Lucent Technologies' Bell Labs Demonstrates First Transmission of 100 Gb/s Ethernet-over-optical

In two papers presented to the European Conference and Exhibition on Optical Communication (ECOC) in Scotland, Lucent Technologies' Bell Labs announced the first reported transmissions of 100 Gb/s Ethernet over optical.

The Bell Labs research team was able to deliver a 107 Gb/s optical data stream, representing 100 Gb/s of data transmission plus a standard 7 percent overhead for error correction, using the following two technological approaches:

• Duobinary Signaling: This technique uses three electrical signal levels, — positive, negative and zero — to represent a binary signal for communications transmission. Duobinary signals require less bandwidth than traditional NRZ (non-return to zero) signals. The application of this bandwidth-compressing format enabled the creation of an optical 107-Gb/s serial data stream using a commercially available optical modulator (rated for 40 Gb/s).
• Single-Chip Optical Equalizer: Integrated optical equalizers invented by Bell Labs researchers two years ago, can compensate for transmission impairments and also for the limited modulator bandwidth in a commercially available NRZ system. NRZ is the least complex optical data format to generate. In order to demonstrate an optical 107-Gb/s NRZ signal, Bell Labs designed a single chip optical equalizer that compensated for almost all inter-symbol interference arising from modulator bandwidth limitations in an optical 107 Gb/s NRZ electronic time division multiplexing (ETDM) transmitter. As with the duobinary approach, Bell Labs researchers used a commercially available 40-Gb/s optical modulator in combination with the optical equalizer to generate a 107-Gb/s optical NRZ data stream.

The ECOC-submitted papers on both of these approaches are available upon request.

Source: Lucent Technologies

Write a comment below. No registration needed!