106 results about "Phase distortion" patented technology

The invention relates to the technical field of optical detection, and discloses an object surface three-dimensional topography measurement method based on optical interference, which comprises the following steps: acquiring a mixed time domain interference signal sequence in an axial scanning process; extracting seed pixels and constructing a spatial topology connectivity feature matrix; introducing fractional Fourier transform, and constructing a joint decoupling objective function containing a frequency domain nonlinear phase distortion evaluation index and a time domain physical invariant evaluation index; executing multi-stage optimization for the seed pixels, and locking a global optimal rotation angle; array self-adaptive decoupling is executed in combination with the spatial topology connectivity feature matrix, and an optimal rotation angle matrix is generated; and performing signal decoupling and reconstruction on the mixed signal, and extracting the absolute surface height of each pixel point to generate three-dimensional shape data. According to the invention, through multi-dimensional joint decoupling and spatial prior constraint, the problem of phase decoupling caused by film interference aliasing is solved, and the calculation overhead of a large-pixel array is reduced while the measurement precision is improved.

The invention relates to the technical field of industrial vision, in particular to an automobile part surface defect detection method and system based on machine vision, and the method comprises the steps: firstly loading a CAD three-dimensional model, and rendering an ideal fringe reflection map in a virtual environment; calculating an optical distortion correction matrix by comparing the phase distortion with the phase distortion of an actual initial reflection image, driving a programmable light source to project a compensation pattern, and generating a normalized reflection intensity image; signal object decoupling is achieved through multi-scale wavelet transform, and high-frequency components and low-frequency components are separated; homomorphic filtering is applied to the low-frequency component to construct a homogenized background model, the high-frequency component is reversely corrected, and a high-signal-to-noise-ratio defect signal image is output; generating a coarse segmentation mask by the high-frequency signal through an adaptive local threshold, generating a morphology anomaly mask by the low-frequency signal through Hessian matrix morphological analysis, and fusing to form a collaborative segmentation mask; and extracting multi-dimensional geometric attributes of connected domains in the masks, and inputting the multi-dimensional geometric attributes into a decision tree to realize accurate classification and confidence output of defects.

The invention relates to the technical field of ultrasonic signal processing, in particular to an ultrasonic data processing method and system and electronic equipment, and the method comprises the steps: obtaining an original ultrasonic echo signal, and carrying out the time gain compensation, band-pass filtering and down-sampling preprocessing; extracting dynamic frequency dispersion characteristic parameters based on Coann class time-frequency distribution; constructing a depth self-adaptive phase compensation model, and correcting nonlinear phase distortion segment by segment; hilbert transform is adopted to extract an envelope, and after logarithmic compression and linear mapping are carried out, image reconstruction is completed by utilizing delay summation beam forming and an adaptive contrast enhancement algorithm. According to the method, the imaging definition is improved through cooperation of frequency dispersion modeling and phase correction, and the method has good depth adaptability and image visualization effect and is suitable for high-precision image acquisition requirements in scenes such as medical ultrasonic imaging and industrial nondestructive testing.

The invention relates to the technical field of satellite communication, and discloses an efficient encoding and decoding and distribution transmission method for satellite image data, which comprises the following steps of: acquiring satellite epoch parameters, estimating a downlink channel capacity sequence, decomposing the image data into a basic feature code stream and a background residual code stream, and distributing a transmission priority, and mapping the basic feature code stream to the most significant bit of the modulation symbol, mapping the background residual code stream to the least significant bit of the modulation symbol, and implementing nonlinear displacement stretching on the coordinate of the constellation point where the modulation symbol is located according to the carrier frequency shift change rate. A core semantic bit phase tolerance boundary is expanded by compressing a background data judgment space, high-fidelity transmission of key image features in a severe phase distortion environment is ensured, and the information transparent transmission capacity in a high-dynamic link is improved.

