期刊文献+
共找到3,934篇文章
< 1 2 197 >
每页显示 20 50 100
基于相位差变化率的无源定位及误差分析 预览
1
作者 姜智强 山世浩 +1 位作者 张恒 黄烽 《现代防御技术》 2020年第1期57-61,112,共6页
在分析基于相位差变化率二维无源定位原理和方法的基础上,建立了测向误差和测距误差模型。通过分析误差模型发现,相位差变化率误差是影响定位误差的主要因素。采用数字仿真的方式,分析了目标与观测站相对位置、相位差误差对测向误差的影... 在分析基于相位差变化率二维无源定位原理和方法的基础上,建立了测向误差和测距误差模型。通过分析误差模型发现,相位差变化率误差是影响定位误差的主要因素。采用数字仿真的方式,分析了目标与观测站相对位置、相位差误差对测向误差的影响,以及测向误差、相位差变化率误差对相对测距误差的影响。最后采用扩展卡尔曼滤波的方法对测距数据进行处理,实现了相对测距误差的快速收敛,进而有效提高了运动观测站对固定目标的无源定位精度。 展开更多
关键词 无源定位 相位差变化率 测向误差 测距误差 干涉仪 扩展卡尔曼滤波
在线阅读 下载PDF
匹配型迈克尔逊干涉结构中PZT相位调制对PGC解调算法的影响
2
作者 王夏霄 刘旭 +2 位作者 于佳 王婷婷 马福 《激光杂志》 北大核心 2020年第3期17-20,共4页
通过对相位生成载波(PGC)解调算法的仿真以及参考大量相关文献,可以发现调制度C对PGC解调结果有着极其重要的影响。而调制度C的大小由压电陶瓷PZT(Piezoelectric Transducter)对光路实际产生的相位调制决定,因此,对PZT光相位调制器相位... 通过对相位生成载波(PGC)解调算法的仿真以及参考大量相关文献,可以发现调制度C对PGC解调结果有着极其重要的影响。而调制度C的大小由压电陶瓷PZT(Piezoelectric Transducter)对光路实际产生的相位调制决定,因此,对PZT光相位调制器相位调制常数的校准以及实际产生的相位调制计算很重要。其中对于光相位调制器相位调制常数的校准,可以根据PZT的特性,对PZT施加固定频率的三角波电压,观察干涉信号的变化。通过分析匹配型迈克尔逊干涉仪的PZT调制方式,给出计算调制度C的公式,并分析了调制方式对载波调制度大小和相位的影响,得出PZT对光路信号调制两次,与PZT的调制度两次叠加基本相等,但是会对载波基频增加一个固定的相位延迟,对调制解调算算法有影响,需计算其具体大小,在运算时消掉其影响。 展开更多
关键词 干涉仪 相位生成载波 PGC解调 压电陶瓷 载波相位延迟
干涉型光纤水听器3×3反正切解调方法 预览
3
作者 代欣学 陈亚林 +1 位作者 贠晓辉 王海陆 《舰船科学技术》 北大核心 2020年第2期150-154,共5页
光纤水听器具有体积小、灵敏度高、传输损耗低、抗电磁干扰能力强等优点,这些优点极大地促进了其在海防领域的发展。为了实现耦合器相位特性不理想条件下的无失真解调,本文提出一种基于3×3光纤耦合器的反正切解调方法。首先推导出... 光纤水听器具有体积小、灵敏度高、传输损耗低、抗电磁干扰能力强等优点,这些优点极大地促进了其在海防领域的发展。为了实现耦合器相位特性不理想条件下的无失真解调,本文提出一种基于3×3光纤耦合器的反正切解调方法。首先推导出解调输出信号的表达式,给出解调频率范围。然后建立干涉型光纤水听器信号解调算法Simulink模型,并利用正切函数的性质,实现反正切相位扩展。在单频信号和线性调频信号条件下进行了仿真。仿真结果表明,该方法具有较宽的频率解调范围,消除了3×3耦合器的输出相位差对解调的影响。搭建基于此算法的干涉型光纤水听器解调系统,对实验数据进行了分析。结果证明了该方法的可行性和实用性,对干涉型光纤水听器的数字化解调系统设计具有一定的理论指导价值。 展开更多
关键词 水听器 干涉仪 零差解调
在线阅读 下载PDF
FDA发射干扰机对无源雷达干涉仪测向系统的欺骗机理 预览
4
作者 王博 谢军伟 +1 位作者 葛佳昂 张晶 《华南理工大学学报:自然科学版》 EI CAS CSCD 北大核心 2020年第1期93-103,共11页
针对雷达电子战中,敌方无源探测雷达通过接收干扰机信号实现测向定位,威胁我方干扰机安全的问题,提出一种基于频率分集阵列(Frequency Diverse Array,FDA)的测向交叉定位欺骗技术。首先在建立FDA阵列模型的基础上,通过欧拉公式得到采用... 针对雷达电子战中,敌方无源探测雷达通过接收干扰机信号实现测向定位,威胁我方干扰机安全的问题,提出一种基于频率分集阵列(Frequency Diverse Array,FDA)的测向交叉定位欺骗技术。首先在建立FDA阵列模型的基础上,通过欧拉公式得到采用非线性频控函数的FDA阵列因子及相位方向图;然后推导了FDA阵列作用于干涉仪测得的信号到达角β、虚拟发射机在X轴的坐标位置x;接着,以干涉仪测向欺骗为基础,分析了FDA干扰机对测向交叉定位系统的欺骗原理及定位精度。仿真结果表明:通过合理地对载频、阵元数目、频偏的选择可以较好地实现在远场条件下FDA阵列对干涉仪测向的欺骗效果;在合理选择其他参数的同时,测向精度越高、定位模糊区面积越小,且定位虚拟干扰机位置始终落在50%CEP半径之外。 展开更多
关键词 频率分集阵列 非线性频控函数 干涉仪 测向精度 角度欺骗 测向交叉定位
在线阅读 免费下载
运动单站单基线解模糊定位算法 预览
5
作者 郭立民 谢强 +1 位作者 陈涛 王梦馨 《中南大学学报:自然科学版》 EI CAS CSCD 北大核心 2019年第2期336-342,共7页
针对传统干涉仪多频段测向定位系统复杂、单基线测向模糊等问题,提出一种基于运动单站单基线对地面静止辐射源解模糊无源定位方法。首先,建立基于模糊相位差几何特性的无源定位模型,然后推导出在最大似然比条件下模糊相位差的代价函数,... 针对传统干涉仪多频段测向定位系统复杂、单基线测向模糊等问题,提出一种基于运动单站单基线对地面静止辐射源解模糊无源定位方法。首先,建立基于模糊相位差几何特性的无源定位模型,然后推导出在最大似然比条件下模糊相位差的代价函数,通过樽海鞘群优化算法估计辐射源位置,最后推导出该无源定位模型下的定位误差几何精度因子(GDOP)。研究结果表明:本文所提出的方法能够在低信噪比条件下达到较高的定位精度,仅利用单基线干涉仪即可对多个频段辐射源进行定位。 展开更多
关键词 无源定位 单站 干涉仪 相位差 樽海鞘群算法
在线阅读 下载PDF
Implementation of Full Spin-State Interferometer
6
作者 唐鹏举 彭鹏 +2 位作者 董翔宇 陈徐宗 周小计 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第5期7-11,共5页
Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in ea... Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in each run of the experiment, by the combination of the Majorana transition according to the exponential modulation of the magnetic field pulse decline curve and radio frequency coupling among multiple magnetic sub-states.Compared to the realization of two Majorana transitions, the interference fringe for the magnetic field insensitive state also has a higher contrast. After spatially overlapping the full magnetic sub-state interference patterns dozens of times in consecutive experimental measurements, clear fringes are still observed, indicating the great stability of the relative phases of different components. This indicates the potential to achieve an interferometer with multiple spin clocks. 展开更多
关键词 In IMPLEMENTATION of Full SPIN-STATE INTERFEROMETER
Complementarity via Minimum Error Measurement in a Two-Path Interferometer
7
作者 刘君昭 刘彦军 卢竞 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第5期12-16,共5页
We study the fringe visibility and the which-path information(WPI) of a general Mach-Zehnder interferometer with an asymmetric beam splitter(BS). A minimum error measurement in the detector is used to extract the WPI.... We study the fringe visibility and the which-path information(WPI) of a general Mach-Zehnder interferometer with an asymmetric beam splitter(BS). A minimum error measurement in the detector is used to extract the WPI. Both the fringe visibility V and the WPI Ipath are affected by the initial state of the photon and the second asymmetric BS. The condition in which the WPI takes the maximum is obtained. The complementarity relationship V2 + Ipath2 ≤ 1 is found, and the conditions for equality are also presented. 展开更多
关键词 WPI Complementarity VIA Minimum Error Measurement in a Two-Path INTERFEROMETER MZI
A Cosmic Microscope to Probe the Universe from Present to Cosmic Dawn:Dual-element Lowfrequency Space VLBI Observatory 预览
8
作者 AN Tao JAISWAL Sumit +2 位作者 MOHAN Prashanth ZHAO Zhen LAO Baoqiang 《空间科学学报》 CAS CSCD 北大核心 2019年第2期242-249,共8页
A space-based Very Long Baseline Interferometry (VLBI) program, named as the Cosmic Microscope, is proposed to involve dual VLBI telescopes in the space working together with giant ground-based telescopes (e.g., Squar... A space-based Very Long Baseline Interferometry (VLBI) program, named as the Cosmic Microscope, is proposed to involve dual VLBI telescopes in the space working together with giant ground-based telescopes (e.g., Square Kilometre Array, FAST, Arecibo) to image the low radio frequency Universe with the purpose of unraveling the compact structure of cosmic constituents including supermassive black holes and binaries, pulsars, astronomical masers and the underlying source, and exoplanets amongst others. The operational frequency bands are 30, 74, 330 and 1670 MHz, supporting broad science areas. The mission plans to launch two 30-m-diameter radio telescopes into 2 000 km×90 000 km elliptical orbits. The two telescopes can work in flexibly diverse modes,(i) Space-ground VLBI. The maximum space-ground baseline length is about100 000 km;it provides a high-dynamic-range imaging capacity with unprecedented high resolutions at low frequencies (0.3 mas at 1.67 GHz and 20 mas at 30 MHz) enabling studies of exoplanets and supermassive black hole binaries (which emit nanoHz gravitational waves),(ii) Space-space single-baseline VLBI. This unique baseline enables the detection of flaring hydroxyl masers, and more precise position measurement of pulsars and radio transients at mas level.