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Optimization and Performance Enhancement of Gesture Recognition Algorithm Based on FMCW Millimeter-Wave Radar
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作者 Zhe He Jinlong Zhou +1 位作者 Decheng Bao Renjing Gao 《Journal of Beijing Institute of Technology》 EI CAS 2024年第5期412-421,共10页
Gesture recognition plays an increasingly important role as the requirements of intelligent systems for human-computer interaction methods increase.To improve the accuracy of the millimeter-wave radar gesture detectio... Gesture recognition plays an increasingly important role as the requirements of intelligent systems for human-computer interaction methods increase.To improve the accuracy of the millimeter-wave radar gesture detection algorithm with limited computational resources,this study improves the detection performance in terms of optimized features and interference filtering.The accuracy of the algorithm is improved by refining the combination of gesture features using a self-constructed dataset,and biometric filtering is introduced to reduce the interference of inanimate object motion.Finally,experiments demonstrate the effectiveness of the proposed algorithm in both mitigating interference from inanimate objects and accurately recognizing gestures.Results show a notable 93.29%average reduction in false detections achieved through the integration of biometric filtering into the algorithm’s interpretation of target movements.Additionally,the algorithm adeptly identifies the six gestures with an average accuracy of 96.84%on embedded systems. 展开更多
关键词 gesture recognition biometric filtering frequency-modulated continuous wave(FMCW)millimeter-wave radar feature optimization human-computer interaction
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Non-intrusive soil carbon content quantification methods using machine learning algorithms:A comparison of microwave and millimeter wave radar sensors
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作者 Di An YangQuan Chen 《Journal of Automation and Intelligence》 2023年第3期152-166,共15页
Agricultural and forestry biomass can be converted to biochar through pyrolysis gasification,making it a significant carbon source for soil.Applying biochar to soil is a carbon-negative process that helps combat clima... Agricultural and forestry biomass can be converted to biochar through pyrolysis gasification,making it a significant carbon source for soil.Applying biochar to soil is a carbon-negative process that helps combat climate change,sustain soil biodiversity,and regulate water cycling.However,quantifying soil carbon content conventionally is time-consuming,labor-intensive,imprecise,and expensive,making it difficult to accurately measure in-field soil carbon’s effect on storage water and nutrients.To address this challenge,this paper for the first time,reports on extensive lab tests demonstrating non-intrusive methods for sensing soil carbon and related smart biochar applications,such as differentiating between biochar types from various biomass feedstock species,monitoring soil moisture,and biochar water retention capacity using portable microwave and millimeter wave sensors,and machine learning.These methods can be scaled up by deploying the sensor in-field on a mobility platform,either ground or aerial.The paper provides details on the materials,methods,machine learning workflow,and results of our investigations.The significance of this work lays the foundation for assessing carbon-negative technology applications,such as soil carbon content accounting.We validated our quantification method using supervised machine learning algorithms by collecting real soil mixed with known biochar contents in the field.The results show that the millimeter wave sensor achieves high sensing accuracy(up to 100%)with proper classifiers selected and outperforms the microwave sensor by approximately 10%–15%accuracy in sensing soil carbon content. 展开更多
关键词 Soil carbon content sensing Carbon sequestration Microwave radar Millimeter wave radar Proximal sensing Machine learning
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A frequency domain estimation and compensation method for system synchronization parameters of distributed-HFSWR
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作者 WANG Hongyong SUO Ying +3 位作者 DENG Weibo WU Xiaochuan BAI Yang ZHANG Xin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1084-1097,共14页
