Transmission channel determination method and transmission method, device, system, equipment, and medium

Abstract

The present disclosure provides a method for determining a transmission channel in a millimeter wave system, a signal transmission method, a device for determining a transmission channel in a millimeter wave system, a signal transmission device, a millimeter wave system, a computer device and a computer-readable medium, wherein the method comprises: constructing a beam space channel model of a millimeter wave system, wherein the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents the channel gain of each sub-beam in the millimeter wave system; obtaining the beam space channel matrix of a legitimate user in the beam space channel model; and using the energy-concentrated sub-beam in the beam space channel matrix of the legitimate user as a transmission channel. In the present disclosure, the sub-beam selection of the beam space channel model retains the energy-concentrated sub-beam, so that the confidentiality capacity of the system is improved, and at the same time, there is no need to sacrifice part of the transmission power for artificial noise.

Description

Technical Field

[0001] The present disclosure relates to the field of communication technology, and in particular to a method for determining a transmission channel in a millimeter wave system, a signal transmission method, a device for determining a transmission channel in a millimeter wave system, a signal transmission device, a millimeter wave system, a computer device, and a computer-readable medium. Background Art

[0002] The explosive growth of wireless communication data traffic has put forward higher requirements on the network capacity of 5G (5th-Generation, fifth-generation mobile communication technology) systems. The millimeter wave frequency range is 30-300GHz, and its abundant available spectrum resources can free the current wireless system from the problem of spectrum congestion and provide the high data traffic required for 5G wireless communication. As the system capacity grows, a large amount of private information is transmitted through the wireless communication system, and the open nature of the wireless channel and the radio characteristics of electromagnetic waves make the design of secure communication more difficult. Physical layer security precoding utilizes the inherent properties of the wireless channel such as time-varying, uniqueness, reciprocity, and signal processing technology to maximize the difference between the legitimate channel and the eavesdropping channel, providing high confidentiality performance for the 5G communication system in the sense of information theory.

[0003] In the existing artificial noise-assisted secure transmission scheme, the millimeter wave communication scenario of multiple input single output (MISO) and single antenna eavesdropper is studied. When the base station only has partial channel state information (CSI) of the eavesdropping channel, the antenna domain millimeter wave channel is converted into a discrete angle domain channel model. The base station sends the information-bearing signal and artificial noise at the same time, precodes and power allocates the information signal and artificial noise at the same time, and uses a noise-corrupted eavesdropping channel. In the discrete angle domain channel model, the association between the eavesdropping channel and the propagation subpath of the legitimate channel can be clearly observed. However, the power allocation factor is derived to minimize the probability of confidentiality interruption under the confidentiality rate limit, and the calculation is complex. Therefore, the existing artificial noise scheme needs to sacrifice part of the transmission power for artificial noise, and the system confidentiality capacity of the wireless communication system is low. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present disclosure provides a method for determining a transmission channel in a millimeter wave system, a signal transmission method, a device for determining a transmission channel in a millimeter wave system, a signal transmission device, a millimeter wave system, a computer device and a computer-readable medium.

[0005] In a first aspect, an embodiment of the present disclosure provides a method for determining a transmission channel in a millimeter wave system, including:

[0006] Constructing a beam space channel model of a millimeter wave system, wherein the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents the channel gain of each sub-beam in the millimeter wave system;

[0007] Obtaining a beam space channel matrix of a legitimate user in the beam space channel model;

[0008] The sub-beam with concentrated energy in the beam space channel matrix of the legal user is used as a transmission channel.

[0009] Preferably, the constructing of the beam space channel model of the millimeter wave system includes:

[0010] Constructing a clustered channel model of the millimeter wave system, wherein the clustered channel model includes an antenna domain channel matrix of a legitimate user and an antenna domain channel matrix of an eavesdropper;

[0011] Calculate the beam space channel matrix of the legal user according to the unitary transformation matrix and the antenna domain channel matrix of the legal user;

[0012] The beam space channel matrix of the eavesdropper is calculated according to the unitary transformation matrix and the antenna domain channel matrix of the eavesdropper, wherein the beam space channel model of the millimeter wave system includes the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper.

[0013] Preferably, the step of using a sub-beam with concentrated energy in a beam space channel matrix of a legitimate user as a transmission channel comprises:

[0014] Normalize the elements of the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper;

[0015] The modulus values ​​of corresponding elements in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper are compared respectively, and the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper is determined as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user.

