Configurable precoder matrix indicator reporting

Abstract

Systems and methods of providing a configurable codebook based Precoder Matrix Indicator (PMI) report are provided. In some embodiments, a method performed by a user equipment (UE) includes: determining a first codebook based on signaling from a network node, determining a first index in a first index group based at least in part on the first codebook, determining a second index in a second index group based on a set of pre-defined codebooks and reporting to the network node a CSI report. Corresponding methods for a network node are also provided. In this way, a codebook-based PMI reporting that enables accurate CSI reporting for arbitrary type of antenna arrays at the network side including irregular subarrays is enabled.

Description

CONFIGURABLE PRECODER MATRIX INDICATOR REPORTING TECHNICAL FIELD

[0001] This disclosure relates generally to wireless communication and, more specifically, to a configurable precoder indicator reporting. BACKGROUND

[0002] Codebook-based precoding

[0003] Multi-antenna techniques can significantly increase the data rates and reliability of a wireless communication system. The performance is improved if both the transmitter and the receiver are equipped with multiple antennas, which results in a multiple-input multiple-output (MIMO) communication channel. Such systems and / or related techniques are commonly referred to as MIMO.

[0004] The NR standard is currently evolving with enhanced MIMO support. A core component in NR is the support of MIMO antenna deployments and MIMO related techniques like for instance spatial multiplexing. The spatial multiplexing mode is aimed for high data rates in favorable channel conditions. An illustration of the spatial multiplexing operation is provided in Figure 1.

[0005] As seen, the information carrying symbol vector s is multiplied by an NT x r precoder matrix ^^, which serves to distribute the transmit energy in a subspace of the NT(corresponding to NTantenna ports) dimensional vector space. The precoder matrix is typically selected from a codebook of possible precoder matrices, and typically indicated by means of a precoder matrix indicator (PMI), which specifies a unique precoder matrix in the codebook for a given number of symbol streams. The r symbols in s each correspond to a layer and r is referred to as the transmission rank. In this way, spatial multiplexing is achieved since multiple symbols can be transmitted simultaneously over the same time / frequency resource element (TFRE). The number of symbols r is typically adapted to suit the current channel properties.

[0006] NR uses OFDM in the downlink (and Discrete Fourier Transform (DFT) precoded OFDM in the uplink for rank- 1 transmission) and hence the received NR x 1 vector yn for a certain TFRE on subcarrier n (or alternatively data TFRE number n) is modeled by ^^^ ൌ ^^^^^^^^ ^ ^^^where en is a noise / interference vector obtained as realizations of a random process. The precoder ^^ can be a wideband precoder, which is constant over frequency, or frequency selective.

[0007] The precoder matrix ^^ is often chosen to match the characteristics of the NRxNTMIMO channel matrix ^^^, resulting in so-called channel dependent precoding. This is alsocommonly referred to as closed-loop precoding and essentially strives for focusing the transmit energy into a subspace which is strong in the sense of conveying much of the transmitted energy to the UE.

[0008] In closed-loop precoding for the NR downlink, the UE transmits, based on channel measurements in the downlink, recommendations to the gNB of a suitable precoder ^^ to use. This is the precoder matrix index reporting (PMI reporting), which is part of the CSI reporting.

[0009] The gNB configures the UE to provide feedback according to CSI-ReportConfig and may transmit CSI-RS and configure the UE to use measurements of CSI-RS to feed back recommended precoding matrices that the UE selects from a codebook. A single precoder that is supposed to cover a large bandwidth (wideband precoding) may be fed back. It may also be beneficial to match the frequency variations of the channel and instead feed back a frequency- selective precoding report, e.g. several precoders, one per subband. This is an example of the more general case of channel state information (CSI) feedback, which also encompasses feeding back other information than recommended precoders to assist the gNodeB in subsequent transmissions to the UE. Such other information may include channel quality indicators (CQIs) as well as transmission rank indicator (RI). In NR, CSI feedback can be either wideband, where one CSI is reported for the entire channel bandwidth, or frequency-selective, where one CSI is reported for each subband, which is defined as a number of contiguous resource blocks ranging between 4-32 PRBS depending on the band width part (BWP) size.

[0010] Given the CSI feedback from the UE, the gNB determines the transmission parameters it wishes to use to transmit to the UE, including the precoding matrix, transmission rank, and modulation and coding scheme (MCS). These transmission parameters may differ from the recommendations the UE makes. The transmission rank, and thus the number of spatiallymultiplexed layers, is reflected in the number of columns of the precoder ^^ . For efficientperformance, it is important that a transmission rank that matches the channel properties is selected.

[0011] 2D antenna arrays and subarrays

[0012] A two-dimensional antenna array may be (partly) described by the number of antenna columns corresponding to the horizontal dimension ^^^, the number of antenna rows corresponding to the vertical dimension ^^௩and the number of dimensions corresponding to differentpolarizations ^^^. The total number of antennas is thus ^^ ൌ ^^^^^௩^^^. The concept of an antennais non-limiting in the sense that it can refer to any virtualization (e.g., linear mapping) of the physical antenna elements. For example, pairs of physical sub-elements could be fed the same signal, and hence share the same virtualized antenna port.

[0013] An example of a 4x4 array with dual-polarized antenna elements is illustrated in Figure 2.

[0014] Precoding may be interpreted as multiplying the signal with different beamforming weights for each antenna prior to transmission. A typical approach is to tailor the precoder to theantenna form factor, i.e. taking into account ^^^ ,^^௩ and ^^^ when designing the precodercodebook.

[0015] In practical implementations, an “antenna element” is seldom a single radiation antenna element but instead a small array (a subarray) of vertical or horizontal antenna elements. Even a 2D array of antenna elements may constitute such a subarray.

[0016] The 2D antenna array thus typically consists of an array of identical subarrays. For the precoder codebook design perspective, the parameters ^^^,^^௩define the codebook for PMI reporting in NR and LTE and the design of the subarray is left to the implementation, assuming they are identical so that the array has the regular structure with equally spaced rows and columns of subarrays.

[0017] Channel State Information Reference Signals (CSI-RS)

[0018] For CSI measurement and feedback, CSI-RS are defined. A CSI-RS is transmitted on each antenna port and is used by a UE to measure downlink channel between each of the transmit antenna ports and each of its receive antenna ports. The transmit antenna ports are also referred to as CSI-RS ports. The supported number of antenna ports in NR are {1,2,4,8,12,16,24,32} which is extended in Release 19 to 128. By measuring the received CSI-RS, a UE can estimate the channel that the CSI-RS is traversing, including the radio propagation channel and antenna gains. The CSI-RS for the above purpose is also referred to as Non-Zero Power (NZP) CSI-RS.

[0019] CSI-RS can be configured to be transmitted in certain REs in a slot and certain slots. Figure 3 shows an example of CSI-RS REs for 12 antenna ports, where 1 RE per resource block (RB) per port is shown.

[0020] In addition, interference measurement resource (IMR) is also defined in NR for a UE to measure interference. An IMR resource contain 4 REs, either 4 adjacent RE in frequency in the same OFDM symbol or 2 by 2 adjacent REs in both time and frequency in a slot. By measuring both the channel based on NZP CSI-RS and the interference based on an IMR, a UE can estimate the effective channel and noise plus interference to determine the CSI, i.e. rank, precoding matrix, and the channel quality.

[0021] Furthermore, a UE in NR may be configured to measure interference based on one or multiple NZP CSI-RS resource.

[0022] CSI framework in NR

[0023] In NR, a UE can be configured with multiple CSI reporting settings and multiple CSI- RS resource settings. Each resource setting can contain multiple resource sets, and each resource set can contain up to 8 CSI-RS resources. For each CSI reporting setting, a UE may feed back a CSI report.

[0024] Each CSI reporting setting contains at least the following information: ^ A CSI-RS resource set for channel measurement ^ An IMR resource set for interference measurement ^ Optionally, a CSI-RS resource set for interference measurement ^ Time-domain behavior, i.e. periodic, semi-persistent, or aperiodic reporting ^ Frequency granularity, i.e. wideband or subband ^ CSI parameters to be reported such as RI, PMI, CQI, and CSI-RS resource indicator (CRI) in case of multiple CSI-RS resources in a resource set ^ Codebook types, i.e. type I or II, and codebook subset restriction ^ Measurement restriction ^ Subband size. One out of two possible subband sizes is indicated, the value range depends on the bandwidth of the BWP. One CQI / PMI (if configured for subband reporting) is fed back per subband).

[0025] When the CSI-RS resource set in a CSI reporting setting contains multiple CSI-RS resources, one of the CSI-RS resources is selected by a UE and a CSI-RS resource indicator (CRI) is also reported by the UE to indicate to the gNB about the selected CSI-RS resource in the resource set, together with RI, PMI and CQI associated with the selected CSI-RS resource.

[0026] For aperiodic CSI reporting in NR, more than one CSI reporting settings, each with a different CSI-RS resource set for channel measurement and / or resource set for interference measurement can be configured and triggered at the same time. In this case, multiple CSI reports are aggregated and sent from the UE to the gNB in a single PUSCH.

