66 results about "Frequency code" patented technology

The invention provides a three-dimensional intelligent sorting method and system for dangerous goods logistics. Multi-frequency-band sound wave signals are emitted in a storage space through a sound wave standing wave array, a three-dimensional frequency coding grid is formed through standing wave interference, millimeter-level accurate positioning of a dangerous goods container is achieved, and a sorting execution instruction is generated. Airfoil piezoelectric ceramics of the aircraft receive sound wave signals and convert the sound wave signals into flight attitude parameters, a sorting path is planned in combination with a path tracking algorithm, meanwhile, a dynamic sorting channel opening is generated through airfoil flutter frequency and sound wave standing wave resonance, and a leakage container is accurately guided to be transferred to an isolation area. According to the method, the accuracy and efficiency of dangerous goods sorting can be remarkably improved, the risk of manual intervention is reduced, and a whole-process intelligent solution is provided for storage safety.

The invention particularly relates to a miniaturized broadband instantaneous frequency measurement receiver and a corresponding data processing method. The miniaturized broadband instantaneous frequency measurement receiver comprises a signal input port used for receiving an original radio frequency signal; the amplifying and filtering module is used for amplifying and filtering the original radio frequency signal and then outputting a first radio frequency signal; the first power divider is used for splitting the first radio frequency signal and outputting the first radio frequency signal to the multi-channel power division phase discrimination assembly; the multi-channel power division and phase discrimination assembly comprises a plurality of power division and phase discrimination modules and is used for carrying out instantaneous measurement on the signal frequency of the first radio frequency signal and outputting multi-channel video signals; the frequency measurement coding module is used for performing frequency measurement processing on the video signal and outputting a frequency code; wherein the signal input port is connected with the amplification filtering module and the power division phase discrimination module through microstrip lines; the power division phase discrimination module is connected with the frequency measurement coding module through a glass insulator. The size, the volume and the weight of the device all meet the requirement for miniaturization.

The invention belongs to the technical field of communication, and relates to a time-frequency multi-dimensional coding frequency hopping communication method and device based on Rydberg atoms. Comprising the following steps: exciting a cesium atom system from a ground state to an intermediate excitation state by utilizing probe light, and exciting the cesium atom system from the intermediate excitation state to a Rydberg state by utilizing coupling light; determining the resonant frequency and the non-resonant frequency of a carrier based on the energy level of the cesium atom system in the Rydberg state, and selecting the carrier of the resonant frequency or the non-resonant frequency according to the binary state of the baseband signal to perform time-frequency coding to generate a frequency hopping sequence; and radiating the frequency hopping sequence to a cesium atom system in a Rydberg state, and receiving a spectral signal of the transmissivity of the detection light passing through the cesium atom system so as to complete receiving of a baseband signal. According to the invention, frequency hopping sequence synchronization and signal modulation are not needed, the complexity of the system is reduced, and the method has the characteristic of tracking interference resistance.

The invention relates to the technical field of electric digital data processing, and provides a transmission data compression method and system based on cloud computing, and the method comprises the steps: collecting system log data, obtaining a to-be-compressed character string and a to-be-compressed character string set, obtaining a high-frequency code according to the to-be-compressed character string set, and calculating the global redundancy high frequency of the to-be-compressed character string; according to the global redundancy high frequency and the high frequency code of the to-be-compressed character string, the redundancy matching density and the global compression gain degree of the to-be-compressed character string are obtained, then the to-be-compressed character string is subjected to global compression according to the global compression gain degree of the to-be-compressed character string, and then the global compression character string is compressed by using an LZ77 compression algorithm. And then transmission of the system log data is completed. The method aims at solving the problems that an existing LZ77 compression algorithm only considers local similarity, and the compression efficiency of system log data with high global repeatability is not high enough.

