Antenna system precoding method, device, equipment, storage medium and product

Abstract

The invention discloses an antenna system precoding method, device and equipment, a storage medium and a product, and the method comprises the steps: obtaining an initial uplink channel matrix, an access point side calibration coefficient matrix and a user equipment side calibration coefficient matrix, determining a corrected and compensated uplink channel according to the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix; and determining a calibration coefficient error statistical characteristic parameter, and obtaining a target precoding matrix according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated downlink channel in combination with a set precoding algorithm. According to the antenna system precoding method disclosed by the invention, the uncertain influence of the calibration coefficient error is eliminated by introducing the calibration coefficient error statistical characteristic parameter, so that the performance of the precoding method cannot be obviously reduced even under the condition of relatively large calibration time delay.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to an antenna system precoding method, device, equipment, storage medium and product. Background Art

[0002] In a CF-mMIMO system, the access point AP is connected to the central processing unit CPU via a wire, and the CPU needs to use the downlink channel information to calculate the precoding matrix. In order to avoid downlink channel feedback, it is usually assumed that the system works in TDD (Time-division Duplex) mode, using the reciprocity of the air interface uplink and downlink channels to obtain the downlink channel based on the uplink channel.

[0003] However, ideal channel reciprocity is limited to the air interface channel between the access point AP antenna and the user equipment UE antenna. Generally speaking, the AP's transmit chain and receive chain use different RF circuits, resulting in inconsistent uplink and downlink channel gain coefficients, making the channels no longer reciprocal. In order to restore the reciprocity between the uplink and downlink channels, a calibration scheme can be used to compensate for the gain difference between the uplink and downlink channels. However, due to distributed deployment, different APs often use independent oscillators, and due to changes in the environment (such as temperature, humidity, etc.), the phase drift between independent oscillators presents a time-varying characteristic, which ultimately causes the gain difference between the uplink and downlink channels to change over time.

[0004] In the air interface calibration scheme, calibration reference signals are sent between APs or between APs and UEs. AP or UE estimates the uplink and downlink channels from the calibration reference signals and performs channel feedback. Finally, the AP derives the gain difference between the uplink and downlink channels through channel feedback and channel estimation. This gain difference is called the calibration coefficient. Obviously, in the air interface calibration scheme, the calibration coefficient reflects the gain difference between the uplink and downlink channels corresponding to the time when the calibration reference signal is sent. In the actual system, there is generally a delay of several milliseconds between the time when the calibration reference signal is sent and the time when the downlink data is transmitted. This delay is called the calibration delay. For low-cost deployed APs, a calibration delay of several milliseconds is enough to cause a large error in the calibration coefficient. Traditional precoding methods require the use of accurate downlink channel information to eliminate interference between multiple UEs. In this case, the reciprocity of the uplink and downlink channels is difficult to guarantee, and the performance of precoding will be greatly affected. Summary of the invention

[0005] The present invention provides an antenna system precoding method, device, equipment, storage medium and product to overcome the influence of calibration delay on precoding performance.

[0006] According to one aspect of the present invention, there is provided an antenna system precoding method, comprising:

[0007] Acquire an initial uplink channel matrix, an access point side calibration coefficient matrix, and a user equipment side calibration coefficient matrix, and determine a corrected and compensated uplink channel according to the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix;

[0008] A calibration coefficient error statistical characteristic parameter is determined, and a target precoding matrix is ​​obtained according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with a set precoding algorithm.

[0009] Further, the setting precoding algorithm includes a zero-forcing precoding algorithm, and according to the calibration coefficient error statistical characteristic parameter and the uplink channel after correction and compensation, and in combination with the setting precoding algorithm, a target precoding matrix is ​​obtained, including:

[0010] The norm of the difference between the product of the precoding matrix and the downlink channel matrix and the unit matrix is ​​used as the first target norm; wherein the downlink channel matrix is ​​related to the corrected and compensated uplink channel;

[0011] According to the zero-forcing precoding algorithm, taking the expectation of the first target norm with respect to the calibration coefficient error statistical characteristic parameter as a first target expectation function;

[0012] A precoding matrix that minimizes the first objective expectation function is determined as the target precoding matrix.

[0013] Furthermore, after obtaining the target precoding matrix, the method further includes:

[0014] A power constraint factor is determined, and a product of the power constraint factor and the target precoding matrix is ​​determined as an actual precoding matrix.