To analyze the influence of time synchronization error,phase synchronization error,frequency synchronization error,internal delay of the transceiver system,and range error and angle error between the unit radars on th... To analyze the influence of time synchronization error,phase synchronization error,frequency synchronization error,internal delay of the transceiver system,and range error and angle error between the unit radars on the target detection performance,firstly,a spatial detection model of distributed high-frequency surface wave radar(distributed-HFSWR)is established in this paper.In this model,a method for accurate extraction of direct wave spectrum based on curve fitting is proposed to obtain accurate system internal delay and frequency synchronization error under complex electromagnetic environment background and low signal to noise ratio(SNR),and to compensate for the shift of range and Doppler frequency caused by time-frequency synchronization error.The direct wave component is extracted from the spectrum,the range estimation error and Doppler estimation error are reduced by the method of curve fitting,and the fitting accuracy of the parameters is improved.Then,the influence of frequency synchronization error on target range and radial Doppler velocity is quantitatively analyzed.The relationship between frequency synchronization error and radial Doppler velocity shift and range shift is given.Finally,the system synchronization parameters of the trial distributed-HFSWR are obtained by the proposed spectrum extraction method based on curve fitting,the experimental data is compensated to correct the shift of the target,and finally the correct target parameter information is obtained.Simulations and experimental results demonstrate the superiority and correctness of the proposed method,theoretical derivation and detection model proposed in this paper. 展开更多
关键词 distributed high-frequency surface wave radar(distributed-HFSWR) direct wave synchronization error curve fitting system synchronization parameter compensation
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An approach to estimate tidal dissipation with single-point high-frequency ground wave radar data
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作者 毛华斌 陈举 +1 位作者 邱春华 练树民 《Marine Science Bulletin》 2012年第2期46-55,共10页
Using the single-point ground wave (GW) radar data at Shensi Station and the water level data at three stations (Shengsi, Luchaogang and Daishan), the authors obtained the flow vectors from the radial velocity of ... Using the single-point ground wave (GW) radar data at Shensi Station and the water level data at three stations (Shengsi, Luchaogang and Daishan), the authors obtained the flow vectors from the radial velocity of GW radar observation, and calculate four sub-tidal harmonic constants (O1, K1, M2 and S2). The tidal characteristics derived from the GW radar dataset agreed well with those from the tidal gauge data. The authors also analyzed the tidal energy flux and tidal energy dissipation rate. There was a good relationship between the tidal energy dissipation rate and topography. The study showed a good way to calculate tidal energy dissipation rate using GW radar data. 展开更多
关键词 ground wave radar characteristic value tide type tidal energy flux tidaenergy dissipation
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Compensation for the Influence of Radar-Target Relative Speed on Step Frequency MMW Target Identification
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作者 杨军 祁载康 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期380-387,共8页
Aim To study the influence of radar-target relative speed on frequency MMW high-resolution ore-dimension distance profile and the compensation for it. Methods Based on the distance travelled by the electromagnetic wa... Aim To study the influence of radar-target relative speed on frequency MMW high-resolution ore-dimension distance profile and the compensation for it. Methods Based on the distance travelled by the electromagnetic wave, analyses were made for the compensation algorithm and the expression of the inverse FFT base distance was given.The relative importance of different compensation terms was studied in great detail. The concept of searching compensation was put forward. Results and Condclusion Dcm-△Dvimis the be distance of inverse FFT transformation, the effect caused by the distance △Dim on one-dimension profile is negligible, and the effect caused by the distance Dvim should not be neglected and must be compensated. 展开更多
关键词 MMW millimeter wave radar step frequency one-dimension distance profile velocity compensation
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Wave height measurement in the Taiwan Strait with a portable high frequency surface wave radar 被引量:5
