297 results about "Doppler effect" patented technology

The invention provides a system for generating spatially explicit auditory cues for a recipient. It includes a processor to receive real-time location data of multiple physical entities relative to the recipient's spatial position and visual orientation. An audio generation module transforms this data into distinct audio signals using Head-Related Transfer Functions (HRTFs) to simulate perceived direction and distance. The output device, such as a headset or vehicle speakers, presents these audio signals spatially to allow perception of entities' relative locations. The system can adjust volume based on entity distance, integrate Doppler effects to indicate motion, and mute entities outside predefined distance boundaries. It also supports above-ground and ground assets, with altitude information converted to audible cues. The system monitors the recipient's orientation in real-time to adjust the HRTFs accordingly.

The invention relates to an unmanned aerial vehicle detection countering method, which comprises the following steps of: deploying a multi-dimensional sensing network to carry out full-band instantaneous scanning, synchronously acquiring noise characteristics of radio signals, material characteristics of a terahertz wave band and Doppler effect characteristics, mapping to a virtual twinborn body, reconstructing physical parameters, a communication protocol and a behavior mode of a target unmanned aerial vehicle, performing depth comparison by combining a disguise sample library generated by the antagonism generation network, and generating a holographic target file containing a three-dimensional motion vector, an energy feature and a potential threat intention; a target quantum encryption communication link is interfered through a quantum entanglement signal, a controllable plasma cloud cluster is generated, navigation and image transmission signals of the controllable plasma cloud cluster are selectively attenuated, the controllability of the target is judged, and an uncontrollable target is repelled through coded sound waves; and sending a control instruction containing a biological heuristic obstacle avoidance algorithm in stages, and guiding the control instruction to an intelligent recovery cabin. According to the invention, accurate detection, intelligent identification, safe countering and reliable takeover of the unmanned aerial vehicle are realized, and the airspace safety guarantee capability is improved.

The invention discloses an FDA-MIMO radar multichannel coherent accumulation method based on distance-frequency offset compensation, and belongs to the technical field of radar moving target detection. The method comprises the following steps: obtaining an echo signal of a target by using a two-dimensional planar array FDA-MIMO radar; performing multi-channel matched filtering on the echo signal, and performing FFT (Fast Fourier Transform) at slow time to realize pulse accumulation; performing covariance matrix calculation to obtain a noise subspace and a signal subspace; searching an azimuth angle and a pitch angle of the target, and obtaining a distance-frequency offset coupling compensation vector based on characteristic decomposition; and performing multi-channel beam forming, performing coherent synthesis on multi-channel signal energy, and performing target detection by using a constant false alarm rate. According to the method, the output signal-to-noise ratio can be remarkably improved, the calculation complexity of coherent accumulation is reduced, and when an error exists in target distance estimation or a Doppler effect is generated by frequency offset, compared with a MUSIC algorithm, the method can obtain higher coherent accumulation gain.

The invention discloses an optical time stretching sweep frequency interference measurement Doppler effect compensation method and device, and relates to the technical field of non-cooperative target absolute distance measurement. In order to solve the defect that the absolute distance measurement precision is reduced due to the fact that the Doppler effect cannot be efficiently suppressed in a complex environment in the prior art, the technical scheme provided by the invention comprises the following steps: generating a sweep frequency laser signal and splitting the sweep frequency laser signal to form measurement light, reference light and resampling light; performing time stretching processing on the reference light to obtain a chirp signal; performing interference on measurement light and the chirp signal to obtain a measurement interference signal; performing interference on the reference light and the resampling light to obtain a reference interference signal; performing cross-correlation processing on the measurement interference signal and the reference interference signal, and extracting an optical path difference; and carrying out distance calculation by combining the resampling data, and outputting a target distance after the Doppler effect is compensated. The method is suitable for optical measurement work for performing high-precision absolute distance measurement on a non-cooperative target in a tiny vibration or disturbance environment.