[0015] Furthermore, the power constraint factor is determined according to a maximum transmit signal power of the signal transmitting end and an initial transmit signal power of the signal transmitting end without precoding.

[0016] Further, the setting precoding algorithm includes a Wiener precoding algorithm, and according to the calibration coefficient error statistical characteristic parameter and the uplink channel after correction and compensation, and in combination with the setting precoding algorithm, a target precoding matrix is ​​obtained, including:

[0017] The product of the received signal and the gain factor is used as a first product, and the norm of the difference between the transmitted signal and the first product is used as a second target norm; wherein the received signal is related to the corrected and compensated uplink channel;

[0018] According to the Wiener precoding algorithm, taking the expectation of the second target norm with respect to the calibration coefficient error statistical characteristic parameter, the transmission signal and the receiving end noise as a second target expectation function;

[0019] A precoding matrix that minimizes the second objective expectation function and satisfies a power constraint condition is determined as the target precoding matrix.

[0020] Further, the setting precoding algorithm includes a minimum mean square error precoding algorithm, and according to the calibration coefficient error statistical characteristic parameter and the uplink channel after correction and compensation, and in combination with the setting precoding algorithm, a target precoding matrix is ​​obtained, including:

[0021] Taking the norm of the difference between the transmitted signal and the received signal as the third target norm; wherein the received signal is related to the corrected and compensated uplink channel;

[0022] According to the minimum mean square error precoding algorithm, taking the expectation of the third target norm with respect to the calibration coefficient error statistical characteristic parameter, the transmission signal and the receiving end noise as a third target expectation function;

[0023] A precoding matrix that minimizes the third objective expectation function and satisfies a power constraint condition is determined as the target precoding matrix.

[0024] According to another aspect of the present invention, there is provided an antenna system precoding device, comprising:

[0025] A module for determining a corrected uplink channel, configured to obtain an initial uplink channel matrix, an access point side calibration coefficient matrix, and a user equipment side calibration coefficient matrix, and determine a corrected uplink channel according to the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix;

[0026] The target precoding matrix determination module is used to determine the calibration coefficient error statistical characteristic parameter, and obtain the target precoding matrix according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with the set precoding algorithm.

[0027] Optionally, the set precoding algorithm includes a zero-forcing precoding algorithm, and the target precoding matrix determination module is further used to:

[0028] The norm of the difference between the product of the precoding matrix and the downlink channel matrix and the unit matrix is ​​used as the first target norm; wherein the downlink channel matrix is ​​related to the corrected and compensated uplink channel;

[0029] According to the zero-forcing precoding algorithm, taking the expectation of the first target norm with respect to the calibration coefficient error statistical characteristic parameter as a first target expectation function;

[0030] A precoding matrix that minimizes the first objective expectation function is determined as the target precoding matrix.

[0031] Optionally, the device further includes an actual precoding matrix determination module, configured to determine a power constraint factor, and determine the product of the power constraint factor and the target precoding matrix as the actual precoding matrix.

[0032] Optionally, the power constraint factor is determined according to a maximum transmitted signal power of a signal transmitting end and an initial transmitted signal power of the signal transmitting end without precoding.

[0033] Optionally, the set precoding algorithm includes a Wiener precoding algorithm, and the target precoding matrix determination module is further used to:

[0034] The product of the received signal and the gain factor is used as a first product, and the norm of the difference between the transmitted signal and the first product is used as a second target norm; wherein the received signal is related to the corrected and compensated uplink channel;

[0035] According to the Wiener precoding algorithm, taking the expectation of the second target norm with respect to the calibration coefficient error statistical characteristic parameter, the transmission signal and the receiving end noise as a second target expectation function;

[0036] A precoding matrix that minimizes the second objective expectation function and satisfies a power constraint condition is determined as the target precoding matrix.

[0037] Optionally, the set precoding algorithm includes a minimum mean square error precoding algorithm, and the target precoding matrix determination module is further used to:

[0038] Taking the norm of the difference between the transmitted signal and the received signal as the third target norm; wherein the received signal is related to the corrected and compensated uplink channel;

[0039] According to the minimum mean square error precoding algorithm, taking the expectation of the third target norm with respect to the calibration coefficient error statistical characteristic parameter, the transmission signal and the receiving end noise as a third target expectation function;

[0040] A precoding matrix that minimizes the third objective expectation function and satisfies a power constraint condition is determined as the target precoding matrix.

