High spectral efficiency transmission method and system of cellular D2D wireless communication system

Abstract

The invention relates to the technical field of wireless communication, and provides a high spectral efficiency transmission method and system for a cellular D2D wireless communication system, and the method comprises the steps: building a D2D communication system, and obtaining an energy charging phase shift angle, a communication phase shift angle and energy charging time; constructing a system throughput function, and updating the energy charging time through the system throughput and an SQP algorithm; performing Lagrange dual transformation on the system throughput function to obtain a target Lagrange transformation auxiliary variable and a first intermediate function; performing multi-dimensional complex quadratic transformation on the first intermediate function to obtain a second intermediate function, and performing alternate optimization to obtain a target transformation intermediate variable and a third intermediate function; obtaining a target trace function through semi-definite relaxation, and finally obtaining a target complex semi-definite matrix, thereby obtaining a target charging phase shift angle; and resolving a target communication phase shift angle to complete optimization of the D2D communication system. The throughput of the communication system can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a high spectrum efficiency transmission method and system for a cellular D2D wireless communication system. Background Art

[0002] The existing IRS (Intelligent Reflecting Surface) assisted D2D (Device-to-Device) communication devices and combined with WPCN (Wireless Powered Communication Network) for communication, although trying to combine these three technologies, most of them use TDMA (Time Division Multiple Access) and FDM (Frequency Division Multiplexing) to manage D2D communication. Although TDMA can reduce co-channel interference by dividing time into multiple time slots, its spectrum utilization efficiency is low and it fails to fully realize the potential of the combination of IRS, D2D and WPCN. In addition, TDMA's fixed time slot allocation lacks flexibility in the face of dynamically changing network environments, especially when dealing with high-density user access. Specifically, it is easy to cause unbalanced allocation of system resources, resulting in performance bottlenecks in large-scale network applications. On the other hand, although FDM reduces interference by dividing the spectrum into multiple sub-bands, it also has significant disadvantages. FDM requires the allocation of independent frequency band resources for each user, which leads to the dispersion and waste of spectrum resources, especially when spectrum resources are already limited, which further exacerbates the low spectrum utilization. In addition, when facing frequency selective fading, frequency band division may lead to unstable signal quality and affect the reliability of communication. More importantly, in the scenario of multi-user sharing, the complexity and management cost of frequency band allocation increase significantly with the increase of the number of users, further limiting the scalability of the system. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the present invention provides a high spectrum efficiency transmission method and system for a cellular D2D wireless communication system, so as to improve the throughput of the D2D communication system.

[0004] The present invention provides a high spectrum efficiency transmission method for a cellular D2D wireless communication system, comprising: S1: Acquire an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and acquire a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; S2: constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; S3: performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; S4: performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; S5: obtaining a target trace function by performing semidefinite relaxation on the third intermediate function, solving the target trace function to obtain a target complex semidefinite matrix, performing Gaussian randomization on the target complex semidefinite matrix to obtain a target charging phase shift angle; S6: Calculate the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

[0005] According to the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention, the AP module is connected to the D2D device, and the AP module charges the D2D device during operation.

[0006] According to the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention, step S3 further includes: S31: performing Lagrange dual transformation on the system throughput function to obtain a Laplace transform intermediate function and a Laplace transform auxiliary variable, and alternately optimizing the Laplace transform auxiliary variable to obtain the target Laplace transform auxiliary variable; S32: Substitute the target Laplace transform auxiliary variable into the Laplace transform intermediate function to obtain the first intermediate function.

[0007] According to the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention, step S4 further includes: S41: performing a multi-dimensional complex quadratic transformation on the first intermediate function to obtain a transformed intermediate variable and the second intermediate function, and alternately optimizing the transformed intermediate variable to obtain the target transformed intermediate variable; S42: Substitute the target transformation intermediate variable into the second intermediate function to obtain the third intermediate function.