The invention relates to the technical field of ship communication, and provides an ocean ship communication method and system based on Ku wave band communication. Comprising the following steps: S1, configuring and deploying a Ku wave band satellite; s2, adjusting the corresponding transmitting frequency through the frequency offset of the transmitting end and the receiving end to perform frequency pre-compensation, converting the transmitted communication data into a satellite signal through modulation and coding by the transmitting end, and transmitting the satellite signal to the receiving end; and S3, capturing and performing down-conversion processing on satellite signals through a satellite antenna and a tuner, analyzing frequency and phase change characteristics of the satellite signals, adjusting parameters of a signal processor for compensation, demodulating and decoding the processed satellite signals through a modem, recovering original communication data, and performing Ku wave band satellite communication through a Ku wave band satellite communication technology. Non-blind area communication coverage of ocean ships is realized, and signal attenuation and interference are reduced by configuring a relay station, expanding the signal receiving and sending range, and dynamically adjusting the signal frequency through adaptive frequency control and a Doppler effect compensation algorithm.

The invention discloses an OFDM-LFM (Orthogonal Frequency Division Multiplexing-Local Frequency Modulation) integrated signal waveform receiving method and equipment based on fractional Fourier transform, LFM and OFDM are combined and improved, an OFDM-LFM integrated radar communication signal taking an orthogonal LFM signal as a subcarrier is adopted, and as the LFM subcarrier has larger Doppler tolerance, compared with a normal subcarrier, the OFDM-LFM integrated signal waveform receiving method and equipment based on fractional Fourier transform have higher Doppler tolerance, the radar communication signal can be received more accurately. The method not only can improve radar distance resolution and spectral efficiency, but also has a strong capability of avoiding Doppler effect, and can reliably transmit information, and when OFDM-LFM signals are received, in order to solve the problems of subcarrier frequency linear transformation, radar parameter extraction and the like, based on the sensitivity of fractional Fourier transform (FRFT) to LFM signals, the method can be used for solving the problems of subcarrier frequency linear transformation, radar parameter extraction and the like. According to the invention, the FRFT is used as the integrated signal receiver, the separation of the integrated signal communication receiver and the radar receiver is realized, and the system performance is improved while the complexity of the system is reduced.

The invention provides a timing synchronization recovery system based on a Gardner algorithm, relates to the technical field of signal processing, and is used for solving the problem that in the prior art, in long-distance communication, due to the fact that signals are affected by noise and errors caused by factors such as atmospheric turbulence and Doppler effect in the transmission process, the transmission efficiency of the signals is improved. And complete synchronization of the clock, the phase and the frequency is difficult to guarantee. The system comprises a signal sending end used for generating a random binary signal and modulating the binary signal into a simulation signal suitable for transmission, and the simulation signal is used for simulating transmitted bit data; the channel is used for transmitting the simulation signal and introducing noise in the transmission process to carry out simulation interference on the simulation signal to obtain a distortion signal; and the signal receiving end is used for receiving the distorted signal, performing timing synchronization and interpolation processing on a symbol of the distorted signal by using a Gardner loop, correcting a sampling deviation introduced by a channel, and recovering original bit data from the distorted signal.

The invention discloses a hydropower station water level detection method and system. The method comprises the steps that an original water flow characteristic parameter set is obtained through multiple sets of Doppler effect radar flow measuring devices; performing segmentation extraction to obtain a water flow feature sub-data set; inputting a Transform network coding layer to generate a water flow feature coding vector; outputting a preliminary water level predicted value sequence through a decoding layer; a radar flow measurement model is called for correction to obtain a correction sequence; time sequence integration is carried out to obtain a water level change curve. The system comprises a multi-source Doppler radar signal acquisition unit, a spatial-temporal feature segmentation extraction unit, a Transform coding processing unit, a water level preliminary prediction unit, a radar model correction unit and a time sequence integration output unit. According to the method and system, multi-source parameters are deeply fused, the environmental adaptability is improved, the continuity and reliability of a detection result are enhanced, the water level of the hydropower station can be accurately monitored, and support is provided for scheduling decision and safety prevention and control.

