Millimeter-wave MIMO beam-domain channel modeling method and system

Abstract

This invention relates to a beam domain modeling method based on massive MIMO, comprising establishing a geometric domain CIR system model characterizing the MIMO channel, performing beam domain transformation through a unitary matrix to obtain a beam domain CIR system model, wherein the scattering environment between the transmitter and receiver in the beam domain CIR system model is modeled as single-hop clusters and double-hop clusters; performing 3D modeling of the single-hop and double-hop clusters to obtain a 3D model of the coexistence of single-hop and double-hop clusters; and using the line-of-sight theory to model the line-of-sight of the single-hop and double-hop clusters on a planar antenna array, generating the position and length of the line-of-sight of the single-hop and double-hop clusters in the horizontal and vertical directions to characterize the channel nonstationarity. This invention considers the rich scattering characteristics of the MIMO channel, introduces single / double-hop clusters, describes the line-of-sight of the clusters on the planar antenna array, simulates the spatiotemporal-frequency nonstationarity of the massive MIMO channel, and simulation results show that the modeling method has good effectiveness.

Description

Technical Field

[0001] The present invention relates to the technical field of channel modeling, and in particular to a beam domain modeling method and system based on millimeter wave MIMO. Background Art

[0002] In massive MIMO systems, base stations are equipped with a large number of antennas, resulting in huge transceiver complexity. Converting the system channel from the spatial domain to the beam domain is an effective solution. Beam domain channel modeling characterizes the power coupling between the transmit and receive beams by sampling the propagation environment in the angle domain. As the number of antennas increases, the channel elements in the beam domain tend to be uncorrelated, the fading of the channel elements decreases, and they exhibit frequency flatness characteristics.

[0003] With the increasing shortage of wireless spectrum resources, the development of millimeter wave bands has become one of the research hotspots in the field of communications. Compared with the frequency bands below 6 GHz, the massive MIMO channels in the millimeter wave bands have more significant scattering effects and high attenuation due to the complex rich scattering environment. For millimeter wave band beam domain modeling, more accurate subdivision cluster modeling is needed to characterize the distribution of millimeter wave band clusters.

[0004] Many beam-domain channel studies and measurement results show that the introduction of massive MIMO technology makes the spatial non-stationary characteristics of clusters in beam-domain channels non-negligible. Therefore, it is crucial to establish an accurate massive MIMO beam-domain channel model in the millimeter-wave frequency band. Generally speaking, there are two different methods for channel modeling to characterize the non-stationarity of clusters: the first is the birth-death (BD) process, which focuses on the temporal evolution of cluster groups; the second is the cluster visibility region (VR) method, where VR refers to an area on the antenna array, and each cluster is assigned to a specific VR. The antenna can only observe the corresponding cluster when it is in the VR. Therefore, it is crucial to establish a massive MIMO beam-domain channel model in the millimeter-wave frequency band to characterize the spatial non-stationarity. Summary of the invention

[0005] To this end, the technical problem to be solved by the present invention is to propose a beam domain modeling method and system based on millimeter wave MIMO, which takes into account the rich scattering characteristics of the MIMO channel, introduces single / double-hop clusters, and describes the visible area of ​​the cluster on the antenna planar array, simulating the spatio-temporal and frequency non-stationarity of large-scale MIMO channels. Simulation results show that the modeling method has good effectiveness.

[0006] In order to solve the above technical problems, the present invention provides a beam domain modeling method based on millimeter wave MIMO, comprising the following steps:

[0007] S1. Establish a geometric domain CIR system model that characterizes the MIMO channel, and perform beam domain conversion through a unitary matrix to obtain a beam domain CIR system model, wherein the beam domain CIR system model adopts a composite mechanism of single-hop and double-hop propagation, and the scattering environment between the transmitter and the receiver corresponding to the beam domain CIR system model is modeled as a single-hop cluster and a double-hop cluster;

[0008] S2. Based on the rich scattering characteristics of the millimeter wave channel, the parameters of the single-hop cluster and the double-hop cluster in S1 are 3D modeled to obtain a 3D model of the composite existence of the single-hop cluster and the double-hop cluster, wherein the 3D modeling includes the geometric distribution, angle, delay and power of the single-hop cluster and the double-hop cluster;

[0009] S3. Use the visible area theory to model the visible areas of single-hop clusters and double-hop clusters on the planar antenna array, and generate the positions and lengths of the visible areas of single-hop clusters and double-hop clusters in the horizontal and vertical directions to characterize the non-stationarity of the channel.

[0010] In one embodiment of the present invention, the single-hop cluster and the double-hop cluster in S1 are represented as follows: the single-hop cluster represents a virtual link from the transmitter to the single-hop cluster and then to the receiver; a pair of double-hop clusters represents a virtual link consisting of the first bounce from the transmitter to the first reflection cluster and the last bounce from the last reflection cluster to the receiver and multiple bounces between the first bounce and the last bounce.