The invention discloses a ground feature classification method based on a frequency-space collaborative learning hierarchical fusion network. The method comprises the following steps: step 1, data preparation; step 2, the HMFE module extracts frequency domain features; step 3, extracting spatial domain features by an MLSA module; 4, the AWF module dynamically integrates the features; 5, executing a classification task; the MLSA module strengthens cross-scale interaction through a tree fusion structure and a cross attention mechanism, realizes efficient fusion of HSI and LiDAR data in a spatial domain, improves classification consistency of complex scenes, and reduces boundary blur phenomena; the HMFE module introduces a learnable frequency coding mechanism into the Mmba module so as to enhance spectrum-frequency components with strong discrimination; the AWF module realizes dynamic integration of spatial domain and frequency domain features through adaptive weighted fusion, fully mines deep complementarity of the spatial domain and the frequency domain, and improves the utilization efficiency of the model for heterogeneous data.

The invention discloses a cross-modal fusion and multi-frequency coding view angle image generation method in an ultra-low orbit scene, and solves the problem of view angle condition generation and single image three-dimensional reconstruction method based on diffusion prior in the ultra-low orbit scene of an aircraft target. Due to insufficient condition information fusion capability, limited radiation or illumination characterization and insufficient cross-view-angle geometric constraint, a problem that a new view angle image with visual coherence and geometric consistency of texture details is difficult to obtain at the same time under large-range view angle and scale change is solved; according to the method, multi-order angle information of direction distribution is effectively captured through perceptual coding of a light direction vector, then the position of a light starting point coordinate is coded, and finally the pose of a camera pose parameter is coded, so that the influence of a relative pose on depth perception and perspective distortion in an image generation process can be depicted; the three coding results are used for a decoding stage of the potential diffusion model, and geometric consistency of detail recovery under a new view angle is effectively improved.

The invention discloses a signal control system for a mining locomotive, and aims to solve the problems of weak interference resistance and low safety of a traditional system. The system comprises a signal acquisition module, a dynamic frequency coding processing module, an intelligent decision-making module, an execution module, a communication module and a power supply module. The signal acquisition module acquires the position, speed and environmental parameters of the locomotive through an infrared position, speed and temperature and humidity sensor; the dynamic frequency coding module monitors the signal-to-noise ratio of a sub-band every 10 ms, when the signal-to-noise ratio of the sub-band is lower than 15 dB, the sub-band is automatically switched to a high-signal-to-noise-ratio sub-band larger than or equal to 20 dB, an encryption mapping table is generated for synchronous updating, and the equipment deals with sudden interference through an emergency band. The intelligent decision-making module generates a control instruction, and speed adjustment and parking are achieved through the execution module. An explosion-proof cable and a low-frequency through-the-earth technology are combined for communication, and a power supply is of an explosion-proof type and has multiple protections. The system improves the anti-interference performance and safety of signal transmission, adapts to the mine environment, and supports the intelligent operation of mine transportation.

The invention discloses a test method for keeping human control priority for side line pull-in of a CTCS-2 vehicle-mounted train control system, which comprises the following steps: a vehicle-mounted device controls a train to run to a turnout side line train connection track in an FS mode, and receives low-frequency code information sent from a track circuit; determining a turnout type and a test case according to the low-frequency code information; executing the test case to obtain a test result; the test case comprises the following steps: executing the position of the mobile authorization length at the outbound signal machine; receiving a codeless / HU low-frequency code sent by the track circuit in a front bifurcation area; receiving the HU low-frequency code sent by the track circuit in the station; determining whether to reopen the outbound signal machine; and checking the DMI of the vehicle-mounted equipment to determine whether the vehicle-mounted train control system is in a manual control priority mode or not, and obtaining the test result. According to the invention, the test of keeping the man-control priority mode function of the side-line pull-in train is realized, the integrity of test coverage is ensured, and the test efficiency is effectively improved.