(iii) Single dish mode, where each telescope can be used to monitor transient bursts and rapidly trigger follow-up VLBI observations. The large space telescope will also contribute in measuring and constraining the total angular power spectrum from the Epoch of Reionization. In short, the Cosmic Microscope offers astronomers the opportunity to conduct novel, frontier science. 展开更多
关键词 Space VLBI RADIO interferometer Low-frequency RADIO ASTRONOMY Transient EXOPLANET
在线阅读 下载PDF
System Design for the Event Horizon Imaging Experiment Using the PECMEO Concept 预览
9
作者 KUDRIASHOV Volodymyr MARTIN-NEIRA Manuel +4 位作者 BARAT Itziar MARTIN IGLESIAS Pertonilo DAGANZO-EUSEBIO Elena ALAGHA Nader VALENTA Vaclav 《空间科学学报》 CAS CSCD 北大核心 2019年第2期250-266,共17页
The concept for space interferometry from Polar or Equatorial Circular Medium Earth Orbits(the PECMEO concept) is a promising way to acquire the image of the"shadow"of the event horizon of Sagittarius A*with... The concept for space interferometry from Polar or Equatorial Circular Medium Earth Orbits(the PECMEO concept) is a promising way to acquire the image of the"shadow"of the event horizon of Sagittarius A*with an angular resolution of circa 5 microarcseconds. The concept is intended to decrease the size of the main reflector of the instrument to about 3 m using a precise orbit reconstruction based on Global Navigation Satellite System (GNSS) navigation, inter-satellite range and range-rate measurements, and data from the Attitude and Orbit Determination System (AODS). The paper provides the current progress on the definition of the subsystems required for the concept on the basis of simulations, radio regulations, and available technology. The paper proposes the requirement for the localization of the phase centre of the main reflector. The paper provides information about the visibility of GNSS satellites and the needed accuracies of the AODS. The paper proposes the frequency plan for the instrument and its Inter-Satellite Links (ISLs).The concepts for measurement of range and range-rate using ISLs (as well as for the data exchange at these ISLs) are presented. The block diagram of the interferometer is described and its sensitivity is estimated. The link budget for both ISLs is given as well as their critical components. The calculated measurement quality factors are given. The paper shows the expected performance of the sub-systems of the interferometer. The requirements for the localization of the main reflectors and the information about the availability of the GNSS satellites are based on the simulations results. The frequency plan is obtained according to the PECMEO concept and taking into account the radio regulations. The existing technology defines the accuracies of the AODS, both the link budgets and the fundamental measurement accuracies for ISLs, and the sensitivity of the instrument. The paper provides input information for the development of the orbit reconstruction filter and the whole PECMEO system 展开更多
