用MSC.ADAMS对空间调制系统进行动力学分析

空间红外遥感仪器多采用双轴承高速转动结构,仪器的失效往往是由于转动部件轴承的失效而引起.本文以调制系统为例,在MSC.ADAMS软件环境下建立其动力学仿真模型.通过多次仿真,模拟出了轴向载荷以及径向载荷与轴承接触应力之间的关系.分析结果对于红外遥感仪器转动部件的设计具有指导意义.     

基于遥感反演的空间下视系统红外场景仿真

空间红外下视系统的真实感红外场景仿真一直以来都是研究的一个难点。提出了一种基于卫星红外遥感反演数据的空间下视红外场景仿真方法。利用红外遥感反演数据,通过匹配算法获得仿真波段内地表红外纹理,建立了下视红外观测模型,对地表红外纹理图像在传感器焦平面上重采样,最后按照辐射传输理论,计算生成光学入瞳前红外场景。仿真结果表明:该方法可以逼真地模拟地物场景红外纹理特征。将热红外遥感反演技术应用于红外场景仿真,极大简化了大规模地表场景仿真过程,为空间下视系统红外场景仿真提供了一种直观、有效的新方法。     

基于DMD的动态红外投影系统分光系统设计

动态红外投影技术是红外硬件闭环仿真(HWIL)和红外成像测试与评估的关键技术,它能够在实验室内实物模拟红外成像,从而降低光电系统的研发成本和提供可重复的实验环境。介绍了动态红外场景投影技术及其分类,描述了基于DMD动态红外场景分光系统的设计过程。为了解决系统中分光的问题,采用棱镜设计的理论设计了分光棱镜,给出了设计结果,经验证满足要求。为了获得更好的透过率和更紧密的结构,可以选取更好的材料来改进设计。     

一种光学载荷在轨杂散光效应全链路自动仿真方法

针对极轨气象卫星FY-3C载荷可见光扫描辐射计（VIRR）在轨红外定标时存在温度反演不一致的现象展开分析，提出了一种全链路自动化仿真分析方法，将仪器结构与卫星轨道参数和卫星平台环境相结合，通过对光机模型的高精度光线追迹来得到杂散光影响的定量化结果。仿真模拟了在轨红外定标和太阳光入射两种情况，确定了太阳杂散光的入射路径，解释了温度反演不一致的原因。将仿真结果与卫星在轨数据进行比对，验证了仿真方法的有效性。该方法可用于同类型载荷的在轨杂散光分析仿真工作，同时也为历史数据的再定标修正提供参考。     

基于Wishbone-PCI核的红外探测器注入式仿真系统

介绍了一种基于Wishbone-PCI桥核和Spartan6系列FPGA的红外探测器注入式仿真系统。重点讨论了基于PCI总线的红外图像注入接口卡的设计与实现以及Wishbone-PCI桥核技术。该系统可以代替红外侦察告警设备的头部探测器将红外仿真图像数据注入到红外告警、红外搜索跟踪等设备的实时信息处理箱,用来实现对红外侦察告警设备目标探测与目标跟踪功能的验证与仿真。该注入式仿真系统通过将前期红外侦察告警设备采集的红外图像数据与自定义的目标图像相叠加,注入到实时信息处理箱,因此该注入式仿真系统具有图像数据真实连续的特点,能更加真实地模拟现实的场景,为实时信号处理箱提供真实可靠的数据来源,有利于加快红外侦察告警设备的研发进程,缩短系统开发周期。     

基于Wishbone-PCI核的红外探测器注入式仿真系统

介绍了一种基于Wishbone-PCI桥核和Spartan-6系列FPGA的红外探测器注入式仿真系统.重点讨论了基于PCI总线的红外图像注入接口卡的设计与实现以及Wishbone-PCI桥核技术.该系统可以代替红外侦察告警设备的头部探测器将红外仿真图像数据注入到红外告警、红外搜索跟踪等设备的实时信息处理箱,用来实现对红外侦察告警设备目标探测与目标跟踪功能的验证与仿真.该注入式仿真系统通过将前期红外侦察告警设备采集的红外图像数据与自定义的目标图像相叠加,注入到实时信息处理箱,因此该注入式仿真系统具有图像数据真实连续的特点,能更加真实地模拟现实的场景,为实时信号处理箱提供真实可靠的数据来源,有利于加快红外侦察告警设备的研发进程,缩短系统开发周期.     

