我們在(zai)給客(ke)戶(hu)介紹產品(pin)時，都(dou)會提(ti)到天線(xian)二(er)字。接觸(chu)過(guo)無線(xian)網橋(qiao)(qiao)的(de)朋友都(dou)會知道，無線(xian)網橋(qiao)(qiao)都(dou)是(shi)(shi)有(you)(you)天線(xian) ，只是(shi)(shi)分(fen)為內置(zhi)天線(xian)和(he)外(wai)置(zhi)天線(xian)。內置(zhi)的(de)由于看(kan)不到，常(chang)常(chang)誤(wu)以為沒有(you)(you)天線(xian)。很多客(ke)戶(hu)會問是(shi)(shi)帶(dai)天線(xian)的(de)好還(huan)是(shi)(shi)不帶(dai)天線(xian)的(de)好，今天，小編在(zai)這(zhe)里正式回(hui)復下，無論哪(na)一(yi)種無線(xian)網橋(qiao)(qiao)，都(dou)是(shi)(shi)有(you)(you)天線(xian)的(de)，只是(shi)(shi)內置(zhi)和(he)外(wai)置(zhi)的(de)區(qu)別(bie)。

　　無(wu)(wu)線(xian)(xian)(xian)(xian)網(wang)(wang)(wang)橋(qiao)信(xin)號發(fa)射(she)(she)原(yuan)理：發(fa)射(she)(she)端(duan)網(wang)(wang)(wang)橋(qiao)輸(shu)出(chu)的(de)(de)射(she)(she)頻信(xin)號功率(lv)通過饋線(xian)(xian)(xian)(xian)(電(dian)(dian)纜)輸(shu)送到天(tian)線(xian)(xian)(xian)(xian)，再由(you)(you)天(tian)線(xian)(xian)(xian)(xian)以電(dian)(dian)磁波形式輻射(she)(she)出(chu)去，當電(dian)(dian)磁波到達(da)接收(shou)(shou)地(di)點后，由(you)(you)天(tian)線(xian)(xian)(xian)(xian)接收(shou)(shou)下來，并通過饋線(xian)(xian)(xian)(xian)送到接收(shou)(shou)端(duan)網(wang)(wang)(wang)橋(qiao)。可知天(tian)線(xian)(xian)(xian)(xian)是(shi)無(wu)(wu)線(xian)(xian)(xian)(xian)網(wang)(wang)(wang)橋(qiao)信(xin)號的(de)(de)發(fa)射(she)(she)設備，沒(mei)有天(tian)線(xian)(xian)(xian)(xian)，無(wu)(wu)線(xian)(xian)(xian)(xian)網(wang)(wang)(wang)橋(qiao)的(de)(de)信(xin)號沒(mei)法發(fa)射(she)(she)出(chu)去，也(ye)就沒(mei)有無(wu)(wu)線(xian)(xian)(xian)(xian)電(dian)(dian)通信(xin)。也(ye)就是(shi)說，我(wo)們常說的(de)(de)無(wu)(wu)線(xian)(xian)(xian)(xian)網(wang)(wang)(wang)橋(qiao)傳輸(shu)實際(ji)是(shi)通過天(tian)線(xian)(xian)(xian)(xian)傳輸(shu)的(de)(de)。

　　而且天(tian)(tian)(tian)(tian)線(xian)(xian)的(de)(de)分(fen)類很多，根據不(bu)(bu)同(tong)(tong)(tong)頻率(lv)網橋，不(bu)(bu)同(tong)(tong)(tong)距離(li)，不(bu)(bu)同(tong)(tong)(tong)環境，不(bu)(bu)同(tong)(tong)(tong)場合使用不(bu)(bu)同(tong)(tong)(tong)的(de)(de)天(tian)(tian)(tian)(tian)線(xian)(xian)。按(an)安裝(zhuang)方式不(bu)(bu)同(tong)(tong)(tong)，有(you)內置天(tian)(tian)(tian)(tian)線(xian)(xian)和外(wai)置天(tian)(tian)(tian)(tian)線(xian)(xian)；按(an)方向的(de)(de)區分(fen)，有(you)定向天(tian)(tian)(tian)(tian)線(xian)(xian)和全(quan)向天(tian)(tian)(tian)(tian)線(xian)(xian)；按(an)頻率(lv)區分(fen)有(you)2.4G天(tian)(tian)(tian)(tian)線(xian)(xian)和5.8G天(tian)(tian)(tian)(tian)線(xian)(xian)；按(an)外(wai)形(xing)區分(fen)有(you)八木天(tian)(tian)(tian)(tian)線(xian)(xian)，平(ping)板天(tian)(tian)(tian)(tian)線(xian)(xian)，鍋(guo)狀天(tian)(tian)(tian)(tian)線(xian)(xian)……如此多的(de)(de)天(tian)(tian)(tian)(tian)線(xian)(xian)，選(xuan)擇(ze)會不(bu)(bu)會很困難(nan)？