关键词 INSTRUMENTATION TELESCOPE High ANGULAR RESOLUTION INTERFEROMETER Space VLBI
在线阅读 下载PDF
Coulomb-dominated oscillations in a graphene quantum Hall Fabry–Pérot interferometer
10
作者 张冠群 林立 +3 位作者 彭海琳 刘忠范 康宁 徐洪起 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第12期43-47,共5页
The electronic Fabry–Pérot interferometer operating in the quantum Hall regime may be a promising tool for probing edge state interferences and studying the non-Abelian statistics of fractionally charged quasipa... The electronic Fabry–Pérot interferometer operating in the quantum Hall regime may be a promising tool for probing edge state interferences and studying the non-Abelian statistics of fractionally charged quasiparticles. Here we report on realizing a quantum Hall Fabry–Pérot interferometer based on monolayer graphene. We observe resistance oscillations as a function of perpendicular magnetic field and gate voltage both on the electron and hole sides. Their Coulomb-dominated origin is revealed by the positive(negative) slope of the constant phase lines in the plane of magnetic field and gate voltage on the electron(hole) side. Our work demonstrates that the graphene interferometer is feasible and paves the way for the studies of edge state interferences since high-Landau-level and even denominator fractional quantum Hall states have been found in graphene. 展开更多
关键词 GRAPHENE electronic Fabry–Pérot INTERFEROMETER quantum Hall effect edge state interference
一种高精度宽带干涉仪相位校准方法 预览
11
作者 先登飞 《数字技术与应用》 2019年第3期210-212,共3页
为了提高宽带干涉仪测向系统的测向精度,提出了一种动静结合的干涉仪通道相位校准方法。将干涉仪测向系统划分为校准电路单元和测向电路单元,采用事先对校准电路单元相位参数静态测量获取各通道准确的相位参数表,再结合该参数表完成测... 为了提高宽带干涉仪测向系统的测向精度,提出了一种动静结合的干涉仪通道相位校准方法。将干涉仪测向系统划分为校准电路单元和测向电路单元,采用事先对校准电路单元相位参数静态测量获取各通道准确的相位参数表,再结合该参数表完成测向电路单元中多路接收通道动态校准。通过样机测试验证,相对传统校准方法,该方法校准精度高,提升了系统测向精度,能随系统进行在线动态校准,在干涉仪测向、相控阵雷达收发通道相位校准方面具有很好的推广意义。 展开更多
关键词 干涉仪 测向 校准 高精度 多通道 宽带
在线阅读 下载PDF
频率分集阵列对干涉仪的角度欺骗效果
12
作者 葛佳昂 谢军伟 +2 位作者 张浩为 冯晓宇 张晶 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2019年第1期183-191,共9页
针对干涉仪的测向隐蔽性问题,提出了一种基于频率分集阵列(FDA)对干涉仪的角度欺骗方法。干涉仪通过求取各天线接收到信号的相位差确定信号到达角,而FDA由于各阵元具有微小频偏造成其相位差并不满足求解关系,从而实现角度欺骗。首先,利... 针对干涉仪的测向隐蔽性问题,提出了一种基于频率分集阵列(FDA)对干涉仪的角度欺骗方法。干涉仪通过求取各天线接收到信号的相位差确定信号到达角,而FDA由于各阵元具有微小频偏造成其相位差并不满足求解关系,从而实现角度欺骗。首先,利用模型建立法和欧拉公式法2种方法建立了FDA波束相位模型;然后,从建立的2种模型出发,论证了FDA发出信号对干涉仪具有角度欺骗效果;最后,仿真分析了干扰距离、阵元间距、发射频率、频率增量等因素的影响。理论分析与仿真结果表明,FDA对处于远场的干涉仪目标有良好的欺骗效果。 展开更多
关键词 频率分集阵列(FDA) 角度欺骗 干涉仪 欧拉公式 相位差
Nanoliter liquid refractive index sensing using a silica V-groove fiber interferometer
13
作者 Quan Chai Hyeonwoo Lee +4 位作者 Seongjin Hong Yongsoo Lee Junbum Park Jianzhong Zhang Kyunghwan Oh 《光子学研究:英文版》 CSCD 2019年第7期107-112,共6页
A unique all-fiber interferometric sensor was proposed and successfully demonstrated efficient low-refractiveindex liquid sensing in the range from 1.33 to 1.37, which is compatible with those of bio-liquids.A special... A unique all-fiber interferometric sensor was proposed and successfully demonstrated efficient low-refractiveindex liquid sensing in the range from 1.33 to 1.37, which is compatible with those of bio-liquids.A special silica coreless optical fiber with an open V-groove was used as an optical sensing medium, which provided