Method, apparatus, and medium for signaling uplink control information

Abstract

Embodiments of the present disclosure relate to uplink control information (UCI). Implementations of the present disclosure relate to methods, devices, apparatus, and computer-readable storage media for UCI design. The method includes: determining a matrix at a terminal device, the matrix including a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and a network device, the matrix having a spatial component and a frequency component; cyclically shifting the frequency component of the matrix so that a target coefficient in the set of non-zero linear combination coefficients is located in a frequency component with a predetermined index in the frequency component in the shifted matrix; generating a first indication, the first indication indicating the spatial component associated with the target coefficient in the matrix; and transmitting uplink control information including the first indication to the network device. In this way, the new solution for designing UCI can reduce the overhead for reporting parameters in "UCI Part 1" and "UCI Part 2".

Description

[0001] This application is a divisional application of the invention patent application with international application number PCT / CN2019 / 081612, international application date April 4, 2019, date of entry into the Chinese national phase September 30, 2021, Chinese national application number 201980095125.8, and invention name “Uplink Control Information”. Technical Field

[0002] Embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly to methods, apparatuses, devices, and computer-readable storage media for uplink control information (UCI) design. Background Art

[0003] In 3GPP New Radio (NR) Rel-15 and 16, a compression mechanism was introduced to reduce the overhead of reporting channel state information (CSI) from the UE to the base transceiver station (BTS), which 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 (RI) from 1 to 4. The CSI message may include a channel quality indicator (CQI) and a precoding matrix indicator (PMI). The CQI can be obtained from an estimate of the expected SINR after decoding the codewords multiplexed across the reported spatial layers, and the PMI may include a set of complex-valued precoding weights required to achieve the CQI. Both CQI and PMI parameters are reported for each subband. The PMI is represented by a matrix for each reported layer, each matrix containing as many column vectors as the number of subbands. The SD and FD compression operations are applied to these PMI matrices across their rows and columns, respectively.

[0004] An important aspect of CSI signaling for MU-MIMO is the arrangement of the components of the compressed PMI in the uplink control information (UCI) message. In a conventional manner, the message may be organized into two parts, "UCI Part 1" and "UCI Part 2". "UCI Part 1" may include CQI information, as well as parameters required to determine the payload size of "UCI Part 2". "UCI Part 1", transmitted in the Physical Uplink Control Channel (PUCCH), may have a very short and fixed-size payload and may be encoded using a very strong forward error correction code to ensure error-free decoding. "UCI Part 2" may include a large amount of compressed PMI and be transmitted in the Physical Uplink Shared Channel (PUSCH), so it has the same error protection as the data. Summary of the Invention

[0005] In general, example embodiments of the present disclosure provide a solution for uplink control information (UCI) design.

[0006] In a first aspect, a method is provided. The method includes: determining, at a terminal device, a matrix including a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and a network device, the matrix having a spatial component and a frequency component; cyclically shifting the frequency component of the matrix so that a target coefficient in the set of non-zero linear combination coefficients is located in a frequency component with a predetermined index among the frequency components in the shifted matrix; generating a first indication indicating the spatial component in the matrix associated with the target coefficient; and transmitting uplink control information including the first indication to the network device.

[0007] In a second aspect, a method is provided. The method comprises: receiving, at a network device and from a terminal device, uplink control information including a first indication, the first indication indicating a spatial component 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 the spatial component and a frequency component; and determining state information of the channel based on the uplink control information.

[0008] In a third aspect, a device is provided. The device includes: at least one processor; and at least one memory, the at least one memory including computer program code; the at least one memory and the computer program code being configured to cause the device, through the at least one processor, to at least: determine a matrix at a terminal device, the matrix including a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and a network device, the matrix having spatial components and frequency components; cyclically shift the frequency components of the matrix so that a target coefficient in the set of non-zero linear combination coefficients is located in a frequency component with a predetermined index among the frequency components in the shifted matrix; generate a first indication indicating the spatial component in the matrix associated with the target coefficient; and transmit uplink control information including the first indication to the network device.

[0009] In a fourth aspect, a device is provided. The device includes: at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code are configured to cause the device, through the at least one processor, to at least: receive, at a network device and from a terminal device, uplink control information including a first indication, the first indication indicating a spatial component 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 the spatial component and a frequency component; and determine state information of the channel based on the uplink control information.

[0010] In a fifth aspect, a device is provided, comprising: a component for determining a matrix at a terminal device, the matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and a network device, the matrix having a spatial component and a frequency component; a component for cyclically shifting the frequency components of the matrix so that a target coefficient in the set of non-zero linear combination coefficients is located in a frequency component with a predetermined index among the frequency components in the shifted matrix; a component for generating a first indication, the first indication indicating the spatial component in the matrix associated with the target coefficient; and a component for transmitting uplink control information including the first indication to the network device.

[0011] In a sixth aspect, a device is provided, comprising: a component for receiving, at a network device and from a terminal device, uplink control information comprising a first indication, wherein the first indication comprises a spatial component associated with a target coefficient in a matrix of a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and the network device, the matrix having the spatial component and a frequency component; and a component for determining state information of the channel based on the uplink control information.

