CSI reporting for type II precoders

Abstract

According to some embodiments, a method performed by a wireless device for channel state information (CSI) reporting. The method comprises: measuring a plurality of instances of a CSI reference signal (CSI-RS) over a span of time instances; estimating linear combination coefficients for combining a spatial domain (SD) basis, a frequency domain (FD) basis, and a Doppler domain (DD) basis from the measurements of the plurality of CSI-RS instances; and predicting the precoder using the linear combination coefficients, the SD basis, the FD basis, and the DD basis.

Description

Technical Field

[0001] Embodiments of the present disclosure are directed to wireless communications, and more particularly, to channel state information (CSI) reporting for a Type II precoder. Background Art

[0002] Generally, all terms used herein should be interpreted according to their ordinary meanings in the relevant technical field, unless different meanings are clearly given and / or different meanings are implied from the context of their use. Unless otherwise clearly stated, all references to elements, devices, components, members, operations, etc. should be publicly interpreted as referring to at least one instance of elements, devices, components, members, operations, etc. The operation of any method disclosed herein does not have to be performed in the exact order disclosed, unless an operation is clearly described after or before another operation and / or an operation is implied to be after or before another operation. Any feature of any embodiment disclosed herein can be applied to any other embodiment (wherever appropriate). Similarly, any advantage of any embodiment can be applied to any other embodiment, and vice versa. Other goals, features and advantages of the attached embodiments will be apparent from the following description.

[0003] Multiple antenna technology can significantly increase the data rate and reliability of wireless communication systems. Performance is particularly improved if both the transmitter and receiver are equipped with multiple antennas, resulting in a multiple-input multiple-output (MIMO) communication channel. Such systems and / or related technologies are generally referred to as MIMO.

[0004] The 3rd Generation Partnership Project (3GPP) New Radio (NR) standard is currently evolving with enhanced MIMO support. A core component in NR is support for MIMO antenna deployment and MIMO-related technologies such as spatial multiplexing. The spatial multiplexing mode is designed for high data rates under favorable channel conditions. Figure 1 An example of spatial multiplexing operation is shown.

[0005] Figure 1 is a block diagram showing the transmission structure of the precoded spatial multiplexing mode in New Radio (NR). As shown in the figure, the information carrying symbol vector s is connected to N T xr is multiplied by the precoder matrix W, which is used to distribute the transmission energy over N T (corresponding to N TThe precoder matrix is ​​typically selected from a codebook of possible precoder matrices and is typically indicated by a precoder matrix indicator (PMI) that specifies a unique precoder matrix in the codebook for a given number of symbol streams. Each of the r symbols in s corresponds to a layer, and r is called the transmission rank. In this way, spatial multiplexing is achieved because multiple symbols can be transmitted simultaneously via the same time / frequency resource element (TFRE). The number of symbols r is typically adapted based on the current channel properties.

[0006] NR uses Orthogonal Frequency Division Multiplexing (OFDM) in the downlink (Discrete Fourier Transform (DFT) precoded OFDM is used in the uplink for rank 1 transmission), so the received N for a certain TFRE on subcarrier n (or alternatively data TFRE number n) is R x1 vector y n Modeled by: y n =H n W n +e n Among them, e n is the noise / interference vector obtained as a realization of a random process. The precoder W can be a wideband precoder, which is constant in frequency, or frequency selective.

[0007] The precoder matrix W is usually chosen to be consistent with N R xN T MIMO channel matrix H n This is also often referred to as closed-loop precoding and essentially focuses the transmission energy into a subspace that is strong in the sense that most of the transmission energy is delivered to the user equipment (UE).

[0008] In closed-loop precoding for NR downlink, the UE sends a suggestion to the gNB for a suitable precoder to use based on channel measurements in the downlink. The gNB configures the UE to provide feedback according to CSI-ReportConfig, and may send a Channel State Information Reference Signal (CSI-RS), and configures the UE to use measurements of the CSI-RS to feedback the recommended precoding matrix that the UE selected from the codebook. A single precoder that should cover a large bandwidth (wideband precoding) may be fed back. It may also be beneficial to match the frequency variations of the channel and instead feed back frequency selective precoding reports (e.g., several precoders, one per subband).

[0009] This is an example of a more general case of Channel State Information (CSI) feedback, which also covers feeding back other information besides the recommended precoder to assist the gNodeB in subsequent transmissions to the UE. Such other information may include a Channel Quality Indicator (CQI) as well as a Transmission Rank Indicator (RI). In NR, CSI feedback can be either wideband, where one CSI is reported for the entire channel bandwidth, or frequency selective, where one CSI is reported for each subband, which is defined as the number of consecutive resource blocks, depending on the size of the bandwidth part (BWP), ranging between 4-32 physical resource blocks (PRBs).

[0010] Given the CSI feedback from the UE, the gNB determines the transmission parameters it wishes to use to send to the UE, including the precoding matrix, transmission rank, and modulation and coding scheme (MCS). These transmission parameters may be different from those proposed by the UE. The transmission rank, and therefore the number of spatial multiplexing layers, is reflected in the number of columns of the precoder W. For efficient performance, it is very important to choose a transmission rank that matches the channel properties.

[0011] With multi-user MIMO (MU-MIMO), two or more users in the same cell are co-scheduled on the same time-frequency resources. That is, two or more independent data streams are sent to different UEs at the same time, and the corresponding streams can usually be separated using the spatial domain. By sending multiple streams simultaneously, the capacity of the system can be increased. However, this comes at the expense of a reduced signal-to-interference-plus-noise ratio (SINR) for each stream, since power must be shared between streams and the streams will interfere with each other.

[0012] For CSI measurement and feedback, CSI-RS is defined. CSI-RS is sent on each antenna port and is used by the UE to measure the downlink channel between each transmit antenna port and each of its receive antenna ports. The transmit antenna port is also called a CSI-RS port.

[0013] The number of antenna ports supported in NR is {1, 2, 4, 8, 12, 16, 24, 32}. By measuring the received CSI-RS, the UE can estimate the channel that the CSI-RS is traversing, including the radio propagation channel and antenna gain. The CSI-RS used for the above purpose is also called non-zero power (NZP) CSI-RS.

[0014] The CSI-RS may be configured to be transmitted in certain REs in a slot and in certain slots. Figure 2 An example is shown in FIG.

[0015] Figure 2is a time-frequency diagram showing an example of CSI-RS resource element (RE) allocation for a 12-port CSI-RS in NR. The example shown includes REs for 12 antenna ports, where 1 RE per RB per port is shown.

[0016] In addition, interference measurement resources (IMR) are defined in NR for UE to measure interference. IMR resources contain 4 REs, which can be 4 adjacent REs in frequency in the same OFDM symbol, or 2×2 adjacent REs in both time and frequency in a time slot. By measuring the channel based on NZP CSI-RS and measuring interference based on IMR, the UE can estimate the effective channel and noise plus interference to determine CSI, i.e., rank, precoding matrix, and channel quality.

[0017] In addition, a UE in NR may be configured to measure interference based on one or more NZP CSI-RS resources.

[0018] 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, the UE feeds back a CSI report.

[0019] Each CSI reporting setting contains at least the following information: (a) CSI-RS resource set for channel measurement; (b) IMR resource set for interference measurement; (c) optionally, CSI-RS resource set for interference measurement; (d) time domain behavior, i.e. periodic, semi-persistent or aperiodic reporting; (e) frequency granularity, i.e. wideband or subband; (f) CSI parameters to be reported, such as RI, PMI, CQI and CSI-RS resource indicator (CRI) in the case of multiple CSI-RS resources in a resource set; (g) codebook type, i.e. type I or II, and codebook subset restrictions; (h) measurement restrictions; and (i) subband size. Indicates one of the two possible subband sizes. The value range depends on the bandwidth of the BWP. One channel quality indicator (CQI) / precoding matrix indicator (PMI) is fed back per subband (if configured for subband reporting).

[0020] When a CSI-RS resource set in the CSI reporting setting contains multiple CSI-RS resources, the UE selects one of the CSI-RS resources, and the UE also reports a CSI-RS resource indicator (CRI) to indicate to the gNB the selected CSI-RS resource in the resource set, as well as the RI, PMI, and CQI associated with the selected CSI-RS resource.

[0021] For aperiodic CSI reporting in NR, more than one CSI reporting setting can be configured and triggered simultaneously, each with a different CSI-RS resource set for channel measurement and / or resource set for interference measurement. In this case, multiple CSI reports are aggregated and sent from the UE to the gNB in ​​a single physical uplink shared channel (PUSCH).

[0022] The UE typically uses a Type-I codebook (CB) to report CSI for single-user MIMO (SU-MIMO) scheduling in N, while a Type-II CB is typically used for more accurate CSI feedback for multi-user MIMO (MU-MIMO) scheduling.

