Intelligent reflecting surface auxiliary challenge response physical layer authentication method and device

Abstract

The invention provides an intelligent reflector auxiliary challenge response physical layer authentication method and device, and the method is applied to a base station, and comprises the steps: transmitting a pilot signal to a user side through a target channel, so as to achieve the channel pre-sharing between the base station and the user side; under the condition that the transmitting power budget of the base station changes, a challenge signal is sent to the user side according to channel configuration information randomly selected from different pieces of channel configuration information; receiving an encryption response signal sent by the user side; and decrypting the encrypted response signal according to the randomly selected channel configuration information to obtain decrypted information, and performing identity authentication on the user side according to the decrypted information and the randomly selected channel configuration to obtain an authentication result. According to the method disclosed by the invention, the channel configuration assisted by the intelligent reflecting surface is used as the pre-shared key, so that the authentication problem caused by noise interference and inaccurate channel estimation in the prior art is effectively solved, and the authentication efficiency and the transmission security of the wireless communication physical layer are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless communication physical layer security transmission, and in particular to an intelligent reflective surface assisted challenge response physical layer authentication method and device. Background Art

[0002] With the rapid development of wireless communication technology and the approaching 6G era, the security requirements for mobile communication networks continue to increase.

[0003] Especially in the complex environment of wireless signal propagation, traditional cryptography-based authentication methods, such as Public Key Infrastructure (PKI) and symmetric key encryption, have some shortcomings in complex wireless environments. For example, these methods require a lot of computing resources and face the difficulties of brute force cracking and key management. Moreover, with the increase in the number of communication devices and the scale of the network, the authentication efficiency and security of these methods are difficult to meet future needs.

[0004] In the related art, Physical Layer Authentication (PLA) uses the inherent physical characteristics of the wireless signal propagation process to design an authentication scheme that does not require a complex encryption mechanism. For example, the physical characteristics include Channel State Information (CSI) and Received Signal Strength (RSS). However, the existing PLA method is easily affected by noise and interference in the Non-Line-of-Sight (NLOS) transmission scenario, resulting in inaccurate channel estimation and reducing the authentication efficiency of the wireless communication system. Moreover, when the channel conditions of the eavesdropper and the legitimate user are similar, PLA has difficulty in effectively distinguishing between the legitimate user and the eavesdropper, thereby increasing the success rate of the attack and resulting in low security of wireless communication transmission. Summary of the invention

[0005] The present invention provides an intelligent reflective surface assisted challenge response physical layer authentication method and device, which are used to solve the problem that the PLA method used in the prior art is easily affected by noise and interference in a non-line-of-sight (NLOS) transmission scenario, which reduces the authentication efficiency of the wireless communication system, and the PLA is difficult to effectively distinguish between legitimate users and eavesdroppers, thereby increasing the attack success rate, resulting in low wireless communication transmission security. The method improves the wireless communication physical layer authentication efficiency and transmission security.

[0006] The present invention provides an intelligent reflective surface assisted challenge response physical layer authentication method, which is applied to a base station and includes: Sending a pilot signal to a user terminal through a target channel to achieve channel pre-sharing between the base station and the user terminal; wherein different channel configuration information of the target channel is determined based on a transmit power budget of the base station and a reflection matrix of an intelligent reflecting surface IRS; When the transmit power budget of the base station changes, sending a challenge signal to the user terminal according to the channel configuration information randomly selected from the different channel configuration information; receiving an encrypted response signal sent by the user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; and the target channel configuration information is determined based on the pilot signal; The encrypted response signal is decrypted according to the randomly selected channel configuration information to obtain decrypted information, and identity authentication is performed on the user terminal according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

[0007] According to a smart reflective surface assisted challenge response physical layer authentication method provided by the present invention, the target channel is modeled by the following formula: ; in, and are the channels of Alice-IRS and IRS-Bob respectively, is the reflection matrix of IRS, is the base station power, for noise; is the vector signal sent by the legitimate user Alice, is the signal received at the base station Bob, represents the complex channel coefficient between the base station Bob and the IRS unit; H is the conjugate transpose of the matrix.

[0008] According to a smart reflective surface assisted challenge response physical layer authentication method provided by the present invention, the transmission power budget of the base station is optimized through the following steps: Taking different transmission powers of the base station and the reflection matrix of the IRS as decision variables, constructing an optimization problem with maximizing the communication success rate of the user end and minimizing the success rate of the eavesdropper as the optimization goal; and solving the optimization problem to obtain an optimized transmission power budget; The optimization problem is expressed as follows: ; in, is the transmission power of the base station, is the reflection matrix of IRS, is the communication success rate of the user end, is the communication success rate of the eavesdropper; The constraints of the optimization problem are expressed as follows: ; Among them, || || is the norm operation, is the transmit power budget, n is the number of reflection units.

[0009] According to a smart reflective surface assisted challenge response physical layer authentication method provided by the present invention, the transmission power budget of the base station is also optimized through the following steps: The transmission power budget is adjusted according to at least one of the real-time communication load and the environmental noise level of the target channel by adopting a power dynamic allocation strategy to obtain an optimized transmission power budget.