The invention relates to the technical field of light field regulation and control, and discloses a static phase distortion compensation system of a spatial light modulator, which comprises a polarization splitting prism arranged in the light emitting direction of a laser and used for adjusting a light beam emitted by the laser into linearly polarized light in the horizontal direction, the first quarter-wave plate adjusts the linearly polarized light into circularly polarized light and irradiates the circularly polarized light to the spatial light modulator; a second quarter-wave plate arranged in the light emitting direction of the spatial light modulator adjusts an emergent light beam of the spatial light modulator into linearly polarized light, and a linear polarizer performs polarization analysis on the emergent light beam of the second quarter-wave plate; the static phase error of the spatial light modulator is determined through the polarization direction included angle of the incident beam of the first quarter-wave plate and the emergent beam of the second quarter-wave plate, and the polarization direction included angle is determined through the Malus law relation of the incident light intensity and the transmission light intensity of the linear polarizer. The static phase distortion of the spatial light modulator is compensated by using the phase error, and the static phase distortion compensation cost is reduced.

The application relates to the technical field of underwater communication and signal processing, and provides an anti-interference method for underwater power carrier communication, which comprises the following steps: acquiring a power carrier time-frequency signal received by an SRM and synchronously collecting a control instruction stream, wherein the power carrier time-frequency signal is an OFDM signal; determining a state perception weight matrix based on a relay action time window, wherein the relay action time window is determined based on the control instruction stream; determining a joint optimization problem provided with a phase distortion correction operator based on the power carrier time-frequency signal, the state perception weight matrix and a frequency domain confidence matrix in combination with a double-weighted robust principal component analysis algorithm, wherein the frequency domain confidence matrix is determined based on the high-frequency attenuation characteristics of an underwater umbilical cable; and solving the joint optimization problem based on a linearized alternating direction multiplier method to determine a target power carrier signal. The application solves the problem that reliable communication cannot be realized under the double constraints of strong interference and severe phase jitter in the related art.

This invention discloses a method for amplitude and phase distortion correction in ISAR broadband direct sampling receivers. First, an amplitude and phase distortion echo signal model for the ISAR broadband direct sampling receiver is constructed. Matched filtering is applied to the amplitude and phase distortion echo signal at a single scattering point, and a fitness function is constructed based on the matched filtering results. Then, the PSO algorithm is used to iteratively optimize the amplitude and phase distortion coefficient vector of the echo signal at each scattering point, obtaining an estimated vector of amplitude and phase distortion coefficients, thus obtaining the amplitude and phase distortion estimates for the echo signal at each discrete point. Finally, an amplitude and phase compensation factor is calculated based on the estimated amplitude and phase distortion values ​​of the echo signal at the discrete points. This factor is used to correct the amplitude and phase distortion echo signal at each discrete point in real time, obtaining the corrected echo signal at each discrete point. The corrected echo signals at each discrete point are then superimposed to obtain the final corrected echo signal. This method solves the problems of insufficient targeting and easy getting trapped in local optima in high-dimensional solutions, thus improving ISAR imaging performance.

The present disclosure provides a sequential power amplifier that achieves phase distortion compensation using sequential operation. [Solution] The sequential power amplifier according to this disclosure comprises a main amplifier that performs signal amplification at a constant load regardless of the input level, and an auxiliary amplifier that performs signal amplification at high power output when the input level is above a predetermined level, and whose phase distortion characteristics are different from those of the main amplifier. The phase distortion characteristics of the main amplifier are inverse to those of the auxiliary amplifier.

Disclosed in the present invention is a high‑linearity, high‑power GaAs HBT power amplifier having a power detection function, characterized in that: the GaAs HBT power amplifier comprises a radio frequency path, a bias module and a power detection circuit. The radio frequency path is used to perform power amplification on a radio frequency signal, a negative feedback network is used to improve the stability and expand the bandwidth, and second harmonic suppression improves the overall linearity. The bias circuit is used to provide, to a three-stage amplification circuit, a bias voltage that dynamically changes along with an input power, so as to solve the problems of linearity degradation and current instability caused by a self-heating effect in a GaAs HBT transistor under high-power input, thereby mitigating amplitude-amplitude distortion and amplitude-phase distortion of the power amplifier. The power detection circuit is used to output a direct current voltage that is positively correlated with an output power, so as to achieve accurate control of the output power of the power amplifier. By fully integrating negative feedback, dynamic biasing and harmonic suppression techniques, the present invention effectively improves the overall linearity of the amplifier.

