April 7, 2019

Introduction to Optical Amplifier (BA, LA, and PA)

Optical Amplifier (OA) is an important composition in WDM Transmission Network, it amplifies optical signals. TARLUZ Optical Amplifiers featured with real-time, high gain, broad width, on-line, low noise, and low attenuation. It is an essential component in a new-generation optical fiber communication system. based on the position of the Optical Amplifiers in the optical link, we have BA (Booster Amplifier), LA (Line Amplifier) and PA (Pre-amplifier).

Booster Amplifier is installed in the transmitting side of the fiber optic network, which can amplifying the optical signal before it launched into the fiber link. It is usually used in DWDM network where the multiplexer attenuates the signal channels. The above picture shows a DWDM network using booster amplifier (BA) at the transmitting end and pre-amplifier (PA) at receiving end. Please be noted that the DCM (Dispersion Compensation Module) is added in this network to further ensure the transmission quality. A booster amplifier usually provides low gain and high output power.

Line Amplifier or In-line Amplifier is easy to understand. The gain provided by the pre-amplifier and booster amplifier might not be enough due to the optical loss caused by long haul transmission. In-line amplifier is installed in the fiber optic link every 80-100km as shown in the above picture. It has moderate gain and has similar output power to those of booster amplifier.

Pre-Amplifier is usually installed at the receiver side of the DWDM network to amplify the optical signal to the required level to ensure that it can be detected by the receiver. The above picture shows a typical diagram for a duplex DWDM network. A pre-amplifier is installed at each receiving end of this network. There will be great power loss after the optical signal goes through the a long distance optical fiber transmission. Then, pre-amplifier installed at the receiver end is necessary. Generally, a pre-amplifier should offer high gain to ensure that the optical signal is detectable.