259 results about "Multipath interference" patented technology

The invention relates to the technical field of learning methods, in particular to an OPGW heterogeneous detection method based on AI interference elimination, which comprises the following steps: acquiring a vibration signal segment, dividing mutation fragments, arranging channel sequence, comparing direction extension, extracting a direction change homing path segment, analyzing an offset trend positioning response area, and extracting fluctuation trend verification interruption. And combining state feature merging numbers, identifying a jump sequence and analyzing a switching relation, and obtaining disturbance boundary features. According to the method, a path chain is constructed through sudden change signal position division and a channel response sequence, a disturbance propagation starting point and an extension direction can be subjected to structured expression, a path segment corresponding to continuous direction change supports limitation of a response interval, a fluctuation trend and direction offset are combined to form segmented reference, and identification of characteristics of boundary evolution along with time is assisted; the hopping sequence in the tail end signal is used for restoring the disturbance boundary and enhancing the trajectory separation and feature retention capability of the multipath interference behavior in the differentiated environment.

The invention relates to a space-ground integrated Beidou high-precision positioning method applied to urban canyons, and belongs to the technical field of navigation positioning. The method comprises the following steps: deploying a pseudo satellite base station, calibrating coordinates of the base station through carrier phase difference, and monitoring the number of Beidou visible satellites; a master pseudo-satellite is determined, timestamps and ephemeris data are broadcasted to slave pseudo-satellites through Beidou short messages, and the slave pseudo-satellites are combined with bidirectional ranging data to correct a local clock to realize high-precision synchronization; receiving Beidou and pseudo-satellite signals by a user terminal, screening effective observation values through a shielding judgment mechanism, substituting the effective observation values into a non-difference observation equation in combination with pseudo-satellite reference difference data, and resolving a fusion result through an elastic coupling mode; and finally, multi-path interference is identified by using pseudo-satellite double antennas, and historical data is called to construct an error model to correct a fusion result. The space-ground integrated positioning of Beidou and pseudo satellites in an urban canyon scene is realized, the centimeter-level positioning precision is stably output, and the high-precision positioning requirements of urban traffic, surveying and mapping and the like are met.

The invention discloses a high-feature-resolution underwater weak target parameter estimation method based on NOMP, and the method comprises the steps: obtaining a receiving array signal, carrying out the preprocessing of the receiving array signal, carrying out the azimuth angle estimation through employing a conventional beam forming algorithm, and extracting a beam output signal in a main target direction; rough search is carried out on discrete time delay and Doppler factor grids, initial parameters of a current most significant path are estimated, continuous optimization is carried out through a Newton iteration method, and optimized path parameters are obtained; constructing a continuous path echo signal according to the received signal, deducting the contribution of the current path to the received signal from the received signal, updating a residual signal, and continuously searching the next path by taking the residual signal as a new input signal until an iteration termination condition is met; and outputting parameter estimation results of all paths. According to the method, high-precision and high-resolution extraction of weak target parameters can be realized in an environment with a low signal-to-noise ratio and remarkable underwater multipath interference.

The invention provides an underwater positioning system combining sound ray propagation modeling and multipath interference suppression, which relates to the technical field of marine equipment and comprises a self-adaptive underwater sound sensing and environment cognition module, an environment self-adaptive sound ray propagation modeling module, a multipath suppression and direct wave extraction module and a multi-dimensional information fusion and self-adaptive positioning calculation module. The self-adaptive underwater sound sensing and environment cognition module is used for realizing multi-mode sensing and real-time environment feature recognition of underwater sound signals, and the environment self-adaptive sound ray propagation modeling module is used for constructing a dynamically updated sound wave propagation model and providing a propagation path and time constraint for positioning calculation; the multi-path suppression and direct wave extraction module is used for carrying out multi-path signal separation and extracting direct wave features with confidence marks, and the multi-dimensional information fusion and self-adaptive positioning calculation module is used for completing high-precision positioning calculation; according to the system, deep fusion of an environment model and signal processing can be realized, and the positioning precision and robustness of the underwater vehicle in a complex underwater sound environment are remarkably improved.