The invention relates to the technical field of wireless communication, in particular to an intelligent lock anti-interference wireless communication method and system based on metamaterial resonance. The method comprises the steps that preset frequency-phase combination parameters of a metamaterial resonant antenna are initialized at an intelligent lock end, 128 kinds of orthogonal frequency division multiplexing waveforms are corresponding, and the metamaterial resonant antenna only responds to excitation signals containing preset frequency-phase combinations so as to filter interference signals of non-matched frequencies and phases. According to the invention, an anti-interference wireless communication system based on metamaterial resonance is constructed at the intelligent lock end, so that deep fusion of physical layer signal screening and a protocol layer security mechanism is realized. Specifically, a preset frequency-phase combination parameter of the metamaterial resonant antenna and a dynamic time-frequency coding hopping sequence form dual-frequency phase filtering, only a signal matched with the resonance characteristic of the current communication period is allowed to enter a demodulation process, and interference signals of non-matched frequencies and phases are effectively suppressed from a physical layer.

The invention relates to the field of sensor communication, in particular to an intelligent sensor communication method. The method comprises the following steps: acquiring a physical quantity signal in an environment by using an intelligent sensor, generating a corresponding time domain signal, and converting the time domain signal into a frequency domain signal; based on the frequency domain signal, using a dynamic frequency hopping and power consumption perception optimization algorithm to select an optimal frequency; based on the optimal frequency, performing data block coding by using a nonlinear multi-level frequency coding algorithm; and evaluating the path state and the channel performance by using a path optimization selection algorithm, and calculating to obtain the optimal transmission path of each data block. The problems of frequency band overlapping and interference in sensor data acquisition are solved; the problems of fluctuation and inconsistency of sensor signals caused by changes of environmental conditions, reduction of signal reliability due to interference among different frequency channels, signal distortion due to frequency band interference among different data blocks, and fluctuation of channel quality and bandwidth of different paths along with time are solved.

The invention provides a method for transmitting a low-frequency code sequence by a train control center and processing the low-frequency code sequence by a vehicle-mounted device and a train control system, and the train control center not only can transmit the low-frequency code sequence to the vehicle-mounted device based on a track circuit interface, but also can directly transmit the low-frequency code sequence to the vehicle-mounted device based on wireless communication. Therefore, the problem that in the prior art, a train control center can only send low-frequency code sequence information to vehicle-mounted equipment through a single track circuit interface is solved. Under the scene of track circuit interface single-channel link failure, a train control center uses a redundant channel to continuously provide driving permission information for vehicle-mounted equipment, and the train operation efficiency and the line transport capacity are improved.

The application provides a waveform design and receiving method in orthogonal time-frequency code domain. The method comprises the following steps: allocating orthogonal spread spectrum combination to each waveform in a waveform group by using an orthogonal spread spectrum sequence pool; each waveform carries transmission data in the orthogonal time-frequency code domain according to the allocated orthogonal spread spectrum combination; after receiving each waveform, a receiver estimates the multipath time delay, multipath fading and multipath Doppler experienced by multiple waveforms according to the orthogonal spread spectrum combination of each waveform; the receiver detects the transmission data carried by each waveform by using the estimated multipath time delay, multipath fading and multipath Doppler of each waveform, using the MMSE criterion and the orthogonal spread spectrum combination structure. The method of the application designs unique orthogonal spread spectrum combination for different waveforms in the same waveform group, realizes the orthogonal transmission of multiple waveforms under the same DD domain resource, and provides an alternative scheme for multi-user data transmission under high-speed mobile conditions.

The invention discloses a method for distinguishing and quantifying an unconventional oil reservoir CO2 huff and puff recovery ratio improving mechanism, and relates to the technical field of petroleum and natural gas extraction. According to the method, a saturated oil core T2 spectrum and a one-dimensional frequency code are measured on the basis of a nuclear magnetic resonance (NMR) experiment, and the CO2 huff and puff recovery ratio and the CO2 effective action distance are calculated by analyzing the saturated oil core T2 spectrum and the one-dimensional frequency code; a component model is established and calibrated based on experimental data so as to fit the recovery ratio and the CO2 effective action distance in the experiment, and then EOR mechanisms of different CO2 huff and puff stages are distinguished and quantified. According to the method, the yield increasing mechanism in the CO2 huff and puff process can be accurately divided into oil expansion, oil molecule diffusion, elastic energy release and dissolved gas drive, the main control mechanism of CO2 huff and puff yield increasing can be effectively judged, and a basis is provided for optimization of field operation.

