Uplink control information

Abstract

Embodiments of the present disclosure relate to methods, devices, apparatuses, and computer-readable storage media for designing Uplink Control Information (UCI). The present method comprises, at a terminal device, means for determining a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between a terminal device and a network device—the matrix having spatial components and frequency components—; a step of circularly shifting the frequency components of the matrix such that a target coefficient of the set of non-zero linear combination coefficients is located at a frequency component having a predetermined index of the frequency components in the shifted matrix; a step of generating a first indication indicating a spatial component associated with the target coefficient in the matrix; and a step of transmitting uplink control information comprising the first indication to a network device. In this way, a new solution for designing UCI can reduce the overhead for reporting parameters in “UCI Part 1” and “UCI Part 2”.

Description

Technology Field

[0001] The embodiments of the present disclosure generally relate to the field of telecommunications and, in particular, to methods, devices, apparatuses, and computer-readable storage media for designing Uplink Control Information (UCI). Background Technology

[0002] In 3GPP NR (New Radio) Rel-15 and 16, a compression mechanism was introduced to reduce the overhead of reporting Channel State Information (CSI) from UEs to Base Transceiver Stations (BTS) that is required to operate Multi-User Multiple Input Multiple Output (MU-MIMO) in the downlink. The mechanism consists of two DFT-based operations in the spatial domain and the frequency domain. These operations are applied to each layer for rank indicators (RIs) of 1 to 4. The CSI message may include a Channel Quality Indicator (CQI) and a Precoding Matrix Indicator (PMI). The CQI may be obtained from the estimation of the expected SINR after decoding the codewords multiplexed across the reported spatial layers, and the PMI may include a set of complex value precoding weights required to obtain the corresponding CQI. Both CQI and PMI parameters are reported for each subband. PMI is represented as a matrix containing column vectors equal to the number of subbands for each reported layer. SD and FD compression operations are applied to these PMI matrices across their rows and columns, respectively.

[0003] An important aspect of CSI signaling for MU-MIMO is the arrangement of compressed PMI components within an Uplink Control Information (UCI) message. Conventionally, this message can be organized into two parts: "UCI Part 1" and "UCI Part 2." "UCI Part 1" may contain parameters and CQI information necessary to determine the payload size of "UCI Part 2." "UCI Part 1," transmitted over the Physical Uplink Control Channel (PUCCH), may have a very short, fixed-size payload and may be encoded with a very strong forward error correction code to ensure error-free decoding. "UCI Part 2" contains most of the compressed PMI and may be transmitted over the Physical Uplink Shared Channel (PUSCH), thereby having the same error protection as the data. The problem to be solved

[0004] In general, exemplary embodiments of the present disclosure provide a solution for uplink control information (UCI) design.

[0005] In a first embodiment, a method is provided. The method comprises: means for determining, in a terminal device, a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between a terminal device and a network device, wherein the matrix has spatial components and frequency components; a step of circularly shifting the frequency components of the matrix such that a target coefficient of the set of non-zero linear combination coefficients is located at a frequency component having a predetermined index of the frequency components in the shifted matrix; a step of generating a first indication indicating a spatial component associated with the target coefficient in the matrix; and a step of transmitting uplink control information including the first indication to a network device.

[0006] In a second aspect, a method is provided. The method comprises means for receiving uplink control information including a first indication from a network device and from a terminal device, wherein the first indication indicates spatial components associated with a target coefficient in a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and the network device, the matrix having spatial components and frequency components; and steps of determining state information of a channel based on the uplink control information.

[0007] In a third embodiment, a device is provided. The device comprises at least one processor; and at least one memory including computer program codes; and the at least one memory and computer program codes are configured to use at least one processor to enable the device to determine, at least at a terminal device, a matrix including a set of non-zero linear combination coefficients for quantizing a channel between a terminal device and a network device, wherein the matrix has spatial components and frequency components; to circularly shift the frequency components of the matrix such that a target coefficient of the set of non-zero linear combination coefficients is located at a frequency component having a predetermined index of the frequency components in the shifted matrix; to generate a first indication indicating a spatial component associated with the target coefficient in the matrix; and to transmit uplink control information including the first indication to a network device.

[0008] In a fourth embodiment, a device is provided. The device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to use at least one processor to enable the device to receive uplink control information including a first indication from at least a network device and from a terminal device, wherein the first indication indicates spatial components associated with a target coefficient in a matrix including a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and the network device, the matrix having spatial components and frequency components; and to determine state information of a channel based on the uplink control information.

[0009] In a fifth embodiment, the apparatus comprises: means for determining a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between a terminal device and a network device, wherein the matrix has spatial components and frequency components; means for circularly shifting the frequency components of the matrix such that a target coefficient of the set of non-zero linear combination coefficients is located at a frequency component having a predetermined index of the frequency components in the shifted matrix; means for generating a first indication indicating a spatial component associated with the target coefficient in the matrix; and means for transmitting uplink control information including the first indication to a network device.

[0010] In a sixth aspect, a device is provided comprising means for receiving uplink control information including a first indication from a network device and from a terminal device, wherein the first indication indicates spatial components associated with a target coefficient in a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and the network device, the matrix having spatial components and frequency components; and means for determining state information of a channel based on the uplink control information.

[0011] In a seventh embodiment, a computer-readable medium is provided that stores a computer program that causes the device to perform a method according to a first embodiment when executed by at least one processor of the device.