The invention discloses an indoor positioning method based on two-dimensional sparse array signals. The method comprises the following steps: firstly, deploying a pair of equipment carrying a commercial Wi-Fi network card (Intel 5300) indoors, and configuring and acquiring channel state information (CSI) under multi-time snapshots in a form of'single transmitting antenna + three receiving antennas'; secondly, inhibiting phase distortion in the CSI data by using a linear fitting preprocessing method; thirdly, partitioning the total CSI data according to time snapshots, and inputting the total CSI data into a two-dimensional sparse iteration covariance estimation algorithm to estimate a multipath signal angle-time delay parameter; and finally, through a clustering algorithm, locking direct path features and completing accurate positioning. According to the method, the number of array elements of the receiving array is virtually expanded by using the subcarriers, the bottleneck of limited physical array elements of commercial Wi-Fi equipment is broken through, the positioning precision is greatly improved, the deployment cost is low, the compatibility is high, and the method is suitable for indoor positioning and other scenes.

The present application relates to quantum key distribution, in particular to a satellite-ground continuous variable quantum key distribution system and method based on deep learning, a signal receiving and branching module receives multiplexed optical signals containing quantum signals and classical reference pulses from a satellite, and separates the quantum signals and classical reference pulses corresponding to a coherent detection and key generation module and an intensity measurement module; the intensity measurement module obtains a two-dimensional intensity distribution image of the classical reference pulses; a deep learning phase estimation module has a pre-trained deep learning model, takes the two-dimensional intensity distribution image as input, and outputs a two-dimensional phase correction value matrix with the same resolution as the input image; a phase modulation module performs real-time phase correction on the locally generated optical wavefront according to the two-dimensional phase correction value matrix to compensate for the phase distortion caused by atmospheric turbulence; the present application can effectively overcome the defect that it is difficult to accurately and real-time correct the phase distortion caused by atmospheric turbulence in the satellite-ground link.

The present invention relates to a signal design technique resistant to phase distortion and may provide a method of a transmitter, the aspect comprising the steps of: modulating a sequence of source bits to be transmitted to a receiver to generate a first block of symbols; inserting at least one pilot into the first symbol block to generate a second symbol block; performing cumulative linear coding on the second symbol block to generate a third symbol block; performing real phase conversion on the third symbol block to generate a first signal converted to a phase value; adding a cyclic prefix (CP) to the first signal to generate a second signal; and wirelessly transmitting the second signal to the receiver.

This invention provides a three-dimensional sonar imaging method based on acoustic orbital angular momentum and Bessel compensation. The method performs initial elevation and azimuth beamforming on multimodal OAM echoes to obtain preliminary three-dimensional sonar imaging results. The elevation angle is extracted and a Bessel compensation factor is obtained to correct signal distortion and suppress sidelobes in the time domain. Secondary beamforming is then performed using modal-dimensional azimuth matching vectors to improve azimuth resolution. Finally, a high-resolution, high-contrast three-dimensional image is output. This invention accurately compensates for amplitude and phase distortion of multimodal OAM echo signals by using a compensation factor obtained based on the target elevation angle and the characteristics of the Bessel function. This significantly reduces signal errors caused by wavefront bending, modal coupling, and non-ideal scattering, restores the orthogonality between different OAM modes, and improves imaging fidelity. This invention effectively compensates for OAM mode propagation and scattering distortion and suppresses modal coupling, making it suitable for various high-precision three-dimensional sonar imaging scenarios.