[0027] The Factorized Precoder Design in LTE and NR

[0028] Maintaining low signalling overhead is a critical design target in wireless systems. Signalling of precoders can easily consume a large portion of the resources unless carefully designed. The structure of possible precoders and the overall design of the precoder codebook plays an important role in keeping the signaling overhead low. A precoder structure used in both LTE and NR involves decomposing the precoder into two matrices, a so-called factorized precoder. The precoder can then be written as a product of two factors ^^ ൌ^^^ ^௧^= ^^^^^^^^where an ^^ ൈ ^^ conversion precoder ^^^^^்ே^ൈ^strives for capturing wideband / long-term propertiesof the channel such as correlation a ^^ ൈ ^^ tuning precoder ^^^௧^^ൈ^targets frequency- selective / short-term properties of Together they the overall precoder^^ which is induced by the signaled entities.ே ൈ^^^^^

[0029] The conversion precoder ^^ , sometimes also referred to as ^^ is typically, but not^^ே ൈ^^necessarily, reported with a coarser in time and / or frequency than the tuning precoderto save overhead and / or conversion precoder serves to exploit the correlation properties for focusing the tuning precoder in “directions” where the channel on average is “strong”. Typically, this is accomplished by reducing the number of dimensions k over which the tuning precoder should cover, i.e., the conversion precoder becomes a tall matrix with a reduced ^௧^number of columns and consequently the number of rows k of the tuning precoder ^^^ൈ^(sometimes referred to as ^^ ^ is reduced as well. With such a reduced number ofcodebook for the tuning precoder, which consumes most of the signaling resources to be updated with fine granularity, can be made smaller while still maintaining good performance.

[0030] The conversion ^^ and the tuning ^^ precoders each have a codebook of their own^^ ^^and an element in the codebook is indexed with by the family of ^^ parameters and by the family^of ^^ parameters, respectively. The conversion precoder targets having high spatial resolution andଶthus has a codebook with many elements while the codebook for the tuning precoder needs to be rather small in order to keep the signaling overhead at a reasonable level. The two codebooks can also be viewed as representing one larger codebook consisting of the set of precoders ^^^ ^௧^^^ obtained as all possible combinations of ^^ and ^^ . As already mentioned, forே ൈ^ ே ൈ^ ^ൈ^^ ^notational convenience, the conversion precoder to as ^^ and the tuning^^precoder ^^ leading to an effective precoder ^^ ൌ ^^ ^^ .^^ ^^ ^^

[0031] In LTE and NR, ^^ is the same for the entire system bandwidth, so-called wideband^^reporting, while ^^ can vary from one subband to another (a subband is a set of consecutive^^resource blocks over frequency) and thus supporting frequency-selective reporting. The second matrix ^^ could also be wideband but then reported more often in time than ^^ .^^ ^^

[0032] Theory on Grid of Beams

[0033] Some theory concerning grid of beams and DFT based precoding will be useful for later reference when describing the codebook. DFT based precoder vectors for N transmitTantennas can be written in the form^ே^,ொ^^ே^,ொ^^ே^,ொ^^ே^,ொ^் ^^^ ൌ ^^^^,^^^ଶ,^ ⋯ ^^ே^,^൧ 1 index (i.e., representingwhich beam out of the T beams) and Q is the oversampling factor. To get good performance itis important that the gain function of two consecutive beams overlap in the angular domainso that the gain does drop too much when going from one beam to another. Usually, this requires an oversampling factor of at least Q = 2. Thus for N antennas, at least 2N beams needed.T T

[0034] An alternative parameterization of the above DFT based precoder vectors is ் ^^^ே^,ொ^^ே^,ொ^^ே^,ொ^^ே^,ொ^^,^ ൌ ^^^^,ொ^ା^^^ଶ,ொ^ା ⋯ ^^^^ ே ,ொ^ା^^ ^^ ൌ 0,1,⋯ ,^^ െ 1where l and q together determine the precoder vector index via the relation n = Ql + q. This parameterization also highlights that there are Q groups of beams, where the beams within each group are orthogonal to each other. The q:th group can be represented by the generator matrix ^ே ^ ^ே ,ொ^^ே ,ொ^ ^ே ,ொ^^ ^^ ^^^ൌ(2)^^^^^⋯ ^^൧^ ^,^ ^,^ ே ି^,^^

[0035] the same generator matrix are beingused together as columns in the same precoder, it is easy to form sets of precoder vectors for use in so-called unitary precoding where the columns within a precoder matrix should form an orthonormal set.

[0036] To maximize the performance of DFT based precoding, it is useful to center the grid of beams symmetrically around the broad size of the array. Such rotation of the beams can be done ^ே ,ொ^^by multiplying from the left the above DFT vectors ^^ with a diagonal matrix ^^ havingrot^elementsగ^ ^^^ ൌ ^^^^^^ ^^^^^^rot ^^

[0037] included in the precoder codebook or alternatively be carriedout as a separate step where all signals are rotated in the same manner and the rotation can thus be absorbed into the channel from the perspective of the receiver (transparent to the receiver). Henceforth when we talk about DFT based precoding, it is tacitly assumed that rotation may ormay not have been carried out, i.e., both alternatives are possible without explicitly having to mention it.

[0038] A Factorized Precoder design based on Grid of Beams

[0039] As previously mentioned, the closely antenna subarray spaced dual polarized antenna is a common antenna array setup. As indicated in a previous section, the antennas can then be divided into two separate groups depending on the polarization direction of the antenna.

[0040] The correlation is high among the channels within an antenna group while channels from different antenna groups fade in an independent manner, and to some extent with reduced cross-talk due to the use of orthogonal polarizations. Such an antenna setup thus creates quite pronounced channel properties, which are well-matched to a block diagonal design along the lines of (4).

[0041] The precoder on the diagonal,^^^^^^, is targeting a co-polarized antenna group. Since the correlation is high within the antenna group, and since each subarray is assumed to be identical, it makes sense to use a grid of beam codebook implemented from DFT based precoder vectors. The outer precoder, ^^^௧^, adjusts the relative phase shift between polarizations. For rank 1, the precoder could for example be formed as ^^ ൌ ^^^^ ^^ 1^^ ^^^^ ^^^^ , ^^ ∈ ^1,െ1, ^^,െ^^^ (1)where the^^^^,ொ^ ൌ ⋃ொି^ ^^,ொ ^ୀ^ ^^^ ^ (2) with ^^^array is representing the set of all k-column columns subsets of the DFT based generator matrix ^^^ொ^^ having elements ଶగ ^^^^ொ^^ ^ൌ ^^^^^^ ^^^ ^^ ^^^ ^^ (3) where (forhere start from zero) ^^ ൌ 0,1,⋯ ,^^ െ 1, ^^ ൌ 0,1,⋯ ,^^் / 2 െ 1, ^^ ൌ 0,1,⋯ ,^^் / 2 െ 1 (4)

[0042] As seen, the tuning precoder ^^^௧^ ൌ ^ ^் adjusts the phase between a first and a1 ^^second group of antennas (in this case the first and second groups correspond to the upper and lower halves, respectively, of the rows of the precoder ^^). The rank 2 case would follow similarly as ^^ ^^^^ ^^ 1 1 ^^,ଶ^^^ ^^^^ ^^^ , ^^ ∈ ^1, ^^^, ^^^ ∈ ^^

