indirect communication. The terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive, meaning and/or. The phrase “associated with,” as well as derivatives thereof, means to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The term “controller” means any device, system or part thereof that controls at least one operation. Such a controller may be implemented in hardware or a combination of hardware and software and/or firmware. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. The phrase “at least one of,” when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item in the list may be needed. 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.
Moreover, 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, sets of instructions, procedures, functions, objects, classes, instances, related data, or a portion 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 capable of being accessed by a computer, such as read only memory (ROM), random access memory (RAM), a hard disk drive, a compact disc (CD), a digital video disc (DVD), or any other type of memory. A “non-transitory” computer readable medium excludes wired, wireless, optical, or other communication links that transport transitory electrical or other signals. A non-transitory computer readable medium includes media where data can be permanently stored and media where data can be stored and later overwritten, such as a rewritable optical disc or an erasable memory device.
Definitions for other certain 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 prior as well as future uses of such defined words and phrases.
For a more complete understanding of 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:
The following documents and standards descriptions are hereby incorporated by reference into the present disclosure as if fully set forth herein: 3GPP TS 36.211 v17.0.0, “E-UTRA, Physical Channels and Modulation” (herein “REF 1”); 3GPP TS 36.212 v17.0.0, “E-UTRA, Multiplexing and Channel Coding” (herein “REF 2”); 3GPP TS 36.213 v17.0.0, “E-UTRA, Physical Layer Procedures” (herein “REF 3”); 3GPP TS 36.321 v17.0.0, “E-UTRA, Medium Access Control (MAC) Protocol Specification” (herein “REF 4”); 3GPP TS 36.331 v17.0.0, “E-UTRA, Radio Resource Control (RRC) Protocol Specification” (herein “REF 5”); 3GPP TR 22.891 v1.2.0 (herein “REF 6”); 3GPP TS 38.212 v17.0.0, “E-UTRA, NR, Multiplexing and Channel Coding” (herein “REF 7”); 3GPP TS 38.214 v17.0.0, “E-UTRA, NR, Physical Layer Procedures for Data” (herein “REF 8”); RP-192978, “Measurement Results on Doppler Spectrum for Various UE Mobility Environments and Related CSI Enhancements,” Fraunhofer IIS, Fraunhofer HHI, Deutsche Telekom (herein “REF 9”); and 3GPP TS 38.211 v17.0.0, “E-UTRA, NR, Physical Channels and Modulation” (herein “REF 10”).
Wireless communication has been one of the most successful innovations in modern history. Recently, the number of subscribers to wireless communication services exceeded five billion and continues to grow quickly. The demand of wireless data traffic is rapidly increasing due to the growing popularity among consumers and businesses of smart phones and other mobile data devices, such as tablets, “note pad” computers, net books, eBook readers, and machine type of devices. In order to meet the high growth in mobile data traffic and support new applications and deployments, improvements in radio interface efficiency and coverage is of paramount importance.
To meet the demand for wireless data traffic having increased since deployment of 4G communication systems and to enable various vertical applications, 5G/NR communication systems have been developed and are currently being deployed. The 5G/NR communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 28 GHz or 60 GHz bands, so as to accomplish higher data rates or in lower frequency bands, such as 6 GHz, to enable robust coverage and mobility support. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G/NR communication systems.
In addition, in 5G/NR communication systems, development for system network improvement is under way based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, coordinated multi-points (CoMP), reception-end interference cancelation and the like.
The discussion of 5G systems and frequency bands associated therewith is for reference as certain embodiments of the present disclosure may be implemented in 5G systems. However, the present disclosure is not limited to 5G systems, or the frequency bands associated therewith, and embodiments of the present disclosure may be utilized in connection with any frequency band. For example, aspects of the present disclosure may also be applied to deployment of 5G communication systems, 6G or even later releases which may use terahertz (THz) bands.
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The gNB 102 provides wireless broadband access to the network 130 for a first plurality of user equipments (UEs) within a coverage area 120 of the gNB 102. The first plurality of UEs includes a UE 111, which may be located in a small business; a UE 112, which may be located in an enterprise; a UE 113, which may be a WiFi hotspot; a UE 114, which may be located in a first residence; a UE 115, which may be located in a second residence; and a UE 116, which may be a mobile device, such as a cell phone, a wireless laptop, a wireless PDA, or the like. The gNB 103 provides wireless broadband access to the network 130 for a second plurality of UEs within a coverage area 125 of the gNB 103. The second plurality of UEs includes the UE 115 and the UE 116. In some embodiments, one or more of the gNBs 101-103 may communicate with each other and with the UEs 111-116 using 5G/NR, long term evolution (LTE), long term evolution-advanced (LTE-A), WiMAX, WiFi, or other wireless communication techniques.
Depending on the network type, the term “base station” or “BS” can refer to any component (or collection of components) configured to provide wireless access to a network, such as transmit point (TP), transmit-receive point (TRP), an enhanced base station (eNodeB or eNB), a 5G/NR base station (gNB), a macrocell, a femtocell, a WiFi access point (AP), or other wirelessly enabled devices. Base stations may provide wireless access in accordance with one or more wireless communication protocols, e.g., 5G/NR 3rd generation partnership project (3GPP) NR, long term evolution (LTE), LTE advanced (LTE-A), high speed packet access (HSPA), Wi-Fi 802.11a/b/g/n/ac, etc. For the sake of convenience, the terms “BS” and “TRP” are used interchangeably in this patent document to refer to network infrastructure components that provide wireless access to remote terminals. Also, depending on the network type, the term “user equipment” or “UE” can refer to any component such as “mobile station,” “subscriber station,” “remote terminal,” “wireless terminal,” “receive point,” or “user device.” For the sake of convenience, the terms “user equipment” and “UE” are used in this patent document to refer to remote wireless equipment that wirelessly accesses a BS, whether the UE is a mobile device (such as a mobile telephone or smartphone) or is normally considered a stationary device (such as a desktop computer or vending machine).
Dotted lines show the approximate extents of the coverage areas 120 and 125, which are shown as approximately circular for the purposes of illustration and explanation only. It should be clearly understood that the coverage areas associated with gNBs, such as the coverage areas 120 and 125, may have other shapes, including irregular shapes, depending upon the configuration of the gNBs and variations in the radio environment associated with natural and man-made obstructions.
As described in more detail below, one or more of the UEs 111-116 include circuitry, programing, or a combination thereof preforming CSI reporting based on a window of basis vectors. In certain embodiments, one or more of the BSs 101-103 include circuitry, programing, or a combination thereof for supporting CSI reporting based on a window of basis vectors.
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The transceivers 210a-210n receive, from the antennas 205a-205n, incoming RF signals, such as signals transmitted by UEs in the network 100. The transceivers 210a-210n down-convert the incoming RF signals to generate IF or baseband signals. The IF or baseband signals are processed by receive (RX) processing circuitry in the transceivers 210a-210n and/or controller/processor 225, which generates processed baseband signals by filtering, decoding, and/or digitizing the baseband or IF signals. The controller/processor 225 may further process the baseband signals.
Transmit (TX) processing circuitry in the transceivers 210a-210n and/or controller/processor 225 receives analog or digital data (such as voice data, web data, e-mail, or interactive video game data) from the controller/processor 225. The TX processing circuitry encodes, multiplexes, and/or digitizes the outgoing baseband data to generate processed baseband or IF signals. The transceivers 210a-210n up-converts the baseband or IF signals to RF signals that are transmitted via the antennas 205a-205n.
The controller/processor 225 can include one or more processors or other processing devices that control the overall operation of the gNB 102. For example, the controller/processor 225 could control the reception of UL channel signals and the transmission of DL channel signals by the transceivers 210a-210n in accordance with well-known principles. The controller/processor 225 could support additional functions as well, such as more advanced wireless communication functions. For instance, the controller/processor 225 could support beam forming or directional routing operations in which outgoing/incoming signals from/to multiple antennas 205a-205n are weighted differently to effectively steer the outgoing signals in a desired direction. Any of a wide variety of other functions could be supported in the gNB 102 by the controller/processor 225.
The controller/processor 225 is also capable of executing programs and other processes resident in the memory 230, such as processes to support CSI reporting based on a window of basis vectors in accordance with various embodiment of the present disclosure. The controller/processor 225 can move data into or out of the memory 230 as required by an executing process.
The controller/processor 225 is also coupled to the backhaul or network interface 235. The backhaul or network interface 235 allows the gNB 102 to communicate with other devices or systems over a backhaul connection or over a network. The interface 235 could support communications over any suitable wired or wireless connection(s). For example, when the gNB 102 is implemented as part of a cellular communication system (such as one supporting 5G/NR, LTE, or LTE-A), the interface 235 could allow the gNB 102 to communicate with other gNBs over a wired or wireless backhaul connection. When the gNB 102 is implemented as an access point, the interface 235 could allow the gNB 102 to communicate over a wired or wireless local area network or over a wired or wireless connection to a larger network (such as the Internet). The interface 235 includes any suitable structure supporting communications over a wired or wireless connection, such as an Ethernet or transceiver.
The memory 230 is coupled to the controller/processor 225. Part of the memory 230 could include a RAM, and another part of the memory 230 could include a Flash memory or other ROM.
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The transceiver(s) 310 receives, from the antenna 305, an incoming RF signal transmitted by a gNB of the network 100. The transceiver(s) 310 down-converts the incoming RF signal to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is processed by RX processing circuitry in the transceiver(s) 310 and/or processor 340, which generates a processed baseband signal by filtering, decoding, and/or digitizing the baseband or IF signal. The RX processing circuitry sends the processed baseband signal to the speaker 330 (such as for voice data) or is processed by the processor 340 (such as for web browsing data).
TX processing circuitry in the transceiver(s) 310 and/or processor 340 receives analog or digital voice data from the microphone 320 or other outgoing baseband data (such as web data, e-mail, or interactive video game data) from the processor 340. The TX processing circuitry encodes, multiplexes, and/or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The transceiver(s) 310 up-converts the baseband or IF signal to an RF signal that is transmitted via the antenna(s) 305.
The processor 340 can include one or more processors or other processing devices and execute the OS 361 stored in the memory 360 in order to control the overall operation of the UE 116. For example, the processor 340 could control the reception of DL channel signals and the transmission of UL channel signals by the transceiver(s) 310 in accordance with well-known principles. In some embodiments, the processor 340 includes at least one microprocessor or microcontroller.
The processor 340 is also capable of executing other processes and programs resident in the memory 360. For example, the processor 340 may execute processes for CSI reporting based on a window of basis vectors as described in embodiments of the present disclosure. The processor 340 can move data into or out of the memory 360 as required by an executing process. In some embodiments, the processor 340 is configured to execute the applications 362 based on the OS 361 or in response to signals received from gNBs or an operator. The processor 340 is also coupled to the I/O interface 345, which 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 the communication path between these accessories and the processor 340.
The processor 340 is also coupled to the input 350, which includes for example, a touchscreen, keypad, etc., and the display 355. The operator of the UE 116 can use the input 350 to enter data into the UE 116. The display 355 may be a liquid crystal display, light emitting diode display, or other display capable of rendering text and/or at least limited graphics, such as from web sites.