The invention discloses a frequency spectrum refining frequency point tracking type optical frequency domain reflection distributed sensing method, which comprises the following steps of: inputting probe light into a sensing optical fiber engraved with weak reflection points to obtain backscattered light; carrying out coherent frequency mixing on the backscattered light and the reference light, and then carrying out photoelectric conversion to obtain an electric signal containing weak reflection point information; aD sampling is carried out on the electric signal containing the weak reflection point information, and a first discrete signal sequence is obtained; performing frequency spectrum refinement on the first discrete signal sequence to obtain a refined beat frequency spectrum; performing peak searching operation on the refined beat frequency spectrum to obtain weak reflection beat frequency points at different positions in different measurement periods; extracting phase values of beat frequency points of weak reflection points at different positions in different measurement periods by utilizing Hilbert transform; and carrying out phase demodulation on the phase values of the beat frequency points of the weak reflection points at different positions in different measurement periods to obtain the change condition of parameters measured by the sensing optical fiber. Errors caused by the Doppler effect can be eliminated.

The invention discloses a wavelength division multiplexing-based all-fiber mirror image frequency sweeping interference distance measuring device and method, and relates to the technical field of absolute distance measurement. The objective of the invention is to solve the technical problems in the prior art that frequency spectrum aliasing, frequency sweep nonlinearity, Doppler effect and dispersion mismatch occur in frequency sweep interference measurement, and the measurement precision, the measurement efficiency and the reliability of an all-fiber mirror image frequency sweep interference ranging system cannot be ensured. According to the technical scheme provided by the invention, the wavelength division multiplexing-based all-fiber mirror image frequency sweeping interference distance measuring device comprises a laser unit used for outputting frequency sweeping light; the measurement interferometer light path is used for generating a measurement signal according to the sweep frequency light; the auxiliary interferometer light path is used for generating an auxiliary signal according to the sweep frequency light; the gas chamber calibration light path is used for carrying out auxiliary interferometer light path calibration according to the sweep frequency light; and the data acquisition and processing module is used for obtaining a distance measurement result according to the measurement signal, the auxiliary signal and the calibration signal. The method is applied to the work of all-fiber mirror image frequency sweeping interference distance measurement.

The invention provides an underwater ultrasonic signal analysis method based on the Doppler effect, and relates to the technical field of data processing, and the method comprises the steps: carrying out the segmentation processing of echo signal data according to a preset time window, carrying out the envelope demodulation and phase unwrapping operation of a signal in each time window, and carrying out the phase unwrapping operation of the signal in each time window; amplitude sequence, phase sequence and instantaneous frequency sequence data are extracted; extracting frequency change, amplitude change and phase change data, performing clustering processing, and distinguishing and marking different underwater target components; respectively calculating an amplitude stability index and a phase change synchronism index for each frequency track in all time windows, and screening a main frequency track according to the amplitude stability index and the phase change synchronism index; frequency shift values in the time windows are extracted, the speeds of the underwater targets in the time windows are calculated based on the Doppler effect, and the motion direction is judged in combination with frequency change data and phase change data; according to the invention, the autonomy and accuracy of underwater ultrasonic signal analysis are improved.

Autonomous ground vehicles that are outfitted with radar sensors and inertial measurement units accurately determine states of the autonomous ground vehicles, e.g., estimates of the vehicles' positions, orientations, or velocities or accelerations along or about one or more axes, based on data captured by the radar sensors and the inertial measurement units. Where objects are detected in radar scans, the objects are determined to be static (or fixed), or dynamic (or moving), and landmarks representing static objects are identified. Constraints on estimates of states may be calculated based on doppler effects, inertial measurement unit effects, or locations of landmarks, and the states may be determined as solutions to optimization problems based on the data and the calculated constraints. Odometry messages representing the determined states may be generated and stored or utilized for any purpose.

The invention discloses a grating displacement encoder grating spacing error in-situ detection and self-compensation method, and belongs to the technical field of optical measurement, and the method comprises the steps: generating elliptically polarized light, modulating the elliptically polarized light into S polarized light, reflecting the S polarized light through a polarization beam splitter, converting the S polarized light into circularly polarized light through a quarter-wave plate, and enabling the circularly polarized light to enter a diffraction grating ruler; the diffraction grating ruler diffracts incident light to form first-order diffraction light and second-order diffraction light; processing and interference detection are carried out on the first-order diffraction light, and precise displacement conversion is carried out in combination with the Doppler effect of grating displacement; constructing an auto-collimation angle detection sensing module by using second-order diffraction light, and converting the distance manufacturing deviation of diffraction gratings by detecting the tiny change of a diffraction angle; and compensating the displacement measurement error of the grating encoder in real time according to the real-time detection result of the grating spacing manufacturing deviation. According to the invention, the off-line detection time and cost of the grating are greatly saved.