[0012] In the eighth embodiment, a computer-readable medium is provided that stores a computer program that causes the device to perform a method according to the second embodiment when executed by at least one processor of the device.

[0013] It should be understood that the description section of the invention is not intended to identify the core or essential features of the embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will be readily apparent from the following description. Brief explanation of the drawing

[0014] Now, some exemplary embodiments will be described with reference to the attached drawings, in which: FIG. 1 illustrates an exemplary communication network in which exemplary embodiments of the present disclosure may be implemented; FIG. 2 illustrates a schematic diagram illustrating a process for UCI design according to exemplary embodiments of the present disclosure; FIGS. 3a and 3b illustrate exemplary matrices and corresponding bitmaps according to some exemplary embodiments of the present disclosure; FIGS. 4a and 4b illustrate exemplary matrices and corresponding bitmaps after shift operations according to some exemplary embodiments of the present disclosure; FIG. 5 illustrates a flowchart of an exemplary method (500) of UCI design according to some exemplary embodiments of the present disclosure; FIG. 6 illustrates a flowchart of an exemplary method (600) of UCI design according to some exemplary embodiments of the present disclosure; FIG. 7 is a simplified block diagram of a device suitable for implementing exemplary embodiments of the present disclosure; FIG. 8 illustrates a block diagram of an exemplary computer-readable medium according to some embodiments of the present disclosure. Throughout the drawings, identical or similar reference numerals represent identical or similar elements. Specific details for implementing the invention

[0015] The principles of the present disclosure will now be described with reference to some exemplary embodiments. It should be understood that these embodiments are described for illustrative purposes only and are intended to help those skilled in the art understand and implement the present disclosure without suggesting any limitations on the scope of the present disclosure. The present disclosure as described herein may be implemented in various ways other than those described below.

[0016] In the following specific details and claims, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains.

[0017] As used herein, the term “communication network” refers to a network that follows any suitable communication standards or protocols, such as LTE (long term evolution), LTE-A (LTE-Advanced), and 5G NR, and employs any suitable communication technology, including, for example, Multiple-Input Multiple-Output (MIMO), OFDM, Time Division Multiplexing (TDM), Frequency Division Multiplexing (FDM), Code Division Multiplexing (CDM), Bluetooth, ZigBee, Machine Type Communication (MTC), eMBB, mMTC, and uRLLC technologies. For the sake of discussion, in some embodiments, an LTE network, an LTE-A network, a 5G NR network, or any combination thereof is taken as an example of a communication network.

[0018] As used herein, the term “network device” refers to any suitable device on the network side of a communication network. A network device may include any suitable device on the access network of a communication network, such as a base station (BS), a relay, an access point (AP), a node B (NodeB or NB), an evolved node B (eNodeB or eNB), a 5G or next-generation node B (gNB), a remote radio module (RRU), a radio header (RH), a remote radio head (RRH), a low-power node such as a femto, pico, etc. For the sake of discussion, in some embodiments, a gNB is taken as an example of a network device.

[0019] Network devices may also include any suitable devices in the core network, such as, for example, Multi-Standard Radio (MSR) equipment, such as MSR BSs; network controllers, such as Radio Network Controllers (RNCs) or Base Station Controllers (BSCs) and Multi-cell / multicast Coordination Entities (MCEs); Mobile Switching Centers (MSCs) and MMEs; Operation and Management (O&M) nodes; Operation Support System (OSS) nodes; Self-Organization Network (SON) nodes; location nodes, such as Enhanced Serving Mobile Location Centers (E-SMLCs); and / or Mobile Data Terminals (MDTs).

[0020] As used herein, the term “terminal device” refers to a device capable of communicating with a network device or additional terminal devices in a communication network and / or configured to do so, arranged to do so, or operable to do so. Communication may involve transmitting and / or receiving wireless signals using electromagnetic signals, radio waves, infrared signals, and / or other types of signals suitable for transmitting information over air. In some embodiments, the terminal device may be configured to transmit and / or receive information without direct human interaction. For example, the terminal device may transmit information to the network device according to predetermined schedules when triggered by internal or external events, or in response to requests from the network side.

[0021] Examples of terminal devices include, but are not limited to, user equipment (UE), such as smartphones, wireless-enabled tablet computers, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), and / or wireless customer-premises equipment (CPE). For the sake of discussion, some embodiments below will be described with reference to UEs as examples of terminal devices, and the terms “terminal device” and “user equipment (UE)” may be used interchangeably in connection with the present disclosure.

[0022] As used herein, the term "location server" may refer to a service function that provides the positioning of a target UE to a location client. The location server may communicate with the target UE to obtain a positioning measurement report from the target UE via upper-layer signaling. The location service may also communicate with a network device to obtain information associated with the positioning of the target UE. The location server may be a component independent of the network device. Optionally, the location server may be any function module or function entity embedded in the network device.

[0023] Corresponding to the term "location server," the term "location client" as used herein may refer to an application or entity requesting the location of a target UE. The location client may send a location request to a location service and receive the positioning of the target UE from the location server. Additionally, the location client may be considered as the target UE itself.

[0024] As used herein, the term "cell" refers to an area covered by radio signals transmitted by a network device. A terminal device within the cell is serviced by the network device and can access a communication network through the network device.

