The Dynamic Gain Equalizer (DGE) module is a high performance, digitally controlled variable gain equalizer. The module equalizes per channel power and thus optimizes the Optical Signalto-Noise Ratio (OSNR) to allow for greater distance reach. Both 40-channel and 80-channel configurations are supported by the EKINOPS PM DGE, and implementation is simple and efficient. The EKINOPS PM DGE was designed to support a wide variety of configurations and when used in conjunction with the EKINOPS PM OPM8 (Optical Power Monitor) the system allows for automatic power balancing, which is critical for mesh or metro applications. Per-channel power dynamic adjustment is already available on EKINOPS ROADM cards; the EKINOPS PM DGE complements ROADM cards for terminal sites, to provide automatic end-to-end channel optimization and OSNR margin improvement.
A Real World Example
The reference network (Figure 1) illustrates how utilizing only two EKINOPS PM DGE modules at established sites within a 20-node, 1520 km (954-mile) span can help equalize per-channel power, improving overall optical performance and achievable distance. The original specifications and design of the network required multiple optical regeneration sites between Site 1 and Site 20. By placing a DGE module at two of the sites, EKINOPS was able to eliminate the need for regen sites. The first DGE module was placed at Site 5, which adjusted for the optical power deviation for traffic coming from Site 20. The second DGE module was placed at Site 7, which, adjusted for accumulated optical power deviation for traffic coming from Site 1.
Graph. A represents the ‘Before DGE’ power measurements taken at Site 5 for traffic coming from Site 20 while Graph. B (next page) represents the ‘After DGE’ power measurements at Site 5 for the same traffic. It clearly illustrates that the per-channel optical power is equalized. As a result, there is less of a hit to OSNR for weaker channels and an overall improvement in optical performance and distance.
The EKINOPS PM DGE module can be managed through SNMP or via the EKINOPS standard element level management interfaces, which include a Command Line Interface (CLI) and an EKINOPS java-based Graphical User Interface (GUI). The CLI is accessible via Secure Socket Shell (SSH) and Telnet remotely or via a local serial port locally on the management board.
Complete performance monitoring and management are provided, including laser shut off and local and remote loopback, useful for maintenance and fault isolation.
The EKINOPS PM DGE module is also supported by Celestis NMS, the EKINOPS advanced Network Management System.
- Improves Time-to-Service
- Achieve Greater Distance
- Automatic Channel Power Balancing
- Remote Optical Power Management
- Non-Traffic Impacting Channel Re-tuning
- Point to Point, Linear, Ring, Star and Mesh Topologies
- Cell Tower | Mobile Backhaul
- Residential Backhaul
- Metro | Regional | Long Haul Networks