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205results about How to "Improve estimation accuracy" patented technology

Linear frequency-modulated parameter estimating method and implementing device thereof

The invention belongs to the technical field of digital signal processing and provides a linear frequency-modulated parameter estimating method with high precision, low complexity, high speed and high efficiency and an implementing device thereof. The invention adopts a technical scheme that: by means of an energy barycentre interpolation estimation and Radon ambiguity transformation (RAT) based modulating frequency estimating method, the method mainly comprises the following steps of: for a given input signal s(n), calculating an ambiguity function AFs(tau, xi) of the input signal s(n); exchanging scanning straight lines xi=k tau continuously; figuring out the projection of AFs(tau, xi) on the scanning straight lines by means of Radon transformation; recording all projection values; constructing a panorama discrete spectrum; searching out the peak position of the panorama discrete spectrum; estimating the projection value of the actual peak value; obtaining the estimated value of thesignal modulating frequency; searching out the peak value spectrum of a fractional order Fourier spectrum; and figuring out the energy barycentre position of the spectrum so as to estimate the signalbarycentre frequency. The method is mainly applied to the linear modulating frequency signal parameter estimation in the digital signal processing.
Owner:LIANYUNGANG RES INST NANJING UNIV OF SCI & TECH

Multiple-target and send-receive angle estimation method of double-base multiple-input and multiple-output radar

InactiveCN102981152AImprove estimation accuracyGood angle estimation performanceWave based measurement systemsMatched filterEcho signal
The invention provides a multiple-target and send-receive angle estimation method of a double-base multiple-input and multiple-output radar. A receiving end collects echo signals of every receiving antenna through an analog to digital (A/D) sampling module. The collected signals passes through a matched filter group, signals corresponding to every launching channel are separated, and receiving data of a virtual array is obtained, wherein the number of array elements is MN. The receiving data is expanded and is transformed into a real number field by utilizing Unitary transformation. A covariance matrix is calculated and is disassembled by utilizing characteristic value to obtain an actual value signal subspace and an actual value signal subspace. In the end, a target DOD is obtained by utilizing Unitary ESPRIT, and a target DOA is obtained by utilizing Unitary Root-MUSIC. According to the multiple-target and send-receive angle estimation method of the double-base multiple-input and multiple-output radar, the send-receive angle is automatically paired, extra pairing operation is not needed, and cross bearing of the target is achieved by utilizing the send-receive angle of the target. The multiple-target and send-receive angle estimation method of the double-base multiple-input and multiple-output radar has the advantages of being high in estimated accuracy and low in computing complexity.
Owner:HARBIN ENG UNIV

Estimation method for endurance mileage of electric vehicle

The invention discloses an estimation method for endurance mileage of an electric vehicle, which comprises the following steps: 1, collecting battery electric quantity, consumed in the corresponding path, of the electric vehicle, and counting in advance to acquire data of the battery electric quantity averagely consumed by each path; 2, acquiring a running path from the current position to the destination position through a navigation system, and acquiring data of the battery electric quantity needing to be consumed according to the data of the battery electric quantity averagely consumed by each path; 3, comparing the data of the current battery electric quantity of the electric vehicle with the data of the battery electric quantity needing to be consumed; and 4, under the condition that the data of the current battery electric quantity of the electric vehicle is greater than the data of the battery electric quantity needing to be consumed, enabling the electric vehicle to prompt the data of the surplus electric quantity after arrival; under the condition that the data of the current battery electric quantity of the electric vehicle is less than the data of the battery electric quantity needing to be consumed, enabling the electric vehicle to prompt the position information that the electric vehicle can arrive in the running path; and under the condition that the data of the current battery electric quantity of the electric vehicle is equal to the data of the battery electric quantity needing to be consumed, enabling the electric vehicle to prompt that the surplus electric quantity is 0 after arrival. The estimation method overcomes the problem of very poor accuracy of an endurance mileage estimation result in the prior art and realizes accurate prediction of the endurance mileage.
Owner:ANHUI NORMAL UNIV

