Transmission of signal and idler using optical parametric amplifier based on PPLN waveguide

In this study, we attempted the repeated transmission of S-band signals by compensating for the loss of the transmission fiber using an optical parametric amplifier (OPA) based on a periodically poled LiNbO₃ waveguide. We examined and compared the two configurations. The first method involved wavelength conversion of the signal to an idler, while the second method amplified the signal itself. In the latter case, we demonstrated repeated transmissions using external dispersion compensation. In the former case, we demonstrated that it was possible not only to compensate for fiber loss but also to reduce the accumulation of dispersion in transmission fibers by utilizing spectral inversion.