What other satellites do you know? What are their respective functions?

Satellite refers to a natural celestial body that runs around the planet and periodically in a closed orbit. Satellites can also be called satellites in general. Man-made satellites are devices built by human beings, which are launched into space by spacecraft such as rockets and space shuttles, and orbit around the earth or other planets like natural satellites.

Classification and function:

Among these successfully launched satellites, there are satellites used for scientific and technological experimental investigation, communication, meteorology, navigation, earth resources, military reconnaissance, ocean surveillance, early warning, data relay, military geodesy and other purposes. They have made great achievements in their respective fields, which have revolutionized human traditional civilization and military technology.

According to expert statistics at the end of 1989, among all kinds of satellites that have been successfully launched, except for military and scientific research experiments, there are 1093 satellites for civil communication, broadcasting, meteorology, navigation and earth resources, accounting for 27.6% of the total number of launching countries. Among them, there are 658 communication and broadcasting satellites, 63 meteorological satellites 163, 239 navigation satellites and 33 earth resources satellites. The working life of these satellites is very limited, most of them are 1 ~ 2 years, and the longest is no more than 10 years. According to the design life statistics, there are not many application satellites still in orbit. In fact, the application satellites launched before 1983 have basically stopped working. There are about 200 in orbit, no more than 400 at most.

By 1992, more than 20 countries have added more than 4,000 such new members to the cosmic family, accounting for 90% of all kinds of spacecraft launches, and China has also added 33 new partners to the cosmic family. Eight countries (Russia, the United States, France, Japan, China, Britain, India and Israel) have independently developed and launched artificial satellites, while more than 20 countries and regions have developed their own satellites, and more than 65,438+000 countries and regions have become members of the International Telecommunications Satellite Organization.

China's mainstream satellites;

Sinosat-2:

Xinnuo-2 satellite mainly serves communication and broadcasting users in Chinese mainland, Hong Kong, Macao and Taiwan. The satellite adopts the public platform of a new generation of large-scale geostationary satellites being developed in China, namely the Dongfanghong-4 satellite platform, and carries 22 Ku-band high-power transponders. At the end of the satellite life, the output power is 10500W, the launch weight is 5 100kg (Dongfanghong-3 is a medium-capacity communication satellite, which can carry 200 kg payload, and the whole satellite power is 1800 W, which can carry 24-way lieutenant colonel power transponders), and the design life is 15 years. Launched by xichang satellite launch center on the Long March CZ-3B carrier rocket, the whole satellite index and capability reached the international advanced level.

The platform is composed of power supply, measurement and control, data management, attitude and orbit control, propulsion, structure and mechanism, thermal control and other subsystems, with a full three-axis stable control mode. The total output power of the platform is 8000- 10000 watts, which can be extended to more than 10000 watts and can provide about 6000-8000 watts for the payload. The platform can carry 600-800 kilograms of payload, and the maximum launching weight of the whole satellite can reach 5200 kilograms. It can be launched by launch vehicles such as Long March 3B, Ariane and Proton. The design life of the platform is 15 years.

Beidou navigation satellite:

"Beidou Navigation Test Satellite" (Beidou) was developed by China Association for Science and Technology, and the first generation satellite navigation and positioning system-"Beidou Navigation System" will be established by itself.

Beidou Navigation System is a regional navigation system that provides all-weather and all-weather satellite navigation information. After the system is completed, it will mainly provide navigation services for highway transportation, railway transportation, offshore operations and other fields, and will play a positive role in promoting China's national economic construction. The first successful launch of Beidou Navigation Test Satellite laid the foundation for the construction of Beidou Navigation System.

The launch of Beidou Navigation Test Satellite uses the Long March 3A carrier rocket. This launch is the 63rd flight of China Long March series launch vehicles.

Zhongxing 22:

"Zhongxing-22" is a practical geosynchronous communication satellite and the follow-up star of "Dongfanghong-3". The satellite, with a mass of 2.3 tons and a designed service life of 8 years, is mainly used for ground communication services and operated by China Communication Broadcasting Satellite Company.

It is understood that after the satellite enters the transfer orbit, it will be fixed above the equator at 98 degrees east longitude under the tracking control of the An Satellite Measurement and Control Center and the space ocean survey ship.