The memory 360 is coupled to the processor 340. Part of the memory 360 could include a random-access memory (RAM), and another part of the memory 360 could include a Flash memory or other read-only memory (ROM).
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A transmitted RF signal from the gNB 102 arrives at the UE 116 after passing through the wireless channel, and reverse operations to those at the gNB 102 are performed at the UE 116.
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Each of the gNB s 101-103 may implement a transmit path 400 as illustrated in
Each of the components in
Furthermore, although described as using FFT and IFFT, this is by way of illustration only and may not be construed to limit the scope of this disclosure. Other types of transforms, such as discrete Fourier transform (DFT) and inverse discrete Fourier transform (IDFT) functions, can be used. It may be appreciated that the value of the variable N may be any integer number (such as 1, 2, 3, 4, or the like) for DFT and IDFT functions, while the value of the variable N may be any integer number that is a power of two (such as 1, 2, 4, 8, 16, or the like) for FFT and IFFT functions.
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A communication system includes a downlink (DL) that conveys signals from transmission points such as base stations (BSs) or NodeBs to user equipments (UEs) and an uplink (UL) that conveys signals from UEs to reception points such as NodeBs. A UE, also commonly referred to as a terminal or a mobile station, may be fixed or mobile and may be a cellular phone, a personal computer device, or an automated device. An eNodeB, which is generally a fixed station, may also be referred to as an access point or other equivalent terminology. For LTE systems, a NodeB is often referred to as an eNodeB.
In a communication system, such as LTE, DL signals can include data signals conveying information content, control signals conveying DL control information (DCI), and reference signals (RS) that are also known as pilot signals. An eNodeB transmits data information through a physical DL Shared channel (PDSCH). An eNodeB transmits DCI through a physical DL control channel (PDCCH) or an enhanced PDCCH (EPDCCH)—see also REF 3. An eNodeB transmits acknowledgement information in response to data transport block (TB) transmission from a UE in a physical hybrid ARQ indicator channel (PHICH). An eNodeB transmits one or more of multiple types of RS including a UE-common RS (CRS), a channel state information RS (CSI-RS), or a demodulation RS (DMRS). A CRS is transmitted over a DL system bandwidth (BW) and can be used by UEs to obtain a channel estimate to demodulate data or control information or to perform measurements. To reduce CRS overhead, an eNodeB may transmit a CSI-RS with a smaller density in the time and/or frequency domain than a CRS. DMRS can be transmitted only in the BW of a respective PDSCH or EPDCCH and a UE can use the DMRS to demodulate data or control information in a PDSCH or an EPDCCH, respectively. A transmission time interval for DL channels is referred to as a subframe (or slot) and can have, for example, duration of 1 millisecond.
DL signals also include transmission of a logical channel that carries system control information. A BCCH is mapped to either a transport channel referred to as a broadcast channel (BCH) when it conveys a master information block (MIB) or to a DL shared channel (DL-SCH) when it conveys a system information block (SIB)—see also REF 3 and REF 5. Most system information is included in different SIB s that are transmitted using DL-SCH. A presence of system information on a DL-SCH in a subframe (or slot) can be indicated by a transmission of a corresponding PDCCH conveying a codeword with a CRC scrambled with a special system information RNTI (SI-RNTI). Alternatively, scheduling information for a SIB transmission can be provided in an earlier SIB and scheduling information for the first SIB (SIB-1) can be provided by the MIB.
DL resource allocation is performed in a unit of subframe and a group of physical resource blocks (PRBs). A transmission BW includes frequency resource units referred to as resource blocks (RBs). Each RB includes NscRB sub-carriers, or resource elements (REs), such as 12 REs. A unit of one RB over one subframe is referred to as a PRB. A UE can be allocated MPDSCH RBs for a total of MscPDSCH=MPDSCH·NscRB REs for the PDSCH transmission BW.
UL signals can include data signals conveying data information, control signals conveying UL control information (UCI), and UL RS. UL RS includes DMRS and sounding RS (SRS). A UE transmits DMRS only in a BW of a respective PUSCH or PUCCH. An eNodeB can use a DMRS to demodulate data signals or UCI signals. A UE transmits SRS to provide an eNodeB with an UL CSI. A UE transmits data information or UCI through a respective physical UL shared channel (PUSCH) or a physical UL control channel (PUCCH). If a UE needs to transmit data information and UCI in a same UL subframe, the UE may multiplex both in a PUSCH. UCI includes hybrid automatic repeat request acknowledgement (HARQ-ACK) information, indicating correct (ACK) or incorrect (NACK) detection for a data TB in a PDSCH or absence of a PDCCH detection (DTX), scheduling request (SR) indicating whether a UE has data in the UE's buffer, rank indicator (RI), and channel state information (CSI) enabling an eNodeB to perform link adaptation for PDSCH transmissions to a UE. HARQ-ACK information is also transmitted by a UE in response to a detection of a PDCCH/EPDCCH indicating a release of semi-persistently scheduled PDSCH (see also REF 3).
An UL subframe (or slot) includes two slots. Each slot includes NsymbUL symbols for transmitting data information, UCI, DMRS, or SRS. A frequency resource unit of an UL system BW is an RB. A UE is allocated NRB RBs for a total of NRB·NscRB REs for a transmission BW. For a PUCCH, NRB=1. A last subframe symbol can be used to multiplex SRS transmissions from one or more UEs. A number of subframe symbols that are available for data/UCI/DMRS transmission is Nsymb=2·(NsymbUL−1)−NSRS, where NSRS=1 if a last subframe symbol is used to transmit SRS and NSRS=0 otherwise.
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In next generation cellular systems, various use cases are envisioned beyond the capabilities of LTE system. Termed 5G or the fifth-generation cellular system, a system capable of operating at sub-6 GHz and above-6 GHz (for example, in mmWave regime) becomes one of the requirements. In 3GPP TR 22.891, 74 5G use cases have been identified and described; those use cases can be roughly categorized into three different groups. A first group is termed “enhanced mobile broadband (eMBB),” targeted to high data rate services with less stringent latency and reliability requirements. A second group is termed “ultra-reliable and low latency (URLL)” targeted for applications with less stringent data rate requirements, but less tolerant to latency. A third group is termed “massive MTC (mMTC)” targeted for large number of low-power device connections such as 1 million per km2 with less stringent the reliability, data rate, and latency requirements.
The 3GPP NR specification supports up to 32 CSI-RS antenna ports which enable a gNB to be equipped with a large number of antenna elements (such as 64 or 128). In this case, a plurality of antenna elements is mapped onto one CSI-RS port. For next generation cellular systems such as 5G, the maximum number of CSI-RS ports can either remain the same or increase.
For mmWave bands, although the number of antenna elements can be larger for a given form factor, the number of CSI-RS ports—which can correspond to the number of digitally precoded ports—tends to be limited due to hardware constraints (such as the feasibility to install a large number of ADCs/DACs at mmWave frequencies) as illustrated in
To enable digital precoding, efficient design of CSI-RS is a crucial factor. For this reason, three types of CSI reporting mechanism corresponding to three types of CSI-RS measurement can be considered: 1) ‘CLASS A’ CSI reporting which corresponds to non-precoded CSI-RS, 2) ‘CLASS B’ reporting with K=1 CSI-RS resource which corresponds to UE-specific beamformed CSI-RS, 3) ‘CLASS B’ reporting with K>1 CSI-RS resources which corresponds to cell-specific beamformed CSI-RS. For non-precoded (NP) CSI-RS, a cell-specific one-to-one mapping between CSI-RS port and TXRU is utilized. Here, different CSI-RS ports have the same wide beam width and direction and hence generally cell wide coverage. For beamformed CSI-RS, beamforming operation, either cell-specific or UE-specific, is applied on a non-zero-power (NZP) CSI-RS resource (including multiple ports). Here, (at least at a given time/frequency) CSI-RS ports have narrow beam widths and hence not cell wide coverage, and (at least from the eNB (or gNB) perspective) at least some CSI-RS port-resource combinations have different beam directions.
In scenarios where DL long-term channel statistics can be measured through UL signals at a serving eNodeB, UE-specific BF CSI-RS can be readily used. This is typically feasible when UL-DL duplex distance is sufficiently small. When this condition does not hold, however, some UE feedback is necessary for the eNodeB to obtain an estimate of DL long-term channel statistics (or any of its representation thereof). To facilitate such a procedure, a first BF CSI-RS transmitted with periodicity T1 (ms), and a second NP CSI-RS transmitted with periodicity T2 (ms), where T1≤T2. This approach is termed hybrid CSI-RS. The implementation of hybrid CSI-RS is largely dependent on the definition of CSI process and NZP CSI-RS resource.
In a wireless communication system, MIMO is often identified as an essential feature in order to achieve high system throughput requirements. One of the key components of a MIMO transmission scheme is the accurate CSI acquisition at the eNB (or gNB) (or TRP). For MU-MIMO, in particular, the availability of accurate CSI is necessary in order to guarantee high MU performance. For TDD systems, the CSI can be acquired using the SRS transmission relying on the channel reciprocity. For FDD systems, on the other hand, it can be acquired using the CSI-RS transmission from eNB (or gNB), and CSI acquisition and feedback from UE. In legacy FDD systems, the CSI feedback framework is “implicit” in the form of CQI/PMI/RI (also CRI and LI) derived from a codebook assuming SU transmission from eNB (or gNB).
In 5G or NR systems (REF 7, REF 8), the above-mentioned “implicit” CSI reporting paradigm from LTE is also supported and referred to as Type I CSI reporting. In addition, a high-resolution CSI reporting, referred to as Type II CSI reporting, is also supported in Release 15 specification to provide more accurate CSI information to gNB for use cases such as high-order MU-MIMO. However, the overhead of Type II CSI reporting can be an issue in practical UE implementations. One approach to reduce Type II CSI overhead is based on frequency domain (FD) compression. In Rel. 16 NR, DFT-based FD compression of the Type II CSI has been supported (referred to as Rel. 16 enhanced Type II codebook in REF 8). Some of the key components for this feature includes (a) spatial domain (SD) basis W1, (b) FD basis Wf, and (c) coefficients {tilde over (W)}2 that linearly combine SD and FD basis. In a non-reciprocal FDD system, a complete CSI (comprising all components) needs to be reported by the UE. However, when reciprocity or partial reciprocity does exist between UL and DL, then some of the CSI components can be obtained based on the UL channel estimated using SRS transmission from the UE. In Rel. 16 NR, the DFT-based FD compression is extended to this partial reciprocity case (referred to as Rel. 16 enhanced Type II port selection codebook in REF 8), wherein the DFT-based SD basis in W1 is replaced with SD CSI-RS port selection, i.e., L out of PCSI-RS/2 CSI-RS ports are selected (the selection is common for the two antenna polarizations or two halves of the CSI-RS ports). The CSI-RS ports in this case are beamformed in SD (assuming UL-DL channel reciprocity in angular domain), and the beamforming information can be obtained at the gNB based on UL channel estimated using SRS measurements.
In Rel. 17 NR, CSI reporting has been enhanced to support the following.
In Rel. 18 MIMO WID includes the following objectives on CSI enhancements:
The first objective extends the Rel. 17 NCJT CSI to coherent JT (CJT), and the second extends FD compression in the Rel. 16/17 codebook to include time (Doppler) domain compression. Both extensions are based on the same legacy codebook, i.e., Rel. 16/17 codebook. In this disclosure, a unified codebook design considering both extensions has been proposed.
