Experimental analysis of all-optical 4-ASK signal generation through parametric amplification

we present experimental results concerning a new alloptical technique that multiplexes two binary signals into a quaternary one (4-ask). the technique is based on parametric amplification. values of the quaternary levels obtained experimentally, as a function of the extinction ratios of the binary input signals, show a rather good agreement with the simulated and the analytical results. the generated 4-ask signals were propagated through 75 km of standard single-mode fiber and experienced eye penalties of only 0.5 db. this indicates the robustness of the technique for practical applications in metropolitan area networks.