[0011] In one embodiment of the present invention, the method of establishing a geometric domain CIR system model characterizing a MIMO channel in S1 and performing beam domain conversion through a unitary matrix to obtain the beam domain CIR system model includes:

[0012] S1.1. Establish the geometric domain CIR system model as follows:

[0013]

[0014] in,

[0015]

[0016]

[0017]

[0018] In the formula, h i，j (τ) represents the impulse response between the antenna in the i-th row and j-th column of the transmitter and the receiver, SBC represents a single-hop cluster, DBC represents a double-hop cluster, LOS represents the line of sight, and K R represents the Rice factor, P k represents the normalized total power of the kth path between the transmitter and the receiver, η SBC and η DBCare the scattering power proportions of the single-hop cluster and the double-hop cluster, represents the impulse response between the transmitter and the receiver, where:

[0019]

[0020]

[0021] Where, d h and d v are the spacing between adjacent antennas in the uniform planar antenna array in azimuth and elevation, respectively. and denote the azimuths of the base station side and the user side of the kth path respectively; and denote the elevation angles of the base station side and the user side of the kth path, respectively, and v k represents the Doppler frequency shift, where f k =v / λ, λ represents the wavelength, v and α represent the moving speed and moving azimuth of the user side respectively; f c represents the carrier frequency, τ k represents the propagation delay of the kth path, Φ k represents the phase shift of the kth path;

[0022] S1.2, note middle The response matrix of a uniform planar antenna array is written as:

[0023]

[0024] S1.3. Introducing the transformation matrix Perform beam domain transformation and obtain:

[0025]

[0026] in:

[0027]

[0028]

[0029] In the formula, I s and I e They are respectively the starting index and the ending index of the antenna in the visible area on the uniform planar antenna array.

[0030] In one embodiment of the present invention, the method of performing 3D modeling on the parameters of the single / double-hop cluster in S2 includes:

[0031] S2.1, the geometric distribution of single / double-hop clusters is modeled based on the exponential distribution of the distances from the single / double-hop clusters to the transmitter and receiver;

[0032] S2.2, based on the fact that the azimuth angle of the single / double-hop cluster follows the von Mises distribution and the elevation angle follows the cosine distribution, the geometric distribution of the single / double-hop cluster is modeled;

[0033] S2.3. Obtain the distance vector of the single / double-hop cluster at the transmitter and receiver sides according to the angle parameter of the single / double-hop cluster, and model the delay, frequency shift, and phase shift of the single / double-hop cluster based on the distance vector;

[0034] S2.4. Model the power of single / double-hop clusters based on the delay obtained in S2.3.

[0035] In one embodiment of the present invention, the method of S2.1 includes: setting the distance from the single / double-hop cluster to the transmitting end and the receiving end to obey the exponential distribution: The geometric distribution of single / double hop clusters is obtained as Among them, k d Represents the distance parameter of the exponential distribution.

[0036] In one embodiment of the present invention, the method of S2.2 includes: setting the azimuth of the single / double hop cluster Follows von Mises distribution, elevation angle It follows a cosine distribution, where denote the azimuth and elevation angles between the single / double-hop cluster and the transmit antenna array center, respectively, denote the azimuth and elevation angles between the single / double-hop cluster and the center of the receiving antenna array, respectively.

[0037] In one embodiment of the present invention, the method of S2.3 includes:

[0038] Based on the angle parameter, the distance vector from the single / double hop cluster to the transmitter and receiver array center is obtained.

[0039] Where D represents the initial position vector of the receiver, They respectively represent exponential distributions. and The Frobenius norm of ;

[0040] The Doppler frequency shift and phase shift of the LoS component are:

[0041]

[0042]

[0043] The distance of the LoS path component

[0044] In the formula, express and The LoS distance vector between represents the transmitting antenna p, represents the antenna q at the receiving end, They are and The 3D position vector of and Respectively represent the maximum Doppler shift of the transmitting antenna and the receiving antenna, v T and v R are the relative velocity vectors of the transmitter and receiver, φ0 is the initial phase, λ is the wavelength, and <·,·> represents the inner product operation;

[0045] The Doppler frequency shift and phase shift of the SBC component are:

[0046]

[0047]

[0048] The distance of the SBC path component

[0049]

[0050] In the formula, and They are With the s-th single-hop cluster, The distance vector between the s-th single-hop cluster;

[0051] The Doppler frequency shift and phase shift of the DBC component are:

[0052]

[0053]

[0054] The distance of the DBC path component

[0055]

[0056] In the formula, and Respectively With the mth two-hop cluster, The distance vector between the nth two-hop cluster, represents virtual delay, D represents the distance between the transmitter and receiver, τ maxrepresents the maximum delay, and c represents the speed of light.