The invention relates to the field of network security and the deep learning field, in particular to a satellite internet-oriented Tor website fingerprint identification method, which is implemented by constructing a self-supervised contrast learning framework and is implemented by generating a multi-view sample; extracting a feature matrix of the time sequence granularity; generating a synthesized negative sample based on linear insertion, and constructing a contrast with the positive sample; and track representation is extracted, and joint optimization is carried out in combination with cross entropy loss and mask reconstruction loss. Compared with a traditional website fingerprint identification method, the robustness of the model to satellite inherent noise caused by the Doppler effect can be enhanced. According to the method, multi-scale semantic features are provided for the weak enhancement view and the strong enhancement view, the inter-class distinction degree is improved by synthesizing negative samples, and the misjudgment rate is reduced; the joint loss optimization framework enables the model to give consideration to global statistical characteristics and local burst characteristics, and under the conditions of strong dynamic topology and limited labeling of satellite internet constellations, the accuracy and adaptability of website fingerprint recognition are remarkably improved.

A system for millimeter RADAR object recognition and classification using sub-band frequency interference and resonance effects from primary targets signals and reflected signals from secondary target preferably in the form of Wideband Chaos Generating Material (WCGM) objects, preferably detecting frequency dependent absorbing material, frequency dependent resonance effects from the second and primary target objects, frequency signal resonance effects caused by water molecule dipole effects in different sugar solutions, impedance of material, shape of metamaterial, and interference effects due to combination of signal sources resulting in a wider range of transmitter and scanning frequency band for RADAR based interrogation of target objects. The RADAR system makes opportunistic use of traditionally seen problematic interference signals, as extra signal sources providing extended range and frequency bandwidth for frequency-based interrogation of target object signatures in a frequency-intensity plane, a frequency-polarization plane, and a frequency-phase shift plane for doppler effects.

The invention provides an intelligent reflection surface assisted low-altitude unmanned aerial vehicle Doppler-polarization combined beam forming system, and relates to the technical field of low-altitude communication, and the system comprises an unmanned aerial vehicle-mounted communication platform, a ground base station, a distributed deployment intelligent reflection surface array and a cooperative control system. According to the method, a joint channel model capable of capturing high-speed movement and a polarization effect is constructed; a Doppler polarization combined sensing and beam forming algorithm based on the model is designed, and processing is carried out on an unmanned aerial vehicle platform and / or a base station side; an IRS reflection coefficient optimization strategy considering Doppler and polarization characteristics is provided; and a set of self-adaptive cooperative control mechanism is established. Through cooperative work among the unmanned aerial vehicle end, the base station end and the IRS, the system can effectively compensate the Doppler effect and intelligently reconstruct a propagation environment by using polarization information and by means of the IRS, so that high-reliability, strong-anti-interference and large-coverage wireless communication is realized in a complex low-altitude dynamic environment.

The invention relates to a radar identification warning method applied to an electric power line protection area, and relates to the technical field of electric power monitoring. According to the method, radar working parameters are configured by using an environment-corrected radar equation and a genetic algorithm considering a radar coverage range, radar detection accuracy and radar energy consumption; the radar detects a target in a power line protection area to obtain radar point cloud data; in the process, multi-frequency fusion ranging is used for measuring the distance of a target, and the Doppler effect is used for resolving the speed of the target; detecting and repairing abnormal values of the radar point cloud data based on an isolated forest algorithm; inputting the preprocessed radar point cloud data into a pre-trained integrated learning classifier for target identification, and obtaining target category information, speed, distance, environment data and facility operation data as risk assessment data; the risk assessment model assesses a target risk according to the risk assessment data to obtain a target risk value and a risk level probability; and performing graded warning according to the target risk value and the risk grade probability.

