DWDM is an innovation that enables multiple optical carriers to travel in parallel in a fiber. DWDM devices combine the output from several optical transmitters for transmission across a single fiber. At the receiving end, another DWDM device separates the combined optical signals and passes each channel to an optical receiver. Only one optical fiber […]
Optical Amplifier
Basic Knowledge About EDFA
In optical communication network, signals travel through fibers for very large distances without significant attenuation. However, when the signals need to transmit several hundreds of kilometers, it becomes necessary to amplify the signals during transit. EDFA (erbium doped fiber amplifier), commercialized in the early 1990’s, became a key enabling technology for optical communication networks, and […]
Dual Stage EDFA with DCM Mid-Stage Access – DCM-optimized EDFA
Besides optical amplifiers, modern optical networks also require other components to be place along the link, such as the Dispersion Compensation Module (DCM) used to correct signal distortion due to Chromatic Dispersion of the transmission fiber. Since the attenuation of DCM can be quite large, in the range of 5 to 10 dB, additional amplification […]
Variable Gain EDFA – Large Dynamic Gain Range & Better Noise Figure Performance
In order to support different span lengths between Optical Amplifiers in a transmission link, as well as to provide for aging of the link, it is desirable for an optical amplifier to support as large as possible dynamic gain range, i.e. to allow the gain to be dynamically configured over a wide range. For a […]
Raman Fiber Amplifiers – Advancements to Long Haul Transmission
Introduction Raman Fiber Amplifier (RFA) is used to assiste optical transmission system design issues such as mid-span optically amplified distance, bandwidth enhancement. The RFA does not suffer from the limitations of Erbium-Doped Fiber Amplifier (EDFA) in that it can be integrated with the transmission fibers, and pumped at any wavelength to provide wide gain bandwidth […]
Choose Ideal Optical Amplifiers by the Properties
When buying an optical amplifier, what should we consider about besides the price? Of course, it’s the quality. But how can we determine the quality good or not? Then it comes to the properties. There are mainly three aspects to consider about according to the properties of optical amplifiers. 1. Gain, Input Power and Output […]