Optical temporal encoding/decoding of short pulses using cascaded long-period fiber gratings

A novel, optical temporal encoding/decoding method is proposed and demonstrated. This can be accomplished by passing a short optical pulse through cascaded long-period fiber gratings. It has the advantages of constructing ultrafast codes and developing resistance to interferometric perturbations among the coded pulses. To verify the feasibility as a code generator, two types of codes are generated and compared with the predicted code patterns. In addition, to show an application for an optical code-division-multiplexing system, decoding performances with matched and unmatched decoders are compared.