As illustrated in
The multiple RRHs/TRPs in a D-MIMO setup can be utilized for spatial multiplexing gain (based on CSI reporting). Since RRHs/TRPs are geographically separated, they (RRHs/TRPs) tend to contribute differently in CSI reporting. This motivates a dynamic RRH selection followed by CSI reporting condition on the RRH selection. This disclosure provides example embodiments on how channel and interference signal can be measure under different RRH selection hypotheses. Additionally, the signaling details of such a CSI reporting and CSI-RS measurement are also provided.
Various embodiments of the present disclosure that relate to time-/Doppler-domain compression are moderate to high mobility embodiments. Some embodiments recognize that when the UE speed is in a moderate or high-speed regime, the performance of the Rel. 15/16/17 codebooks starts to deteriorate quickly due to fast channel variations (which in turn is due to UE mobility that contributes to the Doppler component of the channel), and a one-shot nature of CSI-RS measurement and CSI reporting in Rel. 15/16/17. This limits the usefulness of Rel. 15/16/17 codebooks to low mobility or static UEs only. For moderate or high mobility scenarios, an enhancement in CSI-RS measurement and CSI reporting is needed, which is based on the time-domain (TD) variations or Doppler components of the channel. As described in (REF 9), the Doppler components of the channel remain almost constant over a large time duration, referred to as channel stationarity time, which is significantly larger than the channel coherence time. Note that the current (Rel. 15/16/17) CSI reporting is based on the channel coherence time, which is not suitable when the channel has significant Doppler components. The Doppler components of the channel can be calculated based on measuring a reference signal (RS) burst, where the RS can be CSI-RS or SRS. When RS is CSI-RS, the UE measures a CSI-RS burst, and use it to obtain Doppler components of the DL channel, and when RS is SRS, the gNB measures an SRS burst, and use it to obtain Doppler components of the UL channel. The obtained Doppler components can be reported by the UE using a codebook (as part of a CS report). Or, the gNB can use the obtained Doppler components of the UL channel to beamform CSI-RS for CSI reporting by the UE.
An illustration of channel measurement with and without Doppler components is shown in
Various embodiments of the present disclosure provide mechanisms for CSI acquisition at gNB. In particular, various embodiments relate to the CSI reporting based on a high-resolution (or Type II) codebook comprising spatial-, frequency- or/and time- (Doppler-) domain components for a distributed antenna structure (DMIMO). Various embodiments of the present disclosure provide mechanisms for selection of frequency domain basis vectors for multiple TRPs from a window where the window can be one/common across TRPs, or one per TRP, details of window(s): initial index (Minit) and length W, signaling: configured window, reported window, and for multiple windows: a reference window+a relative offset per TRP w.r.t. to the reference window, and details on SCI.
All the following components and embodiments are applicable for UL transmission with CP-OFDM (cyclic prefix OFDM) waveform as well as DFT-SOFDM (DFT-spread OFDM) and SC-FDMA (single-carrier FDMA) waveforms. Furthermore, all the following components and embodiments are applicable for UL transmission when the scheduling unit in time is either one subframe (which can include of one or multiple slots) or one slot.
In the present disclosure, the frequency resolution (reporting granularity) and span (reporting bandwidth) of CSI reporting can be defined in terms of frequency “subbands” and “CSI reporting band” (CRB), respectively.
A subband for CSI reporting is defined as a set of contiguous PRBs which represents the smallest frequency unit for CSI reporting. The number of PRBs in a subband can be fixed for a given value of DL system bandwidth, configured either semi-statically via higher-layer/RRC signaling, or dynamically via L1 DL control signaling or MAC control element (MAC CE). The number of PRBs in a subband can be included in CSI reporting setting.
“CSI reporting band” is defined as a set/collection of subbands, either contiguous or non-contiguous, wherein CSI reporting is performed. For example, CSI reporting band can include all the subbands within the DL system bandwidth. This can also be termed “full-band”. Alternatively, CSI reporting band can include only a collection of subbands within the DL system bandwidth. This can also be termed “partial band”.
The term “CSI reporting band” is used only as an example for representing a function. Other terms such as “CSI reporting subband set” or “CSI reporting bandwidth” or bandwidth part (BWP) can also be used.
In terms of UE configuration, a UE can be configured with at least one CSI reporting band. This configuration can be semi-static (via higher-layer signaling or RRC) or dynamic (via MAC CE or L1 DL control signaling). When configured with multiple (N) CSI reporting bands (e.g., via RRC signaling), a UE can report CSI associated with n≤N CSI reporting bands. For instance, >6 GHz, large system bandwidth may require multiple CSI reporting bands. The value of n can either be configured semi-statically (via higher-layer signaling or RRC) or dynamically (via MAC CE or L1 DL control signaling). Alternatively, the UE can report a recommended value of n via an UL channel.
Therefore, CSI parameter frequency granularity can be defined per CSI reporting band as follows. A CSI parameter is configured with “single” reporting for the CSI reporting band with Mn subbands when one CSI parameter for all the Mn subbands within the CSI reporting band. A CSI parameter is configured with “subband” for the CSI reporting band with Mn subbands when one CSI parameter is reported for each of the Mn subbands within the CSI reporting band.
As illustrated in
comprise a first antenna polarization, and antenna ports
comprise a second antenna polarization, where PCSIRS is a number of CSI-RS antenna ports and X is a starting antenna port number (e.g., X=3000, then antenna ports are 3000, 3001, 3002, . . . ). Let Ng be a number of antenna panels at the gNB. When there are multiple antenna panels (Ng>1), each panel may be dual-polarized antenna ports with N1 and N2 ports in two dimensions. This is illustrated in
In one example, the antenna architecture of a D-MIMO or CJT system is structured. For example, the antenna structure at each RRH (or TRP) is dual-polarized (single or multi-panel as shown in
In another example, the antenna architecture of a D-MIMO or CJT system is unstructured. For example, the antenna structure at one RRH/TRP can be different from another RRH/TRP.
For various embodiments, a structured antenna architecture may be assumed in the rest of the disclosure. Furthermore, for simplicity, it may be assumed that each RRH/TRP is equivalent to a panel (cf.
In one embodiment, an RRH constitutes (or corresponds to or is equivalent to) at least one of the following:
In one example, when RRH/TRP maps (or corresponds to) a CSI-RS resource or resource group, and a UE can select a subset of RRHs/TRPs (resources or resource groups) and report the CSI for the selected RRHs/TRPs (resources or resource groups), the selected RRHs/TRPs can be reported via an indicator. For example, the indicator can be a CRI or a PMI (component) or a new indicator.
In one example, when RRH maps (or corresponds to) a CSI-RS port, and a UE can select a subset of RRHs/TRPs (port groups) and report the CSI for the selected RRHs/TRPs (port groups), the selected RRHs/TRPs can be reported via an indicator. For example, the indicator can be a CRI or a PMI (component) or a new indicator.
In one example, when multiple (K>1) CSI-RS resources are configured for NRRH RRHs/TRPs, a decoupled (modular) codebook is used/configured, and when a single (K=1) CSI-RS resource for NRRH RRHs/TRPs, a joint codebook is used/configured.
As described in U.S. Pat. No. 10,659,118, issued May 19, 2020, and entitled “Method and Apparatus for Explicit CSI Reporting in Advanced Wireless Communication Systems,” which is incorporated herein by reference in its entirety, a UE is configured with high-resolution (e.g., Type II) CSI reporting in which the linear combination-based Type II CSI reporting framework is extended to include a frequency dimension in addition to the first and second antenna port dimensions.
As illustrated,
The basis sets for 1st and 2nd port domain representation are oversampled DFT codebooks of length-N1 and length-N2, respectively, and with oversampling factors O1 and O2, respectively. Likewise, the basis set for frequency domain representation (i.e., 3rd dimension) is an oversampled DFT codebook of length-N3 and with oversampling factor O3. In one example, O1=O2=O3=4. In one example, O1=O2=4 and O3=1. In another example, the oversampling factors Oi belongs to {2, 4, 8}. In yet another example, at least one of O1, O2, and O3 is higher layer configured (via RRC signaling).
As explained in Section 5.2.2.2.5 of REF 8, a UE is configured with higher layer parameter codebookType set to ‘typeII-r16’ for an enhanced Type II CSI reporting in which the pre-coders for all SBs and for a given layer l=1, . . . , v, where v is the associated RI value, is given by either:
where:
In a variation, when the UE reports a subset K<2LM coefficients (where K is either fixed, configured by the gNB or reported by the UE), then the coefficient cl,i,f in precoder equations Eq. 1 or Eq. 2 is replaced with xl,i,f×cl,i,f where:
The indication whether xl,i,f=1 or 0 is according to some embodiments of this disclosure. For example, it can be via a bitmap.
In a variation, the precoder equations Eq. 1 or Eq. 2 are respectively generalized to:
where for a given i, the number of basis vectors is Mi and the corresponding basis vectors are {bi,f}. Note that Mi is the number of coefficients cl,i,f reported by the UE for a given i, where Mi≤M (where {Mi} or Σ Mi is either fixed, configured by the gNB or reported by the UE).
The columns of Wl are normalized to norm one. For rank R or R layers (v=R), the pre-coding matrix is given by
Eq. 2 is assumed in the rest of the disclosure. The embodiments of the disclosure, however, are general and are also application to Eq. 1, Eq. 3, and Eq. 4.
Here
then A is an identity matrix, and hence not reported. Likewise, if M=N3, then B is an identity matrix, and hence not reported. Assuming M<N3, in an example, to report columns of B, the oversampled DFT codebook is used. For instance, bf=wf, where the quantity wf is given by:
When O3=1, the FD basis vector for layer l∈{1, . . . , v} (where v is the RI or rank value) is given by:
where
and n3,l=[n3,l(0), . . . n3,l(M-1)] where n3,l(f)∈{0, 1, . . . , N3−1}.
In another example, discrete cosine transform DCT basis is used to construct/report basis B for the 3rd dimension. The m-th column of the DCT compression matrix is simply given by:
and K=N3, and m=0, . . . , N3−1.
Since DCT is applied to real valued coefficients, the DCT is applied to the real and imaginary components (of the channel or channel eigenvectors) separately. Alternatively, the DCT is applied to the magnitude and phase components (of the channel or channel eigenvectors) separately. The use of DFT or DCT basis is for illustration purpose only. The disclosure is applicable to any other basis vectors to construct/report A and B.
On a high level, a precoder Wl can be described as follows:
W=A
l
C
l
B
l
H
=W
1
{tilde over (W)}
2
W
f
H, (Eq. 5)
where A=W1 corresponds to the Rel. 15 W1 in Type II CSI codebook (REF 8), and B=Wf.