The invention relates to the technical field of equipment positioning, and discloses a multi-mode positioning method and system based on intelligent wearable equipment, and the method comprises the steps: receiving a Beidou satellite signal and a GPS satellite signal, and executing the sparse channel estimation, and obtaining a channel parameter; identifying and suppressing multipath interference according to the channel parameter to obtain a purified signal; separating the purification signal into Beidou observation data and GPS observation data, and carrying out cross correction calculation to obtain position information; and performing channel state prediction based on the position information and the channel parameters, and compensating positioning calculation at the next moment to obtain a target positioning result and a communication transmission scheme. According to the invention, the complementary advantages of two sets of Beidou and GPS systems are fully utilized, the GPS clock error offset is corrected by using the time service precision of Beidou, the positioning precision of the intelligent wearable device is improved, and the power consumption is reduced.

The invention discloses a data reading method and system based on an RFID reader-writer, particularly relates to the technical field of radio frequency identification data acquisition, and is used for solving the problem that the communication reliability of an existing RFID system is reduced due to carrier frequency deviation and multipath interference in a high-speed mobile environment. A phase change characteristic and an error rate index are obtained through double-antenna receiving signal analysis, when the error rate exceeds a limit, spatial correlation and error rate distribution difference are jointly analyzed to determine a multipath interference level, and meanwhile, a relative motion state is detected and judged through a phase track curvature characteristic. And dynamically selecting an optimal modulation coding mode to read data again according to the calculated motion speed estimated value and the interference level, thereby realizing the optimal balance between the communication rate and the reliability in the mobile environment.

The invention provides an underwater positioning system based on effective sound velocity compensation and multipath equalization, which relates to the technical field of marine equipment and comprises an environment sensing and modeling module, a signal propagation characteristic analysis module, an intelligent signal processing and distance measuring module and a fusion positioning and quality evaluation module. The environment sensing and modeling module is used for constructing a dynamic three-dimensional sound velocity field and evaluating the reliability of the environment, the signal propagation characteristic analysis module is used for establishing a multi-path propagation model and extracting path characteristic parameters, and the intelligent signal processing and distance measuring module is used for suppressing multi-path interference and realizing high-precision distance measuring calculation. The fusion positioning and quality evaluation module is used for multi-source information fusion positioning and forming a quality feedback closed loop; the system can effectively cope with sound velocity temporal and spatial change and multipath interference in a complex marine environment, remarkably improves the precision, stability and robustness of underwater positioning of the underwater vehicle, and is suitable for the fields of deep sea detection, ocean engineering and the like.

The invention belongs to the technical field of wireless communication, and discloses a CNN-Transform direction estimation method based on covariance-unitary matrix input, and the method comprises the following steps: generating received signal sample data of different incident angles; calculating a covariance matrix for a received signal sample, performing singular value decomposition, extracting real parts and imaginary parts of the covariance matrix and a unitary matrix, and constructing a four-channel two-dimensional real number tensor as input; extracting local spatial features and coherence structures through CNN; serializing the feature map and adding a position code; a Transform encoder module is input, and global spatial dependence is modeled; carrying out average pooling and full-connection classification on the output to realize direction angle prediction; and training is carried out by adopting cross entropy loss, an AdamW optimizer and a cosine annealing learning rate scheduler. According to the method, local and global features are fused, and the method has high precision, strong robustness and excellent generalization ability in complex environments of low signal-to-noise ratio, multipath interference and the like.

The invention provides a GIS insulation defect evaluation method and device and electronic equipment, and relates to the field of data processing. According to the method, a cross-modal synchronous data stream formed by an ultrahigh frequency sensor and a mechanical vibration sensor on a GIS (Geographic Information System) is obtained, event slicing is firstly carried out, multi-dimensional features are extracted, and candidate events are screened in combination with a sparse labeling library; and generating a propagation time delay window and a path priority table by using a three-dimensional geometric model, completing cross-modal pairing and time registration, outputting a registration result, performing array manifold sparse reconstruction separation, and eliminating multipath interference to obtain purification components. And constructing a cross-modal event chain graph based on the purification components, executing spatial positioning and physical quantity inversion under the constraint of the chain graph, and finally generating a defect evaluation report in combination with a historical labeling result, thereby realizing high-precision detection and evaluation of GIS insulation defects. By implementing the technical scheme provided by the invention, the accuracy of insulation defect evaluation can be improved.

