Broadband information distribution networks employing optical frequency division multiplexing technologies

The authors consider the configuration of the OFDM (optical frequency division multiplexing) broadband distribution networks, including the communication service, and discuss the following OFDM technologies: a multichannel frequency stabilization technique, a polarization-insensitive waveguide FS-SW (frequency selection switch), and an FSK (frequency-shift keying)/direct-detection scheme using a Mach-Zehnder filter. The waveguide FS-SW, consisting of seven Mach-Zender filters, successfully selected channels with a total crosstalk of less than -13 dB. The balanced receiver configuration of the OFD (optical frequency discriminator) receiver is 3 dB more sensitive than single-detection-type OFDs, such as a Fabry-Perot-filter-type discriminator. A 100-channel OFDM transmission/distribution experiment at 622 Mb/s over a 50 km fiber length was performed