Method for estimating a tire running condition and an apparatus for effecting the method and a tire with sensors disposed therein

InactiveUS20070295074A1Running condition can be accuratelyImprove estimation accuracyTyre measurementsRoads maintainenceAutomotive engineeringContact condition
A method for estimating accurately and stably the change of forces exerted on the tire or change of contact condition with the ground of the tire and an apparatus for putting it in operation.
Prepare a tire with sensors disposed therein such that the first and the second deformation amount measurement means 11A and 11B positioned on the vehicle body side and on outside, respectively, each of which comprises a lengthy detection portion 11a made of a conductive rubber member buried in the tire tread 21 and placed in a circumferential direction of the tire and comprises of detection electrodes 11b, 11b at both ends of the detection portion; and upon computing contact length with the ground of the tire vehicle body side and on the outside, from detected resistance value of the detection portion 11a included in the means of 11A and the wheel speed and from the resistance value of 11a included in the means of 11A and the wheel speed and from the resistance value of 11a included in the means 11B and the wheel speed, respectively, the load exerted on the tire and the lateral force exerted on the tire can be estimated form the average value and the difference value, respectively of the contact length on the vehicle body side and on the outside, respectively.
Owner:BRIDGESTONE CORP

Carrier frequency deviation estimation method and device

The invention discloses a method for estimating a carrier frequency offset and a device thereof. The invention is used for solving the problem of low estimation precision of the carrier frequency offset in an orthogonal frequency division multiplexing system existing in the prior art. The method in the invention sets a first threshold of the frequency offset estimation range in advance. The method comprises the following steps: A. a pilot symbol of the orthogonal frequency division multiplexing system is used for obtaining an estimation value of a first relative frequency offset; B. an absolute value of the first relative frequency offset estimation value is less than the first threshold value, a second relative frequency offset estimation value is obtained through cyclic prefixes of the orthogonal frequency division multiplexing system symbol and the orthogonal frequency division multiplexing system symbol; C. the carrier frequency offset estimation value of the orthogonal frequency division multiplexing system is obtained through carrying out a weighted average to the first relative frequency offset estimation value and the second relative frequency offset estimation value. The invention is used for estimating the carrier frequency offset of the orthogonal frequency division multiplexing system and increases the estimation precision.
Owner:DATANG MOBILE COMM EQUIP CO LTD

Method and system for inverting ground PM 2.5 through combination of geostatistical interpolation and satellite remote sensing

InactiveCN106404620AImprove estimation accuracyMake up for the inestimableParticle suspension analysisSatellite remote sensingVariogram
The invention provides a method and system for inverting the ground PM 2.5 through combination of geostatistical interpolation and satellite remote sensing. The method comprises: based on a space-time kriging interpolation model and a constructed space-time variogram model, obtaining a first concentration value of the ground PM 2.5 of a to-be-inverted region; based on a constructed satellite AOD inversion model, obtaining a second concentration value of the ground PM 2.5 of the to-be-inverted region; and fusing the first and second concentration values to estimate a final concentration value of the ground PM 2.5 of the to-be-inverted region. A weight relationship is established according to the root-mean-square error of the first and second concentration values, and the first and second concentration values are fused according to the weight relationship to estimate the final concentration value of the ground PM 2.5 of the to-be-inverted region. According to the method and system, the estimation accuracy of PM 2.5 is improved in a situation that ground monitoring stations are less, and the defect that PM 2.5 cannot be estimated at the place where AOD data is lost is overcome.
Owner:INST OF REMOTE SENSING & DIGITAL EARTH CHINESE ACADEMY OF SCI

Side slip angle estimation method and system based on robust unscented kalman filtering

