A high-security double-encryption information communication method based on reconfigurable acoustic holography

Abstract

The application discloses a high-security double-encryption information communication method based on reconfigurable acoustic holography. The correct information image and the pseudo information image are mixed and then input into a dynamic acoustic holographic neural network to output ciphertext information and an electronic key; a reconfigurable acoustic holographic phase plate carrying the ciphertext information is prepared; based on distance position information, partitioned electrically encoded ultrasonic transducers and the reconfigurable acoustic holographic phase plate are placed; an electrically encoded sequence is input into the transducer; the correct information image is decoded and reconstructed and then visualized on a sound field reconstruction visualization plane; and the reconfigurable acoustic holographic phase plate can be restored for the next encryption information communication. The method can mix the correct information into multiple groups of pseudo information to improve information security, and can encode the electronic key in multiple dimensions to further improve information decoding difficulty, and has a read-once-burn-after feature, so that secondary information leakage can be fundamentally prevented; the method is simple in equipment and difficult in information decryption, and is suitable for high-throughput transmission of text information.

Description

Technical Field

[0001] This invention relates to an encrypted information communication method, and to the field of information security transmission technology, specifically to a high-security double-encrypted information communication method based on reconfigurable acoustic holography. Background Technology

[0002] With the increasing demands for information security, how to achieve concealed expression, secure transmission, and rapid recovery of information during transmission has become an important research direction in the field of information transmission. Most existing secure information transmission technologies rely on electromagnetic communication links and digital encryption algorithms. They achieve secure transmission by mathematically transforming, encoding, encapsulating, and protecting the original information with keys. While these schemes have a certain degree of universality, their security is primarily based on differences in algorithm complexity and computational resources. They still suffer from problems such as easy key interception, easy copying of ciphertext, obvious transmission link characteristics, and insufficient anti-interference capabilities in specific complex environments.

[0003] Acoustic technology, due to its excellent adaptability to various media, strong concealment, and unique propagation advantages in underwater, enclosed spaces, and complex media, is increasingly being used to carry and transmit information, especially in underwater applications. In particular, acoustic holography can reconstruct a predetermined spatial sound field distribution in a target area by controlling parameters such as the amplitude, phase, and propagation path of the incident sound field, thus providing the technical basis for mapping information onto the target sound field. However, existing acoustic holography-related technologies mainly focus on applications such as sound field reconstruction, sound manipulation, particle manipulation, energy focusing, or conventional acoustic communication, paying more attention to the accuracy of sound field generation, device design, and reconstruction effects, rather than addressing the construction of encryption mechanisms and rapid decoding issues in secure information transmission scenarios.

[0004] Furthermore, most existing information transmission schemes based on acoustic holography employ static sound field design, resulting in a relatively simple information carrying method. Once the acoustic device carrying the information is acquired, the information is at risk of being reverse-analyzed or copied, making it difficult to establish highly secure physical decryption conditions with multi-parameter coupling. Simultaneously, traditional schemes typically fail to use sound field design variables such as incident sound field wavefront characteristics, propagation distance, phase plate spatial position, and timing control parameters as a decryption key, leading to limited security levels and insufficient resistance to unauthorized cracking. Moreover, existing information recovery methods often rely on complex numerical inversion, back-end image reconstruction, or electronic signal processing, resulting in cumbersome and inefficient decoding steps, hindering simple and intuitive rapid reading. Therefore, it is necessary to propose a new information transmission technology that combines the encrypted carrier with sound field manipulation, and through the coordinated use of multiple physical parameters, ensures that only authorized users can correctly reconstruct the target information, while unauthorized users can only obtain false or invalid information. Summary of the Invention

[0005] To address the problems existing in the background technology, this invention provides a high-security dual-encryption information communication method based on reconfigurable acoustic holography. This invention overcomes the limitations of existing information transmission technologies in achieving high security, high integration, and fast decoding. Addressing the shortcomings of existing sound field design and control methods in information encryption transmission and efficient decoding, such as poor security, low toxicity, and complex equipment, this invention utilizes encodeable dynamic acoustic holography to conceal the information to be transmitted within the target sound field reconstruction process. The incident sound field encoding, phase plate information, and spatial position parameters are collectively constructed as decryption conditions, thereby achieving high-security information transmission and efficient decoding. Furthermore, from the perspective of multi-parameter sound field design and spatial dynamic reconstruction, a complete technical solution is established, from the design of information authenticity and high security to multi-dimensional key physical decoding.

[0006] The technical solution adopted in this invention is: The high-security double-encryption information communication method based on reconfigurable acoustic holography of the present invention includes: Step 1) Mix the correct information image to be transmitted with several pseudo information images to obtain a superimposed image set, and then input it into the dynamic acoustic holographic neural network for processing to output ciphertext information and its electronic key. The electronic key includes the electronic code sequence and distance and position information.

[0007] Step 2) After writing the encrypted information into the initial semi-crystalline polymer plate with a laser, a reconfigurable acoustic holographic phase plate is obtained.

[0008] Step 3) During encrypted information communication, based on distance and position information, the partitioned electrically coded ultrasonic transducer and the reconfigurable acoustic holographic phase plate are placed in front of the sound field reconstruction visualization plane in sequence. The electrically coded sequence is input into the partitioned electrically coded ultrasonic transducer. After the correct information image is decoded and reconstructed, it is visualized on the sound field reconstruction visualization plane. After completion, the reconfigurable acoustic holographic phase plate gradually returns to the initial semi-crystalline polymer plate and continues to carry out the next encrypted information communication, realizing high-security double-encrypted information communication.