[0010] According to an intelligent reflective surface assisted challenge response physical layer authentication method provided by the present invention, the different channel configuration information of the target channel is also determined based on the transmit power budget of the base station, the reflection matrix of the intelligent reflective surface IRS and the physical layer characteristic parameters; The physical layer characteristic parameter is determined by at least one of received signal strength and signal arrival time difference.

[0011] The present invention also provides an intelligent reflective surface assisted challenge response physical layer authentication method, which is applied to a user end and includes: Receive a pilot signal sent by a base station through a target channel; wherein different channel configuration information of the target channel is determined based on the transmit power budget of the base station and the reflection matrix of the intelligent reflection surface IRS

[0012] Determine target channel configuration information according to the pilot signal; receiving a challenge signal sent by the base station; Decoding the challenge signal based on the target channel configuration information to obtain decoded information, and encrypting the decoded information according to the channel configuration information randomly selected from the different channel configuration information to generate an encrypted response signal; The encrypted response signal is sent to the base station so that the base station can perform identity authentication on the user terminal.

[0013] The present invention also provides an intelligent reflective surface assisted challenge response physical layer authentication device, comprising: A first sending module is used to send a pilot signal to a user terminal through a target channel to realize channel pre-sharing between a base station and a user terminal; wherein different channel configuration information of the target channel is determined based on a transmit power budget of the base station and a reflection matrix of an intelligent reflecting surface IRS; A second sending module is used to send a challenge signal to the user terminal according to the channel configuration information randomly selected from the different channel configuration information when the transmission power budget of the base station changes; A first receiving module is configured to receive an encrypted response signal sent by the user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; and the target channel configuration information is determined based on the pilot signal; The decryption and authentication module is used to decrypt the encrypted response signal according to the randomly selected channel configuration information to obtain decrypted information, and to perform identity authentication on the user terminal according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

[0014] The present invention also provides an intelligent reflective surface assisted challenge response physical layer authentication device, comprising: The second receiving module is used to receive the pilot signal sent by the base station through the target channel; wherein the different channel configuration information of the target channel is determined based on the transmit power budget of the base station and the reflection matrix of the intelligent reflecting surface IRS

[0015] A processing module, configured to determine target channel configuration information according to the pilot signal; A third receiving module, used to receive the challenge signal sent by the base station; an encryption module, configured to decode the challenge signal based on the target channel configuration information to obtain decoded information, and encrypt the decoded information according to the channel configuration information randomly selected from the different channel configuration information to generate an encrypted response signal; The third sending module is used to send the encrypted response signal to the base station so that the base station can perform identity authentication on the user terminal.

[0016] 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 smart reflective surface assisted challenge response physical layer authentication method as described above is implemented.

[0017] The present invention also 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 smart reflective surface-assisted challenge-response physical layer authentication method as described in any one of the above is implemented.

[0018] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any of the above-mentioned smart reflective surface-assisted challenge-response physical layer authentication methods.

[0019] The intelligent reflective surface assisted challenge response physical layer authentication method and device provided by the present invention, when the transmission power budget of the base station changes, sends a challenge signal to the user terminal according to channel configuration information randomly selected from different channel configuration information under the condition of realizing channel pre-sharing between the base station and the user terminal, decrypts the encrypted response signal fed back by the user terminal to obtain decrypted information, and then authenticates the user terminal according to the decrypted information and the randomly selected channel configuration; the IRS-assisted channel configuration is used as the pre-shared key, which effectively solves the authentication problem caused by noise interference and inaccurate channel estimation in the prior art, and improves the wireless communication physical layer authentication efficiency and transmission security. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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.

[0021] Figure 1 This is one of the flow charts of the reflective surface assisted challenge response physical layer authentication method provided by the present invention.

[0022] Figure 2 It is a schematic diagram of the interaction between a base station, a legitimate user and an eavesdropper in the IRS-assisted security authentication scenario provided by the present invention.

[0023] Figure 3 The second flowchart of the reflective surface assisted challenge response physical layer authentication method provided by the present invention.

[0024] Figure 4 One of the structural schematic diagrams of the reflective surface assisted challenge response physical layer authentication device provided by the present invention.

[0025] Figure 5 The third flow chart of the reflective surface assisted challenge response physical layer authentication method provided by the invention.

[0026] Figure 6The second structural diagram of the reflective surface assisted challenge response physical layer authentication device provided by the invention.

[0027] Figure 7 A schematic structural diagram of an electronic device provided by the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Combine the following Figure 1-Figure 6 The present invention discloses a reflective surface assisted challenge response physical layer authentication method and device.

[0030] Figure 1 FIG. 1 is one of the flow charts of the reflective surface assisted challenge response physical layer authentication method provided by the present invention, such as Figure 1 As shown, the intelligent reflective surface assisted challenge response physical layer authentication method is applied to a base station and includes the following steps: Step 110: Send a pilot signal to the user terminal through the target channel to achieve channel pre-sharing between the base station and the user terminal; wherein different channel configuration information of the target channel is determined based on the transmission power budget of the base station and the reflection matrix of the intelligent reflecting surface IRS.