[0008] According to the high spectral efficiency transmission method of the cellular D2D wireless communication system provided by the present invention, in step S5, the semidefinite relaxation specifically includes: constructing a semidefinite relaxation intermediate variable through the third intermediate function, removing the non-convex constraints in the semidefinite relaxation intermediate variable and changing them to convex constraints to obtain the target semidefinite relaxation intermediate variable, and constructing the target trace function through the target semidefinite relaxation intermediate variable and the third intermediate function.

[0009] According to the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention, the system throughput function is: Where R is the system throughput function, t is the charging time, N is the total number of D2D device pairs, For the The signal-to-interference-plus-noise ratio (SINR) of a signal receiving device is determined based on the signal-to-interference-plus-noise ratio (SINR). The SINR includes the charging phase shift angle and the communication phase shift angle.

[0010] The present invention also provides a high spectrum efficiency transmission system for a cellular D2D wireless communication system, comprising: D2D communication system construction module: used to obtain an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and obtain a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; Charging time updating module: used for constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; A first intermediate function module: used for performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; A third intermediate function module: used for performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; Target charging phase shift angle module: used to obtain a target trace function by performing semidefinite relaxation on the third intermediate function, solve the target trace function to obtain a target complex semidefinite matrix, perform Gaussian randomization on the target complex semidefinite matrix, and obtain a target charging phase shift angle; Communication system optimization module: used to solve the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

[0011] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the high spectrum efficiency transmission method of the cellular D2D wireless communication system as described above are implemented.

[0012] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the above-mentioned high spectral efficiency transmission methods for a cellular D2D wireless communication system.

[0013] The present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the steps of the high spectral efficiency transmission method for a cellular D2D wireless communication system as described in any one of the above-mentioned methods.

[0014] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: The high spectrum efficiency transmission method and system of the cellular D2D wireless communication system provided by the present invention realizes the maximization of system throughput by comprehensively using D2D communication, IRS and WPCN technologies, and by jointly optimizing the energy collection time and the phase adjustment of IRS in two stages. In addition, the present invention also effectively reduces the co-channel interference caused by multiple users multiplexing the same spectrum resources by adjusting the phase and communication time, ensuring that more D2D users can be connected under the premise of meeting the basic service quality. Thereby improving the system throughput, achieving the improvement of communication efficiency, and also improving the spectrum utilization, enhancing the robustness and efficiency of the system in complex environments.

[0015] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a flow chart of the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention.

[0018] Figure 2It is a schematic diagram of system throughput under different numbers of passive reflective devices of the high spectral efficiency transmission method of the cellular D2D wireless communication system provided by the present invention.

[0019] Figure 3 It is a schematic diagram of system throughput under different AP module transmission powers of the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention.

[0020] Figure 4 It is a schematic diagram of system throughput under different numbers of D2D device pairs of the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention.

[0021] Figure 5 It is a schematic diagram of system throughput at different distances between the IRS module and the AP module of the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention.

[0022] Figure 6 It is a structural schematic diagram of the high spectrum efficiency transmission system of the cellular D2D wireless communication system provided by the present invention.

[0023] Figure 7 It is a structural schematic diagram of a high spectrum efficiency transmission device of a cellular D2D wireless communication system provided by the present invention.

[0024] Reference numerals: 100, D2D communication system building module; 200, charging time update module; 300, first intermediate function module; 400, third intermediate function module; 500, target charging phase shift angle module; 600, communication system optimization module; 810, processor; 820, communication interface; 830, memory; 840, communication bus. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0026] In the description of the embodiments of the present invention, it should be noted that the terms “first”, “second” and “third” are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0027] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0028] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0029] Combine the following Figures 1 to 7 Describing embodiments of the present invention: Figure 1 A flow chart of a high spectral efficiency transmission method for a cellular D2D wireless communication system provided by the present invention, wherein S1 is to build a D2D communication system and obtain a charging phase shift angle, a communication phase shift angle and a charging time; S2 is to construct a system throughput function to update the charging time; S3 is to perform a Lagrange dual transformation to obtain a first intermediate function; S4 is to perform a multi-dimensional complex quadratic transformation to obtain a third intermediate function; S5 is to perform semidefinite relaxation and Gaussian randomization to obtain a target charging phase shift angle; S6 is to solve a target communication phase shift angle, and finally complete the optimization of the D2D communication system.