[0009] In step 1), the correct information image and each pseudo information image have the same size, and are smaller than or equal to the size of the reconstructible acoustic holographic phase plate.

[0010] In step 1), the dynamic acoustic holographic neural network is specifically a physical information neural network of the sound field forward propagation model.

[0011] In step 1), the dynamic acoustic holographic neural network first converts the superimposed image set into several target sound fields during processing. The superimposed image set and each target sound field are then input into the dynamic acoustic holographic neural network for iterative optimization. First, the physical model parameters are initialized, including the single-layer reconfigurable acoustic holographic phase, the incident sound field, and the distance and depth coordinates of the correct information image and each pseudo-information image in the superimposed image set. Then, the sound field forward propagation process is performed. In each iteration, the dynamic acoustic holographic neural network, based on the physical model parameters obtained in the current iteration, uses the sound field forward propagation model to obtain the single-layer reconfigurable acoustic hologram at different distances from itself where the incident sound field of the current iteration has propagated. After phase, the different reconstructed sound fields generated are decoded on the sound field reconstruction visualization plane. A loss function is established based on each reconstructed sound field and the target sound field in the current round. By minimizing the loss function, the physical model parameters are iteratively optimized using the gradient descent optimization algorithm to obtain the reconstructed sound field that is closest to each target sound field. After the iterative optimization is completed, the single-layer reconstructable acoustic holographic phase, incident sound field and distance position information between the target sound field of the correct information image and the sound field reconstruction visualization plane are determined as key information. The optimized single-layer reconstructable acoustic holographic phase is used as ciphertext information. The optimized incident sound field is transformed to obtain the 0 / 1 amplitude coded modulation electrical coding sequence.

[0012] During the reverse iterative optimization process, the incident sound field distributions of the correct information image and each pseudo information image are inconsistent, but the single-layer reconfigurable acoustic hologram phases corresponding to different information are completely consistent.

[0013] In step 2), the initial semi-crystalline polymer plate is made of a polymer with reversible thermal phase change properties. The encrypted information is hidden in the initial semi-crystalline polymer plate by laser writing and is gradually and automatically restored at room temperature, eliminating the written encrypted information. This has the characteristic of being self-destructing after reading, thus achieving double security encryption.

[0014] In step 3), the partitioned electrically coded ultrasonic transducer, the reconfigurable acoustic holographic phase plate, and the sound field reconstruction visualization plane are arranged in parallel and facing each other in sequence. The distance and position information includes the placement distance between the partitioned electrically coded ultrasonic transducer, the reconfigurable acoustic holographic phase plate, and the sound field reconstruction visualization plane, so that only the correctly reconstructed information image is decoded on the sound field reconstruction visualization plane.

[0015] In step 3), the piezoelectric electrode of the partitioned electrically coded ultrasonic transducer is divided into multiple discrete partitions. Each discrete partition is controlled by a switch circuit in the switch control system to control whether the individual discrete partition is connected to the ultrasonic input signal, thereby realizing dynamic control of the incident sound field distribution.

[0016] In step 3), during encrypted information communication, the reconfigurable acoustic holographic phase plate is physically transmitted to the user as a container carrying ciphertext, and the electronically encoded sequence and distance location information in the electronic key are electronically sent to the user's computer or mobile phone so as to be decoded and reconstructed on the sound field reconstruction visualization plane.

[0017] In step 3), the reconfigurable acoustic holographic phase plate, when decoding and reconstruction are performed based on an incorrect electrical coding sequence, cannot visualize the correct information image; when decoding and reconstruction are performed based on a correct electrical coding sequence, and the reconfigurable acoustic holographic phase plate is moved between the partitioned electrical coding ultrasonic transducer and the sound field reconstruction visualization plane, the correct information image and the pseudo information images in the superimposed image set cannot be deciphered.

[0018] The dynamic acoustic holographic device for encrypted acoustic communication in this invention consists of a single-layer reconfigurable acoustic holographic phase plate and a partitioned electrically coded ultrasonic transducer. The single-layer acoustic holographic phase plate is made of a phototransformable polymer, and each element of the partitioned electrically coded ultrasonic transducer has electrically controllable coding characteristics. When transmitting encrypted information based on the dynamic acoustic holographic device, the information to be transmitted is first embedded into multiple "pseudo-information" to jointly encode a ciphertext and an electronic key, which are respectively the binary phase distribution, the distance and position information of the reconfigurable acoustic holographic phase plate, and the electrically coded sequence of the partitioned electrically coded ultrasonic transducer. Then, only by correctly controlling the input electronic coding sequence of the partitioned electronically coded ultrasonic transducer and the distance between the reconfigurable acoustic holographic phase plate and the partitioned electronically coded ultrasonic transducer according to the electronic key can the correct sound field distribution be reconstructed on the imaging surface using the dynamic acoustic holography system, and the encrypted information be decoded using the sound field visualization method. More importantly, since the single-layer reconfigurable acoustic holographic phase plate is made of reversible crystalline polymer, the acoustic ciphertext information written on the single-layer reconfigurable acoustic holographic phase plate will disappear after a set time, thus achieving "read and burn".

