223 results about "Covert communication" patented technology

The invention provides a covert communication method based on near-field broadband super-large-scale array beam splitting. Comprising the following steps: S1, according to an applied near-field covert communication scene, constructing a corresponding communication model by using a beam splitting effect in a broadband XL-MIMO system, carrying out beam training, and describing a received signal expression of the communication model; s2, constructing a signal detection model of a listener according to a near-field covert communication scene, and describing a detection error probability expression and a covert constraint expression; and step S3, the hidden transmission rate is maximized by optimizing the transmitting power and the subcarrier number of the transmitter. According to the method, the two-dimensional optimization problem related to the transmitting power and the subcarriers is converted into the one-dimensional optimization problem related to the discrete variable quantum carrier number, and the concealment rate of a legal receiver is maximized.

The invention discloses an encrypted communication system and method based on cognitive multi-carrier spread spectrum, and belongs to the field of covert communication. The encryption communication system comprises a transmitting device and a receiving device. The transmitting device comprises a data encryption module, a constellation encryption modulation module, a multi-carrier spread spectrum module, a frequency hopping module and a cognitive power distribution module. The receiving device comprises a band-pass filtering module, a de-hopping frequency module, a de-spreading module, a constellation decryption demodulation module, a data decryption module and a coherent combination module. The data encryption module is divided into an interleaving coding unit and a double-rule reversible cellular automaton encryption unit. The cognitive power distribution module continuously scans a wireless electromagnetic environment and carries out real-time spectrum analysis to give power spectrum density results sensed under all frequency hopping frequency sets. According to the invention, continuous detection and dynamic response to the spatial frequency spectrum state can be realized, and the communication concealment, the anti-interference performance and the resource utilization efficiency in a complex electromagnetic environment are remarkably improved by utilizing the frequency spectrum hole.

The invention relates to the technical field of NTN, and discloses a 5G NTN-based multi-mode steganography communication method and a satellite ground communication system, and the method comprises the steps: a ground transmitting terminal selects at least one of voice steganography, text steganography or protocol layer steganography, and generates a multi-mode steganography data stream; performing high-orbit channel optimization processing on the multi-modal steganography data stream, packaging the optimized multi-modal steganography data stream to a physical layer frame adaptive to the 5G NTN standard, and injecting an ephemeris prediction label; the GEO relay satellite forwards the data to a ground receiving end; and the ground receiving end receives and de-encapsulates the multi-mode steganography data stream to obtain the multi-mode steganography data stream, and extracts steganography data from the multi-mode steganography data stream according to an extraction rule corresponding to the steganography mode. According to the embodiment of the invention, through a multi-mode steganography mode, in combination with 5GNTN physical layer frame packaging, the compatibility of an NTN protocol is improved, the steganography data is prevented from being analyzed into abnormal signals by a protocol stack and discarded, and the reliability of covert communication is improved.

The invention discloses a covert communication optimization method based on deep reinforcement learning under limited character input, and belongs to the technical field of wireless communication. According to the method, an optimization problem which takes the minimum average bit error rate as a target function and takes hidden requirements, power and the like as constraints is constructed on a hidden communication model of a transmitting end, a receiving end, an intelligent reflecting surface and a monitor. Firstly, the bit error rate of a receiving end is given, the detection performance of a monitor is analyzed, and the KL divergence upper bound and the corresponding hidden constraint are deduced. The objective function and the constraint set of the constructed problem are non-convex, the optimization problem is trained and solved by constructing the optimization problem into a deep reinforcement learning model, the modulation order which is difficult to optimize by a traditional algorithm is optimized by using the advantages of deep reinforcement learning, a deep deterministic strategy gradient algorithm is selected to train the model, and then the error rate is minimized. And the covert communication performance is improved.

The invention provides an FD-RIS assisted covert communication method and system. The covert communication system comprises a base station, an FD-RIS, a covert user and an eavesdropper. According to the covert communication system, a time modulation technology is utilized to modulate a reflection coefficient of each reflection unit of the FD-RIS, and time delay is introduced in the time modulation process of each reflection unit; the method comprises the steps that an optimization problem is solved, the optimization problem takes maximization of the reachable rate of a hidden user as an optimization target, time delay and time modulation frequency in each reflection unit are obtained with the time modulation frequency constraint of the FD-RIS, the time delay constraint of the reflection units in the FD-RIS and the hidden constraint as constraint conditions, and the time delay and the time modulation frequency in each reflection unit are obtained. According to the method, the concealment performance can be remarkably improved, and the challenge of'safety blind areas' faced by a traditional RIS auxiliary concealed communication system is dealt with.