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作者 ZHOU Hao ROARTY Hugh WEN Biyang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第1期73-78,共6页
As an important equipment for sea state remote sensing, high frequency surface wave radar (HFSWR) has received more and more attention. The conventional method for wave height inversion is based on the ratio of the ... As an important equipment for sea state remote sensing, high frequency surface wave radar (HFSWR) has received more and more attention. The conventional method for wave height inversion is based on the ratio of the integration of the second-order spectral continuum to that of the first-order region, where the strong external noise and the incorrect delineation of the first- and second-order Doppler spectral regions due to spectral aliasing are two major sources of errors in the wave height. To account for these factors, two more indices are introduced to the wave height estimation, i.e., the ratio of the maximum power of the second-or- der continuum to that of the Bragg spectral region (RSCB) and the ratio of the power of the second harmonic peak to that of the Bragg peak (RSHB). Both indices also have a strong correlation with the underlying wave height. On the basis of all these indices an empirical model is proposed to estimate the wave height. This method has been used in a three-months long experiment of the ocean state measuring and analyzing ra- dar, type S (OSMAR-S), which is a portable HFSWR with compact cross-loop/monopole receive antennas developed by Wuhan University since 2006. During the experiment in the Taiwan Strait, the significant wave height varied from 0 to 5 m. The significant wave heights estimated by the OSMAR-S correlate well with the data provided by the Oceanweather Inc. for comparison, with a correlation coefficient of 0.74 and a root mean square error (RMSE) of 0.77 m. The proposed method has made an effective improvement to the wave height estimation and thus a further step toward operational use of the OSMAR-S in the wave height extraction. 展开更多
关键词 wave height high frequency surface wave radar field experiment COMPARISON Taiwan Strait
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Vessel fusion tracking with a dual-frequency high-frequency surface wave radar and calibrated by an automatic identification system 被引量:3
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作者 ZHANG Hui LIU Yongxin +1 位作者 JI Yonggang WANG Linglin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第7期131-140,共10页
High-frequency surface wave radar(HFSWR) and automatic identification system(AIS) are the two most important sensors used for vessel tracking.The HFSWR can be applied to tracking all vessels in a detection area,wh... High-frequency surface wave radar(HFSWR) and automatic identification system(AIS) are the two most important sensors used for vessel tracking.The HFSWR can be applied to tracking all vessels in a detection area,while the AIS is usually used to verify the information of cooperative vessels.Because of interference from sea clutter,employing single-frequency HFSWR for vessel tracking may obscure vessels located in the blind zones of Bragg peaks.Analyzing changes in the detection frequencies constitutes an effective method for addressing this deficiency.A solution consisting of vessel fusion tracking is proposed using dual-frequency HFSWR data calibrated by the AIS.Since different systematic biases exist between HFSWR frequency measurements and AIS measurements,AIS information is used to estimate and correct the HFSWR systematic biases at each frequency.First,AIS point measurements for cooperative vessels are associated with the HFSWR measurements using a JVC assignment algorithm.From the association results of the cooperative vessels,the systematic biases in the dualfrequency HFSWR data are estimated and corrected.Then,based on the corrected dual-frequency HFSWR data,the vessels are tracked using a dual-frequency fusion joint probabilistic data association(JPDA)-unscented Kalman filter(UKF) algorithm.Experimental results using real-life detection data show that the proposed method is efficient at tracking vessels in real time and can improve the tracking capability and accuracy compared with tracking processes involving single-frequency data. 展开更多
关键词 vessel tracking high-frequency surface wave radar automatic identification system joint probabilistic data association unscented Kalman filter