[0025] As used in this specification, the term "circuit section" may refer to one or more or all of the following:

[0026] (a) Examples of hardware-only circuit implementations (e.g., examples of implementations as only analog and / or digital circuits) and

[0027] (b) combinations of hardware circuits and software, e.g. (where applicable): (i) combinations of software / firmware and analog and / or digital hardware circuit(s) and (ii) any parts of hardware processor(s) and software (including digital signal processor(s), software, and memory(s)) that work together to enable a device, e.g., a mobile phone or server, to perform various functions and

[0028] (c) Hardware circuit(s) and / or processor(s) that require software (e.g., firmware) for operation, but where software may not exist when not required for operation, such as microprocessors(s) or a part of microprocessors(s).

[0029] The definition of circuit part applies to all uses of this term in this application. As an additional example, as used in this application, the term circuit part also covers only a hardware circuit or processor (or a number of processors) or an implementation of a hardware circuit or processor and a part of its (or their) accompanying software and / or firmware. The term circuit part also covers, for example and where applicable to certain claim elements, baseband integrated circuits or processor integrated circuits for mobile devices or similar integrated circuits in servers, cellular network devices, or other computing or network devices.

[0030] As used herein, singular forms are intended to include plural forms unless the context clearly indicates otherwise. The term “includes” and its ending variations should be interpreted as open-ended terms meaning “includes but not limited thereto.” The term “based on” should be interpreted as “based at least partially on”. The terms “one embodiment” and “embodiment” should be interpreted as “at least one embodiment”. The term “another embodiment” should be interpreted as “at least one other embodiment”. Other explicit and implicit definitions may be included below.

[0031] As described above, the Precoding Matrix Indicator (PMI) is represented as a matrix containing column vectors equal to the number of subbands for each reported layer. SD and FD compression operations are applied to these PMI matrices across their rows and columns, respectively. Consequently, the PMI for a layer is compressed into three component parts: an orthogonal basis set of DFT vectors for SD compression, an orthogonal basis set of DFT vectors for FD compression, and a set of complex linear combination (LC) coefficients. Accordingly, both compression operations are linear projections onto the two orthogonal bases. When the two orthogonal bases are reported by representing a subset from a DFT-based codebook, the LC coefficients are quantized in amplitude and phase using scalar quantizers. Since only a subset of non-zero LC coefficients can be reported per layer to reduce overhead, it is required that both the locations of the reported non-zero coefficients and their complex values ​​be reported. A bitmap for each layer is used to report these locations.

[0032] Each PMI vector can be reported to the BTS based on a complex (amplitude and phase) scaling factor, as this factor does not affect the precorder design. This property is used, for example, to apply appropriate phase shifts to the columns of the PMI matrix before FD compression to optimize the compression operation. This property also enables applying common scaling to all LC coefficients before quantization such that the upper limit of the amplitude is 1 and the quantization interval for the amplitude is [0,1].

[0033] This common scaling of LC coefficients is applied independently to the coefficients of each layer and, for that layer, consists of the amplitude and phase of the "strongest" coefficient, i.e., the coefficient with the largest magnitude. Since the strongest coefficient after normalization can be equal to 1, it is not required that the amplitude or phase of the strongest coefficient be reported. Instead, its position in the bitmap is signaled by the strongest coefficient indicator (SCI).

[0034] An important aspect of Channel State Information (CSI) signaling for Multi-User Multiple Input Multiple Output (MU-MIMO) in Uplink Control Information (UCI) messages is the arrangement of components of the compressed PMI. In a conventional manner, this message can be organized into two parts: "UCI Part 1" and "UCI Part 2." "UCI Part 1" may contain parameters necessary to determine the payload size of "UCI Part 2" and CQI information. "UCI Part 1," transmitted over the Physical Uplink Control Channel (PUCCH), may have a very short and fixed-size payload and may be encoded with a very strong forward error correction code to ensure error-free decoding. "UCI Part 2" contains most of the compressed PMI and may be transmitted over the Physical Uplink Shared Channel (PUSCH), thereby having the same error protection as the data.

[0035] The information in "UCCI Part 1" used to determine the payload size of "UCI Part 2" can be arranged in two ways: (1) the number of non-zero LC coefficients for each layer (the number of layers is equal to the maximum reported rank) and (2) the total number of non-zero LC coefficients for all reported layers and RI indicators. Both ways make it possible to determine the reported rank and the number of bitmaps in "UCI Part 2" accordingly. The number of quantized coefficients in "UCI Part 2" from which the payload size can be determined is also reported.

[0036] Note that some parameters required for determining the size of "UCI Part 2" and for accurate PMI decoding are not reported in "UCI Part 1" because they are configured by the network. These are the parameters that control the maximum overhead for CSI reporting, namely the size of SD and FD contributions and the maximum number of non-zero factors.

[0037] Method (2) is desirable because, as described above, the overhead for displaying the number of non-zero LC coefficients in "UCI Part 1" can be significantly reduced. However, Method (2) has the disadvantage of making the signaling of SCI more inefficient. In fact, since the normalization of LC coefficients is performed independently for each layer, there is one SCI for each layer reported in Part 2. Unless a constraint is introduced on the number of non-zero coefficients for each layer, the SCI Bits must include (which is the total number of non-zero coefficients).

[0038] Introducing such constraints is undesirable because the UE must select the LC coefficients to be reported to jointly optimize compression across the layers reported for a given maximum budget of coefficients. For example, adding unnecessary constraints to this optimization by limiting the number of coefficients allowed to be reported per layer can have a negative impact on performance.

