一、光纖故障測試儀是什么
光纖故障測試儀主要用于檢測(ce)(ce)光纖(xian)的故障(zhang)位置和性質。常見(jian)的兩類測(ce)(ce)試儀(yi)是(shi)光纖(xian)OTDR測(ce)(ce)試儀(yi)(英文全稱是(shi)Optical Time Domain Reflectometer)和光纖(xian)OLTS測(ce)(ce)試儀(yi)(英文全稱是(shi)Optical Loss Test Set)。
光(guang)纖(xian)OTDR(Optical Time Domain Reflectometer)可以檢測(ce)(ce)出(chu)光(guang)纖(xian)斷開距離測(ce)(ce)試點的距離,以及由(you)菲涅爾(Fresnel)反(fan)射和(he)瑞利(Rayleigh)散射回到(dao)的數(shu)據信(xin)號。然而,要通過OTDR來精準地測(ce)(ce)量端到(dao)端的耗損是有(you)難度的,因(yin)為在實(shi)際操作中,它(ta)會遇到(dao)測(ce)(ce)量盲(mang)區(qu),如事(shi)件和(he)衰(shuai)減系數(shu)盲(mang)區(qu)。
光纖(xian)OLTS(Optical Loss Test Set),也稱為光源(yuan)和功率(lv)(lv)計(ji)(ji)機器設備,它可以(yi)發(fa)送光源(yuan)檢(jian)測(ce)光信號(hao)(hao),然后通(tong)過被測(ce)鏈路(lu)進入(ru)光功率(lv)(lv)計(ji)(ji)以(yi)計(ji)(ji)算衰(shuai)減系(xi)數。OLTS能夠檢(jian)測(ce)的(de)指標包(bao)括鏈路(lu)的(de)總(zong)體衰(shuai)減系(xi)數和鏈接的(de)長度(du)。這種(zhong)設備的(de)精(jing)度(du)非常高,能夠在(zai)另(ling)一端B端檢(jian)驗并(bing)測(ce)量該數據(ju)信號(hao)(hao)的(de)功率(lv)(lv)等(deng)級。
總結來說(shuo),光纖(xian)故障測試儀是用于精(jing)確診斷(duan)光纖(xian)傳(chuan)輸系統(tong)問(wen)題的精(jing)密(mi)儀器,它們(men)可以幫助(zhu)技(ji)術(shu)人員(yuan)定位和解決問(wen)題,確保通信系統(tong)的正常運行。
二、光纖測試儀有哪些類型
常用光纖測試儀有:光功率計、穩(wen)定光源、光萬用表、光時域反射(she)儀(yi)(OTDR)和光故障定位儀(yi)。
1、光功率計
用(yong)于測量(liang)絕對(dui)(dui)光(guang)(guang)(guang)(guang)(guang)(guang)功(gong)(gong)(gong)(gong)率(lv)(lv)或(huo)(huo)通(tong)過一(yi)段光(guang)(guang)(guang)(guang)(guang)(guang)纖(xian)的(de)光(guang)(guang)(guang)(guang)(guang)(guang)功(gong)(gong)(gong)(gong)率(lv)(lv)相(xiang)對(dui)(dui)損(sun)耗(hao)。在(zai)光(guang)(guang)(guang)(guang)(guang)(guang)纖(xian)系(xi)統中(zhong),測量(liang)光(guang)(guang)(guang)(guang)(guang)(guang)功(gong)(gong)(gong)(gong)率(lv)(lv)是(shi)最基本的(de)。非(fei)常(chang)(chang)像電子(zi)學中(zhong)的(de)萬用(yong)表,在(zai)光(guang)(guang)(guang)(guang)(guang)(guang)纖(xian)測量(liang)中(zhong),光(guang)(guang)(guang)(guang)(guang)(guang)功(gong)(gong)(gong)(gong)率(lv)(lv)計(ji)是(shi)重負荷常(chang)(chang)用(yong)表,光(guang)(guang)(guang)(guang)(guang)(guang)纖(xian)技(ji)術(shu)人員(yuan)應(ying)該人手一(yi)個。通(tong)過測量(liang)發射端(duan)機或(huo)(huo)光(guang)(guang)(guang)(guang)(guang)(guang)網絡(luo)的(de)絕對(dui)(dui)功(gong)(gong)(gong)(gong)率(lv)(lv),一(yi)臺光(guang)(guang)(guang)(guang)(guang)(guang)功(gong)(gong)(gong)(gong)率(lv)(lv)計(ji)就能(neng)夠評價光(guang)(guang)(guang)(guang)(guang)(guang)端(duan)設(she)備(bei)的(de)性(xing)能(neng)。