The invention relates to the technical field of communication, and discloses a wireless signal coverage enhancement system and method based on reinforcement learning, and the method comprises the following steps: fusing multi-source perception data of a laser radar, a camera and the like, extracting a terminal motion state and environment obstacle information in real time, calculating a relative motion parameter and collision time, and carrying out the real-time detection of the collision time; the method comprises the following steps: estimating a threat level according to the obstacle size and distance, outputting a quantitative threat index and a potential high-risk target, identifying an effective reflecting surface from point cloud data, constructing a time-varying diffraction topological graph according to the dynamic obstacle position, and predicting signal loss of each path by using a graph neural network. According to the method, the optimal diffraction path is predicted by sensing the motion trail of the high-speed dynamic obstacle in real time in combination with environmental electromagnetic characteristics, the beam forming and power strategy is dynamically optimized, the influence of multipath interference and penetration loss on the signal quality is suppressed, and the interruption recovery time can be shortened and the positioning precision and the communication reliability can be improved in a shielding scene.

The invention discloses a millimeter wave barrier gate radar multipath interference suppression method and device, and belongs to the field of millimeter wave radar signal processing. The method comprises the following steps: S1, generating an RD image by an echo signal, and executing 2D-CFAR detection to obtain a candidate target unit; s2, eliminating ground reflection (GB) through an RD domain multipath sensitive area mask (MVZ); s3, converting the candidate target unit into a Cartesian coordinate system point cloud; s4, through point cloud domain mirror symmetry verification, removing a pole side mirror image (PSR); s5, clustering the reserved point cloud to obtain a target cluster; s6, through vehicle contour modeling, constructing a rear suppression area to reject vehicle-brake box multiple reflections (VBR); and S7, outputting effective target information after tracking processing. The device comprises a radar radio frequency front end, a signal processing unit, a point cloud post-processing unit, a tracking and control unit and an embedded processing platform. Through a three-layer cooperative inhibition mechanism, three types of main multipath interferences of a barrier gate scene are comprehensively covered, the detection accuracy is improved, static targets are prevented from being mistakenly eliminated, the engineering practicability is high, and safe and reliable barrier gate control can be ensured.

The invention relates to the technical field of satellite navigation and intelligent positioning, and discloses an indoor positioning method and system based on Beidou double-frequency signals, and the method comprises the steps: receiving Beidou B1I and B1C double-frequency signals through adaptive signal enhancement and preprocessing; the double-frequency differential carrier phase extraction technology is adopted to form ionosphere-independent combined observed quantity, and ionosphere delay errors are eliminated. Multipath interference is identified and suppressed through a multipath suppression method based on statistical characteristics, and an extended Kalman filtering algorithm is adopted to fuse Beidou double-frequency observed quantity and IMU inertial data to realize multi-sensor information fusion positioning; according to the method, a soft constraint condition is established by utilizing geometric features of a building to optimize a positioning result, a multi-dimensional precision evaluation model is established to predict the positioning precision, and the result is adaptively output, so that sub-meter positioning precision and millisecond response time can be realized in a complex indoor environment, and an effective solution is provided for an indoor positioning technology.