[0039] Accordingly, the present disclosure proposes a signaling mechanism for SCIs and FD contributions that reduces the overhead of UCI messages by utilizing the properties of DFT-based frequency compression—namely, that any phase ramp applied across the columns of the LC coefficient matrix prior to FD compression is evident to the BTS and does not require signaling.

[0040] Embodiments of the present disclosure provide solutions for UCI design to solve the above-mentioned and other potential problems at least partially. Some exemplary embodiments of the present disclosure will be described below with reference to the drawings. However, those skilled in the art will readily understand that as the present disclosure extends beyond these limited embodiments, the detailed description given herein regarding these drawings is for illustrative purposes only.

[0041] FIG. 1 illustrates an exemplary communication network (100) in which embodiments of the present disclosure may be implemented. The communication network (100) comprises network devices (110) and terminal devices (120-1, 120-2 ... and 120-N)—which may be collectively or individually referred to as “terminal device(s)” (120). The network (100) may provide one or more cells (102) for serving the terminal devices (120). The number of network devices, terminal devices, and / or cells should be understood as being given for illustrative purposes without presenting any limitation to the present disclosure. The communication network (100) may include any suitable number of network devices, terminal devices, and / or cells configured to implement embodiments of the present disclosure.

[0042] In a communication network (100), a network device (110) can transmit data and control information to a terminal device (120), and the terminal device (120) can also transmit data or control information to the network device (110). The link from the network device (110) to the terminal device (120) is referred to as a downlink (DL), while the link from the terminal device (120) to the network device (110) is referred to as an uplink (UL).

[0043] Communication in the network (100) may follow any suitable standard, including but not limited to mobile communication global system (GSM), Long Term Evolution (LTE), LTE-Evolution, LTE-Advanced (LTE-A), broadband code division multiple access (WCDMA), code division multiple access (CDMA), GSM EDGE radio access network (GERAN), etc. In addition, communications may be performed according to any generation communication protocols currently known or to be developed in the future. Examples of communication protocols include but not limited to 1st generation (1G), 2nd generation (2G), 2.5G, 2.75G, 3rd generation (3G), 4th generation (4G), 4.5G, and 5th generation (5G) communication protocols.

[0044] To obtain the CSI of a communication channel between a network device (110) and a terminal device (120), the network device (110) may transmit a Channel State Information-reference signal (CSI-RS) to the terminal device (120). The terminal device (120) may receive the CSI-RS from the network device (110) and obtain channel information by measuring the CSI-RS. Subsequently, the terminal device (120) may determine the CSI of the communication channel based on the obtained channel information and a corresponding codebook. For example, the obtained channel information may be quantized into a CSI based on a corresponding codebook. The terminal device (120) may report the CSI to the network device (110). The process for reporting the CSI is also called "CSI feedback." The CSI can ensure the reliability of wireless communication between the network device (110) and the terminal device (120). As described above, for CSI signaling, an important aspect is the arrangement of compressed PMI components in the uplink control information (UCI) message.

[0045] FIG. 2 illustrates a schematic diagram of a process (200) for designing a UCI according to exemplary embodiments of the present disclosure. For the sake of discussion, the process (200) will be described with reference to FIG. 1. The process (200) may involve terminal devices (120) and network devices (110) as illustrated in FIG. 1.

[0046] As illustrated in FIG. 2, the terminal device (120) determines a matrix (210) that characterizes the channel between the terminal device (120) and the network device (110). The matrix may have spatial components and frequency components and corresponds to a bitmap representing a set of non-zero linear combination coefficients for quantizing the channel.

[0047] In some exemplary embodiments, the terminal device (120) may receive downlink control information received from the network device (110) and obtain a resource indication associated with spatial components and frequency components—which is known to both the terminal device and the network device. The terminal device (120) may determine a matrix based on the downlink control information and the resource indication.

[0048] Such a matrix and a corresponding bitmap may be illustrated in FIG. 3a and FIG. 3b, respectively. As illustrated in FIG. 3a, the matrix has spatial components in the spatial domain (310) and frequency components in the frequency domain (320). Such a matrix illustrated in FIG. 3a may be referred to as an LC coefficient matrix.

[0049] As described above, the matrix can be obtained by applying compression to a PMI matrix representing a set of precoding vectors for a given spatial layer for all configured subbands that can be displayed in downlink control information received from a network device (110). Size PMI matrix Given this, here is the number of antenna ports for each polarization in a transmitting two-dimensional cross-polarized antenna array, and is the number of constructed PMI subbands. For rank indicators (RI) greater than 1, there is one such PMI matrix for each RI spatial layer. The compression operations for the PMI matrix W are linear and can be expressed by the following equation:

[0050]

[0051] Here, the matrix The column vectors of are of magnitude These are the components of the SD orthogonal basis, The columns are of size It forms the FD orthogonal basis, is the complex value LC coefficients It is a matrix. Matrix may refer to the matrix illustrated in Fig. 3a. To further reduce signaling overhead, Only a subset of the LC coefficients is reported, and the remaining coefficients are set to zero. This group of reported LC coefficients is referred to as non-zero (NZ) coefficients. The NZ coefficients may refer to cells in FIG. 3a that are not equal to zero, for example, cell (331).

[0052] Accordingly, PMI reporting for the hierarchy includes two indicators for SD and FD-based subset selection, respectively, and In the matrix Indicating the locations of non-zero coefficients It can be made of bitmaps. A bitmap corresponding to a matrix can be illustrated in FIG. 3b. As illustrated in FIG. 3a and FIG. 3b, the rows and columns of the bitmap can correspond to spatial components and frequency components, for example, the 0th frequency component in the frequency domain (320) corresponds to the 0th column of the bitmap.