[0031] It should be noted that in wireless communication systems, especially in cellular networks and wireless LANs (such as LTE, 5G and Wi-Fi), pilot signals are pre-known signals that the receiving end can use to estimate the characteristics of the wireless channel, for example, factors such as multipath propagation, fading and interference. In 5G, pilot signals include DM-RS (Demodulation Reference Signal) and CSI-RS (Channel State Information Reference Signal), which are used for channel estimation, demodulation and feedback of channel state information.

[0032] In this embodiment, the channel configuration information includes channel definition, channel selection, automatic channel selection, manual channel selection, channel scanning, channel configuration in an LTE system, Wi-Fi channel or 5G NR channel configuration, etc.

[0033] In this step, the base station sends a pilot signal to the user end (legitimate user). The user end can estimate the relevant configuration information of the current target channel based on the pilot signal and store it as a shared key for subsequent decryption, encryption or generation of corresponding signals for authentication of the signals sent by the base station.

[0034] In this embodiment, the target channel is a pre-authenticated channel; specifically, the target channel is modeled by the following formula: ; in, and They are the channels between the user end and IRS (Intelligent Reflecting Surface) and the IRS and base station. is the reflection matrix of IRS, is the base station power, for noise; is the vector signal sent by the legitimate user Alice, is the signal received at the base station Bob, represents the complex channel coefficient between the base station Bob and the IRS unit; H is the conjugate transpose of the matrix.

[0035] Figure 2 is a schematic diagram of the interaction between the base station, the legitimate user and the eavesdropper in the IRS-assisted security authentication scenario provided by the present invention. Figure 2 In the embodiment shown, in an IRS-assisted security authentication system (IRS is composed of multiple adjustable reflection units), three entities are included: a legitimate user Alice, a base station Bob, and an eavesdropper Eve. As shown in the figure, obstacles block the direct link from Alice and Eve to Bob, and the channel model of the current communication system is a Rayleigh fading channel; Alice, Bob, and Eve each have an antenna, and the IRS is a uniform linear array of order N, consisting of N 2 The channels between Alice-IRS, IRS-Bob, and Eve-IRS are modeled as Rice fading channel models. These channels can be expressed as h ra , h br , h re .

[0036] This embodiment generates an optimal random IRS reflection matrix configuration according to different transmit power budgets, thereby ensuring authentication security while improving communication efficiency.

[0037] In some embodiments, a machine learning-based optimization algorithm, a genetic algorithm, or a particle swarm algorithm may also be used to generate an optimal configuration to adapt to different wireless communication scenarios and optimize authentication performance.

[0038] Step 120: When the transmit power budget of the base station changes, a challenge signal is sent to the user terminal according to channel configuration information randomly selected from different channel configuration information.

[0039] In this step, the base station implements random channel configuration by changing different transmission power budgets and sending a challenge signal to the user end by randomly selecting channel configurations. This randomness makes it impossible for the eavesdropper Eve to attack through a fixed configuration even if she can partially obtain channel information, thereby significantly reducing the success rate of man-in-the-middle attacks (MitM). In addition, even if the eavesdropper is fully aware of the shared channel configuration and the number of IRS units, the above-mentioned random channel configuration method can also reduce the success rate of the attack.

[0040] In this embodiment, multiple IRS reflection matrix configurations are generated according to the power budget of the base station. These configurations are calculated by the base station according to the current channel state information (CSI) and randomly selected during the authentication process as the basis for challenge-response authentication. Each IRS configuration corresponds to different channel characteristics, making it difficult for an eavesdropper to obtain complete channel information by guessing.

[0041] In this embodiment, the user end decodes the challenge signal according to the stored pre-shared channel information, and generates an encrypted response according to the unique channel configuration.

[0042] Step 130, receiving an encrypted response signal sent by the user end; wherein the encrypted response signal is generated based on the user end encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user end decoding according to the target channel configuration information; the target channel configuration information is determined based on the pilot signal.

[0043] In this step, the user end decodes the challenge signal according to the stored pre-shared channel information and generates an encrypted response according to the unique channel configuration.

[0044] Specifically, in the target channel N, i different base station transmission power budgets correspond to i channel configuration information. After the base station sends a pilot signal to the user terminal through the target channel N, the user terminal can store i channel configuration information, that is, i different key information; when the base station sends a challenge signal to the user terminal through the j-th channel configuration information, the user terminal first decodes the challenge signal through the stored key information, and then uses the j-th channel configuration information to encrypt the decoded information to generate a response for authentication, that is, an encrypted response signal; finally, the encrypted response signal is sent to the base station for authentication.

[0045] Step 140: decrypt the encrypted response signal according to the randomly selected channel configuration information to obtain decrypted information, and authenticate the user terminal according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

[0046] In this embodiment, it is assumed that the randomly selected channel configuration information is the j-th channel configuration information corresponding to the current transmission power budget in the target channel N; after the base station receives the encrypted response signal, it decrypts the encrypted response signal according to the j-th channel configuration information in the current channel to obtain the decrypted information, and the base station estimates the decrypted data to obtain the channel information estimated by the base station.

[0047] In this embodiment, the base station authenticates the legitimacy of the identity of the user terminal according to the IRS channel configuration and the received response information; the authentication method includes a hypothesis testing method.

[0048] Specifically, the legality is judged through the hypothesis test shown in the following formula: ; in, is the channel information estimated by the base station, is the assumed channel information, which can be calculated through the j-th channel configuration information. A threshold is set to determine whether the user is a legitimate user or an eavesdropper.

