Systems and methods for near-field multiple input multiple output multiple rank codebooks

Abstract

Systems and methods for near-field multiple input multiple output (MIMO) multiple rank codebooks are discussed. A user equipment (UE) performs a measurement of a channel state information reference signal (CSI-RS) received from a base station; generates, based on the measurement, a precoder matrix indicator (PMI) that indicates a multiple-rank precoder W that is based on a W 1 matrix that uses selected beam vector(s) across different polarizations of an antenna array of a transmission reception point (TRP) of the base station, where the beam vector(s) are selected according to uniform planar array (UPA) response calculation(s) that rely on quantization mechanisms that operate over azimuth(s) of the UE, elevation(s) of the UE, and distance(s) of the UE relative to / from one or more antenna element(s) of the antenna array; and sends, to the base station, channel state information (CSI) feedback comprising the PMI. Corresponding network-side functionalities are also described.

Description

SYSTEMS AND METHODS FOR NEAR-FIELD MULTIPLE INPUT MULTIPLE OUTPUT MULTIPLE RANK CODEBOOKSTECHNICAL FIELD

[0001] This application relates generally to wireless communication systems, including wireless communication systems using codebook-based channel state information (CSI) feedback mechanisms.BACKGROUND

[0002] Wireless mobile communication technology uses various standards and protocols to transmit data between a base station and a wireless communication device. Wireless communication system standards and protocols can include, for example, 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) (e.g., 4G), 3GPP New Radio (NR) (e.g., 5G), and Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard for Wireless Local Area Networks (WLAN) (commonly known to industry groups as Wi-Fi®).

[0003] As contemplated by the 3GPP, different wireless communication systems' standards and protocols can use various radio access networks (RANs) for communicating between a base station of the RAN (which may also sometimes be referred to generally as a RAN node, a network node, or simply a node) and a wireless communication device known as a user equipment (UE). 3GPP RANs can include, for example. Global System for Mobile communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE) RAN (GERAN). Universal Terrestrial Radio Access Network (UTRAN), Evolved Universal Terrestrial Radio Access Network (E-UTRAN), and / or Next-Generation Radio Access Network (NG-RAN).

[0004] Each RAN may use one or more radio access technologies (RATs) to perform communication between the base station and the UE. For example, the GERAN implements GSM and / or EDGE RAT, the UTRAN implements Universal Mobile Telecommunication System (UMTS) RAT or other 3GPP RAT, the E-UTRAN implements LTE RAT (sometimes simply referred to as LTE). and NG-RAN implements NR RAT (sometimes referred to herein as 5G RAT, 5GNR RAT, or simply NR). In certain deployments, the E-UTRAN may also implement NR RAT. In certain deployments, NG-RAN may also implement LTE RAT.14907-1288-3843\1 P70336WO1

[0005] A base station used by a RAN may correspond to that RAN. One example of an E-UTRAN base station is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (also commonly denoted as evolved Node B, enhanced Node B, eNodeB, or eNB). One example of an NG-RAN base station is a next generation Node B (also sometimes referred to as a g Node B or gNB).

[0006] A RAN provides its communication services with external entities through its connection to a core network (CN). For example, E-UTRAN may utilize an Evolved Packet Core (EPC) while NG-RAN may utilize a 5G Core Network (5GC).

[0007] Frequency bands for 5G NR may be separated into two or more different frequency ranges. For example, Frequency Range 1 (FR1) may include frequency bands operating in sub-6 gigahertz (GHz) frequencies, some of which are bands that may be used by previous standards, and may potentially be extended to cover new spectrum offerings from 410 megahertz (MHz) to 7125 MHz. Frequency Range 2 (FR2) may include frequency bands from 24.25 GHz to 52.6 GHz. Note that in some systems, FR2 may also include frequency bands from 52.6 GHz to 71 GHz (or beyond). Bands in the millimeter wave (mmWave) range of FR2 may have smaller coverage but potentially higher available bandwidth than bands in FR1. Skilled persons will recognize these frequency ranges, which are provided by way of example, may change from time to time or from region to region.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0008] To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced.

[0009] FIG. 1 illustrates a diagram for the use of a CJT codebook.

[0010] FIG. 2 illustrates a diagram illustrating an embodiment for the division of an antenna array into a plurality of virtual antenna panels for purposes of reducing an effective range of a near-field for the antenna array.

[0011] FIG. 3 illustrates a diagram for example panel selection indications as may be used when using CJT codebooks with virtual antenna panels of an antenna array.

[0012] FIG. 4 illustrates a diagram for an example of a port selection indication as may be used when using CJT codebooks with virtual antenna panels of an antenna array.24907-1288-3843\1 P70336WO1

[0013] FIG. 5 illustrates a diagram for the use of a CJT codebook that accounts for the use of multiple virtual antenna panels.

[0014] FIG. 6 illustrates a diagram of an antenna array and a UE.

[0015] FIG. 7 illustrates a diagram showing various clusters of a TRP that correspond to different beam vectors.

[0016] FIG. 8 illustrates a diagram of an antenna array that is used by a TRP to communicate with a UE.

[0017] FIG. 9 illustrates a method of a UE, according to embodiments discussed herein.

[0018] FIG. 10 illustrates a method of a base station, according to embodiments discussed herein.

[0019] FIG. 11 illustrates an example architecture of a wireless communication system, according to embodiments disclosed herein.

[0020] FIG. 12 illustrates a system for performing signaling between a wireless device and a network device, according to embodiments disclosed herein.DETAILED DESCRIPTION

[0021] Various embodiments are described with regard to a UE. However, reference to a UE is merely provided for illustrative purposes. The example embodiments may be utilized with any electronic component that may establish a connection to a network and is configured with the hardware, software, and / or firmware to exchange information and data with the network. Therefore, the UE as described herein is used to represent any appropriate electronic component.

[0022] Frequency range 3 (FR3) (ranging from 7~14 gigahertz (GHz)) is under consideration as useable spectrum (e.g., for new / upcoming RATs, such as 6G RAT). It is observed preliminarily that cell site reuse within FR1 leads to using a number of antenna elements / ports at a transmission reception point (TRP) of a base station (e g., with an aperture at 1.5 meters). It is also noted that near-field effects can be experienced by UEs in wireless communication systems in some cases.

[0023] Note that some solutions for channel state information (CSI) feedback when operating in FR3 use discrete Fourier transform (DFT) basis-based solutions by exploiting sub-division and a coherent j oint transmission (CJT) codebook.34907-1288-3843\1 P70336WO1

[0024] Non-DFT basis-based solutions for CSI feedback are attractive in that they have the potential for low CSI feedback overhead and good performance. Further, non-DFT basis-based solutions allow for distance-based frequency reuse and / or location division multiple access (LDMA). Accordingly, embodiments herein relate systems and methods for multiple rank non-DFT basis-based CSI designs (e.g., for use in FR3 operation).

[0025] FIG. 1 illustrates a diagram 100 for the use of a CJT codebook. As illustrated, a central scheduler 102 schedules 114 each of the first TRP 104, the second TRP 106, the third TRP 108, and the fourth TRP 110 to perform a CJT 116 to the UE 112, where each of the first TRP 104, the second TRP 106, the third TRP 108, and the fourth TRP 110 simultaneously transmit to the UE 112 signaling that corresponds to a same codeword or codewords.

[0026] In various wireless communication systems, the use of DFT bases for spatial beams results in relatively simplified handling of transitions between a near-field propagation case and a far-field propagation case that may be called-for due to UE mobility. However, it is possible to consider new spatial beam bases (e.g., non-DFT bases) for aspects related to the handling of near-field CSI feedback as well.

[0027] FIG. 2 illustrates a diagram 200 illustrating an embodiment for the division of an antenna array 202 into a plurality of virtual antenna panels for purposes of reducing an effective range of a near-field for the antenna array 202. The antenna array 202 may be used by the TRP 204 to communicate with the UE 206. As illustrated, the antenna array 202 is made up of various individual cross-polarized antenna elements. Note that herein, polarizations corresponding to such a cross-polarization may be referred to as a “first polarization” and a “second polarization.”

[0028] A Rayleigh distance (DRayieigh) that delineates the near-field for the antenna array 202 and the far-field of the antenna array 202 will be understood to be calculable generally as2D2DRayieigh "A?where.D is an applicable antenna aperture of the antenna array 202; andis an applicable wavelength (e.g., of a carrier being used to communicate between the TRP 204 and the UE 206).44907-1288-3843\1 P70336WO1As illustrated, the overall antenna array 202 has an aperture 216. It is noted that, according to the above calculation, if an applicable antenna aperture D is reduced, a Rayleigh distance DRayieigh for the antenna reduces rapidly (on an exponential basis).

[0029] The diagram 200 illustrates that the antenna array 202 can be sub-divided into the first virtual antenna panel 208, the second virtual antenna panel 210, the third virtual antenna panel 212, and the fourth virtual antenna panel 214. It may be that these virtual antenna panels are schedulable on a CJT basis (e.g., with reference back to FIG. 1, the schedulability7and behavior of the first virtual antenna panel 208 may be considered analogous to that of the first TRP 104, the schedulability and behavior of the second virtual antenna panel 210 may be analogous to that of the second TRP 106. etc.)