The invention discloses an unmanned aerial vehicle monitoring method and system in a complex electromagnetic environment, and the method comprises the steps: extracting a signal feature from a spectrum signal collected in real time, and obtaining a first feature vector; adopting a pre-constructed random forest model to classify the first feature vectors and match the first feature vectors with known unmanned aerial vehicle information to obtain a first model and a first serial number of the unmanned aerial vehicle; according to the coordinates of the at least three measurement stations, calculating the three-dimensional coordinates of the unmanned aerial vehicle by adopting a time difference of arrival positioning technology and an angle of arrival measurement technology; calculating the radial speed of the unmanned aerial vehicle relative to each measurement station by adopting a Doppler effect, and calculating a three-dimensional speed vector of the unmanned aerial vehicle according to the radial speed; and according to the three-dimensional coordinates and the three-dimensional speed vector of the unmanned aerial vehicle, predicting the change trend of the three-dimensional coordinates and the three-dimensional speed vector of the unmanned aerial vehicle in a preset time window by adopting a particle filtering algorithm. By adopting the embodiment of the invention, the identification accuracy, the positioning precision and the anti-interference capability of unmanned aerial vehicle monitoring in a complex electromagnetic environment can be improved.

The invention provides an inter-satellite link bidirectional measurement method based on a same-time same-frequency full-duplex system, which overcomes the problem that receiving and transmitting of a traditional time-division half-duplex system cannot work at the same time and at the same frequency, and can effectively improve the information transmission rate and the ranging precision. The inter-satellite transmission rate, the measurement frequency and the data updating rate can be doubled; simultaneous and same-frequency measurement between satellites can greatly eliminate distance measurement errors caused by relative motion between satellites, clock skew and Doppler effect; a complex orbit model does not need to be established to improve the distance measurement precision, the time scale reduction error is greatly reduced, and the overall measurement performance is improved.

The invention discloses a laser vibration meter series reciprocating type optical frequency modulation calibration method and device, and belongs to the field of photoelectric measurement. The calibration device is mainly composed of a calibrated laser vibration meter, a first acousto-optic modulator, a second acousto-optic modulator, a lens, a first sinusoidal signal source, a second sinusoidal signal source, an FM signal source and a plane mirror. Aiming at a laser signal emitted by the laser vibration meter, the reversibility characteristic of a light path is utilized, a straight-line-shaped light path structure is used, a secondary light frequency modulation mode of the same group of optical devices is combined with secondary light frequency translation to realize output frequency translation and modulation control of the laser vibration meter, and a laser Doppler effect caused by different vibration waveform magnitude values is simulated. And the modulated laser is completely returned to the calibrated laser vibration meter in the original path, so that the change waveform of the vibration velocity value is replaced by the change waveform of the frequency value, and the calibration of the laser vibration meter is realized. The device has the advantages of portability, wide frequency range, wide amplitude range calibration, high precision and good stability.

The invention provides a low earth orbit satellite signal capturing method based on PMF-FFT. The low earth orbit satellite signal capturing method comprises the steps that firstly, low earth orbit satellite downlink signals are received and frequency mixing is carried out; carrying out adjustable parameter window adding processing on the frequency-mixed signal; inputting the windowed signal into a PMF module, and carrying out correlation calculation on the windowed signal and a local pseudo code to obtain PMF module output; carrying out adjustable parameter window adding processing on the output of each segmented matched filter in the PMF module; performing N-point FFT on the output result of the segmented matched filter; performing normalization processing on the FFT result of the # imgabs0 # point to obtain a normalized amplitude-frequency response; and performing threshold judgment according to the normalized amplitude-frequency response to realize capture. The method not only solves the problems of difficulty in broadband capture, long capture time and poor anti-Doppler effect of the traditional signal capture method, but also solves the problem that the traditional PMF-FFT method cannot break through a preset capture threshold and misses capture due to the fact that the normalized power spectral density at the target Doppler frequency shift is reduced due to energy loss under the condition of low signal-to-noise ratio. Therefore, the low-orbit satellite navigation signal can be quickly captured.

