65 results about "Phase Code" patented technology

The invention relates to the technical field of ultra-far offshore data transmission, and discloses an ultra-far offshore distance real-time data stable transmission method and system. The method comprises the following steps: acquiring target transmission link data, and extracting dynamic fluctuation characteristics containing signal strength distribution information and a delay jitter relationship from the target transmission link data; calling the trained channel estimation network to carry out signal positioning processing on transmission link data, and generating a signal transmission path set containing a channel type identifier and phase code mapping relation; based on the set, calling a waveform analysis network to perform multi-modal feature fusion on the signal intensity distribution information to obtain a fusion result containing time-frequency domain features and modulation mode features; and inputting a fusion result into a transmission strategy model to perform dynamic path selection, and outputting a real-time data transmission element containing a control instruction generated based on a signal transmission sequence and a phase self-calibration parameter. According to the method, stable transmission of real-time data under the ultra-far offshore distance can be realized.

This invention provides a phase code digital low-pass filter circuit and a re-timer based on a PI-based architecture. The phase code digital low-pass filter circuit includes a first accumulation unit and a downsampling decimation module. The first accumulation unit accumulates the initial frequency control information generated by the clock data recovery module of the re-timer to generate a phase signal. The downsampling decimation module downsamples the phase signal to generate a filtered phase code. The filtered phase code is used to generate the transmit channel clock. This invention effectively solves the problems of high implementation cost, large footprint, and easy introduction of additional analog non-ideal factors in existing digital filtering solutions.

The application provides a remote acoustic signal pickup method and system based on phase coding microwave sensing, comprising: constructing a phase coding matrix, and performing phase shift control on the transmission signals of multiple transmission antennas; controlling the multiple transmission antennas to simultaneously transmit a linear frequency modulation continuous wave signal, so that the main lobe of a synthesized beam is directed towards the direction of a to-be-detected acoustic source or the direction of a target medium; using one or more receiving antennas to receive echo signals of the acoustic source target, to obtain a corresponding number of baseband signals; performing acoustic vibration phase demodulation on the corresponding number of baseband signals, to extract vibration information of the surface of the medium target caused by the vibration information of the acoustic source or caused by the excitation of the acoustic wave; and reconstructing the acoustic signal, to realize remote acoustic pickup. The application overcomes the problems of weak echo signals, low signal-to-noise ratio, large adjacent target interference and low quality of reconstructed acoustic signals in remote acoustic pickup, and improves the signal-to-noise ratio and sensing distance of remote acoustic pickup.

Disclosed are techniques for wireless sensing. In an aspect, a sensing node receives, from a sensing entity, a. configuration to report interference measurements, obtains, at a first time, one or more sensing measurements of one or more first sensing reference signals transmitted by a transmitter sensing node, obtains, at the first time, one or more interference measurements of one or more second sensing reference signals transmitted by one or more aggressor sensing nodes, and transmits, to the sensing entity, an interference measurement report including at least the one or more interference measurements.

The present invention discloses a method for designing discrete constant modulus quadrature phase coding for multiple targets. The method comprises the following steps: S1: determining the number of waveform signals M and the number of code elements N of each waveform of a multi-input multi-output radar, and randomly generating training samples of a size of M×N; S2: calculating the distance of a range gate and the waveform correlation function, and setting a loss function based on the distance and correlation function; S3: inputting the training samples into an established phase coding network for training, performing modulo-1 and discretization processing on the network output to obtain discrete constant modulus phase coding; S4: calculating the coding loss value based on the loss function, and updating the network parameters based on the loss value; S5: proceeding to S6 upon completion of training, otherwise returning to S3; S6: obtaining a trained network, inputting the data to be coded into the trained network, and obtaining a discrete constant modulus quadrature phase coded signal. This method enables the multi-input multi-output radar to operate normally in multi-target scenarios, and the output is a discrete code, which is more suitable for practical applications.

