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Gravitation and the Unified Nature of All Kinds of Motion in Non-Empty Space (Part 1)
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作者 Yuri N. Ivanov Anton V. Pinchuk 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1918-1932,共15页
The presented work examines the mechanism and conditions of self-motion in bodies as systems of interacting elements. It is shown how the oscillation parameters of these elements determine the mode of motion of the sy... The presented work examines the mechanism and conditions of self-motion in bodies as systems of interacting elements. It is shown how the oscillation parameters of these elements determine the mode of motion of the system (body). In this case, the motion is considered as a consequence of symmetry breaking of forces in the systems themselves, and not as a reaction of individual elements to external influences. It is shown that such a violation takes place both in the gravitational field and when the system moves by inertia. Examples of the influence of changes in phase (φ) and frequency (f) parameters of the system elements on the velocity mode of its motion in space are considered. The identity of the causes of self-motion is revealed both in the case of gravitation and inertial motion. 展开更多
关键词 GRAVITATION SELF-motion phase Frequency Time Rate Standing Wave Potential Well Standing Wave Node MOMENTUM Quantity of motion
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MODIFIED CLT-DOMAIN MOTION ESTIMATION BASED ON PHASE CORRELATION 被引量:1
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作者 BiLingyan ChanKowkping YuYinglin 《Journal of Electronics(China)》 2004年第2期110-115,共6页
In this paper, a Modified Complex Lapped Transform domain Motion Estimation (MCLT-ME) method to estimate the motion of video sequence is proposed. The proposed method is based on phase correlation of current window re... In this paper, a Modified Complex Lapped Transform domain Motion Estimation (MCLT-ME) method to estimate the motion of video sequence is proposed. The proposed method is based on phase correlation of current window region and corresponding window region, and provides a significant improvement in motion estimation. 展开更多
关键词 Complex lapped transform phase correlation motion estimation
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A Hydrodynamic Model Including Phase Transition and the Thermal Motion Induced Transverse Momentum Distributions in p-p Collisions at LHC Energies
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作者 Zhijin Jiang Dongfang Xu Yu Zhang 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第1期20-30,共11页
It is widely believed that the matter created in p-p collisions exhibits a similar collective behavior as that formed in heavy ion collisions. In this paper, by taking into account the effects of thermal motion, the t... It is widely believed that the matter created in p-p collisions exhibits a similar collective behavior as that formed in heavy ion collisions. In this paper, by taking into account the effects of thermal motion, the transverse momentum distributions of identified charged particles are discussed in the scope of the hydrodynamic model including phase transition. The theoretical model gives a good description to the data collected in p-p collisions at LHC energies for the transverse momentum up to about . 展开更多
关键词 Thermal motion RELATIVISTIC Hydrodynamics phase Transition Transverse MOMENTUM Distribution
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Motion of a Nonrelativistic Quantum Particle in Non-commutative Phase Space
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作者 FATEME Hoseini 马凯 HASSAN Hassanabadi 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期5-8,共4页
The equation governing the motion of a quantum particle is considered in nonrelativistic non-commutative phase space. For this aim, we first study new Poisson brackets in non-commutative phase space and obtain the mod... The equation governing the motion of a quantum particle is considered in nonrelativistic non-commutative phase space. For this aim, we first study new Poisson brackets in non-commutative phase space and obtain the modified equations of motion. Next, using novel transformations, we solve the equation of motion and report the exact analytical solutions. 展开更多
关键词 motion of a Nonrelativistic Quantum Particle in Non-commutative phase Space NCS
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Stability of Motion "In the Large" of Some Class of Phase Systems
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作者 M.N.Kalimoldayev L.S.Kopbosyn A.A.Abdildayeva T.Duzbayev M.Akhmetzhanov 《Journal of Mathematics and System Science》 2015年第3期118-121,共4页
This article focuses on the study of stability of motion of the phase systems described by differential equations whose right-hand sides are periodic in the angular coordinate. The article deals with the mathematical ... This article focuses on the study of stability of motion of the phase systems described by differential equations whose right-hand sides are periodic in the angular coordinate. The article deals with the mathematical model which has been investigated for stability "in the large" using the second Lyapunov method. Based on the theoretical results obtained in the work,the computational experiments on concrete examples of electric power systems, which showedthe sufficient efficacy of the proposed method for the studied phase system, were conducted. 展开更多
关键词 Stability of motion in the large" Lyapunov function phase system electric power system mathematical model.