The invention provides an unmanned aerial vehicle covert communication method and system supported by a movable antenna, and the method comprises the steps: calculating the maximum communication rate of a legal user under the support of the movable antenna according to a communication scene of the movable antenna; according to a movable antenna communication scene, calculating a minimum detection error rate under multi-illegal-guard cooperative detection; based on the maximum communication rate and the minimum detection error rate, a joint optimization problem of time slot segmentation, beam forming, unmanned aerial vehicle trajectory and movable antenna position is established, and the optimization objective is to maximize the minimum throughput of legal users under the condition of satisfying covert communication constraints; an iterative algorithm based on block coordinate descent and continuous convex approximation is adopted to obtain optimized time slot segmentation, beam forming, unmanned aerial vehicle trajectory and movable antenna position parameters, and the parameters are applied to covert communication of the unmanned aerial vehicle. According to the method provided by the invention, the concealment requirement of unmanned aerial vehicle communication can be well met, and the network security is improved.

The invention discloses a covert communication system based on a generative diffusion model, and belongs to the technical field of covert communication. In order to solve the problems of insufficient concealment and poor anti-noise performance in the prior art, hidden transmission and reliable recovery of information are realized by constructing a diffusion generation and classification discrimination module. The sending end carries out noise addition and shaping on the original bit waveform by using a forward diffusion process to form a noise-like hidden signal; and a receiving end recovers a signal structure through a reverse denoising process, and accurately judges bit information through a classifier. According to the method, a Gaussian approximation hidden waveform library is constructed by adopting a signal pair training model which is consistent in statistics but distinguishable in structure, and random sampling mapping and boundary smooth splicing are combined, so that transmission signals are difficult to distinguish from noise in a frequency domain and a feature space; therefore, the avoidance capability, the anti-interference robustness and the information recovery accuracy under the low signal-to-noise ratio of the detection means are remarkably improved.

The invention discloses an unmanned aerial vehicle ISAC system beam and three-dimensional trajectory joint optimization method for covert communication. Aiming at the condition that potential monitors exist in a network architecture in which an unmanned aerial vehicle performs downlink information transmission to a plurality of ground users, a communication system model is firstly constructed, and then an optimization problem conforming to a scene with user scheduling, a communication and sensing integrated waveform and an unmanned aerial vehicle flight path as constraints is constructed by taking maximization of an average covert communication rate of a system as a target; then, based on a BCD method, an original optimization problem is decoupled into sub-problems about user scheduling, a common inductance integrated waveform and a UAV three-dimensional flight path, and convex approximate fitting is carried out on each non-convex sub-problem; and finally, solving by adopting an iterative algorithm to find a global suboptimal solution of the whole optimization problem, an optimal sensing integrated waveform and a UAV flight trajectory. According to the invention, the security of information transmission is improved, the communication quality and concealment are maximized, and concealed transmission of information is realized.

The invention belongs to the field of information security, and relates to a robust video steganography method and system based on neighbor block difference cost, which can resist video transcoding of a social platform and is used for covert communication of a lossy channel. According to the method, a cost distribution method based on neighbor block difference is designed to evaluate the robustness of an embedded unit, a global robust modulation mode is selected by using a minimization distortion frame, and the embedded unit is modulated by adopting quantization index modulation according to the global robust modulation mode to embed secret information. The robust video steganography method and system provided by the invention integrate strategies such as adjacent block difference cost, an optimal robust modulation mode and a minimization distortion frame, and can effectively support robust video steganography communication under a social network lossy channel.

The invention provides a hierarchical medical scene-oriented dynamic interference cooperative communication optimization system and method, and relates to the technical field of medical data communication security. The hierarchical medical scene-oriented dynamic interference cooperative communication optimization method comprises the following steps: S1, based on hierarchical medical scene differences of emergency treatment, ICU and common wards, realizing covert communication by using native physiological data transmission mutual interference signals of multiple devices in a medical monitoring network; s2, different communication security thresholds and data timeliness indexes are set for different levels of scenes; and S3, constructing a dynamic interference coordination framework, and realizing interference intensity adaptation by adjusting the transmission power (Pi) of the medical equipment and the dedicated channel gain (hj, iva). According to the invention, through linkage with the HIS system, differentiated safety thresholds and timeliness indexes are set for emergency treatment, ICU and common wards, and priority requirements of different scenes are accurately met; parameter synchronization can be rapidly completed during cross-scene transfer, and the problem of connection lag of a traditional scheme is solved.