[0041] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0042] at least one processor; and

[0043] a memory communicatively connected to the at least one processor; wherein,

[0044] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the antenna system precoding method described in any embodiment of the present invention.

[0045] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the antenna system precoding method described in any embodiment of the present invention when executed.

[0046] According to another aspect of the present invention, a computer program product is provided. The computer program product includes a computer program / instruction. When the computer program / instruction is executed by a processor, the steps of the antenna system precoding method according to any embodiment of the present invention are implemented.

[0047] The antenna system precoding method disclosed in the present invention first obtains the initial uplink channel matrix, the calibration coefficient matrix on the access point side and the calibration coefficient matrix on the user equipment side, and determines the uplink channel after correction and compensation according to the calibration coefficient matrix on the access point side and the calibration coefficient matrix on the user equipment side; then determines the calibration coefficient error statistical characteristic parameters, and obtains the target precoding matrix according to the calibration coefficient error statistical characteristic parameters and the uplink channel after correction and compensation, and in combination with the setting of the precoding algorithm. The antenna system precoding method disclosed in the present invention eliminates the uncertainty influence of the calibration coefficient error by introducing the calibration coefficient error statistical characteristic parameters, so that even in the case of a large calibration delay, the precoding method will not have obvious performance degradation.

[0048] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0050] Figure 1 is a flowchart of an antenna system precoding method provided according to Embodiment 1 of the present invention;

[0051] Figure 2 is a schematic diagram of a non-cellular large-scale antenna system provided according to Embodiment 1 of the present invention;

[0052] Figure 3 is a structural schematic diagram of an antenna system precoding device provided according to Embodiment 2 of the present invention;

[0053] Figure 4 It is a structural diagram of an electronic device for implementing the antenna system precoding method of embodiment 3 of the present invention. DETAILED DESCRIPTION

[0054] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0055] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0056] Embodiment 1

[0057] Figure 1 This is a flowchart of an antenna system precoding method provided in Embodiment 1 of the present invention. This embodiment is applicable to the case where precoding is performed in an antenna system. The method can be performed by an antenna system precoding device. The antenna system precoding device can be implemented in the form of hardware and / or software. The antenna system precoding device can be configured in an electronic device. Figure 1 As shown, the method includes:

[0058] S110, obtaining an initial uplink channel matrix, an access point side calibration coefficient matrix, and a user equipment side calibration coefficient matrix, and determining a corrected and compensated uplink channel according to the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix.

[0059] In this embodiment, Cell-free massive MIMO (CF-mMIMO) is a wireless communication technology that aims to eliminate inter-cell interference through the deployment of a large number of distributed small base stations and the introduction of a collaborative mechanism, using a user-centric network architecture, thereby significantly improving network capacity and coverage. Figure 2 It is a schematic diagram of a non-cellular large-scale antenna system provided by an embodiment of the present invention. As shown in the figure, the non-cellular large-scale antenna system is composed of a central processing unit (CPU), multiple access points (APs) and multiple user equipments (UEs). The access point AP is connected to the central processing unit CPU through a wire, and the access point AP and the user equipment UE send and receive signals through a wireless channel.

[0060] Let M and K represent the number of antennas on the AP side and UE side respectively, and define c m，tx，ap and c m，rx，ap They represent the gain coefficient of the transmitting RF circuit and the receiving RF circuit of the mth antenna on the AP side, respectively. k，tx，ue and c k，rx，ue denote the gain coefficient of the transmitting RF circuit and the receiving RF circuit of the kth antenna on the UE side, respectively. Then, the downlink channel h between the mth antenna on the AP side and the kth antenna on the UE side is mk，d With the uplink channel h mk，u They are:

[0061] h mk，d =c k，rx，ue ·h mk ·c m，tx，ap

[0062] h mk，u =c m，rx，ap ·h mk ·c k，tx，ue

[0063] Among them, h mk is the air interface channel between the mth antenna on the AP side and the kth antenna on the UE side. The above relationship is written in matrix form:

[0064]

[0065]

[0066] Define the calibration matrix as:

[0067]

[0068]

[0069] Define the calibration vector as:

[0070] c ap =diag(Cap )

[0071] c ue =diag(C ue )

[0072]

[0073]

[0074] According to the above relationship, the following equation can be obtained:

[0075]

[0076] Among them, H u That is the initial uplink channel matrix, C ap and C ue They are the calibration coefficient matrix on the access point side (AP side) and the calibration coefficient matrix on the user equipment side (UE side), and the uplink channel after correction and compensation can be determined according to the calibration coefficient matrix on the access point side and the calibration coefficient matrix on the user equipment side:

[0077]

[0078] S120, determining calibration coefficient error statistical characteristic parameters, and obtaining a target precoding matrix according to the calibration coefficient error statistical characteristic parameters and the corrected and compensated uplink channel in combination with a set precoding algorithm.