[0012] In a seventh aspect, there is provided a computer readable medium having stored thereon a computer program which, when executed by at least one processor of an apparatus, causes the apparatus to perform the method according to the first aspect.

[0013] In an eighth aspect, there is provided a computer readable medium having stored thereon a computer program which, when executed by at least one processor of an apparatus, causes the apparatus to perform the method according to the second aspect.

[0014] It will be understood that the summary of the invention is neither intended to identify key or essential features of the embodiments of the present disclosure nor to limit the scope of the present disclosure. Other features of the present disclosure will become readily apparent through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Some example embodiments will now be described with reference to the accompanying drawings, in which:

[0016] Figure 1 shows an example communication network in which example embodiments of the present disclosure may be implemented;

[0017] Figure 2 shows a schematic diagram illustrating a process for UCI design according to an example embodiment of the present disclosure;

[0018] Figure 3A and Figure 3B A diagram showing an example matrix and corresponding bitmap according to some example embodiments of the present disclosure;

[0019] Figure 4A and Figure 4B A diagram showing an example matrix and corresponding bitmap after a shift operation according to some example embodiments of the present disclosure;

[0020] Figure 5 A flowchart illustrating an example method 500 for UCI design according to some example embodiments of the present disclosure is shown;

[0021] Figure 6 A flowchart illustrating an example method 600 of UCI design according to some example embodiments of the present disclosure is shown;

[0022] Figure 7 is a simplified block diagram of an apparatus suitable for implementing an example embodiment of the present disclosure; and

[0023] Figure 8 A block diagram of an example computer-readable medium is shown, according to some embodiments of the present disclosure.

[0024] Throughout the drawings, the same or similar reference numbers refer to the same or similar elements. DETAILED DESCRIPTION

[0025] The principle of the present disclosure will now be described with reference to some example embodiments. It will be understood that these embodiments are described only for illustrative purposes and to help those skilled in the art understand and implement the present disclosure without implying any limitation on the scope of the present disclosure. The disclosure described herein can be implemented in a variety of ways except for the manner described below.

[0026] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0027] As used herein, the term "communication network" refers to a network that complies with any suitable communication standard or protocol (such as Long Term Evolution (LTE), LTE-Advanced (LTE-A), 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 purposes of discussion, in some example embodiments, an LTE network, an LTE-A network, a 5G NR network, or any combination thereof is considered an example of a communication network.

[0028] 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 in an access network of a communication network, including, for example, a base station (BS), a relay, an access point (AP), a NodeB (NodeB or NB), an evolved NodeB (eNodeB or eNB), a 5G or next-generation NodeB (gNB), a remote radio unit (RRU), a radio head (RH), a remote radio head (RRH), a low-power node (such as a femto node, a pico node, etc.). For the purposes of discussion, in some example embodiments, a gNB is considered as an example of a network device.

[0029] The network device may also include any suitable device in the core network, for example, including multi-standard radio (MSR) radio equipment (such as MSR BS), network controllers (such as radio network controllers (RNC) or base station controllers (BSC)), multi-cell / multicast coordination entities (MCEs), mobile switching centers (MSCs) and MMEs, operations and management (O&M) nodes, operations support system (OSS) nodes, self-organizing network (SON) nodes, positioning nodes (such as enhanced serving mobile positioning center (E-SMLC)) and / or mobile data terminals (MDTs).

[0030] As used herein, the term "terminal device" refers to a device capable of, configured for, arranged for, and / or operable to communicate with a network device or other terminal devices in a communications network. 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 the air. In some example embodiments, a terminal device may be configured to transmit and / or receive information without direct human interaction. For example, a terminal device may transmit information to a network device according to a predetermined schedule, when triggered by an internal or external event, or in response to a request from the network side.

[0031] Examples of terminal devices include, but are not limited to, user equipment (UE), such as a smartphone, a wireless-enabled tablet, a laptop embedded device (LEE), a laptop mounted device (LME), and / or wireless customer premises equipment (CPE). For discussion purposes, in the following, some embodiments will be described with reference to UE as an example of a terminal device, and the terms "terminal device" and "user equipment" (UE) may be used interchangeably in the context of this disclosure.

[0032] 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 via higher-layer signaling to obtain a positioning measurement report for the target UE. The location server may also communicate with a network device to obtain information related to the positioning of the target UE. The location server may be a component independent of the network device. Alternatively, the location server may be any functional module or entity embedded in the network device.

[0033] As used herein, the term "location client," corresponding to the term "location server," may refer to an application or entity that requests the location of a target UE. The location client may transmit a location request to a location server and receive the position of the target UE from the location server. Furthermore, the location client may be considered the target UE itself.

[0034] As used herein, the term "cell" refers to an area covered by radio signals transmitted by a network device. Terminal devices within the cell can be served by the network device and access the communication network via the network device.