Systems and techniques for wireless communication are disclosed. For example, a network device may transmit a sensing signal for sensing one or more targets. The transmitted sensing signal and at least one sensing signal transmitted by at least one other network device of the plurality of network devices include one or more phase codes and a same frequency modulated carrier (FMCW). Each phase code of each sensing signal corresponds to one or more Doppler spectrum patterns. A network device may receive at least one echo signal from one or more targets. The network device may mitigate Doppler ambiguity in the Doppler spectrum from the at least one echo signal based on the one or more Doppler spectrum patterns.

The invention discloses a composite modulation signal blind identification method based on time-frequency analysis, which comprises the following steps of: firstly, judging and classifying input pulse signals, and then respectively carrying out identification and parameter estimation on determined signal types. According to the scheme, down-conversion analysis processing, signal time-frequency analysis processing and signal classification identification decision processing are firstly carried out on AD sampling intermediate frequency data sent by a digital signal processing board FPGA to obtain an identification result of a radar signal intra-pulse modulation type, and then corresponding parameter estimation is carried out according to the radar signal intra-pulse modulation type. According to two composite modulation styles of frequency coding and linear frequency modulation combination and frequency coding and two-phase coding combination, on the basis of time-frequency parameter characteristics of various composite modulations, related characteristic parameters are accurately extracted, a modulation type identification process is constructed, and time-frequency analysis is performed on radar signals through fast Fourier transform and phase correlation, so that the identification accuracy of the radar signals is improved. And furthermore, intra-pulse parameter estimation is accurately carried out on the radar signal.

The invention provides a photoelectric oscillator capable of being used for generating tunable phase coding microwave pulses. The photoelectric oscillator is composed of a tunable laser, a polarization controller, a phase modulator, a dual-drive Mach-Zehnder modulator, an optical circulator, a phase shift fiber bragg grating, a single-mode fiber, a photoelectric detector, an electric amplifier, a microwave source and an arbitrary waveform generator. The invention develops the active mode-locked photoelectric oscillator for generating the phase-coded microwave pulse signal, which is simple in structure and good in tunability. On the basis of an active mode-locked optoelectronic oscillator, a phase modulator is driven by a phase coding signal, so that the duration of each voltage polar code is kept consistent with the loop delay of the optoelectronic oscillator, and a phase-coded coherent microwave pulse sequence is generated. The signal has the advantage of large time bandwidth product, can give consideration to the detection distance and distance resolution of the radar, and has the characteristics of interference resistance, low interception and the like.

The invention relates to an intermittent sampling forwarding interference identification method, and belongs to the technical field of electronic countermeasures. The emission waveform design mainly comprises phase coding waveform identification code design, intra-pulse orthogonal waveform optimization and signal splicing; the receiving time-frequency processing mainly comprises pulse compression processing and time-frequency transformation analysis on echo signals. The intermittent sampling and forwarding interference identification method provided by the invention has the main advantages that the radar interference identification emission waveform based on the identification code has advanced interference identification performance, and at least two types of intermittent sampling and forwarding interference can be identified more accurately.

The invention provides a quantum state coding device and method and a software-defined quantum communication system. The quantum state coding device comprises a polarization coding unit, a first optical coupling unit, a polarization-to-time phase coding unit, a first transmission optical path and a second optical coupling unit, the polarization coding unit is used for carrying out polarization beam splitting, polarization rotation and phase modulation on an input optical pulse and outputting an optical pulse in a polarization coding quantum state; and the polarization-to-time phase coding unit is used for converting the optical pulse of the polarization coding quantum state into an optical pulse of a time phase coding quantum state. And controlling the first optical coupling unit and the second optical coupling unit to output the optical pulse of the polarization coding quantum state or output the optical pulse of the time phase coding quantum state according to the quantum communication coding control instruction. According to the quantum state coding device and the quantum communication system, different coding requirements of the quantum communication system can be met by the same quantum state coding device.