[0016] Preferably, determining the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user comprises:

[0017] Create a sparse matrix B[b i ];in h Db(i) is the modulus of the corresponding element in the beam space channel matrix of the legal user corresponding to the ith antenna, h Eb (i) is the modulus of the corresponding element in the beam space channel matrix of the eavesdropper corresponding to the ith antenna, N t The number of antennas configured for the base station;

[0018] The sparse matrix b i When it is 1, the corresponding sub-beam is determined to be the sub-beam with concentrated energy in the beam space channel matrix of the legal user.

[0019] In a second aspect, an embodiment of the present disclosure further provides a signal transmission method, including:

[0020] Determine the transmission channel in the millimeter wave system using the method described in the first aspect;

[0021] precoding the information bearing signal;

[0022] The precoded information bearing signal is transmitted using the transmission channel.

[0023] Preferably, in the step of precoding the information bearing signal, maximum ratio transmission is used for the precoding.

[0024] In a third aspect, an embodiment of the present disclosure provides a device for determining a transmission channel in a millimeter wave system, including:

[0025] A construction module, used to construct a beam space channel model of a millimeter wave system, wherein the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents a channel gain of each sub-beam in the millimeter wave system;

[0026] An acquisition module, used to acquire a beam space channel matrix of a legitimate user in the beam space channel model;

[0027] The determination module is used to use the sub-beam with concentrated energy in the beam space channel matrix of the legal user as a transmission channel.

[0028] In a fourth aspect, an embodiment of the present disclosure provides a signal transmission device, including:

[0029] A determination module, configured to determine a transmission channel of the millimeter wave system using the method described in the first aspect;

[0030] A precoding module, used for precoding the information bearing signal;

[0031] The transmission module is used to transmit the precoded information bearing signal by using the transmission channel.

[0032] In a fifth aspect, an embodiment of the present disclosure provides a millimeter wave system, comprising: a device for determining a transmission channel in the millimeter wave system as described in the third aspect, a signal transmission device as described in the fourth aspect, a base station and multiple antennas configured in the base station, wherein the base station transmits millimeter waves through the antenna.

[0033] In a sixth aspect, an embodiment of the present disclosure provides a computer device, including:

[0034] one or more processors;

[0035] a storage device having one or more programs stored thereon;

[0036] When the one or more programs are executed by the one or more processors, the one or more processors implement the method for determining a transmission channel in a millimeter wave system as described in the first aspect and the signal transmission method as described in the second aspect.

[0037] In a seventh aspect, an embodiment of the present disclosure provides a computer-readable medium having a computer program stored thereon, wherein when the program is executed, the method for determining a transmission channel in a millimeter wave system as described in the first aspect and the signal transmission method as described in the second aspect are implemented.

[0038] In the disclosed embodiment, a beam space channel model of a millimeter wave system is constructed, wherein the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents the channel gain of each sub-beam in the millimeter wave system. The beam space channel matrix of the legitimate user in the beam space channel model is obtained, and the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user is used as a transmission channel. By utilizing the sparsity of the beam space channel model, the sub-beam selection of the beam space channel model discards the sub-beam with poor propagation performance in the legitimate channel, retains the sub-beam with concentrated energy, and increases the difference between the legitimate channel and the eavesdropping channel, thereby improving the confidentiality capacity of the system and improving information security, while not requiring the sacrifice of part of the transmission power for artificial noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a flow chart of a method for determining a transmission channel in a millimeter wave system provided by an embodiment of the present disclosure;

[0040] Figure 2 The embodiment of the present disclosure provides Figure 1 An optional implementation of step S101;

[0041] Figure 3 The embodiment of the present disclosure provides Figure 1 An optional implementation of step S103;

[0042] Figure 4 The embodiment of the present disclosure provides Figure 3 An optional implementation of step S303;

[0043] Figure 5 is a schematic diagram of a base station transmitting millimeter waves provided by an embodiment of the present disclosure;

[0044] Figure 6 is a schematic diagram of characterizing the sparsity of the beam space channel model provided by an embodiment of the present disclosure;

[0045] Figure 7 It is a propagation schematic diagram of sub-beam selection of the beam space channel model provided by an embodiment of the present disclosure;

[0046] Figure 8 is a flow chart of a signal transmission method provided by an embodiment of the present disclosure;

[0047] Fig. 9 is a simulation schematic diagram of maximum ratio transmission precoding in the signal transmission method provided by an embodiment of the present disclosure;

[0048] Fig.10 is a structural schematic diagram of a device for determining a transmission channel in a millimeter wave system provided by an embodiment of the present disclosure;

[0049] Fig.11 It is a structural schematic diagram of a signal transmission device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the technical solution of the present disclosure, it is described in detail below with reference to the accompanying drawings.