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The Study of Single Station Inverting the Sea Surface Current by HF Ground Wave Radar Based on Adjoint Assimilation Technology 被引量:2
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作者 HAN Shuzong YANG Hua +1 位作者 XUE Wenhu WANG Xingchi 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第3期383-388,共6页
This paper introduces the assimilation technology in an ocean dynamics model and discusses the feasibility of inverting the sea surface current in the detection zone by assimilating the sea current radial velocity det... This paper introduces the assimilation technology in an ocean dynamics model and discusses the feasibility of inverting the sea surface current in the detection zone by assimilating the sea current radial velocity detected by single station HF ground wave radar in ocean dynamics model. Based on the adjoint assimilation and POM model, the paper successfully inverts the sea surface current through single station HF ground wave radar in the Zhoushan sea area. The single station HF radar inversion results are also compared with the bistatic HF radar composite results and the fixed point measured results by Annderaa current meter. The error analysis shows that acquisition of flow velocity and flow direction data from the single station HF radar based on adjoint assimilation and POM model is viable and the data obtained have a high correlation and consistency with the flow field observed by HF radar. 展开更多
关键词 ocean current HF ground wave radar inversion technology adjoint assimilation technology POM FVCOM
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Surface tidal currents in the open sea area to the east of the Zhoushan Islands measured with high frequency surface wave radar 被引量:3
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作者 SHEN Zhiben WU Xiongbin +2 位作者 FEI Yuejun XU Xing'an CHEN Xiaofeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第10期5-10,共6页
Based on the quasi-harmonic analysis of 11 d vector ocean currents obtained from two high frequency sur- face wave radars located at Zhujiajian Island and Shengshan Island, the spatial distribution characteristics of ... Based on the quasi-harmonic analysis of 11 d vector ocean currents obtained from two high frequency sur- face wave radars located at Zhujiajian Island and Shengshan Island, the spatial distribution characteristics of surface tidal currents in the open sea area to the east of the Zhoushan Islands of Zhejiang Province, China are studied. The following conclusions are drawn from the analysis: the tidal current pattern in the open sea area to the east of Zhoushan Islands is primarily regular semidiurnal, which is significantly affected by the shallow water constituents. The directions of the major axes of tidal current ellipses of M2 lie approx- imately in the NW-SE direction. With the increasing of distance away from the coast, the directions of the tidal current ellipses gradually shift toward the E-W direction. The tidal currents are mainly reversing cur- rents. The spatial distribution of probable maximum current velocities decreases gradually from northeast to southwest which is basically in accordance with the spatial distribution of measured maximum current velocities. The residual currents near the coast are larger than those far away from the coast. The directions of the residual currents are basically north by east, and the angle to the due north increases gradually with the increasing distance away from the coast. The topography shows a certain impact on the spatial distri- bution of shallow water constituents, the rotation of tidal currents, the probable maximum currents and the residual currents. 展开更多
关键词 high frequency surface wave radar quasi-harmonic analysis Zhoushan Islands of Zhejiang Province of China spatial distribution characteristics surface tidal currents
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Application of ESPRIT in Broad Beam HF Ground Wave Radar Sea Surface Current Mapping 被引量:1
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作者 LiuDan-hong WuXiong-bin WenBi-yang ChengFeng 《Wuhan University Journal of Natural Sciences》 CAS 2004年第2期209-214,共6页
