127 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.

The invention discloses a two-dimensional modulation interference signal generation method and device, a storage medium and equipment, and belongs to the technical field of radar countermeasure. The method comprises the following steps: a jammer detects and receives a target SAR signal and converts the target SAR signal into a digital SAR signal; generating a phase coding modulation signal and a distance direction frequency shift modulation signal according to the required interference type and the signal parameter; generating an azimuth sine function secondary modulation signal and an azimuth frequency shift modulation signal according to a required interference type and a signal parameter; based on the various generated modulation signals and the digital SAR signals, range modulation and azimuth modulation are completed, and digital interference signals are obtained; and converting the digital interference signal into an analog interference signal, and forwarding the analog interference signal to the target SAR system. According to the invention, distance-direction phase coding modulation, azimuth-direction quadratic sine function modulation and two-dimensional frequency shift modulation are combined, six different types of two-dimensional interference effects can be flexibly generated, and the central position of the interference result can be accurately controlled.

The embodiment of the invention provides a phase calibration method, a phase calibration device and a storage medium, the phase calibration method is used for obtaining a phase step and a phase code table used for phase calibration of a phase shifter, and the phase calibration method comprises the following steps: presetting a first phase code table which comprises a plurality of phase codes, traversing a preset phase step combination by using the first phase code table to perform phase calibration, transmitting a preset waveform signal by using a calibrated phase code, judging whether the performance index of the preset waveform signal accords with a performance index threshold value or not, and taking the phase step combination of which the performance index accords with the performance index threshold value as an optimal phase step; and performing phase calibration on a plurality of groups of transmitting antennas by adopting the preferred phase step and one or more second phase code tables, and obtaining a third phase code table by taking part or all of phase codes obtained after the phase calibration of the plurality of groups of transmitting antennas. The optimal phase stepping is obtained by combining the waveform performance indexes, so that the transmitted waveform is closer to the expected waveform, and better calibration precision is obtained.

To provide mechanisms for providing a source for circular-ranging OCT at moderate speeds.SOLUTION: A source for providing electromagnetic radiation within a particular spectral range includes: a ring-shaped optical resonator for circulating a plurality of wavelength bands including a first optical phase modulator, a first chromatic dispersion device, a second optical phase modulator, a multi-line spectral domain filter, a second chromatic dispersion device, and an optical amplifier; and a controller coupled to the first optical phase modulator and the second optical phase modulator, the controller being configured to drive the first optical phase modulator with a first waveform and the second optical phase modulator with a second waveform.SELECTED DRAWING: Figure 2

The invention discloses a motor state detection method, device and equipment based on coding and a medium, and belongs to the technical field of manipulators. The method comprises the following steps: receiving an electric pulse signal in real time; wherein the electric pulse signal is obtained by converting an optical signal passing through the light shielding plate; generating a detection code according to the electric pulse signal; determining a target phase according to the detection code and a pre-constructed association relationship between a phase code and a motor phase; wherein the number of the phase codes is at least two; and determining the running state of the motor according to the target phase. According to the technical scheme, the motor phase information is converted into the phase codes capable of being accurately recognized, the signal distortion situation caused by mechanical vibration, oil stain shielding and other factors can be effectively resisted, higher detection precision, higher anti-interference capacity and more flexible expansibility are achieved, and reliable guarantee is provided for intelligent and accurate operation of the mechanical arm.

The invention belongs to the technical field of phase delay, and particularly discloses a laser phase encoder for coherent detection and imaging, which comprises a phase delayer, the phase delayer comprises a first reflecting mirror and a second reflecting mirror, the first reflecting mirror and the second reflecting mirror are oppositely arranged to form a phase delay cavity, and the first reflecting mirror and the second reflecting mirror are arranged in parallel. Light input into the phase delayer is propagated in the phase delay cavity, the second reflector is provided with a fused biconical taper, the output end of the phase delayer is connected with a Bragg grating, at least two optical fiber rings are carved in the Bragg grating, the fused biconical taper is coupled with the two optical fiber rings, and the two optical fiber rings correspond to an input port and an output port of the Bragg grating respectively. When the optical paths of the sample light and the reference light are equal, an interference phenomenon can occur; the sample light is long in transmission distance and is in a changing state, and the phase delayer is used for the reference light to form phase coding so as to match all paths of the sample light. Wherein one of the two paths of input light is subjected to phase delay through a phase delayer, so that the optical path difference caused by the irradiation of the detection light to an object is matched, and an interference phase expansion condition is achieved.

