Testing Parameters in Optical Network
Following are the testing parameters used in optical network.Trans optical power
•Receive optical power
•OSNR
•Dispersion (Read about dispersion here)
•Wavelength
•Wavelength deviation
•Fiber loss (Read about Fiber loss here)
•Connector loss
•Splicing loss
Optical Power Meter (OPM)
•Power meters are calibrated at the typical wavelengths used in fiber optics, 850, 1300 and 1550 nm.
•Some meter uses Auto wavelengths Recognition feature.
Optical Light Source(OLS)
•It should be compatible with the type of fiber in use (singlemode or multimode with the proper core diameter) and the wavelength.
•Sources may be either LED's or LASERS.
•Sometimes optical power meters are combined with an Optical Light Source (OLS) or Visual Fault Locator (VFL).
OTDR
•OTDR functions by injecting a series of optical pulses into the fiber under test, using LASER.
•It requires access to only one end of the fiber.
Fiber Trace at OTDR
Optical Spectrum Analyzer (OSA)
•Optical signal monitoring on live channels.
•Able to analyze
–Optical Power
–Optical wavelength
–OSNR of each wavelength
–Spectral width of optical source
Visual Fault Locator
•Visual Fault Locator is used to inject the visible light to visually trace fiber.
•It covers the range where OTDRs are not useful.
•This is used for buffered fiber and even jacketed single fiber cable if the jacket is not opaque to the visible light.