Seamless all-optical bidirectional wavelength converter

We proposed a seamless all-optical wavelength converter based on four wave mixing effect in highly nonlinear fibers. The proposed wavelength converter consists of a section of highly nonlinear fiber to implement bi-directionally wavelength conversion twice for seamless conversion. The seamless wavelength converter was utilized for orthogonal frequency division multiplexing signals with flexible spectra to defragment their optical spectra. The bidirectional scheme of the seamless wavelength converter costs less highly nonlinear fibers, so as to reduce the system size and cost.