[0035] As used herein, the term "circuitry" may refer to one or more or all of the following:

[0036] (a) hardware circuitry only implementations (such as implementations of analog and / or digital circuitry only), and

[0037] (b) a combination of hardware circuitry and software, such as (as applicable): (i) a combination of analog and / or digital hardware circuitry and software / firmware, and (ii) any portion of a hardware processor (including a digital signal processor), software and memory with software, which work together to cause a device (such as a mobile phone or server) to perform various functions), and

[0038] (c) Hardware circuits and or processors, such as a microprocessor or portion of a microprocessor, that require software (eg, firmware) to operate, but where the software may not be present when not required for operation.

[0039] This definition of "circuitry" applies to all uses of the term in this application, including in any claims. As another example, as used in this application, the term "circuitry" also covers an implementation of merely hardware circuitry or a processor (or multiple processors) or portions of a hardware circuitry or processor and their (or their) accompanying software and / or firmware. For example, and where applicable to particular claim elements, the term "circuitry" also covers a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing or network device.

[0040] As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term "including" and variations thereof are to be interpreted as open-ended terms meaning "including, but not limited to." The term "based on" is to be interpreted as "based, at least in part, on." The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment." The term "another embodiment" is to be interpreted as "at least one other embodiment." Additional explicit and implicit definitions may be included below.

[0041] As mentioned above, the precoding matrix indicator (PMI) is represented by a matrix for each reported layer, each matrix containing as many column vectors as the number of subbands. SD and FD compression operations are applied to these PMI matrices across their rows and columns, respectively. Therefore, the PMI for a layer is compressed into three components: 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-valued linear combination (LC) coefficients. Therefore, both compression operations are linear projections onto two orthogonal bases. When two orthogonal bases are reported by indicating a subset from a DFT-based codebook, the LC coefficients are quantized in amplitude and phase using a scalar quantizer. Because each layer can only report a subset of non-zero LC coefficients to reduce overhead, it is necessary to report the positions of the reported non-zero coefficients and their complex values. A bitmap for each layer is used to report these positions.

[0042] Each PMI vector can be reported to the BTS based on a composite (amplitude and phase) scaling factor, as this factor does not affect the precoder design. For example, this property is used to apply appropriate phase shifts to the columns of the PMI matrix before FD compression to optimize the compression operation. This property also allows a common scaling to be applied to all LC coefficients before quantization, so that their amplitudes are capped at 1 and the amplitude quantization interval becomes [0,1].

[0043] This common scaling of the LC coefficients is applied independently to the coefficients of each layer and is based on the amplitude and phase of the "strongest" coefficient (i.e., the coefficient with the largest amplitude) of that layer. Since the strongest coefficient after normalization may be equal to 1, the amplitude and phase of the strongest coefficient do not need to be reported. Instead, its position in the bitmap is indicated by the strongest coefficient indicator (SCI).

[0044] An important aspect of channel state information (CSI) signaling for multi-user multiple input multiple output (MU-MIMO) is the arrangement of the components of the compressed PMI in the uplink control information (UCI) message. In a conventional manner, the message may be organized into two parts, namely "UCI part 1" and "UCI part 2". "UCI part 1" may include CQI information, as well as parameters required to determine the payload size of "UCI part 2". "UCI part 1", transmitted in the physical uplink control channel (PUCCH), may have a very short and fixed-size payload and may be encoded using a very strong forward error correction code to ensure error-free decoding. "UCI part 2" may include a large amount of compressed PMI and be transmitted in the physical uplink shared channel (PUSCH), so it has the same error protection as the data.

[0045] The information in "UCI Part 1" used to determine the payload size of "UCI Part 2" can be arranged in two ways, namely, (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 the RI indicator. Both ways allow the reported rank and therefore the number of bitmaps in "UCI Part 2" to be determined. The number of quantized coefficients is also reported in "UCI Part 2", from which the payload size can be determined.

[0046] It should be noted that some parameters required to determine the size of "UCI Part 2" and for correct PMI decoding are not reported in "UCI Part 1" because they are configured by the network. These are parameters that control the maximum overhead for CSI reporting, namely the size of the SD and FD basis and the maximum number of non-zero coefficients.

[0047] As mentioned above, approach (2) is preferred because the overhead for indicating the number of non-zero LC coefficients in "UCI Part 1" can be significantly reduced. However, approach (2) has the disadvantage of making the signaling of the SCI less efficient. In fact, there is one SCI per reported layer in Part 2 because the normalization of the LC coefficients is done independently for each layer. Unless a restriction is introduced on the number of non-zero coefficients per layer, the SCI should contain bits, and N NZ The total number of non-zero coefficients.

[0048] Introducing such a restriction is undesirable because, for a given maximum budget coefficient, the UE should select the LC coefficients to report to optimize compression jointly across the reported layers. Adding unnecessary constraints to this optimization, for example by limiting the number of coefficients allowed to be reported per layer, may negatively impact performance.

[0049] Therefore, the present disclosure proposes a signaling mechanism for SCI and FD basis that reduces the overhead of UCI messages by exploiting the properties of DFT-based frequency compression (i.e., any phase ramps applied across the columns of the LC coefficient matrix before FD compression are transparent to the BTS and do not require signaling).

[0050] Embodiments of the present disclosure provide a solution for UCI design to at least partially address the above and other potential issues. Some example embodiments of the present disclosure will be described below with reference to the accompanying drawings. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these drawings is for explanatory purposes, as the present disclosure extends beyond these limited embodiments.

