The present disclosure relates generally to wireless communication systems and, more specifically, to electronic devices and methods for codebook subset restriction for coherent joint transmission (C-JT) in wireless networks.
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 apparatuses and methods for codebook subset restriction for coherent joint transmission.
In one embodiment, a user equipment (UE) is provided. The UE includes a transceiver configured to receive information about a channel state information (CSI) report associated with NTRP>1 groups of antenna ports. The information indicates (i) a coherent joint transmission (CJT) codebook, (ii) a rank restriction, and (iii) NTRP codebook subset restrictions (CBSRs). The UE further includes a processor operably coupled to the transceiver. The processor is configured to identify, based on the rank restriction, a set S1 of one or more rank values allowed for the CSI report, identify, based on the NTRP CBSRs, sets S2,1, . . . , S2,N
In another embodiment, a base station (BS) is provided. The BS includes a processor configured to identify information about a CSI report associated with NTRP>1 groups of antenna ports. The information indicates (i) a CJT codebook, (ii) a rank restriction, and (iii) NTRP CBSRs. The BS further includes a transceiver operably coupled to the processor. The transceiver is configured to transmit the information to the CSI report and receive the CSI report. The rank restriction indicates a set S1 of one or more rank values allowed for the CSI report. The NTRP CBSRs indicate sets S2,1, . . . , S2,N
In yet another embodiment, a method performed by a UE is provided. The method includes receiving information about a CSI report associated with NTRP>1 groups of antenna ports. The information indicates (i) a CJT codebook, (ii) a rank restriction, and (iii) NTRP CBSRs. The method further includes identifying, based on the rank restriction, a set S1 of one or more rank values allowed for the CSI report; identifying, based on the NTRP CBSRs, sets S2,1, . . . , S2,N
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 v17.2.0, “E-UTRA, Physical channels and modulation” (herein “REF 1”); 3GPP TS 36.212 v17.1.0, “E-UTRA, Multiplexing and Channel coding” (herein “REF 2”); 3GPP TS 36.213 v17.2.0, “E-UTRA, Physical Layer Procedures” (herein “REF 3”); 3GPP TS 36.321 v17.1.0, “E-UTRA, Medium Access Control (MAC) protocol specification” (herein “REF 4”); 3GPP TS 36.331 v17.1.0, “E-UTRA, Radio Resource Control (RRC) Protocol Specification” (herein “REF 5”); 3GPP TS 38.211 v17.2.0, “NR, Physical channels and modulation” (herein “REF 6”); 3GPP TS 38.212 v17.2.0, “NR, Multiplexing and Channel coding” (herein “REF 7”); 3GPP TS 38.213 v17.2.0, “NR, Physical Layer Procedures for Control” (herein “REF 8”); 3GPP TS 38.214 v17.2.0, “NR, Physical Layer Procedures for Data” (herein “REF 9”); 3GPP TS 38.215 v17.1.0, “NR, Physical Layer Measurements” (herein “REF 10”); 3GPP TS 38.321 v17.1.0, “NR, Medium Access Control (MAC) protocol specification” (herein “REF 11”); 3GPP TS 38.331 v17.1.0, “NR, Radio Resource Control (RRC) Protocol Specification” (herein “REF 12”).
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.
As shown in
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 for supporting codebook subset restriction for coherent joint transmission. In certain embodiments, one or more of the BSs 101-103 include circuitry, programing, or a combination thereof for supporting codebook subset restriction for coherent joint transmission.
Although
As shown in
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. As another example, the controller/processor 225 could support methods for supporting codebook subset restriction for coherent joint transmission. 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 an OS. 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.
Although
As shown in
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. As another example, the processor 340 could support methods for codebook subset restriction for coherent joint transmission. 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. 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).
Although
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
Since the above system utilizes multiple analog beams for transmission and reception (wherein one or a small number of analog beams are selected out of a large number, for instance, after a training duration—to be performed from time to time), the term “multi-beam operation” is used to refer to the overall system aspect. This includes, for the purpose of illustration, indicating the assigned DL or UL transmit (TX) beam (also termed “beam indication”), measuring at least one reference signal for calculating and performing beam reporting (also termed “beam measurement” and “beam reporting”, respectively), and receiving a DL or UL transmission via a selection of a corresponding receive (RX) beam.
The above system is also applicable to higher frequency bands such as >52.6 GHz (also termed the FR4). In this case, the system can employ only analog beams. Due to the O2 absorption loss around 60 GHz frequency (˜10 dB additional loss @ 100 m distance), larger number of and sharper analog beams (hence larger number of radiators in the array) will be needed to compensate for the additional path loss.
