<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区
          chinadaily.com.cn
          left corner left corner
          China Daily Website

          Satellite navigation system launched

          Updated: 2011-12-28 07:30
          By Xin Dingding ( China Daily)

          Country joins elite club as Beidou goes into operation on trial basis

          BEIJING - China started to run its own satellite positioning system, Beidou, on Tuesday as the country climbed the global tech ladder and challenged the monopoly of the West.

          Beidou, or Big Dipper, the domestic version of the US Global Positioning System (GPS), started providing navigation, positioning and timing data on a pilot basis to China and the neighboring area for free on Tuesday, Ran Chengqi, director of the China Satellite Navigation Office, said.

          The system, with 10 orbiting satellites, covers an area from Australia in the south to Russia in the north. Signals can reach the Xinjiang Uygur autonomous region in the west and the Pacific Ocean in the east, Ran said.

          With six more satellites to be launched next year, the system will cover a wider area and eventually the entire globe by 2020 with a constellation of 35 satellites, he said.

          The accuracy of the positioning service will also improve as more satellites orbit.

          During the trial run Beidou can offer positioning to within 25 meters but when the system is officially launched next year accuracy will be enhanced to within 10 meters, he said.

          With the system operational China is the third member of an elite group, along with the US and Russia, to develop a satellite navigation system.

          The US spent 20 years and more than $20 billion on the GPS. Completed in 1994, the system has 24 navigation satellites and is widely used around the world.

          Beidou has its own unique features, Ran said.

          "It not only tells users where they are and what time it is but also allows users to tell others the information through short messages," Ran said, adding that this feature is being considered by other systems.

          Russia's Glonass system achieved a 24-satellite constellation in 1996 but succumbed to funding problems.

          The rebuilding of the Glonass system is almost finished and Russian media reported that the system resumed service earlier this month.

          The European Union and the European Space Agency are building the Galileo satellite navigation system. Japan and India also intend to build independent regional navigation systems.

          Previous Page 1 2 Next Page

           
           
          ...
          ...
          ...
          主站蜘蛛池模板: 日本高清熟妇老熟妇| 国产草草影院ccyycom| 加勒比无码av中文字幕| 亚洲国模精品一区二区| 欧美丰满熟妇xxxx性| 2021国产v亚洲v天堂无码| 国产激情一区二区三区午夜| 国产旡码高清一区二区三区| 亚洲Av综合日韩精品久久久| 国产精品日韩中文字幕熟女| 国产伦码精品一区二区| 视频一区二区三区四区久久| 第一精品福利导福航| 夜爽8888视频在线观看| 亚洲午夜片| 亚洲Av综合日韩精品久久久| 18禁视频一区二区三区| 久热综合在线亚洲精品| 99热国产成人最新精品| 日韩av在线一卡二卡三卡| 中文字幕精品久久久久人妻红杏1| 亚洲乱色一区二区三区丝袜| 国产97人人超碰CAO蜜芽PROM| 野外做受又硬又粗又大视频| 把女人弄爽大黄A大片片| 国内偷自第一区二区三区| 中文字幕亚洲国产精品| 欧美亚洲另类 丝袜综合网| 国内熟妇人妻色在线视频| 亚洲自偷自拍熟女另类| 99精品国产兔费观看久久99| 久久免费偷拍视频有没有| 成人午夜看黄在线尤物成人| 91精品91久久久久久| 亚洲图片综合图区20p| 一道本AV免费不卡播放| 国产亚洲综合一区二区三区| 精品精品亚洲高清a毛片| 亚洲码和欧洲码一二三四| 无卡国产精品| 亚洲人精品亚洲人成在线|