The invention discloses a side slip angle estimation method and system based on robust unscented kalman filtering. The method includes the steps that a three-freedom-degree vehicle dynamics model related to a side slip angle is established, a state equation and an observation equation of an unscented kalman filter are determined according to the model, and the input quantity, the state quantity and the observation quantity are determined, wherein the input quantity comprises the front wheel rotation angle and the longitudinal accelerated speed, the state quantity comprises the side slip angle,the yaw velocity and the longitudinal vehicle speed, and the observation quantity comprises the lateral accelerated speed and the yaw velocity; the weight factor is calculated through an M estimatoralgorithm; and in combination with the weight factor, the state quantity at the current moment, the state equation and the observation equation, the side slip angle at the next moment is estimated through an unscented kalman filtering algorithm. The M estimator algorithm and the unscented kalman filtering algorithm are combined to restrain the influence caused by outliers, the robustness of the unscented kalman filtering algorithm to the outliers in observation signals is improved, and the estimation accuracy of the vehicle side slip angle is improved.
Owner:BEIJING INSTITUTE OF TECHNOLOGYGY

Imaging method and device based on orthogonal multiple frequency ultrasonic stable-state echo signal

The invention discloses an imaging method and a device on the basis of orthogonal multi-frequency ultrasonic steady echo signal. The method uses an orthogonal frequency division multiplexing modulation type to form multi-frequency continuous baseband signals which are orthogonal with each other; the multi-frequency continuous baseband signals are modulated as multi-frequency ultrasonic continuous emission signals and sent out by an ultrasonic probe; the ultrasonic probe detects the steady echo signals which are reflected back; the steady echo signals are equivalent to the superposing signals; the received multi-frequency continuous baseband signals after modulation are orthogonally decomposed, each path of receiving signals are decomposed by the characteristic that each path of signals are orthogonal with each other, the amplitude of each interface reflection echo and the position thereof corresponding to the incident interface are calculated so as to carry out the image forming. The device of the invention comprises an ultrasonic probe, a control unit, and an operation unit, a receiving/emitting unit, a processing unit and a display unit which are respectively connected with the control unit; the ultrasonic probe is connected with the receiving/emitting unit; the processing unit is respectively connected with the receiving/emitting unit and the display unit; the method and the device of the invention has precise image forming and good anti-interference performance, and reduces the cost by adopting a single probe.
Owner:SOUTH CHINA UNIV OF TECH

Data-guiding channel estimation method for OFDM systems, and implementation device thereof

The invention provides a data-guiding channel estimation method for OFDM systems, and an implementation device thereof, which belong to the technical field of digital information transmission. The method demodulates and recovers frequency-domain data symbols at the receiving end of an OFDM system and performs channel estimation. The method comprises the steps of utilizing a frame structure to obtain initial channel estimation result, building a time-domain signal frame and the cyclic convolution of channel impulse response, demodulating frequency-domain data symbols of a current frame, and performing data-guiding channel estimation and post processing. The device comprises an initial channel estimation module, a channel estimation gating module, a cyclic convolution building block, a frequency-domain data block demodulation module, a data-guiding channel estimation module, a channel estimation post-processing module and a control module. The method and the device use hidden informationcarried by frequency-domain data sent by the OFDM system in symbol modulation, as well as initial channel estimation provided by training information, completes receiving the channel estimation of all signal frames, and can reduce complexity, improve precision and increase the utilization ratio of frequency spectrum, mobile performance and other effects.
Owner:TSINGHUA UNIV

Ultrasonic-assisted microphone array speech enhancement device

InactiveCN102800325AImprove estimation accuracyAchieve real-time acquisitionSpeech analysisTransit timeVIT signals
The invention discloses an ultrasonic-assisted microphone array speech enhancement device, and relates to voice signal treatment. The ultrasonic-assisted microphone array speech enhancement device comprises an equidistant linear array, a preamplification circuit, an analog-digital conversion circuit, two ultrasonic sensors, a transmitting circuit, a receiving circuit, a position computation module and a weighted stacking module, wherein, the equidistant linear array comprises five microphones; an output end of the linear array is sequentially connected with the preamplification circuit, the analog-digital conversion circuit, data cables and the weighted stacking module; the sensors are installed on extended lines at two ends of the linear array; the transmitting circuit and the receiving circuit utilize the sensors to transmit signals, and the received signals are processed through preamplification and analog-digital conversion and then are sent to the position computation module; in addition, the position computation module acquires return wave receiving signals of the sensors for matched filtering so as to acquire the ultrasonic transit time from a target to the sensors, acquires sound source position information that is input to the weighted stacking module, calculates time-delay compensation values of channels, performs time-delay compensation and stacking on each channel receiving signal of a microphone array so as to enhance voice signals in sound source directions.
Owner:XIAMEN UNIV