[0019] This invention is a high-security acoustic encryption transmission and fast decoding method based on encodeable dynamic acoustic holography. Unlike traditional encryption schemes based on the physical or information layer, this invention aims to provide an acoustic solution for secure information transmission. It utilizes the multi-parameter adjustable characteristics of the sound field to covertly embed the information to be transmitted into the dynamic acoustic holographic reconstruction process, thereby achieving high-security transmission and efficient decoding. It is known that arbitrarily complex sound field distributions can be reconstructed in space by adjusting the amplitude and phase of the incident sound field, and amplitude, phase distribution, and distance information can all be used as parameters in sound field design. Therefore, encrypted information can be carried through the sound field, and the sound field parameters (amplitude, phase, distance, etc.) can be used as decryption keys to decode the encrypted information. Specifically, this invention uses a dynamic holographic sound field to simultaneously encrypt and decode the target transmitted information. In implementation, the information to be transmitted corresponds to the target sound field to be reconstructed. During encryption, the encrypted information and multiple pseudo-information are first input into the sound field design algorithm, outputting a ciphertext and a set of keys. The spatial two-dimensional phase distribution, as the ciphertext, is encoded into the acoustic holographic phase plate via laser writing and directly distributed to the user. The incident sound field wavefront coding distribution and phase plate position information are sent to the user electronically as the keys. During decryption, the user must simultaneously follow the key requirements, encode and adjust the incident sound field information, and place the acoustic holographic phase plate in the correct position to reconstruct the correct sound field on the target plane. The encrypted information can then be directly decoded through liquid surface visualization or acoustic-thermal visualization. Simultaneously, the acoustic holographic phase plate automatically destroys the ciphertext after a specified time. In summary, based on the above multi-sound field collaborative design and dynamically programmable acoustic holography technology, encrypted information can be transmitted simply and efficiently, achieving high-security transmission and efficient decoding, which is of great significance to underwater information transmission and information security.

[0020] The beneficial effects of this invention are: 1) This invention achieves secure encrypted transmission and rapid information decoding based on dynamic acoustic holography technology. It decomposes encrypted information into ciphertext containing the correct encrypted information and two security keys. Secure transmission of encrypted information is achieved through physical encryption by a reconfigurable acoustic holographic phase plate and electronic transmission of multi-dimensional keys, respectively. It also achieves rapid visual decoding based on holographic ultrasound.

[0021] 2) This invention achieves secure encrypted transmission and rapid information decoding based on dynamic acoustic holography technology. It features a compact structure, high operability, and high reliability. The entire acoustic holographic system only requires a parallel arrangement of a partitioned electrically coded ultrasonic transducer and a reconfigurable acoustic holographic phase plate to achieve secure transmission and rapid reconstruction of a holographic sound field containing correctly encrypted information under a single ultrasonic signal input.

[0022] In summary, the method of this invention can improve information security by mixing correct information into multiple sets of false information, and simultaneously encode the electronic key into multiple dimensions to further increase the difficulty of information decoding. It also has the characteristic of self-destruction after reading, which can fundamentally prevent secondary leakage of information. The method and equipment are simple, the information is difficult to decipher, and it is suitable for high-throughput transmission of text information. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the method of the present invention; Figure 2 This is a high-security information transmission graph based on the hiding of multiple pseudo-information methods in the present invention; Figure 3 This is a schematic diagram of the self-destructing characteristics of a reconfigurable acoustic holographic phase plate based on a reversible thermal phase change crystalline polymer, according to the method of the present invention. Figure 4 This is a schematic diagram of the information encryption and decryption process for high-security encrypted information transmission according to the method of the present invention; Figure 5 This is a schematic diagram of the encrypted information transmission process of the method of the present invention; Figure 6 This is a schematic diagram of the target transmission information and the encrypted output ciphertext and key in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram illustrating the correct decoding of information and the reproduction of false information in Embodiment 1 of the present invention; Figure 8 This is a schematic diagram of the ciphertext and key of the correctly decoded encrypted information transmission according to Embodiment 2 of the present invention; Figure 9 This is a schematic diagram of encrypted information transmission and information decoding in Embodiment 2 of the present invention; In the figure: 1. Correct information image, 2. False information image, 3. Overlay image set, 4. Ciphertext information, 5. Electronic key, 6. Switch control system, 7. Partitioned electronically coded ultrasonic transducer, 8. Reconfigurable acoustic holographic phase plate, 9. Sound field reconstruction visualization plane, 10. Initial semi-crystalline polymer plate. Detailed Implementation

[0024] To enable those skilled in the art to better understand and implement the technical solutions of this invention, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0025] In the description of this invention, it should be understood that the terms "middle," "upper," "lower," "left," "right," "lateral," "longitudinal," "horizontal," "vertical," "axial," "mirror image," "length," "width," and "thickness," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the technical solutions of this invention and simplifying the description, and do not indicate or imply that the device or equipment referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. In the description of this invention, unless otherwise stated, "a plurality of" means two or more, and will not be elaborated further here.

[0026] like Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, the high-security double-encryption information communication method based on reconfigurable acoustic holography of the present invention is as follows: The correct information image 1 to be transmitted and several pseudo information images 2 are mixed to obtain a superimposed image set 3, such as a correct information image 1 containing the correct information ZJU and two pseudo information images 2 containing the incorrect information SME and 1897 respectively. This image set is then input into a dynamic acoustic holographic neural network for processing. Specifically, the dynamic acoustic holographic neural network is a physical information neural network PINN (Physics-Informed Neural Networks) for the forward propagation model of the sound field. The dynamic acoustic holographic neural network does not require pre-training and can directly iteratively optimize the acoustic holographic phase distribution as physical ciphertext information and the incident sound field amplitude encoding and depth coordinate information parameters corresponding to the correct information.