At lower frequency bands such as <1 GHz, on the other hand, the number of antenna elements may not be large in a given form factor due to the large wavelength. As an example, for the case of the wavelength size (λ) of the center frequency 600 MHz (which is 50 cm), it desires 4 m for uniform-linear-array (ULA) antenna panel of 16 antenna elements with the half-wavelength distance between two adjacent antenna elements. Considering a plurality of antenna elements is mapped to one digital port in practical cases, the desirable size for antenna panel(s) at gNB to support a large number of antenna ports such as 32 CSI-RS ports becomes very large in such low frequency bands, and it leads the difficulty of deploying 2-D antenna element arrays within the size of a conventional form factor. This results in a limited number of CSI-RS ports that can be supported at a single site and limits the spectral efficiency of such systems.
Various embodiments of the present disclosure recognize that for a cellular system operating in a sub-1 GHz frequency range (e.g., less than 1 GHz), supporting large number of CSI-RS antenna ports (e.g., 32) at a single location or remote radio head (RRH) or TRP is challenging due to that a larger antenna form factor size is needed at these frequencies than a system operating at a higher frequency such as 2 GHz or 4 GHz. At such low frequencies, the maximum number of CSI-RS antenna ports that can be co-located at a single site (or TRP/RRH) can be limited, for example to 8. This limits the spectral efficiency of such systems. In particular, the MU-MIMO spatial multiplexing gains offered due to large number of CSI-RS antenna ports (such as 32) can't be achieved.
One way to operate a sub-1 GHz system with large number of CSI-RS antenna ports is based on distributing antenna ports at multiple locations (or TRP/RRHs). The multiple sites or TRPs/RRHs can still be connected to a single (common) base unit, hence the signal transmitted/received via multiple distributed TRPs/RRHs can still be processed at a centralized location. This is called distributed MIMO or multi-TRP coherent joint transmission (C-JT).
Various embodiments of the present disclosure recognize that CSI enhancement described in Rel-18 MIMO considers Rel-16/17 Type-II CSI codebook refinements to support mTRP coherent joint transmission (C-JT) operations by considering performance-and-overhead trade-off. Various embodiments of the present disclosure recognize that utilizing codebook subset restriction (CBSR) is one of the ways to manage CSI feedback overhead. Especially, in multi-TRP C-JT scenarios, CBSR could be useful in terms of reducing overhead.
Accordingly, various embodiments of the present disclosure provide mechanisms for CBSR for multi-TRP C-JT scenarios.
One possible approach to resolving the issue is to form multiple TRPs (multi-TRP) or RRHs with a small number of antenna ports instead of integrating all of the antenna ports in a single panel (or at a single site) and to distribute the multiple panels in multiple locations/sites (or TRPs, RRHs). This approach is shown in
As illustrated in
Note that although the present disclosure has mentioned low frequency band systems (sub-1 GHz band) as a motivation for distributed MIMO (or mTRP), the distributed MIMO technology is frequency-band-agnostic and can be useful in mid- (sub-6 GHz) and high-band (above-6 GHz) systems in addition to low-band (sub-1 GHz) systems.
The terminology “distributed MIMO” is used as an illustrative purpose, it can be considered under another terminology such as multi-TRP, mTRP, cell-free network, and so on.
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 consist 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” 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), we assume that each panel is 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 (coherent joint-transmission) 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.
The remainder of the present disclosure assumes a structured antenna architecture. For simplicity, in the remainder of the present disclosure it is assumed that each RRH/TRP is equivalent to a panel, although, an RRH/TRP can have multiple panels in practice. The present disclosure however is not restrictive to a single panel assumption at each RRH/TRP, and can easily be extended (covers) the case when an RRH/TRP has multiple antenna panels.
In one embodiment, an RRH constitutes (or corresponds to or is equivalent to) at least one of the following:
In one example, when RRH or TRP maps (or corresponds to) a CSI-RS resource or resource group, and a UE can select a subset of RRHs (resources or resource groups) and report the CSI for the selected TRPs/RRHs (resources or resource groups), the selected TRPs/RRHs 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 or TRP maps (or corresponds to) a CSI-RS port group, and a UE can select a subset of TRPs/RRHs (port groups) and report the CSI for the selected TRPs/RRHs (port groups), the selected TRPs/RRHs 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 TRPs/RRHs, a decoupled (modular) codebook is used/configured, and when a single (K=1) CSI-RS resource for NRRH TRPs/RRHs, 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 5.2.2.2.6 of REF8, a UE is configured with higher layer parameter codebookType set to ‘typeII-PortSelection-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 (υ=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
w
f
[y
0,l
(f)
y
1,l
(f)
. . . y
N
−1,l
(f)]T,
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
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 [REF8], and B=Wf.