[0053] In matrices There exists a target coefficient among the non-zero coefficients. The target coefficient may be referred to as the maximum coefficient of the non-zero coefficients, i.e., the strongest coefficient. To reduce the overhead of reporting the indication for the strongest coefficient, the terminal device (120) determines a shift operation for the frequency components of the matrix such that the strongest coefficient is located at a frequency component having a predetermined index.

[0054] In some exemplary embodiments, the terminal device (120) may determine indices of frequency components and perform a modulo operation on the frequency components in a matrix based on the indices of frequency components, the number of frequency components in a predefined set of frequency components, the predetermined indices, and a reference index of the frequency components. The reference index may represent the frequency components associated with the target coefficient before the shift. The terminal device (120) may perform a shift operation based on the result of the modulo operation.

[0055] for example, If we say that is the number of frequency components, then the indices , and Frequency domain-based size formed by frequency components having is the index of the frequency component with the strongest coefficient. For example, the component Assume that the predefined index value for is 0. The terminal device (120) can perform a shift operation based on the following equation:

[0056]

[0057] Next, the terminal device (120) determines an indication of the strongest coefficient, i.e., SCI, based on the spatial components where the strongest coefficient is located. SCI can indicate the spatial components associated with the target coefficient in the matrix.

[0058] The terminal device (120) also generates another indication for indicating a frequency range associated with a subset of frequency components based on a predetermined index and frequency components. That is, the subset of frequency components excludes the frequency component having the predetermined index.

[0059] In some exemplary embodiments, the terminal device (120) may determine from the frequency components a target frequency component associated with a predetermined index and select from the frequency components a subset of frequency components excluding the target frequency component. The terminal device (120) may determine the indices of the subset of frequency components and generate a display for indicating a frequency range based on the indices of the subset of frequency components.

[0060] Referring again to the assumptions related to Equation (2), the terminal device (120) has no "0th" frequency component as follows, size A subset of the frequency components of can be reported:

[0061]

[0062] After determining the indications associated with the SCI and frequency range, the terminal device (120) can transmit uplink control information including both indications to the network device (110) (220).

[0063] It should be understood that the UCI may include other messages necessary to report relevant parameters for estimating the channel state.

[0064] In some exemplary embodiments, the UCI may also include a bitmap corresponding to a matrix of LC coefficients. The bitmap may be determined based on the matrix before the shift operation. As described above, this bitmap may indicate the positions of the NZ coefficients in the matrix. After the matrix shift operation, the bitmap may also be updated based on a predetermined index.

[0065] In some exemplary embodiments, the terminal device (120) can determine a corresponding relationship between each index of the indices

[0066] In some exemplary embodiments, the terminal device (120) transmits uplink control information that also includes an updated bitmap.

[0067] Referring to FIGS. 3a and 3b and FIGS. 4a and 4b, shift operations are clearly illustrated. As described above, the matrix of FIG. 3a may have a size of 2L*M, and a set of NZ coefficients exists in the matrix, FIG. 3b illustrates a bitmap corresponding to the matrix of FIG. 3a. As illustrated in FIG. 3a, it is assumed that the strongest coefficient (330) is located at the first frequency component (341). For example, the terminal device (120) may shift the matrix so that the strongest coefficient is located at the 0th frequency component. The shifted matrix may be illustrated in FIG. 4a. The strongest coefficient (330) is located at the 0th frequency component (340). Correspondingly, the bitmap illustrated in FIG. 3b may be updated to become the bitmap illustrated in FIG. 4b.

[0068] Without loss of generality, assuming the row-direction read order of the bitmap in FIG. 4a, the strongest coefficient is the third NZ coefficient, and thus, without the proposal of the present disclosure, this is bits: Bits: Will be indicated as SCI=2 or 0010 (4-bit binary representation of 2). Value for this layer It must also be reported in "UCI Part 1".

[0069] According to the solution of the present disclosure, if a predetermined index is "0th," in the example of FIG. 3a, the terminal device (120) can apply a shift operation to one position to the left to the frequency components. For example, the frequency components and the index of the FD component with the strongest coefficient is Assume that it is given as follows. After circular shift and reordering, the FD-based subset is It is given as. On the other hand, SCI is Bits - in this example, this is: SCI=1 or 001 (3-bit binary representation of 1) - are indicated to report the SD component index.

[0070] Referring again to FIG. 2, the network device (110) receives uplink control information from the terminal device (120) and determines the state information of the channel based on the uplink control information.

[0071] In some exemplary embodiments, the network device (110) may determine a matrix based on uplink control information and determine state information based on the matrix. As described above, the matrix may be obtained by applying compression to the PMI matrix. The network device (110) needs to reconstruct the PMI matrix based on the matrix. According to the UCI, the network device (110) may determine a subset of frequency components excluding the target frequency component, and the network device (110) may reconstruct the PMI by adding the target frequency component to the subset of frequency components.

[0072] In this way, a new solution for designing UCI can reduce the overhead of reporting parameters in "UCI Part 1" and "UCI Part 2".

[0073] In the following, the principle of circular shifting will be explained. As described above, any circular shift applied to frequency components is equivalent to the multiplication of columns of PMI by phase ramp before applying frequency compression. Since this phase ramp operation performed at the terminal device (120) is obvious in the precoder design, it does not need to be reported to the network device (110).

