繼十多年前手機開始在非洲普及後，這塊大陸近來更成為網路業的全新市場，
網路公司爭相在此進行試驗計畫，設置以電視空白頻譜傳送的無線網路，
預計未來將會大幅改變非洲民眾生活中的各個層面，不過此時，仍有技術及資金等現實挑戰等著克服。
在南非開普敦的艾爾伍德中學，即使是在牆上裝入金屬網，也無法阻止竊賊拔走那些讓學生能連上網路的銅纜線。
但艾爾伍德中學的學生受惠於另一項科技：利用未使用到的電視頻譜，也就是俗稱的「空白頻譜」，所傳送的免費無線網路。
這項服務由一間谷歌的合作夥伴所提供，是一項廣大試驗的其中一部分。微軟也在南非其他地方進行一樣的試驗。兩家企業爭相研究這個也許終將為整個非洲帶來便宜寬頻網路的科技。
非洲是世上最後一塊大多還未開發的網路市場。根據國際電信聯盟，非洲數十億人口中，僅有16％民眾能取得網路，是亞洲網路普及率的一半。
由於普遍缺乏西方國家網路所使用的陸上通訊線路，大部分能上網的非洲民眾都是透過手機上網，而手機普及則讓非洲2010年時僅2％的寬頻使用率，在2013年成長到11％。
然而，由於手機電信公司不願在偏鄉地區建造昂貴的電視天線及電視網絡，非洲數億人能上網的機會仍相當渺茫。
微軟谷歌 爭相開拓市場
谷歌和微軟正在開拓這個廣大的新市場，不僅要提供那些未被網路覆蓋的鄉村地區「空白頻譜」，更要藉此解決都會區中，部分地區因過度擁擠且建築林立而導致的電話訊號太差的問題。
非洲的電視頻道相當少，辛巴威就只有一個電視台；而這對發展這項技術來說相當理想，因為可取得的空白頻譜很多。
微軟則在肯亞、坦尚尼亞及南非進行試驗計畫，為的是在日後推出商業計畫；谷歌則贊助南非全境的學校試用版，艾爾伍德中學就是其中之一。
這兩間公司爭相為新客戶開發更便宜的上網管道，很明顯是出於一樣的動機；不過同時，非洲各政府也有許多開發網路的誘因。
世界銀行研究顯示，寬頻普及率每增加10％，就能讓年度經濟成長增加額外的1.4％。
新興科技 訊號強成本低
為了讓各頻道間不互相干擾，電視網絡會在頻道間保留空白的間隔，而這項科技就用這些「空白頻譜」來傳送及接收無線數據訊號。
目前電視無線電波的傳遞範圍達半徑10公里，使之成為偏遠鄉村理想的上網工具。
比起手機訊號，電視無線電波能更輕易的穿透牆壁，成本也更低。谷歌開普敦空白頻譜試驗計畫的計畫經理哈特表示，打造一座空白頻譜的電視天線，僅需要一般電信基地的1／10費用。
當地的網路服務供應商也對開發這項科技很有助益。在坦尚尼亞，微軟和UhuruOne公司合作，提供網路給三蘭港大學的學生。這項計畫將於一月拓展至4所大學，嘉惠超過7萬2千名學生，且每月寬頻費用只要5美元（約新台幣150元）。
在肯亞，Indigo電訊公司及美國國際發展署正與微軟合作，要提供無線寬頻網路給數間鄉村學校、一間健康診所及裂谷省偏遠地區的政府辦公室。
目前Indigo提供學校的是免費網路，不過未來計畫要對周圍社群收取每月1.5美元（約新台幣45元）的上網費。計畫提供了基礎設備如光纖電纜、電視天線和無線電設備，微軟則提供軟體和應用程式。
因為網路 生活簡單太多
政府大多相當歡迎這項科技，不過部分官員持保留態度，擔心這些信號是否會影響或干擾到保留給軍隊、緊急救護及航空交通管制的頻寬。
不過，微軟非洲倡議計畫的通訊組長庫柏森說道：「此刻，我們有充足證據顯示，空白頻譜的無線電波可與其他目前已獲得許可者共存，不會有任何干擾的風險。」
場景回到開普敦，那些參加試驗計畫的學校希望一切進展順利。他們急切的緊抓住他們最新、最快、也更可靠的網路。
「我們不介意為此付費，因為這在我們這裡確實能運作。」開拓者高中的科技組長郝普特說道。這是開普敦試驗計畫中較富裕的一所學校。「我們已經逐漸習慣這項良好的服務了。」他說。
艾爾伍德中學一間擁擠的電腦教室內，10年級的雅可布正在休息時間做作業；他總結到：「這讓生活簡單太多了。」（路透）
（圖說）南非開普敦的艾爾伍德中學內，學生正在使用電腦，圖攝於2013年11月7日。（圖文／路透）
At Cape Town's Elswood Secondary School, even the metal grills welded into its walls did not deter burglars from ripping out the copper cables that delivered Internet to the students.