[0057] In one embodiment of the present invention, the method of S2.4 includes: the average power of the single / double-hop cluster on the kth path is:

[0058]

[0059] Among them, the virtual delay of the kth path is r τ represents the delay ratio, σ τ represents the randomly generated delay spread factor, u n represents a random variable that follows a uniform distribution, namely u n ~U(0,1),Z n Obey Gaussian distribution, that is, Z n ~N(0,σ k ), σ k Represents the shaded standard deviation of the one / two-hop clusters.

[0060] In one embodiment of the present invention, the method of S3 includes: performing visual area modeling on a planar antenna array to generate the visual area positions of the single / double-hop clusters in the horizontal and vertical directions:

[0061]

[0062] in, and are the start index and end index of the antenna array in the horizontal direction of the visible area of ​​the cluster, which obeys the uniform distribution. and are the start index and end index of the antenna array in the vertical direction of the visible area of ​​the cluster, and they obey the uniform distribution, that is, d h and d v Respectively represent the spacing between adjacent UPA antennas in azimuth and elevation.

[0063] In addition, the present invention also provides a beam domain modeling system based on millimeter wave MIMO, comprising:

[0064] A CIR construction and beam domain transformation module is used to establish a geometric domain CIR system model that characterizes a MIMO channel, and to perform beam domain transformation through a unitary matrix to obtain a beam domain CIR system model, wherein the beam domain CIR system model adopts a composite mechanism of single-hop and double-hop propagation, and the scattering environment between the transmitter and the receiver corresponding to the beam domain CIR system model is modeled as a single-hop cluster and a double-hop cluster;

[0065] The single-hop cluster and double-hop cluster modeling module is used to perform 3D modeling on the parameters of the single-hop cluster and the double-hop cluster in S1 based on the rich scattering characteristics of the millimeter wave channel, and obtain a 3D model of the composite existence of the single-hop cluster and the double-hop cluster, wherein the 3D modeling includes the geometric distribution, angle, delay and power of the single-hop cluster, and the geometric distribution, angle, delay, power and virtual absolute delay of the double-hop cluster:

[0066] The visible area modeling module is used to model the visible areas of single-hop clusters and double-hop clusters on a planar antenna array using the visible area theory, and generate the positions and lengths of the visible areas of the single-hop clusters and double-hop clusters in the horizontal and vertical directions to characterize the non-stationarity of the channel.

[0067] The above technical solution of the present invention has the following advantages compared with the prior art:

[0068] The present invention proposes a millimeter-wave MIMO beam-domain channel modeling method, which takes into account the rich scattering characteristics of the MIMO channel, introduces single / double-hop clusters, and describes the visible area of ​​the clusters on the antenna planar array, simulating the spatio-temporal and frequency non-stationarity of large-scale MIMO channels. Simulation results show that the modeling method has good effectiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 A schematic diagram of the flow of a millimeter-wave MIMO beam-domain channel modeling method proposed in the present invention.

[0070] Figure 2 The present invention is a schematic diagram of the millimeter wave beam domain channel scattering environment.

[0071] Figure 3 This is the contour diagram of the channel response when the visible area accounts for 0.

[0072] Figure 4 This is the contour diagram of the channel response when the visible area accounts for 0.4.

[0073] Figure 5 This is the contour diagram of the channel response when the visible area accounts for 0.8.

[0074] Figure 6 It is the MPC (multipath component part) position distribution diagram of the transmitting end UPA.

[0075] Figure 7 The following is a channel capacity analysis diagram of a 64x64 antenna array under different visible area ratios.

[0076] Figure 8 The following is a channel capacity analysis diagram of a 4x64 antenna array under different visible area ratios. DETAILED DESCRIPTION

[0077] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0078] Explanation of some terms in the present invention: impulse response (Channel lmpulse Model, CIR); uniform planar antenna array (Uniform Planar Array, UPA).

[0079] Reference Figure 1 and Figure 2 As shown, the present invention discloses a millimeter wave MIMO beam domain channel modeling method, comprising the following steps:

[0080] S1. Establish a geometric domain CIR system model that characterizes the MIMO channel, and perform beam domain conversion through a unitary matrix to obtain a beam domain CIR system model, wherein the beam domain CIR system model adopts a composite mechanism of single-hop and double-hop propagation, and the scattering environment between the transmitter and the receiver corresponding to the beam domain CIR system model is modeled as a single-hop cluster and a double-hop cluster;

[0081] S2. Based on the rich scattering characteristics of the millimeter wave channel, the parameters of the single-hop cluster and the double-hop cluster in S1 are 3D modeled to obtain a 3D model of the composite existence of the single-hop cluster and the double-hop cluster, wherein the 3D modeling includes the geometric distribution, angle, delay and power of the single-hop cluster and the double-hop cluster;

[0082] S3. Use the visible area theory to model the visible areas of single-hop clusters and double-hop clusters on the planar antenna array, and generate the positions and lengths of the visible areas of single-hop clusters and double-hop clusters in the horizontal and vertical directions to characterize the non-stationarity of the channel.