[0043] In the case of 2D planar equally spaced antenna arrays with identical subarrays, then^^^^^^have the following structure^ ^^^^^ ൌ ^^^^^^ுwhere ^^^,^^ுrepresent the vertical and horizontal dimensions respectively and where the codebook for each of them have an 1D DFT structure. SUMMARY Systems and methods for a configurable PMI reporting are provided. In some embodiments, a method performed by a User Equipment (UE) includes determining a first codebook based on signaling from a network node, determining a first index in a first index group based at least in part on the first codebook, determining a second index in a second index group based on a set of pre-defined codebooks and reporting the first index and the second index to the network node (610) as part of a CSI report. The method may further include reporting subindices of the first index to the network node (610) as part of a CSI report. The first index may be an index i1for a conversion precoder W1and the second index may be an index i2 for a tuning precoder W2. The set of predefined codebooks may include codebooks from a standard specification. The method may further imclude receiving a first codebook configuration signaling from a network node and determining a first codebook based on the first codebook configuration signaling. The first codebook configuration signaling may indicate either that the user equipment is to be signaled the first codebook or that the user equipment is to use a standardized codebook as the first codebook. The first codebook configuration signaling may be a flag parameter, optionally configured either as part of CSI report configuration or a codebook configuration. The method may further include receiving the first codebook from the network node. The method may further include using the first codebook for CSI computation, if the user equipment receives the first codebook from the network node, or using a codebook specified by a standard if the user equipment does not receive a first codebook from the network node.A sub-structure of the first codebook may be selected from a set of predefined codebooks and a complementary structure is selected by the network node and signaled to the user equipment. The W1precoder may have a block diagonal structure: ^^ ൌ ^^^^0 ^0 ^^ଶ൨ integer, wherein, optionally, one or more^^^^^^ are constructed as normalized vectors; ^^^^^^ are constructed so that the first element ^^^^^^ (0) is always a constant; and / or vector elements ^^^^^^ ^^^^ , ^^ ൌ 0, .. ,^^ െ 1,0, .. , ^^ െ 1, ^^ ൌ 1,2 are quantized, optionally,as ^^^^^^ ^^^^ ∈and, optionally, a plurality of quantization points are given as, ^^^ ൌ1 and ^^ ∈ ^^^^^⁄ 4 , ^^ ൌ 0, .. ,7^.The first codebook may be a parameterized codebook, wherein, optionally, one or more of the following apply: the parametrized codebook is signaled to the user equipment from the network; one or more parameters associated for the parametrized codebook are signaled to the user equipment from the network; one or more parameters for a set of uncorrelated 1-D beams along a first dimension, such as an x-dimension, and / or one or more parameters for a set of uncorrelated 1-D beams along a first dimension, such as a y-dimension, are signaled to the user equipment from the network, wherein, optionally, whenever only one set of the one or more parameters from one of the first and second dimensions are signaled to the user equipment, the remaining set of one or more parameters for the other dimension is selected from a combination of one or more pre-defined vectors or matrices each one of one or more vectors in the first codebook or one or more vectors whose cross product is a vector in the first codebook, are a linear combination of one or morepredefined DFT matrices or vectors using a set of coefficients having amplitudes and phases. wherein, optionally, one or more of the following apply: the coefficients are signaled by the network node to the UE; the amplitudes of the coefficients in the linear combination are quantized using Mampbits and / or are predefined in standard specifications, wherein, optionally, Mamp is a per cell value and different cells may have different values; the phases of the coefficients in the linear combination are quantized using Mphasebits and / or are predefined in standard specifications, wherein, optionally, Mphase is a per cell value and different cells may have different values; and / or a selection of predefined DFT matrices out of the total number of predefined DFT matrices in the linear combinations are signaled to the user equipment by the network node, wherein, optionally, the selection can be indicated by either one of a bitmap or a combinatorial indicator; and / or the first codebook configuration is per cell, with different first codebook configurations allowable for different cells. The first index i1 may have two subindices i1,1 and i1,2 signalled, wherein subindex i1,1 points to a network node configured codebook, such as a fully parametrized codebook, and subindex i1,2 point to to a standardized codebook , such as a codebook of vectors, such as DFT vectors. According to some aspects, a method performed by a network node includes sending to a user equipment signaling that enables determination of a first codebook based on signaling from the network and receiving a CSI report comprising a first index and a second index, wherein the first index is in a first index group and is based at least in part on the first codebook and the second index is in a second index group and is based on a set of pre-defined codebooks. Similar features noted for the methods for the user equipment apply to methods for a networks node. According to some aspects, a user equipment including processing circuitry and memory is provided. The memory includes instructions to cause the user equipment to perform steps of the methods for the user equipment. According to some aspects, a network node including processing circuitry and memory is provided. The memory includes instructions to cause the user equipment to perform steps of the methods for the network node.According to some aspects, a computer-readable medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method for the user equipment or the method for the network node is provided. According to some aspects, a computer-readable medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out he method for the user equipment or the method for the network node is provided BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.

[0045] Figure 1 shows an example of a transmission structure of precoded spatial multiplexing mode in NR;

[0046] Figure 2 illustrates a two-dimensional antenna array of dual-polarized antenna elements (N_P=2), with N_h=4 horizontal antenna elements and N_v=4 vertical antenna elements anexample of a 4 ൈ 4 (i.e., ^^^ ൈ ^^ଶ,) array with dual-polarized antenna elements (i.e., ^^^ ൌ 2);

[0047] an example of Channel State Information Reference Signal (CSI-RS) Resource Elements (REs) for 12 antenna ports, where 1 RE per Resource Block (RB) per port is shown;

[0048] Figure 4A illustrates a flowchart of a method at a user equipment, according to some aspects of the present disclosure;

[0049] Figure 4B illustrates a flowchart of a method at a network node, according to some aspects of the present disclosure;

[0050] Figure 5 illustrates a example 2D antenna array for which value parameters ^^^^ ,^^^ , ^^ ൌ0,1 … ,^^^ െ 1; ^^ ൌ 0,1, … ,^^ଶ െ 1} associated with each dimension can be signaled / configured tothe UE in a parameterized codebook, according to some aspects of the present disclosure;

[0051] Figure 6 shows an example of a communication system in accordance with some aspects of the present disclosure;

[0052] Figure 7 shows a User Equipment device (UE) in accordance with ome aspects of the present disclosure;

[0053] Figure 8 shows a network node in accordance with ome aspects of the present disclosure;

[0054] Figure 9 is a block diagram of a host, which may be an embodiment of the host of Figure 6, in accordance with various aspects of the present disclosure described herein;

[0055] Figure 10 is a block diagram illustrating a virtualization environment in which functions implemented by some embodiments of the present disclosure may be virtualized; and

[0056] Figure 11 shows a communication diagram of a host communicating via a network node with a UE over a partially wireless connection in accordance with s ome aspects of the present disclosure. DETAILED DESCRIPTION

[0057] The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure.

[0058] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0059] There currently exist certain challenge(s). Existing codebook-based PMI reporting in NR and LTE are designed based on an underlying model of the antenna array structure at the network side, namely a linearly spaced planar array of planar (and equally designed) subarrays.

[0060] It is a problem that this assumption by design prohibits accurate PMI reporting for other types of antenna arrays. It is of interest to design other types of antenna arrays that for example have lower sidelobes so that co-existence with satellite or terrestrial radar systems is minimized. Such co-existence is an increasing problem for NR and 6G frequency bands.

[0061] Hence, it is a problem how to modify the existing codebook-based PMI reporting (and design a more versatile PMI reporting scheme in 6G) to enable accurate CSI reporting for these new type of antenna arrays at the network side.

[0062] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. According to these aspect, part of the PMI codebook is configurable to the UE. In certain aspects, a first codebook, such as the matrix ^^^^(which can be as reported by thefamily of ^^^parameters in the CSI report) is configurable while a second codebook, such as the remaining matrices, e.g. ^^^^, are given by the standard specifications.

[0063] to certain aspects, the elements of the matrices ^^^^in the codebook are based on a partial or fully flexible approach (arbitrary, quantized vectors subject to some defined normalization) and / or a parametrized approach.

[0064] The configuration of parts of the PMI codebook from NW to UE could be performed using higher layer signaling, e.g. Radio Resource Control (RRC) or Medium Access Control (MAC) Control Element (CE).

[0065] Certain embodiments may provide one or more of the following technical advantage(s). The proposed methods provide a codebook-based PMI reporting that enables accurate CSI reporting for arbitrary type of antenna arrays at the network side, including irregular subarrays.

[0066] In some embodiments disclosed herein, a first codebook, e.g. W1, can be configured from the NW to the UE. In particular, the first codebook, e.g. W1, may still have some standardized structure such as a DFT structure in one dimension (such as a dimension considered vertical, which can use linearly spaced antenna subarrays) but the NW can choose and configure to the UE for the other dimension(s) (such as a dimension considered ‘horizontal’, using non-linear spaced antenna subarrays). An important application is the case when the subarrays that constitute the 2D antenna array are irregular, i.e. they are not equal, e.g. are using tiled subarray blocks.

[0067] Some aspects disclosed herein are depicted in the flowchart of Figure 4A. According to some aspects, a method for a user equipment (UE) includes determining (100) a first codebook based on signaling from the network, determining (102) a first index in a first index group based at least in part on the first codebook, determining (104) a second index in a second index group based on a set of pre-defined codebooks and reporting (106) a CSI report. Optionally, the first index is an index i1 for a conversion precoder W1and the second index is index i2 for a tuning precoder W2. Figure 4B illustrates a flowchart for a method at a network node, according to other aspects of the disclosure. The method includes sending (200) to a user equipment (700) signaling that enables determination of a first codebook based on signaling from the network and receiving (202) a CSI report comprising a first index and a second index, wherein the first index is in a first index group and is based at least in part on the first codebook and the second index is in a second index group and is based on a set of pre-defined codebooks.

[0068] According to some additional aspects, a method for PMI reporting from a user equipment (UE) to the network (NW) where a preferred MIMO precoder (W) from a codebook is defined by a plurality of indices (i1, i2,..) representing a first, second, …sets of index groups, respectively. According to some embodiments, the method comprises:^ determining a first index (i1) in a first index group (e.g for W1) based on an at least partly configured codebook by the network to the UE ^ determining a second index (i2) in a second index group (e.g for W2,Wf,..) at least in part based on a set of pre-defined codebooks, e.g. in a standard specification and where, optionally, the NW has configured the UE which of the pre-defined codebooks to use; optionally, the determination of the second index (i2) in a second index group is entirely based on a set of pre-defined codebooks, ^ reporting the first index (i1), optionally along with subindices indices of the first index, e.g. ^^^,^and ^^^,ଶand the second index i2to the network as part of a CSI report

[0069] Fully flexible antenna array structure, including irregular subarrays: Additionally or alternatively, , the first index group (for W1) is further described by the sub-indices ^^^,^and ^^^,ଶwhere ^^^,^selects a vector or matrix ^^^in a first dimension which has been configured by the NW to the UE [and is thus not given by the standard specifications] and ^^^,ଶselects a vector or matrix ^^ுof a second dimension which has been configured by the NW to the UE [and is thusnot given by the standard specifications] where ^^^ ൌ ^^^^^^ு.