用(yong)光(guang)(guang)(guang)(guang)(guang)(guang)功(gong)(gong)(gong)(gong)率(lv)(lv)計(ji)與(yu)穩定光(guang)(guang)(guang)(guang)(guang)(guang)源組(zu)合使(shi)用(yong),則(ze)能(neng)夠測量(liang)連(lian)接損(sun)耗(hao)、檢(jian)驗連(lian)續性(xing),并(bing)幫助(zhu)評估光(guang)(guang)(guang)(guang)(guang)(guang)纖(xian)鏈路傳輸質量(liang)。
2、穩定光源
對光系(xi)統(tong)發射(she)已知(zhi)功率和波(bo)長(chang)的(de)光。穩定(ding)光源(yuan)與光功率計結(jie)合在一起,可(ke)(ke)以(yi)測(ce)量(liang)光纖系(xi)統(tong)的(de)光損耗(hao)(hao)(hao)。對現成的(de)光纖系(xi)統(tong),通(tong)常(chang)也可(ke)(ke)把系(xi)統(tong)的(de)發射(she)端(duan)機當作(zuo)穩定(ding)光源(yuan)。如果端(duan)機無法工作(zuo)或(huo)沒有端(duan)機,則需要(yao)(yao)單獨的(de)穩定(ding)光源(yuan)。穩定(ding)光源(yuan)的(de)波(bo)長(chang)應與系(xi)統(tong)端(duan)機的(de)波(bo)長(chang)盡可(ke)(ke)能(neng)一致。在系(xi)統(tong)安裝完畢后,經常(chang)需要(yao)(yao)測(ce)量(liang)端(duan)到端(duan)損耗(hao)(hao)(hao),以(yi)便確定(ding)連(lian)(lian)接(jie)損耗(hao)(hao)(hao)是否(fou)滿(man)足設計要(yao)(yao)求,如:測(ce)量(liang)連(lian)(lian)接(jie)器、接(jie)續(xu)點的(de)損耗(hao)(hao)(hao)以(yi)及光纖本(ben)體損耗(hao)(hao)(hao)。
3、光萬用表
用來測量光(guang)纖鏈路的光(guang)功率損耗。有(you)以(yi)下兩種光(guang)萬(wan)用表:
(1)由獨立(li)的光(guang)功率計(ji)和穩定光(guang)源組(zu)成。
(2)光功率(lv)計和穩定光源結合為(wei)一體的集成測試系統。
4、光時域反射儀(OTDR)及故障定位儀
(Fault Locator):表現為光(guang)(guang)纖損耗與距離的(de)(de)(de)(de)函(han)數。借助于OTDR,技術(shu)人(ren)員能夠看到整個系(xi)統(tong)輪廓,識別并(bing)測(ce)量光(guang)(guang)纖的(de)(de)(de)(de)跨(kua)度、接(jie)續點和(he)連接(jie)頭。在診斷(duan)光(guang)(guang)纖故(gu)障的(de)(de)(de)(de)儀(yi)表中,OTDR是(shi)最經(jing)典(dian)的(de)(de)(de)(de),也(ye)是(shi)最昂貴的(de)(de)(de)(de)儀(yi)表。與光(guang)(guang)功率計和(he)光(guang)(guang)萬用表的(de)(de)(de)(de)兩(liang)端測(ce)試不同,OTDR僅通過光(guang)(guang)纖的(de)(de)(de)(de)一端就(jiu)可測(ce)得光(guang)(guang)纖損耗。OTDR軌跡線給出系(xi)統(tong)衰減(jian)值的(de)(de)(de)(de)位(wei)置和(he)大小(xiao),如:任何連接(jie)器、接(jie)續點、光(guang)(guang)纖異(yi)形、或光(guang)(guang)纖斷(duan)點的(de)(de)(de)(de)位(wei)置及其損耗大小(xiao)。
故障(zhang)定位儀(yi)大(da)多是手持式儀(yi)器,適用(yong)于(yu)多模和(he)單模光纖系(xi)統。利用(yong)OTDR(光時域反射儀(yi)) 技術,用(yong)于(yu)對(dui)光纖故障(zhang)的點(dian)定位,測(ce)試距離(li)(li)大(da)多在20公(gong)里以內。儀(yi)器直接以數字顯示(shi)至故障(zhang)點(dian)的距離(li)(li)。