The Cl={tilde over (W)}2 matrix includes all the required linear combination coefficients (e.g., amplitude and phase or real or imaginary). Each reported coefficient (cl,i,f=pl,i,fϕl,i,f) in {tilde over (W)}2 is quantized as amplitude coefficient (pl,i,f) and phase coefficient (ϕl,i,f). In one example, the amplitude coefficient (pl,i,f) is reported using a A-bit amplitude codebook where A belongs to {2, 3, 4}. If multiple values for A are supported, then one value is configured via higher layer signalling. In another example, the amplitude coefficient (pl,i,f) is reported as pl,i,f=pl,i,f(1)pl,i,f(2) where:
The above-mentioned framework (Eq. 5) represents the precoding-matrices for multiple (N3) FD units using a linear combination (double sum) over 2L SD beams and Mv FD beams. This framework can also be used to represent the precoding-matrices in time domain (TD) by replacing the FD basis matrix Wf with a TD basis matrix Wt, wherein the columns of Wt comprises Mv TD beams that represent some form of delays or channel tap locations. Hence, a precoder Wl can be described as follows:
W=A
l
C
l
B
l
H
=W
1
{tilde over (W)}
2
W
t
H, (Eq. 5A)
In one example, the Mv TD beams (representing delays or channel tap locations) are selected from a set of N3 TD beams, i.e., N3 corresponds to the maximum number of TD units, where each TD unit corresponds to a delay or channel tap location. In one example, a TD beam corresponds to a single delay or channel tap location. In another example, a TD beam corresponds to multiple delays or channel tap locations. In another example, a TD beam corresponds to a combination of multiple delays or channel tap locations.
Various embodiments of the present disclosure are applicable to both space-frequency (Eq. 5) and space-time (Eq. 5A) frameworks.
The abovementioned framework for CSI reporting based on space-frequency compression (Eq. 5) or space-time compression (Eq. 5A) frameworks can be extended in two directions:
As illustrated in
For purposes of the present disclosure, the notation NTRP, NRRH, and K are used interchangeably for the number of NZP CSI-RS resources (configured in one CSI-RS resource set) or number of TRPs/RRHs. Hence, K=NTRP=NRRH.
In one embodiment, a UE is configured with a CSI report for Z≥1 TRPs (across or associated with Z NZP CSI-RS resources) based on a codebook that includes components, SD and FD bases (for compression), similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 38.214) or rel. 17 further enhanced Type II port selection codebook (5.2.2.2.7, 38.214). The value of Z can be equal to NTRP, the number of TRPs or NZP CSI-RS resources configured for the CSI report. Or, the value of 1≤Z≤NTRP, where Z can be reported by the UE (e.g., via the CSI report) or signaled to the UE (e.g., via MACE CE or/and DCI). In one example, NTRP∈{1, 2, 3, 4}. For example, the selection of Z CSI-RS resources can be reported with an NTRP-bit bitmap, bN
For purposes of the present disclosure, the notation N and Z are used interchangeably for the number of selected NZP CSI-RS resources or number of selected TRPs/RRHs for the CSI report. Hence, N=Z.
The precoding matrices indicated by the PMI are determined from Σr=1N Lσ
At least one of the following embodiments is used/configured.
In one embodiment, the UE is configured to report a CSI for N≥1 TRPs/RRHs/TRPs (where TRP corresponds to a NZP CSI-RS resource or a subset of CSI-RS antenna ports within a NZP CSI-RS resource), the CSI determined based on a codebook comprising components: (A) two separate basis matrices W1, Wf for SD and FD compression, respectively, and (B) coefficients {tilde over (W)}2. In one example, the codebook can be configured via one higher layer parameter codebookType set to ‘typeII-cjt-mode2-r18’, or via two higher layer parameters codebookType set to ‘ typeII-cjt-r18’ and codebookMode set to ‘Mode2’.
In particular, the precoder for layer l is given by:
In one example, for each r=1, . . . , N,
is a PCSIRS,r×2Lr SD basis matrix, where the Lr SD basis vectors comprising columns of Br are determined the same way as in Rel. 15/16 Type II codebooks (cf. 5.2.2.2.3, REF 8).
In one example, the Mv FD basis vectors, gf,l=[y0,l(f) y1,l(f) . . . yN
n
3,l
=[n
3,l
(0)
, . . . ,n
3,l
(M
-1)]
n
3,l
(f)∈{0,1, . . . ,N3−1}
The vector yt,l=[yt,l(0) yt,l(1) . . . yt,l(M
In one example, the FD basis vectors are orthogonal DFT vectors, and
In one example, the FD basis vectors are oversampled (or rotated) orthogonal DFT vectors with the oversampling (rotation) factor O3, and
and the Mv FD basis vectors are also identified by the rotation index q3,l∈{0, 1, . . . , O3−1}. In one example, O3 is fixed (e.g., 1 or 4), or configured (e.g., via RRC), or reported by the UE. In one example, the rotation factor is layer-common (one value for all layers), i.e., q3,l=q3.
In one example, each coefficient corresponding to row i, column f of the W2,l,r for layer l and TRP (or CSI-RS resource) r can be expressed as
similar to Rel. 16 enhanced Type II codebook (cf. Section 5.2.2.2.5, REF 8).
In one embodiment, the UE is configured to report a CSI for N≥1 RRHs/TRPs (where TRP corresponds to a NZP CSI-RS resource or a subset of CSI-RS antenna ports within a NZP CSI-RS resource), the CSI determined based on a codebook comprising components: (A) two separate basis matrices W1, Wf for SD and FD compression, respectively, and (B) coefficients {tilde over (W)}2. In one example, the codebook can be configured via one higher layer parameter codebookType set to ‘typeII-cjt-mode1-r18’, or via two higher layer parameters codebookType set to ‘ typeII-cjt-r18’ and codebookMode set to ‘Mode1’.
In particular, the precoder for layer l is given by:
In one example, for each r=1, . . . , N,
is a PCSIRS,r×2Lr SD basis matrix, where the Lr SD basis vectors comprising columns of Br are determined the same way as in Rel. 15/16 Type II codebooks (cf. 5.2.2.2.3, REF 8).
In one example, the Mv,r FD basis vectors, gr,f,l=[y0,l(r,f) y1,l(r,f) . . . yN
n
3,l,r
=[n
3,l,r
(0)
, . . . ,n
3,l,r
(M
-1)]
n
3,l,r
(f)∈{0,1, . . . ,N3−1}
The vector yt,l,r=[yt,l,r(0) yt,l,r(1) . . . yt,l,r(M
In one example, the FD basis vectors are orthogonal DFT vectors, and
In one example, the FD basis vectors are oversampled (or rotated) orthogonal DFT vectors with the oversampling (rotation) factor O3, and
and the Mv,r FD basis vectors are also identified by the rotation index q3,l,r∈{0, 1, . . . , O3−1}. In one example, O3 is fixed (e.g., 1 or 4), or configured (e.g., via RRC), or reported by the UE. In one example, the rotation factor is layer-common (one value for all layers), i.e., q3,l,rq3,r.
In one example, Wf,r=diag(Or)Wf, where
is a phase offset vector with phase offset value ψr. Hence, the subscript r can be dropped (removed) from Mv,r, n3,l,r, y0,l(r,f), n3,l,r(f), and q3,l,r.
In one example, corresponding to row i, column f of the W2,l,r for layer l and TRP (or CSI-RS resource)
similar to Rel. 16 enhanced Type II codebook (cf. Section 5.2.2.2.5, REF 8).
In one embodiment, a UE is configured with a CSI reporting based on a codebook which is one of the two codebooks described in various embodiments disclosed herein. In one example, this configuration can be via a higher layer parameter CodeookMode.
In one embodiment, which may be a variation of other embodiments disclosed herein, wherein the SD basis selection matrix is replaced with a SD port selection matrix. In one example, the codebook in this case can be configured via one higher layer parameter codebookType set to ‘typeII-PortSelection-cjt-mode1-r18’, or via two higher layer parameters codebookType set to ‘typeII-PortSelection-cjt-r18” and codebookMode set to ‘Mode2’.
In one example, vm
In one example, vm
For TRP r, K1,r=2Lr ports are selected from PCSI-RS, r ports based on Lr vectors, vm
which are indicated by the index i1,2=[i1,2,1 . . . i1,2,N], where:
In one embodiment, which may be a variation of other embodiments disclosed herein, wherein the SD basis selection matrix is replaced with a SD port selection matrix. In one example, the codebook in this case can be configured via one higher layer parameter codebookType set to ‘typeII-PortSelection-cjt-mode1-r18’, or via two higher layer parameters codebookType set to ‘typeII-PortSelection-cjt-r18” and codebookMode set to ‘Mode1’.
In one example, vm
In one example, vm
For TRP r, K1,r=2L, ports are selected from PCSI-RS, r ports based on Lr vectors, vm
which are indicated by the index i1,2=[i1,2,1 . . . i1,2,N], where:
In one embodiment, which may be a variation of other embodiments disclosed herein, wherein the SD basis selection matrix is replaced with a SD port selection matrix.
In one example, vm
In one example, vm
For TRP r, K1,r=2L, ports are selected from PCSI-RS, r ports based on Lr vectors, vm
which are indicated by the index i1,2=[i1,2,1 . . . i1,2,N], where:
In one embodiment, a UE is configured with a CSI report for Z≥1 TRPs or CSI-RS resources (from a total of NTRP NZP CSI-RS resources) based on a codebook, where the codebook is configured according to at least one of the embodiments disclosed herein. In addition, the FD basis vectors comprising columns of Wf can be determined/reported according to at least one of the following embodiments.
Let Mv,r be the number of FD basis vectors determined/reported for rank (number of layers) v and TRP (CSI-RS resource) index r∈{1, . . . , Z}.
In one embodiment, a UE can be configured to report M or Mr FD basis vectors in one-step from a total of N3 basis vectors, where the M or Mr FD basis vectors are common for all layers l∈{1, . . . , v} of a rank v CSI reporting. The total of N3 basis vectors correspond to orthogonal DFT basis vectors, each length N3×1.
In one example, as described in embodiment I.1/I.4, one common/joint M FD basis vectors are determined/reported, which is used across all TRPs or CSI-RS resources, and across all layers.
In one example, the M FD basis vectors, gf=[y0(f) y1(f) . . . yN
n
3
[n
3
(0)
, . . . ,n
3
(M-1)]
n
3
(f)∈{0,1, . . . ,N3−1}
which are indicated by means of the index i1,6 (for M>1), where i1,6∈{0, 1, . . . , X−1}. The UE reports i1,6 via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3(0)=0. In one example,
The payload for i1,6 reporting is ┌log2 X┐ bits.
In one example, as described in various embodiments disclosed herein, Mr FD basis vectors are determined/reported for each TRP (CSI-RS resource), and for a TRP, the reported Mr FD basis vectors are same/common for all layers.
In one example, the Mr FD basis vectors, gf,r=[y0,r(f) y1,r(f) . . . yN
n
3,r
=[n
3,r
(0)
, . . . ,n
3,r
(M
-1)]
n
3,r
(f)∈{0,1, . . . N3−1}
which are indicated by means of the indices i1,6,r (for Mr>1), where i1,6,r∈{0, 1, . . . , X−1}. The UE reports i1,6,r (r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,r(0)=0. In one example,
The payload for i1,6,r reporting is ┌log2 X┐ bits.
In one embodiment, a UE can be configured to report Mv or Mv,r FD basis vectors in one-step from a total of N3 basis vectors separately (independently) for each layer l∈{1, . . . , v} of a rank v CSI reporting.