[0049] In this embodiment, if , indicating that the decrypted information of the base station matches the above-mentioned encrypted response signal, then the authentication of the legitimacy of the user terminal identity is successful and the user terminal is deemed to be legitimate; otherwise, the authentication fails.

[0050] The present invention provides an intelligent reflective surface assisted challenge response physical layer authentication method. Under the condition of realizing channel pre-sharing between a base station and a user terminal, when the transmission power budget of the base station changes, a challenge signal is sent to the user terminal according to channel configuration information randomly selected from different channel configuration information, and an encrypted response signal fed back by the user terminal is decrypted to obtain decrypted information, and then the user terminal is authenticated according to the decrypted information and the randomly selected channel configuration; the IRS-assisted channel configuration is used as a pre-shared key, which effectively solves the authentication problem caused by noise interference and inaccurate channel estimation in the prior art, and improves the authentication efficiency and transmission security of the wireless communication physical layer.

[0051] In some embodiments, due to the limited power budget of the communication system in some wireless communication scenarios, problems such as reduced coverage, decreased signal quality, reduced connection stability, reduced data transmission rate, increased energy consumption, and limited device performance may arise.

[0052] To solve the above problems, the transmission power budget of the base station is optimized through the following steps: taking the different transmission powers of the base station and the reflection matrix of the IRS as decision variables, constructing an optimization problem with the optimization goal of maximizing the communication success rate of the user end and minimizing the success rate of the eavesdropper; and solving the optimization problem to obtain the optimized transmission power budget; the optimization problem is expressed by the following formula: ; in, is the transmission power of the base station, is the reflection matrix of IRS, is the communication success rate of the user side, is the communication success rate of the eavesdropper; the constraints of the optimization problem are expressed by the following formula: ; Among them, || || is the norm operation, is the transmit power budget, n is the number of reflection units.

[0053] In this embodiment, by setting the above constraints and adjusting the transmission power of the base station, the optimal solution corresponding to the above optimization problem is solved, so as to maximize the communication success rate of legitimate users and minimize the success rate of eavesdroppers, thereby ensuring higher authentication efficiency and security under limited power budget conditions; the above adaptive power adjustment mechanism not only optimizes resource utilization, but also further improves the robustness of authentication.

[0054] The present invention provides an intelligent reflective surface assisted challenge response physical layer authentication method, which generates an optimal random IRS reflection matrix configuration through different transmission power budgets, thereby improving communication efficiency while ensuring authentication security.

[0055] In some embodiments, the transmit power budget of the base station is further optimized by adopting a power dynamic allocation strategy to adjust the transmit power budget according to at least one of the real-time communication load of the target channel and the environmental noise level to obtain an optimized transmit power budget.

[0056] In this embodiment, a common power budget adjustment scheme is to optimize the fixed power of the base station. For multi-user scenarios, this embodiment can also adopt a power dynamic allocation strategy to adjust the base station's transmit power and power budget according to the real-time communication load or environmental noise level, thereby improving the flexibility of optimizing the transmit power budget in multi-user scenarios.

[0057] In this embodiment, the power dynamic allocation strategy may include a power control algorithm, multiple access technology, multi-backhaul link selection and power allocation, dynamic resource configuration or queuing theory analysis technology.

[0058] Specifically, the transmission power is dynamically adjusted according to the strength of the received signal through the power control algorithm. For example, the power control algorithm based on the signal-to-interference ratio (SIR) determines the appropriate transmission power by measuring the signal strength and the degree of interference to achieve the best communication quality and system performance; the non-orthogonal multiple access (NOMA) technology allows different users to reuse the same time, frequency, and space resources through power reuse or feature codebook design to improve spectrum efficiency; the multi-backhaul link selection and power allocation technology enables data packets to select appropriate backhaul links and power for transmission according to their service characteristics and link conditions, effectively improving the transmission rate of the network; the bandwidth and power configuration of the base station are optimized through dynamic resource allocation technology to maximize the energy efficiency of the wireless communication network under the given resource allocation constraints; in the joint optimization of multi-backhaul link selection and power allocation, the transmission delay of the data packet on the small base station sub-queue is analyzed through the queuing theory analysis technology, with the maximization of the delay tolerance elasticity value as the optimization goal.

[0059] The present invention provides an intelligent reflective surface-assisted challenge response physical layer authentication method, which adopts a dynamic power allocation strategy to adjust the transmission power budget according to at least one of the real-time communication load of the target channel and the environmental noise level, thereby realizing dynamic adjustment of the base station power budget and improving the flexibility of multi-user scenario authentication.

[0060] In some embodiments, different channel configuration information of the target channel is also determined based on the base station's transmit power budget, the reflection matrix of the intelligent reflecting surface IRS, and the physical layer characteristic parameters; wherein the physical layer characteristic parameters are determined by at least one of the received signal strength and the signal arrival time difference.

[0061] In this embodiment, authentication security is improved by adding additional physical layer characteristics (such as received signal strength, signal arrival time difference) as auxiliary information.

