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1.
The first part of the paper describes the structure of the analytical cost estimation model (1982 edition) for launch vehicle development, fabrication and launch operations cost. Especially the new approach for a cost assessment of operations cost including refurbishment (in case of reusable vehicles), direct and indirect operations is presented for discussion and subsequent improvements by introduction of more reference values. The model uses the Man-Year (MY) as cost unit which is independent from inflation and currency exchange rate changes.

The second part of the paper deals with its application to future systems analysis and cost comparison with the example of a potential future European launcher (Post-Ariane-4) with 15 tons LEO payload capability: ten different two-stage launch vehicle concepts (expendable, semi-reusable and fully reusable) with storable and cryogenic propellants are analysed with respect to development cost and cost per launch.

The key problem for a future European launch vehicle is the optimum solution between the (limited) development effort and the desired minimum launch cost. More advanced (partially) reusable systems could provide an essential reduction in cost per launch, require, however, a higher development effort.

In such a case an analytical cost model based on realistic reference data can provide important data for the vehicle concept selection process.  相似文献   


2.
近几年,随着小卫星市场的蓬勃发展,小型卫星发射市场持续升温,以飞马座XL和运载器一号火箭为代表的空射火箭完成多次发射任务,将数十颗卫星送入近地轨道。空射运载火箭具备快速响应、机动灵活、发射成本低、任务适应性强等技术特点。运载火箭从空中发射可以充分利用载机的飞行高度和飞行速度,在相同的系统运载能力下,火箭的起飞质量更小;在相同的火箭起飞质量下,系统运载能力更高;同时,对于规模星座快速部署,空中发射的灵活优势显著。围绕空射火箭的上述技术特点,基于空射火箭模型开展仿真分析研究及不同发射方式的结果对比,结果表明空射方式对提升系统效益效果显著。  相似文献   

3.
This paper proposes a complete model for assessing the economics of telecommunications satellite systems, accounting for spacecraft development and manufacturing, launch and operations in orbit. This allows to account for such parameters as the mass and lifetime of the satellites, the number and type of payloads, the number of satellites procured and launched, the spare policy, the launch vehicle, the insurances, the satellite average MTTF and the management of the space segment efforts.

The model is divided into four parts: the spacecraft mass model, the spacecraft procurement cost model, the MTTF model and the space segment cost-effectiveness model. It provides for the rapid solution of a number of problems within a wide range of parameters such as assessing the influence on space segment economics of —certain satellite technologies, —satellite and payload mass, —number of payloads per spacecraft, —satellite lifetime, or —spare policy.  相似文献   


4.
The development of sea state monitoring from polar-orbiting satellites has recently moved away from the concept of single, multi-sensor platform such as ERS-2, Topex/Poseidon or ENVISAT towards the design of a system that would allow frequent updates from a constellation of small satellites equipped with special-purpose radar altimeters. This new system, called GANDER for Global Altimeter Network Designed to Evaluate Risk, has attracted significant support from a number of important customer segments including the military.

This paper details the design of an altimeter for a Surrey small satellite, and illustrates the major system trade-offs that need to be made. Critical to the viability of the mission will be the development of a radar altimeter capable of operating successfully on a small satellite bus, within a limited volume and power budget. The mission design presents a number of key technological challenges, in order to permit a physically small antenna to be employed, and to minimise the pulse power. This can be achieved by advanced techniques, such as the delay Doppler altimeter concept, which emphasises the needs for high-speed on-board signal processing, phase linearity and pulse-to-pulse phase coherency.

The system design for the GANDER constellation is also described, illustrating how it not only offers a means for maritime disaster mitigation, but also can reduce shipping cost and time.  相似文献   


5.
A reusable launch vehicle could be developed early next century if the X-33 program is successful. Its development will be funded by industry, and the vehicle will be operated privately. A critical task is to assess the future market for such a vehicle. The total number of commercial payloads could range between 40 and 60 satellites per year, taking into account the market elasticity due to the launch price reduction. The RLV would face important competition from expendable launch vehicles. However, the RLV could capture two-thirds of this market, or 26–33 commercial payloads per year.  相似文献   

