In addition to these hardware modules, the system implements a software-based Pre-Emphasis (PE) algorithm that provides an additional control loop, allowing the system to pre-compensate for spectral tilt and ripple. With these hardware and software features, the CN 4200’s transport capability can be extended up to 1600 kilometers without regeneration.

The OAs are available in fixed- and variable-gain versions. The OAF-BC-HP fixed-gain amplifier provides 14 and 17 dB gain with 20 dBm output, and the OAV-VS-HP variable-gain amplifier provides 25 dB gain with 20 dBm output. Both versions provide:

• Ciena’s SmartGain™ control circuitry to maintain a constant gain across the transport spectrum regardless of input power
• Span loss compensation to mitigate the effects of aging spans by dynamically adjusting the gain of a span-receive amplifier and offset increased loss
• Auto Power Shut Down (APSD)
• Remote and local management
• Autonomous alarms and Threshold Crossing Alerts (TCAs)
• Input/output power histories
• Optical Channel Monitor (OCM) input/output ports

In addition, the OAV-VS-HP provides midstage access for the external Dispersion Compensation Module (DCM) and midstage loss borrowing for extended reach up to 35 dB on qualifying spans without the need for the Raman. It also offers an integrated Optical Supervisory Channel (OSC) for out-of-band node management, and acts as the system controller when installed in the CN 4200 or CN 4200 MC main slot.

The CN 4200 OAs amplify the entire C-band Dense Wavelength Division Multiplexing (DWDM) channel plan. The modules are functionally compatible with existing fixed-filter Optical Add/Drop Multiplexers (OADMs), VMUX OADMs, and the Reconfigurable OADM (ROADM)1. In addition, the OAs are physically compatible with the existingCN 4200, CN 4200 MC, and CN 4200 RS form factor chassis, and functionally compatible with the existing auto channel power control and span loss compensation features. Architecturally, the OAs are ready to support both 50 GHz channel plans and 40G transport.

The Raman provides distributed amplification of the payload signal—and to a lesser extent, the OSC channel—by pumping the transmission fiber to increase the power of the 1550-band payload. The Raman wavelengths inject up to 27 dBm (500 mW) of optical power and are transmitted counter-propagating to the signal path. Additionally, the Raman provides 8 to 10 dB of Raman fiber gain, depending on fiber type and span loss, and is designed to operate at maximum, or best-effort, gain. The Raman is compatible with Non-Dispersion Shifted Fiber (NDSF), ELEAF, TW, TW-C, LS and Dispersion Shifted Fiber (DSF) fiber types.

Ciena may make changes from time to time to the products or specifications contained herein without notice.