Bidirectional Radio Frequency Up-Converted Orthogonal Frequency-Division Multiple Access Passive Optical Network With Novel Source-Free Optical Network Units Using Four-Wave Mixing in Semiconductor Optical Amplifier

We propose and demonstrate a bidirectional radio-frequency (RF) up-converted orthogonal frequency-division multiple access passive optical network (OFDMA-PON) system. Novel source-free optical network units (ONUs) are configured in the proposed OFDMA-PON system, which can support simultaneous and interference-free upstream transmission from multiple ONUs over a single wavelength in a single-fiber topology. The four-wave mixing effect in a semiconductor optical amplifier is utilized in the optical line terminal to enable its configuration. Experimental results successfully verify the feasibility of our proposed system.