The Cl={tilde over (W)}2 matrix consists of 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 signaling. In another example, the amplitude coefficient (pl,i,f) is reported as pl,i,f=pl,i,f(1)pl,i,f(2) where
For layer l, let us denote the linear combination (LC) coefficient associated with spatial domain (SD) basis vector (or beam) i∈{0, 1, . . . , 2L−1} and frequency domain (FD) basis vector (or beam) f∈{0, 1, . . . , M−1} as cl,i,f, and the strongest coefficient as cl,i*,f*. The strongest coefficient is reported out of the KNZ non-zero (NZ) coefficients that is reported using a bitmap, where KNZ≤K0=┌β×2LM┐<2LM and β is higher layer configured. The remaining 2LM−KNZ coefficients that are not reported by the UE are assumed to be zero. The following quantization scheme is used to quantize/report the KNZ NZ coefficients.
For the polarization r*∈{0,1} associated with the strongest coefficient cl,i*,f*, we have
and the reference amplitude pl,i,f(1)=pl,r*(1)=1. For the other polarization r∈{0,1} and r≠r*, we have
and the reference amplitude pl,i,f(1)=pl,r(1) is quantized (reported) using the 4-bit amplitude codebook mentioned above.
In Rel. 16 enhanced Type II and Type II port selection codebooks, a UE can be configured to report M FD basis vectors. In one example,
where R is higher-layer configured from {1,2} and p is higher-layer configured from
In one example, the p value is higher-layer configured for rank 1-2 CSI reporting. For rank>2 (e.g., rank 3-4), the p value (denoted by v0) can be different. In one example, for rank 1-4, (p, v0) is jointly configured from
i.e.,
for rank 1-2 and
for rank 3-4. In one example, N3=NSB×R where NSB is the number of SBs for CQI reporting. In one example, M is replaced with Mv to show its dependence on the rank value v, hence p is replaced with pv, v∈{1,2} and v0 is replaced with pv, v∈{3,4}.
A UE can be configured to report Mv FD basis vectors in one-step from N3 basis vectors freely (independently) for each layer l∈{1, . . . , v} of a rank v CSI reporting. Alternatively, a UE can be configured to report Mv FD basis vectors in two-step as follows.
In one example, one-step method is used when N3≤19 and two-step method is used when N3>19. In one example, N′3=┌αMv┐ where α>1 is either fixed (to 2 for example) or configurable.
The codebook parameters used in the DFT based frequency domain compression (Eq. 5) are (L, pv for v∈{1,2}, pv for v∈{3,4}, β, α, Nph). The set of values for these codebook parameters are as follows.
In Rel. 17 (further enhanced Type II port selecting codebook),
where K1=α×PCSIRS, and codebook parameters (M, α, β) are configured from Table 2.
The above-mentioned framework (Eq. 5) represents the precoding-matrices for multiple (N3) FD units using a linear combination (double sum) over 2L (or K1) SD beams/ports 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.
In one example, the codebook for the CSI report is according to at least one of the following examples.
In one example, when the codebook is a legacy codebook (e.g., one of Rel. 15/16/17 NR codebooks, according to one of the examples above), then the CSI reporting is based on a CSI resource set comprising one or multiple NZP CSI-RS resource(s), where each NZP CSI-RS resource comprises CSI-RS antenna ports for all TRPs/RRHs, i.e., P=Σr=1N Pr, where P is the total number of antenna ports, and Pr is the number of antenna ports associated with r-th TRP. In this case, a TRP corresponds to (or maps to or is associated with) a group of antenna ports.
In one example, when the codebook is a new codebook (e.g., one of the two new codebooks above), then the CSIreporting is based on a CSI resource set comprising one or multiple NZP CSI-RS resource(s).
In the present disclosure, we use N, NTRP, NRRH interchangeably for a number of TRPs/RRHs.
In one embodiment, a UE is configured with higher layer parameter codebookType set to e.g., ‘typeII-r18-cjt’ for CJT from multiple TRPs as described in this disclosure. A bit-map parameter ‘typeII-RI-Restriction-r18’ is used to indicate which RI or rank value is not allowed to be reported. For example, the bit-map parameter ‘typeII-RI-Restriction-r18’ forms the bit sequence t3, t2, t1, t0 where t0 is the LSB and t3 is the MSB. When ti is zero, i∈{0, 1, . . . , 3}, RI reporting is not allowed to correspond to any precoder associated with v=i+1 layers. In one example, the bit-map parameter ‘typeII-RI-Restriction-r18’ is TRP-common (or TRP-group common), i.e., one common RI value for all TRPs. In one example, the bit-map parameter ‘typeII-RI-Restriction-r18’ is TRP-specific (or TRP-group specific), i.e., one RI value for each TRP.
In one embodiment, a UE is configured with higher layer parameter codebookType set to e.g., ‘typeII-r18-cjt’ for CJT from multiple TRPs as described in this disclosure. For each TRP r=1, . . . , NTRP (or TRP group), a bit-map parameter ‘n1-n2-codebookSubsetRestriction-r18’ is used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups.
