18 results about "Wideband radar" patented technology

The application relates to the field of ultra-wideband radar imaging and optical computing technology, in particular to a light computing real-time processing method for ultra-wideband radar imaging. The method comprises core steps of signal receiving and electro-optical modulation, optical pulse compression, initial phase compensation based on Kalman filtering, envelope alignment, coherence recovery and two-dimensional grid projection. Based on the ultrafast linear processing advantage and algorithm optimization principle of light computing, the application utilizes optical finite impulse response filters and adjustable delay line technology to disassemble and reconstruct the traditional imaging method, and reduces the end-to-end processing delay to the sub-millisecond level. The application breaks through the real-time processing bottleneck of ultra-wideband radar imaging, provides effective theoretical support and method basis for developing a full real-time ultra-wideband two-dimensional fine imaging system, and is widely applicable to application fields with high real-time requirements such as military reconnaissance and geological exploration.

This application proposes a method and device for enhancing the detection of static human targets. Based on the target echo model of radar penetration detection, the method uses adaptive frequency hopping technology to compare the energy difference between the actual detection data and the local echo template, and dynamically optimizes the transmission frequency band of radar detection. While reducing the coherent accumulation time, it significantly improves the signal-to-noise ratio of weak human life signals after medium penetration, and effectively enhances the detection performance of ultra-wideband radar for static human targets in medium penetration scenarios.

This utility model relates to an ultra-wideband radar sensor chip architecture, including a signal generator, a transmit link, and a receive link. The signal generator generates a first clock signal and a second clock signal. The first clock signal is output to the transmit link, and the second clock signal is output to the receive link. The transmit link includes a first pulse generator, a differentiator, and a transmit multiplexer with multiple transmit branch channels. The receive link includes a second pulse generator, a mixer, a receive multiplexer with multiple receive branch channels, a low-pass filter, an automatic gain control amplifier, and an analog-to-digital converter. This ultra-wideband radar sensor chip architecture adopts a multi-transmit, multi-receive approach, allowing each channel to operate independently in a time-division multiplexing manner, improving radar detection accuracy and resolution, and significantly expanding the application range of radar sensors.

This invention discloses a method for detecting respiratory signals using through-wall radar based on PCA and VMD. First, eigenvalue decomposition is performed on the ultra-wideband radar echo data matrix after removing the DC component. Then, mode decomposition is performed on the clutter-free dynamic signal matrix in the slow-time dimension. Relevant mode components within the respiratory frequency band are selected. The selected mode components are reconstructed. Fourier transform is performed in the slow-time dimension to construct a range-frequency spectrum. Finally, a two-dimensional Gaussian template conforming to the spectral characteristics of human respiration is constructed and matched. The range and frequency estimates of the human respiratory signal are calculated. This invention addresses the problems of weak anti-interference capability and high false alarm probability of single clutter suppression methods, thereby achieving accurate respiratory signal detection in strong clutter environments.

The application discloses a kind of based on gradient descent method's uniform array ultra-wideband radar positioning imaging method, it is related to radar positioning technical field, the signal matrix model after matching filtering is constructed in the application, matrix decomposition is carried out by gradient descent method, joint direction matrix and joint electromagnetic guide vector matrix are obtained, then, two groups of two-dimensional angle estimation values with high resolution and no ambiguity are respectively obtained from the two matrices, accurate angle parameters are obtained by weighted fusion, and target three-dimensional coordinates are calculated accordingly, finally, radar image is generated by back projection algorithm, so that the number of array elements and hardware complexity are significantly reduced, the inherent angle ambiguity problem of array is overcome, the multi-target angle resolution and parameter estimation stability are improved, and the calculation efficiency and engineering realizability are also considered.

A polarization conversion metasurface design method is used to realize wideband radar scattering cross section reduction. The feature is to design a polarization conversion metasurface unit first, each polarization conversion metasurface unit includes a bottom metal unit, an upper layer metal etching microstructure unit and a dielectric substrate unit; the configuration of different polarization conversion units is described by the difference of metal etching microstructure and the change of dielectric substrate thickness; the single polarization conversion metasurface unit is modeled, the scattering characteristics are calculated, the configuration optimization and parameter optimization of the metal etching microstructure and the dielectric substrate unit of the polarization conversion unit are carried out based on the genetic algorithm, and the optimal polarization conversion unit structure is obtained; the polarization conversion metasurface with periodic metal etching microstructure array is constructed, the polarization conversion metasurface capable of reducing scattering is designed, and the scattering characteristics are calculated. The mirror polarization conversion metasurface is used as the implementation form to realize the scattering reduction of the incident electromagnetic wave, which is conducive to the automatic design of the polarization conversion metasurface with special working frequency requirements.

This invention proposes a method for obtaining the broadband RCS of electrically large targets based on a communication base station. The implementation steps are as follows: 1) dividing the surface of the electrically large target into sections; 2) defining RWG basis functions on the triangular facets; 3) initializing parameters; 4) calculating the Chebyshev frequency sampling points within the frequency band f based on CAT; 5) calculating the surface current at each Chebyshev frequency sampling point using the equivalent dipole moment method and the method of moments; 6) calculating the wavenumber k at each frequency point within the band. a Surface current; 7) Obtain the radar cross section (RCS) of electrically large targets. Based on the Chebyshev approximation method (CAT), this invention combines the equivalent dipole moment method to significantly reduce the calculation time of the impedance matrix and improve the calculation efficiency of the broadband radar cross section of electrically large targets.

