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INERTIAL INTEGRATED SYSTEM OF NORTH SEEKING/SIGHT STABILIZING ON VEHICLE 被引量:2
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作者 刘建业 徐珍 +1 位作者 杨莉 肖纪立 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期157-162,共6页
A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relat... A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relative control circuits to make its function of North seeking possible. Double position calculation is adopted in this method, and by alignment at two sites the azimuth angle can be figured out. Also the orientation and the horizontal shifts of the gyro are simultaneously measured and compensated so as to improve the accuracy of north seeking. The system can automatically seek north when the vehicle is immobile. And the time consumption is no more than 5.5 min. Besides, the system can keep azimuth angle and provide tilt angle and pitch angle of the vehicle. 展开更多
关键词 north seeking sight stabilizing inertial platform shift measurement and compensation land fighting vehicle
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基于ISIGHT圆柱绕流的换热强化与减阻优化设计 被引量:1
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作者 赖海清 张东辉 +1 位作者 陈宁 石珊 《舰船科学技术》 北大核心 2015年第1期93-97,共5页
圆柱绕流在工程应用中十分普遍,大到海洋结构物,小到微型换热器均有其身影,其中控制圆柱的排布对主圆柱的最终性能有着举足轻重的影响。为研究圆柱绕流系统的换热强度及减阻性能,本文利用ISIGHT优化平台强大的集成能力,实现利用ISIGHT驱... 圆柱绕流在工程应用中十分普遍,大到海洋结构物,小到微型换热器均有其身影,其中控制圆柱的排布对主圆柱的最终性能有着举足轻重的影响。为研究圆柱绕流系统的换热强度及减阻性能,本文利用ISIGHT优化平台强大的集成能力,实现利用ISIGHT驱动Gambit,Fluent软件并寻求最优参数组合的设计流程。研究发现,在Re=200时,与单圆柱系统相比,通过合理布置控制圆柱的方位参数(间隙率L/D=2,夹角degree=30°时),在提高换热性能的同时,还能减小圆柱阻力的优良结构。全程采用参数化设计,自动化寻优,提高了设计效率,为圆柱绕流提供了一个新的优化思路。 展开更多
关键词 圆柱绕流 优化设计 换热 Isight
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基于iSIGHT集成技术的某重卡双轴转向机构多目标优化 被引量:2
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作者 周红妮 冯樱 +1 位作者 赵慧勇 朱林 《汽车零部件》 2015年第6期26-30,共5页
针对东风某重卡汽车在使用中存在的轮胎异常磨损问题,利用ADAMS/View对双轴转向机构进行建模与运动学仿真。基于多学科设计优化(MDO)软件i SIGHT,实现ADAMS/View运动学仿真集成,并建立机构优化分析流程。采用正交数组DOE分析法和NSGA-I... 针对东风某重卡汽车在使用中存在的轮胎异常磨损问题,利用ADAMS/View对双轴转向机构进行建模与运动学仿真。基于多学科设计优化(MDO)软件i SIGHT,实现ADAMS/View运动学仿真集成,并建立机构优化分析流程。采用正交数组DOE分析法和NSGA-II遗传算法实现了该双轴转向机构的多目标优化。优化结果表明:优化后各车轮转角误差大大减小,有效解决了车轮异常磨损问题。 展开更多
关键词 双轴转向机构 i sight集成 ADAM/View运动仿真 遗传算法 多目标优化
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基于iSIGHT平台的剖面几何参数对剖面性能的影响
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作者 黄斌 熊鹰 王波 《船海工程》 北大核心 2016年第4期28-32,共5页
为提高水翼抗空化性能,设计出具有较好空泡性能的翼型剖面,基于i SIGHT优化平台,集成翼剖面水动力性能的面元法理论预报程序,采用试验设计方法(DOE)构建剖面几何参数对翼剖面性能的响应面模型,分析剖面各几何参数对剖面空泡性能的影响... 为提高水翼抗空化性能,设计出具有较好空泡性能的翼型剖面,基于i SIGHT优化平台,集成翼剖面水动力性能的面元法理论预报程序,采用试验设计方法(DOE)构建剖面几何参数对翼剖面性能的响应面模型,分析剖面各几何参数对剖面空泡性能的影响。结果表明,增大剖面的最大拱度,最大厚度向导缘移动,最大拱度向尾缘移动以及减小攻角均有利于提高剖面的水动力性能;增加剖面的最大厚度能改善剖面的空泡性能,但剖面最大厚度一般根据剖面强度要求确定。 展开更多
关键词 面元法 I sight优化平台 空泡性能
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Review Paper on the Studies of Sight Translation and Sight Interpreting
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作者 陈淑娴 《海外英语》 2021年第8期84-85,共2页
Sight Translation is regarded as an indispensable skill prior to the study of Simultaneous Interpreting.And Sight Interpreting is employed in some settings like court interpreting and formal conferences.The importance... Sight Translation is regarded as an indispensable skill prior to the study of Simultaneous Interpreting.And Sight Interpreting is employed in some settings like court interpreting and formal conferences.The importance of studying Sight Translation and Sight Interpreting is apparent.This paper reviews the previous literatures on the studies of Sight Translation and Sight Interpreting in the West and in China over the past four decades for attaining a full picture on the studies in this field.This paper focuses on the function and significance of studying Sight Translation and Sight Interpreting from both home and abroad. 展开更多
