Advanced Photonics Nexus, Volume. 4, Issue 2, (2025)

Microwave photonic prototype for concurrent radar detection and spectrum sensing over an 8 to 40 GHz bandwidth [Early Posting]

Shi Taixia, Liang Dingding, Wang Lu, Li Lin, Guo Shaogang, Gao Jiawei, Li Xiaowei, Lin Chulun, Shi Lei, Ding Baogang, Liu Shiyang, Yang Fangyi, Jiang Chi, Chen Yang
Author Affiliations
  • East China Normal University
  • Beijing Institute of Control Engineering
  • Shanghai Lujie Communication Technology Company Limited
  • show less

    A microwave photonic prototype for concurrent radar detection and spectrum sensing is proposed. A direct digital synthesizer and an analog electronic circuit are integrated to generate an intermediate frequency (IF) linearly frequency-modulated (LFM) signal ranging from 2.5 to 9.5 GHz, with an instantaneous bandwidth of 1 GHz. The IF LFM signal is converted to the optical domain via an intensity modulator and filtered by a fiber Bragg grating (FBG) to generate two 2nd-order sidebands. The two sidebands beat each other to generate a frequency-and-bandwidth-quadrupled LFM signal. By changing the center frequency of the IF LFM signal, the radar function can be operated within 8 to 40 GHz. One 2nd-order sideband works in conjunction with the stimulated Brillouin scattering gain spectrum for microwave frequency measurement, providing an instantaneous measurement bandwidth of 2 GHz and a frequency measurement range from 0 to 40 GHz. The prototype is demonstrated to be capable of achieving a range resolution of 3.75 cm, a range error of less than ±2 cm, a radial velocity error within ±1 cm/s, delivering clear imaging of multiple small targets, and maintaining a frequency measurement error of less than ±7 MHz and a frequency resolution of better than 20 MHz.

    Paper Information

    Manuscript Accepted: Dec. 3, 2024

    Posted: Jan. 23, 2025

    DOI: APN