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33 results about "Instantaneous bandwidth" patented technology

Instantaneous bandwidth is a statistical measure of the seismic wavelet, but it relates to various physical conditions: Represents seismic data bandwidth sample by sample. It is one of the high-resolution character correlators. Shows overall effects of absorption and seismic character changes.

Broadband receiver ADC nonlinear spurious suppression method and device

The invention discloses a broadband receiver ADC nonlinear spurious suppression method and device, and relates to the technical field of instruments and meters, and the method comprises the following steps: receiving an intermediate frequency signal, carrying out the analog-to-digital conversion of the intermediate frequency signal, and obtaining a digital intermediate frequency signal, the intermediate frequency signal being obtained through the receiving of a superheterodyne architecture; the method comprises the following steps: reducing the signal bandwidth of a digital intermediate frequency signal by using a CIC extraction mode to obtain different signal bandwidths BW, and performing spectral analysis on the different signal bandwidths BW by using a fixed-point FFT to obtain corresponding resolution bandwidths RBW; on the premise that the cost of the receiver is not increased, spurious signals under the narrow-band instantaneous bandwidth are reduced, and the index of the receiver is improved.
Owner:ANHUI EGRETS ELECTRONICS TECH

Modulation identification method and device based on microwave photon frequency-time mapping

The invention discloses a modulation identification method based on microwave photon frequency-time mapping. The method comprises the following steps: firstly, performing microwave photon frequency-time mapping on a to-be-measured microwave signal, and mapping frequency information of the to-be-measured microwave signal to a time domain to obtain a time-frequency characteristic of the to-be-measured microwave signal; and inputting the time-frequency characteristics of the to-be-detected microwave signal into a pre-trained neural network model so as to identify the modulation form of the to-be-detected microwave signal. The invention also discloses a modulation identification device based on microwave photon frequency-time mapping. Compared with the prior art, on the basis of a microwave photon frequency-time mapping model, Fourier transform is directly completed through an optical device, a radio frequency signal is modulated to be processed in an optical domain, time delay characteristics of dispersion broadening and compression are combined, the picosecond-level time stretching precision is achieved, the instantaneous bandwidth limitation of a traditional spectrum analyzer is broken through, and the spectrum analysis precision is improved. Frequency spectrum processing of large-bandwidth signals can be completed in real time, computing resources are saved, and the real-time performance of modulation identification is improved.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Channel simulation system capable of being flexibly established and expanded

The invention discloses a channel simulation system capable of being flexibly established and expanded, and relates to the technical field of signal receiving, transmitting and processing. The system comprises a multi-element expansion interconnection calculation matrix, and calculation arrays with different topological structures and different scales can be constructed through connection relations between upper and lower expansion interconnection calculation matrix hierarchies, between expansion interconnection calculation matrixes and interconnection calculation matrixes and between internal calculation units of the interconnection calculation matrixes. The larger the number of array elements of the interconnection calculation matrix is, the larger the number of layers of the expansion interconnection is, the larger the scale of the calculation matrix is, the larger the total computing power and the larger the storage space are, the larger-scale channel simulation requirement can be met, and the target of adapting to different channel scales and instantaneous bandwidths is achieved. Therefore, a user can easily customize the channel simulation system according to own requirements, product functions and channel scales can be gradually expanded through staged construction, the cost is reduced, and the product utilization rate is improved.
Owner:CHENGDU LISIFANG INFORMATION TECH CO LTD

2-18G transceiver module with 2G instantaneous bandwidth

The invention discloses a 2-18G transceiver module with a 2G instantaneous bandwidth, and relates to the field of signal processing, and the 2-18G transceiver module with the 2G instantaneous bandwidth comprises a down-conversion link which is used for receiving an input 2-18GHz signal, converting the input 2-18GHz signal into a 0.4-2.4 GHz signal after the input 2-18GHz signal is mixed by a frequency hopping local oscillator signal 24-40GHz and a fixed local oscillator signal 20.6 GHz in sequence, and outputting the 0.4-2.4 GHz signal to a baseband processing unit; the local oscillation generation link is used for generating a frequency hopping local oscillation signal 24-40GHz and a fixed local oscillation signal 20.6 GHz and assisting the down-conversion link and the up-conversion link to work; compared with the prior art, the invention has the following beneficial effects: AD sampling can reach an instantaneous bandwidth of 2GHz by changing a frequency conversion mode; a link is made into a single module, and a VPX connector is used, thereby facilitating the overall plugging, enabling the whole system to be modularized, and improving the integration level.
Owner:WUXI SIEN ELECTRONIC TECH CO LTD

