Optical amplifiers are used in amplified nodes such as hub nodes, amplified OADM nodes, terminal nodes, and line amplifier nodes. The optical amplifier card architecture includes an optical plug-in module with a controller that manages optical power, laser current, and temperature control loops. The amplifier also manages communication with the TCC2, and operations, administration, maintenance, and provisioning (OAM&P) functions such as provisioning, controls, and alarms. The OPT-PRE is a C-band DWDM, two-stage erbium-doped fiber amplifier (EDFA) with mid-amplifier loss (MAL) for allocation to a dispersion compensation unit (DCU). To control the gain tilt, the OPT-PRE is equipped with a built-in VOA. The VOA can also be used to pad the DCU to a reference value.
Fixed gain mode with programmable tilt;
True variable gain;
Fast transient suppression;
Nondistorting low-frequency transfer function;
Settable maximum output power;
Fixed output power mode (mode used during provisioning);
Constant drive current mode (test mode);
MAL for fiber-based DCU;
Amplified spontaneous emissions (ASE) compensation in fixed gain mode;
Full monitoring and alarm handling with settable thresholds;
Optical safety features that include signal loss detection and alarming, fast power down control and reduced maximum output power in safe power mode;
Four signal photodiodes to monitor the input and output optical power of the two amplifier stages through CTC;
An optical output port for external monitoring.