[0051] Figure 1 An example communication network 100 is shown in which implementations of the present disclosure may be implemented. The communication network 100 includes a network device 110 and terminal devices 120-1, 120-2, ..., and 120-N, which may be collectively or individually referred to as "terminal devices" 120. The network 100 may provide one or more serving cells 102 to serve the terminal devices 120. It will be understood that the number of network devices, terminal devices, and / or cells provided is for illustrative purposes only and does not imply any limitation of the present disclosure. The communication network 100 may include any suitable number of network devices, terminal devices, and / or cells suitable for implementing implementations of the present disclosure.

[0052] In communication network 100, network device 110 can communicate data and control information to terminal device 120, and terminal device 120 can also communicate data and control information to network device 110. The link from network device 110 to terminal device 120 is called a downlink (DL), and the link from terminal device 120 to network device 110 is called an uplink (UL).

[0053] Communications in network 100 may conform to any suitable standard, including, but not limited to, Global System for Mobile Communications (GSM), Long Term Evolution (LTE), LTE Evolution, LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), and GSM EDGE Radio Access Network (GERAN). Furthermore, communications may be performed according to any generation of communication protocols currently known or developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, and fifth generation (5G) communication protocols.

[0054] In order to obtain the CSI of the communication channel between the network device 110 and the 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. The terminal device 120 may then determine the CSI of the communication channel based on the obtained channel information and the corresponding codebook. For example, the obtained channel information may be quantized into CSI based on the corresponding codebook. The terminal device 120 may report the CSI to the network device 110. The process for reporting CSI is also referred to as "CSI feedback". The CSI can ensure the reliability of wireless communication between the network device 110 and the terminal device 120. As mentioned above, for CSI signaling, an important aspect is the arrangement of the components of the compressed PMI in the uplink control information (UCI) message.

[0055] Figure 2 A schematic diagram of a process 200 for UCI design according to an example embodiment of the present disclosure is shown. For discussion purposes, reference will be made to Figure 1 To describe process 200. Process 200 may involve Figure 1 The network device 120 and the terminal device 110 are shown.

[0056] like Figure 2 As shown, terminal device 120 determines 210 a matrix characterizing a channel between terminal device 120 and network device 110. The matrix may have spatial and frequency components and correspond to a bitmap indicating a set of non-zero linear combination coefficients used to quantize the channel.

[0057] In some example embodiments, terminal device 120 may receive downlink control information received from network device 110 and obtain resource indications associated with spatial components and frequency components, which are known to both the terminal device and the network device. Terminal device 120 may determine a matrix based on the downlink control information and the resource indications.

[0058] Figure 3A and Figure 3B Such a matrix and the corresponding bitmap are shown in FIG. Figure 3A As shown, the matrix has spatial components in the spatial domain 310 and frequency components in the frequency domain 320 . Figure 3A Such a matrix as shown may be referred to as an LC coefficient matrix.

[0059] As mentioned above, this matrix can be obtained by applying compression to the PMI matrix representing the set of precoding vectors for a given spatial layer for all configured subbands, which can be indicated in the downlink control information received from network device 110. Given a PMI matrix W of size 2N1N2×N3, where N1×N2 is the number of antenna ports used to transmit for each polarization in a two-dimensional cross-polarized antenna array, and N3 is the number of configured PMI subbands. For a rank indicator (RI) greater than one, there is one such PMI matrix for each RI spatial layer. The compression operation on the PMI matrix W is linear and can be expressed by the following equation:

[0060]

[0061] The column vectors of the matrix W1 are the components of the SD orthogonal basis of size 2L, W f The columns of form an FD orthogonal basis of size M, and is a 2L×M matrix of complex-valued LC coefficients. Can refer to Figure 3A To further reduce signaling overhead, only a subset of the 2LM LC coefficients is reported, and the remaining coefficients are set to zero. This set of reported LC coefficients is called the non-zero (NZ) coefficients. The NZ coefficients can refer to Figure 3A The cells in which ∑ is not equal to zero, for example, cell 331.

[0062] Therefore, the PMI report of a layer can be composed of two indicators for SD and FD basis subset selection respectively and an indicator K in the matrix NZ The position of the non-zero coefficients is composed of a 2L×M bitmap. The bitmap of the matrix can be found in Figure 3B As shown in Figure 3A and Figure 3B As shown, the rows and columns of the bitmap may 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.

[0063] K in the matrix NZThe target coefficient exists among the non-zero coefficients. The target coefficient can be referred to as the largest coefficient among the non-zero coefficients, that is, the strongest coefficient. To reduce the overhead of reporting the indication of the strongest coefficient, terminal device 120 determines a shift operation of the frequency components of the matrix so that the strongest coefficient is located in the frequency component with a predetermined index.

[0064] In some example embodiments, terminal device 120 may determine an index of a frequency component and perform a modulo operation on the frequency component in the matrix based on the index of the frequency component, the number of frequency components in a set of predefined frequency components, the predetermined index, and a reference index of the frequency component. The reference index may indicate a frequency component associated with the target coefficient before the shift. Terminal device 120 may perform the shift operation based on the result of the modulo operation.