[0070] Fully flexible antenna array structure in one dimension, standardized in the other dimension: Additionally or alternatively, [], the first index group (for W1) is further described by sub-indices ^^^,^and ^^^,ଶwhere ^^^,^selects a DFT vector or matrix ^^^in the first dimension and ^^^,ଶselects a vector or matrix ^^ுof a second dimensions which has been configured by the NWto the UE [and is thus not given by the standard specifications] where ^^^ ൌ ^^^^^^ு.

[0071] The NR codebook can be written using the factorized precoderabove although not obvious to the reader on the specifications as the factorized precoder design is not directly visible.

[0072] In NR specifications, the factorized design is however implicitly reflected by the indices ^^^,^and ^^^,ଶ(as specified in 3GPP TS 38.214 V18.2.0) which selects the DFT vectors inthe first (e.g. ‘vertical’) and second (e.g. horizontal) dimensions in ^^^ ൌ ^^^^^^ு and the index^^ଶ(as specified in 3GPP TS 38.214 V18.2.0) which selects ^^ଶ.These indices jointly determine the final MIMO precoder ^^= ^^^^^^^^.

[0073] Note that in NR Rel.16, for eType-II codebooks, another matrix was introduced to capture the frequency domain characteristics and it requires more sub-indices in both the ^^^and ^^ଶset of indices: ^^ ൌ ^^^^^^ …^^^ேయି^^൧ ൌ ^^^^^^ଶ^^^ு

[0074] Since ^^^represents the spatial dimensions of the antenna array, and since the assumption was that arrays are uniform linear arrays with identical subarrays, it was decided to have a ^^^with certain (DFT-based) structure in NR.

[0075] In some aspects of the present disclosure, the codebook for ^^^may be signaled (e.g., via higher layers such as an RRC configuration or MAC CE) from the network to the UE to reflect the actually used antenna array in order to maximize the accuracy of the PMI report. If the network doesn’t perform this signalling of the ^^^codebook (i.e., a set of candidate PMI vectors or matrices for ^^^codebook, or indicators for such candidate PMI vectors or matrices ^^^codebook), or ifthe UE is otherwise indicated not a network signaled ^^^codebook, then a standardized codebook (i.e., a set of candidate PMI vectors or matrices predefined in e.g., 3GPP standard specifications) for ^^^can be used instead. For instance, as part of the signaling, the UE may receives one or more indications from the network (e.g., via a RRC parameter) which may determine whether the ^^^codebook is signaled to the UE, whether to use a ^^^codebook signaled to the UE or whether the UE shall use a standardized codebook for ^^^.

[0076] In some aspects of the disclosure, a flag parameter, e.g. configured as part of CSI reporting configuration or codebook configuration, is indicated by the network to the UE such that ^ if the flag parameter is present or if the flag parameter is set to a first value, then the UE shall receive, or expect to receive or to have received, signaling of the ^^^codebook from the network; ^ if the flag parameter is absent or if the flag parameter is set to a second value, then the UE shall use a standardized codebook for ^^^.

[0077] Alternatively, if the ^^^codebook is signaled from the network to the UE, then the UE shall use the signaled ^^^codebook for CSI computation. Otherwise, the UE shall use a standardized codebook for ^^^.

[0078] Additionally or alternatively, a UE may receive an indication, e.g. via higher layer signaling such as RRC or MAC CE, indicating that even if the ^^^codebook is signaled from the network to the UE, the UE shall ignore the signaled ^^^codebook for CSI computation and use a standardized codebook for ^^^. Such an approach, with a fallback to a known, standardized codebook for W1, could, for example, be useful if some problems are observed with the signaled codebook for W1. It may also be so that, the standardized codebook for W1 is tested by various tests, e.g. RAN4 / RAN5 tests, so a guaranteed performance is provided while the signaled codebook is not tested.

[0079] The index / indices that select a matrix ^^^in the PMI report (e.g. indices ^^^,^and ^^^,ଶ) can be termed the first group of indices and the remaining index / indices (e.g index ^^ଶ) can betermed the second group of indices. What differentiates these groups is that the first group requires a configuration of the associated codebook (for example the matrix elements in the codebook for ^^^) and the second group is given by the standard specifications.

[0080] Note however that for the second group, there may be a need for some network signaling to UE a configuration to select one out of multiple standardized codebooks (e.g., for ^^ଶ). However, in the first group, the elements of the actual codebook for ^^^are not fully given by the standard specifications, it requires said additional configuration by the network.

[0081] Some further aspects on how the configuration signalling of the codebook for ^^^can be designed are described next.

[0082] Fully flexible codebook for ^^^

[0083] According to certain aspect, a codebook suitable to support arbitrary antenna arrays, including spherical or cylindrical antenna arrays, irregularly shaped subarrays and non-equal subarray antenna spacing is provided. It can also be used to define a codebook that is adjusted to perform well in the electro magnetic nearfield of the antenna array.

[0084] According to these aspects, the ^^^matrix has the following structure that allows the re-use of the legacy codebook principles for dual polarized antenna arrays (the block diagonal structure of ^^^) and PMI reporting components for ^^ଶ^^^ ൌ ^^^^0 0^^ଶ൨ where ^^^ ൌ ^^^ ^^^^ … ^^^^^^ ൧ is a matrix associated to antenna ports at the ithpolarization and ^^^^^^beam associated to the ithpolarization, ^^^^^^ may be constructed as normalized vector. ^^^^^may also be constructed so that the first element ^^^^^(0) is always a constant, e.g. ^^^^^^^ ^(0) =1. Since the elements of the matrix B1 can be set arbitrarily (there is no structure among the elements, e.g. DFT structure as in NR). This means W1can be tailored to fit any antenna array geometry shape. For example, Bessel functions can be used as vectors in B1 (without the need to standardize Bessel function codebook),

[0085] The vector elements ^^^^^^ ^^^^ , ^^ ൌ 0, .. ,^^ െ 1, ^^ ൌ 0, .. , ^^ െ 1, ^^ ൌ 1,2 are quantized,where K is the number of antenna ports per polarization, L is the number of beams. for example as: ^^^^^^ ^^^^ ∈ ^^^^^^ఝ^

[0086] For example, theare given as, ^^^ ൌ 1 and ^^^ ∈^^^^^⁄ 4 , ^^ ൌ 0, .. ,7^, then 3 bits are needed for ^^^^^^ ^^^^. Assuming a CSI-RS resource with 32 ports, i.e., K=16, and up to rank 4 reporting with ^^ ൌ 4 beams, for layer common ^^^, signalling of^^^from network to the UE requires 3bits (for phase)*4 (L)*16(K)*2(polarizations) = 384 bits.

[0087] In general, amplitude ^^^may be quantized using a number ^^^^^of bits, where the amplitudes corresponding to the 2ெೌ^^codepoints for signaling each ^^^are predefined in 3GPP specifications.

[0088] A parametrized codebook for ^^^^

[0089] Additionally or alternatively, a parameterized codebook can be signalled to the UE from the network, e.g. using RRC configuration of the codebook.

[0090] An example is shown in relation with Figure 5. A 2D beam ^^^.^can be expressed as^^^.^ ൌ ^^^ ⊗ ^^^^n is the angle quantization index, e.g. quantize sin(θ) in azimuth uniformly into N1associated angles.

[0091] The parameters ^^^^^ ,^^^^ , ^^௫ ൌ 0,1 … ,^^^ െ 1; ^^௬ ൌ 0,1, … ,^^ଶ െ 1 } are in unit ofwavelength and can be signaled / configured toUE. ^^^^,^^ ൌ 0, 1, … ,^^^^^^ െ 1^ are a set ofoversampled 1-D beams along a first dimension,^^^^,^^ ൌ0,1, … ,^^ଶ^^ଶ െ 1^ are a set of oversampled 1-D beams along a second dimension, also referred toas y dimension. ^^^^^^ ∈ ^^^^.^,^^ ൌ 0, 1, … ,^^^^^^ െ 1;^^ ൌ 0,1, … ,^^ଶ^^ଶ െ 1^. N1, N2, are thenumber ofthe x and y dimension, respectively and O1 (^^^ ^ 1^ and O2 (^^ଶ ^1^ are oversampling factors along these respective dimensions. ^^ and ^^ can be expressed as ^^ ൌ^^௫^^^ ^ ^^^ and ^^ ൌ ^^௬^^ଶ ^ ^^ଶ , where ^^^ ൌ 0,1, … ,^^^ െ 1;^^ଶ ൌ 0,1, … ,^^ଶ െ 1; ^^௫ ൌ0,1 … ,^^^ െ 1;^^௬ ൌ 0,1, … ,^^ଶ െ 1.of the 2D beams, ^^^^^^^ … ^^^^^^ ൧, selected by a UE, a beam index ^^^,^^^ can be reported. The selectedsame beam grid, i.e., with a same ^^^^,^^ଶ^, which may also be reported. With the reported beam indices by the UE, the network can determineeach of the 2D beams ^^^ ^^^ … ^^ ^^^^ ^ ൧ according to ^^^.^ ൌ ^^^ ⊗ ^^^.