[0030] The high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the present invention includes: S1: Acquire an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and acquire a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; Furthermore, the purpose of this stage is to build a D2D communication system and obtain the charging phase shift angle, communication phase shift angle and charging time of the D2D communication system, so as to obtain the updated charging time, target charging phase shift angle and target communication phase shift angle based on the obtained charging phase shift angle, communication phase shift angle and charging time. The specific implementation method is to first obtain an AP (Access Point) device and a D2D device. Here, the AP device is a single-antenna device for implementing WPCN and uses it as an AP module, and is wirelessly connected to each D2D device to charge each D2D device wirelessly. Each D2D device communicates with each other through a communication channel connection, and the D2D device obtains energy sent from the AP module during the charging time. After charging is completed, the energy obtained from the AP module is used for communication, which effectively improves its own transmission power.

[0031] In addition, the AP module and each D2D device are also connected to the IRS module respectively. The IRS module is composed of multiple passive reflective devices. The signals sent by the AP module and each D2D device are first transmitted to the IRS module and then reflected to the receiving object of the signal by the ISR module. It can phase shift the signals sent by the AP module and the D2D device and then reflect them to the receiving object of the signal, thereby increasing the coverage, reducing interference, and improving the performance of the communication system. In the charging stage, the IRS module phase shifts the energy signal sent by the AP module. The phase shift angle at this time is the charging phase shift angle, and the time spent on charging is the charging time. In the communication stage, the IRS module phase shifts the communication signal sent by the D2D device. The phase shift angle at this time is the communication phase shift angle.

[0032] S2: constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; Furthermore, the purpose of this stage is to construct a system throughput function, thereby optimizing the charging phase shift angle, communication phase shift angle and charging time, so that the system throughput is maximized, and the charging time can be directly updated to determine the most appropriate charging time. Optimizing the charging phase shift angle and communication phase shift angle can effectively avoid co-channel interference caused by multiple users multiplexing the same spectrum resources. The specific implementation method is to first define the beamforming matrix of the IRS module as , and τ is 0 in the charging phase and 1 in the communication phase, , where diag() constructs a diagonal matrix using the elements in brackets, τ is the phase characterization parameter, In the process, when τ is 0, it is in the charging stage. is the charging phase shift angle. When τ is 1, it is in the communication stage. is the communication phase shift angle, and , where T represents the transpose, j represents the imaginary unit, and M represents the number of passive reflectors in the IRS module. Here, the real part of the angle represented by the complex number is 1. represents the phase shift angle provided by the 1st to Mth passive reflectors in the IRS module, and when τ is 0 and 1 All have a given initial value, and the value of τ is 0 or 1.