The invention discloses a bionic signal demodulation method based on a DSCAF-Net. The method comprises the following steps: receiving a bionic signal, then carrying out signal preprocessing, constructing a double-flow feature tensor, executing sample-level randomization sorting, carrying out global normalization processing, carrying out one-hot coding on a category label, and dividing a preprocessed data set into a training set, a verification set and a test set; a double-flow neural network architecture is constructed, and data is split into two independent channels such as a training sequence and a data symbol sequence through a double-flow separation module. According to the invention, through signal preprocessing, double-flow neural network architecture design and an optimized training strategy, key problems in an existing bionic covert communication system are effectively solved, and bionic signal demodulation with low bit error rate, low delay and high real-time performance is expected to be realized under a complex underwater acoustic channel condition; and a new thought and technical support are provided for the development of a bionic covert communication system.

The invention provides a covert channel communication flow identification method. The method comprises the following steps: acquiring a covert communication flow sample set; extracting data features and converting the data features to obtain data feature values, vectorizing the data feature values to obtain feature vector representation, extracting time sequence features of the covert communication flow sample set, identifying interaction mode features of the covert communication flow sample set, and fusing the interaction mode features to generate context feature vectors; splicing the context feature vector and the feature vector representation to obtain an enhanced feature vector; performing label distribution according to the communication behavior type of the covert communication flow to obtain a condition label; constructing a multi-head generator and a multi-head discriminator; training is carried out according to a set loss function to obtain a trained generator and a discriminator, a dynamic weight adjustment mechanism is set, and the discriminator is used for judging whether the flow data to be recognized is the real covert communication flow or not. By applying the method, the diversity, the accuracy and the calculation efficiency of covert communication flow detection are improved, and the method has obvious advantages.

The invention relates to the technical field of low-power wide area network communication and information hiding, and discloses a LoRa-based covert communication method, which comprises the following steps of: at a transmitting end, generating a key-driven perturbation sequence according to covert information to be transmitted, constraining perturbation parameters through an undetectable controller, and transmitting the perturbation sequence to a receiving end; performing symbol-level perturbation modulation on the linear frequency modulation slope of the LoRa signal, and embedding a low-speed synchronous beacon in a preamble symbol counting tolerance range; at a receiving end, conventional data is demodulated through a standard LoRa receiving process, a frequency offset residual error, a phase residual error and a symbol fitting error after de-spreading are extracted in parallel, related detection is carried out by using a key consistent with a sending end, and hidden information is extracted from a residual error domain; the undetectability controller dynamically adjusts perturbation magnitude and embedding density based on a distribution difference metric. The objective of the invention is to solve the problem that communication reliability and hidden undetectability are difficult to guarantee at the same time in a LoRa system.

The invention relates to the technical field of covert communication, in particular to a bionic covert communication method based on multi-sea-area dolphin voiceprint feature library matching, which comprises the following steps of: constructing a dynamic voiceprint feature library associated with sea area coordinates, dolphin species and voiceprints, and adjusting acoustic parameters in combination with real-time environment monitoring; communication information is encoded in a natural variation range of acoustic characteristics of the dolphin, bionic signals highly conforming to the sound scene of a target sea area are synthesized and emitted, low-recognizable and low-monitorable hidden data transmission between underwater equipment is achieved, meanwhile, false alarm of a marine mammal protection system is avoided, and the safety communication requirement of equipment such as an unmanned underwater vehicle is met.

The invention discloses a signal depth detection method, a signal depth detection device, signal depth detection equipment and a medium for a low interception waveform, and relates to the technical field of signal identification. According to the method, the covert communication signal can be effectively detected without using signal energy and periodic characteristics, so that the use of the signal energy and the periodic characteristics of the frequency domain is avoided, and the covert communication signal of variable parameter spread frequency hopping can be effectively detected under the condition of low signal-to-noise ratio.