[0093] Additionally or alternatively, a set of predefined vectors / matrices (e.g., DFT vectors / matrices) may be predefined in 3GPP specifications as follows:^ଶగ^^ଶగ^^ேభି^^ ^^^ ൌ ^1 ^^ ேభ , … , ^^ேభ^Then, the PMI vectors in the signaled codebookofof the predefined DFT matrices / vectors (that may be described inspecifications) such that ^ୀேమି^, ^ୀேభି^ ^^^^where ^^ r௧^ ^^^^^epresents the ^^ PMI ^^^^. For each PMI vector ^^ in the^codebook for ^^^^, the network signals / configures a set of coefficients ^^^^,^to the can bedone by L2 signalling such as MAC CE or by L3 signaling such as RRC When the UE has received such configuration, the UE may be configured to use this codebook for all cells it is connected to.

[0094] Additionally or alternatively, the amplitudes of the different coefficients ^^^^,^are quantized using a number ^^^^^of bits, where the amplitudes corresponding 2ெೌ^^codepoints are predefined in 3GPP specifications. In another embodiment, the phases of the different coefficients ^^^^,^are quantized using a number ^^^^^^^of bits, where the phase values corresponding to thecodepoints are predefined in 3GPP specifications.

[0095] Additionally or alternatively, the PMI vectors in the signaled codebook of ^^^^arerepresented as a linear combination of a subset of the predefined DFT matrices. Let ^^^^,^^ , ^^ ൌ1, 2, … ,^^ represent the subset of the predefined DFT matrices to be used in thecombiningwhere ^^^ ∈ 0,1, … ,^^ଶ െ 1 and ^^^ ∈ 0,1, … ,^^^ െ 1. Then, the PMI vectors in the signaledcodebook of ^^^^are represented as a linearof the finite number of predefined DFT matrices such that ொ ^

[0096] Additionally orthe subset of predefined DFT matrices^^^^,^^ , ^^ ൌ 1, 2, … ,^^ are signaled to the UE from the network. In one embodiment, a bitmap with^^ gh o^^^ len t ^lଶ^^ ^^ can indicate the selection of ^^ predefined DFT matrices out of the totalDFT matrices. In another embodiment, a combinatorial indicator can beused to indicate the selection of ^^ predefined DFT matrices out of the total number of predefined DFT matrices.

[0097] Additionally or alternatively, the codebook of ^^^^is configured separately for each cell, so that the UE can use a high-resolution reporting on one cell and a lower on another cell where the configuration of ^^^^^and ^^^^^^^may be different for the different cell configurations.

[0098] Although in the above ^^^^is shown as being represented as a linear combination of predefined 2D DFT beams, the described embodiments are non-limiting and the linearcombination can be done in 1D. For instance, let ^^^^ ൌ ^^^^,^^ ⊗ ^^^^,^^ . Then, additionally oralternatively, the 1D vector ^^^^,^^can be represented as a linear combination of predefined 1D DFT vectors. Similarly, the 1D vector ^^^^,^^can, additionally or alternatively, be represented as a linear combination of predefined 1D DFT vectors. Additionally or alternatively, only ^^^^,^^can be represented as a linear combination of predefined 1D DFT vectors, while ^^^^,^^are drawn from predefined 1D DFT vectors.

[0099] Partial flexible codebook for ^^^where 1D out of the 2D codebook is configurable by the NW to the UE

[0100] Additionally or alternatively, the antenna array is a 2D array but it is not assumed to be a uniform spaced antenna array (or subarrays) in both dimensions. Hence, a first dimension can use a 1D codebook of DFT vectors as array response vectors (as in legacy codebooks used in NR), while the second dimension has irregular antenna spacing or subarray spacing and cannot efficiently use the DFT based array response vectors. Some aspects of the present disclosure attempt to address this problem by enabling a combination of a pre-defined DFT vector in one dimension (that is suitable for uniformly spaced antennas) and configurable by the NW in the other dimension.

[0101] An example is where antenna elements are equally spaced (uniform) in the vertical direction, while non-uniform in the horizontal direction,

[0102] In this case, a 2D beam ^^^.^ can be expressed as ^^^.^ ൌ ^^^ ⊗ ^^^where ^ ଶగ^ ^ଶగ^ேభைభି^^^ ^^^ ^1 ^^ … ^^ ^^

[0103] The parameters ^^^^ , ^^ ൌ 0,1, … ,^^ଶ െ 1} can be signaled / configured to the UE.^^^^,^^ ൌ 0,1, … , N^^^^ െ 1^ are a set of uncorrelated 1-D beams along x dimension .

[0104] Here, ^^^^,^^ ൌ 0,1, … ,^^ଶ^^ଶ െ 1^ are a set of 1-D beams along y dimension that areparametrized by the element positions {^^^ , ^^ ൌ 0,1, … ,^^ଶ െ 1 ^ .

[0105] The 2D beam vector is then ^^^^^^ ∈ ^^^^.^,^^ ൌ 0,1, … , N^^^^ െ 1;^^ ൌ 0,1, … ,^^ଶ^^ଶ െ1^.

[0106] Or described more generally, a 2D beam ^^^.^ can as ^^^.^ ൌ ^^^ ⊗ ^^^where ^ଶగ^^ଶగ^^ேభைభି^^ ^^^ ൌ ^1 ^^ ேభைభ , … , ^^ேభைభ^ 0,1, … ,^^ଶ െ 1 } have unit norm and can besome standardized quantization of phase or phase+amplitude. ^^^^,^^ ൌ 0,1, … , N^^^^ െ 1^ are a set of uncorrelated 1-D beams along x dimension.

[0108] The 2D beam vector is then ^^^^^^ ∈ ^^^^.^,^^ ൌ 0,1, … , N^^^^ െ 1;^^ ൌ 0,1, … ,^^ଶ^^ଶ െ1^.

[0109] For each of the 2D beams, ^^^ ^^^^ … ^^^^^^ ൧, selected by a UE, a beam index ^^^,^^^ can be reported. The selected same beam grid, i.e., with a same ^^^ ,^^ ^,^ ଶwhich may also be reported.

[0110] Figure 6 shows an example of a communication system 600 in accordance with some embodiments.

[0111] In the example, the communication system 600 includes a telecommunication network 602 that includes an access network 604, such as a Radio Access Network (RAN), and a core network 606, which includes one or more core network nodes 608. The access network 604 includes one or more access network nodes, such as network nodes 610A and 610B (one or more of which may be generally referred to as network nodes 610), or any other similar Third Generation Partnership Project (3GPP) access nodes or non-3GPP Access Points (APs). Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network 602 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 602 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operatealone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 602, including one or more network nodes 610 and / or core network nodes 608.

[0112] Examples of an ORAN network node include an Open Radio Unit (O-RU), an Open Distributed Unit (O-DU), an Open Central Unit (O-CU), including an O-CU Control Plane (O- CU-CP) or an O-CU User Plane (O-CU-UP), a RAN intelligent controller (near-real time or non- real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). The network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an A1, F1, W1, E1, E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Moreover, an ORAN access node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an O-2 interface defined by the O-RAN Alliance or comparable technologies. The network nodes 610 facilitate direct or indirect connection of User Equipment (UE), such as by connecting UEs 612A, 612B, 612C, and 612D (one or more of which may be generally referred to as UEs 612) to the core network 606 over one or more wireless connections.

[0113] Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 600 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 600 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0114] The UEs 612 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 610 and other communication devices. Similarly, the network nodes 610 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 612 and / or with other network nodes or equipment in the telecommunication network 602 toenable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 602.

[0115] In the depicted example, the core network 606 connects the network nodes 610 to one or more hosts, such as host 616. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 606 includes one more core network nodes (e.g., core network node 608) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 608. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-Concealing Function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF).

[0116] The host 616 may be under the ownership or control of a service provider other than an operator or provider of the access network 604 and / or the telecommunication network 602 and may be operated by the service provider or on behalf of the service provider. The host 616 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

[0117] As a whole, the communication system 600 of Figure 6 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system 600 may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable Second, Third, Fourth, or Fifth Generation (2G, 3G, 4G, or 5G) standards, or any applicable future generation standard (e.g., Sixth Generation (6G)); Wireless Local Area Network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.6 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication(NFC) ZigBee, LiFi, and / or any Low Power Wide Area Network (LPWAN) standards such as LoRa and Sigfox.

[0118] In some examples, the telecommunication network 602 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunication network 602 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 602. For example, the telecommunication network 602 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing enhanced Mobile Broadband (eMBB) services to other UEs, and / or massive Machine Type Communication (mMTC) / massive Internet of Things (IoT) services to yet further UEs.

[0119] In some examples, the UEs 612 are configured to transmit and / or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 604 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 604. Additionally, a UE may be configured for operating in single- or multi-Radio Access Technology (RAT) or multi-standard mode. For example, a UE may operate with any one or combination of WiFi, New Radio (NR), and LTE, i.e., being configured for Multi-Radio Dual Connectivity (MR-DC), such as Evolved UMTS Terrestrial RAN (E-UTRAN) NR - Dual Connectivity (EN-DC).

[0120] In the example, a hub 614 communicates with the access network 604 to facilitate indirect communication between one or more UEs (e.g., UE 612C and / or 612D) and network nodes (e.g., network node 610B). In some examples, the hub 614 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 614 may be a broadband router enabling access to the core network 606 for the UEs. As another example, the hub 614 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 610, or by executable code, script, process, or other instructions in the hub 614. As another example, the hub 614 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 614 may be a content source. For example, for a UE that is a Virtual Reality (VR) headset, display, loudspeaker or other media delivery device, the hub 614 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 614 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example,the hub 614 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy IoT devices.