关键词 sight Translation sight Interpreting Effort Models
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基于In-Sight小型环形工件尺寸测量研究 被引量:1
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作者 张伟建 杨星 彭湃 《信息化研究》 2022年第1期25-29,共5页
小型环形工件是许多行业常常使用的工件类型,其尺寸对环形工件的质量把控来说非常重要,如今大部分环形工件内外径的测量依然还停留在人工使用仪器仪表进行手动检测的层面,检测效率低下,也容易造成误差。借助视觉检测来取代小型环形工件... 小型环形工件是许多行业常常使用的工件类型,其尺寸对环形工件的质量把控来说非常重要,如今大部分环形工件内外径的测量依然还停留在人工使用仪器仪表进行手动检测的层面,检测效率低下,也容易造成误差。借助视觉检测来取代小型环形工件的人工检测已成为一个急需要解决的问题。但是,目前视觉检测项目的开发往往仅限于项目产品本身,需要对每个产品进行专门的高级语言编写,开发过程长、开发成本较高,开发平台不具备同类包容性。针对以上特点,文章采用康耐视In-Sight软件作为图像检测开发平台,介绍一种智能相机的视觉检测快速开发方法,开发函数设置便捷、开发周期短、开发工作量小的小型环形工件视觉检测系统。文章采用多组实验验证系统精度,为精度等级处于T15-T18的环型产品快速开展尺寸检测提供视觉解决方案。 展开更多
关键词 图像检测 环形工件 IN-sight
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Line-of-Sight MIMO for Next-Generation Microwave Transmission Systems
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作者 Xianwei Gong Zhifeng Yuan +1 位作者 Jun Xu Liujun Hu 《ZTE Communications》 2012年第4期33-38,共6页
Line-of-sight MIMQ (LoS MIMO) is not applicable in scattering wireless transmission scenarios, but it may be applied in LoS microwave transmission scenarios if antenna spacing (within transmit and/or receive arrays... Line-of-sight MIMQ (LoS MIMO) is not applicable in scattering wireless transmission scenarios, but it may be applied in LoS microwave transmission scenarios if antenna spacing (within transmit and/or receive arrays) is suitable and there is one hop distance. LoS MIMQ can improve channel capacity and performance of a transmission system. In this paper, we discuss factors affecting channel capacity and performance in LoS MIMO. We also discuss the feasibility LoS MIMO applications. 展开更多
关键词 line of sight MIMO MICROWAVE channel capacity
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Locating the position of objects in non-line-of-sight based on time delay estimation
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作者 王雪峰 王元庆 +1 位作者 苏金善 杨兴雨 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期163-169,共7页
Non-line-of-sight imaging detection is to detect hidden objects by indirect light and intermediary surface(diffuser).It has very important significance in indirect access to an object or dangerous object detection, ... Non-line-of-sight imaging detection is to detect hidden objects by indirect light and intermediary surface(diffuser).It has very important significance in indirect access to an object or dangerous object detection, such as medical treatment and rescue. An approach to locating the positions of hidden objects is proposed based on time delay estimation. The time delays between the received signals and the source signal can be obtained by correlation analysis, and then the positions of hidden objects will be located. Compared with earlier systems and methods, the proposed approach has some modifications and provides significant improvements, such as quick data acquisition, simple system structure and low cost, and can locate the positions of hidden objects as well: this technology lays a good foundation for developing a practical system that can be used in real applications. 展开更多
关键词 NON-LINE-OF-sight time delay estimation CROSS-CORRELATION hidden object location
