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weiter5494
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加入日期: Nov 2013
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MDIF是一個由已故華盛頓郵報主編所創立的非營利組織,旨在提倡不受干擾的無界新聞自由。

a non-profit corporation and investment fund that provides low-cost financing to independent news media in countries with a history of media oppression. It works with newspapers, radio stations, and TV companies in Africa, Asia, Latin America, the CIS, and the Balkans.

透過低利貸款給這些地區的新聞媒體,維持其穩定運作,迄今已貸出近1.3億鎂。

Outernet形式是一種倡議,意在創建一個不受審查的新聞、知識聯播網,是單向性的broadcasting ,接收端無法發射request。

The Outernet team claim that only 60% of the world's population currently have access to the wealth of knowledge that can be found on the Internet. This is because, despite a wide spread of Wi-FI devices across the globe, many countries are unable or unwilling to provide people with the infrastructure needed to access the web.

In actuality, the plan isn't to provide complete access to the web, but rather broadcast a selection of "high-quality" news and educational content to folks around planet. The communication would be one-way only at first—more like multichannel wireless programming.

Each satellite receives data streams from a network of ground stations and transmits that data in a continuous loop until new content is received. In order to serve the widest possible global audience, the entire constellation utilizes UDP-based multicasting over WiFi. Although still not common, WiFi multicasting is a proven technology, especially when the data requires only one hop to reach the recipient.

They'll be able to broadcast the Internet around the world. The group is hoping to raise tens of millions of dollars in donations to get the project on the road.

In September 2014 they will make a request to NASA to test their technology on the International Space Station.

By early 2015 they intend to begin manufacturing and launching their satellites.

And in June 2015 the company says they will begin broadcasting the Outernet from space.

由於並非商業應用,outernet並非採用成本高昂的大型特製衛星,而是類似開源精神的標準架構的nanosatellite(cubesat),要達到全球覆蓋率,估計需數數百上千顆(銥衛星系統是66顆)。而這種微型衛星,架構精簡,功能也比較侷限,但在政府研究機關跟學術單位已採用多年,也都是在簡易的特定應用上。

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What are Cubesats?

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NASA Ames Nanosatellite Launched Aboard Minotaur-1 Rocket

早期這一類的衛星通訊計畫,由於高昂衛星造價與接收終端功率的因素,最終無法成功。現有的衛星通訊僅只於偏遠惡劣的特殊應用場合。

2G時代的當年,由於基地台的數目有限,掀起一片衛星熱,企建覆蓋全球的衛星網,如Motorola的Iridium、Loral/Qualcomm的Globalstar、Bill Gates的Teledisc, 都以失敗收場。美國衛星電視大鱷DirecTV也搞過用小耳朵下傳,用數據機上傳的衛星寬頻,同樣慘淡。這些都2G時代的插曲,今時今日,手機寬頻來到LTE-A境界的mobile internet事實上已跟宣傳中的outernet是不同檔次的規格;再者,nanosatellite雖然造價較低,但發射成本跟維護成本與消費市場需求也難以匹配。與其期待它是一個創新的科技,毋寧是一種新的web應用模式,打造Internet的美國之音或自由之聲。


'Outernet' Wants to Free the Internet by Sending It to Space這篇文章有指出一些疑點,免费 Wi-Fi 覆盖全球:创始人们似乎根本不懂这事儿的困难一文提出更多的質疑,有空可以瞧瞧。
舊 2014-02-22, 12:27 AM #214
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