[0062] Specifically, the user end-IRS, IRS-base station channel, IRS reflection matrix, base station power, noise, received signal strength and are used as channel modeling parameters. As the independent variable, Mathematical modeling is performed for the dependent variable to obtain a new target channel model, and then different channel configuration information is output through the model for different scenarios and physical layer characteristic parameters.

[0063] The present invention provides an intelligent reflector-assisted challenge-response physical layer authentication method, which constructs a target channel parameter model through the transmission power budget of the base station, the reflection matrix of the intelligent reflector IRS and the physical layer characteristic parameters to obtain different channel configuration information. This multi-feature joint authentication mechanism further enhances the robustness and anti-attack capability of the system.

[0064] In some embodiments, since the multi-layer IRS system can provide more accurate channel optimization in complex scenarios, and multi-base station collaboration can enhance the accuracy and reliability of authentication; this embodiment can also further improve the controllability of channel conditions and the security of authentication by introducing a multi-layer IRS or multi-base station collaborative authentication mechanism.

[0065] Figure 3 The second flow chart of the reflective surface assisted challenge response physical layer authentication method provided by the present invention is as follows: Figure 3 In the illustrated embodiment, in an IRS-assisted security authentication system (IRS is composed of multiple adjustable reflection units, which can dynamically adjust the phase and amplitude of the signal), three entities are included: a legitimate user Alice, a base station Bob, and an eavesdropper Eve; Alice and Bob perform physical layer authentication through IRS, while Eve attempts to disrupt the authentication process through eavesdropping attacks. The authentication process of this embodiment is as follows: Step 1: Channel pre-sharing, Bob appropriately selects a pre-verified channel to send a pilot signal to Alice; Step 2: Random configuration, Bob changes different transmit power budgets and sends a challenge to Alice by randomly selecting a channel configuration; Alice decodes the signal using the pre-shared channel information and generates an encrypted response based on the unique channel configuration; Step 3: Challenge-Response Authentication, Alice sends a message, and Bob decrypts the message from the received signal to represent Alice's response part of the authentication process; Step 4: Channel check, Bob verifies Alice's identity based on the IRS channel configuration and the received response information; if Bob's decrypted information matches step 2 (expected response), the authentication is successful and Alice is considered legitimate; otherwise, the authentication fails.

[0066] The following is a description of the intelligent reflective surface assisted challenge response physical layer authentication device provided by the present invention. The intelligent reflective surface assisted challenge response physical layer authentication device described below and the intelligent reflective surface assisted challenge response physical layer authentication method described above can be referenced to each other.

[0067] Figure 4 One of the structural schematic diagrams of the reflective surface assisted challenge response physical layer authentication device provided by the present invention is as follows: Figure 4 As shown, the device includes: a first sending module 410 , a second sending module 420 , a first receiving module 430 and a decryption and authentication module 440 .

[0068] The first sending module 410 is used to send a pilot signal to the user terminal through the target channel to realize channel pre-sharing between the base station and the user terminal; wherein different channel configuration information of the target channel is determined based on the transmission power budget of the base station and the reflection matrix of the intelligent reflection surface IRS; The second sending module 420 is used to send a challenge signal to the user terminal according to the channel configuration information randomly selected from different channel configuration information when the transmission power budget of the base station changes; The first receiving module 430 is used to receive an encrypted response signal sent by a user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; the target channel configuration information is determined based on the pilot signal; The decryption and authentication module 440 is used to decrypt the encrypted response signal according to the randomly selected channel configuration information to obtain decrypted information, and perform identity authentication on the user terminal according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

[0069] The present invention provides an intelligent reflective surface assisted challenge response physical layer authentication device. Under the condition of realizing channel pre-sharing between a base station and a user terminal, when the transmission power budget of the base station changes, a challenge signal is sent to the user terminal according to channel configuration information randomly selected from different channel configuration information, and an encrypted response signal fed back by the user terminal is decrypted to obtain decrypted information, and then the user terminal is authenticated according to the decrypted information and the randomly selected channel configuration; the IRS-assisted channel configuration is used as a pre-shared key, which effectively solves the authentication problem caused by noise interference and inaccurate channel estimation in the prior art, and improves the wireless communication physical layer authentication efficiency and transmission security.

[0070] Figure 5 The third flow chart of the reflective surface assisted challenge response physical layer authentication method provided by the invention is as follows: Figure 5 As shown, the intelligent reflective surface assisted challenge response physical layer authentication method, applied to the user end, includes the following steps: Step 510: Receive a pilot signal sent by the base station through a target channel; wherein different channel configuration information of the target channel is determined based on a transmit power budget of the base station and a reflection matrix of an intelligent reflecting surface IRS.

[0071] In this step, the base station sends a pilot signal to the user end (legitimate user), and the user end can estimate the relevant configuration information of the current target channel according to the pilot signal.

[0072] In this embodiment, the target channel is a pre-authenticated channel; specifically, the target channel is modeled by the following formula: ; in, and They are the channels of user terminal-IRS and IRS-base station respectively. is the reflection matrix of IRS, is the base station power, for noise; is the vector signal sent by the legitimate user Alice, is the signal received at the base station Bob, represents the complex channel coefficient between the base station Bob and the IRS unit; H is the conjugate transpose of the matrix.