[0030] As illustrated, the aperture 216 of the antenna array 202 is larger than any aperture associated within any one of the virtual antenna panels (FIG. 2 explicitly illustrates the aperture 218 of the first virtual antenna panel 208 for comparison purposes). Accordingly, when sub-dividing the antenna array into the virtual antenna panels and using CJT across the virtual antenna panels, a first DRayieigh 220 that corresponds to the entire TRP antenna array 202 (within which near-field CSI mechanisms may be called for) is effectively reduced to a second DRayieigh 222 corresponding to the reduced size of the virtual antenna panels. This reduction occurs because of the smaller aperture D of the individual virtual antenna panels.

[0031] This means that when leveraging CJT across the (relatively smaller) virtual antenna panels, all UEs that are outside of the second DRayieigh 222 (even ones that are within the first DRayieigh 220) can appropriately use corresponding CSI mechanisms that assume CJT across the smaller virtual antenna panels, as the curved wavefront generated by the CJT use is understood to be piece-wise linearized in the region outside of second DRayieigh 222. A CJT codebook may accordingly be arranged for use the virtual antenna panels for communicating with UEs that are within the near-field of the overall antenna array 202 (within the first DRayieigh 220) but outside the second DRayieigh 222.

[0032] Note that such a CJT codebook may be of particular use in FR3 cases, because the relatively higher frequencies thereof (ranging from, e.g., 7~14 GHz) correspond to relatively small wavelengths k. Accordingly, were the TRP 204 to operate in these higher frequencies without using CJT across virtual antenna panels as described, the applicable first DRayieigh 220 / the near-field region that corresponds to the entire aperture 216 across the entire antenna array 202 has the potential to cover an appreciable physical54907-1288-3843\1 P70336WO1extent of the cell. Through the use of a CJT codebook and virtual antenna panels as described, the first DRayieigh 220 effectively reduces to the second DRayieigh 222 when CJT is used, and operations for UEs within the first DRayieigh 220 but without the second DRayieigh 222 are given corresponding definition. Note that FIG. 2 is not drawn to scale, and that for FR3 cases, second DRayieigh 222 may be very close indeed to the TRP 204.

[0033] As one example, take a case of operation at 14 gigahertz (GHz) where an applicable antenna array aperture is two meters and where a virtual antenna array aperture associated with that antenna array is 0.5 meters. In such a case, the applicable DRayieigh across the entire antenna panel calculates at around 373.6 meters, while the DRayieigh applicable across the smaller virtual antenna panel calculates at around 23.3 meters.

[0034] Within such cases, spatial non-stationarity of a UE can be accounted for in the network deployment. It is observed that CJT codebooks for the virtual antenna panels can be configured to select active / inactive virtual antenna panels of an antenna array for such purposes.

[0035] FIG. 3 illustrates a diagram 300 for example panel selection indications 302 as may be used when using CJT codebooks with virtual antenna panels of an antenna array. FIG. 3 assumes the antenna array 202 of the TRP 204 that communicates with the UE 206 and that is sub-divided into the first virtual antenna panel 208, the second virtual antenna panel 210, the third virtual antenna panel 212, and the fourth virtual antenna panel 214 as is described elsewhere herein in relation to FIG. 2.

[0036] As illustrated, the panel selection indications 302 indicate that the first virtual antenna panel 208, the third virtual antenna panel 212, and the fourth virtual antenna panel 214 are used (corresponding to indications of ‘1’ in the panel selection indications 302), while the second virtual antenna panel 210 is not to be used to communicate with the UE 206 (corresponding to the indication ‘0’ in the panel selection indications 302). Accordingly, the diagram 300 illustrates that the antenna elements of the second virtual antenna panel 210 are unused 304.

[0037] FIG. 4 illustrates a diagram 400 for an example of a port selection indication 402 as may be used when using CJT codebooks with virtual antenna panels of an antenna array. FIG. 4 assumes the antenna array 202 of the TRP 204 that communicates with the UE 206 and that is sub-divided into the first virtual antenna panel 208, the second virtual64907-1288-3843\1 P70336WO1antenna panel 210, the third virtual antenna panel 212, and the fourth virtual antenna panel 214 as is described elsewhere herein in relation to FIG. 2.

[0038] To provide a fine level of control on which antenna ports / antenna elements are disabled in the precoding, a blocking pattern can be considered for use. The port selection indication 402 represents a selected blocking pattern, which may be applied to a Type II CSI codebook, with the result that various antenna elements of the antenna array 202 are unused 404, as illustrated.

[0039] Mechanisms for when and / or how to conduct sub-division within an antenna array may be considered for purposes of adaptability of / between near-field region and far-field regions, and / or for different shapes of blocking objects (e.g., to account for spatial non-stationarity of a UE). Accordingly, the use of sub-division is appropriate for responding to near-field problems stemming from a perspective of the entire overall antenna array.

[0040] FIG. 5 illustrates a diagram 500 for the use of a CJT codebook that accounts for the use of multiple virtual antenna panels. The diagram 500 illustrates that the codebook contains first codebook entries 502 for a first TRP or first virtual antenna panel 504 and second codebook entries 506 for a second TRP or second virtual antenna panel 508. Entries from the codebook are selected based on delay tap index and doppler shift index. Each entry corresponds to a spatial beam index. Note that, as illustrated, the entries used for the first TRP or first virtual antenna panel 504 may correspond to first spatial beam indexes 514 for first delay tap indexes 510 and first doppler shift indexes 512, while the entries used for the second TRP or second virtual antenna panel 508 may correspond to second spatial beam indexes 520 that correspond to second delay tap indexes 516 and second doppler shift indexes 518. Note that the second spatial beam indexes 520 may be (but are not required to be) different than the first spatial beam indexes 514. Thus, different spatial beams may be used at each of the TRPs / each of the antenna panels (as the case may be) corresponding to any given sets of delay tap index and doppler shift index.

[0041] Accordingly, it will be understood that CSI (e.g., predictive CSI) frameworks may be built for use (e.g., in FR3) that represent a combined solution for both multi-TRP cases and / multi-virtual-antenna-panel and Doppler domain cases corresponding to a transmission from a single overall antenna array at a single TRP.74907-1288-3843\1 P70336WO1

[0042] Corresponding to such CJT codebooks that account for the potential use of virtual antenna panels, correlation among the virtual antenna panels can be exploited in order to reduce CSI feedback overhead in cases where virtual antenna panels are in use.

[0043] Note that while FIG. 5 illustrates two sets of codebook entries that are arranged according to two TRP / virtual antenna panel sets, it will be understood that a codebook could include any number of such sets corresponding to any number of TRP / virtual antenna panel sets.

[0044] FIG. 6 illustrates a diagram 600 of an antenna array 602 and a UE 604. As illustrated, the antenna array 602 includes (among other things) the first antenna element 606 (denoted < So,o in FIG. 6) and a second antenna element 608 (denoted Sm,nin FIG. 6).

[0045] A piece-wise linearization of a wavefront can be understood mathematically by considering / taking into account the distance difference between the first antenna element 606 and the second antenna element 608. As illustrated in the diagram 600, the antenna array 602 is assumed to be in an x-z plane in space. Further, relative to the center of the antenna array 602 / the first antenna element 606, an applicable azimuth angle of the UE 604 is denoted 0, while an applicable elevation angle of the UE 604 is denoted < / >.

[0046] In this arrangement, the location of the UE 604 (denoted r in FIG. 6) can be related as r = (r cos 6 sin (j>, r sin 6 sin (j>, r cos ). Further, note that the location of any (m. / 7)-th antenna element of the antenna array 602 (for example, the second antenna element 608) can be understood as (n * dx, 0, m * dz), where dxis an antenna element spacing used along the x-axis and dzis an antenna element spacing used along the z-axis.

[0047] Within this framework, the distance r(x,z) = ||Smn— r|| (or, equivalently, r(x,z) = | |r — Sm„| |) between an (m,n)-th antenna element of the antenna array 602 and the UE 604 can be approximated according to:

[0048] Further, after accounting for constant phase aspects, relationships for related x-axis and z-axis phase components described in terms of n and m can be derived as:— ndxxcos 6 sin < / > +n cos 6sinfor the x-axis. and2r, m2dz(sin2<b~)— md7cos ® -I - - - - for the z-axis.z2r84907-1288-3843\1 P70336WO1

[0049] Accordingly, an overall near-field array response vector for the antenna array 602 in terms of r, < / >. and 0 (SLUPA(T, < / >, 0)) is:auPA^>(P>r) —ax(^< >r) ®az( >r), where:- - [ax(6,< / >, r)]„ = ex*2r. andr [ -az(< / >,r)]m= e7N2*2-r

[0050] Refer generally to “Near-Field Communications: A Tutorial Review,” Yuanwei Liu et al., IEEE Open Journal of the Communications Society, Date of Publication 16 August 2023, Digital Object Identifier: 10.1109 / OJCOMS.2023.3305583. Note with higher order Taylor expansion, more accurate approximation to | |r — Sm n11) can be achieved, which may involve additional term(s) affected by both m and n, for the phase differences in the azimuth domain and in the vertical domain.

[0051] Note that herein, a calculation of an auPA(r, <f), 3) may be referred to as a uniform planar array (UPA) response calculation.