[0033] Next, define the nth signal sending device in the D2D device as , the nth signal receiving device is , and these two devices form a D2D device pair. It should be noted here that as long as a channel is established between two D2D devices, a communication relationship of sending and receiving is formed to form a D2D device pair. Therefore, a D2D device can exist in multiple D2D device pairs, and in each D2D device pair it is regarded as a signal sending device or a signal receiving device. The number of D2D device pairs is equal to the number of signal sending devices or the number of signal receiving devices; each D2D device pair includes a communication channel, and each communication channel has its own channel vector. Within the preset charging time t, the AP module is Sending energy signals ,at this time Received signal It can be expressed as: in, Indicates the channel vector from the AP module to the nth signal-emitting device. Represents the channel vector from the IRS module to the nth signal emitting device, Represents the channel vector from the AP module to the IRS module, is the transmit power of the AP module, The receiving noise of the nth signal emitting device, is the beamforming matrix in the charging phase, where the channel vector is a vector used to represent channel information. Then, the total energy received by the nth signal-emitting device in the charging phase can be obtained as for: in, Indicates the energy conversion efficiency of the known n-th signal emitting device. Since the signal emitting device will use all the received energy for communication during the communication phase, in this embodiment, the sum of the time of the charging phase and the communication phase is set to 1, then the time of the communication phase can be expressed as (1-t), at which time the transmission power of the n-th signal emitting device is for: The data signal it sends is , then the signal received by the nth signal receiving device is for: in, is the beamforming matrix in the communication phase, is the channel vector from the nth signal sending device to the nth signal receiving device, represents the channel vector from the IRS module to the nth signal receiving device, Express Perform complex conjugate transpose, where N is the total number of D2D device pairs. The data signal sent by the nth signal sending device, For the a channel vector from a signal sending device outside the D2D device pair to the nth signal receiving device; Indicates the IRS module to The channel vector of the signal transmitting device other than the D2D device is complex conjugate transposed. For the The transmission power of the signal transmitting device outside the D2D device pair, For the A data signal sent by a signal sending device outside the D2D device pair, The crosstalk of the signal-emitting devices outside the D2D device pair will interfere with the communication process. is the receiving noise of the nth signal receiving device. These parameters can be obtained based on the channel vector and device parameters as well as the monitoring of the signals and data sent and received by the device. It is particularly important to note that The calculation method of Same, except that the corner marks becomes n.

[0034] In this way, the signal-to-interference-to-noise ratio of the nth signal receiving device communication can be obtained : in, is the variance of the received noise.

[0035] Thus, the system throughput function R can be constructed: Since the system throughput function includes t, and , so the three parameters can be optimized separately. First, t is optimized, so we have: in, represents the value of t when R takes the maximum value. At this time, since the original expression is more complicated, the first auxiliary variable is introduced and the second auxiliary variable : in, For the The energy conversion efficiency of the signaling device outside the D2D device pair, For AP module to The channel vector of the signaling device outside the D2D device pair, For IRS module to The channel vector of the signal sending device outside the D2D device pair can be obtained: The equation is then solved using the SQP (Sequential Quadratic Programming) algorithm to update the charging time, that is, to replace the previously given charging time with the charging time that maximizes the system throughput.

[0036] S3: performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; Furthermore, the purpose of this stage is to obtain a first intermediate function to prepare for subsequent transformation and calculation. Specifically, step S3 further includes: S31: performing Lagrange dual transformation on the system throughput function to obtain a Laplace transform intermediate function and a Laplace transform auxiliary variable, and alternately optimizing the Laplace transform auxiliary variable to obtain the target Laplace transform auxiliary variable; S32: Substitute the target Laplace transform auxiliary variable into the Laplace transform intermediate function to obtain the first intermediate function.

[0037] With respect to the above steps, the specific implementation of this embodiment is as follows: Since the target charging phase shift angle needs to be calculated next, the target of function optimization is the charging phase shift angle. At this time, we can get: in, It means that when R reaches the maximum value The value of For the updated charging time, Indicates that the following is a constraint condition, express The modulus of the element in the mth row and mth column in , where M is the number of passive reflectors in the IRS module. In order to simplify the expression, the third auxiliary variable is introduced and the fourth auxiliary variable ,at this time Can be rewritten as: Then, including the rewritten The Lagrange dual transformation of the system throughput function can be used to obtain the Laplace transform auxiliary variable including the nth signal receiving device. The Laplace transform intermediate function : At this time, the Laplace transform auxiliary variables are optimized alternately, that is, for the two variables of the Laplace transform intermediate function, first fix ,Change So that the Laplace transform intermediate function takes the maximum value, in the Laplace transform intermediate function, when = When the Laplace transform intermediate function takes the maximum value, the target Laplace transform auxiliary variable of the nth signal receiving device is obtained. : Finally, substitute the target Laplace transform auxiliary variable into the Laplace transform intermediate function to obtain the first intermediate function : in, When the function reaches its maximum value Here we introduce the fifth auxiliary variable , the sixth auxiliary variable , the seventh auxiliary variable , the eighth auxiliary variable and the ninth auxiliary variable , the first intermediate function can be rewritten through matrix operations as: in, To perform complex conjugate transposition on the charging phase shift angle.