The invention discloses a covert communication method and system assisted by a movable antenna in a communication-inductance integrated network, and the system comprises an ISAC base station which is provided with Nt movable transmitting antennas and Nr fixed receiving antenna arrays; k communication nodes, each of which is configured with a single antenna and is used for receiving a communication signal sent by the ISAC base station; the point-like sensing nodes are used for receiving the sensing signals sent by the ISAC base station; the eavesdropping node is provided with a single antenna and is used for trying to detect a signal sent by the ISAC base station; according to the invention, the movable antenna array is deployed in the covert communication system, so that the space coverage limitation of a traditional fixed antenna system can be broken through, and the wide-area coverage and deep penetration capabilities of communication services can be improved. The mobile antenna array network significantly enhances the transmission efficiency and link robustness of covert communication through multi-dimensional degree-of-freedom cooperative regulation and control such as precoding vector optimization, three-dimensional space position dynamic configuration and the like.

The embodiment of the invention provides a steerable antenna-based covert communication system transmission rate enhancement method and related equipment, and belongs to the technical field of wireless communication. The method comprises the following steps: introducing an antenna pointing vector and a deflection angle pair to represent the three-dimensional direction of a single steerable antenna, establishing a channel model related to the antenna deflection angle pair, and deducing a hidden rate expression of a legal user; deducing a hidden constraint condition expression of the illegal user side by using the channel model; according to the concealment rate expression and the concealment constraint condition expression, constructing a joint optimization problem taking maximization of the concealment rate of the legal user as a target and taking concealment constraint, transmitting power constraint and antenna steering angle constraint as conditions; and solving the joint optimization problem to obtain an optimized transmitting beam forming vector and a deflection angle pair of the steerable antenna. The antenna orientation is dynamically adjusted, the spatial degree of freedom is fully excavated, and the transmission rate of the system can be remarkably improved on the premise of strictly ensuring the communication concealment.

This application discloses an intelligent reflective surface and a covert communication system, belonging to the field of wireless communication technology. The intelligent reflective surface includes multiple intelligent reflective surface units arranged in an array; each intelligent reflective surface unit includes: a first substrate, a second substrate, and a third substrate; a metal patch and a varactor diode, located on the side of the third substrate opposite to the second substrate; the metal patch includes a first patch and a second patch, and the varactor diode is located between the first patch and the second patch, with its negative and positive terminals electrically connected to the first patch and the second patch, respectively; a metal ground plane, located between the first substrate and the second substrate; a first bias line and a second bias line, located on the side of the first substrate opposite to the second substrate; the first bias line is electrically connected to the metal ground plane and the first patch, respectively, and the second bias line is electrically connected to the second patch. This application can achieve precise control of electromagnetic waves, reduce electromagnetic energy loss, improve energy transmission efficiency, suppress electromagnetic wave leakage, and improve communication covertness.

The embodiment of the invention provides a signal transmission method and device of a movable antenna array and electronic equipment, and belongs to the technical field of antenna communication. The method comprises the following steps: determining a plurality of monitoring parties and at least two target receiving ends; one target receiving end is in a near-field communication scene, and the other target receiving end is in a far-field communication scene; constructing a communication model based on the movable antenna array, the plurality of monitoring parties and the target receiving end; performing reachable rate analysis and concealment analysis based on the communication model to obtain reachable rate related data and concealment related data, and then constructing a target optimization problem; the position of each movable sub-array of the movable antenna array is adjusted, power distribution of the movable antenna array is adjusted, a target optimization problem is processed, target optimization information is obtained, and therefore signal transmission operation of the movable antenna array is adjusted. According to the embodiment of the invention, joint optimization of the covert communication rate and the concealment can be realized under the condition of a mixed field domain channel.

This application provides a method and apparatus for detecting covert communication behavior, relating to the field of network security technology. On one hand, the method uses a dynamic time warping algorithm to determine the minimum cumulative distance between the packet length-timestamp sequence and the standard response traffic template sequence in the packet length dimension. This quantifies temporal misalignment differences, thus solving the problem of missed detection caused by the lack of temporal analysis capabilities in traditional methods. On the other hand, based on the arrival timestamp of the packet length-timestamp sequence, the method determines the differential entropy and the maximum time span of sudden events. The differential entropy can amplify the minute temporal fluctuations caused by the mechanical packet sending of tunnel traffic, while the maximum time span can identify deliberately lengthened idle periods in tunnel traffic. Combining these two methods can accurately capture gradual covert communication such as slow tunnels. Therefore, this method can improve the accuracy of detecting covert communication behavior.

