51 results about "Chaotic synchronization" patented technology

The invention discloses a method for generating a variable parameter chaotic signal, and a chaotic secure communication system. The method comprises the following steps: firstly, chaotic mapping is used to generate the chaotic signal; then a parameter set of the chaotic mapping is determined in advance, so as to process any pseudorandom signal, and enable the state of the pseudorandom signal and the elements of the parameter set to be in one-to-one correspondence; and a corresponding parameter is chosen to generate the variable parameter chaotic signal by chaotic mapping according to the state of the pseudorandom signal. The system comprises a chaotic signal generating module, an analog-to-digital conversion module, a parameter transformation module, a coding module, a multi-path choice switch, an encryption/decryption module, an encrypted message data cache, a plaintext data cache and a control module. The invention can increase the complexity of the output of the chaotic signal or a chaotic sequence, and effectively resist the analysis of the nonlinear prediction technology based on phase-space reconstruction. The output digital chaotic sequence can be taken as a pseudorandom number sequence or key stream to encrypt data; the output continuous chaotic signals can be used for designing a secret communication system based on chaos synchronization .

A robust hyper-chaotic encryption-decryption system, for digital secure-communication from a transmitter to a receiver, utilizing two robust hyper-chaotic means in the transmitter and receiver respectively, wherein the transmitter includes a hyper-chaotic signal generator and a transmitter's adjusting parameter device, and the receiver includes a hyper-chaotic synchronization receiver and a receiver's adjusting parameter device. A method is also disclosed, comprising an encryption and a decryption process wherein the encryption process including steps of decomposing a plaintext message into a sequence and carrying the sequence into a masking sequence of a hyper-chaotic signal via an XOR operation for generating a hyper-chaotic ciphertext, and the decryption process including steps of generating unmasking sequence of a hyper-chaotic signal to realize synchronization with the masking sequence after receiving the ciphertext and transforming the ciphertext into a decrypted plaintext massage via an XOR operation.

The objective of the invention is to provide a method of chaotic hybrid self-synchronization. Both communication sides get digital signal after sampling and analog-digital conversion of local continuous chaotic signal respectively at regular intervals. Sender executes pulse synchronization to continuous chaotic system with received digital signal and then transmits error correction signal including 1bit information to receiver. Receiver executes pulse synchronization to its continuous chaotic system with corrected digital signal. Continuous chaotic system at different location only need to transmit error correction information of 1bit to keep long period of steady synchronization through the synchronization method. Occupation rate to channel by redundant information fall to low and anti-attack ability of chaotic system is improved efficiently. The digital chaotic sequence output by chaotic system that synchronized through the invention can be used to encrypt data as pseudo-random sequence or key stream; the output continuous chaotic signal can be used to design encryption communication system that based on chaotic synchronization.

The invention belongs to the technical field of key distribution in secure communications, relates to a secure and high-speed key distribution scheme, and especially provides a secure and high-speed key distribution system and a method thereof based on a chaotic synchronization common channel feature. The system comprises a wideband random light source, a main fiber coupler, a common channel, an ultra-short pulse mode-locked laser, an Alice communicating party, and a Bob communicating party, wherein the Alice communicating party comprises a first optical feedback chaotic semiconductor laser, afirst fiber coupler, a first optical switch, a first privacy key module, a first register, and a first key filter; and the Bob communicating party comprises a second optical feedback chaotic semiconductor laser, a second fiber coupler, a second optical switch, a second privacy key module, a second register, and a second key filter. The invention is reasonable in structure, clever in design, effectively guarantees the key distribution security, and adequately uses the bandwidth advantage of a chaotic optical signal, which greatly improves the key distribution rate, and is appropriate for secure communication.

The invention discloses a chaotic laser communication system with a high secrecy space, comprising a transmitting end, a receiving end and a temperature control system. The transmitting end and the receiving end adopt an opto-feedback type structure; encryption on the hardware is used for realizing chaotic synchronization and information demodulation. The temperature control system realizes the synchronous and real-time control of the temperature of a Mach-Zehnder electro-optic modulator at the transmitting end and the receiving end through the terminal and the control modules of the transmitting end and the receiving end. Since the temperature of the modulator changes dynamically during communication, the difficulty for an eavesdropping party to crack information is increased as mismatchof the temperature of the modulator causes mismatch of a modulator operating point, which further makes the error rate increase even in the case that other parameters of the chaotic system are cracked. The chaotic laser communication system with high secrecy space in the invention can improve the secrecy performance of the existing chaotic system and has important significance for national defensesecurity and information security.

