一种飞行器电气系统综合测试平台设计

为解决传统飞行器电气系统综合测试中存在的测试设备种类繁多、测试项目覆盖性差等诸多问题,在某飞行器测试覆盖能力改进项目中,提出一种基于PXI总线架构的综合测试平台设计思路,通过模块化的硬件与软件架构设计,完成飞行器电气系统的综合测试平台设计,并结合实际测试需求进行具体开发,实践表明该系统能够保证飞行器现场测试有序、规范、安全。     

飞行器供配电系统地面通用测试接口设计

供配电地面测试负责为飞行器提供模拟供电、控制状态切换、采集并传输系统状态信息,配合完成全飞行器全周期的综合测试任务。本文首先简要介绍了供配电地面测试系统的基本功能和设备组成,然后对供电、控制、测量的接口设计进行分析,最后提出接口通用化设计方案。本文为电气系统地面通用化测试研究提供了有益尝试。     

航电设备通用检测维护台的设计

为了适应机载武器装备系统的多样化以及通用性要求,搭建了基于PXI总线的航电设备通用检测维护台,在系统架构、硬件设计以及软件开发等各方面进行了通用性设计。该航电设备通用检测维护台基于PXI构架,挂装不同种类的适配器,操作通用平台上的人机接口,可满足多种设备的检测、测试任务。航电设备通用检测维护台在一个机柜内实现了人机交互操作,大功率、高精度、多种类通用电源及PXI智能测试平台等的高度集成。该通用平台具有良好的通用性和扩展性,适用多种机型、多种航电设备。通用平台已在某型航电设备的检测维护中完成了工程验证,系统性能稳定,适用性强,可实现多种航电设备的检测维护工作,也可推广至海军舰艇、兵器车载装备等。     

基于PXI总线的导弹测试系统设计

为了满足某型导弹的批生产测试需求,设计了基于PXI总线的导弹测试系统。介绍了该测试系统的系统组成、工作原理,详细阐述了硬件系统和软件系统的设计方法和思路。经过实践证明,该测试系统可实现导弹的全时序自动化测试,工作稳定、可靠性高,能够很好的满足某型导弹的测试需求。     

飞行器供配电系统通用测试方案设计

供配电测试设备中专用设备比例仍较高,导致研制费用高,使用维护不便,操作人员需熟悉各种设备,人员培训也形成了困难;通过飞行器通用测试需求分析,结合某项目供配电测试系统方案,提出设备通用、软件可二次编程的设计方案;通用性测试方案减少了专用设备数量,降低研制费用,提高使用效率,有利于提高设备继承性和互换性,实现供配电测试系统高可靠设计;经过通用化设计,设备功能满足设计要求,指标显著提高,且满足后续项目需求;最后展望了飞行器测试系统的技术发展和应用前景。     

基于VeriStand的实时飞行测试系统设计与实现

针对飞行器改装带来的实时模飞测试问题,提出了一种实时飞行测试系统设计及实现方案。首先分析了待测飞控及安控系统的工作过程和技术特性,给出了实时测试系统应该具备的功能。基于功能需求,明确了系统采用PC上位机-PXI实时下位机的硬件架构,同时给出了上位机、下位机的硬件资源配置。系统采用VeriStand、MathWorks Simulink?、LabVIEW分别完成实时测试项目配置与管理、实时模型开发、虚拟串口设备驱动开发任务,并详细讨论了实时模型和虚拟串口设备驱动的开发过程。最后分析了实时测试结果。     

空空导弹测试系统应用LXI总线研究

首先对空空导弹测试系统应用各种仪器总线的情况进行了分析研究,然后介绍了一台PXI总线测试设备的改造方案,该方案中设计了一套基于LXI总线控制的电源子系统,该子系统与PXI主系统一起形成了新的混合总线控制测试设备。该改造方案实现了改造需求中的低成本和小型化设计。同时,结合该方案分析了LXI总线在空空导弹测试系统上应用的优缺点和现阶段局限性。提出了空空导弹测试系统应向着通用、开放和网络化方向发展的观点,得出了未来的空空导弹测试系统将是包含GPIB、VXI、PXI、LXI等总线接口的合成系统,各总线接口仅是网络上的一个节点的结论。     

航天器数字化测试模式设计与应用

随着航天事业的发展,航天器将迎来高密度的研制和发射任务。测试设计和实施同步、测试现场消耗大的测试模式导致测试效率低下,不能满足未来的综合测试需求。为解决航天器测试效率不能适应测试任务的问题,设计了航天器数字化测试模式。搭建数字化测试平台,实现测试准备、测试实施、测试评估全周期自动化。基于数字化测试平台,开展综合测试专业化设计与实施。推进测试设计与测试实施分离,将测试设计工作前移,测试设计人员通过测试用例与测试判据的精细化设计,将测试准备工作做充分,实现测试实施和评估过程自动化。数字化测试模式应用于多个航天器型号综合测试,形成多个固化测试用例数据库,有效提升测试效率,为后续型号测试能力的提升奠定坚实的基础。     