In one example, for each TRP r=1, . . . , NTRP (or TRP group), the bit-map parameter ‘n1-n2-codebookSubsetRestriction-r18’ forms the bit sequence Br=B1,rB2,r and configures the vector group indices g(k,r) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). Bits b2,r(k,2(N
where kl,i+pL,f,r(3)∈{0,1} is part of the bitmap indicator for TRP r, and indicates whether the corresponding coefficient is zero (when bit value=0) or non-zero (when bit value=1), pl,p,r(1) is a (first) reference amplitude, and pl,i+pL,f,r(2) is a (second) differential amplitude coefficient, as described in 5.2.2.2.5 of TS 38.214.
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2,r(k,2(N
In one example, the higher-layer parameter ‘n1-n2-codebookSubsetRestriction-r18’, a joint parameter indicating N1, N2, and codebook subset restrictions is TRP-specific, i.e., one parameter ‘n1-n2-codebookSubsetRestriction-r18’ for each TRP. One example for the TRP-specific higher-layer parameter ‘n1-n2-codebookSubsetRestriction-r18’ can be as follows.
In another example, the parameter ‘n1-n2-codebookSubsetRestriction-r18-trp’ is replaced with ‘n1-n2-codebookSubsetRestriction-r18-SP’ (where SP stands for single panel) in the above example, which can be described as follows:
In another example, the parameter can be described in a structured way as a sequence of multiple restrictions (e.g., one for each TRP), which can be described as follows:
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one embodiment, a UE is configured with a codebook restriction as described herein except that there is a restriction on the configured value of (N1, N2). For example, the value of (N1, N2) is restricted to be the same pair for all TRPs.
In one example, each configured ‘n1-n2-codebookSubsetRestriction-r18’ is such that N1 and N2 values are the same for all TRPs.
In one example, the length (number of bits) for each n1-n2-codebookSubsetRestriction-r18 is the same for all TRPs.
In one example, the choice of each n1-n2-codebookSubsetRestriction-r18 is the same for all TRPs, for example, each corresponds to two-one, two-two, four-two, . . . or sixteen-one.
In one embodiment, a UE is configured with a codebook restriction as described herein except that only hard amplitude restriction is allowed to configure (not allowing to configure soft amplitude restriction), where the hard amplitude restriction refers that its associated amplitudes can be either restricted to all 0 or no restricted, (hence freely selected using the configured codebook).
For example, it is not allowed to configure b2,r(k,2(N
In another example, there is no such a table since the hard restriction allows to configure either its associated amplitudes to be 0 or under no restriction (hence no equation on γi+pL). For example, a higher-layer parameter to indicate the hard restriction can be according to the following: bit ‘0’ corresponds to its associated amplitudes to be 0, and bit ‘1’ corresponds to it associated amplitudes having no restriction.
In another example, it is allowed to configure b2,r(k,2(N
In one example, for each example of higher-layer parameters (RRC signaling, or information elements) shown herein, the size of bit string can be computed based on 2-bits for B2,r (instead of 4-bits for B2,r).
In one example, the parameter can be described in a structured way as a sequence of multiple restrictions (e.g., one for each TRP), which can be described as follows:
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, each example on higher-layer parameters described herein can be extended, similarly, with replacing the following:
by the following:
As shown in the example above, the bit width for B2,r is changed from 2N1N2×4 to 2N1N2×2, and the bit width for B1,r is maintained as 11 bits for N2>1 or 0 bits for N2=1.
In one embodiment, a UE is configured with higher layer parameter codebookType set to, e.g., ‘typeII-r18-cjt’. Two high-layer parameters are used, one to configure N1, N2 values and another to configure codebook subset restrictions, respectively. For example, a first higher-layer parameter can be denoted as ‘n1-n2’ and a second higher-layer parameter can be denoted as ‘codebookSubsetRestriction-r18’.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same/common value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups. For each TRP r=1, . . . , NTRP (or TRP group), the bit-map parameter ‘codebookSubsetRestriction-r18’ forms the bit sequence Br=B1,rB2,r and configures the vector group indices g(k,r) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). Bits b2,r(k,2(N
where kl,i+pL,f,r(3)∈{0,1} is part of the bitmap indicator for TRP r, and indicates whether the corresponding coefficient is zero (when bit value=0) or non-zero (when bit value=1), pl,p,r(1) is a (first) reference amplitude, and pl,i+pL,f,r(2) is a (second) differential amplitude coefficient, as described in 5.2.2.2.5 of TS 38.214.
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2,r(k,2(N
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, it is the same example as example as described herein except that only hard amplitude restriction is allowed to configure (not allowing to configure soft amplitude restriction), where the hard amplitude restriction refers that its associated amplitudes can be either restricted to all 0 or no restricted, (hence freely selected using the configured codebook).
For example, it is not allowed to configure b2,r(k,2(N
In another example, there is no such a table since the hard restriction allows to configure either its associated amplitudes to be 0 or under no restriction (hence no equation on γi+pL,r). For example, a higher-layer parameter to indicate the hard restriction can be according to the following: bit ‘0’ corresponds to its associated amplitudes to be 0, and bit ‘1’ corresponds to it associated amplitudes having no restriction.
