由于在(zai)(zai)(zai)戶(hu)(hu)(hu)外(wai)、室內等(deng)區(qu)域，無線(xian)(xian)對(dui)(dui)(dui)(dui)(dui)講系(xi)統(tong)的(de)(de)信(xin)(xin)(xin)(xin)號(hao)強度較弱，而且(qie)采用(yong)(yong)頻(pin)率調制(zhi)技術（如 MHZ、 NMR、 BSI等(deng)）產生的(de)(de)信(xin)(xin)(xin)(xin)號(hao)傳輸時(shi)延(yan)大，傳輸距離遠。因(yin)此(ci)有(you)線(xian)(xian)對(dui)(dui)(dui)(dui)(dui)講系(xi)統(tong)不(bu)(bu)適合在(zai)(zai)(zai)戶(hu)(hu)(hu)外(wai)環(huan)境使(shi)用(yong)(yong)，特別(bie)是(shi)在(zai)(zai)(zai)冬(dong)天及(ji)低風速(su)季(ji)節(jie)使(shi)用(yong)(yong)。雖然無線(xian)(xian)對(dui)(dui)(dui)(dui)(dui)講系(xi)統(tong)也(ye)有(you)著(zhu)不(bu)(bu)錯的(de)(de)效(xiao)果(guo)。但由于系(xi)統(tong)工作(zuo)時(shi)會有(you)一定的(de)(de)干(gan)擾，使(shi)對(dui)(dui)(dui)(dui)(dui)講效(xiao)果(guo)下(xia)降，另外(wai)在(zai)(zai)(zai)信(xin)(xin)(xin)(xin)號(hao)較弱時(shi)對(dui)(dui)(dui)(dui)(dui)用(yong)(yong)戶(hu)(hu)(hu)語(yu)音(yin)產生了(le)影(ying)響。特別(bie)是(shi)在(zai)(zai)(zai)人員復雜(za)、通信(xin)(xin)(xin)(xin)距離較短(duan)或需(xu)要(yao)較長(chang)時(shi)間(jian)使(shi)用(yong)(yong)時(shi)。因(yin)此(ci)，更需(xu)要(yao)有(you)一個可(ke)靠(kao)的(de)(de)無線(xian)(xian)對(dui)(dui)(dui)(dui)(dui)講系(xi)統(tong)提供與有(you)線(xian)(xian)對(dui)(dui)(dui)(dui)(dui)講系(xi)統(tong)一樣的(de)(de)語(yu)音(yin)信(xin)(xin)(xin)(xin)息與控制(zhi)。無線(xian)(xian)對(dui)(dui)(dui)(dui)(dui)講系(xi)統(tong)具有(you)很高的(de)(de)靈活性，它能(neng)夠滿足現(xian)場(chang)中(zhong)所有(you)環(huan)境使(shi)用(yong)(yong)需(xu)求并能(neng)隨(sui)時(shi)切換（如在(zai)(zai)(zai)野外(wai)、戶(hu)(hu)(hu)外(wai)電話等(deng)),用(yong)(yong)戶(hu)(hu)(hu)可(ke)以在(zai)(zai)(zai)任何地點使(shi)用(yong)(yong)、隨(sui)時(shi)、隨(sui)地進行(xing)通訊(xun)。使(shi)用(yong)(yong)方(fang)便(bian)、節(jie)省(sheng)成本、節(jie)約(yue)費用(yong)(yong)。下(xia)面我們來了(le)解一下(xia)無線(xian)(xian)對(dui)(dui)(dui)(dui)(dui)講系(xi)統(tong)它主要(yao)是(shi)什么(me)優(you)點？