[0051] Example embodiments will be described more fully below with reference to the accompanying drawings, but the example embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, the purpose of providing these embodiments is to make the present disclosure thorough and complete and to enable those skilled in the art to fully understand the scope of the present disclosure.

[0052] In the absence of conflict, the various embodiments of the present disclosure and the various features therein may be combined with each other.

[0053] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0054] The terms used herein are only used to describe specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It will also be understood that when the terms "comprising" and / or "made of" are used in this specification, the presence of the features, wholes, steps, operations, elements and / or components is specified, but the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof is not excluded.

[0055] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted as having an idealized or overly formal meaning unless explicitly defined as such herein.

[0056] In view of the problem that the existing artificial noise solutions in the prior art need to sacrifice part of the transmission power for artificial noise and the system confidentiality capacity of the wireless communication system is low, the present disclosure proposes a method for determining a transmission channel in a millimeter wave system, a signal transmission method, a device for determining a transmission channel in a millimeter wave system, a signal transmission device, a millimeter wave system, a computer device and a computer readable medium.

[0057] Figure 1 The flowchart of the method for determining the transmission channel in the millimeter wave system provided by the embodiment of the present disclosure is shown. The method for determining the transmission channel in the millimeter wave system can be applied to a device for determining the transmission channel in the millimeter wave system. Figure 1 As shown, the method for determining a transmission channel in a millimeter wave system provided in this embodiment includes the following steps:

[0058] In step S101, a beam space channel model of a millimeter wave system is constructed;

[0059] In step S102, a beam space channel matrix of a legitimate user in a beam space channel model is obtained;

[0060] In step S103, the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user is used as a transmission channel.

[0061] Traditional security precoding schemes, such as Maximum Ratio Transmission (MRT), aim the beam at legitimate users to reduce the receiving power of eavesdroppers. However, their research targets independent and identically distributed Rayleigh fading channels and does not take advantage of the sparse characteristics unique to millimeter wave channels.

[0062] The method for determining the transmission channel in the millimeter wave system provided by the present disclosure constructs a beam space channel model of the millimeter wave system. Among them, the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents the channel gain of each sub-beam in the millimeter wave system. Due to the obvious sparsity of the beam space channel model, it is easier to distinguish between the sub-beams with concentrated energy and other sub-beams, that is, the beam space channel model is more likely to reflect the difference between the sub-beams with better propagation performance and the sub-beams with poor propagation performance. When the sub-beam with concentrated energy is selected to transmit the signal, the power difference between the transmission channel and the eavesdropping channel is large, and it is difficult to eavesdrop on the transmission channel, which improves the system confidentiality capacity of the channel and improves information security, and at the same time does not need to sacrifice part of the transmission power for artificial noise.

[0063] Figure 2 The embodiment of the present disclosure provides Figure 1 An optional implementation of step S101 in . Further, Figure 2 As shown, the construction of the beam space channel model of the millimeter wave system includes:

[0064] Step S201: construct a clustered channel model for a millimeter wave system.

[0065] The clustered channel model includes the antenna domain channel matrix of the legitimate user and the antenna domain channel matrix of the eavesdropper. In the research on secure precoding of millimeter wave wireless communications, due to the high path loss and limited scattering characteristics of millimeter wave transmission, its channel no longer conforms to the traditional Rayleigh fading distribution, and a clustered channel model is usually used to construct the millimeter wave channel.

[0066] Millimeter waves can provide greater bandwidth and system confidentiality capacity for mobile communications. In the embodiment of the present disclosure, a single-user single-eavesdropper model is considered, such as Figure 5 As shown in Figure 1, the base station transmits millimeter waves, and the legitimate users and eavesdroppers receive the millimeter waves transmitted by the base station through different channels. t antennas, and the legitimate user and the eavesdropper are each equipped with one antenna. The channel matrix contains N cl There are N scattering clusters, each of which contains N ray For a millimeter wave system, it is most likely that only one cluster is included, and most of the power is concentrated in a specific cluster. Therefore, in the embodiment of the present disclosure, it is assumed that N cl =1.