Dpf accumulation amount estimating apparatus

A DPF accumulation amount estimating apparatus uses an integrated PM accumulation amount estimation logic which combines the difference between an engine PM emission amount and a PM regeneration amount and a DPF differential pressure model, thereby achieving minimized influences of changes in an exhaust gas flow rate and the like with resultant improved estimation accuracy. The DPF accumulation amount estimating apparatus for estimating the accumulation amount in a DPF (diesel particulate filter) provided therewith for removing PM (particulates (particulate matters)) in an exhaust gas, and includes a PM emission amount model in which a PM emission amount is set on the basis of the operating condition of an engine, a PM regeneration amount model in which a PM regeneration amount is set on the basis of the temperature difference between an outlet temperature and an inlet temperature of the DPF, and a DPF differential pressure model in which a PM accumulation amount is set on the basis of the differential pressure between an exhaust gas flow rate and the DPF, wherein the estimated PM accumulation amount of the DPF is calculated by adding a corrected PM accumulation amount obtained by correcting the estimated value of the DPF differential pressure model by using a coefficient K, which is determined on the basis of an engine speed and the fuel injection amount of an engine, to a difference between a PM emission amount and a PM regeneration amount.
Owner:MITSUBISHI HEAVY IND LTD

Fast time-varying channel estimation method based on simplified basis expansion model

The invention discloses a fast time-varying channel estimation method based on a simplified basis expansion model and mainly solves the problems of low estimated accuracy and high computation complexity of the existing technology. The method comprises the following implementation steps of 1) computing a matrix of a pilot symbol in a transform domain through a local pilot symbol; 2) obtaining a basis function matrix and a frequency domain matrix of a basis function based on a complex exponential basis expansion model; 3) carrying out fast Fourier transform on a receiving signal to obtain a frequency domain receiving signal and extracting a block-type pilot symbol from the receiving signal; 4) utilizing the received pilot symbol, the matrix of the transform domain in 1) and the frequency domain matrix in 2) to estimate a basis coefficient; 5) utilizing the basis coefficient to fit a time domain channel response matrix; and 6) utilizing a simplified time domain-frequency domain transformation formula to transform the time domain channel response matrix into a frequency domain channel response matrix. The method has the advantages of high estimated accuracy and low computation complexity and is suitable for an SC-FDMA system of the fixed block-type pilot.
Owner:XIDIAN UNIV

Battery capacity evaluation method

The invention relates to a battery capacity evaluation method. When a system is powered on, a power-on capacity estimating module estimates the power-on initial capacity of a batter according to a detected single battery open circuit voltage value and by inquiring the capacity ratio, corresponding to the open circuit voltage, in an open circuit voltage meter; capacity of the battery is calculated through the current integration method when the battery is charged or discharged in the last stage of a non-discharging period, and meanwhile the module automatically conducts capacity correction on the temperature characteristic of the battery capacity according to a temperature departure linear correction table, knows the ratio of the capacity at the current temperature to the full capacity by inquiring the temperature departure linear correction table, and calculates the modified value of the current capacity; in the last stage of a discharging period, the battery capacity estimating module estimates the capacity of the battery in the last stage of the discharging period by inquiring a residual capacity table; in the last stage of the charging period, the full capacity is renewed according to the current value at present and the capacity value at present. According to the battery capacity evaluation method, the charging and discharging characteristics of the battery are taken into full consideration at different temperatures and different magnitudes of multiplying power, the capacity of the battery is estimated through the current integration method and the data table inquiring method, and calculation accuracy is improved.
Owner:SHENYANG JUNWEI NEW ENERGY TECH CO LTD
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