Bistatic radar system based on superheterodyne Rydberg atom receiver

The invention provides a bistatic radar system based on a superheterodyne Rydberg atom receiver. The transmitting end and the receiving end of the system are different in position and are synchronized by a timing system device. A system transmitting end transmits a linear frequency modulation signal, and a system receiving end uses a Rydberg atom receiver to receive an echo of a detection signal reflected by a target. The Rydberg atom receiver is of a superheterodyne structure, that is, a receiving end firstly generates a linear frequency modulation signal consistent with a transmitting end based on a timing system device, then inputs the linear frequency modulation signal and a received echo signal into an atom gas chamber together, then measures the spectral change of probe light penetrating through the atom gas chamber, and realizes target detection mainly according to the measured spectral change. And distance measurement and positioning. The system can utilize the advantages of high sensitivity, small size and the like of the Rydberg atom receiver, and overcomes the defect of insufficient instantaneous bandwidth of the atom receiver through special design.
Owner:Chinese People's Liberation Army Cyberspace Force Information Engineering University

A 2GHz Instantaneous Bandwidth Radar Target Echo Simulation System

A 2GHz instantaneous bandwidth radar target echo simulation system, relating to the technical field of radar target echo simulation systems, comprises a radio frequency downconversion module, an analog-to-digital converter, a field programmable gate array, a digital-to-analog converter, and a radio frequency upconversion module. Utilizing a high sampling frequency AD and 16-channel multiphase operation, the FPGA sampling frequency is 375MHz. Combining 16 channels of signals yields a total sampling rate of 6GHz, increasing the instantaneous bandwidth to 2GHz. This system combines high instantaneous bandwidth, high resolution, multiple scattering points, and integration.
Owner:BEIJING INST OF RADIO METROLOGY & MEASUREMENT

Range-velocity two-dimensional super-resolution method for radar swarm targets in strong ground clutter environment

The present invention belongs to the technical field of radar detection and tracking of swarm UAV targets, and specifically relates to a two-dimensional super-resolution method for distance and speed of radar swarm targets in a strong ground clutter environment, which suppresses emission leakage and ground clutter by fast time dimension bandpass filtering and slow time dimension MTI filtering, expands the number of samples by sliding rearrangement of radar echoes, and finally obtains a two-dimensional super-resolution capability of distance and speed that breaks through the Rayleigh limit by a super-resolution digital signal processing method. The present invention can perform clutter suppression and two-dimensional super-resolution processing of distance and speed on LFMCW radar swarm UAV target echoes under a strong ground clutter background, thereby obtaining a two-dimensional super-resolution capability of distance and speed that breaks through the Rayleigh limit under the condition that the radar instantaneous bandwidth resources and accumulation time resources are limited.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION

Multi-dimensional domain signal measuring device based on stimulated Brillouin scattering effect

The invention discloses a multi-dimensional domain signal measuring device based on a stimulated Brillouin scattering effect, and the device simulates the arrival angle information of a signal through the phase modulation introduced by an optical phase shifter, and maps the space information of a to-be-measured signal through the difference of the beat frequency power of different arrival angles. A stimulated Brillouin scattering effect (SBS) is utilized to perform frequency selection on a chirp optical pulse sequence (COPS) to obtain frequency and time information of a signal to be measured, and energy information of the signal to be measured is obtained by utilizing the difference of modulation depths of the modulator by the signals to be measured with different energies. By performing multi-dimensional mapping on space, frequency, time and energy dimension information, high-precision measurement on multi-dimensional domain signals of the to-be-measured signals can be realized at the same time. The method has the advantages of high measurement speed, high precision, large instantaneous bandwidth and the like, and can be widely applied to the fields of radar signal detection, electronic countermeasure, microwave communication and the like.
Owner:DALIAN UNIV OF TECH

