All-Optical Packet-Level Wavelength Swapping of PSK and ASK Signals in PPLN Waveguide

An all-optical solution performing wavelength swapping of signals with different modulation formats is presented. The signal swapping is obtained by cascading sum frequency generation and difference frequency generation second-order nonlinearities in periodically-poled Lithium Niobate waveguide. Data swapping of 40-Gb/s differential quadrature phase shift keying (DQPSK) and 10-Gb/s on-off keying (OOK) signals is achieved. The effectiveness of the scheme is demonstrated by means of exhaustive bit-error rate (BER) measurements at the packet level. The presented scheme is potentially polarization and wavelength independent.