The invention discloses a metasurface control architecture design method. According to the method, high and low voltages of each row unit and each column unit of the metasurface array are coded, phase codes of the metasurface array are obtained through a matrix multiplication method, and the control architecture method is called a basic cross control method or a one-area cross control method. Furthermore, according to the method, the metasurface array is divided into a plurality of areas of the basic cross control architecture, so that a multi-area cross control architecture is formed; according to the multi-zone cross control, the number and the zone positions of the zones can be flexibly changed according to the requirements of an actual application scene, so that the pointing precision of a wave beam is regulated and controlled, and meanwhile, the achievable complexity of metasurface control hardware is reduced. According to the invention, on the premise of keeping the specified beam regulation and control precision, the complexity of a metasurface control architecture and the memory occupied space of coding can be obviously reduced, and the application development of the low-cost and high-performance reconfigurable metasurface is promoted.

The invention discloses a low sidelobe constant modulus phase coding sequence set design method. The method comprises the following steps: S1, carrying out random initialization on a constant modulus phase coding sequence set according to an expected signal parameter; s2, constructing a minimum sidelobe horizontal objective function based on a p norm and performing simplification; s3, deriving the gradient of the target function relative to the constant modulus phase coding sequence set; and S4, solving the minimization problem of the target function by using a conjugate gradient descent algorithm to obtain a low-sidelobe constant-modulus phase coding sequence set. According to the constant modulus sequence set design method disclosed by the invention, the design of a low-sidelobe single waveform and a multi-orthogonal waveform can be realized at the same time, and by changing the value of p, the method can meet the requirements of integral sidelobe level minimization and peak sidelobe level minimization sequence set design at the same time. The method provided by the invention not only can obtain a very low related sidelobe level, but also has very high calculation efficiency, and has a wide application prospect in pulse system radars.

The invention discloses a signal processing method based on space-time code-phase code multi-station radar orthogonal waveform design, and belongs to the field of signal processing. The signal processing flow comprises space-time code demodulation, matched filtering, pulse accumulation, MTI and MTD, each radar carries out space-time code demodulation on received echo signals, so that each pulse coefficient of radar echoes of the radar is 1, the sum of continuous N (needing to be a positive integer power of 2) pulse coefficients of other radar echoes is 0, then subsequent matched filtering is carried out, each N pulses are accumulated, and the sum of the N pulse coefficients of the other radar echoes is 0; therefore, echo cancellation from other radars is realized, interference from the echoes from other radars is reduced to a great extent, the speed measurement precision is not influenced by the processing mode, but the speed measurement range is influenced, and the influence on the speed measurement range can be ignored by designing the space-time code matrix and the pulse accumulation mode. Therefore, good anti-interference capability is achieved.

The invention discloses a radar signal modulation type classification method based on pulse compression characteristics. The pulse compression characteristics of radar signals are utilized to calculate signals, signal squares, signal quadruplicate after-pulse-compression main lobe width and pulse width ratio recognition, simple signals, two-phase coded signals and four-phase coded signals. Different delay autocorrelation coefficients are adopted for the remaining classified signals to calculate the modulation slope of the signals, and linear frequency modulation signals and nonlinear frequency modulation signals are distinguished according to the calculated modulation slope result. According to the method, simple signals, two-phase coded signals, four-phase coded signals, linear frequency modulation signals and non-linear frequency modulation signals can be distinguished through convolution operation and other simple operation by utilizing the pulse compression characteristics of radar signals; compared with other algorithms, the method has the advantages of small calculation amount, high recognition speed, simple process and low signal-to-noise ratio requirement.

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.

The invention provides a time phase coding device and method and a quantum communication system, and the device comprises a polarization coding unit and a polarization-to-time phase coding unit which are connected in series, and the polarization coding unit comprises at least one adjustable circular birefringence module. The adjustable circular birefringence module is used for converting one path of input optical pulse into two orthogonal linear polarization components, splitting the two orthogonal linear polarization components into two paths of sub-optical pulses, performing phase modulation on the two paths of sub-optical pulses by using a phase modulator, enabling the two paths of sub-optical pulses to generate a phase difference, and then combining the two paths of sub-optical pulses to be output; the polarization-to-time phase coding unit is used for converting the optical pulse output by the adjustable circular birefringence module into an optical pulse in a time phase coding quantum state, and converting the two orthogonal linear polarization components into a circular polarization component to be output, and the polarization-to-time phase coding unit is used for converting the optical pulse output by the adjustable circular birefringence module into an optical pulse in a time phase coding quantum state. The quantum communication security requirement is met, the number of used lasers is reduced, and the weight and power consumption of a transmitter are reduced.

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 automatically determining optimal bi-phase codes that have an autocorrelation value below a predetermined threshold. The optimal bi-phase codes are determined using a gate-based quantum circuit of a quantum computer consisting of qubits as state input variables, whose states represent possible bi-phase codes. This is achieved by: - ​​calculating the autocorrelation of the states of the state input variables, which contain the possible combinations of bi-phase codes, in several discrete steps; and - identifying a bi-phase code as optimal if the autocorrelation value in all successive discrete steps of the autocorrelation calculation is less than the predetermined threshold.