In one example, as described in various embodiments disclosed herein, one common/joint Mv FD basis vectors are determined/reported across all TRPs or CSI-RS resources, and for rank>1, the Mv FD basis vectors are determined/reported independently for each layer l=1, . . . , v.
In one example, the M, FD basis vectors, gf,l=[y0,l(f) y1,l(f) . . . yN
n
3,l
=[n
3,l
(0)
, . . . ,n
3,l
(M
-1)]
n
3,l
(f)∈{0,1, . . . N3−1}
which are indicated by means of the indices i1,6,l (for Mv>1), where i1,6,l∈{0, 1, . . . , X−1}. The UE reports i1,6,l (l=1, . . . , v) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l(0)=0. In one example,
The payload for i1,6,l reporting is ┌log2 X┐ bits.
In one example, as described in various embodiments disclosed herein, for each TRP (CSI-RS resource), Mv,r FD basis vectors are determined/reported independently for each TRP (CSI-RS resource) and for each layer.
In one example, the Mv,r FD basis vectors, gf,l,r=[y0,l,r(f) y1,l,r(f) . . . yN
which are indicated by means of the indices i1,6,l,r (for Mv,r>1), where i1,6,l,r∈{0, 1, . . . , X−1}. The UE reports i1,6,l,r (l=1, . . . , v and r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l,r(0)=0. In one example,
The payload for i1,6,l,r reporting is ┌log2 X┐ bits.
In one embodiment, a UE can be configured to report M or Mr FD basis vectors from a set/window of NM FD basis vectors, where the M or Mr FD basis vectors are common for all layers l∈{1, . . . , v} of a rank v CSI reporting, and the set/window is a subset of a total of N3 basis vectors. In one example, NM≤N3. In one example, NM<N3. The total of N3 basis vectors correspond to orthogonal DFT basis vectors, each length N3×1.
The indices of the FD basis vectors in the set/window are given by mod(Minit+n, N3), n=0, 1, . . . , NM−1, which comprises NM adjacent FD basis indices with modulo-shift by N3, where Minit is the starting index of the window. An example 1600 is shown in
For Z>1 TRPs (CSI-RS resources), Minit can be fixed to (or configured with or reported) as the same/common value for all TRPs, or Minit can be fixed to (or configured with or reported) same or different values across TRPs. Likewise, for Z>1 TRPs (CSI-RS resources), NM can be fixed to (or configured with or reported) the same/common value for all TRPs, or NM can be fixed to (or configured with or reported) same or different values across TRPs.
In one example, as described in various embodiments disclosed herein, one common/joint M FD basis vectors are determined/reported, which is used across all TRPs or CSI-RS resources, and across all layers.
In one example, when Minit is fixed, it can be fixed, for example, to Minit=0, in which case the window is given by the set of FD indices {n=0, 1, . . . , W−1}, where W=NM or W=min(NM, N3) or W=NM=aM where a can be fixed, e.g., a=2. The M FD basis vectors, gf=[y0(f) y1(f) . . . yN
n
3
=[n
3
(0)
, . . . ,n
3
(M-1)]
n
3
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the index i1,6 (for M>1), where i1,6∈{0, 1, . . . , X−1}. The UE reports i1,6 via the PMI included in the CSI report. In one example
when one of the FD basis vectors is fixed, e.g., n3(0)=0. In one example,
The payload for i1,6 reporting is ┌log2 X┐ bits.
In one example, when Minit is reported, it can be reported via an indicator iinit or i1,5, which can be given by:
In one example, W=NM=aM where a can be fixed, e.g., a=2. In one example, N is configured. In one example, W=min(N, N3). The M FD basis vectors, gf=[y0(f) y1(f) . . . yN
M
init
∈{−W+1,−W+2, . . . ,0}
n
3
=[n
3
(0)
, . . . ,n
3
(M-1)]
n
3
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the indices i1,5 and i1,6 (for M>1), where i1,5∈{0, 1, . . . , W−1} and i1,6∈{0, 1, . . . , X−1}. The UE reports i1,5 and i1,6 via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3(0)=0. In one example,
The payload for i1,6 reporting is ┌log2 X┐ bits. The payload for i1,5 reporting is ┌log2 W┐ bits.
In one example, as described in various embodiments disclosed herein, Mr FD basis vectors are determined/reported for each TRP (CSI-RS resource), and for a TRP, the reported Mr FD basis vectors are same/common for all layers.
In one example, the window for FD basis vector reporting is common/same across TRPs (CSI-RS resources) and Minit is fixed. When Minit is fixed, it can be fixed, for example, to Minit=0, in which case the window is given by the set of FD indices {n=0, 1, . . . , W−1}, where W=NM or W=min(NM, N3) or W=NM=aM where a can be fixed, e.g., a=2. The Mr FD basis vectors, gf,r=[y0,r(f) y1,r(f) . . . yN
n
3,r
=[n
3,r
(0)
, . . . ,n
3,r
(M
-1)]
n
3,r
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the indices i1,6,r (for Mr>1), where i1,6,r∈{0, 1, . . . , X−1}. The UE reports i1,6,r (r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,r(0)=0. In one example,
The payload for i1,6,r reporting is ┌log2 X┐ bits.
In one example, the window for FD basis vector reporting is common/same across TRPs (CSI-RS resources) and Minit is reported. When Minit is reported, it can be reported via an indicator iinit or i1,5, which can be given by:
In one example, W=NM=aM where a can be fixed, e.g., a=2. In one example, NM is configured. In one example, W=min(N m, N3). Mr FD basis vectors, gf,r=[y0,r(f) y1,r(f) . . . yN
M
init
∈{−W+1,−W+2, . . . ,0}
n
3,r
=[n
3,r
(0)
, . . . ,n
3,r
(M
-1)]
n
3,r
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the indices i1,5 and i1,6,r (for Mr>1), where i1,5∈{0, 1, . . . , W−1} and i1,6,r∈{0, 1, . . . , X−1}. The UE reports i1,5 and i1,6,r (r=1, Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,r(0)=0. In one example,
The payload for i1,6,r reporting is ┌log2 X┐ bits. The payload for i1,5 reporting is ┌log2 W┐ bits.
In one example, the window for FD basis vector reporting is independent/separate across TRPs (CSI-RS resources), i.e., one window for each TRP, and Minit is fixed. When Minit is fixed, it can be fixed, for example, to Minit=0, in which case the window for TRP (CSIRS resource) r is given by the set of FD indices {n=0, 1, . . . , Wr−1}, where Wr=Nr or Wr=min(Nr, N3) or Wr=Nr=aMr where a can be fixed, e.g., a=2. The Mr FD basis vectors, gf,r=[y0,r(f) y1,r(f) . . . yN
n
3,r
=[n
3,r
(0)
, . . . ,n
3,r
(M
-1)]
n
3,r
(f)∈{0,1, . . . ,Wr−1}
which are indicated by means of the indices i1,6,r (for Mr>1), where i1,6,r∈{0, 1, . . . , X−1}. The UE reports i1,6,r (r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,r(0)=0. In one example,
The payload for i1,6,r reporting is ┌log2 X┐ bits. Note Wr can be the same or different for r=1, . . . , Z.
In one example, the window for FD basis vector reporting is independent/separate across TRPs (CSI-RS resources), i.e., one window for each TRP, and Minit is reported. When Minit,r is reported per TRP r, it can be reported via an indicator iinit,r or i1,5,r, which can be given by:
In one example, Wr=Nr=aMr where a can be fixed, e.g., a=2. In one example, Nr is configured. In one example, Wr=min(Nr, N3). Mr FD basis vectors, gf,r=[y0,r(f) y1,r(f) . . . yN
M
init,r
∈{−W
r+1,−Wr+2, . . . ,0}
n
3,r
=[n
3,r
(0)
, . . . ,n
3,r
(M
-1)]
n
3,r
(f)∈{0,1, . . . ,Wr−1}
which are indicated by means of the indices i1,5,r and i1,6,r (for Mr>1), where i1,5,r∈{0, 1, . . . , Wr−1} and i1,6,r∈{0, 1, . . . , X−1}. The UE reports i1,5,r and i1,6,r (r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,r(0)=0. In one example,
The payload for i1,6,r reporting is ┌log2 X┐ bits. The payload for i1,5,r reporting is ┌log2 Wr┐ bits.
In one example, Minit,r=Minit when the same (one) value for Minit is reported for all TRPs, and in this case, it can be reported via an indicator iinit or i1,5. Note Wr can be the same or different for r=1, . . . , Z.
In one example, Minit,r can be the same or different across TRPs, and in this case, Wr can be the same or different for r=1, . . . , Z.
In one example, which may be a variation of other examples disclosed herein, for one TRP r*, Minit,r* belongs to a first set of values, and for remaining TRPs r≠r*, Minit,r* belongs to a second set of values, where the two sets of values are different. For example, Minit,r*∈{−Wr+1, −Wr+2, . . . , 0} for r=r*, and Minit,r∈{−N3+1, −N3+2, . . . , 0} for r≠r*. The rest of the details are the same as in example II.3.2.4. The one (reference) TRP can be fixed (e.g., TRP of CSI-RS resource with index r*=0), or configured (e.g., via RRC or MAC CE or DCI), or reported by the UE (e.g., as part of the CSI report). In one example, the reference TRP is the strongest TRP (i.e., the TRP whose power or sum of square of coefficient amplitudes is the maximum/largest among Z TRPs). In one example the reference TRP is the TRP associated with strongest coefficient or SCI. The payload for i1,6,r reporting is ┌log2 X┐ bits. The payload for i1,5,r reporting is ┌log2 Wr┐ bits for r=r* and ┌log2 N3┐ bits for r≠r*.
In one example, the window for FD basis vector reporting is independent/separate across TRPs (CSI-RS resources), i.e., one window for each TRP, and Minit for one (reference) TRP is fixed and Minit for each of the remaining Z−1 TRPs is reported. The one (reference) TRP can be fixed (e.g., TRP of CSI-RS resource with index r=0), or configured (e.g., via RRC or MAC CE or DCI), or reported by the UE (e.g., as part of the CSI report). In one example, the reference TRP is the strongest TRP (i.e., the TRP whose power or sum of square of coefficient amplitudes is the maximum/largest among Z TRPs). In one example the reference TRP is the TRP associated with strongest coefficient or SCI. Let r* is the index of the reference TRP. The Minit,r* can be fixed to Minit,r*=0. The Minit,r of each of the remaining TRPs with r≠r*is reported. The details are the same as in various examples disclosed herein. In particular, i1,5,r*=0 (not reported), for each r≠r*, index i1,5,r is reported and indicates Minit,r.
In one example, Wr=Nr=aMr where a can be fixed, e.g., a=2. In one example, Nr is configured. In one example, Wr=min(Nr, N3). Mr FD basis vectors, gf,r=[y0,r(f) y1,r(f) . . . yN
For r≠r*, Minit,r∈{−Wr+1,−Wr+2, . . . ,0}
n
3,r
=[n
3,r
(0)
, . . . ,n
3,r
(M
-1)]
n
3,r
(f)∈{0,1, . . . ,Wr−1}
which are indicated by means of the indices i1,5,r and i1,6,r (for Mr>1), where i1,5,r∈{0, 1, . . . , Wr−1} for r≠r* and i1,6,r∈{0, 1, . . . , X−1}. The UE reports i1,5,r (for r≠r*) and i1,6,r (r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,r(0)=0. In one example,
The payload for i1,6,r reporting is ┌log2 X┐ bits. For r≠r*, the payload for i1,5,r reporting is ┌log2 Wr┐ bits.
