Basic function

* Integrates a backward Raman unit and an EDFA unit and amplifies the input optical signals in C band. The total wavelengths
range from 1529 nm to 1561 nm.
* Supports the system to transmit services over different fiber spans without electrical regeneration.
* Generates multi-channel pump light of high power, providing energy for the amplification of signals in the fiber.
* The TN12RAU2 board supports the interlock switch. The interlock switch of a LINE port on the panel controls the power-on and
power-off of the board and prevents eyes from being injured by laser when an optical fiber is inserted into or removed from the
LINE port.

Gain adjustment

The RAU2 continuously adjusts the gain continuously based on the input optical power: * G.652 fibers: 30dB to 41dB
* LEAF fibers: 32dB to 43dB
* G.653 fibers: 32dB to 43dB
* TWRS fibers: 32dB to 43dB
* TW-C fibers: 32dB to 43dB
* TWPLUS fibers: 32dB to 43dB
* SMFLS fibers: 32dB to 43dB
* G.656 fibers: 32dB to 43dB
* G.654A fibers: 30dB to 41dB
* TERA_LIGHT fibers: 32dB to 43dB
* G.654B fibers: 27dB to 37dB

NOTE:Users can separately configure the gain adjustment point for the Raman amplifier and EDFA using the NMS.

Online optical performance monitoring

Provides an in-service monitoring port (MON). This port connects to an optical spectrum analyzer or spectrum analyzer unit to
monitor the spectrum and optical performance of the multiplexed signal without affecting traffic.

Working mode

The Raman amplifier optical module supports the gain locking, maximum gain, and power locking modes. * In gain locking mode. This
mode applies to multi-span or single-short-span systems that use
G.652/G.653/LEAF/TWRS/TW-C/TWPLUS/SMFLS/G.656/G.654A/TERA_LIGHT/G.654B fibers. In addition, the gain of the Raman unit is
tunable and users can query the actual gain of the Raman unit.
* The maximum gain mode
applies to ultra-long-single-span systems that use G.652/G.653/LEAF/TWRS/TW-C/TWPLUS/SMFLS/G.656/G.654A/TERA_LIGHT/G.654B
fibers. In this mode, the Raman amplifier module automatically adjusts its pump power to ensure that its gain reaches the
maximum value. In addition, users can query the actual gain of the Raman amplifier module.
* In the pump power mode.
This mode applies to systems that use any fibers but the G.652/G.653/LEAF/TWRS/TW-C/TWPLUS/SMFLS/G.656/G.654A/TERA_LIGHT/G.654B
fibers or to situations in which the pump power of the Raman amplifier module must be adjusted manually.

The EDFA optical module supports the gain locking and power locking modes. * In the gain locking mode, the gain of the EDFA module
is tunable and users can query the actual gain of the EDFA module. The gain locking mode is enabled by default.
* The power locking mode is used for the commissioning
and fault location purposes.

Transient control function

The EDFA inside the board has the transient control function. When channels are added or dropped, the board can suppress the
fluctuation of the optical power in the path so as to implement the smooth upgrading and expansion.

Alarms and performance events monitoring

* Detects the pump driving current, back facet current, pump cooling current, temperature of the pump laser and the ambient
temperature of the board.
* The EDFA optical module can detect and report optical power.
* The Raman amplifier optical module of the RAU2 board supports return loss detection.

Line fiber quality monitoring function

The OTDR function can be used on the U2000. Monitoring figures and data are displayed on the U2000. For details, see the Fiber
Doctor System in the Feature Description.
The Fiber Doctor Management System Software Fee License needs to be purchased for this function.

FCD function

The FCD button and indicator are provided. You can press the FCD button on the front panel to trigger FCD. The detection process
and results can be identified by the FCD indicator blinking frequency and indicator status. For details, see Front Panel.

Safe turn-on of the Raman laser

When the Raman laser is turned on, the OTDR meter function is automatically enabled to detect fiber connections and therefore
ensure that the laser is properly started, avoiding fiber burning due to inappropriate fiber connections.
If the Raman laser fails to be turned on, the line fiber quality monitoring function can be used to further identify fault points.

Quick shutdown of the Raman laser

The quick shutdown of the Raman laser is supported. When fiber removal or fiber cut occurs within 500 m around the site where the
board housing the Raman laser is located, the pump light of the Raman laser can be shut down within 100 ms.

Optical-layer ASON

Supported

NOTE:Only the TN12RAU2 board supports the following functions: line fiber quality monitoring function, FCD, safe turn-on of the Raman laser, and quick shutdown of the Raman laser.