[0079] Under ideal channel reciprocity conditions, the initial uplink channel matrix H is obtained. u And the calibration coefficient matrix C on the AP side and the UE side ap and C ue After that, the CPU can calculate the downlink channel matrix under ideal conditions. And precoding is performed. However, due to changes in the environment (such as temperature, humidity, etc.), the phase drift between independent oscillators presents a time-varying characteristic. Generally speaking, the phase drift of the oscillator causes the phase of the true calibration coefficient to jitter around the estimated calibration coefficient phase, while the amplitude of the true calibration coefficient changes very little. Therefore, after considering the calibration delay and the time-varying characteristics of the calibration coefficient, the relationship between the uplink and downlink channels can be modeled as follows:

[0080]

[0081] in, is the uplink channel after correction and compensation, E ue and E ap are the calibration coefficient error matrices at the UE side and the AP side, respectively, and the corresponding calibration coefficient error vectors are defined as follows:

[0082] e ap =diag(E ap )

[0083] e ue =diag(E ue )

[0084]

[0085]

[0086] Among them, θ m，ap , m = 1, ..., M and θ k，ue , k=1,...,K respectively obey some independent and identical distribution symmetric about 0°, such as uniform distribution or Gaussian truncated distribution. Therefore, we can record as well as e ap and e ue That is, the statistical characteristic parameter of the calibration coefficient error.

[0087] In this embodiment, after the calibration coefficient error statistical characteristic parameter is determined, the target precoding matrix can be calculated based on the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with the set precoding algorithm.

[0088] Optionally, the precoding algorithm is set to include a zero-forcing precoding algorithm. According to the calibration coefficient error statistical characteristic parameters and the uplink channel after correction and compensation, and in combination with the setting of the precoding algorithm, a method for obtaining a target precoding matrix may be: taking the norm of the difference between the product of the precoding matrix and the downlink channel matrix and the unit matrix as a first target norm; wherein the downlink channel matrix is ​​related to the uplink channel after correction and compensation; according to the zero-forcing precoding algorithm, taking the expectation of the first target norm with respect to the calibration coefficient error statistical characteristic parameters as a first target expectation function; and determining the precoding matrix that makes the first target expectation function take the minimum value as the target precoding matrix.

[0089] Specifically, Zero Forcing (ZF) is a linear precoding technology whose core principle is to separate the transmitted data stream through beamforming so that a unit response is generated in the desired direction and a zero response is generated in the undesired direction. When using RZF for precoding, the target precoding matrix can be obtained by solving the following optimization problem:

[0090]

[0091] Where W is the precoding matrix, W RZF is the optimal solution of the precoding matrix W (i.e., the target precoding matrix), I is the unit matrix, It means to find the expectation of the random variable x. is the first target norm, is the first objective expectation function, which represents the first objective norm with respect to the calibration coefficient error statistical characteristic parameter e ap and e ue expectations. Therefore, the downlink channel matrix H d The uplink channel after correction and compensation Related.

[0092] Target precoding matrix W RZF For order The value of the precoding matrix W that takes the minimum value is to solve W RZF ,definition Then we have:

[0093]

[0094] Among them, Δ is a quantity independent of W.

[0095] The conjugate gradient of J(W) with respect to W is:

[0096]

[0097] According to the first-order optimality condition, we can get:

[0098]

[0099] in represents the pseudo-inverse operation, and there is

[0100]

[0101]

[0102] where ⊙ is the Hadamard product, and

[0103] E=(1-|e ap | 2 )·I+|e ap | 2 1 M×M

[0104] Substituting into

[0105]

[0106] in, for The conjugate matrix of for The transposed matrix of .

[0107] Based on the above formula According to the calibration coefficient error statistical characteristic parameter e ap 、e ue And the corrected uplink channel Calculate the target precoding matrix W RZF .

[0108] Furthermore, after obtaining the target precoding matrix, it is also possible to: determine a power constraint factor, and determine the product of the power constraint factor and the target precoding matrix as the actual precoding matrix.