[0121] The hub 614 may have a constant / persistent or intermittent connection to the network node 610B. The hub 614 may also allow for a different communication scheme and / or schedule between the hub 614 and UEs (e.g., UE 612C and / or 612D), and between the hub 614 and the core network 606. In other examples, the hub 614 is connected to the core network 606 and / or one or more UEs via a wired connection. Moreover, the hub 614 may be configured to connect to a Machine-to-Machine (M2M) service provider over the access network 604 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 610 while still connected via the hub 614 via a wired or wireless connection. In some embodiments, the hub 614 may be a dedicated hub – that is, a hub whose primary function is to route communications to / from the UEs from / to the network node 610B. In other embodiments, the hub 614 may be a non-dedicated hub – that is, a device which is capable of operating to route communications between the UEs and the network node 610B, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0122] Figure 7 shows a UE 700 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged, and / or operable to communicate wirelessly with network nodes and / or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, Voice over Internet Protocol (VoIP) phone, wireless local loop phone, desktop computer, Personal Digital Assistant (PDA), wireless camera, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, Laptop Embedded Equipment (LEE), Laptop Mounted Equipment (LME), smart device, wireless Customer Premise Equipment (CPE), vehicle, vehicle-mounted or vehicle embedded / integrated wireless device, etc. Other examples include any UE identified by the 3GPP, including a Narrowband Internet of Things (NB-IoT) UE, a Machine Type Communication (MTC) UE, and / or an enhanced MTC (eMTC) UE.

[0123] A UE may support Device-to-Device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I), or Vehicle- to-Everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and / or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller).Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0124] The UE 700 includes processing circuitry 702 that is operatively coupled via a bus 704 to an input / output interface 706, a power source 708, memory 710, a communication interface 712, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 7. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0125] The processing circuitry 702 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 710. The processing circuitry 702 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general purpose processors, such as a microprocessor or Digital Signal Processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 702 may include multiple Central Processing Units (CPUs).

[0126] In the example, the input / output interface 706 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 700. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

[0127] In some embodiments, the power source 708 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 708 may further include powercircuitry for delivering power from the power source 708 itself, and / or an external power source, to the various parts of the UE 700 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 708. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 708 to make the power suitable for the respective components of the UE 700 to which power is supplied.

[0128] The memory 710 may be or be configured to include memory such as Random Access Memory (RAM), Read Only Memory (ROM), Programmable ROM (PROM), Erasable PROM (EPROM), Electrically EPROM (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 710 includes one or more application programs 714, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 716. The memory 710 may store, for use by the UE 700, any of a variety of various operating systems or combinations of operating systems.

[0129] The memory 710 may be configured to include a number of physical drive units, such as Redundant Array of Independent Disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, High Density Digital Versatile Disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, Holographic Digital Data Storage (HDDS) optical disc drive, external mini Dual In-line Memory Module (DIMM), Synchronous Dynamic RAM (SDRAM), external micro-DIMM SDRAM, smartcard memory such as a tamper resistant module in the form of a Universal Integrated Circuit Card (UICC) including one or more Subscriber Identity Modules (SIMs), such as a Universal SIM (USIM) and / or Internet Protocol Multimedia Services Identity Module (ISIM), other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as a ‘SIM card.’ The memory 710 may allow the UE 700 to access instructions, application programs, and the like stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system, may be tangibly embodied as or in the memory 710, which may be or comprise a device-readable storage medium.

[0130] The processing circuitry 702 may be configured to communicate with an access network or other network using the communication interface 712. The communication interface 712 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 722. The communication interface 712 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a networknode in an access network). Each transceiver may include a transmitter 718 and / or a receiver 720 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 718 and receiver 720 may be coupled to one or more antennas (e.g., the antenna 722) and may share circuit components, software, or firmware, or alternatively be implemented separately.

[0131] In the illustrated embodiment, communication functions of the communication interface 712 may include cellular communication, WiFi communication, LPWAN communication, data communication, voice communication, multimedia communication, short- range communications such as Bluetooth, NFC, location-based communication such as the use of the Global Positioning System (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented according to one or more communication protocols and / or standards, such as IEEE 802.6, Code Division Multiplexing Access (CDMA), Wideband CDMA (WCDMA), GSM, LTE, NR, UMTS, WiMax, Ethernet, Transmission Control Protocol / Internet Protocol (TCP / IP), Synchronous Optical Networking (SONET), Asynchronous Transfer Mode (ATM), Quick User Datagram Protocol Internet Connection (QUIC), Hypertext Transfer Protocol (HTTP), and so forth.

[0132] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 712, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 10 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).

[0133] As another example, a UE comprises an actuator, a motor, or a switch related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

[0134] A UE, when in the form of an IoT device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application, and healthcare. Non-limiting examples of such an IoT device are a device which is or which is embedded in: a connected refrigerator or freezer, a television, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smartspeaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door / window sensor, a flood / moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or VR, a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an IoT device comprises circuitry and / or software in dependence of the intended application of the IoT device in addition to other components as described in relation to the UE 700 shown in Figure 7.

[0135] As yet another specific example, in an IoT scenario, a UE may represent a machine or other device that performs monitoring and / or measurements and transmits the results of such monitoring and / or measurements to another UE and / or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship, an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0136] In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g., by controlling an actuator) to increase or decrease the drone’s speed. The first and / or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator and handle communication of data for both the speed sensor and the actuators.

[0137] Figure 8 shows a network node 800 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged, and / or operable to communicate directly or indirectly with a UE and / or with other network nodes or equipment in a telecommunication network. Examples of network nodes include, but are not limited to, APs (e.g., radio APs), Base Stations (BSs) (e.g., radio BSs, Node Bs, evolved Node Bs (eNBs), NR Node Bs (gNBs)), and O-RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O-CU).

[0138] Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units, distributed units (e.g., in an O-RAN access node), and / or Remote Radio Units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such RRUs may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a Distributed Antenna System (DAS).

[0139] Other examples of network nodes include multiple Transmission Point (multi-TRP) 5G access nodes, Multi-Standard Radio (MSR) equipment such as MSR BSs, network controllers such as Radio Network Controllers (RNCs) or BS Controllers (BSCs), Base Transceiver Stations (BTSs), transmission points, transmission nodes, Multi-Cell / Multicast Coordination Entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and / or Minimization of Drive Tests (MDTs).

[0140] The network node 800 includes processing circuitry 802, memory 804, a communication interface 806, and a power source 808. The network node 800 may be composed of multiple physically separate components (e.g., a NodeB component and an RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 800 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair may in some instances be considered a single separate network node. In some embodiments, the network node 800 may be configured to support multiple RATs. In such embodiments, some components may be duplicated (e.g., separate memory 804 for different RATs) and some components may be reused (e.g., a same antenna 810 may be shared by different RATs). The network node 800 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 800, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, Long Range Wide Area Network (LoRaWAN), Radio Frequency Identification (RFID), or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within the network node 800.

[0141] The processing circuitry 802 may comprise a combination of one or more of a microprocessor, controller, microcontroller, CPU, DSP, ASIC, FPGA, or any other suitable computing device, resource, or combination of hardware, software, and / or encoded logic operable to provide, either alone or in conjunction with other network node 800 components, such as the memory 804, to provide network node 800 functionality.

[0142] In some embodiments, the processing circuitry 802 includes a System on a Chip (SOC). In some embodiments, the processing circuitry 802 includes one or more of Radio Frequency (RF) transceiver circuitry 812 and baseband processing circuitry 814. In some embodiments, the RF transceiver circuitry 812 and the baseband processing circuitry 814 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of the RF transceiver circuitry 812 and the baseband processing circuitry 814 may be on the same chip or set of chips, boards, or units.

[0143] The memory 804 may comprise any form of volatile or non-volatile computer-readable memory including, without limitation, persistent storage, solid state memory, remotely mounted memory, magnetic media, optical media, RAM, ROM, mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD), or a Digital Video Disk (DVD)), and / or any other volatile or non-volatile, non-transitory device-readable, and / or computer-executable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 802. The memory 804 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and / or other instructions capable of being executed by the processing circuitry 802 and utilized by the network node 800. The memory 804 may be used to store any calculations made by the processing circuitry 802 and / or any data received via the communication interface 806. In some embodiments, the processing circuitry 802 and the memory 804 are integrated.

[0144] The communication interface 806 is used in wired or wireless communication of signaling and / or data between a network node, access network, and / or UE. As illustrated, the communication interface 806 comprises port(s) / terminal(s) 816 to send and receive data, for example to and from a network over a wired connection. The communication interface 806 also includes radio front-end circuitry 818 that may be coupled to, or in certain embodiments a part of, the antenna 810. The radio front-end circuitry 818 comprises filters 820 and amplifiers 822. The radio front-end circuitry 818 may be connected to the antenna 810 and the processing circuitry 802. The radio front-end circuitry 818 may be configured to condition signals communicated between the antenna 810 and the processing circuitry 802. The radio front-end circuitry 818 mayreceive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 818 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of the filters 820 and / or the amplifiers 822. The radio signal may then be transmitted via the antenna 810. Similarly, when receiving data, the antenna 810 may collect radio signals which are then converted into digital data by the radio front-end circuitry 818. The digital data may be passed to the processing circuitry 802. In other embodiments, the communication interface 806 may comprise different components and / or different combinations of components.