Frequency domain-time frequency domain adaptive time-varying filtering method with human-computer interaction characteristic

The invention discloses a frequency domain-time frequency domain adaptive time-varying filtering method with human-computer interaction characteristics, which comprises the following steps: manually selecting reference data points according to the energy distribution of signals in a time frequency domain, and obtaining an instantaneous frequency curve of a component to be extracted through cubic spline interpolation fitting; based on the short-time Fourier transform energy matrix and the cumulative distribution function, the instantaneous transmission band width at each moment is calculated in a self-adaptive mode; taking the instantaneous frequency as a center frequency and the instantaneous bandwidth as a transmission band boundary, constructing an elliptical digital band-pass filter bank, and forming a self-adaptive time-varying filter; performing time-frequency domain filtering decomposition on the original signal, and performing inverse short-time Fourier transform reconstruction to obtain a pure component signal; order spectrum / envelope order spectrum analysis is carried out on the components, and gear fault features are extracted. The method gives consideration to time domain and frequency domain information, achieves one-time filtering decomposition, is high in calculation efficiency, is high in anti-noise performance, and is suitable for the fault diagnosis of equipment with complex non-stationary signal features.
Owner:CHANGSHA UNIVERSITY OF SCIENCE AND TECHNOLOGY

Broadband frequency hopping device based on high orbital angular momentum Rydberg atoms

The invention provides a broadband frequency hopping device based on high-orbital angular momentum Rydberg atoms. An atomic air chamber comprises the high-orbital angular momentum Rydberg atoms; the first reflecting mirror and the second reflecting mirror are respectively used for reflecting the detection light and the coupling light to the atom gas chamber so as to excite high-orbital angular momentum Rydberg atoms from a ground state to an excited state and pump the high-orbital angular momentum Rydberg atoms to a first Rydberg state; the first microwave generator, the second microwave generator and the third microwave generator are used for enabling high-orbital angular momentum Rydberg atoms to be transited to a second Rydberg state, a third Rydberg state and a fourth Rydberg state respectively; and the photoelectric detector is used for receiving the detection light passing through the atomic gas chamber. According to the invention, frequency hopping crossing 6 octaves can be realized, the frequency hopping speed is 60khops / s, and the frequency hopping point number is expanded under the limited instantaneous bandwidth by using the microwave frequency comb. The method has potential application value in the field of secret radio communication.
Owner:SHANXI UNIV

Software-defined radar full-link integrated signal processing method

The invention discloses a software-defined radar full-link integrated signal processing method, and belongs to the technical field of radar signal processing. According to the method, a hierarchical decoupling universal hardware platform composed of an AD9361 universal radio frequency front end, a high-speed data transmission interface and an FPGA + GPU + CPU heterogeneous computing rear end is constructed, and software definition of full-link functions such as waveform generation, signal processing and synchronous control is achieved. According to the invention, a dual adaptive CFAR detection algorithm of distance dynamic window + clutter multi-algorithm switching is adopted, so that all clutter environments can be adapted; nanosecond coherent synchronization of multiple radar nodes is realized through a GPS taming clock, and UTC synchronization precision can reach + / -50ns; and multi-station MIMO cooperative detection is realized through software-based beam forming. According to the invention, the instantaneous bandwidth of the radar is improved from 5MHz to 56MHz, the signal processing delay is reduced from 6.8 microseconds to 1.2 microseconds, the false alarm rate is reduced from 10 to 10, the research and development period is shortened from 18-24 months to 6-12 months, and the hardware cost is reduced to 1 / 5-1 / 10 of that of a traditional scheme.
Owner:何祥宇 +1

Multi-pattern interference signal optical generation method for synthetic aperture radar