[0052] Embodiments herein relate to the arrangement and use of distance-dependent multi-rank CSI feedback codebooks (for example, in terms of the use of CJT across multiple virtual antenna panels) that leverage this underlying mathematical framework. Contents of such codebooks may be understood in terms of estimated parameters for r, (j>, and 9 within this mathematical framework.

[0053] Note that embodiments herein may rely on some assumptions. Preliminarily, it may be assumed that each relevant location on an antenna array (e.g., an (m, n) location on an antenna array) represents a placement of a pair of cross-polarized antennas on the antenna panel. Further, antenna ports may be arranged according to polarizations as may be defined for, e.g., certain existing 3GPP wireless communication systems.

[0054] Finally, note that codebooks discussed herein may track, in form, a W-JW precoder formation / framework as understood in, for example, some 3GPP wireless communication systems. For example, precoders W selected using codebooks discussed herein may be understandable in terms of a combination of, loosely speaking, a “longterm” or “wideband” characteristics matrix Wi and a “short-term” (and potentially frequency-dependent) matrix W2 as these are understood in, for example, 3 GPP-based NR wireless communication system implementations.94907-1288-3843\1 P70336WO1

[0055] Mechanisms for codebook construction that leverage a W1 / W2 formulation are now discussed. A first example corresponding to a rank 2 case may use:where bi is a beam vector calculated according to a UPA response calculation AUPA ', < / >, 9) as discussed herein. The values of r,G used for the b determination according to am4(r, G) may be understood in relation to a position of a UE relative to a given antenna element of the antenna array. As illustrated, the b\ beam vector is used for each of a first polarization (the first row of ffi) and a second polarization (the second row of Wi).

[0056] The applicable UPA response calculation aup r, G) may be understood to be carried out according to a quantization mechanism over / for one or more “raw” values of r, (j>, and / or G for the UE to arrive at correspondingly quantized values of r, (j>, G that are ultimately actually used / represented in the applicable UPA response calculation HUPA(T,, G). Various possible embodiments for this quantization mechanism are now described.

[0057] In a first option for the quantization mechanism, each of the “raw” values for r,, and G are individually quantized into one of a set of expected values. In such cases, a “raw” value for G is quantized into some value GQ,Xsuch that G E {GQ, I, GO, 2,.... }. Further, a “raw” value for is quantized into some valuesuch that G {^2,1, ^g.2,..., }. Finally, a “raw” value for r is quantized into some value rg,xsuch that r E {ry,i, ro,2,..., }.

[0058] In a second option for the quantization mechanism, a joint quantization may be used across the and G domains. For example, the “raw” values of j> and G may (taken together) map to a first value within a set of defined values defined for this purpose. In some examples, the set of defined values may be. for example, a set of values as may be in use corresponding to some Type I or Type II CSI codebook implementations used in some 3GPP-based wireless communication systems. Corresponding to these second option cases, the quantization mechanism may also separately treat a “raw” value for r by quantizing it into some value rp.x such that r E {ro,i, r< Q_2,

[0059] In a third option for the quantization mechanism, a joint quantization may be used across all of the, G, and r domains. In such cases, the “raw” values of, G, and r may be taken together and analyzed on a set-wise basis such that a pre-determined set of104907-1288-3843\1 P70336WO1quantized values θQ,x, φQ,x, and rQ,xthat are representative of a desired UPA response calculation aUPA(r, φ, θ) are identified. In other words, (θ, φ, r) ∈ {(θQ,1, φQ,1, rQ,1), (θQ,2, φQ,2, rQ,2), . . . }.

[0060] Note that for embodiments corresponding this first example for codebook construction, various options for the W2 matrix are also contemplated. In a first alternative, the W2 matrix is a wideband matrix.

[0061] In a second alternative, the W2 matrix is a sub-band matrix like a 3GPP Release 15 Type II matrix or a 3GPP Release 16 eType II matrix (that explores frequency correlations).

[0062] In a third alternative, the W matrix is a sub-band matrix like a 3GPP Type I matrix.

[0063] A second example for codebook construction that leverages a W1 / W2 formulation and that can be used to support up to a rank 4 case may use:[bi, b2] 0W0 [bi, b2]_ ’where b\ and Z>2 are each beam vectors calculated according to a UPA response calculation aUPA(r, φ, θ) as discussed herein. The values of r, 0, 9 used for the bi determination may be denoted n, ^i, 9i. Accordingly, a corresponding UPA response calculation according to aUPA(r1, φ1, θ1) for b\ may be understood in relation to a position of a UE relative to a first antenna element of the antenna array. Further, the values of r, 0, 9 used for the 62 determination may be denoted r2, φ2, θ2. Accordingly, a corresponding UPA response calculation aUPA(r2, φ2, θ2) for X may be understood in relation to the same UE’s position relative to a second (different) antenna element of the antenna array. As illustrated, each of the b\ beam vector and the X beam vector are used for each of a first polarization (the first row of the W matrix) and a second polarization (the second row of the W1matrix).

[0064] Note that the second example, the W\ matrix has 4 columns, and thus is good for use up to rank 4 cases. The ultimate rank of the overall precoder will also depend on the number of columns in the W2 matrix.

[0065] Note that, from the TRP perspective, it may be that the beam vectors b\ and X are understood to correspond to different clusters used by a (same, single) TRP. FIG. 7 illustrates a diagram 700 showing various clusters of a TRP 702 that correspond to114907-1288-3843\1 P70336WO1different beam vectors. The diagram 700 illustrates that the TRP 702 uses (at least) three clusters, the first cluster 704. the second cluster 706, and the third cluster 708. Each of these clusters corresponds to a different general spatial direction. By way of example, the diagram 700 indicates specifically the directionality 710 of the first cluster 704, and it will be noted that other directionalities are illustrated for the second cluster 706 and the third cluster 708. Note that the directionalities used in each cluster may apply with respect to all sub-bands in use. These clusters may be understood to correspond to individual beam vectors.

[0066] Further, each cluster may be made up of one or more narrow beams. By way of example, the diagram 700 indicates specifically that the first cluster 704 uses the four narrow beams 712, and it will be noted that the other clusters also use sets of narrow beams analogously. These narrow beams may be understood to correspond to different beam vectors for the given cluster.

[0067] The applicable UPA response calculations aUPA(r, φ, θ) may be understood to be carried out according to a quantization mechanism over / for one or more “raw” values of r, φ, and / or θ for the UE to arrive at correspondingly quantized values of r, φ, θ that are ultimately actually used / represented in the applicable UPA response calculations aUPA(r, φ, θ). The quantization mechanism may be, for example, any of the example quantization mechanisms for r, φ, and / or θ that are described elsewhere herein.

[0068] Note that for embodiments corresponding this second example for codebook construction, various options for the W matrix are also contemplated. In a first alternative, the W2 matrix is a wideband matrix.

[0069] In a second alternative, the W2 matrix is a sub-band matrix like a 3GPP Release 15 Type II matrix or a 3GPP Release 16 eType II matrix (that explores frequency correlations).

[0070] In a third alternative, the W2 matrix is a sub-band matrix like a 3GPP Type I matrix.

[0071] Note that in some cases, constraints on usable values of φ1, φ2, θ1, and θ2(e.g., due to physical interdependencies for these values due to antenna element spacing) may be enforced.

[0072] The construction / use of both beam vectors bi and b2 corresponds to a recognition that there can be cases where there are multiple dominant angles of departure124907-1288-3843\1 P70336WO1(AoDs) that are used to communicate with a UE, the wireless channel tends to support the use of higher (multiple) ranks.

[0073] Note that while the second example relates a case for the use of two beam vectors (e.g., bi and b2,) this is given by way of example and not by way of limitation. It may be that additional beam vectors (e.g., more than two) may be used (e.g., such that even higher ranks are sufficiently supported). For example, in some cases, three beam vectors (bi, bi, and bi) may be used. In other examples, four beam vectors (bi, bi, bi, and bi) may be used. In some such cases, up to rank 8 may be supported. Note that even with the case of four beam vectors (bi, bi, bi. and bi), these may still be used in rank 1-7 precoder construction (depending on the choice of the Wi matrix).

[0074] A third example for codebook construction that leverages a W1 / W formulation is now discussed. FIG. 8 illustrates a diagram 800 of an antenna array 802 that is used by a TRP (not illustrated) to communicate with a UE 808. As shown, the antenna array 802 is sub-divided into a first virtual antenna panel 804 and a second virtual antenna panel 806. Embodiments corresponding to the third example may assume the use of the antenna array 802 and the sub-division as just described.

[0075] The third example can be used to support up to a rank 4 case and may use:[bi,b2] 0 0 0 - 0 [ / Ji,fe2] 0 00 0 [bnb2] 00 0 0 [b1(b2].where b\ and b2are each beam vectors calculated according to a UPA response calculation aUPA-panel(r, φ, θ). In embodiments corresponding to the third example, the aUPA-panel(r, φ, θ) is determined on a per-virtual-antenna-panel basis (rather than on the basis of the entire antenna array 802). For example, the values of r, φ, θ used for the b1determination may be denoted r1, φ1, θ1. These values may represent their corresponding physical metrics for the UE as determined in relation to the individual first virtual antenna panel 804 (rather than over the entire antenna array 802). Accordingly, a corresponding UPA response calculation according to aUPA-panel(r1, φ1, θ1) for bi may be understood in relation to a UE’s positioning relative to a first antenna element of the first virtual antenna panel 804. Further, the values of r,9 used for the bi determination may be denoted r2, φ2, θ2. These values may represent their corresponding physical metrics for the UE as determined in relation to the individual second virtual antenna panel 806134907-1288-3843\1 P70336WO1(rather than over the entire antenna array 802). Accordingly, a corresponding UPA response calculation aUPA-panel(r2, φ2, θ2) for 62 may be understood in relation to the same UE’s positioning relative to an antenna element of the second virtual antenna panel 806.