In another example, it is allowed to configure b2,r(k,2(N
In one example, for each example of higher-layer parameters (RRC signaling, or information elements) shown herein, the size of bit string can be computed based on 2-bits for B2,r (instead of 4-bits for B2,r).
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
As shown in the example above, the bit width for B2,r is changed from 2N1N2×4 to 2N1N2×2, and the bit width for B1,r is maintained as 11 bits for N2>1 or 0 bits for N2=1.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups. The bit-map parameter ‘codebookSubsetRestriction-r18’ forms the bit sequence Br=B1B2,r for each TRP r=1, . . . , NTRP (or TRP group), but the vector group indices g(k) are common for all TRPs, i.e., one g(k) for all TRPs (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). Bits b2,r(k,2(N
where kl,i+pL,f,r(3)∈{0,1} is part of the bitmap indicator for TRP r, and indicates whether the corresponding coefficient is zero (when bit value=0) or non-zero (when bit value=1), pl,p,r(1) is a (first) reference amplitude, and pl,i+pL,f,r(2) is a (second) differential amplitude coefficient, as described in 5.2.2.2.5 of TS 38.214.
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2,r(k,2(N
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups. For each TRP r=1, . . . , NTRP (or TRP group), the bit-map parameter ‘codebookSubsetRestriction-r18’ forms the bit sequence Br=B1,rB2, and the vector group indices g(k,r) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). Bits b2,r(k,2(N
where kl,i+pL,f,r(3)∈{0,1} is part of the bitmap indicator for TRP r, and indicates whether the corresponding coefficient is zero (when bit value=0) or non-zero (when bit value=1), pl,p,r(1) is a (first) reference amplitude, and pl,i+pL,f,r(2) is a (second) differential amplitude coefficient, as described in 5.2.2.2.5 of TS 38.214.
In another example, the average coefficient amplitude associated with the vectors in groups g(k,r) for ∀r over CSI-RS resources (TRPs) is less than or equal to γi+pL. One example is as follows:
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2(k,2(N
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, it is the same example as herein except that only hard amplitude restriction is allowed to configure (not allowing to configure soft amplitude restriction), where the hard amplitude restriction refers that its associated amplitudes can be either restricted to all 0 or no restricted, (hence freely selected using the configured codebook).
For example, it is not allowed to configure b2(k,2(N
In another example, there is no such a table since the hard restriction allows to configure either its associated amplitudes to be 0 or under no restriction (hence no equation on γi+pL,r) For example, a higher-layer parameter to indicate the hard restriction can be according to the following: bit ‘0’ corresponds to its associated amplitudes to be 0, and bit ‘1’ corresponds to it associated amplitudes having no restriction.
In another example, it is allowed to configure b2(k,2(N
In one example, for each example of higher-layer parameters (RRC signaling, or information elements) shown herein, the size of bit string can be computed based on 2-bits for B2 (instead of 4-bits for B2).
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
As shown in the example above, the bit width for B2 is changed from 2N1N2×4 to 2N1N2×2, and the bit width for B1,r is maintained as 11 bits for N2>1 or 0 bits for N2=1.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups. The bit-map parameter ‘codebookSubsetRestriction-r18’ forms the bit sequence B=B1B2, and the vector group indices g(k) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]) and is TRP-common, i.e., the same value for all TRPs. Bits b2(k,2(N
where kl,i+pL,f,r(3)∈{0,1} is part of the bitmap indicator for TRP r, and indicates whether the corresponding coefficient is zero (when bit value=0) or non-zero (when bit value=1), pl,p,r(1) is a (first) reference amplitude, and pl,i+pL,f,r(2) is a (second) differential amplitude coefficient, as described in 5.2.2.2.5 of TS 38.214.
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2(k,2(N
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups only. For each TRP r=1, . . . , NTRP (or TRP group), the bit-map parameter ‘codebookSubsetRestriction-r18’ forms the bit sequence B1,r, and configures the vector group indices g(k,r) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). In other words, there is no amplitude restriction, i.e., no B2 is defined.
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In another example, the higher-layer parameters ‘n1-n2’ and ‘codebookSubsetRestriction-r18’ can be as follows.
In one embodiment, a UE is configured with higher layer parameter codebookType set to, e.g., ‘typeII-r18-cjt’. Two high-layer parameters are used, one to configure N1, N2 values and another to configure codebook subset restrictions, respectively. For example, a first higher-layer parameter can be denoted as ‘n1-n2’ and a second higher-layer parameter can be denoted as ‘codebookSubsetRestriction-r18’. Here, ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP.
In one example, the higher-layer parameter ‘n1-n2’ can be as follows. The other higher-layer parameter ‘codebookSubsetRestriction-r18’ can be according to one of the examples shown herein.