A multi-party password book distribution method based on secret sharing, a sender uploads a password book to an interstellar file system through public key encryption, adopts secret sharing to secret split information obtained by splicing a public key and a Hash of an expected receiver, a receiver obtains a secret share through biological feature recognition technology, and obtains a sender public key through a judgment function to download an original password book from the interstellar file system. According to experimental results and security analysis, the scheme can guarantee high time efficiency and resist impersonation attacks, and guarantee the safe transmission of the password book. The present application solves the security problem of password book distribution by adopting a shamir threshold scheme, changes the threshold for safe password book distribution, dynamically solves the entry and exit of receivers, solves the problem that original covert communication can only perform one-to-one communication, and realizes one-to-many communication.

The invention provides a self-adaptive hybrid covert channel construction method based on dynamic flow perception, and belongs to the technical field of covert communication and network security. The method comprises the following steps: constructing a hybrid covert channel comprising a time sequence type covert channel and a storage type covert channel to transmit secret information; monitoring the flow condition of the network in real time and calculating the network congestion degree; determining the proportion of a time sequence type covert channel and a storage type covert channel in the mixed type covert channel based on the network congestion degree; segmenting the to-be-sent secret information according to the belonging proportion to obtain to-be-sent information of a time sequence type covert channel and to-be-sent information of a storage type covert channel; the time sequence type hidden channel to-be-sent information is sent through the time sequence type hidden channel; and sending the to-be-sent information of the storage type covert channel through the storage type covert channel. The method can adapt to changes of different network loads and crowdedness degrees, the reliability and concealment of data concealed transmission are guaranteed, and the requirements of two communication parties for safe communication are met.

The invention discloses a covert communication method based on a simultaneous transmission and reflection reconfigurable intelligent surface, and the method comprises the following steps: in a system, a base station sends an NOMA signal to a first communication user through a direct connection link and an ASTAR-RIS reflection link, and sends a signal to a second communication user through an ASTAR-RIS transmission link, the first communication user is used as an energy collection node to perform energy collection and signal decoding by using the SWIPT technology; and when the second communication user fails to decode successfully, the first communication user forwards a signal of the second communication user by using the collected energy, and the second communication user sends interference to the monitor at the same time to weaken the detection performance of the monitor. According to the method, ASTAR-RIS, NOMA and SWIPT technologies are combined, the communication spectrum efficiency and the energy utilization rate can be improved, meanwhile, the detection performance of a monitor is effectively reduced, and the reliability and the practical value of a covert communication system are improved.

The application discloses a method for realizing covert communication by using a terahertz high-speed data transmission, which combines information hiding technology with a terahertz high-speed data transmission system, uses original data of a terahertz high-speed data transmission channel as a carrier, carries out digital sampling on an analog signal which needs to be separately transmitted, modifies values of a data part of the carrier, matches the data to be hidden with a function value of the carrier data, hides marking information in the data containing the hidden information, and further improves quality of the carrier data at a receiving end, and saves channel resources for transmitting the analog signal. The information hiding process is carried out at a front end of the terahertz high-speed data transmission system, and does not change a terahertz wireless communication system. The hiding method is simple and flexible, and PSNR is improved by 3 dB compared with a least significant bit replacement method under the condition of the same hiding capacity.

The present invention discloses a probabilistic jamming UAV-assisted wireless covert communication method and system, comprising the following steps: constructing a transmission model and a communication process of the communication system; obtaining a signal received by a UAV, a forwarded signal of the UAV, and a forwarding amplification factor according to the transmission model and the communication process; during the signal forwarding process, a detector determines whether the UAV has signal forwarding by analyzing the transmitted signal of the UAV; the detector performs a binary hypothesis test based on the received signal, and obtains Willie's two detection error probability expressions according to the Neyman-Pearson optimal decision rule; constructing an optimization problem based on the effective concealment rate that can be obtained by the destination node under the condition that concealment constraints are met, and solving the optimization problem to obtain the maximized concealment rate; designing a source node function so that it sends probabilistic interference to confuse the detector's detection, thereby assisting the transmission of secret information, improving system performance through concealment performance constraints, and maximizing the final concealment rate that can be obtained.

