Photonic microwave frequency measurement with improved resolution based on bandwidth-reduced stimulated Brillouin scattering

Abstract

We propose and theoretically demonstrate a photonic-assisted frequency measurement system based on stimulated Brillouin scattering (SBS) with high accuracy, high resolution, and the capability of multiple frequencies estimation. The great performance is achieved by superimposing the gain spectrum with two loss spectrums for SBS gain bandwidth reduction. Meanwhile, the frequency information of multiple unknown signals is obtained by the bandwidth-reduced gain spectrum of the acoustic-optic interaction in the SBS process. Ultimately, the result show that the system is competent in identifying the frequency information among multiple unknown RF signals with high resolution of 14.5 MHz, high accuracy of 8 MHz, and the bandwidth of 20 GHz. Considering the comprehensive performance of this system, which is beneficial for applications in modern communication and radar applications.