The invention belongs to the technical field of electrocardio time sequence data processing, and discloses an electrocardio anomaly detection method based on time-frequency enhanced self-supervised contrast learning, which comprises the following steps: acquiring frequency sample data of an electrocardio signal, and performing time-frequency conversion to obtain time sample data; obtaining a time coding sequence and a frequency coding sequence; establishing an intra-time-frequency comparative learning convolutional neural network model, and training the intra-time-frequency comparative learning convolutional neural network model by using the positive sample pair; establishing an inter-time-frequency comparative learning convolutional neural network model, and training the inter-time-frequency comparative learning convolutional neural network model by using the positive sample pair; guiding model convergence by using a total loss function to obtain a trained time-frequency internal comparative learning convolutional neural network model and a trained time-frequency internal comparative learning convolutional neural network model; real-time electrocardiosignals are collected, and electrocardiosignal anomaly detection is carried out according to the steps. According to the method, the accuracy of abnormal electrocardiogram detection is improved through an intra-time-frequency and inter-time-frequency comparison learning mechanism.

The invention discloses a lumbar vertebra scanning processing method and device, a storage medium and electronic equipment, and the method comprises the steps: obtaining a sagittal three-dimensional image of a lumbar vertebra, carrying out the three-dimensional segmentation of the lumbar vertebra and an intervertebral disc in the sagittal three-dimensional image, and obtaining a lumbar vertebra segmentation result and an intervertebral disc segmentation result; inputting the lumbar vertebra segmentation result and the intervertebral disc segmentation result into a preset anatomical key point detection network for anatomical key point identification to obtain an anatomical key point set, and constructing a local vector space based on the anatomical key point set, according to a preset magnetic resonance lumbar vertebra scanning constraint rule, target scanning positioning parameters corresponding to multiple target scanning orientations are matched in the local vector space, and the target scanning positioning parameters at least comprise a phase coding direction, a frequency coding direction, a slice selection direction and a slice center position; and controlling magnetic resonance equipment to execute lumbar vertebra scanning based on the target scanning positioning parameter. The lumbar vertebra scanning parameter planning can be automatically completed.

The invention belongs to the technical field of software testing, and relates to a test case dynamic sorting method and system based on hot area identification and defect prediction. The method comprises the steps of collecting multi-modal data in real time; a time decay sliding window algorithm is adopted to calculate the code change density, and hot area self-adaptive classification is carried out; a defect feature vector is output through a DefectBERT model, and the correlation degree between the test case and the defect is calculated; dynamically distributing the weight of each feature through an adaptive weight adjustment mechanism, and carrying out adaptive feature fusion; predicting a defect probability by adopting an LSTM-GRU combined network, and generating a test case priority queue; the weight parameters of the four-dimensional features are adjusted in real time through a PID weight controller. According to the method, the test efficiency is improved, the defect detection rate is increased, the false alarm rate is reduced, the dynamic adaptability is enhanced, a high-frequency code change scene can be adapted through hot area dynamic division and weight self-adaptive adjustment, and the real-time requirement of a continuous integration environment is met.

The application discloses a kind of viewgraph generation methods of cross-modal fusion and multi-frequency coding under ultra-low orbit scene, solve the ultra-low orbit scene of aircraft target, based on the generation of view condition and single picture three-dimensional reconstruction method of priori diffusion, because of insufficient condition information fusion ability, radiation or illumination representation is limited and cross-view geometric constraint is insufficient, it is difficult to obtain the problem that visual coherence and geometric consistency of new view image with texture details under large range of view and scale change simultaneously;The application effectively captures the multi-order angle information of direction distribution to the perception coding of light direction vector, then encodes the position of light starting coordinate, finally encodes the pose of camera pose parameter, can depict the influence of relative attitude on depth perception and perspective distortion in image generation process;The above three encoding results are used in the decoding stage of latent diffusion model, effectively improve the geometric consistency of detail recovery under new view.