[0076] As illustrated, each of the b beam vector and the 62 beam vector are used for a first polarization at the first virtual antenna panel 804 (the first row of the W\ matrix) and the second virtual antenna panel 806 (the second row of the Wi matrix). Further, each of the bi beam vector and the 62 beam vector are used for a second polarization at the first virtual antenna panel 804 (the third row of the Wi matrix) and the second virtual antenna panel 806 (the fourth row of the Wi matrix).

[0077] Note that for embodiments corresponding this third example for codebook construction, various options for the Wz matrix are also contemplated. In a first alternative, the W2 matrix is a wideband matrix.

[0078] In a second alternative, the Wz matrix is a sub-band matrix like a 3GPP Release 15 Type II matrix or a 3GPP Release 16 eType II matrix (that explores frequency correlations).

[0079] In a third alternative, the W2 matrix is a sub-band matrix like a 3GPP Type I matrix.

[0080] Note that in some cases, constraints on usable values of φ1, φ2, θ1, and θ2(e.g., due to physical interdependencies for these values due to antenna element spacing) may be enforced.

[0081] The construction / use of both beam vectors b and 62 corresponds to a recognition that there can be cases where there are multiple dominant AoDs that are used to communicate with a UE, the wireless channel tends to support the use of higher (multiple) ranks.

[0082] Note that while the third example relates a case for the use of two beam vectors (e.g., bi and >2,) this is given by way of example and not by way of limitation. It may be that additional beam vectors (e.g., more than two) may be used (e.g., such that even higher ranks are sufficiently supported). For example, in some cases, three beam vectors (Z>i, / ?2, and Z>3) may be used. In other examples, four beam vectors (6>i, Z>2, Z>3, and bl may be used. In some such cases, transmissions up to rank 8 may be supported. Note that even with the case of four beam vectors (b\, bz, b-}, and 64), these may still be used in rank 1-7 precoder construction (depending on the choice of the Wz matrix).144907-1288-3843\1 P70336WO1

[0083] A fourth example for codebook construction that leverages a W1 / W2formulation is now discussed. The description of this fourth example again assumes the use of the antenna array 802 and the sub-division into the first virtual antenna panel 804 and the second virtual antenna panel 806 as illustrated in FIG. 8.

[0084] The fourth example can be used to support up to a rank 4 case and may use:[bi,b2] 0 0 0 -w_ 0 [b'-i / b'z] 0 010 0 [b1;b2] 0. 0 0 0 [b'^b'z].where bi and bz are each beam vectors calculated according to a UPA response calculation auPA-Panei(r, < / >, 0) in the manner discussed elsewhere herein in relation to the third example.

[0085] The fourth example differs from the third example in that beam vectors b 1 and b ’2 are used in the W\ matrix corresponding to the second virtual antenna panel 806. For example, as illustrated, each of the bi beam vector and the bz beam vector are used for a first polarization at the first virtual antenna panel 804 (the first row of the Wi matrix), while each of the b beam vector and the b ’2 beam vector is used for the first polarization at the second virtual antenna panel 806 (the second row of the Wi matrix). Further, each of the bi beam vector and the bz beam vector are used for a second polarization at the first virtual antenna panel 804 (the third row of the Wi matrix), while each of the b ’1 beam vector and the b ’2beam vector are used for the second polarization at the second virtual antenna panel 806 (the fourth row of the Wi matrix).

[0086] The b ’1 beam vector and the b ’2 beam vector for the second virtual antenna panel 806 may be beam vectors that are based on the bi beam vector and the b2beam vector but that have been modified to account for small angle differences between the first virtual antenna panel 804 and the second virtual antenna panel 806.

[0087] Note that for embodiments corresponding this fourth example for codebook construction, various options for the W2 matrix are also contemplated. In a first alternative, the Wz matrix is a wideband matrix.

[0088] In a second alternative, the Wz matrix is a sub-band matrix like a 3GPP Release 15 Type II matrix or a 3GPP Release 16 eType II matrix (that explores frequency correlations).154907-1288-3843\1 P70336WO1

[0089] In a third alternative, the W2 matrix is a sub-band matrix like a 3GPP Type I matrix.

[0090] Note that in some cases, constraints on usable values of φ1, φ2, θ1, and θ2(e.g., due to physical interdependencies for these values due to antenna element spacing) may be enforced.

[0091] The construction / use of both beam vectors bi and 62 corresponds to a recognition that there can be cases where there are multiple dominant AoDs that are used to communicate with a UE. the wireless channel tends to support the use of higher (multiple) ranks.

[0092] Note that while the second example relates a case for the use of two beam vectors (e.g., bi and >2) and modified versions of the same (e.g.. b 1 and b ’2). this is given by way of example and not by way of limitation. It may be that additional beam vectors (e.g., more than two) may be used (e.g., such that even higher ranks are sufficiently supported). For example, in some cases, three beam vectors (bi, b2, and ) and correspondingly modified beam vectors (b 1, b ’2, and b 3) may be used. In other examples, four beam vectors (bi. 62, 63, and b ) and correspondingly modified beam vectors (b ’1, b ’2, b ’3, and b ’4) may be used. In some such cases, transmissions up to rank 8 may be supported. Note that even with the case of four beam vectors (bi,, bs, and Zu), these may still be used in rank 1-7 precoder construction (depending on the choice of the W2 matrix).

[0093] Note that the principle for the use of modified beam vectors and the manners described in this fourth example can be analogously applied in cases for a lower rank transmission than that illustrated in this example (e.g., rank 1 and rank 2 cases) in order to account for small angle differences between virtual antenna panels in those cases as well.

[0094] Further aspects as may be applicable with respect to embodiments discussed herein (e.g., embodiments according to the first option, the second option, the third option, and or the fourth option as discussed herein) are now discussed.

[0095] In some implementations, if distance-dependent basis vectors / spatial beams (e.g., as in b\ and 62, etc., as described herein) cannot be successfully or reliably identified, it may be beneficial to fall back to the use of DFT basis vectors / spatial beams.

[0096] In some cases, it may be beneficial to include the DFT basis vectors in the overall set of basis vectors (e.g., vectors corresponding to an effective r = co) in164907-1288-3843\1 P70336WO1codebooks as described herein. In one mechanism, this can be understood in terms of adding a quantization option for the effective r = co case into options for the quantization mechanisms that are discussed herein.

[0097] For example, in the first option or the second option for a quantization mechanism, a “raw” value for r mapping to an effective r = co case (e.g., when the UE in the far-field) may be quantized into some particular value rQ,xwithin r ∈ {rQ,1, rQ,2, . . . , } that represents / corresponds to the effective r = co case.

[0098] Further, in the third option for a quantization mechanism, a “raw” value for r mapping to an effective r = co case may limit the selection of a determined set of jointly quantized valuesQQ. X, and rQ,xaccording to (θ, φ, r) ∈{(θQ,1, φQ,1, rQ,1), (θQ,2, φQ,2, rQ,2), . . . } to those sets that use an rQ,xthat represents / corresponds to the effective r = ∞ case (e g., when the UE in the far-field).

[0099] Corresponding to various embodiments, if a same spatial beam is to be assumed for near-field cases corresponding to different polarizations, then a spatial beam selection similar to polarization common selection in NR Type II / eType II codebooks can be reused.

[0100] However, in cases where spatial beams are independently determined for each polarization, then a polarization independent selection mechanism may be used.

[0101] Note that with respect to network implementation, different network vendors may choose different antenna spacings (dz, dx), and this antenna spacing information is typically not made public in a cellular network deployment.

[0102] Corresponding to embodiments herein, an overall near-field array response vector for the antenna array in terms of r, (j>, and 0 (auPA(r, <j>, 6*)) may be represented as:aUPA(θ,φ,r) = ax(θ,φ,r) ⊗ az(φ,r), where:n2dx2(1−cos2θsin2φ)[ax(0, 0,r)]„ _e~J~ (~ndx cos 9 sin <j> and−j(2π / λ)(−mdzcosφ+m2dz2(sin2φ)cos φ[a^ (0, ^)]m 2rThis can be reformulated as:= ax(β1,β2) ⊗ az(β3,β4), where:174907-1288-3843\1 P70336WO1β1= (dxcos θ sin φ / λ),β2= dx2(1−cos2θsin2φ)β3= (dzcos φ / λ),β4= dz2(sin2φ)E4“ 2rA ‘[ax(β1, β2)]n= e−j2π(−nβ+nβ)and[az(β3, β4)]m= e−j2π(−mβ+mβ)

[0103] From a CSI feedback design perspective, it is enough to feed back(β1, β2, β3, β4) to the network so the network can construct the desired vector. Thus, it will be understood that for each feedback design formulated for (r, φ, θ), there is a counterpart formulatedwith Further, when there are multiple vectors such as aUPA-panel(r1, φ1, θ1) and aUPA-panel(r2, φ2, θ2), etc., in a precoder construction, there are corresponding parameter sets (β1,1, β2,1, β3,1, β4,1), (β1,2, β2,2, β3,2, β4,2), ■■■, etc.

