One‐third optical frequency divider for dual‐wavelength optical signals based on an optoelectronic oscillator

Abstract

An optical frequency divider for dual-wavelength optical signals based on an optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. The Mach-Zehnder modulator in the OEO is biased at the minimum transmission point, the OEO-based frequency divided signal originates from system noise. When the oscillation phase and amplitude conditions met, it gets stabilised at an oscillation frequency which is one-third of the frequency interval of the injected dual-wavelength optical signal. A proof-of-concept experiment is verified. With the frequency interval of the dual-wavelength optical signal ranging from 101.4 to 120.6 GHz, the RF signals ranging from 33.8 to 40.2 GHz are successfully generated. The power ripple is lower than 2.92 dB and the rejection ratio of the harmonic components is larger than 39 dB for all the conditions. The phase noise values of the generated RF signals are kept to be around −105 dBc/Hz@10 kHz.

Photonic‐assisted one‐third microwave frequency divider

“…Since the amplitude of the optical carrier at the output of the DPMZM is also dependent on V b2 , V b2 is used to make the carrier to have the same amplitude as the sideband. Therefore, the main MZM bias voltage V b3 is used to control the roundtrip phase of the frequency divided signal to satisfy the phase condition given in (7). This is different from the previously reported injection locking and regenerative photonic microwave frequency dividers [3][4][5][6][7], which use an EPS or an OVDL to control the round-trip signal phase to satisfy the phase condition.…”

“…Therefore, the main MZM bias voltage V b3 is used to control the roundtrip phase of the frequency divided signal to satisfy the phase condition given in (7). This is different from the previously reported injection locking and regenerative photonic microwave frequency dividers [3][4][5][6][7], which use an EPS or an OVDL to control the round-trip signal phase to satisfy the phase condition. Using V b3 to control the microwave signal phase has a number of advantages over the conventional electrical approaches.…”

“…It can be seen from Figure 1 that the frequency divider is implemented by a DPMZM and an MZM connected in series. To our knowledge, three microwave frequency dividers based on cascaded modulators have been reported [6,7,9], but all require using an EPS to control the round-trip phase for generating a frequency-divided signal.…”

“…Several photonics-based microwave frequency divider structures have recently been reported. Most of them use an optoelectronic oscillator (OEO) to realise frequency division through injection locking [2,3] or based on regenerative technique [4][5][6][7]. Both techniques require a precise control of the gain and phase, a condition needed for frequency division at a given input frequency.…”