[0038] S4: performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; Furthermore, the purpose of this stage is to obtain a third intermediate function, and then obtain a target trace function. Specifically, step S4 further includes: S41: performing a multi-dimensional complex quadratic transformation on the first intermediate function to obtain a transformed intermediate variable and the second intermediate function, and alternately optimizing the transformed intermediate variable to obtain the target transformed intermediate variable; S42: Substitute the target transformation intermediate variable into the second intermediate function to obtain the third intermediate function.

[0039] With respect to the above steps, the specific implementation of this embodiment is as follows: Performing a multidimensional complex quadratic transformation on the first intermediate function can obtain a second intermediate function including the transformed intermediate variable. : in, is the transformed intermediate variable of the nth signal receiving device, Re{} represents taking the conjugate of the transformation intermediate variable of the nth signal receiving device, and Re{} represents taking the real part of the number in the brackets. Then, the transformation intermediate variable and the charging phase shift angle are alternately optimized, that is, the value of the charging phase shift angle is fixed first, and the value of the intermediate variable is changed so that the second intermediate function takes the maximum value. The target transformation intermediate variable of the nth signal receiving device is for: In addition, the second intermediate function Rewritten as: in, To perform the complex conjugate transpose of the sixth auxiliary variable, To conjugate the eighth auxiliary variable. Substitute the target transformation intermediate variable and the elements of the rewritten second intermediate function into the second intermediate function to obtain the third intermediate function : in: here, When the function reaches its maximum value The value of , W is the correction constant determined based on experience, U is the first auxiliary function, is the second auxiliary function. Since the fifth auxiliary variable is a positive definite matrix, the first auxiliary function is also a positive definite matrix and the third intermediate function is a quadratic concave function.

[0040] S5: obtaining a target trace function by performing semidefinite relaxation on the third intermediate function, solving the target trace function to obtain a target complex semidefinite matrix, performing Gaussian randomization on the target complex semidefinite matrix to obtain a target charging phase shift angle; Furthermore, the purpose of this stage is to obtain the target charging phase shift angle through semidefinite relaxation and Gaussian randomization of the third intermediate function. In step S5, the semidefinite relaxation specifically includes: constructing a semidefinite relaxation intermediate variable through the third intermediate function, removing the non-convex constraints in the semidefinite relaxation intermediate variable and changing them to convex constraints, obtaining the target semidefinite relaxation intermediate variable, and constructing the target trace function through the target semidefinite relaxation intermediate variable and the third intermediate function. The specific implementation method is: Since the third intermediate function is still non-convex, it is a QCQP (quadratic constrainedquadratic programming) problem, so semidefinite relaxation can be used. The specific steps of semidefinite relaxation include: first, and To expand the dimension, and Add an element 1 to each of them, so that the first semidefinite relaxation intermediate parameter can be obtained ,in , and the second semidefinite relaxation intermediate parameter ,in , and then construct the semidefinite relaxation intermediate variable through the first semidefinite relaxation intermediate parameter and the second semidefinite relaxation intermediate parameter ,in , remove the non-convex constraints in the semidefinite relaxed intermediate variables and change them to convex constraints, and get the target semidefinite relaxed intermediate variables , the target trace function can be constructed through the target semidefinite relaxation intermediate variable and the third intermediate function : in, Indicates when the function reaches its maximum value The value of express The modulus of the element in the mth row and mth column, is the target auxiliary function, To perform the complex conjugate transpose of the second auxiliary function, Tr() represents the trace function for calculating the value in the brackets.