a high sensitivity for a minute liquid volume in the nanoliter scale.The V-groove fiber (VGF) was serially concatenated between two single-mode fibers (SMFs).The LPOi mode guided along the input SMF excited the higherorder inodes in the VGF to generate multimode interference,whose spectrum was transmitted through the output SMF. A single liquid droplet with volume of ~80 nanoliters wet the entire hydrophilic surface of the VGF, and the transmission spectra shifted corresponding to its refractive index in a very linear manner. The sensor also showed a negligible temperature cross-sensitivity in the range 25℃-75℃, which overlaps with the biological temperature window such that the sensitivity of 159.696 nm per refractive index unit(nm/RIU) remained independent of the temperature variation. Modal properties of VGF were thoroughly analyzed numerically, and detailed processes for the sensor fabrication and sensing experiments were reported. 展开更多
关键词 INTERFEROMETER PROCESSES FABRICATION
等厚等倾复合型干涉仪 预览
14
作者 梁辉 李岩 +1 位作者 付跃刚 林鹤 《长春理工大学学报:自然科学版》 2019年第1期13-17,共5页
干涉仪是可以快速高效,非接触地获取被测元件信息的光学测量仪器。为拓展单个干涉仪应用范围,设计出一种利用切换式系统,能根据测量需求实现等厚干涉和等倾干涉之间转换的复合型干涉仪。在介绍复合型干涉仪基本结构的基础上,分析了干涉... 干涉仪是可以快速高效,非接触地获取被测元件信息的光学测量仪器。为拓展单个干涉仪应用范围,设计出一种利用切换式系统,能根据测量需求实现等厚干涉和等倾干涉之间转换的复合型干涉仪。在介绍复合型干涉仪基本结构的基础上,分析了干涉仪设计中需要注意的问题和事项,着重讨论了光源的选择,准直物镜像差要求,聚光镜设计参数。利用ZEMAX软件完成了干涉仪光学系统的设计。最后,用FRED软件对干涉仪建模,进行仿真分析,得到了等厚干涉和等倾干涉干涉图,干涉条纹均清晰可见。表明此干涉仪可应用于实际光学测量之中。 展开更多
关键词 干涉仪 光学测量 切换式系统 光学设计 仿真
在线阅读 下载PDF
Application of MZI Symmetrical Structure With Fiber Balls and Seven-Core Fiber in Microdisplacement Measurement
15
作者 Hong LI Yanming SONG +1 位作者 Mingli DONG Lianqing ZHU 《光子传感器:英文版》 EI CAS CSCD 2019年第2期97-107,共11页
An optical fiber microdisplacement sensor based on symmetric Mach-Zehnder interferometer (MZI) with a seven-core fiber and two single-mode fiber balls is proposed. The rationality and manufacturing process of the MZI ... An optical fiber microdisplacement sensor based on symmetric Mach-Zehnder interferometer (MZI) with a seven-core fiber and two single-mode fiber balls is proposed. The rationality and manufacturing process of the MZI sensing structure are analyzed. The fabrication mechanism of the Mach-Zehnder sensor by CO2 laser is described in detail. Experimental results show that temperature sensitivities of the two dips are 98.65 pm/℃ and 89.72pm/℃, respectively. The microdisplacement sensitivities are 2017.71 pm/mm and 2457.92 pm/mm, respectively. The simultaneous measurement of temperature and microdisplacement is demonstrated based on the sensitive matrix. The proposed Mach-Zehnder interference sensor exhibits the advantages of compact structure, simple manufacturing process, and high reliability. 展开更多
关键词 Microdisplacement Mach-Zehnder interferometer FIBER ball SYMMETRICAL STRUCTURE seven-core FIBER
High Sensitive Refractive Index Sensor Based on Cladding Etched Photonic Crystal Fiber Mach-Zehnder Interferometer
16
作者 Haifeng DU Xiaoyan SUN +2 位作者 Youwang HU Xinran DONG Jianhang ZHOU 《光子传感器:英文版》 EI CAS CSCD 2019年第2期126-134,共9页