The application discloses a UAV dynamic spectrum sensing and covert communication method suitable for resisting environment, and relates to the technical field of UAV communication; the application extracts a sensing quality index and an interference influence index based on initial interference signal characteristics, calculates a UAV single-machine fusion weight by combining an entropy weight method, dynamically weights and fuses single-machine sensing data of each UAV, and can further introduce an interference suppression factor to generate interference-spectrum double-feature fusion features to extract single-machine sensing data; the application can adaptively distribute fusion weights according to interference levels and sensing accuracy, avoids fusion errors caused by strong interference UAVs, fully develops the advantages of airspace diversity of multiple machines, significantly improves spectrum sensing accuracy and robustness, reduces multiple-machine data redundancy, and improves sensing real-time performance.

The invention relates to a high-security hidden communication system, and belongs to the technical field of information security. According to the system, the mark feature and the structural feature of encrypted data are eliminated through a strong encryption technology, the key feature of the encrypted data is eliminated, the key security is ensured, the ciphertext security is improved, and the risk problem brought by side channel analysis to the data encryption security is solved; a double-layer covert channel is realized through a multimedia steganography technology and a flow simulation technology, the concealment of communication behaviors is greatly enhanced, and the problem of insufficient concealment of a single-layer covert channel is solved; the hidden communication technology with both concealment and anonymity is realized by combining the hidden channel with the anonymous network, and the problems that the anonymous network has obvious traffic characteristics and network boundary nodes are easy to expose are solved.

The invention discloses a multi-user hidden networking method based on double time scale constraints. The method comprises the following steps: 1, slicing time-frequency network resources to obtain an available time-frequency slot set; 2, obtaining a basic random sequence M < k > under the action of a system clock and a user authentication key; 3, performing cyclic shift transformation on the basic random sequence M < k > to obtain an extended sequence family NL * K; step 4, carrying out orthogonalization processing on the extended sequence family NL * K to obtain a decision sequence family HL * K, and guiding multiple users to access the network; 5, authorized user access protocol performance analysis is carried out, and dual-time-scale constraint is carried out to achieve the optimal networking throughput; step 6, reliability and security analysis is carried out on the covert communication system; and 7, analyzing the tolerance of the covert communication system, and solving by using an improved SA-PSO algorithm. According to the method, multiple users are guided to asynchronously access the covert communication network through dynamic management and allocation of spectrum resources, and the method has the characteristics of high efficiency, flexibility, stability and accuracy.

The application discloses a kind of based on affine frequency division multiplexing covert communication method and system.The method includes: transmitting end and receiving end respectively carry out channel estimation, obtain channel state information, and construct frequency domain channel matrix;Using channel reciprocity, both sides independently generate the same Chirp parameter codebook, avoid eavesdropper reconstruction;Transmitting end generates corresponding modulation symbol according to the input modulation bit;According to the amplitude of the diagonal element of frequency domain channel matrix, index bit is selected to the starting position of the Chirp parameter codebook;Transmitting end carries out affine frequency division multiplexing modulation according to the Chirp parameter codebook selected by index bit to constellation symbol and transmits;Receiving end reconstructs Chirp parameter codebook using its own CSI and completes matching decoding and modulation decryption.The application realizes shared password book without the need of privacy information exchange, makes full use of waveform parameter degree of freedom, improves the spectral efficiency and communication security of system, and is suitable for high-speed mobile communication data covert transmission.

The application discloses a kind of transmission power optimization methods, products and equipment for multi-cooperative monitoring underwater acoustic covert communication, comprising: estimating when sending node sends preset symbol, each listening node listens to the received signal, according to received signal, the transmission power observed by each listening node is calculated, and then the decision statistics of each listening node is calculated;Select the fusion strategy corresponding to the underwater acoustic covert communication environment where it is located, fuse the decision statistics of each listening node to obtain joint decision statistics;Determine whether joint decision statistics meet preset condition, if yes, establish transmission power optimization model, the joint false alarm rate of multiple listening nodes cooperative monitoring is lowest as the goal of transmission power optimization model, with total communication throughput greater than or equal to preset threshold as constraint condition, transmission power is disturbed in each communication time slot Control;The optimal transmission power is obtained by solving.This application is applicable to underwater acoustic covert communication scene with multiple listening nodes.