[0027] In the physical information neural network processing, the superimposed image set 3 is first converted into several target sound fields, i.e., the sound energy distribution maps of the correct information image 1 and each pseudo-information image 2 are obtained. These are then constructed as target sound fields. The superimposed image set 3 and its target sound fields are input into the dynamic acoustic holographic neural network for iterative optimization. First, the physical model parameters are initialized, including the single-layer reconstructable acoustic holographic phase, the incident sound field, and the distance and depth coordinate parameters of the correct information image 1 and each pseudo-information image 2 in the superimposed image set 3. The incident sound field is a sound field modulated by 8×8 0 / 1 amplitude codes. Furthermore, ultrasound undergoes scattering and diffraction during propagation; therefore, the reconstructed sound field differs depending on the propagation distance. The distance and depth coordinate parameters... The key primarily determines the distance between the single-layer reconfigurable acoustic holographic phase and the incident sound field, as well as the distance between the target reconstructed sound field plane and the single-layer reconfigurable acoustic holographic phase, and is ultimately transmitted to the user as the key. Then, the sound field forward propagation process is performed. In each iteration of the dynamic acoustic holographic neural network, based on the physical model parameters obtained in the current iteration, the incident sound field in the current iteration is obtained through the sound field forward propagation model after propagating past the single-layer reconfigurable acoustic holographic phase at different distances. Different reconstructed sound fields are then decoded and generated on the sound field reconstruction visualization plane 9. A loss function is established based on each reconstructed sound field and the target sound field in the current iteration. By minimizing the loss function, the physical model parameters are iteratively optimized using the gradient descent optimization algorithm to obtain... During the reverse iterative optimization process, the incident sound field distributions of the correct information image 1 and each pseudo-information image 2 are inconsistent, but the single-layer reconstructable acoustic holographic phases corresponding to different information are completely consistent. After the iterative optimization is completed, the single-layer reconstructable acoustic holographic phase, incident sound field, and distance position information between the target sound field of the correct information image 1 and the sound field reconstruction visualization plane 9 are determined as key information. The optimized single-layer reconstructable acoustic holographic phase is output as the ciphertext information 4 of the two-dimensional acoustic holographic distribution. The single-layer reconstructable acoustic holographic phase contains not only the correct information but also pseudo-information used for interference decoding. The pseudo-information also has its corresponding incident sound field coding distribution and single-layer acoustic holographic phase. The position information corresponding to the holographic phase plate is not sent to the user as a key. Only by using the correct electronic key 5 for decoding can the correct information be reconstructed. Otherwise, false information will be reconstructed to confuse the correct information, thereby increasing the security of the information. After the optimized incident sound field is transformed, a 0 / 1 amplitude-coded modulation electronic code sequence is obtained. That is, after ultra-sparse discretization and binarization operations, it is transformed into an 8×8 amplitude array distribution and forms the corresponding 0 / 1 electronic code sequence. The electronic code sequence (key 1) and the distance position information D (key 2) constitute electronic key 5. The encrypted information is transmitted through sound field reconstruction. The sound field is visualized through water surface ripples or a thermal sheet, thereby realizing the visualization of the transmitted encrypted information.

[0028] In encrypted information communication, the ciphertext information 4 is written into the initial semi-crystalline polymer plate 10 via laser scanning to obtain a reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4. The correct information image 1 and each pseudo information image 2 have the same size, and are smaller than or equal to the plate size of the reconfigurable acoustic holographic phase plate 8. Then, the reconfigurable acoustic holographic phase plate 8 is physically transmitted directly to the user as a container carrying the ciphertext, and the electronically encoded sequence and distance position information in the electronic key 5 are electronically sent to the user's computer or mobile phone for decoding and reconstruction on the sound field reconstruction visualization plane 9.

[0029] The initial semi-crystalline polymer plate 10 used in this invention is made of a polymer with reversible thermal phase change properties. This polymer exhibits both semi-crystalline and molten states at different temperatures, with a significant difference in sound velocity between the crystalline and molten states. Therefore, it can be used to control the wavefront of transmitted sound waves. Through thermal encoding, the thermal phase change material can be made to have locally patterned sound velocity differences, thus serving as a reconfigurable acoustic holographic phase plate 8 to achieve phase encoding control of the incident sound field. Specifically, polycaprolactone material can be used, with a smooth surface. By doping the material with a photothermal conversion medium, locally patterned molten regions can be written onto the crystalline polymer material using laser technology, thereby achieving phase spatial encoding of the transmitted sound field. Figure 3 As shown, this is the information writing and self-erasing process of the initial semi-crystalline polymer plate 10 with self-destructing read-after-read characteristics. The encrypted information 4 is hidden in the initial semi-crystalline polymer plate 10 by laser writing and gradually recovers automatically at room temperature. The molten area in the single-layer reconfigurable acoustic holographic phase plate 8 will gradually recover to its initial crystalline state, thereby erasing the written encrypted information 4. That is, it has the self-destructing read-after-read characteristics, preventing secondary leakage of information and realizing physical-electronic dual encryption of information.

