Reporting channel state information

Abstract

A method performed by a user equipment (UE) for reporting channel state information (CSI) is provided. The method includes transmitting (1600) an indication that the UE supports a first scheme for a codebook in which a candidate precoder includes a set of beams that are orthogonal to each other in at least one of a first dimension and a second dimension. The method further includes receiving (1602) a CSI report configuration for the codebook; and identifying (1606) a precoding matrix indicator (PMI) from a subset of candidate beam combinations in the codebook allowed by the first scheme. The method further includes transmitting the PMI based on the CSI report configuration.

Description

Reporting Channel State Information TECHNICAL FIELD

[0001] The present disclosure relates generally to methods performed by a user equipment (UE) for reporting channel state information (CSI), and related methods and devices.BACKGROUND

[0002] A core component of the fifth generation (5G) wireless network or New Radio (NR) is the support of multiple-input multiple-output (MIMO) antenna deployments and MIMO related techniques such as spatial multiplexing. Spatial multiplexing can be used to increase data rates in favorable channel conditions. CSI reporting can include CSI parameters such as a precoding matrix indicator(s), which specifies a unique precoding matrix in a codebook for a given number of symbol streams used in spatial multiplexing.SUMMARY

[0003] There currently exist certain challenges. A PMI search at a UE can be quite complex, as the UE may need to evaluate all possible beam candidates and build their extended sets. For example, the UE may need to evaluate all possible beam combinations for up to 4 beams that are orthogonal in either a first, Nltdimension or a second, N2, dimension. The number of possible beam combinations can be significant, e.g., millions or billions of possible beam combinations. Moreover, from a UE perspective, it may be desirable to use a currently implemented PMI search process, such as Scheme A in Release-19 (Rel-19) Third Generation Partnership Project (3GPP) standards. However, a full blown implementation of Scheme A for ranks greater than 4 can be too computationally costly. In addition, it was agreed in 3GPP meeting RAN1#117 that a Rel-19 capable UE can support two different CSI report delay capabilities, one more strict using legacy Release 15 values, and another less strict using larger values. However, such a scenario may increase the CSI timeline , which in turn may result in throughput performance deterioration, especially in high mobility scenarios for example.

[0004] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges.

[0005] Some embodiments provide a method by a UE for reporting CSI. The method includes transmitting an indication that the UE supports a first scheme for a codebook in which a candidate precoder includes a set of beams that are orthogonal to each other in at least one of a first dimensionand a second dimension; and receiving a CSI report configuration for the codebook. The method further includes identifying a precoding matrix indicator (PMI) from a subset of candidate beam combinations in the codebook allowed by the first scheme; and transmitting the PMI based on the CSI report configuration.

[0006] Other embodiments provide a UE. The UE comprises processing circuitry, and memory coupled with the processing circuitry. The memory includes instructions that when executed by the processing circuitry causes the UE to perform operations. The operations include to transmit an indication that the UE supports a first scheme for a codebook in which a candidate precoder includes a set of beams that are orthogonal to each other in at least one of a first dimension and a second dimension; and receive a CSI report configuration for the codebook. The operations further include to identify a PMI from a subset of candidate beam combinations in the codebook allowed by the first scheme; and to transmit the PMI based on the CSI report configuration.

[0007] Some embodiments include a non-transitory computer readable medium including program code to be executed by processing circuitry of a UE. Execution of the program code causes the program code to perform operations. The operations include to transmit an indication that the UE supports a first scheme for a codebook in which a candidate precoder includes a set of beams that are orthogonal to each other in at least one of a first dimension and a second dimension; and receive a CSI report configuration for the codebook. The operations further include to identify a PMI from a subset of candidate beam combinations in the codebook allowed by the first scheme; and to transmit the PMI based on the CSI report configuration.

[0008] Based on inclusion of a codebook selection scheme in which a candidate precoder is composed of a set of beams where the beams are orthogonal to each other in at least one of two dimensions (e.g., Ni or ^ / vertical or horizontal), PMI search complexity at the UE may be reduced. Moreover, reduction of PMI computation time, may allow the UE to report CSI feedback faster and potentially avoid loss in performance caused by a larger CSI report computation time.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this application, illustrate certain non- limiting embodiments of the present disclosure. In the drawings:

[0010] Figure 1 is a block diagram illustrating an example of spatial multiplexing;

[0011] Figure 2 is a schematic drawing of a two-dimensional antenna array of dual-polarized antenna elements;

[0012] Figure 3 is schematic diagram of an example of a resource element (RE) allocation for a 12-port CSI-reference signal (CSI-RS) in NR;

[0013] Figure 4 is a block diagram of an example of second beam candidates for Rel-19 Scheme A for ranks 5-8;

[0014] Figure 5 is a block diagram of an example of third beam candidates for Rel- 19 Scheme A for ranks 5-8;

[0015] Figure 6 is a block diagram of an example of fourth beam candidates for Rel-19 Scheme A for ranks 5-8;

[0016] Figure 7 is a block diagram of an example of second, third, and fourth beam candidates for Scheme B ;

[0017] Figure 8 is a block diagram of an example of an improved implementation according to a reduced set of extended beams based on 3GPP legacy Release 15 codebook design or Rel-19 for ranks less than or equal to 4 according to some embodiments;

[0018] Figure 9 is a block diagram of an example of a simplified set of discrete Fourier transform (DFT) beam candidates that are orthogonal in both N±and N2dimensions according to some embodiments;

[0019] Figure 10 is a block diagram of an example of a simplified set of DFT beam candidates that are orthogonal in either a first or second dimension according to some embodiments following legacy offsets according to some other embodiments;

[0020] Figure 11 is a block diagram of an example in which the UE selects a simplified set of DFT beam candidates based on a metric by limiting the selection of beams to be of beams that are orthogonal in both N±and N2dimensions according to some embodiments;

[0021] Figure 12 is a block diagram of an example of a simplified set of DFT beam candidates based on a metric and that are orthogonal in either N±or N2dimensions or in both N±and N2dimensions according to some embodiments;

[0022] Figures 13 - 15 are block diagrams of an example of a sequential implementation with a strongest DFT beam as first selected beam, in which for each resulting set, a strongest beam is selected according to some embodiments;

[0023] Figure 16 is a flow chart illustrating operations of a UE according to some embodiments;

[0024] Figure 17 is a block diagram of a communication system in accordance with some embodiments;

[0025] Figure 18 is a block diagram of UE according to some embodiments;

[0026] Figure 19 is a block diagram of a network node in accordance with some embodiments; and

[0027] Figure 20 is a block diagram of a virtualization environment in accordance with some embodiments.DETAILED DESCRIPTION

[0028] 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, in which examples of embodiments of the present disclosure are shown. Inventive concepts may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. Components from one embodiment may be tacitly assumed to be present / used in another embodiment.

[0029] With respect to codebook-based precoding, multi-antenna techniques can significantly increase the data rates and reliability of a wireless communication system. 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 may be referred to as MIMO.

