Robust Transmission Scheme for Physical Layer Security of IRS-Assisted Wireless Energy Harvesting Communication Systems

Abstract

The present invention relates to a physical layer security robust transmission scheme for an IRS-assisted wireless power supply communication system, belonging to the field of wireless communication technologies. It includes the following steps: Step 1: Establishment of a robust optimization system architecture for IRS-assisted WPCN secure communication; Step 2: Optimization of the energy and information transmission between the HAP and the user, including the following steps: Energy and information transmission between the HAP and the user; Optimization method. The WPCN secure communication system provided by the present invention utilizes an IRS-assisted communication system and conducts robust design, thereby improving the secrecy rate of the system; in the information transmission mode of the present invention, the beamforming technology in physical layer security is utilized to increase the information transmission rate gap between legitimate users and eavesdropping users, further ensuring the security of the information transmitted by users.

Description

Technical Field

[0001] The present invention relates to a secure transmission method for an IRS-assisted wireless power supply communication system, belonging to the field of wireless communication technology. Background Art

[0002] In recent years, the rapid development of information technology has pushed the Internet of Things (IoT) to the forefront of global technological innovation and industrial transformation. Its application scope widely covers various fields such as smart cities, smart homes, industrial Internet, healthcare, intelligent transportation systems, and intelligent management of the agricultural Internet of Things. According to the latest data authoritatively released by the Ministry of Industry and Information Technology, the connection scale of IoT terminals has historically exceeded approximately 10 billion, accounting for more than one-third of the total global IoT connections. At the same time, the number of mobile user groups has reached millions and is continuously increasing at an annual growth rate of approximately 25%. It is expected that by 2030, the number of IoT terminal connections will grow to 80 billion. The patent with publication number CN113794493A, titled "A Beamforming Method, Device, Computer Equipment, and Storage Medium", discloses a performance optimization solution in the technical background of a cognitive radio (CR) system in its technical solution, which solves the problem of user service quality in the case of conflicts between primary and secondary users. Its robustness optimization is reflected in considering that the channel conditions are imperfect and adopting a channel model with CSI estimation error.

[0003] Maintaining the normal operation of a large number of energy-constrained devices and ensuring the security of the information transmission phase are key challenges in IoT (Internet of Things) design. In the face of the problem of energy constraint, traditional wireless networks often charge the device batteries to meet their continuous energy requirements; or replace the batteries of these devices regularly. However, such operations will consume a large amount of manpower and material resources, and there may be a phenomenon of communication interruption. For the information transmission security problem, it mainly focuses on application layer encryption technology, using private keys to perform data encryption processing, and the receiving end decrypts the data according to the corresponding key. However, in the face of the large-scale connection requirements in the IoT scenario, distributing and managing keys will become extremely complex and time-consuming.

[0004] The existing methods for maintaining the normal operation of energy-constrained devices and ensuring secure information transmission in the IoT scenario mainly have the following defects:

[0005] 1) The existing solutions require frequent replacement of the batteries of wireless devices, which will cause waste of resources and occurrence of communication interruption;

[0006] 2) Most of the existing methods for ensuring secure information transmission use encryption technology, but the process of managing and distributing it in a large-scale connection scenario will be very complex.

[0007] Therefore, it is urgent to propose a physical layer security robust transmission scheme for IRS-assisted wireless power supply communication systems to solve the above technical problems. Summary of the Invention

[0008] To solve the above problems, a physical layer security robust transmission scheme for IRS-assisted wireless power supply communication systems is provided. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0009] Technical solution of the present invention:

[0010] A physical layer security robust transmission scheme for IRS-assisted wireless power supply communication systems includes the following steps:

[0011] Step 1: Establishment of an IRS-assisted WPCN secure communication robust optimization system architecture;

[0012] Step 2: Optimize the transmission of energy and information between the HAP and the user, including the following steps:

[0013] Step 2.1: Transmission of energy and information between the HAP and the user;

[0014] Step 2.2: Optimization method.

