The VIAVI Pol-Mux OSCA-710 is the first Optical Spectrum and Correlation Analyzer that can perform in-band OSNR measurement in high speed, ROADM based DWDM networks using polarization multiplexing transmission formats without shutting down optical channels. This module uses a novel, proprietary spectral correlation measurement technique (VIAVI pat.) along with an ultra-high resolution coherent receiver for complete signal characterization in amplitude, frequency, phase and polarization.