The invention discloses a multi-pattern interference signal optical generation method for a synthetic aperture radar, and relates to the technical field of optical communication, the technical field of microwaves and the technical field of electronic countermeasures. The method is shown in a figure 1 in the specification, and comprises a laser LD, a dual-parallel Mach-Zehnder modulator DP-MZM and a photoelectric detector PD. Carrier suppression double-sideband modulation of intercepted radar signals is realized through the MZM2 of the lower arm of the DP-MZM, different phase modulation is performed on each echo through the main modulator, azimuth cosine phase modulation is realized, and two-dimensional cosine phase modulation interference signals can be generated after the radar signals and MZM1 modulated cosine signals of the upper arm of the DP-MZM pass through the photoelectric detector. The device is simple in structure and good in interference real-time performance, overcomes the electronic bottleneck, can generate radar interference signals with wide frequency bands and large instantaneous bandwidth, realizes deception and suppression interference, and adapts to the requirements and development trend of radar electronic warfare.
Owner:XIDIAN UNIV

Satellite-borne SAR signal real-time rapid measurement system

The invention discloses a satellite-borne SAR (synthetic aperture radar) signal real-time rapid measurement system, which is used for solving the problems that the measurement speed is not high enough, the system bandwidth is not wide enough and high-speed mass data cannot be continuously recorded in real time when an existing electronic reconnaissance receiver technology is used for reconnaissance of a satellite-borne SAR signal. The device has the functions of collecting data of satellite-borne SAR signals with the bandwidth of 4 GHz and measuring parameters in real time, accurate parameters of the broadband SAR signals are calculated in real time, and PDW and EDW are formed; the ultra-wideband ultra-wideband filter has the characteristics of wide working frequency and large instantaneous bandwidth, the working frequency range is 1-18GHz, and the maximum instantaneous bandwidth is 4GHz; the system has a real-time rapid measurement function, the response time is 100 us, the operation speed is high, and the measurement result can guide other confrontation equipment in real time; the method supports three signal searching and tracking conditions of guiding, automatic and manual operation, and an operator can flexibly set according to whether the signal type, the information data and the reconnaissance environment are known or not.
Owner:BEIJING INST OF TECH

Microwave photon interference scheme with self-interference elimination function for synthetic aperture radar

The invention discloses a microwave photon interference scheme with a self-interference elimination function for a synthetic aperture radar. The invention relates to the technical field of radars and the technical field of microwaves, and is mainly applied to microwave photon interference signal generation and self-interference cancellation. The method is shown in an attached drawing, and comprises a laser device LD, a double-parallel dual-drive Mach-Zehnder modulator DP-DDMZM, an electric delay line DL, an electric attenuator ATT and a photoelectric detector PD. A sub-modulator DDMZM1 of a dual-parallel dual-drive Mach-Zehnder modulator DP-DDMZM is used for eliminating a self-interference signal, and a periodic rectangular pulse signal input to a lower radio frequency port of a sub-modulator DDMZM2 is used for realizing periodic change of an optical carrier amplitude. Periodic change of an optical carrier phase is realized through a periodic rectangular pulse signal input to a bias voltage port of the main modulator MZM, and finally photoelectric conversion of an optical signal output by the DP-DDMZM is completed through the photoelectric detector PD, so that flexible and effective two-dimensional interference and elimination of a self-interference signal on a distance domain and an azimuth domain can be realized at the same time. The two-dimensional interference signal generation and self-interference cancellation functions are integrated, parameter tuning is flexible, the structure is simple, the real-time performance is good, the generated interference signal is high in frequency band, the instantaneous bandwidth is large, the working range is wide, and the radar electronic warfare requirement and development trend at present are met.
Owner:XIDIAN UNIV

Instantaneous microwave frequency measurement method and system based on double electro-optic comb vernier measurement method

