Noise-sideband-free and narrow-linewidth photonic microwave generation based on anoptical heterodyne technique of low-noise fiber lasers

Abstract

Noise-sideband-free and narrow-linewidth photonic microwave generation based on an optical heterodyne technique is demonstrated experimentally. By beating a self-injection-locking low-noise single-frequency fiber laser and a Brillouin fiber laser, a 9.4 GHz microwave is produced, and its noise sidebands are completely suppressed. Additionally, the signal-to-noise ratio of the microwave signal is improved by 15 dB from 40 to 55 dB, and the linewidth is compressed from 1.6 to 0.53 kHz. The high-performance photonic microwave based on low-noise fiber lasers is a promising candidate in further applications such as wireless network, lidar, and satellite communication.

Narrow Linewidth Half-Open-Cavity Random Laser Assisted by a Three-Grating Ring Resonator for Strain Detection

“…A narrow linewidth is beneficial to suppress frequency noise levels of fiber lasers and can further improve resolution in optical dynamic strain-sensing systems [ 1 , 2 , 3 ]. Random fiber lasers (RFLs) have a simple cavity configuration, low threshold, and good temporal coherence, and they are a promising alternative for narrow linewidth and low frequency noise fiber lasers [ 4 , 5 , 6 ].…”