But Elswood's pupils were saved by alternative technology - free wireless connection via unused parts of the TV spectrum（1） known as white space.
It's being provided by a consortium led by Google as part of a wider trial. Elsewhere in the country Microsoft is operating similar pilots. Both are racing to fine tune a technology that could ultimately bring cheap broadband to the entire continent.
Africa is the world's last major untapped market for Internet access. Only 16 percent of its billion people use the Internet - half the penetration rate（2） of Asia, according to the International Telecommunication Union.
Most Africans who can access the Internet do so via mobile phones because few have the landlines（3） that have been the means of connecting in Western countries. This has pushed broadband usage to 11 percent this year from just 2 percent in 2010.
But mobile phone companies are reluctant to build costly masts（4） and networks in remote rural areas - meaning hundreds of millions of Africans have little prospect of ever going online.
Google and Microsoft are chasing this massive new market, aiming to provide white space Internet access to rural swathes with no coverage and in megacities where overcrowding and built up areas can mean frustratingly poor phone reception.
Africa's thinly populated airwaves - Zimbabwe, for instance, has only one TV station - make it ideal for this technology because of the abundance of available spectrum.
Microsoft is running pilot schemes（5） in Kenya, Tanzania and South Africa with the aim of launching commercial projects thereafter. Google is sponsoring trials in schools, including Elswood, across South Africa.
While for both firms the logic of developing cheaper ways to access new customers is clear, the incentive for governments is also compelling.
World Bank research shows that a 10 percent increase in broadband penetration can result in an extra 1.4 percentage points of annual economic growth.
Television networks leave idle gaps between channels in order to protect themselves from interference from other networks. The technology uses these "white spaces" to transmit and receive wireless data signals.
The adapted TV radio waves can travel up to a 10-kilometre radius, making them ideal for connecting off-grid villages.
They penetrate walls better than mobile signals. And they're cheap to provide: building a white spaces mast costs a tenth of the amount needed for a normal telecoms base station, said Arno Hart, project manager for the Cape Town white spaces trial being funded by Google.
Local Internet service providers are helping: In Tanzania Microsoft has partnered with UhuruOne to provide connection to students at the University of Dar es Salaam. In January the project will be expanded to four universities, giving more than 72,000 students broadband access for $5 a month.
In Kenya, Indigo Telecom and the United States Agency for International Development are working with Microsoft to provide wireless broadband to rural schools, a health clinic and government office in remote areas of the Rift Valley province.
Indigo is currently providing free Internet to schools but plans to charge those living in the surrounding community $1.50 per month for connectivity in future. It has provided the infrastructure - fibre, masts and radios - while Microsoft supplies the software and applications.
Governments have largely welcomed the technology though some officials have expressed reservations about whether it could affect or cross into bandwidth reserved for the military, emergency services and air traffic control.
But Whitney Cubbison, communications director for Microsoft's Africa initiatives, said:"At this point, we feel there is ample proof that white space radios can coexist with incumbent licensees without any risk of interference."
Back in Cape Town, schools participating in the trials hope everything works out. They are keen to hang on to their new, faster and more reliant Internet.
"We don't mind paying for it because it works for us," said Paul Haupt, head of IT at The Settlers High School, a more affluent school in the Cape Town trial. "We've gotten used to a good service."
Tyler Jacobs, an Elswood 10th grader working on his homework during a break in a packed computer room, summed it up: "It makes life so much easier."Reuters
關鍵字詞
1.spectrum（n.）頻譜
2.penetration rate（n.）普及率
3.landline（n.）陸上通訊線路
4.mast（n.）天線
5.pilot scheme（n.）試驗計畫