[0109] Preferably, the power constraint factor is determined according to the maximum transmit signal power of the signal transmitting end and the initial transmit signal power of the signal transmitting end without precoding.

[0110] Specifically, considering the transmit power constraint on the AP side, let P max represents the maximum signal power sent by the signal transmitter, let represents the initial transmission signal power of the signal transmitter without precoding, then in is the downlink data symbol vector sent by the AP side, and Can be found at W RZF The power constraint factor β is introduced into the expression RZF :

[0111]

[0112] Then the actual precoding matrix can be expressed as:

[0113]

[0114] Optionally, the precoding algorithm is set to include the Wiener precoding algorithm, and according to the calibration coefficient error statistical characteristic parameters and the uplink channel after correction and compensation, and in combination with the setting of the precoding algorithm, a method for obtaining the target precoding matrix may be: taking the product of the received signal and the gain factor as the first product, and taking the norm of the difference between the transmitted signal and the first product as the second target norm; wherein the received signal is related to the uplink channel after correction and compensation; according to the Wiener precoding algorithm, taking the expectation of the second target norm with respect to the calibration coefficient error statistical characteristic parameters, the transmitted signal and the receiving end noise as the second target expectation function; and determining the precoding matrix that minimizes the second target expectation function and satisfies the power constraint as the target precoding matrix.

[0115] Specifically, Wiener Filter (WF) is a linear precoding technology, the basic principle of which is to design a filter by minimizing the mean square error between the received signal and the original signal. Assume that the downlink data symbol vector sent by the AP side is Then the data symbol vector received by the UE side is Where n is additive Gaussian white noise, and as well as in Indicates the initial transmission signal power of the signal transmitter without precoding. is the noise power. Considering the automatic gain control on the UE side and the power constraint on the AP side, let P max Indicates the maximum signal power of the signal transmitter.

[0116] When using WF for precoding, the target precoding matrix can be obtained by solving the following optimization problem:

[0117]

[0118] Among them, W RW is the optimal solution of the precoding matrix W (i.e., the target precoding matrix), β -1 is the gain factor on the UE side, is the first product, is the second objective norm, is the second objective expectation function, which represents the second objective norm with respect to the calibration coefficient error statistical characteristic parameter e ap and e ue , the expectation of the transmitted signal s and the receiving end noise n. is the power constraint. W RW and β RW For order The values ​​of the precoding matrix W and the gain factor β that take the minimum value.

[0119] According to the Lagrange multiplier method, we can get the following results:

[0120]

[0121]

[0122]

[0123] where ⊙ is the Hadamard product, and

[0124] E=(1-|e ap | 2 )·I+|e ap | 2 1 M×M

[0125] Expression-based According to the calibration coefficient error statistical characteristic parameter e ap 、e ueAnd the corrected uplink channel Calculate the target precoding matrix W RW .

[0126] Optionally, the precoding algorithm is set to include a minimum mean square error precoding algorithm. According to the calibration coefficient error statistical characteristic parameters and the uplink channel after correction and compensation, and in combination with the set precoding algorithm, a method for obtaining a target precoding matrix may be: taking the norm of the difference between the transmitted signal and the received signal as a third target norm; wherein the received signal is related to the uplink channel after correction and compensation; according to the minimum mean square error precoding algorithm, taking the expectation of the third target norm with respect to the calibration coefficient error statistical characteristic parameters, the transmitted signal and the receiving end noise as a third target expectation function; and determining the precoding matrix that minimizes the third target expectation function and satisfies the power constraint as the target precoding matrix.

[0127] Specifically, minimum mean-square error (MMSE) precoding is a signal processing technology that aims to minimize the mean square error between the received signal and the expected signal, thereby achieving the best signal-to-noise ratio and bit error rate performance. Assume that the downlink data symbol vector sent by the AP side is Then the data symbol vector received by the UE side is Where n is additive Gaussian white noise, and as well as in Indicates the initial transmission signal power of the signal transmitter without precoding. is the noise power. Considering the AP side transmitter power constraint, let P max Indicates the maximum signal power of the signal transmitter.

[0128] When MMSE is used for precoding, the target precoding matrix can be obtained by solving the following optimization problem:

[0129]

[0130] Among them, W RMMSE is the optimal solution of the precoding matrix W (i.e., the target precoding matrix), is the third objective norm, is the third objective expectation function, which represents the third objective norm with respect to the calibration coefficient error statistical characteristic parameter e ap and e ue , the expectation of the transmitted signal s and the receiving end noise n. is the power constraint. W RMMSE For order The value of the precoding matrix W that takes the minimum value.

