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Competition between the providers of space transportation has become intense with the distinct possibility of governments providing both direct and indirect subsidies in order to influence transportation user choices. This bodes well for users of transportation services but has serious ramifications with regard to the future makeup of the international space transportation industry. This paper addresses the following key issues: selecting a launch service given a decision to establish a business to provide satellite communication services; establishing the price that should be bid by a launch provider in order to have a specified chance of being awarded the launch contract; and assessing the possibility that a launch provider is utilizing unfair or predatory pricing in order to increase the likelihood of winning launch contracts and thereby increasing market share. A method is developed and results presented based upon establishing ‘value in use’ pricing that explicitly takes into account the multiple attributes of alternative launch services. This leads to an assessment of ‘predatory’ pricing in terms of the value in use pricing.  相似文献   

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在研究欧洲电信标准化协会(ETSI)卫星测控系列标准的基础上,针对我国商业卫星测控的现状与特点,对国内商业卫星的测控体制进行初步的探讨和研究,包括调制体制、测量方式、数据帧结构及典型应用场景分析等方面。  相似文献   

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全电推商业卫星平台研究综述   总被引:1,自引:0,他引:1  
左坤  王敏  李敏  汤海滨 《火箭推进》2015,41(2):13-20
近年来,电推进技术在空间推进中的应用越来越普遍,电推进系统主要应用于低地球轨道、同步地球轨道和星际任务三个方面。在轨道转移过程中,与传统双组元化学推进系统需消耗数吨推进剂相比,全电推进完成从地球转移轨道到同步地球轨道的变轨过程仅需数百千克推进剂,从而能够有效降低发射质量,显著提高商业效益。基于全电推进的商业卫星平台能够较大限度地提升卫星荷载比、充分发挥卫星平台承载能力,并提升卫星平台综合性能。从调研电推进系统研制和应用现状入手,介绍了国外全电推商业卫星平台开发情况,借鉴国外发展模式并结合我国电推力器研制基础和能力,提出了国内全电推商业卫星平台总体方案。  相似文献   

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The commercial launch industry is maturing into an international market that is highly price competitive. A common way to deal with the high cost of launch services is to use a single booster to place several payloads into orbit. This practice requires the launch provider to divide the cost of the shared mission between the customers. Unfortunately, the methods normally used to do this are inadequate. This paper addresses the question of how best to share launch costs. It examines the existing methods and introduces two alternative methods for this purpose. The new methods are demonstrated and shown to be superior.  相似文献   

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国内外卫星用液体远地点发动机发展综述   总被引:2,自引:0,他引:2  
综述了国内外卫星用液体远地点发动机的发展情况,阐述了国外几种典型远地点发动机和国内三代490 N发动机的主要技术特点和技术指标,对比分析了其产品性能并介绍了其产品的考核应用情况。自上世纪90年代以来,国内外在卫星用液体远地点发动机的研制中喷注器性能不断提高,推力室均采用了新型抗高温氧化材料,主要以铼/铱材料和C/SiC...  相似文献   

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Ryan J. Zelnio   《Space Policy》2007,23(4):221-233
Within a global economy, export controls play a large role in hindering the proliferation of high technology. A company operating in a country that operates under more strict export controls than others is at a serious disadvantage in competing. This has been the case for commercial satellite (comsat) manufacturers in the USA since 1999, when Congress redefined comsats and all technologies associated with them from a dual-use export under the jurisdiction of the Department of Commerce to a munitions export that falls under the jurisdiction of the Department of State. Following this, there was a drastic drop in the market share of US comsat manufacturers in comparison to European manufacturers, who continued to define satellites as a dual-use technology. This paper examines the various factors that have affected US industry competitiveness and tackles the question of whether or not it continues to make sense to keep comsats under the more restrictive International Traffic in Arms Regulations (ITAR) controls. To accomplish this, comsats are subjected to a litmus test created by George Zaphiriou in 1992 to determine whether a technology should be placed under ITAR controls.  相似文献   

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Satellite services benefit civil society by helping tackle challenges such as climate change, the digital divide, etc. They have the potential to deliver concrete benefits to European society through innovative services supporting economic, societal and environmental policies. Such benefits can trigger increased public support for space in Europe. However, this potential has yet to be achieved. This paper argues that technological bias, the diversity of interests and initiatives among stakeholders and their individual actions do not always serve their collective objective to ensure wide diffusion of satellite services. It draws on theories of diffusion of innovation and on its authors' participatory work with the space and the user communities and at their interface in an effort to help diffuse satellite services within civil society. One of the major causes of insufficient service diffusion is the weakness of the interface between the space and user communities; some of factors that currently contribute to this state of affairs are the space community's over-reliance on publicly financed, technical demonstration projects as solutions to service diffusion; insufficient coordination by public authorities of innovation policies and programmes with other public policies and objectives; and an insufficient integration of satellite services within users' culture, traditional tools and services. The discussion allows for conclusions to be drawn on how the system of stakeholders could function better in order for satellite services to be successfully diffused in Europe.  相似文献   

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A Canadian Government program is currently under way to define, in detail, services and applications, user requirements, end-to-end system architecture and subsystem equipment design requirements for a demonstration on-board-processing (OBP) communications satellite system. The program has reached an advanced stage of definition. The prime directive of the overall mission is to provide demonstration and development of technology and services.