In one example, which may be a variation of other examples disclosed herein, for remaining TRPs r≠r*, Minit,r belongs to different set of values. For example, Minit,r∈{−N3+1, −N3+2, . . . , 0} for r≠r*. The rest of the details are the same as in various examples disclosed herein. The payload for i1,5,r reporting is 0 bits for r=r* and ┌log2 N3 ┐ bits for r≠r*.
In one embodiment, a UE can be configured to report Mv or Mv,r FD basis vectors from a set/window of N FD basis vectors, where the Mv or Mv,r FD basis vectors are selected freely (independently) for each layer l∈{1, . . . , v} of a rank v CSI reporting, and the set/window is a subset of a total of N3 basis vectors. In one example, NM≤N3. In one example, NM<N3. The details of the window of basis vectors are as described in various embodiments disclosed herein.
In one example, as described in various embodiments disclosed herein, one common/joint Mv FD basis vectors are determined/reported across all TRPs or CSI-RS resources, and for rank>1, the Mv FD basis vectors are determined/reported independently for each layer l=1, . . . , v.
In one example, when Minit is fixed, it can be fixed, for example, to Minit=0, in which case the window is given by the set of FD indices {n=0, 1, . . . , W−1}, where W=NM or W=min(NM, N3) or W=NM=aMv where a can be fixed, e.g., a=2. The Mv FD basis vectors, gf,l=[y0,l(f) y1,l(f) . . . yN
n
3,l
=[n
3,l
(0)
, . . . ,n
3,l
(M
-1)]
n
3,l
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the indices i1,6,l (for Mv>1), where i1,6,l∈{0, 1, . . . , X−1}. The UE reports i1,6,l (l=1, . . . , v) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l(0)=0. In one example,
The payload for i to reporting is ┌log2 X┐ bits.
In one example, when Minit is reported, it can be reported via an indicator iinit or i1,5, which can be given by:
In one example, W=NM=aM, where a can be fixed, e.g., a=2. In one example, NM is configured. In one example, W=min(NM, N3). The M, FD basis vectors, gf,l=[y0,l(f) y1,l(f) . . . yN
M
init,r
∈{−W+1,−W+2, . . . ,0}
n
3,l
=[n
3,l
(0)
, . . . ,n
3,l
(M
-1)]
n
3,l
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the indices i1,5 and i1,6,l (for Mv>1), where i1,5∈{0, 1, . . . , W−1} and i1,6,l∈{0, 1, . . . , X−1}. The UE reports i1,5 and i1,6,l (l=1, . . . , v) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l(0)=0. In one example,
The payload for i1,6,l reporting is ┌log2 X┐ bits. The payload for i1,5 reporting is ┌log2 W┐ bits.
In one example, as described in various embodiments disclosed herein, for each TRP (CSI-RS resource), Mv,r FD basis vectors are determined/reported independently for each TRP (CSI-RS resource) and for each layer.
In one example, the window for FD basis vector reporting is common/same across TRPs (CSI-RS resources) and Minit is fixed. When Minit is fixed, it can be fixed, for example, to Minit=0, in which case the window is given by the set of FD indices {n=0, 1, . . . , W−1}, where W=NM or W=min(NM, N3) or W=N=aM, r where a can be fixed, e.g., a=2. The Mv,r FD basis vectors, gf,l,r=[y0,l,r(f) y1,l,r(f) . . . yN
n
3,l,r
=[n
3,l,r
(0)
, . . . ,n
3,l,r
(M
-1)]
n
3,l,r
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the indices i1,6,l,r (for Mv,r>1), where i1,6,l,r∈{0, 1, . . . , X−1}. The UE reports i1,6,l,r (l=1, . . . , v and r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l,r(0)=0. In one example,
The payload for i1,6,l,r reporting is ┌log2 X┐ bits.
In one example, the window for FD basis vector reporting is common/same across TRPs (CSI-RS resources) and Minit is reported. When Minit is reported, it can be reported via an indicator iinit or i1,5, which can be given by:
In one example, W=NM=aM where a can be fixed, e.g., a=2. In one example, NM is configured. In one example, W=min(NM, N3). The Mv,r FD basis vectors, gf,l,r=[y0,l,r(f) y1,l,r(f) . . . yN
M
init
∈{−W+1,−W+2, . . . ,0}
n
3,l,r
=[n
3,l,r
(0)
, . . . ,n
3,l,r
(M
-1)]
n
3,l,r
(f)∈{0,1, . . . ,W−1}
which are indicated by means of the indices i1,5 and i1,6,l,r (for Mv,r>1), where i1,5∈{0, 1, . . . , W−1} and i1,6,l,r∈{0, 1, . . . , X−1}. The UE reports i1,5 and i1,6,l,r (l=1, . . . , v and r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l,r(0)=0. In one example,
The payload for i1,6,l,r reporting is ┌log2 X┐ bits. The payload for i1,5 reporting is ┌log2 W┐ bits.
In one example, the window for FD basis vector reporting is independent/separate across TRPs (CSI-RS resources), i.e., one window for each TRP, and Minit is fixed. When Minit is fixed, it can be fixed, for example, to Minit=0, in which case the window for TRP (CSIRS resource) r is given by the set of FD indices {n=0, 1, . . . , Wr−1}, where Wr=Nr or Wr=min(Nr, N3) or Wr=Nr=aMr where a can be fixed, e.g., a=2. The Mv,r FD basis vectors, gf,l,r=[y0,l,r(f) y1,l,r(f) . . . yN
n
3,l,r
=[n
3,l,r
(0)
, . . . ,n
3,l,r
(M
-1)]
n
3,l,r
(f)∈{0,1, . . . ,Wr−1}
which are indicated by means of the indices i1,6,l,r (for Mv,r>1), where i1,6,l,r∈{0, 1, . . . , X−1}. The UE reports i1,6,l,r (l=1, . . . , v and r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l,r(0)=0. In one example,
The payload for i1,6,l,r reporting is ┌log2 X┐ bits.
In one example, the window for FD basis vector reporting is independent/separate across TRPs (CSI-RS resources), i.e., one window for each TRP, and Minit is reported. When Minit,r is reported per TRP r, it can be reported via an indicator iinit,r or i1,5,r, which can be given by:
In one example, Wr=Nr=aMr where a can be fixed, e.g., a=2. In one example, Nr is configured. In one example, Wr=min(Nr, N3). The Mv,r FD basis vectors, gf,l,r=[y0,l,r(f) y1,l,r(f) . . . yN
M
init,r
∈{−W
r+1,−Wr+2, . . . ,0}
n
3,l,r
=[n
3,l,r
(0)
, . . . ,n
3,l,r
(M
-1)]
n
3,l,r
(f)∈{0,1, . . . ,Wr−1}
which are indicated by means of the indices i1,5,r and i1,6,l,r (for Mv,r>1), where i1,5,r∈{0, 1, . . . , Wr−1} and i1,6,l,r∈{0, 1, . . . , X−1}. The UE reports i1,5,r and i1,6,l,r (l=1, . . . , v and r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l,r=0. In one example,
The payload for reporting i1,6,l,r is ┌log2 X┐ bits. The payload for i1,5,r reporting is ┌log2 Wr┐ bits.
In one example, Minit,r=Minit when the same (one) value for Minit is reported for all TRPs, and in this case, it can be reported via an indicator iinit or i1,5. Note Wr can be the same or different for r=1, . . . , Z.
In one example, Minit,r can be the same or different across TRPs, and in this case, Wr can be the same or different for r=1, . . . , Z.
In one example, which may be a variation of other examples disclosed herein, for one TRP r*, Minit,r* belongs to a first set of values, and for remaining TRPs r≠r*, Minit,r* belongs to a second set of values, where the two sets of values are different. For example, Minit,r*∈{−Wr+1, −Wr+2, . . . , 0} for r=r*, and Minit,r∈{−N3+1, −N3+2, . . . , 0} for r≠r*. The rest of the details are the same as in example II.4.2.4. The one (reference) TRP can be fixed (e.g., TRP of CSI-RS resource with index r*=0), or configured (e.g., via RRC or MAC CE or DCI), or reported by the UE (e.g., as part of the CSI report). In one example, the reference TRP is the strongest TRP (i.e., the TRP whose power or sum of square of coefficient amplitudes is the maximum/largest among Z TRPs). In one example the reference TRP is the TRP associated with strongest coefficient or SCI. The payload for i1,6,l,r reporting is ┌log2 X┐ bits. The payload for i1,5,r reporting is ┌log2 Wr┐ bits for r=r* and ┌log2 N3┐ bits for r≠r*.
In one example, the window for FD basis vector reporting is independent/separate across TRPs (CSI-RS resources), i.e., one window for each TRP, and Minit for one (reference) TRP is fixed and Minit for each of the remaining Z−1 TRPs is reported. The one (reference) TRP can be fixed (e.g., TRP of CSI-RS resource with index r=0), or configured (e.g., via RRC or MAC CE or DCI), or reported by the UE (e.g., as part of the CSI report). In one example, the reference TRP is the strongest TRP (i.e., the TRP whose power or sum of square of coefficient amplitudes is the maximum/largest among Z TRPs). In one example the reference TRP is the TRP associated with strongest coefficient or SCI. Let r* is the index of the reference TRP. The Minit,r* can be fixed to Minit,r*=0. The Minit,r of each of the remaining TRPs with r≠r*is reported. The details are the same as in example II.4.2.4. In particular, i1,5,r*=0 (not reported), for each r≠r*, index i1,5,r is reported and indicates Minit,r.
In one example, Wr=Nr=aMr where a can be fixed, e.g., a=2. In one example, Nr is configured. In one example, Wr=min(Nr, N3). The Mv,r FD basis vectors, gf,l,r=[y0,l,r(f) y1,l,r(f) . . . yN
For r≠r*, Minit,r∈{−Wr+1,−Wr+2, . . . ,0}
n
3,l,r
=[n
3,l,r
(0)
, . . . ,n
3,l,r
(M
-1)]
n
3,l,r
(f)∈{0,1, . . . ,Wr−1}
which are indicated by means of the indices i1,5,r and i1,6,l,r (for Mv,r>1), where i1,5,r∈{0, 1, . . . , Wr−1} for r≠r* and i1,6,l,r∈{0, 1, . . . , X−1}. The UE reports i1,5,r (for r≠r*) and i1,6,l,r (l=1, . . . , v and r=1, . . . , Z) via the PMI included in the CSI report. In one example,
when one of the FD basis vectors is fixed, e.g., n3,l,r(0)32 0. In one example,
The payload for i1,6,l,r reporting is ┌log2 X┐ bits. For r≠r*, the payload for i1,5,r reporting is ┌log2 W┐ bits.
In one example, which may be a variation of other examples disclosed herein, for remaining TRPs r≠r*, Minit,r belongs to different set of values. For example, Minit,r∈{−N3+1, −N3+2, . . . , 0} for r≠r*. The rest of the details are the same as in various examples disclosed herein. The payload for i1,5,r reporting is 0 bits for r=r* and ┌log2 N3┐ bits for r≠r*.