Fengyun 2:

FY-2 satellite is a cylinder with a diameter of 2.1.6m and a height of1.6m. The total height of the satellite including the antenna is 3. 1 m and it weighs about 600kg. The attitude of the satellite is spin-stable, and the spin speed is 100 1 rpm. This satellite is designed.

The satellite is equipped with multi-channel scanning radiometer and cloud image forwarding, which can obtain visible light cloud images, day and night infrared and water vapor cloud images. Broadcast and develop wide digital images, low-resolution cloud images and S-band weather maps: obtain observation data from meteorological, marine and hydrological data collection platforms; Collect space environmental monitoring data. The satellite works over the equator of east longitude105, and its position keeping accuracy is 0.5 from east to west and 0/from north to south.

Fengyun-2 satellite was jointly developed by China Association for Science and Technology and Shanghai Space Administration. CAST is responsible for satellite control, propulsion, forwarding, antenna, measurement and control and some structural subsystems. 1At 20: 00 on June 1997, Fengyun-2 satellite was launched by cz-3. Under the measurement and control management of satellite ground measurement and control station and Wangyuan No.2 survey ship, the satellite has completed the separation of satellite and arrow, satellite rotation and so on.

Fengyun-2 satellite inherited the spin stabilization mode of Dongfanghong-2 satellite and adopted some new technologies such as multi-channel scanning radiometer, three-channel microwave transmission and nutation control. The main performance indexes of this satellite have reached the level of similar geostationary meteorological satellites in the early 1990s. Fengyun-2 meteorological satellite is a combination of space technology, remote sensing technology, communication technology and computer technology. It provides directional coverage and continuous remote sensing of the distribution of the earth's surface and atmosphere, and has the advantages of strong real-time, high time resolution, objectivity and vividness.

Fengyun No.1:

FY- 1 is a series of polar-orbiting meteorological satellites in China. Three satellites, FY- 1A, 1B and 1C, were launched.

FY- 1A and 1B were launched in September 1988 and September 1990 respectively. They are experimental meteorological satellites. The remote sensors carried by these two satellites have good imaging performance, and the experimental data and operational experience obtained provide meaningful data for the development and management of subsequent satellites.

FY-/KOOC-0/C was launched on/KOOC-0/May, 1999/KOOC-0/0, and operated in a sun-synchronous polar orbit of 90/KOOC-0/km, with a design life of 3 years. The main remote sensor of the satellite is a visible-infrared scanner with very high resolution. The number of channels is increased from 5 FY- 1A/B to 10, and the resolution is 1 100 meters.

Remote sensing data obtained by satellites are mainly used for weather forecasting and environmental monitoring, such as vegetation, ice and snow cover, floods and forest fires.

Dongfanghong No.1:

On April 24th, 0970, at 2 1 35, the Dongfanghong-1 satellite (DFH- 1) was successfully launched at the Dongfeng Range in Jiuquan, Gansu Province, which opened a new era in China's space history and made China the fifth country in the world to independently develop and launch artificial earth satellites after the Soviet Union, the United States, France and Japan.

The satellite adopts spin stabilization mode. The electronic tone generator is the core part of the whole satellite, which repeatedly plays the first eight bars of the music "Dongfanghong" to the ground through the 20MHz short wave transmission system.

Dongfanghong No.2:

Dongfanghong-2 (DFH-2) was successfully launched for the first time on April 8, 1984. * * * Developed and launched three Dongfanghong-2 satellites. The development and launch of every three satellites took nearly 1970 years. The successful launch of "Dongfanghong II" started the history of satellite communication with our own communication satellite.

Dongfanghong No.2 A:

Dongfanghong-2 A is a modified satellite of Dongfanghong-2 satellite, and its pre-research work began at 1980.

The first Dongfanghong -2A satellite was successfully launched on1March 7th, 988. Soon after, the second and third satellites were successfully launched. They are fixed at 87.5, 1 10.5 and 98 respectively. The fourth star failed to enter the scheduled orbit due to the third stage failure of the launch vehicle.

Over the past few years, the three satellites have worked well, reaching the design and use targets, and played a great role in China's TV transmission, satellite communication and foreign broadcasting.

Dongfanghong-3 satellite:

Dongfanghong-3 satellite is a new generation communication satellite in China, which is mainly used for TV transmission, telephone, telegraph, fax, broadcasting and data transmission.