[0030] A core component of the fifth Generation (5G) wireless network or New Radio (NR) is the support of MIMO antenna deployments and MIMO related techniques such as spatial multiplexing. Spatial multiplexing can be used to increase data rates in favorable channel conditions. Figure 1 shows an example of spatial multiplexing. An information carrying symbol vector 5 is multiplied by an NTx r precoding matrix or precoder W, which serves to distribute the transmit energy in a subspace of the NTdimensional vector space. The precoding matrix is typically selected from a codebook of possible precoding matrices, and typically indicated by means of a PMI, which specifies a unique precoding matrix in the codebook for a given number of symbol streams. The r symbols in s each correspond to a MIMO layer and r may be referred to as the transmission rank, which equals to the number of columns of the precoder W. In this way, spatial multiplexing is achieved since multiple symbols can be transmitted simultaneously over the same time / frequency resource element (RE). The number of symbols r is typically adapted to suit the current channel properties.

[0031] NR uses Orthogonal Frequency Division Multiplexing (OFDM) in downlink (DL). The received NRx 1 vector ynat a UE on a certain RE can be expressed as:where enis a receiver noise / interference vector. The precoder W can be constant over frequency (e.g., wideband), or frequency selective (e.g., per subband).

[0032] The precoder W can be chosen to match the characteristics of the NRx NTMIMO channel matrix Hn, resulting in so-called channel dependent precoding. This also may be referred to as closed-loop precoding.

[0033] In closed-loop precoding, the UE feeds back recommendations on a suitable precoder to a network node (e.g., a gNodeB (gNB)) in the form of a PMI based on downlink channel measurements. For that purpose, the UE is configured with a CSI report configuration including CSI-RS for channel measurements and a codebook of candidate precoders. In addition to precoders, the feedback also may include a rank indicator (RI) and one or two channel quality indicators (CQIs). RI, PMI and CQI may be part of a CSI feedback. 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 physical resource blocks (PRBs) ranging between 4-32 PRBs depending on the band width part (BWP) size.

[0034] Given the CSI feedback from the UE, the network node (e.g., 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).

[0035] Two-dimensional antenna arrays are widely used and such antenna arrays can be described by a number of antenna ports, ^, in a first dimension (e.g., the horizontal dimension), a number of antenna ports, N2, in the second dimension perpendicular to the first dimension (e.g., the vertical dimension), and a number of polarizations Np. The total number of antenna ports is thus N = N1N2Np. The concept of an antenna port is non-limiting in the sense that it can refer to any virtualization (e.g., linear mapping) to the physical antenna elements. For example, pairs of physical antenna elements can be fed the same signal, and hence share the same virtualized antenna port.

[0036] An example of a 4 x 4 (i.e., N x N2,) array with dual-polarized antenna elements (i.e., Np= 2 ) is illustrated in Figure 2. As shown in Figure 2, this example shows a two-dimensional antenna array of dual -polarized antenna elements (Np= 2), with N±= 4 horizontalantenna elements in a first direction 1, and N2= 4 vertical antenna elements in a second direction m.

[0037] Precoding may be interpreted as multiplying the signal to be transmitted by a set of beamforming weights on the antenna ports prior to transmission. A typical approach is to tailor the precoder to the antenna form factor, e.g., taking into account N1, N2and Npwhen designing the precoder codebook.

[0038] For CSI measurement and feedback, CSI-RS are defined. For example, a CSI-RS is transmitted on an antenna port at a gNB and is used by a UE to measure DL channel between the antenna port and each of the UE’s receive antenna ports. The transmit antenna ports are also referred to as CSI-RS ports. In an example, a supported number of CSI-RS ports in NR are { 1,2,4,8,12,16,24,32}. 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 this purpose may be referred to as Non-Zero Power (NZP) CSI-RS.

[0039] 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 RE allocation for 12 antenna ports, where 1 RE per RB per port is shown.

[0040] Interference measurement resource (IMR) is also defined in NR for a UE to measure interference. In an example, an IMR resource contains 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. Furthermore, a UE in NR may be configured to measure interference based on one or multiple NZP CSI-RS resource.

[0041] 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 can feed back a CSI report.

[0042] Each CSI reporting setting can contain at least one or more of the following information:• A CSI-RS resource setting for channel measurement• An IMR resource set for interference measurement• Optionally, a CSI-RS resource set for interference measurement• Time-domain behavior, e.g., periodic, semi-persistent, or aperiodic reporting• Frequency granularity, e.g., 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, e.g., type I or II, and codebook subset restriction• Measurement restriction• Subband size. For example, one out of two possible subband sizes may be indicated, and the value range may depend on the bandwidth of the bandwidth part (BWP). One CQI / PMI (if configured for subband reporting) may be fed back per subband.

[0043] An example type of precoding is to use a DFT-precoder, where the precoder vector used to precode a single-layer transmission using a single-polarized uniform linear array (ULA) with N antennas is defined as:where k = 0,1, ... ON — 1 is the precoder index and 0 is an integer oversampling factor. ukalso may be referred to as an one-dimension (1-D) DFT vector with beam index k. If ULA is along the horizontal dimension, for example, each DFT vector points to an azimuth direction. If ULA is along the vertical dimension, for example, each DFT vector points to an elevation direction. Each precoder corresponds to a DFT vector.

[0044] A corresponding precoder vector for a two-dimensional uniform planar / rectangular array (UP A) with N antenna ports in one dimension and N2antenna ports in another dimension can be defined as specified in 3GPP TS 38.214 V17.6.0:>

[0045] In the above, O and O2are the over sampling factors in the two dimensions associated with N and N2, respectively. Moreover, umis a DFT vector along the N2dimension of the array, and which is also referred to as two-dimensional (2-D) DFT vector characterized by two beam indicesone in each dimension, is formed by the Kronecker product of umand v where vtis a DFT vector along the N dimension. As such, each such vector vt m( / = 0, ... , N^ O — 1; m = 0, ... , N2O2— 1) corresponds to a 2-D DFT vector.

[0046] In an example uniform regular planar / rectangular array configuration, the N dimension is along the horizontal direction of the array and the N2dimension is along the vertical direction of the array. In an alternative example configuration, the N±dimension is along the vertical direction of the array and the N2dimension is along the horizontal direction of the array.

[0047] Extending the 2-D DFT vectors for dual-polarized UPA may then be done as:< is a co-phasing factor that may be selected from M-PSK alphabet such as QPK with n = 0, 1, 2, 3, and PCSI-RS isthe number of CSI-RS ports. This is the codebook for single layer CSI report with PCSI-RS ports.

[0048] A precoder matrix for multi-layer transmission may be created by appending columns of 2-D DFT vectors. An example for 2-layer precoder matrix is given as:

[0049] Such DFT-based precoders are used for instance in NR Type I CSI feedback, where each layer is associated with a 2-D DFT vector. The NR Type I CSI feedback including such DFT-based precoders is defined in clause 5.2.2.2.1 of 3GPP TS 38.214 V18.0.0, for example.

[0050] A Type I CSI codebook for 2-layers is shown below in Table 1, as specified in 3GPP TS 38.214 VI 8.2.0. In this codebook, the 2-D DFT vector vt mfor the first spatial layer (or transmission layer) is given by the indices i1and i12. However, the 2-D DFT vectorm< is predetermined in the 3GPP specification by adding offsets k and k2to indices i1 ±and i12, respectively. That is, Vp,m' is determined such that I' = i1 ±+ k and m' = i1 2+ k2. Up to four possible values for offsets k and k2can be selected by index i1 3as shown in Table . Moreover, index i2is responsible for the inter-polarization co-phasing, which is determined according to the elements of a M-PSK constellation alphabet, with M = 4.