[0015] Preferably: In step 1, the IRS-assisted wireless power supply communication system includes a HAP, a wireless device, an eavesdropper, and an IRS;

[0016] HAP (Hybrid Access Point): Responsible for energy transmission and information transmission; Communicates with the wireless device through a wireless connection;

[0017] Wireless device (a legitimate single-antenna energy-constrained wireless device user): Communicates with the HAP through a wireless connection and receives energy from the HAP to maintain communication;

[0018] Eavesdropper (a single-antenna eavesdropper eve): A single-antenna device used to eavesdrop on the communication between the HAP and the wireless device;

[0019] IRS (Intelligent Reflecting Surface): The IRS is equipped with reflecting units for enhancing the signal transmission between the HAP and the wireless device;

[0020] During the energy transmission process, a channel is established between the HAP and the IRS, and then the energy is transmitted to the wireless device through the IRS reflecting unit. In the information transmission stage, the channel from the wireless device to the HAP is used for uplink information transmission, while the channel from the IRS to the HAP is used for downlink energy transmission.

[0021] Preferably, in step 1, the IRS-assisted wireless power transfer communication system consists of an HAP with N antennas, a wireless device, an eavesdropper, and an IRS equipped with M reflecting elements. In the uplink and downlink phases, the reflection factors of the IRS reflecting elements are different; N and M are natural numbers, and T represents transpose;

[0022] The reflection coefficients in the uplink and downlink phases can be respectively expressed as and The reflection matrices can be respectively expressed as During the energy transfer process, the channel between the HAP and the IRS is established as The channel between the HAP and the wireless device is established as The channel between the IRS and the wireless device is established as During the information transmission phase, the channel from the wireless device to the HAP is established as The channel from the IRS to the HAP is established as The channel from the legitimate wireless device to the IRS is established as The channel between the legitimate wireless device and the eavesdropping end is established as The channel between the IRS and the eavesdropper is established as

[0023] Preferably, in step 2.1, the entire process of transmission between the HAP and the user (wireless device) is as Figure 2 shown and includes:

[0024] The energy transfer phase;

[0025] The information transmission phase;

[0026] The secrecy rate;

[0027] The optimization objective.

[0028] Preferably, in step 2.1, during the energy transfer phase, the received signal of the legitimate wireless device is:

[0029]

[0030] where and are the Gaussian transmission distortion noises at the transmitter and receiver respectively;

[0031] The energy collected at the legitimate user can be expressed as:

[0032]

[0033] where η ∈ [0, 1] represents the energy conversion efficiency;

[0034] Information transmission phase: After experiencing the energy transmission phase, the legitimate wireless device transmits confidential information to the HAP during the information transmission phase, and the received information is:

[0035]

[0036] where s I is the confidential signal generated at the wireless device, and are the Gaussian transmission distortion noises at the transmitter and receiver during the information transmission phase, respectively;

[0037] Confidential rate: The information eavesdropped at the eavesdropper is:

[0038]

[0039] The confidential rate of the entire system is:

[0040] R = τ1[R U -R E +

[0041] where R U = log2(1 + γ U ), R E = log2(1 + γ E );

[0042]

[0043] Optimization objective: By jointly optimizing the HAP energy beamforming vector w, the IRS energy reflection coefficient ξ, and the information reflection coefficient ψ, the optimization problem is as follows:

[0044] P1:

[0045] s.t. ||w|| 2 ≤ P max

[0046]

[0047] τ0 + τ1 = 1

[0048] 0 ≤ τ k ≤ 1, k ∈ {0, 1}

[0049] Preferably: In step 2.2, by introducing auxiliary variables, the original problem is transformed into a series of convex optimization sub-problems, and the original variables are recovered using the Gaussian randomization method, and finally convergence is achieved.

[0050] ​Preferably, in step 2.2, an auxiliary variable p = [p1, p2, p3, p4] is introduced. T The objective function is relaxed, and the objective function satisfies R U ≥ p1 - p2 and R E ≤ p3 - p4. Problem P1 can be transformed into the following problem:

[0051] P2:

[0052] s.t. ||w|| 2 ≤ P max

[0053]

[0054] τ0 + τ1 = 1

[0055] 0 ≤ τ k ≤ 1, k ∈ {0, 1}

[0056] τ1 log2(Γ U (w, ξ, ψ) + τ0(1 + μ Et )(ξ H G A w)(ξ H G A w) H (ψ H G U )(ψ H G U ) H ≥ p1

