共查询到20条相似文献,搜索用时 15 毫秒
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深空探测对航天器热控技术的推动 总被引:1,自引:0,他引:1
工程热物理学广泛应用于航天领域,一方面解决了具体航天工程问题,另一方面逐步发展成为交叉学科——空间热物理。随着我国在深空探测领域不断拓展,以深空探测器研制中的工程热物理问题为需求背景,推动着航天器热控制技术、防热技术等取得新的发展。文章在介绍深空探测器技术体系的基础上,分析了热设计、热分析、热试验、热控硬件、防热等方面的技术进步,并就深空探测领域进一步拓展对工程热物理发展的牵引进行了展望,分析了工程热物理学与航天技术间相互促进、相互推动的关系。 相似文献
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Petr Lla 《Acta Astronautica》1996,39(9-12):647-655
The Committee on the Peaceful Uses of Outer Space (COPUOS) was established in 1959 by the United Nations General Assembly in order to review and foster international cooperation in the peaceful uses of outer space and to consider legal issues arising from the exploration of outer space. Since its establishment, the Committee has addressed such issues as benefits from space activities, the definition and delimitation of outer space and the use of the geostationary orbit, implications of remote sensing, space sciences, space-based communications, navigation and meteorological systems, as well as use of nuclear power sources in outer space, space debris and spin-off benefits of space technology. At its session in 1996, a symposium on the ‘Utilization of micro- and small satellites for the expansion of low-cost space activities, taking into particular account the needs of developing countries’ was organized by COSPAR and IAF to complement discussions on this theme. It was noted at the symposium that the increasing number of small satellites, in particular the proposed introduction of multi-satellite ‘constellations’ at low orbits, would result in concentrations of satellite mass at certain regions of space around the Earth. Special provisions would be needed to minimize the probability of satellite breakups and collisions which might create more space debris and compromise the future of spaceflight. 相似文献
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India in Asia and Brazil in Latin America are regarded as the most promising global economies. This paper examines the openings and possibilities for space technology collaboration between India and Latin American states under the larger rubric of science and technology collaboration. While the distance and language barriers between the two regions have proved a hindrance in the past, the paper proceeds with an assumption that, in the 21st century, such barriers should not be a limitation on developing strategic, economic, and science and technology partnerships among nation-states. The paper argues that the Latin American states are keen to have their own satellites because of their significant utility in the socioeconomic sector and this offers an opportunity to India to use cooperation in space technologies as a powerful tool for engagement in Latin America. 相似文献
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In 1994-1995 Lavochkin Association (Russia) together with the other enterprises in accordance with technical requirements of the Russian Space agency, developed a new Russian communication satellite of a small class that will operate in both the geostationary (GSO) and high-elliptical (HEO) orbits. This satellite may be injected into operational orbits using a SOYUZ-2 launch vehicle (LV) and a FREGAT upper stage (US) from Plesetsk and Baykonur space launch sites (SLS).The main reason for creating such a satellite was to decrease the cost of the support and development of the Russian communication geostationary satellites group.Russian satellites Horizont, Express, Ekran and Gals, which operate in GSO, are the basis of the space segment for communications, radio and TV broadcasting. All of these satellites are injected into GSO by the PROTON LV. PROTON is a launch vehicle of a heavy class. The use of a middle class LV instead of a heavy class will allow to reduce considerably the launch cost. The change of a heavy class LV to a LV of middle class determined one economic reason for this project. Besides, the opportunity to launch S/C into GSO from Russian Plesetsk SLS increases the independence of Russia in the domain of space communications, despite the presence of the contract with Kazachstan about the rent of Baykonur SLS. Finally, use of small satellites with a rather small number of transponders is more effective than the use of big satellites. It will allow also to increase a satellite group (by the launch of additional satellites) precisely in accordance to the development of the ground segment. 相似文献
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美国AEHF军事通信卫星推进系统及其在首发星上的应用 总被引:2,自引:0,他引:2
美国先进极高频(AEHF)项目将采用4颗运行于地球同步轨道(GEO)的AE—HF军事通信卫星。AEHF卫星的推进系统由远地点发动机、姿态控制发动机组和双模式霍尔电推进子系统组成。首发星AEHF-1是世界上首个采用霍尔电推进系统执行发射后轨道提升任夯的GEO卫星。AEHF-1卫星星箭分离后,远地点发动机未能正常工作,因此... 相似文献
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Osamu Takeda Yukio Hashimoto Yoichi Kawakami Shigetoshi Yoshimoto Hideki Katagiri 《Acta Astronautica》1999,44(7-12):365-373
This paper describes the research and development of an On-Board Processor (OBP) for a mobile satellite communications system using a geostationaly satellite. The system, which based on Multi-Carrier Time Division Multiple Access, can realize high performance and facilitate the use of miniature hand-held mobile Earth terminals.