[0051] Table 1. Codebook for 2-layer CSI reporting using antenna ports 3000 to 2999+PCSI-RS (reproduced from Table 5.2.2.2.1-6 of 3GPP TS 38.214 V18.2.0):

[0052] Table 2. Mapping from i13to k±and k2for 2-layer CSI reporting (reproduced from Table 5.2.2.2.1-3 of 3GPP 38.214 V18.2.0):> > >

[0053] A Type I CSI codebook for 5-layers is given below in Table 3, as specified in 3GPP TS 38.214 VI 8.2.0. In this codebook, the 2-D DFT vector vt mused for the first and second spatial layers (or transmission layers) is given by indices. However, the 2-D DFT vector i ,m' (used for the 3rd and 4th spatial layers) is fixed in the 3GPP specification. For instance, when N2>is determined such that I' = i1 ±+ O and m' = i12. Similarly, the 2-D DFT vector(used for the 5th spatial layer) is fixed in the 3GPP specification. For instance, when N2>is determined such that I" = i1 ±+ O and m" = i12+ O2.

[0054] Table 3. Codebook for 5-layer CSI reporting using antenna ports 3000 to 2999+PCSI-RS (reproduced from Table 5.2.2.2.1-9 of 3GPP 38.214 V18.2.0):>>"""" > "

[0055] As there may be interest in increasingly large network node (e.g., gNB) antenna arrays, for the 3GPP Release 19 MIMO work item it was agreed to specify support for up to 128 CSI-RS ports targeting frequency range 1 (FR1). Thus, to try to achieve this goal, enhancements to Type-I Single Panel Mode 1 as well as for some Type-II codebooks were agreed.

[0056] For the Type-I codebook, it was agreed to support up to a total of 128 CSI-RS ports across all resources, assuming legacy CSI-RS resources with up to 32 CSI-RS ports each. These enhancements were agreed to be based on extension of the current legacy codebooks.

[0057] During the 3GPP RAN1#116 meeting , it was agreed to extend the legacy NltN2values with the respective port layouts to support more than 32 CSI-RS ports as shown, for example in Table 4 below showing new port layouts and NltN2values for Release-19:

[0058] During the 3GPP RAN1#117 meeting , two new codebook schemes for CSI-RS Type-I were agreed. These schemes are further split according to the maximum rank, for ranks up to 4 and for ranks between 5 and 8.

[0059] The first scheme (also referred to as Scheme A) is aimed at low complexity and low overhead, to allow for fast commercialization of UEs supporting feedback-based CSI reporting of larger number of antenna ports at the network node (e.g., gNB).

[0060] For Scheme A up to rank 4, an extension of the Rel-15 legacy Type I codebook was agreed. This extension is achieved by introducing new N1, N2values in Table 4 (shown above). As such, no change to the legacy codebook structure was performed. The codebooks are still determined according to 3GPP specifications, following legacy i1, i1 2, ,3, and i2reporting as specified in 3GPP TS 38.214 VI 8.2.0 section 5.2.2.2.1.

[0061] In addition to supporting new N1, N2values, the new Release-19 Type-I Single Panel codebook for Scheme A, for ranks 3-4 may reuse the codebook structure of the legacy codebook for PCSI-RS < 16 for any number of ports, e.g. the case when PCSI-RS=48, 64, 128 , such that a unified structure for all layers up to 4 is considered.

[0062] For Scheme A for ranks between 5-8, a new codebook structure has been agreed, where beam selection does not depend on the index i13anymore, nor does it need to be constrained to neighboring beams with fixed k , k2offset values. Instead, this new structure assumes that beams can be selected over the entire network node (e.g., gNB) array, as long as they are orthogonal either in the N±or N2dimensions with respect to the previously selected beam(s).

[0063] Figure 4 shows an example of second (2nd) beam candidates for Release 19 Scheme A for ranks 5-8. In the example in Figure 4, the oversampled DFT beams 404 of a N = 8, N2= 4 array structure is considered and assuming oversampling factors O = O2= 4. For a given first beam 400 selected, the possible Rel-19 2nd beam candidates 402 for Scheme A ranks 5-8 aregiven, which correspond to the orthogonal beams in either the N±or N2dimensions with respect to the first beam 400.

[0064] Figure 5 shows an example of third beam candidates for Rel-19 Scheme A for ranks 5-8. In this example, a set of possible Rel-19 candidate 3rd beams 500 are shown after the selection of the 1st beam 400 and 2nd beams 402. It is noted that the candidate 3rd beam sets 500 are built according to the intersection of the orthogonal candidate beams with respect to both the 1stbeam 400 and 2nd selected beams 402. Figure 6 shows examples of a 4th beam candidate set 600, for Rel-19 Scheme A for ranks 5-8, after the selection of the first 3 beams 400, 402, 500.

[0065] Another scheme that was agreed in 3GPP is Scheme B, which is aimed more towards high flexibility and independent beam selection, while there may be an expense of higher overhead.

[0066] For up to rank 4, it was agreed that Scheme B supports independent DFT beams per layer; or, in other words, up to 4 DFT beams for ranks up to 4. In addition, Scheme B aims at having independent inter-polarization co-phasing factors per layer.

[0067] Figure 7 shows an example of possible 2nd, 3rd, and 4th beam candidates after the first beam 400 is selected. In this Scheme B case, the set of possible 2nd, 3rd, and 4th beam candidates 402 is formed such that the candidate beams must be orthogonal in both N±and N2dimensions according to all other previously selected beams. The only restriction is that a single DFT beam can be reused to transmit a maximum of two layers. Therefore, according to the codebook structure of Rel-19 scheme B ranks 1^4, the minimum and maximum number of DFT beams that can be selected for a 4 layer transmission are two and four, respectively.

[0068] For Scheme B for ranks greater than 4 the same structure as for ranks up to 4 was agreed. The only difference is in terms of the total number of beams. Instead of considering one independent DFT beam per layer, for ranks larger than 4 it was agreed that a single beam is shared among two layers. For ranks 5-6 it was agreed that 3 beams are selected, whereas for ranks 7-8, the 4 best beams are selected. In addition, inter-polarization co-phasing factors are also repeated with a fixed rotation of n to achieve inter-layer orthogonality among repeated beams in the two common layers. Moreover, when the rank is an odd number, the least powerful beam is not repeated and is designated as an orphan beam, and it also has an independent co-phasing factor.

[0069] A challenge that needs to be solved is that with the newly agreed Scheme A for ranks greater than 4, PMI search at the UE can become quite complex, as the UE needs to evaluate all possible beam candidates and / or beam candidate combinations and build their extended sets (e.g., evaluate all possible beam combinations for up to 4 beams that are orthogonal in either the N or N2dimensions). Moreover, from a UE perspective, it may be desirable to keep the currentlyimplemented PMI search algorithm, and hence, a full blown implementation of Scheme A for ranks greater than 4 can be too costly. Moreover, it was also agreed in the 3GPP RAN1#117 meeting that a Rel-19 capable UE can support two different CSI report delay capabilities, one more strict, using legacy Release 15 values and another looser, using larger values. However, by increasing the CSI timeline, downlink throughput performance deteriorates especially in high mobility scenarios.