[0074] Precoding matrix It is well known that phase rotation across the columns does not affect the performance of the precorder, and thus the network device (110) does not affect performance and the phase adjustment per column as much as It can be reconstructed. This applies to the design of any type of precorder. The matrix before frequency domain compression. It will be suggested that phase adjustments applied across the columns do not need to be reported to the network device (110). Additionally, it will be noted that the selection of these phases is an important degree of freedom that the terminal device (120) can utilize to improve frequency compression, that is, to reduce reconstruction errors in the network device (110).

[0075] First, without selecting a basis subset, i.e. Assuming, all Consider an ideal case for frequency compression with the reporting of dequantized frequency domain coefficients. Note that this is merely a hypothetical case because there is no actual compression gain in the frequency domain. Before the terminal device (120) performs DFT processing across subbands Assuming that phase adjustments are applied to the columns of, the diagonal matrix of arbitrary phase rotations Displays as:

[0076]

[0077] A network device (110) If you know, precorder is reconstructed as follows:

[0078]

[0079] On the other hand, the network device (110) If you do not know, reconstruction produces the following:

[0080]

[0081] In this ideal case, 1) the difference between reconstruction (5) and (6) is only the phase rotation across the columns of the precorder, i.e.

[0082]

[0083] And, 2) Linear combination matrix Assuming a perfect report of (4), it was found that applying phase rotation to (4) is irrelevant.

[0084] Consider the realistic case of basis subset selection and quantization of linear combination coefficients. FD coefficients known in the network device (110) It is called a matrix. The maximum of just Note that only the coefficients are non-zero. Quantization error also affects the non-zero coefficients. Introducing an error matrix between the real and ideal matrices of linear combination coefficients yields the following:

[0085]

[0086] In a very general case, it can be expressed as follows:

[0087]

[0088] If the network device (110) knows the phase shift R, the precoder W' is reconfigured to have an error as follows:

[0089]

[0090] A network device (110) If you do not know, precorder reconstruction produces the following:

[0091]

[0092] By comparing (10) and (11), this will have the following:

[0093]

[0094] in other words, The difference between the two reconstructions with and without reporting is the phase rotation applied to the precorder's columns, which does not affect the precorder's performance. However, unlike the ideal case, applying appropriate phase rotation to the terminal device makes a difference in terms of reconstruction error. In practice, even if the network device is unaware of these phase adjustments, the terminal device [reduces] the reconstruction error Phase rotations such that they are minimized according to some metric The selection of can be optimized.

[0095] Both results (7) and (12) are go not It is maintained when, and The expressions about Note that it becomes more complex because it is no longer an identity matrix.

[0096] In conclusion, when applying frequency domain compression, phase adjustments Optimization of can be used by terminal devices to improve PMI accuracy. However, these adjustments do not need to be transmitted to network devices to achieve this gain.

[0097] Note that various operations can be expressed by these phase rotations. The oversampled DFT codebook is the union of versions of the critically sampled codebook shifted to the original form. It can be described as, where the minimum shift is a fraction. Accordingly, by using notation (3), the size of It is possible to express the selection of one of the orthogonal groups, This is given by the phase ramp:

[0098]

[0099] and Similarly, The circular shift of frequency domain candidate components in the original domain, By applying a phase ramp across the columns (the minimum shift multiplier is ) can be obtained. For example, index A circular shift that moves the FD component of to position '0' can be expressed as (4), and This is given by the phase ramp:

[0100]

[0101] and Finally, oversampling and cyclic shifts also ensure smooth phase transitions along its rows and avoid 'phase jumps' before applying frequency domain compression. It can be combined with phase adjustments for the columns of. The diagonal matrix of these phase adjustments is as follows: If written as:

[0102]

[0103] is is. In general, terminal devices are as described in (4), A combination of these three operations (oversampling, cyclic shifts, and phase adjustments) can be applied by performing a set of phase rotations on the columns of, and the rotation matrix is ​​given as follows:

[0104]

[0105] More detailed information about exemplary embodiments according to the present disclosure will be explained with reference to FIGS. 5 and 6.

[0106] FIG. 5 illustrates a flowchart of an exemplary method (500) for designing a UCI according to some exemplary embodiments of the present disclosure. The method (500) may be implemented in a terminal device (120) as illustrated in FIG. 1. For the sake of discussion, the method (500) will be described with reference to FIG. 1.

[0107] In 510, the terminal device (110) determines a matrix containing a set of non-zero linear combination coefficients for quantizing the channel between the terminal device and the network device—the matrix has spatial components and frequency components.

[0108] In some exemplary embodiments, the terminal device (110) may receive downlink control information received from a network device and obtain resource indications associated with spatial components and frequency components. The terminal device (110) may also determine a matrix based on the downlink control information and resource indications.

[0109] In 520, the terminal device (110) circularly shifts the frequency components of the matrix such that the target coefficient of the set of non-zero linear combination coefficients is located at the frequency component having a predetermined index of the frequency components in the shifted matrix.

[0110] In some exemplary embodiments, the terminal device (110) may determine indices of frequency components. The terminal device (110) may also determine a reference index from the indices of frequency components—the reference index indicates a frequency component associated with a target coefficient in a matrix—and shift the frequency components based on the indices of frequency components, the predetermined index, and the reference index.

[0111] In 530, the terminal device (110) generates a first indication that displays a spatial component associated with a target coefficient in a matrix.