[0083] The present invention proposes a millimeter-wave MIMO beam-domain channel modeling method, which takes into account the rich scattering characteristics of the MIMO channel, introduces single / double-hop clusters, and describes the visible area of ​​the clusters on the antenna planar array, simulating the spatio-temporal and frequency non-stationarity of large-scale MIMO channels. Simulation results show that the modeling method has good effectiveness.

[0084] The single / double hop cluster in step S1 is represented as follows: k There are two cases: the first is represented by a single-hop cluster SBC, which is composed of the transmitter Tx to the single-hop cluster SBC and then to the receiver Rx; the second is represented by a pair of double-hop clusters DBC, which is composed of the transmitter Tx to the first reflection cluster DBC. T The first bounce and the last reflection cluster DBC R The abstract virtual link consists of the last bounce to the receiver Rx and multiple bounces between the first bounce and the last bounce.

[0085] Assuming the transmitter is stationary and the receiver is moving, the geometric domain channel impulse response is given by P h ×P v matrix Indicates that, h i，j (τ) is the impulse response between the i-th row and j-th column antenna of the transmitter Tx, i.e., the UPA (uniform planar antenna array) and the receiver Rx, i.e., the UT (user). The impulse response of the proposed beam-domain CIR system model can be calculated as:

[0086]

[0087] in,

[0088]

[0089]

[0090]

[0091] Among them, K R is the Rice factor; P k represents the normalized total power of the kth path between Tx and Rx; η SBC and η DBC are the scattering power proportions of single-hop and double-hop clusters, satisfying η SBC +η DBC =1; symbols f and φ are Doppler frequency and phase, which will be explained later; It is the impulse response between the transmitter Tx and the receiver Rx, specifically:

[0092]

[0093]

[0094] The first half of the expression is the response of the UPA at the transmitting end, and the second half is the frequency shift and phase shift caused by the movement of the UT at the receiving end. h and d v Respectively represent the spacing between adjacent UPA antennas in azimuth and elevation; and denote the azimuths of the base station side and the user side of the kth path respectively; and represent the elevation angles of the base station side and the user side of the kth path respectively; v k is the Doppler shift, f k =v / λ, λ is the wavelength, v and α are the moving speed and moving azimuth of the user side respectively; f c is the carrier frequency, τ k is the propagation delay of the kth path, Φk is the phase shift of the kth path and is uniformly distributed in [0, 2π), that is, Φ k ~U[0,2π).

[0095] Then the beam domain transformation is performed through the unitary matrix:

[0096] remember middle The response matrix of UPA can be written as:

[0097]

[0098] in,

[0099]

[0100]

[0101] Introducing the transformation matrix in,

[0102]

[0103]

[0104] Perform beam domain conversion:

[0105]

[0106] in,

[0107]

[0108] I s and I e They are respectively the starting index and the ending index of the antenna index of the visible area on the UPA.

[0109] The method for performing 3D modeling on the parameters of the single-hop cluster and the double-hop cluster in S1 in step S2 is:

[0110] S2.1, the geometric distribution of single / double-hop clusters is modeled based on the exponential distribution of the distances from the single / double-hop clusters to the transmitter and receiver;

[0111] S2.2, based on the fact that the azimuth angle of the single / double-hop cluster follows the von Mises distribution and the elevation angle follows the cosine distribution, the geometric distribution of the single / double-hop cluster is modeled;

[0112] S2.3. Obtain the distance vector of the single / double-hop cluster at the transmitter and receiver sides according to the angle parameter of the single / double-hop cluster, and model the delay, frequency shift, and phase shift of the single / double-hop cluster based on the distance vector;

[0113] S2.4. Model the power of single / double-hop clusters based on the delay obtained in S2.3.

[0114] Specifically, the contents of 3D modeling of the parameters of a single-hop cluster are as follows:

[0115] S21.1. Let the distance from the single-hop cluster to the transmitter and receiver obey the exponential distribution Geometric distribution of single-hop clusters:

[0116]

[0117] Among them, k d is the distance parameter of the exponential distribution;

[0118] S21.2, let the azimuth of the single-hop cluster be Follows von Mises distribution, elevation angle It follows a cosine distribution, where are the azimuth and elevation angles between the single-hop cluster and the center of the transmitting antenna array, respectively. are the azimuth and elevation angles between the single-hop cluster and the center of the receiving antenna array, respectively;

[0119] S21.3. Obtain the distance vector from the single-hop cluster to the center of the transmitter Tx and receiver Rx arrays according to the angle parameter.