[0104] In general, quantized values of β1, β2, β3, β4) (or some subset of those parameters) are carried in the feedback from UE to network.

[0105] It can be seen that the feedback of indication for quantized values of β1and β3can be enabled by feedback design for DFT bases, e.g., in NR Type I or Type II codebook designs. Instead of feeding back β2and β4, an indication for quantized value(s) of β2and / or β4which are both dependent on r may be carried in the feedback from the UE to the network. The design options discussed herein regarding (θ, φ, r) largely apply to (β1, β2, β3, β4).

[0106] In some cases, the Kronecker product approximation may not be accurate enough andaUPA(β1, β2, β3, β4) = (ax(β1, β2) ⊗ az(β3, β4)) ⊙ axz(β5) may be used, where:⊙ is for element-wise multiplication between two matrices (ax(β1, β2) ⊗ az(β3, β4)) and (axz(β5)), and184907-1288-3843\1 P70336WO1[axz(β5)]n,m= e−j2π(mnβ), according to / ? S)-

[0107] An indication for quantized value(s) ofand / or β4and / or β5which are all dependent on r may be carried in the feedback from the UE to the network.

[0108] LDMA may be understood corresponding to a distance dependent term in the spatial basis, and may be indicated by the UE to the network. Then, UEs can be paired together if they share the same / a similar location, or as they are at different locations that correspond to fortunate combinations (e.g., where their mutual interference is reduced) and thus are a good pair of UE candidates for UE co-scheduling purposes (notwithstanding their differing locations).

[0109] For multi user multiple input multiple output (MU-MIMO) scheduling, a distance-dependent interference (along a same general direction) may be provided as an interference measurement resource (IMR) to the UE. Then, for multiple co-scheduled UEs, each of their interference characteristics can be represented by different IMRs. A UE of interest can select the most appropriate IMR for co-scheduling purposes.

[0110] Corresponding to CSI measurement in such cases, it may be that one channel measurement resource (CMR) may be used (e.g., a single CMR resource is assumed); otherwise, a channel state information reference signal (CSI-RS) resource indicator (CRI) can also be considered. Further, multiple IMRs may be used (e.g., a first IMR (IMR-1) for a first co-scheduled UE (UE-A), a second IMR (IMR-2) for a second coscheduled UE (UE-B), etc.)

[0111] Corresponding to CSI reporting in such cases, it may be that (CRI)Zrank indicator (RI) / precoder matrix indicator (PMI) / channel quality index (CQI) (and optionally an IMR selection) is provided in the reporting. In a first such example where UE-A’s interference is represented by IMR-1 and UE-B’s interference is represented by IMR-2, in one transmission time interval (TTI), a UE of interest finds that UE-A is a good candidate for UE co-scheduling; accordingly, IMR-1 ’s index / signaling is reported. Further, in another TTI. the UE of interest finds that UE-B a good candidate for UE coscheduling; accordingly, IMR-2’s index / signaling is reported.

[0112] With respect to some cases using codeword searching, it may be that R represents a wideband covariance matrix that is formed similar to an NR type II codeword search case. For example:194907-1288-3843 1 P70336WO1«11where R̃ = R11+ R2221Then, it may be assumed that a number of codewords is limited (e.g., to around 4000 (assuming 128 ports / polarization) * an oversampling factor (e.g. 4) * a number (e.g.. 4) of distances). However, as the corresponding basis vectors are not necessarily orthogonal, ensuring that a proposed algorithm works well can use further checking.

[0113] An algorithm that accounts for the potentiality that basis vectors are not necessarily orthogonal is proposed:1. First, it is assumed / taken that R̃ = R11+ R22, B = [].2. Then, a beam is identified using MAXb∈CbHR̃b and B «- B U {&}.3. Then, R is projected to the null space of B or b (for iterative processing purposes): P = I − bbH, R̃ ← PR̃P.4. Finally, steps 2 and 3 above are repeated until a desired number of beams b is found.

[0114] With respect to some cases involving polar codebook searching, it is noted that an exhaustive search of a polar codebook incurs more overhead compared to a search of a conventional angular codebook. It has been determined that this searching complexity may be improved through the use of multi-phase beam sweeping / channel estimation, as follows:1. First, angle-domain beam sweeping (e.g., beams) is performed. This step may use a far-field DFT codebook.2. Then, distance-domain beam sweeping (e.g., beams) is performed after an angle has been determined. This procedure may use a near-field polar codebook.

[0115] This procedure may reduce overhead / complexity of a search of the polar codebook from O(MN) to O(kM + N) (where k is understood as a scalar corresponding to overhead for step 2 in the case that multiple angles are selected in step 1). Note that additional improvement to such cases through the establishment / definition of a hierarchical codebook (e.g., the use of a hierarchical codebook in the angular domain and an exhaustive search in distance domain) are contemplated.

[0116] FIG. 9 illustrates a method 900 of a UE, according to embodiments discussed herein. The method 900 includes performing 902 performs a measurement of a CSI-RS received from a base station. The method 900 further includes generating 904, based on204907-1288-3843\1 P70336WO1the measurement, a PMI that indicates a multiple-rank precoder W that is based on a W1 matrix that uses a first beam vector for each of a first polarization and a second polarization of an antenna array of a TRP the base station, wherein the first beam vector is a result of a first UPA calculation that uses a quantization mechanism over a first azimuth of the UE relative to a first antenna element of the antenna array, a first elevation of the UE relative to the first antenna element, and a first distance of the UE from the first antenna element. The method 900 further includes sending 906, to the base station, CSI feedback comprising the PMI.

[0117] In some embodiments of the method 900, the quantization mechanism over the first azimuth, the first elevation, and the first distance generates: a quantized azimuth of the UE relative to the first antenna element; a quantized elevation of the UE relative to the first antenna element; and a quantized distance of the UE from the first antenna element; and the quantized azimuth, the quantized elevation, and the quantized distance are used in the first UPA response calculation. In some such embodiments, the quantization mechanism generates information about the quantized azimuth, the quantized elevation, and the quantized distance jointly.

[0118] In some embodiments of the method 900, the quantization mechanism over the first azimuth, the first elevation, and the first distance generates: a joint quantization of the first azimuth and the first elevation that maps to a first value of a set of defined values; and a quantized distance of the UE from the first antenna element; and the first value and the quantized distance are used in the first UPA response calculation.

[0119] In some embodiments of the method 900, the first beam vector comprises a DFT beam vector.

[0120] In some embodiments of the method 900, the W1 matrix uses the first beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array.

[0121] In some embodiments, the method 900 further includes determining a modified first beam vector based on the first beam vector and a relative positioning of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array; and the W1 matrix uses the first beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and the214907-1288-3843\1 P70336WO1modified first beam vector for each of the first polarization and the second polarization across the second virtual antenna panel.

[0122] In some embodiments of the method 900, the W1 matrix further uses a second beam vector for each of the first polarization and the second polarization of the antenna array, wherein the second beam vector is a result of a second UPA response calculation that is different than the result of the first UPA response calculation. In some such embodiments, the W1 matrix uses the first beam vector and the second beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array. In some such embodiments, the method 900 further includes determining a modified first beam vector based on the first beam vector and a relative positioning of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array; and determining a modified second beam vector based on the second beam vector and the relative positioning of the first virtual antenna panel and the second virtual antenna panel; wherein: the W1 matrix uses the first beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and the modified first beam vector for each of the first polarization and the second polarization across the second virtual antenna panel; and the W1 matrix uses the second beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and the modified second beam vector for each of the first polarization and the second polarization across the second virtual antenna panel.

[0123] In some embodiments, the method 900 further includes performing a first interference measurement on a first IMR and a second interference measurement on the second IMR; and determining, based on a comparison of the first interference measurement and the second interference measurement, that the first IMR corresponds to expected higher spectral efficiency at the UE than the second IMR; wherein the CSI feedback further comprises an indication of the first IMR.

[0124] In some embodiments of the method 900, the multiple-rank precoder W is further based on a W2 matrix that makes a wideband indication corresponding to the W1 matrix.

[0125] In some embodiments of the method 900, the multiple-rank precoder W is further based on a W2 matrix that makes a plurality of different sub-band indications corresponding to the W1 matrix.224907-1288-3843\1 P70336WO1

[0126] FIG. 10 illustrates a method 1000 of a base station, according to embodiments discussed herein. The method 1000 includes sending 1002, to a UE, a CSI-RS. The method 1000 further includes receiving 1004, from the UE, CSI feedback comprising a PMI that indicates a multiple-rank precoder W that is based on a W matrix that uses a first beam vector for each of a first polarization and a second polarization of an antenna array of a TRP of the base station, wherein the first beam vector is a result of a first UPA calculation that uses a quantization mechanism over a first azimuth of the UE relative to a first antenna element of the antenna array, a first elevation of the UE relative to the first antenna element, and a first distance of the UE from the first antenna element. The method 1000 further includes precoding 1006 a downlink (DL) transmission to the UE using the multiple-rank precoder W.

