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142results about How to "Guaranteed estimation accuracy" patented technology
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Online lithium ion battery SOC (state of charge) estimation method based on extended Kalman filter
InactiveCN103529398AEstimates are accurate and reliableReliable convergenceElectrical testingCapacitanceEstimation methods
The invention discloses an online lithium ion battery SOC estimation method based on extended Kalman filter, belongs to the technical field of SOC prediction of a lithium ion battery, and aims to solve the problem that the reliability of the online estimation of a conventional lithium ion battery SOC is low due to influence of initial value selection. The method comprises the steps as follows: a voltage and current relation of a first-order RC (resistance / capacitance) equivalent circuit of a detected lithium ion battery and a voltage and current relation of a second-order RC equivalent circuit are established firstly; a charge-discharge experiment is performed on the detected lithium ion battery to establish a polynomial fitting function of a Kalman filter initial value SOC 0 of the detected lithium ion battery; a covariance P (0) of the Kalman filter initial value SOC 0 and a Kalman filter initial error of the detected lithium ion battery is obtained; and then, battery SOC estimation based on extended Kalman filter is performed, so that the online estimation of the lithium ion battery SOC is realized. The method is used for online estimation of the lithium ion battery SOC.
Owner:HARBIN INST OF TECH
OFDM-MFSK underwater acoustic communication broadband Doppler estimation and compensation method based on sub-carrier energy
ActiveCN107231176AImplement trackingImprove estimation accuracySonic/ultrasonic/infrasonic transmissionFrequency-modulated carrier systemsCommunications systemEstimation methods
The invention discloses an OFDM-MFSK underwater acoustic communication broadband Doppler estimation and compensation method based on sub-carrier energy, and belongs to the field of the underwater communication. The specific content is as follows: a transmitting end inserts a pulse pair signal between a synchronization signal and the data; a receiving end firstly detects the synchronization signal to complete the Doppler initial compensation; the demodulation is performed on each OFDM-MFSK data block in the data in a way of one data block by one data block to estimate the effective sub-carrier position, and the energy sum of all effective sub-carrier is used as the cost function to perform the search according to the given different Doppler factors, thereby acquiring the fine Doppler factor of the current data block to complete the fine compensation of the Doppler; and finally the receiving data is demodulated. By using the method disclosed by the invention, the accurate estimation and compensation of the broadband Doppler in the underwater OFDM-MFSK communication system is effectively realized, and the problem that the traditional Doppler estimation method is bad in stability and low in estimation precision is solved.
Owner:HARBIN ENG UNIV
Kalman filtering based method for estimating roll angle and pitching angle of vehicle
ActiveCN104061899AGuaranteed estimation accuracyMeet application needsAngle measurementIncline measurementAccurate estimationMarine navigation
The invention discloses a Kalman filtering based method for estimating roll angle and pitching angle of a vehicle. Aiming at four-wheel land vehicles, the method establishes a kinematic model conforming to the driving characteristics of the vehicles, and further realizes real-time and accurate estimation of roll angle and pitching angle of the vehicles by a Kalman filtering method. The method provided by the invention is also applicable for estimation of large roll angle and pitching angle, meets application requirements under complicated conditions, and only requires a low cost vehicle sensor. The estimated roll angle and pitching angle information is key parameters for vehicle integrated navigation and positioning.
Owner:SOUTHEAST UNIV
Combined synchronization process and its receiving terminal based on two-dimension short time slippage self-correlation
InactiveCN101321150ASynchronization is reliable and preciseAvoid Spectrum Utilization Efficiency DegradationMulti-frequency code systemsSynchronising arrangementTransport systemSelf correlation
The invention relates to a united synchronized method based on the two-dimensional short sliding self correlation, comprising: firstly, the receiving end processes the two-dimensional short sliding self correlation for the receiving serial; secondly processing the circulated frame synchronization by using the result of the self correlation operation; then, processing the timing frequency synchronization and the carrier frequency synchronization by using the frequency bias estimation and the carrier frequency bias estimation. The invention also relates to a corresponding receiving end of the united synchronized method. The technical solution of the invention provides the united synchronized method and the receiving end thereof, which can offer reliable and precise synchronization under the bad transmitting condition; the invention is suitable for the transmitting system having the part circulated characteristic for all the transmitting serials.
