RF-down and RF-up converting optoelectronic oscillator for spurious suppression

This paper describes an RF-down and RF-up converting optoelectronic oscillator (OEO) using a band-pass filter (BPF) for spurious suppression. This OEO is able to suppress the spurs with the BPF whose fractional bandwidth is wider than that of the BPF in a conventional OEO. This fractional bandwidth broadening of the BPF leads to the allowance of using a long optical fiber, that is, leads to achieve lower phase noise without the spurs. A fabricated 10GHz proposed OEO demonstrates more than 32 dB spurious suppression compared with a fabricated 10GHz conventional OEO.