title: Cyclostationarity-based joint monitoring of symbol-rate, frequency offset, CD and OSNR for Nyquist WDM superchannels.
abstract: Software-defined transceivers can be reconfigured based on demand and existing channel impairments, and as such, monitoring of both signal and channel parameters is necessary. We demonstrate a novel joint estimation method suitable for spectrally efficient Nyquist wavelength-division multiplexing (WDM), based on the cyclostationary property of linearly modulated signals, exploited both in the frequency and time domains. Using a Nyquist superchannel composed of three 10 GBaud channels, we experimentally demonstrate the simultaneous monitoring of symbol-rate with 100% accuracy, roll-off, frequency offset (FO), chromatic dispersion (CD) and optical signal-to-noise ratio (OSNR) with root-mean-square errors (RMSE) of 20%, 4 MHz, 200 ps/nm and 1.5 dB respectively, when the roll-off factor is larger than 0.06 for DP-QPSK and 0.3 for DP-16QAM.
authors.forename: Maria
authors.initials: M
authors.lastname: Ionescu
authors.forename: Masaki
authors.initials: M
authors.lastname: Sato
authors.forename: Benn
authors.initials: B
authors.lastname: Thomsen