Owner:TSINGHUA UNIV
Inhomogeneous sensor array broadband signal direction-of-arrival estimation method
ActiveCN109407045AAchieve estimatesReduce complexityDirection/deviation determination systemsSensor arrayFast Fourier transform
The present invention discloses an inhomogeneous sensor array broadband signal direction-of-arrival (DOA) estimation method. The method comprises the following steps of: S1, performing sliding windowfast Fourier transform of a sample sequence in an inhomogeneous sensor array, and constructing an actual value weighting sample covariance vector yl; S2, constructing a corresponding over-complete array flow-pattern matrix [Phi]l; S3, employing the actual value weighting sample covariance vector yl and the over-complete array flow-pattern matrix [Phi]l to set an initial value [gamma]init of a space joint sparse representation vector [gamma] and an initial value [lambda]init of a regularization parameter [lambda]; S4, employing the actual value weighting sample covariance vector yl and the over-complete array flow-pattern matrix [Phi]l to update the space joint sparse representation vector [gamma] and the regularization parameter [lambda]; S5, when the [gamma] obtained through the ith iteration and the [gamma]<i+1> obtained through the (i+1)the iteration meet ||[gamma]-[gamma]<i+1>||2 / ||[gamma]||2<[alpha] or achieve the maximum iteration times Pmax, stopping the iteration, or else, returning the step S4; and S6, searching all the peak values of the space joint sparse representation vector [gamma], and outputting DO estimation values of the broadband signals.
Owner:SUZHOU UNIV
Contour error real-time estimation method based on spatial arc approximation
The invention belongs to the technical field of precision high-efficiency numerical control machining, and relates to a contour error real-time estimation method based on spatial arc approximation in a spline curve interpolation process. According to the method, a parameter initial value for Newton iteration on a parameter curve is calculated based on a first-order Taylor series expansion method before a perpendicular foot is calculated in each Newton iteration, and then a single iteration parameter final value is calculated according to the parameter initial value by using a Newton iteration method. In order to avoid greatly increasing the calculation time of the algorithm, circulation is ended under double constraints of an iteration terminating precision condition and a maximum iteration number condition to obtain a parameter estimation value of the perpendicular foot, and a contour error vector estimation value is calculated. The method still can effectively guarantee the estimation precision of a contour error when the follow-up error is relatively large, and has great significance for improving the spline curve interpolation machining contour precision of a high-grade numerically-controlled machine tool.
Owner:DALIAN UNIV OF TECH
Contrast optimization self-focusing method based on hypersonic platform synthetic aperture radar (SAR)
ActiveCN102540188AImprove estimation accuracyAdaptableRadio wave reradiation/reflectionHigh signal intensitySynthetic aperture radar
Owner:XIDIAN UNIV
Method for estimating roll angle and pitch angle of vehicle based on recursive least square
The invention discloses a method for estimating a roll angle and a pitch angle of a vehicle based on a recursive least square. Through the method, a vehicle dynamic model conforming to driving characteristics of a four-wheel vehicle running on the land is established; furthermore, the real-time and accurate estimation of the roll angle and the pitch angle of the vehicle can be realized by a recursive least square method with a forgetting factor. According to the method, only a low-cost vehicle-mounted sensor is needed, so that the cost is low; the estimated information of the roll angle and the pitch angle can meet requirements on integrated navigation and location of the vehicle.
Owner:SOUTHEAST UNIV
Single-image human face posture estimation method based on depth value
ActiveCN106570460AOvercoming the defects of pathological process of pose estimationGuaranteed estimation accuracyCharacter and pattern recognitionActive shape modelEstimation methods
The invention relates to a single-image human face posture estimation method based on a depth value, and the method comprises the following steps: obtaining a human face with a to-be-estimated posture; converting the human face with a to-be-estimated posture into a gray scale image, and carrying out the noise reduction and standardization processing; introducing an affine transformation invariance initialization principle to build an initial model, improving a conventional active shape model method, and extracting the two-dimensional values of ten human face feature points; solving the depth values of ten human face feature points through the perspective imaging principle through employing an iteration algorithm; estimating a human face posture estimation target function; carrying out the primary estimation of the human face posture through four human face feature points, enabling the primary estimation value to serve as the input value for the least square optimization calculation of a target function, and outputting a human face posture result of secondary estimation; carrying out the further optimization of a least square optimization calculation result through employing an M-estimation algorithm, and outputting a final estimation result. The invention overcomes a pathological problem of posture estimation, and is good in posture estimation precision and robustness.