[0070] Thus, even if Scheme A for ranks greater than 4 was already agreed in NR Rel-19, it may be desirable to implement an improved version of Scheme A to avoid complexity or to reduce computation delay and avoid loss in downlink throughput performance. For example, a UE may indicate support for Scheme A for ranks greater than 4; however, the UE may perform a PMI search for only a subset of beam candidates to reduce UE complexity.

[0071] In a further example, for a UE measuring on / receiving more than 32 CSI-RS ports transmitted by a network node and equipped with more than 4 receive (Rx) chains that is configured to receive more than 4-layer transmission and that indicates support for Scheme A for ranks greater than 4, it may be desirable to have methods of implementation of an improved version of the agreed Scheme A for ranks greater than 4 to reduce UE complexity and PMI search computation.

[0072] Figure 16 is a flow chart illustrating operations of a UE according to some embodiments. As shown, some embodiments are directed to a method performed by a UE for reporting CSI. In block 1600, the method includes transmitting an indication that the UE supports a first scheme for a codebook in which a candidate precoder includes a set of beams that are orthogonal to each other in at least one of a first dimension and a second dimension. In block 1602, the method further includes receiving a CSI report configuration for the codebook; and, in block 1606, identifying a PMI from a subset of candidate beam combinations in the codebook allowed by the first scheme. In block 1608, the method further includes transmitting the PMI based on the CSI report configuration.

[0073] As used herein, the term “scheme” includes, without limitation a process or a method such as Scheme A, Scheme B, etc.

[0074] Thus, in some examples, the UE only identifies PMIs from a subset of all candidate beam combinations allowed by the first scheme, since the scheme by itself only allows UE to identify a subset of all beams in the codebook.

[0075] In an example, a UE transmits in capability signaling support for a codebook method in which a candidate precoder is composed of a set of beams where the beams are orthogonal to each other in at least one of the two dimensions (e.g., Ni or N2 / vertical or horizontal). Examplesof such a codebook include NR Release 19 Type-I single panel codebook Scheme A for ranks greater than 4. Further, in this example, the UE receives a CSI report configuration for the codebook; and the UE only evaluates a subset of the candidate beam combinations allowed in the codebook. Further, in this example, the UE transmits a PMI from the evaluated subset of candidate beam combinations in a CSI report.

[0076] In some embodiments, identifying (operation 1606) includes searching the subset of candidate beam combinations according to a first oversampling factor in the first dimension and to a second oversampling factor in the second dimension. For example, the UE is further configured to search DFT beams according to oversampling factorsO2. which correspond to oversampling factors in the N±and N2dimensions.

[0077] The term “oversampled DFT beams” alternatively may be referred to as ‘2D DFT vector’ or ‘2D DFT beam’, ‘spatial domain basis vector’, ‘DFT beam,’ or even ‘oversampled DFT beam’ .

[0078] In some embodiments, the subset of candidate beams is according to supported candidate beam combinations of the first scheme for the codebook for a rank of less than or equal to 4 using a first offset and a second offset when the UE is configured for a rank larger than 4. For example, the subset of evaluated candidate beam combinations is according to the supported candidate beam combinations of NR Release 19 Type-I single panel codebook Scheme A for rank smaller than or equal to 4, usingk2offsets.

[0079] In other embodiments, identifying (operation 1606 in Figure 16) includes searching the subset of candidate beam combinations from the codebook for a rank of less than or equal to 4, wherein respective candidate beams in the subset have a first offset and a second offset with respect to a previously selected beam.

[0080] In other embodiments, the subset of candidate beam combinations include supported candidate beam combinations of a second scheme for the codebook for ranks 5 to 8, using a first offset and a second offset. For example, the subset of evaluated candidate beam combinations is according to the supported candidate beam combinations of NR Release 15 Type-I single panel codebook for ranks 5-8, using k2offsets.

[0081] In some embodiments, the subset of candidate beam combinations include supported candidate beam combinations of a second scheme for the codebook. For example, the subset of evaluated candidate beam combinations is according to the supported candidate beam combinations of NR Release 19 Type-I single panel codebook Scheme B than 4.

[0082] In some embodiments, the subset of candidate beam combinations include a subset of a plurality of beam groups, and the method further includes optionally filtering (operation 1604)the plurality of beam groups based on a metric to identify the subset of candidate beam combinations that satisfy the metric; and identifying (operation 1606) includes searching the subset of candidate beam combinations that satisfy the metric to identify at least one candidate beam for the PMI. For example, the UE performs an optional first step that filters beam groups and after determining which groups are the best according to a certain metric (such as received signal power), the UE searches for candidate beam combinations that are orthogonal in either N or N2dimensions and reports a subset of candidate beam combinations from Scheme A for ranks greater than 4.

[0083] In some embodiments, identifying (operation 1606) includes searching the subset of candidate beam combinations that satisfy the metric to identify at least one candidate beam that is orthogonal in both the first dimension and the second dimension, and transmitting (operation 1608) includes transmitting the at least one candidate beam from a second scheme for the codebook. For example, the UE optionally performs a first step that filters beam groups and after determining which groups are the best according to a certain metric (such as received signal power), the UE searches for candidate beam combinations that are orthogonal in both N±and N2dimensions and reports a subset of candidate beam combinations from the NR Release 19 Type-I single panel codebook Scheme B.

[0084] In some embodiments, identifying (operation 1606) includes performing a sequential beam search to select a strongest beam among the subset of candidate beam combinations as a first beam, wherein a remainder of the subset of candidate beam combinations include a resulting set of beam candidate combinations for a next beam, and selecting a strongest beam from the resulting set of beams candidate combinations as the next beam. In another embodiment, the method further optionally includes repeating the identifying (operation 1606) for a subsequent next beam. For example, the UE performs a sequential beam search, in which it selects the strongest beam among all beam candidates as the first beam, and then selects the subsequent beams as the strongest beam from each resulting subset of beam candidates in each step.

[0085] Some examples as follows include an improved implementation according to a first scheme, such as Scheme A for ranks up to 4 or 3 GPP legacy Release 15 for example.

[0086] In one example, the selection of second, third and fourth DFT beams are constrained from the full set of possible beam candidates that are orthogonal to the selected beams according to Scheme A for ranks greater than 4 either in the Ni or N2 dimension from the entire array to neighboring candidate beams according to beam offsets, which are used to indicate the set of possible beam candidates with respect to the first beam.

[0087] In some embodiments, the first offset and the second offset correspond to beam offsets for a rank equal to 2. In an example, the set of beam offsets k , k2can follow the 3GPP legacy Release 15 Table of beam offsets for rank = 2.

[0088] In other embodiments, the first offset and the second offset correspond to beam offsets for a rank equal to 3 or 4 when a number of channel CSI-RS ports associated with the CSI report configuration. In an example, the set of beam offsets kltk2can follow the 3GPP legacy Release 15 Table of beam offsets for ranks = 3 or 4 when the number of CSI-RS ports is less or equal to 16 (Pcsi- R

[0089] It is noted that in 3GPP Release 19, it was agreed to reuse the last column of Table 4 discussed herein for the new values of NltN2when PCSI-RS > 32.