The invention belongs to the technical field of metasurfaces and plane lenses, and particularly relates to a focusing metasurface lens with an anti-shielding function, the lens is composed of 40 * 40 units with the period of 7.5 mm, each unit comprises a top layer metal annular patch, a dielectric layer and a bottom layer metal patch, the relative dielectric constant of a dielectric substrate is 2.65, and the relative dielectric constant of the dielectric substrate is 2.65. The units realize anisotropic response through circumferential notch design, a stable 180-degree phase difference is formed by adopting a mirror image inversion structure, the 1-bit phase modulation requirement is met, the array performs phase coding in the radial direction according to an Airy function, and a hollow annular layout is adopted, so that the self-bending and self-repairing characteristics of Airy beams are effectively utilized, and the phase modulation efficiency is improved. The electromagnetic wave can bypass physical shielding of an axis area, field intensity reconstruction is realized at a set focus, and the design can remarkably improve focusing gain and energy recovery capability of a system in a shielding environment while maintaining high cross polarization conversion efficiency in Ku frequency band application of 13GHz and the like.

The invention provides a phase coding QKD (Quantum Key Distribution) method, which comprises the following steps that: a transmitting end modulates an optical pulse into four optical pulses, a receiving end modulates each optical pulse into four optical pulses and forms six interference pulses, and a quantum key is negotiated and shared based on the six interference pulses; the invention also provides a phase coding QKD system, which comprises a transmitting end and a receiving end and is used for realizing the phase coding QKD method disclosed by the invention. According to the invention, the code rate and the security of the QKD system can be obviously improved, and the method has a good application prospect.

The application relates to the field of electronic communication technology and discloses an information modulation method and system for an LLC resonant converter. The application provides an information modulation method for an LLC resonant converter, which comprises the following steps: a power control loop module of the LLC resonant converter outputs a target frequency through a period conversion module; a digital signal to be transmitted is decomposed into a symbol sequence composed of a symbol A and a symbol B in a split-phase code mode; a frequency change lookup table module is established according to the target frequency, the target frequency is input, and a frequency change amount is correspondingly output; in the encoding mode of the split-phase code, a preset delay time is inserted when the symbols are switched, and actual delay time and phase shift angle are obtained according to the relationship between frequency jump and phase; and the digital signal is modulated into the LLC resonant converter through a PFM module.

The invention discloses a deception jamming method and device for an azimuth phase coding SAR (synthetic aperture radar), and belongs to the technical field of electronic support system synthetic aperture radar countermeasure. The method comprises the following steps: intercepting an SAR signal, carrying out two-dimensional structured phase stripping by constructing an inverse distance modulation operator and an inverse azimuth modulation operator, and estimating to obtain an azimuth phase sequence; carrying out complex domain differential operation on the estimated azimuth phase sequence, constructing a phase consistency measurement index and minimum consistency order mapping, and identifying a coding structure of the phase consistency measurement index and the minimum consistency order mapping; constructing a linear least square problem based on an identification result, and reconstructing an azimuth phase sequence; and performing phase consistent modulation including convolution modulation on the intercepted signal to generate a deception jamming signal. According to the method, complete matching of the interference signal and the SAR receiving filter is realized, and effective deception interference can be implemented on a new system SAR adopting random, primary, secondary and grouped phase coding.

The present application discloses a method, device, equipment and medium for detecting the state of a motor based on coding, and the present application belongs to the field of manipulator technology. The method includes: receiving an electric pulse signal in real time; wherein the electric pulse signal is obtained by converting the optical signal passing through the shading plate; generating a detection code according to the electric pulse signal; determining the target phase according to the correlation between the detection code and the pre-constructed phase code and the motor phase; wherein the number of the phase codes is at least two; and determining the operating state of the motor according to the target phase. This technical solution converts the motor phase information into a phase code that can be accurately identified, which can effectively resist signal distortion caused by factors such as mechanical vibration and oil obstruction, has higher detection accuracy, stronger anti-interference ability and more flexible scalability, and provides reliable protection for the intelligent and precise operation of the manipulator.