Owner:SANMING UNIV
Millimeter-wave system channel estimation method low in complexity
ActiveCN107566305AImprove estimation efficiencyReduce complexityBaseband system detailsEstimation methodsMillimetre wave
The invention discloses a millimeter-wave system channel estimation method low in complexity. The method includes the following steps: firstly, a receiving end uses a first-order codebook to estimatea pair of azimuths AOA and AOD, and then establishes a set on the basis of the defined quantization precision estimated the second time and the number of quantization angles estimated the second time;secondly, the receiving end uses the set obtained in the first step and also a second-order codebook to conduct azimuth estimation at the second-order precision; and thirdly, the receiving end utilizes a least square method to estimate fading of channels corresponding to the azimuths, and determines whether channel estimation is carried out according to a result. Through utilization of sparsity of a millimeter-wave system channel and redundancy of a sparse dictionary in a compression sensing technology, a channel estimation process is quantified through angles to be decomposed into two-complexity channel estimation processes. According to the method, the number of searching of the sparse dictionary is reduced, the millimeter-wave system channel estimation efficiency is increased, and thechannel estimation complexity of channel estimation is reduced effectively while the estimation precision is guaranteed.
Owner:NANJING UNIV OF POSTS & TELECOMM
A substation battery multifunction control system and a control method thereof
InactiveCN109004696AAccurate Status DataImprove estimation accuracyCharge equalisation circuitElectric powerElectricityControl system
The invention relates to a multifunctional control system and a control method of a battery used in a substation, which is characterized in that the multifunctional control system comprises a currentacquisition module, an input end of the current acquisition module is connected with a current sensor, and an output end is connected with an input end of an A / D converter. The input end of the temperature acquisition module is connected with the temperature sensor, and the output end is connected with the input end of the A / D converter. The output of A / D converter is connected with CPU through I / O interface. The CPU is also connected with human-computer interaction module, discharge load and voltage balancing module through I / O interface, and the discharge load and voltage balancing module are electrically connected with each single battery respectively. The control method comprises the following steps of: balancing control of a battery pack; SOC estimation of battery pack; measurement ofinternal resistance of battery pack.
Owner:STATE GRID CORP OF CHINA +2
Quick global motion estimation method based on motion vector cancellation and differential principle
InactiveCN101453557AGuaranteed estimation accuracyHigh real-time requirementsTelevision system detailsColor television detailsMotion vectorVideo processing
The invention discloses a method for estimating quick global motion based on motion vector cancellation and a difference principle. The method comprises: firstly, inputting the current frame and a reference frame of a video image, and acquiring a motion vector of each pixel point of the video image by an optic flow method to form a motion vector field; secondly, constructing a global motion model of the video image on the motion vector field; thirdly, estimating a translation parameter T of global motion by utilization of the characteristic that motion vectors in diagonal and symmetrical positions on the motion vector field can cancel other motion components except a translation motion component; fourthly, estimating a conversion parameter A of the global motion by utilization of the difference principle of motion vector pairs on the same row and motion vector pairs on the same column on the motion vector field; and fifthly, substituting the translation parameter T and the conversion parameter A into the global motion model, and completing global motion estimation of the video image. The method greatly shortens the computation time under the condition of guaranteeing the estimation precision, and can be applied to a video processing system with higher real-time requirement.
Owner:ZHEJIANG UNIV
Time-to-go online estimation method
ActiveCN107943079ANo dependencyGood precisionPosition/course control in three dimensionsGuidance systemEstimation methods
Provided is a time-to-go online estimation method, which is characterized by establishing models through measured missile-target relative distance and a system identification method and a regression analysis method; estimating miss distance through the established models and the currently known missile-target relative distance to obtain a miss distance estimated value, time corresponding to the miss distance estimated value being intercept time of a predicting missile for a target; calculating a time interval value between missile-target relative distance estimation time and the intercept timeof the predicting missile for the target, and multiplying the time interval value with a sampling period to obtain a time-to-go estimation component of the current time; and obtaining a time-to-go fusion estimation value through a Fisher information fusion method. The time-to-go online estimation method only needs the missile-target relative distance and the sampling period, wherein the missile-target relative distance is obtained through measurement and the sampling period is given by a guiding system, so that the method has better calculation efficiency and feasibility; and besides, the method has higher robustness.