[0145] In certain alternative embodiments, the network node 800 does not include separate radio front-end circuitry 818; instead, the processing circuitry 802 includes radio front-end circuitry and is connected to the antenna 810. Similarly, in some embodiments, all or some of the RF transceiver circuitry 812 is part of the communication interface 806. In still other embodiments, the communication interface 806 includes the one or more ports or terminals 816, the radio front-end circuitry 818, and the RF transceiver circuitry 812 as part of a radio unit (not shown), and the communication interface 806 communicates with the baseband processing circuitry 814, which is part of a digital unit (not shown).

[0146] The antenna 810 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 810 may be coupled to the radio front-end circuitry 818 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 810 is separate from the network node 800 and connectable to the network node 800 through an interface or port.

[0147] The antenna 810, the communication interface 806, and / or the processing circuitry 802 may be configured to perform any receiving operations and / or certain obtaining operations described herein as being performed by the network node 800. Any information, data, and / or signals may be received from a UE, another network node, and / or any other network equipment. Similarly, the antenna 810, the communication interface 806, and / or the processing circuitry 802 may be configured to perform any transmitting operations described herein as being performed by the network node 800. Any information, data, and / or signals may be transmitted to a UE, another network node, and / or any other network equipment.

[0148] The power source 808 provides power to the various components of the network node 800 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 808 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 800 with power for performing the functionality described herein. For example, the network node 800 may beconnectable to an external power source (e.g., the power grid or an electricity outlet) via input circuitry or an interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 808. As a further example, the power source 808 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

[0149] Embodiments of the network node 800 may include additional components beyond those shown in Figure 8 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and / or any functionality necessary to support the subject matter described herein. For example, the network node 800 may include user interface equipment to allow input of information into the network node 800 and to allow output of information from the network node 800. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 800.

[0150] Figure 9 is a block diagram of a host 900, which may be an embodiment of the host 616 of Figure 6, in accordance with various aspects described herein. As used herein, the host 900 may be or comprise various combinations of hardware and / or software including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 900 may provide one or more services to one or more UEs.

[0151] The host 900 includes processing circuitry 902 that is operatively coupled via a bus 904 to an input / output interface 906, a network interface 908, a power source 910, and memory 912. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 7 and 8, such that the descriptions thereof are generally applicable to the corresponding components of the host 900.

[0152] The memory 912 may include one or more computer programs including one or more host application programs 914 and data 916, which may include user data, e.g., data generated by a UE for the host 900 or data generated by the host 900 for a UE. Embodiments of the host 900 may utilize only a subset or all of the components shown. The host application programs 914 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), Moving Picture Experts Group (MPEG), VP9) and audio codecs (e.g., Free Lossless Audio Codec (FLAC), Advanced Audio Coding (AAC), MPEG, G.76), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers,wearable display systems, and heads-up display systems). The host application programs 914 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 900 may select and / or indicate a different host for Over-The-Top (OTT) services for a UE. The host application programs 914 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (DASH or MPEG-DASH), etc.

[0153] Figure 10 is a block diagram illustrating a virtualization environment 1000 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices, and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more Virtual Machines (VMs) implemented in one or more virtual environments 1000 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized. In some embodiments, the virtualization environment 1000 includes components defined by the O-RAN Alliance, such as an O-Cloud environment orchestrated by a Service Management and Orchestration Framework via an O-2 interface.

[0154] Applications 1002 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment 1000 to implement some of the features, functions, and / or benefits of some of the embodiments disclosed herein.

[0155] Hardware 1004 includes processing circuitry, memory that stores software and / or instructions executable by hardware processing circuitry, and / or other hardware devices as described herein, such as a network interface, input / output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 1006 (also referred to as hypervisors or VM Monitors (VMMs)), provide VMs 1008A and 1008B (one or more of which may be generally referred to as VMs 1008), and / or perform any of the functions, features, and / or benefits described in relation with some embodiments described herein. Thevirtualization layer 1006 may present a virtual operating platform that appears like networking hardware to the VMs 1008.

[0156] The VMs 1008 comprise virtual processing, virtual memory, virtual networking, or interface and virtual storage, and may be run by a corresponding virtualization layer 1006. Different embodiments of the instance of a virtual appliance 1002 may be implemented on one or more of the VMs 1008, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as Network Function Virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers and customer premise equipment.

[0157] In the context of NFV, a VM 1008 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 1008, and that part of the hardware 1004 that executes that VM, be it hardware dedicated to that VM and / or hardware shared by that VM with others of the VMs 1008, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 1008 on top of the hardware 1004 and corresponds to the application 1002.

[0158] The hardware 1004 may be implemented in a standalone network node with generic or specific components. The hardware 1004 may implement some functions via virtualization. Alternatively, the hardware 1004 may be part of a larger cluster of hardware (e.g., such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 1010, which, among others, oversees lifecycle management of the applications 1002. In some embodiments, the hardware 1004 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a RAN or a base station. In some embodiments, some signaling can be provided with the use of a control system 1012 which may alternatively be used for communication between hardware nodes and radio units.

[0159] Figure 11 shows a communication diagram of a host 1102 communicating via a network node 1104 with a UE 1106 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as the UE 612A of Figure 6 and / or the UE 700 of Figure 7), the network node (such as the network node 610A of Figure 6 and / or the network node 800 of Figure 8), and the host (such asthe host 616 of Figure 6 and / or the host 900 of Figure 9) discussed in the preceding paragraphs will now be described with reference to Figure 11.

[0160] Like the host 900, embodiments of the host 1102 include hardware, such as a communication interface, processing circuitry, and memory. The host 1102 also includes software, which is stored in or is accessible by the host 1102 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 1106 connecting via an OTT connection 1150 extending between the UE 1106 and the host 1102. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 1150.

[0161] The network node 1104 includes hardware enabling it to communicate with the host 1102 and the UE 1106. The connection 1160 may be direct or pass through a core network (like the core network 606 of Figure 6) and / or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.

[0162] The UE 1106 includes hardware and software, which is stored in or accessible by the UE 1106 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via the UE 1106 with the support of the host 1102. In the host 1102, an executing host application may communicate with the executing client application via the OTT connection 1150 terminating at the UE 1106 and the host 1102. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 1150 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 1150.

[0163] The OTT connection 1150 may extend via the connection 1160 between the host 1102 and the network node 1104 and via a wireless connection 1170 between the network node 1104 and the UE 1106 to provide the connection between the host 1102 and the UE 1106. The connection 1160 and the wireless connection 1170, over which the OTT connection 1150 may be provided, have been drawn abstractly to illustrate the communication between the host 1102 and the UE 1106 via the network node 1104, without explicit reference to any intermediary devices and the precise routing of messages via these devices.

[0164] As an example of transmitting data via the OTT connection 1150, in step 1108, the host 1102 provides user data, which may be performed by executing a host application. In someembodiments, the user data is associated with a particular human user interacting with the UE 1106. In other embodiments, the user data is associated with a UE 1106 that shares data with the host 1102 without explicit human interaction. In step 1110, the host 1102 initiates a transmission carrying the user data towards the UE 1106. The host 1102 may initiate the transmission responsive to a request transmitted by the UE 1106. The request may be caused by human interaction with the UE 1106 or by operation of the client application executing on the UE 1106. The transmission may pass via the network node 1104 in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 1112, the network node 1104 transmits to the UE 1106 the user data that was carried in the transmission that the host 1102 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1114, the UE 1106 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 1106 associated with the host application executed by the host 1102.

[0165] In some examples, the UE 1106 executes a client application which provides user data to the host 1102. The user data may be provided in reaction or response to the data received from the host 1102. Accordingly, in step 1116, the UE 1106 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input / output interface of the UE 1106. Regardless of the specific manner in which the user data was provided, the UE 1106 initiates, in step 1118, transmission of the user data towards the host 1102 via the network node 1104. In step 1120, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 1104 receives user data from the UE 1106 and initiates transmission of the received user data towards the host 1102. In step 1122, the host 1102 receives the user data carried in the transmission initiated by the UE 1106.

[0166] One or more of the various embodiments improve the performance of OTT services provided to the UE 1106 using the OTT connection 1150, in which the wireless connection 1170 forms the last segment. More precisely, the teachings of these embodiments may improve the e.g., data rate, latency, power consumption, etc. and thereby provide benefits such as e.g., reduced user waiting time, relaxed restriction on file size, improved content resolution, better responsiveness, extended battery lifetime, etc.

[0167] In an example scenario, factory status information may be collected and analyzed by the host 1102. As another example, the host 1102 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 1102 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controllingtraffic lights). As another example, the host 1102 may store surveillance video uploaded by a UE. As another example, the host 1102 may store or control access to media content such as video, audio, VR, or AR which it can broadcast, multicast, or unicast to UEs. As other examples, the host 1102 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing, and / or transmitting data.

[0168] In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency, and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1150 between the host 1102 and the UE 1106 in response to variations in the measurement results. The measurement procedure and / or the network functionality for reconfiguring the OTT connection 1150 may be implemented in software and hardware of the host 1102 and / or the UE 1106. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 1150 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or by supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 1150 may include message format, retransmission settings, preferred routing, etc.; the reconfiguring need not directly alter the operation of the network node 1104. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency, and the like by the host 1102. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 1150 while monitoring propagation times, errors, etc.