Provided is a method for solving radar ambiguity and occlusion based on an orthogonal two-phase coded signal. The method includes: generating and optimizing an orthogonal two-phase coded signal set by means of a walsh matrix and a genetic algorithm, and alternatively, obtaining an orthogonal two-phase coded signal set through an exhaustive method, depending on a chip length; determining the radar period and the number m of transmission pulses in a period according to the radar farthest detection range and the pulse repetition interval (PRI), and selecting m signals from the orthogonal two-phase coded signal set, to constitute a group of orthogonal two-phase coded pulse signals; and accumulating echoes of transmitted pulse signals, to generate an echo matrix, performing frequency domain pulse compression, to obtain a processed new matrix, and performing moving target detection on the matrix.

Aspects of the present disclosure are directed to systems and methods of operating a MIMO radar system for automotive applications, including transmitting FMCW signals from first and second transmitters; wherein the signals each comprise a plurality of chirps, and each signal comprises phase modulation of the FMCW signal within each chirp by a respective CDMA phase code to produce respective first and second PM-FMCW signals; receiving a composite signal, wherein the composite signal comprises at least one reflection of the first PM-FMCW signal and the second PM-FMCW signal; and in the digital domain, processing a plurality of down-converted and pre-processed groups of samples of the composite signal by: applying a frequency response correction; applying a group delay filter; the CDMA phase code is removed; the 2D-FFT is applied; and removing a phase code cross-correlation residual from the corresponding transformed demodulated sample group by calculating an estimated residual and subtracting the estimated residual from the corresponding transformed demodulated signal.

The utility model discloses a quantum key distribution system with switchable coding modes. The quantum key distribution system comprises a laser, a transmitting end coding module, a receiving end coding module and a detection module, the sending end coding module comprises a first circulator, a first optical path converter, a first phase coding module and a first polarization coding module; and the receiving end encoding module comprises a second circulator, a second optical path converter, a second phase encoding module and a second polarization encoding module. The utility model discloses a quantum key distribution system with switchable coding modes, two coding modes of phase coding and polarization coding respectively have anti-polarization disturbance capability and anti-phase disturbance capability, the coding mode can be preferentially selected according to main environmental factors influencing bit error rate, and high-stability and high-performance operation of the system is realized. Meanwhile, by multiplexing the laser and the detection module, the engineering development cost of the QKD system is reduced, and the QKD system has higher on-site deployment value.

The application discloses a complementary sequence phase coding intermittent transmitting and receiving echo reconstruction method, and steps are as follows: first, complementary sequence intermittent transmitting and receiving control signal design; second, phase coding intermittent transmitting and receiving processing; third, phase coding echo reconstruction and information reconstruction. The method uses the characteristics of the intermittent transmitting and receiving control signal, and respectively processes the phase coding intermittent transmitting and receiving, so that the operation is convenient and simple, the reconstruction precision is improved, and echo information loss caused by the intermittent transmitting and receiving processing is solved.

The present invention discloses a modulation interference method, device, electronic device and medium for pseudo-random two-phase coded radar, belonging to the field of radar interference technology. The method comprises: acquiring multiple radar signals through electronic reconnaissance, establishing a radar carrier frequency list, a radar code sequence list, an interference signal code sequence list and a main lobe information list of the cross-correlation function between the interference signal code sequence and the radar code sequence; sampling the radar signal of the interference object, querying the radar carrier frequency list, the radar code sequence list, the interference signal code sequence list and the main lobe information list of the cross-correlation function between the interference signal code sequence and the radar code sequence based on the sampling result, determining the interference signal carrier frequency and the interference signal phase code sequence, and generating a modulated interference signal based on the interference signal carrier frequency and the interference signal phase code sequence. The present invention greatly improves the effectiveness of interference against pseudo-random two-phase coded radar.

The application discloses a multi-angle synthetic illumination super-diffraction imaging system and method based on coding modulation, relates to the field of optical imaging technology, and utilizes a spatial light modulator (SLM) to code and modulate a coherent illumination light field to realize the effect of similar angle-variable illumination without any mechanical device driving laser scanning. In addition, the application also freely adjusts the illumination spot size through phase coding to realize different illumination field angles, effectively avoids problems such as limited field angle and excessive dispersion of illumination energy and the like. The application can effectively improve the diffraction blur problem caused by the limited optical aperture in macro imaging, and the system is simple and compact, does not need high-precision displacement device assistance, and can realize a larger equivalent aperture and higher imaging resolution.

