Simultaneous Optical and Radio Frequency Transmission Using Optical Phase Stabilization Combined With Phase Conjugation Technology

Abstract

We propose and demonstrate a new simultaneous optical and radio frequency (RF) transmission scheme using optical phase stabilization combined with phase conjugate technology. The acousto-optical modulator (AOM) is used as a frequency actuator to compensate the optical frequency phase noise introduced by the optical fiber link, and the electro-optical modulator (EOM) is used to modulate two optical carrier sidebands simultaneously to stabilize the RF phase by phase conjugate technology. The novelty is that forward and backward RFs are distinguished by the AOMs used in standard optical carrier transfer to avoid the backscattering without WDM, so that the optical link is more symmetric, reducing the degradation of frequency stability due to polarization fluctuation and chromatic dispersion thermal sensitivity. We experimentally demonstrate 193.4 THz optical frequency transfer with a frequency stability of 1.2 $ \times $ 10−17 at the integral time of 1 s and 3.3 $ \times $ 10−19 at 10000 s, 1 GHz RF with a frequency stability of 7 $ \times $ 10−13 at 1 s and 3 $ \times $ 10−16 at 10000 s over a 50.4 km fiber spools. This novel scheme demonstrates the compatibility of two contrasting fiber noise cancellation techniques, and is superior to the current optical frequency and RF simultaneous transmission schemes in terms of cost and complexity.

Keywords

• Optical frequency transfer
• radio frequency transfer
• simultaneous transfer