[0169] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions, and methods disclosed herein. Determining, calculating, obtaining, or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and / or performing one or more operations based on theobtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box or nested within multiple boxes, in practice computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

[0170] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer- readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hardwired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device but are enjoyed by the computing device as a whole and / or by end users and a wireless network generally.

Claims

CLAIMS 1. A method performed by a User Equipment, UE, (700) the method comprising: determining (100) a first codebook based on signaling from a network node (800); determining (102) a first index in a first index group based at least in part on the first codebook; determining (104) a second index in a second index group based on a set of pre-defined codebooks; and reporting (106) the first index and the second index to the network node (610) as part of a CSI report.

2. The method of claim 1 further comprising reporting subindices of the first index to the network node (610) as part of a CSI report.

3. The method of any of wherein the first index is an index i1for a conversion precoder W1and the second index is index i2 for a tuning precoder W2.

4. The method of any of claims 1-3 wherein the set of predefined codebooks includes codebooks from a standard specification.

5. The method of any of claims 1-4 further comprising receiving a first codebook configuration signaling from a network node and determining a first codebook based on the first codebook configuration signaling.

6. The method of claim 5 wherein the first codebook configuration signaling indicates either that the user equipment is to be signaled the first codebook or that the user equipment is to use a standardized codebook as the first codebook.

7. The method of claim 6 wherein the first codebook configuration signaling is a flag parameter, optionally configured either as part of CSI report configuration or a codebook configuration.

8. The method of any of claims 1-4 further comprising receiving the first codebook from the network node.

9. The method of any of claims 1-4, further comprising one of: using the first codebook for CSI computation, if the user equipment receives the first codebook from the network node; or using a codebook specified by a standard if the user equipment does not receive a first codebook from the network node.

10. The method of any of claims 1-9, wherein a sub-structure of the first codebook is selected from a set of predefined codebooks and a complementary structure is selected by the network node and signaled to the user equipment.

11. The method of any of claims 3-10, wherein the W1precoder has a block diagonal structure: ^^^ ൌ ^^^^0 integer, wherein, optionally, one or more^^^^^^ are constructed as normalized vectors; ^^^^^^ are constructed so that the first element ^^^^^^ (0) is always a constant; and / or vector elements ^^^^^^ ^^^^ , ^^ ൌ 0, .. ,^^ െ 1,0, .. , ^^ െ 1, ^^ ൌ 1,2 are quantized, optionally,as ^^^^^^ ^^^^ ∈ ^^^^^^ఝ^ and, optionally, a plurality of quantization points are given as, ^^^ ൌ1 and ^^ ∈ ^^^^^⁄ 4 , ^^ ൌ 0, .. ,7^.

12. The method of any of claims 1-11, wherein the first codebook is a parameterized codebook, wherein, optionally, one or more of the following apply: the parametrized codebook is signaled to the user equipment from the network; one or more parameters associated for the parametrized codebook are signaled to the user equipment from the network; one or more parameters for a set of uncorrelated 1-D beams along a first dimension, such as an x-dimension, and / or one or more parameters for a set of uncorrelated 1-D beams along a first dimension, such as a y-dimension, are signaled to the user equipment from the network, wherein, optionally, whenever only one set of the one or more parameters from one of the first and second dimensions are signaled to the user equipment, the remaining set of one or more parameters for the other dimension is selected from a combination of one or more pre-defined vectors or matrices each one of one or more vectors in the first codebook or one or more vectors whose cross product is a vector in the first codebook, are a linear combination of one or more predefined DFT matrices or vectors using a set of coefficients having amplitudes and phases. wherein, optionally, one or more of the following apply: the coefficients are signaled by the network node to the UE; the amplitudes of the coefficients in the linear combination are quantized using Mamp bits and / or are predefined in standard specifications, wherein, optionally, Mampis a per cell value and different cells may have different values; the phases of the coefficients in the linear combination are quantized using Mphase bits and / or are predefined in standard specifications, wherein, optionally, Mphaseis a per cell value and different cells may have different values; and / or a selection of predefined DFT matrices out of the total number of predefined DFT matrices in the linear combinations are signaled to the user equipment by the network node, wherein, optionally, the selection can be indicated by either one of a bitmap or a combinatorial indicator; and / or the first codebook configuration is per cell, with different first codebook configurations allowable for different cells.

14. The method of claim 13 wherein the first index i1 has two subindices i1,1 and i1,2 signalled, wherein subindex i1,1points to a network node configured codebook, such as a fully parametrized codebook, and subindex i1,2 point to to a standardized codebook , such as a codebook of vectors, such as DFT vectors.

15. A method performed by a network node (800), the method comprising: sending (200) to a user equipment (700) signaling that enables determination of a first codebook based on signaling from the network; and receiving (202) a CSI report comprising a first index and a second index, wherein the first index is in a first index group and is based at least in part on the first codebook and the second index is in a second index group and is based on a set of pre-defined codebooks.

16. The method of claim 15 wherein the first index is an index i1for a conversion precoder W1and the second index is index i2 for a tuning precoder W2.

17. The method of any of claims 15-16 wherein the set of predefined codebooks includes codebooks from a standard specification.

18. The method of any of claims 15-17 further comprising sending a first codebook configuration signaling to the user equipment indicative of a first codebook.

19. The method of claim 18 wherein the first codebook configuration signaling indicates either that the user equipment is to be signaled the first codebook or that the user equipment is to use a standardized codebook as the first codebook.

20. The method of claim 19 wherein the first codebook configuration signaling is a flag parameter, optionally configured either as part of CSI report configuration or a codebook configuration.

21. The method of any of claims 15-17 further comprising sending the first codebook to the user equipment.

22. The method of any of claims 15-21, wherein a sub-structure of the first codebook is selected from a set of predefined codebooks and a complementary structure is selected by the network node and signaled to the user equipment.

23. he method of any of claims 16-22, wherein the W1precoder has a block diagonal structure: ^^ ൌ ^^^^0 ^0 ^^ଶ൨ integer, wherein, optionally, one or more^^^^^^ are constructed as normalized vectors; ^^^^^^ are constructed so that the first element ^^^^^^ (0) is always a constant; and / or vector elements ^^^^^^ ^^^^ , ^^ ൌ 0, .. ,^^ െ 1,0, .. , ^^ െ 1, ^^ ൌ 1,2 are quantized, optionally,as ^^^^^^ ^^^^ ∈ ^^^^^^ఝ^ and, optionally, a plurality of quantization points are given as, ^^^ ൌ1 and ^^ ∈ ^^^^^⁄ 4 , ^^ ൌ 0, .. ,7^.

24. The method of any of claims 15-23, wherein the first codebook is a parameterized codebook, wherein, optionally, one or more of the following apply: the parametrized codebook is signaled to the user equipment from the network; one or more parameters associated for the parametrized codebook are signaled to the user equipment from the network; one or more parameters for a set of uncorrelated 1-D beams along a first dimension, such as an x-dimension, and / or one or more parameters for a set of uncorrelated 1-D beams along a first dimension, such as a y-dimension, are signaled to the user equipment from the network, wherein, optionally,whenever only one set of the one or more parameters from one of the first and second dimensions are signaled to the user equipment, the remaining set of one or more parameters for the other dimension is selected from a combination of one or more pre-defined vectors or matrices each one of one or more vectors in the first codebook or one or more vectors whose cross product is a vector in the first codebook, are a linear combination of one or more predefined DFT matrices or vectors using a set of coefficients having amplitudes and phases. wherein, optionally, one or more of the following apply: the coefficients are signaled by the network node to the UE; the amplitudes of the coefficients in the linear combination are quantized using Mamp bits and / or are predefined in standard specifications, wherein, optionally, Mampis a per cell value and different cells may have different values; the phases of the coefficients in the linear combination are quantized using Mphase bits and / or are predefined in standard specifications, wherein, optionally, Mphase is a per cell value and different cells may have different values; and / or a selection of predefined DFT matrices out of the total number of predefined DFT matrices in the linear combinations are signaled to the user equipment by the network node, wherein, optionally, the selection can be indicated by either one of a bitmap or a combinatorial indicator; and / or the first codebook configuration is per cell, with different first codebook configurations allowable for different cells.

25. A User Equipment, UE, (700) comprising processing circuitry (702) and memory (704), the memory (704) comprising instructions to cause the UE (700) to: determine a first codebook based on signaling from the network; determine a first index in a first index group based at least in part on the first codebook; determine a second index in a second index group based on a set of pre-defined codebooks; and report to the network node a CSI report.

26. The UE (700) of claim 25 further operable to implement the features of any of claims 2-12.

27. A computer-readable medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 1 to 14.

28. A network node (800) comprising processing circuitry (802) and memory (804), the memory (804) comprising instructions to cause the network node (800) to: send to a user equipment signaling that enables determination of a first codebook based on signaling from the network; and receive a CSI report, wherein a first index in a first index group based at least in part on the first codebook and a second index in a second index group is based on a set of pre-defined codebooks.

29. The network node (800) of claim 28 further operable to implement the features of any of claims 16-24.

30. A computer-readable medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 15 to 24.

Images