Superchannel coherent modulation analysis

Tektronix has a new software option for its OM4000 optical modulation analyser series that offers automated test support for 400G multi-carrier coherent optical modulation. This software option will greatly reduce test times for researchers working on 400G and faster coherent optical systems while providing the flexibility to define carrier count, carrier spacing and modulation formats. It also provides compiled carrier measurement results and multi-carrier visualisation for integrated analysis.

The new software is available to Tektronix customers as Option MCS on the OM4106D Coherent Lightwave Signal Analyser and OM1106 Coherent Lightwave Signal Analyser Software. The OM4106D is tightly integrated with Tektronix DPO70000D Series 33 GHz oscilloscopes and uses coherent detection to acquire fiber signals carrying up to 240 Gb/sec per wavelength.

“The explosive growth of mobile and cloud computing continues to drive long-haul optical communications bandwidth demands, leading to new designs which leverage existing infrastructure using coherent optical technology,” said Brian Reich, general manager Performance Oscilloscopes, Tektronix. “We see 400G as the next big milestone and superchannel technology as the most likely winner, at least in the near term. This new software will go a long way toward helping to advance multi-carrier modulation methodologies as new standards emerge.”

Multi-carrier 400G Gaining Support
With 100G now heading into deployment, network equipment manufacturers are investigating ways to achieve networks speeds of 400G and beyond. Instead of simply increasing the symbol rate of a single carrier, one proposal gaining momentum is to transmit in parallel by using multiple carriers at lower individual rates. Multi-carrier systems such as this have been dubbed superchannels.


There is currently no industry consensus on how to build superchannels. Vendors differ on characteristics as basic as carrier count and carrier spacing to what modulation format should be used. Therefore, a measurement system must have the flexibility to adapt to all these formats. With Option MCS, Tektronix is the industry’s first test supplier to offer multi-carrier or superchannel support.


Fast, Automated Results
Option MCS software is designed for optimum ease-of-use and flexibility. To launch tests, the user simply enters multi-carrier variables such as number of carriers, carrier spacing, and modulation format in a simple table. The software automatically steps through each carrier; setting up the local oscillator and measurement parameters based on the information entered into the carrier information table. When all measurements are complete, the system provides the results from all carriers side-by-side for easy correlation and quick identification of problems.