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In—Sight视觉传感器用软件
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《电子产品世界》 2004年第03B期103-103,共1页
关键词 视觉传感器 Cognex Corporation公司 In—sight EXPLORER软件
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Netro-非视距(Non Line Of Sight)固定无线架构的灵活性
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《无线电工程》 2002年第11期60-61,共2页
成功地部署一个固定宽带无线(FBW)网络取决于两个关键因素:射频网络规划的灵活性和视距(LOS)/非视距(NLOS)情况。因为在视距(LOS)情况下要求在发射机和接收器之间没有阻挡,运营商在规划和部署一个视距(LOS)的固定宽带无线(FBW)网络... 成功地部署一个固定宽带无线(FBW)网络取决于两个关键因素:射频网络规划的灵活性和视距(LOS)/非视距(NLOS)情况。因为在视距(LOS)情况下要求在发射机和接收器之间没有阻挡,运营商在规划和部署一个视距(LOS)的固定宽带无线(FBW)网络时,需面对许多技术和业务上的困难;事实上第…… 展开更多
关键词 非视距 Netro Non Line Of sight NLOS 频率复用 自适应调制 蜂窝
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Chinese Companies Set Sights on Asia-Pacific Oil Assets
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作者 Fu Hong 《China Oil & Gas》 CAS 2017年第1期61-66,共6页
Fossil fuels may be out of fashion,but sales of foreignowned resources across Asia are expected to attract a broad mix of bidders.Some of Asia’s biggest foreignowned oil and gas assets,worth more than US$40 billion,a... Fossil fuels may be out of fashion,but sales of foreignowned resources across Asia are expected to attract a broad mix of bidders.Some of Asia’s biggest foreignowned oil and gas assets,worth more than US$40 billion,are to be sold in 2017,with potential bidders expected to include Chinese energy companies and sovereign funds.Assets to be sold include US-based Chevron’s US$1billion(0.94 billion euros)joint ownership stake with China’s state-owned CNOOC in an offshore oil field. 展开更多
关键词 ASIA Chinese Companies Set sights on Asia-Pacific Oil Assets US than
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Isight环境下基于视轴抖动误差的镜头结构优化 被引量:3
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作者 杨丰福 田海英 +2 位作者 颜昌翔 吴从均 母德强 《红外与激光工程》 EI CSCD 北大核心 2019年第1期223-230,共8页
为了在机载振动环境下获得满足光学性能指标要求的偏振成像光谱仪镜头的最佳结构性能,建立了基于视轴抖动误差的优化模型,并在Isight集成优化环境下对该模型进行了求解。首先,阐述了视轴抖动误差影响光学系统性能的原理并根据光学系统... 为了在机载振动环境下获得满足光学性能指标要求的偏振成像光谱仪镜头的最佳结构性能,建立了基于视轴抖动误差的优化模型,并在Isight集成优化环境下对该模型进行了求解。首先,阐述了视轴抖动误差影响光学系统性能的原理并根据光学系统模型和指标需求设计了镜头的初始结构;其次,推导了视轴抖动误差的计算方法并建立了基于视轴抖动误差的优化模型;最后,在Isight环境下,使用多岛遗传算法对优化模型进行了求解。结果表明:在满足镜头视轴抖动误差的要求下,镜筒质量降低了17.4%,镜头光学系统传函为0.4(77 lp/mm),满足设计指标要求。提出的优化方法引入镜头视轴抖动误差作为优化约束,拓展了光机结构优化的内涵,为同类结构的优化提供了新的思路。 展开更多
关键词 视轴抖动误差 光机结构优化 光学系统传递函数 集成优化
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Effect of Sight Translation on Consecutive Interpreting and Teaching Strategies
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作者 杨柳 《海外英语》 2015年第4期139-141,共3页
Sight Translation(ST) has long been considered as a useful exercise for acquiring interpreting skills. However, little studies have been done to prove how the skills acquired from ST can be transferred to other modes ... Sight Translation(ST) has long been considered as a useful exercise for acquiring interpreting skills. However, little studies have been done to prove how the skills acquired from ST can be transferred to other modes of interpreting, for instance,Consecutive Interpreting(CI). In this study, the sequencing of ST and CI teaching is explored to proof that starting ST teaching first is more logical. Gile's effort model is used to explain the similarities and differences of ST and CI and to set up possible effect of ST on CI. Some teaching strategies of transferring ST skills to CI are proposed. 展开更多
关键词 sight TRANSLATION consecutive INTERPRETING TEACHING STRATEGIES
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An Empirical Study of Students' Sight Translation Practice