[0120]

[0121] Where D is the initial position vector of the receiver Rx, They are exponentially distributed The Frobenius norm of ;

[0122] Distance of LoS path components in, yes and The LoS distance vector between is the transmitting antenna p, is the antenna q at the receiving end, They are and The 3D position vector of .

[0123] The Doppler frequency shift and phase shift of the LoS component are:

[0124]

[0125]

[0126] in, and are the maximum Doppler shifts of the transmitting and receiving antennas, respectively, and v T and v R are the relative velocity vectors of the transmitter and receiver, respectively. φ0 is the initial phase, λ is the wavelength, and <·,·> represents the inner product operation.

[0127] Distance of SBC path components

[0128] in, and They are With the s-th single-hop cluster, The distance vector between the s-th single-hop cluster, is the transmitting antenna p, is the antenna q at the receiving end, They are and The 3D position vector of .

[0129] The Doppler frequency shift and phase shift of the SBC component are:

[0130]

[0131]

[0132] in, and are the maximum Doppler shifts of the transmitting and receiving antennas, respectively, and v T and v R are the relative velocity vectors of the transmitter and receiver, φ0 is the initial phase, λ is the wavelength, and <·,·> represents the inner product operation;

[0133] S21.4, the average power of a single-hop cluster on the kth path is:

[0134]

[0135] Among them, the virtual delay of the kth path is r τ is the delay ratio, σ τ is a randomly generated delay spread factor, u n is a random variable that follows a uniform distribution, that is, u n ~U(0,1),Z n Obey Gaussian distribution, that is, Z n ~N(0,σ k ), σ k is the shadow standard deviation of the one-hop cluster.

[0136] Specifically, the contents of 3D modeling of the parameters of the double-hop cluster are as follows:

[0137] S22.1. Let the distance from the two-hop cluster to the transmitter and the receiver obey the exponential distribution Geometric distribution of two-hop clusters:

[0138]

[0139] Among them, k d is the distance parameter of the exponential distribution;

[0140] S22.2, let the azimuth of the double-hop cluster Follows von Mises distribution, elevation angle It follows a cosine distribution, where are the azimuth and elevation angles between the two-hop cluster and the center of the transmitting antenna array, respectively. are the azimuth and elevation angles between the two-hop cluster and the center of the receiving antenna array, respectively;

[0141] S22.3. Obtain the distance vector from the double-hop cluster to the center of the transmitter Tx and receiver Rx arrays according to the angle parameter.

[0142]

[0143] Where D is the initial position vector of the receiver Rx, They are exponentially distributed The Frobenius norm of ;

[0144] Distance of DBC path components

[0145]

[0146] in, and They are With the mth two-hop cluster, The distance vector between the nth two-hop cluster, is the transmitting antenna p, is the antenna q at the receiving end, They are and The 3D position vector of represents the virtual delay, which satisfies the uniform distribution, that is, D is the distance between the transmitter and receiver, τ max is the maximum delay and c is the speed of light.

[0147] The Doppler frequency shift and phase shift of the DBC component are:

[0148]

[0149] in, and are the maximum Doppler shifts of the transmitting and receiving antennas, respectively, and v T and v R are the relative velocity vectors of the transmitter and receiver, respectively. φ0 is the initial phase, λ is the wavelength, <·,·> represents the inner product operation, represents the virtual absolute delay, which satisfies the uniform distribution, that is, D is the distance between the transmitter and receiver, τ max is the maximum delay, c is the speed of light;

[0150] S22.4, the average power of the two-hop cluster on the kth path is:

[0151]

[0152] Among them, the virtual delay of the kth path is r τ is the delay ratio, σ τ is a randomly generated delay spread factor, u n is a random variable that follows a uniform distribution, that is, u n ~U(0,1),Z n Obey Gaussian distribution, that is, Z n ~N(0,σ k′ ), σ k′ is the shadow standard deviation of the double-hop cluster.

[0153] In step S3, visible area modeling is performed on the planar antenna array to generate visible area positions of the single-hop cluster in the horizontal and vertical directions:

[0154]

[0155] in, and are the start index and end index of the antenna array in the horizontal direction of the visible area of ​​the cluster, which obeys the uniform distribution. and are the start index and end index of the antenna array in the vertical direction of the visible area of ​​the cluster, and they obey the uniform distribution, that is, d h and d v They represent the spacing between adjacent antennas of the UPA in azimuth and elevation, respectively. The channel nonstationarity in the planar antenna array domain is not isotropic, that is, the visible area of ​​a single-hop cluster has different lengths in the horizontal and vertical directions.