Owner:XI AN JIAOTONG UNIV
Consistency clock synchronization relative frequency offset estimation method based on weighted median
ActiveCN111416785ARelative frequency deviation is accurateSufficient storage capacitySynchronisation arrangementMulti-frequency code systemsLine sensorFrequency offset
The invention relates to a consistency clock synchronization relative frequency offset estimation method based on a weighted median, and belongs to the technical field of wireless sensor networks. Themethod is oriented to a wireless sensor network scene in which communication time delay is exponentially and randomly distributed; a relative clock relation between nodes is considered, a Laplace variable model is obtained through timestamp data processing, then a weighted median method is adopted to estimate relative frequency offset, logic clock parameters of the nodes are compensated in combination with an average consistency method, and finally the effect that logic clocks of the nodes in a network are kept synchronous is achieved. The invention provides two relative frequency offset estimation methods, namely an interval-based weighted median estimation method and a threshold-based weighted median estimation method. The time stamp interval is estimated by searching an optimization value of the time stamp interval, and the method is suitable for scenes with high requirements on relative frequency offset estimation precision; the latter reduces the storage requirement of the estimation method by setting a threshold value, and is suitable for a node storage resource limited scene.
Owner:CHONGQING UNIV OF POSTS & TELECOMM
Method for estimating attitude angles of rescuing and obstacle-clearing vehicle
ActiveCN103616013ALow costHigh precisionAngle measurementIncline measurementEarly warning systemEngineering
The invention discloses a method for estimating the attitude angles of a rescuing and obstacle-clearing vehicle. According to the method, the rescuing and obstacle-clearing vehicle is subjected to dynamics modeling according to the work characteristics of the rescuing and obstacle-clearing vehicle; the estimated values of the attitude angles, such as side rake angle, pitch angle and the like, of the rescuing and obstacle-clearing vehicle are obtained by a recursive least-square method, and can be applied to attitude monitoring and dangerous attitude early warning of the rescuing and obstacle-clearing vehicle, so the method has the significant advantages of high precision, low cost, high real-time property and the like.
Owner:SOUTHEAST UNIV
Method for tracking targets of wireless sensor network on basis of information consistency weight optimization
InactiveCN103313386AGuaranteed estimation accuracyImprove reliabilityNetwork topologiesPrior informationObservation matrix
The invention discloses a method for tracking targets of a wireless sensor network on the basis of information consistency weight optimization. The method includes (1), initializing prior information vectors and prior information matrixes of various nodes; (2), computing observation vectors of the various nodes; (3), computing local observation vectors and local observation matrixes of the various nodes; (4), broadcasting information of the various nodes to neighbor nodes; (5), computing fused local observation vectors and fused local observation matrixes of the various nodes; (6), optimizing consistency weights; (7), computing consistency-fused local information vectors and consistency-fused local information matrixes of the various nodes; (8), acquiring information vector consistency estimation and information matrix consistency estimation of the various nodes; (9), acquiring target state predicted values and target state estimated values of the various nodes; (10), predicting and updating the prior information vectors and the prior information matrixes of the various nodes. The method has the advantage that the state estimation accuracy and the state estimation consistency of the various nodes in the sensor network are improved.
Owner:ZHEJIANG UNIV
IMU full parameter error fast calibration method based on backtracking theory
ActiveCN110361031AHigh speedReduce complexityMeasurement devicesAccelerometerPropagation of uncertainty
The invention discloses an IMU full parameter error fast calibration method based on the backtracking theory. A calibration trajectory of forward and reverse rotation under three positions is designed. The observability of the error state is analyzed through the error propagation law of the inertial component, and the IMU full parameter error can be rapidly calibrated in a short period of time bythe calibration method based on the backtracking frame theory. The method has the beneficial effects that the calibration method based on the system level can calibrate the zero position error, the scale factor error and the installation error of the fiber optic gyro and the accelerometer and the rod arm error of the accelerometer in the dynamic environment. The arrangement of the calibration trajectory can be simplified, the calibration time can be greatly shortened and the efficiency of IMU error calibration can be improved.
