# Cross-Domain Fusion Constellation Design of Communication, Navigation and Remote Sensing
###### Abstract  
Low earth orbit (LEO) mega-constellations have once again triggered a wave of space-based system construction. On the one hand, LEO communication, LEO navigation, LEO remote sensing constellations and so on are proposed. On the other hand, with the continuous development of software-defined satellite and intelligent satellite technology, space-based systems are developing in the direction of multi-function, integration and cross-domain integration. The whole space-based system is no longer the traditional working mode of a single functional constellation, but a general cross-domain fusion constellation (CDFC) system for complex tasks. Like the terrestrial global Internet, the space-based system will serve as a global infrastructure for integrating communication, navigation and remote sensing, that is, the intelligent space-based system, to provide services for the global demand. The traditional method of designing constellation for a certain type of function is no longer applicable to this type of constellation design. To solve this problem, this paper proposes a design and optimization method of cross-domain fusion constellation of communication, navigation and remote sensing based on reverse design. The paper optimizes the CDFC through resource coverage. Through experiments, we prove that the number of satellites in the CDFC can be reduced by 30.60% compared with the independent and combined constellations in each domain, and the coverage and service performance of the constellation can be improved. The cost can be reduced by 18.31% compared with the combined constellation. When the same number of satellites is used, the resource coverage of the cross-domain fusion constellation is increased by at least eight times. cross-domain integration constellation; multidisciplinary cooperation; reverse optimization; integrated service +
Footnote †: journal: Medical Imaging  
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Footnote †: journal: Medical Imaging  
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Footnote 1: email: {q  
functions, explosion of computing space, mutual coupling of system variables, etc. [6; 7; 8; 9; 10; 11; 12; 13; 14]. CDFCs are different from hybrid constellations. Hybrid constellations are aimed to improve services by optimizing orbits [6] to meet different user needs [7] or different coverage requirements [8]. They all discuss service optimization in the same functional domain, while CDFCs need to consider multiple functional domains. [PERSON] et al. presented a special case of an integrated constellation based on coverage characteristics for the comprehensive application requirements of communication, navigation and remote sensing [9]. For CDFC, it is necessary to consider the parameters of each functional domain and their relationship more comprehensively. It is a multi-objective fusion design problem [10]. In traditional multi-objective constellation design, simplex algorithm [11] and semi-analytical method [12] intelligent algorithms such as genetic algorithm [3; 13], multidisciplinary design optimization (MDO) method [10; 14] and so on are widely used. The problem with the above algorithms is that CDFC cannot directly use analytical expressions. The genetic algorithm is only applied to a single discipline or field. The multidisciplinary design optimization method is a method to solve the dynamic influence of multidisciplinary methods in complex engineering system design and realize the system optimization design. However, when this method is used in constellation design, and is different disciplines in a single domain, such as structure and orbit dynamics [14]. Based on the above challenges, we put forward the concept of CDFC and the design method of multidisciplinary collaborative reverse optimization (MDCRO). The contributions of this paper are summarized as:  
* A concept of CDFC based on software-defined satellite for communication, navigation, remote sensing and other different functional domains is proposed.