什麼東西看不見摸不着，但是卻很重要！
文藝青年--愛情！
普通青年--空氣！
我————WIFI！
Who doesn't love free WiFi?Although we use it often, we rarely think about how it works. If you've everwondered, here's how...
誰不喜歡免費的WIFI，雖然我們經常在使用它，但是人們卻很少去想象他如何工作（本苦逼WIFI工程師除外），如果你也曾經想知道過，下面就是WIFI的樣紙！
Wifi is an energy field that is transmitted aswaves. The waves have a certain height, distance between them and travel at acertain speed. The distance between wifi waves is shorter than that of radiowaves and longer than that of microwaves, giving wifi a unique transmissionband that can't be interrupted by other signals. This image shows an idealizedwifi data transmitted over a band that is divided into different sub-channels,which are shown in red, yellow, green and other colors.
WIFI是種帶有能量的電磁波，但是不同於普通電磁波的是WIFI是種經過調製的具有固定的振幅，載波與傳輸速率。WIFI傳輸距離要比FM/AM等廣播波距離短，比微波距離要長點（此處指的是3GHz以後的微波，編者純粹以理論來撰寫），（FCC）賦予了WIFI專門的工作頻段，所以WIFI能夠儘量避免被其他信號干擾（編者寫的是can't,不對）。下圖是一個理想情況下的一個頻段內的WIFI通過不同子信道傳輸（還是應該翻譯成一個信道內的各種不同的子載波，編者寫的東西太文藝了，本青年完全讀不明白），被顯示爲，巴黎紅，東京黃，倫敦綠和腹黑色。
The wifi pulses are shown here as multicoloredspheres radiating out from the source, near the right of the image. Wifitransmitters are basically an antenna equipped with a transmission protocolthat splits the frequency band into several segments, referred to as channels.Data can be transmitted over each channel or in order to send and receivegreater quantities of data at faster rates. Although color represents its ownunique, visible segment of the electromagnetic spectrum, we use red, orange,yellow and other colors to show the invisible wifi channels that make up theoverall wifi signal. Wifi fields are usually spherical (like the one here) orellipsoidal and extend about 20-30 meters, assuming a typical off the shelfwifi box.
WIFI電磁波是從圖中右邊的中心點射出來瞭然後顯示爲多彩多殼的蛋蛋。WIFI信號在一個頻段內被分割成一個個信道，然後經過天線進行傳輸（一個天線傳一個信道），每一個信道都能承載數據，爲了傳輸更多的數據，WIFI可以用高速率幀來進行數據傳輸。我們呈現了一個WIFI的整體形狀，這個蛋蛋由用紅成黃等色來顏色來裝扮不可見的不同信道WIFI的電磁波的信道（上文應該寫的就是信道了）。WIFI信號被從一個發射器裏射出來樣子通常是個球或者是個橢球，並且會擴展20-30m。
Wifi waves travel through space as rapid, dataencoded pulses or waves. A freeze frame of these pulses would show that thepulses are about 6 inches apart (as shown by the lightly colored bandstraveling through space in this image). Wifi routers are basically antenna thatcan send data over multiple frequencies all at the same time. These multiplefrequencies are shown as blue, green, yellow, and red colors that pervade thespace around the mall. The data from these multiple frequencies swirls aroundin space as shown here, but can be translated using a common tag systemunderstood by wireless devices.
WIFI信號通過空間快速的傳輸着數據，一個靜止的無線幀將會呈現無線傳輸時的樣紙，一個無線脈衝波之間大概間隔6英尺的距離（375px，2.4GHz的波長明顯是5英尺300px），無線路由器長着2個小揪揪天線，傳輸數據時可以複用多個信道，這些信道被顯示成藍綠黃和紅瀰漫在了林蔭道中。下圖就是無線啵啵的樣子，這些信號都能被WIFI聯盟認證的設備來接受。
Wifi routers or antenna can be attached to trees,buildings, lamp posts and otherstructures. A typical outdoor router can project its signal 300 feet or morefrom its location. Objects such as trees can obstruct the signal such thatit has to be augmented by multiple wifi routers placed in differentpositions. Multiple routers can create a field that extends all the wayacross Washington DC's National Mall as shown here. This image shows datainstantaneously transmitted over different frequencies from a wifi antenna asblue, indigo and yellow fields.
WIFI 陸遊器或天線能夠被裝在樹上，大樓上，馬路邊的燈竿上或者其他一切能裝的且有人的地方，一個室外的無線AP能夠把它的信號射到300碼（274m）之外，但是有一些物體比如樹葉會吸收WIFI信號，所以需要一些增強型的WIFI AP被放在不同的地方好讓大家都能上網。高級的AP能夠掛在白宮外面，發射信號讓奧黑能坐在小樹林旁的板凳上拿着手機發twitter。下圖是白宮上方的彩虹。
Wifi routers affixed to buildings, lampposts and other object create a circular data field around them. Theseantenna have an omnidirectional signal that extends equally in all directions,shown as the circular bands. Wifi broadcasts at a frequency between radioand microwaves, meaning that the waves or pulses are about six inches apart, asshown by the colored, circular bands.
WIFI AP被安裝在屋頂，燈杆和其他尖尖的上方，信號如同水波一樣一圈圈圍繞着他們，這些天線都是全向天線。沒配圖。WIFI的信號是2.4GHz或者5GHz，波長6英寸。
The illustrations were produced with thehelp of M. Browning Vogel. She has a Ph.D. in Astrobiology, worked atNASA Ames for five years, and now teaches science at the Universitylevel.
這些圖像都是在M.Browning Vogel的幫助下構架出來的，她是個天體太空學家，曾在NASA工作了好多年，現在在大學教書。
Please email [email protected] for high resolution images.
發郵件到[email protected]以瞭解更多WIFI知識。