[0073] This embodiment generates an optimal random IRS reflection matrix configuration according to different transmit power budgets, thereby ensuring authentication security while improving communication efficiency.

[0074] In some embodiments, a machine learning-based optimization algorithm, a genetic algorithm, or a particle swarm algorithm may also be used to generate an optimal configuration to adapt to different wireless communication scenarios and optimize authentication performance.

[0075] Step 520: Determine target channel configuration information according to the pilot signal.

[0076] In this step, the channel configuration information includes channel definition, channel selection, automatic channel selection, manual channel selection, channel scanning, channel configuration in LTE system, Wi-Fi channel or 5G NR channel configuration, etc.

[0077] In this embodiment, the user terminal may create a shared key storage according to the channel configuration information obtained through analysis, which is used for subsequent decryption or encryption of a signal sent by the base station or generation of a corresponding signal for authentication.

[0078] Step 530: Receive a challenge signal sent by the base station.

[0079] In this step, the base station implements random channel configuration by changing different transmission power budgets and sending a challenge signal to the user end by randomly selecting channel configurations. This randomness makes it impossible for the eavesdropper Eve to attack through a fixed configuration even if she can partially obtain channel information, thereby significantly reducing the success rate of man-in-the-middle attacks (MitM). In addition, even if the eavesdropper is fully aware of the shared channel configuration and the number of IRS units, the above-mentioned random channel configuration method can also reduce the success rate of the attack.

[0080] In this embodiment, multiple IRS reflection matrix configurations are generated according to the power budget of the base station. These configurations are calculated by the base station according to the current channel state information (CSI) and randomly selected during the authentication process as the basis for challenge-response authentication. Each IRS configuration corresponds to different channel characteristics, making it difficult for an eavesdropper to obtain complete channel information by guessing.

[0081] Step 540: decode the challenge signal based on the target channel configuration information to obtain decoded information, and encrypt the decoded information according to channel configuration information randomly selected from different channel configuration information to generate an encrypted response signal.

[0082] In this step, the user end decodes the challenge signal according to the stored pre-shared channel information and generates an encrypted response according to the unique channel configuration.

[0083] Specifically, in the target channel N, i different base station transmission power budgets correspond to i channel configuration information. After the base station sends a pilot signal to the user terminal through the target channel N, the user terminal can store i channel configuration information, that is, i different key information; when the base station sends a challenge signal to the user terminal through the j-th channel configuration information, the user terminal first decodes the challenge signal through the stored key information, and then uses the j-th channel configuration information to encrypt the decoded information to generate a response for authentication, that is, an encrypted response signal; finally, the encrypted response signal is sent to the base station for authentication.

[0084] Step 550: Send an encrypted response signal to the base station so that the base station can authenticate the user terminal.

[0085] In this step, the user end encrypts the decoded information again according to the randomly selected channel configuration information, and then sends the encrypted response signal to the base station, so that the base station can authenticate the legitimacy of the identity of the user end according to the IRS channel configuration and the received response information.

[0086] In this embodiment, the process of the base station verifying the legitimacy of the identity of the user terminal through hypothesis verification is as described in the embodiment corresponding to the above step 140, and will not be repeated in this embodiment.

[0087] The present invention provides an intelligent reflective surface-assisted challenge-response physical layer authentication method. Under the condition of realizing channel pre-sharing between a base station and a user terminal, the user terminal decrypts a challenge signal sent by the base station according to the pre-shared channel configuration information to obtain decrypted information, and then encrypts the decrypted information again according to the channel configuration information randomly selected by the base station to obtain an encrypted response signal, and sends it to the base station for the base station to authenticate the user terminal. This realizes efficient challenge-response physical layer authentication, reduces the success rate of eavesdropper attacks, and improves authentication security.

[0088] The following is a description of the intelligent reflective surface assisted challenge response physical layer authentication device provided by the present invention. The intelligent reflective surface assisted challenge response physical layer authentication device described below and the intelligent reflective surface assisted challenge response physical layer authentication method described above can be referenced to each other.

[0089] Figure 6 The second structural diagram of the reflective surface assisted challenge response physical layer authentication device provided by the invention is as follows: Figure 6 As shown, the device includes: a second receiving module 610, a processing module 620, a third receiving module 630, an encryption module 640 and a third sending module 650.

[0090] The second receiving module 610 is used to receive the pilot signal sent by the base station through the target channel; wherein the different channel configuration information of the target channel is determined based on the transmission power budget of the base station and the reflection matrix of the intelligent reflection surface IRS

[0091] A processing module 620, configured to determine target channel configuration information according to the pilot signal; The third receiving module 630 is used to receive the challenge signal sent by the base station; The encryption module 640 is used to decode the challenge signal based on the target channel configuration information to obtain decoded information, and encrypt the decoded information according to the channel configuration information randomly selected from the different channel configuration information to generate an encrypted response signal; The third sending module 650 is used to send an encrypted response signal to the base station so that the base station can perform identity authentication on the user terminal.