HF surface wave radar system OSMAR2000 is a broad-beam sea-state detecting radar. ESPRIT (Estimation of Signal Parameters via Rotational Invariance Technique) algorithm is proposed to apply in DOA (direction of arriva... HF surface wave radar system OSMAR2000 is a broad-beam sea-state detecting radar. ESPRIT (Estimation of Signal Parameters via Rotational Invariance Technique) algorithm is proposed to apply in DOA (direction of arrival) determination of sea echoes. The algorithm of ESPRIT is briefly introduced first. Then discussions are made on the technique for application in the OSMAR2000 framework. Numerical simulation results are presented to demonstrate the feasibility of radial current mapping based on this method. The algorithm manifests significant performance and computational advantages compared with that of MUSIC. Data acquired by OSMAR2000 are processed to give radial current map and the synthesized vector currents are compared with the in-situ measurement with traditional means. The results show the validity of ESPRIT application in DOA determination for broad-beam radar. Key words HF ground wave radar - sea surface current - ESPRIT - MUSIC CLC number TN 911.72 - TN 958.95 Foundation item: Supported by the National Natural Science Foundation of China (60201003) and the National High Technology Development 863 Program of China (863-818-01-02)Biography: Liu Dan-hong (1976-), female, Master candidate, research direction: radar signal processing. 展开更多
关键词 HF ground wave radar sea surface current ESPRIT MUSIC
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Comparative analysis of single-and multiple-frequency thermal wave radar imaging inspection of glass fiber reinforced polymer(GFRP) 被引量:1
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作者 Lishuai Liu Andreas Mandelis +1 位作者 Alexander Melnikov Liming Wang 《International Journal of Extreme Manufacturing》 SCIE EI 2022年第2期161-172,共12页
Active infrared thermography has gained increasing popularity for nondestructive testing and evaluation in various industrial fields,especially for composite structures.In this regard,thermal wave radar(TWR)imaging is... Active infrared thermography has gained increasing popularity for nondestructive testing and evaluation in various industrial fields,especially for composite structures.In this regard,thermal wave radar(TWR)imaging is recognized as the next-generation active thermography technology to obtain great resolution and depth range over the inspected objects.A critical aspect concerns the optimal test parameter selection to guarantee reliable quality assurance required for industrial products.In this work,single-and multiple-frequency TWR was investigated in a quantitative manner with the goal of optimizing the detection parameters in terms of probing range and lateral and depth resolution.The effects of test parameters,including sampling frequency,modulation frequency,chirp duration,chirp bandwidth,etc,were investigated in detail through experiments on a glass fiber reinforced polymer specimen with multi-scale diameter-to-depth ratio defects.This paper aims to help yield a better understanding of the physical mechanism behind TWR and propose a workable scheme for testing parameter selection in practical applications. 展开更多
关键词 GFRP thermal wave radar testing parameters nondestructive testing
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FM interference suppression for PRC-CW radar based on adaptive STFT and time-varying filtering 被引量:9
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作者 Zhao Zhao Xiangquan Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期219-223,共5页
The influence of frequency modulation (FM) interfer- ence on correlation detection performance of the pseudo random code continuous wave (PRC-CW) radar is analyzed. It is found that the correlation output deterior... The influence of frequency modulation (FM) interfer- ence on correlation detection performance of the pseudo random code continuous wave (PRC-CW) radar is analyzed. It is found that the correlation output deteriorates greatly when the FM inter- ference power exceeds the anti-jamming limit of the radar. Accord- ing to the fact that the PRC-CW radar echo is a wideband pseudo random signal occupying the whole TF plane, while the FM in- terference only concentrates in a small portion, a new method is proposed based on adaptive short-time Fourier transform (STFT) and time-varying filtering for FM interference suppression. This method filters the received signal by using a binary mask to excise only the portion of the TF plane corrupted by the interference. Two types of interference, linear FM (LFM) and sinusoidal FM (SFM), under different signal-to-jamming ratio (S JR) are studied. It is shown that the proposed method can effectively suppress the FM interference and improve the performance of target detection. 展开更多
关键词 interference suppression frequency modulation in- terference adaptive short-time Fourier transform (STFT) time- varying filtering pseudo random code continuous wave (PRC-CW) radar.