The invention relates to a communication system based on superlattice chaotic synchronization. The communication system based on superlattice chaotic synchronization includes a raw information generating device, a first chaotic signal generating device, a modulating device, a demodulating device, a second chaotic signal generating device and a raw information receiving device. The first chaotic signal generating device and the second chaotic signal generating device are both chaotic signal generating circuits based on superlattice devices and circuit parameters are coupled with each other. The first chaotic signal generating device generates a first chaotic signal. The modulating device modulates raw information according to the first chaotic signal. The second chaotic signal generating device generates a second chaotic signal that is synchronous with the first chaotic signal. The demodulating device demodulates the modulated information and a demodulated signal is obtained. According to the invention, circuit parameters of the chaotic signal generating devices at a transmitting end and a receiving end are coupled with each other, so that synchronous random numerical code streams can be produced and automatic synchronization of the transmitting end and the receiving end can be realized. The raw information cannot be decoded even when a third part knows the parameters of the transmitting end and the receiving end.

The present invention discloses a secret key distribution device based on chaos synchronization. The device comprises a chaotic signal generation module, an analog-to-digital conversion module, and an error correction module. The chaotic signal generation module inputs an excitation signal, and outputs a random chaotic analog signal; the analog-to-digital conversion module inputs the random chaotic analog and outputs a random chaotic digital signal; the error correction module inputs a random chaotic digital signal, namely a secret key, in accordance with the random chaotic digital signal; and the chaotic signal generation module, the analog-to-digital conversion module, and the error correction module are successively connected. In the device, the sender and the receiver enable secret key spread and distribution without information sharing before a ciphertext is sent and received. The confidential capacity is unrelated to computing power. The sender and receiver only need this device to enable secret key distribution.

The invention provides a method for detecting weak periodic signals under a strong noise background in a chaotic synchronization mode. The method comprises the following steps that a self-adaption chaotic synchronization signal detection system is constructed; reference signals are introduced in the driving end and the response end of a chaotic synchronization system; relevant parameters of the system are adjusted, and the driving end and the response end run in a chaotic state; signals to be detected are introduced in the driving end of the chaotic synchronization system, adjusting signals are introduced in the response end, and the running state of the synchronization system is determined; parameter correction is carried out according to the synchronization error of the driving end and the response end, and the amplitude values of the weak periodic signals to be detected are determined. The influence of noise and other factors to signal detection is lowered, the state can be judged fast and accurately, and approaches the periodic signals submerged in the noise, and detection precision and efficiency are effectively improved.

The invention belongs to the technical field of secure high-speed key distribution, and particularly relates to a high-speed key security distribution system and a method thereof based on aperiodic chaotic synchronization, wherein the system includes an Alice communication party and a Bob communication party, and both of the communication parties include a semiconductor laser, a polarization controller, a fiber coupler, a power meter, an optical attenuator, an oscilloscope, and a chirped fiber grating. The communication parties of the first embodiment further include a phase modulator, and thecommunication parties of the second embodiment further include an optical switch and a delay line. The invention has a reasonable structure and a clever design, and the key distribution method is reliable in principle, strong in implementation, and easy to operate. When communicating by using the method provided by the invention, the exchange of private keys is not required in the process of keydistribution, which avoids the problem of security threat caused by the leakage of some private keys, and further ensures the security of key distribution.

The invention discloses a chaos radar system using chaos synchronization which contains: microwave chaos signal circuit, power distributed device, the first amplifier, transmitting antenna, digital control microwave delaying circuit, receiving antenna, the second amplifier, self-adapting filter circuit, chaos prediction circuit, relative circuit, signal processing unit and electrical source. The signals generated by the microwave colpitts chaos circuit are the signals of radar source, a part of the chaos signals become the transmitting signals, a part engender delaying via the chaos circuit. When the echo signals are received, the echo signals drive the microwave chaos circuit which is as the chaos synchronization, and the output synchronizing signals correlate the local delaying signals to detect the parameters of position and velocity of the radar target.