[0065] For example, let N3 be the number of frequency components, M<N3 is a matrix with indices m0, m1, ..., m M-1 The size of the frequency domain basis formed by the frequency components of is the index of the frequency component with the strongest coefficient. For example, suppose the component The predefined index value of is 0. The terminal device 120 may perform the shift operation based on the following equation:

[0066]

[0067] The terminal device 120 then determines an indication of the strongest coefficient, ie, the SCI, based on the spatial component in which the strongest coefficient is located. The SCI may indicate the spatial component in the matrix associated with the target coefficient.

[0068] The terminal device 120 further generates another indication indicating a frequency range associated with the subset of frequency components based on the predetermined index and the frequency component. That is, the subset of frequency components does not include the frequency component with the predetermined index.

[0069] In some example embodiments, terminal device 120 may determine a target frequency component associated with a predetermined index from the frequency components, and select a subset of frequency components that does not include the target frequency component from the frequency components. Terminal device 120 may determine an index of the subset of frequency components, and generate an indication indicating the frequency range based on the index of the subset of frequency components.

[0070] Referring back to the assumptions associated with equation (2), the terminal device 120 may report a subset of frequency components of size M-1 without the "0th" frequency component as follows:

[0071]

[0072] After determining the SCI and the indication associated with the frequency range, the terminal device 120 may transmit 220 uplink control information including both indications to the network device 110 .

[0073] It should be understood that the UCI may include other necessary messages for reporting relevant parameters for estimating the channel state.

[0074] In some example embodiments, the UCI may also include a bitmap corresponding to the matrix of LC coefficients. The bitmap may be determined based on the matrix before the shift operation. As mentioned above, such a bitmap may indicate the position of the NZ coefficients in the matrix. After the shift operation on the matrix, the bitmap may also be updated based on a predetermined index.

[0075] In some example embodiments, the terminal device 120 may determine a correspondence between a predetermined index and each of the indexes of the frequency components based on the indexes of the frequency components and the predetermined index, and update the bitmap based on the correspondence.

[0076] In some example embodiments, the terminal device 120 transmits uplink control information that also includes the updated bitmap.

[0077] refer to Figures 3A to 3B and Figures 4A to 4B , the shift operation can be clearly shown. As mentioned above, Figure 3A The matrix of may have a size of 2L*M, in which there is a set of NZ coefficients, and Figure 3B Shown is the corresponding Figure 3A The bitmap of the matrix. Figure 3A As shown, it is assumed that the strongest coefficient 330 is located in the first frequency component 341. For example, the terminal device 120 may shift the matrix so that the strongest coefficient is located in the 0th frequency component. The shifted matrix may be Figure 4A The strongest coefficient 330 is located in the 0th frequency component 340. Accordingly, Figure 3B The bitmap shown can be updated to Figure 4B The bitmap shown.

[0078] If we assume without loss of generality that Figure 4A If the row-by-row reading order of the bitmap in , the strongest coefficient is the third NZ coefficient, so without the proposal of the present disclosure, it will be used Bit indication: SCI=2 or 0010 (4-bit binary representation of 2). The value K of this layer NZ = 10 should also be reported in “UCI Part 1”.

[0079] According to the solution of the present disclosure, if the predetermined index is "0th", then Figure 3AIn the example of , the terminal device 120 may apply the shift operation to the frequency component one position to the left. For example, assuming that the frequency components are {m0, m1, ..., m M-1} = {0, 1, 3, 5, 10, 11, 12}, where the index of the FD component with the strongest coefficient is given by After cyclic shift and reordering, the FD basis subset is given by {0, 2, 3, 9, 10, 11, 12}. On the other hand, the FD basis subset indexed by the reporting SD component is bits to indicate SCI, in this example: SCI=1 or 001 (3-bit binary representation of 1).

[0080] Reference again Figure 2 , the network device 110 receives uplink control information from the terminal device 120 and determines state information of the channel based on the uplink control information.

[0081] In some example embodiments, network device 110 may determine a matrix based on the uplink control information and determine the state information based on the matrix. As mentioned above, the matrix may be obtained by applying compression to the PMI matrix. Network device 110 needs to reconstruct the PMI matrix based on the matrix. Based on the UCI, network device 110 may determine a subset of frequency components that does not include the target frequency component, and network device 110 may reconstruct the PMI by adding the target frequency component to the subset of frequency components.

[0082] In this way, the new solution for designing UCI can reduce the overhead for reporting parameters in "UCI Part 1" and "UCI Part 2".

[0083] The principle of cyclic shifting will be explained below. As mentioned above, any cyclic shift applied to a frequency component is equivalent to multiplying the PMI column by a phase ramp before applying frequency compression. This phase ramping operation performed at the terminal device 120 does not need to be reported to the network device 110 because it is transparent to the precoder design.

[0084] It is well known that phase rotation across the columns of precoding matrix W does not affect precoder performance, so network device 110 can reconstruct W without affecting performance until each column has a phase adjustment. This is true for any type of precoder design. It will be shown that the phase adjustments applied across the columns of matrix W2 prior to frequency domain compression do not need to be reported to network device 110. It will also be noted that the choice of these phases is an important degree of freedom that terminal device 120 can use to improve frequency compression (i.e., reduce reconstruction errors at network device 110).