In one example, the higher-layer parameter ‘n1-n2’ can be as follows. The other higher-layer parameter ‘codebookSubsetRestriction-r18’ can be according to one of the examples shown herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups and (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘codebookSubsetRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the details as described herein.
In one embodiment, a UE is configured with higher layer parameter codebookType set to, e.g., ‘typeII-r18-cjt’. Three high-layer parameters are used to configure (N1, N2), vector group restriction, and coefficient amplitude restriction, respectively. For example, a first higher-layer parameter can be denoted as ‘n1-n2’, a second higher-layer parameter can be denoted as ‘vectorGroupRestriction-r18’, and a third higher-layer parameter can be denoted as ‘amplitudeRestriction-r18’, respectively.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups. For each TRP r=1, . . . , NTRP (or TRP group), the bit-map parameter ‘vectorGroupRestriction-r18’ forms the bit sequence B1,r, and configures the vector group indices g(k,r) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). The bit-map parameter ‘amplitudeRestriction-r18’ forms the bit sequence B2,r for each TRP r=1, . . . , NTRP (or TRP group). Bits b2,r(k,2(N
where kl,i+pL,f,r(3)∈{0,1} is part of the bitmap indicator for TRP r, and indicates whether the corresponding coefficient is zero (when bit value=0) or non-zero (when bit value=1), pl,p,r(1) is a (first) reference amplitude, and pl,i+pL,f,r(2) is a (second) differential amplitude coefficient, as described in 5.2.2.2.5 of TS 38.214.
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2,r(k,2(N
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, it is the same example as herein except that only hard amplitude restriction is allowed to configure (not allowing to configure soft amplitude restriction), where the hard amplitude restriction refers that its associated amplitudes can be either restricted to all 0 or no restricted, (hence freely selected using the configured codebook).
For example, it is not allowed to configure b2,r(k,2(N
In another example, there is no such a table since the hard restriction allows to configure either its associated amplitudes to be 0 or under no restriction. For example, a higher-layer parameter to indicate the hard restriction can be according to the following: bit ‘0’ corresponds to its associated amplitudes to be 0, and bit ‘1’ corresponds to it associated amplitudes having no restriction.
In another example, it is allowed to configure b2,r(k,2(N
In one example, for each example of higher-layer parameters (RRC signaling, or information elements) shown herein, the size of bit string can be computed based on 2-bits for B2,r (instead of 4-bits for B2,r).
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
As shown in the example above, the bit width for B2,r is changed from 2N1N2×4 to 2N1N2×2, and the bit width for B1,r is maintained as 11 bits for N2>1 or 0 bits for N2=1.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups. The bit-map parameter ‘vectorGroupRestriction-r18’ forms the bit sequence B1 and configures the vector group indices g(k) common for all TRPs, i.e., one value for all TRPs (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). The bit-map parameter ‘amplitudeRestriction-r18’ forms the bit sequence B2,r for each TRP r=1, . . . , NTRP (or TRP group). Bits b2,r(k,2(N
where kl,i+pL,f,r(3)∈{0,1} is part of the bitmap indicator for TRP r, and indicates whether the corresponding coefficient is zero (when bit value=0) or non-zero (when bit value=1), pl,p,r(1) is a (first) reference amplitude, and pl,i+pL,f,r(2) is a (second) differential amplitude coefficient, as described in 5.2.2.2.5 of TS 38.214.
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2,r(k,2(N
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups. For each TRP r=1, . . . , NTRP (or TRP group), the bit-map parameter ‘vectorGroupRestriction-r18’ forms the bit sequence B1,r and configures the vector group indices g(k,r) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). The bit-map parameter ‘amplitudeRestriction-r18’ forms the bit sequence B2 common for all TRPs, i.e., one value for all TRPs. Bits b2(k,2(N
In another example, the average coefficient amplitude associated with the vectors in groups g(k,r) for ∀r over CSI-RS resources (TRPs) is less than or equal to γi+pL. One example is as follows:
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2(k,2(N
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, it is the same example as herein except that only hard amplitude restriction is allowed to configure (not allowing to configure soft amplitude restriction), where the hard amplitude restriction refers that its associated amplitudes can be either restricted to all 0 or no restricted, (hence freely selected using the configured codebook).
For example, it is not allowed to configure b2(k,2(N
In another example, there is no such a table since the hard restriction allows to configure either its associated amplitudes to be 0 or under no restriction. For example, a higher-layer parameter to indicate the hard restriction can be according to the following: bit ‘0’ corresponds to its associated amplitudes to be 0, and bit ‘1’ corresponds to it associated amplitudes having no restriction.
In another example, it is allowed to configure b2(k,2(N
In one example, for each example of higher-layer parameters (RRC signaling, or information elements) shown herein, the size of bit string can be computed based on 2-bits for B2 (instead of 4-bits for B2).