The invention discloses a signal transmission method, system and device based on generalized chirp division multiplexing and a medium, and the method comprises the steps: employing a specific pulse forming window for each chirp subcarrier at a transmitting end, and employing a matching filtering window for each chirp matching subcarrier at a receiving end; fractional time delay and fractional Doppler effects introduced by a double-dispersion channel in a communication system, namely diffusion of received symbols, are suppressed, sparsity of an equivalent channel of the system is improved, and interference between symbols received by a communication receiving end is greatly reduced. The diffusion degree of a receiving pilot symbol for channel estimation is slowed down, so that the channel estimation is more accurate, the number of protection symbols required by a sending end is reduced, and the reachable capacity of a communication system is improved; compared with the prior art, an equivalent channel is more sparse, interference between a pilot symbol and a data symbol of a receiving end is reduced, so that pilot-data separability of the system is higher, signal detection complexity of the communication system is lower, and the detection effect is better.

The invention belongs to the technical field of mobile communication, and particularly relates to an orthogonal time-frequency air conditioning-based integrated waveform design method, which comprises the following steps of: constructing a receiving and transmitting filter bank with a frequency spectrum shaping characteristic on a time domain level, converting an item with a complex analytic expression in a traditional architecture into a scaling factor capable of being linearly processed, and carrying out linear processing on the scaling factor; architectural simplification of a sensing signal processing flow is realized; on a delay Doppler domain level, aiming at an inter-Doppler interference mechanism caused by static environment clutter coupling and a fractional Doppler effect, a pilot frequency sequence matrix with a strong self-correlation main lobe and a weak cross-correlation side lobe is innovatively constructed, and accurate separation of aliasing echoes is realized by using a sharp delay-Doppler resolution characteristic of the pilot frequency sequence matrix. According to the scheme, through the cross-domain cooperation mechanism, on the premise of maintaining the communication sensing dual-mode performance, double breakthrough of signal processing architecture simplification and pilot frequency overhead optimization is achieved, and an innovative design framework is provided for a communication sensing integrated system in a mobile scene.

The invention provides a radar system for pipeline inner wall modeling and a pipeline inner wall modeling method, and relates to the technical field of radar application, the system comprises a millimeter wave radar and a laser radar; the millimeter wave radar is configured to emit electromagnetic waves to the inner wall of a to-be-measured pipeline and receive reflected waves of the electromagnetic waves. Based on the reflected waves, using Doppler effect and echo analysis operation to generate structural data of the inner wall of the to-be-detected pipeline; the laser radar is configured to emit a laser beam to the inner wall of a to-be-detected pipeline and receive a reflection signal of the laser beam; according to the reflection signal, calculating the flight time or phase difference of the laser beam, and generating 3D point cloud data of the inner wall of the to-be-detected pipeline; the modeling module is configured to fuse the modeling data by using an MLS algorithm to obtain modeling fusion data; and on the basis of the modeling fusion data, utilizing a Poisson reconstruction model to generate an inner wall model of the to-be-measured pipeline, so as to solve the problem that the existing single radar system is difficult to perform high-precision accurate modeling on the inner wall of the pipeline.

In aspects, a coordinating base station that forms an active coordination set (ACS) is described that includes at least the coordinating base station and a non-terrestrial network base station (NTN BS) for joint-communication with a user equipment (UE). Based on an evaluation of terrestrial channel conditions for the UE, the coordinating base station selects one or more non-terrestrial NTN BSs as candidate base stations to add to the ACS. The coordinating base station transmits ephemeris information for the one or more NTN BSs to the UE. The UE acquires and measures signal quality of each of the NTN BSs and sends an indication to the coordinating base station. Based on the indication, the coordinating base station sends an invitation to the NTN BS to join the ACS which communicates using timing and frequency compensation to compensate for distance and Doppler effects.

The invention discloses an OTFS signal-based high-precision target parameter estimation method for a common-inductance integrated system, which is based on a recursive optimization super-resolution estimation algorithm, combines a grid refining method and a recursive optimization strategy, and adopts a two-stage estimation framework. In the first stage, super-resolution estimation of time delay and Doppler frequency shift is realized through a grid refinement technology, and the estimation precision is improved; and in the second stage, a multi-path interference recursive optimization mechanism is combined, so that the influence of a multi-path effect on estimation precision is effectively reduced, and the reliability and robustness of estimation are further improved. Under the condition of processing fractional time delay and Doppler frequency shift, the method provided by the invention obviously improves the estimation precision in a complex channel environment, and can effectively solve the problem of parameter estimation under fractional time delay and Doppler effect.