[0127] In some embodiments of the method 1000, the quantization mechanism over the first azimuth, the first elevation, and the first distance generates: a quantized azimuth of the UE relative to the first antenna element; a quantized elevation of the UE relative to the first antenna element; and a quantized distance of the UE from the first antenna element; and the quantized azimuth, the quantized elevation, and the quantized distance are used in the first UPA response calculation. In some such embodiments, the quantization mechanism generates information about the quantized azimuth, the quantized elevation, and the quantized distance jointly.

[0128] In some embodiments of the method 1000, the quantization mechanism over the first azimuth, the first elevation, and the first distance generates: a joint quantization of the first azimuth and the first elevation that maps to a first value of a set of defined values; and a quantized distance of the UE from the first antenna element; and the first value and the quantized distance are used in the first UPA response calculation.

[0129] In some embodiments of the method 1000, the first beam vector comprises a DFT beam vector.

[0130] In some embodiments of the method 1000, the Wi matrix uses the first beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array.

[0131] In some embodiments of the method 1000, the W\ matrix uses the first beam vector for each of the first polarization and the second polarization across a first virtual antenna panel of the antenna array and a modified first beam vector for each of the first234907-1288-3843\1 P70336WO1polarization and the second polarization across a second virtual antenna panel of the antenna array; wherein the modified first beam vector is based on the first beam vector and a relative positioning of the first virtual antenna panel the second virtual antenna panel.

[0132] In some embodiments of the method 1000. the W1 matrix further uses a second beam vector for each of the first polarization and the second polarization of the antenna array, wherein the second beam vector is a result of a second UPA response calculation that is different than the first UPA response calculation. In some such embodiments, the W1 matrix uses the first beam vector and the second beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array. In some such embodiments, the W1 matrix uses the first beam vector for each of the first polarization and the second polarization across a first virtual antenna panel of the antenna array and a modified first beam vector for each of the first polarization and the second polarization across a second virtual antenna panel of the antenna array, wherein the modified first beam vector is based on the first beam vector and a relative positioning of the first virtual antenna panel the second virtual antenna panel; and the W1 matrix uses the second beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and a modified second beam vector for each of the first polarization and the second polarization across the second virtual antenna panel, wherein the modified second beam vector is based on the second beam vector and the relative positioning of the first virtual antenna panel and the second virtual antenna panel.

[0133] In some embodiments of the method 1000, the CSI feedback further comprises an indication of an IMR.

[0134] In some embodiments of the method 1000, the multiple-rank precoder W is further based on a W2 matrix that makes a wideband indication corresponding to the W1 matrix.

[0135] In some embodiments of the method 1000, the multiple-rank precoder W is further based on a W2 matrix that makes a plurality of different sub-band indications corresponding to the W1 matrix.

[0136] FIG. 11 illustrates an example architecture of a wireless communication system 1100, according to embodiments disclosed herein. The following description is provided for an example wireless communication system 1100 that operates in conjunction with244907-1288-3843\1 P70336WO1the LTE system standards and / or 5G or NR system standards as provided by 3GPP technical specifications.

[0137] As shown by FIG. 11, the wireless communication system 1100 includes UE 1102 and UE 1104 (although any number of UEs may be used). In this example, the UE 1102 and the UE 1104 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks), but may also comprise any mobile or non-mobile computing device configured for wireless communication.

[0138] The UE 1102 and UE 1104 may be configured to communicatively couple with a RAN 1106. In embodiments, the RAN 1106 may be NG-RAN, E-UTRAN, etc. The UE 1102 and UE 1104 utilize connections (or channels) (shown as connection 1108 and connection 1110, respectively) with the RAN 1106, each of which comprises a physical communications interface. The RAN 1106 can include one or more base stations (such as base station 1112 and base station 1114) that enable the connection 1108 and connection 1110.

[0139] In this example, the connection 1108 and connection 1110 are air interfaces to enable such communicative coupling, and may be consistent with RAT(s) used by the RAN 1106, such as, for example, an LTE and / or NR.

[0140] In some embodiments, the UE 1102 and UE 1104 may also directly exchange communication data via a sidelink interface 1116. The UE 1104 is shown to be configured to access an access point (shown as AP 1118) via connection 1120. By way of example, the connection 1120 can comprise a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, wherein the AP 1118 may comprise a Wi-Fi® router. In this example, the AP 1118 may be connected to another network (for example, the Internet) without going through a CN 1124.

[0141] In embodiments, the UE 1102 and UE 1104 can be configured to communicate using orthogonal frequency division multiplexing (OFDM) communication signals with each other or with the base station 1112 and / or the base station 1114 over a multicarrier communication channel in accordance with various communication techniques, such as, but not limited to, an orthogonal frequency division multiple access (OFDMA) communication technique (e.g., for downlink communications) or a single carrier frequency division multiple access (SC-FDMA) communication technique (e.g., for uplink and ProSe or sidelink communications), although the scope of the embodiments is254907-1288-3843\1 P70336WO1not limited in this respect. The OFDM signals can comprise a plurality of orthogonal subcarriers.

[0142] In some embodiments, all or parts of the base station 1112 or base station 1114 may be implemented as one or more software entities running on server computers as part of a virtual network. In addition, or in other embodiments, the base station 1112 or base station 1114 may be configured to communicate with one another via interface 1122. In embodiments where the wireless communication system 1100 is an LTE system (e.g., when the CN 1124 is an EPC), the interface 1122 may be an X2 interface. The X2 interface may be defined between two or more base stations (e.g., two or more eNBs and the like) that connect to an EPC, and / or between two eNBs connecting to the EPC. In embodiments where the wireless communication system 1100 is an NR system (e g., when CN 1124 is a 5GC), the interface 1122 may be an Xn interface. The Xn interface is defined between two or more base stations (e.g., two or more gNBs and the like) that connect to 5GC. between a base station 1112 (e.g., a gNB) connecting to 5GC and an eNB, and / or between two eNBs connecting to 5GC (e.g., CN 1124).

[0143] The RAN 1106 is shown to be communicatively coupled to the CN 1124. The CN 1124 may comprise one or more network elements 1126, which are configured to offer various data and telecommunications services to customers / subscribers (e.g., users of UE 1102 and UE 1104) who are connected to the CN 1124 via the RAN 1106. The components of the CN 1124 may be implemented in one physical device or separate physical devices including components to read and execute instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium).

[0144] In embodiments, the CN 1124 may be an EPC, and the RAN 1106 may be connected with the CN 1124 via an SI interface 1128. In embodiments, the SI interface 1128 may be split into two parts, an SI user plane (Sl-U) interface, which carries traffic data between the base station 1112 or base station 1114 and a serving gateway (S-GW), and the S1-MME interface, which is a signaling interface between the base station 1112 or base station 1114 and mobility’ management entities (MMEs).

[0145] In embodiments, the CN 1124 may be a 5GC, and the RAN 1106 may be connected with the CN 1124 via an NG interface 1128. In embodiments, the NG interface 1128 may be split into two parts, an NG user plane (NG-U) interface, which carries traffic data between the base station 1112 or base station 1114 and a user plane264907-1288-3843\1 P70336WO1function (UPF), and the SI control plane (NG-C) interface, which is a signaling interface between the base station 1112 or base station 1114 and access and mobility management functions (AMFs).

[0146] Generally, an application server 1130 may be an element offering applications that use internet protocol (IP) bearer resources with the CN 1124 (e.g., packet switched data services). The application server 1130 can also be configured to support one or more communication services (e.g., VoIP sessions, group communication sessions, etc.) for the UE 1102 and UE 1104 via the CN 1124. The application server 1130 may communicate with the CN 1124 through an IP communications interface 1132.

[0147] FIG. 12 illustrates a system 1200 for performing signaling 1234 between a wireless device 1202 and a network device 1218, according to embodiments disclosed herein. The system 1200 may be a portion of a wireless communications system as herein described. The wireless device 1202 may be, for example, a UE of a wireless communication system. The network device 1218 may be, for example, a base station (e.g., an eNB or a gNB) of a wireless communication system.

[0148] The wireless device 1202 may include one or more processor(s) 1204. The processor(s) 1204 may execute instructions such that various operations of the wireless device 1202 are performed, as described herein. The processor(s) 1204 may include one or more baseband processors implemented using, for example, a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

[0149] The wireless device 1202 may include a memory 1206. The memory 1206 may be a non-transitory computer-readable storage medium that stores instructions 1208 (which may include, for example, the instructions being executed by the processor(s) 1204). The instructions 1208 may also be referred to as program code or a computer program. The memory 1206 may also store data used by, and results computed by, the processor(s) 1204.

[0150] The wireless device 1202 may include one or more transceiver(s) 1210 that may include radio frequency (RF) transmitter circuitry and / or receiver circuitry that use the antenna(s) 1212 of the wireless device 1202 to facilitate signaling (e g., the signaling274907-1288-3843\1 P70336WO11234) to and / or from the wireless device 1202 with other devices (e.g., the network device 1218) according to corresponding RATs.