[0023] For Type I and Type II CB, for each rank, the precoding matrix W is defined as W = W1W2, where is a 2Nx2L matrix and contains the L selected DFT beams {d i ,i=1,…,L}, where d i is an Nx1 DFT vector, N is the number of CSI-RS ports per polarization; and W2 is a 2L×v matrix and contains the co-phasing coefficients between the selected beams and also between antenna ports with two different polarizations, where v is the number of layers or rank. W1 is the same for the entire CSI bandwidth, while W2 can be for the entire bandwidth or for each subband.

[0024] For Type I CB, the precoding vector for each MIMO layer is associated with a single DFT beam, whereas for Type II CB, the precoding vector for each layer is a linear combination of multiple DFT beams.

[0025] In NR Rel-16, Type II CB is enhanced by applying a frequency domain (FD) DFT basis across all subbands to reduce CSI feedback overhead and / or improve CSI accuracy. Instead of reporting W2 for each subband, a linear combination of DFT basis vectors is used to jointly represent W2 across the entire CSI bandwidth. For each layer, the precoding matrix W across all subbands is In the form of f =[f1,…,f M ] is a matrix containing M selected DFT basis vectors {f1,…,f M}, is a 2L x M matrix containing coefficients for each selected DFT beam and each selected FD basis vector.

[0026] The relative motion between the transmitter and the receiver causes Doppler spread. Assume that the bandwidth of the transmitted signal is proportional to the carrier frequency f cIf the ratio is very small, the signal component at an angle θ to the direction of motion of the receiver will cause a Doppler shift Where v is the relative velocity of the receiver and c is the speed of light in free space. When θ = 0 and π, the maximum possible Doppler shift f is obtained. D,max With multipath propagation, signal components arriving at the receiver from different directions experience different Doppler shifts, and the total received signal exhibits a frequency spread around the carrier frequency. The width of the spread around the carrier frequency is called the Doppler spread. The precise definition of Doppler spread varies across the literature, and f D,max Often used as an approximation of the Doppler spread. The Doppler properties of the received signal are often captured using the Doppler power spectrum, which is correlated with the temporal autocorrelation function of the time-varying channel via a Fourier transform. Thus, the availability of the Doppler power spectrum or its properties allows modeling of the temporal variations of the channel.

[0027] There are certain challenges. For example, downlink MU-MIMO precoding performance degrades when one or more co-scheduled UEs start moving faster than a few km / h relative to the base station. One of the main reasons is that when this happens, the channel information used to calculate the MIMO precoding at the base station becomes outdated relatively quickly. Therefore, when transmitting to the target user, the precoder loses its effectiveness in protecting the co-scheduled users from interference. Therefore, downlink MU-MIMO precoding needs to be more robust for higher UE speeds.

[0028] One solution to mitigate this problem and cope with such rapid channel changes is to configure faster CSI reporting (i.e. more frequent CSI reporting and measurements). The problem with this approach is the large signaling and reporting overhead. Therefore, using the current CSI framework in NR, it is difficult to obtain accurate CSI for medium and high-speed UEs with a reasonable amount of overhead.

[0029] The goal of the 3GPP Rel-18 work item MIMO Evolution for Downlink and Uplink (3GPP RP-213598) is to study and, if justified, specify CSI reporting enhancements for high / medium UE speeds by using time-domain correlation / Doppler domain information to assist downlink precoding. Summary of the invention

[0030] As described above, there are currently certain challenges with channel state information (CSI) reporting for a Type II precoder for a user equipment (UE) traveling at high speeds. Certain aspects of the present disclosure and embodiments thereof may provide solutions to these or other challenges.

[0031] For example, certain embodiments include a refinement of the 3rd Generation Partnership Project (3GPP) Type II codebook that uses Doppler domain information to make channel state information (CSI) more useful to mobile UEs. Certain embodiments are based on enhancing the Type II codebook structure by compressing the matrix in the Doppler domain (DD) to capture the temporal variation of the channel. This also means that the matrix of linear combination coefficients becomes a three-dimensional matrix combining selected spatial domain (SD), frequency domain (FD), and DD basis vectors. Certain embodiments include methods for obtaining a matrix of linear combination coefficients and predicting future precoders based on such CSI reports.

[0032] According to some embodiments, a method for CSI reporting performed by a UE includes: the UE receives a configuration of an NZP CSI-RS resource span at multiple time instances for channel measurement, and receives a configuration for CSI reporting associated with the configured NZP CSI-RS resources, wherein one of the following sets of contents is configured to be reported in the same report, which can be used by the gNB to predict a type II precoder.

[0033] The method further includes estimating linear combination coefficients based on multiple CSI-RS instances, the linear combination coefficients being used to combine SD basis, FD basis and DD basis. The linear combination coefficients can be represented by a three-dimensional matrix. The method includes constructing a DD basis when the CSI-RS instances that can be used to estimate the linear combination coefficients are evenly spaced in time, or when the CSI-RS instances that can be used to estimate the linear combination coefficients are unevenly spaced in time, wherein the DD basis is obtained by resampling the DFT vector at the index corresponding to the CSI-RS time instance.

[0034] The method further includes selecting a subset of the SD basis, the FD basis, and the DD basis, and a predictive precoder based on a selection criterion, wherein prediction is performed using linear combination coefficients, the SD basis, the FD basis, and the DD basis, and optionally using the predicted precoder to predict a channel quality indicator.

[0035] The method further includes: reporting: a subset of SD, FD and DD basis indices together with corresponding linear combination coefficients; a predicted precoder, wherein prediction is performed using the linear combination coefficients, the SD basis, the FD basis and the DD basis; and a channel quality indicator predicted using the predicted precoder.

[0036] According to some embodiments, a method for precoder prediction performed by a gNB includes: the gNB configuring a NZP CSI-RS resource span at multiple time instances for channel measurement to a UE, and configuring a CSI reporting associated with the configured NZP CSI-RS resource to the UE, wherein one of the following content sets is configured to be reported in the same report: SD, FD, and DD base indices together with corresponding linear combination coefficients.

[0037] The above options indicate example contents to be reported in the CSI report, and other contents may also be reported, such as a rank indicator (RI) and a channel quality indicator (CQI).

[0038] The method further includes: the gNB receives the configured CSI report from the UE, and uses the reported SD, FD, DD base indexes and corresponding linear combination coefficients to predict the precoder.

[0039] According to some embodiments, a method for channel state information (CSI) reporting performed by a wireless device includes: measuring multiple instances of a CSI reference signal (CSI-RS) over a time instance span; estimating linear combination coefficients based on the measurements of the multiple CSI-RS instances, the linear combination coefficients being used to combine a spatial domain (SD) basis, a frequency domain (FD) basis, and a Doppler domain (DD) basis; and predicting a precoder using the linear combination coefficients, the SD basis, the FD basis, and the DD basis.

[0040] In a particular embodiment, the method further comprises reporting the predicted precoder to the network node.The method may comprise reporting an indication of the SD basis, the FD basis, the DD basis and the corresponding linear combination coefficients to the network node.

[0041] In certain embodiments, the method further includes predicting a channel quality indicator (CQI) using the predicted precoder and reporting the predicted CQI to the network node.

[0042] In a specific embodiment, the method further comprises: selecting a subset of SD basis, FD basis and DD basis based on a selection criterion, wherein predicting the precoder is based on the selected subset; and reporting the selected subset of SD basis, FD basis and DD basis to the network node.

[0043] In a specific embodiment, the linear combination coefficients are represented by a three-dimensional matrix, where elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

[0044] In certain embodiments, the multiple instances of the CSI-RS are evenly spaced in time. In certain embodiments, the multiple instances of the CSI-RS are unevenly spaced in time, and the Doppler basis vectors are modified to match the measurement instances.

[0045] In a particular embodiment, the method further comprises receiving, from the network node, a measurement configuration for measuring multiple instances of CSI-RS over a time instance span and / or a configuration for reporting CSI associated with multiple instances of CSI-RS over a time instance span.

[0046] According to some embodiments, a wireless device comprises a processing circuit operable to perform any of the methods of the wireless device described above.

[0047] Also disclosed is a computer program product comprising a non-transitory computer readable medium storing computer readable program code, which when executed by a processing circuit is operable to perform any of the methods performed by the wireless device described above.

[0048] According to some embodiments, a method for configuring a wireless device for CSI reporting is performed by a network node. The method includes sending a measurement configuration for measuring multiple instances of a CSI-RS over a time instance span and a configuration for reporting CSI associated with the multiple instances of the CSI-RS over the time instance span to the wireless device, and receiving a CSI report associated with the multiple instances of the CSI-RS over the time instance span from the wireless device. The CSI report includes an indication of an estimate of linear combination coefficients based on measurements of the multiple CSI-RS instances performed by the wireless device, the linear combination coefficients being used to combine an SD basis, an FD basis, and a DD basis. The method further includes predicting a precoder using the linear combination coefficients, the SD basis, the FD basis, and the DD basis.

[0049] In certain embodiments, the method further includes predicting a channel quality indicator (CQI) using the predicted precoder.