The invention discloses a different-orbit inter-satellite communication link beam pointing error calculation method, which relates to the technical field of communication, introduces high-order perturbation modeling, solar radiation pressure, earth tidal effect and moon gravitational perturbation items, effectively simulates orbit change of a satellite disturbed by external gravitational force for a long time, reduces the accumulation effect of errors, and improves the accuracy of beam pointing error calculation. In long-time or high-orbit satellite communication, pointing errors caused by simplified perturbation can be effectively reduced, relative motion models of two different-orbit satellites are combined, orbit change of a single satellite is integrated, change of relative speed is taken into calculation, wave beam pointing can be dynamically adjusted when the relative position and the speed of the satellites change, and the method is suitable for large-scale popularization and application. Errors caused by relative movement are reduced, meanwhile, a coupling model of frequency deviation and beam pointing angle deviation is constructed, the influence of the Doppler effect on beam pointing is predicted and corrected in real time, the beam pointing is dynamically adjusted through coupling correction, communication signals are kept on the optimal transmission path, and frequency deviation is avoided.

The invention relates to driver monitoring, in particular to a driver monitoring method based on high-frequency sound wave modeling, and the method comprises the steps: transmitting high-frequency sound waves into a vehicle; when the driver is in the normal driving state, echo signals reflected in the vehicle are received, and a reference sound wave feature library about the limbs of the driver is established; disturbed echo signals in the vehicle are collected in real time, and to-be-recognized sound wave features about the limbs of the driver are extracted; inputting the to-be-recognized acoustic wave features into the trained action recognition model to obtain an action recognition result; the Doppler effect of the echo signals is analyzed, the motion direction and speed of the motion are obtained, and the motion frequency is determined; performing graded early warning by combining the action recognition result, the motion direction and speed of the action and the action frequency; according to the technical scheme provided by the invention, the defect that the action of the driver is difficult to accurately recognize in the prior art can be effectively overcome.

According to the unmanned aerial vehicle capturing method and device, the electronic equipment and the storage medium, the operation sound and image of the unmanned aerial vehicle are collected, the recognition reliability is improved by using double information sources, and whether the target object is the unmanned aerial vehicle or not can be more accurately judged in combination with the sound features and the image features, so that the recognition accuracy is remarkably improved. In addition, the motion state of the unmanned aerial vehicle is analyzed by using a Doppler effect algorithm, and the operation speed of the unmanned aerial vehicle is identified in combination with an optical flow algorithm, thereby realizing comprehensive monitoring of the motion state of the unmanned aerial vehicle. The multi-dimensional monitoring mode not only improves the accuracy of unmanned aerial vehicle position determination, but also provides powerful data support for subsequent unmanned aerial vehicle capture, so that the accuracy of unmanned aerial vehicle identification and the success rate of capture can be significantly improved.

The invention relates to the technical field of radar imaging, and discloses a synthetic aperture radar forward oblique imaging polar coordinate imaging algorithm, which comprises the following steps: acquiring an electromagnetic signal reflected when a radar wave reaches a detection target and flight path data of the radar wave, performing data preprocessing, and establishing echo data; and converting a rectangular coordinate system of the echo data into a polar coordinate system, and carrying out gridding processing. And removing the Doppler effect in the echo data after gridding processing based on a distance Doppler algorithm, and determining the azimuth of the echo data based on polar coordinate fast Fourier transform. And based on a pre-configured view angle, dividing the echo data after the Doppler effect is removed into a plurality of sub-regions for block processing, and reconstructing an image to be generated. And performing image filtering enhancement and artifact elimination on the to-be-generated image, and converting the to-be-generated image into a standard image format for output. According to the invention, through signal processing and image reconstruction technologies, the accuracy and reliability of radar imaging can be effectively improved.