The application relates to a target amplitude flicker loss scene-oriented ultra-wideband radar range image enhancement method and relates to the technical field of radar signal processing.The method comprises the following steps: detecting a detection target in a detection scene by using a step frequency ultra-wideband radar, and acquiring frequency domain echo data corresponding to the detection target; based on an iterative unfolding reconstruction network, an imaging target function corresponding to the frequency domain echo data is solved iteratively, and a coarse reconstruction range image corresponding to the detection target is acquired; finally, the coarse reconstruction range image is compensated and enhanced by using an enhancement network, and an enhanced range image corresponding to the detection target is generated; the enhancement network is used for compensating the track cavity of the detection target, and suppressing the sidelobe uplift of the detection target and the residual static clutter of the detection scene under the condition that the amplitude of the detection target flickers and sampling is lost.The application can realize high-quality high-resolution range image reconstruction and enhancement, and provide a stable and high-fidelity range image input for subsequent imaging and positioning and the like.

The application discloses a kind of space-time adaptive processing methods of airborne broadband radar based on frequency domain compensation, comprising: obtaining target echo signal;The distance sampling is carried out to broadband echo signal, and the sampled target echo signal is obtained;The Fourier transform is carried out to the sampled target echo signal, and the target echo signal in distance frequency domain is obtained;The target echo signal after matching filtering is obtained by carrying out matching filtering processing to the target echo signal in distance frequency domain;According to the preset phase compensation factor, the envelope movement between each array element and each pulse of the target echo signal after matching filtering is compensated, and the compensated target echo signal is obtained;The inverse Fourier transform is carried out to the compensated target echo signal, and the target echo signal in distance time domain is obtained;The echo signal in distance time domain is carried out space-time adaptive processing, and clutter and noise are inhibited.The application can improve effect more obvious.

This invention discloses an optimized method for deception jamming of frequency-hopping radar based on a four-dimensional antenna array. This method addresses the problem of existing four-dimensional antenna arrays failing to jam against broadband radars with rapidly changing frequencies due to beam squint effects. It constructs a broadband array pattern model with the entire radar frequency hopping point set as variables and establishes a hierarchical optimization cost function. This function prioritizes suppressing the echo from the true target direction to below a safe threshold across the entire frequency band, and then maximizes the minimum gain in the direction of the false target. A differential evolution algorithm is used to globally optimize the RF switching timing parameters of each array element, obtaining a set of frequency-independent robust optimal timing sequences. Loading these timing sequences into the controller enables the four-dimensional antenna array to stably achieve deception jamming effects that conceal the true target and enhance the false target across the entire frequency hopping bandwidth of the radar without real-time adjustments. This effectively overcomes the aperture crossing effect and ensures the robustness of jamming when the enemy radar frequency changes.

This invention discloses a method for post-disaster life detection and location in coal mines based on ultra-wideband radar, belonging to the field of radar engineering and signal processing technology. It is used for post-disaster life detection and location in coal mines, including: collecting echo signals from explosion-proof UWB radar at different preset measurement points; performing time-domain multiple differential averaging enhancement on the echo matrix of each measurement point; conducting FFT spectrum analysis on the enhanced signal; extracting candidate breathing frequencies through dynamic thresholding; confirming valid life forms and their breathing frequencies through multi-measurement point cross-verification; constructing a reference signal using the confirmed breathing frequencies; extracting the life form echo travel time by calculating the Pearson correlation coefficient; and combining the measurement point coordinates and electromagnetic wave velocity to calculate the precise three-dimensional coordinates of the life form using a time-difference positioning algorithm. This invention achieves direct enhancement of weak life signals through a time-domain multiple differential averaging algorithm, exhibiting significantly higher robustness and reliability in extreme rescue scenarios with scarce data and unknown interference patterns.

This invention belongs to the field of UWB wireless positioning technology, specifically providing an ultra-wideband radar three-dimensional positioning method. First, a transceiver antenna array is constructed, with elements arranged in an N×N square array, where N is an odd number ≥ 3. A transceiver antenna is placed at the center of the array, and receiving antennas are placed on the other elements. Based on the transceiver antenna at the center of the array, the arrival time of the target echo signal is collected, starting from the feeding moment, and the transmit / receive time difference is calculated. Then, based on any three receiving antennas located at the four corners of the transceiver antenna array, the arrival time of the target echo signal is collected, and the relative time difference between the three receiving antennas is calculated. Based on the transmit / receive time difference and the relative time difference, the target position coordinates are calculated using a three-dimensional positioning model. In summary, this invention constructs a three-dimensional positioning mathematical model based on the radiation characteristics of an electromagnetic time domain (TEM) antenna array. This model can significantly reduce computational complexity while ensuring positioning accuracy.