Since chaos synchronization system possesses self-hold characteristic, the invention uses the principle of time-sharing sending by using the said characteristic, i.e., in time-sharing mode, cryptograph signal and chaos synchronization signal are sent out. As long as time for sending cryptograph signal is smaller than self-hold time of chaos synchronization system, chaos synchronization control signal is sent out in succession. Thus, it is guaranteed that reliable information transmission is accomplished under condition that chaos system keeps synchronization.

The invention discloses a long-distance laser chaotic synchronizer based on all fibers. The synchronizer is divided into two major modules, i.e., an external transmission module and a Fiber environment module. Light is injected to a Fiber environment, through adjusting an optical phase in the Fiber environment, laser chaos output is divided into two same portions, one portion is fed back to SL1 via a fiber link LDFL1, and the other portion is injected to SL2 via a fiber link LDFL1. When the fiber link LDFL1 and the fiber link LDFL1 maintain symmetrical and the SL1 and the SL2 have similar internal parameters, in case of proper working conditions, laser chaos can be generated. Besides, by use of the Fiber environment, the SL1 and the SL2 can simultaneously receive injected light and feedback light, and corresponding polarization modes can realize high-quality chaotic synchronization. The chaotic synchronization based on the corresponding SL1 and the SL2 can help to realize bidirectional long-distance laser chaotic secret transmission of information.

The invention belongs to the technical field of secret optical communication, and particularly relates to a long-distance secret key distribution system based on chaos synchronization, which solves the technical problems in the background technology, and comprises a one-drive-two communication structure consisting of a drive part and two communication parties, or a two-drive-two communication structure consisting of two drive parts and two communication parties which are respectively connected. A digital optical signal is used as a driving signal, the synchronization state of a laser output signal is responded through phase regulation of keying injection light, in the process, the digital signal is used as the driving signal for long-distance transmission, the influence of noise in a link on the digital signal is low, the synchronization quality is improved, the key distribution distance is increased, the system can be used for long-distance transmission, and the long-distance synchronization quality is improved.

The invention provides a bidirectional long-distance secure communication system based on silicon photon chaotic synchronization. the main silicon photonic chip generates a chaotic driving signal; thechaotic driving signal is amplified by an amplifier, passes through a first polarized light beam splitter and is equally divided into two same light beams; the light beams are transmitted through a first long distance optical fiber and a second long-distance optical fiber; a first slave silicon photonic chip and a second slave silicon photonic chip which are symmetrical are injected at the sametime; Chaos generated by the master silicon photonic chip serve as seed signals to drive the first slave silicon photonic chip and the second slave silicon photonic chip to achieve chaotic synchronization, information is added into the two synchronous slave silicon photonic chips respectively, and bidirectional information communication is conducted. According to the invention, bidirectional long-distance chaotic secure communication can be realized.

A generalized chaotic synchronization method for controlled Lorenz system and Finance system applied to secure communication comprises the following steps: 1) description of the generalized chaotic synchronization problem; 2) state transformation and feedback of the response system; 3) state transition of driving system; 4) Generalized synchronization. The invention provides the generalized chaotic synchronization method for controlled Lorenz system and Finance system applied to secure communication, the Finance chaotic system is a driving system and the single input controlled Lorenz system is a respondence system, a chaotic synchronization algorithm based on the Lie derivative of vector field in differential geometry is designed, The generalized synchronization is realized and the control quality is high.

The invention relates to a chaotic synchronization control method, and belongs to the field of nonlinear science. According to the chaotic synchronization control method, a training sample number setis obtained by solving a main system, a fitness function of the main system and a fitness function of a slave system are established by combining the slave system and an unbiased least square supportvector machine, and a hybrid synchronization trajectory and a control input signal are obtained; and parameters of a kernel function used in unbiased least squares are obtained through a particle swarm algorithm to obtain optimal parameters, and then hybrid synchronous control of the master and slave systems is achieved by using the designed control input signal. According to the chaotic synchronization control method, the calculation mode can be simplified, and the calculation precision is effectively improved.

