Frequency down-conversion system with image rejection using thin film lithium niobate parallel modulation phase-shifting structure
Xiang, Zichuan; Jia, Qianqian; Li, Jinye; Li, Run; Liu, Jianguo Source: Optics Communications, v 569, October 15, 2024; ISSN: 00304018; DOI: 10.1016/j.optcom.2024.130820; Article number: 130820; Publisher: Elsevier B.V.
Author affiliation:
Laboratory of Nano Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing; 100083, China
College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract:
The frequency down-conversion system based on microwave photonics has been widely employed in radar, electronic warfare, and satellite communication systems. In this paper, we propose an image rejection frequency down-conversion system, wherein the phase modulator and phase shifter are integrated on thin film lithium niobate platform. The working principle is elucidated through the establishment of a theoretical model. Subsequently, the system successfully down-converts a 40 GHz radio frequency (RF) signal to a 5 GHz intermediate frequency signal, achieving an image rejection ratio of approximately 30 dB. Simultaneously, varying degrees of image rejection are observed for different RF signals. The system maintains robust image rejection performance across varying RF and image signal power, as well as different levels of input optical power.