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ISAR MOTION COMPENSATION USING ROPE 被引量:5
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作者 汪玲 朱兆达 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期64-68,共5页
Motion compensation is a key step for inverse synthetic aperture radar (ISAR) imaging. Many algorithms have been proposed. The rank one phase estimation (ROPE) algorithm is a good estimator for phase error widely used... Motion compensation is a key step for inverse synthetic aperture radar (ISAR) imaging. Many algorithms have been proposed. The rank one phase estimation (ROPE) algorithm is a good estimator for phase error widely used in SAR. The ROPE algorithm is used in ISAR phase compensation and the concrete implementation steps are presented. Subsequently, the performance of ROPE is analyzed. For ISAR data that fit the ROPE algorithm model, an excellent compensation effect can be obtained with high computation efficiency. Finally, ISAR real data are processed with ROPE and its imaging result is compared with that obtained by the modified Doppler centroid tracking (MDCT) method, which is a robust and good estimator in ISAR phase compensation. 展开更多
关键词 inverse synthetic aperture radar (ISAR) motion compensation phase compensation rank one phase estimation (ROPE)
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A NEW CRITERION FOR OCCURRENCE OF STICK-SLIP MOTION IN DRIVE MECHANISM 被引量:2
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作者 丁文镜 樊世超 陆明万 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2000年第3期273-281,共9页
This paper, using Karnopp's model of friction force and phase plane method, studies the stick-slip motion of the flexible drive mechanism. It is explained that a sudden drop of friction force is the essential sour... This paper, using Karnopp's model of friction force and phase plane method, studies the stick-slip motion of the flexible drive mechanism. It is explained that a sudden drop of friction force is the essential source of stick-slip motion when the sliding is impending. A new criterion for occurrence of stick-slip motion is established. The stick-slip region and the stable region in a parameter plane are separated by a critical parameter curve. Moreover, for the stick-slip motion of the flexible drive mechanism without viscous damping, a parameter expression is obtained. The results may be used in design of the flexible drive mechanism. 展开更多
关键词 FRICTION phase plane stick-slip motion parameter criterion
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ON EQUATION OF DISCRETE SOLID PARTICLES' MOTION IN ARBITRARY FLOW FIELD AND ITS PROPERTIES 被引量:2
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作者 黄社华 李炜 程良骏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第3期297-310,共14页
The forces on rigid particles moving in relation to fluid having been studied and the equation of modifications of their expressions under different flow conditions discussed, a general form of equation for discrete p... The forces on rigid particles moving in relation to fluid having been studied and the equation of modifications of their expressions under different flow conditions discussed, a general form of equation for discrete particles' motion in arbitrary flow field is obtained. The mathematical features of the linear form of the equation are clarified and analytical solution of the linearized equation is gotten by means of Laplace transform. According to above theoretical results, the effects of particles' properties on its motion in several typical flow field are studied, with some meaningful conclusions being reached. 展开更多
关键词 solid liquid two phase flow discrete particles' motion equation discrete solid particles Laplace transform
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Non-cooperative Space Target Estimation Algorithm Without Prior Information Dependence Based on Temporal Line of Sight Constraint
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作者 XIAO Hui ZHU Chongrui +3 位作者 LIU Xinqi YU Yifan SHENG Qinghong YANG Rui 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期526-540,共15页
Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a p... Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning. 展开更多
关键词 motion parameter estimation estimation of impact point infrared early warning boost phase modeling trajectory database construction
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MOTION COMPENSATION USING SUBSTRIP PGA 被引量:1
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作者 Zhang Lei Liu Yabo Yang Liang 《Journal of Electronics(China)》 2014年第4期317-324,共8页
MOtion COmpensation(MOCO) is an essential step in high resolution airborne Synthetic Aperture Radar(SAR) imaging. Generally, a reference altitude level is assumed and external Digital Elevation Model(DEM) is required ... MOtion COmpensation(MOCO) is an essential step in high resolution airborne Synthetic Aperture Radar(SAR) imaging. Generally, a reference altitude level is assumed and external Digital Elevation Model(DEM) is required for the scene topography heavily varied. To overcome the shortcoming, we propose a MOCO method based on Phase Gradient Autofocus(PGA) which can obtain well focused images without DEM. In the implementation, we first compensate the normal range-invariant term. Then the data are divided into strips in range-compressed domain and PGA is applied to each substrip to extract the phase errors. Finally, the phase error surface is obtained using interpolation and then compensated. Real airborne SAR data of a UAV-SAR system experiments and comparisons demonstrate the validity and effectiveness of the proposed algorithm. The results show that our algorithm is effective. 展开更多
关键词 Synthetic Aperture Radar (SAR) motion COmpensation (MOCO) phase Gradient Autofocus (PGA)CLC number:TN957.52
