Chaotic Power Division Multiplexing for Secure Optical Multiple Access

This paper proposes a novel chaotic power division multiplexing (CPDM) for secure optical multiple access. The proposed CPDM can not only improve spectral efficiency and the user number by multiplexing spectrally overlaid OFDM signals at different power ratio, but also ensure the information security of the users by implementing chaotic encryption on the physical layer. The key space of the encryption scheme is up to
${10^{98}}$
, which can effectively resist the illegal acceptance. Furthermore, to meet future data traffic and multiple access demands, we first explore the beneficial combination of power dimension and mode dimension. A 30 Gb/s secure chaotic power division multiplexing and mode division multiplexing passive optical network (CPDM-MDM-PON) transmission over 5 km weakly coupled few-mode fiber (FMF) is experimental demonstrated. Experimental results show that, the proposed PON system has the appealing potential to attain high spectral efficiency and large traffic capacity and serve more users. The nonlinearity transmission impairments of single mode fiber and FMF are also investigated in this paper.