[0050] In a specific embodiment, the linear combination coefficients are represented by a three-dimensional matrix, where elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

[0051] In certain embodiments, the multiple instances of the CSI-RS are evenly spaced in time. In certain embodiments, the multiple instances of the CSI-RS are unevenly spaced in time, and the Doppler basis vectors are modified to match the measurement instances.

[0052] Another computer program product includes a non-transitory computer readable medium storing computer readable program code, which, when executed by a processing circuit, is operable to perform any of the methods performed by the network node described above.

[0053] Certain embodiments may provide one or more of the following technical advantages. For example, according to certain embodiments, Type II CSI becomes more robust to channel variations caused by, for example, mobile UEs. CSI reports may be used to predict future precoders to improve performance for mobile UEs without incurring excessive reporting overhead. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] For a more complete understanding of the disclosed embodiments and their features and advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0055] Figure 1 is a block diagram illustrating a transmission structure of a precoded spatial multiplexing mode in New Radio (NR);

[0056] Figure 2 is a time-frequency diagram showing an example of channel state information reference signal (CSI-RS) resource element (RE) allocation for 12-port CSI-RS in NR;

[0057] Figure 3 is a timing diagram showing a plurality of CSI-R samples spaced evenly apart;

[0058] Figure 4 According to a specific embodiment, matrix;

[0059] Figure 5 The three-dimensional coefficient matrix according to a specific embodiment is shown

[0060] Figure 6 is a timing diagram illustrating evenly spaced bursts of a pair of CSI-RS according to some embodiments.

[0061] Figure 7 illustrates an example communication system according to certain embodiments;

[0062] Figure 8 An example UE according to certain embodiments is shown;

[0063] Fig. 9 illustrates an example network node according to certain embodiments;

[0064] Fig.10 shows a block diagram of a host according to some embodiments;

[0065] Fig.11 illustrates a virtualized environment according to some embodiments, wherein functions implemented by some embodiments may be virtualized;

[0066] Fig.12 A host is shown communicating with a UE via a network node over a partially wireless connection according to certain embodiments;

[0067] Fig.13 A method performed by a wireless device according to some embodiments is shown; and

[0068] Fig.14 A method performed by a network node according to some embodiments is shown. DETAILED DESCRIPTION

[0069] As described above, there are currently certain challenges with channel state information (CSI) reporting for Type II precoders for high-speed user equipment (UE). Certain aspects of the present disclosure and embodiments thereof may provide solutions to these or other challenges.

[0070] For example, certain embodiments include a refinement of the 3rd Generation Partnership Project (3GPP) Type II codebook that uses Doppler domain information to make channel state information (CSI) more useful to mobile UEs. Certain embodiments are based on enhancing the Type II codebook structure by compressing the matrix in the Doppler domain (DD) to capture the temporal variation of the channel. This also means that the matrix of linear combination coefficients becomes a three-dimensional matrix that combines selected spatial domain (SD), frequency domain (FD), and DD basis vectors. Certain embodiments include a matrix for obtaining linear combination coefficients and a method for predicting future precoders based on such CSI reports.

[0071] Specific embodiments are more fully described with reference to the accompanying drawings. However, other embodiments are also included within the scope of the subject matter disclosed herein, and the disclosed subject matter should not be interpreted as being limited to the embodiments described herein; on the contrary, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0072] The Rel-16 Type II conventional codebook has the following structure Where W1 is the spatial domain (SD) compression matrix, W f is the frequency domain (FD) compression matrix, is the matrix of linear combination coefficients, and (.) H Rel-16 and Rel-17 Type II port selection codebooks have the same structure, however, in this case, W1 is the port selection matrix.

[0073] The 3GPP Rel-18 MIMO Evolution Work Item Description proposes a refinement of the Rel-16 / 17 II codebook without modifying the spatial and frequency domain bases. This means that W1 and W fThe matrices should be considered fixed, i.e., they should not change with the time instance used to exploit the time / Doppler domain information. This is probably due to the assumption that the angles and delays of the channel clusters vary relatively slowly over time. Therefore, the codebook refinement should capture small-scale fading within the channel stationary time.

[0074] In order to use the time / Doppler domain information, multiple CSI reference signal (CSI-RS) instances in time are needed to construct the CSI report. Figure 3 An example of multiple CSI-RS instances is shown in FIG.

[0075] Figure 3 is a timing diagram showing multiple CSI-RS samples that are evenly spaced. A UE may use multiple CSI-RS samples to estimate the time domain properties of a channel.

[0076] In some embodiments, before discarding or quantizing any coefficients to reduce feedback overhead, let is the matrix of linear combination coefficients calculated using CSI-RS instance q for all SD and FD basis vectors.

[0077] In some embodiments, before discarding or quantizing any coefficients to reduce feedback overhead, let is the matrix of linear combination coefficients computed using CSI-RS instance q for the selected subset of the strongest SD and FD basis vectors.

[0078] The coefficient matrix for q = 0 to q = Q-1 can be fed back directly to the network. However, to reduce reporting overhead, certain embodiments use a Doppler domain (DD) basis to compress these coefficient matrices. This can be seen as an extension of the spatial and frequency domain compression in the Rel-16 Type II codebook to also include DD compression.

[0079] Figure 4 According to a specific embodiment, Matrix. Let Representation coefficient matrix The elements in the lth row and mth column of , which correspond to the weights of the lth SD basis and the mth FD basis. Figure 4 The stacking of CSI-RS instances is shown in FIG. They are calculated based on the CSI-RS instances.

[0080] coefficient The time evolution of the vector capture.

[0081] Let W D represents a matrix, where each column is a DD basis vector. In some embodiments, W DW is a discrete Fourier transform (DFT) matrix of size Q×Q, where the columns represent orthogonal DD basis vectors. D The dth column of has the following form:

[0082] In some embodiments, the UE calculates a three-dimensional coefficient matrix Here, the element indicates the weight used to combine the SD basis, the FD basis, and the DD basis.

[0083] In some embodiments, the user node calculates The elements of Among them, W D (:,d) indicates W D In the d-th column of the matrix, l is the SD basis index, m is the FD basis index, and d is the DD basis index.

[0084] Figure 5 shows a three-dimensional coefficient matrix according to a specific embodiment

[0085] In some embodiments, the CSI report from the UE node is composed of SD base index of W1, W f The FD base index and W D The DD base index is composed of .

[0086] In some embodiments, The compression is done by discarding those whose magnitude is below a threshold. The UE reports the index of the SD, FD and DD bases corresponding to the non-discarded elements. In a related embodiment, the UE feedback indicates the non-discarded A bitmap of the element is included with the CSI report.

[0087] In some embodiments, at a network node, from Construct a precoder W for future time instances pred .

[0088] In some embodiments, at a user node, from Construct precoder W pred .

[0089] In some embodiments, a precoder W is used at the user node pred To determine a channel quality indicator (CQI).

[0090] In some embodiments, for a time interval Δt, the prediction precoder W pred, the time interval Δt represents the time interval between receiving the CSI-RS instance with index q=0 at the user node and receiving the CSI-RS instance with index q=0 at the network node or the user node from the SD base index, the FD base index, the DD base index and For the precoder W pred The time difference or estimated time difference between the predicted times.

[0091] Operation 1: Let f d denotes the continuous-time equivalent frequency of the d-th Doppler basis. Let x d (Δt) represents the d-th Doppler domain basis sampled at Δt, and it is given by Given.

[0092] Operation 2: Construct the corresponding to Δt for where α is a normalization factor used to account for the number of DD bases.

[0093] Operation 3: Construct W1 and W2 from the SD base index and FD base index respectively. Then, the predicted precoder is given by Given.

[0094] In some embodiments, Δt represents the time between receiving a CSI-RS instance with index q=0 at the user node and calculating the precoder W with the help of the timing advance information available at the network node. pred The time difference between the predicted times.

[0095] In some embodiments, Δt represents the difference between sending a CSI-RS instance with index q=0 at the user node and sending it at the precoder W pred The time difference between the predicted times.

[0096] In some embodiments, at the network node, a predictive precoder W is used for each orthogonal frequency division multiplexing (OFDM) symbol in a downlink transmission using Δt equal to the time difference between receiving a CSI-RS instance with index q=0 and the start time of the OFDM symbol. pred .

[0097] If the spacing of CSI-RS time samples is non-uniform, the Doppler basis vector can be modified to match the sampling instants. The non-uniform spacing may be due to, for example, non-periodic triggering of CSI-RS or limitations in possible periodic CSI-RS resource allocation. It is also advantageous to have non-uniform sparse sampling to reduce RS overhead and Doppler ambiguity issues.

[0098] If the Doppler basis is the DFT matrix, then if the sampling is uniform, the kth basis vector has element e -j2πkn / N, n=0,1,…N. Now, assume that there is a uniform grid of N time samples {0,1,2,…,N-1}, on which only a subset of Q samples is occupied by CSI-RS, and let n q represents the time sample for the qth CSI-RS time instance. Then the DFT basis vector needs to be modified to have elements For example, consider the case of four evenly spaced bursts of a pair of CSI-RS. Figure 6 An example is shown in .