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作者 孙佳妮 《海外英语》 2012年第7X期147-149,共3页
Most of the studies on sight translation are related to analyzing effort models.Some scholars have established effort models for interpreting activities.However,the majority of the research published in English was co... Most of the studies on sight translation are related to analyzing effort models.Some scholars have established effort models for interpreting activities.However,the majority of the research published in English was conducted between English and European languages.Experiments written in English on interpreting between English and Chinese are limited.The purpose of this research is to explore the problems that occurred in students'performance of sight translation with a view to improving students'performance and the training method.The results of the experiment show that ST skills are composed of two parts:linguistic capacity and delivery skills.The problems that occurred in the case study were presented as delivery problems.However,the reason for the problems was lack of linguistic transfer capacity.This study recommends that students should be trained both on linguistic capacity and delivery skills. 展开更多
关键词 INTERPRETING TRANSLATION sight TRANSLATION EFFORT
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A Study of Zhang Peiji ' s English Version of The Sight of Father's Back
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作者 曾凡梅 《海外英语》 2018年第1期188-189,共2页
Mr.zhang peiji, a translator of The Sight of Father's Back, is a famous modern Chinese translation theorist and translator.He has made a great contribution to both translation theory and translation practice. His ... Mr.zhang peiji, a translator of The Sight of Father's Back, is a famous modern Chinese translation theorist and translator.He has made a great contribution to both translation theory and translation practice. His translation practice includes fictions, dramas, biography and essays. This paper is an attempt to make a study of Zhang Peiji's English version of The Sight of Father's Back. 展开更多
关键词 Zhang Peiji The sight of Father’s Back TRANSLATION
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Fabrication Technique of Holographic Sight
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作者 林凌 刘守 张向苏 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第1期105-108,共4页
There are several types of sights used for small arms. All of them have advantages and disadvantages. A new type of sight-holographic sight-is introduced in the paper, with the emphasis on the fabrication technique of... There are several types of sights used for small arms. All of them have advantages and disadvantages. A new type of sight-holographic sight-is introduced in the paper, with the emphasis on the fabrication technique of the hologram which is the most important part in the sight. A Gaussian dot and a reticle pattern are recorded in the hologram. When illuminated by a laser diode, the virtual images of the dot and the reticle pattern for aiming are observed through the hologram. Compared with other sights, the holographic sight provides quicker, more accurate and covert aiming at moving targets, particularly in close quarter combat situations. It significantly improves the capability of small arms used in close quarter fighting in all weathers. 展开更多
关键词 全息视觉 高斯点 全息图 轻武器 激光二极管
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Research on Airborne Electro-Optical Tracking and Sighting System Based on Fuzzy PID and H_∞ Control
