First numerical investigations are undertaken to analyze and compare the performance and cost of 3-level Duobinary and PAM-4 formats as candidates for high-speed next-generation PONs that support downstream 28 Gb/s and 40 Gb/s per wavelength signal transmission over standard SMF in the C-band.
Transceivers with bandwidths of 10 GHz, 20 GHz, 28 GHz and 40 GHz have been analyzed, showing the feasibility of PON-distance transmission with low-cost band-limited components. Duobinary achieves better sensitivities for smaller distances, whereas PAM-4 shows better results for larger distances. In addition, Duobinary and PAM-4 have similar transceiver cost.