The invention relates to the technical field of image processing, in particular to a terahertz source focusing device image processing method and system.The method comprises the steps that a stable index graph is generated through differential light intensity and gradient fusion, inter-frame boundary phase trends are compared, pseudo boundaries are screened out, credibility labels are generated, and effective boundary phase distortion, energy density and scattering coefficient characteristics are extracted; phase compensation, wavefront correction, frequency band weight iterative correction and superposition correction are optimized to reconstruct a beam to generate an optimized focusing image. According to the method, multi-dimensional stability index quantification wave beam dynamic characteristics are constructed through light intensity fluctuation standard deviation, change density and gradient fusion, boundaries are accurately screened based on inter-frame phase comparison and trend consistency to improve recognition reliability, and phase distortion, energy density and scattering coefficient mapping model correlation parameters and imaging quality are established. Phase compensation, wavefront correction and frequency band weight iterative correction are optimized in a layered manner to eliminate coupling conflicts, and beams are superposed and reconstructed in real time to enhance the uniformity and sharpness of focal spots and suppress noise.

The invention discloses a virtual power plant gradeability dynamic approval method based on AGC performance indexes, and relates to the technical field of virtual power plant scheduling and power system control. The method comprises the following steps: performing phase-space reconstruction on distributed resources to extract chaotic features and generate a basic climbing feature set; generating a multi-source node power distribution manifold by using an optimal transmission theory; the AGC index is converted into a dynamic repulsion potential field based on a control barrier function, and an optimal response strategy is solved in a manifold through multi-agent reinforcement learning; and calculating the power fluctuation fatigue damage degree by using a rain flow counting method, and dynamically reducing the residual available capacity. The method is used for solving the problems that traditional static approval is low in precision, massive resources respond to phase distortion, AI regulation and control lacks physical security constraints, and scheduling default is caused by the fact that service life attenuation of equipment under the high-frequency frequency modulation working condition cannot be sensed.

The invention discloses a dual-mode millimeter-wave radar channel amplitude-phase distortion compensation method and device and a storage medium, and the method comprises the steps: obtaining a transmitting-receiving control parameter, and carrying out the analysis of the transmitting-receiving control parameter, and obtaining a transmitting waveform parameter and a local oscillator waveform parameter; starting from the low-frequency end of the working bandwidth of the system, adjusting a transmitting waveform parameter and a local oscillator waveform parameter, and generating paired single-tone correction signals as a transmitting pre-driving signal and a local oscillator pre-driving signal respectively; generating an analog intermediate frequency signal according to the transmitting pre-driving signal and the local oscillator pre-driving signal, and extracting a distortion amplitude phase value corresponding to the current frequency point from the analog intermediate frequency signal; controlling the frequency of the paired single-tone correction signals to be gradually increased according to a preset step length, and obtaining distortion amplitude and phase values of a plurality of frequency points; performing interpolation fitting on the distortion amplitude-phase value, and calculating an equalizer coefficient; and step frequency is adjusted and calculation is repeated until all equalizer coefficients are obtained for performing dual-mode millimeter wave radar channel amplitude phase distortion compensation.

The application discloses a kind of underwater target positioning method, system and terminal based on dynamic error suppression, the method includes: the vibration signal of underwater target is obtained by distributed optical fiber acoustic wave sensing technology, the rough position of underwater target is obtained according to vibration signal, according to rough position, first time difference is obtained by sound field propagation phase compensation model, and the first accurate position is obtained by correcting the phase distortion of rough position according to first time difference;Strain data of optical fiber is collected, and the actual curvature radius of sound wave propagation path is obtained using strain data, second time difference is obtained according to actual curvature radius, and the optical cable deformation of first accurate position is corrected according to second time difference, to obtain second accurate position;According to second time difference, dynamic compensation is carried out on sound path difference, to obtain corrected sound path difference, and the final accurate position is obtained according to corrected sound path difference;The real coordinate is obtained by coordinate conversion to final accurate position.The precision of underwater target positioning is significantly improved.