The application discloses a kind of instantaneous microwave frequency measurement method and system based on double electro-optical comb vernier measurement method, laser emitted by light source is used for intensity modulation with detection microwave respectively, local light comb with small repetition frequency difference is generated, and after detection light comb, the signal after intensity modulation is respectively frequency modulated with local light comb after radio frequency and radio frequency after detection light comb, based on vernier effect, the position of comb tooth close to the frequency of microwave to be measured is determined according to the difference of the difference of two frequency differences, and microwave frequency is accurately positioned in the left, right or middle of local light comb and detection light comb comb tooth position, and then microwave signal frequency is obtained.The application has wide frequency coverage, large instantaneous bandwidth, high measurement accuracy, fast measurement speed, and can realize simultaneous measurement of multiple microwave frequencies, with low system complexity and low system cost.
Owner:SHANGHAI JIAOTONG UNIV

A signal processing method suitable for various signal characteristics

This invention discloses a signal processing method applicable to various signal characteristics, relating to the fields of communication and radar signal processing technology. By combining the construction of a multi-dimensional signal feature library with real-time spectrum sensing, this invention achieves rapid analysis and accurate characterization of deep-space radar signal characteristics. The feature library is generated based on unsupervised clustering of historical data, covering various signal templates such as transient impulses, periodic coherence, and steady-state noise. It not only provides rich prior knowledge references but also supports online sliding window incremental updates, ensuring that feature representation always conforms to actual environmental changes. The real-time spectrum sensing employs adaptive window time-frequency analysis, with the window length dynamically adjusted according to the signal's instantaneous bandwidth and local stationarity, effectively balancing the contradiction between frequency resolution and time resolution and overcoming the limitations of traditional fixed-window analysis in non-stationary scenarios.
Owner:BEIJING KAIYUN SPACE TECHNOLOGY CO LTD

A method and system for aligning the electrical and mechanical axes of a large broadband phased array antenna.

The application discloses a large wideband phased array antenna electric axis and mechanical axis alignment method and system, and belongs to the technical field of phased array antennas. The method comprises the following steps: in the frequency slicing stage, the working frequency of the phased array antenna is equally divided into n slicing frequency points in the instantaneous bandwidth range; in the beam scanning and data acquisition stage, the amplitude data set of each slicing frequency point is collected; in the electric axis position extraction stage, the electric axis position is extracted from the amplitude data set of each slicing frequency point, and an electric axis position set is obtained; in the electric axis center calculation stage, the least square method is used to find the regional electric axis position set, which is used as the electric axis center position of the phased array antenna in the instantaneous bandwidth; and in the electric axis and mechanical axis alignment stage, the beam scanning instruction is set according to the electric axis center position, so that the electric axis and the mechanical axis of the phased array antenna are aligned. The application is not affected by the precision of artificial mechanical adjustment, and can achieve the alignment precision of the electric axis and the mechanical axis at the level of 0.01 degrees.
Owner:CHENGDU TOPANTECH CO LTD

Method and system for aligning electric axis and mechanical axis of large-scale broadband phased-array antenna

The invention discloses a large-scale broadband phased-array antenna electric axis and mechanical axis alignment method and system, and belongs to the technical field of phased-array antennas. The method comprises the following steps: a frequency slicing stage: equally dividing the working frequency of the phased-array antenna into n slice frequency points within an instantaneous bandwidth range; in a beam scanning and data acquisition stage, acquiring an amplitude data set of each slice frequency point; an electric axis position extraction stage: respectively extracting an electric axis position from the amplitude data set of each slice frequency point to obtain an electric axis position set; in the electric axis center calculation stage, a least square method is adopted to find out an electric axis position concentration area, and the area serves as the electric axis center position of the phased-array antenna in the instantaneous bandwidth; and an electric axis and mechanical axis alignment stage: setting a beam scanning instruction according to the central position of the electric axis, so that the electric axis of the phased-array antenna is aligned with the mechanical axis. The method is not limited by the influence of manual and mechanical adjustment precision, and the electric shaft and mechanical shaft alignment precision at the 0.01 degree level can be achieved.
Owner:CHENGDU TOPANTECH CO LTD