[0030] Then, based on distance and position information, the user places the partitioned electrically coded ultrasonic transducer 7 and the reconfigurable acoustic holographic phase plate 8 coaxially in front of the sound field reconstruction visualization plane 9. The sound field reconstruction visualization plane 9 can be a liquid surface / interface or a thermosensitive colorimetric material, which can be based on the acoustic-induced liquid surface deformation effect or the acoustic-thermal effect to visualize the sound field of the target plane. The partitioned electrically coded ultrasonic transducer 7, the reconfigurable acoustic holographic phase plate 8, and the sound field reconstruction visualization plane 9 are arranged in parallel facing each other to form a dynamic acoustic holographic system. The piezoelectric electrodes of the partitioned electrically coded ultrasonic transducer 7 are divided into multiple discrete partitions by a dicing machine. Each discrete partition is controlled by a switch circuit in the switch control system 6 to control whether the individual discrete partition is connected to the ultrasonic input signal, thereby realizing dynamic spatial phase control of the incident sound field distribution. The partitioned electrically coded ultrasonic transducer 7 is the same as that in patent CN120281402B. The switch control system 6 adopts a field-programmable gate array (FPGA). The electrical coding sequence is input into the partitioned electrical coding ultrasonic transducer 7. The state of each array element of the partitioned electrical coding ultrasonic transducer 7 is set to "on / off" according to the electrical coding sequence through the switch control circuit to realize the amplitude modulation of the incident sound wave. Then, after the incident sound wave is transmitted to the single-layer reconfigurable acoustic holographic phase plate 8, the encrypted information 4 on the single-layer reconfigurable acoustic holographic phase plate 8 will be coupled into the incident sound field. After the correct information image 1 is decoded and reconstructed, it is visualized on the sound field reconstruction visualization plane 9. The reconstructed sound field will be visualized through the acoustic-thermal effect or acoustic-induced liquid surface deformation, and the encrypted information 4 in the single-layer reconfigurable acoustic holographic phase plate 8 will be directly decoded and displayed, realizing the fast and efficient decoding of encrypted information.

[0031] After the aforementioned target information transmission is completed, upon reaching the recovery time point of the reversible phase change crystalline polymer material, the single-layer reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4 will be restored to the initial semi-crystalline polymer plate 10 in its initial crystalline state before laser absorption, and no more information will be written. At this point, even if the correct electronic key 5 is used for decoding, the correct ciphertext information 4 cannot be reproduced, effectively preventing secondary leakage of information. The restored initial semi-crystalline polymer plate 10 can continue to carry out the next encrypted information communication, realizing highly secure double-encrypted information communication.

[0032] With the reconfigurable acoustic holographic phase plate 8, when decoding and reconstruction are performed based on an incorrect electrical coding sequence, the correct information image 1 cannot be visualized. When decoding and reconstruction are performed based on the correct electrical coding sequence, and the reconfigurable acoustic holographic phase plate 8 is moved between the partitioned electrical coding ultrasonic transducer 7 and the sound field reconstruction visualization plane 9, the correct information image 1 and the pseudo-information images 2 in the superimposed image set 3 cannot be deciphered. Only when the partitioned electrical coding ultrasonic transducer 7 controls and modulates the incident sound field according to the correct electrical coding sequence, and the reconfigurable acoustic holographic phase plate 8 is placed at the correct distance to perform phase modulation on the incident sound field, can the correct encrypted information be decoded on the sound field reconstruction visualization plane 9. After the user completes the decoding of the correct information based on the correct electrical coding sequence and the correct distance and position information, the reconfigurable acoustic holographic phase plate 8 carrying the encrypted information will undergo material self-recovery after a predetermined time, thereby achieving the effect of "read and burn".

[0033] This invention offers high security during information transmission. Even if a hacker obtains the reconfigurable acoustic holographic phase plate 8 containing encrypted information, they will be unable to correctly transmit the encrypted information if they cannot crack the electrical coding sequence and distance position information of the partitioned electrically coded ultrasonic transducer 7. The electrical coding sequence consists of N 0 / 1 codes. For example, if the partitioned electrically coded ultrasonic transducer 7 is divided into n×m independent electrode partitions by physical means such as a dicing machine or laser cutting, the electrical coding sequence will then consist of n×m 0 / 1 sequences. The distance position information consists of two depth information components: the depth of the reconfigurable acoustic holographic phase plate 8 from the partitioned electrically coded ultrasonic transducer 7 and the sound field reconstruction visualization plane 9. Figure 2 As shown, even if a hacker obtains the single-layer reconfigurable acoustic holographic phase plate 8 containing the encrypted information 4, without a completely correct electronic key, due to the interference of false information caused by incorrect decoding, even if the hacker tries to traverse the partitioned electronically encoded ultrasonic transducer 7 and the distance position information, only the correct information and false information will be reproduced at the same time, and the correct information still cannot be deciphered.

[0034] If a hacker only intercepts the electronic key 5, and without the reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4, they will be unable to crack the transmitted encrypted information through traversal or codebook lookup, demonstrating the high security of the physical-information dual encryption method. Even if a hacker builds a dynamic holographic system with a partitioned electrically coded ultrasonic transducer 7 and a reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4, and the ciphertext information 4 is also intercepted, without obtaining the correct electronic key 5, it will be almost impossible to decode the correct information. The specific situation is as follows: Scenario 1: Assuming the hacker has not obtained the electronic key 5, if all elements of the partitioned electronically encoded ultrasonic transducer 7 are activated simultaneously, a planar sound wave will be directly excited and generated, illuminating the reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4 to decipher the ciphertext information. At this time, a chaotic sound field distribution without any information will be generated in space, containing no useful information. If the reconfigurable acoustic holographic phase plate 8 is moved to try to decode the correct distance and position information, only a false message will be decoded to cover up the real encrypted information.

[0035] Scenario 2: Suppose the hacker obtains the correct distance and location information, and places the reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4 in parallel in front of the partitioned electronically encoded ultrasonic transducer 7 to decode the ciphertext information. If the electronically encoded sequence of the partitioned electronically encoded ultrasonic transducer 7 is traversed and queried at this time, the spatial sound field distribution of the false information and the real information will be reproduced in space at the same time, and the real encrypted information cannot be accurately obtained.