[0085] First, consider the ideal case of frequency compression without basis subset selection, i.e., assuming M = N3, and where all 2LN3 unquantized frequency-domain coefficients are reported. Note that this is only an assumption, as there is no actual compression gain in the frequency domain. Assume that the terminal device 120 applies phase adjustment to the columns of W2 before DFT processing across subbands, and denote by R the diagonal matrix of arbitrary phase rotations:

[0086]

[0087] If network device 110 knows R, then precoder W is reconstructed as:

[0088]

[0089] However, if network device 110 does not know R, then reconstruction yields:

[0090]

[0091] In this ideal case, we observe that the difference between reconstructions (5) and (6) is only the phase rotation across the columns of the precoder, i.e.,

[0092] W=W(R)R (7)

[0093] And 2) assuming perfect reporting of the 2L×N3 linear combination matrix W2, applying the phase rotation in (4) is irrelevant.

[0094] Consider the realistic case of basis subset selection and quantization of linear combination coefficients with M≤N3, and say is a 2K×N3 matrix of FD coefficients known at network device 110. Note that only The K0 coefficients of are non-zero. Quantization error will also affect the non-zero coefficients. An error matrix is ​​introduced between the actual matrix and the ideal matrix of the linear combination coefficients:

[0095]

[0096] So that in the very general case, can be expressed as:

[0097]

[0098] If the network device 110 knows the phase shift R, then in the presence of errors, the precoder W' is reconstructed as:

[0099]

[0100] If network device 110 does not know R, the precoder reconstructs:

[0101]

[0102] By comparing (10) and (11), we can get:

[0103] W′=W′(R)R (12)

[0104] That is, the difference between two reconstructions with and without R reported is the phase rotation applied to the precoder columns, which does not affect precoder performance. However, unlike the ideal case, applying the appropriate phase rotation at the terminal device does have an impact on the reconstruction error. In fact, the terminal device can optimize the choice of phase rotation R so that the reconstruction error E is minimized according to a certain metric, even if the network device is unaware of these phase adjustments.

[0105] It should be noted that when W f When it is 2L×M instead of 2L×N3, both results (7) and (12) hold, but the expressions of W′ and W′(R) are more complicated because is no longer the identity matrix.

[0106] In summary, when frequency domain compression is applied, optimization of the phase adjustment E can be used by the terminal device to improve PMI accuracy. However, these adjustments do not need to be communicated to the network device to achieve this gain.

[0107] It should be noted that several operations can be expressed by these phase rotations. The oversampled DFT codebook can be described as the union of O3 cyclically shifted versions of the critically sampled codebook, where the smallest shift is a fractional number. Therefore, the selection of one of the O3 orthogonal groups of size N3 can be expressed by using notation (3), where R is given by the phase ramp:

[0108]

[0109] and k∈[0, ..., O3-1]. Similarly, the cyclic shifts of the N3 frequency domain candidate components can be obtained by applying a phase ramp across the columns of W2 with a minimum shift multiple of O3 in the original domain. For example, the cyclic shift that moves the FD component of index n to position '0' can be expressed by (4), where R is given by the phase ramp:

[0110]

[0111] and n∈[0,...,N3-1]. Finally, oversampling and cyclic shifting can also be combined with phase adjustments on the columns of W2 to ensure smooth phase transitions along its rows and avoid 'phase jumps' before applying frequency domain compression. Denote the diagonal matrix of these phase adjustments as R φ .

[0112]

[0113] where φ n ∈[0, 2π). In general, the terminal device can apply a combination of these three operations (oversampling, cyclic shift, phase adjustment) by performing a set of phase rotations on the columns of W2, as described in (4), where the rotation matrix is ​​given by:

[0114]

[0115] Will refer to Figures 5 and 6 More details of example embodiments according to the present disclosure are described.

[0116] Figure 5 1 shows a flow chart of an example method 500 for UCI design according to some example embodiments of the present disclosure. Figure 1 The method 500 is implemented at the terminal device 120 shown. For the purpose of discussion, reference will be made to Figure 1 Method 500 will be described.

[0117] At 510 , the terminal device 110 determines 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 a spatial component and a frequency component.

[0118] In some example embodiments, terminal device 110 may receive downlink control information received from a network device and obtain resource indications associated with spatial components and frequency components.Terminal device 110 may also determine a matrix based on the downlink control information and the resource indications.

[0119] At 520 , the terminal device 110 cyclically shifts the frequency components of the matrix so that the target coefficient in the set of non-zero linear combination coefficients is located in a frequency component having a predetermined index among the frequency components in the shifted matrix.

[0120] In some example embodiments, terminal device 110 may determine an index of the frequency component. Terminal device 110 may also determine a reference index from the index of the frequency component, the reference index indicating the frequency component associated with the target coefficient in the matrix, and shift the frequency component based on the index of the frequency component, the predetermined index, and the reference index.

[0121] At 530 , the terminal device 110 generates a first indication indicating a spatial component in the matrix associated with the target coefficient.