　　一、內置天線(xian)和(he)外置天線(xian)

　　1，內置天線

　　內(nei)(nei)置(zhi)天(tian)線是(shi)指天(tian)線一(yi)體化(hua)無(wu)線網橋(qiao)，體積小，安裝方便，一(yi)般(ban)用于近距離無(wu)線傳輸系統(tong)中，一(yi)般(ban)10公里(li)內(nei)(nei)都可以使用內(nei)(nei)置(zhi)天(tian)線。

　　2，外置天線

　　外(wai)置天線(xian)(xian)一(yi)般較大，如果(guo)傳(chuan)(chuan)輸(shu)的(de)距(ju)離(li)(li)比(bi)較遠(yuan)，比(bi)如10公里以上，就建議采用高增益外(wai)置天線(xian)(xian)。外(wai)置天線(xian)(xian)的(de)遠(yuan)距(ju)離(li)(li)傳(chuan)(chuan)輸(shu)一(yi)般是點對點傳(chuan)(chuan)輸(shu)。因為傳(chuan)(chuan)輸(shu)距(ju)離(li)(li)遠(yuan)，角(jiao)度會相對比(bi)較小。全向天線(xian)(xian)除外(wai)。

　　二、定(ding)向(xiang)天線和全向(xiang)天線

　　1，定向天線

　　在(zai)水平方向圖(tu)上表現為(wei)一定角度(du)范圍(wei)輻射(she)，主要輻射(she)范圍(wei)象個倒立的不太完整的圓錐，一般應用(yong)(yong)于(yu)傳(chuan)(chuan)輸距離(li)遠、覆(fu)蓋范圍(wei)小(xiao)、目標密(mi)度(du)大(da)、頻(pin)率利用(yong)(yong)率高的環境。定向天(tian)線(xian)的信(xin)號只能向前面傳(chuan)(chuan)遞(di)。采用(yong)(yong)定向發射(she)天(tian)線(xian)的目的，是增(zeng)加(jia)輻射(she)功率的有效利用(yong)(yong)率，增(zeng)加(jia)保密(mi)性，增(zeng)加(jia)抗(kang)干(gan)擾能力。

　　2，全向天線

　　即在水平方向圖(tu)上表現為360°都均勻輻射，輻射范圍(wei)比(bi)較(jiao)象一個蘋(pin)果，具有無無方向性(xing)，一般應用在傳輸距離近(jin)、覆蓋(gai)范圍(wei)大的(de)環境中。全向天線的(de)信號向四面(mian)八方發射，價格便宜，增益比(bi)較(jiao)小，一般在12dBi以下。

　　三(san)，2.4G天線(xian)(xian)和5.8G天線(xian)(xian)

　　頻(pin)率(lv)的(de)(de)選擇(ze)非(fei)常簡單，就是(shi)無線網(wang)橋的(de)(de)頻(pin)率(lv)是(shi)多少是(shi)來選擇(ze)相應(ying)的(de)(de)天線。如果無線網(wang)橋是(shi)2.4G的(de)(de)，就選擇(ze)2.4G的(de)(de)天線；無線網(wang)橋是(shi)5.8G的(de)(de)，就選擇(ze)5.8G的(de)(de)天線。千萬不用(yong)將(jiang)2.4G的(de)(de)天線用(yong)在(zai)(zai)5.8G的(de)(de)網(wang)橋或者5.8G的(de)(de)天線用(yong)在(zai)(zai)2.4G的(de)(de)網(wang)橋中，會導致無法傳(chuan)輸信號。

　　看著文字(zi)覺得(de)天線有些復(fu)雜。其實很簡單的。只要(yao)把你的具體情況跟萊安工作人員說清(qing)楚，我們會(hui)幫你配置好。完全不用自己去思考選擇(ze)。