6.
32颗GPS卫星星座空间覆盖特性建模与仿真   总被引:1,自引:0,他引:1  
GPS卫星要准确完成定位功能可见卫星数应不少于4颗.通过建立针对低轨、中高轨和大椭圆轨道目标卫星的GPS信号空间几何覆盖模型,利用Matlab计算针对低轨、中高轨和大椭圆轨道的可见卫星数,对目前美国32颗GPS卫星星座的空间覆盖特性进行仿真.仿真结果显示,32颗GPS卫星星座不仅可以对低轨目标实现全轨道覆盖,而且对中高轨和大椭圆轨道也有所覆盖,大大扩展了24颗GPS卫星星座的空间应用.  相似文献   

7.
Following the successful maiden flight of the Long March 11(LM-11) launch vehicle from the Jiuquan Satellite Launch Center in September 2015, the first sea-launched carrier rocket dedicated to provide a launch service for small satellites and their constellations, the Long March 11 Sea Launch(LM-11 SL) has been under development by the China Academy of Launch Vehicle Technology(CALT) and the China Great Wall Industry Corporation(CGWIC). It is planned to commence launch service in 2018. Based on the LM-11, a land-launched four-staged solid launch vehicle which has entered the market and accomplished launch missions for several small satellites in the past 3 years, the newly adopted sea launch technology enables transport and launch of LM-11 SL from maritime ships, providing flexible launch location selection.After inheriting the mature launch vehicle technologies from previous members of the Long March launch vehicle family and adopting a new way of launching from the sea, the LM-11 SL is capable of sending payloads into low Earth orbits with all altitudes and inclinations, from 200 km to 1000 km, from equatorial to sun synchronous, within a shortduration launch campaign. The LM-11 SL provides a flexible, reliable and economical launch service for the global small satellite industry.  相似文献   

8.
This paper analyzes the launch price of the launch vehicles, domestic and abroad, studies the status and trend of the low cost launch vehicles, and introduces two measures to reduce the cost by means of evolved and disruptive technologies, utilizing the concept of low cost manufacturing and operating modes as well. This paper also analyzes the launch strategies for small satellites such as piggyback, networking launch, and single launch with a small launch vehicle(SLV). Finally, the development trend of reusable launch vehicles is discussed as well as the development prospects for China's reusable launch vehicle.  相似文献   

9.
为飞机等交通工具内的用户提供基于卫星的不间断IP连接,并在卫星星座网络内实现IP路由选择功能,是未来LEO卫星星座通信网络需要解决的关键问题。提出了基于移动式网络技术的LEO卫星星座通信网络体系结构,实现了卫星星座通信网络中的IP路由选择功能,并降低了对地面网路的依赖,实现了对用户段网络随时随地的连接支持。在对卫星星座通信网络中的星地切换模式进行分析的基础上,提出了一种基于虚拟移动路由器的快速星地切换和认证方法。通过NS2仿真试验,给出了新型LEO卫星星座通信网络的传输延迟特性以及快速切换方法的仿真试验结果。仿真试验表明,提出的网络结构是满足未来卫星星座发展需求的,星地间的切换是低时延的。  相似文献   

10.
The Smart Dragon 1(SD-1) launch vehicle is the first commercial rocket developed by China Academy of Launch Vehicle Technology(CALT), targeting to the international launch market for small satellites. As the smallest launch vehicle in China at present, SD-1 is one of the most efficient solid boost rockets nationwide in terms of launch capacity. Compared with current domestic rockets, it provides remarkable access to space with a faster response, higher orbit-injection accuracy and better payload accommodation at a lower cost. On August 17, 2019, SD-1 completed its maiden flight and delivered three satellites into the desired Sun Synchronous Orbit(SSO) of 550 km accurately. In this article, a technical review of SD-1 is presented detailing the design concept and the use of state of the art technology throughout its development.  相似文献   

11.
以我国现有固体火箭发动机为动力装置,以带翼的三级固体运载火箭分析模型为依据,探讨机载火箭发射小型低轨卫星的可行性和现实性。  相似文献   

12.
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   

13.
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   

14.
This paper introduces a launch vehicle scheme for the new generation of cryogenic and quick-launch launch vehicle(LM-6). The main technical innovations of LM-6 launch vehicle include the capability of twenty satellites launched by one vehicle, high-pressure staged combustion cycle engine and oxygen tank self-pressurization, sandwich bulkhead tank with 200 K temperature difference, and 7-day quick-launch using the "three horizontals" test and launch mode with integral transportation and erection. The future development of the quick-launch launch vehicle is predicted based upon the need for vehicle mission coverage improvement, better response speed, and stronger market competiveness.  相似文献   