[0036] Scenario 3: Suppose the hacker obtains a partial correct electronic code sequence. During the experiment, the control partition electronic code ultrasonic transducer 7 generates an incorrect incident sound field and illuminates the reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4 to crack the ciphertext information. At this time, a sound field distribution containing both correct and false information will be generated in space, causing waveform distribution disorder and interfering with the reading of correct information.

[0037] Scenario 4: Assuming the hacker obtains the correct electronically encoded sequence, during the experiment, the controlled partition electronically encoded ultrasonic transducer 7 generates the correct incident sound field and illuminates the reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4 to decipher the ciphertext information. However, if the correct distance and position information is not obtained, the information can only be decoded by scanning and moving the position. But since multiple false information is embedded under the other distance and position parameters, the set of false information and real information will be obtained during the scanning process, confusing the correct information.

[0038] Therefore, to simultaneously identify the aforementioned false information, it is necessary to effectively embed the correct encrypted information into the sound field design process. Based on this, the design method is as follows: First, the sound field distribution A corresponding to the correctly encrypted information, along with N sound field distributions B... i The sound fields i=1,2,…,N are collectively input into the dynamic acoustic holographic neural network as the target design sound fields. Among them, the N+1 sound fields have their own electrical coding sequences S. i i=1,2,…,N+1 and distance / location information L i , i=1,2,…,N+1.

[0039] The standards for designing pseudo-information are as follows: A pseudo-sound field distribution B´1 is selected as the reconstructed sound field when all elements of the partitioned electronically coded ultrasonic transducer 7 are fully open, that is, its electronically coded sequence is '111…111'.

[0040] Select a pseudo sound field distribution B´2 whose distance and position information is completely consistent with the correct encrypted information sound field distribution A, but the array elements of the partitioned electronically coded ultrasonic transducer 7 corresponding to the pseudo sound field distribution B´2 are all open, that is, its electronically coded sequence is '111…111'.

[0041] Select M pseudo-sound field distributions B' i The electronically encoded sequences of the ultrasonic transducer 7, i=3,…,N, and the correctly encrypted sound field distribution A, are completely identical, but the pseudo sound field distribution B' is completely different. i The distance and location information and the sound field distribution A of the correctly encrypted information are completely inconsistent.

[0042] Based on the above optimization constraints, consider a single correct information sound field distribution A and N information sound field distributions B'. i The global collaborative optimization design is performed for i=1,2,…,N, and the final output is the binary phase distribution information containing all acoustic information as ciphertext information 4, and the electronic code sequence and distance position information corresponding to the correct encrypted information sound field distribution A as electronic key 5.

[0043] Then, the encrypted information 4 of the binary phase distribution is written into the initial semi-crystalline polymer plate 10 by laser, and a reconfigurable acoustic holographic phase plate 8 is prepared and given to the user by physical means.

[0044] Furthermore, since the initial semi-crystalline polymer plate 10 has reversible material properties, it can realize the self-recovery of material properties under temperature changes, realize the read-and-burn of the encrypted information 4, and prevent secondary leakage of transmitted information.

[0045] This invention enables rapid decoding during information transmission. Due to the mechanical properties and acoustic-thermal effects of sound waves, efficient decoding and direct display of acoustic information can be achieved using water surface ripple visualization and acoustic-thermal display methods. For example, by placing the dynamic acoustic holographic system at a depth of L2 below the liquid surface according to the correct distance and position information, a ripple pattern consistent with the preset sound field distribution will be displayed on the liquid surface. A thermal color display screen can be arranged at a position plane L2 away from the reconfigurable acoustic holographic phase plate 8, and the color change pattern consistent with the preset sound field distribution can be displayed on the screen using the acoustic field thermal effect.

[0046] Specific embodiments of the present invention are as follows: Example 1:

[0047] The high-security encrypted transmission of the "ZJU" text information based on dynamic acoustic holography includes the following steps: Step S1: As Figure 6 As shown, the encrypted information "ZJU" and the two pseudo-information messages "SME" and "1897" are first mixed together as the target optimized sound field and input into the dynamic acoustic holographic neural network for design. At this point, the positional distance information of "ZJU" is preset to D1 = 20 mm and D2 = 10 mm. With D1 = 10 mm and D2 = 10 mm, and the incident sound field being in the case of the partitioned electrically coded ultrasonic transducer 7 with all elements fully open, the pseudo-information "1897" will be reconstructed on the sound field reconstruction visualization plane 9. Simultaneously, with the positional information set to D1 = 20 mm and D2 = 10 mm, another pseudo-information message "SME" is used to interfere with the determination of the correct information. Based on the above preset conditions, the neural network is used to simultaneously design a single correct encrypted information "ZJU" and two pseudo-information messages "SME" and "1897". Through repeated forward propagation and reverse optimization processes, all the correct and pseudo-information messages can be jointly encoded into the encrypted information 4. Through multiple iterations and optimizations, the final output will be a binary phase distribution 3φ and the key corresponding to the correct encryption information "ZJU": position distance information and the "on / off" control status of the 8×8 array elements of the partitioned electrically coded ultrasonic transducer 7.

[0048] S2: The aforementioned binary phase distribution 3φ is written into a reversible phase change crystalline polymer material using laser writing to prepare a single-layer reconfigurable acoustic holographic phase plate 8, which serves as the physical container for the encrypted information 4 and is sent to the user. Simultaneously, the location distance information corresponding to the "ZJU" encrypted information and the electronically encoded sequence '11100001110001001010001001001000001111010001111011101110111000010110' of each electrode unit of the partitioned electronically encoded ultrasonic transducer 7 are transmitted electronically to the receiving user as the electronic key 5 for information decoding.