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’ and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
As shown in the example above, the bit width for B2 is changed from 2N1N2×4 to 2N1N2×2, and the bit width for B1,r is maintained as 11 bits for N2>1 or 0 bits for N2=1.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups. The bit-map parameter ‘vectorGroupRestriction-r18’ forms the bit sequence B1 and configures the vector group indices g(k) common for all TRPs, i.e., one value for all TRPs (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]). The bit-map parameter ‘amplitudeRestriction-r18’ forms the bit sequence B2 common for all TRPs, i.e., one value for all TRPs. Bits b2(k,2(N
For example, a UE that does not report the parameter ‘softAmpRestriction-r18’=‘supported’ in its capability signaling is not expected to be configured with b2(k,2(N
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the first parameter ‘n1-n2’ is TRP-common (or TRP-group common), i.e., the same value of (N1, N2) for all TRPs is configured with the first parameter. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups. For each TRP r=1, . . . , NTRP (or TRP group), the bit-map parameter ‘vectorGroupRestriction-r18’ forms the bit sequence B1,r and configures the vector group indices g(k,r) (similar to as in clause 5.2.2.2.3 of TS 38.214 [9]).
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
Other terminology can be used for ‘maxNrofSPs’ in the example. For example, maxNrofPortGroups can be used.
In one example, ‘maxNrofSPs’ can be defined as ‘INTEGER:=x’, where x=2, 3, or 4.
In one example, the higher-layer parameters ‘n1-n2’, ‘vectorGroupRestriction-r18’, and ‘amplitudeRestriction-r18’ can be as follows.
In one embodiment, a UE is configured with higher layer parameter codebookType set to, e.g., ‘typeII-r18-cjt’. Three high-layer parameters are used to configure (N1, N2), vector group restriction, and coefficient amplitude restriction, respectively. For example, a first higher-layer parameter can be denoted as ‘n1-n2’, a second higher-layer parameter can be denoted as ‘vectorGroupRestriction-r18’, and a third higher-layer parameter can be denoted as ‘amplitudeRestriction-r18’, respectively. Here, ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP.
In one example, the higher-layer parameter ‘n1-n2’ can be as follows. The other higher-layer parameters ‘vectorGroupRestriction-r18’ and ‘amplitudeRestriction-r18’ can be according to one of the examples shown herein.
In one example, the higher-layer parameter ‘n1-n2’ can be as follows. The other higher-layer parameters ‘vectorGroupRestriction-r18’ and ‘amplitudeRestriction-r18’ can be according to one of the examples shown herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the third higher-layer parameter ‘amplitudeRestriction-r18’ is a bit-map parameter used to indicate restriction on (average) coefficient amplitudes associated with the vectors in the groups, the details as described herein.
In one example, the first parameter ‘n1-n2’ is TRP-specific, i.e., the value of (N1, N2) is configured for each TRP, details as above. The second higher-layer parameter ‘vectorGroupRestriction-r18’ is a bit-map parameter used to indicate restrictions on vector groups, and the details as described herein.
In one embodiment, or NTRP=1, a UE can be configured with a first scheme among the schemes described in embodiments described herein, and, for NTRP>1, the UE can be configured with a second scheme among the schemes described herein. In addition, the same rank restriction is applied across NTRP CSI-RS resources.
In one example, the first scheme is a scheme for (CSI-RS-resource-specific) vector group restriction and (CSI-RS-resource-specific) soft amplitude restriction such as one of the examples described herein.
In one example, the second scheme is a scheme for CSI-RS-resource-specific vector group restriction and CSI-RS-resource-specific) hard amplitude restriction such as one of the examples described herein.
In one example, (the first scheme, the second scheme) can be according to at least one of the following examples.
In one embodiment, a UE can be configured with codebook subset restriction according to at least one of the examples described in embodiments described herein. In addition, a UE is further configured with a higher-layer parameter for CSI-RS-resource-specific CBSR turning-off operation, where the CSI-RS-resource-specific CBSR turning-off operation refers to an operation that can be configured for turning off/on the CBSR per CSI-RS resource. In addition, the same rank restriction is applied across NTRP CSI-RS resources.
In one example, at least one of the NTRP configured CSI-RS resources is configured with CBSR, and remaining configured CSI-RS resources can be optionally configured with CBSR, i.e. the remaining CSI-RS resources can be configured with CBSR or can be configured without CBSR.
In one example, one of the NTRP configured CSI-RS resources is always configured with CBSR, and remaining (NTRP−1) configured CSI-RS resources can be optionally configured with CBSR.
In one example, CSI-RS-resource-specific vector group restriction and CSI-RS-resource-specific hard amplitude restriction are allowed to configure for the CSI-RS resources that are configured with CBSR. For example, CSI-RS-resource-specific vector group restriction and CSI-RS-resource-specific hard amplitude restriction described in examples/embodiments described herein can be configured for the CSI-RS resources that are configured with CBSR.
