A Novel Coherent Ladar System with High Repetition Frequency and Wide Bandwidth
LI Guangzuo① MO Di② WANG Ning② WANG Ran② ZHANG Keshu② ZHANG Zenghui① WU Yirong①②
①(School of Electronic Information and Electrical Engineering, Shanghai Jiaotong University, Shanghai 200240,China) ②(Insititute of Electronics, Chinese Academy of Sciences, Beijing 100190, China)
Abstract：A novel coherent ladar system with high repetition and wide bandwidth is proposed. Based on the I&Q modulator from the fiber communication community and the bandwidth synthesis technique, the proposed system provides wide bandwidth with high repetition rate, which is difficult for conversional ladar system based on tuning the wavelength of a tunable laser. The proposed system is expected to be useful for high range resolution imaging, Inverse Synthetic Aperture Ladar (ISAL), range resolved vibration measurement. The operation principle, system description, and signal processing method for bandwidth synthesis are discussed in the paper. And experiments are performed both in fiber delay line and free space. As a demonstration, the system generates signal with 6 GHz at repetition rate of 16.7 kHz. The resolution of the obtained images is finer than 2.5 cm. The experimental results demonstrates the effectiveness of the proposed system and the processing method.
李光祚, 默迪, 王宁, 王然, 张珂殊, 张增辉, 吴一戎. 一种新的高重频宽带相干激光雷达系统研究[J]. 电子与信息学报, 2018, 40(3): 525-531.
LI Guangzuo, MO Di, WANG Ning, WANG Ran, ZHANG Keshu, ZHANG Zenghui, WU Yirong. A Novel Coherent Ladar System with High Repetition Frequency and Wide Bandwidth. JEIT, 2018, 40(3): 525-531.
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