[0131] By introducing the Lagrange multiplier λ ≥ 0, we can obtain

[0132]

[0133] Where W RMMSE is a function of λ. According to the relaxed complementarity condition, when

[0134]

[0135] When W RMMSE With no power constraint factor β RZF W RZF have the same form, namely

[0136]

[0137] Otherwise, the optimal solution of λ needs to be obtained by solving the following equation:

[0138]

[0139] The above formula is equivalent to

[0140]

[0141] in, DΛD H yes The eigenvalue decomposition of is, Λ is the eigenvalue matrix. Let [X] mm represents the mth diagonal element of X, the above formula can be simplified to

[0142]

[0143] Among them, the left side of the equal sign in the above formula is monotonically decreasing with respect to λ, and λ can be searched by bisection to determine the value of λ.

[0144] After determining the value of λ, based on the expression According to the calibration coefficient error statistical characteristic parameter e ap 、e ue And the corrected uplink channel Calculate the target precoding matrix W RMMSE .

[0145] The antenna system precoding method disclosed in the present invention first obtains the initial uplink channel matrix, the calibration coefficient matrix on the access point side and the calibration coefficient matrix on the user equipment side, and determines the uplink channel after correction and compensation according to the calibration coefficient matrix on the access point side and the calibration coefficient matrix on the user equipment side; then determines the calibration coefficient error statistical characteristic parameters, and obtains the target precoding matrix according to the calibration coefficient error statistical characteristic parameters and the uplink channel after correction and compensation, and in combination with the setting of the precoding algorithm. The antenna system precoding method disclosed in the present invention eliminates the uncertainty influence of the calibration coefficient error by introducing the calibration coefficient error statistical characteristic parameters, so that even in the case of a large calibration delay, the precoding method will not have obvious performance degradation.

[0146] Embodiment 2

[0147] Figure 3 A schematic diagram of the structure of an antenna system precoding device provided in Embodiment 2 of the present invention is shown in FIG. Figure 3 As shown, the device includes: a module 310 for determining an uplink channel after correction and compensation and a module 320 for determining a target precoding matrix.

[0148] The corrected uplink channel determination module 310 is used to obtain the initial uplink channel matrix, the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix, and determine the corrected uplink channel according to the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix.

[0149] The target precoding matrix determination module 320 is used to determine the calibration coefficient error statistical characteristic parameter, and obtain the target precoding matrix according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with the set precoding algorithm.

[0150] Optionally, the precoding algorithm is set to include a zero-forcing precoding algorithm, and the target precoding matrix determination module 320 is further used to:

[0151] The norm of the difference between the product of the precoding matrix and the downlink channel matrix and the unit matrix is ​​taken as the first target norm; wherein the downlink channel matrix is ​​related to the uplink channel after correction and compensation; according to the zero-forcing precoding algorithm, the expectation of the first target norm with respect to the statistical characteristic parameter of the calibration coefficient error is taken as the first target expectation function; and the precoding matrix that makes the first target expectation function take the minimum value is determined as the target precoding matrix.

[0152] Optionally, the device further includes an actual precoding matrix determining module 330, which is used to determine a power constraint factor, and determine the product of the power constraint factor and the target precoding matrix as the actual precoding matrix.

[0153] Optionally, the power constraint factor is determined according to a maximum transmit signal power of the signal transmitting end and an initial transmit signal power of the signal transmitting end without precoding.

[0154] Optionally, the precoding algorithm is set to include a Wiener precoding algorithm, and the target precoding matrix determination module 320 is further used to:

[0155] The product of the received signal and the gain factor is taken as the first product, and the norm of the difference between the transmitted signal and the first product is taken as the second target norm; wherein the received signal is related to the uplink channel after correction and compensation; according to the Wiener precoding algorithm, the expectation of the second target norm with respect to the statistical characteristic parameter of the calibration coefficient error, the transmitted signal and the receiving end noise is taken as the second target expectation function; and the precoding matrix that makes the second target expectation function take the minimum value and satisfies the power constraint condition is determined as the target precoding matrix.

