光纤的测试技术介绍

1、光纤的测试技术介绍技术创新，变革未来目录光纤与铜缆的对比光纤基础知识光纤的选用影响衰减的因素光纤测试设备Fiber Optic Advantages?光纤与铜缆的对比项目光纤（FIBER）铜缆（COPPER）线缆价格低较高抗电磁/射频（EMI/RFI）干扰能力不会被干扰NEXT、FEXT等连接器抗电磁/射频（EMI/RFI）干扰能力不存在总要被考虑接地回路不存在总要被考虑损耗低相对高带宽高正在提高温度稳定性可能是个问题可能是个问题重量非常轻可能是个问题易于安装熔接困难比较容易安装及维修工具的价格高低网卡价格光/电/光转换部件昂贵路由器便宜放大器价格光/电/光转换部件昂贵测试工具价格昂贵的OTD

2、R认证测试要求损耗、传输延迟和长度单根或成对测试测试项目较多，可同时双向多线对测试光纤基础知识电磁谱Frequency (Hz)UV可见光(750 - 380 nm)X-RaysIRAMRadioWavelength (m)101210810141010101610181UHFVHF10610-310-9常用的光波长(660, 850, 1300,1310, &1550 nm)光纤基础知识波长的选择FirstWindowSecondWindowThirdWindow波长 (nm)8001200160008Loss(dB/km)4多模(MD)工作于 850 nm 和 1300 nm单模(SM)工

3、作于 1310 nm 和 1550 nm多模与单模光纤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光缆结构表皮 (材料 PVC)抗拉材料缓冲填充物核Fiber Optic Connectors光缆的接合Mechanical 机械式Quick 快速Little specialized equipment required 一般不需特殊设备New techniques a

6、nd splice connectors have improved the loss per splice (some 0.1 dB) 新技术和连接器改善了接合的损耗Good for emergency field repairs, low volumes 应急，小数量Fusion 熔结Requires special, expensive equipment 需要特殊设备Very low loss (can be 0.05 dB) 极低的损耗The only method for long-haul links 长距离链路的唯一方法激光产品的级别Class I 无危险Class IIa 观

7、看时间小于1000秒则安全Class II 长期观看有危险Class IIIa 直接观看有严重危害Class IIIb 直接辐射对眼睛和皮肤有严重伤害Class IV 直接观看或散射对眼睛和皮肤有严重伤害LASERWARNINGTIA/EIA 568B StandardCable电缆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)连接器Maximum adapter loss: 0.75 dBMaximum splice loss: 0.3 dBLink Lengths (backbone)链路长度Segment HC-IC IC-MC62.5/125 Multimode 500 m 1500 m50/125 Multimode (under proposal) 8/125 Singlemode 500 m 2500 m 光链路损耗的原因光缆的材料纯度材料密度的变化光缆的弯曲程度宏观弯曲(安装问题)微观弯曲(产品制造问题

9、)光缆接合以及连接的耦合损耗不洁或连接质量不良Bare fiberThis makes yousay bad words.密度改变Density Change气泡Bubble杂质ImpurityMicrobend裂纹Macrobend造成衰减的原因1.光纤本身的缺陷耦合损耗Coupling LossesArea mismatchSpacing lossAxis misalignmentAngular misalignmentLosses at splices and connectors, including test equipment connectors:光纤的测试光功率损耗插入损耗长度传输时延故障定位FIBERTEK采用F