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Phase-Division-Based Dynamic Optimization of Linkages for Drawing Servo Presses 被引量:4
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作者 Zhi-Gang Zhang Li-Ping Wang Yan-Ke Cao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1426-1437,共12页
Existing linkage-optimization methods are designed for mechanical presses; few can be directly used for servo presses, so development of the servo press is limited. Based on the complementarity of linkage opti- mizati... Existing linkage-optimization methods are designed for mechanical presses; few can be directly used for servo presses, so development of the servo press is limited. Based on the complementarity of linkage opti- mization and motion planning, a phase-division-based linkage-optimization model for a drawing servo press is established. Considering the motion-planning principles of a drawing servo press, and taking account of work rating and efficiency, the constraints of the optimization model are constructed. Linkage is optimized in two modes: use of either constant eccentric speed or constant slide speed in the work segments. The performances of optimized link- ages are compared with those of a mature linkage SL4- 2000A, which is optimized by a traditional method. The results show that the work rating of a drawing servo press equipped with linkages optimized by this new method improved and the root-mean-square torque of the servo motors is reduced by more than 10%. This research pro- vides a promising method for designing energy-saving drawing servo presses with high work ratings. 展开更多
关键词 Drawing servo press Linkage optimization phase-division motion planning
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CPG Human Motion Phase Recognition Algorithm for a Hip Exoskeleton with VSA Actuator
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作者 Jiaxuan Li Feng Jiang +6 位作者 Longhai Zhang Xun Wang Jinnan Duan Baichun Wei Xiulai Wang Ningling Ma Yutao Zhang 《Journal of Signal and Information Processing》 2024年第2期19-59,共41页
Due to the dynamic stiffness characteristics of human joints, it is easy to cause impact and disturbance on normal movements during exoskeleton assistance. This not only brings strict requirements for exoskeleton cont... Due to the dynamic stiffness characteristics of human joints, it is easy to cause impact and disturbance on normal movements during exoskeleton assistance. This not only brings strict requirements for exoskeleton control design, but also makes it difficult to improve assistive level. The Variable Stiffness Actuator (VSA), as a physical variable stiffness mechanism, has the characteristics of dynamic stiffness adjustment and high stiffness control bandwidth, which is in line with the stiffness matching experiment. However, there are still few works exploring the assistive human stiffness matching experiment based on VSA. Therefore, this paper designs a hip exoskeleton based on VSA actuator and studies CPG human motion phase recognition algorithm. Firstly, this paper puts forward the requirements of variable stiffness experimental design and the output torque and variable stiffness dynamic response standards based on human lower limb motion parameters. Plate springs are used as elastic elements to establish the mechanical principle of variable stiffness, and a small variable stiffness actuator is designed based on the plate spring. Then the corresponding theoretical dynamic model is established and analyzed. Starting from the CPG phase recognition algorithm, this paper uses perturbation theory to expand the first-order CPG unit, obtains the phase convergence equation and verifies the phase convergence when using hip joint angle as the input signal with the same frequency, and then expands the second-order CPG unit under the premise of circular limit cycle and analyzes the frequency convergence criterion. Afterwards, this paper extracts the plate spring modal from Abaqus and generates the neutral file of the flexible body model to import into Adams, and conducts torque-stiffness one-way loading and reciprocating loading experiments on the variable stiffness mechanism. After that, Simulink is used to verify the validity of the criterion. Finally, based on the above criterions, the signal mean value is removed using feedback structure to complete the phase recognition algorithm for the human hip joint angle signal, and the convergence is verified using actual human walking data on flat ground. 展开更多
关键词 Variable Stiffness Actuator Plate Spring CPG Algorithm Convergence Criterion Human motion phase Recognition Simulink and Adams Co-Simulation
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Averaging Analysis of Self-Excited Motion of a Quasi-Axisymmetrical Gyrostat
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作者 薛纭 陈立群 《Journal of Shanghai University(English Edition)》 CAS 2002年第2期125-129,共5页
The averaging analysis was carried out to study the motion of a quasi axisymmetrical gyrostat under a small magnitude self excited control torque. The common approach to investigating the problem of rigid body rot... The averaging analysis was carried out to study the motion of a quasi axisymmetrical gyrostat under a small magnitude self excited control torque. The common approach to investigating the problem of rigid body rotation under the action of a small torque known in the body frame was described. Using this approach, the problem (Grammel's problem for the case of small torque) that is maintaining the angular velocity of a quasi axisymmetrical gyrostat using a control torque quadratic in the angular velocity was solved. 展开更多
关键词 GYROSTAT self excited motion averaging method phase trajectories.