[0151] The wireless device 1202 may include one or more antenna(s) 1212 (e.g., one, two, four, or more). For embodiments with multiple antenna(s) 1212, the wireless device 1202 may leverage the spatial diversity of such multiple antenna(s) 1212 to send and / or receive multiple different data streams on the same time and frequency resources. This behavior may be referred to as, for example, multiple input multiple output (MIMO) behavior (referring to the multiple antennas used at each of a transmitting device and a receiving device that enable this aspect). MIMO transmissions by the wireless device 1202 may be accomplished according to precoding (or digital beamforming) that is applied at the wireless device 1202 that multiplexes the data streams across the antenna(s) 1212 according to known or assumed channel characteristics such that each data stream is received with an appropriate signal strength relative to other streams and at a desired location in the spatial domain (e.g., the location of a receiver associated with that data stream). Certain embodiments may use single user MIMO (SU-MIMO) methods (where the data streams are all directed to a single receiver) and / or MU-MIMO methods (where individual data streams may be directed to individual (different) receivers in different locations in the spatial domain).

[0152] In certain embodiments having multiple antennas, the wireless device 1202 may implement analog beamforming techniques, whereby phases of the signals sent by the antenna(s) 1212 are relatively adjusted such that the (joint) transmission of the antenna(s) 1212 can be directed (this is sometimes referred to as beam steering).

[0153] The wireless device 1202 may include one or more interface(s) 1214. The interface(s) 1214 may be used to provide input to or output from the wireless device 1202. For example, a wireless device 1202 that is a UE may include interface(s) 1214 such as microphones, speakers, a touchscreen, buttons, and the like in order to allow for input and / or output to the UE by a user of the UE. Other interfaces of such a UE may be made up of transmitters, receivers, and other circuitry (e.g., other than the transceiver(s) 1210 / antenna(s) 1212 already described) that allow for communication between the UE and other devices and may operate according to known protocols (e.g., Wi-Fi®, Bluetooth®, and the like).

[0154] The wireless device 1202 may include a near-field codebook module 1216. The near-field codebook module 1216 may be implemented via hardware, software, or284907-1288-3843\1 P70336WO1combinations thereof. For example, the near-field codebook module 1216 may be implemented as a processor, circuit, and / or instructions 1208 stored in the memory 1206 and executed by the processor(s) 1204. In some examples, the near-field codebook module 1216 may be integrated within the processor(s) 1204 and / or the transceiver(s) 1210. For example, the near-field codebook module 1216 may be implemented by a combination of software components (e.g., executed by a DSP or a general processor) and hardware components (e.g., logic gates and circuitry) within the processor(s) 1204 or the transceiver(s) 1210.

[0155] The near-field codebook module 1216 may be used for various aspects of the present disclosure, for example, aspects of FIG. 9. The near-field codebook module 1216 may configure the wireless device 1202 to perform a measurement of a CSI-RS received from a base station; generate, based on the measurement, a PMI that indicates a multiplerank precoder W that is based on a Wi matrix that uses a first beam vector for each of a first polarization and a second polarization of an antenna array of a TRP of the base station, wherein the first beam vector is a result of a first UPA response calculation that uses a quantization mechanism over a first azimuth of the UE relative to a first antenna element of the antenna array, a first elevation of the UE relative to the first antenna element, and a first distance of the UE from the first antenna element; and send, to the base station, CSI feedback comprising the PMI.

[0156] The network device 1218 may include one or more processor(s) 1220. The processor(s) 1220 may execute instructions such that various operations of the network device 1218 are performed, as described herein. The processor(s) 1220 may include one or more baseband processors implemented using, for example, a CPU, a DSP, an ASIC, a controller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

[0157] The network device 1218 may include a memory 1222. The memory 1222 may be a non-transitory computer-readable storage medium that stores instructions 1224 (which may include, for example, the instructions being executed by the processor(s) 1220). The instructions 1224 may also be referred to as program code or a computer program. The memory 1222 may also store data used by, and results computed by, the processor(s) 1220.

[0158] The network device 1218 may include one or more transceiver(s) 1226 that may include RF transmitter circuitry and / or receiver circuitry that use the antenna(s) 1228 of294907-1288-3843\1 P70336WO1the network device 1218 to facilitate signaling (e.g., the signaling 1234) to and / or from the network device 1218 with other devices (e.g.. the wireless device 1202) according to corresponding RATs.

[0159] The network device 1218 may include one or more antenna(s) 1228 (e g., one, two, four, or more). In embodiments having multiple antenna(s) 1228, the network device 1218 may perform MIMO, digital beamforming, analog beamforming, beam steering, etc., as has been described.

[0160] The network device 1218 may include one or more interface(s) 1230. The interface(s) 1230 may be used to provide input to or output from the network device 1218. For example, a network device 1218 that is a base station may include interface(s) 1230 made up of transmitters, receivers, and other circuitry (e.g., other than the trans ceiver(s) 1226 / antenna(s) 1228 already described) that enables the base station to communicate with other equipment in a core network, and / or that enables the base station to communicate with external networks, computers, databases, and the like for purposes of operations, administration, and maintenance of the base station or other equipment operably connected thereto.

[0161] The network device 1218 may include anear-field codebook module 1232. The near-field codebook module 1232 may be implemented via hardware, software, or combinations thereof. For example, the near-field codebook module 1232 may be implemented as a processor, circuit, and / or instructions 1224 stored in the memory 1222 and executed by the processor(s) 1220. In some examples, the near-field codebook module 1232 may be integrated within the processor(s) 1220 and / or the transceiver(s) 1226. For example, the near-field codebook module 1232 may be implemented by a combination of software components (e.g., executed by a DSP or a general processor) and hardware components (e.g., logic gates and circuitry) within the processor(s) 1220 or the transceiver(s) 1226.

[0162] The near-field codebook module 1232 may be used for various aspects of the present disclosure, for example, aspects of FIG. 10. The near-field codebook module 1232 may configured the network device 1218 to send, to a UE, a CSI-RS; receive, from the UE, CSI feedback comprising a PMI that indicates a multiple-rank precoder W that is based on a Wi matrix that uses a first beam vector for each of a first polarization and a second polarization of an antenna array of a TRP of the base station, wherein the first beam vector is a result of a first UPA response calculation that uses a quantization304907-1288-3843\1 P70336WO1mechanism over a first azimuth of the UE relative to a first antenna element of the antenna array, a first elevation of the UE relative to the first antenna element, and a first distance of the UE from the first antenna element; and; precode a DL transmission to the UE using the multiple-rank precoder W.

[0163] Embodiments contemplated herein include an apparatus comprising means to perform one or more elements of the method 900. This apparatus may be, for example, an apparatus of a UE (such as a wireless device 1202 that is a UE, as described herein).

[0164] Embodiments contemplated herein include one or more non -transitory computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of the method 900. This non-transitory computer-readable media may be. for example, a memory of a UE (such as a memory 1206 of a wireless device 1202 that is a UE. as described herein).

[0165] Embodiments contemplated herein include an apparatus comprising logic, modules, or circuitry to perform one or more elements of the method 900. This apparatus may be, for example, an apparatus of a UE (such as a wireless device 1202 that is a UE. as described herein).

[0166] Embodiments contemplated herein include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of the method 900. This apparatus may be, for example, an apparatus of a UE (such as a wireless device 1202 that is a UE, as described herein).

[0167] Embodiments contemplated herein include a signal as described in or related to one or more elements of the method 900.

[0168] Embodiments contemplated herein include a computer program or computer program product comprising instructions, wherein execution of the program by a processor is to cause the processor to carry out one or more elements of the method 900. The processor may be a processor of a UE (such as a processor(s) 1204 of a wireless device 1202 that is a UE, as described herein). These instructions may be, for example, located in the processor and / or on a memory of the UE (such as a memory 1206 of a wireless device 1202 that is a UE, as described herein).

[0169] Embodiments contemplated herein include an apparatus comprising means to perform one or more elements of the method 1000. This apparatus may be, for example,314907-1288-3843\1 P70336WO1an apparatus of a base station (such as a network device 1218 that is a base station, as described herein).

[0170] Embodiments contemplated herein include one or more non-transitory computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of the method 1000. This non-transitory computer-readable media may be, for example, a memory of a base station (such as a memory 1222 of a network device 1218 that is a base station, as described herein).

[0171] Embodiments contemplated herein include an apparatus comprising logic, modules, or circuitry to perform one or more elements of the method 1000. This apparatus may be, for example, an apparatus of a base station (such as a network device 1218 that is a base station, as described herein).

[0172] Embodiments contemplated herein include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of the method 1000. This apparatus may be, for example, an apparatus of a base station (such as a network device 1218 that is a base station, as described herein).

[0173] Embodiments contemplated herein include a signal as described in or related to one or more elements of the method 1000.

[0174] Embodiments contemplated herein include a computer program or computer program product comprising instructions, wherein execution of the program by a processing element is to cause the processing element to carry out one or more elements of the method 1000. The processor may be a processor of a base station (such as a processor(s) 1220 of a network device 1218 that is a base station, as described herein). These instructions may be, for example, located in the processor and / or on a memory of the base station (such as a memory 1222 of a network device 1218 that is a base station, as described herein).

[0175] For one or more embodiments, at least one of the components set forth in one or more of the preceding figures may be configured to perform one or more operations, techniques, processes, and / or methods as set forth herein. For example, a baseband processor as described herein in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth 324907-1288-3843\1 P70336WO1herein. For another example, circuitry associated with a UE, base station, network element, etc. as described above in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth herein.