[0122] In some example embodiments, the terminal device 110 may determine a maximum coefficient from the set of non-zero linear combination coefficients as a target coefficient, and generate the first indication based on an index of a spatial component associated with the target coefficient in the matrix.

[0123] At 540 , the terminal device 110 transmits uplink control information including the first indication to the network device 120 .

[0124] In some example embodiments, the terminal device 110 may determine a bitmap based on the shifted matrix, the bitmap indicating positions of non-zero linear combination coefficients in the shifted matrix; and transmit uplink control information including the bitmap.

[0125] In some example embodiments, the terminal device 110 may generate a second indication indicating a frequency range associated with the subset of frequency components based on the predetermined index and the frequency components, and transmit uplink control information including the second indication.

[0126] In some example embodiments, terminal device 110 may determine a target frequency component associated with a predetermined index from the frequency components, and select a subset of frequency components that does not include the target frequency component from the frequency components. Terminal device 110 may also determine an index of the subset of frequency components after the shift, and generate a second indication based on the index of the subset of frequency components.

[0127] Figure 6 6 shows a flow chart of an example method 600 for UCI design according to some example embodiments of the present disclosure. Figure 1 The method 600 is implemented at the network device 110 shown. For the purpose of discussion, reference will be made to Figure 1 Method 600 will be described.

[0128] At 610, the network device 110 receives, at the network device and from the terminal device 120, uplink control information including a first indication of a spatial component 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 the spatial component and a frequency component.

[0129] At 620 , network device 110 determines state information of the channel based on the uplink control information.

[0130] In some example embodiments, network device 110 may determine a matrix based on the uplink control information and determine the state information based on the matrix.

[0131] In some example embodiments, network device 110 may receive uplink control information including a bitmap indicating positions of non-zero linear combination coefficients in a shifted matrix obtained by cyclically shifting frequency components of the matrix.

[0132] In some example embodiments, network device 110 may receive uplink control information including a second indication indicating a frequency range associated with the subset of frequency components.

[0133] In some example embodiments, a device capable of executing method 500 (e.g., implemented at terminal device 110) may include a component for executing the corresponding steps of method 500. The component may be implemented in any suitable form. For example, the component may be implemented as a circuit system or a software module.

[0134] In some example embodiments, the apparatus includes: means for determining, at a terminal device, a matrix comprising a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and a network device, the matrix having a spatial component and a frequency component; means for cyclically shifting the frequency components of the matrix so that a target coefficient in the set of non-zero linear combination coefficients is located in a frequency component having a predetermined index among the frequency components in the shifted matrix; means for generating a first indication indicating a spatial component in the matrix associated with the target coefficient; and means for transmitting uplink control information including the first indication to the network device.

[0135] In some example embodiments, a device capable of performing method 600 (e.g., implemented at network device 120) may include components for performing the corresponding steps of method 600. The components may be implemented in any suitable form. For example, the components may be implemented as a circuit system or a software module.

[0136] In some example embodiments, the apparatus includes: a component for receiving, at a network device and from a terminal device, uplink control information including a first indication, the first indication including a spatial component associated with a target coefficient in a matrix of a set of non-zero linear combination coefficients for quantizing a channel between the terminal device and the network device, the matrix having a spatial component and a frequency component; and a component for determining state information of the channel based on the uplink control information.

[0137] Figure 7 is a simplified block diagram of an apparatus 700 suitable for implementing an example embodiment of the present disclosure. The apparatus 700 may be provided to implement a communication apparatus, such as Figure 1The terminal device 120 and the network device 110 are shown. As shown, 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.

[0138] TX / RX 740 is used for bidirectional communication. TX / RX 740 has at least one antenna to facilitate communication. A communication interface may represent any interface necessary to communicate with other network elements.

[0139] Processor 710 may be of any type suitable for use in a local technology network and may include one or more of the following: as non-limiting examples, a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. Device 700 may have multiple processors, such as application specific integrated circuit chips, that are time-slave to a clock that synchronizes a master processor.

[0140] The 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 disks, compact disks (CDs), digital video disks (DVDs), and other magnetic 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 will not persist for the duration of a power outage.

[0141] Computer program 730 includes computer executable instructions executed by associated processor 710. Program 730 may be stored in ROM 1020. Processor 710 may perform any suitable actions and processes by loading program 730 into RAM 720.

[0142] The embodiment of the present disclosure can be implemented with the help of program 730, so that the device 700 can execute the Figure 2 to any of the processes of the present disclosure discussed above with respect to Figure 4. The embodiments of the present disclosure may also be implemented in hardware or in a combination of software and hardware.

[0143] In some embodiments, the program 730 may be tangibly embodied in a computer-readable medium that may be included in the device 700 (such as in the memory 720) or in other storage devices accessible by the device 700. The device 700 may load the program 730 from the computer-readable medium into the RAM 722 for execution. The computer-readable medium may include any type of tangible, non-volatile storage device, such as a ROM, EPROM, flash memory, hard disk, CD, DVD, etc. Figure 8 An example of a computer readable medium 800 is shown in the form of a CD or DVD. The computer readable medium has a program 730 stored thereon.

