The OSA-710 is the first instrument to be able to measure in-band OSNR on live, coherent systems that use polarization-multiplexed (Pol-Mux) transmission formats. It's also the first instrument to measure in-service chromatic dispersion on high-speed network traffic containing Pol-Mux signals, Viavi adds.The OSA-710 uses a new, non-intrusive Spectral Correlation Method (SCorM) (Viavi patent US 20160164599 A1) to enable in-service and in-band OSNR measurements. The method is
independent of modulation format and data rate, and is tolerant to large amounts of chromatic dispersion and pulse mode dispersion, as well as spectral filtering in ROADMs. It tests all traffic types, including Nyquist-channels and superchannels in presence of ROADM filtering without service/network disruption and can quickly identify traffic types (data-rate and symbol-rate) in mixed-traffic systems.
Judge's comment: "Viavi's spectral correlation measurement method is truly innovative. It solves a very challenging problem: non-disruptive in-band measurement of OSNR in a modern ROADM-based coherent transmission system. This is a meaningful advancement to the optical measurement field and will be highly valuable to the network operators."
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