Development and Trends of Marine Space-Time Frame Network

Global space-time frame network is an infrastructure to acquire space-time information of the earth. It consists of three parts:ground, space and marine frame networks. Among them, the marine space-time frame network still sees its construction in an initial stage. This paper firstly defines the concept and connotation of marine space-time frame network and analyzes its development status quo and future trends from perspectives of marine positioning and navigation reference frame stations, and high-precision marine horizontal and vertical positioning reference frame stations. The major construction method of marine frame network is comprehensively utilizing GNSS(global navigation satellite system) positioning, underwater acoustic positioning and pressure sensor technologies to deliver the global unified space-time frame to surface layer, inside and bottom of the ocean. The construction of marine space-time frame network is still absent in China, so it should be pushed forward vigorously based on national realities and strategic planning. This paper points out:There is a universally great demand for global and national marine environment monitoring. However, the existing marine environment monitoring networks are mostly local networks and not integrated with space-time frame network, so space-time locations, changed slowly or rapidly, of marine environment cannot be clearly or accurately acquired. Therefore, it becomes imperative to integrate the construction of marine space-time frame network and marine environment monitoring network so as to achieve complementary improvement of benefits, efficiency and functions. Based on above mentioned, this paper deems that integrated marine frame network and marine environment monitoring network together with communication and data exchange functions can achieve the purpose of accurate marine environment monitoring and marine information transmission, and then with advancing gradually, global marine environment sensing and perceiving network with space-time location attributes i.e. Marine Internet of Things can be formed. Furthermore, this paper discusses assumptions:Marine Internet with space-time location attributes can be formed by linking Marine Internet of Things with seafloor communication cable and to communication satellites through buoy observation cabins on ocean surface. At last, this paper puts forward the opinion that China should accelerate its construction of a precise dynamic marine space-time frame and environment monitoring network that mainly focuses on its surrounding sea areas, and establish global marine space-time frame and environment monitoring network through conduction international cooperation.