[0156] In step S3, the visible area modeling is performed on the planar antenna array to generate the visible area positions of the double-hop cluster in the horizontal and vertical directions:

[0157]

[0158] in, and They are the start index and end index of the antenna array in the horizontal direction of the visible area of ​​the single-hop cluster, that is, they obey the uniform distribution. and They are the start index and end index of the antenna array in the vertical direction of the visible area of ​​the double-hop cluster, and they obey the uniform distribution, that is, d h and d v They represent the spacing between adjacent antennas of the UPA in azimuth and elevation, respectively. The channel nonstationarity in the planar antenna array domain is not isotropic, that is, the visible area of ​​the two-hop cluster has different lengths in the horizontal and vertical directions.

[0159] The technical solution of the present invention is further described and explained below in conjunction with specific embodiments.

[0160] The present invention selects the indoor office environment as the reference environment. In order to characterize the beam domain channel model, Figure 3-Figure 6 The response contour of the channel matrix H and the angular distribution of the transmitting ray are shown. The results show that the array non-stationarity of the massive MIMO channel increases the beamwidth and reduces the spatial resolution in the partial visible direction under different proportions of the partial visible area of ​​the single / double hop cluster, thus affecting the richness of the beam.

[0161] Theoretically, the channel capacity is proportional to the number of antennas, and the M×M antenna method has an M-fold channel capacity gain over the method using M×M antennas. Figure 7 and Figure 8 The simulation results are inconsistent with the theoretical results, which can be explained by the rich scattering characteristics of the beam domain channel. At the same time, the larger the proportion of the partial visible area of ​​the single / double-hop cluster, the smaller the channel capacity. This is because as the partial visible area increases, the beam becomes wider, causing power leakage, which is more obvious on larger-scale antenna arrays.

[0162] A beam domain modeling system based on millimeter wave MIMO disclosed in an embodiment of the present invention is introduced below. The beam domain modeling system based on millimeter wave MIMO described below and the beam domain modeling method based on millimeter wave MIMO described above can refer to each other.

[0163] The embodiment of the present invention further provides a beam domain modeling system based on millimeter wave MIMO, including:

[0164] A CIR construction and beam domain transformation module is used to establish a geometric domain CIR system model that characterizes a MIMO channel, and to perform beam domain transformation through a unitary matrix to obtain a beam domain CIR system model, wherein the beam domain CIR system model adopts a composite mechanism of single-hop and double-hop propagation, and the scattering environment between the transmitter and the receiver corresponding to the beam domain CIR system model is modeled as a single-hop cluster and a double-hop cluster;

[0165] A single-hop cluster and double-hop cluster modeling module, which is used to perform 3D modeling on the parameters of the single-hop cluster and the double-hop cluster in S1 based on the rich scattering characteristics of the millimeter wave channel, and obtain a 3D model of the composite existence of the single-hop cluster and the double-hop cluster, wherein the 3D modeling includes the geometric distribution, angle, delay and power of the single-hop cluster, and the geometric distribution, angle, delay, power and virtual absolute delay of the double-hop cluster;

[0166] The visible area modeling module is used to model the visible areas of single-hop clusters and double-hop clusters on a planar antenna array using the visible area theory, and generate the positions and lengths of the visible areas of the single-hop clusters and double-hop clusters in the horizontal and vertical directions to characterize the non-stationarity of the channel.

[0167] The beam domain modeling system based on millimeter wave MIMO of this embodiment is used to implement the aforementioned beam domain modeling method based on millimeter wave MIMO. Therefore, the specific implementation method of the system can be seen in the embodiment part of the beam domain modeling method based on millimeter wave MIMO in the previous text. Therefore, its specific implementation method can refer to the description of the corresponding embodiments of each part, which will not be introduced in detail here.

[0168] In addition, since the beam domain modeling system based on millimeter wave MIMO of this embodiment is used to implement the aforementioned beam domain modeling method based on millimeter wave MIMO, its function corresponds to that of the aforementioned method and will not be repeated here.

[0169] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0170] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0171] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0172] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0173] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A beam domain modeling method based on millimeter wave MIMO, characterized in that: The following steps are involved: S1. Establish a geometric domain CIR system model that characterizes the MIMO channel, and perform beam domain conversion through a unitary matrix to obtain a beam domain CIR system model, wherein the beam domain CIR system model adopts a composite mechanism of single-hop and double-hop propagation, and the scattering environment between the transmitter and the receiver corresponding to the beam domain CIR system model is modeled as a single-hop cluster and a double-hop cluster; S2. Based on the rich scattering characteristics of the millimeter wave channel, the parameters of the single-hop cluster and the double-hop cluster in S1 are 3D modeled to obtain a 3D model of the composite existence of the single-hop cluster and the double-hop cluster, wherein the 3D modeling includes the geometric distribution, angle, delay and power of the single-hop cluster and the double-hop cluster; S3. Use the visible area theory to model the visible areas of the single-hop cluster and the double-hop cluster on the planar antenna array, and generate the positions and lengths of the visible areas of the single-hop cluster and the double-hop cluster in the horizontal and vertical directions to characterize the non-stationarity of the channel. The method of establishing a geometric domain CIR system model for characterizing a MIMO channel in S1 and performing beam domain transformation through a unitary matrix to obtain the beam domain CIR system model includes: S1.

