For lasers with tightly controlled wavelengths, approximately how far apart are the centers of adjacent wavelengths when 100 GHz spacing is used in a DWDM system?（）

单项选择题If the power is 0 dBm, what is the power in mW?（）

A.0mW
B.1mW
C.10mW
D.1.5mW

单项选择题Which device creates an OEO conversion?（）

A. amplifier
B. attenuator
C. regenerator
D. light emitter
E. optical switch
F. optical receiver
G. fiber-optic cable

单项选择题Given the formula: (Fiber Attenuation * Km) + (Splice Attenuation * # of Splices) + (Connector Attenuation * # of Connectors) + (Optical Fiber or OADM) + Buffer(Fiber aging)) With regard to SONET SDH optical calculations, what will the given formula provide?（）

A. fiber loss
B. OSNR level
C. post amplification
D. index of reflection
E. index of refraction
F. power post amplification budget

多项选择题What three in combination are factors that can cause four-wave mixing in fiber-optic cables? （）(Choose three.)

A. low optical power
B. high optical power
C. few optical channels
D. many optical channels
E. low chromatic dispersion
F. high chromatic dispersion
G. too much power differential in the optical channels

单项选择题Why are the 1300 nm and 1550 nm regions of the fiber spectrum primarily used for optical communications?（）

A. They are both regions of lowest loss.
B. They are both regions of low reflections.
C. They are both regions of low index of refraction.
D. They are both regions of low chromatic dispersion.
E. They are both regions of low Polarization Mode Dispersion (PMD).