1.性(xing)能穩定，可靠性(xing)高

在(zai)(zai)相同無(wu)(wu)(wu)線(xian)(xian)(xian)傳輸(shu)距離(li)下，無(wu)(wu)(wu)線(xian)(xian)(xian)傳輸(shu)信(xin)號(hao)(hao)更(geng)穩(wen)(wen)定(ding)(ding)(ding)由于(yu)使(shi)用了功率放(fang)大(da)器(qi)來對(dui)無(wu)(wu)(wu)線(xian)(xian)(xian)信(xin)號(hao)(hao)進行壓(ya)縮(suo)和放(fang)大(da)，使(shi)無(wu)(wu)(wu)線(xian)(xian)(xian)信(xin)號(hao)(hao)更(geng)加穩(wen)(wen)定(ding)(ding)(ding)可(ke)(ke)靠。無(wu)(wu)(wu)線(xian)(xian)(xian)信(xin)號(hao)(hao)在(zai)(zai)弱電磁環境下也能(neng)保(bao)持(chi)較好(hao)的(de)(de)(de)性(xing)能(neng)。無(wu)(wu)(wu)線(xian)(xian)(xian)對(dui)講(jiang)(jiang)系(xi)統具有(you)發(fa)射(she)功率小、抗(kang)(kang)千擾(rao)(rao)能(neng)力(li)(li)強(與(yu)有(you)線(xian)(xian)(xian)對(dui)講(jiang)(jiang)系(xi)統比(bi)較)和抗(kang)(kang)電磁干擾(rao)(rao)能(neng)力(li)(li)強(與(yu)有(you)線(xian)(xian)(xian)對(dui)講(jiang)(jiang)系(xi)統比(bi)較)的(de)(de)(de)特(te)點(dian)。無(wu)(wu)(wu)線(xian)(xian)(xian)對(dui)講(jiang)(jiang)系(xi)統發(fa)射(she)信(xin)號(hao)(hao)在(zai)(zai)發(fa)射(she)前和發(fa)射(she)后均(jun)能(neng)保(bao)持(chi)良好(hao)的(de)(de)(de)性(xing)能(neng)，使(shi)用過程中，發(fa)射(she)信(xin)號(hao)(hao)與(yu)接收信(xin)號(hao)(hao)完全不受任何千擾(rao)(rao)，可(ke)(ke)保(bao)持(chi)很(hen)好(hao)的(de)(de)(de)穩(wen)(wen)定(ding)(ding)(ding)性(xing)，具有(you)良好(hao)的(de)(de)(de)抗(kang)(kang)千擾(rao)(rao)性(xing)和抗(kang)(kang)低頻干擾(rao)(rao)能(neng)力(li)(li)，即使(shi)在(zai)(zai)惡劣的(de)(de)(de)環境下也能(neng)保(bao)持(chi)較好(hao)的(de)(de)(de)性(xing)能(neng)。因此無(wu)(wu)(wu)線(xian)(xian)(xian)系(xi)統有(you)較高的(de)(de)(de)可(ke)(ke)靠性(xing)。

2.功耗小、不受天(tian)氣(qi)、濕度的影(ying)響

無線(xian)對(dui)(dui)講(jiang)系統(tong)在不同的環(huan)境(jing)中(zhong)，無線(xian)通信(xin)設(she)備和有線(xian)通信(xin)設(she)備一樣(yang)都要進行電(dian)(dian)能的消耗(hao)。當環(huan)境(jing)溫度(du)(du)在-40°C以(yi)下時(shi)(shi)(shi)，無線(xian)通信(xin)設(she)備需要每(mei)天(tian)工作(zuo)8小時(shi)(shi)(shi)左(zuo)右(you);當環(huan)境(jing)溫度(du)(du)為-20°C時(shi)(shi)(shi)，每(mei)天(tian)工作(zuo)8小時(shi)(shi)(shi)左(zuo)右(you);當環(huan)境(jing)溫度(du)(du)為-30°C時(shi)(shi)(shi)，每(mei)天(tian)工作(zuo)4小時(shi)(shi)(shi)左(zuo)右(you)。目前市場上(shang)常(chang)見的無線(xian)對(dui)(dui)講(jiang)系統(tong)有兩種(zhong)(zhong)(zhong)電(dian)(dian)源輸(shu)入方式(shi)(shi)，一種(zhong)(zhong)(zhong)是(shi)電(dian)(dian)源輸(shu)入，另(ling)一種(zhong)(zhong)(zhong)是(shi)電(dian)(dian)源輸(shu)出(chu)。從這兩種(zhong)(zhong)(zhong)方式(shi)(shi)對(dui)(dui)系統(tong)的功(gong)(gong)耗(hao)來看，電(dian)(dian)源輸(shu)入方式(shi)(shi)的功(gong)(gong)耗(hao)更大一些，但(dan)是(shi)功(gong)(gong)耗(hao)很(hen)小。并且(qie)設(she)備的工作(zuo)環(huan)境(jing)不同，對(dui)(dui)電(dian)(dian)池的需求量也不同，所(suo)以(yi)功(gong)(gong)耗(hao)也不同。