The invention discloses a device and a method for enhancing the safety of a co-driven chaos synchronization system, and relates to the technical field of chaos communication carriers, and the device comprises a transmitting end, a first receiving end, a first dispersion compensation device, a second receiving end and a second dispersion compensation device. The transmitting end generates a main chaotic signal, divides the main chaotic signal into a first path of main chaotic signal and a second path of main chaotic signal, and sends the first path of main chaotic signal and the second path of main chaotic signal to the first receiving end and the second receiving end; a first receiving end receives a first path of main chaotic signal, and after the first path of main chaotic signal is processed by a first dispersion compensation device, a first path of slave chaotic signal is generated; and the second receiving end receives the second path of main chaotic signal, and after the second path of main chaotic signal is processed by the second dispersion compensation device, a second path of slave chaotic signal is generated to realize chaotic synchronization with the first path of slave chaotic signal. According to the invention, two paths of chaotic signals with flat frequency spectrums and no time delay characteristic can be generated, high-quality chaotic synchronization is realized, and the safety of a co-driven chaotic synchronization system is improved.

A generalized chaotic synchronization method of controlled Finance system and Chen system applied to secure communication is disclosed. The method comprises the following steps: 1) description of generalized chaotic synchronization problem; 2) state transformation and feedback of the response system; 3) state transition of driving system; 4) Generalized synchronization. The invention provides thegeneralized chaotic synchronization method of the controlled Finance system and the Chen system applied to secure communication, a chaotic synchronization algorithm based on Lie derivative of vector field in differential geometry is designed, which is driven by Chen system and responded by controlled Finance system with single input. The generalized synchronization is realized and the control quality is high.

The invention discloses a generalized synchronization method for a controlled Lv system and a Finance system for secrete communication. The method comprises the following steps: 1), description of a generalized chaotic synchronization problem; 2), state transformation and feedback of a response system; 3), state transition of a drive system; 4), generalized synchronization. The invention providesthe generalized chaotic synchronization method for the controlled Lv system and the Finance system for secret communication. The Finance chaotic system is used as the drive system, and the single-input controlled Lv system is used as the response system. A vector field Lie derivative method in the differential geometry is used for designing the chaotic synchronization method, thereby achieving generalized synchronization and high control quality.

The invention relates to a generalized synchronizing method of isomer time-delay chaotic systems. The generalized synchronizing method of the isomer time-delay chaotic systems is based on a functional differential equation stability theory and a generalized chaotic synchronizing method is used, so that generalized synchronization of the two isomeric two-dimension time-delay chaotic systems is achieved. The generalized synchronizing method of the isomer time-delay chaotic systems is easy to achieve and has wide application prospect and important practical value in the fields of radars, secret communication, electronic countermeasures and the like.

A Generalized synchronization method for controlled Finance system and Genesio-Tesi system applied to secure communication comprises that follow steps: 1) describing of a generalized chaotic synchronization problem; 2) state transformation and feedback of the response system; 3) state transition of driving system; 4) Generalized synchronization. The invention provides the Generalized synchronization method for controlled Finance system and Genesio-Tesi system applied to secure communication, The Genesio-Tesi system is the driving system, and the controlled Finance system with single input isthe responding system. A chaotic synchronization algorithm is designed by using the method of state space transformation, which realizes the generalized synchronization and has high control quality.

The invention discloses a secret communication method based on double-end deployment multi-layer time-delay reserve pool calculation, which comprises the following steps of: simultaneously deploying a time-delay reserve pool calculation model formed by a plurality of series-connected time-delay reserve pools to a receiving end and a sending end, and simultaneously training the time-delay reserve pool calculation models of the receiving end and the sending end by adopting a training set L (t); the sending end chaotic system continuously generates a new chaotic signal, the Ux (t) is reserved as a drive set to drive the time-delay reserve pool calculation model of the sending end to obtain a chaotic sequence Uz (t) for encryption, and meanwhile, the Ux (t) is sent to the time-delay reserve pool calculation model of the receiving end to synchronously generate a chaotic sequence for decryption consistent with the Uz (t); the sending end encrypts communication data to be transmitted by adopting the chaos sequence for encryption; and the receiving end decrypts the received encrypted communication data by adopting the chaotic sequence for decryption. According to the invention, high-quality chaos synchronization of the transmitting end and the receiving end can be realized, so that transmitted useful information can be stably demodulated.