[0049] S3: Based on the received ciphertext information 4 and electronic key 5, the user first places the single-layer reconfigurable acoustic holographic phase plate 8 at the corresponding position coaxial with the partitioned electrically coded ultrasonic transducer 7 according to the position distance information D1 = 20 mm and D2 = 10 mm in the electronic key 5. Then, the state of the 8×8 array elements on the partitioned electrically coded ultrasonic transducer 7 is controlled according to the electronic coding sequence '1110000111000100101000100100100000111101000111101110111000010110' in the electronic key 5. This controls the amplitude distribution of the incident sound field and propagates it through the single-layer reconfigurable acoustic holographic phase plate 8 with the ciphertext information 4 written on it, performing wavefront phase modulation. As the modulated sound wave continues to propagate forward, it will eventually reconstruct the target holographic sound field on the sound field reconstruction visualization plane 9.

[0050] S4: Next, as Figure 7 As shown, the sound field reconstruction visualization plane 9 is used for visualization and decryption of encrypted information. On one hand, the sound field reconstruction visualization plane 9 can be set as a liquid surface. Based on acoustic deformation of the liquid surface, the encrypted information can be visualized and decrypted using the water ripples, displaying a "ZJU" ripple shape. On the other hand, through acoustic-thermal effects, a thermochromic film can be placed on the sound field reconstruction visualization plane 9. The encrypted information can be decrypted using the color pattern on the film, at which point the "ZJU" color-changing pattern will be displayed on the film. Simultaneously, without the correct key, the ciphertext information 4 on the single-layer reconfigurable acoustic holographic phase plate 8 cannot be correctly decrypted, and only false information can be obtained through traversal, thus improving the security of correct information decryption.

[0051] S5: Finally, after the above information is decoded, the single-layer reconfigurable acoustic holographic phase plate 8, which has been programmed with ciphertext information 4 by laser, will return to its initial crystallization state under normal temperature conditions, proving that the ciphertext information 4 it carries has been eliminated, realizing the read-and-burn of encrypted information and preventing secondary leakage of information.

[0052] Example 2:

[0053] Using "digital tube" graphics for high-throughput encrypted transmission and efficient real-time decoding of text information.

[0054] S1: As Figure 8As shown, the pattern is used as the target to reconstruct the sound field, and the 14 components on the digital tube are controlled by the electrical coding of different partitioned electrically coded ultrasonic transducers 7. During the design, the above 14 components are input into a dynamic holographic neural network to design the electrical coding sequence of the partitioned electrically coded ultrasonic transducers 7 corresponding to the 14 components. Simultaneously, the above 14 components together constitute the encrypted information 4 to be sent, and the output binary phase distribution is sent to the user as encrypted information 4. At the same time, to transmit information faster, the positional distance information of these 14 components is fixed at D1 = 20 mm and D2 = 10 mm, while the electrical coding sequence of the partitioned electrically coded ultrasonic transducers 7 corresponding to the transmitted text information is still sent to the user as the electronic key 5 of the encrypted information 4, serving as the information decoding key. However, the positional distance information of the other electronic key 5 remains D1 = 20 mm and D2 = 10 mm.

[0055] S2: Next, the aforementioned binary phase distribution is phase-encoded on a reversible phase-change crystalline polymer material using laser writing, forming a single-layer reconfigurable acoustic holographic phase plate 8 carrying ciphertext information 4, which is then sent to the user in a physical container. Simultaneously, the electronic key 5 (including location distance information and the electronically encoded sequence corresponding to each character of the text information) is sent to the user electronically.

[0056] S3: As Figure 9 As shown, based on the obtained electronic key 5, the user first places the single-layer reconfigurable acoustic holographic phase plate 8 carrying the encrypted information 4 at a designated position in front of the partitioned electrically coded ultrasonic transducer 7 according to the position and distance information in the electronic key 5, and keeps the position unchanged; then, based on the electrical coding sequence in the electronic key 5, the user uses the switch control system 6 to adjust the "on / off" state of each array element of the partitioned electrically coded ultrasonic transducer 7 according to the sequence. The incident sound field distribution excited by the partitioned electrically coded ultrasonic transducer 7, after the incident sound field illuminates the single-layer reconfigurable acoustic holographic phase plate 8 with the encrypted information 4 written on it, the phase-modulated transmitted sound wave will dynamically reconstruct different sound field distributions on the sound field reconstruction visualization plane 9 according to the transmission sequence.

[0057] S4: Next, the reconstructed sound field distribution on the sound field reconstruction visualization plane 9 is visualized to decode and read the encrypted information. On one hand, the sound field reconstruction visualization plane 9 can be set exactly at the liquid surface position. Based on the acoustic deformation of the liquid surface plate, a water ripple shape consistent with the sound field distribution will be constructed on the liquid surface, and the sent encrypted text information: HELLOZJU1897 can be read sequentially. On the other hand, a thermochromic film can also be set at the position of the sound field reconstruction visualization plane 9. Then, the sound field will draw a color-changing pattern consistent with the sound wave distribution on the film, and the sent encrypted text information: HELLOZJU1897 can also be read sequentially.

[0058] S5: After the above information is encrypted and transmitted, the single-layer reconfigurable acoustic holographic phase plate 8 carrying the ciphertext information 4 will be restored to its initial crystalline state at room temperature, erasing the binary phase distribution ciphertext information 4 written by laser, realizing the "read and burn function" and preventing secondary leakage of information.