[0067] In this step, constructing a clustered channel model of a millimeter wave system includes:

[0068] Create antenna domain channel matrix for legitimate users Create the eavesdropper's antenna domain channel matrix

[0069] The cluster channel model is a single legitimate user and single eavesdropper model. The legitimate user and the eavesdropper are equipped with one antenna. t The number of antennas configured for the base station, the cluster contains N ray propagation paths, θ Dl is the departure angle corresponding to the path gain of the legitimate user, α Dl is the path complex gain of the legitimate user, represents the average power in the i-th cluster, θ El is the departure angle corresponding to the path gain of the eavesdropper, which obeys the Laplace distribution, α El is the complex path gain of the eavesdropper. a(θ Dl ) respectively represent the corresponding departure angle θ il The normalized array response vector, a(θ El ) is the departure angle θ in the lth path El The corresponding array response vector.

[0070]

[0071] in The relationship between antenna spacing and millimeter wave wavelength is:

[0072] Step S202: Calculate the beam space channel matrix of the legal user according to the unitary transformation matrix and the antenna domain channel matrix of the legal user.

[0073] In this step, the beam space channel matrix of the legitimate user is calculated according to the following formula: Db =h D U t ;

[0074] Among them, U t is the unitary transformation matrix, ψ i To leave the angle, a(ψ i ) is the array response vector of each column, d is the antenna spacing, h D is the antenna domain channel matrix of the legitimate user.

[0075] Step S203, calculating the beam space channel matrix of the eavesdropper according to the unitary transformation matrix and the antenna domain channel matrix of the eavesdropper.

[0076] The eavesdropper’s beam space channel matrix is ​​calculated according to the following formula: Eb =h E U t ;

[0077] Among them, U t is the unitary transformation matrix, ψ i To leave the angle, a(ψ i ) is the array response vector of each column, d is the antenna spacing, h E is the antenna domain channel matrix of the eavesdropper.

[0078] It should be noted that the beam space channel model of the millimeter wave system includes the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper. The beam space channel matrix can be obtained by performing a unitary transformation on the antenna domain channel matrix, and the beam space channel matrix presents a sparse characteristic.

[0079] Figure 3 The embodiment of the present disclosure provides Figure 1 An optional implementation of step S103 in . Further, Figure 3 As shown, the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user is used as a transmission channel, including:

[0080] Step S301, normalize the elements in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper.

[0081] Specifically, after the unitary transformation, the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper have sparse properties. Figure 6 As shown in Figure 1, the sparseness of the beam space channel model after the unitary transformation can be clearly reflected. Assume that the base station is equipped with 16 antennas, there are 3 paths in a single cluster, the center angle of the departure angle in the cluster is 0, and the angle expansion σ φ =10°, simulating the legitimate channel and the eavesdropping channel in the antenna domain. The unitary matrix U t The column vector of is:

[0082]

[0083] According to the unitary matrix U t , the antenna domain channel matrix h of the legitimate user D The antenna domain channel matrix h of the eavesdropper E Perform unitary transformations respectively to obtain the beam space channel matrix h of the legitimate user Db The beam space channel matrix h of the eavesdropper Eb After the unitary transformation, the elements in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper are normalized.

[0084] Figure 6 In each sub-graph, the horizontal axis is the channel matrix element index, and the vertical axis is the normalized modulus of the matrix element.D 、h E 、h Db 、h Eb After normalization, we get Figure 6 (a), (b), (c), and (d) in the figure. Figure 6 The antenna domain channel matrix h of the legitimate user in (a) D The modulus values ​​of are relatively close, and more than half of the elements have normalized modulus values ​​greater than 0.5. Figure 6 In (b), only the 1st, 15th, and 16th elements of the beam space channel matrix have a modulus value greater than 0.5, and the remaining elements are relatively small. Similarly, for the eavesdropper, Figure 6 In (d), the modulus of the first and second items of the beam space channel matrix are large, and the sparsity is verified. Here, when there are more base station antennas, the sub-beams are divided narrower, and the channel sparseness is more easily reflected.