There are 24 C-band transponders on board, six of which are medium-power transponders. Other 18 channels are low-power repeaters. Service areas include: Chinese mainland, Hainan, Taiwan Province Province and offshore islands. Eirp≥37 dbw for medium power channel and 33.5 dbw for low power channel. During the shadow period, all transponders are working. The output power of the satellite at the end of its life is ≥ 1700W: the allowable payload mass of the satellite reaches 170kg.

The satellite works in the geostationary orbit, and its position accuracy is 0. 1 in the east-west and north-south directions. The antenna pointing error in pitch and roll directions is 0.65438 0.5, and the error in yaw direction is 0.5. The working life of the satellite is 8 years, and the single satellite reliability at the end of its life is 0.66.

Satellites can be docked with various launch vehicles (ZC-3A, Ariane -4, etc.). ), the satellite platform adopts the general platform of geostationary orbit satellite (basic type), which can be used for a variety of medium-sized applications.

Dongfanghong-3 satellite has the advanced level (medium capacity) of similar satellites in the world.

Shi Jian-1 satellite:

Shi Jian-1 satellite (SJ- 1) is a scientific exploration and technical test satellite. /kloc-0 was launched into orbit on March 3, 977, and the satellite's orbital life ended on May1/kloc-0. The ship's long-term telemetry system has been clearly sending telemetry information back to the ground.

Shijian-1 is a spin-stabilized satellite, and its successful launch took less than 10 months.

Resource-1 satellite:

ZY- 1 is the first transmission earth resource satellite in China. 1988, the governments of China and Brazil signed a protocol and decided to jointly develop China-Brazil Earth Resources Satellite (CBERS) on the basis of Resource-1 satellite.

Resources 1 are mainly used to monitor the change of land resources; Estimate forest stock and crop growth, quickly identify the estimated losses of floods and earthquakes, and put forward countermeasures; Provide dynamic information on coastal economic development, beach utilization, aquaculture and environmental pollution; At the same time, explore underground resources, so that they can be rationally developed and utilized. Resource-1 satellite weighs 1450 kg and has a life span of two years. The orbit is synchronized with the sun, with an altitude of 778 kilometers and an inclination of 98.5 degrees. The orbital period is 100.26min, and the regression period is 26 days. The local time of the downlink node is 1 1:20. The satellite is a cuboid with a single-wing solar panel. The satellite adopts three-axis stable attitude control mode and S-band and ultrashort wave measurement and control system.

The resource-1 satellite was successfully launched by the Long March 4B carrier rocket in1June+1April/October, 1999.

China-Pakistan Resources Satellite:

China-Pakistan Earth Resources Satellite (CBERS) was jointly developed by China and Pakistan on the basis of the original scheme of China Resources No.1, and it is stipulated that CBERS will be jointly used by the two countries after it is put into operation.

Resource-1 satellite is the first generation satellite to transmit earth resources in China. The three kinds of remote sensing cameras on board can observe the earth day and night, and the collected data are transmitted back to the earth ground receiving station by high-rate data transmission system, and processed into pictures needed by various users.

Because of its multi-spectral observation, wide range of earth observation and fast data collection, it is especially beneficial to the dynamic and rapid observation of surface information.

Because the satellite has the characteristics of multi-spectral observation, wide observation range of the earth, fast data acquisition and macroscopic intuition, it is especially beneficial to dynamically and quickly observe the earth's ground information.

The main uses of the satellite in China's national economy are: its image products can be used to monitor the changes of land resources and update the national utilization map every year; Calculate the cultivated land area, estimate the forest stock, crop growth, yield and grassland stock and their annual changes; Monitoring natural and man-made disasters; Quickly identify damages such as floods, earthquakes, forest fires and sandstorms, estimate losses and put forward countermeasures; Provide dynamic information on coastal economic development, beach utilization, aquaculture and environmental pollution; At the same time, explore underground resources, delineate resource areas such as gold, oil, coal and building materials, and supervise the rational development of resources.