[0099] Figure 6 is a timing diagram showing evenly spaced bursts of a pair of CSI-RS. In the example shown, n q ∈{0,1,6,7,12,13,18,19}, Q=8 and N=20.

[0100] In some embodiments, the spacing of CSI-RS time samples is non-uniform and the Doppler basis vectors are modified to match the sampling instants.

[0101] In some embodiments, when the Doppler domain basis is based on a DFT vector and the CSI-RS time samples are non-uniformly spaced, the DFT vector is resampled at the index corresponding to the CSI-RS time instance.

[0102] Figure 7 An example of a communication system 100 according to some embodiments is shown. In this example, the communication system 100 includes a telecommunications network 102, which includes an access network 104 (e.g., a radio access network (RAN)) and a core network 106 (including one or more core network nodes 108). The access network 104 includes one or more access network nodes, such as network nodes 110a and 110b (one or more of which may be generally referred to as network nodes 110), or any other similar third generation partnership project (3GPP) access node or non-3GPP access point. The network node 110 facilitates direct or indirect connection of user equipment (UE), such as connecting UE 112a, 112b, 112c, and 112d (one or more of which may be generally referred to as UE 112) to the core network 106 via one or more wireless connections.

[0103] Example wireless communications over wireless connections include sending 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. Additionally, in various embodiments, the communication system 100 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 over a wired or wireless connection. The communication system 100 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar types of systems.

[0104] The UE 112 may be any of a variety of communication devices, including wireless devices that are arranged, configured and / or operable to wirelessly communicate with the network node 110 and other communication devices. Similarly, the network node 110 is arranged, capable, configured and / or operable to communicate directly or indirectly with the UE 112 and / or other network nodes or devices in the telecommunications network 102 to enable and / or provide network access (e.g., wireless network access) and / or perform other functions (e.g., management in the telecommunications network 102).

[0105] In the depicted example, the core network 106 connects the network node 110 to one or more hosts (e.g., host 116). These connections may be direct, or may be indirect via one or more intermediate networks or devices. In other examples, the network node may be directly coupled to the host. The core network 106 includes one or more core network nodes (e.g., core network node 108), which are composed of hardware and software components. The features of these components may be substantially similar to the features described for the UE, network node, and / or host, so that their description is generally applicable to the corresponding components of the core network node 108. Example core network nodes include the functions of one or more of a mobile switching center (MSC), a mobility management entity (MME), a home subscriber server (HSS), an access and mobility management function (AMF), a session management function (SMF), an authentication server function (AUSF), a subscription identifier decryption function (SIDF), a unified data management (UDM), a security edge protection agent (SEPP), a network open function (NEF), and / or a user plane function (UPF).

[0106] The host 116 may be owned or controlled by a service provider other than the operator or provider of the access network 104 and / or the telecommunications network 102, and may be operated by or on behalf of the service provider. The host 116 may host various applications to provide one or more services. Examples of such applications include live and pre-recorded audio / video content, data collection services (e.g., retrieving and compiling data about various environmental conditions detected by multiple UEs), analytical functions, social media, functions for controlling or otherwise interacting with remote devices, functions for alarm and monitoring centers, or any other such functions performed by a server.

[0107] Overall, Figure 7 The communication system 100 in the embodiment enables connections between UEs, network nodes, and hosts. In this sense, the communication system can be configured to operate according to predefined rules or procedures, such as specific standards, including but 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 standards (e.g., 6G); Wireless Local Area Network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard (WiFi); and / or any other suitable wireless communication standards, such as 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.

[0108] In some examples, the telecommunication network 102 is a cellular network that implements 3GPP standardized features. Thus, the telecommunication network 102 can support network slicing to provide different logical networks to different devices connected to the telecommunication network 102. For example, the telecommunication network 102 can provide ultra-reliable low-latency communication (URLLC) services to some UEs while providing enhanced mobile broadband (eMBB) services to other UEs, and / or provide massive machine type communication (mMTC) / massive IoT services to other UEs.

[0109] In some examples, UE 112 is configured to send and / or receive information without direct human interaction. For example, the UE can be designed to send information to access network 104 according to a predetermined schedule, when triggered by an internal or external event, or in response to a request from access network 104. In addition, the UE can be configured to operate in a single RAT or multi-RAT or multi-standard mode. For example, the UE can operate using any one or a combination of Wi-Fi, NR (New Radio), and LTE, i.e., configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved UMTS Terrestrial Radio Access Network) New Radio-Dual Connectivity (EN-DC).

[0110] In this example, the hub 114 communicates with the access network 104 to facilitate indirect communication between one or more UEs (e.g., UE 112c and / or 112d) and a network node (e.g., network node 110b). In some examples, the hub 114 can be a controller, a router, a content source, and an analyzer, or any other communication device described herein with respect to the UE. For example, the hub 114 can be a broadband router that enables the UE to access the core network 106. As another example, the hub 114 can be a controller that sends commands or instructions to one or more actuators in the UE. The commands or instructions can be received from the UE, the network node 110, or received through executable code, scripts, processes, or other instructions in the hub 114. As another example, the hub 114 can be a data collector that acts as a temporary storage for UE data, and in some embodiments, analysis or other processing of the data can be performed. As another example, the hub 114 can be a content source. For example, for a UE that is a VR headset, display, speaker, or other media delivery device, the hub 114 can retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, and then the hub 114 provides it to the UE directly, after performing local processing, and / or adding other local content. In another example, the hub 114 acts as a proxy server or coordinator for the UE, especially when one or more UEs are low-energy IoT devices.

[0111] The hub 114 may have a constant / persistent or intermittent connection with the network node 110b. The hub 114 may also allow different communication schemes and / or scheduling between the hub 114 and the UE (e.g., UE 112c and / or 112d) and between the hub 114 and the core network 106. In other examples, the hub 114 is connected to the core network 106 and / or one or more UEs via a wired connection. In addition, the hub 114 may be configured to be connected to the M2M service provider and / or to another UE via a direct connection via the access network 104. In some scenarios, the UE may establish a wireless connection with the network node 110 while still being connected via the hub 114 via a wired or wireless connection. In some embodiments, the hub 114 may be a dedicated hub, that is, the hub's main function is to route communication from the network node 110b to the UE or to route communication from the UE to the network node 110b. In other embodiments, the hub 114 may be a non-dedicated hub, ie, a device operable to route communications between UEs and the network node 110b, but which is additionally capable of operating as a communications origin and / or endpoint for certain data channels.

[0112] Figure 8 UE 200 according to some embodiments is shown. As used herein, UE refers to a device capable of, configured, arranged and / or operable to wirelessly communicate with a network node and / or other UEs. Examples of UEs include, but are not limited to, smartphones, mobile phones, cellular phones, voice over IP (VoIP) phones, wireless local loop phones, desktop computers, personal digital assistants (PDAs), wireless cameras, game consoles or devices, music storage devices, playback devices, wearable terminal devices, wireless endpoints, mobile stations, tablet computers, laptops, laptop embedded devices (LEEs), laptop mounted devices (LMEs), smart devices, wireless client equipment (CPEs), vehicle-mounted or vehicle-mounted embedded / integrated wireless devices, etc. Other examples include any UE identified by the Third Generation Partnership Project (3GPP), including narrowband Internet of Things (NB-IoT) UEs, machine type communications (MTC) UEs, and / or enhanced MTC (eMTC) UEs.

[0113] For example, a UE may support device-to-device (D2D) communications by implementing 3GPP standards for sidelink communications, dedicated short-range communications (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 associated device. Instead, a UE may represent a device that is intended to be sold to or operated by a human user, but may not be associated with a specific human user, or 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 to be sold to or operated by an end user, but may be associated with or operated for the benefit of a user (e.g., a smart meter).

[0114] UE 200 includes processing circuitry 202, which is operatively coupled to input / output interface 206, power supply 208, memory 210, communication interface 212, and / or any other components, or any combination thereof, via bus 204. Some UEs may use Figure 8 All or a subset of the components shown in . The degree of integration between components may vary from UE to UE. In addition, some UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0115] The processing circuit 202 is configured to process instructions and data, and may be configured to implement any sequential state machine that is operable to execute instructions stored in the memory 210 as a machine-readable computer program. The processing circuit 202 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 (e.g., microprocessors or digital signal processors (DSPs)) together with appropriate software; or any combination of the above. For example, the processing circuit 202 may include multiple central processing units (CPUs).