The invention discloses a rotating sound source recognition and positioning method based on a deep convolutional attention neural network, and belongs to the field of rotating sound source recognition, and the method comprises the steps: firstly carrying out the motion compensation and modal expansion of a sound pressure cross-spectrum matrix through a modal decomposition rotating beam forming algorithm, and generating a sound source distribution diagram in a rotating scene; then the sound source distribution map is input into a deep convolution attention neural network model, the model adopts an encoder-decoder structure, a channel and a space attention mechanism are fused, key sound source features are dynamically focused, noise interference is suppressed, and high-precision reconstruction of the sound source distribution map is achieved; and finally, carrying out local maximum value detection on a prediction map output by the network, and extracting a sound source space position. According to the method, the Doppler effect and phase distortion problems in rotating sound source positioning are effectively overcome, and the positioning precision, the anti-noise performance and the calculation efficiency in a complex rotating field are remarkably improved.

The application relates to the technical field of equipment calibration, and discloses a cooperative directional calibration method, a cooperative directional calibration system, electronic equipment and a storage medium, which comprise the following steps: acquiring the circumferential strain distribution data of a drill rod, extracting the amplitude-frequency characteristics of a dominant vibration mode and the phase shift amount of a coupled vibration mode; generating an amplitude compensation coefficient according to the amplitude-frequency characteristics, generating a time-varying phase compensation factor in combination with the phase shift amount, and generating a dynamic vibration compensation parameter based on vibration energy distribution dynamic weighting fusion; based on a pre-trained nonlinear phase distortion compensation model, inputting the dynamic vibration compensation parameter, and outputting a phase-corrected gyroscope angular velocity signal; performing vibration interference frequency band suppression processing on an accelerometer signal, and outputting the processed accelerometer signal; performing iterative optimization on the corrected angular velocity signal and the processed accelerometer signal, and outputting a directional calibration result after filter smoothing processing. The application can realize high-precision cooperative calibration of inertial sensors in a multi-modal mechanical vibration environment.

The application discloses a kind of based on Internet of Things distributed edge computing system and method, belong to edge computing and intelligent sensing technical field, by constructing node level three-domain coupling model, realize the collaborative modeling of original sampling sequence, clock signal and electromagnetic environment disturbance data;Further identify pseudo-synchronous interval and generate phase distortion indicator function, reconstruct the phase of data;On this basis, extract phase collapse entropy gradient parameter and cross-node phase hysteresis loop area parameter, construct topological mapping matrix to depict phase collapse propagation path;Task dynamic decomposition and path avoidance are realized in combination with the topological mapping matrix, and phase distortion compensation is introduced in asynchronous computing process;Finally, output high-confidence state evaluation results through reverse consistency check and fusion;The application can effectively inhibit the influence of phase collapse, improve the accuracy and stability of distributed edge computing.

The invention relates to a glass assembly and a glass product. The glass product comprises a glass body, an antenna housing and an antenna module. The glass body is provided with a mounting hole penetrating through the glass body in the thickness direction. The radome is connected with the glass body and arranged at the mounting hole, the radome is made of a wave-transparent material, and the antenna signal transmittance of the radome is greater than that of the glass body. The antenna module is connected to the inner side surface of the radome. According to the glass assembly and the glass product, the antenna signal transmittance of the antenna housing is greater than the antenna signal transmittance of the glass body, and an almost transparent transmission channel can be provided for 5G antenna signals and radar signals, so that the loss of the antenna signals of the antenna module is extremely low when the antenna signals penetrate through the antenna housing, and the high-quality transmission of the antenna signals is ensured; the insertion loss and phase distortion of 5G antenna signals and radar signals are significantly reduced, and the communication quality, stability and receiving sensitivity of various vehicle-mounted antennas are ensured.

