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China's Space Program, News & Views

This is a discussion on China's Space Program, News & Views within the Strategic Defense forums, part of the China Defense & Military category; Originally Posted by Quickie Only 5 of the 35 Beidou satellites are in GEO. The rest are in MEO. Coverage ...

  1. #1681
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    Re: China's Space Program, News & Views

    Quote Originally Posted by Quickie View Post
    Only 5 of the 35 Beidou satellites are in GEO. The rest are in MEO. Coverage is limited to the pacific area because they've sent up only about half of the network of satellites. AFAIK, Global coverage is expected to be in 2020.
    There are also 5 sats in IGSO.
    Last edited by escobar; 10-26-2012 at 11:43 AM.
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    Re: China's Space Program, News & Views

    Vid showing BD-2 sats ...

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  3. #1683
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    Re: China's Space Program, News & Views

    Some details on BD-2 system: link

    - G6 is equiped with 4 chinese rubidium atomic clocks with an accuracy of 1 nanosecond.
    - The first sats are equipped with two chinese clocks and two american clocks (accuracy of 9-10 second)
    - The development of the Chinese atomic clock dates back to 1995, in 2000 the first laboratory prototype came out. Between 2003 and 2005, all sub-components of the prototype were certified. In 2007 the industrial prototype finished its development and has begun to equip the BD-2 sats.
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    Re: China's Space Program, News & Views

    The YG-16 (A/B/C) sats have arrived at JSLC on Sep 25. Tests will last approximately 2 months before the launch scheduled in late Nov.
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    Re: China's Space Program, News & Views

    The largest radio telescope in China will be commissioned in Shanghai tomorrow after two months of intensive testing. With a 65m diameter and a weight about 2600t It will be the fourth most powerful radio telescope in the world and is able to observe celestial objects 100 million light years from earth.



    Last edited by escobar; 10-28-2012 at 08:51 PM.
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    Re: China's Space Program, News & Views

    The Five-hundred-meter Aperture Spherical Radio Telescope Project and its Early Science Opportunities: pdf
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    Re: China's Space Program, News & Views

    China unveils large radio telescope in Shanghai

    A massive radio telescope for use in space observation was unveiled Sunday at the foot of Sheshan Mountain in Shanghai.

    The telescope will be used to track and collect data from satellites and space probes.

    The newly-built radio telescope can pick up eight different frequency bands and also track Earth satellites, lunar exploration satellites and deep space probes,
    said Hong Xiaoyu, head of the Shanghai Astronomical Observatory.

    "We hope that the new radio telescope will go into operation earlier so that we can use it to observe the unmanned lunar probe Chang'e-2," said Wu Weiren, chief designer of the lunar orbiter project.

    The telescope will be used for Very Long Baseline Interferometry (VLBI), a type of astronomical interferometry used in radio astronomy, as it can collect accurate data and increase its angular resolution during astronomical observation.

    ...
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    Re: China's Space Program, News & Views

    The engine in the circle is said to be a full-scale model of the YF660 and the third one from left is YF100.

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    Re: China's Space Program, News & Views

    5th manned space trip for next year

    China's fifth manned space mission will lift off next year, Yang Liwei, China's first "taikonaut" - China's terms for its astronauts - and deputy director of the country's manned space program has confirmed.

    The exact date of the launch will be decided after a full assessment of previous missions by spacecraft Shenzhou-8 and Shenzhou-9.

    Yang said the Shenzhou-10 manned spacecraft will carry three taikonauts into space, and that the crew will include veterans and perhaps women. "It is possible that female astronauts will be on board," he added. The candidates will be decided early next year.

    Next year's space mission mainly aims to consolidate and improve docking techniques, conduct more scientific experiments and solve problems discovered in the previous missions
    , said Yang.

    "One success doesn't mean success every time," he told a news conference in Shanghai. "We would like to have more practice and improve the quality," Yang explained.