The invention discloses a gesture recognition method and system based on an active acoustic sensing field, and the method comprises the steps: transmitting a frequency modulation continuous wave through a loudspeaker on head-mounted equipment, and receiving an echo signal reflected by the hand of a wearer through a microphone on the head-mounted equipment; performing frequency mixing, low-pass filtering and analog-to-digital conversion on the echo signal to obtain a digital baseband signal; performing range correction and noise reduction processing on the digital baseband signal to obtain a hand echo signal; inputting a hand echo signal into the multi-scale time sequence encoder, and capturing long time sequence dependence to obtain multi-scale spatial-temporal characteristics; performing trajectory tracking on the multi-scale spatial-temporal features by the hand key point regression branches to obtain hand key point features; inputting the hand key point features and the multi-scale spatial-temporal features into the gesture recognition branch to obtain a gesture recognition result; according to the method, multipath interference and spatial fuzziness in the acoustic sensing process can be overcome, and high-precision and fine-grained gesture recognition is realized.

The invention belongs to the technical field of crown blocks, and provides a crown block real-time communication implementation method and system in an interference environment, electronic equipment and a storage medium, and the method comprises the steps of terminal control instruction execution, communication transmitting frequency band determination, state data packaging, beam direction adjustment, frequency hopping anti-interference analysis, strategy updating and abnormal emergency processing. Through a dynamic optimization mechanism of a frequency hopping communication strategy and a low-interference frequency hopping strategy prediction model, a current frequency band strategy is optimized in real time according to environment information and communication quality feedback, and the interference resistance of a communication frequency band is optimized; through a beam adjustment strategy and EOE protocol packaging, the signal strength is enhanced, signal attenuation and multipath interference are reduced, and the real-time performance of data transmission is improved.

Disclosed in the present invention are a wide-angle scanning imaging device, method and system. The device comprises a sonar probe and a device body. The sonar probe comprises an acoustic array and a transceiving processing module. The acoustic array comprises a transmitting array and a receiving array. The transmitting array comprises a group of transmitting transducers. Maximum response axes of the transmitting transducers are distributed in the vertical direction according to preset tilt angles, and a plurality of transmitted beams of the transmitting transducers form wide-angle coverage in the vertical direction. The receiving array performs resolution in the horizontal direction by means of beamforming, and vertical orientations of echoes are estimated by means of double-array output phase differences. The acoustic array performs rotational motion along the central axis of the device body. The transmitting array transmits broadband orthogonal pulses according to a preset period, the receiving array receives echo signals, and the transceiving processing module processes the echo signals according to the central frequency of the transmitted pulses of the transmitting array to obtain an underwater target imaging result. The present invention reduces the impact of underwater multipath interference and the like on phase estimation and improves the 3D imaging quality.

A Quantum Transceiver Antenna (QTA) is described which is a scalable, thin-film, bi-synchronous, multifrequency resonance antenna, made up of a layered matrix of antenna pixels of uniform size and shape, with voids and nulls in its pattern. On the QTA, electromagnetic signals gain coherence as toroidal geometries, that function as tunable, electromagnetic lenses, to simultaneously resolve and concentrate gain in the full spectrum of radio frequency signals. QTA transceives both particles and waves, and operates using quantum principles, including quantum tunneling whereby solid materials appear invisible, enabling non-line of sight communications, imaging, detection, Q-Tricity, immunity to multipath interference, and ground planes. One QTA replaces disparate antennas in a cell phone / electronic device and operates wirelessly with space-based platforms and terrestrial networks, plug and play, with low impedance, less power, at magnitudes of gain only possible using quantum principles. QTA is frequency dynamic providing mesh networks, IOT, Edge, AI connectivity, and emergency response interoperability solutions.

The invention relates to the technical field of semiconductor radio frequency signal processing, and discloses a narrowband signal receiving system and method, and the system comprises a coarse frequency offset value capturing module, a carrier phase locking module, a digital domain carrier tracking module, a timing synchronization and multipath correction module, and a vector amplitude phase correction and equalization module. In the prior art, the technical problems of lock losing, judgment errors and high bit error rate caused by serious multipath interference and frequency offset drifting of narrow-band signals are difficult to solve in complex environments with multipath effect and high frequency offset, such as urban canyons, basements and warehouses. According to the invention, by introducing analog phase locking, digital fine tuning, dual-correlation symbol synchronization based on multi-path sensing and vector amplitude-phase combined compensation overall architecture with cooperation of analog and digital, the problems of synchronization failure and demodulation performance reduction caused by multi-path distortion in the prior art are avoided; and the sensitivity and the overall reliability of radio frequency signal receiving are remarkably improved.

