The Beidou Satellite High-Precision Timing Applied Research

2014 ◽  
Vol 981 ◽  
pp. 381-385
Author(s):  
Zhao Peng Hu ◽  
Yu Hua ◽  
Shi Feng Li

The Beidou (BD) satellite navigation & orientation system is so important of national information infrastructure for our country. After research the BD system in the timing area, whlie analysed the advantage of the Beidou satellite timing technology compared with other conventional timing method, combined with high precision timing experiment and depending on the Common-view experimental results proved that the beidou statllite navigation & orientation system has high research value.

2020 ◽  
pp. 14-46
Author(s):  
A.M. MELNYK ◽  

It is proved that the satellite segment is a necessary component of the national information infrastructure. From this position, the state and development trends of satellite telecommunication systems and satellite channel organization technologies are analyzed. It is shown that there are two ways to build a satellite segment: based on the use of leased resources of satellite operators operating in the satellite communications market; based on the resources of the national satellite communications system, which still needs to be created. It is shown that satellite telecommunication systems have a steady tendency to increase the number of spacecraft, until the launch of “heavyˮ satellites with a payload of more than 70 transponders and to increase the frequency resource. The diagram of satellites location density of in orbit is given. In the case of orientation to rent the resources of active spacecraft, the criteria for their selection is indicated. The arc of the geostationary orbit, on which the satellite should be selected, is calculated. For satellites located on this arc, diagrams of equivalent isotropically radiated power values in the C and Ku bands, which they provide in Ukraine, are shown. A list of satellites that you can focus on, recommendations for selection and a list of recommended for the satellite segment is indicated. The technology standards used in payload and methods for organizing satellite communications channels is noticed. To select the parameters of the satellite segment, the results of calculations of the effectiveness of signal-code structures are provided. Approaches to creating a satellite segment of the national information infrastructure are proposed. It is shown that the orientation to the Lybid national satellite does not make sense; a new frequency-orbit resource is required. The types of platforms that can be used on a national satellite are considered.


Author(s):  
Ook Lee

ENI Company is an electronic commerce firm in South Korea. ENI Company provides English news items and English lessons to the subscribers through daily e-mail service that includes free English news-related question and answer sessions via e-mail. This case study deals with the struggle of this firm to establish and sustain its business in a less-developed national information infrastructure. Information on national information infrastructure and the Internet in South Korea is provided in order to facilitate understanding of the difficulty that ENI Company faces while conducting e-commerce in South Korea. The chronology of ENI Company evolution is described and the organizational structure of ENI Company is also presented. The marketing of ENI Company’s products that is the biggest challenge for the firm is also discussed. This case is a good example of how to conduct an e-commerce in a county where national IT infrastructure is not ready for it.


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