Solutions for evaluating source code generators use offline and online evaluation stages. Offline evaluation includes separating each of a plurality of input passages of software code into a plurality of constituent blocks. Each code generator (of a plurality of code generators) generates an equivalent block corresponding to each constituent block. A coding score is determined for each equivalent block (for each code generator), and the coding scores are aggregated across the equivalent blocks to provide an aggregate score for each code generator. A ranking of the aggregate scores is used to down-select to a fewer number of code generators for online evaluation. For this stage, the code generators output passages of software code, and user acceptance of the code generators' outputs may be used for further ranking and down-selection. Some examples weight the coding score according to a code utility estimate of the constituent blocks for which equivalent blocks are generated.

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 discloses a microwave photon BPSK direction modulation signal generation device and method. The device comprises a laser LD, a double parallel Mach-Zehnder modulator DPMZM, a 90-degree bridge, phase modulators PM1 and PM2, a light beam splitter OS, a light beam combiner OC and a photoelectric detector PD. A laser signal generated by the laser PD passes through the light beam splitter and then is input into the double parallel Mach-Zehnder modulator DPMZM and the phase modulator PM1 at equal power. A local oscillator LO signal of the upper branch is divided into two paths after passing through a 90-degree bridge; in the lower branch, a pseudo-random binary signal PRBS generated by an arbitrary waveform generator AWG is input into a phase modulator PM1 to generate a phase coded signal; and finally, after beam combination of the upper branch and the lower branch, beat frequency is carried out through a photoelectric detector PD, so that direction modulation signals carrying different phase information are obtained. Compared with a traditional BPSK directional modulation scheme, the scheme provided by the invention can independently realize directional modulation of a plurality of frequency bands, the frequency can reach 40GHz, and the bandwidth can reach 4GHz.

The present invention discloses a method for identifying the current characteristics of a transformer substation area based on the correlation peak decision method, including: collecting the synchronous phase information of the power grid, generating and injecting a unique phase-coded characteristic signal; collecting the current signal at the key nodes of the transformer substation area and extracting the phase information; constructing a dynamic adaptive phase relationship network to extract the feature vectors with topological invariance; performing correlation analysis on the extracted feature vectors and the standard template, and determining the identification result through adaptive correlation peak decision; dynamically adjusting the system parameters according to the identification result. The method of the present invention combines phase coding with topological invariant features, and has the characteristics of strong anti-interference ability, good environmental adaptability and high recognition accuracy.

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 discloses a complementary phase coding sequence signal processing method based on distance sidelobe shift and Doppler compensation, and relates to the technical field of radar signal processing, and the method comprises the steps: a radar transmitting signal employs a complementary coding sequence for phase modulation of a signal waveform; aD sampling, digital down-conversion and low-pass filtering are carried out on target echoes received by the radar, then the target echoes are rearranged into an echo signal matrix, and Doppler compensation is carried out on the echo signal matrix; and finally, pulse compression processing and moving target detection are performed on the compensated echo signal, target distance sidelobe moving is realized, and target distance-speed information is obtained. According to the complementary phase coding sequence signal processing method provided by the invention, the target distance sidelobe is effectively suppressed, the Doppler tolerance is improved, and an important technical support is provided for the complementary phase coding sequence signal in the field of low-altitude target detection.

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 multi-channel complementary phase coding frequency modulation waveform design method, device and system, and the method comprises the steps: taking the overall response level of minimizing an interference signal and the sidelobe level of a target signal as an optimization criterion under an anti-SMSP application background, and considering the mutual interference problem between different channels, establishing a multi-channel complementary phase coding frequency modulation waveform optimization model capable of resisting SMSP interference; solving a coding vector gradient of a target function about a coding vector in the optimization model; calculating a search direction by using the coding vector gradient, iteratively updating the waveform coding vector until convergence, and outputting the optimized waveform coding vector; and solving a corresponding multi-channel complementary phase coding frequency modulation waveform with SMSP interference resistance by using the optimized waveform coding vector. The method is suitable for a multi-channel radar system, and the accumulation of target energy and the cancellation of interference energy are realized by designing a plurality of complementary waveforms, so that the SMSP interference resistance of the waveforms is improved.

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.

Techniques are disclosed for transmitting and receiving multiple encoded information bits on a radar signal. In one aspect, a transmitter radar generates a first set of phase - decoded modulated symbols to convey multiple encoded information bits, generates a second set of phase - decoded modulated symbols as reference symbols with known phase modulation, phase - decodes a plurality of chirps of the radar signal based on the first set of phase - decoded modulated symbols and the second set of phase - decoded modulated symbols, and transmits the plurality of chirps based on the phase - decoding. A receiver radar determines a phase difference between the receiver and the transmitter radar based on the phases of the plurality of chirps, equalizes the phase based on the determined phase difference, determines a phase code of the first set of symbols based on the equalized phase, and decodes the encoded information bits based on the phase code of the first set of symbols.

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.