[0090] For ease of discussion, Figures 8-15 show non- limiting examples of a set of beam candidates for a scenario in which a PMI is composed using two beams. However, the disclosure is not so limited and includes other scenarios that include any number of beams. For example, the case agreed in 3GPP Release 19, for ranks greater than 4.

[0091] Figure 8 shows an example where a first beam 800 is selected and the full set of second DFT beam candidates 802 according to Scheme A for ranks greater than 4 are shown. However, by implementing an improved version of Scheme A and applying the restriction based on the 3GPP legacy offset values from Release 15 or Release 19 for ranks 3-4, the UE needs to search only the beams 804, thus, significantly reducing the search space. In other words, the implementation shown in the example in Figure 8, is an improved implementation according to a reduced set of extended beams based on 3GPP legacy Release 15 codebook design or Release 19 for ranks less or equal to 4.

[0092] It is noted that to fully implement Scheme A for ranks greater than 4, in addition to computing the second set of beam candidates 802, a UE would further have to compute potential beam candidate combinations for the third and fourth beams as well (when the rank is up to 7 or 8), and would be limited to selecting beams that are orthogonal in at least one of the dimensions to all previously computed beam sets.

[0093] The following examples include an improved implementation according to a second scheme, such as Scheme B for example.

[0094] In some embodiments, the subset of candidate beam combinations include beams that are orthogonal in both the first dimension and the second dimension with respect to beams in a second scheme for the codebook. In an example, the selection of second, third, and fourth DFT beams are constrained to just the candidate beam combinations that are orthogonal in both A^and N2dimensions with respect to the other selected beams (e.g., as in Scheme B).

[0095] Figure 9 shows an example where a first beam 800 is selected and the full set of second DFT beam candidates 802 according to Scheme A for ranks greater than 4 are shown. By implementing an improved version of Scheme A and applying the restriction based on Scheme B, the UE needs to search only the beams 804, thus, significantly reducing the beam candidate combinations and the PMI search space. In Figure 9, the DFT beam candidates 804 are orthogonal in in both N and N2dimensions. Thus, in some embodiments, identifying (operation 1606 in Figure 16) includes searching the candidate beam combinations that are orthogonal in both the first dimension and the second dimension with respect to beams in a second scheme for the codebook.

[0096] In other embodiments, the second scheme for the codebook includes at least one of (i) for a rank that is less than or equal to 4, a candidate precoder including less than or equal to 4 beams that are orthogonal to each other in both the first dimension and the second dimension; and (ii) for a rank greater than 4, a candidate precoder including between a single beam shared among two layers to 4 beams that are orthogonal to each other in both the first dimension and the second dimension.

[0097] Yet other examples include an improved implementation according to reduced set of extended beams based on, e.g., a 3GPP Release 15 codebook design.

[0098] In some embodiments, the subset of candidate beam combinations includes up to 4 beams from a plurality of beam groups that have a first offset and a second offset with respect to a previously selected beam. For example, the selection of second, third, and fourth DFT beams are constrained to just the neighboring beams following the legacy (k1(k2) offsets from 3GPP Release 15. As such, instead of computing all beam candidate combinations of 2, 3 and 4 beams that are orthogonal in either of the dimensions, up to 4 beams are selected from neighboring beam groups.

[0099] Figure 10 shows an example where a first beam 800 is selected and the full set of second DFT beam candidates 802 according to Scheme A for ranks greater than 4 are shown. However, by implementing an improved version of Scheme A and applying the restriction based on the legacy offset values from 3GPP Release 15, the UE needs to search only the beams 804, thus, significantly reducing the search space.

[0100] In some embodiments, identifying (operation 1606 in Figure 16) includes searching the up to 4 beams from the plurality of beams that have the first offset and the second offset with respect to the previously selected beam and that are orthogonal in either a first dimension and a second dimension.

[0101] Still other examples include an improved implementation by limiting beam search according to a certain metric.

[0102] For example, the selection of second, third and fourth DFT beams are constrained via another method, in which first the UE measures a certain metric, such as highest average / sum received signal power (RSRP) across beam groups in order to filter potential beam groups to be searched. After performing this first down selection, the UE then picks the next beams from these candidates beam groups.

[0103] In another example, the UE selects beams from these groups by limiting the selection of beams to be of beams that are orthogonal in both N and N2dimensions (e.g., a subset of Scheme B).

[0104] In a further example, the UE selects a simplified set of beam candidates based on a metric from these groups by limiting the selection of beams to be of beams 804 that are orthogonal in N and N2dimensions (e.g., a subset of Scheme A for ranks greater than 4), as shown in Figure 11.

[0105] Figure 12 shows an example of a simplified set of DFT beam candidates 804 based on a certain metric and that are orthogonal in either N or N2dimensions or in both N and N2dimensions.

[0106] In some embodiments, identifying (operation 1606 in Figure 16) includes searching the subset of candidate beam combinations that satisfy a metric to identify at least one candidate beam that is orthogonal in either the first dimension or the second dimension, and transmitting (operation 1608 in Figure 16) includes transmitting the at least one candidate beam from the second process for the codebook.

[0107] A sequential beam search may be included. For example, a UE can alternatively perform a sequential implementation in order to further reduce complexity.

[0108] In some embodiments, identifying (operation 1606 in Figure 16) includes: performing a sequential beam search to select a strongest beam among the subset of candidate beam combinations as a first beam, wherein a remainder of the subset of candidate beam combinations comprise a resulting set of beam candidate combinations for a next beam, and selecting a strongest beam from the resulting set of beams candidate combinations as the next beam.

[0109] In an example shown in Figures 13 - 15, the first selected beam 1000 is the strongest beam among all beam candidates. In this example, when the UE has already selected M of L of beams 1004, 1008 required to compose the PMI (1 < M < L), the UE then selects the strongest beam 1012 from the resulting set of beam candidates 1010 as the next beam (M + 1thbeam). The UE performs this procedure in a sequential manner. Therefore, in this example, the search is reduced to a single combination of beams.

[0110] Operations of a UE can be performed by the UE 1800 of Figure 18. Operations of the UE (implemented using the structure of Figure 18) have been discussed with reference to the flow chart of Figure 16 according to some embodiments of the present disclosure. Operation 1604 of Figure 16 may be optional with respect to some embodiments of UEs and related methods. Modules may be stored in memory 1810 of Figure 18, for example, and these modules may provide instructions so that when the instructions of a module are executed by respective UE processing circuitry 1802 (also referred to herein as a processor(s)), UE 1800 performs respective operations of the flow chart of Figure 16.

[0111] Figure 17 shows an example of a communication system 1700 in accordance with some embodiments.

[0112] In the example, the communication system 1700 includes a telecommunication network 1702 that includes an access network 1704, such as a radio access network (RAN), and a core network 1706, which includes one or more core network nodes 1708. The access network 1704 includes one or more access network nodes, such as network nodes 1710a and 1710b (one or more of which may be generally referred to as network nodes 1710), or any other similar 3GPP access nodes or non-3GPP access points. 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 1702 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 1702 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 1702, including one or more network nodes 1710 and / or core network nodes 1708.