Chang 'e-1 satellite:

Chang 'e 1 is the first lunar probe independently developed and launched by China. Chang 'e-1 lunar exploration satellite, a Chinese lunar exploration project, was developed by China Academy of Space Technology and named after Chang 'e, an ancient mythical figure in China. The Goddess Chang'e flying to the moon is an ancient myth circulating in China. Chang 'e-1 is mainly used to obtain three-dimensional images of the lunar surface, analyze the distribution characteristics of related material elements on the lunar surface, detect the thickness of lunar soil and detect the space environment of the earth and the moon. The whole "flying to the moon" process takes about 8-9 days. Chang 'e-1 will run in a circular polar orbit 200 kilometers from the surface of the moon. The working life of Chang 'e-1 is 1 year, and it is planned to fly around the moon for one year. Will not return to earth after the mission. With the successful launch of Chang 'e-1, China became the fifth country in the world to launch a lunar probe.

Tianlian-1 satellite:

Tianlian-1 satellite is the first data relay satellite launched by China, mainly developed by China Academy of Space Technology. It adopts the mature "Dongfanghong III" general platform and breaks through a number of key technologies. Its successful launch has filled the gap in the field of relay satellites in China.

Its task is to provide data relay and measurement and control services for satellites, spaceships and other spacecraft, which greatly improves the use efficiency and emergency capability of various satellites, enables data such as resource satellites and environmental satellites to be downloaded in real time, and wins more early warning time for dealing with major natural disasters. Therefore, it is called "satellite among satellites".

As we all know, GPS system is the national defense navigation satellite system of the United States, and it is also used for civil navigation. GLONASS in Russia, similar to GPS, consists of a space part, a ground monitoring part and a user receiver part, all of which are composed of 24 satellites with a height of about 20,000 kilometers. GPS is distributed on six orbital planes, each with four satellites, GLONASS is distributed on three orbital planes, and each with eight satellites. The distribution of satellites makes it possible to observe more than four satellites anywhere in the world at any time, thus obtaining high-precision three-dimensional positioning data. This provides a global navigation capability that is continuous in time. The positioning accuracy of GPS can reach 15m, and the speed measurement accuracy is 0.1m/s; GLONASS navigation and positioning accuracy is low, about 30- 100 meters, and speed measurement accuracy is 0. 15 meters per second. These two systems provide all-weather, continuous, real-time, high-precision three-dimensional position, three-dimensional speed and accurate time for planes, ships, tanks, ground vehicles, infantry, missiles and space shuttles all over the world, so they have extremely high military value and civil prospects.

Fengyun-3 satellite:

Fengyun-3 was launched from Taiyuan Satellite Launch Center on May 27th, 2008. It is the first new generation polar-orbiting meteorological satellite in China. It is equipped with three-dimensional sensors, which can monitor the earth's atmosphere and climate, and can make all-weather forecasts around the world. Fengyun-3 is equipped with visible infrared scanning radiometer, infrared spectrometer, microwave thermometer, microwave imager, etc. 10 and many other international advanced detection instruments. The detection performance is qualitatively improved compared with the first generation polar-orbiting meteorological satellite Fengyun-1, which only uses visible light as a means. It can carry out three-dimensional, all-weather, multi-spectral and quantitative detection on a global scale, obtain parameters such as surface, ocean and space environment, and realize medium-term numerical prediction.

Fengyun 3' s leap has four aspects:

First, from a single optical observation to the comprehensive detection of 10 advanced instruments, we can not only obtain cloud images, but also reproduce the temperature changes of the whole atmosphere from high to low at various heights through spectral chromatography.

The second is to solve the problem of cloud occlusion. When traditional optical detection encounters clouds, the detection effect is greatly reduced, while Fengyun-3 can clearly and accurately grasp the inside of clouds and the ground below them.

The third is the breakthrough of resolution and sensitivity. The width of a frame scanned by Fengyun-3 is as high as thousands of kilometers, and the ground resolution reaches the order of 100 meters on such a huge photo. The highest detection sensitivity of on-board instruments reaches 0. 1K, which means that satellites at an altitude of 807 kilometers above the ground can accurately feel the slight change of surface temperature of 0. 1℃.

Fourthly, the real-time performance of satellite data transmission is greatly improved. The satellite orbits the earth once every 10 1 minute, passing through the poles every time. Through the ground station near the North Pole leased from Sweden, the satellite can transmit data back to the ground at least once every 10 1 minute, which greatly improves the real-time performance of data transmission.