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Optical performance monitoring in elastic optical OFDM networks

Optical performance monitoring (OPM) is a crucial element in network management, in order to assure the quality of the optical signals at various intermediate and destination nodes. In future elastic optical network, the network operation is more adaptive and reconfigurable. The OPM monitoring information retrieved at each intermediate node would be useful for optimal network control. Common OPM parameters in an optical transmission system, include optical signal-to-noise ratio (OSNR), accumulated chromatic dispersion (CD) and polarization mode dispersion (PMD). In this paper, we present our OPM techniques for these three parameters, based on signal correlation procedures on one or a few pilot subcarriers inserted in the spectrum of an optical OFDM signal, which is one of the promising signal format to support the future elastic optical networks.