This application discloses a system startup status detection method, apparatus, storage medium, and device. The method includes: firstly, starting the target system using startup phase code, and obtaining the timestamps of the initialization completion times of each corresponding functional module using stub functions in the startup phase code; then, calculating the startup time of the target system using the timestamps; and obtaining startup status data corresponding to each core of the ECU during the startup process; and finally, generating a detection result of the target system startup status based on at least one of the startup time and startup status data of the target system. Because this application adaptively inserts stub functions into the startup phase code of the target system, it can obtain the timestamps of the initialization completion times of each functional module when starting the target system, thereby calculating the overall startup time of the target system more quickly and accurately, and thus improving the efficiency and accuracy of the target system startup status detection.

The invention discloses a conformal non-reciprocal amplitude and phase independent adjustable digital coding metasurface, the coding metasurface is composed of a plurality of units, accurate regulation and control of the phase and the amplitude of transmission electromagnetic waves can be realized simultaneously by adjusting the opening and the orientation of a C-shaped circular ring of a middle layer of each unit, and the phase and the amplitude are mutually independent. The unit material can be bent to realize conformality, and the super surface is a conformal coding super surface. Two metasurface units are arranged in a staggered mode, amplitude phases of the two metasurface units are coded respectively, then the metasurface is integrally bent, the metasurface achieves different function regulation and control on electromagnetic waves incident in the forward direction and the reverse direction, and the non-reciprocal conformal metasurface is achieved. The conformal and nonreciprocal amplitude and phase independent adjustable digital coding metasurface provided by the invention is conformal and nonreciprocal, can effectively improve the information capacity and degree of freedom of the metasurface, realizes multifunctional multiplexing, and has important application prospects in the fields of wireless communication, radar, imaging, signal processing and the like.

This invention discloses an angle-prior-assisted intelligent metasurface phase coding design method for two-dimensional DOA estimation. The method includes: constructing a system model for two-dimensional DOA estimation with a single receiving channel on the intelligent metasurface; deriving the explicit relationship between the CRB of the two-dimensional DOA estimation parameters and the phase coding matrix; utilizing the prior range information of the target two-dimensional angle, constructing a phase coding matrix optimization problem with a unit modulus constraint, aiming to minimize the average CRB; and efficiently solving this non-convex problem using the Riemannian manifold optimization algorithm to obtain the optimal phase coding matrix. This invention directly links the coding design to the theoretical performance lower bound. By optimizing the coding to focus beam energy in the target prior angle region, it significantly improves the accuracy of two-dimensional DOA estimation for azimuth and elevation angles within the angle prior range, reduces the required measurement overhead, and exhibits good robustness under one-bit phase coding.

The present invention discloses a method for separating range ambiguity of airborne MIMO-SAR using a combined transmit array and pulse coding. First, a transmit signal phase coding matrix is ​​constructed, and independent phase coding is added to the transmit signal of each transmitter within each pulse repetition period. Then, the echo data of each receiver is band-pass filtered in azimuth, thereby separating the echoes of the transmit signals of different transmitters scattered by ground targets. Subsequently, the echoes containing phase coding obtained in the above steps are phase decoded. Finally, a spatial filtering steering vector matrix is ​​constructed to separate the desired signal from the range ambiguous signal. The present invention phase encodes the transmit signals of different transmitters and, by taking advantage of the high pulse repetition frequency radar system, separates the transmit signals of each transmitter in the range Doppler domain. The present invention effectively utilizes the degrees of freedom brought by the transmitter array in the MIMO radar, and can effectively separate higher-order range ambiguous signals compared to traditional multi-receiver radars.