[0041] At this time, since the target trace function is already a convex optimization problem, the problem can be solved by importing the target trace function into the CVX (Convex Optimization) tool in MATLAB to obtain a target complex semi-definite matrix with a dimension of M+1. The target complex semi-definite matrix is ​​Gaussian randomized to obtain the target charging phase shift angle. After obtaining the target charging phase shift angle, when the charging time is determined, the above method is used and the optimization object is replaced with the communication phase shift angle for calculation to obtain the target communication phase shift angle. The updated charging time, target charging phase shift angle and target communication phase shift angle are substituted into the D2D communication system for communication, thereby completing the optimization of the D2D communication system. In addition, the optimized charging time, target charging phase shift angle and target communication phase shift angle can be re-optimized as given initial values, and the process is repeated several times to iterate the optimized charging time, target charging phase shift angle and target communication phase shift angle until the predetermined number of iterations is reached, thereby further improving the optimization level of the D2D communication system and maximizing the system throughput.

[0042] The present invention also verifies the effectiveness of the high spectrum efficiency transmission method of the cellular D2D wireless communication system. During the verification, the following schemes are selected for comparison: Scheme of the present invention: that is, a scheme using the method of the present invention.

[0043] No IRS solution (No IRS): In this solution, the IRS module is not used, that is, the system does not use the intelligent reflective surface for signal reflection and optimization.

[0044] Random Phase: In this scheme, the phase shift angle of the IRS module is randomly set without optimization.

[0045] 1st Stage Phase Opt.: This scheme optimizes the charging phase shift angle but not the communication phase shift angle.

[0046] Second Stage Phase Opt.: This solution only optimizes the communication phase shift angle but not the charging phase shift angle.

[0047] Fixed EH Time: In this solution, the charging time is not optimized.

[0048] Traditional solution: This solution adopts the solution of the traditional D2D communication system for comparison. The traditional solution in this embodiment can be found in "Reconfigurable intelligent surfaces for energy efficiency in d2dcommunication network", S. Jia, X. Yuan, and Y.-C. Liang, "IEEE Wireless Communications Letters", Vol. 10, No. 3.

[0049] Figure 2 Schematic diagram of system throughput under different numbers of passive reflective devices. The D2D device is a mobile phone or a wearable smart device. It can be observed that as the number of passive reflective devices increases, the total system throughput also increases. This is because the increase in passive reflective devices provides more reflection paths for wireless charging and D2D communication. It can be seen that the method provided by the present invention performs best, highlighting the importance of optimizing phase shift in two stages. Compared with other schemes, the slope of the method used in the present invention and the fixed charging time scheme is steeper, because the optimization of the communication phase shift angle and the charging phase shift angle significantly enhances the effect of the IRS module. This shows that the method of the present invention has significant advantages in improving system throughput. The unit of system throughput here is bits per second / Hertz (ie, bps / Hz).

[0050] Figure 3 Schematic diagram of system throughput under different AP module transmission powers. The system throughput increases with the increase of AP module transmission power. This is because, with the increase of transmission power, the energy obtained by the D2D device in the wireless charging stage also increases, so that the D2D device can send data signals at a higher power in the communication stage, thereby improving the data transmission rate. The method of the present invention has the best system throughput under different AP module transmission powers, which proves its adaptability and superiority under different power conditions. The AP module transmission power is decibel milliwatt, i.e. dBm.

[0051] Figure 4 Schematic diagram of system throughput under different numbers of D2D device pairs. As the number of D2D device pairs increases, the system throughput also increases. This trend can be attributed to the increase in channels between devices. As more D2D device pairs share the same spectrum resources, spectrum utilization becomes more efficient, thereby improving resource utilization and ultimately leading to higher system throughput. In addition, the deployment and optimization strategy of the IRS module significantly improves the interference management between D2D device pairs, further promoting the increase in system throughput. It can be seen that the solution proposed in the present invention can effectively improve system performance when dealing with multi-user scenarios, and has obvious advantages.