This invention discloses a broadband radar target energy accumulation method based on a combined transmit and receive design. First, by acquiring the radar transmitted signal and the corresponding design requirements of the mismatch filter, an objective function for a broadband radar waveform optimization problem is designed. Then, a broadband radar waveform constraint model and an optimization problem model are established. Finally, the MM algorithm is used to solve the optimization problem and output the optimization result. This method accumulates the energy of a range-extended target exhibiting multiple scattering point characteristics into a single envelope, improving the signal-to-noise ratio of the processed range-extended target. The designed signal is a phase-coded signal; its phase agility, compared to the continuous phase of a linear frequency modulated signal, more effectively improves the signal's anti-sorting capability, while ensuring low intercept performance of the radar transmitted signal while maintaining target detection capability.

This invention belongs to the field of radar technology, specifically relating to a method for broadband MIMO radar beamforming in a spectrum-dense environment. The method includes: Step 1: constructing an optimization model; Step 2: manifold transformation and penalty function construction; Step 3: solving using a simplified quasi-Newton method; Step 4: adaptively updating the penalty factor to improve the optimization process for broadband MIMO radar beamforming in a spectrum-dense environment, providing a final manifold-based accurate penalty method. The method first constructs a CCM that satisfies the CMC, and reformulates the SSNC as an accurate penalty function, thus transforming the problem into an unconstrained optimization problem on the CCM; subsequently, a simplified quasi-Newton method is developed to optimize the problem on the CCM; finally, the penalty factor is adaptively updated to improve the optimization process.

This invention relates to a method and system for denoising and reconstructing vital signs signals from ultra-wideband radar. The method includes: S1, preprocessing the baseband signal of the vital signs echo to obtain a mixed signal of vital signs to be decomposed; S2, globally adaptively optimizing the core parameters of the ICEEMDAN algorithm based on DBO to obtain the optimal parameter combination; S3, substituting the optimal parameter combination into the ICEEMDAN algorithm to adaptively decompose the mixed signal of vital signs to be decomposed, obtaining multiple IMF components; S4, selecting effective components of the IMF components based on the frequency band characteristics of human physiological signals and Pearson correlation analysis; S5, adaptively weighted fusing and reconstructing the effective IMF components of respiration and heartbeat respectively, outputting respiratory vital signs signals and heartbeat vital signs signals. Combining the DBO algorithm with the ICEEMDAN algorithm significantly improves the algorithm's scene adaptability and decomposition stability.

This invention provides a method, system, electronic device, medium, and product for state perception of rotating machinery based on the micro-Doppler dynamic structure of ultra-wideband radar, relating to the field of rotating machinery condition monitoring technology. The method includes: acquiring echo sequences of a rotating machinery target area collected by an ultra-wideband radar; filtering target range gates or target range gate groups to construct corresponding slow-time echo sequences; sequentially performing background suppression, phase stabilization, and micro-Doppler dynamic structure construction on the slow-time echo sequences to obtain a micro-Doppler dynamic structure representation; extracting explicit dynamic structure features based on the micro-Doppler dynamic structure representation, and / or constructing implicit representations; and obtaining the state perception result of the rotating machinery based on the dynamic structure features and / or the implicit representations. This invention overcomes the limitation of non-contact monitoring relying on a single feature and improves the robustness of state perception under complex operating conditions.

This invention discloses a Nyquist folding reception method and system based on a broadband optical comb. The method includes generating equally spaced optical local oscillators with doubled bandwidth in the optical domain using a continuous wave light source and cascaded intensity modulators and dual-phase modulators. The cascaded modulators are simultaneously driven by a baseband SFM signal, and the modulation index and DC bias are jointly adjusted to achieve effective broadening and balanced distribution of the high-order spectrum. After the target RF signal and the optical local oscillator are mixed in the optical domain, the high-frequency RF signal is folded into the low sampling rate observation band by photoelectric detection and low-pass filtering. The time-frequency characteristics of the folded signal are used to determine the Nyquist zone index and reconstruct the signal. This invention does not require high-speed position modulation optical pulses, has a compact system structure, and is simple to implement. It achieves real-time reception of ultra-wideband RF signals under low-speed sampling conditions and is suitable for applications such as broadband radar, wireless communication, and cognitive wireless.

The application discloses a kind of based on wideband radar unmanned aerial vehicle cluster extended target detection tracking method and system, specifically is: first set unmanned aerial vehicle cluster scene, calculate target electromagnetic scattering characteristics, unmanned aerial vehicle cluster is equivalent to by multiple scattering center Extended target is generated cluster extended target wideband radar echo;Then calibration and compensation are carried out to wideband observation data, if there is no candidate target, then wait for the data input of next frame;When target distance information is extracted on distance dimension, angle estimation is carried out using multi-beam coherent fitting method, and the distance-angle detection result of cluster target is output;Finally, based on joint information, data association is carried out, the spatial shape parameter of cluster target is introduced into tracking model as state quantity, and target motion state is predicted and updated together, dynamic regulation of candidate observation range is realized.The application has high calculation efficiency, model is simple, and the tracking precision and stability of dynamic unmanned aerial vehicle cluster target detection and tracking are improved.