[0092] The present invention provides an intelligent reflective surface-assisted challenge-response physical layer authentication device. Under the condition of realizing channel pre-sharing between a base station and a user terminal, the user terminal decrypts a challenge signal sent by the base station according to the pre-shared channel configuration information to obtain decrypted information, and then encrypts the decrypted information again according to the channel configuration information randomly selected by the base station to obtain an encrypted response signal, and sends it to the base station for the base station to authenticate the user terminal. This realizes efficient challenge-response physical layer authentication, reduces the success rate of eavesdropper attacks, and improves authentication security.

[0093] Figure 7 is a schematic diagram of the structure of the electronic device provided by the present invention, such as Figure 7As shown, the electronic device may include: a processor (processor) 710 , a communication interface (Communications Interface) 720 , a memory (memory) 730 and a communication bus 740 , wherein the processor 710 , the communication interface 720 , and the memory 730 communicate with each other through the communication bus 740 . The processor 710 can call the logic instructions in the memory 730 to execute the intelligent reflective surface assisted challenge response physical layer authentication method, which is applied to the base station. The method includes: sending a pilot signal to the user terminal through the target channel to realize channel pre-sharing between the base station and the user terminal; wherein different channel configuration information of the target channel is determined based on the transmission power budget of the base station and the reflection matrix of the intelligent reflective surface IRS; when the transmission power budget of the base station changes, sending a challenge signal to the user terminal according to the channel configuration information randomly selected from the different channel configuration information; receiving an encrypted response signal sent by the user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; the target channel configuration information is determined based on the pilot signal; the encrypted response signal is decrypted according to the randomly selected channel configuration information to obtain the decrypted information, and the user terminal is authenticated according to the decrypted information and the randomly selected channel configuration to obtain the authentication result.

[0094] Alternatively, an intelligent reflecting surface assisted challenge response physical layer authentication method is executed and applied to a user terminal, the method comprising: receiving a pilot signal sent by a base station through a target channel; wherein different channel configuration information of the target channel is determined based on a transmission power budget of the base station and a reflection matrix of the intelligent reflecting surface IRS; determining the target channel configuration information according to the pilot signal; receiving a challenge signal sent by the base station; decoding the challenge signal based on the target channel configuration information to obtain decoded information, and encrypting the decoded information according to channel configuration information randomly selected from different channel configuration information to generate an encrypted response signal; and sending the encrypted response signal to the base station for the base station to authenticate the user terminal.

[0095] In addition, the logic instructions in the above-mentioned memory 730 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 can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several 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, etc. Various media that can store program codes.

[0096] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the intelligent reflective surface assisted challenge response physical layer authentication method provided by the above methods, which is applied to a base station, and the method includes: sending a pilot signal to a user terminal through a target channel to realize channel pre-sharing between the base station and the user terminal; wherein different channel configuration information of the target channel is determined based on the transmission power budget of the base station and the reflection matrix of the intelligent reflective surface IRS; when the transmission power budget of the base station changes, a challenge signal is sent to the user terminal according to the channel configuration information randomly selected from different channel configuration information; receiving an encrypted response signal sent by the user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; the target channel configuration information is determined based on the pilot signal; the encrypted response signal is decrypted according to the randomly selected channel configuration information to obtain decrypted information, and the user terminal is authenticated according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

[0097] Alternatively, an intelligent reflecting surface assisted challenge response physical layer authentication method is executed and applied to a user terminal, the method comprising: receiving a pilot signal sent by a base station through a target channel; wherein different channel configuration information of the target channel is determined based on a transmission power budget of the base station and a reflection matrix of the intelligent reflecting surface IRS; determining the target channel configuration information according to the pilot signal; receiving a challenge signal sent by the base station; decoding the challenge signal based on the target channel configuration information to obtain decoded information, and encrypting the decoded information according to channel configuration information randomly selected from different channel configuration information to generate an encrypted response signal; and sending the encrypted response signal to the base station for the base station to authenticate the user terminal.

[0098] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the intelligent reflector-assisted challenge response physical layer authentication method provided by the above-mentioned methods, and is applied to a base station, the method comprising: sending a pilot signal to a user terminal through a target channel to realize channel pre-sharing between the base station and the user terminal; wherein different channel configuration information of the target channel is determined based on the transmission power budget of the base station and the reflection matrix of the intelligent reflector surface IRS; when the transmission power budget of the base station changes, sending a challenge signal to the user terminal according to channel configuration information randomly selected from different channel configuration information; receiving an encrypted response signal sent by the user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; the target channel configuration information is determined based on the pilot signal; the encrypted response signal is decrypted according to the randomly selected channel configuration information to obtain decrypted information, and the user terminal is authenticated according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

[0099] Alternatively, an intelligent reflecting surface assisted challenge response physical layer authentication method is executed and applied to a user terminal, the method comprising: receiving a pilot signal sent by a base station through a target channel; wherein different channel configuration information of the target channel is determined based on a transmission power budget of the base station and a reflection matrix of the intelligent reflecting surface IRS; determining the target channel configuration information according to the pilot signal; receiving a challenge signal sent by the base station; decoding the challenge signal based on the target channel configuration information to obtain decoded information, and encrypting the decoded information according to channel configuration information randomly selected from different channel configuration information to generate an encrypted response signal; and sending the encrypted response signal to the base station for the base station to authenticate the user terminal.

[0100] 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.

[0101] 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.