In one embodiment, for any embodiment/example shown in disclosure, there is at least one of NTRP CSI-RS resources regarding CBSR with the field having Optional, Need S.
In one example, on the following parameter (or corresponding parameter as shown in each example of this disclosure), “n1-n2-codebookSubsetRestriction” is the number of antenna ports in first (n1) and second (n2) dimension and codebook subset restriction (see TS 38.214 [19] clause 5.2.2.2.3). Also, the number of bits for codebook subset restriction is CEIL(log 2(nchoosek(O1*O2,4)))+8*n1*n2 where nchoosek(a,b)=a!/(b!(a−b)!). This is according to the following example: if the field is absent, the UE will assume that the UE is not configured with any codebook subset restriction for the corresponding CSI-RS resource. The UE will also assume that (N1,N2) value for this CSI-RS resource is the same as that for a CSI-RS resource for which this field is present (configured/provided) in the associated CSI-ReportConfig. This field is present (configured/provided) for at least one of Ntrp CSI-RS resources in the associated CSI-ReportConfig.
In one example, the parameter (or corresponding parameter as shown in each example of this disclosure), “n1-n2-codebookSubsetRestriction” is shown as follows:
In another example, the parameter (or corresponding parameter as shown in each example of this disclosure), “n1-n2-codebookSubsetRestriction” is shown as follows:
The method begins with the UE receiving information about a CSI report associated with NTRP>1 groups of antenna ports (1010). For example, in 1010, the information indicates (i) a CJT codebook, (ii) a rank restriction, and (iii) NTRP CBSRs. The UE then identifies a set S1 of one or more rank values allowed for the CSI report (1020). For example, in 1020, the UE identifies the set S1 based on the rank restriction.
The UE then identifies sets S2,1, . . . , S2,N
The UE then determines the CSI report associated with the NTRP groups of antenna ports (1040). For example, in 1040, the CSI report is determined based on the CJT codebook, the set S1, and the sets S2,1, . . . , S2,N
In one or more embodiments, the information includes information about NTRP NZP CSI-RS resources each associated with one of the NTRP groups of antenna ports, the UE is measures the NTRP NZP CSI-RS resources, and the CSI report is determined based on the measurement.
In one or more embodiments, the rank restriction indicates a set of restricted rank values that are not allowed for the CSI report and the CBSRs indicate a set of SD basis vectors that are not allowed for the CSI report.
In one or more embodiments, the rank restriction corresponds to a bit sequence r=r3r2r1r0, and when ri is zero for i∈{0, 1, . . . , 3}, information associated with a rank value of i+1 is not allowed for the CSI report.
In one or more embodiments, the CBSRs correspond to a bit sequence Bn=B1,nB2,n for each antenna group n=1, . . . , NTRP, where: B1,n is used to indicate restriction on SD vector groups for each antenna group n=1, . . . , NTRP and B2,n is used to indicate restriction on SD vectors in each of the SD vector groups for each antenna group n=1, . . . , NTRP.
In one or more embodiments, B1,n is a bit sequence indicating four SD vector groups among O1O2 SD vector groups, where Oj is an oversampling factor associated with length-N1 discrete Fourier transform (DFT) vectors for j-th antenna port dimension, j∈{1,2}, and the four SD vector groups are allowed for the CSI report.
In one or more embodiments, B2,n is a bit sequence, where every two-bits of B2,n either having ‘00’ or ‘11’ indicates each of the SD vectors either not allowed or allowed for the CSI report.
In one or more embodiments, B2,n is a bit sequence, where each bit of B2,n either having ‘0’ or ‘1’ indicates each of the SD vectors either not allowed or allowed for the CSI report.
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 figures illustrate different examples of user equipment, various changes may be made to the figures. For example, the user equipment can include any number of each component in any suitable arrangement. In general, the figures do not limit the scope of this disclosure to any particular configuration(s). Moreover, while figures illustrate operational environments in which various user equipment features disclosed in this patent document can be used, these features can be used in any other suitable system.
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. 63/352,918 filed on Jun. 16, 2022, U.S. Provisional Patent Application No. 63/459,121 filed on Apr. 13, 2023, U.S. Provisional Patent Application No. 63/459,901 filed on Apr. 17, 2023, U.S. Provisional Patent Application No. 63/461,116 filed on Apr. 21, 2023. and U.S. Provisional Patent Application No. 63/471,435 filed on Jun. 6, 2023. The above-identified provisional patent applications are hereby incorporated by reference in their entirety.
Number | Date | Country | |
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63352918 | Jun 2022 | US | |
63459121 | Apr 2023 | US | |
63459901 | Apr 2023 | US | |
63461116 | Apr 2023 | US | |
63471435 | Jun 2023 | US |