[0113] 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 Al, Fl, Wl, El, 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 ina 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 0-2 interface defined by the 0-RAN Alliance or comparable technologies. The network nodes 1710 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 1712a, 1712b, 1712c, and 1712d (one or more of which may be generally referred to as UEs 1712) to the core network 1706 over one or more wireless connections.

[0114] 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 1700 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 1700 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0115] The UEs 1712 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 1710 and other communication devices. Similarly, the network nodes 1710 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 1712 and / or with other network nodes or equipment in the telecommunication network 1702 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 1702.

[0116] In the depicted example, the core network 1706 connects the network nodes 1710 to one or more host computing systems, such as host 1716. 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 1706 includes one more core network nodes (e.g., core network node 1708) 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 1708. 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), SessionManagement 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).

[0117] The host 1716 may be under the ownership or control of a service provider other than an operator or provider of the access network 1704 and / or the telecommunication network 1702. The host 1716 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.

[0118] As a whole, the communication system 1700 of Figure 17 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system 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 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 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.

[0119] In some examples, the telecommunication network 1702 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1702 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1702. For example, the telecommunications network 1702 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 loT services to yet further UEs.

[0120] In some examples, the UEs 1712 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 1704 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1704. Additionally, a UE may be configured for operating in single- or multi-RAT or multi-standard mode. For example, a UE mayoperate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi -radio dual connectivity (MR-DC), such as E-UTRAN (Evolved- UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

[0121] In the example, the hub 1714 communicates with the access network 1704 to facilitate indirect communication between one or more UEs (e.g., UE 1712c and / or 1712d) and network nodes (e.g., network node 1710b). In some examples, the hub 1714 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 1714 may be a broadband router enabling access to the core network 1706 for the UEs. As another example, the hub 1714 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 1710, or by executable code, script, process, or other instructions in the hub 1714. As another example, the hub 1714 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 1714 may be a content source. For example, for a UE that is a VR device, display, loudspeaker, or other media delivery device, the hub 1714 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1714 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 1714 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy loT devices.

[0122] The hub 1714 may have a constant / persistent or intermittent connection to the network node 1710b. The hub 1714 may also allow for a different communication scheme and / or schedule between the hub 1714 and UEs (e.g., UE 1712c and / or 1712d), and between the hub 1714 and the core network 1706. In other examples, the hub 1714 is connected to the core network 1706 and / or one or more UEs via a wired connection. Moreover, the hub 1714 may be configured to connect to an M2M service provider over the access network 1704 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 1710 while still connected via the hub 1714 via a wired or wireless connection. In some embodiments, the hub 1714 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 1710b. In other embodiments, the hub 1714 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 1710b, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0123] Figure 18 shows a UE 1800 in accordance with some embodiments. The UE 1800 presents additional details of some embodiments of the UE 1712 of Figure 17. 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 IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage / playback device, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), an Augmented Reality (AR) or Virtual Reality (VR) device, wireless customer-premise equipment (CPE), vehicle, vehicle-mounted or vehicle embedded / integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and / or an enhanced MTC (eMTC) UE.

[0124] A UE may support device-to-device (D2D) communication, for example by implementing a 3 GPP 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).

[0125] The UE 1800 includes processing circuitry 1802 that is operatively coupled via a bus 1804 to an input / output interface 1806, a power source 1808, a memory 1810, a communication interface 1812, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 18. 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.

[0126] The processing circuitry 1802 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 1810. The processing circuitry 1802 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 1802 may include multiple central processing units (CPUs).

[0127] In the example, the input / output interface 1806 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 1800. 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.

[0128] In some embodiments, the power source 1808 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 1808 may further include power circuitry for delivering power from the power source 1808 itself, and / or an external power source, to the various parts of the UE 1800 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1808. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1808 to make the power suitable for the respective components of the UE 1800 to which power is supplied.

[0129] The memory 1810 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 1810 includes one or more application programs 1814, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1816. The memory 1810 may store, for use by the UE 1800, any of a variety of various operating systems or combinations of operating systems.

[0130] The memory 1810 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 random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and / or 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 ‘SIM card.’ The memory 1810 may allow the UE 1800 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 1810, which may be or comprise a device-readable storage medium.

[0131] The processing circuitry 1802 may be configured to communicate with an access network or other network using the communication interface 1812. The communication interface 1812 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1822. The communication interface 1812 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 network node in an access network). Each transceiver may include a transmitter 1818 and / or a receiver 1820 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 1818 and receiver 1820 may be coupled to one or more antennas (e.g., antenna 1822) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0132] In the illustrated embodiment, communication functions of the communication interface 1812 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, 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 in according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission controlprotocol / intemet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

[0133] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 1812, 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 15 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).

[0134] 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.

[0135] A UE, when in the form of an Internet of Things (loT) 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 loT device are a device which is or which is embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, 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 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 loT device comprises circuitry and / or software in dependence of the intended application of the loT device in addition to other components as described in relation to the UE 1800 shown in Figure 18.

[0136] As yet another specific example, in an loT 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 3 GPP context be referred to as an MTC device. As oneparticular 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 and an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0137] 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.

[0138] Figure 19 shows a network node 1900 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, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)), O-RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O-CU).

[0139] 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 remote radio units 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).

[0140] 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 base station 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).

[0141] The network node 1900 includes a processing circuitry 1902, a memory 1904, a communication interface 1906, and a power source 1908. The network node 1900 may be composed of multiple physically separate components (e.g., a NodeB component and a 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 1900 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 1900 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 1904 for different RATs) and some components may be reused (e.g., a same antenna 1910 may be shared by different RATs). The network node 1900 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1900, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, 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 network node 1900.

[0142] The processing circuitry 1902 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application- specific integrated circuit, field programmable gate array, 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 1900 components, such as the memory 1904, to provide network node 1900 functionality.

[0143] In some embodiments, the processing circuitry 1902 includes a system on a chip (SOC). In some embodiments, the processing circuitry 1902 includes one or more of radio frequency (RF) transceiver circuitry 1912 and baseband processing circuitry 1914. In some embodiments, the radio frequency (RF) transceiver circuitry 1912 and the baseband processing circuitry 1914 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 RF transceiver circuitry 1912 and baseband processing circuitry 1914 may be on the same chip or set of chips, boards, or units.

[0144] The memory 1904 may comprise any form of volatile or non-volatile computer-readable memory including, without limitation, persistent storage, solid-state memory, remotelymounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (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 1902. The memory 1904 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 1902 and utilized by the network node 1900. The memory 1904 may be used to store any calculations made by the processing circuitry 1902 and / or any data received via the communication interface 1906. In some embodiments, the processing circuitry 1902 and memory 1904 is integrated.

[0145] The communication interface 1906 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 1906 comprises port(s) / terminal(s) 1916 to send and receive data, for example to and from a network over a wired connection. The communication interface 1906 also includes radio front-end circuitry 1918 that may be coupled to, or in certain embodiments a part of, the antenna 1910. Radio front-end circuitry 1918 comprises filters 1920 and amplifiers 1922. The radio front-end circuitry 1918 may be connected to an antenna 1910 and processing circuitry 1902. The radio front-end circuitry may be configured to condition signals communicated between antenna 1910 and processing circuitry 1902. The radio front-end circuitry 1918 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio frontend circuitry 1918 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 1920 and / or amplifiers 1922. The radio signal may then be transmitted via the antenna 1910. Similarly, when receiving data, the antenna 1910 may collect radio signals which are then converted into digital data by the radio front-end circuitry 1918. The digital data may be passed to the processing circuitry 1902. In other embodiments, the communication interface may comprise different components and / or different combinations of components.