[0057] τ1 log2(Γ U (w, ξ, ψ)) ≤ p2

[0058] τ1 log2(Γ E (w, ξ, ψ) + τ0(1 + μ Et )(ξ H G A w)(ξ H G A w) H (ψ H G E )(ψ H G E ) H ) ≤ p3

[0059] τ1 log2(Γ E (w, ξ, ψ)) ≥ p4

[0060] The steps to solve this problem are as follows: Input the convergence parameter ε and the iteration variable n, and iteratively update w, ξ, and ψ. The process is as follows:

[0061] 1) Initialization: In the first iteration, n = 0, and w is randomly generated (0) , ξ (0) and ψ (0) ;

[0062] 2) Optimize w given ξ and ψ: This sub - problem is a convex problem and is solved directly;

[0063] 3) Optimize ξ given w and ψ: This sub - problem is a convex problem and is solved directly, and ξ is recovered using Gaussian randomization;

[0064] 4) Optimize ψ given w and ξ: This sub - problem is a convex problem and is solved directly, and ψ is recovered using Gaussian randomization;

[0065] Repeat the above steps until convergence.

[0066] The present invention has the following beneficial effects:

[0067] The WPCN secure communication system provided by the present invention utilizes an IRS - assisted communication system and conducts robust design, thereby improving the secrecy rate of the system;

[0068] In the information transmission mode of the present invention, the beamforming technology in physical layer security is utilized, increasing the gap between the information transmission rates of legitimate users and eavesdropping users, and further ensuring the security of user - transmitted information. Brief Description of the Drawings

[0069] Figure 1 is a schematic diagram of an IRS - assisted WPCN secure communication robust optimization system.

[0070] Figure 2 is the flow chart of the proposed energy and information transmission.

[0071] Figure 3 is the variation of the secrecy rate with the hardware loss coefficient.

[0072] Figure 4 is the relationship between the secrecy rate and the HAP transmission power. Detailed Embodiments

[0073] To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be described below through specific embodiments shown in the drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the descriptions of well - known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0074] Detailed Embodiment 1: In combination with Figures 1-4To describe this embodiment, the physical layer security robust transmission scheme of the IRS-assisted wireless power communication system in this embodiment includes the following steps:

[0075] Step 1: Establishment of an IRS-assisted WPCN secure communication robust optimization system architecture;

[0076] As Figure 1 shown, assume that in a WPCN (Wireless Powered Communication Network), communication between an IRS-assisted hybrid base station and wireless devices is placed; the IRS-assisted wireless power communication system includes a HAP, wireless devices, eavesdroppers, and an IRS;

[0077] HAP (Hybrid Access Point): Responsible for energy transmission and information transmission; communicates with wireless devices through a wireless connection;

[0078] Wireless device (a legitimate wireless device with a single antenna and energy constraint, user): Communicates with the HAP through a wireless connection and receives energy from the HAP to maintain communication;

[0079] Eavesdropper (a single-antenna eavesdropper, eve): A single-antenna device used to eavesdrop on the communication between the HAP and wireless devices;

[0080] IRS (Intelligent Reflecting Surface): The IRS is equipped with reflecting units to enhance the signal transmission between the HAP and wireless devices; considering that there may be obstacles between the HAP and wireless devices, reflecting units are placed near the HAP and wireless devices respectively to overcome the obstruction of the obstacles;

[0081] During the energy transmission process, a channel is established between the HAP and the IRS, and then the energy is transmitted to the wireless device through the reflecting units of the IRS to optimize the transmission efficiency of energy and information. In the information transmission stage, the channel from the wireless device to the HAP is used for uplink information transmission, while the channel from the IRS to the HAP is used for downlink energy transmission; considering the channel characteristics between the wireless device and the eavesdropper, corresponding measures are taken to reduce the amount of useful information received by the eavesdropper and prevent the eavesdropper from receiving information;

[0082] In Step 1, the IRS-assisted wireless power communication system consists of a HAP with N antennas, a wireless device, an eavesdropper, and an IRS equipped with M reflecting units. In the two stages of the uplink and downlink, the reflection factors of the reflecting units of the IRS are different; N and M are natural numbers, T is the transpose, denotes the complex domain, and M×M denotes that the variable is a matrix of M×M dimensions;