[0059] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0060] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A highly secure double-encrypted information communication method based on reconfigurable acoustic holography, characterized in that, include: Step 1) Mix the correct information image (1) to be transmitted and several pseudo information images (2) to obtain a superimposed image set (3), and then input it into the dynamic acoustic holographic neural network to process and output ciphertext information (4) and its electronic key (5). The electronic key (5) includes the electronic coding sequence and distance position information. Step 2) After writing the encrypted information (4) into the initial semi-crystalline polymer plate (10) by laser, a reconfigurable acoustic holographic phase plate (8) is obtained. Step 3) During encrypted information communication, based on the distance and position information, the partitioned electronically coded ultrasonic transducer (7) and the reconfigurable acoustic holographic phase plate (8) are placed in front of the sound field reconstruction visualization plane (9) in sequence. The electronically coded sequence is input into the partitioned electronically coded ultrasonic transducer (7). The correct information image (1) is decoded and reconstructed and visualized on the sound field reconstruction visualization plane (9). After completion, the reconfigurable acoustic holographic phase plate (8) gradually returns to the initial semi-crystalline polymer plate (10) and continues to carry out the next encrypted information communication, realizing high-security double-encrypted information communication. In step 1), the dynamic acoustic holographic neural network is specifically a physical information neural network of the sound field forward propagation model; In step 1), the dynamic acoustic holographic neural network first converts the superimposed image set (3) into several target sound fields during processing. The superimposed image set (3) and its target sound fields are then input into the dynamic acoustic holographic neural network for iterative optimization. First, the physical model parameters are initialized, including the single-layer reconfigurable acoustic holographic phase, the incident sound field, and the distance and depth coordinates of the superimposed image set (3). Then, the sound field propagation process is performed. In each iteration, the dynamic acoustic holographic neural network, based on the physical model parameters obtained in the current iteration, obtains the incident sound field of the current iteration after propagating through the single-layer reconfigurable acoustic holographic phase at different distances from itself via the sound field propagation model. On the sound field reconstruction visualization plane (9), decode the different reconstructed sound fields generated by reconstruction. Based on the reconstructed sound fields and target sound fields of the current round, establish a loss function. By minimizing the loss function, iteratively optimize the physical model parameters to obtain the reconstructed sound field that is closest to each target sound field. After the iterative optimization is completed, determine the single-layer reconstructable acoustic holographic phase, incident sound field and distance position information between the target sound field of the correct information image (1) and the sound field reconstruction visualization plane (9) as key information. Use the optimized single-layer reconstructable acoustic holographic phase as ciphertext information (4). After the optimized incident sound field is transformed, obtain the 0 / 1 amplitude coding modulation electrical coding sequence.

2. The high-security double-encryption information communication method based on reconfigurable acoustic holography according to claim 1, characterized in that: In step 1), the correct information image (1) and each pseudo information image (2) have the same size and are smaller than or equal to the size of the reconfigurable acoustic holographic phase plate (8).

3. The high-security double-encryption information communication method based on reconfigurable acoustic holography according to claim 1, characterized in that: During the reverse iterative optimization process, the incident sound field distributions of the correct information image (1) and each pseudo information image (2) are inconsistent.

4. The high-security double-encryption information communication method based on reconfigurable acoustic holography according to claim 1, characterized in that: In step 2), the initial semi-crystalline polymer plate (10) is made of a polymer with reversible thermal phase change characteristics. The encrypted information (4) is hidden in the initial semi-crystalline polymer plate (10) by laser writing and is gradually and automatically restored at room temperature, eliminating the written encrypted information (4).

5. The high-security double-encryption information communication method based on reconfigurable acoustic holography according to claim 1, characterized in that: In step 3), the partitioned electrically coded ultrasonic transducer (7), the reconfigurable acoustic holographic phase plate (8), and the sound field reconstruction visualization plane (9) are arranged in parallel facing each other in sequence. The distance position information includes the placement distance between the partitioned electrically coded ultrasonic transducer (7), the reconfigurable acoustic holographic phase plate (8), and the sound field reconstruction visualization plane (9), so that only the correctly reconstructed information image (1) is decoded on the sound field reconstruction visualization plane (9).

6. The high-security double-encryption information communication method based on reconfigurable acoustic holography according to claim 1, characterized in that: In step 3), the piezoelectric electrode of the partitioned coded ultrasonic transducer (7) is divided into multiple discrete partitions. Each discrete partition is controlled by a switch circuit in the switch control system (6) to control whether the individual discrete partition is connected to the ultrasonic input signal, thereby realizing the dynamic control of the incident sound field distribution.

7. The high-security double-encryption information communication method based on reconfigurable acoustic holography according to claim 1, characterized in that: In step 3), during encrypted information communication, the reconfigurable acoustic holographic phase plate (8) is directly transmitted to the user, and the electronic encoding sequence and distance position information in the electronic key (5) are sent to the user electronically so as to perform decoding and reconstruction on the sound field reconstruction visualization plane (9).

8. The high-security double-encryption information communication method based on reconfigurable acoustic holography according to claim 1, characterized in that: In step 3), when the reconfigurable acoustic holographic phase plate (8) is used to decode and reconstruct based on an incorrect electrical coding sequence, the correct information image (1) cannot be visualized. When the correct electrical coding sequence is used to decode and reconstruct, the reconfigurable acoustic holographic phase plate (8) is moved between the partitioned electrical coding ultrasonic transducer (7) and the sound field reconstruction visualization plane (9), and the correct information image (1) and each pseudo information image (2) in the superimposed image set (3) cannot be deciphered.

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