    Yang was in town for the opening of an aerospace and aviation exhibition marking the 20-year anniversary of the launch of China's manned space program.

    At the event, Yang also revealed that the Shenzhou-10 mission will adjust the working schedule and routine of taikonauts, laying the foundation for building a space station.


    Technical breakthroughs

    "Once established, the space station will provide a national-level platform for scientific research in outer space," Yang added. "So the next mission will also focus on technical breakthroughs in environmental control and life support systems."

    After the Shenzhou-10 space mission, China is scheduled to launch the Tiangong-2 space lab module to research supply transport by cargo spaceships, another milestone for China's space program.

    "Space travel won't be a problem for China in the future," Yang said.

    The aviation exhibition, featuring 150 photographs, documents and other objects, is being held at Qian Xuesen Library and Museum of Shanghai Jiao Tong University. One of the highlights is the re-entry capsule of the Shenzhou-4 spaceship.
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    Re: China's Space Program, News & Views

    commissioning

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    Re: China's Space Program, News & Views

    More details on this radio telescope:

    - It is the third in the world to adopt active surface technique and has excellent surface accuracy.
    - has a 130-meter long track, to support horizontal movement.
    - The width of the track is accurate to within just point five millimeters and the telescope itself has over 1100 precision mechanisms.
    - An official from China Electronics Technology Group Corporation says the completion of the radio telescope in Shanghai means that China’s industrial technology has reached the most advanced level in the world.
    - Fan Youshan, Leader of China Electronics Technology Group Corp., said, "Large diameter radio telescopes are a hi-tech product. It has extremely high requirements for engineering mechanism design, machinery processing, industrial control, supercomputing, information analysis, and installation and construction."
    - China also plans to build an antenna system for a 110m diameter radio telescope in the Xinjiang
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    Re: China's Space Program, News & Views

    Quote Originally Posted by Hendrik_2000 View Post
    China tests advanced technologies on Shijian-9 A/B satellites

    ...

    For example, Shijian-9B satellite’s core control computer is “SoC2008″ chip, independently developed by No. 502 Institute of under China Academy of Space Technology(CAST), has completely independent intellectual property rights. This indicates that China has made a breakthrough and master the SoC system level design, anti-radiation enhance design, fault-tolerant design, highly reliable real-time operating system design and other key technologies to occupy leading position in the world.

    A system on a chip or system on chip (SoC or SOC) is an integrated circuit (IC) that integrates all components of a computer or other electronic system into a single chip. It may contain digital, analog, mixed-signal, and often radio-frequency functions—all on a single chip substrate. A typical application is in the area of embedded systems. SoC technology is the inevitable outcome of the development of microelectronic technology to an advanced stage.

    With SoC technology, Chinese aerospace platform is no longer in a situation of continued requirement on foreign chips, but to base on domestic design, production and technological level, and to determine the more reasonable aerospace electronics technology, system architecture, and performance specifications, and make the progressive realization of the high-end chip production’s localization. SoC technology is the key strategic technology to realize core components independence.

    SoC2008 is a high-performance SOC chip oriented for aerospace electronic systems, with low-power and anti-radiation enhancement. It can meet the application needs of all kinds of spaceborne electronic systems. SoC2008 overall performance is equal with products launched in Europe in 2010, reached the international advanced level in the same period. SoC2008 has been applied in CAST100 series small satellite platform’s control computer, long-life star sensor control computer, satellite landing central control unit, space station robotic arm subsystem controller and cargo spacecraft GNC subsystems guidance.
    A new official article reveals more details about the “SoC2008″ chip: link

    - According to the SJ-9 sats orbits data, "everything is normal!" which means SoC2008 successfully passed last verification.
    - Soc reduce spacecraft volume saving valuable space
    - SpaceOS2 a second generation real-time multi-tasking OS is run on SoC2008 (SpaceOS1 is the first version used on TG-1)
    - SpaceOS2 overall performance reached international advanced level and is equal to UT699 launched in Europe in 2010
    - Second-generation SoC chip and multi-core high-performance SoC chip are already in development
    - The first quad-core SoC to be used on the lunar and Beidou-2 following program will be available in 2013.
    - Has also broad application in high-speed rail, nuclear power and marine tech



    Last edited by escobar; 10-28-2012 at 08:09 PM.