[0083] The reflection coefficients in the two stages of the uplink and downlink can be expressed as and The reflection matrix can be respectively expressed as During the energy transmission process, the channel between the HAP and the IRS is established as The channel between the HAP and the wireless device is established as The channel between the IRS and the wireless device is established as During the information transmission phase, the channel from the wireless device to the HAP is established as The channel from the IRS to the HAP is established as The channel from the legitimate wireless device to the IRS is established as The channel between the legitimate wireless device and the eavesdropper is established as The channel between the IRS and the eavesdropper is established as Among them, w refers to the transmit beamforming vector of the HAP, and s E refers to the unit power energy signal symbol, refers to the additive white Gaussian noise AWGN at the eavesdropping user with noise variance

[0084] Step 2: Optimize the energy and information transmission processes between the HAP and the users, including the following steps:

[0085] Step 2.1: The energy and information transmission processes between the HAP and the users;

[0086] In Step 2.1, the entire process of transmission between the HAP and the users (wireless devices) is as Figure 2 shown and includes:

[0087] Energy transmission phase: The HAP (Hybrid Wireless Access Point) sends a radio frequency signal to the legitimate wireless device to provide energy, and this part of the energy is mainly used to maintain circuit operation and data transmission; during the energy transmission phase, the received signal of the legitimate wireless device is:

[0088]

[0089] Among them, and are the Gaussian transmission distortion noises at the transmitter and receiver respectively;

[0090] The energy collected at the legitimate user can be expressed as:

[0091]

[0092] Among them, η∈[0,1] represents the energy conversion efficiency, τ0 refers to the duration of the energy transmission phase, μ Et refers to the hardware impairment coefficient of the transmitter, and E refers to the expectation of calculating |y E | 2 ​​

[0093] Information transmission phase: After the energy transmission phase, the legitimate wireless device transmits the confidential information to the HAP in the information transmission phase. The received information is:

[0094]

[0095] where s I is the confidential signal generated at the wireless device, and are the Gaussian transmission distortion noises at the transmitter and receiver ends in the information transmission phase respectively. τ1 refers to the duration of the energy transmission phase, and Ω refers to the energy phase shift matrix of the IRS. refers to the additive white Gaussian noise at the legitimate user end in the WIT phase;

[0096] Secrecy rate: Since the eavesdropper's hardware is of high quality, the information eavesdropped at the eavesdropper is:

[0097]

[0098] The secrecy rate of the whole system is:

[0099] R = τ1[R U - R E +

[0100] where R U = log2(1 + γ U ), R E = log2(1 + γ E );

[0101]

[0102] where γ U refers to the signal-to-noise ratio of the legitimate user end, γ E refers to the signal-to-noise ratio of the eavesdropping end, R U refers to the information transmission rate of the legitimate user, R E refers to the information transmission rate of the eavesdropper, μ It refers to the hardware impairment coefficient of the transmitter end in the WIT phase, μ Ir refers to the hardware impairment coefficient of the receiver end, refers to the noise variance of the legitimate user end in the WIT phase, refers to the noise variance of the eavesdropping end in the WIT phase;

[0103] ​Optimization objective: Optimize the HAP energy beamforming vector, IRS energy reflection coefficient, and information reflection coefficient jointly to maximize the secrecy rate of the system; satisfy the base station transmit power and IRS reflection constraints; the optimization objective is to jointly optimize the HAP energy beamforming vector w, IRS energy reflection coefficient ξ, and information reflection coefficient ψ, and the optimization problem is as follows:

[0104] P1:

[0105] s.t. ||w|| 2 ≤ P max

[0106]

[0107] τ0 + τ1 = 1

[0108] 0 ≤ τ k ≤ 1, k ∈ {0, 1}

[0109] where, P max denotes the maximum transmit power of the HAP, ξ m denotes the m-th element in the IRS energy reflection coefficient vector, ψ m denotes the m-th element in the IRS information reflection coefficient vector, τ k denotes the time allocation factor between the energy transfer phase and the information transfer phase. If k takes 0, it is pure energy transfer; if k takes 1, it is pure information transfer;

[0110] Step 2.2: Optimization method:

[0111] By introducing auxiliary variables, the original problem is transformed into a series of convex optimization sub-problems, and the original variables are recovered using the Gaussian randomization method, finally achieving convergence; it can effectively handle complex optimization problems, and through the combination of convex optimization and Gaussian randomization, the stability and efficiency of the solution process are ensured;

[0112] In Step 2.2, introduce the auxiliary variable p = [p1, p2, p3, p4] T Relax the objective function, and the objective function satisfies R U ≥ p1 - p2 and R E ≤ p3 - p4, and problem P1 can be transformed into the following problem:

[0113] P2:

[0114] s.t. ||w|| 2 ≤ P max

[0115]

[0116] τ0 + τ1 = 1

[0117] 0 ≤ τ k ≤ 1, k ∈ {0, 1}

[0118] τ1log2(Γ U (w, ξ, ψ) + τ0(1 + μ Et )(ξ H G A w)(ξ H G A w) H (ψ H G U )(ψ H G U ) H ≥ p1

[0119] τ1log2(Γ U (w, ξ, ψ)) ≤ p2

[0120] τ1log2(Γ E (w, ξ, ψ) + τ0(1 + μ Et )(ξ H G A w)(ξ H G A w) H (ψ H G E )(ψ H G E ) H ) ≤ p3

[0121] τ1log2(Γ E (w, ξ, ψ)) ≥ p4

[0122] The steps to solve this problem are as follows: Input the convergence parameter ε and the iteration variable n. Then, iteratively update w, ξ, and ψ, and the process is as follows:

[0123] 1) Initialization: In the first iteration, n = 0, and randomly generate the initial variables w (0) , ξ (0) and ψ (0) ;

[0124] 2) Optimize w given ξ and ψ: This sub - problem is a convex problem and can be directly solved;

[0125] 3) Optimize ξ given w and ψ: This sub - problem is a convex problem and can be directly solved, and then use Gaussian randomization to recover ξ;

[0126] 4) Optimize ψ given w and ξ: This sub - problem is a convex problem and can be directly solved, and then use Gaussian randomization to recover ψ;

[0127] Repeat the above steps until convergence;

[0128] By using WPCN, the present invention can collect energy using wireless signals, featuring high reliability and controllability. And it considers information secure transmission from the perspective of the wireless channel; compared with traditional solutions, it can reduce the loss of manpower and material resources and effectively ensure information security; furthermore, it further considers the situation of hardware impairments existing in the actual RF components at the transmitter and receiver ends and conducts a robust optimization design for the system.

[0129] Step 3: Simulation and Results

[0130] Assume that the HAP, IRS, legitimate wireless device, and eavesdropping device are located at (0m, 0m), (5m, 0m), (10m, 2m), and (5m, 7m) respectively; the number of HAP antennas N = 16, the number of IRS reflection units M = 32; the energy collection coefficient is set to η = 1; the energy transmission and information transmission times are set to τ0 = 0.1 and τ1 = 0.9 respectively; the direct link channel is modeled using a Rayleigh channel, the path loss exponent is set to 3.5, and the path loss exponent of the cascaded channel related to the IRS is set to 2.2; for the channel related to the IRS, the Rician factor is set to β = 10, and the Rician factor of the direct link channel is set to β = 0; the large-scale fading coefficient PL0 = -30dB at the reference distance D0 = 1m; the maximum transmit power of the antenna is set to P max = 30dBm, and the noise power is set to The convergence tolerance is set to ε = 10 -4 ; Select the following benchmark algorithms: 1) RIS - Robust Design, 2) RIS - Non - Robust Design, 3) NonRIS - Robust Design, 4) NonRIS - Non - Robust Design;

[0131] As Figure 3 can be seen, according to our algorithm, the secrecy rate is higher than the other three schemes, which verifies the effectiveness of the proposed algorithm; this is because deploying IRS can increase the system spatial degrees of freedom; As Figure 4 can be seen, conducting robust design can significantly improve the secrecy rate, which is because robust design can well compensate for the losses brought by the hardware, and the effect is more obvious when the loss is large. Therefore, it can be foreseen that the algorithm proposed in the present invention is more applicable in actual communication systems;

[0132] The present invention is mainly applied in the context of the Internet of Things (IoT), considering the performance optimization scheme of the WPCN system; in terms of the system model, the present invention considers the secure communication problem in the presence of eavesdroppers and conducts joint optimization from two stages of energy transmission and information secure transmission; in terms of the optimization problem, the robust optimization of the present invention is reflected in considering the inevitable hardware impairments existing in the transceivers of the actual system.