15.
陈雨  赵灵峰  刘会杰  李立  刘洁 《宇航学报》2019,40(11):1296-1303
针对低轨(LEO)Walker星座构型维持问题,分析在地球非球形引力和大气阻力摄动下卫星的运动规律及星座构型演化特性。结果表明,低轨Walker星座构型发散主要体现在由初始轨道参数不一致引起的轨道高度衰减和相位漂移,国内首例低轨Walker星座实测轨道数据验证了理论分析的正确性。结合星座任务特性与构型发散特点,提出了基于基准卫星的相对相位维持策略,选取一颗卫星作为基准卫星,使星座中其它所有卫星相对于基准卫星的相位漂移量累加值最小,通过对目标卫星实施一次相对基准卫星的轨道高度抬升/降低,维持星间的相对位置关系。实际工程应用表明了此策略的有效性,不仅降低星座构型维持的复杂度及频次,节约燃料,且轨控时间短,为我国今后卫星星座的构型维持提供参考。  相似文献   

16.
针对低轨同构星座覆盖资源在纬度上分布不均匀的不足,提出采用低轨混合星座提升覆盖均匀性的设计方案,并推导了满足全球任意点平均每天覆盖一定次数的最小卫星规模估算公式。针对非支配近邻免疫算法(NNIA)约束处理方面的不足,提出基于约束支配的改进非支配近邻免疫算法(Modified NNIA),并以此设计了一种低轨混合星座优化平台来优化带约束的星座设计问题。仿真结果表明,改进的NNIA算法在收敛速度和多样性上均优于非支配分层遗传算法(NSGA II)和多目标粒子群算法(MOPSO),可大大提高星座设计的效率。同时优化结果也表明低轨混合星座可提高覆盖的均匀性和大部分区域的覆盖次数,进而减少特定覆盖要求所需的卫星数目。  相似文献   

17.
高晓颖 《航天控制》2004,22(3):23-25
陆基移动发射小型运载器不依赖大型、复杂的地面支持系统 ,系统简单 ,可以根据轨道以及相关限制因素需要选择最佳发射地点与控制程序 ,进而大幅度降低发射成本、有效的提高运载能力。本文根据上述特点 ,基于惯性 /卫星组合技术研究了制导控制方案 ,可以实现行进中瞄准与快速发射 ,并以近地轨道卫星发射为范例进行仿真计算。  相似文献   

18.
19.
天基红外低轨星座对目标的跟踪算法研究   总被引:2,自引:1,他引:2  
谢恺  薛模根  周一宇  安玮 《宇航学报》2007,28(3):694-701
建立了天基红外低轨星座对自由段目标的观测模型,考虑了精确的目标运动模型。针对天基红外低轨星座的任务特点,从收敛速度、估计精度、估计有效性以及运算效率等方面比较了批处理滤波、EKF、UKF、高阶UKF和粒子滤波等算法的性能。仿真结果表明,综合考虑各种因素的影响,UKF具有最佳估计性能,能够对天基红外低轨星座中自由段目标进行有效跟踪。该文的理论分析和仿真实验对天基红外低轨星座的跟踪滤波器设计具有重要的指导意义。  相似文献   

20.
一种低轨卫星星座覆盖性能通用评价准则   总被引:2,自引:0,他引:2  
针对不同构形卫星星座的统一评价问题,提出了一种低轨星座覆盖性能的通用评价准则,可对不同构形和不同高度的星座对地覆盖性能进行统一评价。该准则将星座的对地仰角特性转化为具有相同覆盖能力的标准卫星数,以之同星座中实际卫星数的比值作为星座覆盖性能指数对星座实施评价。利用该评价准则,计算了Iridium、Globalstar、Celestri和NeLS四种星座构形覆盖性能的评价指数并提出了改进方法。  相似文献   

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