Optical network design

Optical system design generally follow these steps: 

1 First, the design is to be clear what kind of network, the status of how and why to use fiber. 
2 is based on the actual situation to select the appropriate fiber optic network equipment, fiber optic cable, patch cords and connecting with other items.Should be chosen to be used as a basis, then based on performance, price, service, place of origin and brand to determine. 
3 according to customer requirements and network types to determine the line of route, and draw the wiring diagram. 
4 When you need a longer route accounting system attenuation margin, accounting according to the following formula: 
Launched optical power attenuation margin = - Receiver Sensitivity - Line attenuation - connecting attenuation (dB) attenuation = cable length in which the line × unit attenuation; unit attenuation and fiber quality of a great relationship, usually single-mode for the 0.4 ~ 0.5dB/km; Multi-mode is 2 ~ 4dB/km. 
Attenuation, including splice connector to connect attenuation attenuation, splice attenuation and welding tools and the quality of personnel, generally melt is 0.01 ~ 0.3dB / point; cold fusion 0.1 ~ 0.3dB / point; connector attenuation and has a lot to the quality of joints, typically 1dB / point. System attenuation margin is generally less than 4dB. 
5 accounting failed, as the case may be to modify the design, then accounting.This may sometimes be repeated several times.