The xDSM waveform is composed of multiple narrowband subcarrier signals that are less sensitive to channel impairments. The trend in DWDM has been to maximize the number of channels while simultaneously increasing the data rate on each channel. The xDSM technology increases speed on each wavelength using less optical spectrum, enabling long-haul providers to continue to increase capacity on existing fiber networks. The xDSM technology provides several important cost and performance benefits for network providers. Its bandwidth efficient modulation yields significant cost savings by providing higher data rates using lower frequency optoelectronics.
Network providers can deliver signals that are data rate and protocol independent.
This allows rapid, independent provisioning of subcarrier channels. Additionally, only one network element needs to be provisioned in order to reconfigure the network. It is possible to provision xDSM waveforms on any or all of the wavelengths of a DWDM network. Greater reach is achieved on dispersion-limited channels. While xDSM technology has great potential, risk factors exist that may limit product performance and broad market acceptance.