Increasing the Capacity in NG-PON Using QPSK, 4-QAM, and 8-QAM Modulation Formats

This work demonstrates the potential of a dual-polarized multilevel modulation format with coherent detection (CD) to maximize the spectral efficiency to meet the demand of the next-generation passive optical network (NG-PON). Maximizing capacity and spectral efficiency in NG-PON networks is particularly crucial for improving high-speed internet access, bridging the digital divide, and enabling new services and opportunities in rural and underserved areas, ultimately contributing to their socio-