Reconfigurable dynamic bandwidth allocation method and system

The invention discloses a reconfigurable dynamic bandwidth allocation method and system, and the method comprises the steps: S1, setting a statistical mechanism in a bandwidth detection engine, carrying out the statistics of the instantaneous bandwidth and the average bandwidth of each channel, carrying out the normalization processing of the statistical results of the instantaneous bandwidth and the average bandwidth, and transmitting the statistical results of the instantaneous bandwidth and the average bandwidth to a bandwidth analysis engine in real time; s2, after statistical data of the instantaneous bandwidth and the average bandwidth are received, a bandwidth analysis engine carries out comparative analysis on the instantaneous bandwidth and the average bandwidth which are counted in real time by each channel, and carries out arrangement of the priority of each channel according to a Round-Robin scheduling logic algorithm strategy; s3, the bandwidth analysis engine sends an analysis result to a strategy updating engine, the strategy updating engine collects and stores data of each channel, and a set of parameters {type [i], level [i], rank [i] and scale [i]} is set for each channel in the strategy updating engine; and S4, the bandwidth allocation engine receives the allocation strategy from the strategy updating engine, and directly performs dynamic bandwidth allocation on each path according to setting of parameters {type [i], level [i], rank [i] and scale [i]}.
Owner:SUZHOU RICORE IC TECH LTD

A frequency hopping signal processing method and system based on binary classification

The present invention relates to the field of signal processing technology, and discloses a method for processing a frequency hopping signal based on binary clustering, which uses an adaptive threshold binary clustering algorithm to separate the signal data and noise data of the frequency hopping signal, thereby performing denoising on the frequency hopping signal. The present invention solves the problems of the prior art that the instantaneous bandwidth of the frequency hopping signal cannot be estimated and the parameter estimation accuracy is low.
Owner:NO 30 INST OF CHINA ELECTRONIC TECH GRP CORP

A method for increasing the instantaneous bandwidth of a throwable active decoy bomb

A method for increasing the instantaneous bandwidth of a throwable active decoy belongs to the technical field of interference of an external throwable active decoy in electronic countermeasures. A receiving end divides an 8GHz bandwidth signal into two 4GHz bandwidth radio frequency signals, mixes the two 4GHz bandwidth radio frequency signals into the same 4GHz bandwidth intermediate frequency signal, and folds the 8GHz bandwidth radio frequency signal into a 4GHz bandwidth intermediate frequency signal by combining, and the signal amplitudes in the two intermediate frequency signals are superimposed; a transmitting channel divides a 4GHz bandwidth intermediate frequency signal into two, mixes the two 4GHz bandwidth intermediate frequency signals into two signals of f0~f0+4GHz and f0~f0‑4GHz, respectively, and combines and superimposes the two 4GHz bandwidth radio frequency signals to form an 8GHz instantaneous bandwidth signal. The present invention uses an ADC with a sampling rate of 9Gsps to achieve an instantaneous bandwidth of 8GHz, which solves the problem of achieving an instantaneous large bandwidth in a small space of a decoy.
Owner:SHENYANG HANGSHENG TECH CO LTD

Multi-modal data fusion spot electricity price prediction method

The invention discloses a spot electricity price prediction method based on multi-modal data fusion, particularly relates to the field of electricity price prediction, and is used for solving the problems of error accumulation amplification and prediction precision distortion caused by high-frequency noise in multi-modal data fusion. Direct interference of noise on subsequent processes is avoided; extracting and dynamically revising confidence information to ensure that the reliability of different components is accurately evaluated; secondly, a high-confidence part is processed preferentially in the fusion stage, and a low-confidence part is smoothed, so that a core trend is reserved, and fluctuation deviation is reduced at the same time; and finally, iteratively correcting the deviation by using the load reference until the convergence and outputting a prediction curve. The front-end division provides pure input, the middle-section revision and fusion interaction optimization weight, and the rear-end correction refines the result through feedback circulation, so that high-frequency noise is effectively suppressed in new energy electricity price prediction, market dynamic changes are captured, and the accuracy and stability of a prediction curve are improved.
Owner:NANJING AOXINGUANG INTELLIGENT IND DEVELOPMENT CO LTD