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Characterization of a 3-Phase a.c. Free Burning Arc Plasma 被引量:1
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作者 夏维东 Laurent FULCHERI +2 位作者 Jose GONZALEZ-AGUILAR 李辉 Thomas M. GRUENBERGER 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第2期156-163,共8页
A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed ... A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed neutral point. This gives rise to a rich and complex phenomenology related to instabilities and arc motion since the arcs are "burning" freely in the gas flow between the three electrodes. This paper is dedicated to the analysis of the behavior of such a system under typical conditions using argon and nitrogen as plasma gases. A classification of are configuration, arc commutating, arc interaction, arc motion and arc instabilities are discussed based on ultra high-speed cine camera analysis. A simple model describing the time evolution of the system is also presented and compared with the experimental measurements. The results show that an adequate control could allow the improvement of the overall system. 展开更多
关键词 3-phase AC arc plasma free arc arc motion arc commutating arc instabilities
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A Novel Method with Martingale Theory for Phase Noise Analysis in Coherent Optical Communication
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作者 Chengle Sui Qiangmin Wang +1 位作者 Shilin Xiao Pingqing Li 《Optics and Photonics Journal》 2013年第2期171-174,共4页
Phase noise has a great influence on the performance of coherent optical communication. In this paper, martingale theory is introduced to analyze the phase noise effect for the first time as far as we know. Through Fu... Phase noise has a great influence on the performance of coherent optical communication. In this paper, martingale theory is introduced to analyze the phase noise effect for the first time as far as we know. Through Fubini’s Theory and martingale representation theory, we proved that , which denotes the phase noise effect, is a predictable martingale. Then Ito’s formula for solution to stochastic differential equation is utilized for the analysis of phase noise effect. Using our method, a nonrecursive formula for the moments of phase noise is derived and signal-noise-ratio (SNR) degradation in coherent optical OFDM due to phase noise is calculated with our method. 展开更多
关键词 MARTinGALE BROWNIAN motion Ito Itegral DERIVATION of MOMENTS phase Noise
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A Case Study on the Effect of Post-critical SmS on Ground Motion in Yingjiang,Yunnan Province,China
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作者 Luo Yan Ni Sidao Chen Yong 《Earthquake Research in China》 2011年第1期1-12,共12页
There are controversies on ground motion attenuation relations at the epicentral distance of about 100km. Some models predict that the seismic energy remains almost constant or becomes even stronger with increasing di... There are controversies on ground motion attenuation relations at the epicentral distance of about 100km. Some models predict that the seismic energy remains almost constant or becomes even stronger with increasing distance at this distance, while other models hold that it decreases with increased distance. The divergence lies mainly in whether SmS is stronger than direct S and surface waves at this distance. With the MsS. 9 earthquake sequence in the Yingjiang region of Yunnan Province as an example, we demonstrate that SmS is always 2 - 5 times stronger than direct S waves around the epicentral distance of 100km (which is the post-critical distance for S in this region). Study of synthetic seismograms suggest that crustal structure has an important effect on the amplitude of post-critical SmS, with simple crust producing strong SmS. This preliminary study confirms that in China, SmS also plays an important role on ground motion at distances around 100km, which demands more studies of post-critical SmS. 展开更多