  13. #1693
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    Re: Chinese Satellites

    Quote Originally Posted by escobar View Post
    China to build high-resolution earth observing system

    Starting from 2013, China will develop and launch a series of new-model earth observing satellites and put them into use. It plans to complete the construction of a high-resolution earth observing system by around 2020.

    The project of constructing a high-resolution earth observing system, approved and started in May of 2010, is one of the 16 major special projects set by the “Outline of National Program for Medium and Long-term Scientific and Technological Development (2006-2020).”

    In this project, a high-resolution earth observing system based on satellites, airships of stratosphere and aircrafts will be designed and constructed as a whole, making China have the ability of observing the entire surface of the earth in all weathers and around-the-clock.

    Currently, the research and experiment tasks of various systems are being carried out smoothly.

    According to sources, after the system is complete, it will be able to provide information services and decision supports for many areas of China, including the modern agriculture, disaster prevention and relief, resources, environment and public security. It will also meet many requirements from China's economic construction and social development.
    We know more about this new series of sats. They are called Gao Fen (high-resolution). It seems that 14 sats are planned with launch times from 2013 to 2020. The first one GF-1 will be launched next year. His design is said to be similar to VRSS.

    Expected launch schedule:

    2013: GF-1 (2m res pan-chromatic camera/8m res. multi-spectral camera/16m res. wide-angle multi-spectral camera)
    2013: GF-2 (1m res pan-chromatic camera/4m res. multi-spectral camera)
    2015: GF-3 (1m res C-band SAR)
    2015: GF-4 (50m res fixed-point camera in GEO)
    2015: GF-5 (visible light-near infrared hyper-spectral camera/full-frequency spectrometer/atmospheric greenhouse gas monitor/atmospheric trace gas absorption spectrometer atmospheric aerosol multi-angle photometer/atmospheric environment very-high resolution infrared radiation detector)
    2016:GF-6 (2m res pan-chromatic camera/8m res multi-spectral camera/16m res wide-angle multi-spectral camera)
    2018:GF-7 (hyper-spectral, sterographic and cartography cameras)
    The GF-4 sat is very noteworthy.
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    Re: China's Space Program, News & Views

    China has mastered the key technologies (grain integrity, nozzle thermal structure, engine ignition) of large solid rocket motors: link
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    Re: China's Space Program, News & Views

    I just find china has been working on a regional positioning system called CAPS (Chinese Area Positioning System) since 2002. its architecture is very interesting: pdf-1, pdf-2, link

    The space segment consists of some Geostationary Earth Orbit (GEO) satellites and 2∼3 Inclined Geo-Synchronous Orbit (IGSO) satellites. Only a few satellites are needed to provide good area coverage and hence it is an ideal space segment for a regional navigation system. CAPS is also different from all the other navigation satellite systems in that the navigation messages are generated on the ground and uploaded to the communication satellites, with the satellites acting only as transponders.

    A time transfer mode is used to transmit navigation signals, so no high-precision atomic clocks are required onboard the satellites; all of the transferred navigation signals are generated by the same atomic clock at the master control station on the ground. The determination of the clock offset is completely independent of the determination of satellite orbit, so the error of the clock offset has no impact on orbit determination. Therefore, a very high precision of satellite orbits, better than 4·2 cm (1 drms) can be obtained by the stations under regional distribution.

    A prospective view of CAPS has concluded it to be a seamless, high accuracy, large capacity navigation and communication system which can be achieved by expanding it world wide and enhancing it with LEO satellites and mobile base stations. Hence, this system is a potential candidate for the next generation of radio navigation after GPS.
    Last edited by escobar; 10-30-2012 at 08:17 PM.
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