A photonic broadband signal frequency conversion and bandwidth multiplication system is demonstrated based on a Fourier domain mode-locked optoelectronic oscillator (FDML-OEO). In this method, frequency conversion is achieved by using the selected optical sideband as the optical source of the FDML-OEO. An experiment is conducted, and a linear frequency modulation (LFM) signal with different central frequencies are converted. The central frequency of the converted signal can be tuned simply by adjusting the wavelength of the optical carrier. Due to the feature of low phase noise of the OEO, the degradation of the converted signal is almost neglected. Broadband signals with different time widths are also converted in terms of fibre length regulation. Furthermore, bandwidth multiplication of the LFM signal is achieved by selecting a second-order optical sideband as the optical source of the FDML-OEO.
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