[0085] Step S302, respectively compare the module values ​​of the corresponding elements in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper.

[0086] Step S303: determine the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user.

[0087] In step S302-step S303, the beam space channel model shows significant sparsity, and a small number of elements have large modulus values, that is, the power is concentrated on fewer sub-beams. Db The median value is greater than h Eb The sub-beam corresponding to the element of is determined as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user.

[0088] Figure 4 The embodiment of the present disclosure provides Figure 3 An optional implementation of step S303 in . Further, Figure 4 As shown, the step of determining the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user includes:

[0089] Step S401, create a sparse matrix B[b i ].

[0090] in h Db (i) is the modulus of the corresponding element in the beam space channel matrix of the legal user corresponding to the ith antenna, h Eb(i) is the modulus of the corresponding element in the beam space channel matrix of the eavesdropper corresponding to the ith antenna, N t The number of antennas configured for the base station.

[0091] Step S402: convert b in the sparse matrix i When it is 1, the corresponding sub-beam is determined to be the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user.

[0092] In step S401-step S402, compare h Db With h Eb After normalization, the corresponding position elements are retained. Db The elements with larger modulus values ​​are set to 0, and the elements in other positions are set to 0. The sub-beams with larger transmission power in the beam space channel matrix of the legitimate user are retained, and the sub-beams with transmission power inferior to the eavesdropping channel are excluded. Figure 6 As shown, comparison Figure 6 The modulus and value of each vertical axis in (b) Figure 6 The modulus values ​​of the vertical axes in (d) are only those corresponding to the 1st, 14th, 15th, and 16th sub-beams. Db The modulus is greater than h Eb The modulus value, therefore, will correspond to b i is set to 1 and the rest of the elements in the sparse matrix are set to 0. Figure 6 The corresponding sparse matrix created is B = [1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1]. That is, only the 1st, 14th, 15th, and 16th sub-beams of the legal channel are retained for data transmission, and the 12 relatively poor sub-beams of the legal channel are discarded. In other words, the sub-beams with concentrated energy, that is, the sub-beams with larger transmission power in the beam space channel matrix of the legal user are used as transmission channels. Figure 7 The schematic diagram of propagation of sub-beams of the beam space channel model shown is shown, where the shaded sub-beams are sub-beams with concentrated energy in the beam space channel matrix of the selected legitimate user, and data are transmitted on the four sub-beams.

[0093] Figure 8 FIG. 1 is a flow chart of a signal transmission method provided by an embodiment of the present disclosure. The signal transmission method can be applied to a signal transmission device. Figure 8 As shown, the signal transmission method provided in this embodiment includes the following steps:

[0094] Step S501: determine a transmission channel in a millimeter wave system using a method for determining a transmission channel in a millimeter wave system.

[0095] Step S502: pre-code the information bearing signal.

[0096] Precoding technology optimizes the power, rate and even transmission direction of each data stream through a certain preprocessing method, and may eliminate some or all interference between data streams in advance at the transmitter through preprocessing to obtain better performance. Select a precoding vector that can maximize the system confidentiality capacity of the channel, and multiply the information-bearing signal by the precoding vector at the transmitter to reduce the complexity and overhead of the processing required by the receiver.

[0097] In this step, the equivalent legal channel matrix of the transmission channel is calculated according to the following formula: Among them, B is a sparse matrix, is the conjugate transposed matrix of the unitary transformation matrix, h Db is the beam space channel matrix of the legitimate user.

[0098] And the equivalent eavesdropping channel matrix is ​​calculated according to the following formula: Among them, B is a sparse matrix, is the conjugate transposed matrix of the unitary transformation matrix, h Eb is the beam space channel matrix of the eavesdropper.

[0099] The power of the information-carrying signal s satisfies E[|s| 2 ]=1, precoding is used for the transmission channel to ensure communication security, and the precoding vector can be set according to the following formula: To ensure that the signal-to-noise ratio of the legitimate received signal is maximized. is the equivalent legal channel matrix, is the conjugate transposed matrix of the equivalent legal channel matrix. Then the signal transmitted by the base station is x=fs, which is the precoded information-bearing signal.

[0100] Step S503: transmit the precoded information bearing signal using a transmission channel.

[0101] Furthermore, in the step of precoding the information bearing signal (ie, step S502), maximum ratio transmission is used for precoding.

