A Theoretical and Experimental Study on Modulation-Format-Independent Wavelength Conversion

Modern optical networks are adopting advanced modulation formats. Future dynamic optical networks will benefit from all-optical wavelength conversion and signal regeneration techniques in support of multiple modulation formats. This paper presents a concept for a modulation-format-independent wavelength conversion technique based on an optical hybrid and an in-phase/quadrature (IQ) wavelength converter. This technique has the potential for wavelength conversion and signal regeneration of multiple modulation formats. This paper also discusses the signal distortions and noises in the semiconductor optical amplifier based IQ wavelength converter. A proof-of-principle experiment shows the wavelength conversion results of multiple modulation formats. Further, this paper presents the signal regeneration of a return-to-zero quadrature-phase-shifted-keying signal through simulation.