A high sensitive refractive index sensor based on the cladding etched photonic crystal fiber (PCF) Mach-Zehnder interferometer (MZI) is proposed, which is spliced a section of photonic crystal fiber between two single... A high sensitive refractive index sensor based on the cladding etched photonic crystal fiber (PCF) Mach-Zehnder interferometer (MZI) is proposed, which is spliced a section of photonic crystal fiber between two single modes fibers (SMFs).The interference fringe of the MZI shifts with the variation of the ambient refractive index (RI). It is found that the RI sensitivity slightly decrease with an increase in the interference length. The sensitivities of MZI with 35inm PCF, 40mm PCF, and 45mm PCF are 106.19nm/RIU, 93.33nm/RIU, and 73.64nm/RIU, respectively, in the range of 13.33 to 1.381. After etched, the RI sensitivity of the MZI could be improved obviously. The RI sensitivities of the MZI with 35 mm PCF are up to 211.53nm/RIU and 359.37nm/RIU when the cladding diameter decreases to 112(im and 91 pm, respectively. Moreover, the sensor is insensitive to temperature, and the measured sensitivity is only 9.21 pm/℃ with the range from 20℃ to 500℃. In addition, the sensor has advantage of simple fabrication, low cost, and high RI sensitivity. 展开更多
关键词 Refractive index sensor MACH-ZEHNDER INTERFEROMETER PHOTONIC crystal fiber hydrofluoric acid
Fiber in-line magnetic field sensor based on Mach-Zehnder interferometer integrated with magnetic fluid
17
作者 雷雪琴 徐彦超 +1 位作者 于雅婷 彭保进 《光电子快报:英文版》 EI 2019年第1期43-47,共5页
In this paper, magnetic fluid(MF), a new type of optical functional nanomaterial with interesting optical characteristics under the external magnetic field, is adopted to form a novel fiber-optic magnetic field sensor... In this paper, magnetic fluid(MF), a new type of optical functional nanomaterial with interesting optical characteristics under the external magnetic field, is adopted to form a novel fiber-optic magnetic field sensor. The proposed sensor is based on Mach-Zehnder interferometer (MZI) and has a multimode-singlemode-multimode(MSM) fiber structure. The MSM structure was fabricated by splicing a section of uncoated single mode fiber (SMF) between two short sections of multimode fibers(MMFs) using a fiber fusion splicer. The magnetic field sensing probe was made by inserting the fiberoptic structure in an MF-filled capillary tube. Variations in an external magnetic field is seen to cause changes in the refractive index of MF. This tunable change in the refractive index with magnetic field strengths between 0.6 mT to 21.4 mT produces a shift in the peak position of the wavelength. The shift of the valley wavelength with magnetic field intensity has a good linearity of up to 99.6%. The achieved sensitivity of the proposed magnetic field sensor is 0.123 nm/mT, which is improved by several folds compared with those of most of the other reported MF-based magnetic field sensors. Furthermore, we build the corresponding circuit-based measurement system, and the experimental results show that the voltage change indirectly reflects the change of the external magnetic field strength. Therefore, this provides the potential to fiber-based magnetic field sensing applications. 展开更多
关键词 field SENSOR INTERFEROMETER characteristics
