Laser Coherent Detection Research Articles

Receiving characteristics analysis of large dynamic range based on four-optic coherent mixing

Aiming at the problem that the maximum measurement speed of conventional laser coherent detection is limited, a four-optical coherent mixing large dynamic range Doppler measurement method is proposed. The speed measurement range of this method is nearly doubled, and the speed measurement of high-speed and ultra-high-speed targets can be achieved. The SNR is a key reference quantity for the four-light coherent mixing performance. Therefore, a theoretical analysis was carried out from the spatial coherence length, receiving aperture, and mismatch angle. Through theoretical and simulation analysis, the optimal relationship between the aperture coherence length and the receiving aperture is obtained.

Light intensity and spatial coherence characteristics of laser coherent detection in a turbulent atmosphere

The predecessor of China Optics was China Optics and Applied Optics Digest, which was founded in 1985. At that time, it was the only retrieval journal in the field of optics in China. At the end of 2008, China Optics and Applied Optics Digest was renamed

强度扰动对双频激光相干探测性能的影响

强度扰动对双频激光相干探测性能的影响

Expanding research on laser coherent detection of underwater sound source

For the purpose of getting underwater acoustic source information, a new method is proposed to detect underwater acoustic source by means of laser interference based on the principle of Michelson interferometer. Information such as frequency and amplitude of underwater acoustic field can be concluded from the interference of reflected laser beams from the water surface with a reference beam. Laser coherent detection acquires information from the water surface in real time under the condition that the source is located underwater 37cm, with 3000Hz vibration. In terms of information processing and analysis, the original signal is filtered and processed by wavelet transform and Wigner-Ville distribution in this paper in addition to using the traditional Fourier analysis method, in order to achieve the purpose of the extraction and enhancement of weak feature signals.

时频扰动对双频激光相干探测系统的影响

时频扰动对双频激光相干探测系统的影响

Detection on micro-Doppler effect based on 1550 nm laser coherent radar

A laser coherent detection system of 1550nm wavelength was presented, and experimental research on detecting micro-Doppler effect in a dynamic target was developed. In this paper, the return signal in the time domain is decomposed into a set of components in different wavelet-scales by multi-resolution analysis, and the components are associated with the vibrational motions in a target. The micro-Doppler signatures are extracted by applying the reconstruction (inverse wavelet transform). During the course of the final data processing frequency analysis and time–frequency analysis are applied to analyze the vibrational signals and estimate the motion parameters successfully. The experimental results indicate that the micro-Doppler information in a moving can be effectively detected, and tiny vibrational signatures also can be acquired effectively by wavelet multi-resolution analysis and time–frequency analysis.

Detection on micro-Doppler effect based on laser coherent radar

A laser coherent detection system of 1550 nm wavelength was presented, and experimental research on detecting micro-Doppler effect in a dynamic target was developed. In the study, the return signal in the time domain is decomposed into a set of components in different wavelet scales by multi-resolution wavelet analysis, and the components are associated with the vibrational motions in a target. Then micro-Doppler signatures are extracted by applying the reconstruction. During the course of the final data processing frequency analysis and time-frequency analysis are applied to analyze the vibrational signals and estimate the motion parameters successfully. The experimental results indicate that the system can effectively detect micro-Doppler information in a moving target, and the tiny vibrational signatures also can be acquired effectively by wavelet multi-resolution analysis and time-frequency analysis.

运动目标微多普勒效应的激光雷达相干探测及特征提取

运动目标微多普勒效应的激光雷达相干探测及特征提取