Owner:SOUTHEAST UNIV
Data-driven adaptive anti-interference controller structure and estimation method thereof
ActiveCN110687800ARealize online estimationEasy to controlAdaptive controlInterference resistanceState observer
The invention discloses a data-driven adaptive anti-interference controller structure and a working method thereof. The controller structure comprises an input controller, an extended state observer,a control gain estimation module and a second-order nonlinear system; and the second-order nonlinear system is a second-order nonlinear system with unknown control gain. The input controller only needs the parameters output by the control gain estimation module and does not need a control gain parameter b; when the control gain of the second-order nonlinear system is unknown, the uncertainty and the control gain of the second-order nonlinear system are estimated online at the same time. By establishing the control gain estimation module, the online estimation of the control gain of the second-order nonlinear system within finite time is realized. By introducing the state tracking error signal xe, the effective tracking of the expected state is achieved, the control state is converged to the expected state, the parameter estimation accuracy is effectively guaranteed, and the accurate control over the second-order nonlinear system is achieved.
Owner:DALIAN MARITIME UNIVERSITY
Quad-rotor roll angle and pitch angle fault tolerance estimation method based on torque model assistance
ActiveCN108981709AAccurate estimateGuaranteed estimation accuracyNavigational calculation instrumentsNavigation by speed/acceleration measurementsFault toleranceDynamic models
The invention discloses a quad-rotor roll angle and pitch angle fault tolerance estimation method based on the torque model assistance. The steps are: periodically reading quadrotor aircraft on-boardsensor information at the time k, performing a fault detection filter and the fault location strategy, and judging x axis gyro, y axis gyro, roll moment model, pitch moment model fault; determining the state equation of each sub-filter according to the fault location result, and performing data fusion of each sub-filter; performing global filter according to the fault detection result, separatingfault of each sub-filter, carrying out data fusion of the fault-free sub-filter, and obtaining x axis angular velocity, y axis angular velocity, roll angle, and pitch angle information; resetting andupdating according to the global filter result, and performing a system reset strategy. The method forms the redundancy of the x and y axis gyros through the dynamic model of the quadrotor, realizes the fault detection and system reset of the x and y axis gyros, and still obtains the accurate estimate of the attitude angle and the heading angle when the gyros are faulty.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
Power grid harmonic source positioning method based on wide-area monitoring
InactiveCN109581103AEasy to operateGuaranteed estimation accuracyElectrical testingWide areaState variable
The invention discloses a power grid harmonic source positioning algorithm based on wide-area monitoring. The positioning algorithm comprises the following steps: applying power distribution line measurement to harmonic state estimation and harmonic source positioning, taking the voltage current and like state variables collected by a wide-area monitoring system as the basis, proposing a specificoptimization algorithm according to the weighted least square method, and realizing the power grid harmonic source positioning by utilizing the phasor difference method. The harmonic source positioning based on the wide-area measurement system sufficiently plays the wide-area low-cost characteristics, the operation process is optimized, the estimation precision is guaranteed, the full-network harmonic voltage state is obtained, and the harmonic source detection sensitivity and the positioning accuracy are much better than the traditional detection. And the method disclosed by the invention hasimportant significance for the analysis processing of the power grid harmonic source.
Owner:SHANGHAI JIAO TONG UNIV
Non-cooperative signal sensing system and multi-dimensional parameter estimation method of satellite-borne passive SAR
PendingCN114002673AIncrease flexibilityLarge imaging duty cycleRadio wave reradiation/reflectionRadarImage detection
The invention discloses a non-cooperative signal sensing system and a multi-dimensional parameter estimation method of a satellite-borne passive SAR and belongs to the technical field of radars. The invention provides a non-cooperative SAR signal sensing system and the non-cooperative SAR signal multi-dimensional parameter estimation method. The non-cooperative SAR signal sensing system comprises a zenith sensing antenna, a direct signal array receiving unit, a ground detection antenna and an echo signal array receiving unit, and receives non-cooperative SAR direct signals and echo signals. The non-cooperative SAR signal multi-dimensional parameter estimation method involves a direct-arrival signal time-frequency-space characteristic estimation unit and an antenna beam pointing parameter estimation unit and achieves multi-dimensional parameter estimation and antenna pointing estimation of non-cooperative SAR signals. Compared with a traditional satellite-borne SAR system, the satellite-borne passive SAR does not need to transmit any signal, can sense and capture available non-cooperative SAR signal sources in space in real time, and uses the non-cooperative SAR signal sources to perform double-station SAR imaging detection.