[0146] In certain alternative embodiments, the network node 1900 does not include separate radio front-end circuitry 1918, instead, the processing circuitry 1902 includes radio front-end circuitry and is connected to the antenna 1910. Similarly, in some embodiments, all or some of the RF transceiver circuitry 1912 is part of the communication interface 1906. In still other embodiments, the communication interface 1906 includes one or more ports or terminals 1916, the radio front-end circuitry 1918, and the RF transceiver circuitry 1912, as part of a radio unit(not shown), and the communication interface 1906 communicates with the baseband processing circuitry 1914, which is part of a digital unit (not shown).

[0147] The antenna 1910 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 1910 may be coupled to the radio front-end circuitry 1918 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 1910 is separate from the network node 1900 and connectable to the network node 1900 through an interface or port.

[0148] The antenna 1910, communication interface 1906, and / or the processing circuitry 1902 may be configured to perform any receiving operations and / or certain obtaining operations described herein as being performed by the network node. Any information, data and / or signals may be received from a UE, another network node and / or any other network equipment. Similarly, the antenna 1910, the communication interface 1906, and / or the processing circuitry 1902 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and / or signals may be transmitted to a UE, another network node and / or any other network equipment.

[0149] The power source 1908 provides power to the various components of network node 1900 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 1908 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 1900 with power for performing the functionality described herein. For example, the network node 1900 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 1908. As a further example, the power source 1908 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.

[0150] Embodiments of the network node 1900 may include additional components beyond those shown in Figure 19 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 1900 may include user interface equipment to allow input of information into the network node 1900 and to allow output of information from the network node 1900. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 1900. In some embodiments providing a core network node, such as core network node 1708 of Figure 17, somecomponents, such as the radio front-end circuitry 1918 and the RF transceiver circuitry 1912 may be omitted.

[0151] Figure 20 is a block diagram illustrating a virtualization environment 2000 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 2000 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 2000 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. Virtualization may facilitate distributed implementations of a network node, UE, core network node, or host.

[0152] Applications 2002 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment 2000 to implement some of the features, functions, and / or benefits of some of the embodiments disclosed herein.

[0153] Hardware 2004 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 2006 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 2008a and 2008b (one or more of which may be generally referred to as VMs 2008), and / or perform any of the functions, features and / or benefits described in relation with some embodiments described herein. The virtualization layer 2006 may present a virtual operating platform that appears like networking hardware to the VMs 2008.

[0154] The VMs 2008 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 2006. Different embodiments of the instance of a virtual appliance 2002 may be implemented on one ormore of VMs 2008, 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.

[0155] In the context of NFV, a VM 2008 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 2008, and that part of hardware 2004 that executes that VM, be it hardware dedicated to that VM and / or hardware shared by that VM with others of the VMs, 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 2008 on top of the hardware 2004 and corresponds to the application 2002.

[0156] Hardware 2004 may be implemented in a standalone network node with generic or specific components. Hardware 2004 may implement some functions via virtualization. Alternatively, hardware 2004 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 2010, which, among others, oversees lifecycle management of applications 2002. In some embodiments, hardware 2004 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 radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system 2012 which may alternatively be used for communication between hardware nodes and radio units.

[0157] Although computing devices described herein (e.g., UEs, network nodes) 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 the obtained information or converted information, and as a result of said processing making a determination. Moreover, whilecomponents 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.

[0158] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on 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 hard-wired 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.

[0159] In certain embodiments, a UE 1712A, 1712B, 1800 is provided. The UE 1800 includes processing circuitry 1802; and memory 1810 coupled with the processing circuitry. The memory includes instructions that when executed by the processing circuitry causes the UE to perform operations. The operations include to perform some or all of the functionality described herein.

[0160] In certain embodiments, a non-transitory computer readable medium 1810 is provided, including program code to be executed by processing circuitry 1802 of a UE 1712A, 1712B, 1800. Execution of the program code causes the program code to perform operations. The operations include to perform some or all of the functionality described herein.

[0161] Further definitions and embodiments are discussed below.

[0162] In the above-description of certain embodiments of the present disclosure, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which concepts of the present disclosure belong. It will be further understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0163] When an element is referred to as being “connected”, “coupled”, “responsive”, or variants thereof to another element, it can be directly connected, coupled, or responsive to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected”, “directly coupled”, “directly responsive”, or variants thereof to another element, there are no intervening elements present. Like numbers refer to like elements throughout. Furthermore, “coupled”, “connected”, “responsive”, or variants thereof as used herein may include wirelessly coupled, connected, or responsive. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Well-known functions or constructions may not be described in detail for brevity and / or clarity. The term “and / or” (abbreviated “ / ”) includes any and all combinations of one or more of the associated listed items.

[0164] It will be understood that although the terms first, second, third, etc. may be used herein to describe various elements / operations, these elements / operations should not be limited by these terms. These terms are only used to distinguish one element / operation from another element / operation. Thus a first element / operation in some embodiments could be termed a second element / operation in other embodiments without departing from the teachings of concepts of the present disclosure. The same reference numerals or the same reference designators denote the same or similar elements throughout the specification.

[0165] As used herein, the terms “comprise”, “comprising”, “comprises”, “include”, “including”, “includes”, “have”, “has”, “having”, or variants thereof are open-ended, and include one or more stated features, integers, elements, steps, components, or functions but does not preclude the presence or addition of one or more other features, integers, elements, steps, components, functions, or groups thereof. Furthermore, as used herein, the common abbreviation “e.g.”, which derives from the Latin phrase “exempli gratia,” may be used to introduce or specify a general example or examples of a previously mentioned item, and is not intended to be limiting of such item. The common abbreviation “i.e.”, which derives from the Latin phrase “id est,” may be used to specify a particular item from a more general recitation.

[0166] Example embodiments are described herein with reference to block diagrams and / or flowchart illustrations of computer-implemented methods, apparatus (systems and / or devices) and / or computer program products. It is understood that a block of the block diagrams and / or flowchart illustrations, and combinations of blocks in the block diagrams and / or flowchartillustrations, can be implemented by computer program instructions that are performed by one or more computer circuits. These computer program instructions may be provided to a processor circuit of a general purpose computer circuit, special purpose computer circuit, and / or other programmable data processing circuit to produce a machine, such that the instructions, which execute via the processor of the computer and / or other programmable data processing apparatus, transform and control transistors, values stored in memory locations, and other hardware components within such circuitry to implement the functions / acts specified in the block diagrams and / or flowchart block or blocks, and thereby create means (functionality) and / or structure for implementing the functions / acts specified in the block diagrams and / or flowchart block(s).

[0167] These computer program instructions may also be stored in a tangible computer-readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instructions which implement the functions / acts specified in the block diagrams and / or flowchart block or blocks. Accordingly, embodiments of the present disclosure may be embodied in hardware and / or in software (including firmware, resident software, micro-code, etc.) that runs on a processor such as a digital signal processor, which may collectively be referred to as “circuitry,” “a module” or variants thereof.

