On April 12, 2017 (March 16, 2017 in the lunar calendar), our country's first Internet satellite was launched. The days when the first Internet satellite was launched without a signal on the train will be gone forever. At 19:04 on April 12, 2017, our country's first Internet satellite - Practice No. 13 was successfully launched by the Long March No. 3 B carrier rocket at the Xichang Satellite Launch Center, marking the beginning of the era of satellite Internet in our country. According to reports, Practice No. 13 satellite can realize seamless "mobile communication", which can connect the world for passengers on various means of transportation such as aviation, shipping, and railways, and completely improve the Internet experience. It takes less than 1 minute to download 1G data. The Dongfanghong No. 3 B platform is fully equipped with the first star. According to Zhou Zhicheng, the commander-in-chief of Shijian No. 13 satellite system, the "DongsanB platform" is the latest generation of medium-capacity communications satellite platform developed by our country. It adopts advanced technologies such as electric propulsion, high-efficiency thermal control, and lithium-ion batteries, which can rival the international advanced level. Shijian No. 13 applied a Ka-band multi-beam broadband communication system on our country's satellite for the first time, with a total communication capacity of more than 20Gbps (transmission speed rate unit, often referred to as "bandwidth"). The user end point can easily and quickly access the network, and the download and return rates can reach 150Mbps and 12Mbps respectively, which truly realizes the broadband application of satellite communication and fills the technical gap in this field in our country. " It takes less than 1 minute to download a movie at this speed of 1G. "According to Zhou Zhicheng, the practice of the 13th satellite has also created a number of" firsts "in the field of domestic high-orbit satellites: the first use of electric propulsion (without the consumption of chemical propellants) on our country's high-orbit satellites to complete the full life of the north-south location protection task, compared with chemical propulsion" less carrying a lot of chemical fuel ", the satellite carrying capacity has been significantly improved; the first time in our country's high-orbit satellites carrying a laser communication system; the first time in our country's high-orbit long-life communications satellite 100% engineering application of domestic products, changing the situation of long-term dependence on imports of related products. Improve the Internet experience of aircraft and railways According to statistics, the average daily air passengers in our country exceeds 1.20 million, and the average daily railway passenger volume reaches 7.60 million, but the Internet experience of passengers is very poor: Internet access is not available in the aircraft cabin, mobile phone signals on high-speed trains are intermittent, cruise ships become information islands after leaving the port, and passengers' demand for Internet access anytime, anywhere has not been met for a long time. Liu Fang, chief engineer of the No. 13 satellite project of the First Internet Satellite Launch Practice, said, "These problems are due to the fact that the ground mobile network cannot achieve full coverage, or even if it can be covered, it is too frequent to switch across different areas, making it difficult to provide services for high-speed transportation." According to him, the Practice No. 13 satellite adopts the design concept of integration of heaven and earth, and one of its important services is to provide high-speed "dynamic communication". Through multi-beam seamless switching and automatic tracking and capture function of airborne, vehicle-mounted or shipborne end points, it can connect the world for passengers on various means of transportation such as aviation, shipping, railways, etc., and completely improve the Internet experience. The Practice No. 13 satellite was developed by the China Aerospace Science and Technology Group company Fifth Academy. It is China's first high-throughput, electric propulsion engineering application communications satellite. It is also the first satellite of the East SanB platform with full configuration. It has undertaken tasks such as China's first high-speed laser communication test on a geosynchronous orbit satellite. The satellite has a lifespan of 15 years in orbit. The DongsanB platform is the latest generation of medium-capacity communications satellite platform developed by China, using advanced technologies such as integrated electronics, electric propulsion, high-efficiency thermal control, lithium-ion battery, FDIR, etc. The specific impulse of electric propulsion is more than 10 times that of conventional chemical propellants, which allows satellites to carry less propellant and provide more space for payloads. It can be said that the Shijian-13 satellite is a sign that China has entered the era of high-throughput satellite communications. In addition, this satellite will also be included in the "Zhongxing" satellite series, named Zhongxing-16 satellite. For the first time, China will combine satellite technology experiments and demonstration applications.