基于LabVIEW的红外场景生成器空间分辨率测试

红外场景生成器是在实验室条件下模拟目标和背景的红外辐射特性,为被测试的红外成像系统提供红外目标和背景的图像源设备。为了测试红外场景生成器的性能,设计了一种系统来测试场景生成器的空间分辨率。该系统通过计算系统输出矩形光栅图像的对比传递函数即可得到场景生成器系统的调制传递函数,从而得到系统的空间分辨率。     

基于半实物仿真的红外侦察告警系统性能评估方法

介绍了用于红外侦察告警系统性能评估的半实物仿真系统的硬件结构和软件模块组成。在仿真理论和野外测试数据的基础上,探讨了实验室半实物仿真系统测试的基本方法和建立目标及背景的红外模型的基本途径。通过实验室半实物仿真的方法模拟产生各种各类背景、干扰条件下各种目标几何尺寸、红外辐射、运动轨迹以及多目标的红外模拟目标。最后给出红外侦察告警系统的综合性能考核几个关键技术的分析。     

光电成像跟踪系统的仿真与评估技术研究

以光电成像跟踪系统的实验室检测和性能评估为研究方向,即在实验室环境下,模拟各种可见光和红外场景,评估在特定环境下光电成像跟踪系统的技术指标和性能是否符合要求。文中探讨了实验室仿真设备和计算机仿真软件的基本组成和功能,重点分析了虚拟仿真图像生成模块和图像算法仿真模块,文章最后给出了评估光电成像跟踪系统性能的实例。     

基于Visual C++和OpenGL的红外目标景象仿真研究

对红外目标的红外辐射特性进行了分析计算,提出了在Visual C++6.0环境下利用OpenGLAPI对空间目标红外辐射特性进行仿真的方法.针对假定目标给出了该目标在不同观察方向上的辐射强度并据此生成灰度图像,并利用上海技术物理研究所自行研制的128×128像素电阻阵列红外景象转换器进行了仿真实验,取得了实验结果.对红外目标的红外辐射特性仿真进行研究,为红外景象模拟提供基础.     

金星表面THz遥感探测

从“金星快车可见光与红外热成像光谱仪（VIRTIS）载荷成功地实现了对金星表面辐射探测”事实出发,利用高分辨率传输分子光谱数据库（HITRAN）,仿真验证了金星大气模型相适应的近红外大气窗口,从而分析并获取了金星 THz 大气窗口。与此相适应,从实现金星地表全天候遥感探测科学目标出发,系统阐述了金星大气 THz窗口下探测的优势,提出多功能金星遥感构想。     

Radiometer for the Pioneer Venus Orbiter

A review of the design and operation of a radiometer to study the upper atmosphere of Venus from the Pioneer Venus orbiter is presented.     

基于多点接地的载荷舱电磁辐射抑制技术研究

分别采用一种"多层快速多极子+多导体传输线理论"混合方法和实验方法,研究了多点接地技术对降低载荷舱内电缆电磁辐射的作用.首先,利用多导体传输线（multi-conductor transmission line,MTL）方法快速求解电缆区域泄漏电流;其次,将泄漏电流作为激励源,分谐振与非谐振两种状态,利用多层快速多极子方法准确、有效地对不同接地点数情况下载荷舱内电缆的电磁辐射进行仿真.实验结果和仿真结果证明了该混合方法的计算精度和高效性.最终得出结论:通过多点接地方式可以明显降低载荷舱内电缆非谐振状态下的电磁辐射,大大改善舱内复杂电磁环境,为航天电磁兼容工程设计提供理论指导.     

The Pioneer Venus Orbiter Plasma Analyzer Experiment

The plasma analyzer experiment on the Pioneer Venus Orbiter was designed to determine the basic characteristics of the plasma environment of Venus and the nature of the solar wind interaction at Venus. The plasma analyzer experiment is an electrostatic energy-per-unit charge (E/Q) spectrometer which measures ions and electrons. There is a curved plate electrostatic analyzer system with multiple collectors. The experiment obtains the three dimensional plasma distribution function. Some of the scientific objectives of the instrument are briefly discussed, the general characteristics of the experiment are summarized, and some of the analyses based on the data are presented.     