[0116] In this example, the input / output interface 206 can be configured to provide one or more interfaces to an input device, an output device, or one or more input and / or output devices. Examples of output devices include speakers, sound cards, video cards, displays, monitors, printers, actuators, transmitters, smart cards, another output device, or any combination thereof. An input device can allow a user to capture information into the UE 200. Examples of input devices include touch-sensitive or presence-sensitive displays, cameras (e.g., digital cameras, digital video cameras, web cameras, etc.), microphones, sensors, mice, trackballs, directional keys, trackpads, scroll wheels, smart cards, etc. A presence-sensitive display can include a capacitive or resistive touch sensor to sense input from a user. The sensor can be, for example, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biosensor, etc., or any combination thereof. An output device can use an interface port of the same type as an input device. For example, a universal serial bus (USB) port can be used to provide input devices and output devices.

[0117] In some embodiments, the power supply 208 is configured as a battery or a battery pack. Other types of power supplies may be used, such as an external power supply (e.g., a power outlet), a photovoltaic device, or a battery. The power supply 208 may also include a power supply circuit for delivering power from the power supply 208 itself and / or an external power supply to various parts of the UE 200 via an input circuit or interface (e.g., a power cable). The delivered power may be used, for example, to charge the power supply 208. The power supply circuit may perform any formatting, conversion, or other modification on the power from the power supply 208 to make the power suitable for the various components of the UE 200 to be powered.

[0118] The memory 210 may be or be configured to include a memory such as a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic disk, an optical disk, a hard disk, a removable cartridge, a flash drive, etc. In one example, the memory 210 includes one or more applications 214, such as an operating system, a web browser application, a widget, a gadget engine, or other applications, and corresponding data 216. The memory 210 may store any of a variety of operating systems or combinations of operating systems for use by the UE 200.

[0119] The memory 210 may be configured to include a plurality of physical drive units, such as a redundant array of independent disks (RAID), a flash memory, a USB flash drive, an external hard drive, a thumb drive, a pen drive, a key drive, a high-density digital versatile disc (HD-DVD) optical drive, an internal hard drive, a Blu-ray optical drive, a holographic digital data storage (HDDS) optical drive, an external micro dual in-line memory module (DIMM), a synchronous dynamic random access memory (SDRAM), an external micro DIMM SDRAM, a smart card memory (e.g., a tamper-proof module in the form of a universal integrated circuit card (UICC), including one or more subscriber identity modules (SIMs), such as USIM and / or ISIM), other memories, or any combination thereof. The UICC may be an embedded UICC (eUICC), an integrated UICC (iUICC), or a removable UICC commonly referred to as a "SIM card". The memory 210 may allow the UE 200 to access instructions, applications, etc. stored on a temporary or non-temporary storage medium to offload data or upload data. An article of manufacture (eg, an article of manufacture utilizing a communication system) may be tangibly embodied as or located in memory 210, which may be or include a device-readable storage medium.

[0120] The processing circuit 202 may be configured to communicate with an access network or other network using a communication interface 212. The communication interface 212 may include one or more communication subsystems and may include or be communicatively coupled to an antenna 222. The communication interface 212 may include one or more transceivers, which are used for communication, for example, by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or network node in the access network). Each transceiver may include a transmitter 218 and / or a receiver 220 suitable for providing network communications (e.g., optical, electrical, frequency allocation, etc.). In addition, the transmitter 218 and the receiver 220 may be coupled to one or more antennas (e.g., antenna 222) and may share circuit components, software, or firmware, or may be implemented separately.

[0121] In the illustrated embodiment, the communication functions of the communication interface 212 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communication (e.g., Bluetooth), near field communication, location-based communication (e.g., using a global positioning system (GPS) to determine location), other similar communication functions, or any combination thereof. Communication may be implemented according to one or more communication protocols and / or standards, such as IEEE 802.11, code division multiple access (CDMA), wideband code division multiple access (WCDMA), GSM, LTE, new radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / Internet protocol (TCP / IP), synchronous optical network (SONET), asynchronous transfer mode (ATM), QUIC, hypertext transfer protocol (HTTP), etc.

[0122] Regardless of the sensor type, the UE may provide an output of data captured by its sensor to a network node via a wireless connection through its communication interface 212. The data captured by the UE's sensor may be transmitted to the network node via another UE via a wireless connection. The output may be periodic (e.g., every 15 minutes if it reports a sensed temperature), random (e.g., to balance the load of reports from multiple sensors), in response to a trigger event (e.g., sending an alarm when moisture is detected), in response to a request (e.g., a user-initiated request), or a continuous stream (e.g., a live video feed of a patient).

[0123] As another example, the UE includes an actuator, motor, or switch associated with a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input, the state of the actuator, motor, or switch can change. For example, the UE can include a motor that adjusts a control surface or rotor of a drone in flight based on the received input, or adjusts a robotic arm performing a medical procedure based on the received input.

[0124] When the UE is in the form of an Internet of Things (IoT) device, it can be a device for one or more application areas, including but not limited to urban wearable technology, extended industrial applications, and healthcare. Non-limiting examples of such IoT devices are the following devices or the following devices embedded therein: connected refrigerators or freezers, televisions, connected lighting devices, electricity meters, robotic vacuum cleaners, voice-controlled smart speakers, home security cameras, motion detectors, thermostats, smoke detectors, door / window sensors, flood / humidity sensors, electric door locks, connected doorbells, air conditioning systems (such as heat pumps), self-driving cars, surveillance systems, weather monitoring devices, vehicle parking monitoring devices, electric vehicle charging stations, smart watches, fitness trackers, head-mounted displays for augmented reality (AR) or virtual reality (VR), wearable devices for tactile enhancement or sensory enhancement, sprinklers, animal or item tracking devices, sensors for monitoring plants or animals, industrial robots, unmanned aerial vehicles (UAVs), and any type of medical equipment (such as heart rate monitors or remote-controlled surgical robots). UEs in the form of IoT devices include, in addition to those with Figure 8 In addition to other components described in relation to the UE 200 shown in FIG. 1 , the UE 200 further includes circuits and / or software depending on the intended application of the IoT device.

[0125] As another specific example, in an IoT scenario, a UE may represent a machine or other device that performs monitoring and / or measurement and sends the results of such monitoring and / or measurement to another UE and / or a network node. In this case, the UE may be an M2M device, which may be referred to as an MTC device in the 3GPP context. As a specific example, a UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, bus, truck, ship, and airplane, or other device capable of monitoring and / or reporting its operating status or other functions related to its operation.

[0126] In practice, any number of UEs may be used together for a single use case. For example, a first UE may be a drone or integrated into a drone and provide the drone's speed information (obtained via a speed sensor) to a second UE, which is a remote controller that operates the drone. When a 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 UE and / or the second UE may also include multiple of the above-described functions. For example, a UE may include sensors and actuators and handle communication of data for the speed sensor and actuator.

[0127] Fig. 9A network node 300 according to some embodiments is shown. As used herein, a network node refers to a device capable of, configured, arranged and / or operable to communicate directly or indirectly with a UE and / or other network nodes or devices in a telecommunications network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., wireless base stations, Node Bs, evolved Node Bs (eNBs), and NR Node Bs (gNBs)).

[0128] Base stations can be classified according to the amount of coverage they provide (or in other words, their transmit power level), and therefore, depending on the amount of coverage provided, can be called a femto base station, a pico base station, a micro base station, or a macro base station. A base station can be a relay node or a relay donor node that controls a relay. A network node may also include one or more (or all) parts of a distributed radio base station, such as a centralized digital unit and / or a remote radio unit (RRU), sometimes referred to as a remote radio head (RRH). Such a remote radio unit may be integrated with an antenna as an integrated radio or may not be integrated with an antenna. The various parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

[0129] Other examples of network nodes include a multi-transmission point (multi-TRP) 5G access node, a multi-standard radio (MSR) device (e.g., an MSR BS), a network controller (e.g., a radio network controller (RNC) or a base station controller (BSC), a base transceiver station (BTS), a transmission point, a transmission node, a multi-cell / multicast coordination entity (MCE), an operation and maintenance (O&M) node, an operation support system (OSS) node, a self-organizing network (SON) node, a positioning node (e.g., an evolved serving mobile positioning center (E-SMLC)) and / or a minimization of drive tests (MDT).

[0130] The network node 300 includes a processing circuit 302, a memory 304, a communication interface 306, and a power supply 308. The network node 300 may be composed of multiple physically independent components (e.g., a NodeB component and an RNC component, or a BTS component and a BSC component, etc.), each of which may have its own components. In certain scenarios where the network node 300 includes multiple independent components (e.g., BTS and BSC components), one or more of the independent components may be shared between multiple network nodes. For example, a single RNC may control multiple NodeBs. In this case, each unique NodeB and RNC pair may be considered a single independent network node in some cases. In some embodiments, the network node 300 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be repeated (e.g., separate memories 304 for different RATs), and some components may be reused (e.g., different RATs may share the same antenna 310). The network node 300 may also include various sets of components shown for different wireless technologies, such as GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, radio frequency identification (RFID), or Bluetooth wireless technologies, integrated into the network node 300. These wireless technologies may be integrated into the same or different chips or chipsets and other components within the network node 300.

