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Parts of a study conducted to examine state-of-the-art power systems applicable to future military spacecraft are summarized. The study focused on burst-mode megawatt-class CW power, such as might be applied to SDIO directed energy systems, but lower-power, continuous-duty subsystems were included in less detail. A set of simple mass and volume algorithms has been developed to approximate several prime systems, and these were incorporated into a Lotus 1-2-3 spreadsheet. Among the power subsystems included in that study were primary batteries, alkaline primary fuel cells, and combustion turbogenerators. These systems, which are the most likely candidates for mobile battlefield power, are described 相似文献
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Performance comparison of PRF schedules for medium PRF radar 总被引:1,自引:0,他引:1
Wiley D. Parry S. Alabaster C. Hughes E. 《IEEE transactions on aerospace and electronic systems》2006,42(2):601-611
Previous work has shown how evolutionary algorithms (EAs) are an effective tool in optimising the selection of pulse repetition frequency (PRF) values of medium PRF schedules in an airborne fire control radar (FCR) application requiring target data in three PRFs. The optimisation is driven by the requirement to minimise range/Doppler blindness whilst maintaining full decodability. In this paper we detail work in which the optimisation process is applied to design novel short medium PRF schedules requiring target data in just two PRFs. The paper reports on the testing of a variety of near-optimum schedules to compare their blindness, decoding, and ghosting performances. The results show that in many situations, the 2 of N schedules are a practical alternative to conventional 3 of N processing. 相似文献
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James C. Leary Richard F. Conde George Dakermanji Carl S. Engelbrecht Carl J. Ercol Karl B. Fielhauer David G. Grant Theodore J. Hartka Tracy A. Hill Stephen E. Jaskulek Mary A. Mirantes Larry E. Mosher Michael V. Paul David F. Persons Elliot H. Rodberg Dipak K. Srinivasan Robin M. Vaughan Samuel R. Wiley 《Space Science Reviews》2007,131(1-4):187-217
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft was designed and constructed to withstand the harsh environments associated with achieving and operating in Mercury
orbit. The system can be divided into eight subsystems: structures and mechanisms (e.g., the composite core structure, aluminum
launch vehicle adapter, and deployables), propulsion (e.g., the state-of-the-art titanium fuel tanks, thruster modules, and
associated plumbing), thermal (e.g., the ceramic-cloth sunshade, heaters, and radiators), power (e.g., solar arrays, battery,
and controlling electronics), avionics (e.g., the processors, solid-state recorder, and data handling electronics), software
(e.g., processor-supported code that performs commanding, data handling, and spacecraft control), guidance and control (e.g.,
attitude sensors including star cameras and Sun sensors integrated with controllers including reaction wheels), radio frequency
telecommunications (e.g., the spacecraft antenna suites and supporting electronics), and payload (e.g., the science instruments
and supporting processors). This system architecture went through an extensive (nearly four-year) development and testing
effort that provided the team with confidence that all mission goals will be achieved.
Larry E. Mosher passed away during the preparation of this paper. 相似文献
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Synthetic Aperture Radars 总被引:1,自引:0,他引:1
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