[0168] It should also be noted that in some alternate implementations, the functions / acts noted in the blocks may occur out of the order noted in the flowcharts. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality / acts involved. Moreover, the functionality of a given block of the flowcharts and / or block diagrams may be separated into multiple blocks and / or the functionality of two or more blocks of the flowcharts and / or block diagrams may be at least partially integrated. Finally, other blocks may be added / inserted between the blocks that are illustrated, and / or blocks / operations may be omitted without departing from the scope of the present disclosure. Moreover, although some of the diagrams include arrows on communication paths to show a primary direction of communication, it is to be understood that communication may occur in the opposite direction to the depicted arrows.

[0169] Many variations and modifications can be made to the embodiments without substantially departing from the principles of the present disclosure. All such variations and modifications are intended to be included herein within the scope of present disclosure. Accordingly, the above disclosed subject matter is to be considered illustrative, and not restrictive, and the examples of embodiments are intended to cover all such modifications, enhancements, and other embodiments, which fall within the spirit and scope of the present disclosure. Thus, to themaximum extent allowed by law, the scope of the present disclosure is to be determined by the broadest permissible interpretation of the present disclosure including the examples of embodiments and their equivalents, and shall not be restricted or limited by the foregoing detailed description.

Claims

Claims:

1. A method performed by a user equipment, UE, for reporting channel state information, CSI, the method comprising:transmitting (1600) an indication that the UE supports a first scheme for a codebook in which a candidate precoder comprises a set of beams that are orthogonal to each other in at least one of a first dimension and a second dimension;receiving (1602) a CSI report configuration for the codebook;identifying (1606) a precoding matrix indicator, PMI, from a subset of candidate beam combinations in the codebook allowed by the first scheme; andtransmitting (1608) the PMI based on the CSI report configuration.

2. The method of Claim 1, wherein the identifying (1606) comprises searching the subset of candidate beam combinations according to a first oversampling factor in the first dimension and to a second oversampling factor in the second dimension.

3. The method of any one of Claims 1 to 2, wherein the subset of candidate beams is according to supported candidate beam combinations of the first scheme for the codebook for a rank of less than or equal to 4 using a first offset and a second offset when the UE is configured for a rank larger than 4.

4. The method of Claim 3, wherein the first offset and the second offset correspond to beam offsets for a rank equal to 2.

5. The method of Claim 3, wherein the first offset and the second offset correspond to beam offsets for a rank equal to 3 or 4 when a number of channel CSI-reference signal (RS) ports associated with the CSI report configuration.

6. The method of any one of Claims 3 to 5, wherein the identifying (1606) comprises searching the subset of candidate beam combinations from the codebook for a rank of less than or equal to 4, wherein respective candidate beams in the subset have a first offset and a second offset with respect to a previously selected beam.

7. The method of any one of Claims 1 to 2, wherein the subset of candidate beam combinations comprise supported candidate beam combinations of a second scheme for the codebook for ranks 5 to 8, using a first offset and a second offset.

8. The method of any one of Claims 1 to 2, wherein the subset of candidate beam combinations comprise supported candidate beam combinations of a second scheme for the codebook.

9. The method of any one of Claims 1 to 2, wherein the subset of candidate beam combinations comprise beams that are orthogonal in both the first dimension and the second dimension with respect to beams in a second scheme for the codebook.

10. The method of Claim 9, wherein the identifying (1606) comprises searching the candidate beam combinations that are orthogonal in both the first dimension and the second dimension with respect to beams in the second scheme for the codebook.

11. The method of any one of Claims 9 to 10, wherein the second scheme for the codebook comprises at least one of (i) for a rank that is less than or equal to 4, a candidate precoder comprising less than or equal to 4 beams that are orthogonal to each other in both the first dimension and the second dimension; and (ii) for a rank greater than 4, a candidate precoder comprising between a single beam shared among two layers to 4 beams that are orthogonal to each other in both the first dimension and the second dimension.

12. The method of any one of Claims 1 to 2, wherein the subset of candidate beam combinations comprises up to 4 beams from a plurality of beam groups that have a first offset and a second offset with respect to a previously selected beam.

13. The method of Claim 12, wherein the identifying (1606) comprises searching the up to 4 beams from the plurality of beams that have the first offset and the second offset with respect to the previously selected beam and that are orthogonal in either a first dimension and a second dimension.

14. The method of any one of Claims 1 to 2, wherein the subset of candidate beam combinations comprise a subset of a plurality of beam groups, the method further comprising:filtering (1604) the plurality of beam groups based on a metric to identify the subset of candidate beam combinations that satisfy the metric, andwherein the identifying (1606) comprises searching the subset of candidate beam combinations that satisfy the metric to identify at least one candidate beam for the PMI.

15. The method of Claim 14, wherein the identifying (1606) comprises searching the subset of candidate beam combinations that satisfy the metric to identify at least one candidate beam that is orthogonal in both the first dimension and the second dimension, and wherein the transmitting (1608) comprises transmitting the at least one candidate beam from a second scheme for the codebook.

16. The method of Claim 14, wherein the identifying (1606) comprises searching the subset of candidate beam combinations that satisfy the metric to identify at least one candidate beam that is orthogonal in either the first dimension or the second dimension, and wherein the transmitting (1608) comprises transmitting the at least one candidate beam from the second process for the codebook .

17. The method of any one of Claims 1 to 2, wherein the identifying (1606) comprises: performing a sequential beam search to select a strongest beam among the subset of candidate beam combinations as a first beam, wherein a remainder of the subset of candidate beam combinations comprise a resulting set of beam candidate combinations for a next beam, andselecting a strongest beam from the resulting set of beams candidate combinations as the next beam.

18. The method of Claim 17, further comprising:repeating the identifying (1606) for a subsequent next beam.

19. A user equipment, UE, (1712A, 1712B, 1800) comprising:processing circuitry (1802);memory (1810) coupled with the processing circuitry, wherein the memory includes instructions that when executed by the processing circuitry causes the UE to perform operations comprising:transmit an indication that the UE supports a first scheme for a codebook in which a candidate precoder comprises a set of beams that are orthogonal to each other in at least one of a first dimension and a second dimension;receive a CSI report configuration for the codebook;identify a precoding matrix indicator, PMI, from a subset of candidate beam combinations in the codebook allowed by the first scheme; andtransmit the PMI based on the CSI report configuration.

20. The UE of Claim 19, wherein the memory includes instructions that when executed by the processing circuitry causes the UE to perform operations that further comprise any one of the operations of Claims 2 to 18.

21. A non-transitory computer readable medium (1810) including program code to be executed by processing circuitry (1802) of a user equipment, UE, (1712A, 1712B, 1800), whereby execution of the program code causes the program code to perform operations comprising:transmit an indication that the UE supports a first scheme for a codebook in which a candidate precoder comprises a set of beams that are orthogonal to each other in at least one of a first dimension and a second dimension;receive a CSI report configuration for the codebook;identify a precoding matrix indicator, PMI. From a subset of candidate beam combinations in the codebook allowed by the first scheme; andtransmit the PMI based on the CSI report configuration.

22. The non-transitory computer readable medium of Claim 21, the operations further comprising any of the operations of Claims 2-18.

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