[0102] MRT precoding, also known as matched filter precoding, is the simplest and easiest to implement precoding algorithm, which is achieved by maximizing the received signal-to-noise ratio. MRT precoding maximizes the signal gain of the receiving end user so that the best spectrum efficiency and the best signal transmission quality can be obtained with the lowest complexity.

[0103] In the disclosed embodiment, a sub-beam with concentrated energy in the beam space channel matrix of a legitimate user is selected, that is, a sub-beam with larger power is selected, and inferior sub-beams are discarded, thereby obtaining a transmission channel suitable for signal transmission. The difference between the transmission channel and the eavesdropping channel is increased, thereby improving the system confidentiality capacity of the channel and improving information security, while at the same time, there is no need to sacrifice part of the transmission power for artificial noise. Further, for the transmission channel after the sub-beam selection, maximum ratio transmission precoding is performed to maximize the overall signal-to-noise ratio, thereby improving the system confidentiality capacity compared to the traditional maximum ratio transmission. Therefore, the precoding method of the disclosed embodiment does not need to sacrifice additional transmission power for artificial noise, and can improve the system confidentiality capacity, so that the system performance is optimized.

[0104] Specifically, in the simulation verification process, calculating the signal-to-noise ratio of the legitimate user's received signal and the signal-to-noise ratio of the eavesdropper's received signal includes the following steps. The embodiment of the present disclosure maximizes the signal-to-noise ratio of the legitimate user's received signal through a preset precoding vector f, thereby realizing maximum ratio transmission precoding.

[0105] The legitimate party's received signal and the eavesdropper's received signal are calculated according to the following formula: Among them, y D The received signal y of the legitimate party E is the eavesdropper's received signal n D and n E is additive white Gaussian noise and fs is the preset base station transmission signal,

[0106] The signal-to-noise ratio of the legitimate user's received signal and the signal-to-noise ratio of the eavesdropper's received signal are calculated according to the following formulas:

[0107]

[0108] Among them, σ n 2 is the power of the additive white Gaussian noise of the received signal, is the equivalent legal channel matrix, is the conjugate transposed matrix of the equivalent legal channel matrix, is the equivalent eavesdropping channel matrix, ξ D is the signal-to-noise ratio of the received signal of the legitimate user, ξ E is the signal-to-noise ratio of the eavesdropper's received signal.

[0109] Finally, the system confidentiality capacity is the legal channel capacity C D and the eavesdropping channel capacity C E If C D Greater than C E, then the system confidentiality capacity is calculated according to the following formula: C s =[C D -C E ] + =[log2(1+ξ D )-log2(1+ξ E )]; where ξ D is the signal-to-noise ratio of the received signal of the legitimate user, ξ E is the signal-to-noise ratio of the eavesdropper’s received signal. In the present disclosure, C D With C E The difference is thus increased, thus improving the system's confidentiality capacity.

[0110] In addition, it should be noted that, compared with the traditional maximum ratio transmission scheme, the system confidentiality capacity in the present disclosure is also improved. Fig. 9 As shown, in the single-user single-eavesdropper millimeter wave communication scenario, the maximum ratio transmission system confidentiality capacity simulation analysis is carried out on the transmission channel after sub-beam selection, and its advantages compared with the traditional maximum ratio transmission scheme are compared. Fig. 9 The vertical axis is the confidentiality rate, that is, the confidentiality capacity of the system, and the horizontal axis is the noise power. Assume that the base station is equipped with 16 transmitting antennas, and the legitimate user and the eavesdropper are equipped with a single antenna. The millimeter wave clustered channel model has a single cluster with 3 propagation paths in the cluster, and its path gain α l Independent and identically distributed and α l ~CN(0,1),l=1,2,3,azimuthθ l It follows a Laplace distribution with a mean of 0 and a standard deviation of 10°, and the information-carrying signal s satisfies E[|s| 2 ]=1, the power is 0dBm, and additive Gaussian white noise of different powers is used for simulation.

[0111] from Fig. 9 It can be seen that compared with the system confidentiality capacity of the traditional maximum ratio transmission scheme ( Fig. 9 The upper curve in the figure), the confidentiality capacity of the system in the present disclosure ( Fig. 9 The curve below in the figure is improved. Because the sub-beam selection of the beam space channel model discards the beam with poor propagation performance in the legitimate channel and retains the better sub-beam, the difference between the legitimate channel and the eavesdropping channel increases, and the security is improved. At the same time, the system confidentiality capacity decreases with the increase of additive white Gaussian noise. When the noise power is close to the information-bearing signal, the impact of noise on the system confidentiality capacity increases. At this time, the system confidentiality capacity of the present disclosure is similar to that of the traditional maximum ratio transmission.