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作者 刘珊中 孙隆和 车宏 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第4期286-291,共6页
Airborne electro-optical tracking and sighting system is a three-degree-of-freedom angular position servo system which is influenced by multi-disturbance,and its control system consists of stabilizing and tracking com... Airborne electro-optical tracking and sighting system is a three-degree-of-freedom angular position servo system which is influenced by multi-disturbance,and its control system consists of stabilizing and tracking components.Stabilizing control is applied to track angular velocity order and control multi-disturbance under airborne condition,and its robustness should be very good;tracking control is applied to compensate tracking error of angular position.A mathematical model is established by taking the control of yaw loop as example.H∞ stabilizing controller is designed by taking the advantage of H∞ control robustness and combining with Kalman filter.A fuzzy control is introduced in general PID control to design a decoupled fuzzy Smith estimating PID controller for tracking control.Simulation research shows that the control effect of airborne electro-optical tracking and sighting system based on fuzzy PID and H∞ control is good,especially when the model parameters change and the multi-disturbance exists,the system capability has little fall,but this system still can effectively track a target. 展开更多
关键词 控制导航技术 光电跟踪 视觉系统 稳定性 模糊控制
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光电系统中的自归零复合轴稳瞄系统
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作者 刘小强 牛帅旭 +5 位作者 杨修林 王虎 杨永安 张蕙菁 柳井莉 赵子淳 《兵工学报》 北大核心 2025年第1期346-353,共8页
针对传统复合轴稳瞄系统子轴运动范围较小、易积分饱和导致系统失效的问题,提出自归零复合轴稳瞄系统。在剖析传统复合轴稳瞄系统子轴易积分饱和致系统失效原由的基础上,提出主轴据强度函数随动子轴的自归零复合轴稳瞄系统,通过直观展... 针对传统复合轴稳瞄系统子轴运动范围较小、易积分饱和导致系统失效的问题,提出自归零复合轴稳瞄系统。在剖析传统复合轴稳瞄系统子轴易积分饱和致系统失效原由的基础上,提出主轴据强度函数随动子轴的自归零复合轴稳瞄系统,通过直观展示、理论分析及数学仿真软件仿真其在避免子轴积分饱和及增强系统抗扰特性方面的可行性及优势,并搭建试验平台开展试验验证。测试结果表明,在低频段,自归零复合轴稳瞄系统可在保证子轴扰动抑制能力的同时,大幅度增强系统的主轴扰动抑制能力,使主轴误差维持在较小值,避免子轴限位饱和。由此表明自归零复合轴稳瞄系统的可行性,及其在避免子轴限位饱和、维持系统稳定性方面的优势。 展开更多
关键词 光电系统 稳瞄系统 复合轴 自归零 快速反射镜
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城市环境下智能反射面辅助雷达非视距检测
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作者 杨鹏 周宇 +2 位作者 张宇佳 张哲昊 张世哲 《西安电子科技大学学报》 北大核心 2025年第1期130-141,共12页
雷达非视距目标探测是城市环境下的一个重要问题,建筑物等障碍在雷达与目标之间形成遮挡导致雷达检测性能受限,传统方法是利用电磁波在墙体等介质表面的反射来实现对盲区内目标的有效探测,然而电磁波在墙体处和传播过程中的衰减限制了... 雷达非视距目标探测是城市环境下的一个重要问题,建筑物等障碍在雷达与目标之间形成遮挡导致雷达检测性能受限,传统方法是利用电磁波在墙体等介质表面的反射来实现对盲区内目标的有效探测,然而电磁波在墙体处和传播过程中的衰减限制了探测范围。可重构智能表面是一种在空域能够将电磁波反射并实现能量聚焦的平面阵列,由低功耗的电子电路控制,通过调控元件反射系数可将信号聚焦于不同位置,智能反射面凭借其低成本、易部署、低功耗的优势能够广泛应用于城市环境中。受到智能反射面调控信号能力的启发,提出利用智能反射面辅助雷达非视距探测的方法,将信号转发至目标处从而绕过遮挡,并采用交替优化算法求解反射系数,旨在提高雷达在非视距场景下的目标检测性能,拓宽雷达在城市环境下的应用。仿真实验结果表明,相比传统方法智能反射面辅助雷达非视距目标探测范围得到提升,并且智能反射面增加元件数,位置布置靠近雷达端或目标处时检测性能能够得到增强。 展开更多
关键词 非视距 目标探测 可重构智能表面 交替优化
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近场毫米波雷达非视距全息成像算法
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作者 蒋留兵 黄乾超 车俐 《火力与指挥控制》 北大核心 2025年第1期33-40,共8页
非视距雷达成像技术旨在重建障碍物干扰下的隐藏目标,在自动驾驶、区域安防等领域具有极大的应用潜力。基于多输入多输出毫米波雷达,提出一种利用多径反射信号反演雷达视线外隐藏目标散射特性的二维成像技术。该方案采用高精度导轨搭载M... 非视距雷达成像技术旨在重建障碍物干扰下的隐藏目标,在自动驾驶、区域安防等领域具有极大的应用潜力。基于多输入多输出毫米波雷达,提出一种利用多径反射信号反演雷达视线外隐藏目标散射特性的二维成像技术。该方案采用高精度导轨搭载MIMO毫米波雷达扫描合成2-D等效均匀阵列,利用多径反射回波重构隐藏目标图像。此外,建立NLOS成像模型并提出一种基于2-D波数域算法和镜面对称的高精度成像方法。在该方法中通过对隐藏目标的横断面成像提取NLOS目标以及反射墙面的先验知识,利用先验知识结合镜面对称原理,实现NLOS目标冠状面高精度聚焦获得目标轮廓。通过NLOS毫米波成像系统验证了所提算法的有效性。 展开更多
关键词 非视距成像 毫米波雷达 波数域成像 合成孔径
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