[0131] The processing circuit 302 may include a combination of one or more of a microprocessor, a controller, a microcontroller, a central processing unit, a digital signal processor, an application specific integrated circuit, a field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and / or encoded logic, which may be used alone or in combination with other network node 300 components (e.g., memory 304) to provide network node 300 functionality.

[0132] In some embodiments, processing circuitry 302 includes a system on a chip (SOC). In some embodiments, processing circuitry 302 includes one or more radio frequency (RF) transceiver circuitry 312 and baseband processing circuitry 314. In some embodiments, radio frequency (RF) transceiver circuitry 312 and baseband processing circuitry 314 may be located on separate chips (or chipsets), circuit boards, or units, such as a radio unit and a digital unit. In alternative embodiments, part or all of RF transceiver circuitry 312 and baseband processing circuitry 314 may be located on the same chip or chipset, circuit board, or unit.

[0133] Memory 304 may include any form of volatile or non-volatile computer-readable memory, including but not limited to persistent memory, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (e.g., hard disk), removable storage media (e.g., flash drive, compact disk (CD) or digital video disk (DVD)), and / or any other volatile or non-volatile, non-transitory device-readable and / or computer-executable memory device for storing information, data and / or instructions that can be used by processing circuit 302. Memory 304 may store any suitable instructions, data or information, including computer programs, software, applications, including one or more logic, rules, codes, tables and / or other instructions that can be executed by processing circuit 302 and utilized by network node 300. Memory 304 may be used to store any calculations performed by processing circuit 302 and / or any data received via communication interface 306. In some embodiments, processing circuit 302 and memory 304 are integrated.

[0134] The communication interface 306 is used for wired or wireless communication and / or data between network nodes, access networks and / or UEs. As shown, the communication interface 306 includes a port / terminal 316 for sending and receiving data to the network, for example, via a wired connection. The communication interface 306 also includes a radio front-end circuit 318, which can be coupled to the antenna 310, or in some embodiments is a part of the antenna 310. The radio front-end circuit 318 includes a filter 320 and an amplifier 322. The radio front-end circuit 318 can be connected to the antenna 310 and the processing circuit 302. The radio front-end circuit can be configured to adjust the signal transmitted between the antenna 310 and the processing circuit 302. The radio front-end circuit 318 can receive digital data to be sent to other network nodes or UEs via a wireless connection. The radio front-end circuit 318 can use a combination of a filter 320 and / or an amplifier 322 to convert the digital data into a radio signal with appropriate channel and bandwidth parameters. The radio signal can then be sent via the antenna 310. Similarly, when receiving data, antenna 310 may collect radio signals, which may then be converted to digital data by radio front end circuitry 318. The digital data may be passed to processing circuitry 302. In other embodiments, the communication interface may include different components and / or different combinations of components.

[0135] In some alternative embodiments, the network node 300 does not include a separate radio front end circuit 318, but rather, the processing circuit 302 includes the radio front end circuit and is connected to the antenna 310. Similarly, in some embodiments, all or part of the RF transceiver circuit 312 is part of the communication interface 306. In still other embodiments, the communication interface 306 includes one or more ports or terminals 316, the radio front end circuit 318, and the RF transceiver circuit 312 as part of a radio unit (not shown), and the communication interface 306 communicates with the baseband processing circuit 314, which is part of the digital unit (not shown).

[0136] Antenna 310 may include one or more antennas or antenna arrays configured to send and / or receive wireless signals. Antenna 310 may be coupled to radio front end circuitry 318 and may be any type of antenna capable of wirelessly sending and receiving data and / or signals. In some embodiments, antenna 310 is separate from network node 300 and may be connected to network node 300 via an interface or port.

[0137] The antenna 310, the communication interface 306 and / or the processing circuit 302 may be configured to perform any receiving operation and / or certain obtaining operations performed by the network node described herein. Any information, data and / or signal may be received from the UE, another network node and / or any other network device. Similarly, the antenna 310, the communication interface 306 and / or the processing circuit 302 may be configured to perform any sending operation performed by the network node described herein. Any information, data and / or signal may be sent to the UE, another network node and / or any other network device.

[0138] The power supply 308 provides power to the various components of the network node 300 in a form suitable for the various components (e.g., at the voltage and current levels required by each component). The power supply 308 may also include or be coupled to a power management circuit to provide power to the components of the network node 300 to perform the functions described herein. For example, the network node 300 may be connected to an external power source (e.g., an electrical grid, an electrical outlet) via an input circuit or interface (e.g., a cable), so that the external power source provides power to the power circuit of the power supply 308. As another example, the power supply 308 may include a power source in the form of a battery or battery pack that is connected to the power circuit or is integrated in the power circuit. If the external power source fails, the battery can provide backup power.

[0139] remove Fig. 9In addition to the components shown in , embodiments of network node 300 may include additional components for providing certain aspects of network node functionality, including any functionality described herein and / or any functionality required to support the subject matter described herein. For example, network node 300 may include a user interface device to allow information to be input into network node 300 and to allow information to be output from network node 300. This may allow a user to perform diagnostics, maintenance, repair, and other management functions on network node 300.

[0140] Fig.10 is a block diagram of a host 400 consistent with various aspects described herein, which may be Figure 7 1. The host 400 is an embodiment of a host 116. As used herein, the host 400 can be or include various combinations of hardware and / or software, including processing resources in a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, a container, or a server farm. The host 400 can provide one or more services to one or more UEs.

[0141] Host 400 includes processing circuitry 402, which is operably coupled to input / output interface 406, network interface 408, power supply 410, and memory 412 via bus 404. Other components may be included in other embodiments. The features of these components may be similar to those described for the devices in the previous figures (e.g., Figure 3 and 4 ) are substantially similar, so that their description is generally applicable to the corresponding components of the host 400.

[0142] The memory 412 may include one or more computer programs, including one or more host applications 414 and data 416, which may include user data, such as data generated by a UE for the host 400 or data generated by the host 400 for the UE. An embodiment of the host 400 may utilize only a subset or all of the components shown. The host application 414 may be implemented in a container-based architecture, and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for a variety of different categories, types, or implementations of UE (e.g., mobile phones, desktop computers, wearable display systems, head-up display systems). The host application 414 may also provide user authentication and license checks, and may periodically report health, routing, and content availability to a central node (e.g., a device in a core network or on the edge). Thus, the host 400 may select and / or instruct different hosts for the UE to provide over-the-top services. The host application 414 may support various protocols, such as HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), and the like.

[0143] Fig.11 500 is a block diagram showing a virtualized environment, wherein the functions implemented by certain embodiments may be virtualized. In this context, virtualization means creating a virtual version of a device or apparatus, which may include a virtualized hardware platform, storage device, and network resources. As used herein, virtualization may be applied to any device or component thereof described herein, and relates to the implementation of at least a portion of the functions being 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), which are implemented in one or more virtual environments 500 hosted by one or more hardware nodes (e.g., hardware computing devices running as network nodes, UEs, core network nodes, or hosts). In addition, in embodiments where a virtual node does not require a radio connection (e.g., a core network node or host), the node may be fully virtualized.

[0144] Application 502 (which may also be referred to as a software instance, a virtual device, a network function, a virtual node, a virtual network function, etc.) runs in a virtualized environment Q400 to implement some features, functions and / or advantages of some embodiments disclosed herein.

[0145] Hardware 504 includes processing circuitry, memory storing software and / or instructions executable by the hardware processing circuitry, and / or other hardware devices described herein, such as network interfaces, input / output interfaces, etc. The software may be executed by the processing circuitry to instantiate one or more virtualization layers 506 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 508a and 508b (one or more of which may be collectively referred to as VMs 508), and / or perform any functions, features, and / or advantages associated with some embodiments described herein. Virtualization layer 506 may present a virtual operating platform that appears to VMs 508 like network hardware.

[0146] VM 508 includes virtual processing, virtual memory, virtual network or interface and virtual storage, and can be operated by corresponding virtualization layer 506. Different embodiments of instances of virtual device 502 can be implemented on one or more VM 508, and can be implemented in different ways. Virtualization of hardware is sometimes referred to as network function virtualization (NFV). NFV can be used to integrate many network device types onto industry-standard high-capacity server hardware, physical switches and physical storage, which can be located in data centers and client devices.

[0147] In the context of NFV, a VM 508 may be a software implementation of a physical machine that runs programs as if they were executed on a physical, non-virtualized machine. Each VM 508 and the portion of the hardware 504 on which the VM executes (whether dedicated to the VM or shared with other VMs) form a separate virtual network element. Still in the context of NFV, a virtual network function is responsible for handling a specific network function running in one or more VMs 508 on top of the hardware 504 and corresponds to an application 502.