The invention discloses a power frequency voltage measuring method and device and a computer program product, and the method comprises the steps: S1, collecting an analog voltage signal of a measured power frequency power line through a non-contact induction module; s2, amplifying the collected analog voltage signal, and converting the analog voltage signal into a digital voltage signal; s3, filtering the digital voltage signal to extract a power frequency fundamental component, and removing signal noise and non-target signal components; and S4, performing nonlinear fitting on the filtered signal through a pre-constructed nonlinear model to complete amplitude correction, and obtaining a power frequency voltage measurement result. Potential safety hazards of traditional contact type measurement can be avoided, hardware cost is reduced, circuit coupling interference is avoided, filtering linear delay is guaranteed to be free of phase distortion, meanwhile, error propagation is avoided through nonlinear correction, measurement precision and self-checking capacity are improved, and the method is adaptive to different measurement systems and is suitable for power utilization inspection, equipment protection and troubleshooting scenes.

The invention discloses an offshore microwave signal time-frequency joint equalization method, system and device based on a Transform model and a medium, and belongs to the technical field of deep learning models and signal processing, and the method comprises the steps: collecting and preprocessing offshore microwave radio frequency signal data, and obtaining a complex baseband signal sequence; generating a time-frequency spectrum matrix; constructing an auxiliary feature vector sequence; dividing the auxiliary feature vector sequence into time frequency units to form a token sequence; the token sequence is input into an improved Linformer-Transformer model, and a hidden representation sequence is obtained; outputting a combined equalization coefficient vector; carrying out amplitude-phase correction to obtain a balanced complex baseband signal sequence; and obtaining an equalized time-frequency spectrum matrix and a reconstructed complex baseband signal sequence. According to the invention, time-frequency joint equalization of signals is realized, the transmission reliability and signal quality of offshore microwave communication are improved, and the problems of amplitude distortion and phase distortion caused by multipath propagation, frequency selective fading and phase random drift in an offshore microwave channel are effectively solved.

The waveform design and transmission method based on FDA and random code combination belong to the physical layer security transmission technical field of wireless communication.The present application solves the problems of the lack of physical layer waveform diversification characteristics and poor physical layer security performance of the existing method.The receiver of the waveform design based on FDA has the diversification of the amplitude and phase of the signals received at different angles, different distances and different times, and on this basis, the dimension of random code is introduced to increase the waveform degree of freedom and enhance the diversification of the waveform.The amplitude and phase of the signals received by the legal receiver are almost not distorted and do not change with time, while the eavesdropping receivers at other positions will receive different signal waveforms with serious amplitude and phase distortion, and cannot obtain useful information.The present application realizes the physical waveform diversification through the combination of FDA and random code, and enhances the physical layer security performance of communication.The method can be applied to the physical layer security transmission technical field of wireless communication.

The invention discloses an inverse synthetic aperture radar imaging method and system with phase distortion and two-dimensional compression sampling, terminal equipment and a medium, and relates to the technical field of radar imaging. The method comprises the following steps: constructing a sparse recovery model containing phase error correction based on a low-rank and sparsity principle; wherein the sparse recovery model is adapted to an inverse synthetic aperture radar echo signal which is subjected to two-dimensional compression sampling and has phase distortion; and based on a unified alternating direction multiplier method framework, solving the sparse recovery model to complete sparse recovery and phase error correction of the two-dimensional compressed sampling signal, and outputting an inverse synthetic aperture radar image. According to the method, the problems that phase errors are ignored in existing inverse synthetic aperture radar imaging and phase correction fails during down-sampling are solved, a clear image can be generated, and the calculation complexity is reduced.