[0112] Fig.10 A schematic diagram of the structure of a device for determining a transmission channel in a millimeter wave system provided by an embodiment of the present disclosure is shown. Figure 1The same technical concept as the corresponding embodiments, such as Fig.10 As shown, the device for determining the transmission channel in the millimeter wave system provided by the embodiment of the present disclosure includes the following modules.

[0113] A construction module 11 is used to construct a beam space channel model of the millimeter wave system, wherein the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents the channel gain of each sub-beam in the millimeter wave system;

[0114] An acquisition module 12 is used to acquire a beam space channel matrix of a legitimate user in the beam space channel model;

[0115] The determination module 13 is configured to use a sub-beam with concentrated energy in the beam space channel matrix of the legal user as a transmission channel.

[0116] The building block 11 is specifically used for:

[0117] Constructing a clustered channel model of the millimeter wave system, wherein the clustered channel model includes an antenna domain channel matrix of a legitimate user and an antenna domain channel matrix of an eavesdropper;

[0118] Calculate the beam space channel matrix of the legal user according to the unitary transformation matrix and the antenna domain channel matrix of the legal user;

[0119] The beam space channel matrix of the eavesdropper is calculated according to the unitary transformation matrix and the antenna domain channel matrix of the eavesdropper, wherein the beam space channel model of the millimeter wave system includes the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper.

[0120] In some embodiments, the determining module 13 includes:

[0121] A processing submodule, used for normalizing each element in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper;

[0122] A comparison submodule, used for comparing the modulus values ​​of corresponding elements in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper respectively;

[0123] The determination submodule is used to determine the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user.

[0124] In some embodiments, the determining submodule is specifically used to:

[0125] Create a sparse matrix B[b i ];in h Db (i) is the modulus of the corresponding element in the beam space channel matrix of the legal user corresponding to the ith antenna, h Eb (i) is the modulus of the corresponding element in the beam space channel matrix of the eavesdropper corresponding to the ith antenna, N t The number of antennas configured for the base station;

[0126] The sparse matrix b i When it is 1, the corresponding sub-beam is determined to be the sub-beam with concentrated energy in the beam space channel matrix of the legal user.

[0127] Fig.11 A schematic diagram of the structure of a signal transmission device provided by an embodiment of the present disclosure is shown. Figure 8 The same technical concept as the corresponding embodiments, such as Fig.11 As shown, the signal transmission device provided by the embodiment of the present disclosure includes the following modules:

[0128] A determination module 21, configured to determine a transmission channel in a millimeter wave system by using the method for determining a transmission channel in a millimeter wave system;

[0129] A precoding module 22, configured to precode the information bearing signal;

[0130] The transmission module 23 is configured to transmit the precoded information bearing signal by using the transmission channel.

[0131] In some embodiments, in the precoding module 22, maximum ratio transmission is used to perform the precoding.

[0132] The embodiments of the present disclosure also provide a millimeter wave system, comprising: a device for determining a transmission channel in the millimeter wave system as described in the aforementioned embodiments, a signal transmission device as described in the aforementioned embodiments, a base station, and multiple antennas configured in the base station, wherein the base station transmits millimeter waves through the antennas.

[0133] An embodiment of the present disclosure also provides a computer device, including: one or more processors; a storage device on which one or more programs are stored; when the one or more programs are executed by the one or more processors, the one or more processors implement the method for determining the transmission channel in the millimeter wave system provided in the aforementioned embodiments and the signal transmission method provided in the aforementioned embodiments.

[0134] An embodiment of the present disclosure further provides a computer-readable medium having a computer program stored thereon, wherein when the program is executed, the method for determining a transmission channel in a millimeter wave system and the signal transmission method provided in the aforementioned embodiments are implemented.