In one embodiment, the UE is configured to report M or Mr or Mv or Mv,r FD basis vectors according to window-based embodiments and free selection embodiments disclosed herein, based on a condition. The condition is according to at least one of the following examples.
In one embodiment, the UE is configured with a CSI report based on a codebook, where as described in above, the codebook can be configured to be one of the following:
For these codebook configuration, C1 through C4, the UE is further configured to determine/report FD basis vectors according to at least one of the following examples.
In one example, the UE is further configured to determine/report FD basis vectors according to the same scheme for all codebook configuration C1-C4, where the same scheme to determine/report FD basis vectors is according to one of the examples in various embodiments disclosed herein. In one example, this same scheme can be various examples disclosed herein.
In one example, the UE is further configured to determine/report FD basis vectors according to a scheme that is configured for all codebook configuration C1-C4, where the configured scheme to determine/report FD basis vectors is according to one of the examples in various embodiments disclosed herein. In one example, this configured scheme can be various examples disclosed herein.
In one example, the UE is further configured to determine/report FD basis vectors according to two different schemes (scheme A and scheme B), where scheme A is used for S1, and scheme B is used for S2.
In one example, scheme A is according to various examples disclosed herein and scheme B is according to various examples disclosed herein.
In one example, the UE is further configured to determine/report FD basis vectors according to three different schemes (scheme A, scheme B, and scheme C), where scheme A is used for S1, scheme B is used for S2, and scheme C is used S3.
In various examples, scheme A is according to various examples disclosed herein, scheme B is according to various examples disclosed herein, and scheme C is according to various examples disclosed herein.
In one example, when the codebook is according to (C1) or (C2), then at least one of the following examples is used.
In one example, when the codebook is according to (C3) or (C4), then at least one of the following examples is used.
In one embodiment, when Minit for different TRPs (CSI-RS resources) are determined separately/independently (cf. various examples disclosed herein), then the different Minit values can be determined (or reported) relative to (or w.r.t.) to a reference TRP (CSI-RS resource). In this case, the different (relative) Minit values can be equivalently described as ‘relative’ FD offsets, i.e., Minit,r for a TRP r equals a relative FD offset for the TRP r denoted as Or or ψr (as described earlier). In one example, the reference TRP is denoted as r*, as described earlier in this disclosure. In one example, the reference TRP or CSI-RS resource can be the first (index r=0 or r=1) of the N selected CSI-RS resources. For the reference TRP, we can assume that Minit,r*=Or*=ωr*=0. For the remaining TRPs (r≠r*), Minit,r or Or or ψr is determined and hence needs reporting.
In one example, r*=1, and when codebookMode is set to ‘mode1’, N−1 phase offsets for r=2, . . . ,N CSI-RS resources are reported by the UE.
In one example, r*=1, and when codebookMode is set to ‘mode1’, phase offsets are not reported, and ψr=0 for r=1, . . . , N.
In one example, for the case when Lr=L for all r, the indicators i2,3,l, i2,4,l, and i1,7,l can be described as follows.
The amplitude coefficient indicators i2,3,l and i2,4,l, for l=1, . . . , v, are:
i
2,3,l
[k
l,0
(1)
k
l,1
(1)]
k
l,p
(1)
=[k
l,p,0
(2)
. . . k
l,p,Z-1
(2)]
i
2,4,l
=[k
l,0
(2)
. . . k
l,M
-1
(2)]
k
l,f
(2)
=[k
l,0,f
(2)
. . . k
l,2,L-1,f
(2)]
k
l,i,f
(2)
=[k
l,i,f,0
(2)
. . . k
l,i,f,Z-1
(2)]
k
l,p,r
(1)∈{1, . . . ,15}
k
l,i,f,r
(2)∈{0, . . . ,7}.
for l=1, . . . , v.
The phase coefficient indicator i2,5,l, for l=1, . . . , v, is:
i
2,5,l
=[c
l,0
. . . c
l,M
-1]
c
l,f
=[c
l,0,f
. . . c
l,2L-1,f]
c
l,i,f
=[c
l,i,f,0
. . . c
l,i,f,Z-1]
c
l,i,f,r∈{0, . . . ,15}
for l=1, . . . , v.
The bitmap whose nonzero bits identify which coefficients in i2,4,l and i2,5,l are reported, is indicated by i1,7,l
i
1,7,l
=[k
l,0
(3)
. . . k
l,M
-1
(3)]
k
l,f
(3)
=[k
l,0,f
(3)
. . . k
l,2L-1,f
(3)]
k
l,i,f
(3)
=[k
l,i,f,0
(3)
. . . k
l,i,f,Z-1
(3)]
k
l,i,f,r
(3)∈{0,1}
for l=1, . . . , v. In one example, KlNZ=Σr=0Z-1Σi=02L-1Σf=M
In one example, for the case when Lr can be different across r values, L needs to be replaced with Lr. In that case, the amplitude coefficient indicator i2,4,l, and the bitmap indicator
i
1,7,l for layer l=1, . . . , v, can be given by:
i
2,4,l=[2,4,l,1 . . . i2,4,l,Z]
i
2,4,l,r
=[k
l,0,r
(2)
k
l,M
-1,r
(2)]
k
l,f,r
(2)
=[k
l,0,f,r
(2)
. . . k
l,2L
-1,f,r
(2)]
k
l,i,f,r
(2)∈{0, . . . ,7}
i
1,7,l
=[i
1,7,l,1
. . . i
1,7,l,Z]
i
1,7,l,r
[k
l,0,r
(3)
k
l,M
-1,r
(3)]
k
l,f,r
(3)
[k
l,0,f,r
(3)
. . . k
l,2L
-1,f,r
(3)]
k
l,i,f,r
(3)∈{0,1}
In one embodiment, there is one strongest coefficient across all Z TRPs and there can be remapping of FD indices performed w.r.t. the FD index of the strongest coefficient.
In one example, for the case when Lr=L, let f*l∈{0, 1, . . . , Mv−1} be the index of i2,4,l, i*l∈{0, 1, . . . , 2L−1} be the index of kl,f*
In one example, for the case when Lr can be different across r values, let f*l∈{0, 1, . . . , Mv−1} and l*l∈{0, 1, . . . , 2 Σr=1Z Lr−1} be the indices which identify the strongest (2) coefficient of layer l, for l=1, . . . , v, i.e., the element kl,i*
The codebook indices of n3,l,r can be remapped with respect to n3,l,r(f*
When the FD basis vectors are the same for all TRPs or CSI-RS resources, the subscript r from n3,l,r and n3,l,r(f*
In one example, a joint indicator (l*l) is used to indicate (i*l, r*l). For the case when Lr=L, the strongest coefficient of layer l is identified by the joint indicator i1,8,l∈{0, 1, . . . , 2LZ−1}, which is obtained as follows. When r∈{0, 1, . . . , Z−1}
i
1,8,l
=l*
l=2Lr*l+i*l or
i
1,8,l
=l*
l
=Zi*
l
+r*
l
for l=1, . . . , v. Or, when r∈{1, . . . , Z}
i
1,8,l
=l*
l=2L(r*l−1)+i*l or
i
1,8,l
=l*
l
=Zi*
l+(r*l−1).
For the case when Lr can be different across r values, the strongest coefficient of layer l is identified by the joint indicator i1,8,l∈{0, 1, . . . , 2 Σr=1Z Lr−1}, which is obtained as:
i
1,8,l
=l*
l∈{0,1, . . . ,2Σr=1ZLr−1}.
The payload for reporting i1,8,l therefore is ┌log2 (2LZ)┐ or ┌log2 (2 Σr=1Z Lr)┐ bits. Similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 38.214),
and cl,i*
kl,i*
In one example, depending on the rank value v, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as follows. For the case when Lr=L, l1,8,l=(Σi=0i*
For the case when Lr can be different across r values, the strongest coefficient of layer l is identified by the joint indicator i1,8,l∈{0, 1, . . . , 2 Σr=1Z Lr−1}, which is obtained according to at least one of the following examples.
In one example, the strongest coefficient of layer l=1, . . . , v is identified by:
i
1,8,l∈{0,1, . . . ,2Σr=1ZLr−1},
which, depending on the rank value v is obtained as follows:
for l=1, . . . , v.
In one example, let Sr,V=Σi=0V k1,i,0,r(3) where Σr=10 Sr,2L
In one example, let Sr*
In one example, i1,8,l is obtained as follows:
where let κ1,l,0(3)=k1,10,r(3), where I is an index which maps to an index pair (i, r) of an SD index i and CSI-RS resource r, and is given by I=2 Σk=1r-1 Lr+i. For a given I, the index pair (i, r) can be obtained as follows:
Alternatively, for a given I, the index pair (i, r) can be obtained as follows:
In one example, two separate indicators are used to indicate (i*l, r*l). The TRP (CSI-RS resource) index r*l is identified by a first indicator i1,9,l∈{0, 1, . . . , Z−1}, and the corresponding strongest coefficient of layer l is identified by the second indicator i1,8,l∈{0, 1, . . . , 2L−1}, which are obtained as follows:
i
1,8,l
=i*
l and i1,9,l=r*l
for l=1, . . . , v. The payload for reporting i1,8,l and i1,9,l therefore are ┌log2(2L)┐ bits and ┌log2(Z)┐ bits, respectively. Similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 0.56.214),
and cl,i*
and cl,i*
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l=Σi=0l*1 k1,i,0,r*
In one embodiment, there is one strongest coefficient across all Z TRPs and there is no remapping of FD indices performed.
In one example, for the case when Lr=L, let f*l∈{0, 1, . . . , Mv−1} be the index of i2,4,l, i*l∈{0, 1, . . . , 2L−1} be the index of kl,f*
In one example, for the case when Lr can be different across r values, let f*l∈{0, 1, . . . Mv−1} and I*l∈{0, 1, . . . , Σr=1Z K1,r−1} be the indices which identify the strongest (2) coefficient of layer l, for l=1, . . . , v, i.e., the element kl,i*
K1,r ports are selected from the PCSI-RS ports of the r-th selected CSI-RS resource, for r=1, . . . , Z, based on Lr vectors, vm
Let
the index i1,2,r, for the r-th selected CSI-RS resource, r=1, . . . , Z, is obtained from the Lr elements of mr, as described in Clause 5.2.2.2.7 of TS 38.214 for the indicator i1,2, obtained from the L elements of m. Vector vm
In one example, a joint indicator is used to indicate (i*l, f*l, r*l). For the case when Lr=L, the strongest coefficient of layer l=1, . . . , v is identified by the index:
i
1,8,l∈{0,1, . . . ,2LMvZ−1}
which is found from:
i
1,8,l=2LMvr*l+2Lf*l*+i*l, or
i
1,8,l=2LMvr*l+Mvi*l+f*l, or
i
1,8,l
=M
v
Zi*
l
+M
v
r*
l
+f*
l, or
i
1,8,l
=M
v
Zi*
l
+Zf*
l
+r*
l, or
i
1,8,l=2LZf*l+2Lr*l+i*l, or
i
1,8,l=2LZf*l+Zi*l+r*l
for l=1, . . . , v.