This invention discloses a testing method for maintaining human control priority for lateral entry trains in the CTCS-2 onboard train control system. The method includes: the onboard equipment controlling the train in FS mode to run to the turnout lateral receiving track and receiving low-frequency code information sent from the track circuit; determining the turnout type and test cases based on the low-frequency code information; executing the test cases to obtain test results; the test cases include: executing the movement authorization length at the location of the departure signal; receiving no-code / HU low-frequency code sent by the track circuit in the forward turnout area; receiving HU low-frequency code sent by the track circuit within the station; determining whether to reopen the departure signal; checking the onboard equipment's DMI to determine whether the onboard train control system is in human control priority mode, and obtaining the test results. This invention achieves testing of the function of maintaining human control priority mode for lateral entry trains, ensuring the completeness of test coverage and effectively improving test efficiency.

The present invention belongs to the field of wireless communication technology, and specifically relates to a method, device, and electronic device for identifying a preamble pattern. The method first receives a baseband sampling signal, and when it is determined that a valid signal has arrived, performs a cross-correlation calculation on the symbol sequence corresponding to the baseband sampling signal and the local preamble sequence corresponding to a set time-frequency code; then, a delayed autocorrelation calculation is performed on the obtained cross-correlation calculation result and its energy value is calculated; if the maximum value of the energy value is greater than a preset peak threshold value, the preamble pattern corresponding to the set time-frequency code is determined to be the correct preamble pattern. The method only needs to perform a scanning process half the total number of time-frequency codes at most to find the correct preamble pattern, and has high recognition efficiency. Especially in the case of low signal-to-noise ratio and large frequency deviation, the method has high accuracy in time-frequency code detection and recognition, low delay overhead, and does not affect the speed at which the device joins the micro-network. It has low implementation complexity, low power consumption, and strong noise and frequency deviation resistance.

The application belongs to the technical field of ground penetrating radar, and provides a ground penetrating radar control method, device, equipment and storage medium, wherein the method comprises: generating a frequency sequence group matrix meeting preset requirements of a ground penetrating radar by using a chaotic mapping, optimizing the frequency sequence group matrix according to a preset genetic algorithm, obtaining an orthogonal discrete frequency coding transmission waveform set, based on the orthogonal discrete frequency coding transmission waveform set, calling a double-channel narrowband, wideband transceiver and a heterogeneous system-level chip of the ground penetrating radar to transmit a waveform to the ground and receive a reflected waveform, analyzing and processing the reflected waveform, obtaining a ground penetrating result, so as to improve work efficiency, meet high-speed operation detection requirements, improve detection accuracy of the radar, have a unique advantage for spectrum analysis and interference suppression, realize a balance between detection depth and resolution, and do not need complex signal processing technology.

The present invention provides a method and device for feedback of beam information and configuration information, wherein the method comprises: a receiving end receives a reference signal sent by a transmitting end, wherein the reference signal is carried on one or more beams, or each reference signal group is carried on the same beam, and the reference signal group is a reference signal group obtained by dividing the reference signal according to time-frequency code resources; the receiving end obtains a beam sequence number and channel state information according to the reference signal; the receiving end sends a set including the beam sequence number and channel state information to the transmitting end. Therefore, the technical solution of the present invention solves the problem that the receiving end cannot provide feedback on the correlation characteristics between beams, and the transmitting end cannot perform accurate and flexible data transmission according to the correlation characteristics of the receiving end, thereby reducing the diversity and multiplexing gain of the system, and improves the effect of the diversity and multiplexing gain of the system.