通用串行航空总线综合测试系统设计

针对目前串行航空总线测试设备功能单一的问题,设计了一种兼容多总线的便携式通用串行航空总线综合测试系统。方案采用模块化设计,详细叙述了系统的硬件及软件设计,系统由通用串行总线仿真设备终端与测试分析设备构成,系统涉及多种串行航空总线,可完成多总线仿真激励输出、监控接收及数据仿真分析功能,可最大程度满足航空电子系统的设备与系统仿真需求。实验结果表明,该通用串行航空总线综合测试系统稳定性好、可靠性高、使用便捷,满足设计需求。     

基于虚拟仪器的舵机综合测试系统设计

为了在实验室条件下模拟舵机系统实际飞行时所受的气动载荷,实现舵机部件和整机的动静态测试,设计了基于虚拟仪器的舵机综合测试系统。针对舵机测试系统自动化化和综合化需求,基于PXI架构和LabWindows/CVI平台,完成了测试系统的硬件设计和软件设计,采用异步定时器实现了实时数据采集,采用tdms数据流实现了大容量高速数据的记录,运用多线程实现了良好的人机交互与流畅的曲线显示,采用ActiveX技术调用Excel实现了测试报表的自动生成。使用和测试结果表明,该测试系统显著提高了舵机测试的效率和精确度以及自动化水平,使用方便,性能稳定,为舵机性能测试和设计优化提供了可靠保障。     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Hybrid Wavelength and Code Division Multiple Access in Optical Networks

A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Research on beamforming method for dual-line array with space mismatch between the two line arrays

The performance of port/starboard discrimination of dual-line array will be seriously degraded when the space between the two line arrays of the dual-line array is mismatched. The directivity function of the delay-sum and delay-subtract beamforming is deduced and the port/starboard discrimination of the delay-sum and delay-subtract beamforming is also studied both under the ideal status and the status under which the space between the two line arrays of the dual-line array is mismatched. Analysis results show the delay-subtract beamforming has better performance of port/starboard discrimination. At last, the sea trial results demonstrate the theoretical results.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Retrieval of ultraviolet skylight radiances and O3 slant column densities from balloon-borne limb spectrometer

With a novel light-weight and absolutely calibrated ultraviolet （UV） spectrometer, UV skylight radiances and O3 slant column densities are measured by balloon-borne limb measurements in Xinjiang area, China. UV skylight radiances measured at the height of 31 km are compared with the results from Modtran in the wavelength range from 290 to 420 nm. O3 slant column densities are derived from radiance spectra in the Huggins bands （320 - 335 nm） using differential optical absorption spectroscopy method. And the parameter exhibits a good correlation with the same value simulated by radiative transfer model （Tracy）. The O3 profile simultaneously measured by an O3 sonde is used as input in Tracy calculations. The O3 sonde is launched on the same balloon.     

Design optimization of highly sensitive LSPR enhanced surface plasmon resonance biosensors with nanoholes

For breaking through the sensitivity limitation of conventional surface plasmon resonance (SPR) biosensors, novel highly sensitive SPR biosensors with Au nanoparticles and nanogratings enhancement have been proposed recently.But in practice, these structures have obvious disadvantages.In this study, a nanohole based sensitivity enhancement SPR biosensor is proposed and the influence of different structural parameters on the performance is investigated by using rigorous coupled wave analysis (RCWA).Electromagnetic field distributions around the nanohole are also given out to directly explain the performance difference for various structural parameters.The results indicate that significant sensitivity increase is associated with localized surface plasmons (LSPs) excitation mediated by nanoholes.Except to outcome the weakness of other LSP based biosensors, larger resonance angle shift, reflectance amplitude, and sharper SPR curves' width are obtained simultaneously under optimized structural parameters.     

Polymer gratings based on photopolymerization for low-order distributed feedback polymer lasers

Novel polymer distributed feedback(DFB)gratings are fabricated based on photopolymerization to reduce lasing threshold of polymer lasers.A photopolymer formulation sensitive to 355-nm ultraviolet(UV)light is proposed for the fabrication of polymer gratings and it can be used to form polymer films by spin-coating process.A very low surface-relief depth ranging from 12.5 to about 1.0 nm has been demonstrated with a refractive-index modulation of about 0.012.The experimental results indicate that such polymer gratings have promising potentials for the fabrication of low-order DFB organic semiconductor lasers.