Author Affiliations
Abstract
1 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
3 Songshan Lake Materials Laboratory, Dongguan 523808, China
4 School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071, China
We demonstrate a harmonically pumped femtosecond optical parametric oscillator (OPO) laser using a frequency-doubled mode-locked Yb:KGW laser at a repetition rate of 75.5 MHz as the pump laser. Based on a bismuth borate nonlinear crystal, repetition rates up to 1.13 GHz are realized, which is 15 times that of the pump laser. The signal wavelength is tunable from 700 nm to 887 nm. The maximum power of the signal is 207 mW at the central wavelength of 750 nm and the shortest pulse duration is 117 fs at 780 nm. The beam quality (M2 factor) in the horizontal and vertical directions of the output beam are 1.077 and 1.141, respectively.
GHz femtosecond laser optical parametric oscillator tunable wavelength Chinese Optics Letters
2020, 18(3): 033201
1 电子信息控制重点实验室，成都610036
2 电子工程学院，合肥230037
为了迅速对雷达辐射源进行识别，减少处理环节，提出一种基于自提取样本图的雷达辐射源识别新方法。算法直接从全脉冲数据中提取脉冲样本图，而后利用自提取样本图进行匹配识别。这种方法无需传统方法的特征提取过程，且不需对雷达信号进行分选，简化了处理环节，能够节约处理过程的时间。仿真分析表明，该方法能够获得较高的识别率。
雷达识别 电子侦察 分选 自提取 脉冲样本图 radar emitter recognition electronic reconnaissance deinterleaving selfdistilled Pulse Sequence Pattern(PSP)
安徽工业大学 电气信息学院, 安徽 马鞍山243002
由于多普勒信号处理技术在整个激光多普勒测速(LDV)系统中起到关键作用, 针对仅利用快速傅里叶变换处理多普勒信号存在精度低的问题, 频谱校正方法的研究显得十分必要。通过阐述比值法、能量重心法和相位差法三种离散频谱校正方法的基本原理和仿真实验, 表明三种方法均可使校正频率更加接近真实值。考虑到算法的复杂度和抗噪性能等因素的影响, 选用了能量重心法对实测多普勒信号进行频率校正, 且校正效果明显。
信号处理 激光多普勒测速仪 离散频谱校正 快速傅里叶变换 signal processing laser Dopplor velocimeter discrete spectrum correction fast Fourier transform