[0112] In some exemplary embodiments, the terminal device (110) can determine a maximum coefficient from a set of non-zero linear combination coefficients as a target coefficient and generate a first indication based on the index of a spatial component associated with the target coefficient in a matrix.

[0113] In 540, the terminal device (110) transmits uplink control information including a first indication to the network device (120).

[0114] In some exemplary embodiments, the terminal device (110) determines a bitmap indicating the positions of non-zero linear combination coefficients in the shifted matrix based on the shifted matrix; and can transmit uplink control information including the bitmap.

[0115] In some exemplary embodiments, the terminal device (110) may generate a second indication indicating a frequency range associated with a subset of frequency components based on a predetermined index and frequency components, and transmit uplink control information including the second indication.

[0116] In some exemplary embodiments, the terminal device (110) may determine from the frequency components a target frequency component associated with a predetermined index and select from the frequency components a subset of frequency components excluding the target frequency component. The terminal device (110) may also determine the indices of the subset of frequency components after the shift and generate a second indication based on the indices of the subset of frequency components.

[0117] FIG. 6 illustrates a flowchart of an exemplary method (600) for designing a UCI according to some exemplary embodiments of the present disclosure. The method (600) may be implemented in a network device (110) as illustrated in FIG. 1. For the sake of discussion, the method (600) will be described with reference to FIG. 1.

[0118] In 610, the network device (110) receives uplink control information from the network device and from the terminal device (120), including a first indication—the first indication indicates spatial components associated with target coefficients in a matrix containing a set of non-zero linear combination coefficients for quantizing the channel between the terminal device and the network device, and the matrix has spatial components and frequency components.

[0119] In 620, the network device (110) determines the state information of the channel based on uplink control information.

[0120] In some exemplary embodiments, the network device (110) can determine a matrix based on uplink control information and determine state information based on the matrix.

[0121] In some exemplary embodiments, the network device (110) may receive uplink control information including a bitmap indicating the positions of non-zero linear combination coefficients in a shifted matrix obtained by circularly shifting the frequency components of the matrix.

[0122] In some exemplary embodiments, the network device (110) may receive uplink control information including a second indication indicating a frequency range associated with a subset of frequency components.

[0123] In some exemplary embodiments, a device capable of performing the method (500) (e.g., implemented in a terminal device (110)) further comprises means for performing each step of the method (500). The means may be implemented in any suitable form. For example, the means may be implemented as a circuit or a software module.

[0124] In some exemplary embodiments, the device comprises: means for determining a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between a terminal device and a network device, wherein the matrix has spatial components and frequency components; means for circularly shifting the frequency components of the matrix such that a target coefficient of the set of non-zero linear combination coefficients is located at a frequency component having a predetermined index of the frequency components in the shifted matrix; means for generating a first indication indicating a spatial component associated with the target coefficient in the matrix; and means for transmitting uplink control information including the first indication to a network device.

[0125] In some exemplary embodiments, a device capable of performing the method (600) (e.g., implemented in a network device (120)) further includes means for performing each step of the method (600). The means may be implemented in any suitable form. For example, the means may be implemented as circuits or software modules.

[0126] In some exemplary embodiments, the device comprises means for receiving uplink control information including a first indication from a network device and from a terminal device, wherein the first indication indicates spatial components associated with a target coefficient in a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and the network device, the matrix having spatial components and frequency components; and means for determining state information of a channel based on the uplink control information.

[0127] FIG. 7 is a simplified block diagram of a device (700) suitable for implementing embodiments of the present disclosure. The device (700) may be provided to implement a communication device, for example, a terminal device (120) and a network device (110) as illustrated in FIG. 1. As illustrated, the device (700) includes one or more processors (710), one or more memories (740) coupled to the processor (710), and one or more transmitters and / or receivers (TX / RX) (740) coupled to the processor (710).

[0128] TX / RX (740) is for bidirectional communication. TX / RX (740) has at least one antenna to enable communication. The communication interface may represent any interface required for communication with other network elements.

[0129] The processor (710) may be any type suitable for a local technology network and, as non-limiting examples, may include one or more of general-purpose computers, special-purpose computers, microprocessors, digital signal processors (DSPs), and processors based on a multi-core processor architecture. The device (700) may have multiple processors, such as application integrated circuit chips that are time-dependent on a clock synchronizing the main processor.

[0130] Memory (720) may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) (724), electrically programmable read-only memory (EPROM), flash memory, hard disk, compact disk (CD), digital video disc (DVD), and other magnetic storage devices and / or optical storage devices. Examples of volatile memories include, but are not limited to, random access memory (RAM) (722) and other volatile memories that do not persist during power-off periods.

[0131] A computer program (730) includes computer-executable instructions executed by a related processor (710). The program (730) may be stored in ROM (1020). The processor (710) may perform any suitable operations and processing by loading the program (730) into RAM (720).

[0132] Embodiments of the present disclosure may be implemented by a program (730) so that the device (700) can perform any of the processes of the present disclosure as discussed with reference to FIGS. 2 through 4. Embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0133] In some embodiments, the program (730) may be tangibly contained in a computer-readable medium that may be contained in the device (700) (e.g., memory (720)) or in other storage devices that may be accessed by the device (700). The device (700) may load the program (730) from the computer-readable medium into RAM (722) for execution. The computer-readable medium may include any type of tangible non-volatile storage device such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. FIG. 8 illustrates an example of a computer-readable medium (800) in the form of a CD or DVD. The computer-readable medium has the program (730) stored therein.