关键词 SmS phase Strong ground motion Yingjiang area
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Including Planet 9 in the Solar System Increases the Coherence between the Sunspot Number Record and Solar Inertial Motion
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作者 Ian Edmonds 《International Journal of Astronomy and Astrophysics》 2022年第3期212-246,共35页
The Sun would be subject to a significant variation of orbital motion about the solar system barycentre if a small planet is orbiting at a very large distance. This paper assesses if the Planet 9 hypothesis, the exist... The Sun would be subject to a significant variation of orbital motion about the solar system barycentre if a small planet is orbiting at a very large distance. This paper assesses if the Planet 9 hypothesis, the existence of a ninth planet, is consistent with the planetary hypothesis: the synchronisation of sunspot emergence to solar inertial motion (SIM) induced by the planets. We show that SIM would be profoundly affected if Planet 9 exists and that the hypothesised effect of SIM on sunspot emergence would be radically different from the effect of SIM due to the existing eight planets. We compare the frequency and time variation of Sun to barycentre distance, R<sub>B</sub>, calculated for both the eight and nine planet systems, with the frequency and time variation of sunspot number (SSN). We show that including Planet 9 improves the coherence between R<sub>B</sub> and SSN in the decadal, centennial and millennial time range. Additionally, as the variation of R<sub>B </sub>is sensitive to the longitude and period of Planet 9, it is possible to adjust both parameters to fit the variation of R<sub>B</sub> to the SSN record and obtain new estimates of the period and present longitude of Planet 9. Finally, we develop the hypothesis that planetary induced solar acceleration reduces meridional flow and consequently sunspot emergence thereby providing an explanation for the observed coincidence of grand solar minima with intervals of extreme solar acceleration. 展开更多
关键词 Planet 9 Hypothesis Planetary Hypothesis Solar inertial motion Reconstructed Sunspot Number phase Modulation of SSN Future SSN Events
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机载双天线InSAR运动补偿误差的影响分析 被引量:12
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作者 李芳芳 仇晓兰 +2 位作者 孟大地 胡东辉 丁赤飚 《电子与信息学报》 EI CSCD 北大核心 2013年第3期559-567,共9页
干涉SAR运动补偿是实现高精度机载干涉SAR测量的关键。该文针对运动补偿误差对机载双天线干涉SAR测量的影响进行了详细的分析。首先在参考高程无误差和有误差两种情况下对运动补偿残余误差进行建模;随后分析了无测量误差条件下运动补偿... 干涉SAR运动补偿是实现高精度机载干涉SAR测量的关键。该文针对运动补偿误差对机载双天线干涉SAR测量的影响进行了详细的分析。首先在参考高程无误差和有误差两种情况下对运动补偿残余误差进行建模;随后分析了无测量误差条件下运动补偿残余误差对干涉相位和平面定位精度的影响;接着分析了存在航迹测量误差和基线测量误差条件下运动补偿残余误差的影响;最后,通过仿真和实测数据实验验证了理论推导的正确性。该文的分析结果为机载双天线干涉SAR系统设计和数据处理提供了理论基础。 展开更多
关键词 机载inSAR 运动补偿 残余误差 干涉相位 平面定位
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基于BP算法和时变基线的机载InSAR数据处理方法研究 被引量:5
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作者 潘舟浩 李道京 +1 位作者 刘波 张清娟 《电子与信息学报》 EI CSCD 北大核心 2014年第7期1585-1591,共7页
该文首先系统分析了传统机载InSAR数据处理方法由于波束中心近似和地形高程未知导致的相位误差问题,以及该相位误差对成像质量和高程精度造成的影响。其次,提出了基于BP算法和时变基线的机载InSAR数据处理方法,解决了波束中心近似带来... 该文首先系统分析了传统机载InSAR数据处理方法由于波束中心近似和地形高程未知导致的相位误差问题,以及该相位误差对成像质量和高程精度造成的影响。其次,提出了基于BP算法和时变基线的机载InSAR数据处理方法,解决了波束中心近似带来的问题,并通过时变基线的干涉处理方法减小了地形高程未知导致的高程误差。最后,通过仿真分析验证了该方法的有效性。 展开更多
关键词 干涉合成孔径雷达 运动补偿 后向投影算法 时变基线 相位误差
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InISAR三维成像中的ISAR像失配准分析及其补偿方法 被引量:10
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作者 罗斌凤 张群 +1 位作者 袁涛 张守宏 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2003年第6期739-743,共5页
在InISAR成像中,形成干涉的两天线在成像积累时间内所接收信号彼此存在波程差,引起了两ISAR像的失配,降低了三维成像效果.文中重点分析了两ISAR像的干涉波程差与目标运动参数间的关系,推导了失配准量与三维运动参数间的关系式.通过对计... 在InISAR成像中,形成干涉的两天线在成像积累时间内所接收信号彼此存在波程差,引起了两ISAR像的失配,降低了三维成像效果.文中重点分析了两ISAR像的干涉波程差与目标运动参数间的关系,推导了失配准量与三维运动参数间的关系式.通过对计算得到的目标散射中心的时变曲线的拟合估计出目标三维运动参数,进而补偿失配准量,完成成像.仿真效果表明该处理方法有效. 展开更多
关键词 inISAR 三维成像 干涉 像失配 失配准量 运动补偿 逆合成孔径雷达
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