The invention discloses an anti-multipath interference UWB radar signal denoising and positioning enhancement method and system, and the method comprises the steps: deploying a plurality of groups of UWB radar equipment, collecting original signals in a multipath interference scene, marking the original signals, and constructing a UWB radar signal data set containing multipath interference features, target features and marking information; preprocessing the original signal and extracting multi-domain features; a deep learning model containing a denoising model and a positioning enhancement model is constructed, and joint training is carried out through a joint loss function; training the model by adopting a training strategy of dynamic regularization and a self-adaptive learning rate; and finally deploying equipment acquisition signals, inputting the signals into the trained system for processing, and outputting a positioning result. The method can effectively suppress multipath interference, improves the UWB radar positioning precision and generalization capability, and is suitable for indoor navigation, automatic driving and other scenes.

The invention discloses a low-power-consumption adaptive antenna gain control device for a navigation system, and belongs to the technical field of navigation communication. Comprising an adjustable LNA array, a signal quality monitoring module and an MCU control unit. The adjustable LNA array is used for receiving a satellite signal and dynamically adjusting gain according to a control signal output by the MCU control unit; the signal quality monitoring module integrates a power detector and a signal-to-noise ratio analyzer, and is used for collecting the power, the signal-to-noise ratio and the multipath interference intensity of an input signal in real time, and generating a state vector S based on the collected parameters; and the MCU control unit is used for executing an adaptive gain control algorithm, calculating an optimal gain value based on the state vector S, and dynamically adjusting the gain configuration of the LNA array. Through the low-power-consumption LNA array and a self-adaptive gain control algorithm, high-precision signal receiving of the Beidou / GNSS terminal in a complex environment is realized, power consumption is remarkably reduced, and positioning reliability is improved.

The invention discloses a high-precision indoor and outdoor positioning method based on WiFi FTM distance estimation. The method comprises the following steps: step 1, data preprocessing and coarse correction; step 2, modeling an error system; step 3, constructing a regression model and performing multipath compensation; and step 4, quality control optimization: on the basis of the distance observation value after multipath compensation, new feature engineering and target variables are reconstructed based on new observation data. According to the method, dynamic error compensation and quality control based on machine learning are provided, the problems that in the prior art, multi-path interference errors are difficult to model, the positioning precision is low, and the environmental adaptability is poor are solved, and the precision, usability, reliability and robustness of WiFi FTM indoor and outdoor scene positioning are improved.

The invention discloses a direction of arrival estimation method based on a residual network. A space encoder and an improved residual network cascade module are included. According to the system, complex signals received by an antenna array element are used as input, a covariance matrix is extracted, and a multi-channel characteristic pattern is constructed. Direction-of-arrival coarse estimation is carried out through space encoder partition, and further direction-of-arrival fine estimation is carried out through an improved residual network. Through reasonable combination of the deep neural network and the residual network, high estimation precision and operation speed can still be maintained in complex scenes of low signal-to-noise ratio, small signal source angle interval, multipath interference and the like. Compared with the traditional direction of arrival estimation method, the method provided by the invention has a remarkable advantage in the direction of arrival estimation precision under the complex test conditions of low signal-to-noise ratio and the like. Meanwhile, on the premise that high precision is kept, the method has the higher operation speed, and good real-time performance and engineering application prospects are embodied.

The invention discloses a squint synthetic aperture sonar imaging method based on a dynamic slant-range space-variant model, and relates to the technical field of synthetic aperture sonar imaging, and the method comprises the steps: constructing a dynamic slant-range model; inputting the converted data into the dynamic oblique variation model to obtain a residual space-variant distance bending amount, and compensating the space-variant distance bending amount by using a first filter; according to the dynamic slope distance model, expanding the azimuth time offset into an azimuth frequency modulation factor; based on the azimuth frequency modulation factor and the azimuth time offset, designing a second filter by using an improved extended nonlinear frequency modulation scaling algorithm, and filtering the corrected data by using the second filter; and carrying out Fourier transform on the filtered data, compressing the transformed data by using a third filter, and then carrying out inverse Fourier transform to obtain a focused synthetic aperture sonar image. According to the invention, the imaging performance and stability of the imaging algorithm in a low signal-to-noise ratio and strong multipath interference environment can be improved.