3信號不受干擾

 在(zai)(zai)(zai)一(yi)些有干(gan)擾(rao)(rao)(rao)的(de)(de)地方，例如野(ye)外、機場、工(gong)廠等，一(yi)般(ban)采用(yong)(yong)分(fen)(fen)(fen)頻(pin)方式。分(fen)(fen)(fen)頻(pin)方式的(de)(de)抗干(gan)擾(rao)(rao)(rao)能(neng)(neng)力(li)不(bu)強(qiang)，其抗干(gan)擾(rao)(rao)(rao)能(neng)(neng)力(li)主(zhu)要(yao)取決于(yu)射(she)頻(pin)功(gong)率的(de)(de)大小(xiao)。分(fen)(fen)(fen)頻(pin)技(ji)術的(de)(de)功(gong)率一(yi)般(ban)是50dB在(zai)(zai)(zai)50dB左右時(shi)，其抗干(gan)擾(rao)(rao)(rao)能(neng)(neng)力(li)強(qiang)。但由(you)于(yu)分(fen)(fen)(fen)頻(pin)的(de)(de)干(gan)擾(rao)(rao)(rao)與(yu)噪聲(sheng)(主(zhu)要(yao)是周(zhou)邊噪聲(sheng))具有很(hen)強(qiang)的(de)(de)互(hu)通性，當分(fen)(fen)(fen)頻(pin)發(fa)射(she)的(de)(de)信(xin)(xin)號(hao)(hao)(hao)超過50dB時(shi)，其抗千擾(rao)(rao)(rao)能(neng)(neng)力(li)就會減弱。另外，在(zai)(zai)(zai)一(yi)些有噪音的(de)(de)環境中使(shi)用(yong)(yong)分(fen)(fen)(fen)頻(pin)技(ji)術，會使(shi)分(fen)(fen)(fen)頻(pin)信(xin)(xin)號(hao)(hao)(hao)無法到達發(fa)射(she)端的(de)(de)接(jie)(jie)收(shou)(shou)機或(huo)者造成發(fa)射(she)端信(xin)(xin)號(hao)(hao)(hao)與(yu)接(jie)(jie)收(shou)(shou)端信(xin)(xin)號(hao)(hao)(hao)的(de)(de)糟合而(er)造成分(fen)(fen)(fen)頻(pin)或(huo)干(gan)擾(rao)(rao)(rao)(例如在(zai)(zai)(zai)使(shi)用(yong)(yong)室外電話時(shi)) 。而(er)采用(yong)(yong)分(fen)(fen)(fen)頻(pin)技(ji)術的(de)(de)無線對(dui)講系(xi)統(tong)由(you)于(yu)發(fa)射(she)功(gong)率小(xiao)，分(fen)(fen)(fen)頻(pin)后(hou)的(de)(de)信(xin)(xin)號(hao)(hao)(hao)強(qiang)度比有線對(dui)講系(xi)統(tong)高(gao)很(hen)多(在(zai)(zai)(zai)實(shi)(shi)際(ji)使(shi)用(yong)(yong)中分(fen)(fen)(fen)頻(pin)設備一(yi)般(ban)可以將系(xi)統(tong)信(xin)(xin)號(hao)(hao)(hao)分(fen)(fen)(fen)頻(pin)到50dB以上),信(xin)(xin)號(hao)(hao)(hao)不(bu)受干(gan)擾(rao)(rao)(rao)。如果(guo)采用(yong)(yong)分(fen)(fen)(fen)頻(pin)技(ji)術，需要(yao)在(zai)(zai)(zai)較(jiao)大的(de)(de)回波功(gong)率下才能(neng)(neng)實(shi)(shi)現(xian)信(xin)(xin)號(hao)(hao)(hao)的(de)(de)分(fen)(fen)(fen)頻(pin)工(gong)作(如分(fen)(fen)(fen)頻(pin)器發(fa)射(she)信(xin)(xin)號(hao)(hao)(hao)與(yu)接(jie)(jie)收(shou)(shou)信(xin)(xin)號(hao)(hao)(hao)重疊時(shi)產生的(de)(de)千擾(rao)(rao)(rao))和發(fa)送(song)信(xin)(xin)號(hao)(hao)(hao)強(qiang)度降低(di)(同頻(pin)帶內(nei)的(de)(de)兩只(zhi)天線對(dui)同一(yi)信(xin)(xin)道傳輸的(de)(de)信(xin)(xin)號(hao)(hao)(hao)強(qiang)度基本(ben)一(yi)致);如果(guo)采用(yong)(yong)混響(xiang)技(ji)術，則可以實(shi)(shi)現(xian)對(dui)無線信(xin)(xin)號(hao)(hao)(hao)干(gan)擾(rao)(rao)(rao)的(de)(de)抑制或(huo)降低(di)。