Our research and development results indicate as follows.
- 1. 1) The simultaneous-slot switching method will be the most suitable for an on-board base-band switching with consideration of traffic capacity, time delay, and hardware scale.
- 2. 2) The OBP performs channel exchange with regeneration that contributes to a reduction in the size of mobile terminals because of the coding gain.
- 3. 3) Many kinds of Application Specific Integrated Circuits are designed to realize large channel capacity and reduce the size and power consumption of the OBP. These OBP design can increase the channel capacity, which is equivalent to in 5.6kbps voice channel, up to over 500 channels within 5MHz frequency band
Some results are applied to the OBP being developed for the Japanese Engineering Test Satellite VII (ETS-VB). 相似文献
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为适应低轨小卫星星座体系化应用需求,设计、实践出一套面向批产的小卫星研制模式。某批产小卫星星座通过整星仅一次合板即最终状态,产品交付即落焊,裁剪、简化环境试验,投产管路模板实现卫星结构装配与管路焊装并行实施,发射场带翼运输,全无线测试等批产创新策略,构建了小卫星批产体系,实现了年出厂20颗以上500 kg级小卫星的能力,为建设高密度小卫星星座奠定了基础。批产策略与方法均经实际验证,与传统小卫星研制相比,将批产星总装、集成与测试(AIT)周期由1年以上缩减为3个月以内,将发射场工作周期由35~50天缩减为20天,实现了快速研制、快速发射与快速在轨应用,有效促进了低轨小卫星星座高效规模化部署。 相似文献
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This paper summarizes the establishment and current development of space activities in the Bolivarian Republic of Venezuela. Space activities in Venezuela are focused on the areas of telecommunications, Earth observation and research on the physical properties of the Earth, and have as a primary goal the satisfaction of social needs. Current development of space activities started in 1999 when the new National Constitution recognized the value of outer space as the common heritage of mankind, and the key role of science and technology in promoting human welfare. The Bolivarian Agency for Space Activities (ABAE) was created in 2007. Its legal framework recognizes three key elements that drive its policy: the participation of society, capacity building and human training, and international cooperation. Indeed ongoing international cooperation with partners such as China, India, Brazil and Uruguay has already expanded Venezuelan space capabilities, allowing the country to launch its first telecommunications satellite, Venesat-1 in 2008, to plan the infrastructure development for the design of small satellites, and to train 1195 local professionals in space science, technology and applications. Our analysis shows that Venezuela has the potential to become a space leadership country, promoting the social welfare, integration, and sustainable development of Latin American countries. 相似文献
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科技信息研究是科技发展战略研究的基础,是科学决策的依据。文章归纳了科技信息研究中涉及的几个重要方面,包括科技信息研究在科技发展战略决策各环节中的作用、科技信息研究的选题检索、成果体现与评价的基本标准以及科技信息研究人员的素质要求等,得出了有关结论和启示。 相似文献
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面向卫星载荷小型化、集成化和多功能一体化的发展趋势,具有超宽带、高增益和波束灵活特性的天线是目前星载天线领域的研究热点,其可满足通信、干扰、侦察、探测等多种不同应用场景,具有十分迫切的需求。首先对不同形式的超宽带天线单元进行了归纳梳理,根据天线的机电特性和空间环境适应性情况,给出了星载应用选型建议;其次对不同的超宽带波束形成方式进行了阐述,重点分析了不同波束形成方式的优缺点及其在卫星平台上的适用性;总结了超宽带相控阵天线涉及到的关键技术,对主要的技术途径进行了介绍;最后对超宽带相控阵天线的星载应用技术发展提出了建议,可为我国后续开展星载超宽带相控阵天线的技术研究和工程应用提供参考。 相似文献
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