New method of reliability analysis and calculation on grey maintainable system
A new model for reliability analysis and calculation of the grey maintainable system is put forward based on the grey theory to tackle the problem of lacking information for practical application. The feasibility of the proposed method is confirmed by a numerical example. The feature of this new method is that it can analyze system reliability dynamically and master its development law because it does not depend on the distribution parameters of system. Hence, it can be used to preview the reliability of system.
On air defense communications network connectivity
The authors address the issue of communication network survivability and provide a quantitative measure of the time-varying connectivity of space and ground multimedia networks operating in stressed environments. This measure allows comparison of very different network architectures in terms of connectivity. A generic SBR (Space-Based Radar) constellation was selected for study of the communications connectivity. The SBR, consisting of constellations of low Earth orbit satellites, will require dynamic, robust communication protocols and networks to support the various missions for the Air Force, Navy, and other military organizations. The authors present a methodology that can be used to define connectivity requirements once the threat and system parameters are better defined.<<ETX>>
Space based radar application to air traffic control
Future control of increasing air traffic on international routes will require significant advances in techniques employed. Development is underway, but at this time does not include addition of radar coverage of vast areas of oceanic traffic. This paper addresses the potential for a space-based radar to provide detection and track of aircraft in future traffic scenarios. Factors that must be considered in further tradeoff and concept optimization are discussed. These include: (1) satellite constellation characteristics and associated coverage, (2) efficient use of available energy in track-while-scan strategies, (3) development of tracker approaches to accommodate inherent system constraints, and (4) the application of transponders to assist in dense traffic environments. The analysis assumes the continued development and availability of technology required for high spacecraft power systems (hundreds of kilowatts), and for radar subclutter visibility.