The invention discloses a multi-channel frequency modulation signal real-time monitoring system which comprises at least one monitoring node and a remote cloud platform. The monitoring nodes simultaneously receive multiple paths of frequency modulation signals through the multi-channel radio frequency receiving unit, the signal processing unit demodulates and detects multiple quality parameters such as field intensity, signal-to-noise ratio, frequency offset and multipath interference, the main control unit generates alarm information, and finally the alarm information is uploaded to the cloud platform through the communication unit integrated with 4G / 5G and Wi-Fi. And the cloud platform is responsible for storing and analyzing data and pushing alarms and information display to the authorized user terminal. According to the invention, a multi-core DSP parallel processing architecture, dual-path power supply and battery redundancy power supply and multi-parameter association intelligent alarm logic are adopted, cloud networking management is realized, and the problems of few monitoring channels, low efficiency, insufficient intelligent degree and difficult remote operation and maintenance in the prior art are solved. Therefore, efficient, reliable and intelligent remote monitoring of multi-channel FM signals is realized.

The invention relates to the technical field of radar signal processing, and discloses an anti-multipath interference vehicle-mounted millimeter wave radar signal processing method, and the method comprises the steps: obtaining a radar echo signal, and decomposing the radar echo signal into a plurality of overlapped sub-band signals in a frequency domain; constructing a static environment Doppler manifold curved surface by using self-vehicle motion data, and calculating a theoretical phase evolution model according to the static environment Doppler manifold curved surface; extracting an actual measurement phase difference between the sub-bands, and carrying out coherent accumulation on the actual measurement phase difference and the theoretical model to generate a manifold consistency coherence coefficient; direction-of-arrival estimation is carried out on each sub-band signal, and the spatial spectrum drift statistical dispersion of an angle estimation value is calculated; and generating a target multipath confidence score according to the manifold consistency coherence coefficient and the spatial spectrum drift statistical dispersion, and executing a suppression decision on a radar detection target. According to the invention, by introducing a kinematics physical constraint and broadband space stability detection mechanism, false targets generated by a multipath effect are effectively identified and eliminated, and the environmental perception precision and robustness of the vehicle-mounted radar are improved.

The invention provides an underwater robot attitude stability monitoring method based on data processing, and the method comprises the steps: collecting the sensor data of an underwater robot, carrying out the filtering preprocessing and frequency domain analysis, obtaining a signal spectrum feature and an amplitude change rule, recognizing the multipath effect interference and pressure field fluctuation in a complex seabed environment, recognizing an interference signal, and carrying out the detection of the attitude stability of the underwater robot. Analyzing a sensor data quality change trend; the method comprises the following steps: performing preliminary window configuration, monitoring terrain reflection signal intensity change in real time, if the intensity exceeds a preset threshold range, dynamically adjusting a length parameter and an overlapping rate of a feature extraction window, and performing optimization calculation in combination with an initial parameter model to obtain an optimized window length parameter; and according to the optimized window length parameters, key abnormal features in the attitude data are extracted, a feature vector at the current moment is constructed, the matching degree of the feature vector and historical data is analyzed, and a preliminary judgment result of an abnormal state is determined through similarity calculation and threshold comparison.

The utility model belongs to the field of automobile radio testing, and discloses a bottom surface workbench of a full-radio-wave radio frequency laboratory and the full-radio-wave radio frequency laboratory. The bottom workbench comprises a full-wave-band shielding base station and a full-wave-band testing rotary table. The full-wave-band test rotary table comprises a rotation driving mechanism, a shielding bottom plate structure, a connection supporting structure, a supporting structure and a wave absorbing layer. Wherein the connecting and supporting structure and the supporting structure jointly support a tested object, the surface, close to the tested object, of the supporting structure is used for bearing the tested object, and the connecting and supporting structure is used for supporting the supporting structure and dispersing and transmitting pressure, applied to the supporting structure, of the tested object to the shielding bottom plate structure. According to the bottom surface workbench of the full-radio-wave radio frequency laboratory and the full-radio-wave radio frequency laboratory, it is guaranteed that an object to be tested can be effectively supported, and multi-path interference from the ground can be effectively restrained.