This paper begins by describing the development of our understanding of the true scope of advanced personal communications services and applications; the user expectations and hence terminal characteristics are also reviewed in the context of the competitive environment of other service offerings both existing and planned. In addition, the results of considerations on spacecraft complexity and hence feasibility, caused by the impact of each service option and the requirements for internetworking, are reviewed.  相似文献   


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卫星天线产品在进入轨道工作之前需要在地面进行模拟空间环境的高低温热变形测量。文章依据测量设备所处环境及测量方式将卫星天线高低温热变形测量划分为常压高低温测量和真空高低温测量,介绍了真空罐和常压高低温箱测量方式的工作模式及应用范围。此外,还对高低温热变形测量的特点、误差影响因素、现存的问题做了介绍和讨论。最后对卫星天线高低温热变形测量的未来重点研究方向给出建议。  相似文献   

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某型号小卫星发射时,用搭载的测量系统对星上6个测点位置进行了3个方向的振动响应测量,获得了主动段2000 Hz范围内的完整数据。数据分析表明,小卫星主动段的振动模态特性和振动响应特性不同于地面模拟试验中的结果,主要体现在:主动段40 Hz处的Pogo效应明显;共振频率与地面试验完全不同;横向响应量级明显小于纵向响应量级;在小于2000 Hz频率范围内,星箭分离冲击对星上测点位置影响很小。与地面试验数据的对比分析结果表明,目前的地面振动试验方法仍有不足,存在过试验或欠试验。  相似文献   

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某型号卫星磁性分析与控制   总被引:1,自引:0,他引:1  
某型号卫星的有效载荷之一高能望远镜对磁场敏感,因此在设计阶段即需分析卫星在轨时载荷所处的磁场环境,并尽可能提高载荷的抗磁场干扰能力。文章根据卫星的构型,对整星的磁场分布进行了计算;对载荷的抗磁场干扰能力进行了测试;对载荷的磁屏蔽方案进行了仿真与测试;分析了抗磁场干扰设计对整星磁性控制的影响,证明卫星可以满足总磁矩不大于5.0 A?m2的姿态控制要求。  相似文献   

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海洋卫星AIS载荷设计与验证   总被引:1,自引:1,他引:0  
为实现全球海洋船舶位置监视,用户在我国海洋系列卫星上配置了船舶自动识别系统(automatic identification system, AIS)。卫星AIS覆盖范围大,面临严重的信号碰撞问题,且AIS工作频段低,易受卫星平台低频干扰影响。用户及卫星总体要求AIS载荷提升对卫星电磁环境适应性以降低卫星AIS频段电磁环境净化代价,同时具备一定近海海域接收能力。在深入分析卫星电磁环境工况及近海AIS信号碰撞工况基础上,提出了AIS载荷阵列天线设计、抗卫星电磁干扰设计、低信噪比解调设计为主的针对性设计,相关设计已经通过海洋二号C卫星在轨验证,对其他卫星AIS载荷设计具有较好的参考意义。  相似文献   

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可视电话发展至今已经有几十年,也并不局限于一体机的形式,还有了机顶盒以及软件形式.可视电话可以实现远端见面,为人们的生活和工作提供了很多方便.随着网络的普及以及IP的发展,可视电话将有一个广阔的发展空间.  相似文献   

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This is the executive summary of a report prepared for the European Commission by LD consultants on the status of India's space industry and the prospects for European firms to invest in it. India has impressive launch capabilities, telecommunications and disaster warning satellites but commercialization of its activities is occurring only slowly. There are many opportunities for joint ventures with Europe (which must not let the USA consolidate its superior position in the broadcasting field) but issues of technology transfer and India's unhappiness with the MTRC must first be resolved. As well as selling products and services, Europeans should also be prepared to buy those Indian components that are available more competitively.  相似文献   

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可视电话发展至今已经有几十年,也并不局限于一体机的形式,还有了机顶盒以及软件形式。可视电话可以实现远端见面,为人们的生活和工作提供了很多方便。随着网络的普及以及IP的发展,可视电话将有一个广阔的发展空间。  相似文献   

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某卫星微振动建模与仿真   总被引:5,自引:3,他引:5  
针对某卫星微振动力学环境,参考IME颤振分析建模方法,建立了一种卫星刚柔耦合多体动力学微振动仿真模型,并通过地面试验验证了利用微振动仿真模型预测卫星在轨微振动响应的有效性,阐述了卫星在轨微振动响应仿真计算预测方法。利用该微振动仿真模型能较准确地预测卫星在轨微振动响应以及微振动传递特性。  相似文献   

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The London Institute of Space Policy and Law is presenting a series of seminars on risks associated with space activity and its insurance, aimed at fostering better understanding of the risks particular to commercial space projects, and at encouraging appropriate policy measures. Seminar IV-I on 5 February 2010 focused on policy and regulatory risk considerations for satellite communications. After an introduction by the seminar chair Jeremy Rose, senior consultant at telecommunications consultancy Comsys, and a welcome from Institute Director Sa'id Mosteshar, four speakers outlined the ideal regulatory framework for satellite communications, as well as current regulatory and policy risks at the international, regional and national level. Risks were discussed in ITU, EU and UK procedures and policies and debate was continued from the floor. The event's rapporteur summarizes the issues highlighted by the speakers and some of the interventions from the floor.  相似文献   

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