A Study On Vulnerability Of Satellite Application Systems

The technology of satellite communications, satellite remote sensing and satellite navigation is being used from scientific research to the public application and promoting satellite application industry to be a strategic emerging industry. As the carrier of combination of satellite technology and business operations, satellite application is a complex high-tech electronic information system. For satellite application systems, there are technical constraints, system failures and external security threats and other risk factors during the technical operation. In the process of system planning, development and commercial operations, satellite application systems are also facing the risk of political, economic, development, management and other aspects.Traditional research on system risks is mainly based on the reliability theory and risk management theory. Using reliable methods are difficult to fully consider the impact of human factors, the sudden threat factors when evaluating complex systems. And using risk management theory is emphasizing on external factors and neglect factor analysis of the system. When the vulnerability of the system is used to characterize the degree of external threats and the ability of adaption or recover, it is considering the characteristics of the system of internal and external risk factors that can effectively explain the system capacity to respond to the issue of risk.Firstly, the review of the research of vulnerability domestic and abroad of satellite application technology and industrial risks are given. For system operation efficiency and system life indicators, the concepts of technical and non-technical vulnerabilities of satellite application systems are proposed. Then, by analyzing the typical satellite application system architecture and performance characteristics, the general model of features and structures for the system is developed. According to the system efficacy theory and equipment life-cycle theory, the principle of the effectiveness distribution of satellite application system is given. Combined with the features of satellite application industry model, the indexes of effectiveness distribution and longevity index distribution of satellite application systems are established. And based on the theoretical model of "risk-Vulnerability- risk consequences", the corresponding indexes system of technical and non-technical vulnerability indicators of the system are constructed.Finally, based on technical and non-technical vulnerabilities of the system model, the concept of vulnerability path is proposed, which is from "risk- Effectiveness(life)-System" link. Thenthe relatively fragileis found through contrasting the different paths. The structural components of the system or the various stages of the whole life cycle can be seen as a system node. The contribution of the system node for efficacy(life) is presented by indicators of efficacy(life) assigned weighting factors. And the impactof the risk factors affecting the system node is represented by the risk weighting factor. Mathematical models of two weighting factors for the main parameters are developed to achieve different paths to quantify and assess the vulnerability of the system. The reasonableness and practicability of the assessment methods are verified by engineering examples.Vulnerability theory is a new theory in the study of the characteristics of complex systems. There have been some scholars applying the theory in aerospace and other fields. From their research, the main innovations of this thesis are as follows:I. The theory of vulnerability is introduced into the field of satellite application technology research and industry. The vulnerability model of satellite application system based on risk theory is developed;II. Combining with traditional satellite application technology and its developing trends, a unified definition of satellite applications is presented. And the general structural model of satellite application system is developed;III. According to system performance theory and the whole life-cycle theory of equipments, the technical vulnerability system based on performance indicators and the non-technical vulnerability theory of the life indicators are established. It makes the vulnerability theory more realistic that combining the vulnerability theory with the effectiveness of system operation;IV. Combining subjective and objective weighting methods, a set of comprehensive method to assess the system vulnerability is established, which blends the differences between subjective information from specialists and objective attributed indexes. Moreover, based on binary semantic grey relational analysis method is proposed, and the system vulnerabilities of different schemes are compared. Finally, more satisfactory results in engineering applications are achieved.