Owner:SPACE STAR TECH CO LTD
Strapdown seeker nonsingular line-of-sight angular velocity extraction method based on inclined coordinate system
InactiveCN111238474AExtended strike angle envelopeAvoid divergenceNavigational calculation instrumentsNavigation by speed/acceleration measurementsAngular velocityEngineering
The invention discloses a strapdown seeker nonsingular line-of-sight angular velocity extraction method based on an inclined coordinate system, and belongs to the technical field of guidance and control. On the basis of a traditional coordinate system, the method comprises the steps of: designing an inclined ground coordinate system, an inclined sight coordinate system and an inclined projectile body coordinate system; deriving a direction cosine matrix between coordinate systems; establishing a missile-target relative motion equation under an inclined sight line coordinate system; deriving the missile-target relative motion equation twice to obtain a relation equation between a second derivative of the inclined sight line angular velocity and the missile-target relative acceleration; andestablishing a nonsingular filtering state equation. According to coordinate conversion from the inclined projectile system to the inclined ground system, the conversion equation of the lower body sight angle of the inclined projectile system is obtained by combining an inclined sight angle with projectile body attitude information, the observation equation is established, the divergence problem of a yaw angle and a roll angle caused by singularity is avoided, and meanwhile, the estimation precision of the inertial sight angular velocity during vertical strike is ensured.
Owner:HARBIN INST OF TECH
Lithium battery SOC estimation method for preventing from filter divergence
InactiveCN108872865AImprove estimation accuracyImprove stabilityElectrical testingEstimation methodsEngineering
The present invention discloses a lithium battery SOC estimation method for preventing from filter divergence, and relates to the technical field of electric car lithium battery state estimation. Themethod mainly comprises the steps of: I, obtaining a lithium battery SOC starting value through an open-circuit voltage method; II, considering influences of system noise and observation noise, and employing an improved Sage-Husa adaptive extended Kalman filtering algorithm to estimate a real-time SOC value; and III, employing filter divergence criterion for the previous step to perform filter divergence determination, when the filter divergence determination does not meet a criterion condition, constructing an index freezing factor at a Kalman gain matrix to avoid filter divergence. On the basis of the extended Kalman filtering algorithm, a noise estimation value device is added to ensure the estimation precision of the SOC, avoid the generation of filter divergence in a severe work condition and improve the stability of the system estimation.
Owner:TAIYUAN UNIV OF TECH
OFDM system fast-change channel estimation method based on double weighing
ActiveCN103905347AGuaranteed estimation accuracyEffective trackingBaseband system detailsMulti-frequency code systemsEstimation methodsCarrier signal
The invention provides an OFDM system fast-change channel estimation method based on double weighing. The method includes the following steps that pilot signals are extracted from receiving data of a system, and the channel response at a pilot frequency position is estimated; for each pilot frequency sub-carrier, a predicated value of the channel response at the data position of the corresponding pilot frequency sub-carrier is obtained through forward prediction; the predicted values of the channel responses are used for conducting balance and judgment on the received data, feedback information is obtained, the predicted values of the channel responses are corrected, and the channel responses of the whole pilot frequency sub-carriers are obtained; the channel response of each pilot frequency sub-carrier is used for conducting balance and judgment on the receive data, and error parameters of the channel response of each pilot frequency sub-carrier are obtained; interpolation coefficients of each pilot frequency sub-carrier are calculated according to the error parameters, interpolation in the frequency direction is performed, and the channel response of the system is obtained. According to the OFDM system fast-change channel estimation method based on double weighing, effective tracking of a fast time-varying channel can be achieved, and the accuracy of channel estimation is improved.
Owner:BEIJING UNIV OF POSTS & TELECOMM
Wireless sensor network target tracking method based on informational consistency
InactiveCN103313384AGuaranteed estimation accuracyImprove reliabilityNetwork topologiesPredictive valueAlgorithm
The invention discloses a wireless sensor network target tracking method based on informational consistency. The method includes: (1) initiating a prior information vector and a prior information matrix of each node; (2) calculating an observation vector of each node; (3) calculating a local observation vector and a local observation matrix of each node; (4) enabling each node to broadcast information to adjacent nodes; (5) calculating a fused local observation vector and a fused local observation matrix of each node; (6) calculating a consistency fusion local information vector and consistency fusion local information matrix of each node; (7) acquiring an information vector consistency estimation and an information matrix consistency estimation of each node; (8) acquiring a predictive value and an estimation value of a target state of each node; and (9) predicting and updating the prior information vector and the prior information matrix of each node. Information filtering and consistency strategies are combined, and accordingly accuracy and consistency of state estimation of each node in a sensor network are improved.