1. Establish the geometric domain CIR system model as follows: in, In the formula, h i，j (τ) represents the impulse response between the antenna in the i-th row and j-th column of the transmitter and the receiver, SBC represents a single-hop cluster, DBC represents a double-hop cluster, LoS represents the line-of-sight portion, and K R represents the Rice factor, P k represents the normalized total power of the kth path between the transmitter and the receiver, η SBC and η DBC are the scattering power proportions of the single-hop cluster and the double-hop cluster, represents the impulse response between the transmitter and the receiver, where and Where, d h and d v are the spacing between adjacent antennas in the uniform planar antenna array in azimuth and elevation, respectively. and represent the azimuth angles of the base station side and the user side of the kth path respectively; and represent the elevation angles of the base station side and the user side of the kth path respectively; v k represents the Doppler frequency shift, where f k =v / λ, λ represents the wavelength, v and α represent the moving speed and moving azimuth of the user side respectively; f c represents the carrier frequency, τ k represents the propagation delay of the kth path, Φ k represents the phase shift of the kth path; S1.2, note middle The response matrix of a uniform planar antenna array is written as: S1.

3. Introducing the transformation matrix Perform beam domain transformation and obtain: in: In the formula, I s and I e are the start index and end index of the antenna in the visible area on the uniform planar antenna array, respectively; The method for performing 3D modeling on the parameters of the single / double-hop cluster in S2 includes: S2.1, the geometric distribution of single / double-hop clusters is modeled based on the exponential distribution of the distances from the single / double-hop clusters to the transmitter and receiver; S2.2, based on the fact that the azimuth angle of the single / double-hop cluster follows the von Mises distribution and the elevation angle follows the cosine distribution, the geometric distribution of the single / double-hop cluster is modeled; S2.

3. Obtain the distance vector of the single / double-hop cluster at the transmitter and receiver sides according to the angle parameter of the single / double-hop cluster, and model the delay, frequency shift, and phase shift of the single / double-hop cluster based on the distance vector; S2.

4. Model the power of single / double-hop clusters based on the delay obtained in S2.

3.

2. The beam domain modeling method based on millimeter wave MIMO according to claim 1, characterized in that: The single-hop cluster and the double-hop cluster in S1 are represented as follows: the single-hop cluster represents a virtual link from the transmitter to the single-hop cluster and then to the receiver; a pair of double-hop clusters represents a virtual link consisting of the first bounce from the transmitter to the first reflection cluster and the last bounce from the last reflection cluster to the receiver and multiple bounces between the first bounce and the last bounce.

3. The beam domain modeling method based on millimeter wave MIMO according to claim 1, characterized in that: The method of S2.1 includes: setting the distance from the single / double-hop cluster to the transmitting end and the receiving end to obey the exponential distribution: The geometric distribution of single / double hop clusters is obtained as Among them, k d Represents the distance parameter of the exponential distribution.

4. The beam domain modeling method based on millimeter wave MIMO according to claim 1, characterized in that: The method of S2.2 includes: setting the azimuth of the single / double hop cluster Follows von Mises distribution, elevation angle It follows a cosine distribution, where denote the azimuth and elevation angles between the single / double-hop cluster and the transmit antenna array center, respectively, denote the azimuth and elevation angles between the single / double-hop cluster and the center of the receiving antenna array, respectively.

5. The beam domain modeling method based on millimeter wave MIMO according to claim 1, characterized in that: The method of S2.3 comprises: Based on the angle parameter, the distance vector from the single / double hop cluster to the transmitter and receiver array center is obtained. Where D represents the initial position vector of the receiver, They respectively represent exponential distributions. and The Frobenius norm of ; The Doppler frequency shift and phase shift of the LoS component are: The distance of the LoS path component In the formula, express and The LoS distance vector between represents the transmitting antenna p, represents the antenna q at the receiving end, They are and The 3D position vector of and Respectively represent the maximum Doppler shift of the transmitting antenna and the receiving antenna, v T and v R are the relative velocity vectors of the transmitter and receiver, φ0 is the initial phase, λ is the wavelength, and <·,·> represents the inner product operation; The Doppler frequency shift and phase shift of the SBC component are: The distance of the SBC path component In the formula, and They are With the s-th single-hop cluster, The distance vector between the s-th single-hop cluster; The Doppler frequency shift and phase shift of the DBC component are: The distance of the DBC path component In the formula, and Respectively With the mth two-hop cluster, The distance vector between the nth two-hop cluster, represents virtual delay, D represents the distance between the transmitter and receiver, τ max represents the maximum delay, and c represents the speed of light.

