Integrated-optic OFDM demultiplexer using multi-mode interference coupler-based optical DFT circuit

We report a silica-PLC OFDM demultiplexer comprising an N × N multi-mode interference coupler-based DFT circuit. The demultiplexer, which can demultiplex four OFDM sub-carriers simultaneously, is realized and applied to 4 × 10-Gbit/s signal demultiplexing.