[0102] 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. An intelligent reflective surface assisted challenge response physical layer authentication method, applied to a base station, characterized in that: include: Sending a pilot signal to a user terminal through a target channel to achieve channel pre-sharing between the base station and the user terminal; wherein different channel configuration information of the target channel is determined based on a transmit power budget of the base station and a reflection matrix of an intelligent reflecting surface IRS; When the transmit power budget of the base station changes, sending a challenge signal to the user terminal according to the channel configuration information randomly selected from the different channel configuration information; receiving an encrypted response signal sent by the user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; and the target channel configuration information is determined based on the pilot signal; The encrypted response signal is decrypted according to the randomly selected channel configuration information to obtain decrypted information, and identity authentication is performed on the user terminal according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

2. The intelligent reflective surface assisted challenge response physical layer authentication method according to claim 1, characterized in that: The target channel is modeled by the following formula: ； in, and are the channels of Alice-IRS and IRS-Bob respectively, is the reflection matrix of IRS, is the base station power, for noise; is the vector signal sent by the legitimate user Alice, is the signal received at the base station Bob, represents the complex channel coefficient between the base station Bob and the IRS unit; H is the conjugate transpose of the matrix.

3. The intelligent reflective surface assisted challenge response physical layer authentication method according to claim 1, characterized in that: The transmit power budget of the base station is optimized by the following steps: Taking different transmission powers of the base station and the reflection matrix of the IRS as decision variables, constructing an optimization problem with maximizing the communication success rate of the user end and minimizing the success rate of the eavesdropper as the optimization goal; and solving the optimization problem to obtain an optimized transmission power budget; The optimization problem is expressed as follows: ； in, is the transmission power of the base station, is the reflection matrix of IRS, is the communication success rate of the user end, is the communication success rate of the eavesdropper; The constraints of the optimization problem are expressed as follows: ； Among them, || || is the norm operation, is the transmit power budget, n is the number of reflection units.

4. The intelligent reflective surface assisted challenge response physical layer authentication method according to claim 1 or 3, characterized in that: The transmit power budget of the base station is also optimized by the following steps: The transmission power budget is adjusted according to at least one of the real-time communication load and the environmental noise level of the target channel by adopting a power dynamic allocation strategy to obtain an optimized transmission power budget.

5. The intelligent reflective surface assisted challenge response physical layer authentication method according to claim 1, characterized in that: The different channel configuration information of the target channel is also determined based on the transmit power budget of the base station, the reflection matrix of the intelligent reflection surface IRS and the physical layer characteristic parameters; The physical layer characteristic parameter is determined by at least one of received signal strength and signal arrival time difference.

6. An intelligent reflective surface assisted challenge response physical layer authentication method, applied to a user end, characterized in that: include: Receive a pilot signal sent by a base station through a target channel; wherein different channel configuration information of the target channel is determined based on the transmit power budget of the base station and the reflection matrix of the intelligent reflection surface IRS Determine target channel configuration information according to the pilot signal; receiving a challenge signal sent by the base station; Decoding the challenge signal based on the target channel configuration information to obtain decoded information, and encrypting the decoded information according to the channel configuration information randomly selected from the different channel configuration information to generate an encrypted response signal; The encrypted response signal is sent to the base station so that the base station can perform identity authentication on the user terminal.

7. An intelligent reflective surface assisted challenge response physical layer authentication device, characterized in that: include: A first sending module is used to send a pilot signal to a user terminal through a target channel to realize channel pre-sharing between a base station and a user terminal; wherein different channel configuration information of the target channel is determined based on a transmit power budget of the base station and a reflection matrix of an intelligent reflecting surface IRS; A second sending module is used to send a challenge signal to the user terminal according to the channel configuration information randomly selected from the different channel configuration information when the transmission power budget of the base station changes; A first receiving module is configured to receive an encrypted response signal sent by the user terminal; wherein the encrypted response signal is generated based on the user terminal encrypting the decoding information according to the randomly selected channel configuration information, and the decoding information is obtained based on the user terminal decoding according to the target channel configuration information; and the target channel configuration information is determined based on the pilot signal; The decryption and authentication module is used to decrypt the encrypted response signal according to the randomly selected channel configuration information to obtain decrypted information, and to perform identity authentication on the user terminal according to the decrypted information and the randomly selected channel configuration to obtain an authentication result.

8. An intelligent reflective surface assisted challenge response physical layer authentication device, characterized in that: include: The second receiving module is used to receive the pilot signal sent by the base station through the target channel; wherein the different channel configuration information of the target channel is determined based on the transmit power budget of the base station and the reflection matrix of the intelligent reflecting surface IRS A processing module, configured to determine target channel configuration information according to the pilot signal; A third receiving module, used to receive the challenge signal sent by the base station; an encryption module, configured to decode the challenge signal based on the target channel configuration information to obtain decoded information, and encrypt the decoded information according to the channel configuration information randomly selected from the different channel configuration information to generate an encrypted response signal; The third sending module is used to send the encrypted response signal to the base station so that the base station can perform identity authentication on the user terminal.

9. 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 smart reflective surface assisted challenge response physical layer authentication method according to any one of claims 1 to 6 is implemented.

10. 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 smart reflective surface assisted challenge response physical layer authentication method according to any one of claims 1 to 6 is implemented.

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