An optically tunable wideband optoelectronic oscillator based on a bandpass microwave photonic filter

作者:Jiang Fan; Wong Jia Haur; Lam Huy Quoc; Zhou Junqiang; Aditya Sheel; Lim Peng Huei; Lee Kenneth Eng Kian; Shum Perry Ping; Zhang Xinliang*
来源:Optics Express, 2013, 21(14): 16381-16389.
DOI:10.1364/OE.21.016381

摘要

An optoelectronic oscillator (OEO) with wideband frequency tunability and stable output based on a bandpass microwave photonic filter (MPF) has been proposed and experimentally demonstrated. Realized by cascading a finite impulse response (FIR) filter and an infinite impulse response (IIR) filter together, the tunable bandpass MPF successfully replaces the narrowband electrical bandpass filter in a conventional single-loop OEO and serves as the oscillating frequency selector. The FIR filter is based on a tunable multi-wavelength laser and dispersion compensation fiber (DCF) while the IIR filter is simply based on an optical loop. Utilizing a long length of DCF as the dispersion medium for the FIR filter also provides a long delay line for the OEO feedback cavity and as a result, optical tuning over a wide frequency range can be achieved without sacrificing the quality of the generated signal. By tuning the wavelength spacing of the multi-wavelength laser, the oscillation frequency can be tuned from 6.88 GHz to 12.79 GHz with an average step-size of 0.128 GHz. The maximum frequency drift of the generated 10 GHz signal is observed to be 1.923 kHz over 1 hour and its phase noise reaches the -112 dBc/Hz limit of our measuring equipment at 10 kHz offset frequency.

  • 出版日期2013-7-15
  • 单位南阳理工学院