光纖的測試技術介紹

1、光纖的測試技術介紹技術創(chuàng)新，變革未來目錄光纖與銅纜的對比光纖基礎知識光纖的選用影響衰減的因素光纖測試設備Fiber Optic Advantages?光纖與銅纜的對比項目光纖（FIBER）銅纜（COPPER）線纜價格低較高抗電磁/射頻（EMI/RFI）干擾能力不會被干擾NEXT、FEXT等連接器抗電磁/射頻（EMI/RFI）干擾能力不存在總要被考慮接地回路不存在總要被考慮損耗低相對高帶寬高正在提高溫度穩(wěn)定性可能是個問題可能是個問題重量非常輕可能是個問題易于安裝熔接困難比較容易安裝及維修工具的價格高低網卡價格光/電/光轉換部件昂貴路由器便宜放大器價格光/電/光轉換部件昂貴測試工具價格昂貴的OTD

2、R認證測試要求損耗、傳輸延遲和長度單根或成對測試測試項目較多，可同時雙向多線對測試光纖基礎知識電磁譜Frequency (Hz)UV可見光(750 - 380 nm)X-RaysIRAMRadioWavelength (m)101210810141010101610181UHFVHF10610-310-9常用的光波長(660, 850, 1300,1310, &1550 nm)光纖基礎知識波長的選擇FirstWindowSecondWindowThirdWindow波長 (nm)8001200160008Loss(dB/km)4多模(MD)工作于 850 nm 和 1300 nm單模(SM)工

3、作于 1310 nm 和 1550 nm多模與單模光纖MULTIMODE FIBER Huge Volume Short Distance 2 kmSINGLE MODE FIBER Huge Volume Long Distance From 2km to 100kmCoreCladdingCoatingMultimode FiberPowered by LEDs and VCSELs at 850nm and 1300nmLow cost electronics Usually Has ORANGE JacketingShort Distances (2km)Great for: Loca

4、l Area Networks,CCTV, Campus Area Networks, Offices and ManufacturingInexpensive for Short Distances, Expensive for Long DistanceCore Diameters: 50um, 62.5um & 100umSinglemode FiberPowered by Lasers at 1310nm,1550nm and 1625nmHigh Power Long Distance 2km to 100kmGreat for: Wide Area Networks, Metro.

5、 Area Networks, CATV, Utilities & TelcosInexpensive for Long Distance Compared to Copper, Expensive for Short DistanceCore Diameter: 9umUsually has YELLOW Jacketing光纜結構表皮 (材料 PVC)抗拉材料緩沖填充物核Fiber Optic Connectors光纜的接合Mechanical 機械式Quick 快速Little specialized equipment required 一般不需特殊設備New techniques a

6、nd splice connectors have improved the loss per splice (some 0.1 dB) 新技術和連接器改善了接合的損耗Good for emergency field repairs, low volumes 應急，小數(shù)量Fusion 熔結Requires special, expensive equipment 需要特殊設備Very low loss (can be 0.05 dB) 極低的損耗The only method for long-haul links 長距離鏈路的唯一方法激光產品的級別Class I 無危險Class IIa 觀

7、看時間小于1000秒則安全Class II 長期觀看有危險Class IIIa 直接觀看有嚴重危害Class IIIb 直接輻射對眼睛和皮膚有嚴重傷害Class IV 直接觀看或散射對眼睛和皮膚有嚴重傷害LASERWARNINGTIA/EIA 568B StandardCable電纜Maximum fiber loss per km (at 850 nm) 3.75 dBMaximum fiber loss per km (at 1300 nm) 1.5 dBMaximum fiber loss per km (at 1310 nm) 1.0 dBMaximum fiber loss per

8、km (at 1550 nm)1.0 dBConnections (Duplex SC or ST)連接器Maximum adapter loss: 0.75 dBMaximum splice loss: 0.3 dBLink Lengths (backbone)鏈路長度Segment HC-IC IC-MC62.5/125 Multimode 500 m 1500 m50/125 Multimode (under proposal) 8/125 Singlemode 500 m 2500 m 光鏈路損耗的原因光纜的材料純度材料密度的變化光纜的彎曲程度宏觀彎曲(安裝問題)微觀彎曲(產品制造問題

9、)光纜接合以及連接的耦合損耗不潔或連接質量不良Bare fiberThis makes yousay bad words.密度改變Density Change氣泡Bubble雜質ImpurityMicrobend裂紋Macrobend造成衰減的原因1.光纖本身的缺陷耦合損耗Coupling LossesArea mismatchSpacing lossAxis misalignmentAngular misalignmentLosses at splices and connectors, including test equipment connectors:光纖的測試光功率損耗插入損耗長度傳輸時延故障定位FIBERTEK采用F