[0135] It will be appreciated by those skilled in the art that all or some of the steps in the method disclosed above, the functional modules / units in the device may be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware implementations, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed by several physical components in cooperation. Some physical components or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or non-transitory medium) and a communication medium (or temporary medium). As known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, it is well known to those of ordinary skill in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0136] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and should be interpreted only in a general illustrative sense and not for limiting purposes. In some instances, it will be apparent to those skilled in the art that, unless otherwise expressly stated, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A method for determining a transmission channel in a millimeter wave system, comprising: Constructing a beam space channel model of a millimeter wave system, wherein the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents the channel gain of each sub-beam in the millimeter wave system; the beam space channel model of the millimeter wave system includes a beam space channel matrix of a legitimate user and a beam space channel matrix of an eavesdropper; Acquire the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper in the beam space channel model; Using the sub-beam with concentrated energy in the beam space channel matrix of the legal user as a transmission channel; The using the sub-beam with concentrated energy in the beam space channel matrix of the legal user as a transmission channel includes: Normalizing each element in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper; The modulus values ​​of corresponding elements in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper are compared respectively, and the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper is determined as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user.

2. The method of claim 1, wherein: The method of constructing a beam space channel model of a millimeter wave system includes: Constructing a clustered channel model of the millimeter wave system, wherein the clustered channel model includes an antenna domain channel matrix of a legitimate user and an antenna domain channel matrix of an eavesdropper; Calculate the beam space channel matrix of the legal user according to the unitary transformation matrix and the antenna domain channel matrix of the legal user; The beam space channel matrix of the eavesdropper is calculated according to the unitary transformation matrix and the antenna domain channel matrix of the eavesdropper.

3. The method according to claim 1, wherein: The step of determining the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user, comprises: Create a sparse matrix B[b i ];in h Db (i) is the modulus of the corresponding element in the beam space channel matrix of the legal user corresponding to the ith antenna, h Eb (i) is the modulus of the corresponding element in the beam space channel matrix of the eavesdropper corresponding to the ith antenna, N t The number of antennas configured for the base station; The sparse matrix b i When it is 1, the corresponding sub-beam is determined to be the sub-beam with concentrated energy in the beam space channel matrix of the legal user.

4. A signal transmission method, comprising: Determine a transmission channel in a millimeter wave system using the method described in any one of claims 1 to 3; precoding the information bearing signal; The precoded information bearing signal is transmitted using the transmission channel.

5. The signal transmission method according to claim 4, wherein: In the step of precoding the information bearing signal, the precoding is performed using maximum ratio transmission.

6. A device for determining a transmission channel in a millimeter wave system, comprising: A construction module, used to construct a beam space channel model of a millimeter wave system, wherein the beam space channel model uses a sparse matrix to represent the sub-beams in the millimeter wave system, and each element in the matrix represents the channel gain of each sub-beam in the millimeter wave system; the beam space channel model of the millimeter wave system includes a beam space channel matrix of a legitimate user and a beam space channel matrix of an eavesdropper; An acquisition module, used to acquire the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper in the beam space channel model; A determination module is used to use the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user as a transmission channel; wherein each element in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper is normalized; the modulus values ​​of the corresponding elements in the beam space channel matrix of the legitimate user and the beam space channel matrix of the eavesdropper are compared respectively, and the sub-beam corresponding to the element whose modulus value in the beam space channel matrix of the legitimate user is larger than the modulus value in the beam space channel matrix of the eavesdropper is determined as the sub-beam with concentrated energy in the beam space channel matrix of the legitimate user.

7. A signal transmission device, comprising: A determination module, configured to determine a transmission channel in a millimeter wave system using the method described in any one of claims 1 to 3; A precoding module, used for precoding the information bearing signal; The transmission module is used to transmit the precoded information bearing signal by using the transmission channel.

8. A millimeter wave system comprising: The device for determining transmission channels in a millimeter wave system as described in claim 6, the signal transmission device as described in claim 7, a base station and multiple antennas configured in the base station, wherein the base station transmits millimeter waves through the antennas.

9. A computer device comprising: one or more processors; a storage device having one or more programs stored thereon; When the one or more programs are executed by the one or more processors, the one or more processors implement the method for determining a transmission channel in a millimeter wave system as described in any one of claims 1 to 3 or the signal transmission method as described in any one of claims 4 to 5.

10. A computer readable medium having a computer program stored thereon, wherein: When the program is executed, the method for determining a transmission channel in a millimeter wave system according to any one of claims 1 to 3 or the signal transmission method according to any one of claims 4 to 5 is implemented.

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