[0134] In general, various embodiments of the present disclosure may be implemented in hardware or special-purpose circuits, software, logic, or any combination thereof. While some aspects may be implemented in hardware, others may be implemented in firmware or software that can be executed by a controller, a microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure may be illustrated and described using block diagrams, flowcharts, or other pictorial representations, it should be understood that such blocks, devices, systems, techniques, or methods described herein are non-limiting examples and may be implemented in hardware, software, firmware, special-purpose circuits or logic, general-purpose hardware or controllers, or other computing devices, or any combination thereof.

[0135] The present disclosure also provides at least one computer program product tangibly stored in a non-transient computer-readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, which are executed on a device or virtual processor on an actual target to perform methods (500 and 600) as described above with reference to any one of FIGS. 2 through 4. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., which perform specific tasks or implement specific abstract data types. The functions of program modules may be combined or divided among program modules as required in various environments. Computer-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located on both local and remote storage media.

[0136] Program code for carrying out the methods of the present disclosure may be written in any combination of one or more programming languages. Such program code may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when such program code is executed by the processor or controller, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0137] In connection with the present disclosure, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus or processor to perform various processes and operations as described above. Examples of carriers include computer-readable media, etc.

[0138] A computer-readable medium may be a computer-readable storage medium. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any suitable combination of the foregoings. More specific examples of a computer-readable storage medium may include one or more portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or electrical connections having any suitable combination thereof.

[0139] Furthermore, although operations are described in a specific order, this should not be understood as requiring that these operations be performed in the specific order described or in a sequential order, or that all described operations be performed, in order to achieve desired results. In certain environments, multitasking and parallel processing may be desirable. Likewise, while the foregoing discussion includes various specific implementation details, these should not be interpreted as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to specific embodiments. Specific features described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented separately in multiple embodiments or in any suitable sub-combination.

[0140] Although the present disclosure has been described in language characteristic of structural features and / or methodological operations, it should be understood that the present disclosure as defined in the appended claims is not necessarily limited to the specific features or operations described above. Rather, the specific features and operations described above are disclosed as exemplary forms embodying the claims.

Claims

Claim 1 A method for signaling uplink control information comprising representations indicating a matrix having 2L x M complex-valued linear combination coefficients that can be arranged into 2L spatial components and M frequency components to quantize a channel between a terminal device and a network device, wherein the matrix is ​​K NZ The method having non-zero linear combination coefficients comprises: determining a bitmap representing the positions of the non-zero linear combination coefficients after the frequency components of the matrix are circularly shifted such that the strongest coefficient of the matrix is ​​located at a frequency component having a predetermined index; and a strongest coefficient indicator representing the index of the spatial component associated with the strongest coefficient of the matrix. A method comprising: a step of generating bits; and a step of transmitting uplink control information to a network device, the uplink control information including the strongest coefficient indicator, a bitmap representing the locations of the non-zero linear combination coefficients, and the values ​​of the non-zero linear combination coefficients, wherein the transmitted values ​​of the non-zero linear combination coefficients exclude the strongest coefficient. Claim 2 The method of claim 1 comprises the steps of: receiving downlink control information from the network device; obtaining a resource representation associated with the spatial components and the frequency components; and determining the matrix based on the downlink control information and the resource representation. Claim 3 A method according to claim 1, comprising the steps of: determining indices of the frequency components; determining a reference index from the indices of the frequency components — the reference index represents the frequency component associated with the strongest coefficient in the matrix —; and shifting the frequency components by shifting the frequency components based on the indices of the frequency components, the predetermined index, and the reference index. Claim 4 A method comprising the steps of: receiving uplink control information transmitted from a terminal device in a network device using a method according to any one of claims 1 to 3; and determining state information of the channel based on the uplink control information. Claim 5 A terminal device for signaling uplink control information comprising representations indicating a matrix having linear combination coefficients of 2L x M complex values ​​that can be arranged into 2L spatial components and M frequency components to quantize a channel between a terminal device and a network device, wherein the matrix is ​​K NZ The terminal device has non-zero linear combination coefficients, and comprises: at least one processor; and at least one memory including computer program codes, wherein the at least one memory and the computer program codes utilize the at least one processor to cause the terminal device to determine a bitmap representing the locations of the non-zero linear combination coefficients after the frequency components of the matrix are circularly shifted such that the strongest coefficient of the matrix is ​​located at a frequency component having a predetermined index; and a strongest coefficient indicator representing the index of a spatial component associated with the strongest coefficient of the matrix. A terminal device configured to generate bits; and to transmit uplink control information to the network device, the uplink control information including the strongest coefficient indicator, a bitmap representing the locations of the non-zero linear combination coefficients, and the values ​​of the non-zero linear combination coefficients, wherein the transmitted values ​​of the non-zero linear combination coefficients exclude the strongest coefficient. Claim 6 In paragraph 5, the terminal device comprises: receiving downlink control information from the network device; obtaining a resource representation associated with the spatial components and the frequency components; and determining the matrix based on the downlink control information and the resource representation. Claim 7 In claim 5, the terminal device comprises: determining indices of the frequency components; determining a reference index from the indices of the frequency components — the reference index represents the frequency component associated with the strongest coefficient in the matrix —; and shifting the frequency components by shifting the frequency components based on the indices of the frequency components, the predetermined index and the reference index. Claim 8 A non-transient computer-readable storage medium storing program instructions for enabling a device to perform the method of at least one of claims 1 to 3.

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