Negativity of Wigner function and phase sensitivity of an SU(1,1) interferometer
18
作者 刘春丽 郭丽丽 +1 位作者 张智明 於亚飞 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期121-125,共5页
Both the negativity of Wigner function and the phase sensitivity of an SU(1,1) interferometer are investigated in this paper. In the case that the even coherent state and squeezed vacuum state are input into the inter... Both the negativity of Wigner function and the phase sensitivity of an SU(1,1) interferometer are investigated in this paper. In the case that the even coherent state and squeezed vacuum state are input into the interferometer, the Heisenberg limit can be approached with parity detection. At the same time, the negativity volume of Wigner function of detection mode comes entirely from the input state and varies periodically with the encoding phase. In addition, the negativity volume of Wigner function is positively correlated with the phase sensitivity of the SU(1,1) interferometer. The positive correlation may mean that the non-classicality indicated by negative Wigner function is a kind of resource that can verify some related research results of phase estimation. 展开更多
关键词 SU(1 1) INTERFEROMETER WIGNER FUNCTION PHASE sensitivity
Fringe visibility and distinguishability in two-path interferometer with an asymmetric beam splitter
19
作者 刘彦军 卢竞 +2 位作者 彭智慧 周兰 郑东宁 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第3期109-113,共5页
We study the fringe visibility and the distinguishability of a general Mach-Zehnder interferometer with an asymmetric beam splitter. Both the fringe visibility V and the distinguishability D are affected by the input ... We study the fringe visibility and the distinguishability of a general Mach-Zehnder interferometer with an asymmetric beam splitter. Both the fringe visibility V and the distinguishability D are affected by the input state of the particle characterized by the Bloch vector S =(S_x, S_y, S_z) and the second asymmetric beam splitter characterized by the paramterβ. For the total system is initially in a pure state, it is found that the fringe visibility reaches the upper bound and the distinguishability reaches the lower bound when cosβ=-S_x, The fringe visibility obtain the maximum only if S_x = 0 and β = π/2 when the input particle is initially in a mixed state. The complementary relationship V~2 +D~2 ≤ 1 is proved in a general Mach-Zehnder interferometer with an asymmetric beam splitter, and the conditions for the equality are also presented. 展开更多
关键词 complementarity FRINGE VISIBILITY DISTINGUISHABILITY general Mach–Zehnder INTERFEROMETER
FDA对测向时差组合定位的欺骗研究 预览
20
作者 王博 谢军伟 +1 位作者 葛佳昂 张晶 《空军工程大学学报:自然科学版》 CSCD 北大核心 2019年第6期72-78,共7页
针对雷达电子战中,敌方无源探测雷达通过接收干扰机信号实现测向定位,威胁我方干扰机安全的问题,提出一种基于频率分集阵列(FDA)的测向时差组合定位欺骗技术。首先在建立FDA阵列模型的基础上,通过欧拉公式得到采用非线性频控函数的FDA... 针对雷达电子战中,敌方无源探测雷达通过接收干扰机信号实现测向定位,威胁我方干扰机安全的问题,提出一种基于频率分集阵列(FDA)的测向时差组合定位欺骗技术。首先在建立FDA阵列模型的基础上,通过欧拉公式得到采用非线性频控函数的FDA阵列因子及相位方向图;之后推导了FDA阵列作用于干涉仪测得的信号到达角β;之后,以虚拟干扰机位置与真实位置的欧氏距离D为评价指标,分析欺骗效果。仿真结果表明,阵列载频位于L、S波段的欺骗效果优于X波段。在一定参数范围内,D值随着阵列阵元总数、阵列载频的增加而增大。远场条件下,采用正弦及对数频控函数的FDA阵列在消除方向图耦合的同时,其定位欺骗的D值取值在6~10 km之间。 展开更多
关键词 频率分集阵列 非线性频偏 干涉仪 欧拉公式 测向时差定位
在线阅读 免费下载
上一页 1 2 197 下一页 到第
使用帮助 返回顶部 意见反馈