Optically assisted ultramulti octave ultra wideband synthetic aperture radar system

The application relates to a light-assisted super-octave ultra-wideband synthetic aperture radar system and belongs to the technical field of ultra-wideband synthetic aperture radar, solves the problem of the limitation of the instantaneous bandwidth of a traditional electronic system, and is characterized in that the system comprises a digital system, an intermediate frequency system and a radio frequency system, and is further characterized in that the system further comprises a photonic radio frequency front end; the photonic radio frequency front end is connected between the intermediate frequency system and the radio frequency system; a photonic-assisted frequency multiplication technology is adopted to multiply the input intermediate frequency LFM signal and mix the multiplied signal with a local oscillation signal to generate a super-octave ultra-wideband signal; a photonic-assisted dechirp technology is adopted to multiply a received echo signal reflected by a target scene with a reference signal to generate a dechirped target echo signal; the reference signal is a linearly amplified and spurious-free ultra-wideband signal of the super-octave ultra-wideband signal. The application breaks through the limitation of the instantaneous bandwidth of the traditional electronic system and provides a new technical means for a large-instantaneous-bandwidth SAR system.
Owner:AEROSPACE INFORMATION RES INST CAS

FPGA-Based General Ultra-Wideband Calibration Direction Finding Method and System

The present invention discloses a general ultra-wideband calibration and direction-finding system and method based on FPGA. The PDW information is processed within the FPGA. Through the phase comparison technology, the inherent phase error introduced by channel inconsistency is eliminated. Calibration is performed at fixed frequency points, and smoothing and interpolation processing are carried out. The data of multiple calibration analyses are averaged to improve the accuracy of calibration. Based on a single-bit receiver, the present invention adopts the phase comparison calibration and direction-finding technology, which has high sensitivity, an ultra-wide instantaneous bandwidth, and achieves high direction-finding accuracy with a relatively small amount of equipment.
Owner:THE 723RD RES INST OF CHINA SHIPBUILDING IND CORP

A multi-channel ultra-wideband under-sampling instantaneous frequency measurement method

The application relates to a multi-channel ultra-wideband undersampling instantaneous frequency measurement method, belonging to the technical field of wideband digital radars, and solving the problem of spectrum overlap of multiple signals; for a scheme of multiple channels with different time delays, phase frequency measurement is combined with the remainder theorem to demodulate the frequency of an input signal; for signals near f s / 2, phase frequency measurement is carried out through the time delay difference between different channels to solve the frequency band in a targeted manner; for signals near f s / 2, multi-rate sampling is realized through a time-sharing sampling method, threshold discrimination and parameter matching are carried out on the FFT frequency measurement result through the remainder theorem, and finally, the PDW signal is demodulated, the method does not need to provide a high-speed pseudo-random sequence, has hardware realizability, has the characteristics of small size, no need of channelization, low algorithm implementation complexity, strong robustness and strong demodulation capability compared with the prior art, and can realize high-precision undersampling frequency estimation of radar signals under the index of 0 to 18G instantaneous bandwidth.
Owner:CHINA ELECTRONIC TECH GRP CORP NO 38 RES INST

Multi-model irregular wave height prediction method and system based on physical knowledge constraint and dynamic attention fusion

This application provides a multi-model irregular wave height prediction method and system based on physical knowledge constraints and dynamic attention fusion. The prediction system includes a prediction unit and a training unit. The prediction unit includes a first prediction model that outputs a first wave height prediction result based on the instantaneous bandwidth sequence of wave height from multiple wave height segments in a historical wave height sequence; a second prediction model that outputs a second wave height prediction result based on the instantaneous bandwidth sequence of wave height corresponding to a backward reconstruction sequence of the historical wave height sequence at multiple time scales; a regression coefficient model for generating a dynamic regression coefficient combination; a combined output module for weighted combination and outputting the final wave height prediction result; and a training unit that trains the prediction unit using a total loss function that includes a conventional loss term and a physical knowledge constraint loss term. The technical solution of this application improves the prediction effect of wave height under extreme sea states by weighting multiple prediction models with frequency band information and subjecting the training process to physical knowledge constraints.
Owner:SHANGHAI SHIP & SHIPPING RES INST CO LTD +1