6. The beam domain modeling method based on millimeter wave MIMO according to claim 1, characterized in that: The method of S2.4 includes: the average power of the single / double-hop cluster on the kth path is: Among them, the virtual delay of the kth path is r τ represents the delay ratio, σ τ represents the randomly generated delay spread factor, u n represents a random variable that follows a uniform distribution, namely u n ~U(0,1),Z n Obey Gaussian distribution, that is, Z n ~N(0,σ k ), σ k Represents the shaded standard deviation of the one / two-hop clusters.

7. The beam domain modeling method based on millimeter wave MIMO according to claim 1, characterized in that: The method of S3 includes: performing visual area modeling on a planar antenna array to generate visual area positions of single / double-hop clusters in horizontal and vertical directions: in, and are the start index and end index of the antenna array in the horizontal direction of the visible area of ​​the cluster, which obeys the uniform distribution. and are the start index and end index of the antenna array in the vertical direction of the visible area of ​​the cluster, and they obey the uniform distribution, that is, d h and d v Respectively represent the spacing between adjacent UPA antennas in azimuth and elevation.

8. A beam domain modeling system based on millimeter wave MIMO, characterized in that: include: A CIR construction and beam domain transformation module is used to establish a geometric domain CIR system model that characterizes a MIMO channel, and perform beam domain transformation through a unitary matrix to obtain a beam domain CIR system model, wherein the beam domain CIR system model adopts a composite mechanism of single-hop and double-hop propagation, and a scattering environment between a transmitter and a receiver corresponding to the beam domain CIR system model is modeled as a single-hop cluster and a double-hop cluster; a method for establishing a geometric domain CIR system model that characterizes a MIMO channel, and performing beam domain transformation through a unitary matrix to obtain a beam domain CIR system model includes: S1.

1. Establish the geometric domain CIR system model as follows: in, In the formula, h i，j (τ) represents the impulse response between the antenna in the i-th row and j-th column of the transmitter and the receiver, SBC represents a single-hop cluster, DBC represents a double-hop cluster, LoS represents the line-of-sight portion, and K R represents the Rice factor, P k represents the normalized total power of the kth path between the transmitter and the receiver, η SBC and η DBC are the scattering power proportions of the single-hop cluster and the double-hop cluster, represents the impulse response between the transmitter and the receiver, where and Where dh and dv represent the spacing between adjacent antennas in the uniform planar antenna array in azimuth and elevation, respectively. and represent the azimuth angles of the base station side and the user side of the kth path respectively; and denote the elevation angles of the base station side and the user side of the kth path respectively; υ k represents the Doppler frequency shift, where f k =v / λ, λ represents the wavelength, v and α represent the moving speed and moving azimuth of the user side respectively; f c represents the carrier frequency, τ k represents the propagation delay of the kth path, Φ k represents the phase shift of the kth path; S1.2, record middle The response matrix of a uniform planar antenna array is written as: S1.

3. Introducing the transformation matrix Perform beam domain transformation and obtain: in: In the formula, I s and I e are the start index and end index of the antenna in the visible area on the uniform planar antenna array, respectively; The single-hop cluster and double-hop cluster modeling module is used to perform 3D modeling on the parameters of the single-hop cluster and the double-hop cluster in the CIR construction and beam domain transformation module based on the rich scattering characteristics of the millimeter wave channel, and obtain a 3D model of the composite existence of the single-hop cluster and the double-hop cluster, wherein the 3D modeling includes the geometric distribution, angle, delay and power of the single-hop cluster, and the geometric distribution, angle, delay, power and virtual absolute delay of the double-hop cluster; the method for performing 3D modeling on the parameters of the single / double-hop cluster includes: S2.1, based on the single / double-hop cluster to the transmitting end , the distance at the receiving end obeys the exponential distribution to model the geometric distribution of the single / double-hop cluster; S2.2, based on the azimuth angle of the single / double-hop cluster obeying the von Mises distribution and the elevation angle obeying the cosine distribution, the geometric distribution of the single / double-hop cluster is modeled; S2.3, according to the angle parameters of the single / double-hop cluster, the distance vector of the single / double-hop cluster on the transmitter and receiver sides is obtained, and the delay, frequency shift and phase shift of the single / double-hop cluster are modeled based on the distance vector; S2.4, according to the delay obtained in S2.3, the power of the single / double-hop cluster is modeled; The visible area modeling module is used to model the visible areas of single-hop clusters and double-hop clusters on a planar antenna array using the visible area theory, and generate the positions and lengths of the visible areas of the single-hop clusters and double-hop clusters in the horizontal and vertical directions to characterize the non-stationarity of the channel.

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