[0176] Any of the above described embodiments may be combined with any other embodiment (or combination of embodiments), unless explicitly stated otherwise. The foregoing description of one or more implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of embodiments to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of various embodiments.

[0177] Embodiments and implementations of the systems and methods described herein may include various operations, which may be embodied in machine-executable instructions to be executed by a computer system. A computer system may include one or more general -purpose or special-purpose computers (or other electronic devices). The computer system may include hardware components that include specific logic for performing the operations or may include a combination of hardware, software, and / or firmware.

[0178] It should be recognized that the systems described herein include descriptions of specific embodiments. These embodiments can be combined into single systems, partially combined into other systems, split into multiple systems or divided or combined in other ways. In addition, it is contemplated that parameters, attributes, aspects, etc. of one embodiment can be used in another embodiment. The parameters, attributes, aspects, etc. are merely described in one or more embodiments for clarity, and it is recognized that the parameters, attributes, aspects, etc. can be combined with or substituted for parameters, attributes, aspects, etc. of another embodiment unless specifically disclaimed herein.

[0179] It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users.334907-1288-3843\1 P70336WO1

[0180] Although the foregoing has been described in some detail for purposes of clarity, it will be apparent that certain changes and modifications may be made without departing from the principles thereof. It should be noted that there are many alternative ways of implementing both the processes and apparatuses described herein. Accordingly, the present embodiments are to be considered illustrative and not restrictive, and the description is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.344907-1288-3843\1 P70336WO1

Claims

1. CLAIMS1. A method of a user equipment (UE), comprising:performing a measurement of a channel state information reference signal (CSI-RS) received from a base station;generating, based on the measurement, a precoder matrix indicator (PMI) that indicates a multiple-rank precoder W that is based on a W matrix that uses a first beam vector for each of a first polarization and a second polarization of an antenna array of a transmission reception point (TRP) of the base station, wherein the first beam vector is a result of a first uniform planar array (UPA) response calculation that uses a quantization mechanism over a first azimuth of the UE relative to a first antenna element of the antenna array, a first elevation of the UE relative to the first antenna element, and a first distance of the UE from the first antenna element; andsending, to the base station, channel state information (CSI) feedback comprising the PMI.

2. The method of claim 1, wherein the quantization mechanism over the first azimuth, the first elevation, and the first distance generates:a quantized azimuth of the UE relative to the first antenna element;a quantized elevation of the UE relative to the first antenna element; and a quantized distance of the UE from the first antenna element;wherein the quantized azimuth, the quantized elevation, and the quantized distance are used in the first UPA response calculation.

3. The method of claim 2, wherein the quantization mechanism generates information about the quantized azimuth, the quantized elevation, and the quantized distance jointly.

4. The method of claim 1, wherein the quantization mechanism over the first azimuth, the first elevation, and the first distance generates:a joint quantization of the first azimuth and the first elevation that maps to a first value of a set of defined values; anda quantized distance of the UE from the first antenna element;wherein the first value and the quantized distance are used in the first UPA response calculation.354907-1288-3843\1 P70336WO15. The method of claim 1, wherein the first beam vector comprises a discrete Fourier transform (DFT) beam vector.

6. The method of claim 1, wherein the Wi matrix uses the first beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array.

7. The method of claim 1, further comprising determining a modified first beam vector based on the first beam vector and a relative positioning of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array;wherein the Wi matrix uses the first beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and the modified first beam vector for each of the first polarization and the second polarization across the second virtual antenna panel.

8. The method of claim 1, wherein the W matrix further uses a second beam vector for each of the first polarization and the second polarization of the antenna array, wherein the second beam vector is a result of a second UPA response calculation that is different than the result of the first UPA response calculation.

9. The method of claim 8, wherein the Wi matrix uses the first beam vector and the second beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array.

10. The method of claim 8, further comprising:determining a modified first beam vector based on the first beam vector and a relative positioning of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array; anddetermining a modified second beam vector based on the second beam vector and the relative positioning of the first virtual antenna panel and the second virtual antenna panel;wherein:the Wi matrix uses the first beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and the modified first beam364907-1288-3843\1 P70336WO1vector for each of the first polarization and the second polarization across the second virtual antenna panel; andthe W matrix uses the second beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and the modified second beam vector for each of the first polarization and the second polarization across the second virtual antenna panel.

11. The method of claim 1, further comprising:performing a first interference measurement on a first interference measurement resource (IMR) and a second interference measurement on the second IMR; and determining, based on a comparison of the first interference measurement and the second interference measurement, that the first IMR corresponds to expected higher spectral efficiency at the UE than the second IMR;wherein the CSI feedback further comprises an indication of the first IMR.

12. The method of claim 1, wherein the multiple-rank precoder W is further based on a W2 matrix that makes a wideband indication corresponding to the W\ matrix.

13. The method of claim 1, wherein the multiple-rank precoder W is further based on a W2 matrix that makes a plurality of different sub-band indications corresponding to the Wi matrix.

14. A method of a base station, comprising:sending, to a UE, a channel state information reference signal (CSI-RS); receiving, from the UE, channel state information (CSI) feedback comprising a precoder matrix indicator (PMI) that indicates a multiple-rank precoder W that is based on a Wi matrix that uses a first beam vector for each of a first polarization and a second polarization of an antenna array of a transmission reception point (TRP) of the base station, wherein the first beam vector is a result of a first uniform planar array (UPA) response calculation that uses a quantization mechanism over a first azimuth of the UE relative to a first antenna element of the antenna array, a first elevation of the UE relative to the first antenna element, and a first distance of the UE from the first antenna element; and;precoding a downlink (DL) transmission to the UE using the multiple-rank precoder W.374907-1288-3843\1 P70336WO115. The method of claim 14, wherein the quantization mechanism over the first azimuth, the first elevation, and the first distance generates:a quantized azimuth of the UE relative to the first antenna element;a quantized elevation of the UE relative to the first antenna element; and a quantized distance of the UE from the first antenna element;wherein the quantized azimuth, the quantized elevation, and the quantized distance are used in the first UPA response calculation.

16. The method of claim 15, wherein the quantization mechanism generates information about the quantized azimuth, the quantized elevation, and the quantized distance jointly.

17. The method of claim 14, wherein the quantization mechanism over the first azimuth, the first elevation, and the first distance generates:a joint quantization of the first azimuth and the first elevation that maps to a first value of a set of defined values; anda quantized distance of the UE from the first antenna element;wherein the first value and the quantized distance are used in the first UPA response calculation.

18. The method of claim 14, wherein the first beam vector comprises a discrete Fourier transform (DFT) beam vector.

19. The method of claim 14, wherein the W matrix uses the first beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array.

20. The method of claim 14, wherein the W matrix uses the first beam vector for each of the first polarization and the second polarization across a first virtual antenna panel of the antenna array and a modified first beam vector for each of the first polarization and the second polarization across a second virtual antenna panel of the antenna array; wherein the modified first beam vector is based on the first beam vector and a relative positioning of the first virtual antenna panel the second virtual antenna panel.

21. The method of claim 14, wherein the W matrix further uses a second beam vector for each of the first polarization and the second polarization of the antenna array,384907-1288-3843\1 P70336WO1wherein the second beam vector is a result of a second UPA response calculation that is different than the first UPA response calculation.

22. The method of claim 21, wherein the W\ matrix uses the first beam vector and the second beam vector for each of the first polarization and the second polarization across each of a first virtual antenna panel of the antenna array and a second virtual antenna panel of the antenna array.

23. The method of claim 21, wherein:the Wi matrix uses the first beam vector for each of the first polarization and the second polarization across a first virtual antenna panel of the antenna array and a modified first beam vector for each of the first polarization and the second polarization across a second virtual antenna panel of the antenna array, wherein the modified first beam vector is based on the first beam vector and a relative positioning of the first virtual antenna panel the second virtual antenna panel; andthe Wi matrix uses the second beam vector for each of the first polarization and the second polarization across the first virtual antenna panel and a modified second beam vector for each of the first polarization and the second polarization across the second virtual antenna panel, wherein the modified second beam vector is based on the second beam vector and the relative positioning of the first virtual antenna panel and the second virtual antenna panel.

24. The method of claim 14, wherein the CSI feedback further comprises an indication of an interference measurement resource (IMR).

25. The method of claim 14, wherein the multiple-rank precoder W is further based on a Wi matrix that makes a wideband indication corresponding to the Wi matrix.

26. The method of claim 14, wherein the multiple-rank precoder W is further based on a W matrix that makes a plurality of different sub-band indications corresponding to the Wi matrix.

27. An apparatus comprising means to perform the method of any of claim 1 to claim 26.394907-1288-3843\1 P70336WO128. A computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform the method of any of claim 1 to claim 26.

29. An apparatus comprising logic, modules, or circuitry to perform the method of any of claim 1 to claim 26.

30. A baseband processor for a user equipment (UE) that is configured to cause the UE to perform one or more elements of any one of claim 1 to claim 13.

31. A baseband processor for a base station that is configured to cause the base station to perform one or more elements of any one of claim 14 to claim 26.404907-1288-3843\1 P70336WO1

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