A passive radar target return simulation system

The application discloses a passive radar target echo simulation system, comprising: a radio frequency signal generator, a power division unit and an amplitude and phase control unit connected in sequence; a total control unit connected with the radio frequency signal generator and the amplitude and phase control unit; the total control unit is used for analyzing the received control command, obtaining the passive radar working parameters and target parameters, and converting the passive radar working parameters and target parameters into first control instructions and second control instructions; the radio frequency signal generator is used for generating a reference microwave signal according to the first control instructions; the power division unit is used for dividing the received reference microwave signal into N microwave signals; the amplitude and phase control unit is used for receiving the second control instructions, adjusting the output amplitude and output phase of the N microwave signals according to the second control instructions, and then outputting the N microwave signals after being combined, and the application solves the problems of small instantaneous bandwidth and low simulation precision of multi-target echo characteristics.
Owner:SHANGHAI RADIO EQUIP RES INST

Radar transmit bandwidth augmentation

Various technologies pertaining to forming a very high instantaneous bandwidth (IBW) radar signal based upon several radio frequency (RF) signals that have sub-bands of the frequency band of the radar signal are described herein. A radar system is configured to address local oscillator leakage across multiple transmit channels of the radar system, such that the radar signal has a relatively constant or other desired amplitude and phase across frequencies of the radar signal. In addition, the radar system is configured to compute a correction signal that pre-distorts each of the sub-frequency channels such that upon combining enables the generation of desired amplitude and phase response across a transmitted pulse.
Owner:NATIONAL TECHNOLOGY & ENGINEERING SOLUTIONS OF SANDIA LLC

18-40G transceiver module with 2G instantaneous bandwidth

The invention discloses an 18-40G transceiver module with a 2G instantaneous bandwidth, and relates to the field of signal processing, and the 18-40G transceiver module with the 2G instantaneous bandwidth comprises a down-conversion link which is used for receiving an input 18-40GHz signal, converting the input 18-40GHz signal into a 0.4-2.4 GHz signal after the input 18-40GHz signal is mixed by a frequency hopping local oscillator signal 18-34GHz and a fixed local oscillator signal 9.4 GHz in sequence, and outputting the 0.4-2.4 GHz signal to a baseband processing unit; the local oscillation generation link is used for generating a frequency hopping local oscillation signal 18-34 GHz and a fixed local oscillation signal 9.4 GHz and assisting the down-conversion link and the up-conversion link to work; compared with the prior art, the invention has the following beneficial effects: AD sampling can reach an instantaneous bandwidth of 2GHz by changing a frequency conversion mode; a link is made into a single module, and a VPX connector is used, thereby facilitating the overall plugging, enabling the whole system to be modularized, and improving the integration level.
Owner:WUXI SIEN ELECTRONIC TECH CO LTD

Microwave frequency measurement device based on instantaneous ultra-wideband two-dimensional information mapping

The present invention discloses a microwave frequency measurement device based on instantaneous ultra-wideband dual-dimensional information mapping, which includes a tunable laser, an optical coupler, an intensity modulator, a radio frequency source, an optical filter, an optical amplifier, a circulator, an arbitrary waveform generator, an optical isolator, a high nonlinear optical fiber, a photodetector and an oscilloscope. The present invention obtains the time dimension information corresponding to the frequency of the unknown signal by subjecting unknown signals of different frequencies to the stimulated Brillouin scattering effect to frequency selection of a chirped light pulse sequence, and obtains the amplitude dimension information corresponding to the frequency of the unknown signal by utilizing the response difference of the passband edge of the first optical filter at different wavelengths; the frequency of the unknown signal can be measured with high precision by simultaneously mapping the time dimension information and the amplitude dimension information. The present measuring device can measure single-tone and multi-tone microwave signals at the same time, with fast measurement speed, high measurement accuracy and large instantaneous bandwidth.
Owner:DALIAN UNIV OF TECH