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飛機(jī)上能玩手機(jī)?

2020-08-20 12:54
時代英語·高二 2020年4期
關(guān)鍵詞:廣播系統(tǒng)前提條件基站

雖然說現(xiàn)在乘坐飛機(jī)時可以將手機(jī)調(diào)成飛行模式,但在飛行期間使用手機(jī)也有諸多限制。那么,我們以后有可能在飛機(jī)上上網(wǎng)、打電話嗎?這么做又是否會給飛行帶來危險因素呢?

Every time we get on a plane, were asked to either turn off our phones or change them to flight mode—its for security reasons.

But according to The Conversation website, having to turn our phones off on a plane is “a service issue, not a safety one”.

When we speak on our phones in the air, they can cause interference to the aircrafts radios. Pilots can hear this interference in their headphones. “Its the same noise youll be familiar with, if you put your mobile too close to a speaker,” the Mirror noted. “It is not safety critical, but is annoying for sure.” Though speaking on a phone during a flight isnt dangerous, from the viewpoint of service, it isnt still a good idea.

When we make or receive a call on the ground, we connect to a cell tower that deals with all calls within an 80-kilometer radius. As we move from place to place we are “handed on” to different cell towers.

As US scientist Sven Bilen explains, for this system to work, there are “built-in” expectations: There shouldnt be too many “handoffs”; people shouldnt be traveling faster than car speeds and phone users should be close to the ground.

If we were to make phone calls while we flew, however, none of these expectations would be met. And even worse, our cellphones would stop working.

But now things are beginning to change. We still cant speak during a flight, but we can use other phone functions. For example, Airbus A330 of Emirates Airlines has in-flight Wi-Fi to make passengers send and receive short messages in the air. In the future, as Bilen points out, it may be possible for air travelers to make and receive calls freely.

The breakthrough could be “pico cells”, which are small cell towers on the plane itself. There would no longer be connections made between phones and the ground and therefore there would be no danger of disruption to phone service.

One day, perhaps, we will be chatting in the air as much as we chat on the ground.

每當(dāng)我們坐飛機(jī)的時候,都會被要求關(guān)閉手機(jī)或者將手機(jī)調(diào)成飛行模式——這是出于安全考慮。

但據(jù)“對話”網(wǎng)站報道,在飛機(jī)上關(guān)閉手機(jī)是“出于服務(wù)原因,而非安全原因”。

當(dāng)我們在飛機(jī)上用手機(jī)通話時,手機(jī)會對飛機(jī)的廣播系統(tǒng)造成干擾。飛行員們會在耳機(jī)中聽到這種干擾聲?!斑@種干擾聲大家也很熟悉,就是手機(jī)離話筒太近時發(fā)出的聲音?!薄剁R報》指出,“這種聲音不會影響安全,但的確很煩人?!北M管在飛行期間打電話并不危險,但從服務(wù)的角度考慮,這么做依然不妥。

在地面打電話時,我們會連接到一個負(fù)責(zé)方圓80公里以內(nèi)所有通信的手機(jī)基站。在移動的過程中,會有不同的基站來負(fù)責(zé)我們的通信。

正如美國科學(xué)家斯文·比倫所解釋的那樣,這套系統(tǒng)運(yùn)作時有一些“內(nèi)置”的前提條件:信號轉(zhuǎn)移的次數(shù)不應(yīng)太多;人們移動的速度不應(yīng)超過車速,并且使用手機(jī)時應(yīng)靠近地面。

然而,如果我們在飛行途中打電話卻無法滿足上述任何一個前提條件。更糟糕的是,我們的手機(jī)會無法使用。

但如今,情況正發(fā)生著改變。盡管我們還不能在飛行期間打電話,但卻可以使用手機(jī)的其他功能。比如,阿聯(lián)酋航空公司的空客A330機(jī)型都配備了無線網(wǎng)絡(luò),使乘客們能在空中收發(fā)短信。正如比倫指出的那樣,未來飛機(jī)上的乘客們或許還能隨意撥打、接聽電話。

這項(xiàng)突破技術(shù)便是“微微基站”,這是種設(shè)置在飛機(jī)上的小型手機(jī)基站。這樣一來,手機(jī)就無須連接到地面的基站,手機(jī)通信也不會被破壞了。

或許某一天,我們能在空中煲電話粥,就如同在地面一樣。

Word Study

interference /'?nt?'f??r?ns/ n. (無線電訊號的)干擾;干預(yù)

I wanted to do the thing on my own without outside interference or help.

disruption /d?s'r?p??n/ n. 妨礙;擾亂;中斷

The plan was designed to ensure disruption to business was kept to a minimum.

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