The application discloses a marine buoy multi-source fusion positioning method and system based on a factor graph optimization, which acquires GNSS observation data, IMU measurement data and marine environment auxiliary data; a factor graph containing state nodes, GNSS position factors, IMU pre-integration factors and marine dynamics constraint factors is constructed, and wave and current theories are used to constrain buoy movement; in view of multipath effects, marine surface reflection geometry and marine root mean square wave height are combined to calculate a multipath weighting factor, and a GNSS covariance matrix is adaptively adjusted; according to IMU data, a sea state level is discriminated, and an edge window length and a trigger interval of incremental smoothing solving are adaptively linked and adjusted; through adjacent buoy ranging information, collaborative constraints are constructed, and based on Mahalanobis distance and chi-square distribution threshold value detection, abnormalities are detected and local reconstruction is performed. The application effectively suppresses marine surface multipath interference, slows down the accumulation of calculation errors during signal interruption, and realizes high-availability continuous positioning under limited computing power.

This invention relates to an IMU-assisted online GNSS anomaly detection and reporting method and apparatus. The method involves acquiring GNSS observation data and IMU measurement data and aligning them in time; generating a predicted motion state of the receiver at the current observation epoch based on the IMU measurement data; calculating the predicted GNSS observation value of at least one satellite at the current observation epoch based on the predicted motion state and satellite ephemeris information; constructing a residual sequence based on the predicted GNSS observation value and the corresponding GNSS observation value in the GNSS observation data, performing sliding time window statistics, and determining anomalies based on the statistical results; when an anomaly is determined, generating a time index and a spatial index corresponding to the anomaly, forming a spatial-level interference event, and reporting it. This invention effectively reduces the false alarm rate and missed alarm rate in scenarios involving obstruction, multipath interference, and other interference, exhibits higher sensitivity to observation anomalies caused by moving interference, effectively lowers the implementation threshold at the receiving end, and possesses high engineering application value.

The invention discloses a multipath interference detection method, an optical receiving device, a system and a communication device, and the method comprises the steps: determining sets of error signals of preset levels corresponding to a modulation format employed by an optical transmitting device based on original signals obtained after the conversion of the optical receiving device, and each preset level corresponds to one set; for at least two sets, calculating a mean value feature of the error signals in each set; a first index value characterizing the MPI intensity is calculated based on the mean feature. Therefore, only simple statistical calculation is needed, complex calculation is not needed, sending signals do not need to be changed, calculation resources and storage resources are reduced, and therefore real-time MPI detection which is low in calculation complexity, low in cost and compatible with service signals is achieved.

The invention provides a phase ranging method based on the combination of orthogonal matching pursuit (OMP) and three-point interpolation refinement. The phase ranging method is suitable for a BLE / SLE narrowband wireless communication system. The method comprises the following steps: firstly, constructing a delay-frequency dictionary, obtaining a multi-channel phase vector through bidirectional phase measurement, and carrying out expansion and normalization processing on the multi-channel phase vector; then, using an OMP algorithm to select an atom which is most matched with the measurement phase in a dynamically generated predefined dictionary, and obtaining rough time delay estimation; then, based on the selected atom and the matching amplitude of the two adjacent points, a three-point parabola interpolation formula is adopted to carry out sub-step size refinement on the time delay, and more accurate time delay estimation is obtained; and finally, converting the refined time delay into a distance value. According to the method, multipath interference is effectively suppressed through sparse modeling, a dictionary step size limit value is broken through through an interpolation step, the distance measurement precision is remarkably improved, and the method has good embedded deployment value.