This application discloses a method and system for compensating power frequency probe measurement data based on frequency response characteristics, relating to the field of data compensation. The method includes: acquiring a power grid time-domain signal; performing real-time parallel filtering on the power grid time-domain signal and completing spectral segmentation of the power grid time-domain signal to obtain a multi-frequency time-domain signal; extracting multi-frequency signal parameters from the multi-frequency time-domain signal and constructing a frequency response distortion vector; iteratively fitting the probe's frequency response transfer function using the frequency response distortion vector as a constraint condition, and completing real-time compensation for amplitude and phase distortion of the power grid time-domain signal to obtain an amplitude and phase compensation signal; extracting the instantaneous values ​​of the conjugate half-wave pairs of the amplitude and phase compensation signal, and performing secondary signal compensation of the amplitude and phase compensation signal based on the instantaneous values ​​of the conjugate half-wave pairs to obtain the target compensation signal. This application can effectively improve the accuracy of power frequency probe measurement data.

The invention relates to an anti-metal interference industrial UWB positioning calibration method, device, equipment and medium, and the method comprises the steps: calculating an inertia prediction error through inertia prediction data and inertia measurement data of an ultra-wideband signal, inputting the positioning prediction data to a transmission state region model, and outputting a corresponding label region non-line-of-sight weight; then, performing weighted summation on the inertial prediction error and the non-line-of-sight weight of the label area, and performing calculation to obtain the non-line-of-sight weight; and finally, when the non-line-of-sight weight is greater than a preset non-line-of-sight threshold, performing non-line-of-sight compensation correction on the ultra-wideband signal through a dynamic attenuation compensation model to obtain an ultra-wideband positioning calibration signal, thereby effectively solving the problem of signal interference caused by a metal obstacle, compensating phase distortion caused by the metal obstacle, and recovering the integrity of the signal.

The application discloses a kind of based on the partial coherence light field generation method and system of multi-core optical fiber, method includes: according to the cross spectral density function of target partial coherence light field determines multiple electric field modes and generates hologram;The phase distortion between the each core of multi-core optical fiber is measured and compensation chart is generated;After the superposition of both as synthetic hologram, the wavefront modulation of incident laser is carried out;Modulated light is coupled into multi-core optical fiber and exports target light field.The corresponding system includes mode and compensation chart generation module, hologram synthesis module, wavefront modulation module and coupling transmission module.The present application realizes system miniaturization and strong environmental adaptability using multi-core optical fiber, by hologram sequence and phase compensation combination, can flexibly generate and transmit multiple partial coherence light with specific spatial coherence structure, solve the problem that prior art is not flexible, difficult to apply in tortuous narrow environment.

This invention discloses a method and system for uplink single-carrier symbol correction in narrowband IoT based on a Costas ring, supporting the narrowband IoT protocol specifications defined in 3GPP Release 13. This invention combines the Costas ring with the characteristics of narrowband IoT uplink, utilizing software-defined radio equipment to acquire uplink single-carrier signals. By reconstructing the Costas ring structure, a nonlinear phase detector and a low-pass filter are jointly designed to form a loop filter with joint gain. A digital frequency synthesis module replaces the traditional voltage-controlled oscillator, dynamically compensating for symbol frequency offset and phase distortion based on the error signal output from the Costas ring, thereby completing the demodulation of the real narrowband RF signal. This invention solves the symbol distortion problem caused by frequency offset, multipath effects, and hardware nonlinearity in narrowband IoT scenarios, and can significantly reduce the communication bit error rate compared to traditional channel estimation schemes.

The invention discloses a cross-water and cross-air holographic projection system and method based on an amplitude-phase decoupling acoustic artificial interface, arbitrary and combined modulation is performed on the amplitude and phase of sound waves, in a cross-medium scene, dual modulation can better compensate energy loss and phase distortion at the interface, and the system and the method have good application prospects. Therefore, more accurate wavefront reconstruction and a sound field mode with higher resolution are realized; according to the acoustic metamaterial unit based on the UV resin skeleton-air channel binary composite material, complete control over the amplitude and phase of transmission sound waves is achieved at the specific frequency; an acoustic artificial interface located at the junction of media is constructed by utilizing a super-structure unit and serves as an acoustic projector, cross-medium projection of a holographic image and cross-medium control of particles are achieved, and a new high-fidelity cross-medium acoustical holography mechanism is constructed.