[0148] Hardware 504 may be implemented in a standalone network node with general or specific components. Hardware 504 may implement some functions via virtualization. Alternatively, hardware 504 may be part of a larger hardware cluster (e.g., in a data center or CPE) where many hardware nodes work together and are managed through management and orchestration 510, which, among other things, oversees the lifecycle management of application 502. In some embodiments, hardware 504 is coupled to one or more radio units, each of which includes one or more transmitters and one or more receivers that may be coupled to one or more antennas. The radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces, and may be used in conjunction with virtual components to provide virtual nodes with radio functionality, such as radio access nodes or base stations. In some embodiments, a control system 512 may be used to provide some signaling, which may alternatively be used for communication between hardware nodes and radio units.

[0149] Fig.12 A communication diagram is shown in which a host 602 communicates with a UE 606 via a network node 604 over a partially wireless connection according to some embodiments. Fig.12 Describing a UE (eg, Figure 7 UE 112a and / or Figure 8 UE 200), network node (e.g., Figure 7 The network node 110a and / or Fig. 9 network node 300) and a host (e.g., Figure 7 Host 116 and / or Fig.10 An example implementation of host 400).

[0150] Similar to the host 400, an embodiment of the host 602 includes hardware, such as a communication interface, a processing circuit, and a memory. The host 602 also includes software that is stored in or accessible by the host 602 and can be executed by the processing circuit. The software includes a host application that can be used to provide services to a remote user, such as a UE 606 connected via an over-the-top (OTT) connection 650 extending between the UE 606 and the host 602. When providing services to the remote user, the host application can provide user data sent using the OTT connection 650.

[0151] The network node 604 includes hardware that enables it to communicate with the host 602 and the UE 606. The connection 660 may be direct or may be through a core network (such as Figure 7 The intermediate network may be a backbone network or the Internet.

[0152] UE 606 includes hardware and software, the software is stored in UE 606 or accessible by UE 606, and can be executed by the processing circuit of UE. The software includes a client application, such as a web browser or an operator-specific "application", which is operable to provide services to human or non-human users via UE 606 with the support of host 602. In host 602, the executing host application can communicate with the executing client application via an OTT connection 650 terminated at UE 606 and host 602. When providing services to the user, the client application of the UE can receive request data from the host application of the host and provide user data in response to the request data. The OTT connection 650 can send both request data and user data. The client application of the UE can interact with the user to generate user data, which is provided to the host application via the OTT connection 650.

[0153] The OTT connection 650 may extend via a connection 660 between the host 602 and the network node 604 and a wireless connection 670 between the network node 604 and the UE 606 to provide connectivity between the host 602 and the UE 606. The connection 650 and the wireless connection 660, 670 through which the OTT connection may be provided, are drawn abstractly to illustrate communications between the host 602 and the UE 606 via the network node 604 without explicit reference to any intermediate devices and the precise routing of messages via those devices.

[0154] As an example of sending data via the OTT connection 650, in operation 608, the host 602 provides user data, which can be performed by executing a host application. In some embodiments, the user data is associated with a specific human user interacting with the UE 606. In other embodiments, the user data is associated with the UE 606 that shares data with the host 602 without explicit human interaction. In operation 610, the host 602 initiates a transmission carrying the user data to the UE 606. The host 602 may initiate the transmission in response to a request sent by the UE 606. The request may be caused by human interaction with the UE 606, or may be caused by the operation of a client application running on the UE 606. According to the teachings of the embodiments described throughout the present disclosure, the transmission may be delivered via the network node 604. Therefore, in operation 612, according to the teachings of the embodiments described throughout the present disclosure, the network node 604 sends the user data carried in the transmission initiated by the host 602 to the UE 606. In operation 614 , the UE 606 receives the user data carried in the transmission, which operation may be performed by a client application running on the UE 606 , which is associated with a host application running on the host 602 .

[0155] In some examples, UE 606 runs a client application that provides user data to host 602. The user data may be provided as a reaction or response to data received from host 602. Therefore, in operation 616, UE 606 may provide user data, which may be performed by running a client application. When providing user data, the client application may also take into account user input received from a user via an input / output interface of UE 606. Regardless of the specific manner in which user data is provided, UE 606 initiates transmission of user data to host 602 via network node 604 in operation 618. In operation 620, in accordance with the teachings of the embodiments described throughout the present disclosure, network node 604 receives user data from UE 606 and initiates transmission of the received user data to host 602. In operation 622, host 602 receives user data carried in the transmission initiated by UE 606.

[0156] One or more of the various embodiments improve the performance of OTT services provided to UE 606 using OTT connection 650, where wireless connection 670 forms the last leg. More specifically, the teachings of these embodiments can improve the latency of directly activating SCells through RRC and the power consumption of user equipment, thereby providing benefits such as reduced user waiting time and extended battery life.

[0157] In an example scenario, host 602 may collect and analyze plant status information. As another example, host 602 may process audio and video data that may have been retrieved from a UE for use in creating a map. As another example, host 602 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, host 602 may store surveillance videos uploaded by a UE. As another example, host 602 may store or control access to media content such as video, audio, VR, or AR, which may be broadcast, multicast, or unicast to a UE. As other examples, host 602 may be used for energy pricing, remote control of non-time-critical power loads to balance power generation demand, location services, presentation services (e.g., compiling charts from data collected from remote devices, etc.), or any other function that collects, retrieves, stores, analyzes, and / or transmits data.

[0158] In some examples, a measurement process may be provided for monitoring data rates, delays, and other factors that are improved by one or more embodiments. There may also be further optional network functions for reconfiguring the OTT connection 650 between the host 602 and the UE 606 in response to changes in the measurement results. The measurement process and / or the network function for reconfiguring the OTT connection may be implemented in software and hardware of the host 602 and / or the UE 606. In some embodiments, sensors (not shown) may be deployed in or associated with other devices through which the OTT connection 650 passes; the sensors may participate in the measurement process by providing the values ​​of the monitored quantities exemplified above or providing the values ​​of other physical quantities, and the software may calculate or estimate the monitored quantities from the values ​​of other physical quantities. The reconfiguration of the OTT connection 650 may include message formats, retransmission settings, preferred routes, etc.; the reconfiguration does not require direct changes to the operation of the network node 604. Such processes and functions are known and practiced in the art. In some embodiments, the measurement may involve proprietary UE signaling, which facilitates the host 602 to measure throughput, propagation time, delay, etc. Measurements may be made by software causing messages (particularly empty or "dummy" messages) to be sent using the OTT connection 650 while monitoring propagation times, errors, etc.

[0159] Fig.13 is a flow chart illustrating an example method in a wireless device according to certain embodiments. In certain embodiments, Fig.13 One or more operations in Figure 8 The UE 200 described here performs the CSI reporting.

[0160] The method may start at operation 1308, where a wireless device (e.g., UE 200) receives a measurement configuration from a network node for measuring multiple instances of a CSI-RS over a time instance span. At operation 1310, the wireless device may receive a configuration for reporting CSI associated with multiple instances of a CSI-RS over a time instance span.

[0161] At operation 1312, the wireless device measures multiple instances of CSI-RS over a time instance span. The wireless device may perform measurements according to the received measurement configuration.

[0162] At operation 1314, the wireless device estimates linear combination coefficients based on the measurements of the plurality of CSI-RS instances, the linear combination coefficients being used to combine a spatial domain (SD) basis, a frequency domain (FD) basis, and a Doppler domain (DD) basis. The wireless device may perform the estimation according to any of the embodiments and examples described herein.

[0163] In a specific embodiment, the linear combination coefficients are represented by a three-dimensional matrix, where elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

[0164] In certain embodiments, the multiple instances of the CSI-RS are evenly spaced in time. In certain embodiments, the multiple instances of the CSI-RS are unevenly spaced in time, and the Doppler basis vectors are modified to match the measurement instances.

[0165] In some embodiments, at operation 1316, the wireless device may select a subset of the SD basis, the FD basis, and the DD basis based on the selection criteria.

[0166] At operation 1318, the wireless device predicts the precoder using the linear combination coefficients, the SD basis, the FD basis, and the DD basis, or an optional selected subset. The wireless device may perform prediction according to any of the embodiments and examples described herein.

[0167] In some embodiments, at operation 1320, the wireless device predicts a channel quality indicator (CQI) using the predicted precoder.

[0168] At operation 1322, the wireless device reports any one or more of the following to the network node: a predicted precoder, an indication of the SD basis, the FD basis, the DD basis and the corresponding linear combination coefficients, and / or a predicted CQI.

[0169] Can Fig.13 The method 1300 may be modified, added, or omitted. In addition, Fig.13 One or more operations in the method may be performed in parallel or in any suitable order.

[0170] Fig.14 is a flow chart illustrating an example method in a network node according to certain embodiments. In certain embodiments, Fig.14 One or more operations can be performed by Fig. 9 The described network node 300 performs. The network node is operable to configure a wireless device for CSI reporting.

[0171] The method begins at operation 1412, where a network node (e.g., network node 300) sends a measurement configuration for measuring multiple instances of CSI-RS over a time instance span and a configuration for reporting CSI associated with the multiple instances of CSI-RS over the time instance span to a wireless device (e.g., UE 200).