[0052] Figure 5 Schematic diagram of system throughput at different distances between the IRS module and the AP module. When the IRS module is deployed at the edge center of the rectangular area and close to the AP module, the system throughput is optimal. This is because the D2D devices are randomly distributed in the rectangular area, and the IRS module deployed in the center can better serve the D2D devices distributed in various areas, and shorten the reflection path of the D2D device as much as possible to reduce the path loss, thereby improving the channel gain. It is more effective to deploy the IRS module close to the AP module than far away from the AP module, because the distance between the AP module and the IRS module is closer, which provides lower path loss and higher channel gain during the charging stage. The above results prove that the method of the present invention has the maximum system throughput at different distances between the IRS module and the AP module, and can better adapt to different scenario requirements in actual applications. The unit of the distance between the IRS module and the AP module is meter.

[0053] The high spectral efficiency transmission system of the cellular D2D wireless communication system provided by the present invention is described below. The high spectral efficiency transmission system of the cellular D2D wireless communication system described below and the high spectral efficiency transmission method of the cellular D2D wireless communication system described above can be referenced to each other.

[0054] Figure 6 Schematic diagram of the structure of a high spectrum efficiency transmission system for a cellular D2D wireless communication system. Figure 6 As shown, the high spectrum efficiency transmission method for executing the cellular D2D wireless communication system as described above includes: D2D communication system construction module 100: used to obtain an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and obtain a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; Charging time updating module 200: used to construct a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and update the charging time through the system throughput function and the SQP algorithm; The first intermediate function module 300 is used to perform Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtain a first intermediate function through the target Laplace transform auxiliary variable; The third intermediate function module 400 is used to perform multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtain a third intermediate function through the target transformation intermediate variable and the second intermediate function; The target charging phase shift angle module 500 is used to obtain a target trace function by performing semidefinite relaxation on the third intermediate function, solve the target trace function to obtain a target complex semidefinite matrix, perform Gaussian randomization on the target complex semidefinite matrix, and obtain a target charging phase shift angle; The communication system optimization module 600 is used to calculate the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

[0055] on the other hand, Figure 7 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 7 As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830 and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 may call the logic instructions in the memory 830 to execute the high spectrum efficiency transmission method of the cellular D2D wireless communication system, and the method includes: S1: Acquire an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and acquire a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; S2: constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; S3: performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; S4: performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; S5: obtaining a target trace function by performing semidefinite relaxation on the third intermediate function, solving the target trace function to obtain a target complex semidefinite matrix, performing Gaussian randomization on the target complex semidefinite matrix to obtain a target charging phase shift angle; S6: Calculate the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

[0056] In addition, the logic instructions in the above-mentioned memory 830 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0057] On the other hand, the present invention further provides a computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, when the program instructions are executed by a computer, the computer can execute the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the above methods, the method comprising: S1: Acquire an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and acquire a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; S2: constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; S3: performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; S4: performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; S5: obtaining a target trace function by performing semidefinite relaxation on the third intermediate function, solving the target trace function to obtain a target complex semidefinite matrix, performing Gaussian randomization on the target complex semidefinite matrix to obtain a target charging phase shift angle; S6: Calculate the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

[0058] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the high spectrum efficiency transmission method of the cellular D2D wireless communication system provided by the above methods is implemented, and the method includes: S1: Acquire an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and acquire a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; S2: constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; S3: performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; S4: performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; S5: obtaining a target trace function by performing semidefinite relaxation on the third intermediate function, solving the target trace function to obtain a target complex semidefinite matrix, performing Gaussian randomization on the target complex semidefinite matrix to obtain a target charging phase shift angle; S6: Calculate the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

[0059] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0060] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high spectrum efficiency transmission method for a cellular D2D wireless communication system, characterized in that: include: S1: Acquire an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and acquire a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; S2: constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; S3: performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; S4: performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; S5: obtaining a target trace function by performing semidefinite relaxation on the third intermediate function, solving the target trace function to obtain a target complex semidefinite matrix, performing Gaussian randomization on the target complex semidefinite matrix to obtain a target charging phase shift angle; S6: Calculate the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

2. The high spectrum efficiency transmission method of a cellular D2D wireless communication system according to claim 1, characterized in that: The AP module is connected to the D2D device, and the AP module charges the D2D device during operation.