[0156] Optionally, the precoding algorithm is set to include a minimum mean square error precoding algorithm, and the target precoding matrix determination module 320 is further used to:

[0157] The norm of the difference between the transmitted signal and the received signal is used as the third target norm; wherein the received signal is related to the uplink channel after correction and compensation; according to the minimum mean square error precoding algorithm, the expectation of the third target norm with respect to the statistical characteristic parameter of the calibration coefficient error, the transmitted signal and the receiving end noise is used as the third target expectation function; and the precoding matrix that makes the third target expectation function take the minimum value and satisfies the power constraint condition is determined as the target precoding matrix.

[0158] The antenna system precoding device provided in the embodiment of the present invention can execute the antenna system precoding method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0159] Embodiment 3

[0160] Figure 4 A schematic diagram of the structure of an electronic device 10 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0161] like Figure 4As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0162] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0163] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as an antenna system precoding method.

[0164] In some embodiments, the antenna system precoding method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the antenna system precoding described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to perform the antenna system precoding method in any other appropriate manner (e.g., by means of firmware).

[0165] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0166] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0167] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0168] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0169] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0170] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0171] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0172] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An antenna system precoding method, characterized in that: include: Acquire an initial uplink channel matrix, an access point side calibration coefficient matrix, and a user equipment side calibration coefficient matrix, and determine a corrected and compensated uplink channel according to the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix; A calibration coefficient error statistical characteristic parameter is determined, and a target precoding matrix is ​​obtained according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with a set precoding algorithm.

2. The method according to claim 1, characterized in that The setting precoding algorithm includes a zero-forcing precoding algorithm, and obtaining a target precoding matrix according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with the setting precoding algorithm, including: The norm of the difference between the product of the precoding matrix and the downlink channel matrix and the unit matrix is ​​used as the first target norm; wherein the downlink channel matrix is ​​related to the corrected and compensated uplink channel; According to the zero-forcing precoding algorithm, taking the expectation of the first target norm with respect to the calibration coefficient error statistical characteristic parameter as a first target expectation function; A precoding matrix that minimizes the first objective expectation function is determined as the target precoding matrix.

3. The method according to claim 2, characterized in that After obtaining the target precoding matrix, it also includes: A power constraint factor is determined, and a product of the power constraint factor and the target precoding matrix is ​​determined as an actual precoding matrix.

4. The method according to claim 3, characterized in that The power constraint factor is determined according to the maximum signal transmission power of the signal transmitting end and the initial signal transmission power of the signal transmitting end without precoding.

5. The method according to claim 1, characterized in that The setting precoding algorithm includes a Wiener precoding algorithm, and obtaining a target precoding matrix according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with the setting precoding algorithm, including: The product of the received signal and the gain factor is used as a first product, and the norm of the difference between the transmitted signal and the first product is used as a second target norm; wherein the received signal is related to the corrected and compensated uplink channel; According to the Wiener precoding algorithm, taking the expectation of the second target norm with respect to the calibration coefficient error statistical characteristic parameter, the transmission signal and the receiving end noise as a second target expectation function; A precoding matrix that minimizes the second objective expectation function and satisfies a power constraint condition is determined as the target precoding matrix.

6. The method according to claim 1, characterized in that The setting precoding algorithm includes a minimum mean square error precoding algorithm, and obtaining a target precoding matrix according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with the setting precoding algorithm, including: Taking the norm of the difference between the transmitted signal and the received signal as the third target norm; wherein the received signal is related to the corrected and compensated uplink channel; According to the minimum mean square error precoding algorithm, taking the expectation of the third target norm with respect to the calibration coefficient error statistical characteristic parameter, the transmission signal and the receiving end noise as a third target expectation function; A precoding matrix that minimizes the third objective expectation function and satisfies a power constraint condition is determined as the target precoding matrix.

7. An antenna system precoding device, characterized in that: include: A module for determining a corrected uplink channel, configured to obtain an initial uplink channel matrix, an access point side calibration coefficient matrix, and a user equipment side calibration coefficient matrix, and determine a corrected uplink channel according to the access point side calibration coefficient matrix and the user equipment side calibration coefficient matrix; The target precoding matrix determination module is used to determine the calibration coefficient error statistical characteristic parameter, and obtain the target precoding matrix according to the calibration coefficient error statistical characteristic parameter and the corrected and compensated uplink channel in combination with the set precoding algorithm.

8. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the antenna system precoding method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the antenna system precoding method according to any one of claims 1 to 6 when executed.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the antenna system precoding method according to any one of claims 1 to 6 are implemented.

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