Blind modulation format identification for digital coherent receivers

• DOI: 10.1364/oe.23.026769
• Publication Date: 2015-10-02T18:48:20Z
• Authors: Syed Muhammad Bilal; Gabriella Bosco; Zhenhua Dong; Alan Pak Tao Lau; Chao Lu
• Keywords: 0103 physical sciences; 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology; 01 natural sciences; Coherent communications; Modulation; Fiber optics links and subsystems.

In this paper, a simple novel digital modulation format identification (MFI) scheme for coherent optical systems is proposed. The scheme is based on the evaluation of the peak-to-average-power ratio (PAPR) of the incoming data samples after analog-to-digital conversion (ADC), chromatic dispersion (CD) and polarization mode demultiplexing (PMD) compensation at the receiver (Rx). Since at a particular optical-signal-to-noise ratio (OSNR) value different modulation formats have distinct PAPR values, it is possible to identify them. The proposed scheme and the results are analyzed both experimentally and through numerical simulations. The results demonstrate successful identification among four modulation formats (MF) commonly used in digital coherent systems.