3. The high spectrum efficiency transmission method of a cellular D2D wireless communication system according to claim 1, characterized in that: Step S3 further comprises: S31: performing Lagrange dual transformation on the system throughput function to obtain a Laplace transform intermediate function and a Laplace transform auxiliary variable, and alternately optimizing the Laplace transform auxiliary variable to obtain the target Laplace transform auxiliary variable; S32: Substitute the target Laplace transform auxiliary variable into the Laplace transform intermediate function to obtain the first intermediate function.

4. The high spectrum efficiency transmission method of a cellular D2D wireless communication system according to claim 1, characterized in that: Step S4 further comprises: S41: performing a multi-dimensional complex quadratic transformation on the first intermediate function to obtain a transformed intermediate variable and the second intermediate function, and alternately optimizing the transformed intermediate variable to obtain the target transformed intermediate variable; S42: Substitute the target transformation intermediate variable into the second intermediate function to obtain the third intermediate function.

5. The high spectrum efficiency transmission method of a cellular D2D wireless communication system according to claim 1, characterized in that: In step S5, the semidefinite relaxation specifically includes: constructing a semidefinite relaxation intermediate variable through the third intermediate function, removing the non-convex constraints in the semidefinite relaxation intermediate variable and changing them to convex constraints, obtaining the target semidefinite relaxation intermediate variable, and constructing the target trace function through the target semidefinite relaxation intermediate variable and the third intermediate function.

6. The high spectrum efficiency transmission method of a cellular D2D wireless communication system according to claim 1, characterized in that: The system throughput function is: Where R is the system throughput function, t is the charging time, N is the total number of D2D device pairs, For the The signal-to-interference-plus-noise ratio (SINR) of a signal receiving device is determined based on the signal-to-interference-plus-noise ratio (SINR). The SINR includes the charging phase shift angle and the communication phase shift angle.

7. A high spectrum efficiency transmission system of a cellular D2D wireless communication system, used to execute the high spectrum efficiency transmission method of a cellular D2D wireless communication system according to any one of claims 1 to 6, characterized in that: include: D2D communication system construction module: used to obtain an AP module, an IRS module and a D2D device, build a D2D communication system through the AP module, the IRS module and the D2D device, and obtain a charging phase shift angle, a communication phase shift angle and a charging time of the D2D communication system; Charging time updating module: used for constructing a system throughput function through the charging phase shift angle, the communication phase shift angle and the charging time, and updating the charging time through the system throughput function and the SQP algorithm; A first intermediate function module: used for performing Lagrange dual transformation and alternating optimization on the system throughput function to obtain a target Laplace transform auxiliary variable, and obtaining a first intermediate function through the target Laplace transform auxiliary variable; A third intermediate function module: used for performing multi-dimensional complex quadratic transformation and alternating optimization on the first intermediate function to obtain a second intermediate function and a target transformation intermediate variable, and obtaining a third intermediate function through the target transformation intermediate variable and the second intermediate function; Target charging phase shift angle module: used to obtain a target trace function by performing semidefinite relaxation on the third intermediate function, solve the target trace function to obtain a target complex semidefinite matrix, perform Gaussian randomization on the target complex semidefinite matrix, and obtain a target charging phase shift angle; Communication system optimization module: used to solve the target communication phase shift angle, substitute the updated charging time, the target charging phase shift angle and the target communication phase shift angle into the D2D communication system, and complete the optimization of the D2D communication system.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the high spectrum efficiency transmission method for a cellular D2D wireless communication system as described in any one of claims 1 to 6 are implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the high spectrum efficiency transmission method for a cellular D2D wireless communication system as claimed in any one of claims 1 to 6 are implemented.

10. A computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, characterized in that: When the program instructions are executed by a computer, the computer can execute the steps of the high spectrum efficiency transmission method for a cellular D2D wireless communication system as claimed in any one of claims 1 to 6.

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