The application belongs to but is not limited to the technical field of log data, and discloses a log template extraction method and system based on fixed writing mode mining and a reinforcement method. The method comprises the following steps: performing structural entity replacement preprocessing on original log text, realizing timestamp standardization and special character standardization; performing normalized coding on the preprocessing result, and converting a character stream into a structural semantic coding sequence; performing horizontal fixed writing mode identification on a single log based on a greedy strategy, and extracting a high-frequency coding sequence; performing extended sequence mining in a streaming log based on a light-heavy separation strategy, and realizing cross-log vertical mode reinforcement; and fusing the horizontal and vertical modes and completing template generation and deduplication based on similarity. The method uniformly maps multiple source heterogeneous logs to a coding sequence space, does not need to preset rules, and has self-adaptive template extraction capability.

The application discloses a long-baseline transceiver-displaced multi-radar signal space-frequency code cooperative anti-jamming method, which comprises the following steps: firstly, according to the identification mechanism of the jammer to the intercepted signal and the interference generation mechanism, the space-frequency code domain cooperative anti-jamming strategy is researched; according to the anti-jamming strategy, the narrow-band detection signal model, the wide-band cover signal model and the optimization problem model are established; the optimized signal is obtained by solving the optimization problem; each station transmits the optimized signal; finally, the receiving station utilizes the matched filter to process the radar receiving echo signal. The method considers the dual functions of cover and decoy, that is, even if the interference energy is large, the jammer generates the parameter error interference signal through the deception of the decoy signal, the interference energy received by the detection signal is greatly reduced, the signal form is more complex, the signal recognition of the countermeasure jammer is more difficult, and the anti-jamming performance of the radar system is improved.

The invention provides a magnetic resonance imaging method, a magnetic resonance scanning control method and a magnetic resonance scanning control system. The magnetic resonance imaging method comprises a single sampling step: applying a radio frequency pulse to a scanning object; alternately applying a plurality of forward frequency coding magnetic field gradients and reverse frequency coding magnetic field gradients along with time in a preset time period in a frequency coding direction so as to determine a plurality of echo time points; applying a first phase coding magnetic field gradient in the same preset time period in the phase coding direction; acquiring K space data of the echo time point corresponding to each echo time point; circulating the single sampling step for multiple times to obtain multiple pieces of K space data corresponding to each echo time point; and according to the multiple pieces of K space data acquired at the same echo time point, generating an echo image corresponding to each echo time point. According to the invention, a plurality of adjacent echo time images are utilized, zero deformation can be achieved in principle, the microstructure detection sensitivity of diffusion imaging is improved, and the application range of the microstructure detection is widened.

The invention provides a binary array space-time-frequency code communication anti-interference method based on intelligent sensing decision, which comprises the following steps of: monitoring and judging enemy interference signals by adopting a frequency spectrum sensing technology to obtain related attribute parameters of the enemy interference signals, and intelligently deciding an own communication mode according to differential characteristics of different interference signals, so that the anti-interference performance of the enemy interference signals is improved. And a binary array space-time-frequency code combined anti-interference technology is adopted, so that the communication anti-interference capability under various interference scenes including full-band ultra-wideband interference is improved. According to the invention, the survivability of the communication system in a complex electromagnetic interference environment is improved. A control strategy of interference perception and intelligent decision is introduced, and a space, time, frequency and code combined anti-interference method is adopted in a targeted manner according to differential characteristics of interference signals, so that the system is more intelligent and robust in signal receiving and processing, and the reliability of the system is enhanced.

The invention provides an ocean flow field reconstruction method based on multi-modal hybrid filtering and latent code modulation, and relates to the technical field of ocean dynamics analysis, and the method comprises the steps: carrying out the data preprocessing, constructing a space-time sample index, and obtaining a space sampling point coordinate; carrying out context embedding, carrying out mixed frequency coding, then carrying out multiplicative interaction and hierarchical condition modulation to form frequency selective feature representation, and carrying out deep residual stabilization to obtain implicit features of a current residual layer; the operation of the multiple residual layers is repeated until final implicit features are obtained; and generating a reconstructed flow field through coordinate-by-coordinate linear projection based on the final implicit features. According to the invention, tunable multi-scale spectrum expression is formed through mixed frequency coding. And large-scale flow state characteristics and environment background information are represented through hierarchical condition modulation based on context embedding. A multiplicative conditional modulation mechanism is constructed to strengthen high-frequency response, and layer normalization, learnable layer scaling and a random depth regularization mechanism are introduced in a deep feature propagation stage to carry out deep residual stabilization.

