1 中国民航大学 天津市空管运行规划与安全技术重点实验室 天津 300300
2 天津大学 光电信息技术教育部重点实验室 天津 300072
3 中国民航大学 天津市智能信号与图像处理重点实验室 天津 300300
针对单基线能见度测量设备采样体积单一、受噪声影响大的缺点, 设计搭建了一套移动式可变基线能见度测试系统.该系统由发射、接收、移动以及信号处理四个模块组成, 以532 nm激光作为发射光源, 通过置于滑动轨道上的小车移动定点接收发射信号实现多基线测量, 然后采用时间平均结合最小二乘法对初始信号进行处理获得最终大气能见度.系统采用单端移动接收采样法, 可从理论上消除光学污染误差.理论分析了该设备的测量方差及基线采样点模型, 并对系统进行加噪声模拟实验, 证明了其抗噪声能力; 最后在真实大气环境下对设备进行检验, 通过与实际数据对比证明其可靠性.
能见度 探测 最小二乘法 可变基线 抗噪声 Visibility Detection Least squares method Variable baselines Anti-noise
Author Affiliations
Abstract
1 College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
2 Civil Aviation Meteorological Institute, Key Laboratory of Operation Programming and Safety Technology of Air Traffic Management, Civil Aviation University of China, Tianjin 300300, China
The carrier envelope phase (CEP) has a direct impact on the physical properties of an isolated attosecond pulse (IAP) and many strong field processes, but it is difficult to measure in reality. Aiming at obtaining more accurate and complete characterization of CEP, we numerically investigate the annular photoelectron momentum spectra of the hydrogen atom ionized by overlapped fields of an IAP and an infrared (IR) pulse. By defining an overlapping parameter, the momentum patterns are classified and optimized for unambiguously measuring the rotation angle of a momentum pattern versus the CEP value. A series of simulations verify its robustness.
020.2649 Strong field laser physics Chinese Optics Letters
2017, 15(11): 110201
Author Affiliations
Abstract
1 College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
2 Civil Aviation Meteorological Institute, Key Laboratory of Operation Programming & Safety Technology of Air Traffic Management, Civil Aviation University of China, Tianjin 300300, China
The photoionization by two elliptically polarized, time delayed attosecond pulses is investigated to display a momentum distribution having the helical vortex or ring structures. The results are obtained by the strong field approximation method and analyzed by the pulse decomposition. The ellipticities and time delay of the two attosecond pulses are found to determine the rotational symmetry and the number of vortex arms. For observing these vortex patterns, the energy bandwidth and temporal duration of the attosecond pulses are ideal.
020.2649 Strong field laser physics 020.0020 Atomic and molecular physics Chinese Optics Letters
2017, 15(12): 120202