For the case when Lr can be different across r values (example B above), the strongest coefficient of layer l is identified by the joint indicator i1,8,l∈{0, 1, . . . , 2Mv Σr=1Z Lr−1}={0, 1, . . . Mv Σr=1Z K1,r−1}, which is obtained as:
i
1,8,l
=f*
lΣr=1ZK1,r+I*l.
In one example, Mv=M.
The payload for reporting i1,8,l therefore is ┌log2(2LMvZ)┐ or ┌log2(2Mv Σr=1Z Lr┐=┌log2(Mv Σr=1Z K1,r)┐ bits. Similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 38.214),
and cl,i*
and cl,i*
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l=(Σr=0Z-1 Σi=02L-1 Σf=0M
In one example, two indicators are used to indicate (i*l, f*l) and r*l separately. The TRP (CSI-RS resource) index r*l is identified by a first indicator i1,9,l∈{0, 1, . . . , Z−1}, and the corresponding strongest coefficient of layer l is identified by the second indicator i1,8,l∈{0, 1, . . . , 2LMv−1}, which are obtained as follows:
i
1,8,l=2Lf*l+i*l or i1,8,l=Mvi*l+f*l, and i1,9,l=r*l
for l=1, . . . , v. The payload for reporting i1,8,l and i1,9,l therefore are ┌log2(2LMv)┐ bits and ┌log2(Z)┐ bits, respectively. Similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 38.214), kl,i*
and cl,i*
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l=(Σi=0i*
In one example, two indicators are used to indicate (i*l, r*l) and f*l separately. The FD index f*l is identified by a first indicator i1,9,l∈{0, 1, . . . , Mv−1}, and the corresponding strongest coefficient of layer l is identified by the second indicator i1,8,l∈{0, 1, . . . , 2LZ−1}, which are obtained as follows:
i
1,8,l=2Lr*l++i*l or i1,8l=Zi*l+r*l, and i1,9,l=f*l,
for l=1, . . . , v. The payload for reporting i1,8,l and i1,9,l therefore are ┌log2(2LZ)1 bits and ┌log2(Mv)┐ bits, respectively. Similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 38.214), kl,i*
and cl,i*
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l=(Σi=0i*
In one example, two indicators are used to indicate (f*l, r*l) and i*l separately. The SD index i*l is identified by a first indicator i1,8,l∈{0, 1, . . . , 2L−1}, and the corresponding strongest coefficient of layer l is identified by the second indicator i1,9,l∈{0, 1, . . . , MvZ−1}, which are obtained as follows:
i
1,8,l
=i*
l and i1,9,l=Zf*l+r*l or i1,9,l=Mvr*l+f*l,
for l=1, . . . , v. The payload for reporting i1,8,l and i1,9,l therefore are ┌log2(2L)┐ bits and ┌log2(MvZ)┐ bits, respectively. Similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 38.214), kl,i*
and cl,i*
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l=(Σf=0f*
In one example, three indicators are used to indicate i*l, f*l, and r*l separately. The SD index i*l is identified by a first indicator i1,8,l∈{0, 1, . . . , 2L−1}, the FD index f*l is identified by a second indicator i1,9,l∈{0, 1, . . . , Mv−1}, and the TRP index r*l is identified by a second indicator i1,10,l∈{0, 1, . . . , Z−1}, which are obtained as follows:
i
1,8,l
=i*
l and i1,9,l=f*l and i1,10,l=r*l,
for l=1, . . . , v. The payload for reporting i1,8,l, i1,9,l, and i1,10,l therefore are ┌log2(2L)┐ bits, ┌log2(Mv)┐ bits, and ┌log2(Z)┐ bits, respectively. Similar to Rel. 16 enhanced Type II codebook (5.2.2.2.5, 38.214),
and cl,i*
and cl,i*
In one embodiment, there is one strongest coefficient for each TRP (i.e., Z SCIs in total), and there can be remapping of FD indices performed w.r.t. the FD index of one of the Z strongest coefficients, the details of the remapping are as described in embodiment III.1. Let r*l be the index w.r.t. which the remapping is applied. Let f*l,r
and rl∈{0, 1, . . . , Z−1} be the index of
which identify the strongest coefficient of layer l and TRP rl, i.e., the element
of i2,4,l, for l=1, . . . , v.
The strongest coefficients of layer l are identified by indicators i1,8,l,r
i
1,8,l,y*
∈{0, 1, . . . ,2L−1} and
i
1,8,l,r
∈{0, 1, . . . ,2LMv−1} for rl≠r*l
which are obtained as follows:
i
1,8,l,r*
i=i*
l,r*
i
1,8,l,r
=2Lf*l,r
for l=1, . . . , v. The payload for reporting i1,8,l,r*
The indicators
are not reported for l=1, . . . , v.
Note that f*l,r*
The indicators
are not reported for l=1, . . . , v.
The TRP index r*l can be identified by a second indicator i1,10,l∈{0, 1, . . . , Z−1}. The payload for reporting i1,10,l therefore is ┌log2(Z)┐ bits.
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l,r=(Σi=0i*
In one embodiment, there is one strongest coefficient for each TRP (i.e., Z SCIs in total), and there can be remapping of FD indices performed w.r.t. the FD index of one of the Z strongest coefficients, the details of the remapping are as described in various embodiments disclosed herein. Let r*l be the index w.r.t. which the remapping is applied. Let f*l,r
and rl∈{0, 1, . . . , Z−1} be the index of
which identify the strongest coefficient of layer l and TRP rl, i.e., the element
of i2,4,l, for l=1, . . . , v.
The strongest coefficients of layer l are identified by indicators i1,8,l,r
i
1,8,l,r*
∈{0,1, . . . ,2LZ−1} and
i
1,8,l,r
∈{0,1, . . . ,2LMv−1} for rl≠r*l
which are obtained as follows:
i
1,8,l,r*
Zi*
l,r*
+r*
l or 2Lr*i+i*l,r
i
1,8,l,r
=2Lf*l,r
for l=1, . . . , v. Note that is a joint indicator to indicate (r*l, i*l,r
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l,r=(Σi=0i*
In one embodiment, there is one strongest coefficient for each TRP (i.e., Z SCIs in total), and there is no remapping of FD indices performed.
The strongest coefficients of layer l are identified by indicators i1,8,l,r
i
1,8,l,r
∈{0,1, . . . ,2LMv−1}
which are obtained as follows:
i
1,8,l,r
=2Lf*l,r
for l=1, . . . , v. The payload for reporting i1,8,l,r
The indicators
are not reported for l=1, . . . , v.
In one example, for rank>1 (i.e., v>1, e.g., 1<v≤4), the SCI is obtained and reported as above, and for rank=1 (v=1), the SCI is obtained (from the bitmap) as i1,8,l,r=(Σi=0i*
The method 1700 begins with the UE receiving a configuration about a CSI report (1710). For example, in 1710, the configuration includes information about (i) NTRPg non-zero power (NZP) CSI-reference signal (RS) resources, where NTRP≥1, and (ii) a parameter codebookType set to type-II-CJT-r18 or type-II-PortSelection-CJT-r18.
The UE then, based on the configuration, determines, for each layer l=1, . . . , v, an indicator i1,8,l for indicating an index (i*l, f*l, r*l) of a strongest coefficient among KlNZ coefficients (1720). For example, in 1720 where KlNZ is a total number of non-zero coefficients that are associated with Z NZP CSI-RS resources, and Z≤NTRP.
The UE then, based on the configuration, determines, for each layer l=1, . . . , v, a number of bits Pl for the indicator i1,8,l (1730). For example, in 1730, when codebookType=type-II-CJT-r18, a value of Pl depends on a value of KlNZ, when v=1, and a value of Σr=1Z Lr, when 1<v≤4. When codebookType=type-II-PortSelection-CJT-r18, the value of Pl depends on a value of 2Mv Σr=1Z Lr for all values of v. Here, v is a total number of layers, Lr is a number of first basis vectors associated with an r-th NZP CSI-RS resource from the Z NZP CSI-RS resources, where r=1, . . . , Z, Mv is a number of second basis vectors, i*l∈{0, . . . , 2Lr*
In various embodiments, when codebookType=type-II-CJT-r18, Pl=P1=┌log2 K1NZ┐ when v=1 and Pl=┌log2(2 Σr=1Z Lr)┐ when 1<v≤4. For example, i1,8,l∈{0, 1, . . . , 2 Σr=1Z Lr−1} and is obtained as:
where κ1,l,0(3)=k1,i,0,r(3), and I is an index given by I=2 Σr=1r-1 Lr+i, kl,i,f,r(3)=0 or 1 to indicate a coefficient with an index (i, f, r) being zero or non-zero, respectively, and I*l∈{0, 1, . . . , 2 Σr=1Z Lr−1} and is given by I*l=2 Σkr=1r*
In various embodiments, when codebookType=type-II-PortSelection-CJT-r18, Pl=┌log2(Mv Σr=1Z K1,r)┐. For example, i1,8,l∈{0, 1, . . . , 2Mv Σr=1Z Lr−1} and is obtained as:
where I*l∈{0, 1, . . . , Σr=1Z K1,r−1} and is given by I*l=Σr=1r*
In various embodiments, when codebookType=type-II-CJT-r18, the UE may, for each layer l, remap indices of second basis vectors n3,l(f), where f=0, . . . , Mv−1, with respect to n3,l(f*
In various embodiments, the configuration includes a parameter codebookMode, and when codebookMode=mode1, the UE determines a second basis vector offset Or for each NZP CSI-RS resource r such that O1=0, and Or∈{0, 1, . . . , N3−1} for r=2, . . . , Z, and transmits the CSI report including an indicator indicating a value of Or for each r=2, . . . , Z.
In various embodiments, when codebookType=type-II-CJT-r18, the first basis vectors comprise DFT vectors and, when codebookType=type-II-PortSelection-CJT-r18, the first basis vectors comprise port selection vectors. The second basis vectors comprise DFT vectors with indices belonging to a window of indices given by mod(Minit+n, N3), where n=0, 1, . . . , W−1, and W<N3. Further, when codebookType=type-II-CJT-r18, the CSI report include an indicator indicating a value of Minit, and when codebookType=type-II-PortSelection-CJT-r18, Minit=0.
Any of the above variation embodiments can be utilized independently or in combination with at least one other variation embodiment.
The above flowcharts illustrate example methods that can be implemented in accordance with the principles of the present disclosure and various changes could be made to the methods illustrated in the flowcharts herein. For example, while shown as a series of steps, various steps in each figure could overlap, occur in parallel, occur in a different order, or occur multiple times. In another example, steps may be omitted or replaced by other steps.
Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims. None of the description in this application should be read as implying that any particular element, step, or function is an essential element that must be included in the claims scope. The scope of patented subject matter is defined by the claims.
This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63/403,176 filed on Sep. 1, 2022, U.S. Provisional Patent Application No. 63/441,350 filed on Jan. 26, 2023, and U.S. Provisional Patent Application No. 63/471,686 filed on Jun. 7, 2023. The above-identified provisional patent applications are hereby incorporated by reference in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63403176 | Sep 2022 | US | |
| 63441350 | Jan 2023 | US | |
| 63471686 | Jun 2023 | US |