Owner:ZHEJIANG UNIV
Angle of arrival estimation method and apparatus
ActiveCN110857973AGuaranteed estimation accuracyRadio wave finder detailsSpatial transmit diversityReference antennaPhase difference
The invention discloses an angle of arrival estimation method and apparatus. According to the method, a first device acquires first signals from a second device through a reference antenna and a firstantenna group and determines a first CSI and acquires second signals from the second device through the reference antenna and a second antenna group and determines a second CSI; the first device determines a phase difference vector between the first signals and the second signals according to a vector corresponding to the reference antenna in the first CSI and a vector corresponding to the reference antenna in the second CSI, and compensates the second CSI by using the phase difference vector; and the angle of arrival of the second device is estimated according to the first CSI and the compensated second CSI. When the angle of arrival of the second device is estimated, the signals received by the reference antenna, the first antenna group and the second antenna are utilized, and therefore, the estimation precision of the angle of arrival is improved, and the number of radio frequency circuits does not need to be increased.
Owner:HUAWEI TECH CO LTD
Quad-rotor torque model/directional gyro/magnetic sensor fault-tolerant integrated navigation method
ActiveCN108981708AAchieve isolationAccurate estimateNavigational calculation instrumentsNavigation by speed/acceleration measurementsAccurate estimationEquation of state
The invention discloses a quad-rotor torque model / directional gyro / magnetic sensor fault-tolerant integrated navigation method. The method comprises the following steps: periodically reading information of a quad-rotor aircraft airborne sensor at a moment k; executing a fault detecting filter and a fault location strategy, and judging faults of a z-axis gyro, a torque model and a magnetic sensor;determining a state equation of each sub-filter, and performing data fusion; according to a fault detecting result, performing fault isolation; executing a global filter, and performing the data fusion on the sub-filter without the fault, to obtain course angle information; resetting state quantities of each sub-filter and the fault detecting filter, and executing a system reset strategy. The method is capable of, through the torque model of a quad-rotor aircraft, forming redundancy of the z-axis gyro, realizing fault detection of the z-axis gyro, the magnetic sensor and the torque model and the system reset, and acquiring accurate estimation of an attitude angle and a course angle still while the gyro is failure.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
Rotor position and rotating speed detection method based on counter potential open-loop estimation
InactiveCN110995093AImprove qualityGuaranteed reliabilityElectronic commutation motor controlVector control systemsDifferentiatorLow-pass filter
The invention discloses a rotor position and rotating speed detection method based on counter potential open-loop estimation, and belongs to the technical field of closed cycle power generation. The method comprises the following implementation steps: firstly, a linear tracking differentiator is introduced to preprocess winding current to suppress noise, then a variable parameter low-pass filter is adopted to filter back potential of a motor, delay of PWM sampling is compensated at a high rotating speed, and finally, a dead zone compensation unit is introduced to compensate voltage waveform distortion caused by an inverter dead zone. Stable power generation of the power generator in the closed circulation system can be achieved, the motor body does not need to be provided with a position sensor, and the reliability of the system is improved.
Owner:BEIJING POWER MACHINERY INST
Joint Estimation Method for State of Charge, State of Health and State of Power of Lithium-ion Batteries
ActiveCN105301509BGuaranteed estimation accuracyImprove state estimation performanceElectrical testingInternal resistanceState of health
Owner:TSINGHUA UNIV
Direction of arrival estimation method based on grid partial refinement
ActiveCN109783960AGuaranteed estimation accuracyGrid Points ReductionCharacter and pattern recognitionSpecial data processing applicationsEstimation methodsDirection of arrival
The invention discloses a direction of arrival estimation method based on grid partial refinement. Through learning and fission processes, in the fission process, new grid points are generated to refine the grid. The learning process is continuously close to the direction of arrival, grids near the real direction of arrival are finely divided, and grid areas far away from the direction of arrivalare coarsely divided, so that partial refinement of the grids is realized, the estimation precision is ensured, and compared with a previous off-grid DOA estimation algorithm, the number of grid points is greatly reduced, and the calculation amount is reduced accordingly. According to the method, the information source number does not need to serve as a priori, grid division is as sparse as possible, the grid number is reduced, therefore, the calculation complexity is reduced, and the algorithm consumes less time. And under the condition of very sparse initial lattice point division, the estimation precision of the algorithm is ensured through minimum interval threshold self-definition.
Owner:GUILIN UNIV OF ELECTRONIC TECH
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