[0172] At operation 1414, the network node receives, from the wireless device, a CSI report associated with multiple instances of CSI-RS over a time instance span. The CSI report includes an indication of an estimate of linear combination coefficients for combining the SD basis, the FD basis, and the DD basis based on measurements of the multiple CSI-RS instances performed by the wireless device.

[0173] In a specific embodiment, the linear combination coefficients are represented by a three-dimensional matrix, where elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

[0174] In certain embodiments, the multiple instances of the CSI-RS are evenly spaced in time. In certain embodiments, the multiple instances of the CSI-RS are unevenly spaced in time, and the Doppler basis vectors are modified to match the measurement instances.

[0175] At operation 1416, the network node predicts the precoder using the linear combination coefficients, the SD basis, the FD basis, and the DD basis. The network node may predict the precoder according to any of the embodiments and examples described herein.

[0176] In certain embodiments, at operation 1418, the network node predicts a channel quality indicator (CQI) using the predicted precoder.

[0177] Can Fig.14 The method 1400 may be modified, added, or omitted. In addition, Fig.14 One or more operations in the method may be performed in parallel or in any suitable order.

[0178] Without departing from the scope of the present invention, the methods disclosed herein may be modified, added or omitted. The methods may include more, less or other operations. In addition, the operations may be performed in any suitable order.

[0179] The foregoing description sets forth many specific details. However, it should be understood that embodiments may be practiced without these specific details. In other cases, well-known circuits, structures, and techniques are not shown in detail to avoid obscuring the understanding of this description. A person of ordinary skill in the art will be able to implement appropriate functionality using the included descriptions without undue experimentation.

[0180] References in the specification to "one embodiment," "an embodiment," "an example embodiment," etc. indicate that the described embodiment may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Furthermore, these phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it should be considered that those skilled in the art may implement such feature, structure, or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0181] Although the present disclosure has been described according to certain embodiments, it will be apparent to those skilled in the art that the embodiments will be altered and arranged. Therefore, the description of the above embodiments does not limit the present disclosure. Other modifications, substitutions, and variations are also possible without departing from the scope of the present disclosure as defined in the following claims.

Claims

1. A method for reporting channel state information (CSI) performed by a wireless device, the method comprising: measuring (1312) a plurality of instances of a CSI reference signal CSI-RS over a span of time instances; estimating (1314) linear combination coefficients based on the measurements of the plurality of CSI-RS instances, the linear combination coefficients being used to combine a spatial domain SD basis, a frequency domain FD basis, and a Doppler domain DD basis; and A precoder is predicted (1318) using the linear combination coefficients, the SD basis, the FD basis, and the DD basis.

2. The method according to claim 1, further comprising: The predicted precoder is reported (1322) to the network node.

3. The method according to any one of claims 1 to 2, further comprising: An indication of the SD basis, the FD basis, the DD basis, and corresponding linear combination coefficients is reported (1322) to a network node.

4. The method according to any one of claims 1 to 3, further comprising: Using the predicted precoder, predicting (1320) a channel quality indicator CQI; as well as The predicted CQI is reported (1322) to the network node.

5. The method according to any one of claims 1 to 4, further comprising: selecting (1316) a subset of the SD basis, the FD basis, and the DD basis based on a selection criterion, wherein predicting the precoder is based on the selected subset; and The selected subset of the SD basis, the FD basis, and the DD basis is reported (1322) to a network node.

6. The method according to any one of claims 1 to 5, wherein: The linear combination coefficients are represented by a three-dimensional matrix, wherein elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

7. The method according to any one of claims 1 to 6, wherein: The multiple instances of the CSI-RS are evenly spaced in time.

8. The method according to any one of claims 1 to 7, wherein: The multiple instances of the CSI-RS are unevenly spaced in time, and a Doppler basis vector is modified to match the measurement instances.

9. The method according to any one of claims 1 to 8, further comprising: A measurement configuration is received (1308) from a network node for measuring the plurality of instances of the CSI-RS over the span of the time instances.

10. The method according to any one of claims 1 to 9, further comprising: A configuration is received (1310) from a network node for reporting CSI associated with the plurality of instances of the CSI-RS over the span of the time instances.

11. A wireless device (200) capable of reporting channel state information (CSI), the wireless device comprising a processing circuit (202), the processing circuit being operable to: Measuring a plurality of instances of a CSI reference signal CSI-RS over a span of time instances; estimating linear combination coefficients based on the measurements of the plurality of CSI-RS instances, the linear combination coefficients being used to combine a spatial domain SD basis, a frequency domain FD basis, and a Doppler domain DD basis; and A precoder is predicted using the linear combination coefficients, the SD basis, the FD basis, and the DD basis.

12. The wireless device of claim 11, the processing circuit further operable to report the predicted precoder to a network node.

13. The wireless device of any one of claims 11-12, the processing circuit further operable to report an indication of the SD basis, the FD basis, the DD basis, and corresponding linear combination coefficients to a network node.

14. The wireless device of any one of claims 1-3, the processing circuit further operable to: Using the predicted precoder, predicting a channel quality indicator CQI; and Report the predicted CQI to the network node.

15. The wireless device of any one of claims 11-14, the processing circuit further operable to: Based on a selection criterion, a subset of the SD basis, the FD basis, and the DD basis is selected, wherein, predicting the precoder based on the selected subset; and The selected subset of the SD basis, the FD basis, and the DD basis is reported to a network node.

16. The wireless device according to any one of claims 11 to 15, wherein: The linear combination coefficients are represented by a three-dimensional matrix, wherein elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

17. The wireless device according to any one of claims 11 to 16, wherein: The multiple instances of the CSI-RS are evenly spaced in time.

18. The wireless device according to any one of claims 11 to 17, wherein: The multiple instances of the CSI-RS are unevenly spaced in time, and a Doppler basis vector is modified to match the measurement instances.

19. The wireless device of any one of claims 11-18, the processing circuit further operable to receive, from a network node, a measurement configuration for measuring the plurality of instances of the CSI-RS over the span of the time instances.

20. The wireless device of any one of claims 1-9, the processing circuit further operable to receive, from a network node, a configuration for reporting CSI associated with the plurality of instances of the CSI-RS over the time instance span.

21. A method performed by a network node for configuring a wireless device for channel state information (CSI) reporting, the method comprising: sending (1412) to a wireless device a measurement configuration for measuring a plurality of instances of a CSI reference signal CSI-RS over a span of time instances and a configuration for reporting CSI associated with the plurality of instances of the CSI-RS over the span of the time instances, receiving (1414) from the wireless device a CSI report associated with the plurality of instances of the CSI-RS over the span of the time instances, wherein the CSI report comprises an indication of an estimate of linear combination coefficients for combining a spatial domain SD basis, a frequency domain FD basis, and a Doppler domain DD basis based on measurements of the plurality of CSI-RS instances performed by the wireless device; and A precoder is predicted (1416) using the linear combination coefficients, the SD basis, the FD basis, and the DD basis.

22. The method according to claim 21, further comprising: Using the predicted precoder, a channel quality indicator CQI is predicted (1418).

23. The method according to any one of claims 21-22, wherein: The linear combination coefficients are represented by a three-dimensional matrix, wherein elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

24. The method according to any one of claims 21 to 23, wherein: The multiple instances of the CSI-RS are evenly spaced in time.

25. The method according to any one of claims 21 to 23, wherein: The multiple instances of the CSI-RS are unevenly spaced in time, and a Doppler basis vector is modified to match the measurement instances.

26. A network node (300) capable of configuring a wireless device (200) for channel state information (CSI) reporting, the network node comprising a processing circuit (302) operable to: sending to a wireless device a measurement configuration for measuring a plurality of instances of a CSI reference signal CSI-RS over a time instance span and a configuration for reporting CSI associated with the plurality of instances of the CSI-RS over the time instance span, receiving, from the wireless device, CSI reports associated with the plurality of instances of the CSI-RS over the span of the time instances, wherein: The CSI report includes an indication of an estimate of linear combination coefficients for combining a spatial domain SD basis, a frequency domain FD basis, and a Doppler domain DD basis based on measurements of the plurality of CSI-RS instances performed by the wireless device; and A precoder is predicted using the linear combination coefficients, the SD basis, the FD basis, and the DD basis.

27. The network node of claim 26, the processing circuit further operable to predict a channel quality indicator (CQI) using the predicted precoder.

28. The network node according to any one of claims 26-27, wherein: The linear combination coefficients are represented by a three-dimensional matrix, wherein elements of the three-dimensional matrix indicate weights for combining the SD basis, the FD basis, and the DD basis.

29. The network node according to any one of claims 26 to 28, wherein: The multiple instances of the CSI-RS are evenly spaced in time.

30. The network node according to any one of claims 26 to 29, wherein: The multiple instances of the CSI-RS are unevenly spaced in time, and a Doppler basis vector is modified to match the measurement instances.

Images