Microwave signal generation via frequency-sextupling using two cascaded polarization modulators without optical filter

A high spectral purity and stable frequency-sextupled microwave signal generation approach using two cascaded polarization modulators (PolMs) is proposed. By properly adjusting the direction of polarizers, the powers and the phases of the RF driven signals, a frequency-sextupled microwave signal can be obtained without an optical filter. The performance of the signal in terms of optical sidebands suppression ratio (OSSR) and RF spurious suppression ratio (RFSSR) is theoretically analyzed, and the effects of several non-ideal factors on OSSR and RFSSR are also investigated.