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Range Ambiguity Elimination in a Short-Range FMCW Radar System 被引量:1
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作者 魏国华 吴嗣亮 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期201-204,共4页
Modified implementation architecture for sinusoidal frequency modulation is introduced to extract the range information from the received radar echo. Range ambiguity problem arises because the range is calculated from... Modified implementation architecture for sinusoidal frequency modulation is introduced to extract the range information from the received radar echo. Range ambiguity problem arises because the range is calculated from the estimated phase of the received signal which is wrapped into (0, 2π]. By integrating Doppler frequency shifts, the variation of range can be estimated and used as an auxiliary information to help eliminating the corresponding range ambiguity. The performance of the new technique is evaluated by simulations. The results show that this technique is robust to sever phase noise and can be used effectively for ambiguity elimination of the modified sinusoidal frequency modulated continuous wave radar. 展开更多
关键词 range ambiguity mitigation frequency modulated continuous wave radar Doppler frequency
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Echo recognition and correction for guided wave radar level based on adaptive LMS 被引量:1
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作者 MA Wen-gang WANG Xiao-peng TIAN Jun-wei 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第4期328-333,共6页
The radar echo signal of non-stationary and singular points usually contains false echoes,which affects the recognition and measurement of liquid level echo signal.In order to eliminate false echo interference and imp... The radar echo signal of non-stationary and singular points usually contains false echoes,which affects the recognition and measurement of liquid level echo signal.In order to eliminate false echo interference and improve the recognition and measurement accuracy of the liquid level gauge,a method of echo recognition and correction based on adaptive least mean square(LMS)is proposed.The short-time amplitude function and short-time zero crossing rate function are combined to recognize the echo signal.The weight vector iteration and updating weight coefficients are obtained by LMS method.The echo signal is recognized and the false echo interference is suppressed.The experimental results show that the level echo signal can be accurately recognized by this method,and level measurement accuracy can reach0.47%F.S.Compared with other denoising methods,adaptive LMS can keep the signal singularity characteristics while suppressing the noise.Moreover,it has better robustness. 展开更多
关键词 guided wave radar liquid level gauge least mean square (LMS) echo correction
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Adaptive digital self-interference cancellation based on fractional order LMS in LFMCW radar 被引量:6
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作者 LUO Yongjiang BI Luhao ZHAO Dong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期573-583,共11页
Adaptive digital self-interference cancellation(ADSIC)is a significant method to suppress self-interference and improve the performance of the linear frequency modulated continuous wave(LFMCW)radar.Due to efficient im... Adaptive digital self-interference cancellation(ADSIC)is a significant method to suppress self-interference and improve the performance of the linear frequency modulated continuous wave(LFMCW)radar.Due to efficient implementation structure,the conventional method based on least mean square(LMS)is widely used,but its performance is not sufficient for LFMCW radar.To achieve a better self-interference cancellation(SIC)result and more optimal radar performance,we present an ADSIC method based on fractional order LMS(FOLMS),which utilizes the multi-path cancellation structure and adaptively updates the weight coefficients of the cancellation system.First,we derive the iterative expression of the weight coefficients by using the fractional order derivative and short-term memory principle.Then,to solve the problem that it is difficult to select the parameters of the proposed method due to the non-stationary characteristics of radar transmitted signals,we construct the performance evaluation model of LFMCW radar,and analyze the relationship between the mean square deviation and the parameters of FOLMS.Finally,the theoretical analysis and simulation results show that the proposed method has a better SIC performance than the conventional methods. 展开更多
关键词 adaptive digital self-interference cancellation(ADSIC) linear frequency modulated continuous wave(LFMCW)radar fractional order least mean square(LMS)
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Transmission Properties of Radar Wave through Reentry Plasma Sheath 被引量:2
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作者 高正平 马兆国 +2 位作者 刘静 李仲平 张大海 《Journal of Electronic Science and Technology of China》 2007年第1期29-32,37,共5页
In this paper, by taking into account the coupling of the ionization of ablation gas and atmosphere, an electrons density distribution model is built. Using this model, the transmission properties of different polariz... In this paper, by taking into account the coupling of the ionization of ablation gas and atmosphere, an electrons density distribution model is built. Using this model, the transmission properties of different polarization radar wave through sheath are evaluated on the basis of the transmission matrix theory. Then, we discuss the effects of the electrons density, the added magnetic field, and the radar wave frequency on the transmission properties. As a result of this investigation, greater transmission power could be gained in order to efficiently shorten communication blackout, by reducing the electrons density or choosing proper added magnetic field and the frequency of the radar wave according to the different polarization form of the radar wave. 展开更多