Pioneer Venus Spacecraft Design And Operation

The Pioneer Venus Orbiter and Multiprobe spacecraft design and operation enabled both remote and in-situ measurements of the Venusian environment from the outermost fringes of the atmosphere all the way to the surface. Both spacecraft were spin-stabilized and solar-cell powered from launch to Venus. Since orbit insertion, the Orbiter has been transmitting measurements from a highly elliptical 24-h orbit with periapsis altitudes down to about 150 km. Data rates up to 2048 bits/s have been utilized through a despun high-gain antenna transmitting at S-band frequency. Spacecraft attitudes, orbit periods, and periapsis altitudes are being maintained as required with a hydrazine propulsion system. The Multiprobe spacecraft (Bus with all four Probes attached) perfomed the necessary Probe checkouts and deployed the Probes to achieve the desired Probe and Bus targeting. Silver-zinc batteries provided the necessary power on each of the four Probes from separation from the Bus through the entry/descent sequence. Data rates of 256 and 128 bits/s on the Large Probe were maintained with 40-W radiated power, and 64 and 16 bits/s on the Small Probes were maintained with 10-W radiated power, through omni antennas directly to Earth-based stations. Each Probe's entry/descent sequence was controlled with a hardwired entry sequence programmer to achieve the desired scientific and spacecraft operations.     

Pioneer Venus Sounder Probe Gas Chromatograph

The Pioneer Venus Sounder Probe gas chromatograph (GC) instrument's design logic, construction, function, and data processing are discussed.     

High-gain backup antenna design for Pioneer Venus Orbiter spacecraft

The development and performance is described of a high-gain antenna designed to serve on the Pioneer Venus Orbiter spacecraft as a backup to the principal high-gain antenna unit in the unlikely event the mechanically despun antenna mechanism malfunctioned. The final design, a center-fed standing wave array of six sleeve dipoles enclosed in a fiber glass radome, performed successfully, as did all the antennas, on the Pioneer Orbiter spacecraft which was launched on May 20, 1978, as part of the Pioneer Venus mission. Photographs of experimental models giving details of design and construction are included, as well as graphs showing measured pattern and impedance matching characteristics of the subject antenna.     

Pioneer Venus Orbiter Neutral Gas Mass Spectrometer Experiment

The Pioneer Venus Orbiter Neutral Mass Spectrometer (ONMS) is designed to measure the vertical and horizontal density variations of the major neutral constituents in the upper atmosphere of Venus. The mass spectrometer sensor includes a retarding potential ion source, hyperbolic quadrupole rod analyzer, and electron multiplier detector. The supporting electronic system consists of hybrid integrated circuits to reduce weight and power. The ONMS instrument was launched aboard the Pioneer Venus Orbiter on May 20, 1978, and turned on in orbit around Venus on December 4, 1978. It has operated flawlessly for over a Venus year (243 earth days) and has returned data of the composition of the major constituents in the Venus atmosphere between the altitudes of 150 and 350 km.     

Pioneer Venus Occultation Radio Science Data Generation

Previous to the Pioneer Venus Orbiter mission, occultation radio science data were generated at the Deep Space Stations of NASA's Deep Space Network via the analog recording of the baseband frequency output signal of a relatively wide bandwidth open-loop receiver. Signal digitization was a separate and subsequent operation at the Jet Propulsion Laboratory. During Pioneer Venus Orbiter radio science operations, the open-loop receiver baseband frequency output signal bandwidth was substantially reduced. This was made possible by programming the open-loop receiver first local oscillator with the predicted Doppler frequency profile. In addition, the receiver output signal was digitized and recorded directly on computer compatible magnetic tape in real time. Initial results obtained with this new process, referred to as ?real-time bandwidth reduction,? during the prime Pioneer Venus Orbiter mission, compare very favorably to results obtained with the previous occultation system.     

Pioneer Venus Multiprobe Entry Telemetry Recovery

The Entry Phase of the Pioneer Venus Multiprobe Mission involved data transmission over only a two-hour span. The criticality of recovery of those two hours of data, coupled with the fact that there were no radio signals from the Probes until their arrival at Venus, dictated unique telemetry recovery approaches on the ground. The result was double redundancy, use of spectrum analyzers to aid in rapid acquisition of the signals, and development of a technique for recovery of telemetry data without the use of real-time coherent detection which is normally employed by all other NASA planetary missions.