[0144] In general, various embodiments of the present disclosure may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure are shown and described as block diagrams, flow charts, or using some other graphical representation, it will be understood that the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general-purpose hardware, or a controller or other computing device, or some combination thereof, as non-limiting examples.

[0145] The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, which are executed on a target real or virtual processor in a device to perform the above-referenced Figure 2 4 . Generally speaking, a program module includes a routine, program, library, object, class, component, data structure, etc. that performs a specific task or implements a specific abstract data type. In various embodiments, the functionality of the program modules can be combined or split between program modules as needed. The machine executable instructions for the program modules can be executed in a local device or a distributed device. In a distributed device, the program modules can be located in both local storage media and remote storage media.

[0146] The program code for performing the methods of the present disclosure may be written in any combination of one or more programming languages. These program codes 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 executed by the processor or controller, the program code causes the functions / operations specified in the flow charts and / or block diagrams to be implemented. The program code may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0147] In the context of the present disclosure, computer program code or related data can be carried by any suitable carrier to enable an apparatus, device or processor to perform various processes and operations as described above. Examples of carriers include signals, computer-readable media, etc.

[0148] The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or apparatus, or any suitable combination of the foregoing. More specific examples of computer-readable storage media would include: an electrical connection having one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0149] In addition, although operation is described in a specific order, this should not be understood as needing to perform such operation in the specific order shown or in a continuous order or needing to perform all described operations to realize desired result. In some cases, multi-tasking and parallel processing can be advantageous. Similarly, although some implementation details have been included in the above discussion, these should not be understood as limiting the scope of the present disclosure, but rather as a description of the features that can be specific to a particular embodiment. Some features described in the context of a separate embodiment also can be realized in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment also can be realized in a plurality of embodiments individually or in any suitable subcombination.

[0150] Although the present disclosure has been described in language specific to structural features and / or methodological acts, it will be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method for signaling uplink control information, the uplink control information comprising an indication of an indication matrix having 2L×M complex-valued linear combination coefficients that can be arranged in 2L spatial components and M frequency components for quantizing a channel between a terminal device and a network device, wherein the matrix has K NZ non-zero linear combination coefficients, the method comprising: determining a bitmap indicating positions of non-zero linear combination coefficients after the frequency components of the matrix are cyclically shifted so that the strongest coefficient of the matrix is ​​located in the frequency component with a predetermined index; Generate a ones-bit strongest coefficient indicator indicating the index of the spatial component associated with the strongest coefficient of the matrix; as well as The uplink control information is transmitted to the network device, the uplink control information including the strongest coefficient indicator, the bitmap indicating positions of non-zero linear combination coefficients and values ​​of the non-zero linear combination coefficients, wherein the transmitted values ​​of the non-zero linear combination coefficients do not include the strongest coefficient.

2. The method of claim 1, wherein the method comprises: receiving downlink control information from the network device; obtaining a resource indication associated with the spatial component and the frequency component; as well as The matrix is ​​determined based on the downlink control information and the resource indication.

3. The method of claim 1 , comprising shifting the frequency components by: determining an index of the frequency component; determining a reference index from the indices of the frequency components, the reference index indicating the frequency component associated with the strongest coefficient in the matrix; and The frequency component is shifted based on the index of the frequency component, the predetermined index, and the reference index.

4. A method comprising: receiving, at a network device and from a terminal device, uplink control information transmitted using the method according to any one of claims 1 to 3; State information of the channel is determined based on the uplink control information.

5. A device for signaling uplink control information, the uplink control information comprising an indication of an indication matrix, the matrix having 2L×M complex-valued linear combination coefficients that can be arranged in 2L spatial components and M frequency components for quantizing a channel between a terminal device and a network device, wherein the matrix has K NZ non-zero linear combination coefficients, the device comprising: at least one processor; and at least one memory comprising computer program code, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least: determining a bitmap indicating positions of non-zero linear combination coefficients after the frequency components of the matrix are cyclically shifted so that the strongest coefficient of the matrix is ​​located in the frequency component with a predetermined index; Generate a ones-bit strongest coefficient indicator indicating the index of the spatial component associated with the strongest coefficient of the matrix; as well as The uplink control information is transmitted to the network device, the uplink control information including the strongest coefficient indicator, the bitmap indicating positions of non-zero linear combination coefficients and values ​​of the non-zero linear combination coefficients, wherein the transmitted values ​​of the non-zero linear combination coefficients do not include the strongest coefficient.

6. The apparatus of claim 5, wherein the apparatus is caused to: receiving downlink control information from the network device; obtaining a resource indication associated with the spatial component and the frequency component; and The matrix is ​​determined based on the downlink control information and the resource indication.

7. The apparatus of claim 5 , wherein the apparatus is caused to shift the frequency component by: determining an index of the frequency component; determining a reference index from the indices of the frequency components, the reference index indicating a frequency component associated with the maximum coefficient in the matrix; The frequency component is shifted based on the index of the frequency component, the predetermined index, and the reference index.

8. A non-transitory computer-readable medium comprising program instructions for causing a device to at least perform the method according to any one of claims 1 to 4.

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