The invention relates to the technical field of image compression, coding and decoding, and provides an image coding method, device and equipment based on dynamic partitioning and a medium, the method comprises the following steps: obtaining a to-be-coded image, carrying out frequency domain processing on the to-be-coded image, and determining a high-frequency sub-band and a low-frequency sub-band of the to-be-coded image; respectively and dynamically partitioning the image areas corresponding to the high-frequency sub-band and the low-frequency sub-band into a plurality of sub-image blocks with different sizes; and generating a high-frequency code stream for each sub-image block of the high-frequency sub-band by using a Range-ANS entropy coding technology, generating a low-frequency code stream for each sub-image block of the low-frequency sub-band by using an adaptive Huffman entropy coding technology, and combining the high-frequency code stream and the low-frequency code stream into a coding code stream of the to-be-coded image. The method provided by the invention is particularly suitable for application scenes such as high-resolution video processing, medical image transmission and storage and rapid compression of satellite remote sensing data, and the coding efficiency can be remarkably improved on the premise of keeping high-quality image restoration.

The invention discloses a space-time-frequency code hybrid multiple access method based on space-based Internet of Things user distribution condition, which relates to the field of satellite communication and comprises the following steps: acquiring a running orbit and a sub-satellite point trajectory of a satellite; predicting the number, the distribution condition and the message service volume of users in a beam coverage area at the satellite top crossing moment; dividing the beam area into a plurality of sub-beam areas, and pre-allocating frequencies and time slots of the sub-beam areas; dividing variable sub-regions in the sub-beam regions, and determining allocated frequencies and time slots; setting a frequency use threshold upper limit and a frequency use threshold lower limit for each sub-beam area; and adjusting the frequency allocated to the sub-beam area according to the frequency use condition of the sub-beam area, providing an access channel for the user in the sub-beam area by using code division multiple access for the sub-beam area of which the frequency use condition exceeds the upper limit, and setting a special spreading code sequence for the user with high priority so as to preferentially de-spread. The frequency resource utilization rate can be improved, and the user access number of the satellite is increased.

The invention discloses a target detection feature enhancement method based on space-frequency cooperative coding, and belongs to the field of computer vision. Firstly, an image to be detected is sent to a target detection network, a spatial domain feature map is extracted, preliminary feature extraction is performed through a convolutional layer, and the feature map is projected to two parallel space-frequency coding branches A and B through channel division; then, modeling and reconstruction of a wavelet frequency domain are carried out on the branch A, and wavelet enhancement path output is obtained; carrying out Fourier frequency domain modeling and reconstruction on the branch B to obtain Fourier enhancement path output; and finally, performing weighted fusion on the feature map, wavelet enhancement path output and Fourier enhancement path output to obtain an enhanced feature Z, inputting the enhanced feature Z into a subsequent detection head of the target detection network, and completing end-to-end training. According to the method, combined modeling of target structure details and semantic contexts is realized by fusing spatial domain and frequency domain information, so that the detection performance and robustness of the model in a complex degradation scene are remarkably improved.

A system and method for time-frequency coding for interference mitigation of sensors is presented that includes generating and transmitting, from a vehicle, a first chirp signal by a first sensor, in a first time-channel and in a first frequency-channel. The method may also include generating and transmitting, a second chirp signal by a second sensor, in a second time-channel and in the first frequency-channel and the receiving, by the first sensor, a first reflection signal from objects from the first chirp signal. In addition, there may be a receiving, by the second sensor, a second reflection signal from objects from the second chirp signal. In addition, the first time-channel is orthogonal to the second time-channel, and the transmitting of the second chirp signal is offset in time from the transmitting of the first chirp signal by an amount less than a duration of the first chirp signal.