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 […]
Passive and Active Network Fundamentals
Today we have access to more information than ever before. We live in a digital world and bandwidth is what makes a digital world happen. Aging copper networks are being taxed by residential and business customers. However, Passive Optical Network (PON) such as Fiber-To-The-Home (FTTH) are increasingly being deployed to meet the current and future […]
Advanced Optical Components – Optical Isolator
Connectors and other types of optical devices on the output of the transmitter may cause reflection, absorption, or scattering of the optical signal. These effects on the light beam may cause light energy to be reflected back at the source and interfere with source operation. To reduce the effects of the interference, an Optical Isolator […]