关键词 communication blackout plasma sheath radar wave REENTRY transmigsion properties
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Scattering of Electromagnetic Waves by Drift Vortex in Plasma
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作者 王栋 陈银华 王舸 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第1期1-7,共7页
In a quasi-two-dimensional model, the scattering of incident ordinary electromag- netic waves by a dipole-electrostatic drift vortex is studied with first-order Born approximation. The distribution of the scattering c... In a quasi-two-dimensional model, the scattering of incident ordinary electromag- netic waves by a dipole-electrostatic drift vortex is studied with first-order Born approximation. The distribution of the scattering cross-section and total cross-section are evaluated analytically in different approximate conditions, and the physical interpretations are discussed. When the wavelength of incident wave is much longer than the vortex radius (kia〈〈1), it is found that the angle at which the scattering cross-section reaches its maxim depends significantly on the approximation of the parameters of the vortex used. It is also found that the total scattering cross-section has an affinitive relation with the parameters of the plasma, while it is irrelevant to the frequency of the incident wave in a wide range of parameters of the vortex. In a totally different range of parameters when incident wave is in the radar-frequency range (then kia 〈〈 1, the wavelength of incident wave is much shorter than the vortex radius), the numerical procedure is conducted with computer in order to obtain the distribution and the total expression of the scattering crosssection. Then it is found that the total scattering cross-section in the low frequency range is much larger than that in high frequency range, so the scattering is more effective in the low frequency range than in high frequency range. 展开更多
关键词 dipole-electrostatic drift vortex scattering of electromagnetic wave scattering cross-section radar wave
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Contrast validation test for retrieval method of high frequency ground wave radar
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作者 王海龙 郭佩芳 +2 位作者 韩树宗 谢强 周良明 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第1期22-28,共7页
In this paper, on the basis of the working principles of high frequency ground wave radar for retrieval of ocean wave and sea wind elements were used to systematically study the data obtained from contrast validation ... In this paper, on the basis of the working principles of high frequency ground wave radar for retrieval of ocean wave and sea wind elements were used to systematically study the data obtained from contrast validation test in Zhoushan sea area of Zhejiang Province on Oct. 2000, to validate the accuracy of OSMAR2000 for wave and wind parameters, and to analyze the possible error caused when using OSMAR2000 to retrieve ocean parameters. 展开更多
关键词 high frequency ground wave radar ocean wave sea wind contrast validation
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Estimation of detection threshold in multiple ship target situations with HF ground wave radar
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作者 Li Hongbo Shen Yiying Liu Yongtan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期739-744,共6页
A credible method of calculating the detection threshold is presented for the multiple target situations, which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave... A credible method of calculating the detection threshold is presented for the multiple target situations, which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave radar. This method defines a whole-peak-outlier elimination (WPOE) criterion, which is based on in-peak-samples correlation of each target echo spectra, to trim off the target signals and abnormal disturbances with great amplitude from the complex spectra. Therefore, cleaned background noise samples are obtained to improve the accuracy and reliability of noise level estimation. When the background noise is nonhomogeneous, the detection samples are limited and often occupied heavily with outliers. In this case, the problem that the detection threshold is overvalued can be solved. In applications on experimental data, it is verified that this method can reduce the miss alarm rate of signal detection effectively in multiple target situations as well as make the adaptability of the detector better. 展开更多
关键词 HF ground wave radar multiple target detection outlier elimination threshold estimation
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A Method for Improving Ranging Accuracy of Short-range Millimeter Wave Radar
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作者 吴礼 彭树生 +1 位作者 肖泽龙 是湘全 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第4期273-278,共6页
The range-velocity ambiguity caused by moving target influences on the ranging accuracy of a short-range millimeter wave radar greatly.A new method was presented in this paper to reduce the range-velocity ambiguity an... The range-velocity ambiguity caused by moving target influences on the ranging accuracy of a short-range millimeter wave radar greatly.A new method was presented in this paper to reduce the range-velocity ambiguity and improve the ranging accuracy by estimating parameters of the echo signal with fractional Fourier transform and self-correlation.And,a new quick searching algorithm was given also to increase the calculation speed.Compared to the Chinese remainder theorem method,the proposed method is excellent for its simplicity and reducing the computation complexity.The simulation results show its validity. 展开更多
关键词 radar engineering fraction Fourier transform short-range millimeter wave radar ranging accuracy
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