The application discloses a D8PSK modulation method and system based on phase coding space-time modulation super surface, specifically: a phase coding unit based on a reflective load phase shifter is constructed, eight discrete phase states are generated by regulating the reflective load impedance so that the phase coding unit generates eight discrete phase states; the phase coding unit is used as a super surface unit, and a phase coding space-time modulation super surface is obtained by arrangement; a D8PSK modulation signal model based on the phase coding space-time modulation super surface is established, information transmission of non-synchronous demodulation is realized while the carrier is space-time modulated; 3-bit information coding and modulation code rate are designed according to the transmission information, different modulation code rates are set as keys to realize encrypted information transmission; a receiving antenna receives a return signal, the return signal is demodulated through the key to realize acquisition of the encrypted information. The application improves the spectrum utilization rate of the space-time modulation super surface, realizes high-speed and stable information transmission, and meets the data security requirements.

The invention provides a light-operated phase coding hybrid beam forming system. The light-operated phase coding hybrid beam forming system comprises a phase coding module, an optical true delay module and an antenna array module, the phase encoding module is used for generating a phase encoding signal with a time-varying slope; the optical true delay module is connected with the output end of the phase encoding module and is used for dividing the phase encoding signal into multiple links and respectively providing incremental fixed delay for the multiple links so as to enable the phase encoding signals of the adjacent links to form controllable phase difference; and the antenna array module is connected with the output end of the optical true delay module and is used for determining the beam direction according to the phase difference and switching the beam direction by switching the phase time-varying slope. A time-varying phase coding signal with an adjustable slope is generated in a phase coding module, incremental fixed delay is introduced in cooperation with each link of an optical true delay module, so that initial phases of different links are located at different positions of a time-varying phase, a fixed phase difference exists between adjacent links, and finally, final beamforming is realized in an antenna array module.

The invention relates to the technical field of industrial process measurement and automatic instruments, in particular to a frequency-modulated continuous wave radar storage tank liquid level measurement method which comprises the following steps: acquiring an orthogonal baseband signal and generating a complex distance spectrum based on an uphill linear frequency-modulated signal, a downhill linear frequency-modulated signal and complementary phase coding; extracting reference echoes to calibrate the complex distance spectrum and determine a coding phase alignment angle, and subtracting the fixed structure echoes by using the fixed structure echo dictionary to obtain a fixed structure echo stripping complex distance spectrum and generate residual energy; complementary phase coding coherent combination is carried out based on the coding phase alignment angle, and candidate distance observation and candidate feature vectors are generated according to time delay consistency; and outputting liquid level estimation and confidence coefficient by adopting dynamic programming, performing change point detection on residual energy to generate a dictionary freezing mark and a dictionary rollback mark, generating an active disambiguation control instruction by combining the confidence coefficient, and updating emission scheduling parameters. The false peak and jump are effectively reduced, and the measurement stability and the adaptive anti-interference capability are improved.

Disclosed are techniques for wireless sensing. In an aspect, a sensing node receives, from a sensing entity, a configuration to report interference measurements, obtains, at a first time, one or more sensing measurements of one or more first sensing reference signals transmitted by a transmitter sensing node, obtains, at the first time, one or more interference measurements of one or more second sensing reference signals transmitted by one or more aggressor sensing nodes, and transmits, to the sensing entity, an interference measurement report including at least the one or more interference measurements.

The invention provides an automobile millimeter wave radar interference suppression method based on slow time phase coding, and the method achieves a better coherent interference suppression effect through optimizing the phase coding between adjacent pulses based on the idea of reinforcement learning. The method mainly comprises the following steps: establishing a Markov decision process of an automobile millimeter wave radar in a coherent interference suppression scene; deriving a Markov decision process reward function in the interference suppression scene; designing an observation matrix in a Markov decision process in a coherent interference suppression scene according to cumulative observation of a plurality of time steps; designing a reinforcement learning algorithm according to an inter-pulse phase coding scene to obtain action sampling output meeting reasonable probability distribution; designing a strategy network and a value network in combination with the observable problem of the environment part; training parameters are set, the network is trained, the trained network is used as decision output of coherent interference suppression, and result evaluation is carried out.