[0133] It should be noted that in the above embodiments, as long as the technical solutions do not conflict, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, the present invention will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0134] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A robust transmission scheme for physical layer security of an IRS-assisted wireless power supply communication system, characterized in that: It includes the following steps: Step 1: Establishment of an IRS-assisted robust optimization system architecture for WPCN secure communication; In step 1, the IRS-assisted wireless power supply communication system consists of a A HAP with an antenna, a wireless device, an eavesdropper, and a mount The IRS consists of reflection units, and the reflection factors of the IRS reflection units are different in the uplink and downlink stages; The reflection coefficients of the two stages are respectively denoted as and , and the reflection matrices are respectively denoted as 、 ; The channel between the HAP and the IRS during the energy transmission process is established as , the channel between the HAP and the wireless device is established as , and the channel between the IRS and the wireless device is established as ; The channel establishment from the wireless device to the HAP during the information transmission phase is , the channel establishment from the IRS to the HAP is , the channel establishment from the wireless device to the IRS is ; the channel establishment between the wireless device and the eavesdropper is , the channel establishment between the IRS and the eavesdropper is ; ; Step 2: Optimize the energy and information transmission between the HAP and the user, including the following steps: Step 2.1: Energy and information transmission between the HAP and the user; Step 2.1 includes: Energy transmission phase; Information transmission phase; Secrecy rate; Optimization objective; Step 2.2: Optimization method: In Step 2.2, by introducing auxiliary variables, the original problem is transformed into a series of convex optimization sub-problems, and the original variables are recovered using the Gaussian randomization method until convergence is finally achieved; In step 2.2, introduce auxiliary variables Relax the objective function, which satisfies and , and problem is transformed into the following problem: The steps to solve this problem are as follows: input the convergence parameter and the iteration variable , and iteratively update , and , the process is as follows: 1) Initialization: In the first iteration, , randomly generate , and ; 2) Given and Optimize : This sub - problem is a convex problem and is solved directly; 3) Given and Optimize : This sub-problem is a convex problem and can be directly solved. Use Gaussian randomization to recover ; 4) Given and Optimize : This sub-problem is a convex problem. Solve it directly and use Gaussian randomization to recover ; Repeat the above steps until convergence.

2. The IRS-assisted physical layer secure robust transmission scheme for wireless power transfer communication system according to claim 1, wherein: In Step 1, the IRS-assisted wireless power transfer communication system includes a HAP, a wireless device, an eavesdropper, and an IRS; HAP: Responsible for energy transmission and information transmission; Communicates with the wireless device via a wireless connection; Wireless device: Communicates with the HAP via a wireless connection and receives energy from the HAP to maintain communication; Eavesdropper: A single-antenna device used to eavesdrop on the communication between the HAP and the wireless device; IRS: The IRS is equipped with reflection units for enhancing the signal transmission between the HAP and the wireless device; During the energy transmission process, a channel is established between the HAP and the IRS, and then the energy is transmitted to the wireless device through the IRS reflection unit. In the information transmission phase, the channel from the wireless device to the HAP is used for uplink information transmission, while the channel from the IRS to the HAP is used for downlink energy transmission.

3. The IRS-assisted physical layer secure robust transmission scheme for wireless power transfer communication system according to claim 2, wherein: In Step 2.1, during the energy transmission phase, the received signal of the wireless device is: Among them, and are the Gaussian transmission distortion noises of the transmitting end and the receiving end respectively; The energy collected at the user is expressed as: wherein represents the energy conversion efficiency; Information transmission phase: After experiencing the energy transmission phase, the wireless device transmits confidential information to the HAP in the information transmission phase, and the received information is: Among them, is a confidential signal generated at the wireless device, and are the Gaussian transmission distortion noises at the transmitter and the receiver respectively during the information transmission phase; Secrecy rate: The information eavesdropped at the eavesdropper is: ； The secrecy rate of the entire system is: Among them, , ; Optimization objective: Joint HAP energy beamforming vector , IRS energy reflection coefficient and information reflection coefficient , the optimization problem is as follows:

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